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  • Tm Chaudhry added an answer in Hyperaccumulation:
    Are there any heavy metal specific bacteria that enhance the uptake of that metal only in hyperaccumulators?

    I am working on bio-remediation (hyper accumulators+bacteria) of heavy metals and want to test bacterial strains that are only metal specific. i.e. one strain for each metal..

    Tm Chaudhry · Science Department, PSMCHS

    The rhizosphere microbial populations are known to affect heavy metal mobility and availability to the plant through the release of chelating agents, acidification, phosphate solubilization and redox changes, and therefore, have potential to enhance phytoremediation processes.
    The chelating agent like Ethylenediaminetetraacetate (EDTA), which successfully utilized to enhance phytoextraction of lead and other metals from contaminated soils. Phytochelators in making the heavy metals, bio-available to the plant and their symbionts in enhancing the uptake of bio-available heavy metals.
    The use of rhizosphere bacteria in combination with plants is expected to provide high efficiency for metal uptake from the soil. Rhizosphere microorganisms, which are closely associated with roots, have been termed plant growth promoting rhizobacteria. Research has also shown that many rhizobacteria are tolerant to heavy metals and play important roles in the mobilization or immobilization of heavy metals. In one of the study it is reported that the addition of Sphingomonas macrogoltabidus, Microbacterium arabinogalactanolyticum and Microbacterium liquefaciens to the plant Alyssum murale grown in serpentine soil significantly increased the plant uptake of Ni.
    Among soil microorganisms, mycorrhizal fungi are the only ones providing a direct link between soil and roots, and can therefore be of great importance in heavy metal availability to hyperaccumulators plants.
    Some references about rhizosphere soil microorganisms that enhance metal uptake in hyperaccumulators are as follows:
    1. Chaudhry TM and AG Khan (1998). Role of symbiotic micro-organisms in sustainable plant growth on heavy metal contaminated industrial sites. In: Microbial Technology for Sustainable Development and Productivity (Ed. Rajak, RC) Scientific Publishers, Jabalpur, 270-279.
    2. Khan AG, C Kuek, TM Chaudhry, CS Khoo, WJ Hayes (2000). Role of plants, mycorrhizae and phytochelators in heavy metal contaminated land remediation. Chemosphere 41 (1), 197-207.
    3. Li WC, ZH Ye, MH Wong (2007). Effects of bacteria on enhanced metal uptake of the Cd/Zn-hyperaccumulating plant, Sedum alfredii. Journal of Experimental Botany 58 (15/16), 4173–4182.
    4. Kuffner M, M Puschenreiter, G Wieshammer, M Gorfer, A Sessits (2008). Rhizosphere bacteria affect growth and metal uptake of heavy metal accumulating willows. Plant Soil 304, 35–44.
    5. Jing Yan-de, Zhen-li He, Xiao-e Yang (2007). Role of soil rhizobacteria in phytoremediation of heavy metal contaminated soils. J Zhejiang Univ Sci B. 8(3), 192–207.
    6. Weissenhorn I, C. Leyval, G. Belgy, J. Berthelin (1995). Arbuscular mycorrhizal contribution to heavy metal uptake by maize (Zea mays L.) in pot culture with contaminated soil. Mycorrhiza 5 (4), 245-251.

  • Mangesh Bawankar added an answer in Deconvolution:
    How can one quantify the secondary structure of protein by FTIR?

    I want to calculate secondary structure of the proteins by FTIR.

    To do so I recorded the Primary spectra of my protein. In order to get more resolution of the peaks I am doing deconvolution followed by curve fitting of the primary spectra. In doing so I have found the following problems. I am using OPUS software provide by Brooker.

    For deconvolution

    1. I do not understand how I can avoid over deconvolution of primary spectra. i.e. how to know the selected values for bandwidth and noise suppression factor are correct. Just by looking the spectra while deciding these values or is another statistical method is available which could tell the reliability of deconvoluted spectra?

    2. I have selected amide 1 region for the secondary structure determination. (1700 cm-1 to 1600cm-1). The baseline was corrected only within this region and proceeded for deconvolution. While performing deconvolution I observe that some of the region of spectra, ma be  from 1686 to 1670cm-1, were going to a more negative value than at 1700cm-1 which starts from zero. This is giving me problems while performing curve fitting.

