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  • Arnab Maity added an answer in Gold Nanorods:
    What happens to Silver during the formation of Goldnanorods by seed mediated method?

    We know that silver assists in the formation of gold nanorods and length of the rods is dependents on the concentration of AgNO3. But what happens to silver once the nanorods are formed??? Where does it go??? Is it still there?

    Arnab Maity · IIT Kharagpur

    Yes..this should be there... either top/bottom face of the nano-rod..

  • What is your preferred word-processor for writing papers or manuscripts? Word or LaTeX?

    I like to know how do you prepare your research papers for submission. Many of the journals give a choice - Word or LaTeX submission, but some journals accept papers only written in LaTeX. Some Universities also require PhD thesis to be submitted using LaTeX only. Which is easier? Which word processor do you prefer? Thanks!

    Palani Shanmugasundaram · Vels University

    Dear Sir,
    I am using only word. I don’t use Latex if there is really benefit in using La Tex for Pharmaceutical chemical formulas etc i will try to learn La Tex.
    Dr. Shanmugasundaram P •

  • Ruben Mercado added an answer in Toxoplasma:
    How can I remove free Ag from Toxoplasma tachyzoites?

    Is there a technique to remove free tachyzoite antigens from a suspension of Toxoplasma tachyzoites? I've tried washing in PBS, but the free antigen appears to be entering the pellet along with the tachyzoites. What is a better way to clean whole tachyzoites?

    Ruben Mercado · University of Chile

    if you are working with mice ascites fluid, as the ag are proteins, use centrifugation at low rpm, i mean 1000 or 1500 rpm, the parasite go to the bottom and upper liquid phase will have all proteins including ags...

  • What is the best way to remove dissolved oxygen from a reaction solution?

    My experiment requires totally oxygen free environment, how can this get? I used a reacted mixture solution in physilogical conditions.

  • Baris Demir added an answer in Storage:
    Best material for H2 storage

    For you what is the best material for H2 storage?, what is the reason?, advantages and disanvantages?

    Baris Demir · Istanbul Technical University

    I reckon you should check metal-organic frameworks (MOFs). MOFs have comparatively high gas separation and storage performance. The first step you should take is to make a literature review. Day by day new MOFs are being synthesized and benchmark data have been published. So, nobody could know the exact answer you want. Since the material selection is a complicated process, you should consider various parameters, such as operation conditions, thermal and mechanical stability, stability in the presence of water vapor, production cost etc. As a result, only you can know the answer after making a literature review.

  • Ankita Gupta added an answer in PEG Precipitation:
    M13 ssDNA preparation

    We obtained M13 ssDNA from NEB and transformed suitable host bacterial strain followed by phage preparation from the same. Phage was then used for purification of ssDNA by PEG precipitation and phenol extraction (detailed protocol was followed as given in Molecular Cloning by Sambrook and Russell) and was used as a substrate for enzyme assay. There was no activity found. However, when M13 ssDNA supplied by NEB was used for the assay, enzyme activity was detected. When both DNA samples (isolated in lab and supplied by NEB) were run on the gel, one isolated in lab was found to run slower than that from NEB (image attached). Is there something wrong with the way I am isolating ssDNA even though M13 phage used for this was prepared from ssDNA supplied by NEB?

    Ankita Gupta · Indian Institute of Technology Bombay

    I had used XL-1 Blue MRF' strain.

  • How can I cope with a degenerate multivariate normal distribution?

    I am studying a multivariate normal (MVN) model for inference on graphs. Due to the topology of the graph, the covariance matrix is singular by construction, resulting in a degenerate MVN. Due to this, I cannot use maximum likelihood estimation, since I cannot obtain the inverse of the covariance matrix. What is the best course of action in such a situation?

    Paul R. Yarnold · Optimal Data Analysis LLC

    Looking through my library there wasn't much, however the following offers some ideas which may be useful: Ronald A. Thisted, Elements of Statistical Computing: Numerical Computation, NY: Chapman & Hall, 1988. See section 3.5, Collinearity and conditioning, pp 92-105. A more thorough discussion of generalized inverses in linear statistical models appears as Chapter 3, in T.S. Arthanari and Yadolah Dodge, Mathematical Programming in Statistics, NY, Wiley, 1981. Tough problem!

