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  • Md. Siddiqur Rahman added an answer in Soil Carbon:
    Soil carbon sequestration, soil management practices and land use change?

    Their relationship

    Md. Siddiqur Rahman · University of Chittagong

    Might be the best example for a peat land that has been experiencing decrease in soil carbon due to land use change in both tropical and temperature region. However, with effective soil management activities like retention of wet condition, culture of fern type vegetation, paludiculture etc. may increase SC content.


  • Parimal Vijay Naik added an answer in MOFs:
    Which polymer for metal-organic framework (MOF) solution dispersion?

    Aiming on dispersing MOF particles in a suitable polymer matrix for thermal desorption and/or preconcentration, I am looking for a polymer that fulfills the following requirements:

    • soluble in organic solvents that can be removed by vacuum and elevated temperature (100-200 °C maximum). Neutral or almost neutral pH water would also be ok
    • thermal stability up to 200°C and low outgassing because this is a sensing application
    • macro- and/or mesoporsosity because the pore accessibility of the MOF should not be hampered too much
    • good dispersion for MOF particles with 10-60µm particle diameter and bearing mostly carboxylate groups on the surface.
    • Being compatible with the substrates to be finally coated on. This will be alumina, silicon or gold.

    The reason for this is to have a universal method in order to fast screen MOFs for this purpose and being able to characterize the - synthesized in bulk - MOF powder prior to this dispersion.

    Preliminary experiments with PMMA(996k) in THF - and afterwards added MOF powder - showed that the BET surface area was diminished but only by 20% as compared on a mass-percentage basis. Higher percentages of MOF ithin this system showed a linear increased BET surface area.

    I am sure there are some polymer-heads out there who may have some interesting suggestions. I am far away from being a polymer expert.

    Parimal Vijay Naik · KU Leuven


    You can try Polyimide (PI), Poly ether ether ketone (PEEK), polysulphone (PSF), these are glassy polymers with high Tg.

    Also, Rubbery polymer with low Tg you can try PDMS. It is also possible to coat a thin layer of PDMS with MOF on you desired substrate. PDMS is thermally stable up to 300 dgree C.

  • Ursula Ehrfeld added an answer in Perception:
    Are there any studies on problems in the perception of space?

    Many persons are not able to distinguish distances of objects and there may exist many different causes. 


    For me “information” about the outside world is represented by waves and oscillations.


    The waves and oscillations change the biological structure of the brain tissue in very many levels.

    1. Level: The biomolecular level

    There is the first level build up by the biomolecules. They encompass the amino acids, the nucleonic acids, the proteins, enzymes, the ion channels and ion pumps, and the so-called signaling molecules of the membranes. They encompass further all and any neurotransmitters, neuromodulators, and hormones.

    On this level, the characteristic waves and oscillations belong to the electromagnetic spectrum, primarily in the VIS and IR regimes. (See e.g. Andreas Barth, The infrared absorption of amino acids side chains.) Optogenetics make also use of the knowledge about this biomolecular level and its behavior.

    The most interesting feature of these waves and oscillations are not their frequencies but their wavelength, which are in the nm – mm range. William H. Calvin’s hexagonal patterns (see “The Cerebral Code”) are very well suited to wavelengths of the IR part of this spectrum! Wavelengths are best suited to measure and calibrate distances!

    Let me remind, that the retinal cells as well as the Place and Grid Cells are organized in hexagonal patterns. These hexagonal patterns make it possible to “catch” the phase information of the various electromagnetic waves and oscillations, which is important for my holographic hypothesis. Their characteristic dimensions correspond to about the wavelength of the biomolecules vibrational and rotational modes.

    The second level is the cellular level. Here we find, inter alia, the ion gradients which “effect” the local field potentials and the action potentials. A third level is build up by the white matter. Here we find the EEG oscillations.

    This post is an excerpt of another post of mine on another thread! Does it say anything to you? Do you see any analogies to your work?


  • How can I analyse the difference in the distribution of Likert items responses?


