Science topic
Silk - Science topic
A continuous protein fiber consisting primarily of FIBROINS. It is synthesized by a variety of INSECTS and ARACHNIDS.
Questions related to Silk
I am working on silk nanofiber for preparation of wound healing patches
Here's an example, Francois Quesnay's economic table. As a doctor, Quesnay sees the
economy as a huge organism, and the precious economic surplus is like a blood supply function
vital to life. To explain this view, he made the first economic "model" (model), a simplified economic map. Quesnay created it in his original book, The Economic Table (Economic chart). He outlined many curves to represent the resources circulating around the economy. The peasants produced the economic surplus and paid the rent to the nobles who owned the land, who then bought the silk buttons and the silver candlesticks from the hand craftsmen. The craftsmen in turn bought food from the farmers to complete a cycle. The economy is a kind of surplus circulation formed between the peasants, the landlords and the hand craftsmen.
This economic table can be written as the following program diagram:
Farmers' production and economic surplus→Pay the rent to the nobles who own the land→The nobles then bought silk buttons and silver candlesticks from the handcraftsmen→The craftsmen in turn bought food from the farmers.
We are trying to make Silk fibroin and PVA blend solution in formic acid for electrospinning but it is not miscible. I tried following
1. I tried to dissolve both in 99% formic acid but the solution wasn't look proper for electrospinning.
2. I also tried to mix the both by dissolving individual in formic acid.
3. I also tried to mix by dissolving silk in formic acid and PVA in water.
In all three cased i didn't get the homogeneous solution for electrospinning
Dear members of the community,
I am trying to elaborate silk fibroin. I boiled the silk for 30 min. Then, when it is dry, I cut it in small pieces and dissolved it with 9.3 M Libr solution (I put 5 mL of solution for every 1 g of silk fibroin).
Then it put it at 60 º for 4 h and at that point I manege to dissolve the silk. Sometimes I have to gently stir with a spatula since otherwise there are some parts of silk on the surface that will not dissolve . After the 4 h I obtain an amber solution with black beats and also bubbles. Also, it seems like there is not 100 % solution, it looks like some parts are a bit gel. Is it normal?
Then, I put this solution into a membrane to dialysis at 4 º but it gels during the process. I put the string bar at the lowest and I change water after 1 h 4 h 6 h and then every 12 h. The whole process takes 48 h. When I add the water it is at room temperature shall I cool it to 4 º before conducting the change?
I read several solutions like boiling the silk for 45 min, adding more LiBr solution or one more concentrated, increase the oven temperature to 80 º. What solution would be the best? Am I missing something?
Thank you in advance for your help,
Enric
Dear colleagues,
I want to simulate the maize grain number with 6 level temperature stress experiments by APSIM-MAIZE. I have tried to modify the temperature fuciton from the default value (8, 34, 44℃) to a modified value (5, 30, 41℃), which concluded from Wang (2018).But, the simulation was not good for grain number.
Thus,
(1) how to modify the temperature function with my heat stress experiments?
(2) what's the calculation formula for maize grain number in the Maize Module?
in addition, my phytotron controlled-temperature experiment were conducted with 6 temperature from 30 to 40℃ during maize silking period.
I have been encountering challenges in my Nematology work especially when using Galleria mellonella (Greater Wax moth) as a bait to Entomopathogenic Nematodes. The larvae will produce silk that helps it to enter the pupal stage without getting infested by Entomopathogenic nematodes in the soil sample. How do we control the silking to enable easy penetration and subsequent infestation by Entomopathogenic Nematodes?
How should the maximum temperature be measured for new composite materials made of silk and epoxy?
New composite materials from silk and epoxy material
What number of days to 50% silking can be used to predict the maturity of maize? for example early maturing verities may have a range 56-63 days to 50% silking.
I am running a degradation study on dissolving silk in a formic acid calcium chloride system and I was wondering why the solution turns from clear to a darker purple/black that darkens over the course of a week. Does anyone have any ideas on what chemical reaction is occurring that is causing the solution to turn purple? I've included images of my solutions, the first solution was degrading for about 30 minutes and the second for a couple weeks.
I'm working on an aquatic insect that produces silk and I would like to know if every silk has a composition of fibroin (highest percentage) and sericin. Thank you!
