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  • Dhananjay Singh added an answer in Civil Engineering:
    Urban Flooding in HEC-HMS??

    Hi all, I am working in Urban Flooding in HEC-HMS Software of Andhra Pradesh Industrial Area. Can you suggest some procedures required in the HEC-HMS after delineating the Area. Can you tell me the steps required to run the software.

    Can you suggest how I can analysis of that industrial Area??

    Dhananjay Singh

    Can you meet me pls for discuss.

  • Manjunatha Hanumanthappa added an answer in Epithelial Mesenchymal Transition:
    Which is the most suitable cell lines to study TGFb induced Epithelial to mesenchymal transition(EMT)?

    I am planning to find the Hub protein using protien-protein interaction through in-sillico apporach. For that which is the most suitable cell lines(tumor).

    Manjunatha Hanumanthappa

    I am very thank full for your kind suggestions

    Mr. C.R. Naveen Kumar  and  Mr.Ruhul Amin

  • Frank Veroustraete added an answer in Hyderabad:
    Hii All, I am working of Urban flood aspects of Hyderabad City, India. I was trying to analyse the urban flood scenario for future rainfall trend ?

    Hii All, I am working of Urban flood aspects of Hyderabad City, India. I was trying to analyse the urban flood scenario for future rainfall trend. where can i find the estimated future rainfall trend without using GCMs and down scaling techniques, I s there any other option or is such data available.

    Could you please help me out with this.

    Frank Veroustraete

    Just Google Simclim and yo will learn all about it Swathi. I guess thta's the tool you need for Hyderabad or India for that matter.



  • Anil Kumar added an answer in Climate Data:
    How do I convert rainfall rates from "mm day-1 50 yrs-1" to mm/year?

    I have estimated a decreasing trend in wet-season precipitation for a tropical-forest site in eastern Guatemala using real climate data (and regression), as -59.9 mm/year (between 1992 and 2009), and want to compare this value to other tropical sites. In an IPCC report, a decrease for Central America is estimated as “-1 mm day-1 50 yrs-1” (I copied it literally), and in a recent paper in PNAS, it is stated that “The model median amplitude of this trend is between 0.5 and 1 mm day-1 per 100 yr over most of the (Central American-Caribbean) region”. My question is, how do I transform these values to mm/year? I don´t understand the units of the cited data to make the calculation myself. Thank you climatologists!!

    Anil Kumar

    i agry with Douglas Sheil reply for Alexis Cerezo Blandón question.

  • Qamar Farooq added an answer in Physics:
    "Quantum chemistry" (MCQuarrie)?

    I need this book: "Quantum chemistry" - MCQuarrie and its solution manual.

    Qamar Farooq

    Patrick kindly check your email ! Sent it to you

  • Anoop Kumar Srivastava added an answer in Aquaponics:
    Why do salt affected soils continue to pose potential threats to food security?

    Salt affected soils globally cover over 800 million ha (8-10% of of world land area), with a significant proportion of cultivated land is  salt affected . Such soils are characterized by salinity and sodicity of various demensions , the origin of which can be traced either geogenic or lithogenic or even combination of both. It is uncommon sight  to see , a soil once reclaimed is put to use for better crop production and added to the  main stream of  cultivated soils , though  still called as reclaimed soils. In this background , i put up following questions to my learned colleagues to contribute handsomely and benefit all of us:

    *Why dont we consider calcareous soils as a part of salt affected soils  ?

    * Why salts do not accumulate in grains or edible parts of plants ?. What are the mechanistic insights for such physiological events? 

    * Do we have sensors to  directly measure the salinity and sodicity in field? Or , alternatively , Is there any field diagnostic kit available for appraisal of salinity or sodicity right in the field?

    *Which type of reclamation is more sustainable from environment point of view?

    * How do you see the role(s) of salt tolerant microbes in reclamation and post-reclamation scenario of salt affected soils?  

    * What is the best method of artificial recharge of ground water?

    * What is the system of rice intensification , and what magnitude of success , it holds in salt affected soils?

