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  • Denis Havlik asked a question in Scaling:
    How does access time in key/value databases scale with a number of entries?

    Imagine a simple big-data issue: I have billions of entries, and need to access them according to a predefined key.

    In the use-case I have in mind, search is not important. What is important is that I can ask the DB "does this entry already exist" and receive "yes" or "no" answer really fast. And a number of entries is going to be enormous.

    I figured out that the key/value databases are optimized for exactly this type of use cases. However, when I search for the scaling behaviour of the underlying algorithm, I get a huge number of hits on scaling the NoSQL DBs by adding new computer nodes and nothing on scaling of access times with number of entries.

    At first I thought that the time should scale as O(log(n)), but apparently it's better than that - according to some obscure results it could even be O(1). Then again, I don't believe in O(1) scaling for billions of data. Something is bound to break, sooner or later.

  • Any suggestions on a quantitative method for enzymatic lysis of gram-negative bacteria?

    I am looking to differentiate isoenzymes on lysing gram-negative bacteria.

    Ravi Kant Upadhyay · Deen Dayal Upadhyaya Gorakhpur University

    Hen white-egg lysozyme is used to lyse gram-negative E. coli intact cells the highest lysis rate occurred at pH 8.9 in the system containing 0.03 M NaCl. Digestion of cell wall is achieved by the addition of lytic enzymes to a cell suspension. Enzymes are highly selective, gentle and most effective. Lysozyme is widely used to lyse bacterial cells. The enzyme hydrolyses α-1,4 glycosidic bond in the mucopeptide moiety of bacterial cell wall of gram positive bacteria. The final rupture of the cell often depends on the osmotic pressure of the suspending medium. In case of gram negative bacteria like Escherichia coli pretreatment with detergent such as Triton X-100 or addition
    of EDTA is necessary. EDTA is used to destabilize the outer membrane
    thereby making the peptidoglycan layer accessible to lysozyme.Yeast cell
    lysis requires a mixture of different enzymes such as glucanase, protease,
    mannanase or chitinase. Sequential disruption of microbial cells for selective
    product release involves the use of lytic enzymes based on the type of
    microbial cells and process conditions. Importnat materials required are 
    Overnight grown bacterial culture, Alkaline CuSO4 solution, Folin’s reagent,
    Lysis buffer containing Lysozyme. 

  • Sunita Minz asked a question in ELISA:
    Anyone can tell me that without having readymade kit for indirect elisa how we can do quantitative estimation ?

    Method to findout titer value?

  • Does steroid administration has a favourable outcome in dengue shock or thrombocytopenia?

    There are no evidence based therapies for dengue shock management except meticulous fluid management. Some anecdotal reports claim that it is beneficial. 

    Prof. Dr. Shahid H. Sheikh · NIDS Treatment & Research Center, Lahore, Pakistan

    Re: Nationwide Preparedness for Ebola and related Hemorrhagic Fever viruses – Calling attention to a novel biophysically-based, orthomolecular treatment that has demonstrated "Zero Mortality"


    I simply wanted to call to your attention to a potentially valuable medical treatment that you and your colleagues may not yet have considered,

    specifically, a biophysical and orthomolecular treatment strategy. Such a treatment strategy has already shown both efficacy and safety in a group of ca. 1300 patients with closely-related hemorrhagic fever virus, Dengue, all of whom recovered with treatment. Yes, that’s right! There were no deaths.

    The amazing published results of American-trained physician and scientist, Professor-Doctor Shahid Sheikh, were recently brought to my attention. Since then, Prof-Dr. Sheikh and I have dialogues at length on his study, on the topic of the current Ebola outbreak in West Africa, and on the recent Ebola infections.

    As a practicing physician in the great state of Texas, I wish to share Dr Sheikh’s extraordinary Dengue fever results with you. These results support a professional opinion I have had for several years now: a biophysical/orthomolecular treatment paradigm will be required to fight this pathogen on its own terms, because the Ebola pathogen has evolved to utilize biophysical, supramolecular means of infection, multiplication, and spread.While the orthomolecular and orthodox (allopathic) strategies are not mutually exclusive, it may reasonably be argued that placement of ALL our hopes for a cure solely on the classical “vaccine” concept, is optimistic at best and fraught with considerable peril in terms of safety.

    An innovative new paradigm is urgently called for. I have presented the scientific basis for my opinion in several recent peer-reviewed scientific publications, which I can provide you upon request.

