- Aug 2024
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www.washingtonpost.com www.washingtonpost.com
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The South Florida influencers, for instance, heard a rumor circulating that the government had put microchips in the coronavirus vaccine so it could track people.
Notice that many fake news stories begin from a place of fear. This fear hijacks our brains and triggers fight or flight options in our system I circuitry and actively prevent the use of the rational parts of system II which would quickly reveal problems in the information.
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- Jun 2024
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our failure today will be irreversible soon in the next 12 to 24 months we will leak key AGI breakthroughs to the CCP it will 00:38:56 be to the National security establishment the greatest regret before the decade is out
for - AI - security risk - next 1 to 2 years is vulnerable time to keep AI secrets out of hands of authoritarian regimes
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- Apr 2024
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docdrop.org docdrop.org
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regularity
for - sleep hygiene - 1 - regularity
advice - sleep hygiene - 1 - regularity - try to make weekend sleep times same as weekday - don't deviate if possible
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- Mar 2024
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www.legifrance.gouv.fr www.legifrance.gouv.fr
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L'enseignant référent qui coordonne les équipes de suivi de la scolarisation est l'interlocuteur des familles pour la mise en place du projet personnalisé de scolarisation.
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www.snpden.net www.snpden.net
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"Il résulte donc de ce qui précède, qu’en l’absence d’obstacle juridique, l’organe délibératif de l’EPLE est parfaitement libre d’adopter le principe d’une répartition de l’année scolaire en deux semestres, au lieu de trois trimestres. Une fois cette résolution arrêtée, il conviendra également de modifier en conséquence le règlement intérieur de l’établissement."
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www.liberatingstructures.com www.liberatingstructures.com
- Feb 2024
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www.youtube.com www.youtube.com
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A useful model for note-taking is that of system 1 and 2 thinking. Try to do as much as possible in system 1. So, most work is done without much work and effort. Chris places his hypothesis.is workflow within system 1.
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www.derstandard.de www.derstandard.de
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Langes Interview mit Hans Joachim Schellnhuber im Standard, under anderem zu Kipppunkten und der Möglichkeit, dass wir uns schon auf dem Weg in ein „neues Klimaregime“ befinden. Schellnhuber geht davon aus, dass auch das 2°-Ziel überschritten werden wird. Der „Königsweg“, um der Atmosphäre danach wieder CO<sub>2</sub> zu entziehen, sei der weltweite Ersatz von Zement durch Holz beim Bauen, den er als Direktor des IIASA vor allem erforschen wolle. Die Wahrscheinlichkeit dafür, dass „noch alles gutgehen" werde, sei gering. https://www.derstandard.at/story/3000000204635/klimaforscher-schellnhuber-werden-auch-ueber-das-zwei-grad-ziel-hinausschiessen
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- Jan 2024
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mongoosejs.com mongoosejs.com
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Instance methods Instances of Models are documents. Documents have many of their own built-in instance methods. We may also define our own custom document instance methods. // define a schema const animalSchema = new Schema({ name: String, type: String }, { // Assign a function to the "methods" object of our animalSchema through schema options. // By following this approach, there is no need to create a separate TS type to define the type of the instance functions. methods: { findSimilarTypes(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); } } }); // Or, assign a function to the "methods" object of our animalSchema animalSchema.methods.findSimilarTypes = function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); }; Now all of our animal instances have a findSimilarTypes method available to them. const Animal = mongoose.model('Animal', animalSchema); const dog = new Animal({ type: 'dog' }); dog.findSimilarTypes((err, dogs) => { console.log(dogs); // woof }); Overwriting a default mongoose document method may lead to unpredictable results. See this for more details. The example above uses the Schema.methods object directly to save an instance method. You can also use the Schema.method() helper as described here. Do not declare methods using ES6 arrow functions (=>). Arrow functions explicitly prevent binding this, so your method will not have access to the document and the above examples will not work.
Certainly! Let's break down the provided code snippets:
1. What is it and why is it used?
In Mongoose, a schema is a blueprint for defining the structure of documents within a collection. When you define a schema, you can also attach methods to it. These methods become instance methods, meaning they are available on the individual documents (instances) created from that schema.
Instance methods are useful for encapsulating functionality related to a specific document or model instance. They allow you to define custom behavior that can be executed on a specific document. In the given example, the
findSimilarTypes
method is added to instances of theAnimal
model, making it easy to find other animals of the same type.2. Syntax:
Using
methods
object directly in the schema options:javascript const animalSchema = new Schema( { name: String, type: String }, { methods: { findSimilarTypes(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); } } } );
Using
methods
object directly in the schema:javascript animalSchema.methods.findSimilarTypes = function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); };
Using
Schema.method()
helper:javascript animalSchema.method('findSimilarTypes', function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); });
3. Explanation in Simple Words with Examples:
Why it's Used:
Imagine you have a collection of animals in your database, and you want to find other animals of the same type. Instead of writing the same logic repeatedly, you can define a method that can be called on each animal instance to find similar types. This helps in keeping your code DRY (Don't Repeat Yourself) and makes it easier to maintain.
Example:
```javascript const mongoose = require('mongoose'); const { Schema } = mongoose;
// Define a schema with a custom instance method const animalSchema = new Schema({ name: String, type: String });
// Add a custom instance method to find similar types animalSchema.methods.findSimilarTypes = function(cb) { return mongoose.model('Animal').find({ type: this.type }, cb); };
// Create the Animal model using the schema const Animal = mongoose.model('Animal', animalSchema);
// Create an instance of Animal const dog = new Animal({ type: 'dog', name: 'Buddy' });
// Use the custom method to find similar types dog.findSimilarTypes((err, similarAnimals) => { console.log(similarAnimals); }); ```
In this example,
findSimilarTypes
is a custom instance method added to theAnimal
schema. When you create an instance of theAnimal
model (e.g., a dog), you can then callfindSimilarTypes
on that instance to find other animals with the same type. The method uses thethis.type
property, which refers to the type of the current animal instance. This allows you to easily reuse the logic for finding similar types across different instances of theAnimal
model.
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www.a5-size.com www.a5-size.com
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The first time the ratio of length to width was written in a letter dated 25 October 1786. This letter was from the German Georg Christoph Lichtenberg to Johann Beckmann. He wrote here about the advantages of basing paper on a √2 ratio. Lichtenberg is known for the ratio between length and width of a surface which remains the same after the narrated halving of the surface. The result is 1:√2.
Sourcing? Look this up.<br /> https://www.a5-size.com/history/
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- Nov 2023
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www.edge.org www.edge.orgEdge.org1
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Ashby's law of requisite variety may also be at play for overloading our system 1 heuristic abilities with respect to misinformation (particularly in high velocity social media settings). Switching context from system 1 to system 2 on a constant basis to fact check everything in our (new digital) immediate environment can be very mentally and emotionally taxing. This can result in both mental exhaustion as well as anxiety.
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forum.zettelkasten.de forum.zettelkasten.de
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Your comment inspires me to pay more attention to citing and clarifying my claims.
replying to Will at https://forum.zettelkasten.de/discussion/comment/18885/#Comment_18885
I've generally found that this is much easier to do when it's an area you tend to specialize in and want to delve ever deeper (or on which you have larger areas within your zettelkasten) versus those subjects which you care less about or don't tend to have as much patience for.
Perhaps it's related to the System 1/System 2 thinking of Kahneman/Tversky? There are only some things that seem worth System 2 thinking/clarifying/citing and for all the rest one relies on System 1 heuristics. I find that the general ease of use of my zettelkasten (with lots of practice) allows me to do a lot more System 2 thinking than I had previously done, even for areas which I don't care as much about.
syndication link: https://forum.zettelkasten.de/discussion/comment/18888/#Comment_18888
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- Oct 2023
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en.wikipedia.org en.wikipedia.org
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https://en.wikipedia.org/wiki/Shmita
During shmita, the land is left to lie fallow and all agricultural activity, including plowing, planting, pruning and harvesting, is forbidden by halakha (Jewish law).
The sabbath year (shmita; Hebrew: שמיטה, literally "release"), also called the sabbatical year or shǝvi'it (שביעית, literally "seventh"), or "Sabbath of The Land", is the seventh year of the seven-year agricultural cycle mandated by the Torah in the Land of Israel and is observed in Judaism.
Tags
- Jeremiah 34:13-14
- agriculture
- 2 Chronicles 36:20-21
- jubilee
- remission year
- halakha
- Deuteronomy 15:1-6
- Nehemiah 10:31
- sabbaticals
- Isaiah 37:30
- time in relation to work
- debt
- Exodus 23:10-11
- 2 Kings 19:29
- shmita
- Leviticus 25
- Deuteronomy 31:10-13
- Jewish law
- Leviticus 25:5
- Friends of the Link 2023-10-18
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claudemariottini.com claudemariottini.com
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There are several occasions where the massebah is not associated with pagan worship. When the massebah is associated with the worship of Yahweh, the massebah is accepted as a valid expression of commitment to Yahweh.
Massebah for pagan worship: - Exodus 23:24 (https://hypothes.is/a/r3m5QmyDEe6SC8eLYcJE1Q) - Hosea 10:1 (https://hypothes.is/a/4PK2GGyDEe6wZg_r2YpVCA ) - 2 Kings 18:4 - 2 Kings 23:14
Massebah for worship of Yahweh: - Genesis 28:18 Jacob's pillow (https://hypothes.is/a/NF5p8Gx6Ee65Rg_J4tfaMQ)<br /> - Genesis 31:44-45 Jacob and Laban's covenant - Exodus 24:4 - Joshua 24:25-27
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in violation of the demands of the covenant, the people of Israel erected sacred stones dedicated to other gods (Hosea 10:1). In their religious reforms, both Hezekiah (2 Kings 18:4) and Josiah (2 Kings 23:14) destroyed the sacred pillars which the people of Israel had dedicated to the worship of Baal.
