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- 2Could anyone suggest a storage buffer solution for Zymography gel?
I would like to store it in simple solution but I couldn't remember. Please let me give an advice.
Thank you, Cristina!Following
- 2Which element types are used for the buckling analysis of truss elements in APDL and which results can be obtained ?
i want to do buckling analysis of truss but LINK did not give buckling .
So need urz guidline
I fully agree with the method suggested by Mr.Naveen Bhatt. Buckling is essentially a bending process which requires beam elements for modelling. Truss or LINK elements lack the bending capability. However, to simulate the overall truss behavior, the joints have to be coupled in displacement dofs. Also, the support conditions also should have only displacement dof.
- 6Can somebody kindly explain how to remove polyphenolics from peptide fractions?I am presently purifying some bioactive peptides from processed soybean only to realise it is contaminated with polyphenolic compounds from the bean. I will appreciate a concise answer on how these polyphenolic contaminants can be removed from the fractions.Following
- 1Is anyone aware of any studies (even unpublished) checking on hyperactivity-inattention with the SDQ quest on Anorexia Nervosa children/adolescents?
SDQ = Strenghts and Difficulties Questionnaire
You may be already familiar with these articles:
- Using the Strengths and Difficulties Questionnaire (SDQ) to screen for child psychiatric disorders in a community sample by Robert Goodman.
- Eating disorders in children and adolescents. First results of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) by H. Hölling & R.Schlack. [Article in German].
- 1Could you please give me an advice which QD stabilizer can make QDs stable in DMSO?
Hello. Could you please give me an advice which QD stabilizer can make QDs stable in DMSO? Cysteamine - coated QDs are unstable. Thank you!
Try NOBF4. It works as in the enclosed paper - we tried it, but did not mention it there.Following
- 27What is the proper way to analyse the T-RFLP data?
Currently, I haveT-RFLP raw data. I have used Mica3 to export all of the genera. I used three enzymes to digest my samples. Could you please give me some suggestion on how to further analyse them? Which software should I use to do which kind of analysis? If possible, could you please give me the examples?
Thank you very much.
Dear Dr. Blaud,
I used T-Align online tool to perform the bar chart. Yes, you are right. There are too many TRFs to feed into one bar chart.
I read your paper again and would like to ask some questions:
1. after the T-Align, I got three files. Which one I should use to check and remove the TRFs (<0.5%)? The comparison one or the consensus one (see the attachments)?
2. Once I found there is a area% <0.5 in any one of the 4 samples, I will remove this TRFs? Is it correct? After this, the profile of the TRFs for each sample will be changed. Then I need base on the remains to recalculate the % to make it up to 100% within one sample? But how to do it? I only have the %, do I need go back to check the input file to find the peak area points for these TRFs and then re-calculate it?
3. After all of these (if I got a correct understanding), I will have a file that is the "Data from the TRFLP matrices" mentioned in your paper?
4. Then the square root transformed and similarity matrices were constructed using the Bray-Curtis method.
5. Then Similarities between samples were displayed using non-metric multi-dimensional scaling (nMDS) plots and dendrograms
Sorry to bother you and many many thanks!
- NewHow public sector organisations deliver strategic goals and agreed outcomes from their allocated financial resources?
this is through balance sheet management in the public sector,Following
- 3Could you provide reference of researches about educational programmes that use eye-tracking, psicogalvanic response and think-aloud techniques?
Could you provide reference of researches about educational programmes that use eye-tracking, psicogalvanic response and think-aloud techniques to analyse their relation with educational results?
Not a specific reference about think-aloud, but a technical one about eye-tracking: The Pupil Eye tracking Platform: http://pupil-labs.com/ have been a great open source tool for the studies I am running.Following
- 1Hello, I am working on building the predictive analytics model for diabetes. For that, I need dataset. Can anyone help me please?
Currently, I am working on building predictive analytics model to predict early diabetes by comparing healthy person habits and symptoms with diabetic patients.There will be few other components of my prediction (that I can not share right now) I am certain that my model and algorithms will work perfectly and provide an accurate result. As you know, data is an important part for the accuracy of the model. Therefore, I need the dataset for training and testing of my model. I have already built the concept and mechanism to provide real time prediction. I would appreciate if someone can help me getting the dataset that includes good amount attributes.
