Q&A

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  • What are the possible measurable objectives for climate change impact and adaptation assessment?

    Looking for possible measurable objectives to answer the following questions:

    How has climate change affected the quality and quantity of water resources?

    What is the extent of climate change impacts on socio-economic use of water resources?

    Ishmael Lente · University of Ghana, Ghana, Accra

    This is great, stay blessed Paul.

  • Peter T Breuer added an answer in Server:
    How can I develop a server that spawns 5 child processes with 3 seconds the client connection?

    We need to develop a server that spawns a child process at any time a client tries to connect to your server. The server should connect to equal or less 5 client process at once. Every 3 seconds the client connection, it send a message include its PID and the count value (how many times the server receive a message from the client). The parent will response by echoing the data received back to the client.

    Note: We can use the check out the sleep ( ) system call

    Peter T Breuer · Birmingham City University

    This is just the normal way of programming a server. You'll find parameters like the queue length as things you can twiddle in the usual TCP/IP socket setup.

    IOW, this sounds like a programming exercise you have been asked to do. Why not consult the notes given to you or the person who set it (as well as the fine manual page for socket(7)).

  • What is the relationship between foreign languages learning and economic growth?

    Could you please help me finding references regarding the relationship between foreign languages and economic growth?

    Thanks in advance,

    Syamsul Fozy Osman · Kolej Poly-Tech Mara

    The Malaysian government gives emphasis on learning a second language (English) and encourages the development of an extra language. It is made the second shift of the Malaysian Education Blueprint. Please refer to the attachment.

  • What is the maximum adsorption time required for Rabies virus into PCEC ?

    I would like to know from your experience, the ideal rabies virus adsorption time on to purified chick embryo cells?

    Selvaraj Jagannathan · Pasteur Institute of India

    we optimised at various temperatures (35,36 and 37) at 45 minutes sir

  • Is there any forcefield which is applicable for both small molecule as well as peptides?

    I need to do docking for peptides as well as for small molecules. So in conern to maintain uniformity in my methology, I need a forcefield which can be applicable to peptides as well as small molecules

    Fidele Ntie-Kang · University of Buea

    MMFF94x

  • Can anyone recommend a CW laser system of 808 nm that I can use to treat rats injected with nanoparticles?

    Can anyone recommend a CW laser system of 808 nm that I can use to treat rats injected with nanoparticles. I have a portable CW diode laser (Chanchung New Industries Opto electronics Tech.co. Ltd) but I am not convinced that this could be used to illuminate the whole tumor in the animal. 

    Ramya Chandrasekaran · Monash University (Australia)

    Dear Boris,

    The idea is to kill the tumor cells through the heat produced by NPs  (widely known as photothermal therapy). And at this NIR wavelenghth, tissue absorb very minimum light which wont be sufficient to kill the cells. so, the nanoparticle and the laser, both work as a combo in destroying tumor cells.

  • Can anyone help to identify this egg found on a fecal float?

    Fecal flotation was performed on feces from a sheep and a donkey at different times and from different locations in Grenada, West Indies.  The following egg was found in both fecals.

  • When it comes to simultaneity is Einstein correct or is Dingle correct?

    Albert Einstein claimed in 1905 that a single event can occur simultaneously at different times within two inertial reference frames moving relative to one another. In 1950 Herbert Dingle argued that different times cannot be simultaneous. I have analysed this conflict by deriving the Lorentz equations using both points of view. According to this analysis Dingle must be correct. See youtube presentation of this analysis at  https://youtu.be/4XLYzhHQ64Y

    Charles Francis · Jesus College, Cambridge

    Johan, I am really disappointed. Your last two posts are so unbelievably incoherent, that there is not a single thing I can pick on to make fun of. The only thing you do make clear is that you have not got a hope of repeating accurately what anyone has said.

  • Cristian Castro added an answer in Orchidaceae:
    Can anyone provide me differences between the two ochrid species Restrepia lansbergii and R. dodsonii?

    Hello,

    I would be very grateful for any morphological details allowing to recognize two Orchidaceae species - Restrepia lansbergii and R. dodsonii (first is known from Venezuela, Peru and Ecuador, the second is endemic to Ecuador).
    Maybe there is any key for identification plants belonging to this genus?

    Thank you in advance for your help.