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During the establishment of the covenant between Yahweh and Israel, the people were commanded to destroy the sacred stones of the Canaanites, “You must demolish them and break their sacred stones (masseboth) to pieces” (Exodus 23:24).
In neighboring cultures in which both have oral practices relating to massebah, one is not just destroying "sacred stones" to stamp out their religion, but it's also destroying their culture and cultural memory as well as likely their laws and other valuable memories for the function of their society.
View this in light also of the people of Israel keeping their own sacred stones (Hosea 10:1) as well as the destruction of pillars dedicated to Baal in 2 Kings 18:4 and 2 Kings 23:14.
(Link and) Compare this to the British fencing off the land in Australia and thereby destroying Songlines and access to them and the impact this had on Indigenous Australians.
It's also somewhat similar to the colonialization activity of stamping out of Indigenous Americans and First Nations' language in North America, though the decimation of their language wasn't viewed in as reciprocal way as it might be viewed now. (Did colonizers of the time know about the tremendous damage of language destruction, or was it just a power over function?)
Tags
- The Covenant
- masseboth
- colonization
- songlines
- Hosea 10:1
- Exodus 23
- Canaanite religion
- Joshua 24:25-27
- Indigenous languages
- standing stones
- Genesis 28:18
- hypocrisy
- what's good for the goose is good for the gander
- Exodus 23:24
- biblical stones
- 2 Kings 23:14
- Exodus 24:4
- Genesis 31:44-45
- orality and memory
- 2 Kings 18:4
- Hezekiah
- Josiah
- Baal
- massebah
- sacred stones
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URL
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- Jul 2023
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- Title
- Big Oil v the World Series 1 02 Doubt
- Author BBC
- Title
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- Apr 2023
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datatracker.ietf.org datatracker.ietf.org
- Mar 2023
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books.googleusercontent.com books.googleusercontent.comcontent1
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2 3-4 x 4 3-4 inches in size, made of seal grain , real sealor Russia leather, in a thoro
Memindex dimensions mentioned in a 1904 advertisement<br /> cards: 2 3/4 x 4 1/2 inches<br /> case: 2 3/4 x 4 3/4 inches
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www.ebay.com www.ebay.com
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1930s Wilson Memindex Co Index Card Organizer Pre Rolodex Ad Price List Brochure
archived page: https://web.archive.org/web/20230310010450/https://www.ebay.com/itm/165910049390
Includes price lists
List of cards includes: - Dated tab cards for a year from any desired. - Blank tab cards for jottings arranged by subject. - These were sold in 1/2 or 1/3 cut formats - Pocket Alphabets for jottings arranged by letter. - Cash Account Cards [without tabs]. - Extra Record Cards for permanent memoranda. - Monthly Guides for quick reference to future dates. - Blank Guides for filing records by subject.. - Alphabet Guides for filing alphabetically.
Memindex sales brochures recommended the 3 x 5" cards (which had apparently been standardized by 1930 compared to the 5 1/2" width from earlier versions around 1906) because they could be used with other 3 x 5" index card systems.
In the 1930s Wilson Memindex Company sold more of their vest pocket sized 2 1/4 x 4 1/2" systems than 3 x 5" systems.
Some of the difference between the vest sized and regular sized systems choice was based on the size of the particular user's handwriting. It was recommended that those with larger handwriting use the larger cards.
By the 1930's at least the Memindex tag line "An Automatic Memory" was being used, which also gave an indication of the ubiquity of automatization of industrialized life.
The Memindex has proved its success in more than one hundred kinds of business. Highly recommended by men in executive positions, merchants, manufacturers, managers, .... etc.
Notice the gendering of users specifically as men here.
Features: - Sunday cards were sold separately and by my reading were full length tabs rather than 1/6 tabs like the other six days of the week - Lids were custom fit to the bases and needed to be ordered together - The Memindex Jr. held 400 cards versus the larger 9 inch standard trays which had space for 800 cards and block (presumably a block to hold them up or at an angle when partially empty).
The Memindex Jr., according to a price sheet in the 1930s, was used "extensively as an advertising gift".
The Memindex system had cards available in bundles of 100 that were labeled with the heading "Things to Keep in Sight".
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312 Oak Midget Tray WWeesCoverEquipped same as]No.324,price.55CTohold cards14x3.No.423.Equippedasabove,tohold65Ccards 24x4, priceNo. 533. Standard size.to hold card 3x5, equip-ped as above,price..........No. 7- Nickel ....PrepaidinU. S.onreceiptofpriceNo. 324OakMidgetTraytheCoverWeis75cNo. 644. To hold cards4x6,equipped$1.10(StyleNos.312,423.533and644)asabove......(Style No. 324,213.335and446.)Send for catalog showing many other time-saving office devices. Our goods are soldyour dealer does not carry our line we can supply you direct from the factory.To hold cards 24x4. lengthof tray2%in..equippedwithAtoZindexand100record cards 45cNo. 213. To hold cards 14x3in,, lenght of tray 24in..equipped asabove40cNo.335.Standardsize,tohold3x5 cards.equipped asabove50c80cNo. 446. To hold 4x6 cards,equipped asabove.Any of these trays sent pre-paid in U. S. on receipt ofpriceby stationers everywhere. IfNo. 6 Union St.The WeisManufacturing Co.,Monroe,Mich.,U. S.A.Please mention SYSTEM when writing to advertisers
Notice the 1 1/4" x 3" cards, 2 1/4 x 4" cards in addition to the 3 x 5" and 4 x 6".
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- Feb 2023
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sakai.claremont.edu sakai.claremont.edu
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Cultural geography = human science, approach to the lives of people. Investigates relevance of culture to the global society today. * Contrast between mental and natural space * Space can be produced by society, but society creates itself within a cultural space
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- Jan 2023
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Weread, for example, of Philistine incursions into the hill country, toMichmash in Benjamin (1 Samuel 13:23), and the Rephaim Valley nearJerusalem (2 Samuel 5:17–22). It was in one of these border disputes thatthe city at Khirbet Qeiyafa was conquered and destroyed.
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docdrop.org docdrop.org
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hume is not in book one arguing that persons do not exist in fact in book two he's going to spend most of his time explaining what persons 01:17:41 are he when instead what he's claiming is that persons don't have selves
!- David Hume : book 1 and 2 - book 1 explains what persons are - book 2 explains that persons don't have selves
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- Dec 2022
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Local file Local file
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remind us of the historical reduction of the human to the status of ananimal under transatlantic slavery, but also were used as a mode of resistancefor enslaved peoples
first half is type 1, first half is type 2
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- Jul 2022
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gist.github.com gist.github.com
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5.1 Recognize that 1) the biggest threat to good decision making is harmful emotions, and 2) decision making is a two-step process (first learning and then deciding).
5.1 Recognize that 1) the biggest threat to good decision making is harmful emotions, and 2) decision making is a two-step process (first learning and then deciding).
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so let's suppose let's suppose your listeners are with me and you know we kind of agree like okay yes transformation's necessary and uh again i want to emphasize i'm not talking about reform i'm not talking 00:58:59 about a softer better capitalism i'm not talking about you know improved voter registration or like any of those things i'm talking about de novo starting over from scratch what might be 00:59:13 best and if it turns out that the old systems were better than anything that humanity can come up with well then you know that's the answer but i can't imagine that's true because the old systems were never designed in any kind of 00:59:25 you know thoughtful science driven [Music] you know process to to to test to explore and to come up with fitness like what is the you know we don't even have a fitness for our current society 00:59:39 much less of fitness for societal designs i mean we have the gdp but that's a terrible terrible limited fitness metric 00:59:51 okay so suppose you're with me suppose we're we're on board we we want to do this de novo design thing where do we start what's the what's what where do we even get off the 01:00:03 ground on this and i suggest that the way to do it is through first address worldview from world view once we understand what the world view is 01:00:15 what a reasonable useful world view will be for this project then then purpose derives worldview begets purpose once you understand what it is you want 01:00:28 what you value what do you value once you understand what you value then you can say well i value a and therefore the purpose is to 01:00:39 have a manifest in society for example so once you have purpose then you can think about what metrics how would you measure whether are you so 01:00:53 here's a new design is it fit for purpose does it do does it fulfill its purpose you know that's the question and then metrics go with some kind of fitness evaluation 01:01:05 and then finally last of all of those would be the design okay we know what we know what we value we know what this thing is supposed to do we know what the purpose is we know that attractor is supposed to you know plow the ground or something we 01:01:18 know what this is supposed to do we know how to measure success and uh now finally then let's talk about design what are the what are the you know the specifics and mechanics and 01:01:31 how does that happen and the the series is really kind of laid out this way the first paper really talks about world view and purpose the second paper talks about the you know the more the mechanics of things 01:01:44 like viability how would you make this thing viable things like that and then the very last paper that's titled the subtitle design okay so uh that's how we uh and 01:01:56 and maybe i will just mention here that i put metrics before design because we might have some ideas uh getting back to that preference factor we might have some ideas like we would like people not to die at 01:02:08 30 you know we'd like people to mostly live to a ripe old age and have you know enough water water to drink and food to eat and all that kind of stuff so uh you know what kind of design once 01:02:20 now that we have metrics to measure that kind of stuff longevity and nutrition and things what kind of designs would help us to reach those targets you know so that's one reason why design 01:02:31 why metrics comes before design okay
Process flow: Worldview, purpose, metric and finally design
Paper 1: Worldview and purpose Paper 2: practical implementation Paper 3: Design
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URL
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- May 2022
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www.thecut.com www.thecut.com
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Matt Taibbi asked his subscribers in April. Since they were “now functionally my editor,” he was seeking their advice on potential reporting projects. One suggestion — that he write about Ibram X. Kendi and Robin DiAngelo — swiftly gave way to a long debate among readers over whether race was biological.
