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  • Ali Alhayany added an answer in Biofertilizers:
    Are there any research paper about the effect of bio fertilizers application on bud success of fruit trees?

    are there any research paper about the effect of biofertilizers application on bud success of fruit trees?

    Ali Alhayany


    I am using Azotobacter  chrococcum,Azospirillum  brasilense , and Pseudomonas  flourescence bacteria inoculated Apricot seeds with these types separately and in combination of the first one with the third one ,and the second one with the third .The experiment  started many months ago but i like to increase my information by requesting help from those whose specialist in the field of bio fertilizers to support my work  and i hope you would be the first one in this line.

    best regards


  • Nageswara Rao Posinasetti asked a question in Nanomanufacturing:
    Interested in contributing a chapter on a book on Nanotechnology applications in Mechanical Engineering?

    We are in the process of developing a book on Nanotechnology applications in Mechanical Engineering.

    As you are aware, nanotechnology has spread into all fields of engineering and technology. Though several books on nanotechnology are available, very few books deal from the perspective of a mechanical engineer. This has prompted our endeavour to bring out a book on Nanotechnology emphasizing on applications in mechanical engineering. Apple Academic Press will publish this book and CRC Press will distribute it worldwide. We are planning to get the contributions of chapters for the book from persons who have made their indelible mark in the respective fields. The length of the manuscript is to be between 25 and 40 pages. Some of the suggested topics to be covered in the book are:

    • Nanoparticles
    • Carbon nanotubes
    • Nanomanufacturing
    • Nanocomposites
    • Nanocoatings
    • Nanolubricants in IC engines
    • Nanocoated cutting tools
  • Venky Raavi added an answer in Lymphocytes:
    What is the total volume of buffy coat needed to obtain 1x10^8 lymphocytes?

    The kit I am using states that I need to start off with 1x10^8 of lymphocytes isolated from buffy coats. Does anyone know the total volume of buffy coat I should start off with in order to obtain this quantity of lymphocytes? Thanks!

    Venky Raavi

    Hi Oriana,

    You can use Ficoll-histopaque-1077 for better isolation of lymphocytes, After isolation dissolve the cell pellet in few microliters (50 to 100) of PBS or RPMI medium and count the number of cells using cell counting chamber. based on the cell count u can dissolve the pellet as you required. Generally, 1-2 ml will give sufficient number of cells.

  • Veronika Samotskaya added an answer in Acoustic Analysis:
    Does anybody have song recordings of African Reed Warblers (Acrocephalus baeticatus)?

    I am searching for good song recordings of African Reed Warblers. The longer the better. Or maybe somebody works near the habitat of these birds and it's not a big deal to record several minutes for me :)

    There are some recordings on xeno-canto.org, but they are way too short for the analysis :(

    Veronika Samotskaya

    Pavel, by the way, remember to write me criteria of the recording you use so I can record you something during the next season. Also, as soon as I know, I can ask my collegues, most likely they have a lot of Yellowhammer :)

  • Andrii Gakhov added an answer in Politeness:
    What are the software programs that can be used for the analysis of texts?

    My research examines comparison of politeness strategies used by two groups of students.

    Andrii Gakhov

    Sometimes it's just easy to right a few lines of code instead of using tools/services ... I wonder why nobody mentioned yet the NLTK library (Python) and Stanford NLP (Java) that could help a lot.

    + 1 more attachment

  • Alphus Dan Wilson added an answer in Bacterial Cell Culture:
    Is it safe to discard in sewer bacterial culture after bleach inactivation?

    Dear all,

    In my lab we are using liters and liters of highly dense bacterial culture and the bacteria contains a vector carrying antibiotic resistance gene. Bacteria are harvested but a bit of culture always remains in the vessels and we usually inactivate bacteria with bleach and some hours after, we transfer it in sewer.

    Bacteria are certainly dead but can we consider that the bleach treatment inactivates the vector and its ability to provide antibiotic resistance?

    Same question with the antibiotic medium. Does it contain significant amount of antibiotic after on overnight culture ? If yes, we should not put it in the sewer, right?

    Thank you for your feedback!