    Best regards,

    Radomir

    Cristian Castro · Universidad Pedagógica y Tecnológica de Colombia

    Hi, this information (about the two species that you need) can you help and this link  have the peper of  a consideration of generic validity  the Restrepia pg :141 (is it's old, but it helps  http://ia600602.us.archive.org/24/items/mobot31753003541775/mobot31753003541775.pdf )

    Restrepia lansbergii Rchb.f. & H.Wagener

    • Breedlove, D.E. 1986. Flora de Chiapas. Listados Floríst. México 4: i–v, 1–246.
    • Govaerts R. (ed). For a full list of reviewers see: http://apps.kew.org/wcsp/compilersReviewers.do (2013). WCSP: World Checklist of Selected Plant Families (version Oct 2011). In: Species 2000 & ITIS Catalogue of Life, 11th March 2013 (Roskov Y., Kunze T., Paglinawan L., Orrell T., Nicolson D., Culham A., Bailly N., Kirk P., Bourgoin T., Baillargeon G., Hernandez F., De Wever A., eds). Digital resource at www.catalogueoflife.org/col/. Species 2000: Reading, UK.
    •  Hamburger Garten- und Blumenzeitung 21: 300. 1865. (Hamburger Garten- Blumenzeitung)
    •  Rchb.f. & H.Wagener. 1854. In: Bonplandia (Hannover) 2: 23

    Restrepia dodsonii Luer (esta es la endémica de Ecuador)

    Imagen   http://media.eol.org/content/2012/06/14/21/78543_orig.jpg

    Acá puedes descargar la descripción publicada por Luer en Phytolgia en la página 382 y 383 http://www.biodiversitylibrary.org/page/13043934#page/400/mode/1up

    • Dodson, C.H. & P.M. Dodson. 1980. Orchids of Ecuador. Icon. Pl. Trop. 3: 201–300.
    • Dodson, C.H. 2003. Oncidium–Restrepiopsis. 4: 665–883. In C.H. Dodson Native Ecuad. Orchids. Colina, Medellin.
    • Govaerts R. (ed). For a full list of reviewers see: http://apps.kew.org/wcsp/compilersReviewers.do (2013). WCSP: World Checklist of Selected Plant Families (version Oct 2011). In: Species 2000 & ITIS Catalogue of Life, 11th March 2013 (Roskov Y., Kunze T., Paglinawan L., Orrell T., Nicolson D., Culham A., Bailly N., Kirk P., Bourgoin T., Baillargeon G., Hernandez F., De Wever A., eds). Digital resource at www.catalogueoflife.org/col/. Species 2000: Reading, UK.
    • Jørgensen, P. M. & S. León-Yánez. (eds.) 1999. Cat. Vasc. Pl. Ecuador, Monogr. Syst. Bot. Miss. Bot. Gard. 75: i–viii, 1–1181. Missouri Botanical Garden, St. Louis.
    • León Yánez, S., R. Valencia Reyes, N. C. A. Pitman, L. Endara, C. Ulloa Ulloa & H. Navarrete. 2011. Libro Rojo Pl. Endémic. Ecuador, 2 ed. 1–957. Herbario QCA, Pontificia Universidad Católica del Ecuador, Quito.
    • Luer, C. A. & R. Escobar Restrepo. 1996. Icones Pleurothallidinarum–XIII. Systematics of Restrepia (Orchidaceae). Monogr. Syst. Bot. Missouri Bot. Gard. 59: 1–168.
    • Luer, C. A. 1980. Miscellaneous new species in the Pleurothallidinae (Orchidaceae). Phytologia 46(6): 345–386.
    • Luer. 1980. In: Phytologia 46: 382
    • Phytologia 46(6): 382. 1980. (Phytologia)
    • Valencia Reyes, R., N. C. A. Pitman, S. León-Yánez & P. M. Jørgensen. 2000. Libro Rojo Pl. Endémic. Ecuador 2000 i–v, 1–489. Herbario QCA, Pontificia Universidad Católica del Ecuador, Quito.

    Espero sirva.

    Cristian C.

  • Girma Hailemichael added an answer in Nurseries:
    Does any one have the idea on extraction of seeds from hard fleshy fruits for nursery?

    Certain tree species have hard fleshy fruits and it is difficult to extract seeds from such species. 

    Girma Hailemichael · Ethiopian Institute of Agricultural Research

    There are various treatments for seed dormancy. If the dormancy is a type of double dormancy (hard seed coat) and some inhabitants, then you need to apply hard seed coat breaking treatments and again hormone applications such as gibberellic acid treatment. Check the type of dormancy first and act accordingly. Simple treatments such as hot water application and sulfuric acid acid application may solve the dormancy. It is better you mention the name of the species.  Good Luck

  • Nancy Liu asked a question in Autophagosomes:
    How to understand electron microscopy pictures for autophagy?

    Hi everyone,

    I am trying to identify vesicles at different stages in the autophagic pathway in the heart, especially autophagosomes.  However, the EM quality seems good, but I can rarely see autophagosomes in starved heart; I do see many large blank vesicles and some very small vesicles with irregular contents which are not electronic dense.  

    Does anyone have suggestions on literature with good EM pictures on autophagosomes?  Does anyone know if heart is different from other organs in terms of forming autophagosome? (I mean, since the sarcomere is so densely packed with myofilaments and mitochondria.....)