There's something here that's akin to the idea of bikeshedding? Online communities flock to the low lying ideas upon which they can proffer an opinion and play at the idea of debate. If they really cared, wouldn't they instead delve into the research and topics themselves? Do they really want Taibbi's specific take? Do they want or need his opinion on the topic? What do they really want?
Compare and cross reference this with the ideas presented by Ibram X. Kendi's article There Is No Debate Over Critical Race Theory.
Are people looking for the social equivalent of a simple "system one" conversation or are they ready, willing, and able to delve into a "system two" presentation?
Compare this also with the modern day version of the Sunday morning news (analysis) shows? They would seem to be interested in substantive policy and debate, but they also require a lot of prior context to participate. In essence, most speakers don't actually engage, but spew out talking points instead and rely on gut reactions and fear, uncertainty and doubt to make their presentations. What happened to the actual discourse? Has there been a shift in how these shows work and present since the rise of the Hard Copy sensationalist presentation? Is the competition for eyeballs weakening these analysis shows?
How might this all relate to low level mansplaining as well? What are men really trying to communicate in demonstrating this behavior? What do they gain in the long run? What is the evolutionary benefit?
All these topics seem related somehow within the spectrum of communication and what people look for and choose in what and how they consume content.
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- Apr 2022
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twitter.com twitter.com
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ReconfigBehSci. (2022, January 31). RT @fascinatorfun: Interesting as 🇩🇰 Omicron BA2 wave started sooner than 🇬🇧 “We conclude that Omicron BA.2 is inherently substantially m… [Tweet]. @SciBeh. https://twitter.com/SciBeh/status/1488152457012297736
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twitter.com twitter.com
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John Roberts. (2022, January 28). Some (very) early evidence that secondary attack rates of BA.2 are higher in household settings than those of its older sibling. From the latest Variant TB 35. Https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1050999/Technical-Briefing-35-28January2022.pdf 1/ https://t.co/AFTril1jF1 [Tweet]. @john_actuary. https://twitter.com/john_actuary/status/1487086733149749251
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twitter.com twitter.com
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ReconfigBehSci. (2022, January 23). RT @LauraMiers: BA.2’s growth advantage over BA.1 is jarring. Meanwhile, we are operating under the assumption that “Omicron will end the p… [Tweet]. @SciBeh. https://twitter.com/SciBeh/status/1485519516914302980
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- Mar 2022
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learn-us-east-1-prod-fleet02-xythos.content.blackboardcdn.com learn-us-east-1-prod-fleet02-xythos.content.blackboardcdn.comLayout 11
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the combination of trading patterns and pref-erences of European planters in the Americas for laborers of specific Africanethnicities tended to lump together large numbers of captive Africans from cer-tain areas into particular colonies in the Americas.
how the enslaved kept their honor, history, martial arts
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www.forbes.com www.forbes.com
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Haseltine, W. A. (n.d.). Birth Of The Omicron Family: BA.1, BA.2, BA.3. Each As Different As Alpha Is From Delta. Forbes. Retrieved 30 March 2022, from https://www.forbes.com/sites/williamhaseltine/2022/01/26/birth-of-the-omicron-family-ba1-ba2-ba3-each-as-different-as-alpha-is-from-delta/
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twitter.com twitter.com
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ReconfigBehSci. (2022, March 11). RT @dgurdasani1: UKHSA tech report out—TL;DR: -BA.2 now represents >80% of omicron in England -Growth rate 80% greater relative to BA.1 p… [Tweet]. @SciBeh. https://twitter.com/SciBeh/status/1502598815081275393
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- Sep 2021
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L’esercizio fisico deve essere raccomandato per il controllo del diabete nelle persone con diabete di tipo 2?
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
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www.commbank.com.au www.commbank.com.au
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help you save
Unsubstantiated claims
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- Aug 2021
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awarm.space awarm.space
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I like the differentiation that Jared has made here on his homepage with categories for "fast" and "slow".
It's reminiscent of the system 1 (fast) and system2 (slow) ideas behind Kahneman and Tversky's work in behavioral economics. (See Thinking, Fast and Slow)
It's also interesting in light of this tweet which came up recently:
<script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>I very much miss the back and forth with blog posts responding to blog posts, a slow moving argument where we had time to think.
— Rachel Andrew (@rachelandrew) August 22, 2017Because the Tweet was shared out of context several years later, someone (accidentally?) replied to it as if it were contemporaneous. When called out for not watching the date of the post, their reply was "you do slow web your way…" #
This gets one thinking. Perhaps it would help more people's contextual thinking if more sites specifically labeled their posts as fast and slow (or gave a 1-10 rating?). Sometimes the length of a response is an indicator of the thought put into it, thought not always as there's also the oft-quoted aphorism: "If I Had More Time, I Would Have Written a Shorter Letter".
The ease of use of the UI on Twitter seems to broadly make it a platform for "fast" posting which can often cause ruffled feathers, sour feelings, anger, and poor communication.
What if there were posting UIs (or micropub clients) that would hold onto your responses for a few hours, days, or even a week and then remind you about them after that time had past to see if they were still worth posting? This is a feature based on Abraham Lincoln's idea of a "hot letter" or angry letter, which he advised people to write often, but never send.
Where is the social media service for hot posts that save all your vituperation, but don't show them to anyone? Or which maybe posts them anonymously?
The opposite of some of this are the partially baked or even fully thought out posts that one hears about anecdotally, but which the authors say they felt weren't finish and thus didn't publish them. Wouldn't it be better to hit publish on these than those nasty quick replies? How can we create UI for this?
I saw a sitcom a few years ago where a girl admonished her friend (an oblivious boy) for liking really old Instagram posts of a girl he was interested in. She said that deep-liking old photos was an obvious and overt sign of flirting.
If this is the case then there's obviously a social standard of sorts for this, so why not hold your tongue in the meanwhile, and come up with something more thought out to send your digital love to someone instead of providing a (knee-)jerk reaction?
Of course now I can't help but think of the annotations I've been making in my copy of Lucretius' On the Nature of Things. Do you suppose that Lucretius knows I'm in love?
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- Jul 2021
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halfanhour.blogspot.com halfanhour.blogspot.com
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Well, no. I oppose capital punishment, just as (in my view) any ethical person should oppose capital punishment. Not because innocent people might be executed (though that is an entirely foreseeable consequence) but because, if we allow for capital punishment, then what makes murder wrong isn't the fact that you killed someone, it's that you killed someone without the proper paperwork. And I refuse to accept that it's morally acceptable to kill someone just because you've been given permission to do so.
Most murders are system 1-based and spur-of-the-moment.
System 2-based murders are even more deplorable because in most ethical systems it means the person actively spent time and planning to carry the murder out. The second category includes pre-meditated murder, murder-for-hire as well as all forms of capital punishment.
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- May 2021
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interpersonal.stackexchange.com interpersonal.stackexchange.com
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One solution that fixed this issue with my ISP was that when I went through the first and second line and got in touch with the people that fixed my problem, I asked them if they could give me one of their personal numbers in case the same problem happened again. The problem did occur a couple more times, and I just directly called the same guy.
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www.nature.com www.nature.com
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Kreier, F. (2021). ‘Unprecedented achievement’: Who received the first billion COVID vaccinations? Nature. https://doi.org/10.1038/d41586-021-01136-2
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www.washingtonpost.com www.washingtonpost.com
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Blakemore, E. (n.d.). New diabetes cases linked to covid-19. Washington Post. Retrieved February 11, 2021, from https://www.washingtonpost.com/health/2021/02/01/covid-new-onset-diabetes/
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- Mar 2021
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www.ncbi.nlm.nih.gov www.ncbi.nlm.nih.gov
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Results for individual PALB2 variants were normalized relative to WT-PALB2 and the p.Tyr551ter (p.Y551X) truncating variant on a 1:5 scale with the fold change in GFP-positive cells for WT set at 5.0 and fold change GFP-positive cells for p.Y551X set at 1.0. The p.L24S (c.71T>C), p.L35P (c.104T>C), p.I944N (c.2831T>A), and p.L1070P (c.3209T>C) variants and all protein-truncating frame-shift and deletion variants tested were deficient in HDR activity, with normalized fold change <2.0 (approximately 40% activity) (Fig. 1a).
AssayResult: 5.3
AssayResultAssertion: Normal
StandardErrorMean: 0.46
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www.ncbi.nlm.nih.gov www.ncbi.nlm.nih.gov
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SUPPLEMENTARY DATA
AssayResult: -98
AssayResultAssertion: Abnormal
PValue: < 0.0001
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SUPPLEMENTARY DATA
AssayResult: 85.76
AssayResultAssertion: Indeterminate
PValue: 0.0445
Comment: Exact values reported in Table S3.
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www.ncbi.nlm.nih.gov www.ncbi.nlm.nih.gov
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Source Data
AssayResult: 115.71
AssayResultAssertion: Not reported
ReplicateCount: 2
StandardErrorMean: 3.09
Comment: Exact values reported in “Source Data” file.
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Source Data
AssayResult: 11.28
AssayResultAssertion: Abnormal
ReplicateCount: 2
StandardDeviation: 1.24
StandardErrorMean: 0.87
Comment: Exact values reported in “Source Data” file.