    For Curve fitting.

    1. I determine the secondary derivative of my deconvoluted spectra and select the peak at particular wavenumber.

    2. in the opus software one needs to give another two parameter

    a. Intensity at particular wave number

    b. width

    I don't have a problem in selecting value for intensity, but which value should be put in the width column ?.

    3. After doing curve fitting it will give the value of RMS. I know the meaning of RMS, but how can I know what is the acceptable limit for this value. After every fit it will give the RMS value which is always different. I came to know from the literature that RMS value should be low. But how low?

    Thank You

    Mangesh Bawankar · Indian Institute of Technology Kanpur

    Dear All,

    Thanks for your valuable comments. I think, baseline correction from 1600-1700 cm-1, followed secondary derivative, peaks obtained in the secondary derivatives will be used for the curve fitting, value of half band width will be put in the width column followed by curve fit iterations, this procedure for the secondary structure quantification i have got after going through all of urs comments. My RMS value is coming in the range of 0.000093 by using this procedure.  Please comment if anything is not upto the mark in this procedure

  • What is the best method to analyse EBV?

    We have both paraffin- waxed tissue samples and blood from patients We would like to know what is the best method to use for the analysis of EBV?

    Marc-Antoine Perrenoud · University Hospital of Lausanne

    Real time PCR works well on both type of samples, with FRET, you just have to prepare the paraffine samples before extraction of DNA.

  • Kuang Le le asked a question in cDNA:
    How can I copy the cDNA of a large gene with 6Kb in size?

    this gene is so large that there may be many mutations wthin it,how to avoid this

  • To which extent can we consider language and speech to be different?

    Since language and speech are independent abilities, to which extent are they different? And what do they have in common?

    Dr. Mohammad Hamad Al-khresheh · Al-Isra University

    Dear Marie Di Pietro, your comments are highly appreciated.

  • Have we delayed in using colour pictures (medical illustrations) in Health Promotion amongst the local communities?

    I have wondered why many scientists, nurses and medical doctors do not use clinical (nursing and medical) colour pictures to teach or share experiences with the community members in this modern era of "Seeing is believing!"

    "AIDucation 20-10" is frankly the use of medical illustrations or colour pictures (Hospital library) for nurses and doctors; abused for the local village folks, schools, churches, mosques and workplaces to raise awareness.

  • How to know that carbon isotopic signatures in organic matter of sediments is pristine?

    pristine...that is original signature is not altered...

  • I'm looking for a linear system with feed-forward control system. Can anyone help me?

    Is there anyone who can introduce me to a linear system with feed-forward control system? Is it possible and applicable to control this system using remote control strategy?

    Hazim Hashim Tahir · MOST, Baghdad, Iraq

    Dear Mr. Amirian,

    you can find your answer in any Control Engineering book!! but I am attaching few articles here for you. I recommend to see the first three ones, please , they will help you a lot.

    Best Regards,

    Hazim Tahir

  • Christopher R. Lee added an answer in Acrylamide:
    How can I determine acrylamide in food using ELISA method?

    I want to determine the quantity of acrylamide in food using ELISA (Enzyme-Linked Immunosorbent Assay) method rather than using HPLC, GC/MS. Can anyone guide me in using ELISA method?

    Christopher R. Lee · Retired

    The molecule seems to small. Immunological methods are unlikely to be appropriate for compounds that will have some degree of chemical reactivity with evey protein (and nucleic acid) they come into contact with. That reactivity is why acrylamide is of (geno)toxicological interest. In this field, you can't make compromises with analytical specificity for reasons of ease of use, speed or expense.

  • Rc Ropp added an answer in Tellurium:
    What is mean by the mesh size of tellurium powder and does the reactivity is different according to the mesh size?

    Tellurium (400 mesh) is not getting dissolved in Top( Trioctyl phosphine), where as 200 mesh size Te is dissolving..After all Te is forming coordinate bond with TOP (  Outer 5p shell of Te can accept the unpaired electrons from TOP) and thereby dissolving ( forming a colorless solution). So why it shows different reactivity according the mesh size?