    Thanks in advance!

  • Saadi A.M Aldahaan asked a question in Ions:
    What is the simple method for the concentration of SO4 in the water?

    i want a simple chemical method and calculation for the presence of SO4 ion in the water?

  • Dirk J Gouma added an answer in Pancreatic Surgery:
    Would you participate on an international study of laparoscopic vs. open left sided pancreatic resection?

    The evidence on laparoscopic vs. open left sided pancreatic resection is limited. Up to now no evidence from RCT can be used to evaluate the value of the laparoscopic technique.

    Given the fact that the incidence of left sided resections is low even in centers for pancreatic surgery we postulate that it is necessary to perform an international trail. Would you be willing to participate?

    Dirk J Gouma · University of Amsterdam

    Dear dr Keck, dearTobias,

    Excellent research question.

    The DPCG (Dutch Pancreatic Cancer Group) recently started with a RTC on this subject and most centres will participarte

    pleaes contact Marc Besselink AMC for the details (M.G.H.Besselink@amc.uca.nl)

    Best regards

    Dirk Gouma

  • Daniel Rosquete added an answer in Algorithms:
    Any challenging Computer science algorithms?

    Hi,

    Do you have any challenging Computer science algorithms?

    Please pass the content or URL to me.

    Thanks

    Chandrakant

    Daniel Rosquete · Universidad de Carabobo, UC

    Hi!

    Maybe you should try the online judge that the University of valladolid has. The url is http://uva.onlinejudge.org/ there is one of the largest problem repository of all times. Plus, there is a status bar in every problem, so you can determine the difficulty.

    Hope it helps!

  • Jai Ghosh added an answer in Solution Chemistry:
    How do I avoid Cr2O3 solubility problems in OHM medium?

    I am preparing OHM medium (Fabregas, 2000) for H.pluvialis stock cultures. I have problems with Cr2O3 solubility in the stock solution as after autoclaving it I find a clear green precipitate inside the bottle. To confirm this I made to different stock solutions, one with all the component except for Cr2O3 and one only with Cr2O3, and actually only the Cr2O3 stock presents the problem. I also found that Cr2O3 is almost insoluble in water. Does anyone have any idea or suggestion about this issue? Thank you!

    Jai Ghosh · Shivaji University, Kolhapur

    In fact it does make a lot of sense to have an insoluble compound in culture medium. The only thing , in this case you must consider the toxic nature of the insoluble component.

  • Has anyone operationalized the construct of classroom formative assessment?

    Teachers claim to have relied on assessment than tests but many have just been breaking the final test into quizzes. What are assessment practices teachers can employ in their classes? How is the construct of classroom formative assessment operationally defined?  Any research has been conduced on this?

    Vrajeshkumar G. Khambholja · Birla Vishvakarma Mahavidyalaya Engineering College

    Perhaps to assess students during a Problem Based Learning assignment given to them, at all of its stages is a better way than the other traditional methods. There an instructor or teacher can assess their different skills during self study, problem definition work,  team work, group discussion, concept maps, presentations etc.

  • Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Bernd Schmeikal · University of Vienna

    Yes! The social ego space, Arnold's pet subject. Fine.

  • S. Xavier asked a question in Solvents:
    When we run run molecule by adding solvent in Gaussian, can call that molecule in solvent phase?

    We usually say the molecule is run gas phase in Gaussian.  If we were to add solvent to the main molecule,  can that still be called it is runing gas phase. If that is the case how to call a molecule status by adding a solvent.?

  • Bartu AVCI added an answer in Analytical Modeling:
    How can I model Adhesion between two layers?

    Hi all,

    are there any (analytical) models in the literature which study the adhesion characteristics between two layers?

    I am basically coating a substrate (metal) with polymer by using PVD, and interested in studying the adhesion.

    Thanks,

    Bartu

    Bartu AVCI · Harvard University

    Hi,

    i am using stainless steel. I was at first place looking for analytically models; but simulations might also be useful of course. How would you go with COMSOL? are there any example tutorials regarding this topic.

    Thanks,

  • Can someone help me to identify the following species (attached file)?

    The detail is available attached file.

    I am from Ethiopia. I got this plant from on old coffee plants and on perennial plants on Macadamia, Mango and Avocado. It become more invading during dry seasons. It seems a type of parasitic. Can any one help me identify it? I got the coffee trees attacked by this plant become very weak, almost dying. 

    Girma Hailemichael · Ethiopian Institute of Agricultural Research

    Thank you so much Dr. Rajesh Gupta for your response. I will communicate Prof. Chauhan with the link you gave me! Thank you once again!

  • Does anyone know some literature about teaching in the hunter-gatherer context?

    It can involve teaching, learning, imitation, emulation, demonstration, etc...

    Thank You!

