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  • Simulation model of plant disease cocoa

    I work  with cocoa  in Colombian. 

  • How are cognitive processes regulated from mother to offspring?

    Memory is genetically regulated from mother to offspring or its all influence by her experiences during gestational period. What influences or what determines the offspring cognitive process and memory?

    Sakthivel Govindaraj · University of Madras

    thank so much for all your suggestion and ideas..

  • Kittipong Tripetch added an answer in Oscillators:
    Could someone guide me through the problems of soft harmonic oscillators in Gaussian?

    Hi,

    This is going to be a tricky question to phrase given that I am not too familiar with the subject matter. I was discussing Gaussian results with one of the earlier developers last week. We (more from his side) got on the discussion of the error in reported energy being scrambled/nullified due to "soft harmonic oscillators" in the vibration of some groups, in particular rotating groups. 

    Could anyone with a lot more experience than I, expand on what I think he was discussing, and perhaps point me towards some literature. 

    Kittipong Tripetch · Keio University

    If the excitation is soft, the
    steady-state output is a combination of terms having frequencies
    equal to those of the natural and excitation frequencies, with the
    forced response being dominated by the natural response. (ALI HASAN NAYFEH)

  • Huawen Qi added an answer in Granite:
    Can anyone help me to explain the shape of an REE pattern from a muscovite granite (Central Iberian Zone, North Portugal)?

    I'm studding a pluton composed by a main porphyritic two-mica granite ( V granite) in which  occur small stocks of a fine grained muscovite granite with some concentration of tourmaline (L granite). Both granites have features of S-type granites and are late to post Variscan. However i don't know how to explain the shape of the REE from the L granite (attached file). 

    Huawen Qi · Chinese Academy of Sciences

    As you know, two-mica granite usually underwent extensive melt-fluid interaction during its final evolving processes. Maybe you should check some references about the topic of “Lanthanide tetrad effect in granite”, such as “The lanthanide tetrad effect and its correlation with K/Rb, Eu/Eu∗, Sr/Eu, Y/Ho, and Zr/Hf of evolving peraluminous granite suites” (Irber , 1999. Geochimica et Cosmochimica Acta, Volume 63, Issues 3–4, Pages 489–508).

  • How maternal intelligence transmitted to offspring via epigenetic mechanism or gestational experience ?  

    Maternal intelligence will transmit to offspring during gestation by epigenetically or by maternal experiences. if suppose intelligence is transmitted via germ cell then how maternal experiences influences on offspring intelligence? or via epigenetic mechanism means maternal intelligence will carried to progeny until the pregnancy?

    if suppose mother starts learning music or learning music instrument for the first time during her pregnancy period then how it will influence to her baby's postnatal interest of music or learning music instrument, and what is the mechanism behind this and how this music interest might have transmit to neonatal baby?   

  • Taissir Nouri asked a question in D:
    Could cancer cells consume D aa and not be able to convert it to L aa.?

    Could normal cells consume the D aa and then covert it to L aa for building proteins and cell use. On the other hand, could cancer cells consume D aa and not be able to convert it to L aa.?

    many references mention that "Only L-amino acids are manufactured in cells and incorporated into proteins."

  • James Varghese added an answer in Landslides:
    Can you help me in analyzing satellite imagery of September 2014 Indo-Pak Floods?

    Right now as I frame this question many are perishing because of the floods in the state of Jammu & Kashmir in northern India and across the border in Pakistan. The news says it is one of the worst floods in decades. There was torrential rain from the past few days leading to overflowing of rivers triggering floods and landslides. Since I am a Remote Sensing student my first thought was to study the perspective from space, therefore I started browsing through NASA’s WorldView and Earthexplorer USGS websites for satellite images of affected areas. MODIS and Landsat are quite helpful usually in studying and monitoring floods but I was not able to find a single satellite image without cloud cover. Obviously because of the heavy rains these locations are covered by clouds throughout. All I could lay hands on was of previous years’ satellite imagery of the location. I’m waiting for the next pass of Landsat, Terra or Aqua for a cloud free scene in the hope of scrutinizing the post disaster situation. Can anyone suggest what other sources of satellite imagery I should look for, preferably freely available ones? If you have any ideas on how I should approach examining this flood scenario, they are highly welcome. Is there any way to remove cloud cover effectively from satellite imagery by some image processing techniques? Kindly support with answers and relevant research papers.