    Alphus Dan Wilson

    It is always best to autoclave microbial cultures before they are discarded. We do not want any microbes or antibiotics being released into sewer systems where microbes may be selected for resistance to antibiotics upon exposure (very similar to antibiotic resistance being generated in humans that take antibiotics unnecessarily to prevent infections whenever they fell like they may be getting sick; some doctors still make this mistake of over-prescribing antibiotics for people who do not need them).

  • O. Boudebbouz added an answer in Inverters:
    How to design an LC filter without affecting load impedance?

    I am designing an LC filter for an inverter. If I design L and C values without load (RL) its fine, but after connecting load (RL) the effect of filter is changed. What should I do for having effect of load on filter values is less.

    O. Boudebbouz

    RL load acts as a damping element and alters the harmonic spectrum so that the peaks of any resonances move in the axis harmonic orders. I advise you to consult the work of Wouter RA Ryckaert, Jozef AL Ghijselen, Jan AA Melkebeek and Hartana.

  • Humaira Fatima added an answer in Amylopectin:
    Has anybody tried to use Megazyme Amylose/amylopectin to measure rice starch?

    My research group is trying to measure amylose by using megazyme kit but they are not getting the result. Has anybody used the kit for rice flour?

  • Susan C Hubchak added an answer in HUVEC:
    Why are HUVECs non-responsive to treatments?

    Hello everyone,

    So I am culturing HUVECs (purchased from Lonza) to estimate their activation responses to some growth factors. However, I notice no change in the output, such as cytokine production, or nitric oxide levels. Previously published reports suggest that there is an upregulating effect of these treatments.  

    I used cells between passage 2-4, and seeded in low-serum medium (EBM2 + 0.5% FBS) supplemented with hydrocortisone and ascorbic acid,  and incubated for upto 18 hours (starvation) before adding my treatments. 

    Please help me track the problem, or suggest an appropriate scheme, as I consulted many papers to follow the method but the problem seems to persist in my case. 

    Thank you very much!

    Susan C Hubchak

    Manindra, perhaps the HUVEC would be responsive if slightly less crowded?  Sometimes cells are not responsive to GF when too confluent.  Maybe repeat, using 40-60K per well with 80-100K as "negative" control.  You could also try pre-coating well with gelatin, collagen I or fibronectin to see if it makes a difference.  Also, talk with Lonza tech services for suggestions.

  • Alberto Ortiz-Vigón added an answer in Periodontics:
    When using bio-active materials in periodontal regenerative procedures, like EMD or PRP, what prevents cellular irregular proliferations ?

    what inhibits a state of over- stimulation of a certain cellular type, is it just the saturation of the limited number of the cellular receptors?

    Alberto Ortiz-Vigón

    The role of regenerative periodontal therapy is the reconstitution of lost periodontal structures, with new formation of root cementum, periodontal ligament, and alveolar bone. Research has pointed to the important role of enamel matrix protein derivative (EMD) in periodontal wound healing. The enamel matrix is generally believed to regulate the initiation, propagation, termination, and maturation of hydroxyapatite crystallites in enamel. The enamel matrix also has a function outside the developing enamel. Enamel matrix proteins are temporarily deposited onto the dentinal root surface and provide an initial and essential step in the formation of a cellular cementum. Autoradiographic and scanning electron microscopy studies provide additional evidence that the cementogenesis process is initiated and kept modulated by these proteins following apoptosis of Hertwig’s epithelial root sheath cells and deposition of enamel matrix protein onto the dentin surface. 

    Best regards

  • Harry Back asked a question in Irritants:
    Could a posture chair (sitting at an angle of around 20degrees to open the hips and straighten the spine) directly improve condition?

    Moreover, not necessarily improve the condition but stop irritation and aggravation and thus improve the patients wellbeing and enabling recovery and strengthening of the supporting muscles. 

  • Aashiq H Kachroo added an answer in DNA Fragmentation:
    Could you take a look at those DNA fragmentation assay results?

    The image shows DNA fragmentation assay of cells treated with toxin. I'm not sure how to read those results. For sure there is fragmentation in well with number 1, but what about wells 2 and 3? Does anyone know what this smear could mean?

    Aashiq H Kachroo

    Where is your control?

  • Morteza Feizi added an answer in Simulators:
    Has anyone ever applied MINTEQ program to model metal release from solid phases?