    I have several 6-point Likert items about opinions of the workplace. I also have different groups (e.g. Team1 and Team2, disjoint subjects) which I want to compare if their opinion differ significantly in some items. The teams have 57 and 61 observations, respectively.

    The main question I´m trying to answer: in which items is there a disagreement in the distribution between these two groups?

    My secondary question: is there any difference in the agreement/disagreement between these 2 groups in these items (by summing up the agree and disagree responses and in each item)?

    What kind of statistical methods should I use in both cases?


    Item 1

    (Strongly agree <---> Strongly disagree)

    Team1: 8-25-13-3-6-2 

    Team2: 5-11-18-13-4-10




    Bruno Penteado · MStech

    By the way, in some cases, the difference is very big: p-value of 5,2% in ChiSquare and 50,6% in MW.

    But, the opposite also occurs - p-value<5% for Mann-Whitney and >5% for ChiSquare, which makes more sense to me, since it is more difficult to differ in the order than in general.

  • Suman Raj asked a question in ns-3:
    Is it possible to use NS-3 to simulate the relays in the lte module?

    HI every ONE ! I'm learning to simulate LTE ( 4G) system in NS-2 .
    Have you ever do somethings with it or make any experiences .
    Would I have to know about your knowledges !
    Welcome for Any cooperation !

  • Sustainability and Corporate Social Responsibility (CSR). Are they similar or difference concepts?

    Hello everyone.

    Accordingly to European Commission (2002) and  ISO 26000:2010 International Standard, Guidance on social responsibility, Sustainable Development is a concept at global and intergovernmental level, while Social Responsibility is at organizational level and frames its contributions for sustainability.

    However, some academic authors have been presenting alternative definitions of CSR and Sustainability, offering a contrasting view between CSR and Sustainability: both focused on social and ecological good, but with CSR aiming to competitive advantages through marginal improvements, Bottom of Pyramid (BoP) as consumers and focus on current stakeholder needs while Sustainability is focused on durable competitive advantages though revolutionary changes, BoP as producers and focus on current, distant and future trends. 

    Although there is no consensus concerning the concept of CSR and Sustainability literature review allow us to conclude that most definitions take into consideration economic, social and environmental dimensions. 

    I would be very interested to know your position on this issue:

    - Let´s be pragmatic and improve the economic, environmental and social performance at all levels, regardless of definitions;

    - We should clear the definition issue beforehand and if this is the case where do you stand for?


    Best Regards

    Luis Fonseca 

    Jyoti Upadhyaya · Brock University

    CSR is a subset of sustainability. Sustainability requires one to follow a continuous process to improve on triple bottom line; and CSR is a way of going about it in corporate world. 

  • Is there anyone who can explain to me if the EtOH affects the binding COOH-NH2 or the EDC/sulfo-NHS coupling reaction or not?

    Dear all, I am trying to conjugate a short peptide having amine group with a fluoropho having COOH in the presence of EDC and sulfo-NHS. This fluoropho is hydrophobic so it must be mixed in EtOH. Is there anyone who can explain to me that if the EtOH affects the binding COOH-NH2 or the EDC/sulfo-NHS coupling reaction or not? and how? Thanks! Mai-Dung

    Selva Chemist (Bio) · GreyMatterResearch Foundation, India

    Dear Mai-Dung

    Ethanol never affect the binding of COOH-NH2 in your condition, in that no doubt. and same i agree with Avijit Pramanik answer,

    Good luck & Regards


  • Makhsud Tagirov added an answer in Embryos:
    Does anybody know the role of latebra and nucleus of Pandera in the birds embryo development?

    Latebra and nucleus of Pandera were described more than 200 years ago, but I could find no data about their role in embryo development. Does anybody have any information about the study of these structures, their functional role? 

    Makhsud Tagirov · National Academy of Sciences of Ukraine

    Thank you Salam. I knew these things very well, I've been working with the early birds' embryos for the long time. But Im wondering about the physiological function of these structures. Does anyone studied them? How the embryo use these structures?    

  • Mariana Puntel asked a question in Cobalt:
    Is 5mM DTT going to ruin my cobalt chromatography purification?

