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  • Leyla Tekul added an answer in Personality Development:
    How does being bilingual affect a person's identity?

    As language and culture are intertwined, I was wondering how a bilingual person develops his/her cultural identity.  Does the person acquire the culture of L1, or that of L2?  I'd appreciate your opinion.  

    Leyla Tekul · University of British Columbia - Vancouver

    I still think a sort of acculturation must have happened to me when I was being raised and exposed to European Languages.Today, I consider myself a Eurasian, having most of the European values, and "cultural subsystems" as mentioned above.My Turkishness or let's say  regional , local characteristics  only show up in my temperament and some sudden "interjections" Thankfully, my Turkish students in Canada, only trying to learn English, without necessarily "Canadianise or North-Americanise themselves. (I am teaching Business English and interestingly, we are covering the topic Cultures and Business etiquette across cultures this week :) From a teacher's perspective though, it is very difficult not to teach the language  and some "do's and don'ts" and certain values, traditions, idioms etc without introducing the "culture" which might have created them.Today, I was trying to explain to my multicultural class the idiom "we get on like house on fire" to which none of the students could relate. How could a terrible burning house describe the closeness of a relation.I might be wrong but after a brief discussion we came to thinking that 'wood' , being the preferred construction material in this part of the world might have created this idiom. since wooden homes(which are not easily to be found in other countries' might not "catch fire" that easily. I might have been wrong with this inference but it should be difficult to deny the relation of language with  the culture which has created it.

  • Gayashan M. Arachchige added an answer in Fish Taxonomy:
    Can anyone identify these marine fish species?

    These marine species were photographed during the field works. I have identified most of them but I some doubt on identifications. So I would like to have your identification too.. Thanks

    Gayashan M. Arachchige · Wayamba University of Sri lanka

    Dear Melissa,

    I have taken these photos from rocky coastal areas of Sri Lanka.

  • Adam B Shapiro added an answer in Ribosomes:
    Does anyone have experience with spindown assays with ribosomes and some of its assoicated proteins?

    I am wondering about how one could quantify the amount of protein that co-sediments with respect with amount of ribosomes that sediments.

    Adam B Shapiro · Entasis Therapeutics

    With a densitometer, it is possible to make quantitative measurements of Coomassie Blue-stained bands on SDS-PAGE. You could compare the staining of the non-ribosomal protein band to the staining of a ribosomal protein band in the same lane in order to compare the relative amounts of non-ribosomal protein to ribosomes. If you don't have access to a densitometer, you could use a fluorescent protein stain and use a transilluminator with quantitation software, or a fluorescence scanner.

  • Ahmed Mohamed Abdelbaki asked a question in Proteins:
    Please help ,I am new in immuno precepitation how can i design my experiment ?

    ,I have protein and its antibody and i want to know if it is attach with another proteins or not 

    I will use for My protein only .

    1- can i use IgG  as a negative control ? 

    2- running gel  ? 

    3- staining with Coomassie Brilliant Blue 

    4- destain 

    5-send to mass spectroscopy

    should i see band for my protein and other different proteins?

    what should i do if i didn't see band for my protein  ?

  • Veni Bharti asked a question in Neurodegeneration:
    Is there molecular biomarker of neurodegeneration?

    molecular biomarker of neurodegeneration in cell line

  • Taufan Wiguna added an answer in Sequence Stratigraphy:
    Is it useful to apply sequence stratigraphy to a clastic alluvial fan of Quaternary only for the uppermost 100 meters (available wells data)?

    The aim of that is to define stratigraphic surfaces and to predict clay distribution.

  • Justin Krilow added an answer in Bats:
    Does the bat wing ecomorphology and structure differ between reproductive state and non-reproductive state or between female and male?

    I am curious if the wing ecomorphology of bats change/differ between reproductive stage. Example, the female bats carry additional load during flight in period pregnancy and post-pregnancy unlike of the males. Previous studies report that body weight affect wing ecomorphology (as well as flight). Thank you.

    Justin Krilow · University of Lethbridge

    You nailed it.  In Sturnia lilium, wing shape (assessed using both traditional and geometric morphometrics) differs among males, females and pregnant females.  The relationship between GM differences in wing shape and aerodynamics is murky outside of the insect literature, where it remains hand-wavy.  However, in this case, differences in wing shape as assessed through TM are associated with decreased wing loading and more manoeuvrable flights among pregnant females vs. males and non pregnant females.