I'm following the instructions here to create a 3D printable bioink but after i freeze dry my samples, they only partially dissolve in water. I tried heating with a stir bar too and it would still not completely dissolve. In the paper, they describe their Sil-MA composite as a powder after freeze drying but my sample is more similar to a strong Styrofoam. I cannot grind it up with a mortar and pestle and cutting it is very difficult. I've had relative success dissolving it in formic acid but but i think the acidic environment hinders crosslinking so I'd perfer to use water as the solvent instead. Any ideas?
The data is attached below. Please give me technical advice!!
Wondimagegne A Mo Deconvolution of a composite peak into its individual peaks plays an important role in the interpretation of many types of graphs including XRD, XPS, FTIR, and PL etc. In this video, I have discussed how to deconvolute simple combined peaks, composite peaks and how to correct missing data in a given peak with the help of deconvolution. In the case you want to further ask about it, please do comment on the specific video, I'll respond to it shortly. I have provided the practice filee (OriginLab) here. Thanks
Hello,
I'm working on the flowering of maize, and more particularly on ASI. This year i would like (for my job) to make a selection in the objective to reduce ASI. But I didn't find any informations about how to do in litterature. Could you help me please?
Thank you very much
We are looking for edible fibers that can be used in the food industry
does silk fiber edible? And does the FDA approve?
Many thanks for considering my request.
In most cultures, traditional textiles use natural dyes, unbleached materials and white cotton/ linen/silk which is beautifully synchronized with the concept of sustainable living. In today's fast-fashion scenario, how many people prefer/use undyed materials.
I have some question about the laboratory process of extraction silk fibroin from Bombyx mori base the Prof. Kaplan protocol. How much Silk cocoon need for 20 experiments? How dialyzes the final product? How long can I keep Silk ّFibroin? Thank you for your responses in advance.
Hi all - a puzzler for you. We're using the protocol detailed at https://www.nature.com/articles/nprot.2011.379 to extract and isolate silk fibroin from silkworm cocoons. In brief, you boil 5 g of cocoons in 0.02 M NaCO3, wash the matted silk fibers in H2O, and then dissolve in 9.3 M LiBr.
Some people in our lab find that after dissolution in LiBr, they get a pale gold solution (roughly the color of a lager). But some people get a rose gold/pink solution. If you move on to the dialysis steps later, you eventually see the pink fade to the normal pale gold. Anecdotal evidence suggests that if you do a better job washing, you are more likely to get the pink, and pink solutions tend to be slightly more acidic.
Any ideas why this is happening? In my naive understanding, colors tend to mean pi bonds...there are a large number of tyrosine residues in silk (288/5,525), some tryptophans (13/5,525), and some phenylalanine (37/5,525). Silk is also especially prone to assembling into beta sheets--though the point of dissolution is supposed to be disrupting those.
Possibly also relevant: these solutions are normally made in house DI water, not 18 MOhm water.
Is there any simple chemical analysis method, by which the removal of outer sericin protein layer from raw silk fibers (after de-gumming) can be confirmed?
There are techniques likes weight loss, FTIR, FE-SEM, XRD, SAXS, Contact Angle, DSC, & TGA, for the confirmation (I have tried these techniques).
But, I want to know about any simple chemical analysis method, which can help in confirming the removal of sericin protein layer from de-gummed silk.
Thank you.
Kind regards,
Prakash
During inspection of #maiz found one plant grown as lower half part of #tassel and upper half part as #silk at terminal region. This is the first time I have seen...It looks amazing to me.
I need to know the heat and moisture production of any silkworm larvae period for supplementary heat.
I am doing Immunocytochemistry (ICC) to detect vinculin on hWJ-MSC which seeded on silk scaffold. I want to know perfect time to fixate the cell (start the ICC protocol) so that i can observe vinculin on fluorescence microscope.
The Belt and Road Initiative (BRI), also known as the One Belt One Road (OBOR) or the Silk Road Economic Belt and the 21st-century Maritime Silk Road, is a development strategy adopted by the Chinese government involving infrastructure development and investments in 152 countries and international organizations in Europe, Asia, Middle East, Latin America and Africa.
The BRI is twelve times more than the Marshal Plan. Do you believe this initiative will change the world? Is your country joining this initiative? Why do you think the BRI is good or bad for your country?