    Thermo recommends no DTT in cobalt chromatography (Hispure, # 89964) buffers. I wonder if 5mM DTT going to ruin my cobalt chromatography purification?Can anybody help me with this?

  • N.E. Powell added an answer in Amorphous Silicon:
    Why does the hydrogen content increase the bandgap of amorphous silicon?

    Hi everyone,

    I know from several papers that hydrogen increases the bandgap of a-Si:H. Now I have found the following bond dissociation energies in Lange's Hanbook of Chemistry: Si-Si: 327 kJ/mol and Si-H: 298.49 kJ/mol

    I don't understand how H can raise the bandgap of a-Si:H if the bond strength of Si-H bonds appears to be weaker than that of Si-Si bonds. Even if H just replaces weak silicon bonds the bandgap should not rise above the value of c-Si which it does. I have read that disorder rather decreases the bandgap than increasing it. So H and not disorder should be the reason why a-Si:H has a higher bandgap than c-Si. But how is this accomplished?

    N.E. Powell · Dow Corning Corporation

    I believe the mistake in is associating bond strength (or the required energy to remove electrons from stable shells in a molecule) with the required energy to cause a population of degenerate energy states to jump to the next available band, which is certainly less than the energy required to break the bonds.  The bonds of the crystal are not broken when electrons are promoted into the conduction band.  These electrons are not participating, per say, in the bonding and are thus excitable to a different energy state (where this energy state is the smearing of individual atomic or molecular energy levels into a set of degenerate states which form a continuum of energy states).

    It is the modification of the bulk band structure due to the overlap of individual atomic energy levels which causes band gaps to occur and be modified.  If you introduce different molecular structures you will perturbate this band.  This is a different aspect then just the molecular bond strength.

    While this does not answer your question, perhaps it helps set the stage and removes the confusion on band gap and bond energy.

  • What are the best tools for simulation and modelling?


    I wanted to know what are good tools for simulation and modelling and does it really need a tool? Can't we build our own software for out own system?

    I am new to this field only thing i know is there are two parts is such system 1) mathematical modelling 2) Graphical representation ( Its my perception need not be true).

    So can we mathematical modelling implement using any object oriented language and for graphical part we can use some tool to reduce efforts and time.

    Also suggest me some material that must be required to enter into field of simulation and modelling.

    Thank you.

  • Go J Yoshida added an answer in MCF10A Cells:
    Can anybody tell me about growing conditions for MCF10A cell line?

    We ordered MCF10A cell line from ATCC and seed the cells in suggested conditions except adding cholera toxin and pen/strep. We made three stocks in this conditions but then suddenly our cells started to die and we cant stop it.

    Our conditions are NOW : MEBM medium + MEGM kit + 100  ng/ml cholera toxin.

    We tried to remove cholera toxin but the results are same.

    Can anybody tell me where we are wrong?

    Thank you.

    Go J Yoshida · Tokyo Medical and Dental University

    I have also used MCF10A 3-D culture in Matrigel after reading the top-journal papers published from Professor Joan S. Brugge's lab. I attach the file about the detailed information about the culture medium. 

    In my opinion, the concetration of EGF ligand in the medium or the contamination with Mycoplasma might be responsible. 

  • Alexander Malm added an answer in Shear Stress:
    Working mode in a Rhéometer?

    What is the difference between working with a shear stress imposed or working with a shear rate imposed on a rheometer?i need a physical explacation pleaz.

    Alexander Malm · The University of Manchester

    The difference is what the rheometer keeps constant.

    In shear stress mode, the stress is is kept at a constant or ramped, but the speed at which the rheometer tool turns may vary.

    In shear rate, a constant or controlled shear rate is applied and the rheometer varies the amount of force on the rheometer tool in order to maintain this rate, meaning that the stress within the fluid can be measured.

    From personal experience, I have always used controlled shear rate.

  • Mohammad Rehan added an answer in Autoclave:
    I am interested in knowing effect of hydrothermal duration on average size of nanoparticle?

    and if the synthesized material remain in autoclave for one day is it result in rise of nanoparticles.

