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  • Phani kashyap S added an answer in Fungal Endophytes:
    How do I reduce bacterial and fungal endophytic contamination in bamboo tissue culture?

    auxillary node culture

    i used 3 mg/l of cefataxime sodium salt

    can i use antifungal agents in media? if so what?

    Phani kashyap S

    To reduce fungal contamination use Bavastin. i.e. washy your seed or plants with Bavistin.

    To reduce bacterial contamination wash ut seed or plant with 2 x antibiotic solution.

    If the seed coat is strange use fumigation method to sterilize your seed in desiccator ( ml Sodium Hypo-chloride and  3ml con HCl in desiccator for over night.

  • Anoop Kumar Srivastava added an answer in Soil Fertility:
    How can we proceed for decision on soil resource-based cropping sequence?

    Development of soil resource inventory of a given area , is considered highly imperative to take decisions on the options about the suitability of different crops in a farming system mode. At the same time, the information on edaphological requirements of different crops , is equally paramount , so that both are super-imposed in such a way, to delineate soil-crop analogues. This will pave the way for better land utilization efficiency. My further querries in this regard are as follows:

    * How should we develop a soil resource inventory ?. Shall we go for master soil pfofile stdies  or follow the grid- based soil sampling  coupled soil profiles to be later used for developing soil fertility variograms?. 

    * How shall we identify the soil fertility constraints of multiple nature from such soil resource inventory?.

    * What methodology , shall we adopt to identify   optimum soil requirement for different crops ?.

    * How should we identify the cropping sequence based on such soil resource inventory?.

    * Whether cropping sequence and land utilization efficiency are inter-related ?.If so , in what way?.

    I request my esteemed colleagues to share their experiences on these issues. Regards

    Anoop Kumar Srivastava

    Let  me share  with my learned colleagues on this important  point raised earlier . We still have a long way to go before we have precision -based assessment of site evaluation and crop-based assessment of nutrient constraints. We in India ,  do not think ,  we have the soil fertility criteria with respect to horticultural crops including tuber , plantation, spices and vegetable crops, off course with certain exceptions for the crops like potato , banana, citrus , mango , grapes, rubber , tea, coffee etc... We do have digitized soil fertility maps for many districts ( some 160  odd districts or..) , which is being now used as a part of the second phase by superimposing the specific  crop boundary  to have a first hand information  about the nutrient constraint assessment . This will gave the generalized information , not more than that . In this regard , very shortly geo-portals are in the pipeline to be flagged off very soon .

  • Vivek Negi added an answer in Source Apportionment:
    I have 14 data sets for 5 location in an area in terms of elemental profiles, then what possible source apportionment method can be used effectively?

    What model to be used given 14 data sets are available for receptor sites? (given source profiles are available and major sources are known) Will CMB work with only 14 data sets of only elemental concentration??

    Any other alternative to find re-suspended dust and combustion sources impact quantitatively??

    Vivek Negi

    Sorry for the confusion here but i have total 15 samples or 3*5 datasets you can say.

    So only 15 elemental profiles i have in total in receptor area. I dont think PCA or PMF could be an option here as they need atleast 100 datasets. So the problem im facing is to find the impact  of resuspended dust with such minimal samples.

  • Ramiah Barani asked a question in PET/CT:
    I have the series of PET and CT images from PET/CT scan. Can anyone suggest me some books or papers for interpreting those images?

    I am working in image fusion. I got those images from CancerImaging Archieve. Also I need some help to know how to correlate the corresponding images from both series and to convert them to same size.

  • Beckline Mukete added an answer in Biodiversity and Conservation:
    How do I measure alpha diversity when measuring plant diversity in household gardens

    We are working a rearch project in a village located next to a National Park in Guatemala, and we are interested in finding out the contributions to in situ biodiversity conservation that takes place in household gardens.  Based on some literature review, alpha diversity can be measured at the household level (as a conservation unit that has a particular management regime), nevertheless we are interested in receving feedback and comments about it. 

    Beckline Mukete

    Hi Carlos,

    This will depend on the conceptual framework of your research or the questions you intend answering. I would advice you to go by Whittaker (1972) and use differential species assessment (number of species) and abundance of each assessed species i.e  proportion in which each of the assessed species is represented within your reference point. Shannon's diversity index is useful for a more complex assessment sites which your garden is not.