Hello,
I have to build up a new calcium imaging system which has 340nm and 380nm LED´s (should be very new on the market). When I load my cells (e.g. mouse neurons from DRG´s or recombinant cells) with Fura2 (3µM for 45 min. incubation) I get nearly no signal. What I noticed is, that my baseline starts at a very low ratio (~0.05). I have rowdatas of 500 at 340nm wavelength, and 8000 at 380nm. Normally the baseline is between 0.6-0.9, isn´t it? I also have an older Setup with an arc lamp. There I normally have rowdatas of 150 at 340nm and 200 at 380nm. Could it be that my intensity of the 340nm is too low? Or is the 380 nm too strong?
Does someone knows what my problem can be? I´m grateful for any idea!
Thank you!
Silke
How to get rid of the insect from the pupae (Silkworm) because the silk yarn is very strong and need any parts of the mouth and not the absorbent pipette as the butterflies?
Preprint About China and OBOR
China's economic and technological growth has made it a global power with geopolitical impact across Eurasia. The country borders on 14 states and has a direct maritime border with three others (Japan, Philippines, South Korea and Taiwan - not recognized as an independent state).
In this sense, the Belt and Road Initiative is not only a plan for building infrastructure but a broad vision for the future of Eurasia integration. This strategic vision comprises geo-economic elements and is based on geopolitical factors. The ability to move forward with the values and ideals that surround the initiative will be essential for its consolidation.
I have used 9.3M LiBr solution to dissovle silk fibroin according to nature protocol at 60oC, and the ratio is 1g:4ml. But silk is not soluble completely so i can't use the solution. Can you give some ideas or where was i wrong?
I have been following your researches, because they cover partly my area of scientific research interest? The international trade was mainly reorganized during and after the second World War, although ancient times and afterwards long colonial history shaped trade paths that remained as a heritage of the trade roads.
Since 2015 I have been deeply analysing the Belt and Silk Road Initiative and the AIIB establishment (already in 2015 as a competitive solution to TPP Trade Deal of the US and 11 other Pacific Rim nations). Unfortunately TPP was abandoned by US and is being revamped, now. (The TPP part is not my strength)
More important from my point of research is to find out the key expansion goals of China or rather empirically verify my thesis about long term process of internationalization, which in my perception is the final stage of China's attendance in globalization - mean World supremacy.
I am not judging positive and negative aspects of that process, at least at this stage, but I am trying to verify macroeconomic drivers of such decisions, apart from political once. In my opinion the New Silk Road project, supported by various financial means (solely Chinese or more complex international), due to its scale is comparable with the Marshall Plan that created Western countries' economies after the Second World War and which set economic global connection, existing till present times.
The second part of my scientific research is focused more towards the AIIB itself and perspectives of its role, towards internationalisation of RMB, at least in investment settlements and then in trade once. The ultimate question is whether China wants to internationalize RMB and if yes whether its economy is ready for that. This question is important in relation to the establishment of clearing offices around the World and relatively tiny share of RMB in trade deals clearance. Most of them is cleared in USD.
Bearing the above in mind I would like to ask you the following questions:
1. What are the main goals of your project: "International trade"?
2. Are you planning to utilize gravity model?
3. What scope will it have? Asia-Pacific Rim?
4. Are you in the process of setting up a team? I would like to participate.
Nagano sensei, how can I help you with your Silk article?
AJ Jacobs
For a study I need to solve silk cocoons...
after degumming them in boiling NaHCo3 for 1 hour, we used the trinary solvent (CaCl2, H2O,C2H5OH ) during 4 hours and heated to 60 c ...silk cocoons didn't solve completly....how much does it take to dissolve them compeletly!the changes after 4 hours are so negligible....!what should I do?Have we ignored sth?
Here I mentioned only Glass rod and silk cloth. This can be anything from triboelectric series. But, why should it happen? Why should different charges accumulate in two materials and then neutralized again when coming into contact? Why can't the charges gaining energy when rubbed get distributed in the same material itself? And, how this phenomenon happens in insulators?
I wanted to known how much percent of silk protein is forming particle in the system.
eg. If I add 5% of silk protein in acetone then how will find how much particle is formed .
And how would I able to separate unreacted one.
Can anyone suggest me a cheap source of silk cocoons in Pakistan? I need to extract silk fibroin from it.
While preparing Silk solution from degummed silk fibroin by the LiBr method, I am finding that my solution is solidifying in the dialysis step or upon storage at 4 degree. In case it is not solidifying, white thread like materials are emerging which cannot be removed upon centrifugation at 1100 rpm for 20 mins.
