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  • Arved Lompe added an answer in Carabidae:
    Is someone interested for Coleoptera from Serbia?

    During my field studies of water- and saproxylic- Coleoptera of Serbia I regularly use some non selective methods for attracting and collecting beetles (light traps, baited traps, pitfall traps…). Usually I separate all beetles from samples, including  the representatives of families that I am not interested. The separated material I conserve and pack; mainly in paper cylinders but also in 70% alcohol. Over time, a large number of individuals and species (Carabidae, Staphylinidae, Aphodidae etc…) were accumulated.  I am ready to provide this material to interested researches for further study. In return, I am not asking for anything. Only the list of identified species for my database.

    Arved Lompe

    Dear Garbor,

    I'm interested in Trechinae (Carabidae) and can help with Determination of Carabidae (also small ones).

  • Ernst-Hermann Solmsen added an answer in Zoology:
    Is there recent konowledge about social structure within a litter of warthog piglets?

    Young warthogs (Phacochoerus aethiopicus) display suspicious light colored bristels at their cheeks. In our view these seem to mimic the prominent tuskers of the adult...(?) I would greatly appreciate to learn about the specific (or even interspecific) function in social (or Camouflage) context - arguing that the hairy Imitation of tuskers may play some role in social interaction between piglets.

    Just an idea; could anyone add some facts? The first glance upon literature (Somers et al,1995) does not deal with this character...

    Ernst-Hermann Solmsen


    Thanks a lot - that is one of the only three informations about social life in warthogs I found so long  - welcome to the Club! 

    But perhaps someone will look after now?

    Greetings to South Africa,


  • Bijaya Malla asked a question in MirBase:
    How to know if new miRNA is listed in miRBase database?

    How to know if new miRNA is listed in miRBase database (http://www.mirbase.org/)?

  • Aarthi Venkatesan asked a question in Finite Fields:
    How to compute finite field cosine transform matrix?

    i am trying to compute FFCT matrix (8*8)using modular arithmetic operation now i got correct matrix element in odd no of rows but my even no of rows all getting wrong ans .please any one knows how to compute this help me soon 

  • Sophiaa Maa asked a question in Attachment:
    Who can tell me somewhat free program for building periodic structure?

    If you knew, please attach the address.

  • Julian D. Reynolds added an answer in Amphibians:
    Do you have any idea for alien fish eradication (Lepomis gibbosus, pumpkinseed sunfish)?

    We tried many unsuccessful techniques to remove alien pumbkinseed fishes from our places. Maybe wrongly, we used net, electrical fishing, hooks. The only success was the heavy technique of drying a water pool. Use of piscicide may be a problem on a protected place, but please share your expertises and good idea. This sunfish threaten many rare amphibian larvaes and invertebrates .

    Julian D. Reynolds

    Hi David, I visited Le Pinail some years ago and I remember the many small pools that characterise it, and its populations of white-clawed crayfish - I hope they are still there, without alien species. Human interference is the main reason for spread of alien species, and pesticides may be your only answer for the sunfish, but I would recommend trying a fine-meshed seine net drawn through the pond several times. Best wishes, Julian Reynolds

  • Roger L Redondo added an answer in Hippocampus:
    Can anyone recommend good articles or reference of stereotaxic coordinates of a brain region in different age mice?

    I am injecting AAV cre into the dorsal hippocampus in 4-5 week old mice. The coordinates I have are -1.5mm [AP], 1mm [lat], 1.5 mm [ventral]. However these coordinates are for adult mice, and I want to inject in 4-5 week old mice. I'd like a reference point to where I should first try injecting for the dorsal hippocampus. 

    It would help me if there was a paper that did stereotaxic injections in young, and adult mice and what the coordinates were for those two mice. I had a difficult time finding a paper that had this.  

    Roger L Redondo

    Some companies have software that automatically corrects atlas. They rely on Bregma-Lambda distance. http://robot-stereotaxic.com/motorized-stereotaxic-instrument/

    (disclosure: I'm not associated with that company in any way). 

  • Chieng jin yu added an answer in Antibodies:
    What are the causes of Transient Hypogammaglobulinemia in an adult?