    James Varghese · Universiteit Twente

    Dear Jon, thank you for your answer. I've been trying to search for LIDAR data as a source of elevation but I guess it may not be freely available. Alternatively I am using the currently available ASTER GLOBAL DEM, GMTED2010, GTOPO30 as a source of elevation data as they are freely available. There has been an updated release of SRTM (SRTM 1 Arc-Second Global - 30 m) elevation data from 24th Sept onwards but so far it has not been made available for my region of interest. Are there any agencies which provide LIDAR data for the areas in and around the flood regions?

  • Mingda Wang added an answer in Speleothem:
    How the Asian speleologists record the abrupt events in N Atlantic?

    Abrupt events, such as YD and H1, etc, have been recorded in cave deposits (Wang et al.,2001 and so many papers). However, could you tell me the mechanism behind it? What is the bridge for the signal transmit? The atmosphere or the ocean current (THC).

    Mingda Wang · Chinese Academy of Sciences

    Thanks, Dr.Naidu.

    Could you share some references to support the idea? Thanks. By the way, could you give some specific details about the atmospheric transmission? For example, westerlies or others? Thanks.

  • Caroline T Cheung asked a question in Embedding:
    At what point during paraffin embedding can we leave the samples overnight?

    We are embedding some tissue samples in paraffin, but since the protocol is quite long, we would like to leave the samples overnight and then finish the embedding tomorrow.

  • Taissir Nouri added an answer in Biochemistry:
    Why does the body prefer L-amino acids (to D-amino acids) and D-glucose ( to L-glucose). Any literature that provides the answer ?
    This is a follow up question to the question asked by Sriharsha Prabhakara on WHY THE BODY PREFERS GLUCOSE AS ENERGY SOURCE. Of course, I know about the stereoselectivity/specificity of receptors. But this is specificity about receptors to L-amino acids and D-glucose, I suppose, it is because of the fact that those stereoisomers (or enantiomers) of glucose and amino acids are the ones present in the body. Therefore, I do not think receptors can provide the answer.
    Taissir Nouri · Kent State University

    This is very interesting question. Could normal cells consume the D aa and then covert it to L aa for building proteins and cell use. On the other hand, could cancer cells consume D aa and not be able to convert it to L aa.?

  • Rishi K Jain added an answer in Inhibitors:
    PKA inhibitor

    Is there any standard assay for testing whether a commercial PKA inhibitor works or not?

    Rishi K Jain · Novartis Institutes for BioMedical Research

    If you ultimately want to use it in cells, you might want to see if the PKA inhibitor can inhibit CRE-luciferase or any CRE driven reporter in your cell of interest upon activation with agonists.  If you only intend to use the inhibitor in vitro, validating its activity in a standard biochemical assay monitoring kinase catalyzed substrate phosphorylation might be adequate (eg using commercially available kits from Promega , Millipore etc)

  • What are the possible measures that would prevent Ebola virus from spreading into new areas/countries?

    Ebola virus disease or Ebola haemorrhagic fever, is transmitted to people from wild animals and spreads in the human population through human-to-human transmission. Ebola was first discovered in 1976 near the Ebola River in the Democratic Republic of the Congo. Researchers believe that the virus is animal-borne and that bats are the most likely reservoir. Four of the five virus strains occur in an animal host native to Africa. Fruit bats of the Pteropodidae family are natural Ebola virus hosts. Ebola is introduced into the human population through close contact with the blood, secretions, organs or other bodily fluids of infected animals such as chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines found ill or dead or in the rainforest. The current and most severely affected Ebola affected countries are Guinea, Sierra Leone and Liberia. There is no FDA-approved vaccine available for Ebola. 

    (Any weblinks or references relevant to Ebola prevention would be much appreciated)

  • Jean Tinney asked a question in People:
    Request full text - "Older people's views of dignity and how it can be promoted in a hospital environment"

    Carole Webster and Karen Bryan

  • Thanh Nguyen asked a question in Filters:
    How to extract total DNA from water samples?

    I would like to extract total community genomic DNA from water samples. I tried to filter the water with filter papers then extract the DNA off the paper using PowerSoil DNA isolation. The DNA yield is very low. What is the better way that I can extract the DNA?

  • Navaneetha cm asked a question in Dust:
    What happens when I delete a message permanently from mobile?

    If we erase something from book or board  we are able to see the dust but in mobile that deleted message gets converted to what?

  • Irina Pechonkina added an answer in NATO:
    A referendum on full Scotland's independence is in progress. How will the results of this referendum affect the European Union, NATO ...?

    Scotland's independence could bring some reflections to some European regions such as Catalonia, South Tyrol, Flanders, the Basque Country. Even some ideas of ​​new state of Kurdistan can be dangerous, especially for Turkey who would like to become a member of the European Union. What are your concerns about, if any?