    * How do you see the success of bio-saline agriculture ? Is saline aquaponics  potentially promising ?

    *How do you see the emerging issues on salinity and sodicity getting vitiated by consequences of climate change? How shall we reorient our objectives in this context?

    Thanks and regards 

    Anoop Kumar Srivastava

    Abhshek , thanks for putting up some finest material , most relevant to the on-going discussion . Let me add some more material from these enclosures for the benefit of the followers  of the discussion : 

    Soil salinization and sodication have been identified as major processes of land degradation and loss of agricultural production.The high costs of measuring salinization and sodication, as well as inconsistencies in data collection and reporting methods, have resulted in incomplete – and often contradictory – information on the extent and distribution of salt-affected soils at country, regional and global levels. The causes of salinity/sodicity, which vary between countries and regions, need to be identified, assessed and monitored carefully so that they can be managed and controlled. The few maps that show the extent of salt-affected soils are often based on old data and do not give a picture of the current extent of salinity, as data to determine the rate of change of salinization need to be updated regularly. Therefore, there is a need for practical and cost-effective methodologies for assessing, monitoring and mapping the extent and distribution of salt-affected soils; for assessing the causes and sources of the problem; and for choosing management options and evaluating the effectiveness of those options.


    "Advances in the assessment and monitoring of salinization and status of biosaline agriculture: Report of an expert consultation held in Dubai, United Arab Emirates, 26–29 November 2007".

    Soil salinity/sodicity, waterlogging and low soil fertility are serious problems at
    the global level and are present in the countries participating in the Consultation
    to varying extent and severity. Due to the high cost of measurements, the lack
    of data and the inconsistencies between data provided by various sources, there is incomplete information on the extent, distribution, rate and degree of salinity development for most of participating countries. In some countries, the existence of these soils was discovered only because of the pressing demand for agricultural utilization in specific areas. Few countries have up-to-date data on the extent of salt-affected soils.  

    Researchers and field technicians often lack funds, other resources and government support to enable them to work on issues related to salt-affected soils including assessment, monitoring and mapping.Human resources required to assess, monitor and map salt-affected soils are limited in most participating countries.

    Many countries lack systematic national procedures to monitor secondary
    salinization and sodication. Studies are done on an ad hoc basis. Reliable data to establish baseline conditions are also lacking.

    Depending on the scale, the different methods required for assessing and
    monitoring salt-affected soils in participating countries varied from simple field
    surveys, sampling and laboratory measurements, including electrical conductivity (EC) and exchangeable sodium percentage (ESP), to the use of expert assessment, salinity sensors, electromagnetic sensors, remote sensing, Geographic Information Systems (GIS) and modelling. Models require a very intensive effort for data collection and are not commonly  used in most participating countries. However, some countries do have standardized assessments, modelling and mapping methodologies and procedures that could be shared with other SPUSH members to improve classification and mapping of their salt-affected soils.

    Policies that relate to the management of salt-affected soils in the participating
    countries are often not effective. Most countries do not have a strategy or policy
    at national level for assessing and monitoring salt-affected soils.

    The available maps on the extent, severity and rate of salinization/sodication
    and waterlogging  need to be updated as they are based on old data. In this regard,  we need to  develop guidelines and a database on resource surveys and land use planning. This database must be maintained and updated regularly.

  • Vinay Mehra asked a question in Glutathione S-Transferase:
    Can anyone recommend a method to assay the activity of GST (Glutathione S-transferase)?

    I want to assay the activity of GST in camel, but I haven't any reliable method to do it.

  • Shazia Aziz added an answer in Critical Discourse Analysis:
    Any data for Critical Discourse Analysis and Linguistic Analysis of political speech?

    I want to analyse a political leader's speech linguistically and critically.The speech is not in English.Can you guide me what is the more reliable data source?Should I listen to the speech and translate it in English myself and then analyse it? or should I get an already translated (by someone) version of the speech in written form from internet and  analyse that? or something else?

