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  • Bogdan Pawłowski added an answer in Steel:
    How exactly B increases hardenability of hypo-eutectoid steels and not for hyper-eutectoid steels ?

    How exactly B increases hardenability of hypo-eutectoid steels and not for hyper-eutectoid steels ?

    Bogdan Pawłowski · AGH University of Science and Technology in Kraków

    Quite good explanation you can find here: 

    Screenshot attached :)

  • What's the interpretation of single photon interference in a double slit experiment?

    I want to know what are the reasons of this interference.

    How does quantum mechanics look for this interference? Does the photon interfere with itself or are the waves accompanied with it interfering with each other?

    What's the relation of wave particle duality with this experiment?

    What are the most acceptable interpretations of this experiment?

    Johan Frans Prins · Sage Wise 66 (Pty) Ltd

    Dear Leyvraz,

    You are wrong: A solution of Maxwell's wave equations without specifying the source, is NOT physically possible. A solution without specifying the origin of the wave is PURELY a mathematical solution which is waiting for gauges to be applied for it to model physics. It is easy to solve Maxwell's equations for a SINGLE frequency source, and if the source has ONLY emitted this SINGLE frequency wave for a time t, this wave cannot be longer than ct along the directions it has been emitted

    If it is a spherical wave it fits within a volume with radius ct and fills thus a limited volume. A SINGLE light-source cannot emit an "eternal-wave" . It can only emit a wave filling a volume while the wave has a single frequency. It does not need more than a SINGLE frequency to occupy such a volume:  As any radio-engineer who works with Maxwell's equations can attest.

    Only stupid mathematical physicists believe that a SINGLE frequency demands an infinite volume. Such a wave cannot exist at all. No differential equation is solved until the boundary conditions which determine the relevant gauges have been found. There is no such thing as  "gauge-invariant" physics I wish somebody would force mathematical physicists to study engineering!!. Without this background a "mathematical physicist" is like  tomcat without balls.

  • Xianqing Mao asked a question in Puzzle:
    Does anyone can share me your experience on concentration-dependent effect of TGFbeta1 treatment on MCF7 cell line?

    Hi everyone,

    I would like to induce EMT in MCF7 cell line by TGFbeta1. From the literature, TGFbeta1 alone seems to induce a partial EMT even for one-week treatment. And this effect is concentration-dependent. What puzzle me most is that TGFbeta1 inhibits the mRNA expression of my gene of interest but up-regulates the expression level of protein. If this is really the case and if this is possible, what can be the mechanism?

    Thanks a lot


  • Asolina Braun added an answer in Bone Marrow:
    Does anyone have experience in generating murine Plasmacytoid Dendritic Cells (pDC) from FLT3 Ligand-supplemented bone marrow cultures?

    I have been trying to generate murine pDC by supplementing bone marrow cultures with FLT3 Ligand. I seed 1 x 10^6 cells/ml in 6-well plates, using 200ng/ml of FLT3-L.

    When harvesting the cells (after 7-9 days of culture), I typically recover only 10% of the cells I originally seeded. Whilst bone marrow preparation and subsequent culture appears to be OK, I seem to be falling at the last hurdle when it comes to harvesting the cells.

    I have checked the literature and can't figure out what I am doing wrong. If anyone has any experience in performing these cultures, I would be very grateful for any advice/wisdom you can provide.

    Thanks in advance!

  • Dipanjan Kumar Dey added an answer in Likert Scale:
    What tests of association should I run in SPSS?

    I have 135 student responses to a likert scale survey about students' perceived engagement and creativity in class. 

    I'm trying to determine what tests of association to run in SPSS.

    Guidance greatly appreciated! 

    Dipanjan Kumar Dey · IBS India

    Clara please follow what Nicholas has advised. Absolutely on the money. If possible include more constructs and /or variables to improve depth of analysis, consequently improving contribution to fellow researchers.

  • Richard Chadd added an answer in Chironomidae:
    What is this Macroinvertebrate family? I would appreciate if any one could could help?

    Please see the animal from the attached file. Thank you.

    Richard Chadd · Environment Agency UK

    I would be reluctant to go beyond subfamily level, but I would go with Chironomidae:Orthocladiinae.

  • Giovana Mazzotti added an answer in Animal Behavior:
    Has anyone used the Canine Behavioral Assessment and Research Questionnaire (C-BARQ)?