    Has anyone ever applied MINTEQ program to model metal release from solid phases? How do I simulate solid phases in the program? Would you please tell me your experiences?


    Morteza Feizi

    Thanks a lot Dear Santos

  • Agostino Prástaro added an answer in Foundations of Quantum Mechanics:
    How do we understand a conservation law (Noether's theorem) in quantum mechanics?

    In the classical mechanics Noether's theorem says that

    "if a system has a continuous symmetry property, then there are corresponding quantities whose values are conserved in time"

    As a simple particular case, a quantity A that doesn't depend on time explicitly, neither through other parameters on which it depends, i.e. dA/dt = 0, is a constant of motion.

    The question is what becomes of this law in quantum mechanics (QM)? Does it hold at all? And if it does, what is its meaning?

    The QM gives the following formula for the time derivative of an operator Ȃ:

    (1) dȂ/dt = ∂Ȃ/∂t + i/ħ (ĤȂ - ȂĤ),

    where Ĥ is the Hamiltonian of the system, and Ȃ is a Hermitic operator attached to an observable of the system.

    Assume now that Ȃ doesn't depend explicitly on time and commutes with Ĥ, therefore dȂ/dt = 0. How shall we understand this result? Does it mean that the value of the operator Ȃ is fixed during the system evolution, even if we don't measure it?

    Or, alternatively, does it mean that performing a measurement of Ȃ on identically prepared systems, we are bound to find the same value of Ȃ?

    In other words, in the QM, a quantity which is a constant of motion, possesses a value, and it is fixed in time, independently on whether we measure it or not? Or, alternatively, it takes a value only if we measure it, and the value is the same if we repeat the measurement on identically prepared systems?

    Agostino Prástaro

    Dear Charles,
    what you claim is completely wrong !

    'Geometry is a mathematical idealisation, which was fine as an approximation for classical science as was carried out in the nineteenth century, but we now have 90 years of quantum theory, in which it has long since failed in steps (b) and (c).'

    Any mathematical formulation is an idealization ! ... Also your naive 'POSTULATEs' in your paper are idealizations ...

    The last 90 years of quantum theory are full of great successes !!! ...

    Only a stupid man can spit on the wonderfull results of the quantum physics in these last decades !  Of course nothing is perfect, the science works step by step with larger generalizations, by an inclusive method of previous knowledges.

    Sorry but your claims are really a nonsense !
    At this point I cannot continue to discuss with you more!

  • Alphus Dan Wilson added an answer in Fungal Biotechnology:
    How long can a sample for mycology (infected plant) prior to screening be stored under 4 degree Celsius?

    I took sample from infected stem of tropical tree in the forest. I read from some sources that screening should be done as soon as possible to get accurate result. It is optional to store sample under 4 degree but the duration limit of fungi viability or potential of contamination is not stated.Is there any other way to lengthen the viability of fungi in the infected sampel?

    Alphus Dan Wilson

    The longer you wait after sample collection prior to isolation attempts, the longer the probability that contaminants will overgrow and colonize the tissue you are isolating pathogens from (often precluding effective isolation) although placing the samples in dry conditions (low humidity) in paper bags (not plastic) at 1-4 C will reduce contamination for a short time (< 1 week).  Place the infected in a high-humidity environment only if you want to induce sporulation of the pathogen on the tissue sample for spore isolations. 

  • Syed Abbas Jafar added an answer in Climate Change:
    Are there authentic published work confidently pinpointing the sole anthropogenic factors contributing to Climate Change?

    Combined natural and anthropogenic factors (geologically recent phenomenon) govern Climate Change. It is, therefore, of paramount importance to discretely recognize the role of humans in Climate Change and to plan efficient strategy to mitigate it.

    Syed Abbas Jafar


    Would you kindly point out where the wrong wording is? Moreover, I quoted about illusion of Knowledge not Science. Please be outright crisp in your comments and do not deviate from the real substance of the Question asked.