  • Evi W Saragih asked a question in Statistics:
    Statistic analyses on vegetasi

    What is the statistic analyses that I can use with unbalace design study if I want to see the vegetation abundance relationship with envirimental parameters?

  • Amelia Shoemark added an answer in Ultramicrotomy:
    Where can I find an old ultramicrotome?
    Dear colleagues,
    I am looking for old, but working, ultramicrotomy equipment. If you have an old (fully manual, even) ultramicrotome (with a working optical system attached) and perhaps a knifemaker that you wish to get rid of, perhaps we can help each other. Thanks for your attention. Pedro (pmcosta@fct.unl.pt)
    Amelia Shoemark · Royal Brompton and Harefield NHS Foundation Trust

    We have one, although it is in London UK, could you arrange pick up?

  • Which is better personality traits or neuropsychology in predicting counter-productive/ cheating behavior?

    there are many literatures that used one or more personality traits to predict counter-productive behavior, on the other hand, I found some arguments about how  neuropsychology is better in predicting cheating.

    Fernando Barbosa · University of Porto

    The complete reference is: Dolan, M. & Park, I. (2002). The neuropsychology of antisocial personality disorder. Psychological Medicine 32(3), 417-427. DOI: 10.1017/S0033291702005378

  • Palani Shanmugasundaram added an answer in Author:
    What is the best way to present a Science Paper ?

    No problem exist when the subject is either a Theory, or Experimental results. The problem arises when the author(s) possess both, the Theory and Experimental Results, confirming each other. How to start the paper, with Experiments or with the Theory ?

    Palani Shanmugasundaram · Vels University

    Dear Sir,
    Any theory has to be proved experimentally in the same way we must start with the genesis of the theory followed by experiment discussion on it and with a conclusion, may be the suitable method which I am following in my research work.
    Dr. Shanmugasundaram P •

  • Jochen Wilhelm added an answer in ANOVA:
    Full factorial, ANOVA, Transformation

    I did a 2-level full factorial design with 3 factors in order to find the significance of each factor and their interactions on a response. After ANOVA on non-transformed response, I found no factors with significant p-value while 2 factors were obsereved with significant p-value when the same response was log- transformed. What can I say on significance of the factors? Are those significant or not?

    Jochen Wilhelm · Justus-Liebig-Universität Gießen

    First of all, if something is significant or not is your decision, and not (simply) the result of a test.

    Actually, to unbiasedly interpret the test results, you should know before analysing the data if and how the response should be transformed. However, you obviousely don't know it... so the test results are not interpretable in the way you'd like to.

    The typical way is to have a look at the residuals. Their distribution should not be too contradictory to the model assumptions (symmetry, variance homogeneity -> "normality"). From the look at the residuals you may be able to decide which model (the additive model with the untransformed response or the multiplicative model with the log-transformed response) is more appropriate (in light of the given data!).

    Since you then used the very same data to decide about the model and to analyze the model coefficients, the p-values must be interpreted with greater care. Selecting a coefficient with p<0.05, for instance, does not anymore guarantee to keep a type-I error rate of 5%. If this is your aim, then you will either need some justification for the model you chose that comes from outside of the data (and the results) or you need new data that you will then analyze based on the insights you have got from the present data.

  • Makmur Saini asked a question in MSE:
    What is the maximum hidden layers in the ANN to obtain the Mean Squared Error (MSE) as small as possible ?

    Example 2 or 3 or greater than 3

  • Could anybody help me to find best vector in order to get transient transfection into human fibroblast?

    I would like to perform transient transfection into human primary fibroblast with gata4 mef2c and tbx5. I do not want to perform viral transfection. 

    Could you give me some suggest? 

    Tuğçe Munise Şatır · Università degli Studi di Trieste

    Dear Vuong your vectorsuggestion is an absolutely what I want to have. Thank you so much. Dear Cedric I will evaluate your method reagarding to transfect cells and I will write you in any problem thank you so much.