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www.cell.com www.cell.com
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Most Suspected Brugada Syndrome Variants Had (Partial) Loss of Function
AssayResult: 113.2
AssayResultAssertion: Normal
ReplicateCount: 30
StandardErrorMean: 13.9
Comment: This variant had normal function (75-125% of wildtype peak current, <1% late current, no large perturbations to other parameters). These in vitro features are consistent with non-disease causing variants. (Personal communication: A. Glazer)
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- Feb 2021
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jmg.bmj.com jmg.bmj.com
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Supplemental material
AssayResult: 7.1
AssayResultAssertion: Abnormal
Comment: See Table S2 for details
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- Jan 2021
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www.biorxiv.org www.biorxiv.org
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Reviewer #2:
In this paper, Numssen and co-workers focus on the functional differences between hemispheres to investigate the "domain-role" of IPL in different types of mental processes. They employ multivariate pattern-learning algorithms to assess the specific involvement of two IPL subregions in three tasks: an attentional task (Attention), a semantic task (Semantics) and a social task (Social cognition). The authors describe how, when involved in different tasks, each right and left IPL subregion recruits a different pattern of connected areas.
The employed tasks are "well established", and the results confirm previous findings. However, the novelty of the paper lies in the fact that the authors use these results as a tool to observe IPL activity when involved in different domains of cognition.
The methodology is sound, well explained in the method section, the analyses are appropriate, and the results clear and well explained in the text and in graphic format.
However, a solid experimental design is required to provide strong results. To the reviewer's view, the employed design can provide interesting results about functional connectivity, but not about the functional role of IPL in the investigated functions.
I think the study would be correct and much more interesting if only based on functional connectivity data. Note that rewriting the paper accordingly would lead to a thorough discussion about how anatomical circuits are differently recruited based on different cognitive demands and about the variable role of cortical regions in functional tasks. This issue is neglected in the present discussion, and this concept is in disagreement with the main results, suggesting (probably beyond the intention of the authors) that different parts of the right and left IPL are the areas responsible for the studied functions.
Major points:
1) The 3 chosen tasks explore functions that are widespread in the brain, and are not specifically aimed at investigating IPL. The results (see. e.g. fig 1) confirm this idea, but the authors specifically focus on IPL. This seems a rather arbitrary and not justified choice. If they want to explore the lateralization issue, they should consider the whole set of involved areas or use tasks showing all their maximal activation in IPL.
2) The authors aims to study lateralization using an attentional task, considering the violation of a prevision (invalid>valid), a linguistic task, looking for an activation related to word identification (word>pseudoword) and a social task, considering correct perspective taking (false belief>true belief), but they do not consider that in all cases a movement (key press) is required. It is well known that IPL is a key area also for creating motor commands and guiding movements. Accordingly, the lateralization bias observed could be due more to the unbalance between effectors while issuing the motor command, than to a different involvement of IPL regions in the specific tasks functions.
3) Like point 2, the position of keys is also crucial if the authors want to explore lateralization. This is especially important if one considers that IPL plays a major role in spatial attention (e.g. Neglect syndrome). In the Methods, the authors simply say "Button assignments were randomized across subjects and kept identical across sessions", this should be explained in more detail.
4) The authors show to know well the anatomical complexity of IPL, however their results are referred to two large-multiareal-regions. This seems to the reader at odds with all the descriptions related to fig.2. If they don't find any more subtle distinction within these 2 macro-regions, they should at least discuss this discrepancy.
5) The part about Task-specific network connectivity is indeed very interesting, I would suggest to the authors to focus exclusively on this part. (Note that the results of this part seems to confirm that only the linguistic task is able to show a clear lateralization).
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- Oct 2020
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So unfortunately 1 step forward, 2 steps back.
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- Jun 2020
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www.ft.com www.ft.com
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Ahuja, A. (2020, June 16). The two-metre rule and other imperfect Covid-19 risk calculations | Free to read. https://www.ft.com/content/30adbfa1-178f-47e2-97a8-bd41ca590999
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- Apr 2020
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d18ky98rnyall9.cloudfront.net d18ky98rnyall9.cloudfront.net
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Chapter 3Biopsychology
This is the scope of Test 2.
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- Sep 2019
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lincyi.pixnet.net lincyi.pixnet.net
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道地
分類:2-1
- M: yes
Tags
Annotators
URL
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flower033880.pixnet.net flower033880.pixnet.net
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真材實料
分類:2-1
- M: yes
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vhygdih0412.pixnet.net vhygdih0412.pixnet.net
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平價
分類:2-1
- M: yes
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styleme.pixnet.net styleme.pixnet.net
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清爽
分類:2-1
- M: yes
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滿嘴
分類:2-1
- M: yes
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推出
分類:2
- M: yes
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鳳梨酥
分類:2
- M: yes
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Sampling point, Sample Size and Sample collection
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- Jul 2019
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Sequence analysis
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DNA sequencing of the 18S rDNA fragment
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Purification of PCR product
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Analysis of internal transcribed spacer region
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RAPDand SSRscoring and data analysis
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PCR amplification
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Running of gel and visualization of DNA
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Determination of the yield
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Agarose gel electrophoresis
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Qualitative and quantitative estimation of DNA
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Determination of the yield
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Procedure for DNA isolation
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Reagents required for fungal DNA isolationand p
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DNA isolation of Trichodermaisolate
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Photography, evaluation and documentation
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Procedurefor SDS-PAGE
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Materialsrequired for SDS-PAGE
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Protein profiling of bioagent through SDS-PAGE
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Dinitrosalicylate reagent (DNS)(per liter)
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Identificationof bioagent
Tags
- md-1-md-2
- mt-9-mt-8-mt-1-mt-2
- md-1-md-2-mt-2
- md-1-md-2-mt-3
- md-2-md-11-md-1-md-4
- md-2-md-11-md-1-md-3
- md-2-md-11-md-1-md-9
- md-2-md-11-md-1-md-10
- md-2-md-11-md-1-md-7
- md-2-md-11-md-1-md-12
- md-2-md-11-md-1-md-2
- md-2-md-11-md-1-md-1
- md-2-md-11-md-1-md-5
- mt-6-mt-6-mt-2-mt-1
- md-2-md-11-md-1-md-8
- md-2-md-11-md-1-md-11
- md-2-md-11-md-1-md-6
- md-2-md-1
- md-1-md-2-mt-1
Annotators
URL
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Bacterial strains used
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Production of Lipase
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Antibiotic resistance amongVibriofrom shrimp farm
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Extraction of genomic DNA
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Validation of the predicted 3D structure
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Phylogenetic and motif analysi
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Phylogenetic and motif analysis of sequenced Dof domains
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Gel elution of PCR products
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Validations
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Mapping of SbDof genes on sorghum chromosomes and its intron/exon gene structure prediction
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Sequencing PCR
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Minipreparation of plasmid DNA from transformed co
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Restriction digestion
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Basic requirements for PC
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DNA extraction procedure
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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The table 6.1 gives the mixing probabilities and the associated parametricvalues fork(number of components) = 2,3, and 4. It may be noted thatthe Log likelihood value is smaller fork= 4 (the results fork= 5 , 6 etc.are not better than that fork= 4 and hence are not given here). The fourcomponents Poisson Mixture model is given in table 6.2. It may be notedthat 58% of wards may have higher incidence/relative risk and the remainingwards have lesser/lower incidence for the Cancer disease. We computed theposterior probability for each component for each ward (see table 6.3). Eachward is assigned to a particular component so that the posterior probability islarger. These results are also given in table 6.3 Finally we present Choroplethmaps based on those results
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Algorithm
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Data Sources
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Poisson Model
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Spodoptera litura
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Haemolymph protein profiling
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Venomous saliva optimization
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Starvation and collection method
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Insects Collection
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Mandibular stylet
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Head and stylet preparation
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Growth maximum values
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Rates of growth (OD678/day
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Growth
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Experimental Set up
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- Jun 2019
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krishikosh.egranth.ac.in krishikosh.egranth.ac.in
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Experiment 1: Assessing the impacts of elevated CO2and N levels on yield and nutrient uptake in rice
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Temperature Gradient Tunnels (TGT)
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krishikosh.egranth.ac.in krishikosh.egranth.ac.in
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Estimation of total N% of wheat grainsand straw
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Chlorophyllcontent
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Root length (cm) and Root weight (mg)
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Coleoptile length(cm)
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Stomata / cm2
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Leaf area index (LAI)
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Physiological parameters
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Days to physiological maturity
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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T cell phenotypic distribution in HBsAgPositive, HBsAgNegative from HBsAg positive mothers and healthy newborns.
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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GFP-β-catenin T41A mutant
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.inThesis3
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Reagents
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Standard curve of ascorbic acid
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ZnSO4
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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Procedur
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Procedur
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Procedure
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Procedure
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Reagent
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Total antioxidant activit
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Procedur
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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Material
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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Total dissolved solids
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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High Performance Liquid Chromatography (HPLC) analysis
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High Performance Thin Layer Chromatography (HPTLC) analysis
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. Thin Layer Chromatography (TLC) analysis
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Preliminary phytochemical screening (Ali, 1998; Evans, 2002)
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Microbial Contamina
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Foaming Index
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pH values
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Ash values
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Extractive value
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. Physico-chemical standardization
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Standardization of ethanolic extract of E.ribes (WHO, 1998; IndianPharmacopoeia, 1996)
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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Estimation of Stevioside
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Estimation of Steviol
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Estimation of total phenols
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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Mean Somatotypes:
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Somatocharts:
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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Balanced mesomorph:
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- May 2019
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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Purity of the DNA extracted from various environmental samples was confirmed by subjecting the extracted DNA to restriction digestion. DNA was digested with Sau3AI (New England Biolabs). One μg of metagenomic DNA in 20 μL reaction mixture was treated with 0.5 U of Sau3AI and incubated at 37 °Cfor 10 min. The reaction was terminated at 80 °C for 20 min and the digested DNA was fractionated on 1.2 % (w/v) agarose gel.