    Shazia Aziz

    Thanks Laura.This too is a good idea.But the point is, he switches just to address the foreign audience, the super powers and gives them examples from their history to justify his stance.Otherwise in the Urdu part, there are switches to English only when specific jargon is concerned like SUO MOTO, etc.

  • Samir Chauhan added an answer in Gas:
    Ionization rate coefficients in magnetic field?

    The ion source term are often written as b*n*ne, where n and ne are neutral and electron density respectively. For argon gas and electron gas of 10 eV the rate coefficient 'b' comes out to be 2-3X10^(-14) m^(3)/s. Is there any way to include the effect of magnetic field in this rate coefficient. Magnetic field will (effectively) increase ionization rate and its effect in principle can be added in to the rate coefficient. Is there any reference which details how to actually do this quantitatively. (for given magnetic field)

    Samir Chauhan

    Magnetic field will enhance ionization efficiency by confining electrons and making more collisions possible. My argument is that if this effect can be emulated by artificially increasing rate coefficient in the ionization model instead of including magnetic field from first principle.

  • Sayan Mukhopadhaya added an answer in Nonlinear:
    How to solve system of three nonlinear equations?

    For example the three equations are 




    a1,a2,a3,b1,b2,b3,c1,c2,c3,d1,d2 and d3 are the constants and x,y and z are the variable, I want to find the solution of the above three equation, please help me?

    Sayan Mukhopadhaya

    I have attached them, in my previous answer.

  • Deepak Samuel Vijay Kumar added an answer in Bivalves:
    What is the name of this bivalve collected from south east coast of India?

    need identification

    + 1 more attachment

    Deepak Samuel Vijay Kumar

    It is a cardiid....I agree with Thomas..

    Maoricardium pseudolatum Voskuil & Onverwagt, 1991 is one possibility or Maoricardium setosum (Redfield, 1846)  -- Indo-Pacific 



  • Asanigari saleem bhasha added an answer in Ranking:
    Comparative Marker Selection result from GenePattern: How to interprete?


    just now by
    pathreskoo • 0
    Using the same dataset, GSE49997, the comparative marker selection result from GenePattern is different from the result of pubmed GEO2R. Anyone have this experience?

    Besides, when I use filter to select those with fold change >= 1, the RANK is not at the top. In this case, which one should I selected? those with high fold change or those at the top Rank? Besides, those selected upregulated markers are group in one class, none of them are from the other class, is this normal?

    Asanigari saleem bhasha

    In comparative marker selection genes are ranked by fold change and T-test. Those have highest fold change and largest significant difference listed as 1, and as follows. If the markers are not showing in either group, take it as nonsignificant genes.

  • Manojit De added an answer in Spinel Ferrite:
    How do I calculate the bond length from FTIR spectrum?

    In all spinel ferrites (MFe2O4), two main broad metal oxygen bands are seen in the FTIR spectra. From there we can calculate force constant for both sites (Octahedral and tetrahedral). By knowing these how I can calculate the bond length (Fe-O or M-O)?

    Manojit De

    Ok...no problem...Dr. Thomas Mayerhöfer . Thanks for your opinion...

  • Sonali Kar added an answer in Epidemiologic Studies:
    What is the meaning of Odds ratio and Risk ratio and how can use them in epidemiological studies?

    I want to know the meaning of Odds ratio and Risk ratio and how can I use them in a case study or epidemiological studies of infectious diseases and how can I interpret its results?

    Sonali Kar

    yes very good interpretations.

    One more point to specify is odds is used over a sample statistics, ie when we donot know or are perhalps not knowing the baseline population. Odds have also popularized because of ease of calculation like in regression and in chi sqaure , the point of significance is often judged from odds, which is a ratio.

    Risk is an estimate when the baseline population is under consideration .RR calls for more complicated statistics.

  • Natthaporn Takpho added an answer in Protein Purification Techniques:
    Protein expression in E.coli, located in inclusion-body, how to purify without losing an enzymatic activity?