    Prof-Dr Sheikh and I hope to offer our special expertise and the fruit of our research in support of the nationwide effort, here in Texas, and throughout the U.S., and other countries that would be interested in partaking of the prompt development and application of a new biophysically-based, orthomolecular

    strategy, in more rational defiance of such infectious diseases. Such measures will strengthen our natural immune defenses against these insidious opportunistic neuroinvasive viral pathogens.

    Strategically, our approach has logical and logistical advantages over orthodox conventional strategies which may win a battle with, for example, a costly monoclonal antibody (MoAb), yet ultimately loses the war, in terms of concomitant serum sickness and microvascular ischemic events (infarctions). With proper financial support, the global burden in morbidity and mortality from the Neuroinvasive Hemorrhagic Fever viruses, need not progress unchecked, while waiting for an allopathic (vaccine) remedy which might not work.

    Prof-Dr Sheikh and I are presently seeking financial support and/or sponsors to support further development of our joint preclinical and clinical research and treatment protocols. These protocols are without doubt, at the very forefront (cutting-edge) of the current state of medical and scientific knowledge, globally.

    We are both of the opinion that a non-profit, multinational, global, multidisciplinary effort will be called for, to overcome this particular and similar infectious diseases. There will be spin-off benefit to humanity of knowledge gained for several other medical specialties, including hematology, cardiology, neurology, and oncology. Please feel free to contact us at your earliest convenience, should you wish to help your nation more readily defend against this milestone of a challenge that is threatening the public health.


    Robert M. Davidson, MD, PhD

    PO Box 1785, Kilgore, Texas 75663-1785

    903-235-0731 (mobile); email: patrons99@yahoo.com

    Affiliation: Internal medicine physician, PhyNet, Inc., Longview, Texas

    Prof. Dr. Shahid Sheikh, MBBS, PhD

    92-300-481-6677 (Cell)

    Chief Neuro Virologist

    Chairman, NIDS (Neuro Immune Dysfunction Syndrome) Treatment and Research Center

    Lahore, Pakistan

    References (3):

    (1) Breakthrough Treatment of “Dengue Viral Infection” The Report on the Dengue Viral Epidemic of 2011 in Province of Punjab Pakistan. Prof. Dr. Shahid Hussain Sheikh, IOSR Journal of Dental and Medical Sciences (IOSR-JDMS), Volume 5, Issue 3 (Mar. - Apr. 2013), PP 23-26



    (2) Davidson, R.M.; Seneff, S. The Initial Common Pathway of Inflammation, Disease, and Sudden Death. Entropy 2012, 14, 1399-1442.


    (3) Davidson, R.M.; Lauritzen, A.; Seneff, S. Biological Water Dynamics and Entropy:

    A. Biophysical Origin of Cancer and Other Diseases. Entropy 2013, 15, 3822-3876.


  • What are methods of measuring of dihydropteridine reductase (dhpr)?

    In 1975, dihydropteridine reductase (DHPR) deficiency was first recognized as a cause of tetrahydrobiopterin (BH4) deficiency, leading to hyperphenylalaninemia (HPA) and impaired biogenic amine deficiency. So far, more than 150 patients scattered worldwide have been reported and major progresses have been made in the understanding of physiopathology, screening, diagnosis, treatment, and molecular genetics of this inherited disease. Present knowledge on different aspects of DHPR deficiency, largely derived from authors’ personal experience, is traced in this article. 2003 Wiley Periodicals, Inc. Med Res Rev, 24 No. 2, 127–150, 2004

  • Is it required to know Argentinian Culture and Latinoamerican Theology to understand Pope Francis teaching and ministry?

    Perhapts Pope Francis could be enough understood as a sensible Jesuit in dialogue with up-to-date global social, economical, political and cultural happenings...

  • What's the interpretation of single photon interference in a double slit experiment?

    I want to know what are the reasons of this interference.

    How does quantum mechanics look for this interference? Does the photon interfere with itself or are the waves accompanied with it interfering with each other?

    What's the relation of wave particle duality with this experiment?

    What are the most acceptable interpretations of this experiment?

    Charles Francis · Jesus College, Cambridge

    I don't have to cite examples. There are too many of them, in both this and other threads. Any post in which you mention time dilation, simultaneity, voodoo, or any post in which you claim to criticise what anyone else has said.

  • What is a viable method of calculation of antiviral activity in vitro?