    Rc Ropp · Rutgers, The State University of New Jersey

    I think you have already obtained the proper answers you need. It depends upon the method used to make the tellurium metal. If grinding is used to make the powder, then the heat produced by grinding causes the surface of the particles to oxidize. Try heating both sets of particles and you will likely see a difference in the rate in which the particles dissolve in the TOP. Also, try washing the particles in cold acid (dilute phosphoric & then dry-?}. I expect that you will be able to obtain a solution much easier. - RC Ropp

  • What are the important points for the detection of phospho-Akt in western blot?

    I am trying to detect P-Akt in my samples but I generally observe non spesific binding. I am using cell signalling antibody (4058-dilution rate:1:5000). I have used 5 or 3% BSA for primary and secondary antibody incubation. Can anyone suggest me an established protocol or tricks that I should follow?   

    alessandra maria adelaide Chiotto · Università degli Studi di Torino


    I've done it for the first time this week. I used both serine and threonine P antibodies, with saturation in 5%BSA for around 45 minutes at 42 C, and a dilution of the Ab 1:1000 ON at 4c. GREAT SIGNALS! ;) I used cell singlaling as well.

  • Mukut Gohain added an answer in DMSO:
    How can I prevent reactant degradation?

    I'am trying a N-arylation with K2CO3 in DMSO. It seems to produce the desired product but one of my reactants seems to degrade. I have too many byproducts on my reaction mixture. Any idea to adress this problem?

    Mukut Gohain · Chemical Process Technologies Ltd., Pretoria, South Africa

    You can use both solvent DMF and DMA for N-arylation at  100oC  with K2CO3.

  • How should we interpret the wavefunction of the universe?

    In an old paper at IJTP, Wim B. Drees argues against Hawking-Hartle's interpretation that wavefunction of the universe implies the probability for the universe to appear from nothing. What do you think?

    Salvador Robles-Perez · Spanish National Research Council

    It does not mean to appear from nothing with the absolute meaning of "nothing", i.e. something to which we can adscribe no properties. In fact, the universe would appear (in that paper and in many others) from the Euclidean region of the superspace (the configuration space of all possible geometries and matter fields), but from a physical point of view the Euclidean region, with an imaginary time variable, is not physical in the sense that no matter or energy field could be measured or exist. In that sense, it can be understood as nothing (physical), but the mathematical framework may cover more than what is called "physical reality". It is not much different to what happend in general in quantum physics. The fact of whether the wave function of a particle( or a field or whatever) is something "real" or just a mathematical construct from which we can obtain physical (i.e. measurable) properties is a matter of heated discussions in phiosophy of physics. My view is that it is not of much importance if we actually know what we are exactly meaning by the words we use and the properties we can eventually meassure. In any case, the H-H proposal entails a possible (and mathematically more or less tractable) explanation for the origin of the universe, according to the currently known laws of physics, and in some sense, it opened the door to a new whole branch of cosmology and physics allowing to make further developments on the subject (which is one of the best things that a physical proposal can do).

    Of course, the question is far from being totally settled. Let me point out that the multiverse (the set of all possible universes, which need not to be located in any space-time structure), for instance, would change many of the preconceptions usually made regarding the birth of the universe. For instance, Gott and Li (see the link) propose that the universe may even be its own mother, and many other proposals can be envisaged within such a novel paradigm. Broadly speaking, we could pose two options: either the universe is created from some space-time structure, which just put the question further to the origin of that space-time structure, or the universe is created from another (non spatial and temporal) structure, where it does not make sense to ask for the origin of the universe, in the temporal sense, because time would be created with the universe itself.

  • How to get rid of soluble protein aggregates?

    My protein is DNA binding protein, with the DNA binding domain having a pI of 9.3, while a tail of about 18 acidic amino acids is attached on the C-term end, making effective pI 5.2. I can achieve about 95% purity. The protein is in Tris 30mM, NaCl 200mM and Glycerol 10%, but is still forming soluble aggregates. Can anyone please suggest something.

    Amandeep Singh · Indian Institute of Science

    @Adam Zlotnick.. thank u so much.. DLS gives a wide no of particles sizes.. pointing to random aggregation points.. protein is kept at 1M NaCl throughout the purification.. No help :-/

  • How to know that carbon isotopic signatures are pristine?

    pristine...that is original signature is not altered...