    Irina Pechonkina · Math and Physical Lyceum

    Novorossia is a bloody place nowadays. I agree, that the greatest idea, as being mentioned, is "to return to roots"In the long run, every ethnicity has their own right for separation. Governments have no right to ignore wishes of folks and social opinion of folks. Besides, the conflict must be solved by peaceful way, by means of consensus.To use wars as a way for washing money is a crime.http://www.youtube.com/watch?v=vflmOXEyBoE#t=185  

  • Christina R Bourne added an answer in Extension:
    How to concentrate large volume of protein?

    I'm working on a protein that is 75kDa in size. My dialysate containing the protein is extensively diluted and the volume is fairly large. What's the best way to concentrate my protein besides from Amicon?

    Christina R Bourne · University of Oklahoma

    A long time ago, I would put the protein in dialysis tubing and lay that on a bed of PEG 20,000.  The PEG will quickly (1-2 hours) absorb water from the protein solution.  It is best to keep this in some type of dish on a rocker, as otherwise the protein will form a sharp concentration gradient within the dialysis bag and could form precipitate.
    Good luck!

  • Dejenie A. Lakew added an answer in Epistemology:
    Is Control-Knowledge the Strongest Form of Knowledge?

    Many years ago, when I was still a student, one of my professors occasionally said that we would have only then "really understood something", if we would be able to /implement/ "it" technically or algorithmically.

    In more philosophical terms, the professor's aphorism amounts to the question whether Control-Knowledge (or: Instrumental Knowledge) is the /strongest/ and /deepest/ possible form of knowledge, or ---even more bold and radical!--- if Control-Knowledge is perhaps even the /only/ epistemic entity which truly and rightly deserves the label "Knowledge" at all?

    Or, more concisely: What is the right understanding of "Understanding"?

    This difficult question I would like to discuss with Epistemologists, Gnoseologists, Hermeneuticists, Philosophers of Science, and Philosophers of Mind.

    [18-Sept-2014]

    Dejenie A. Lakew · John Tyler Community College

    Is it not a little contradictory to use the adjective "control " to describe  a meta knowledge system of all possible search spaces and results or solutions to any conceivable quest and path - which amounts to say nature, as all things exist by obeying laws of nature whatever the circumstances are either chaotic or otherwise.  Control used in human knowledge is a set of constraints for a feasible domain of a search space for a designed and purposeful outcome. But to really address the concept described, it is better to find and use an other adjective. 

  • Jiaqi Luo added an answer in IDEA:
    Anyone has an idea on the xps fitting of Mn-3s?

    Should the FWHM and % Lorentzian-Gaussian should be kept same? Or any other rules should be obeyed?

  • Fred Croxen III added an answer in Geology:
    Any ideas for teaching geology to a blind student?

    I would appreciate any suggestions for effective methods for teaching geology to a blind student. 

    Fred Croxen III · Arizona Western College

    Dear Lora,

    I had a blind student three semesters ago in my physical geology.  It was a wonderful experience.  The college paid a student to accompany her to all class meetings.  She had software that would read test questions to her and I helped interpret any diagrams on the test orally. I also require a half-day field trip and made arrangements for her husband to accompany her because he knew her limitations better than anyone.  I spent one-on-one time with her describing and feeling textures of the various rocks, the feel of mineral cleavage verses fracture, and raised relief maps were very useful.  For contouring we made stacked styrofoam models.  I made a deliberate decision not to show videos that semester as well, and I think the class was the better for it. She did very well in the class, out performing many other less motivated students. One last funny event is one day while lecturing the building lost power and an emergency announcement came through informing us classes were cancelled.  She suggested we continue on so everyone share in her experience.  The class got a good laugh.  Good luck.

  • Ravindra Kumar Gupta added an answer in Fuel Cells:
    What thin films we can use as electrolyte in fuel cells?

    Energy

    Ravindra Kumar Gupta · King Saud University

    10 micrometer thick film of YSZ or CGO on 1-2 mm anode subststrate  is used for the SOFC application.  

  • Antonio Curcio added an answer in Cardiology:
    Ajmaline and Brugada Protocols - can anyone help?
    Does anyone currently have an institutional protocol or pathway in place, for Ajmaline challenge testing in Brugada admissions? I have found a lot of literature but would like to have a look at actual protocols in place at facilities.
    Antonio Curcio · University Magna Græcia, Catanzaro, ITALY

    I usually inject 10mg/min, hence going over five minutes total infusion. Continuous ECG recording. Was your question related to whether stopping or not the infusion on arrhythmias appearance? This depends on the setting you have (outpatient room, or EP lab)

  • Riaz ul Haq Tariq added an answer in Travelling:
    How to design a one-page questionnaire for foreigh tourists?