We've just found an amount of silk without any notification of whether it is just silk fibroin or fibroin+sericin combination. Although it looks like cotton wool, we wanna be sure that it doesn't contain sericin.
thanks in advance
I have observed two silk work cocoons (which look like tasar silk worm cocoons) on an eucalyptus tree in my clonal trial at Navsari, Gujarat. The cocoons were collected from 12 m height. Has anybody observed such cocoons on eucalyptus? Is there any earlier reports?
I obtained silk from bombyx moori after lithium bromide treatment. The aqueous solution I get solidifies when I try to mix the drug in it using magnetic stirrer which is very difficult to use for electrospinning. How can I get rid of the problem?
I have been using PBL for two decades now. Two things struck me in the goups randomly assigned to work together. I wrote about this extensively in the endnotes section in my book on TE Education since it is something of a hobby horse of mine. The process of using this teaching strategy, even in large groups, is explained fully ther
The group might be dysfunctional for various reasons but usually the two reasons I gave above in the question predominate though I tried to minmise them by randomly assigning group leaders for each group.
I also encountered both problems mentione above during my elearning course, and frankly found the ostracising one much more disturbing personally.
I never liked giving group assignments as an assessment strategy; the PBL presentations were a simple teaching strategy to engage students with learning and further reading as required at HE level.
Once I was constrained by student demands to give them the option of doing an assignment in pairs. If done in pairs both students had to write a small reflection on the whole process. Reading the reflections, everything was as smooth as silk, which made me sceptical of course.
Come a year later I learnt how the assignment was done by one person while the other did the assignment of the other study unit in a couple of instances; so much for the reflective account..
With regards to group assignments allocated by other academics, I had heard too much hoary incidents by students confiding me, to even remotely consider it, hence my duo students effort.
We use Galleria melonella for toxidity-tests in our lab. I am breeding them by myself, but it's disturbing, that they always producing silk and spin a cocoon. (If you buy them in a pet-shop, they don"t). So does anybody have an idea, how to stop G. melonella from producing silk?
Silk waste can be felted. Can the waste from bamboo silk also be felted?
My question is how I can protect myself and my colleagues against the toxins Thaumatopein, because I get very large allergic reactions on my skin?
Could someone tell me, can I do insolation od silk fiber on other way?
I'm posting the nest of Thaumetopoea pityocampa Schiff .
I'm currently working on my Supply chain management dissertation and I need some research question on the New silk road's logistical and transportation process.
Silk fibroin is a well-known biodegradable material, and there are hundreds of publications about the usage of silk fibroin in tissue engineering, wound healing, drug delivery etc. However, silk sutures are non-absorbable (non-degradable), as indicated in the suture selection guides of all the suture manufacturers.
So... is silk fibroin degradable or not? If it is degradable, why is it used for the non-degradable sutures?
I'm on a low budget, which is why i opted for urea because it is supposed to reduce the hydrophobicity of the fibroin protein, but so far I've achieved nothing with it.I In my last attempt, I dipped the two cocoon silks in 9.3 M of urea for 4 hours at a temperature of 60 degrees celsius. Any suggestions? Thanks in advance.
I need spectral transmission characteristics of textiles (materials for clothes) in spectral range (380-1500) nm, and a little less for UV. Especially I need transmission characteristics for: tosilk, cotton, wool, linen, hemp fiber, viscose fiber, bamboo, acrylic, nylon, polyester, polyamide, elastane.
I am going to extract silk fibroin and make scaffold (HFIP sponges) of it. Now in the article that I am following, u need to lyophilze the silk solution through freeze dry method but I don't have freeze dry facilty so can I use vacuum lyophilization instead. Your valuable suggestions will be highly appreciated please.
The chinese government released a test guideline namely, "Test guidelines on environmental safety assessment for chemical pesticides—Part 11: Silkworm acute toxicity test"
The guideline I got from Internet is in Chinese language. If anybody having the English version of the guideline, please share with me.
Thanks
Hi everyone,
I've been interested in spider silk lately. There is a question that puzzle me for a while.
While mainstream papers underlines the advantages of spider silk over other materials (like steel and nylon), few of them mentioned the comparison between spider silk and other insect silks(like silk of silkworm). My question is : is spider silk outperform other insect silk as biomaterial (specially biomaterial for engineering). If yes, how?