  • For annual water quality assessment of lake or pond how far the temporal span or duration should be there between retrieval of samples ?

    Water sampling method.  

    Sainath Aher · Sangamner College, Sangamner

    Minimum 3, however seasons are changing while we can collect at daily month interval for identification of level of quality. 

  • Sainath Aher added an answer in DTM:
    Can anyone help me to find a DTM with a minimum resolution of 10x10m of Tuscany?

    I have to find some topographic attributes about a site affected by slope instability and I need a DTM with a good spatial resolution and moreover a good vertical accuracy.

    Sainath Aher · Sangamner College, Sangamner

    The LIDAR Dem is the best for your present work. 

  • Ljubomir Jacić added an answer in Rationalization:
    {Discovery, Invention, Rationalization} - the set of possible statuses of scientific results. What are the statuses are not included in this set?


    A new element in the periodic table - a scientific discovery
    The new model of known object - a scientific invention.
    An improved method of solving of known problem - a scientific rationalization.

    Ljubomir Jacić · Technical College Požarevac

    How do You treat a Patent dear @Vladimir? Patents exist at the contribution page of Researh Gate member if he has it!

  • Baris Demir added an answer in Viscosity:
    Where can I find the density and viscosity data of n-hexane or THF at -78 oC ?

    Density and viscosity of n-hexane or THF at -78 oC

    Baris Demir · Istanbul Technical University

    I recommend you to use the NIST Chemistry webbook where you can find various properties of compounds, from phase change data to thermochemistry data.

    The web address is 


  • Samuel Chew added an answer in Geriatric Medicine:
    Is Geriatric Medicine gaining importance in the present scenario of increasing ageing population and change in the mindset of society on elderly?

    Geriatric medicine is becoming popular nowadays due to the increase in the patient who need attention/hospice care.

    Samuel Chew · Changi General Hospital

    Dear Sandra,

    I empathise with you as regards the difficulties that you face in actracting young clinical trainees. Similar picture is emerging with medical trainees. In truth and fairness, it is a difficult field to work in, having to deal with many end of life issues and the impact of chronic illnesses on frail elderly people, many living in difficult financial and social circumstances. Furthermore, the financial rewards and recognition for work in this very important area is often lacking.

    Still I find it inspiring that there are people like yourself who can see the need for well trained clinical staff to look after the older patients. Many of the Geriatric nurses and assistants whom I work with both in UK and Singapore find great satisfaction in their work, and this remains the dominant factor for choosing and remaining in Geriatric nursing. I do my best to help by recognising their efforts, supporting them at work and encouraging all to further develop their skills and knowledge.

    Last but not least, I have observed that a clinical focus on "independent living", "functional optimisation" rather than supporting dependency in isolation, and timely switching to palliative care for appropriate critically ill patients helps to promote optimism and reduce emotional "trauma" for the nursing and multi-disciplinary staff, particularly those whom have just joined us.

    I am sure there must be some research in this area but apologise for not having one to share at present..

    I have to confess that I am a Geriatrician because of my love for Medicine, solving complex problems and of course, a love for the very elderly amongst us. Nothing more.

    Best regards to you as you carry on forth to promote this vital area of nursing!

  • Mayur Narkhede asked a question in Data Structures:
    What is the best proven data structure to store and access the information about large number of nodes, edges and clusters?

    I am working on the layouting algorithm, for this i need a data structure which should able to store, access information about nodes, edges and clusters very efficiently
    This structure should able to handle atleast data about 10000 entities. Please help me if nay one has worked on such problem?

  • Ali Fertas asked a question in Malaysia:
    Private Healthcare in Malaysia. What is the future of private healthcare in Malaysia?

    Discuss the background of Malaysian private healthcare and its evolvement over the years. Analyze the factors that affect the demand and supply of private healthcare in Malaysia.

  • What are the typical causes of spontaneous parametric down-converted photon-pair quantum state impurity when performing polarisation tomography?