    Habakkuk Azinyui Yumo · R4D International

    Hi Dasa,

    This paper may be helpful as well. Good luck!

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3049106/

  • How do you distinguish positive gates based on isotype control?

    Good day to everybody.

    May somebody help me. 

    I cannot understand the logic of making gate based on isotype control. Is there any formal rule of distinguishing "positive" gate? 

    In attached file some of my data, are the dot plots gated correctly?

    Big thanks.

    Siva Gandhapudi · University of Oklahoma Health Sciences Center

    Your first case 200 vs 400 events is not significant because you will be saying that 50 % of your stain may be from the background. In the second example you will be saying that 5 % of your stain is likely from background. In this case it might be good if this is best you can get for this assay, although you may hear  some arguing the other way as %5 may seem too big in terms of numbers.  

    I don't have any idea of what you are testing.  I may be more useful if i know more about what you are doing as i am thinking that it may be due to technical issue rather than isotype.

  • Manuel Schnabel added an answer in Solar Cells:
    What is the exact difference between ideal efficiency and Shockley–Queisser limit?

    Ideal efficiency = (1/q * E_g * I_inc)  /  P_in. For AM1.5, its maximum is 48% at 1.1 eV bandgap energy.

    Shockley–Queisser limit is 31% for a black body and AM0 spectrum. May you explain the difference further?

    Manuel Schnabel · Fraunhofer Institute for Solar Energy Systems ISE

    S-Q takes into account unavoidable radiative losses of energy. This leads to slightly lower current, because some electron-hole pairs recombine radiatively, and lower voltage, because the the maximum voltage is given by the quasi-Fermi level splitting which, while it can't exceed Eg, never reaches Eg either. For more details I'd suggest you read their paper.

  • Does denaturing gradient concentration range depend on what region of the 16s rRNA gene is amplified?

    The 1st link nature.com deals with amplifying V3 region then DGGE with 25%-65% urea and formamide.
    The second link deals with V6,V7 and V8 and gradient at 40%-60%.

    Since my proposal centers on using mice gut microbiota I thought it would be appopriate to use the gradient at the 1st link. While using V6,V7, and V8 regions would be helpful to me since I already know the forward and reverse primers used (primers - 3rd link). The 1st link did not write the primer sequence.

    Alison KM Hadwin · Simon Fraser University

    The region may affect the concentration range need, but the size of the amplicon is usually more important. Since primers targeting different regions generally amplify different sized amplicons, it will appear as though the region matters more than it does.  The community you are studying can also affect the gradient range needed. 

    Usually what I would do is run a range-finding gel first, with a few samples on a gel with a denaturing concentration from 20 to 80%.  When you visualize the gel, you will probably see that all the bands are found in a portion of the concentration range.  For the rest of your gels you can use the narrower range suggested by your range-finding gel.

    I would not use the primers mentioned in your third link, as they are meant for sequencing, not DGGE.  The amplicon is 1.5 kB, while DGGE primers will usually amplify an area of only a few hundred bases.  Also, DGGE primers will have a GC clamp on the forward primer.  It would be better to use the primers mentioned in the second paper as they are meant for DGGE.

  • How to add noise across capacitor voltage in matlab simulation of grid connected inverters?

    It is require to add +2volts of noise to the measured capacitor voltage  in the simulation of z source inverter. How can it be added?

  • Jai Ghosh added an answer in Chitinase:
    Is there an easy way to prepare colloidal chitin to be used for bacterial media ?

    I wanna check the ability of one bacteria to produce chitinase enzyme, in the literature it showed some methods to obtain the colloidal chitin, but last time I tried it, it failed, maybe because of the filtration step or some other reasons, if someone have experience with that, what could be an easy way for preparing colloidal chitin ?

    Jai Ghosh · Shivaji University, Kolhapur

    My dear friend if you dry the colloidal chitin then how can you call it "colloidal chitin". NEVER DRY THE CHITIN THAT YOU HAVE MADE COLLOIDAL" 

  • What method is best to use for measuring urinary protein and creatinine concentration in mouse samples?

    Looking for a reliable testing kit for basic science research

    Billy Joel Sanchez-Jacinto · Universidad Peruana Cayetano Heredia

    Dear : Greenhall

    The best method use for creatinina un CLinical laboratory is  enzymatic method because don't have interference with high bilirrubin, glucose, ketone bodies (acetoacetate) , cephalosporin is more specifity than colorimetric method (jaffe method).

    Total proteín  use pirogalol red methodd

    Best dishes

  • Jan Mühlig added an answer in Big Data:
    Are there user types or personas in Video-on-Demand?

    I am looking for user types or personas for Video-on-Demand (VoD), ideally based on quantititve data. Any coutry welcome. I am trying to further elaborate them based on big data.

    Jan Mühlig · Open Usability

    I know about the difference, but I take anything there is.