    Would anyone be willing to share either their experience in using the C-BARQ, or perhaps even be willing to share the data they collected? I'm currently working on my master's thesis regarding the behavior of working dogs and I'd love to get a hold of at least some of the data already gathered from the C-BARQ to compare the rates of behaviors among different groups of dogs.

    Giovana Mazzotti · Faculdades Integradas da União Educacional do Planalto Central

    I know a person who can help you.

    His name is Vanner Boere, and he's a great ethologist!


  • Vaishali Sharma added an answer in DNA Isolation:
    Does anyone know about robotic DNA isolation from potato tissue either from leaf or tubers?

    I certainly have more than 400 plants and need to isolate DNA using robotic method. I have tried as one sample but its yield is not expected level, but I want to use it. If anyone has idea how much tissue should I take it from leaf or tuber tissue, please let me know and this would be great for my ongoing research. Any idea about this would be also beneficial for me.

    Vaishali Sharma · Consultative Group on International Agricultural Research

    You can use genogrinder for that it is very efficient and time saver. We normally use it in our lab. We can do 500 samples extraction in the single day itself.


  • How can I sort a recombinant protein to the membrane of mammalian cell lines?

    Hi Dear all
    I wanted to express a recombinant protein the cell membrane of mammalian cells. Now the case in point is, What kind of sorting signal should I use? my second question, Is glycosylation process necessary for sorting proteins form ER to plasma membrane or not?

  • Mehdi Keblouti added an answer in Climate Change:
    Does anyone have a climate change corpus that I can use?

    Dear respected scientists and colleagues,

    I am looking for a climate change corpus to do text analysis on it. If you have one or you know a journal that I can download their abstracts I would be very much obliged.



    Mehdi Keblouti · Badji Mokhtar - Annaba University

    Hi ahmed , You will find in attached file articles in climate change,

    If you have ? i can sent other series of articles

    I could not send it by mails, I do not know why ?

    good luk


  • Syed Anjum asked a question in Journal Impact Factor:
    Did all impact factors journals include in Thomas router master list 2014?

    I am searching  X category journal list which is being upgraded to W category.

  • How can I mathematically model the behaviour of the humans?

    Any suggestion/resources are appreciated.

    Mahmoud Omid · University of Tehran

    No. they are just approximation but still practical in medicine and other places. Some models of human behavior in the social sciences assume that humans can be reasonably approximated or described as "rational" entities. As I said before,  mathematics is not a goal or end in itself, rather a tool in such studies, so long as it can contribute to the effort. The purpose is not simply to create “mathematical models” for their own sake. What they are good for actually? Mathematical models can be used to further our understanding of the factors that motivate individuals in , for example, making medical decisions, taking into account the interplay among biological systems, individual decision-making and social and cultural influences

  • Starting an English Language Development unit?

    I'm planning to start an English language development unit in my work place. It is a scientific research center in which the staff are of varieties of scientific specializations.

    The main purpose behind the unit is to help enhancing their linguistic capabilities as far as the academic use (like in research writing, public speaking, etc).

    I'd appreciate your suggestions for better planning.

    There are plenty of free resources at different platforms like European Shared Treasure,  eTwinning, British Council...

  • Alan Bullock added an answer in Hypertrophy:
    Could this type of intervention lend itself to greater improvement in VO2max and LT?

    As the findings of this study also found hypertrophy of the type I fibers - do you think BFRRE could be used to substantially increase the ratio of type I to type II fibers and when accompanied with endurance training substantially increase the oxidative capacity of the muscle fibers? I.E. Larger type I fibers may increase mitochondrial content when endurance training is employed also. Also out of interest what rep range was used for the study?

    Alan Bullock · Sheffield Teaching Hospitals NHS Foundation Trust + Sheffield Hallam University

    Thanks for your input on this. What I was trying to say was if you increase your proportion of type I fibres by volume (not by proportion) then with the correct aerobic training as well - I thought it may be possible for increased oxidative capacity of the slow twitch fibres. With increased size of non oxidative fibres from standard hypertrophy training this could lead to a drop in oxidative capacity (oxygen has greater distances to diffuse in larger muscle fibres to reach mitochondria). It would be interesting to see if any difference existed between two groups who did HIT with one employing BFRRE as well?

  • Sundarapandian Vaidyanathan asked a question in Space:
    Do we live in a 4-D or 5-D space?

    There are different ways of viewing the world we live in!