Thanks,
Guangqi
Mostly cotton fabrics are used in medical field apart from that what is the main advantages of using silk, polyester or blended silk/polyester fabrics?
I'm working on wolbachia bacteria to study it's antiviral activities in silk warm cell lines. However, I'm not finding the source of bacteria to purchase. Can anyone help me regarding this?
I have performed uniaxial compression testing for the silk based scaffolds in dry state with varying parameters! The results which i have obtained were less compared to the same test performed for wet scaffolds(reported in a literature). Is there any reason for it?
mainly for b. mori silk. sericin is a gummy substance which is soluble in hot water. Then why there is need to treat with chemicals like soap solution, sodium carbonate etc.
I am trying it by LiSCN but could not get the proper dissolution.
i am looking for challenges and sustainable solutions in Kenya
I guess 20X PBS will do this by literature.
Tenacity of the silk yarn is one of the important inherent characteristics of the silk yarn needs to be preserved in processing. Silk is the only filament yarn which is subjected wet to processing treatment several times before it is converted into the fabrics Viz Crepe, Georgette Chiffon Taffetta , soft silk Doupion etc . Each fabric has different handle and lustrous Effect
As described that silk mats were sterilized by spraying 70% ethanol. I want to know whether it effects on the activity of growth factor that are co-spun with silk fibroin. Also can we sterilize the mats under UV radiation?
Generally, In silk engineering, we use organic solvents to induce beta crystallinty! I read few papers mentioning autoclaving as a viable technique to induce 60% beta sheet crystallinity which is far better than organic solvents!! May i get the suggestions on the time required to autoclave ,say 3cm X 2 cm, scaffolds to induce secondary structure? Experimental setup, How to autoclave the scaffolds?????
awaiting your kind reply!!!
I work with a fibers of wild silk, fineness 1,07dtex, strength 26,90cN/tex, elongation at break 34,25 CN/tex. In hot water fibers are melt.
My problem: 200 caterpillar working nest, I need to make insulation of fibers.
Manual isolation is uncertain because it destroys the fiber.
Is there any chemicals (aqueous or oily base) that the fibers would not melt and allowed me the insulation fibers?
what are the catalysts required??
I have done diaotization of light chain silk for modification of tyrosine present in it. I tried H1-NMR and ATR-FTIR on these modified silk. But no peak was observed, from dizonium salts in both of these characterization, Is there any technique to determine that silk material is diotized and %diaotization done after completion of experiment?
By using plasma treatment on the silk fiber the Carbon decreases and oxygen increases. Is it hydrophobic or hydrophilic?
I have seen various articles regarding the major amino acid source is glycine and alanine in case of silk fibroin from B.mori. I would like to know about the possibility of the residual functional groups in the fictionalization of our fibroin with other polymers? Are there any ways?
I'm trying to measure the porosity of some silk scaffolds I made. From some papers I read, they did a hexane displacement method to measure the porosity. Part of the methodology states that they did a quick evacuation-repressurization cycle to completely evacuate the pores from air and replace it with hexane. Initially, I thought of using the vacuum oven. However after reading the MSDS of hexane (toxic, flammable), I now have second thoughts of doing this. Can anyone suggest an easy and safe way of performing an evacuation-repressurization cycle? Is just any vacuum pump compatible with this?
I want to soluble completely silk fibroin. Suggest me solvent that will completely solubilize silk.
A literature search yields that the size of sericin protein isolated from cocoon of silk worms ranges from 20-400 kDa in SDS-PAGE. The number of bands can be attributed to the reducing effect of SDS, but what is its molecular weight?
I am planning to study the surface properties of different types of natural silk fibers by plasma treatment.
I am working on silk based small diameter vascular graft, for that I need to stick the inner layer to stick on the mandrel.
I'm looking for the very first description of a silk producing Arthropod, most likely it was a spider. Don't get me wrong I'm not looking for a description of a species, we know today it produces silk.
So the very first description people noticed was a "spider" that was producing silk and maybe build a net - something like that.
I hope somebody can help me!
LCA is cradle to grave analysis of embodied energy. This is an environmental and energy related topic studied in an inter-disciplinary approach. Textile fibers and textile products attracted early attention, but studies of such kind on silk are rather scarce.