    Thanks for your understanding. Would you kindly provide a link which can prove that the mention of the year 2035 was a typographical error. In fact even before the report was published, some experts had already warned in 2006 not to go ahead with publication, but Alarmists went ahead with publication. This was an epic and possibly deliberate blunder and not a typing error! This was widely covered by media (See Cogley et al. (2010): Tracking the Source of Glacier Misinformation (2010): Science, 327(5965): 522. Himalayan glaciers are in good shape and stable (see Bahuguna et al. (2014): Are Himalayan glaciers retreating? Curr. Sci., 106(7), 1008-1013. When you are not so busy give it a cool and serene thought instead of hurriedly giving twisted facts. Best.


  • Jorge Castañeda asked a question in Sulfur Acids:
    After using coverslips treated with APTS as substrate for organic tissue, can I reuse the coverslips after bathing them in sulfuric acid overnight?

    I use coverslips treated with APTS as a substrate for tissue. Can I reuse the coverslips (treat them again with APTS) after I bathe them in sulfuric acid overnight?

  • Aamir Raoof Memon added an answer in Muscle:
    Oes anyone knows a definition of Core Muscles?

    I Found many studies about core training but i cannot find any definition of it. 

    Aamir Raoof Memon

    Dear Raul a few resources to help you may be as follows:

    In an article Core Stability Exercise Principles, they define it as "The so-called core is the group of trunk muscles that surround the spine and abdominal viscera"


    In "Muscles of the core", they define it as "The major muscles that move, support and stabilize your spine are called the muscles of the core or trunk"


    In "The myth of core stability", they say "In essence the passive human spine is an unstable structure and therefore further stabilisation is provided by the activity of the trunk muscles. These muscles are often referred to in the CS approach as the ‘‘core’’ muscles, assuming that there is a distinct group, with an anatomical and functional characteristics specifically designed to provide for the stability"


    In "Core Training: Evidence Translating to Better Performance and Injury Prevention" they say "These muscles act to stiffen the torso and function primarily to prevent motion. This is a fundamentally different function from those muscles of the limbs, which create motion. By stiffening the torso, power generated at the hips is transmitted more effectively by the core"


    I think it would suffice. Best of luck!


  • Johannes Kiefer added an answer in Sauter Mean Diameter:
    How are Sauter mean diameter of gasoline injectors measured ?

    How Sauter mean diameter of gasoline injectors are measured ?

    Johannes Kiefer

    there has been a recent overview article on spray diagnostics: http://dx.doi.org/10.1088/0957-0233/26/1/012002

  • Adolfo Quesada-Román asked a question in Geomorphometry:
    Do you know where can I get this book online?

    Anyone who knows where can I get the following book: Geomorphometry: Concepts, Software, Applications Edited by Tomislav Hengl and Hannes I. Reuter (2009).

    Thank you

  • Kenneth M Towe added an answer in Geophysics:
    What is the cause of this warming?

    In Sept. 2015, Ukrainian Central Geophysical Observatory  fixed just three temperature records in Kyiv.

    1)            Maximum temperature+35,7°C  was in Sept. 2.  This day was the warmest September since 1881.

    2)            Also on this day on 6,5°C was exceeded and pre-historical significance of the average daily temperature, which was fixed in 1938. The average temperature reached +29.1°C.

    3)            In addition, 3 September in Kiev was fixed very warm night of 1881 to that date. Night temperature is not dropped below + 20,6 ° C and thus on exceeding 3,1°C prior to the historical significance of this day in 1899.

    P.S. Most water wells disappeared. This has not been a long time !!!

  • Frederik Schenk added an answer in Climate Variability:
    Where can I get climate variables for the Younger Dryas period (circa 14.000 years BP)?

    In my study I am trying to verify whether there have been climate refugia for a species. Unfortunately, publicly available databases only have data for the Last Glacial Maximum (circa 21kya), the Holocene (circa 6kya) present and future. Considering that the Younger Dryas were a period of forest (vegetation) contraction and this could influence the distribution of my targeted species, I think it would be important to include it in my study. Unfortunately, I can't find climate variables for this period. Can anyone provide any suggestion?

    Thanks in advance!

    Frederik Schenk


    yes thx I saw some warm summer papers now but I cannot just take them because they agree with my model and dump the rest into the septic tank ;-)

    The question remains what is reflected by different proxies (in terms of variable space) when not taking so far results for granted. Are the empirical or physical transfer functions multi-variate, are they stationary?