  • V. Fulcoli added an answer in Gravitation:
    Does a mass (assumed point-like m), that follows its geodesic, emit gravitational radiation?

    Does a mass (assumed point-like m), that follows its geodesic, emit gravitational radiation?

    V. Fulcoli · Sapienza University of Rome

    @Yurij V. Baryshev:

    Hi... I agree wU

    the question arises because I'd like to investigate the question a littlebit wider. I'll try to explain. We know that a great desire of physics is given by the attempt to unify all interactions, either from the point of view of geometrodynamics (and I think to KaluzaKlein) or from the point of view of field theory.
    "To Unify" is a concept that tends to place as a unique entity that was before identified as a many-multi interactive-action... but compared to what?
    When we attempt to unify ... what do we want to reach? Unifying forces or "consolidate" the information?
    so  my question then arises spontaneously when I think about the differences between electromagnetism and gravity.

    If it really there was a superstructure electro-gravitational, when should it occur? looking at the deep distinction between the two phenomena....

  • Is there a way to measure the separate RGB of multiple selection using Image J?

    I will be analyzing digital images through RGB measurements. For this, I will use Image J. I am not an expert with it so what I do is select an area (using the round selector) then measure the RGB.

    Since I will be selecting several areas around the image, it will be very time-saving if I can select multiple areas and measure the RGB of each selection.

    Can anyone help me with this? A special plugin or a different freeware? I appreciate all your comments and suggestions!.Thanks.

    Girish Mallya Udupi · University College Dublin

    I am not sure what exactly you mean by "measure the RGB" (I haven't used ImageJ much). I am assuming that you mean statistics like mean/min/max intensities, for all the 3 channels.

    Anyway, the fundamental requirement seems to be that you want to select multiple areas and measure statistics of each region separately. Try the following - 

    1) Open the ROI Manager, Analyze>Tools>ROI Manager. Check the "Show All" and "Labels" options in the ROI Manager window.

    2) You can now use your selection tool, select a region and add it to the ROI list by clicking the "Add" button (shortcut "t") in the ROI Manager window. Repeat for the next region and so on.

    3) Since you want statistics from the 3 channels separately, convert the image to a multi-channel stack by using Image>Color>Make CompositeYour image window will now contain the three channels which you can access using the bottom slider.

    4) Click on the "Measure" button in the ROI Manager window. This will measure the statistics of marked regions separately and display them in the Results window. This will be for the channel which is currently displayed in the image window. Slide to the next channel, and click on the "Measure" button again and so on.

    In the Results window, you might have to go to Results>Set Measurements and check the "Display Labels" option so that the results would be named appropriately (with the region name and the channel name). The labels will be blank for the measurements made before checking this option. Hence it might be a good idea to check this option after the first measurement (so that the Results window pops up), clear the results and then starting over so that you will have labels for all your measurements.

    Hope this helps!

  • Kasturi Bhattacharyya asked a question in Elements:
    How major element studies of shale is useful?

    major element geochemical studies...

  • Thanu Alagu asked a question in Tuberculin:
    What are the immunological actions of Tuberculin PPD?

    Does anyone have experience in using them as Ag in DC-T-cell culture?

  • Carmen Camilleri added an answer in Nursing:
    With Supernumerary status nursing students are not counted in the number of staff in the ward. What is your opinion?

    Staff sometimes may be unsure about the interpretation of Supernumerary - will it enhance students to form part of the multidisciplinary team?

    Carmen Camilleri · University of Malta

    Thanks to Mr. Hojat and Ms. Briazu for the information. I also thank Ms. Crittenden for the explanation regarding preceptorship.  It would be of interest knowing what the additional training program of a preceptor consists of.  Thank you.

  • Roberto Estrada asked a question in Density Estimation:
    Implementing a density estimator per body parts

    I need more information about the 7 formula used in the article Real-Time Human Pose Recognition in Parts from Single Depth Images by Jamie Shotton et. al. I don´t understand the elements bc (learned per-part bandwidth) from the 7 formula. I have already made the classification.

  • Waleed Khadr added an answer in MIC:

    Dear my colleagues

    can any one explain for me how can i prepare these concentration  1:10 and 1:100 and 1:3000  from macfarland standard solution to do  detect the growth of bacteria and the MIC.