    I recently came across a 60 year old lady who had been treated for HCV infection. She was documented during evaluation to have low serum immunoglobulins and the Immunoglobulin profile showed low IgG (312 mg/dl, normal being 700-1600), low IgM (30.5 mg/dl, range 40-230) and IgA (< 50, range 70-400). She did not have chronic diarrhoea, nephrotic syndrome or cirrhosis. Her LFT and RFT were normal. She gave no history of having consumed steroids or being given rituximab. Her CD4 and CD8 counts were normal.

    A repeat test , 2 weeks later, showed normalisation of gammaglobulins level. Is it purely lab error or could there be some explanation for this phenomenon? 

    Chieng jin yu

    Interesting senario...

    First at all, may I know why the Ig levels were offered to her? Do you worried of Autoimmune hepatitis? Does she has any other immunocompromised illness, such as HIV and Epstein-Barr virus? Haemophilic status?

    Pathophysiology of hypogammaglobulinemia:

    (a)Conditions that cause an abnormal loss or increased catabolism of Ig:
    Nephrotic syndrome and other severe renal diseases
    Severe burns
    Protein-losing enteropathy
    Intestinal lymphangiectasia

    (b)Conditions/factors affecting Ig production
    Nutritional due to malnutrition or alcoholism
    Drugs e.g. phenytoin, carbamazepine, immunosuppressive drugs
    Malignancies, especially haemato malignancies
    Rheumatological disease, e.g. rheumatoid arthritis or SLE
    Viruses including HIV, Epstein-Barr virus, rubella, cytomegalovirus

    HCV with low Ig levels - we should think of:

    -HCV Related Cryoglobulinemia

    -HCV Related Lymphoproliferation

    -Drug induced, e.g. rituximab

    Few articles did mentioned about the relationship between low Ig levels with Hepatitis C:

    IgA deficiency is a risk factor for HCV infection in some patients - IgA deficiency associated with chronic hepatitis C virus infection. A cause or an effect?
    by Ilan Y et al. Arch Intern Med. 1993 Jul 12;153(13):1588-92.

  • Ritumbra Manuvie added an answer in Family:
    What are the factors that motivate migrants to repatriate the remains of their dead to the origin country?

    I am working on a project to find explanation as to why most migrants and sometimes transnational families prefer to bury their dead in origin countries. what could be behind their choices? Sometimes you find that the said migrants can barely afford a decent living in the host country but when one dies they sacrifice everything to repatriate the remains.

    Ritumbra Manuvie

    Aware this is an old question and probably you have answers by now. Among Hindu it is a belief that the ashes of the dead ones must be immersed in holy rivers for a fruitful journey into next life or towards salvation. In the country not every river is holy, but the main ones are. The ceremony must be performed at the 10th day after death. A lot of non-residents with north-Indian background (roots) therefore come to the banks of river Ganges and do this ritual.

    Also each region has their keepers of family records(the designated family priest), and ideally all the Hindu's get their family records of the deaths and births in the family updated during such visits. These family are the only source of evidence in court of law to prove family ties during any ownership and asset division cases. As India did not have any system to record the family-tree and relationship status of its population, the family records kept by the designated family priest are really useful in establishing rights on property. And normally all Hindu families are aware of this subconsciously. 

  • Zeraoulia Elhadj (www.arctbds.com) asked a question in Twins:
    About the twin prime conjecture?

    This question is concerned with this paper: https://www.researchgate.net/publication/282665260_On_a_sub-sequence_defining_twin_primes

    I am not sure that the solution is true. But I am seeking comments if any to improve the paper.

  • Zuyun Liu asked a question in SAS:
    Mendelian randomization analysis tools?

    Is there anybody who is familiar with mendelian randomization by using SAS or R? The SAS commond is syslin and the R package is sem. Thank you very much.

  • Thierry W. LEVI-FAICT added an answer in Hip Surgery:
    How can we reduce the possibility of loosening of the artificial joint after hip surgery?

    We know that after hip surgery some parts of the artificial joint is separated because of the load pressure and immune defense cells  secrete toxic substances to destroy foreign bodies .this  material absorbs most of the bones in the place of joint and weakens the connection .it causes the second surgery.so how can we reduce it?

    Thierry W. LEVI-FAICT

    Fully agree with you for this important point. I don't have any answer either except for some biological or inflammatory conditions...