  • Wahiba Abu-Ras added an answer in Arabic Language:
    Are there validated Arabic versions of the Hospital Anxiety scale and the CES-D Scale?

    I am interested in finding two important scales that have been validated and translated into the Arabic Language. One of the scales called Hospital Anxiety and Depression Scale and the other one is related to depression (CES-D Scale).

    Wahiba Abu-Ras

    Dear Dr. Ibrahim,

    So nice to hear back from you.

    I truly appreciate your help.

    I got all the articles but could not find the actual scale in the Arabic Language. I emailed Dr. Mona but she did not answer  me yet. Still looking for the religious coping scale with Arabs.

    Thanks again for all your help and support. Salamat,


  • Mikhail A Gavrilin added an answer in Gene Expression:
    What is the best formula between 2^dCt and 2^ddCt for analyzing the data from stress and non-stress condition?

    Dear, researchers

    I try to study the gene expression between stress and non-stress condition, for example, I treat the sample with H2O2 at 37C for 1 h (stress condition) while the normal condition I incubate the sample  at 37C for 1 h (same as stress condition). 

    What the best formula between 2^dCt and 2^ddCt for analyzing the data from stress and non-stress condition?

    Thank you all.

    Mikhail A Gavrilin


    all we need is to put the data to excel spreadsheet. We usually calculate dCt, ddCt and then RCN. So we have all desired information. Hovered, I prefer (my choice) to express the data as RCN (yes, arbitrary, relative to expression of housekeeping genes) because it not only tells me the direction and fold of gene regulation, but also starting and end values (yes, relative). All the values are very reproducible. If you (and Wiyada as well) want, I may send my excel spreadsheet by mail.

  • Dumitru Casian added an answer in Thrombophlebitis:
    What are the pros and cons for high ligation and stripping with phlebectomy for acute superficial vein thrombosis in patients with varicose veins?

    According to our experience there is not any significant difference in outcomes (rate of complications, rate of recurrence, level of patient satisfaction, QoL) between surgery for uncomplicated varicose veins and superficial thrombophlebitis. Moreover, this approach seems to be more cost-effective comparing with one month anticoagulation with LMWH or fondaparinux, followed by elective surgery or saphenous ablation.

    Dumitru Casian

    Thank you Dr. De Maeseneer for your answer! Your expert opinion is very important! I'm completely agree with your approach, because it is less invasive and with proven efficacy. Unfortunately, our patients usually prefer to be supposed to surgery because it is completely covered by medical insurance but medical treatment - is not. If surgery is performed during the first week of SVT, the stripping of GSV is technically not difficult and stab thrombectomy from tributaries results in fast decrease of inflammatory reaction.  

  • Alphus Dan Wilson added an answer in GRASS GIS:
    Is there any relation of VFA with CH4 production between C3 and C4 grasses?

    I am planing to work on CH4 production from C3 and C4 grasses

    Alphus Dan Wilson

    Here are some references that give information about your question:

    1) Macheboeuf et al. 2014 (see attached link)

    2) Jayanegara et al. 2013 (see attached link)

    The first reference found no relationship for some plants, but the second reference indicates that methane production can be estimated by VFA composition.

    + 1 more attachment

  • Joseph Benoun added an answer in S2 Cells:
    Using S2 cells for tetramer induction using CuSO4, protein yield has been low, is it possible the stock CuSO4 (more than 2 yrs old) has gone bad?

    Making tetramer using S2 cells

    Induction is with copper sulfate 

    Protein yield should be higher than what it currently is according to protocols and other lab members who have made it previously

    Using previously made stock CuSO4 that has been on the shelf for a while

    Determined that protein is not being lost in the wash steps of purification.

    Joseph Benoun

    The stock solution is easily 2+ years old. It had been used successfully before. 

    We have plenty of anhydrous available to make more, I was just thinking from a logistical standpoint if that could be the source of my problem. In my mind, it is a likely candidate for the low protein induction/recovery

  • Vit Jan asked a question in Electrolytes:
    Is it possible to deposit separately two metals from one common electrolyte by changing the depositing voltage?

    So a layered structure may be formed by alternating two potentials..