    Waleed Khadr · South Valley University

    Thanks so much but i  did you mean  by stock solution of mcfarland solution which i prepared from the bacteria inoculum in phosphate saline or  bacterial suspension which i prepared from the  bacteria in saline solution, by adding 10 ul per 3ml as standard solution.

  • Alfredo Argiolas added an answer in Abaqus:
    How do you solve the system error code 1073741819 in Abaqus 6.13?

    Dear all,

    I got the following error in Abaqus, when I use a UMAT:

    The executable standard.exe aborted with system error code 1073741819. Please check the .dat, .msg, and .sta files for error messages if the files exist. If there are no error messages and you cannot resolve the problem, please run the command "abaqus job=support information=support" to report and save your system information. Use the same command to run Abaqus that you used when the problem occurred. Please contact your local Abaqus support office and send them the input file, the file support.log which you just created, the executable name, and the error code.

    Can somebody help me?

    Thanks in advance.

    Alfredo Argiolas · Scuola Superiore Sant'Anna


    Have a nice work!


  • Katarína Sebeková added an answer in Saliva:
    What is the best method to determine total antioxidant status/capacity in whole human saliva?

    Human saliva can be collected noninvasivelly and includes numerous molecules that could have a role as potential biomarkers for research studies. In your opinion what is the best method to determine total antioxidant status/capacity in whole human saliva? Has anyone tried a (suitable for saliva) assay kit ?

    Katarína Sebeková · Comenius University Medical Faculty in Bratislava

    Hi Ioannis,

    some methodological remarks:

    visible contamination with blood significantly affects the results of antioxidative markers analysis - samples should be excluded. other important issues:

    Saliva collection

    Tooth brushing, circadian rhytm, variability, oral antioxidants

    dental, periodontal status:

  • How trace element studies are helpful in study of shales?

    trace element geochemical studies...

  • Kasturi Bhattacharyya asked a question in Provenance:
    How to do provenance studies of shale rocks?

    source rock of the shales...originof sediments?

  • Ilja Schmelzer added an answer in Cosmology:
    Can the initial singularity be removed from cosmology models?

    In a rather old paper, Michael Heller argues that in certain cases it is possible to remove the initial singularity from cosmology models. He discusses b-boubdary and noncommutative geometry. So what do yo think?

    Ilja Schmelzer · Independent Researcher

    To explain the universe as we see it, with large scale inhomogeneities in the background radiation, one needs inflation, that means, a mechanism which gives a''(tau) > 0 in the early universe.  Such a mechanism can, in principle, also prevent the singularity. 

    If the mechanisms which are assumed to give inflation today are able to do this I don't know. For a theory of gravity which prevents the initial singularity see http://arxiv.org/abs/gr-qc/0205035

  • Bethanie Hayes asked a question in Poverty:
    Reseaching the link poverty to the compliance of TB treatment?


    treatment compliance


  • What is the mythological / scientific reason behind burning crackers on festival of lights (Deepavali)?

    'Deepavali' is the festival of lights and is a very popular festival celebrated not only by Hindus but also by people of other religions (including Sikhs, Jains and some Buddhists). Apart from celebrations in India, it is celebrated by Hindus and others across the world. This festival is celebrated by lighting lamps and by bursting firecrackers. The festival is celebrated to mark the return of Lord Rama to his capital and also to mark the killing of Narakasura by Lord Krishna. The festival is celebrated for three days with the second day celebrated as Lakshmi Pooja, when Lakshmi, Goddess of wealth, is worshipped. The festival is also known as 'Diwali'.

    Mohammad Firoz Khan · Jamia Millia Islamia

    I don't think there some mythological angle behind burning crackers, if Rama was really a historical character instead of a character in an epic. For, gunpowder has been brought in India by Moughals and firework in India dates back only to Mouhal period. Therefore, it had been adopted by Hindus as expression of pleasure to welcome.

  • Darya Vanichkina asked a question in Cerebellum:
    Neuronal transplantation from one brain region to another?

    Are there any studies that report on what happens when you transplant neurons from one brain region to another? For example, mouse primary corticals in to a hippocampus or cerebellum? 

    NB Not interested in ES/iPS derived neurons - curious specifically about things that are already bona fide neurons.