    Mohammad Rehan · King Abdulaziz University

    Dear Jie, Thanks very much for your endorsement.

  • Abbas Rahdar added an answer in Magnetic Materials:
    What is the origin of the formation of domain walls in magnetic materials?

    What is the origin of the formation of domain walls in magnetic materials?

    Abbas Rahdar · Zabol University

     Dear Kai ,

    please explain more about demagnetizing field and stray field.

  • Where can I find the questionnaire "The clinical learning environment inventory (CLEI)" developed by Dr. Dominic Chan?

    The clinical learning environment inventory (CLEI) developed by Dr. Dominic Chan has 42 questions. Where can I find this tool (questionnaire)?

    Lisa Winegardner · Norwich University

    Hello Jeanetta,

    No problem with the formatting.

    I have read the article you posted and still could not find the CLEI questionnaire. I do want to say thank you for taking the time to help me in my quest. Very sweet!


  • Inumidun Shotonwa added an answer in 2D NMR:
    Can anyone suggest on my 2D NMR problem?

    Amphipathic azobenzene molecular interact with β-CD through the host-guest interaction, however, there is no 2D correlation signals in NMR in water solution. What is the reason? Maybe the aggregation is formed by the amphipathic molecular itself, therefore little mount of the guest molecular interact with the CD. However, the induced Circular Dichroism signal can be detected.

    Inumidun Shotonwa · University of Lethbridge

    If you thinking of using a lower concerntration i think ROSEY will be the best 2D NMR yu are looking at because it is the best for small concentration

  • Lidia Mazur added an answer in Flow Cytometry:
    What is the minimal cell number per sample for cell cycle profiling?

    Does anyone of you know how many cells is needed to run a cell cycle distribution analysis using flow cytometry (PI staining)? Mouse ES cells have been treated with a certain agent and I expect the cell cycle distribution of the cells to be affected.

    Thanks in advance,


    Lidia Mazur · Jagiellonian University

    10 000 single cells gated or more

  • Sanjay Kumar Keshri added an answer in Origin (software):
    FWHM from origin?

    How I can write a command to get FWHM from a data file in Origin Software.

    Sanjay Kumar Keshri · Tyndall National Institute

    Dear Moritz

    I will follow these link

    Thanks for your reply and answer.

    Best regards


  • Might Teixobactin (discovered in 2015) be an answer for pan resistant MOST bacterial pathogens forever or for a short duration (couple of years)?

    Teixobactin was discovered using a new method of culturing bacteria in soil, which allowed researchers to grow a previously unculturable bacteria now named Eleftheria terrae, which produces the antibiotic. In the Nature study, teixobactin was shown to kill Staphylococcus aureus or Mycobacterium tuberculosis without the bacteria developing resistance.

    Hafid Soualhine · Institut National de Santé Publique du Québec (INSPQ)

    S. aureus and M. tuberculosis have shown no resistance upon culturing for few days on sublethal concentration of teixobactin. It does'nt mean that there will be no resistance. In M. tuberculosis, a slow growing bacteria, resistance development requires more time, and in some cases, successive contacts with the Drug. Even Teixobactin act on lipids, don't forget that there are other mechanisms of resistance by efflux pumps or others (ABC) tranposters.

  • Leon Black added an answer in Transformers:
    Why is the hemihydrate gypsum (CaSO4 0.5H2O) transformed from anhydrite (CaSO4) different from that transformed from dihydrate (CaSO4 2H2O)?

    At temperatures above 200 degree C, the dihydrate phase transforms to anhydrite. The anhydrite phase can absorb the moisture and transform to hemihydrate phase again. But this phase is much different in properties from the hemihydrate which results from calcination of dihydrate between 40-170 degree C. I was wondering what are the exact differences between these two? And why are they both called hemihydrate? 

    Leon Black · University of Leeds

    There are 2 polymorphs of calcium sulphate hemihydrate; alpha and beta. These polymorphs are known to behave differently with regards to their thermal analysis (see for example; http://nvlpubs.nist.gov/nistpubs/jres/76A/jresv76An1p41_A1b.pdf) However, their x-ray diffraction patterns are almost indistinguishable.