    Alternatively,you can also take a look at our paper where,we assessed biodiversity in an urban green area of Copenhagen, Denmark.     https://www.researchgate.net/publication/269409218_Assessing_the_Effectiveness_of_Urban_Nature_Reserves_on_Biodiversity_Conservation

    You could also take a look at the following publications: Podani, J. and Schmera, D. 2011. A new conceptual and methodological framework for exploring and explaining pattern in presence-absence data. – Oikos 120: 1625–1638

    -Lawton, H., Bignell, E., Bolton, B., Bloemers, F., Eggleton, P., Hammond, P (1998). Biodiversity inventories, indicator taxa and effects of habitat modification in tropical forest. Nature 391: 72-75.

    -Coetzee, B; Kevin, J and Steven, L (2014). Local Scale Comparisons of Biodiversity as a Test for Global Protected Area Ecological Performance: A Meta-Analysis. PLoS ONE, 2014; 9 (8): e105824.


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Around the globe, environmental policies have always favouredurban green spaces for recreation and tourism. But, these green spaces also serve as habitats for plant and animal species, facilitate soil water retention and carbon sequestration. One of such green spaces, is the Byoasen located in the Nørrebro suburb of Copenhagen, Denmark. A biodiversity survey was conducted aimed at assessing species composition, richness and biological heterogeneity. The species richness (flora and fauna) data were collected and weighted against natural factors e.g. arbor cover and anthropogenic factors e.g. human activity. The results suggested that biodiversity richness increased with increased arbor cover and within areas with little human access.
      12/2014; 2(2):130-134. DOI:10.12691/aees-2-6-1
  • Arunima Haldar added an answer in Risk Management:
    Is it feasible to depend on secondary data only for a study titled Risk Management and firm’s performance?

    I would like to prepare a study plan on Risk Management and firm’s performance. Could you lease suggest me some articles on the area. Besides, I want to depend my study on secondary data only, can you please comment on my plan?

    Arunima Haldar

    This can be done and depends on how you define risk or what exactly are you capturing by risk.

  • Bushra Khattak asked a question in Restriction Enzyme:
    How to sub clone MYC tag Over expression Vector and use which method and restriction enzymes to digest it?

    I am using pCUbi1390 over expression vector, while for MYC i use pAHC25. My gene of interest have KpnI, TaqI, HinfI, HindIII. So I have to clone both my gene of interest and MYC together in Over expression vector, as a C- terminal vector.

    + 1 more attachment

  • Imani Sohrab added an answer in Isolation:
    How do we test if a nematode isolated from insect is parasitic on humans? Can anyone help us to screen this nematode?
    Entomopathogenic nematodes are used as bioagents against the control of insect pests in agriculture. We isolated a nematode which is easily multiplying on storage pest. We wish to cross check that this nematode is not parasitic against humans and other animals. Please help us to solve these doubts before we multiply the nermatode.
    Imani Sohrab

    in first step you may work on laboratory animals such as rat ,or mice.

  • Mauro José Lahm Cardoso added an answer in Diabetes Mellitus:
    Could Lactulose consumption worsen Diabetes mellitus?

    if yes by which mechanism?

    Mauro José Lahm Cardoso

    There are insufficient data to confirm that the use is harmful in the diabetic patient. However, the use must be restricted to those necessary cases as in hepatic encephalopathy

  • Ivo Carneiro de Sousa added an answer in Universities:
    What is the relation between income and college degree?

    If we look at the successful and rich people's life (e.g. Henry Ford, Thomas Edison, Bill Gates, Steve Jobs and Michael Dell etc.)

    We can understand that most of them expulsion from the university or dropping out university and they never graduate from the university. While everyone of them are the richest people in the world.

    And this conflict very surprised me.

    If we look through in their life we get they prefer to get success and riches use the experience of the other people instead of graduating the university.

    In your opinion, is it right that the university just educate the specialist that they work for the others??

    If they leave the university and find their ideas like Bill Gates can they successful in their job like Bill Gates or not??

    Ivo Carneiro de Sousa

    This a quite interesting and important question. The problem is not remotely related with success but with knowledge since those examples stress that there are areas, groups, companies, individuals, etc, able to produce knowledge faster and with much more social impact than universities. In fact, nowadays areas as business, design, informatic, etc, are producing new knowledge and new products ahead of university much slower researches. So, the key question is if universities can still produce knowledge ahead of social and economic changes. In those cases from Ford to gates one finds a rare combination of new knowledge, innovation and opportunity. 

  • Altaf Hussain Langrial added an answer in Islamic Studies:
    Research in islamic studies : modeling islamic practices ?

    dear friends,

    i am particularly interested in :

    Modeling Islamic principles, practices, and rituals (Islamic Law, prayer, fasting, inheritance, society, culture, history, islamic life plan, islamic finance, and other possible ideas), using Information technology techniques (specially UML, and java).