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Restriction digestion
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as well as commercial methods (MN kit, Germany; Mo-Bio kit, CA, USA; Zymo soil DNA kit, CA, USA) according to the manufacturer’s protocols and compared in terms of DNA yield and purity.
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The soil DNA from Pantnagar and Lonar soil samples were also extracted by various manual (Desai and Madamwar, 2007; Agarwal et al., 2001; Yamamoto et al., 1998
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Comparison of yield and purity of crude DNA
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Various strains of Escherchia coli (DH5α, XL1Blue, DH10B) were used as hosts for the propagation of recombinant vectors. In addition, Bacillus subtilis was used as a host for the expression of xylanase gene from the recombinant vector pWHMxyl. Different vectors used in this investigation are listed in
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BACTERIAL STRAINS
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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All the peptides used in this study were synthesized by solid phase method on an automated peptide synthesizer (Applied Biosystems, Model 431A), using F-moc (9-fluorenylmethyloxycarbonyl) chemistry on a p-hydroxymethyl phenoxymethyl polystyrene resin (Nova Biochem). For the peptide synthesis, 0.1 mmol of the resin was used and deprotected using 20% piperidine in N-methyl-pyrrolidone (NMP). Subsequently 0.5nmol of the first amino acid was added and coupling was performed usmg DCC-HoBt (dicyclohexylcarbodiimide-hydroxybezotriazole) ester formation method. All other amino acids were coupled by DCC ester coupling. Amino acids and solutions required for peptide synthesis were procured from Nova Biochem and Applied Biosystems, respectively. After completion of synthesis, deprotection was carried out in 20% piperidine/DMF. Finally, the resin was shrunk using ether and dried under vacuum for a minimum of four hours. The cleavage was performed in dark using 94% TF A, 5% anisole, EDT and water accompanied by continuous stirring for two hours. The resin was then filtered and washed with DCM and the solution was evaporated on a rotary evaporator (Buchi, Switzerland) till only a small quantity of DCM/cleavage mixture is left. Cold anhydrous diethyl ether was added to the filtrate to aid in the separation of scavengers from the mixture. The peptides were then extracted with water using a separating funnel. Extraction was followed by evaporation of residual diethyl ether on the rotary evaporator. Total aqueous layer was then frozen as a thin film and lyophilized.
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Procedure for peptide synthesis
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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vector, under the phage T7 promoter, in BL21 (DE3) cells, and under the T5 phage promoter, in the pQE30 vector for expression in SG13009[pREP4] and M15[pREP4] cell strains. For cloning in pRSET B, the full length bZP3 initially subcloned in the pBacPAK8 vector at the Kpn I and Sac I sites was released after digestion with Kpn I and EcoR I and cloned in a similarly restricted pRSETB vector inframe with an N-terminal His6 tag. For cloning in the pQE30 vector, the pBacPAK8 carrying the full length bZP3 was initially digested with Not I, filled in with Klenow and then digested with Kpn I. The purified bZP3 fragment was then cloned in the vector digested with Kpn I and Sma I in frame with an N-terminal His6 tag. Though transformants positive for the bZP3 insert in the right reading frame were recovered, no expression could be detected by SDS-PAGE or immunoblots in either case. An alternate strategy was then devised in which an internal fragment of the gene, excluding the signal sequence and the transmembrane-like domain, following the putative furin cleavage site, was amplified by PCR using the forward primer 5'-CGGGATCCCAACCCTTCTGGCTCTTG-3' incorporating a BamH I site and the reverse primer 5'-CCGAGCTCAGAAGCAGACCTGGACCA-3' incorporating a Sac I site. The PCR was done in a 50 J!l volume using 50 pM of each primer and Vent polymerase for extension. The pBluescript-bZP3 (1 0 ng) having a full length bZP3 insert was used as the template and was initially denatured at 95°C for 10 min. Amplification was carried out for 35 cycles of denaturation at 95°C for 2 min, primer annealing at 600C for 2 min and extension at 72°C for 3 min followed by a final extension at 72oc .for 15 min. The amplified bZP3 fragment was digested with BamH I and Sac I and cloned in frame downstream of a His6 tag under the T5 promoter-lac operator control in the pQE30 vector. The authenticity of the construct was confirmed by N-terminal sequencing using an upstream sequencing primer GGCGT ATCACGAGGCCCTTTCG.
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Our initial attempts to express the full length gene in E. coli as a His6 fusion protein failed. Attempts were initially made to express the His6-bZP3 protein in the pRSET B
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PCR Amplification and Cloning in pQE30 Vector
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ligation reactions were carried out usmg conditions and buffers specified by the manufacturer.
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The PCR amplified eDNA fragment corresponding to bZP3 was resolved on a 0.8% agarose gel run using IX TAE buffer (0.04 M Tris-acetate, O.OOI M EDTA) and purified using the Geneclean® II kit. The PCR amplified bZP3 was digested with Kpn I and Sac I and ligated into the pBluescriptll SK(+) vector at the same sites. The digestion and
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Agarose Gel Electrophoresis, Digestion and Ligation
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shodhganga.inflibnet.ac.in shodhganga.inflibnet.ac.in
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PBS and then replenished with the complete medium. Two days following transfection, the cells were subcultured into the appropriate selective medium for selection of stable clones as described below.
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Calcium phosphate mediated stable transfections were performed by the method of Graham and Van der Eb ( 1973 with modifications as described by Gorman ( 1986 ). For each plasmid, two petri dishes each containing 0. 5 x 106 CHO-K1 cells were used, with 10 ug of cesium purified DNA for each transfection. A mock transfection which did not contain any DNA, was performed simultaneously as negative control. Precipitation of the DNA was done with great care to ensure the obtention of a fine, translucent precipitate rather than a dense and opaque precipitate. The calcium phosphate I DNA precipitate was added in 4 ml medium to the cells and the cells incubated for 3 hours at 37°C. At this stage, the cells were examined under the microscope and a fine precipitate appeared as small grains all over the cells. The cells were washed once with serum free medium and a glycerol shock given for 3 minutes at 37°C. The cells were washed twice again with
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Using calcium phosphate.
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bands seen in the DNA size marker, were marked with a ball -point pen at the places where small holes had been pierced in the gel earlier ( see above ). Thus it was easy to monitor the size of the fragments showing hybridisation to the probe. The gel was then peeled off and the membrane w~shed in 6 X sse with gentle rocking for 10 minutes to wash away any residual agarose sticking to the membrane. After air drying at room temperature, the membrane was baked at so0e for two hours. The baked filter was stored at room temperature in a dessicator, if not used immediately. The dehydrated gel was restained in water containing 0.5 ug I ml ethidium bromide for 30 minutes and examined on a short wave UV transilluminator to check for the presence of any DNA fragments that escaped blotting. The absence of any residual bands indicated that the transfer was complete.
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Restriction fragments of DNA resolved on agarose gel were transferred to nylon membrane ( GeneScreen or GeneScreen Plus by the capillary blotting procedure of Southern ( 1975 ) as described by Maniatis et al., ( 1982 ) . After the completion of electrophoresis, the gel was stained and photographed as described earlier. Position of the various bands obtained in the DNA size marker lane were marked by piercing small holes at the two ends of each band in the gel with a yellow tip. The gel was then denatured, neutralised and blotted essentially as described by Maniatis et al., ( 1982 ) . Locally available coarse absorbent paper was used to make the paper towels of the appropriate size. In case of genomic DNA from mammalian cells, the agarose gel was first treated with 0.25 M HCl for 10 minutes, followed by the rest of the procedure as mentioned above. The transfer buffer was 20 X SSPE in all cases. To prevent the absorption of fluid from the 3 MM paper under the gel directly to the blotting paper atop the nylon membrane, the gel was surrounded with polythene sheets to minimise the direct contact between the blotting paper and the 3 MM paper placed under the gel. The blotting was performed for 18 -24 hours. After the transfer was over, the paper towels and the 3 MM papers on top of the nylon filter were peeled off. The gel along with the attached membrane, was turned over and kept on a clean sheet of 3 MM paper with the gel side up. The position of the gel slots was marked with a ball -point pen. Also, the positions of the
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southern blot.
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lectrophoresed on 0.7 % -1.2 % agarose gels in TAE or TBE buffer. Choice of the percentage of agarose and the electrophoresis buffer system was made following the guidelines of Maniatis et al., ( 1982 ). In general, upto 1 kb fragments were resolved on 1.2 % agarose gels using TBE buffer. For most other purposes, TAE buffer was used. Agarose gel electrophoresis was carried out as described by Maniatis et al., ( 1982 ) . The run was stopped when the bromophenol blue dye migrated to within 1 em -1.5 em from the edge of ' the gel, except when the sample had fragments smaller than 500 bp, in which case the elctrophoresis was terminated at an earlier stage. The gel was immersed in water containing 0.5 ug I ml ethidium bromide, for 30 minutes, to stain the DNA. When detecting very low amounts of DNA, the staining was done for 60 minutes followed by destaining in 1 mM Mgso4 for one hour at room temperature. The DNA bands were visualised on a short wavelength UV transilluminator ( Fotodyne, Inc., USA and photographed with a Polaroid MP-4 camera using Polaroid type 667 film.
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DNA digested with restriction enzymes was
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ecanted and the pellet dried briefly under vacuum. The final DNA pellet was resuspended in 500 ul of TE. A 1:50 dilution of the sample was used to measure the absorbance at 260 nm and at 280 nm. The A260 and A280 values were used to estimate the concentration and purity of the sample as described by Maniatis et al., ( 1982).