    Because travellers have limited time to answer my questionnaire, it is important to put exact items in a questionnaire.

    Riaz ul Haq Tariq · Government College University Faisalabad

    1.   Identify parameters or elements for which require information.

    2. Theses should not be more than five elements/factors.

    3. Develop in simple language two questions on each domain.

    4. Do not expect them to write answers. You will not get any where. Provide simple options on a three point scale.

    5. Add  open space for suggestions to improve facilities for tourists.

    I have never worked in this area but that is what appears logical!

  • Katheem Kiyasudeen asked a question in Hot Plate:
    Can acid digested manure sample using Kjeldahl digestor be used for AAS or ICP elemental analysis?

    Normally Gehardt Kjeldahl digester is used for digesting powdered samples using H2S04, 15% NaOH and a Kjeldahl catalyst for crude protein analysis. I would like to know whether I can digest my dried and powdered sample of manure using triacid (H2SO4, Nitric acid and Perchloric acid, 5:1:1 ratio) in Gerhardt Kjeldahl digester for AAS or ICP elemental analysis?. Or Is there any other methods using any other digester rather than digesting using conventional method of heating sample with triacid in a hot plate (It takes weeks to digest samples). Kindly advice.

  • Ulysses Duque asked a question in NCBI:
    Deposited at NCBI reliable?

    I sequenced new isolates of S. singaporensis collected from different islands here in the Philippines. A well known scientists who is also working on this told me that don't rely on the sequences at NCBI. I'm just confused

  • Palani Shanmugasundaram added an answer in Nature:
    What is NATURE?

    What is your opinion of Mother Nature?

    To some, nature is a phenomenon including plants, animals, the landscape, the earth, the sea, the river, the ocean, the sky, the sun, the moon, the tree, the flower, the galaxy, the universe and the creatures; to others, it is human psychology, human thought, human nature including hunger, thirst, anger; while some others tend to believe it is everything that lies beyond the scope of our senses and perceptiveness—to mention just a few possibilities!

    Palani Shanmugasundaram · Vels University

    Dear Sir,
    Everything under one umbrella Galaxy is Nature. But there are so many Galaxies in the Universe. Unless we penetrate the secret of the Universe till then it is difficult to know about nature.
    Dr. Shanmugasundaram P

  • Hossein Adelnia added an answer in Dispersal:
    What are the dispersion medium and solvents of PMMA?

    I prepared a PMMA nano-sphere and I want to disperse it in polymer matrix. I found that it disperses in water, but it gives a clear solution in DMSO. Does this mean that it dissolves in DMSO?

    I measured the nano-size for PMMA/DMSO (using zeta analyzer) and found it to be150 nm.

    Hossein Adelnia · Islamic Azad University, Shahreza Branch

    I dont know whether ethanol or methanol can dissolve PVDF or not !

    If so, it will be great !

    let me add that pure ethanol does not dissolve PMMA but water/ethanol mixture (in some specific compositions) does !

    So, if ethanol dissolves PVDF, use ethanol as the medium ! fortunately, I think it keeps short-term colloidal stability !

    I think finding a suitable solvent is pretty tough for your case, since PMMA is somewhat sensitive to most of organic solvents, while PVDF is a solvent resistance polymer !

    The last resort in my view :  as far as I know, PDVF is commonly synthesized by emulsion, and dispersion polymerization. So, if you can supply latex of PVDF (dispersed in water), it will become easy.

    Just prepare blend of two latexes, (PVDF and your synthesized PMMA) , then cast the latex blend and finally anneal them above Tg of the hard polymer !

    If fine powder of PVDF is accessible, disperse it in water ! and do the same ...

  • Hemant Thakkar added an answer in MMR:
    Can someone help me decide whether my study is Qualitative or Mixed Methods (MMR)?

    I am planning to conduct semi-structured interviews with up to 40 parents of severely disabled people across two countries (20 in India and 20 in New Zeland). In the end, if I end up using numbers to compare their responses (e.g. 'X' was reported as an issue by 15 NZ parents but only 8 Indian parents); does such 'quantification' make my study a Mixed Methods Research or is it still a qualitative study?

    Hemant Thakkar · University of Auckland

    Thanks Han

  • Hafizul Alim added an answer in Foundations:
    How can I create a scale model for a soil foundation retaining wall experiment?

    I need to evaluate load and displacement relationship of a retaining structure due to vertical load from adjacent footing. I need to know details about the modelling techniques and how get the load, displacement data from the experiment.

    Hafizul Alim · Lamar University

    Please explain in detail about the modelling technique, equipment that I have to use and if possible attached some papers.