    Is there anyone interested ?

    amine baina

    Altaf Hussain Langrial

    Wow its a very goof idea. I am also thinking on it since many years. It will be contibution to the humanity. I will feel pleasure if there would some service for me please

  • Subir Bandyopadhyay added an answer in Tigers:
    Does anyone knows any researcher /organization working in Buxa Tiger Reserve?

    Please share contact details of a researchers/organizations working in Buxa Tiger reserve

    Subir Bandyopadhyay

    Dear Nishith,

    You can also contact Gopal Krishna <gopal_bsi@yahoo.co.in> and Anant Kumar <anantamu@gmail.com> who are involved in floristic studies of Buxa Tiger Reserve for  their Ph.D. They are both from Botanical Survey of India.

  • Gabriele Mirschel added an answer in Resveratrol:
    What can be the reason for a big difference between predicted and actual values in quantitative calibration by NIR?

    I performed the quantitative calibration (PLSR method) by NIR Spectrometer (Pharmatest IM 100) to measure  the concentration ( in range of 0.02-0.5 mg/ml) of Resveratrol  als drug in an Ethanol-Water (1:2) solution . The value of  Multiple correlation coefficient is 0.96 and standard error of estimate is 0.05. I performed the Prediction for new known solution to test the  calibration but the result is totally unacceptable and there is a big difference between the predicted values and the actual values and there isn’t any chance of prediction. 

    I guessed maybe the calibration is overfitted and I tried to carry out the calibration again by smaller range of Wavelength but the result was the same, any one have an explanation?

    Hope someone can help me.

    Thank you in advance for you answer.

    Gabriele Mirschel

    Dear Zahra,

    I believe there are different  lab conditions during calibration and testing the calibration.  The measurements conditions during calibration  must be adapted to those of later experiments. Otherwise,  a correct prediction is not possible.

    All the best,


  • Mathavan Muthaiyan asked a question in Viral Infection:
    Gene expression and biological impact?


    How do we understand the amount of gene expression level and biological impact

    for ex: some gene respond to the viral infection with only minor changes that still biologically relevant vice versa dramatic changes may be biologically irrelevant.

  • Alok Singh Chauhan added an answer in Warpage:
    Shrinkage and distortion in Gel Casting?

    Hello, what is the range of shrinkage associated with gel casting process. Since in general this value seems to be high, how can warpage or distortions be predicted and tackled properly? 


    Alok Singh Chauhan

    Hello there thanx for responding. I am referring to gel casting of ceramic material. It has been shown that this process can be used to get turbine rotors of ceramic material... The shrinkage ,I am enquiring here is during the drying and sintering stages of the process.  Just wanted to know advantages of gel casting process over ceramic Injection process as far as turbine rotors are concerned.


  • Xiaofeng Chang added an answer in Nanoparticle Research:
    Why does Pulsed laser ablation in liquids result in defect free nanoparticles?

    Why does Pulsed laser ablation in liquids result in defect free nanoparticles?

    Xiaofeng Chang

    No impurity does not mean defect free actually. Defect free means almost perfect crystals without defects, dislocations and even strains.

  • Marco Inserra added an answer in HEK293 Cells:
    Does anyone know a good serum (FBS) for HEK293 cell culture?

    We used to have "FBS Gold" from PAA. However, since they stopped production, we have big problems in seeing currents through TRPC3 channels using whole-cell patch clamping.

    Many thanks in advance!

    Marco Inserra

    Hi Michaela,

    I'm not entirely sure which species it's from or if the sell FBS from more than one species. Probably best to contact them. 

    We mostly do work on TRPV1 and TRPA1 but we have also worked with TRPC5 and TRPM8.

  • Sundaresan Muthuswamy added an answer in Consciousness:
    Is consciousness giving human beings an evolutionary advantage?
    While having the concept of Self as opposed to others or to the environment seems good for focusing the organism functions on survivability and on DNA spreading, is there any evidence that consciousness has an evolutionary advantage?

    To elaborate further, here I'm talking about consciousness as the first person experience. And for "first person experience" I'm not talking about "experience OF first person": conversly, I'm specifically addressing the "experience IN first person MODALITY" (as a corollary to this question, I'm proposing that the word "consciousness" refers to too many concepts). In this view, I consider self-consciousness "experience of first person in first person modality".
    If we embrace the assumption that consciousness is always consciousness of something, we still lack an explanation for the nature and the purpose ("what is/what's for" rather than "how is it") of the first person experience, and as such why evolution favored it.