  • Govinda Sharma added an answer in Quantitative RT-PCR:
    What is the purpose of using log base 2 when looking a fold change of EGFP/average tdTomato?

    This question is regarding a figure I have attached.

    Is the purpose of using log2 to better represent the idea of EGFP expression doubling? If they were to use log10 then each fold increase would be 10 fold increase as apposed to a doubling like they have done?

    Govinda Sharma · BC Cancer Agency

    fold change = 2log2(fold change)

    If I understand your question correctly, all you do to convert log fold-change into fold change is to raise the value to the power of whatever base logarithm was used.

  • Adam B Shapiro added an answer in Enzymatic Catalysis:
    Is enzyme activity the rate of reaction?

    I am trying to determine kinetic constants for my reaction. I have the enzyme activity in IU/ml. The unit of activity indicates one micromole of product formed per unit time. If we have to plot v vs S and calculate vmax and km, then do we plot enzyme activity vs Substrate conc (in micromoles)???

    Adam B Shapiro · Entasis Therapeutics

    A Unit of of enzyme activity may not have much meaning in terms of the kinetic constants Km and Vmax. The Unit is defined as the amount of enzyme required to produced a certain amount of product in a certain amount of time under specified conditions. This definition does not require that this amount of product be formed under initial rate conditions, which is a requirement for the usual method of measuring kinetic constants. Moreover, the Unit measurement is made at a single substrate concentration, whereas the usual method of measuring kinetic constants requires that measurements be made at several substrate concentrations.

  • Marc M. Abitbol added an answer in Oviducts:
    Chicken oviduct epithelial tissue preparation for cryosectioning and IHC?

    Can I make fresh chicken oviduct epithelial tissue blocks in  OCT, then snap freeze in liquid nitrogen and store at -20C? Will this affect the results of Immunohistochemistry?

    Or I should fix the tissue first in 10% NBF and then do the above process?

    Marc M. Abitbol · Hôpital Universitaire Necker

    First Fix PFA 4% in Phosphate Buffer PH 7.4 ,0.1M  overnight then Cryoprotect in Sucrose 30% in Phosphate Buffer PH 7.4 ; 01 M overnight.  then


    you should freeze gently in a hard plastic or metallic mold containing tissue tek (OCT) (like those used in pathology) at the surface of  a bath Bath of isopentane at -25°C --30°C (or use  Snapfrost excilon)

    Then you can Keep your tissue for a long time if you wish at -80°C

    then cut at the cryostat at 10 Micrometers and dehydrate the slides with the tissue sections  with increasing alcohols 50%, 75% , Absolute alcohol  (5', 5' , 5') then Dry the slides and keep them in a freezor  at -80°C or -20°C until use

    - alternatively after the sucrose step you freeze your specimen in OCT as indicated above

    Then You cut with a cryostat  between -20 and -22°C at 10 Micrometers  of Thickness

    and you keep your tissue sections at -20°C in an adequate box in a freezor

    - Otherwise use a  paraffine Protocol with an automatic system for all the steps before embedding in Paraffine and cutting with a cryotome at 5 micrometers

    You will generally obtain a better histology .

  • Houssem Eddine Ben Messaoud added an answer in Supercritical Fluids:
    CO2 Supercritical fluid phase diagram ?


    I've been looking online for CO2 suopercritical diagram by the IUPAC publication but did'nt find anything. 

    Can you please help ? if you have a copy of the diagram (entropy , pressure, temperature...) (not a must to be an IUPAC publication) .


    Houssem Eddine Ben Messaoud · Laval University

    Mhummm I tried Google .. even the IUPAC site I didn't find what I am looking for !

  • Elizabeth K Pritchard added an answer in IPP:
    What models exist for optimal interprofessional practice in rehab? How do we know/measure/evaluate optimal IPP?

    I am looking for any work done in rehab in the field of Interprofessional collaborative practice. I am especially interested in organizational supports/structures/systems as well as patient outcomes related to IPC.

    Elizabeth K Pritchard · Monash University (Australia)

    Explore the work done in NZ by Kath McPherson

    Working and learning together: Good quality care depends on it, but how can we achieve it?
    Authors of Document McPherson, K., Headrick, L., Moss, F.

  • Mohamad Akbari added an answer in AutoDock Vina:
    Is it necessary to do an MD simulation after docking?