    One common way is to interpret it as a 4-dimensional space - three spatial dimensions (x, y, z) and the fourth dimension is time (t). Thus, we can denote each coordinate as (x, y, z, t) with time-t evolving. Whereas it is easy to visualize x, y and z coordinates moving, it is not so easy to visualize the time-t moving.. We can neither move forward nor backward in time. Science-fiction stories and movies like "Back to the future" have played with the idea of 4-D space facilitating movement backward and forward in time (hypothetically with a vehicle).

    In physics, the fifth dimension is a hypothetical extra dimension beyond the usual three spatial dimensions and one time dimension of Relativity. The Kaluza–Klein theory used the fifth dimension to unify gravity with the electromagnetic force (see Wikipedia link below for 5-D space).

    A book by Paul S. Wesson (2006) titled - Five-Dimensional Physics: Classical and Quantum Consequences of Kaluza-Klein Cosmology (World Scientific, Singapore) - describes in detail about the hypothetical five dimension.

    In popular culture, the fifth dimension is often used as a metaphor for unexplored and unknown aspects of the universe.

    I have given ample details about the query and I welcome your views - do we live in a 4-D or a 5-D space?

    Thank you!

  • Can I re-use the secondary antibody in western blot analysis?

    While I am doing western blot analysis several times, within one week, I am usually using the same diluted secondary antibody solution in TBST 1X buffer for 2 times. Practically, it works with me. However, how many times and for how long can I re-use the diluted secondary antibody?

    Manoj Kumar Singh · Calcutta School of Tropical Medicine

    Yes, you could re-use both primary and secondary antibodies. It would depend on the dilution of antibody and their dilution buffer that you are using. Generally BSA dilution buffer are the best method to achieve your goal.

  • Abdur rahim Khan added an answer in Biotechnology:
    Which type of the sport exercises have the most positive effect on creativity of our brain in the research?

    As researchers (and no matter in which field: optics, engineering, physics, mathematics, biology, medicine, biotechnology and etc.), many of us are most of the time dealing with research work, and often forget that there is also a life outside the university. But our efficiency decreases with the time and good ideas are not born. 

    If we are willing to allocate an hour a day or an hour in a few days for sport, which sport will improve the creativity of our brain in the research?

    All kind of exercise which involve physical and mental activity which most of games have and every activity is good irrespective of type of activity. As scientific approach, I can say that certain activity can be optimum for certain type of personalities, So one can identify that activity which give him/her much fruitful results. As well one kind of activity cannot be enough good for every one. But on personal experience, any physical game helped me much......:)

  • Hossein Shaki asked a question in Polymer Structure:
    What is the meaning the size of peak in FTIR spectra?

    I have syntesized a polymer with dextran and in FTIR spectra there are many peak which related to different molecular bond in polymer structure. An specific peak (such as a peak in 2500 nm-1) in two FTIR test has different peak intensity. I would like to know is there any differences between these two peak?

  • Is it possible to create self-learning intellectual system?

    Creation of such a system is one of the main goals of artificial intelligence.

    Vasily Osipov · Russian Academy of Sciences

    To create a full-fledged self-learning intelligent machines need to significantly develop their theory and implementation technology.

  • E. Cisternas added an answer in Quantum Mechanics:
    What are some of the most important applications of quantum tunneling effect?

    Thanks in advance.

    E. Cisternas · Universidad de La Frontera

    Scanning tunneling microscopy (STM), an essentual tool to understand the behaivoir of nature at nanoscale.

  • Miriam Conzen added an answer in Photovoltaics:
    Can you give me your opinion on which lags to include in my AR?

    Hey everyone,

    I want to create an AR process to forecast electricity generation by photovoltaic plants. I have the data of three sample photovoltaic plants to develop identify the best number of AR-lags. Later I want to use that model to predict the electricity generation of over 300 photovoltaic plants.

    I started with determining the order of my AR process by calculating AIC and BIC for each sample plant. Then I eliminated insignificant lags for each sample plant.

    Now I am left with different significant lags for each of my three sample photovoltaic plants:

    Plant 1: Significant Lags are 1, 2, 3, 4, 23

    Plant 2: Significant Lags are 1, 2, 4, 23

    Plant 3: Significant Lags are 1, 2, 3, 4, 20, 23

    I've got two options now: Either I can include ALL of these lags in my final model, or I can only include lags that are significant for ALL of my three sample plants.

    I would be very grateful to get your opinion on this matter.


    Miriam Conzen · University of Duisburg-Essen

    Thank you everyone for your answers!