    Dear colleagues,

    I address to the experts on how to calculate the antiviral activity of compounds in vitro. I always thought that the medium effective conc. of a compound (EC50) – it’s the conc. which diminishes twice infectious virus titer (we are dealing with influenza virus). For instance: if in virus control lgTCID50=6, EC50 corresponds to lgTCID50=3 (drop on 50 %). But one colleague of mine affirms that conc. of viral particles drops twice with lgTCID50 drop on 0,3 (his logic is that log102≈0,3). Besides that it’s unrealistic to catch such subtle drop of infectious titer, a great part of inactive substances or having very poor antiviral activity would turn active and having a good SI (SI=CTD50/EC50). On your opinion, is that way of reasoning valid?

    Jarad Schiffer · Centers for Disease Control and Prevention

    I think the person suggesting the 0.3 factor is confusing IC50 with the midpoint parameter of a 4PL curve fit using log scale transforms. IC50 has a specific meaning - it means 50% reduction (as you are calculating it). Even if you are using log-transformed data to calculate IC50's, you should calculate the IC50 as where the curve crosses 50%, not where it crosses the middle of the log-scale curve (which is at about 30%). That makes it different and no longer comparable to IC50's calculated the standard way.

  • Does anybody has an experimental results/paper on surface integrity in micro drilling of Ti6Al4V?

    Hi everone,

    In literature there is no adaquate information about micro driling of Ti6Al4V alloy. Some authors observed strain hardening at drilled surface in convesional drilling. But we observed strain softening. Do you have any idea about this?, if yes can you share with me


    Kubilay Aslantas · Afyon Kocatepe University

    Thank you Ali Ibrahim

  • Mohammad Khosroshahi added an answer in Sand Dunes:
    How do we determine the source of dust storms in the area?

    Although determining the origin of sand storms on the Earth as well as possible, But it is difficult for dust storms.  Because this storm covers a large surface area and the specific days, and also dust storms do not always originate from sand dunes.

    Mohammad Khosroshahi · Research Institute of Forests and Rangelands

    Dear Pedro Correia: thanks a lot for your cooperation about my question.

  • Danish Jasnaik added an answer in Docking Software:
    Does anyone know about good RNA:DNA docking software, that can calculate the binding energy as well?

    I want to calculate the affinity of RNA with DNA strand, will calculating the binding energy and docking be a good idea? Is there a software developed to perform the same. Other than NXSensor, are there other sites than can give details about DNA accessibility? How important is this consideration?

    Danish Jasnaik · Padmashree Dr. D.Y. Patil University




    Hope this helps


  • Why does nanoparticle absorbance intensity increase after being treated by protein?

    I treated the silver nanoparticle with acetylcholinestrase. data showed after 3 hours the maximum absorbance peak for nanoparticle-protein increased than blank one. in blank sample there is just nanoparticle. 

    seyed mohammad motevalli · Shahid Beheshti University

    thank you Adam. have you any reference? i need to prove this topic.

  • Ioannis Paraskevopoulos added an answer in Games:
    Is anyone aware of resources for programming for game input hardware, covering recent advances in game sensors?

    For example, a book that would have sections on developing games using IMUs (eg wiimote), IR cameras (eg Kinect), gamepads etc as input? 

    Any kind of resource would be appreciated.


    Ioannis Paraskevopoulos · Anglia Ruskin University

    Thanks you all for your answers,

    I think the closest to what I'm looking for is Tangible User Interfaces suggested by Johann.

    Many thanks for this, I have identified a couple of books on TUI that might fit my purpose.

  • T.H. Been added an answer in Nematodes:
    Is anyone familiar with nematode exclusion in forest litter?

    What substance can I use to exclude the free living nematode in forest litter with least disturbance? Please recommend me some references.

    T.H. Been · Wageningen University

    A successful method to retrieve nematodes from organic material is a mist chamber (Seinhorst). In a mist chamber a very fine mist of warm water (20 degrees) is sprayed from nozzles every half an hour during 15 minutes. The organic material is wet all the time; the nematodes emerge and move through a 150 u sieve and are collected in a collection dish with overflow. The nematodes sediment to the bottom of the dish. This takes some time depending on the toughness of the plant tissue, The method might work for litter too, If suitable send an e-mail for more details.

    regards Thomas

  • Modal Testing: Why do I have an unnatural mode shape?

    Good day,

    I have been working on bone dynamic characteristics with using modal analysis procedures.

    Boundary conditions are free-free

    Accelerometers: B&K 4507B 

    Impact hammer: B&K 8206-001

    I have used line fit method to make parameter estimation. However, my result seems a little fuzzy. According to FRF, I would have first bending mode on 770 Hz, but my mode shape is seen like below. How can it be possible? Is it Some sort of a measurement problem or a physical phenomena? My point FRF is also point 7. Becuase of this, it is probably a measurement problem.