    In a lot of other Q/A about self and consciousness people are talking about consctructs that may function even without consciousness. Two examples:
    -self: a neural network comprising semantic concepts about the world could very well include the concept of self as a non-other or non-environment, or even a concept of self as an independent organism with such and such features; why do we need consciousness to conceptualize it? Would a machine decoding all the concepts coming across the node of (or the distributed knowledge about) self be considered conscious? We do not have to attribute consciousness to the machine to explain the machine processing its concept of self.
    -thinking: processing is certainly different from consciously elaborate something, as all the studies on automatic and subconscious processing show. On the other hand, this point address the free will problem: when we consciously elaborate something, does it mean we are voluntarly doing so? Or are we just experiencing a first person "show" of something already happened subconsciously (as Libet's studies suggest)? Without touching upon the ad infinitum regression problems, this poses the question if consciousness is useful without free will: if the conscious experience is just a screen on which things are projected, no free will is needed and thus what's the whole point of consciousness? As such, do we also need free will for accepting consciousness? If we are working with the least number of assumptions, it seems unlikely the we can accept consciousness.

    It seems to me that the general attitude of cognitive theories in a biological information processing/computational theory of mind framework is to try to explain everything without putting consciousness in the equation. And indeed it seems to me that no one is actually putting consciousness in the equation, when explaining cognition or behaviour (at least in modern times).

    All in all, it seems to me that all the above reasonings bring the suggestion that consciousness is not needed and has no evolutionary advantage over automatic non-conscious entities. Or that we should make more and more assumptions (such as accepting free will) to make sense of consciousness.
    I think that asking why we have consciousness could lead us to understand it better.
    Sundaresan Muthuswamy

    @Louis Brassard ·.

    Thank you. self enacting is new thing i  learnt.

  • Mauro José Lahm Cardoso added an answer in Ketone Bodies:
    What are the procedure and methods for estimation of fructose, calcium, cholesterol, ketone bodies , only from the tissue not from blood or urine?

    what are the standard procedures ....

    I have gone through several papers but I didnt find specific  procedures .. 

    Mauro José Lahm Cardoso

    Ketone bodies can be measured in urine or blood. In urine using reactive strips and apparatus for measuring blood have B-OH butyrate. The cholesterol and fractions best method (more precise), regardless of type, is electrophoresis. But the total cholesterol and total calcium can be measured by dry chemistry.

  • Imani Sohrab added an answer in Analytical Environmental Chemistry:
    Has anyone any data on dichlorvos in water or how rapidly it breaks down under different conditions?
    We are interested in whether dichlorvos poses any risk to drinking water, particularly in developing countries.
    Imani Sohrab

    dichlorvos rapidly breaks in water condition , it is sensitive against hydrolytic condition,I like to work about its metabolite in drinking water.

  • Daniel Alejandro Perez asked a question in Probes:
    Late amplification at ~35 cycles, RT PCR?


    I am seeing late amplification at about 35 cycles. Also, I believe that the difference in expression curves is due to not having normalized my templates (not certain, could be completely wrong).. I did not have a Qubit to measure some of the cDNA controls that were made before my time in the lab. I was able to normalize the other cDNA samples at the RNA level before reverse transcriptase.. 

    Ct values range from 26-35 (not sure if this helps for this question) 

    Image attached. Please help :) thank you! 

    P.S. -- using SensiFast, Hi-Rox Probe kit from Bioline with TaqMan gene expression pre-designed probes and beta-actin endogenous controls. 

    Cycling conditions: 1X at 95C for 2 minutes, (95C for 10s, 65C for 30s)X40 

  • Ram Narayan Yadav added an answer in Graph Algorithms:
    How can I devise an algorithm which generates all possible edge disjoint spanning tree of graph G?

    Let G be an undirected graph with n vertices and m edges, such that each edge has a real-valued cost.  How can we devise an algorithm which generates all possible edge disjoint spanning tree of graph G ?

    Can someone provide me the article entitled as "A Note on Finding Maximum-Cost Edge-Disjoint Spanning Trees" by J. Roskind and R. Tarjan, Nov. 1985 ?

    Ram Narayan Yadav

    Thank you Albert sir.

    So, the above mentioned algorithm will list all possible edge disjoint spanning tree in O(V(V+E)) time.

  • Adam A. Scaife added an answer in Climate Data:
    Does anyone know a very high resolution gridded database of daily precipitation for China?

