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  • 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

    Dr Deka days are not far off , when you have to consider the carbon budget of the whole cropping sequence in a   farming system .  Off course soil is considered to be a  better sink for atmospheric carbon to be sequestered. I request my learned colleagues to share their experiences on this very important issue, since our  current state of knowledge on this issue  in  Asian context is still in a developing stage. Let me share some very useful information about perennial crop like citrus , as to what an extent , such perennial crops could serve the environmental sustainability , besides income generating and livelihood earning cash crop . In Spain , in 12-year-old Valencia orange trees , it was estimated that trees can fix 50 kg C per tree per year, out of which fruits and new flush  leaves  accounted for more than 75%, and only rest of the  25% were sequestered by old branches , trunk and tap root. Leaves fixed total C of 15.4 Mg C per ha per year , with loss of C through respiration of about 2.7 Mg per  ha per year, thus  establishing net surplus of 12.7 mg C per ha per year. I am enclosing the relevant PDF for your reference please .

  • Ngoc Thuy Vo Thi added an answer in Quantum Dots:
    When I conjugated quantum dots with antibody, their sizes incresase somuch (from 4nm to 900nm). Pleased help me explain that?

    T. V. Torchynska

    Ngoc Thuy Vo Thi

    Thank you for your responese. May you be right but  Is it due to the MPA, EDC, NHS and AB that i had conjugated?

    I conjugated quantum dots with AB E.Coli O157:H7.

  • Rodney Rosalia added an answer in DCS:
    Are splenic pre-DC depleted in CD11c-DTR mice (Jung et al., Immunity. 2002 August ; 17(2): 211–220) after DT administration?

    In the BM, DT administration seems to deplete all BM-derived DC precursors (Meredith et al., J. Exp. Med. Vol. 209 No. 6 1153-1165), my guess would be that splenic pre-DCs are also depleted in CD11c-DTR mice.

    However, using an alternative model, the CD11c-DOG (Hochweller et al., Blood. 2009;
    114:4411-4421) it is suggested that splenic pre-DCs are not fully depleted after DT administration but reduced by 75%, presumably because splenic-pre DCs express lower levels of CD11c (compared to fully differentiated DCs).

    Could anybody assist me with this issue/question? 

    Rodney Rosalia

    Dear Ibrahim, thanks for your reply.... I would like to know whether splenic CD11c+ pre-DCs are depleted upon DT administration in CD11c-DTR mice?

    Hope this clarifies the question...

  • Hemanta Kalita added an answer in Oils:
    Please suggest an instrument that can measure the polarity and/or dielectric constant of oils?

    I need to compare between oils with respect to their polarity. I need help in identifying an instrument that can do a quick measurement. Can a conductimeter be used with oils or is their a separate instrument that measures dielectric constant? Please suggest an instrument that I may be able to use to get data on oil properties.

    Hemanta Kalita

    This research paper may help you. Anyway, I have attached the same.

    Macedonian Journal of Chemistry and Chemical Engineering, Vol. 31, No. 2, pp. 285-294 (2012)
    ISSN 1857-5552
    UDC: 537.226.2:664.3

  • Mehdi Amiri Nasab added an answer in Wireshark:
    How can I see or analyze packet loss value in wireshark?

    Dear all,

    I have to analyze throughput, packet loss and delay for LTE network using crawdad data. Now I have crawdad dataset tested on Wibro. This dataset has given pcap file. And I open this pcap files by using wireshark. I am beginner for wireshark. So if anyone knows, please give me guidelines how to see packet loss value in wireshark.

    thanks all

    best regards

    Mehdi Amiri Nasab

    or the packet loss you can then append the conversation filter with "and tcp.analysis.lost_segment", then look at the status bar to see how many packets match the filter ("Displayed:" value).

  • Vlad Kropelnytskyi added an answer in Cervical Cancer:
    How should we stage cervical cancer with ovarian metastasis? T2b? M1?

    Squamous carcinoma of the cervix (2 x 0,8cm). 

    Left ovary - micrometastasis, tube - N

    Righ adnexa - N

    LN - metastasis (right  1/5, left 0/5).

    What will be the pTNM?

    TNM-book doesn't clarified ovarian metastasis.

    Vlad Kropelnytskyi

    In this situation there is no direct spread. There is separate metastatic small squamous carcinoma nodule in the ovary. Parametrial tissue without direct invasion.

  • Mario Hirz added an answer in Intelligent Systems:
    Do you need always a knowledge in order to achieve a task?


    I am wondering if it is always necessary for an intelligent system to have knowledge in order to achieve a task automatically? 

    Hope that my question is clear!

    Thank you

    Mario Hirz

    This is a very interesting question, which has a relation to the development of self-learning systems. To discuss this topic, the term "... to achieve a task automatically" has to be defined more accurate. Knowledge for solving a problem may come from different sources, e.g. experience, libraries, experts. The achievement may include the process of gathering knowledge, and after that the process of finding a solution. In this way, self-learning systems should have the capability to search and to find that information, which is required to solve a specific problem. And they sould have the capability to solve the specific problem by use of knowledge, and the application of solving-methods.

    Kind regards,


  • Vasile Surducan added an answer in Electronic Amplifiers:
    Which terminal of the transistor in the circuit of a phase splitter is common?

    In the circuit of an emitter follower, the collector of the transistor is firmly fixed to VCC... and, regarding the AC variations, the collector is AC fixed to ground... it is AC grounded. Thus the ground terminal of the input source, of the load and the collector as though are joined in a common point... hence the name of this configuration - common-collector stage. So, let's repeat it, in a common-collector configuration the collector is fixed, "immovable" since it is connected to a "firm" voltage source...

    Now let's insert a resistor (RC) between the collector and the power supply (as in the well-known circuit of a phase splitter in the attached picture below)... and continue using the emitter voltage VOUT+ as an output. The transistor will compensate this disturbance by additional decreasing its instant collector-emitter "resistance" RCE so that the total sum RC + RCE (and accordingly the collector current) does not change... but the collector voltage (VOUT-) will decrease and will no longer be equal to VCC. So, the new circuit will continue to be an emitter follower... indeed, a disturbed emitter follower... but still an emitter follower...

    But is this circuit a common-collector stage since the collector is no longer a common terminal? I don't think so. It is an emitter follower but it is not a common-collector stage...

    So, it turns out there is a basic transistor circuit where the transistor has no common terminal... no one of its terminals is fixed... all they are "floating"... Then how do we classify it? To classify it, we need to see the common terminal... but what is common here?

    How would you comment this discrepancy?

    Vasile Surducan


    In my humble opinion, any electronic components lab in any serious university should began with this simple moment: throwing a bunch of components (hundreds) on the table and teach the students a few hours what they see. This should be an eliminatory test before any exam.

    Then teach them how to distinguish a defective BJT using a simple multimeter, how to determine correct the terminals on various standardized packages (including the super miniaturized sizes).

    How to determine if a MOSFET is good or bad using only a multimeter.  Of course at the end perhaps will not be bad to mention that BJT becomes faster an obsolete device, being replaced by IGBT, MOSFET, GTO or SCR in power electronics and very soon in everyday electronics.

    It does not count (so much as teachers are believing) the transistor equations, neither the characteristics as long the student understand how it works. This is the true problem. :)

  • Xin Huang added an answer in Nanogenerators:
    Triboelectric nanogenerators - are there any devices on the market?

    Can devices based on triboelectric nanogenerators are already in the process of commercialization? Any the test versions, development kits for mechanical energy harvesting (converting the external kinetic energy into an electrical energy)?

    Xin Huang

    I can`t imagine any commercial prospect of triboelectric nanigenerators. I think the so-called triboelectric NG is just at the initial stage of experimental design for paper publishing or maybe toy invention for fun, anyway, just my own opinion.

  • Mehdi Amiri Nasab added an answer in Routing Protocols:
    What is the relation between ETX as an OF and Path Cost in RPL protocol?

    In RPL (Routing Protocol for Low Power and Lossy Networks) we can use ETX (Expected Transmission Count) as an OF (Objective Function) for rank computation.

    Can anyone explain the relation between ETX and Path cost in RPL?

    Mehdi Amiri Nasab

    hi my friend . you can see calculate about etx in this file in contiki operation system . rpl-mrhof.c. 

    if you want know about etx as on of i think this file help you .

     best regard.

  • Seyed Hadi --- Khatami added an answer in OCP:
    What kind of comparisons we could have based on OCP values?

    if I have OCP values before and after Rp/Ec trend for two type of steel, could I use these values to make comparison which one will corrode firstly (more positive is noble and more negative is more active? or what kind of comparison we can have?

    Seyed Hadi --- Khatami

    My Dear fist of all tell me what is OCP and I will guide you which test you can use.

  • Markus M. Becker added an answer in Comsol Multiphysics:
    How can I deal with this comsol error?

    Hi,dear friends.I'm now trying to solve a transient electromagnetic field problem using COMSOL Multiphysics.But when I build  the mesh,it shows :

    Failed to generate mesh for domain.
    - Domain: 7
    Failed to insert point.
    - x-coordinate: 2999.28
    - y-coordinate: -19.7869
    - z-coordinate: 0
    An empty cavity was generated.

     And I also split the mesh from small to large order ,but it still shows errors.So how can I modify my model so as it can build the mesh well?

  • Seyed Hadi --- Khatami added an answer in Basic Statistical Methods:
    What statistical test should I use to compare total fish catch?

    I am looking for a statistical test to compare the amount of fish catch between 2 rivers.


    River 1 caught a total of 200 fish

    River 2 caught a total of 15 fish

    Is there a test that will show if there is a statistical difference of total fish caught between river 1 (200) and river 2 (15)? My thought is to use a chi-squared test. Does this sound correct?

    Seyed Hadi --- Khatami

    Dear Juan Pablo Carrascal ,

    It depend on you result that are normal distribution or not. If they are normal you can use T-test or ANOVA, if they are not normal you can trasfer data, use T-test or ANOVA, but if they are not to be normal use U-test if you have got at least 4 sample for each river or use Kruskal-Walis test.

  • Upeksha Perera added an answer in Publications:
    Is there publications on open calculation based of number ABN ?

    I need publications on method ABN created by Jaime Martinez Montero, thanks a lot 

    Upeksha Perera

    try this one out:

  • Erling Næss added an answer in Mass Transfer:
    Anyone familiar with mass transfer coefficient and velocity effect?

    Hi all

    After a long time, i am in RG.

    I am having a fundamental understanding problem about the effect of velocity of fluid on mass transfer coefficient.

    As we know that as velocity increases, mass transfer coefficient increases because of fresh fluid elements coming into the mass transfer interface.

    If fresh fluid elements come to the interface, then mass transfer driving force will be higher and consequently molar flux will also be higher. If the velocity is further increased, driving force and consequently flux will further increase. That means mass transfer coefficient remaining constant.

    How fresh fluid elements increases mass transfer coefficient then? How to understand it physically? 


    Vivek Arora

    Erling Næss

    The mass transfer coefficient is defined by the concentration difference between the wall and the bulk as driving force. These may of course be kept constant while changing the fluid velocity. However, the amount of mass transfer (i.e. the mass flux) will affect the mass transfer coefficient due to the added mass introduced into or removed from the boundary layer at the interface (so-called 'blowing' or 'suction'). Both will influence the concentration profile in the boundary layer. Simplistically, 'blowing' will thicken the boundary layer and reduce the mass transfer coefficient, and 'suction' will have the opposite effect. Consequently, the mass transfer coefficient depends on the direction and magnitude of the mass flux. The driving force may remain unaffected for these situations.

    Many mass transfer problems involves phase change (e.g. evaporation, condensation or sublimation) at the interface. This means that there is heat transfer in addition to the mass transfer. This may involve heat transfer between the interface and the flowing fluid (e.g. air), and the heat transfer coefficient is of course affected by air velocity change.  For such cases the interface condition (temperature) can be influenced by the presence of heat transfer, meaning that the equilibrium  mass concentration concentration at the interface changes. Again, this is covered by the readings I suggested.

  • Ana Poveda added an answer in Cell Culture Techniques:
    How can I acquire mitochondrial DNA-depleted Rho0 cells?

    How do you acquire mitochondrial DNA-depleted Rho0 cells? I exposed cells to 50 ng/mL EB for generation of Rho0 cells, but nothing abnormal has happened compared to non-treated cells.

    Could anybody tell me some specific details about the whole process?

    Ana Poveda

    Hi Dominique,

    I am also interested on generating these rho0 mutants. Can you tell me the DAPI concentration needed to stain mtDNA on yeast? 


  • Shubhneet Kaur added an answer in Nano Biomedicine :
    How to dissolve pva 100% hydrolyze in water.
    I need to dissolve 100% hydrolyzed PVA in water. I dissolved 87% PVA in water with little heating and stirring for 2 hours. but 100% PVA I can't dissolve it even with same heating.
    Shubhneet Kaur

    Hi, Islam can u please let me know is there any difference between PVA (Hot) and PVA (Cold)

  • Hafiz Shehbaz Ali added an answer in Image Processing:
    Can anyone recommend software for image processing other than matlab?
    I am doing research on image processing and its application in the military.
    Hafiz Shehbaz Ali

    How about the R statistical computing language which is open source and has bundle of packages.  I think, it is better Idea to use R.  A large research and scientist community is migrating towards the R.

  • Ahmed Elsayed added an answer in Temperature:
    Why when I decrease the flow with superdex to 0.1 or 0.05,, after few runs with that flow-rate, the pressure is increasing?

    And once the pressure getting so high with the low flow rate, then I increase the flow rate to 0.3 then 0.4 ml/min and change the Pressure alarm value, at that time the pressure decrease to the normal level but it takes some time, that happening with pure water , or reversed-column, and finally I have tried it with 0.5M NaCl, and another run with 1M NaOH, and the same problem still there.

    I got same problem with Superdex 200 10/300, and 200 5/150, and 75 10/300.

    Low flow-rates usually gives me the highest resolution for my samples.

    I am not using protein, I just use DNA and RNA samples.

    The filter on the top looks okay, not dirty.

    No gaps between the filter and the beads.

    The temperature is between 23-27 (room temperature).

    No other clogs in the system, I am using Akta-purifier, only the pressure start read once I connect the column.

    I filter my solutions using 0.2micro, some times I double filter it, and also degas it for over 5min some times 10min.

    I will appreciate if some one give me any explanation about that.

    Thanks in advance...

    Ahmed Elsayed

    Dr. Viktor Y Butnev 

    Thanks for your reply. At the beginning I thought the system could have some troubles, but whenever I run the system without the column it works fine, and the pressure is 0 with the flow rate 0.5 (I did not check more than that flow rate), even with the same length of wire-tube connections that I use in the presence of the column.

    But, actually now I searched the back pressure, and I found it has some relation with the system in several ways, I got  some useful information about it, including the flow restrictor. I will try all those advices and see what will happen.

    Thank you so much,,

  • Anbarasa Pandian asked a question in Image Retrieval:
    Is it possible for Color feature extraction using Brain image (gray scale image) ?

    I am doing work in image retrieval using brain image (Gray scale image). My concept  is Texture, color and shapes feature extraction process going to do.

    Is it possible for finding color feature in brain image but it is gray scale image not color image.

    Please suggest me friends or any idea friends...

  • Preethi Sekar added an answer in Geotechnical Engineering:
    What are the required parameters to perform dynamic analysis of soil-structures such as embankments, earth-dams, and retaining walls?
    Can PLAXIS perform such kind of analysis with acceptable reliability?
    Preethi Sekar

    In the recent version of plaxis, they have included an option called dynamic load and it asks for the amplitude and the frequency of the wave through the soil and the direction of application. a similar example has been explained in the tutorial manual for a normal multi-storied structure. 

  • Mario Hirz added an answer in Computational Fluid Dynamics:
    Regarding CAD geometry for computational fluid dynamics simulations: How do I ensure "watertightness"?

    I create CAD files in a CADing software and need to import them into a meshing software for my CFD simulations. Cracks appear in the geometry during the process.  A micron level confirming to boundaries is essential. It is therefore too difficult to find all such cracks manually and repair them. I have a centimetre sized object.  Looks like the appearance of cracks is inevitable and softwares do not seem to provide an automatic size based crack repair (understandable, as the software is supposed to mesh, not repair boundary mistakes) Proving to be a real spot of bother. Thanks in anticipation.

    Mario Hirz

    If you have an STL file, you can convert the STL file to IGES. Then you have a surface model with a big number of surface elements. These surface elements can be merged and after that, the merged surface model can be converted to a solid model by use of a Fill-Function. It might be a problem, that the IGES file has some "open" surfaces, so that the merging and filling process does not work automatically. In this case, the open surface spots must be repaired by hand, or you can adjust the computation tolerance in a way, that the failure distance is not considered by the system anymore.

    Another possibility is to use automated repair functions in the CAD system. CATIA provides a "HEaling" funktion in the workbench Generative Shape Design. With this function, it is possible to repair failures of surface models.

    Kind regards,


  • Mohammed El-Bialy added an answer in Geochemistry:
    How to interpret positive Ba anomaly with negative Eu, Sr, Ti, Nb and Ta anomalies of biotite-hornblende granite?

    How to interpret positive Ba anomaly with negative Eu, Sr, Ti, Nb and Ta anomalies of biotite-hornblende granite? 

    + 1 more attachment

    Mohammed El-Bialy

    The positive Ba anomaly is typical of EM1 mantle component source and is conversely uncommon in crustal material. Therefore, I guess this may imply participation of mantle material in the source.

  • Sushanta Kumar Bhowmik added an answer in Profit:
    In Capital Economy, investment is for profit and this profit has no limitation; then why there is cry of 'Anti-corruption' laws and systems?

    We know the development of present civilization based on Capital Economy. Capital economy is a system of profit against investment amount that is capital. An investor tries to gain best profit that means no-limit. Then the investor will do possible all steps to gain most. So far, it is not 'Corruption'. An investor can buy a village, a town, a city as per law is not corruption. Even the unaccountable accumulation of money of this investor is not a crime as per rule. Then, where is corruption? And, if there is not corruption; then why is the cry of 'Anti-corruption' laws etc.?

    Sushanta Kumar Bhowmik

    Dear Israr, Your explanation is justified and it requires more response from others.


  • Krishnan Umachandran added an answer in Process and Product Innovation:
    Any suggestions on a measurement scale for different kinds of innovations?

    I am  investigating the business innovation approaches adopted by the entrepreneurial in the retail sector of Malaysia. Kindly guide me or help me with some relevant articles on measurement scale for different types of innovation such as business innovation, marketing innovation, product and process innovation etc.

    Krishnan Umachandran

    A simple innovation dashboard

  • Muayyad Ahmad added an answer in Missing Data:
    How do you differ "missing data with ignorable mechanism" and "missing data with non-ignorable mechanism"?

    Little and Rubin (2002) introduced three major missing data mechanisms. If the cause of missingness is independent of data, missingness is called missing completely at random (MCAR).  On the other hand, in missing at random (MAR) mechanism, missingness depends on data which is observed yet independent of the unobserved data. Finally, third mechanism termed missing not at random (MNAR) because the pattern of missing data is non-random and depends on the missing variable.

    According to the literature, you cannot ignore missing data which is "Missing not at random" (MNAR). My question is: given a dataset, how do you identify the missingness mechanism?

    Muayyad Ahmad

    This is a very important question. Researchers should examin the pattern and volume of the missing data before doing the final analyses. runing descriptive statistics can show where are the missings, so the researcher can look at the cases and the variables and observe any pattern or volume of missings. for example, if the same question has a large amount of missings, then there is a possible problem in this question that the participants did not understand, or did not like, or the question was unclear by wording or typing.

    Usually Missing at random is better than non random because at random means that the missings is distributed over the different variables in small scale and can be replaced by many methods {Replacing missing is an Art and it take long time to be mentioned here}. however, if the missing is estimated to be too much, and this too much depends on the sample size and the type of the study, then missing becomes a serious problem.

  • Santimoy Khilari added an answer in Graphene Oxide:
    Which substrate should I use with graphene oxide to measure the thickness of graphene oxide by using SEM technique?

    thickness of graphene oxide by SEM

    Santimoy Khilari

    It is better to do AFM for thickness measurement of graphene oxide or graphene sheet. If you want to measure thickness from SEM study it is better to use Al foil or Si wafer as substrate for solution dispersed GO sheets.

  • Anoop Kumar Srivastava added an answer in Manure:
    How can we elevate the crop response efficiency of organic manures?

    Organic manuring is known as  an age old agricultural practice . But ,  its relevance in modern day agriculture is proven beyond doubt in the context of iheir multiple roles, including as nutrient source and cleanser of soil contaminants, besides improving soil physico-chemical and biological properties, with the result, crop performance is holistically improved.In this background, i call upon my learned colleagues to respond to my following querries, which will go a long way in clearing some of the intricate issues related organic manuring:

    * What is the effectiveness of different organic manures,  considering their utility as nutrient source versus soil amendment?.

    * Do we need to evaluate salt index of manures to define the quality of different manures?.

    * Whether the quality criteria of agiven manure differ according to type of substrate undergoing composting/.

    * To what an extent , manures alone are effective as compared to in combination  with mineral fertilizers?.

    * Do we need to load the organic manures with PGPRs to improve their responess?.

    * How effective is organic manures in cleansing the soil contaminants/pollutants ( Sieve function of soil ) ?.

    * Which is the best method of organic manuring in perennial trees?. 

    Anoop Kumar Srivastava

    Dr you have raised another  very pertinent issue . Yes, perennial crops by the virtue of long juvenile phase , perennial framework acting as perennial source of  nutrient reserve, and   nearly 250-280 days  of  annual growth cycle , hold much higher potential for better response of  nutrient source, either organic or inorganic in nature . Annual occurrence of root flush followed by shoot flush also triggers off better nutrient demand through  excellent vascular system between underground root system and  above-ground shoot system .   

  • Norris F. Krueger added an answer in Intentionality:
    What is Shapero model of Entrepreneurial Intention?

    I just came across the  this model that considers Perceived desirability
    Perceived feasibility . Can anyone please explain how does these two parameters affect the intention?

    Norris F. Krueger

    Essentially, Shapero used Perceived Desirability to cover Ajzen-Fishbein's Social Nornms & Attitude; Perceived Behavioral Control is not exactly the same as Perceived Feasibility and Shapero adds Propensity to Act (that is more of a Person variable, not PxS like the others.