    Thank you for your concern and valuable advice.

    Claes Richard Fredö · Qring Technology Intl. AB

    Perhaps I should clarify that for the impact hammer, the weight you need to account for is the tip mass plus the weight between the tip and the force sensor element. You sometimes find this weight stated in the transducer data.

  • Daniele Spinelli added an answer in Glucokinase:
    How to measure hepatic glucokinase activity?

    I would like to use a colorimetric assay to measure glucokinase activity from hepatic extract. Does anyone have experience using any commercial kit?

    Daniele Spinelli · Università degli Studi di Siena

    According to Sigma Aldrich protocol, you can prepare samples using the following final assay concentrations: in a 3.00 ml reaction mix, the final concentrations are 60 mM Tris, 20 mM magnesium chloride, 4.0 mM adenosine  5'-triphosphate, 12.0 mM glucose, 0.9 mM ß-nicotinamide  adenine dinucleotide phosphate, 10 units glucose 6-phosphate dehydrogenase and 0.025 - 0.050 unit glucokinase. Monitor the  A340nm until constant using a suitably thermostatted  spectrophotometer. One unit will phosphorylate 1.0 µmole of D-glucose to D-glucose 6-phosphate per minute at pH 9.0 at 30°C.

  • What are the factors affecting shelf life of suji (sooji)?

    Can anyone help me how to increase the shelf life of suji (sooji). What are the factors affecting shelf life of suji?

    Santhakumaran A. · Indian Institute of Crop Processing Technology

    Your are a Food engineer, you must know that the primary causes  are moisture, temperature , microbial factors and so on  

  • Manuel Morales added an answer in Hadron Physics:
    Is it possible to derive quark masses from photon wavefunction?

    In a 2011 paper, Gersten and Moalem derive among other things photon wavefunction and wave equations for massless particles of any spin. Is it possible to derive quark masses too using their approach?

    Manuel Morales · Institute of Prephysical Research

    "At least he is able to derive top quark mass. "

    And by what means is he able to prove it? As the unambiguous empirical evidence has shown, what we call "fundamental" in physics is not fundamental at all. It is conjecture based on effects. Unless we know which fundamental selection event caused the effect of a supposed quark, we are simply guessing and then trying to convince each other that our guesses are correct. See link: 


    It is important to speculate in order to conduct science. It is another matter altogether to use speculation as a substitute for science.

  • Olga Shnaybel added an answer in Aging:
    Does anyone have any studies to share on productive aging?

    any studies to share on productive aging?

    Olga Shnaybel · International Center of Revitalization and Rejuvenation LLC “La Lik


  • Can we perform Raman Spectroscopy on Quantum Espresso?

    Is it possible to calculate Raman spectra using (1) VASP or (2) Quantum Espresso?

    Shaban Ahmed Ali Abdel-Raheem · Agricultural Research Center, Egypt


  • Benhur Medija added an answer in Organic Chemistry:
    What are the possible starting materials for the synthesis of benzothiophene?

    Please provide journals about this matter. Thanks everyone. God Bless

    Benhur Medija · Mindanao State University - Iligan Institute of Technology

    Thanks everyone

  • What do you think about new map of global ecological land units?

    Last day US Geological Survey (USGS) and Esri released new map of global ecological units. Here is the information: http://blogs.esri.com/esri/esri-insider/2014/12/09/the-first-detailed-ecological-land-unitsmap-in-the-world/?utm_source=esri&utm_medium=email&utm_term=78724&utm_content=article&utm_campaign=globe_2014

    What do you think about it? Can it be used in spatial planning in your country?

    Sayed Zaheen Alam · University of Delhi

    Dear Piotr

    1. The Ecology (I know you know) means “ study of interactions among organisms and their environment”
    2. It is misleading to say that “global ecological land units” since ROLE of “ORGANISM” (among and Environment) is not clear in four mega parameters i.e., bioclimate, landform, lithology, and land cover parameters. It should be renamed such as "LAND ECOLOGICAL ZONES"
    3. At a base resolution of 250 meters it may not yield better results for micro or meso level planning units.
    4. In India we already have much better “spatial” unit for the “planning purpose” in the form of “agro ecological zone” = agro-climatic-zone {Climate (rainfall, PET and mean temperature)+ LGP } + superimposed on Landform (act as modifier of Climate and LGP) with specific range of potential and constraints.