    I used AutoDock Vina to dock a substrate (a carbohydrate) into an enzyme active site (a carbohydrase).Is the resulted complex structure (enzyme-substrate) reliable for the analysis of binding site? Or is it necessary to do an MD simulation after docking before using the complex structure for the analysis? What is actually the purpose of performing MD simulation?

    Mohamad Akbari · Damghan University

    Hi dear

    With out any ...

    I would recommend you read bellow paper,I’m sure that you find your solution.

  • Sudhir Singla asked a question in Legumes:
    Why does rainfall at maturity reduces seed yield of crops, especially of legumes ?

    why does rainfall at maturity decreases seed yield of legumes,  when pods are near maturity.

  • Mahmoud Zouaoui added an answer in Social Responsibility:
    What are the new models of social responsibility?

    Anyone researching on new models in specific or cross cultural context?

    Mahmoud Zouaoui · University of Manouba, Tunis, Tunisia

    Three main models of CSR:
    - The pyramid of CSR: four levels of CSR (A. B. Carroll, 1979):
    . Economic responsibility
    . Legal responsibility
    . Ethical responsibility
    . Philanthropic responsibility
    The total CSR of business comprises these four levels as distinct components.
    - The intersecting circles (IC) model of CSR (M. S. Schwartz and A. B. Carroll, 2003): three overlapping domains of responsibility presented in form of three circles: economic, legal, and ethical responsibility.
    - The concentric-circle model of responsibility (CON), (Committee for Economic Development: CED):
    This last is more compatible with recent developments in CSR thinking. While the pyramid and the IC model focus on the tension between business and society, the CON model highlights their interdependence.
    Regarding the impact of culture on CSR, see the article: "Cultural and leadership predictors of corporate social responsibility values of top management: a GLOBE study of 15 countries", in journal of international business studies, 2006; DOI:10.1057.

  • David Thomas Pegg added an answer in Electromagnetic Fields:
    Does spontaneous emission actually emit in a random direction, or is it measured in a random direction?

    When an excited state couples to the vacuum, it has an infinite number of directions of the quantized electromagnetic field to couple to. Does it evolve into a superposition of all those directions at the same time and only collapses once the photon is measured, or does it couple to only one? (Or, of course, is there no experimental way to tell?)

    David Thomas Pegg · Griffith University

    The wave function expands in all directions.  It collapses into one direction when it is detected.  There is no way to show this experimentally.

  • Arianit Reka added an answer in Silicate:
    Is there a table with all the types of calcium silicate hydrates (CSH)?

    Is there a table with all the types of calcium silicate hydrates (CSH)?

    Arianit Reka · State University of Tetovo

    It is greatly appreciated! Thanks a lot! 

  • Carlos Araújo Queiroz added an answer in Polyethylene Glycols:
    How can I detect polyethylene glycol concentration in a aqueous solution?

    Is it possible to quantify polyethylene glycol (PEG) using HPLC with RP18 column and UV detector?

    Carlos Araújo Queiroz · New University of Lisbon

    Those interested at this question, may possibly find useful to check a discussion on the analysis of triethylene glycol in water elsewhere at this forum:  https://www.researchgate.net/post/How_can_we_determine_Triethylene_glycol_in_water

    Moreover, for your possible interest, let me add that the analysis of ethylene glycol in sea water was also adressed: https://www.researchgate.net/post/Can_you_suggest_a_method_for_ethylene_glycol_determination_in_sea_water

  • Richard Seglenieks added an answer in Postoperative Care:
    What is the evidence regarding routine PPI use in post-cardiac surgical patients?

    Routine PPI use ('stress ulcer prophylaxis') is standard practice in some ICUs, however it has been found that as many as 40% of these patients continue taking the medication on hospital discharge, with the attendant risks of Clostridium difficile infection, community-acquired pneumonia and osteoporosis.

    Our ICU is currently developing guidelines on postoperative care for cardiac surgical patients, primarily to provide a basic framework for junior doctors regarding routine practice in the absence of any specific indications/contraindications.

    I am interested in hearing how people interpret the risk/benefit profile of giving, for example, 40mg IV pantoprazole daily, to post-cardiac surgical patients as routine practice. Should it be used universally, liberally, sparingly, or not at all for this purpose?

    Richard Seglenieks · Royal Adelaide Hospital

    Thank you for your responses. I find the comparisons between PPIs and H2RAs interesting - do some institutions routinely use these instead?