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further purified by centrifugation to equilibrium in a 30 ml cesium chloride -ethidium bromide density gradient, as described by Maniatis et al., ( 1982 ) . The band corresponding to closed circular plasmid DNA was collected and further purified by a second centrifugation to equilibrium in a 6. 5 ml cesium chloride -ethidium bromide density gradient. The final DNA band collected from the gradient was extracted with an equal volume of isopropanol which had been previously saturated with TE and cesium chloride. This extraction was repeated twice to completely remove the ethidium bromide from the DNA sample. The DNA was then dialysed against one liter of TE for at least 8 hours, at 4 °c, with several changes of TE. To the dialysed sample, one tenth volume of 3 M sodium acetate, pH 5.2, was added and the DNA precipitated with two volumes of chilled ethanol. The precipitation was carried out 0/N at 0 -20 c. The precipitated centrifugation at 10, 000 rpm, DNA was collected by for 10 minutes. The supernate was carefully d
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resuspended in 20 ml of Tris -Glucose solution ( 25 mM Tris. HCl, pH 8. 0; 50 mM Glucose ) . The cells were vortexed followed by repeated pipetting to obtain a uniform cell suspension. To this, 6.0 ml of a freshly prepared lysozyme solution ( 10 mg 1 ml, prepared freshly in sterile distilled water ) was added. The cell suspension was swirled to mix thoroughly and incubated for 5 minutes at room temperature. Next, 0.5 M EDTA was added to a final concentration of 10 mM, the contents swirled to mix and incubated in ice for 20 minutes. Next, 40 ml of a lytic mix containing 0. 1 % SDS and 0. 2 N NaOH was added. This was prepared freshly by mixing 4 ml of 10 % SDS solution into 36 ml of 0.22 N NaOH solution. The solution was mixed by vigorous but brief shaking till the cell lysate became clear, followed by incubation on ice for 5 minutes. Finally, 20 ml of 5 M potassium acetate solution, pH 4.8 was added. Again the contents were swirled to mix, followed by incubation in ice for at least 1 - 2 hours. The lysate was centrifuged at 10,000 rpm for 30 minutes at 4°c. The supernate was filtered through sterilised glass wool kept in a funnel, and collected in a graduated cylinder. The measured volume of the cell lysate was transferred into another centrifuge bottle and two volumes of 95 % ethanol added to precipitate the DNA, at 0 -20 c, 0/N. The DNA was pelleted by centrifugation at 10,000 rpm at 4 °c for 30 minutes. The supernate was carefully poured off and the pellet res~spended in 25 ml of TE ( 10 mM Tris.HCl, pH 8.0; 1 mM EDTA ). The plasmid DNA was
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Plasmid DNA was isolated using the alkaline lysis method of Birnboim ( 1979 ) with slight modifications. One liter of TB supplemented with ampicillin @ 50 ug 1 ml was inoculated with 10 ml of a freshly grown primary culture and the culture incubated 0/N at 37°c, in an incubator -shaker. The cells were pelleted by centrifugation at 4000g for 10 minutes at 4 °c. The supernate was discarded and the pellet
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Isolation of plasmid DNA.
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sg.inflibnet.ac.in sg.inflibnet.ac.in
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The membranes were suspended (1.4 x 108 cell equivalent) in 250 III of incorporation buffer (50 mM HEPES, pH = 7.4, 25 mM KCI, 5 mM MgCb, 5 mM MnCI2, 0.1 mM TlCK, 1 Ilg/ml leupeptin, 1 mM ATP, 0.5 mM dithiothreitol and 0.4 Ilg/ml tunicamycin). Each assay tube was prepared by adding 12.5 III of 1 % Chaps, 2.8 III of 200 IlM GOP-Man, 10 III of GOP-[3H]-Man (1IlCi) and 25 nmol of synthetic substrate (49). The contents were lyophilized and 250 III of membrane suspension (1 .4 x 108 cell equivalent in incorporation buffer) were added to each tube. The tubes were incubated at 28°C for 20 minutes, cooled to 0 °C and the membranes were pelleted at 4 °C for 10 minutes in a microcentrifuge. The eH] mannosylated products, that were recovered in the supernatant, were mixed with 0.5 ml 100 mM ammonium acetate and applied to a C18 Sep-pak cartridge that had been washed with 5 ml 80% propan-1-01 and 5 ml 100 mM ammonium acetate. The cartridge was washed with 1.5 ml of 100 mM ammonium acetate and then the eluate was reapplied to the same cartridge. The cartridge was subsequently washed with 5 ml of 100 mM ammonium acetate, after which the bound material was eluted with 5 ml of 60% propan-1-01. The final eluate was concentrated and redissolved in 100 III of 60% propan-1-01. One tenth of this volume was taken for scintillation counting. The above assay was then carried out with a range of concentrations of OMJ to assess it's effect on the activity of eMPT enzyme parse.
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eMPT inhibition assay
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mixture was concentrated and the residue was repeatedly lyophilized to yield 7S; ESMS (mlz): 263.1 (M-Hr. Guanosine 5'-diphospho-4,S-di-deoxy-4,S-difluoro-a-D-talose mono triethyl amine salt) 77. A mixture of 4-morpholine-N,N'-dicyclohexylcarboxaminidium guanosine 5'-monophosphomorpholidate (27 mg, 34.4 Ilmol) and 7S (10 mg, 21.5 Ilmol) was coevaporated with anhydrous pyridine (3 x 500 Ill). 1 H-tetrazole (5 mg, 68.7 Ilmol) and anhydrous pyridine (1 ml) were added and the mixture was stirred under argon atmosphere for 2 days. Water was added and the mixture was concentrated under reduced pressure to afford 77; ESMS (mlz): 608.3 (M-Hr.
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6 Hz), 4.85 (1H, s); 13C NMR 853.28,65.12 (15 Hz, C3), 67.3 (24 Hz, C5), 69.72 (C2), 81.1 (JCF = 168 Hz, C4), 89.9 (JCF = 171 Hz, C4), 101.47 (C1). 1 ,2,3-Tri-O-acetyl-4,6-di-deoxy-4,6-difluoro-a-D-talopyranoside (73). To compound 72 (100 mg, 0.543 mmol) was added 2% sulfuric acid solution in acetic anhydride (1.2 ml). The mixture was stirred at rt for 90 minutes. The contents were diluted with saturated sodium bicarbonate solution. The mixture was extracted with ethyl acetate. The organic phase was thoroughly washed with water, dried over sodium sulfate and concentrated to afford 73. 2,3-Di-O-acetyl-4,6-di-deoxY-4,6-difluoro-a-D-talo-di-O-benzyl phosphate (75) : Compound 73 ( 70 mg, 0.225 mmol) was dissolved in anhydrous CH3CN saturated with dimethylamine (5 ml ) at -20°C and stirred for 3h after which TlC confirmed the disappearance of starting material. Excess of dimethylamine was removed under reduced pressure at 30°C and the reaction mixture was concentrated to afford 2,3, di-O-acetyl-4,6-di-deoxy-4,6-difloro-a-D-talopyranoside (74). To a stirred solution of compound 74 and 1 H-tetrazole (21 mg, 0.3 mmol) in anhydrous CH2CI2 (400 Ill) was added dibenzyl-N,N-diisopropylphosphoramidite (99.4 Ill, 104.3 mg, 0.3 mmol) and the mixture was stirred under argon atmosphere for 2 h at rt. Subsequently, the reaction mixture was cooled to -40°C and m-CPBA (87 mg, 0.504 mmol) was added and stirring was continued for another 30 minutes at rt. The reaction was quenched by the addition of a solution of saturated sodium bicarbonate. The mixture was extracted with CH2CI2. The organic phase was thoroughly washed with water, dried over Na2S04 and concentrated to afford 75, which was purified by running a silica coated preparative TlC plate; Rf = 0.24 (50% ethyl acetate in hexane); 1H NMR characterstic ¢ 5.67 (1 H, dd, J = 6.3 Hz and 1.8 Hz, H-1); 13C NMR: ~ 20.5-20.6 (OAc), 64.77, 64.99, 66.28, 66.43, 69.9 (24 Hz, C5), 79.96 (JCF = 169 Hz, JCH = 7.1 Hz, C6), 84.08 (JCF= 180, JCH = 5.4 Hz, C4), 95.68,126.85-128.7,169.50,169.77; 31p NMR 8 -3.03; ESMS (mlz): 551.2 (M+Nat. 4,6-Di-deoxy-4,6-difluoro-a-D-talosyl phosphate (76). To a solution of 75 (30 mg, 0.056 mmol) in CH30H (1 ml) was added palladium on charcoal (10%, 280 mg) and formic acid (100 Ill). The mixture was stirred at 50°C for 3h. The catalyst was filtered off and the solvent was evaporated. The residue was taken in a mixture of CH30H:water:triethylamine (5:3:2, 1.6 ml) and stirred for 2 days at rt. The reaction