Consider contacting the ACCORD trial investigators which is randomized, multi-center, double 2 X 2 factorial trial in 10,251 patients with type 2 diabetes mellitus.
The website is https://www.accordtrial.org/public/index.cfm
Which predictive model you wanna use and what are you trying to predict exactly? good luckFollowing
- 1Why do some long chain molecules (in this case MPEG-SH) prefer to attach itself to the end of a nanoparticle (nano-rod) where the curvature is higher?
I am following the method published in this paper (link: http://pubs.acs.org.libproxy1.nus.edu.sg/doi/suppl/10.1021/cm101155v).
Why do some long chain molecules (in this case MPEG-SH) prefer to attach itself to the end of a nanoparticle (nano-rod) where the curvature is higher, while the shorter chain molecules (CTAB) prefers to attach to the side where it is more flat.
In general, the system tries to minimise its surface energy by adsorbing ligands that result in the minimal energy. I'd suspect it is just a steric effect: since mPEG-SH is blukier at its "tail" than CTAB, you get better coverage on a curved surface.Following
- 1Why is my ammonium sulphate protein precipitation not working properly?
I started with partial purification of amylase using ammonium precipitation technique.While going for step by step saturation the recovery of protein was less than 10% of the crude amylase.So i started with 20ml crude enzyme direct 100% saturation.The precipitates were dissolved in 500ul of phosphate buffer and poured into dialysis bag,dialysis bag was dipped in phosphate buffer.After 24 hours there were crystals in the beaker contain buffer. I changed the buffer and kept for another 24 hours yet another day i see the crystals in the beaker This process continued for a week. After a week also some crystals were seen in the beaker but i startet with the protein estimation. I was expecting atleast 80% recovery but again i got only 12% recovery.....the quantity of protein had also increased from 500ul to 1ml
The volume increase of the sample was due to the sample having a higher osmolarity than the dialysis buffer.
I would guess that the crystals are ammonium phosphate, although this is not consistent with the high aqueous solubility of that salt. If your sample had a lot of magnesium or calcium, the crystals could be the phosphate salts of those ions. In any case, as Viktor Butnev said, a different dialysis buffer is warranted to avoid the crystallization. Many other buffers are possible. Ammonium bicarbonate is useful for mass spectrometry, or when the sample is to be lyophilized, because it is volatile. Tris or HEPES are often used for general purposes.
Since you are not fractionating by ammonium sulfate precipitation, maybe you should just skip this step.Following
- 2For oral administration to rats, what solvent should I use to disperse my formulation uniformly?
My nanoparticles are coated with chitosan and the freeze dried nanoparticles are not able to be dispersed in water. It forms some flakes, which is impossible even to suck through the needle.
Thank you! Are their any references for this?Following
- 3Does anyone know a method and protocol for peptide fractionation and purification by column chromatography?I need to know the protocols for peptide fractionation and purification by column using Sephadex or DEAE, and also the eluent for getting various active peptide fractions for FPH (fish protein hydrolisate).Following
- 4Any advice on the switching mechanism? The file is attached here.
I have a question regarding gradual I-V curve in ReRAM. Actually the Top and bottom electrodes are Au and ITO, respectively. The insulator is polymer but I got gradual curve, what should be the inferred switching mechanism considering that Au is not an active electrode? In log-log plot it shows ohmic contact with slope of 1.2, but I think it shouldn't be filamentary because the change is not abrupt.
Would you please give me a comment?
If you are getting some characteristics like the characteristics of device I have attached here then I may help you.because the I-V you mention in the 3rd graph is current density Vs voltage. I possible kindly let me know the I-V with current vs voltageFollowing
- 2When do biogas digesters start to produce biogas?
i made an experiment in 4 l digester with inoculum 10% V/V, the digester produced biogas in the first week but other researchers say its not possible to produce before about 21 day, any one have an explanation?
mesophilic about 40 C, total solids 10% , cow dung mixed with rice straw, C:N ratio close to 30:1Following
- 6How to control the selectivity of a heterogenous catalyst?
Is there any specific method which can control the selectivity of heterogenous catalyst?
You can find out the factors that affect reaction selectivity by your experiment or others' paper.and then you can synthesize you catalyst with controlling those factors.Following
- NewCan anyone help in getting piezoresponse force microscopy (PFM) testing?
I do have thin film samples with thickness of 200 nm to be characterized by PFM.The samples were deposited on Si substrates. Can anyone extend a helping hand?Following
- 6What is the origin of graphene oxide fluorescence?
I wonder if the fluorescence of GO is associated with some by-products of its synthesis.
hi dear/ read this article..
- NewHas anybody used Netsuite as part of their accounting IS class?
Would like to know how you integrated your coursework with Netsuite AcademyFollowing
- 3Could be performed an meta analysis for uncontrolled studies?
Traditionally, the meta analysis perform between two groups (predictor variable) to identify which group or technique has better or worse than another but sometimes we need to assess an technique, method, and material without presence of comparative studies. Thus, could we do a meta analysis for case series or uncontrolled studies.
Yes, Even unpublished research can be included and optimally research from different languages and from around the world to ensure generalizability and lower the chances of bias.Following
- 19Why bacterial cells were not sonicating properly after a long duration of sonication?I have used BL21 DE3 for expression. After overnight induction at 16°C, I have harvested the cells and sonicated at 40% amplitude for 30sec on/off for several cycles, but still my cells not lysing properly.
Lysis buffer: 50mM Tris(pH 7.40),150mM NaCl,Triton X-100 1%,Lysozme and Dnase (50 mg/ml stock each),10mM PMSF, 5mM DTT,2% Glycerol.
Can anyone suggest the reason why it is not sonicating properly?
You can confirm cell lysis by two ways:
1. The suspension turns transparent. The turbidity goes down. If you don't add sufficient DNaseI it also turns dense due to the release of genomic DNA.
2. You can observe the sonicated cell suspension under microscope and guess the % of cell lysis.
Another factor that affects cell lysis due to sonication also could be the stage of cell. Stationery phase cells need harsher conditions than log phase cells.Following
- 99+Should we hold people accountable for their mistakes?
Dear RG friends,
This is an important matter, for me as researcher and as human being. It is about errors and we know: "Errare humanum est, perseverare-diabolicum".
Human errors and the adverse events which may follow, are problems of psychology, systems thinking, behavioral sciences and engineering (in technical systems). Understanding, predicting, and modulating human performance in any complex setting requires a detailed understanding of both the setting and the factors that influence performance. The social cognition research on cycles of accountability clearly captures the complexity of the effects and demonstrates the naïveté of the belief that improving society only requires holding others accountable.
The “culture of blame” never worked. Why don't people just follow the rules, legislation, procedures?
My starting point in formulating this question was occupational and system safety, but I would like to have your (expert or personal non expert opinions) in a general sense of human accountability in various fields, activities and situations?
I'm glad that Fairouz, Fadel, and Hanno again shed some light on the responsibilities of leaders (including high officials) in this thread of discussion. As humans, they are prone to make mistakes, but, like others, they should hold themselves accountable for their actions.Following
- 2Does anyone know how to do the intermolecular as well as intramolecular rotation at different temperatures?
Can you please help me to do dft calculation for rotation of molecule for a wide frequency ranging in the broadband dielectric area for different temperatures?
You should use the reaction coordinate method in which you change an angle in increments and calculate the energy. The DFT calculations are in 25 C. There is no dynamics calculations using DFT. You can use Arrhenius equation to find the rate or energy barrier at different temperatures.
The answer by Emil is also right.Following
- 4Is there a safer alternate to chloroform for killing wild adult mosquitoes collected using standard collection methods?
Most of our entomological collection methods involves adult mosquito collections and storing them dry in silica-filled tubed for processing in the laboratory. However, recently due to safety concerns, we have been advised to cease the use of chloroform to chloroform-kill the mosquitoes before morphological identification and storage. Are there other safer alternatives to use? Any relevant literature on the subject is greatly appreciated.