  • Sun Yung added an answer in Manipulation:
    Could an incubator be sufficient to study hypoxia impact on cell features (proliferation, differentiation, senescence...) ?

    I would like to study the impact of hypoxia on my stem cell population features (proliferation, differentiation, phenotype, senescence...). Could an incubator be sufficient (with manipulations at passages under normoxic conditions), or is it required to incubate and manipulate cells under hypoxia for these investigations ?

    Sun Yung

    A hypoxic incubator is ok but not ideal because obviously when you remove the cells for media change and passaging you will be doing this under normoxia as Patrick correctly stated.

    If you have the budget, you should go for a Hypoxia workstation such as the SCI-tive (see link below). They may have one which you can borrow if you can come up with an attractive collaborative proposal.

  • Robin Dahling added an answer in Teacher Stress:
    Has anyone come across studies investigating the relationship of teacher cooperation and teacher stress/strain (at schools)?

    Are there (widely acknowledged) models and (international) studies in this area?

    Thank you!

    Robin Dahling


    I'm doing research into this field right now as it pertains to TEFL teachers in China. Found some great articles that you may find useful. Check out Combating the Downward Spiral, particularly pp 161 - 176 which looks at teacher relationships. The section on teacher collaboration was really eye-opening for me.



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  • Vanessa Pinto added an answer in Cell Culture:
    Has anyone used 2-mercaptoethanol in their cell cultures?
    Under what conditions is it required? Does it actually do anything?
    Vanessa Pinto

    Dear Dorothy,

    Thank you soo much for your attention, this will help me a lot.

    Just one more question please. For 10mM or 20mM stocks, do I need 1x or 10x sterile PBS ?

    Best regards

  • Marie-Hélène Abel added an answer in Virtual Reality:
    Is there anyone interested in a research collaboration towards 2-3 publications on the theme of VIRTUAL REALITY AND IMMERSIVE WORDS in Academia?

    I am researching the impact of these technologies to new learning systems in academic settings

    Marie-Hélène Abel

    Dear Miltos,

    My colleague Domicile Lourdeaux works in this area. You could contact her at domitile. Lourdeaux@utc.fr

    Best wishes


  • Natalia D Kreshchenko added an answer in Evans Blue:
    Can 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.

    Natalia D Kreshchenko

    Sure, you can do it

  • Alessandro Ferrarini added an answer in Lidar:
    Where can I find out about the algorithms of counting trees with airborne LiDAR ?

    i'm trying to find these algorithms. help me please.

  • Julian D. Reynolds added an answer in Food Webs:
    Does anyone know of any studies comparing simultaneous responses of both littoral and pelagic lake food webs to whole lake nutrient additions?

    I have some data demonstrating an interaction between limiting nutrients (total phosphorous) and littoral habitat (aquatic vegetation cover) on littoral invertebrate and fish abundance in lakes. I am thinking this interaction may be due to different responses of food chains (littoral versus pelagic)  to added nutrients but I am unsure of where to look for similar information in the literature. 

    Julian D. Reynolds

    Hi Corey

    No doubt you will receive many helpful answers - this topic has received a lot of attention, including in the Canadian ELA, and there are ongoing studies in a number of institutes. I just wanted to mention the classic studies of Hall, Cooper and Werner in the 1970s, adding nutrients and manipulating food webs in a series of fish ponds - to my mind laying the foundations for such studies.  Best wishes, Julian Reynolds

  • Srinvas Sharma Gangaraju added an answer in Turbulence:
    What is the critical reynolds number for turbulent transition of R134a and formulea to calculate Re no for 2 phase flows?

    What is the critical Reynolds number for turbulent transition of R134a and formula to calculate Re no for 2 phase flows?

    Srinvas Sharma Gangaraju

    Hi suresh,

    I look at this situation to be more simple than complicating the situation. As it is internal flow with phase change between throttle valve ( or any other expansion device) to evaporator, the estimation of fluid flow properties gives you reynolds number. again it is not so simple because of flash ( vapour ref associated with liquid refrigerant after throttling) specific heats during self boiling is not defined.  So the focus should be Macroscopic Approach of thermodynamics and estimate what is the associated pressure drop if the vapour refrigerant is vented with liquid refrigerant. This drop in pressure associates with accelerating flow as it tends to move towards decreasing pressure gradient. So a correction factor can be evaluated for velocity term in reynolds number ( You can give it a name also). Now the flow for a short distance would be developing flow than developed flow where reynolds number id dependent on length of the tube rather than diameter also. So one more correction factor interms of (x/L) would do some contribution to improving the reynolds number for phase change fluids.

    But all for same this area is fantastic and thought provoking. Such situations arise very often in Thermal systems.

    All the best.

  • A. S. Vishwanathan added an answer in Microbial Biofilms:
    Would a biofilm on anode of a microbial fuel cell impede transfer of electrons from microbes in the anolyte?

    As the microbial biofilm develops, would it not block access of the anode to other microbes that are suspended in the anolyte?

    A. S. Vishwanathan

    How do I tackle the issue of the biofilm becoming thicker? Is there any method to make the older bacteria detach from the biofilm?

  • Prashant Battepati added an answer in Pulpotomy:
    What is the most common medication used in pulpotomy? and which one would you think is the best one?

    What is the most common medication used in pulpotomy? and which one would you think is the best one?

    Prashant Battepati

    I agree with Alain, Formocresol is known to cause Nasopharyngeal carcinoma. But the reason behind it is inhalation of formalin/formocresol fumes in high quantities for relatively longer period, the possibilities of which is rare in dental practice moreover the volume of formocresol used by dentist is extremely low. But theoretical risk still exists. So the carcinomas associated with formocresol in dental practice is a debatable topic and fortunately there is no such reported cases in the history of dentistry where any direct relation is attributed. In India formocresol is still being widely used for pulpotomy of primary teeth. But now as we have many better options one can choose other alternates.

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  • Sarfarazhussain Farooqui added an answer in Transposons:
    How do I induce a specific mutation in a gene construct for creating a knock-in mouse model?

    Hello, as a behest for the university we have to create a transgenic knock in mouse with a specific deletion of lysine 210 in the TNNT2 gene, which causes the development of dilatated cardiomyopathy. I was able to design a genetic construct which allows me to create a knock-in model for this gene. But now I have no clue about inducing the mutation in the specific exon. I read on the internet that a mutation can be induced by radiation, chemical agents and transposons. I hope one of you can help me with a way of inducing this deletion of lysine in the gene.

    With kind regards,


    Sarfarazhussain Farooqui

    Gregory Dressler  is right, follow the crispr cas9 way and you will see the wonders. this is so far the cheapest and most easiest way of generating targeted mutations. Just one improvement: use cas9 protein (NEB etc supplies it) and Sg RNA , mix it put it at 37 degrees for 15 min and than put it on ice and inject. you will get great results with less off targets and more survivability. Good luck

  • Shuu'ichirou Yamamoto added an answer in Electrical Measurements:
    How can I expose the bottom electrode of ferroelectric devices for electrical measurement?

    I have deposited ferroelectric films on platinized wafer using spin-coating technique. How can I expose the Pt layer as bottom electrode for connection? Is there any techniques?

    Shuu'ichirou Yamamoto

    It is difficult to answer precisely due to the lack of information.

    To expose the electrode, “etching” techniques are usually used.

    Dry etching and Wet etching are two major categories.

    Dry etching technique: RIE (reactive ion etching), ICP (inductive coupling plasma), Ar ion milling, etc.

    Wet etching technique: dipping to an acid or alkaline solution. To etch oxide ferroelectrics, HCl, HF, and HNO3, or their combination can be usually applied.

    To use chemical reaction, we should know the material to be etched and also should know the precise and whole structure and fabrication process of the films on the substrate.

    Of course, we should know the sample size and the top electrode pattern.

    How do you plan to characterize the ferroelectric films?(What are the measurement method and the equipment you have)

    Most easily to get exposed area which is not fine pattern on a bottom electrode, you will wipe the spin-coated film by a solvent “before” sintering it. After the sintering process, you can deposit a top electrode just on the remained area.

    Anyway, you can find information of desirable techniques for you by searching the combination of above keywords and the material you want to etch.

    Good lack!

  • Natalia D Kreshchenko added an answer in Tissue Preparation:
    How to do tissue preparation for confocal microscopy?