    We are performing polarisation quantum state tomography of photon pairs generated through spontaneous parametric down-conversion by following the approach described in this paper: https://www.researchgate.net/publication/235531853_Measurement_of_qubits

    Although we expect the quantum state to be pure, we are getting fairly low purity values defined as purity=trace(rho^2)), where rho is the density matrix. What are the typical causes of spontaneous parametric down-converted photon-pair quantum state impurity when performing polarisation tomography? How can we check whether something is wrong with the photon pair generation or with our implementation of the tomography procedure?

    Alexander S. Solntsev · Australian National University

    Thanks a lot for the list Gabriel!

    I hope we'll solve it soon.

    Best regards,


  • Vishnu Rajendrakumar asked a question in Orbit:
    Is there any acceleration is needed for an electron to jump from one orbital to another orbital?

    suppose a suitable energy is given to an electron in a shell, it will absorb energy and it jumps to the next orbit. since it was highly unstable there it will emit the energy as  em radiation and comes to its original shell. for this to and fro jumping from one orbit to another, is the electron need any kind of acceleration?

  • Morteza Salehpour added an answer in Dairy:
    Does anyone know how much the price of per unit milk production? how can calcutet this by simple equation?

    i working at the cuttle farm and use same initial  requirement for prudence.I want to calculate ultimate price of production.I need to best an simple formula of pric product.   

    Morteza Salehpour · University of Zanjan

    Hi Mehran

    As you know  dairy farms can vary so much from one farm to another that one, therefore equation included all variables would be difficult to build .In Agriculture economic , you have to determine variable costs ,fixed costs, opportunity Costs.also for calculating  milk production breakeven level , you can use Chand 2002 formula.

    Chand, K., Singh, K. and Singh, R.V. 2002. Economic analysis of commercial dairy
    herds in arid region of Rajasthan, Indian journal of agricultural economic.

  • Could you send me the supplementary information parts of this journals?
    I have some dilemma in my mind about the calculations of this journals. Perhaps if I see detailed information I can solve the dilemma. Unfortunately, I can't access the supplementary information. Can you send it to me?
    Ludovic Duponchel · Université des Sciences et Technologies de Lille 1

    Dear Tugba,

    Please find enclosed two files of the supplementatry material.



  • Can I calculate the size of thermodynamic segment (Kuhn length) based on the chemical formula of the substance without a computer simulation?

    Kuhn length calculation

    E. S. Zhavoronok · Russian Academy of Sciences

    Carlos David Zapata, Douglas R Tree, thank you very much!

    I assumed that segment size/ Kuhn length depends on the flexibility of the monomer unit chain, which is defined among other things by its chemical structure (bond nature and length). However, It seems that I can't have a Kuhn lengths without a computer simulation:-(

    I want to analyse some of the polymer chains of infinite length in the absence of solvent and at the same temperature to characterize their flexibility (flexibility of chains) and to correlate witn some properties of materials.

  • Sainath Aher asked a question in Topography:
    Is there any high resolution data of surface topography, such has DEM ? How can download the same at free of coast ?

    Objective: precise modelling of river bed. 

  • Tim Heenan added an answer in Literature Search:
    Can someone suggest any references for 'Methods and Efficiency of Adult Education in the French Republic'?
    Study conducted at Warwick University. Looking for documents in the French Language
    Tim Heenan · The University of Warwick

    Hi Dirk,

                 Many thanks for your answer, I will follow that reference up. I am also looking at  some French and French Canadian adult education websites as both countries follow the same pattern. Are you involved with French education, if you don't mind me asking?


  • Surender P. Gaur asked a question in Water:
    Water insoluble triglycine sulfate !

    is it possible to make water resist triglycinesulfate?

  • Georgianne W. Moore added an answer in Sap Flow:
    Can anyone tell me how we measure the water mining rate of tree crop ? will xylem sap flow system alone do?

    I would like to know whether just a simple and single measurement system like sap flow meter with TDP or  other probes is  enough for monitoring the water consumption rate of tree crops like apple, rubber, mango etc.

    Georgianne W. Moore · Texas A&M University

    Sap flow velocity is easier to obtain than whole plant water use unless you measure flows across the entire active xylem. Before choosing this method, find out how others deal with up scaling (I have some papers on that).  Apple and mango will be much easier than rubber. Here is one publication that might help.