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Methyl-4,6-di-deoxy-4,6-difluoro-a-D-talopyranoside (72). DAST (750 j.!L, 5.6 mmol) was added with stirring at -40 °c, to a suspension of methyl-a-D-mannopyranoside 62 (200 mg, 1 mmol) in anhyd CH2CI2 (4 mL). The mixture was stirred at -40 °c for another 30 minutes and then at rt for 3 h. After cooling to -200C, the excess of reagent was destroyed by addition of CH30H (600 j.!L) and sodium bicarbonate (200 mg). The cooling bath was removed, and the mixture was filtered once effervescence ceased. The filtrate was concentrated, loaded onto a silica column and eluted out with CH2CI2 to yield 72; Rf= 0.7 in 12.5% CH30H in CH2CI2; 1H NMR (CDCI3) 83.40 (3H, s, OCH3), 4.19 (1 H, m), 4.52 (1 H, d, 6 Hz), 4.68 (1 H, d,
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Synthesis of [4,6-Dideoxy-4,6-difluoro]-GDP Talose (Scheme 16 of Results and Discussion)
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mg, 0.03 mmol) in 95% aqueous pyridine (1 ml) was added. After 30 min CH2Cb was added and the solution was washed successively with cold 1 M Na2S203 (2 x 5 ml) and cold 1 M TEA hydrogen carbonate (2 x 5 ml), dried over Na2S04 and concentrated. The residue was purified by silica column chromatography (1.5% CH30H in CH2Cb with 0.1 % Et3N); Rf = 0.54 in 20% CH30H in CH2CI2; 1 H NMR: 8 -0.01 (s, 6H, Me~iCMe3), 0.84 (s, 9H, Me2SiCMe3), 1.95-2.11 (m, 18H, OAc), 3.62 (m), 3.88 (m), 4.2 (m), 4.5 (m), 4.9 (m, 2H, H-2', 3'), 5.28 (m, 3H, H-1, 2, 3), 5.44 (m, 1 H, CH=CH2); 31 P NMR .8-2.68; ESMS (mlz) : 925.3 (M-Et3N-H)". Dec-9-enyl-6-dihydroxyl-4-~-D-galactopyranosyl-a-D-mannopyranosyl phospha te triethylammonium salt (55). A solution of aqueous HF (48%) in CH3CN (5:95, 400 Ill) was added to compound 54 (10 mg, 0.009 mmol) at 0 aC. The solution was stirred at 0 aC for 2 h. The reaction was quenched by the addition of the aqueous NaHC03 solution until effervescence ceased and diluted with CH2CI2. The organic layer was extracted with water and TEAS solution thoroughly, dried over Na2S04 and concentrated to give dec-9-enyl-2,3,4-tri-O-acetyl-4-~-D-galactopyranosyl-a-Dmannopyranosyl phosphate triethylammonium salt; ESMS (m/z): 811.4 (M-EtsN-H)". A solution of oxalyl chloride (0.38 mg, 1.5 Ill, 0.003 mmol) in anhydrous CH2CI2 (50 Ill) was cooled to -78 aC and DMSO (0.47 mg, 1.7 Ill, 0.006 mmol) was added, followed by the addition of a solution of dec-9-enyl-2,3,4-tri-O-acetyl-4-~-Dgalactopyranosyl-a-D-mannopyranosyl phosphate (7 mg, 0.007 mmol) in CH2CI2 (100 Ill). The mixture was stirred for another 30 minutes and then triethylamine (10 Ill) was added. The solution was brought to rt, water was added and the mixture was extracted with CH2Cb. The organic layer was dried over Na2S04 to give the aldehyde 55. Dec-9-enyl-6-dihydroxyl-4-~-D-galactopyranosyl-a-D-mannopyranosyl phosphate triethylammonium salt (56). The residue was taken in a mixture of CH30H:water:triethylamine (5:3:2, 1.6 ml) and stirred for 2 days at rt. The reaction mixture was concentrated and the residue was repeatedly lyophilized to yield 56.
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Dec-9-enyl-2,3,4-tri-O-acetYI-[6-0-(t-butYldimethYlsilyl)-4-~-D-galactopyranosyl] -a-D-mannopyranosyl phosphate tri ethylammonium salt (54). A mixture of H-phosphonate 6 (from scheme 1, 50 mg, 0.057 mmol) and dec-9-en-1-01 (30 Ill, 0.172 mmol) was dried by evaporation of pyridine (2 x 0.5 ml). The residue was dissolved in anhydrous pyridine (1 ml), pivaloyl chloride (22 Ill, 0.172 mmol) was added, and the mixture was stirred at rt for 1 h whereafter a freshly prepared solution of iodine (6
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(Scheme 13 of Results and Discussion)
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Synthesis of S'-hemiacetal analogue90 of Gal 1,4~-Man-aphosphate acceptor
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was diluted with water and the aqueous layer was thoroughly extracted with ethyl acetate (15 ml x 2). The organic layer was dried over Na2S04, concentrated and dried to yield C4C] labelled stearyl alcohol 51. [14C]-Stearyl-2,3,6-tetra-O-acetyl-4-0-(2,3,4 ,6-tretra-O-acetyl-~-D-gal actopyrano syl)-a-D-mannopyranosyl phosphate triethylammonium salt (52). A mixture of H-phosphonate 47 (296 mg, 0.37 mmol) and [14C] stearyl alcohol (51,100 mg, 0.37 mmol) was dried by evaporation of pyridine (2 x 3 ml). The residue was dissolved in anhydrous pyridine (5 ml), adamantane carbonyl chloride (160 mg, 0.8 mmol) was added, and the mixture was stirred at rt for 1 h whereafter a freshly prepared solution of iodine (160 mg, 0.63 mmol) in 95% aqueous pyridine (5 ml) was added. After 30 min CH2Cb was added and the solution was washed successively with cold 1 M Na2S203 (2 x 10 ml) and cold 1 M TEA hydrogen carbonate (2 x 10 ml), dried over Na2S04 and concentrated. The residue was purified by silica column chromatography (2.5% CH30H in CH2CI2 with 1 % Et3N) to afford 52. [14C]-Stearyl-4-~-D-galactopyranosyl-a-D-mannopyranosyI phosphate triethyl ammonium salt (53). To a solution of compound 4 (75 mg, 0.07 mmol) in anhydrous CH30H (12.5 ml) was added anhydrous sodium carbonate (80 mg, 0.75 mmol). The mixture was stirred at rt for 2 h, whereafter sodium carbonate was removed by filtration. The solvent was evaporated and residue concentrated to yield 53; R,= 0.55 in 10: 1 0:3 CH30H:CH2CI2:O.25% KC!.
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[14C]-Stearyl alcohol (51). Stearic acid (50,100 mg) in anhydrous THF (1 mL) was diluted with C4C] stearic acid (1.2 mL, 120 !lCi). To this was added THF-borane complex (4 mL). The mixture was refluxed at 90°C for 36 h. The contents were then poured onto CH3COOH:H20 (8 mL, 1:1), taken in a separating funnel. The mixture
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Synthesis of [14C] labeled Stearyl linked Gal 1,4 f3 Man phosphate (Scheme 12 of Results and Discussion)
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Polycondensation. Compound 26 (25 mg, 0.033 mmol) was dried by evaporation of pyridine (500 III x 3) therefrom. The residue was dissolved in 10:1 pyridine:triethylamine (40 Ill), and pivaloyl chloride (9 Ill, 0.073 mmol) was added. Another lot of pivaloyl chloride (6 Ill, 0.04B mmol) was added in 45 min. After 3 h, the mixture became viscous, and a freshly prepared solution of iodine (220 Ill, 35 mg, 0.137 mmol in pyridine-water, 95:5) was added. After 2 h, CHCI3 was added and the organic layer was successively washed with cold 1 M aqueous Na2S203 solution and 1 Mice-cold TEAB buffer, dried over Na2S04 and concentrated to dryness to afford 27. For final deprotection, above residue was dissolved in 0.1 M NaOMe solution in CH30H (440 Ill), 1,4-dioxane (BOO Ill), and CHCI3 (BOO Ill). The mixture was stirred at rt for 7 h and left at 4 °C for 16 h, then diluted with CH30H, deionized with Dowex 50W-X4 (H+) resin, filtered and immediately neutralized with drops of triethylamine. The mixture was concentrated to dryness to afford fully deprotected phosphoglycans (28). 31 P (D~O): 8 -1.73, O.BB. Preliminary CD analysis of Phosphoglycans. The above polycondensation product (28) was lyophilized repeatedly and then redissolved in H20 (400 Jll). This solution was taken in a glass cuvette (300 Ill, 1 mm pathlength). It's CD spectra was recorded on a spectropolarimeter (JASCO, J-710) between 175-250 nm at 25°C. For reference, the CD spectra of agarose (15% W/V)87 was also recorded under the same conditions as mentioned above.
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Triethylammonium 2,3,6-tri-o.acetyl-4-o.(2,3,4-tri-o.acetyl-~-D-galactopyrana syl)-a-D-manno pyranosyl hydrogen phosphonate (26). Compound 6 (30 mg, 0.034 mmol) was dissolved in a mixture of acetic acid-water-THF (3:1:1,2.5 ml). The mixture was stirred at 40°C for 9 h, after which the solvent was evaporated off under vacuo at rt. To remove excess of acid, water (1 ml) was added and evaporated off twice to afford 26 in quantitative yield; 1H NMR (CDCI3, 300 MHz) 0 1.95-2.09 (m, 21 H), 3.49-3.68 (m, 4H), 3.88 (m, 1 H), 4.14 (m, 1 H), 4.36 (d, J = 4.5 Hz, 1 H), 4.47 (d, J = 7.8 Hz, 1 H), 4.95 (dd, J = 3_3 and 7_8 Hz, 1 H), 5.05 (dd, J = 2_1 and 7.8 Hz, 1 H), 5.21 (dd, J = 2.1 and 3.6 Hz, 1 H), 5.41 (d, J = 3.3 Hz, 1 H), 5.48 (dd, J = 2.1 and 7.8 Hz, 1 H), 7.99 ( d, JH,p = 637_0 Hz, 1 H); 13C NMR (CDCI3, 75 MHz) 0 20.48-20.76, 60.10, 62.42, 66.57, 69.36, 69.53, 69.69, 71.20, 73.30, 73.86, 91.59, 92.54, 101_09, 169.13-170.49; 31p (CDCI3): 00.22; ESMS mlz657.3 (M-EhN-Hr.