  • Kamal Eddin Bani-Hani added an answer in Happiness:
    As a Project Manager what steps will you take to win back the trust of stakeholders with the limited resources available to see the project deadline?

    In line, a stakeholder is usually an investor in your company whose actions influence the result of your business decisions. Stakeholders don’t have to be equity shareholders. They can also be your employees, who receive a stake in your company’s success and incentive for your products to follow. They can be business partners, who rely on your success to keep the supply chain moving. Every commercial enterprise needs a different approach to stakeholders. The roles of stakeholders differ between businesses, depending on the patterns and duties laid out at the foundation of your companionship or as your business evolved over the long time.

    A project is running behind schedule and its stakeholders are not happy with the project scope and demands a change. As a Project Manager what steps will you take to win back the trust of stakeholders with the limited resources available to see the project deadline?

    Kamal Eddin Bani-Hani · Hashemite University

    Be honest, transparent and frank. Tell them that you are serious and working hard

  • Corinna Ernst asked a question in GATK:
    Is Indel Realignment recommended previous to Structural Variant Calling?

    Is there any experience how GATK's IndelRealignment influences the results of subsequent Structural Variant Calling, e.g. with DELLY?
    Does Indel Realignment improve the predictions or should be skipped?
    I want to process HiSeq2000 paired-end reads.
    Thanks a lot!

  • Raffaele Strippoli added an answer in Spleen:
    Can anyone suggest a suitable condition to stimulate p38?

    I want to know suitable condition to stimulate p38 (accept PMA and LPS) for optimizing antibody. i am working with mouse, i use spleen and bone marrow.

    Raffaele Strippoli · Sapienza University of Rome

    Sorbitol, anysomicin, sodium arsenite 50 micromolar

  • What is the best indicator of product profitability?

    The literature on the subject is very poor. As a result, many companies use inappropriate methods, which are based on fixed cost sharing.

  • Does someone have work that has been carried out using collaborative filtering in e-learning ?

    I look for work that has been carried out using collaborative filtering in e-learning

    Martina Holenko Dlab · University of Rijeka

    I suggest that you read about ELARS recommender system:



    Kind regards,


  • Hello, "Is there any ratified questionnaire in Spanish that measures the healthcare professionals´cultural competence?

    I would like to do research on cultural competence in nursing in Spain. Thank you!!

  • Lakshmana Reddy added an answer in SSR:
    Can you suggest selection criteria for the selection of SSR markers from the list?

    Please suggest the selection criteria for the selection of SSR markers designed from the NGS data (Transcripts).

    Which type of markers will be useful to study genetic diversity between different genotypes? Di nucleotide? Trinucleotide? Tetranucleotide SSR markers?

    And how do you find the mono allelic primers from the list of primer designed?

    Lakshmana Reddy · Indian Institute of Horticultural Research

    Select SSRs uniformly from each chromosome if linkage map is available for general studies 

    SSRs with high polymorphic information content values always better  

    if your are looking at specific loci, select shortest distance  linked SSR/ SSRs 

  • Peter Schluessel added an answer in Surface Tension:
    What is the relation between the surface tension and acidity/basicity?

    Surface tension of pure water is 72 mN/m. But it varies with the addition of acids and bases. why?

    Peter Schluessel · European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT)

    There are different methods to build a tensiometer. The pendant drop method requires goniometry. A more accurate method employs force measurements, the  Du Noüy-Padday method (Padday, J. F., Pitt, A. R., Pashley, R. M., "Menisci at a free liquid surface: surface tension from the maximum pull on a rod",J. Chem. Soc., Faraday Trans. I, 71(10), 1919–1931, 1974). The claimed accuracy is 0.1 mN/m.

  • Reiner Rockel asked a question in Desiccation:
    Are there atmospheric water-vapour harvesting methods known, where a desiccant-fibre (natural or synthetic) absorbs the moisture?

    Most atmospheric water-vapour harvesting methods, which I found so far, are based on the principle of dew formation. Triggering adsorption by moving air passed an hydrophobic / hydrophilic object (e.g. foil) which is cooled below dew point.

    Are there any projects known/research done where a desiccant-fibre (e.g. Wool, Cotton, Polymers) absorbs atmospheric water-vapour in hydroxyl groups and/or amorphous areas when being exposed to air?
    The harvesting happens in a second step when increased energy ‘breaks’ the water away from the desiccant. So far, I know only of one company (www.aquasciences.com) which is using this principle, charging a salt.