  • Denis Havlik added an answer in Laptop:
    How Power can be transmitted via Air-interface ?

    I am trying to find is there any technology which can transmit power without wire in air medium.This will help to make wireless electric supply like wireless laptop changer or blue-tooth LAPTOP OR MOBILE CHARGER?

    Denis Havlik · AIT Austrian Institute of Technology

    The usual way is with induction. You basically put an electromagnet in the device and one on a table, and let them exchange the energy.

    Basically the same thing happens when you send any kind of radio-waves out of an antenna and then receive the waves on the other end. Unfortunately, transferring the energy over longer distances is because of dissipation. Inverse-square law for non-directional antennas. Better for directional ones, but losses will in most cases be enormous.

    As for transferring of energy over bluetooth, I doubt that this will make you happy. Bluetooth is designed to transfer data over the room or even over the street. The energy which could be transferred is very low, disipation high...

    What *can* (and is) be done is NFC energy transfer. Still low-energy, but enough to power the passive NFC chips and this is a near-field device, so the energy loss is less of a problem.

  • Which are the requested conditions for a systematic Theology in dialogue with Culture today?

    It seems difficult to think in something like a Summa Theologiae today. But this would be possible in contextual dialogue with culture.

  • Can anybody help me regarding the mathematical study of plant extract?

    why we need to use cumulative yield while plotting the graph of yield vs time instead of using non-cumulative? since for thermal labile compounds, the degradation (reducing of yield) observe for non-cumulative data vs time. this will describe the mechanisms of extraction rather than cumulative yield for thermal labile compounds. sorry for obvious misunderstanding on the concept of extraction compounds from plant. 

    Nidal Amin Jaradat · An-Najah National University

     ratio of the extract yield to total weight

  • Balázs Farkas added an answer in Testudines:
    Does anyone have any population/abundance or non-CITES trade data on Heosemys spinosa?

    I am doing a dissertation at Uni on the trade in Heosemys spinosa so any data on trade or populations that you can provide me with me would be gratefully received. I naturally have the CITES trade data. Thanks.

    There are numerous reports dealing with freshwater turtle exports from Asia, but I am aware of only a single one specifically focused on the harvest sustainability of Heosemys spinosa (Mardiastuti 2008). As RG allows the attachment of single files only I would need your email address so I can send you those I have pdf copies of. Just let me know in a private message.

  • Anthraquinone biosynthesis required?

    I need research article or research report or thesis that elucidate anthraquinone biosynthesis and enzyme involved in pathway.  

    Please provide research articles by contacting me

    Nidal Amin Jaradat · An-Najah National University

    from acetyl COenzyme A

  • Maria Thomas added an answer in PPAR alpha:
    How can I evaluate PPAR-Alpha activity? What is the procedure for estimation of various enzymes like CPT, FS, FAS, ME, G6PD and ACAT.?

    I am focusing on PPAR-Alpha expression by estimating various enzyme activity (CPT, FS, FAS, ME, G6PD, ACAT etc.) from Rat Liver homogenates..

    I don't have the exact procedure for estimation of these enzymes..

    Maria Thomas · Institut für klinische Pharmakologie

    Hi Bhavesh, I am not sure whether I understood your question correctly: PPARa is in first line transcription factor, thus its activity should be reflected in the measurments of the levels of ist downstream target gene expression, i.e. ACOX, CYP4A11, CPT, PDK4 and many others by using usual quantitative RT-PCR. Assessement of the activity of the enzymes you named will not nessesarily be the indicators of PPARa activity since enzymatic activity of CPT, FS, FAS, etc can be additionaly regulated via plenty of other factors. Correct me if I misunderstood your question and Good Luck!

  • Q. Song added an answer in Image Classification:
    For natural image classification tasks, how to collect good training and testing images from scratch? That is, how to build a good image dataset.

    Now I have a project that needs me to build the training data and testing data (in this context, data means images) from scratch, so that a classifier (e.g. SVM) can be trained and tested.

    Any good criteria to build training and testing images? I do not mean how to extract features or how to split between training and testing images. What I mean is how to collect a good image dataset.  

    Q. Song · Nanyang Technological University

    Fro image process automatically, you still need to extract features through conventional techs, no matter the images are from apps or something else. Then you need to do the classification or data mining and so on.

  • Nidal Amin Jaradat added an answer in Nitrous Acid:
    How do remove nitrous acid from diazonium solution?

    Via add urea to solution or sulfamic acid.

    Nidal Amin Jaradat · An-Najah National University