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Synthesis of phosphoglycans by polycondensation
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Selective cleavage of phosphoglycans from the resin. This was accomplished by taking the PG loaded resin (3 mg) and Wilkinson's catalyst (1 mg) in argon-purged solvent mixture (300 Ill, toluene-PrOH-H20, 2:1 :0.08 containing 0.01 N HCI) and shaking it for 7 h at rt. The cleavage after first cycle of coupling provided 2,3,6-tri-0-acetyl-4-0-[2,3,4-tri-O-acetyl-6-0-(t-butyldimethylsilyl)-~-D-galacto pyranosyl]-a-D-mannopyranosyl-phosphate. This intermediate was subjected to full deprotection to provide ~-D-galactopyranosyl-a-D-mannopyranosyl phosphate (25) and compared with authentic sample earlier reported86 by our laboratory; [a]D = +10° (c 0.1, H20); lH NMR (D20, assignments by 2D COSY and TOCSY experiments) 0 3.45 (dd, J = 6.67 and 1.5 Hz, 1 H, H-2'), 3.46 (m, 1 H, H-5), 3.60 (m, 1 H, H-5'), 3.53-3.56 (m, 2H, H-2,3'), 3.68 (m, 2H, H-6), 3.76 (t, J = 7.11 and 2.64 Hz, 1 H, H-3), 3.83 (m, 2H, H-6'), 3.83 (m, 1 H, H-4'), 3.94 (m, 1 H, H-2), 4.38 (d, J = 9.65 Hz, 1 H, H-4), 4.38 (d, J = 7.6 Hz, 1 H, H-1'), 5.27 (dd, J1H-P = 6.8 Hz and J1•2 = 1.9 Hz, 1 H, H-1); 31p NMR 0 -2.07; ESMS, 421.2 [M-1 Ht; HRMS (ESMS): calcd for [M-Hr C12H22014P 421.2720 found 421.2718. Similar procedure was used to cleave phosphotetrasaccharide 22 from resin followed by complete deprotection, which provided compound 23 that was characterized by its comparison with standard prepared by solution method.
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opyranosyl phosphate] triethylammonium salt (22). The butenediol-linker functionalized Merrifield resin (19, 50 mg, 0.43 mmol/g, 0.021 mmol) was swollen in anhydrous pyridine (100 Ill) for 15 min, followed by addition of phosphoglycan H-phosphonate donor 6 (26 mg, 0.03 mmol) dissolved in anhydrous pyridine (500 Ill). Now pivaloyl chloride (20 Ill) was added and the resin mixture was shaken for 2 h. Thereafter a 200 III solution of iodine (4 mg) in 95% aqueous pyridine was added and stirring continued for another hour. The resin was then thoroughly washed with CH30H (700 III x 3) and dried over P20S overnight to afford acceptor-functionalized resin (20, 50 mg). ~ The coupled intermediate was characterized by positive ion ESMS after cleaving it off from the resin (2 mg) by treatment with 0.1 N HCI (100 Ill) at 100°C for 1 min. The product that got cleaved under this condition was characterized as 2,3,6-tri-0-acetyl-4-0-[2,3,4-tri-O-acetyl-6-0-(t-butyldimethylsilyl)-~-D-galactopyranosyl-a-Dmannopyranose which was identical to compound 5, already synthesized by solution method described earlier; ESMS m/z 731.3 (M+Nat. This compound on full deprotection with 48% aqueous HF-CH3CN (5:95) and CH30H-H20-EhN (5:2:1) provided disaccharide Gal1 ,4~Man (24); lH NMR 8 5.12 (d, J = 1.67 Hz, 1 H, H-1 a), 4.85 (d, 1 H, J = 0.98 Hz, 1 H, H-1 ~), 4.40-4.36 (m, 2H, H-1' and H-4), 3.75 (dd, 1 H, H-2'),3.94-3.92 (m, 2H, H-4' and H-2), 3.89-3.83 (m, 2H, H-6'), 3.81-3.79 (dd, 1H, J= 6 and 2 Hz, 1 H, H-3), 3.75-3.71 (m, 2H, H-6), 3.63-3.59 (dd, 1 H, H-3'), 3.51-3.46 (m, 2H, H-5, H-5'); ESMS: m/z 341.0 [M-Hr. To a part of the PG loaded resin 20 (15 mg), 48% aqueous HF-CH3CN (5:95,500 Ill) was added at 0 °C and the mixture was stirred on a orbital shaker for 3 h. The resin was then washed with CH30H (500 III x 2) and dried under vacuum to afford acceptor bound resin (21) with free 6' hydroxyl groups. This intermediate was again characterized by ESMS after cleaving it off from a small part of the resin (2 mg) by treatment with 0.1 N HCI (100 Ill) at 100°C for 1 min. The product that got cleaved under this condition was characterized as 2,3,6-tri-O-acetyl-4-0-(2,3,4-tri-O-acetyl-~D-galactopyranosyl)-a-D-mannopyranose. Authenticity of this compound was confirmed by its comparison (TlC, NMR, ESMS) with standard separately prepared via solution synthesis by deprotection (HF-CH3CN) of TBDMS group from compound 5 (Scheme-1). A second cycle of PG coupling was carried out with identical procedure given above to afford phosphotetrasaccharide (22).
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and water (150 mL). The organic layer was dried (Na2S04) and concentrated. The crude product was purified by silica column chromatography (20% ethyl acetate in hexane with 1% EhN) to afford 17 (4.2 g, 80%); Rf = 0.3 in 50% ethyl acetate in hexane; 1H NMR (CDCI3, 300 MHz): <52.03 (s, 1 H), 3.68 (d, J = 4.8 Hz, 2H), 3.78 (s, 6H), 4.03 (d, J = 5.4 Hz, 2H), 5.73-5.75 (m, 2H), 6.82 (tt, J = 1.2 and 9.0 Hz, 4H), 7.25-7.44 (m, 9H); 13C NMR (CDCb, 75 MHz): 55.12, 55.13, 58.75, 59.93, 113.05, 126.68,127.76,127.99,128.95,129.87,130.92, 136.07,144.79,158.37; ESMS m/z 413.39 (M+Nat Preparation of functionalized resin by coupling of linker (19). 4-(4,4'-Dimethoxytrityl)-2-cis-butenol (17, 1 g, 2.56 mmol) was dissolved in anhydrous DMF (8 mL). Upon cooling to 0 °C, sodium hydride (60% dispersion in mineral oil, 150 mg, 3.75 mmol) was added and the solution was stirred for 1 h. Merrifield's resin (18, 650 mg, chloromethylated polystyrene cross-linked with 1 % divinylbenzene, Fluka-63865) was added along with tetra-butylammonium iodide (95 mg, 0.256 mmol) and shaking was continued for an additional hour at 0 °C after which the reaction mixture was brought to rt and shaken for another 12 h. The capping of unreacted sites on resin was accomplished by addition of CH30H (100 ilL) and sodium hydride (100 mg) and shaking the contents for another 4 h, after which more CH30H (5 mL) was added and the resin was washed sequentially with 1:1 CH30H: DMF (10 mL), THF (10 mL x 3) and CH2CI2 (10 mL x 3). The resin was dried over P20s under vacuum to afford 836 mg of the linker-attached resin (19). To quantify loading8S of linker onto the solid support, a stock solution of 3% TFA in CH2CI2 (10 ml) was prepared which contained effectively 0.167 mg of the protected resin. The resulting orange colour liberated by the release of dimethoxytrityl (DMTr) cation was measured by UV at 503 nm, and the loading of the linker onto the resin was calculated to be 0.43 mmol/g of resin. The deprotection of the entire DMTr-linker functionalized resin was then carried out by treating the resin with 1 % TFA in CH2CI2 (10 mL). Further washing with CH2CI2 (20 mL x 3), 1% EhN in CH2CI2 (10 mL) and CH2CI2 (10 mL) and drying under vacuum afforded 640 mg of deprotected resin ready for coupling with phosphoglycan donors. Solid Phase Synthesis of 2,3,4-Tri-O-acetyl-~-D-galactopyranosyl-(1 ~4)-2,3,6-tri-O-acetyl-a.-D-mannopyranosyl phosphate 6-[2,3,4-tri-O-acetyl-6-0-(t-butyldi methylsi lyl)-~-D-galactopyranosyl-(1 ~4 )-1 ,2,3,6-tetra-O-acetyl-a.-D-mann
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Synthesis of SOlid-phase linker, 4-(4,4'-Dimethoxytrityl)-cis-2-butenol (17). To a solution of cis-butene-1,4-diol (16, 4.7 mL, 5 g, 56.7 mmol) in anhydrous pyridine (100 mL) at 0 °C was added 4,4'-dimethoxytrityl chloride (6.4 g, 18.9 mmol). The reaction mixture was gradually brought to rt over 3 h and stirred for additional 12 h. Ethyl acetate (200 mL) was added and the organic phase was washed with water (150 mL), saturated aqueous NaHC03 (200 mL), saturated aqueous NaCI (200 mL)
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Solid phase phosphoglycan synthesis
Tags
- Method-2-Method-1-Method-2
- Method-3-Method-2-Method-1
- Method-5-Method-1-Method-2
- Method-2-Method-1-Method-3
- Method-2-Method-1-Method-2-detail
- Method-2-Method-1-Method-3-detail
- Method-3-Method-1-Method-2-detail
- Method-3-Method-1-Method-2
- Method-3-Method-2-Method-1-detail
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- Method-4-Method-1-Method-2-detail
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