    I constructed a pET-53 to express yeast gene in E. coli BL21(DE3). The culture condition was culture the BL21(DE3) until OD600 = 0.4 

    Natthaporn Takpho

    Thank you everyone. How's about co-transfrom these two subunit together in the same cell and expecting that they will reconsitution themselves and I can measure the enzym activity from the inclusion-bodies. Notably that I have tried LB+1% glucose and M9 with several IPTG concentration but it still form an inclusion-bodies. 

  • Md Thoufic Anam Azad added an answer in Mycology:
    Cotton small RNA extraction?

    Recently I am extracting cotton root small RNA.  I need extract total RNA and use the commercial kit to enrich the small RNA. However, I found the RNA I extracted is poor quality and lower concentration, which cannot enrich large amounts of sRNA. Do you have good ideas for extracting good-quality RNA from cotton root? 

    Md Thoufic Anam Azad

    Tissue homogenization in presence of liquid  nitrogen than 

    Extraction by Plant mini kit for RNA extraction,  Quiagen 

    hope this will give good yield 

  • Rehana Bibi asked a question in Spectra:
    Hi can any one help me in explaining the mechanism of MB Dye adsorbed on NH2-MIL-125 MOF through FTIR Spectra?

    here i have uploaded my FTIR Spectra before and after experiment, i cant clearly understand the role of -NH2 and -OH group in this reaction.

    + 1 more attachment

  • MURTHY Sree Ramchandra Peela added an answer in Streptococcus Pneumoniae:
    High Cp values in qPCR?

    I am working on detection of Streptococcus pneumoniae in clinical samples like blood and CSF. I have been doing the assay based on the primers and probe recommended by CDC. However I reduced the reaction volume to 10uL instead of 25 uL, and increased DNA template to 2uL/10uL reaction volume instead of 2.5uL/25uL reaction volume. Initial run with a known positive had Cp value 23 and the NT (no template) had no amplification whatsoever.

    After my second run, the NT samples started to give Cp 35.00 along with some of my samples. The article I used as a reference says Ct > 40 should be considered as negative. I have also attached the article for the reference.

    Trying to find out a possible explanation, I searched in Researchgate, where some pointed out that Ct 31 - 32 should not be considered. 

    So I am unable to understand where to begin with. Kindly tell me how to troubleshoot this issue.


    + 1 more attachment

    MURTHY Sree Ramchandra Peela

    Thank you Murali

  • Heba Huessin added an answer in Protein Quantification:
    Can we do protein quantification using BCA/Bradford without repeating standard protein curve?

    i did BCA many times and standard protein absorbance very similar. Eg: 60 ug gives about 30 absorbance and 40 2.3 and same for the whole curve. It won't change as I use same concentrations . Can I just test absorbance of my sample and get their concentration by equation of previous curve?. 

    Heba Huessin

    Good suggestion. Thanks. 

  • Sheikh Nizamuddin added an answer in Autism:
    Is there any non-invasive diagnostic tool for Autism and Epilepsy other than EEG?

    Is there any non-invasive diagnostic tool for Autism and Epilepsy other than EEG?

    Sheikh Nizamuddin

    @Adham Atyabi - Sir we do not have eye tracking system or machinery available here.

  • Anoop Kumar Srivastava added an answer in Soil:
    What do you mean by climate smart soil fertility management ?

    Climate change is a global phenomenon , and is taking place ever since , earth came into existence . There are well marked cold and hot cycles in the history of earths climate. However , these changes have been observed more rapid in the last 100 years or so. Looking at the definition of soil,  climate is the most pre-dominant  factor  responsible for changes in  developmental process of soil . Resultantly , soil physico-chemical as well as biological properties are the consequential changes of climate change. Such changes offer much bigger challenge for better soil fertility management vis-a-vis sustained crop production . In this background , i propose following questions to our learned colleagues to please throw some lights , so that the subject could be better understood with regard to soil fertility management : 

    *What are the components , shall we consider while dealing with climate smart soil fertility management ?

    *Which nutrients are more vulnerable to climate change related issues?

    *Do you feel, we need to devise  newer strategies of soil test -based fertilizer recommendation?