  • Richard Seglenieks added an answer in Perioperative Care:
    What scoring systems or risk stratification systems exist to assess perioperative morbidity and mortality?

    I realise this is a huge topic so any small contributions are appreciated.

    In particular I am curious as to what systems are actually used practically around the world - do you or your institution use any particular perioperative risk assessment tools?

    Richard Seglenieks · Royal Adelaide Hospital

    Thank you all for your contributions. I wonder how formal risk assessment methods compare to expert opinion of the anaesthetist/surgeon.

  • Omar Penarubia asked a question in Sorghum:
    What is the best way to dehull sorghum?

    Hello everyone!

    I am working on a project about sorghum flour/starch. I want to know what is the best way to dehull sorghum. Is tempering necessary? What is the best tempering condition (time and moisture content) to be used?

    Thank you very much!

  • Ljubomir Jacić added an answer in Unemployment:
    Is it a fact that increase of competion has forced us to become narrow minded?

    Because of over population, unemployment etc. the competition has increased a lot, which has changed our attitude and behaviour towards our colleagues. We have become narrow minded.

    Ljubomir Jacić · Technical College Požarevac

    Yes dear @Abhijit.We may say that your statement is correct. The increase of competition has forced us to become narrow minded! It is Globalization issue!

  • Jack M Gallup added an answer in Taqman:
    What is the acceptable difference in raw Ct values of technical replicates in a TaqMan Real time assay?

    If I am performing a Real Time PCR assay using TaqMan probes, what level of difference in raw Ct values is acceptable in technical replicates in the assay e.g. between three wells of the same plate that contain identical reactions? Is using a difference of 0.5-1 in Ct values good enough?

    Jack M Gallup · Iowa State University

    One should also note that the range of Cq values you are dealing with must include the effect that Poisson noise (Poisson distribution) and Monte Carlo sampling effect may have on technical replicates.  Cq values between 9 and 30 generally should not deviate more than 0.2-0.3 Cq units, while Cq values from 31 to 42 will be naturally expected to have more "noise" or variability associated with them (Cq values for technical replicates above 36 can exhibit 1.5 Cq differences and be totally understandable as stochastic realities in that Cq region; due to sampling probability and the Poisson distribution associated with it). In single-copy reactions, over many technical replicates, one weighs the number of negative reactions and positive reactions (nil-reaction analysis using a Poisson distribution formula) to identify the Cq that is emblematic of a single copy reaction for that target; in such cases some technical replicates will have no signal, while others will). E.g., in [droplet] digital PCR, copies/droplet = -ln(1-p) where p = the fraction of positive reactions among the total number technical replicates reactions run. A deviation of no more than 0.3 between technical replicates for Cq values between 9 and 31 may seem to be an acceptable general rule. But, 0.2 would be better; if possible.  Technical replicate variance can be minimized by preparing the entire technical replicates volume in a single tube, inclusive of all reaction mix components and sample, before administration to the plate wells as technical replicates. Some researchers set up the replicate reactions directly in the plate itself - inviting unnecessary user error which can adversely impact the ability of technical replicates to agree. 

  • Albert Pilkington added an answer in Lyophilization:
    Amyloid Road Block and really need HELP!!!?

        I need some help with my beta-amyloid protocol/ ThT assay. I’m getting it to work occasionally but the results are not reproducible to the point they need to be. When the assay works well the ThT curves are smooth and R.F.U.s are about 1000-1200. The incubation experiments monitored with AFM matched the assay data and everything was going well. Then I prepared a new batch and now the most I get out of my ThT curves is 160-500 R.F.U. for the control. AFM images of post ThT assay samples show fibril formation, but I’m stuck because batch to batch is not consistent in magnitude of beta-sheet content and kinetics are longer. I use 50µM ThT concentrations FYI. My current working protocol, that hasn't been reproducible, is to dissolve 1.0 mg of lyophilized Aβ40 in 1000µL of 10% NH4OH, incubate for 10 mins, and aliquot in 100µL amounts to ten tubes, and then snap freeze with liquid nitrogen followed by lyophilization of  the aliquots overnight @ -80C and 10-100µbar. The aliquots are then removed and stored in -80C until ready for use. Then an aliquot, allowed to reach RT >30mins, is dissolved in 10µL of 1% NH4OH (v/v) and diluted with ddH2O 106µL or instead it is dissolved with a 60mM NaOH solution @ pH 11.20. At this point it is introduced to a black/clr btm 96-well plate containing 20mM HEPES buffer pH 7.4 and 150mM NaCl in addition to treatments and a final peptide concentration of 20µM. The results, of the new batch, have shown low responses of controls and long kinetics time scales of aggregation. They also show an oscillatory type of behavior which I believe to be a signal-to-noise ratio issue. Which makes sense given the curves with oscillatory behavior and poor R.F.U.s have a signal-to-noise ratio of 3-5, while the better ThT assay gives a 19.37 ratio. I’m outright confused about my results and would appreciate any ideas, thoughts, or criticisms of why my results are not reproducible across batches. Ideas to troubleshot anything really?