    I need DAILY precipitation dataset at a resolution around 30 arc-seconds (~1km) for China, covering the period of 2000-2014. Is there any?

    I would appreciate every single recommendation.

    Adam A. Scaife

    Hi Neda

    As well as the global reanalyses there are at least two high resolution data sets specific to this region which use local rainfall observations:

    APHRODITE: http://www.chikyu.ac.jp/precip/products/index.html


    PERSIANN: http://chrs.web.uci.edu/persiann/data.html

    I am not sure of the quality of these but they both cover your region of interest.  They are well documented and are high resolution but I don't think you will find anything at 1km resolution. 

    I recommend you consider both to account for observational uncertainty and also consider the lower resolution GPCP dataset: http://www.esrl.noaa.gov/psd/data/gridded/data.gpcp.html



  • Ayuob Aghaei added an answer in Graphene Quantum Dots:
    Is there any practical way to synthesise graphene quantum dot with IR peak nIR region?

    As you know graphene quantum dots have luminescent properties. I'm looking for an applicable method which yields graphene QD with emission in IR or NIR  region!

    Ayuob Aghaei

    You can use follow articles:

    Fabrication of highly fluorescent graphene quantum dots using L-glutamic acid for in vitro/in vivo imaging and sensing. DOI: 10.1039/c3tc30820k

    Three Colors Emission from S,N Co-doped Graphene Quantum Dots for Visible Light H2 Production and Bioimaging. DOI: 10.1002/adom.201400549

    N, S co-doped graphene quantum dots from a single source precursor used for photodynamic cancer therapy under two-photon excitation. DOI: 10.1039/b000000x

    minFluorescence Carbon Nanoparticles Derived from Natural Material of Mango Fruit for Bio-imaging Probes. DOI: 10.1039/C4NR04805A

    Quantum-Sized Carbon Dots for Bright and Colorful Photoluminescence. DOI: 10.1021/ja062677d

  • Thanmayi Chowdary asked a question in Column:
    Can anyone suggest an ideal protocol for purifying spin column?

    We want to re-use a spin column for our project..
    How to purify the spin column to use it again..

  • Nur Zuraihan asked a question in PPM:
    How to calculate vapor concentration of gas inside the chamber, for gas sensor application?

    I have refer based on two articles. there are two equation on how to calculate the vapor concentration Cg (ppm) inside the chamber :

    1) C (ppm) =   CxVxdxRxT   x 10        

    2) C (ppm) =     VxdxRxT   x 10^6


    C: Concentration of liquid analyte

    V: volume of liquid injected

    R: universal gas constant

    T: absolute temperature (K)

    M: molecular weight

    P: chamber pressure

    V: volume of chamber

    My question is what does the x10 and x10^6 represent? Why there have two different value there?


  • Daniel Valim added an answer in TEM Image Analysis:
    How can I calculate the number of walls in MWCNT from TEM images?

    Using the interatomic distance. Please, if there is a reference, I'll be grateful.

    Daniel Valim

    If I'm not wrong, Raman spectroscopy is more adequate tecnique to ask this question. Search works of M. Pimenta or A. G. Souza Filho.

  • Pranav Tiwari added an answer in PCL:
    How I can hydrolyses gelatin fiber?

    I am making core shell nanofiber with shell as PCL and core part is gelatin. After that I want to make a hollow kind of structure such that remove the gelatin. So is their any chemical method to hydrolyse the gelatin.

    Pranav Tiwari

    Thanks sir

  • V.s.V Mani added an answer in Circuits:
    Can we call it a non-inverting summing amplifier?

    Inverting summing amplifiers are well known. However, attached is a circuit with two versions. The first gives an output from the amplifier that is equal to the average value of three input signals. The second gives an output equal to the sum. The topology can be extended to higher inputs, but I cannot recall it being documented in text books on op amps. Can it be called as a non-inverting summing amplifier ?

    V.s.V Mani

    I prefer the inverting summer for summing as it is non interactive. the 'gain" of other channels are not affected when I change the weightage resistor for the channel of interest. This is due to the low input resistance of the type of feedback used in inverting summers, as low as Rf/effective Av. this might be just a few ohms and hence we are actually converting the voltage to currents and adding the currents finally producing a voltage using Rf. the noninverting average/summer is way different. If the sum is what is the output, what is the amplification factor? no doubt you can also have amplification of more than 1, by suitably changing the feedback resistor. The summer does not allow changing the contribution from each channel, an advantage obtained with inverting summer, without also, the interaction between various channel gains.