  • Debasish Pradhan asked a question in Austria:
    Anyone(Scientist/academician) from Austria who need to collaborate with me in a INDO-AUSTRIA (DST-FWF) Programe?Please send me your mail.

    resarch topic in characterization,imunoodulatory/ breast cancer/plant 

  • Hans Rediers added an answer in Rhizobium:
    Which is the best method to study interactions among two bacterial communities living in a habitat?

    Rhizobium and Pseudomonas are PGPRs which do interact in rhizosphere. We want to study them in the lab.

    Hans Rediers · KU Leuven

    It really depends on what you want to study. If you want to study differential gene expression for instance in the pseudomonas strain in response to the presence of Rhizobia, you could use a promoter trapping technique such as IVET or DFI. IVET is for instance used to study microbe-host interactions or microbe-microbe interactions. Alternatively, you could use RNAseq, but this is technically more demanding and more expensive.

    If you want to look for differences in utilization of C- or N-sources you could use omnilog.  

  • Jabbar Akhil added an answer in Big Data:
    Can you give me suggestion related to choose an research topic in computer science ?

    cloud computing

    big data 

    data mining

    i have an idea about these 

    if any one suggest the problem i can move to other domains also 

    Jabbar Akhil · Aurora's Engineering College

    cloud computing and network security,big data and cloud computing

  • Saeid Davazdahemami asked a question in LaTeX:
    How many medical latex do you know?

    can we  use some poison latex to produce proper medicine? in traditional methods we can see some of them in drugs.

  • How can we tackle nutritional problems in developing Counteries?

    Developing countries are now facing a double burden of nutritional problems i.e. under nutrition and over nutrition.What type of nutritional interventions will you suggest at the community level to deal with these problems along with the steps taken by various governments?

    Mohammad Monirul Hasan · University of Bonn

    Nutritional problem in the developing countries can't be solved only by the government interventions. Besides, Non-government Organizations (NGOs) have to play strong role in spreading knowledge and training. More emphasis is needed in the child and maternal mortality. If women can be treated properly during the pregnancy, the child will have proper development. So it starts from the family. Government should have strong monitoring on this maternal health and child health. Nutritional problem can be treated if we can educate the mother. Besides, fortified foods can also benefit children to get rid of malnutrition. 

  • Jack Silver added an answer in Food Preservation:
    What is the salt concentration of brine used for food preservation?

    There is any average salt concentration for making food brine?

    Does it depend of the food to preserve?

    Jack Silver · Teledyne ISCO, Inc

    This reference claims at least 20% to kill off bacteria: http://en.wikipedia.org/wiki/Salt-cured_meat

    Suggest you look up recipes and calculate the concentration. I've seen salt  added to whatever is being cured as salt crystals, so it is difficult to calculate the concentration (saturated?)

  • Lalit Kumar added an answer in Molecular Genetics:
    How to prepare RNase from powder form?
    I have been trying to prepare RNase (10mg/ml) by dissolving it in sodium acetate (5.2) and adjusting the pH with addition of tris 7.4, but every time I prepare it like this I end up with no good results. After running the gel i still get RNA contamination. Is there any other method of preparing RNase?
    Lalit Kumar · Gautam Buddha University

    can Nuclease free water  be used to make solution of RNase A from powder??

  • Pepijn de Vries added an answer in Hazard:
    What is the ceiling for Hazard to become a risk?

    Hazard is any factor or situation that has an adverse effect on man's health while risk is the probability of an unfavorable event occurring on someone. so does this implies that hazard is a dormant risk? what then is the threshold (ceiling) for hazard to be converted into risk?

    Pepijn de Vries · Wageningen University

    Dear Jia,

    It's all about definitions I guess... Hazard is an intrinsic property of an object, substance or situation. Hazard only becomes a risk when you are exposed to it (sharks can be very hazardous, but as long as you stay away from the water, you're not at risk). The risk level depends not only on the hazard, but also to the level of exposure to it and your (quantitative) definition of both hazard and risk. I think how you translate hazard to risk, once you're exposed, is therefore very case specific...