Thank you for all your responses, they were very helpful. Freezing mosquitoes is a very promising alternative, however we mostly conduct our studies in rural areas, most of which have no access to electricity therefore we cannot freeze mosquitoes. Ethyl acetate and CO2 are also possible alternatives we may use. Realistically speaking, from our perspective as a developing country where most services are unreliable, it may be a bit difficult logistic wise, especially with transportation of these chemicals (DG status), timely delivery etc etc.
Are there any other alternatives currently used in the field that is portable, non-DG and effective with little damage to mosquitoes?Following
- 3Which is the best method for preparation of protein hydrolysates and bioactive peptides from aquatic animals?
As per the literature, aquatic animal protein hydrolysates were prepared and evaluated for various bioactivity, but most of the protein hydrolysates were prepared by peptic enzymatic digestion and isoelectric precipitation. I wanted to know in this two methods, which will be the more easiest and most effective method to get protein hydrolysates in larger quantity.Following
- 3Can limited intensity of leguminous weeds e.g. Vicia spp., Lathyrus spp. & Convovulus help in controlling lodging in high potential cultivars?
My opinion (experience). Depending of intensity and moment of interaction between the weeds and the crop, weeds increase lodging in cereals. I worked with wheat and barley in south Brazil- if the competition/interaction occurs in beggining of crop cycle, the crop stiolate and present a slow developement of roots (because the priority is aerial part), favouring future lodging. Othervise, if high-density vetches grow at late, they use the cereal as support, and literally can bring down the plants because of their weight. Here we crop barley and wheat with 17cm between rows, and this problems I cited can occur on high weed densities.Following
- 7Is the high content of sugar in the extract that may interfere in the TBARS assay?
is that the high content of sugar in the extract may act in the TBARS assay? because i tried to evaluate the antioxidant activity of date fruit using this assay but it doesn't work.
Please consider the following points:
(i) MDA in living systems is generally a product of lipid peroxidation;
(ii) Lipids peroxidation is (generally) directly proportional to reactive oxygen species (ROS);
(iii) ROS are generated due to oxidative stress (to the best of my knowledge all abiotic stresses lead to oxidative stress);
In light of above, lipid peroxidation is a measure of oxidative stress.
Yes, I certainly agree that anything (be it be plant extract) that inhibits/reduces lipid peroxidation is an antioxidant,
We can certainly, plot a perfect standard curve by making different levels of MDA (if available) react with TBA. But, if you want to measure the potential of plant extract to inhibit lipid peroxidation (that results in MDA production), how can one get rid of MDA?
Point that we need to address is the way we can get rid of sugars from date palm fruit extract or can we have a protocol alternate to TBARS assay?Following
- 3Can I carry out immunohistochemistry on mouse tissue when the mice have been previously injected with evan's blue?
I would like to use evan's blue to assess blood brain barrier permeability in my Alzheimer's mice, but I would like to know if the same tissue can be processed for DAB or fluorescent immunohistochemistry using Iba1 or GFAP primarys, for example.
Worth noting evans blue will show in the red channel if you are considering doing immunofluorescence.Following
- 5Is it possible to compute a covariance matrix with unequal sample sizes?
I'm not sure if this question is correct, but is there a way to construct a covariance matrix for two vectors that have different lengths? If so, how?
And would it have a size of (m+n)×(m+n) (assuming the two vectors are of length m and n)?
(25* 5) * (5*25)
sampath, look at it like this. what you have is two groups of data of unequal sizes. what you are trying to do is to establish association between these two groups. in statistics group statistics are mainly dealt through t statistics, anova etc. you can look for weighted techniques, ancova etc.
another concern: service quality causes mo or mo causes service quality?Following
- 9What is the maximum drying temperature for foods?Is there any limit to call drying or another process?
Safe drying temperature depends on the type of materials. For example, plant-based materials can be dried in such temperature that does not break cell wall drastically. However, it may make higher drying time.Following