    I have mouse lungs fixed in 4% paraformaldehyde and am unsure how to prepare them for confocal microscopy. I'm looking to do a quick check if the Alexa Fluor 680-labeled nanoparticles within the lungs are still fluorescent (these samples are a couple years old though). Do the lungs have to be embedded in paraffin first, or could I just slice the raw tissue and somehow mount it to a slide?


    Natalia D Kreshchenko

    You can place samples in 10% sucrose in PBS or directly in Tissue Tec for some days at 4 degree abd then freese its slowly in cryotome in embedding solution (Tissue Tec which is the same OCT )!!

  • Chirag Pallan added an answer in Domain Analysis:
    How does modes in vibration is been taken in time frequency domain analysis?

    hi all,

     while considering time domain vibration analysis of continuous structures how many modes participate in that? Does all mode is been taken in consideration?

    if so, then while doing frequency domain analysis how does this all modes can be taken in to consideration?

    also i want to know that in vibration, is it necessary that all the mode is been excited under the applied load(random or harmonic)?

    please help me in understanding this points, if possible some related reference 

    Chirag Pallan

    in my case sources of vibration are ocean waves, current, and vortex shading.

    can you please elaborate you answer?

    or can you suggest some reference


  • Arti Hansda added an answer in Bacteria:
    Hallo, all researchers here, please help me can you give me some article about nifH gene bacteria?

    Hallo, all researchers here, please help me, can you give me some article about nifH gene bacteria?

    Arti Hansda

     Hiiii Sri....just go through the links



  • Hatirarami Nezomba added an answer in NO2:
    What is the best method to determine mineral nitrogen in a soil sample?

    What is the best method to determine only the amount of mineral nitrogen (NH4, NO3, NO2) but not of organic nitrogen in a soil sample? (or the other way around?)

    I was thinking a reduced Kjeldahl might do the trick, but will I run into problems when omitting the digestion steps?

    Hatirarami Nezomba

    You can extract the mineral N using 1 M KCl and then determine NH4+-N colorimetrically using the modified endophenol method, and NO3-N using the cadmium reduction method. Adding the two (NH4-N and NO3-N) will give you the mineral N content of the soil

  • Hamit Serdar Başbuğ added an answer in Thrombophlebitis:
    What are the pros and cons for high ligation and stripping with phlebectomy for acute superficial vein thrombosis in patients with varicose veins?

    According to our experience there is not any significant difference in outcomes (rate of complications, rate of recurrence, level of patient satisfaction, QoL) between surgery for uncomplicated varicose veins and superficial thrombophlebitis. Moreover, this approach seems to be more cost-effective comparing with one month anticoagulation with LMWH or fondaparinux, followed by elective surgery or saphenous ablation.

    Hamit Serdar Başbuğ

    Dear Dr.Casian, first of all, it is hardly possible to diagnose venous insufficiency in thrombophlebitic veins, as the lumen is filled with the inflammation! An obliterated lumen is unable to be evaluated for sufficiency! Apart from this, thrombophlebitis is an inflammation having systemic extend as well as local effects. An operation over an inflammation (or rarely a possible superposed infection) is meaningless. As Dr.De Maeseneer explained in details, medical therapy should be conducted first. A need for operation should be re-evaluated after the recovery. Besides, it can also be impossible for you to push the stripper forward through the thrombophlebitic saphenous vein!

  • Alain Celzard added an answer in Activated Carbon:
    What are the effective methods of differentiating two kinds of 'Activated Carbon'?

    I'm researching on activated carbons based on their n-butane performance and hence i tried finding the physical properties but it didn't help me differentiating them. I tried finding Micropore volume with DA method, pore size Distribution with NLDFT, Surface area with BET. After carrying out the tests with the help of Micromeritics BET Equipment, I didn't find any singnificant differences to differentiate them physically. But ultimately both the kind of carbons have different n-butane adsorption capacities. Is there any possibility that they might be  chemically impregnated? if yes, how can it be found out, chemisorption equipment?? I thank you all in advance for the possible Solutions and your valuable time.  

    Alain Celzard

    Please explain what you mean by relevant / not relevant. Your question is unclear as I don't know what mean relevant or not relevant results. I am not able to provide any answer without more detailed information.