    *Do you feel, we need to revisit our long pending crop-based recommended doses of fertilizers ( RDF).

    *How shall we address the changing dynamics of nutrients in relation to climate change?

    *How shall we bring periodical changes in land use in view of climate change  related issues?

    * What is the ultimate strategy of soil fertility management vis-a-vis climate change ?

    Thanks and Regards 

    Anoop Kumar Srivastava

    Dr Reddy , i do agree with your candid statement , climate  chnage will continue to act as a  irreversible change , as long as we are not preamptive in our efforts  to consequential changes taking place in response to climate change . Unfortunately , impact of climate change becomes visible only at advance stage , especially when we talk of agriculture , until then agriculture  practitioners keep guessing one or the other reasons...Soil erosion is undoubtedly one of the most valid reason of climate change , having cascading effects on variety of other environmental services as part of terrestrial system...

    Thanks  Abhishek and Hussain for  adding your responses and appreciating the discussion . Predicting crop  yield based on changes in soil fertility in response to climate change is infact,  very much desired but again precision of prediction is largely dependent upon the filed verification and consequent model refinement to tune the prediction fro other extrapolative regions...

  • Yihua Hu added an answer in Hall Effect:
    What is caused the spikes when I am using the Hall Effect transducers, LA25-NP?

    Currently, I have a problem about the current measurement.

    I used the Hall Effect transducers, LV25-P and LA25-NP, to measure the input voltage and input current for the Buck-Boost. The details of the Buck-Boost can be seen in the first figure. The current signal is measured by the LA25-NP and sent to the signal condition circuit as shown in the second figure. 

    I used the PV emulator, Chroma ATE-62050H-600S, as the input source for the Buck-Boost. Some results are shown in the third figure, where the explanation of the channel 1-3by oscilloscope can be seen in the second figure.

    Now, my questions are:

    1. What is the spikes as I marked with red circle?
    2. How to eliminate these spikes?

    + 2 more attachments

    Yihua Hu

    It will be much better if the current reaches the rated current of LA25P. Usually, I make more windings for LA25P to reach the rated current of sensor. The twisted wire also can mitigate the signal noise.

  • Muhammad Hassan Agheem asked a question in Color:
    Why do the iron oxide (as a mineral) not detected through XRD?

    There are some reddish/pinkish coloured sandstones; where megascopically it appears that they have significant amount of iron oxide as their color indicates. When these samples were analyzed on EDS which shows significant peak of Fe along with Si, C, O and Ca. The thin section study also show its presence while there is no any peak of any iron bearing mineral in XRD pattern. Can any one tell me the reason?

  • H. S. Suresh added an answer in Teak:
    How to identify natural populations (original / relic) of teak in India?

    Teak is one of the most "mobile" species, moved rampantly by humans in the last 300 years. Natural populations have been "corrupted" due to such unscrupulous movement of propagules. Hence what criteria could be considered to identify the "relic" natural populations of teak in India?

    H. S. Suresh

    Hi Vasu,

    I think better question to be asked about teak in south India would be when did the teak was naturalized? I dont think we had natural population of teak. All that we know about teak is planted and later naturalized.  We need to get into genetic markers that can be identified and can dated to have broken away from its natural population probably in Burma (mYanmar).



  • Paolo C. Colet added an answer in Health Care Services:
    Are there any tool/scale/questionnaire regarding "access to mental health care services" ?

    I would like to determine the disparity in access to mental health care services.

    Paolo C. Colet

    Thank you Noura and Abdulqadir.

  • Ossama Mohamed Zakaria added an answer in Lung Cancer:
    What is the size of the lung metastases that need metastatectomy?

    What is the size of the lung metastases that need metastatectomy? 

    Ossama Mohamed Zakaria

    Thirty to 40% of all extrathoracic cancers lead to secondary pulmonary lesions during the course of the disease, and approximately 20% of these cases feature metastases that are confined to the lungs.

     Nevertheless, over 20% of patients with solid tumors, including colorectal adenocarcinoma, may have metastases exclusively in the pulmonary parenchyma, with no detectable involvement of other organs. In these patients, surgical resection of lung metastases may significantly impact long-term survival. Pulmonary metastasectomy is currently indicated for patients with the following criteria: primary tumor controlled; no evidence of metastases outside lung parenchyma; possibility of complete resection as verified by chest imaging; pulmonary function compatible with the proposed lung resection procedure; and lack of another available treatment that would be more effective than metastasectomy.

    The most important factor here is not only the size but the frequency and bilaterality of the metastatic pulmonary nodules.

    In the case of bilateral nodules, a staged thoracotomy is to be performed starting on the side with the lowest likelihood of a complete resection. Several factors may  determine which side to start with, including the number of nodules identified by chest CT, the anatomical position of one or more nodules relative to the pulmonary hilum, and the potential need for a more complex and extensive lung resection.


    1- Younes RN, Haddad F, Ferreira F, Gross JL. Surgical removal of pulmonary metastasis: prospective study in 182 patients. Rev Assoc Med Bras. 1998;44:218–25.

    2-Martini N, McCormack PM. Evolution of the surgical management of pulmonary metastases. Chest Surg Clin N Am. 1998;8:13–27

    3-. Younes RN,   Gross JL, Taira AM,  Martins AAC,  NevesI GS
    Surgical Resection of Lung Metastases: Results from 529 Patients.Clinics (Sao Paulo). 2009 Jun; 64(6): 535–541.

  • Xianqian Zhang added an answer in Oscilloscope:
    The noise and bandwidth measurement of the transimpedance circuit?

    How to measure the noise of the transimpedance circuit by using the oscilloscope?shorting the interveting input terminal or opening it? And the bandwidth was measured by applying a sinusoidal signal with a resistor of several MΩ to the input,and then observe the attenuation of output voltage from the oscllloscope with the change of the sinusoidal signal frequency.This measurement way is right or wrong?

    Xianqian Zhang


    Firstly, I should explain that the circuit have been designed and the photo detector is the photomultiplier.

    The circuit design referred to the book "Photodiode amplifiers op amp solutions". It consists of two stage amplifications: the first stage has an op amp, a feedback resistor R1 and a feedback capacity C1; the second stage is a voltage amplifier. To meet the high gain requirement, the R1 used the metal film resistor of 100k. The C1 prevents the oscillation and reduces the noise, but it would be limit the bandwidth. The noise calculation learned from the book “Operational Amplifier Noise Techniques and Tips for Analyzing and Reducing Noise”. Can you explain the “superposition methods”? I want to learn these methods and use them.

    After calculation, I used the oscilloscope to measure the noise of the circuit, but I not sure if the input terminal should be short or open it. A professor told me that a 1G ohm should be as the input resistor in series because the extremely large resistor would be produce the extremely small current noise. And then when this small current noise flows the circuit, the total output noise approximately regard as the noise floor of the circuit.      

    Now I am using the spectrum analyzer to measure the noise, so I desire for some advices from you.

    Thank you very much!

  • Ronny Steen asked a question in Global Positioning System :
    Recommendations of GPS with UHF base station to monitor Ospreys?


    We wish to get recommendations on GPS to use (UHF local downloading at a base station close to nest) for Ospreys (Pandion haliaetus). We wish to track hunting activity during breeding and register air-to-water plunge diving. The fixes have to be frequent so we could get data on fish capture localities (e.g. 5 min). Including accelerometer and altitude data.

    Any suggestions? 

    Regards Ronny 

  • Andrew Stewart asked a question in Immunoassay:
    Does anyone have experience in coating 96 well microplates with stabilizers so that the plate can be dried, packed and shipped for ELISA test kits ?

    We are looking to develop a test that has antibodies which need to be stored in dried format on a 96 well plate.  The plates will be packed and stored then sent to other labs to perform ELISA immunoassays. There appears to be numerous commercial stabilizers available, and any insight into using these from a practical viewpoint would be appreciated.