    Albert Pilkington · West Virginia University

    I'm not gonna say what the treatments are because the data is unpublished but it is largely just an inhibitory effect. Also TEM is not useful for me I get more than enough resolution (~0.5nm in air) out of the AFM  I use to observe possible polymorphs, and TEM doesn't allow for in solution imaging which I want to use for this study. I edited my question some to make it more clear hopefully it is a little more understandable now.   

  • Ahmed A. El Tayyan added an answer in Graph Τheory:
    Which tools are used for drawing graphs in graph theory?

    I am writing a article in graph theory, here few graph are need to explain this concept.in ms word graph is not clear.so i don't know which tools is best to draw a graph.

    Ahmed A. El Tayyan · Al-Azhar University - Gaza

    If I understood your question, I say Origin software is quite good

  • Thao Tran added an answer in Immunofluorescence Techniques:
    How I count a number of macrophage on coverslip in culture after differentate from monocyte?

    I differentiated monocyte- derive macrophage on coverslip in 24 well plate with 1x10^6 cell/ml in total volume 1 ml per well but some cells died after seeding.

    I have washed non-adherent cells at 1 day after seeding. Then I've been culturing macrophage until day 7 and the confluent cells is about 70-80%.

    I've tried to collect macrophage by scraping and using EDTA and Trypsin but it make macrophage died and some cell were getting defragment. Cell number lost , so I'm trying to culture them on coverslip  

    My point is that I need to know the number of cell. How I estimate them? before I infect them with virus

    Can I count cells under microscope by taking photo and calculate the number from magnification or calculate by using a size of macrophage divided by area of well (24 well is 1.9 cm2)

    Does anyone know the size  of macrophage when it adhere on plate?

                                           Thank you very much

    Thao Tran · University of Queensland

    It is very hard to detach macrophage if you seed bone marrow cells on 24 well plates during differentiation. I usually differentiate them in 150 x 15 mm sterile petri dishes (Falcon) for 6 days. Basically, for each mouse femur/tibia, I put 20ml complete media and 1/5 fresh media is topped up each of 2 days. At day 6th, I remove media and wash once with warm sterile PBS to remove non-adherent and dead cells, then put 10mL of 1mM EDTA/PBS and incubate cells in 10min at 4oC. When collecting cells, I put additional 10 mL cold PBS to pipette cells out of the plate surface, then another 10mL PBS to rinse the remaining cells. After that I spin cells down, resuspending them with fresh media, counting the total number of cells and plating them on 24 well plate/coverslips for experiments on day 7th. The number of cells would not change much after differentiation. Choosing dish to differentiate macrophage is important, as different dish has different adherence properties that could not detach cells easily with Tripsin or EDTA. The 150x15 mm of Falcon company worked for me.

  • Md. Aminul Islam asked a question in Lipid Droplets:
    How to solubilize Lipid Droplets (LDs) specific proteins ( e.g., perilipin, PAT family proteins)?

    Researcher of Lipid Droplets (LDs) specific proteins.

  • Rolando Valero added an answer in Public Hospitals:
    Can u suggest me a good research that has been conducted on budgeting and budgetary control system in a hospital?

    Can u suggest me a good research that has been conducted on budgeting and budgetary control system in a single hospital? Preferably in a public hospital?

    I am doing organizational level research on budgeting and budgetary control system in one public hospital, so i need good priori researches that has been conducted on the issue. Thank you in advance for your help.

    Rolando Valero · Universidad Autónoma del Estado de México (UAEM)

    maybe....  the SAP system can help you to register every cost of the days in the year... and the historic information that SAP system will have... it will you help to do your budget for the future operation.  

    check this link please... i hope they can help you: