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  • Is there any revision of the genus known Astylus (Coleoptera: Melyridae) or bibliography of this family to South America?

    I seek a revision of the genus Astylus ( Coleoptera: Melyridae ) or bibliography of this family to South America . There is a population of a species in southern Peru I require check. Thanks

    Abdhiel Arnaldo Bustamante Navarrete · Universidad Nacional San Antonio Abad del Cusco, Cusco

    Gracias por la informacion (y la identificacion) de la especie. Espero no sea demasiado solicitarle a usted la descripcion original de esta especie, si usted la tuviera. La busque mediante la referencia pero no tuve suerte.
    Gracias de nuevo por su tiempo

    Thanks for the info ( and identification ) of the species. I hope not too ask you the original description of this species , if you have one. The search by reference no luck .
    Thanks again for your time

  • Does anyone know how to implement the Ordinary Differential Equations in MATLAB that describe the calcium oscillations?

    I am trying to generate calcium oscillations using the ODE's that describe calcium signaling. I am not sure what equations should be specifically taken into account. Should I use the function ODE45 to obtain the solutions?

  • Does anybody know of a voltammetric approach to study the "feedback response" of a soil system when disturbed by organic compounds?

    I´m trying to start an study on the behavior of soil system when it is disturbed by the adding of organic compounds from plants extracts (specially allelochemicals such as secondary metabolites) by using voltammetry. This study can comprehend the interactions between the natural organic matter present in the soil sample (such as humic substances) or another soil component and the allelochemicals. Any ideas? 

    Eduardo Macedo de Melo · Federal University of Santa Catarina

    Thanks a lot Mr. Nicola.

  • Nino Dal Dayanghirang asked a question in Cambodia:
    What's the most important complimentary public health interventions to eliminate schistosoma mekongi in Cambodia and Lao People's Democratic Republic?

    Cambodia and Lao People's Democratic Republic has been providing preventive chemotherapy against schistosoma mekongi to endemic areas for several years with good coverage.  It has been recognized by WHO that this areas can potentially eliminate schistosomiasis.  With decreasing donor support, which complimentary public health intervention do you think is the most important for the national programme to implement to eliminate schistosomiasis as a public health problem in the Mekong river basin?

  • How can I improve the transfection efficiency when the gene is large?

    I am using TransIT-293 as the transfection reagent for viral packaging. However, when the gene is big (in this case 4K), the trasnfection efficiency become very low(in this case, only 2% of the cells are transfected). Thus, I couldn't harvest any virus with detectable titer. Is there any trick to deal with big genes when doing transfection?

    Kai-Neng Chuang · Academia Sinica

    Thank you for your reply. I'm sorry that didn't describe it clearly. Actually, I used pHAGE plasmid and used GATEWAY system to insert my genes. The empty plasmid size is about 10K so the total plasmid size becomes 14K. I am sure that the low efficiency comes from the gene size since I  have transfected other genes with smaller sizes(0.7~2.7K) at the same time and they all worked well.

  • Have you noticed any case of failure to arrest by cardioplegia?

    Recently we had a patient undergoing coronary artery bypass surgery with cardiopulmonary bypass. The heart was still beating despite giving more than 300 mEq potassium in cardioplegia solution through retrograde and antegrade route. Adding adenosine was not successful too. Have you faced similar challenges? How did you manage it?

    Niket Arora · Madras Medical Mission

    If heart did not arrest despite perfusing through the Grafts intermittently, its definitely a problem with the solution.

    Changing the batch of CP had helped us at times in our institute.

  • How to select the unexposed group from cross sectional study design?

    In cross-sectional study design, i would like to select two different group of people with exposed and unexposed to the a certain occupational exposure. I can select the exposed group of people from the workers but how do I select the people into unexposed group? I should select it simply from the residence area to put them into unexposed group? Does the workers wear mask while working consider unexposed too?

    Thank you.

    Miguel Angel Castro Jimenez · (1,2) Magna Science Corporation SAS and (1) National Cancer Institute of Colombia

    Hi... I think you can reformulate the original question. In fact, a cross-sectional study is different to that with characteristics you describe. I agree with Susan. She describes two types of cohort studies (I think you need to choose one of these), and also says what a cross-sectional study is.  

  • What is the most appropriate technique for systematic archaeological survey in the high mountain (3000 m)?

    This is to investigate ancient human occupation of an area of paramo Central America over 3000m. It seeks to understand the social and cultural environmental adaptation to this area or in contrast to no temporary occupation of ancient society in pre-Columbian times.

    Vera Tyuleneva · Universidad San Ignacio de Loyola

    See the Cuzco Valley Archaeological Project, 1994 to 2000, directed by Brian Bauer, published in his book "Ancient Cuzco: Heartland of the Inca" , Austin: University of Texas Press. 2004. (http://utpress.utexas.edu/index.php/books/bauanc#sthash.av82N3by.dpuf)

  • 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.

    Ravinder Jerath · Augusta Women's Center

    Tausif , All the cones and rods in the retina have their counterparts in the geniculate nucleus of the thalamus and striate cortex in the occiput. These are networked with oscillations. The retina codes the size from less than a mm to long distance on miles . This coding is magnified by strial projections and transmitted to Reticular nucleus of the thalamus. The reticular nucleus of the thalamus "views"  the fovea or macular vision,that by virtue of processing in milliseconds allows our executive cortex to "figure out " what we see .

                  All this happens in our intra-personal space that I have default space. What we believe is external is coded internally by these pathways and fast oscillations. That is why some of the visual disparities are seen as described by Arnold . We are deriving our conclusion of external size and distance from internal processing that can be  in-accurate .

  • Sushant Gote asked a question in Machine Learning:
    I know Machine Learning. But what is the best way to represent formal association between Machine Learning and Perception?

    Perception is ability to sense, think and act accordingly. But still what is formal association is between these two ?

  • Robert D Phair added an answer in Skeletal Muscle:
    Are you familiar with Glycogen-autophagy in skeletal muscle?

    Glycogen-autophagy is known to occur in skeletal muscle. What is the fate of glucose resulting from glycogen-autophagy in skeletal muscle?

    Robert D Phair · Integrative Bioinformatics Inc.

    As you imply, ever since Bernard, we usually think of liver as the source of needed plasma glucose. I am not familiar with the special case of a newborn, but for skeletal muscle the dogma would say that cytosolic glucose is so rapidly converted to G6P that the cell is very unlikely to establish sufficient cytosolic glucose concentration to drive secretion through GLUT1 or GLUT4. Another issue is the total amount of glycogen available in muscle versus liver. Again, dogma would probably say we cannot supply glucose from muscle glycogen in sufficient quantity to sustain plasma glucose. If this generalization is false for newborns, I'd like to see the evidence. Interesting question.

  • Nino Dal Dayanghirang asked a question in Madurella:
    Is mycetoma (eumycetoma or actinomycetoma) a public health issue in your country?

    WHO recognizes mycetoma as a badly neglected disease, accurate data on its incidence and prevalence are not available.

    Mycetoma is a chronic, progressively destructive morbid inflammatory disease of the skin, subcutaneous and connective tissue, muscle and bone. It usually affects the foot but any part of the body may be concerned. Infection is most probably acquired by traumatic inoculation of certain fungi or bacteria into the subcutaneous tissue. Mycetoma was first reported in the modern literature in 1694. Because of the description of a case reported in the mid-19th century in the Indian town of Madura, it is also known as Madura foot. Mycetoma has numerous adverse medical, health and socioeconomic consequences for patients, communities and health authorities.

    Mycetoma commonly affects young adults, particularly men aged between 20 and 40 years, mostly in developing countries. People of low socioeconomic status and manual workers such as agriculturalists, labourers and herdsmen are the worst affected. Accurate data on incidence, prevalence and distribution are not available.

    Mycetoma has two distinct etiologies: fungal and bacterial. Infections with fungi such as Madurella mycetomatis are responsible for eumycetoma, and those due to bacteria such as Actinomadura madurae cause actinomycetoma. Eumycetoma is more common than actinomycetoma, except in the American continent, where the latter form prevails.The causative organisms can be found worldwide, but most cases of mycetoma are found in tropical and subtropical areas in the so-called “mycetoma belt”, which stretches between the latitudes of 15° south and 30° north, and includes countries such as Brazil, Chad, Ethiopia, India, Mauritania, Mexico, Senegal, Somalia, Sudan, the Venezuela (Bolivarian Republic of) and Yemen. The most affected geographical areas are those characterized by short rainy seasons and prolonged dry seasons.

  • Amit Kumar asked a question in Exposure Assessment:
    How would you generally rate exposure through recreation as compared to that through drinking, for surface water?

    I need an idea on comparison of exposure assessment for human beings in terms of drinking and recreation (for surface water). So if exposure through drinking is rated as ‘10’ on a scale of 0-10 then how you would rate exposure through recreation. Also if you can refer me to some related studies in literature then I would really appreciate it. Thanks.    

  • Cristina Prieto Olavarría asked a question in Pottery:
    I am looking for information about using volcanic ash as temper in pottery or ceramics. Anyone has information?

    Technology. Function. Provenance

  • Are architectural styles created consciously or do architectural styles emerge coincidentally?

    Why is the contemporary world, with a greater population of architects and historical records of architecture, unable to achieve a common, widespread architectural style in time and space: if the lesser population of architects in the past could create sustainable architectural styles in time and space then?

  • Vaibhav Mantri added an answer in Marine Sediments:
    Are there any relatively inexpensive methods of measuring sedimentation in sea water (up to 10 metres deep)?

    We are trying to see the effect of sedimentation on wildlife in Tanzania and we can't seem to find any effective but yet inexpensive way of measuring sedimentation. any advice would be much appreciated. 

    Vaibhav Mantri · Central Salt and Marine Chemicals Research Institute

    We have done some experiments to understand the sedimentation process in our seaweed cultivation farm. We have used small glass bottles with round bottom and placed them for 24 hr in  the field. The samples were collected and data was expressed over area of the bottle. The only precaution which you need to take is the bottles remained in the same plain as the topography of the sea bed.

  • Amit Kumar Garg added an answer in Optical Networks:
    Which simulation tool can be used to simulate hybrid WDM-TDM passive optical network?

    I have designed one network and I would like to evaluate the performance of that network. Parameters are latency, average power consumption, number of required wavelengths etc. to serve that network. Which simulation can be used to determine these parameters? Thank you in advance.

    Amit Kumar Garg · Malaviya National Institute of Technology Jaipur

    okk I will try it & let me ask if will have any query during simulation.

  • Ernesto Ron added an answer in Ichthyology:
    Hi, does anyone know the benefits of ray fins on fishes?

    I need to know the benefits of the ray fins on the Osteichthyes.

    Ernesto Ron · Universidad de Oriente (Venezuela)

    The ray fins are also subject to changes in its structure, that provide other important functions besides swimming and displacement stability. For example, the dorsal fin of the fishes from the family Echeneidae has been modified, to become the suctorial disc that allows fixed to the other animals with whom they live, such as turtles and sharks among others. Similarly, there are changes in the anal fin in Cyprinodontiformes to form the copulatory organ of males.

  • What is the importance of growing need to put in place a technology driven on line portal?

    The open university innovation Report 2013 published  by the UK-based Institute of Educational Technology identifies 10 innonovation in currency, but are yet to have profound influence on education.

  • Yabing Zhang added an answer in Fullprof:
    How to rietveld XRD powder pattern by Fullprof or GSAS?

    I am studying in SrTiO3. However, I do not know how to Rietveld the crystal structure of the sample. Anybody can help me? Thanks.

    Yabing Zhang · Chinese Academy of Sciences

    Hello, dear Manawan. thanks for your continuous help. the IPE operator is old instrument. I am so sorry that I do not get the SRM scan because of lacking standard materials. What a pity! The MAUD file I hit the refine button, but  I do not get the same result like your. the video is my operating process. I doubt that if i have a different vesion of MAUD with you. Whether can you send me a operating process? Thanks very much.

  • Kenneth M Towe added an answer in Climate Change:
    Is it time we shift emphasis from technological solutions to climate change & focus on the 'Human Dimension'?

    Is it not obvious that nature can heal itself, if only left alone, and it is we humans who need regulation? Many natural parks managers do just that; seal off the area from human interference to let nature heal and recover. It is classified as 'Strict Nature Reserve"by IUCN. Complacency and inaction are not advocated here, as many have misunderstood, but the shifting of focus from technology to the human being. As technology is no match for human greed, isn't introspection & restraining ourselves more relevant than developing more technology, which caused the mess in the first place, by making it easy for a few to consume more? Since technology is only a short term quick fix which fails after a short time, isn't the real problem our addiction to material consumption & our lack of understanding about human nature? Isn't developing more technology sustaining the addiction instead of correcting it, leading to more complex problems later on, needing more complex technological quick fixes like higher drug dosages, more ground troops & equipment, (along with their debilitating side effects) in the future? Isn't this the vicious addiction circle we are trapped in? As researchers, do we merely buy more time with technology OR go to the very root of the problem, the human being?

    A lot of hue and cry is made about climate change and the environment in general. Public and private money is poured into research to study its effects on the environment, sustainability etc. Should we study nature or ourselves?

    " Our studies must begin with our selves and not with the heavens. "-Ouspensky

    Human activities have been found to have a direct correlation to climate change and its impact on the environment(I=P x A x T, the Ehrlich and Holdren equation), in spite of what some complacent sections say to protect their own self interests.

    We hardly know about Human nature. We can scarcely predict human behavior. We need to find out why we think like we do and why we do what we do and why, in spite of all knowledge and wisdom, consume more than what we need, in the form of addictions to consumption and imbalance not only ourselves but also the family, society and environment around us..
    Humanity is directly responsible for all the unnatural imbalances occurring on the planet. Yet we refuse to take responsibility and instead focus on climate change, or fool the public exchequer with a 'breakthrough in renewable energy just around the corner'. We scarcely know what drives human beings. If we had known, all the imbalances around us would have had solutions by now, given the amount of money plowed into finding such solutions. Are we blindly groping in the dark of climate change because we don't know the answers to our own nature?
    Is it not high time we focus on what makes us human, correct our consumptive behavior and leave nature to take care of climate change? Why focus effort on 'externals' when the problem is 'internal'- 'me'?
    Aren't we addicts denying our addiction and blaming everything else but ourselves?

    " We are what we Think.

    All that we are arises with our thoughts.

    With our thoughts, we make the world." - Buddha 

    IMHO, We don't need to save the World. It is enough if we save ourselves from ourselves. The need of the hour is not vain glorious interventions, but self-restraint and self-correction!

    The Mind is the Final frontier.

  • Arup Barman added an answer in Higher Education:
    How do you deal with colleagues that try to hold you back and bring you down?
    While you try to do your work and "go the extra mile" in teaching and research, some of your colleagues try to hold you back and bring you down. This may be due to their complex of inferiority, unethical upbringing, jealousy, etc. How can you convince them that if you succeed in some endeavor, then the whole department/faculty/university succeeds? While you always try to be a good team player and try a constructive approach always keeping in mind how to get to a win-win situation, all the politics they do is a destructive practice where they only think about themselves and their personal benefits! How do you deal with this type of colleagues?
    Arup Barman · Assam University

    It is correct what Mr. Dr. satyprasad is expressing. We need to be me positive to all negatives colleagues. Oneday they will follow only positive. As I experienced positivity is the ay of life! Nobody can pull back unless one himself allowed to pull back. Many a time one become victim of jealousy only when victim allows jealous and respond. Igonore negatives, consider positive can be mantra for working with them peacefully.

  • Carolina Rs added an answer in Zymogram:
    Why a protein cannot be stained with nothing?

    Does anyone know why a protein cannot be stained at all? I've tried staining it with Coomassie, silver and zinc-imidazole (reversible staining). I'm working with an alpha-amylase of about 250 KDa... it's huge... I've already concentrated it and In order to identify it I always perform a zymogram, and I can always see my amylase on the zymogram, but I can never see it on a SDS-PAGE... Any idea? Is there any information about not stainable proteins?

    Carolina Rs · Universidad Nacional Autónoma de México

    Hello Viktor, thank you for your answer. In fact I think I have already concentrated a lot! From a cell culture of 500 L, I get 25 mL of cell lysate. I take 4 mL from this cell lysate and I concentrate it on an Amicon Ultra-4 filter device with a 100 KDa MWCO, so at the end I obtain 500 uL of concentrate lysate....  So, I'm actually concentrating 1000 fold!!! And I can't see it on a SDS-PAGE gel!!

  • Zee Jani added an answer in Density:
    How should I calculate density of solution using following data?

    How should I calculate the density of solution?

    solvent Density is 0.711 kg/m3 100ml MW x g/mol

    solute A Density1490  kg/m3 800mg MW y g/mol

    solute B Density1051 kg/m3 2.78 ml MW z g/mol

    Zee Jani · Universiti Teknologi PETRONAS

    thank you very much for both of Dr ruben and Dr ana i really appreciate the effort.

    Best regards

  • Which one is more effective: ethanol precipitation, PCR Clean-Up, or gel purification?

    I want to purify my amplicons (148 bp, 135 bp, and 106 bp length) after PCR amplification. I will try three different methods to purify my amplicons. There are ethanol precipitation, PCR Clean-Up, and gel purification. Which method gives the best result? Which one do you prefer?

    Ahmad Rizqi Kurniawan · Institut Teknologi Sepuluh Nopember

    Dear Jiri Koubek,

    Thousand thanks for giving me a clear example. I now get the point. I have performed PCR clean-up and hope I will get best result!

  • Could anyone help me to recommend any past studies that related to corporate zakat responsibilities?

    I am currently conducting a research on Corporate Zakat Responsibility (CZR), However there are lacking of past studies as far as I know. The main issue for this research is to come out with the appropriate model to use zakat fund for corporate social responsibilities specifically for shariah compliant companies. Your feedback is very much appreciated.


    Khaliq Ahmad · International Islamic University Malaysia

    There is old book, 'Zakat Management' it has many chapters since the book was an outcome of a conference on the topic of Zakat and published in Pakistan. 

  • Rasheed Hussain asked a question in Car:
    Removing Privacy-related content from a Picture?

    What are the technologies that could be used to preprocess an image before uploading it to some server, let say to a cloud storage.

    The scenario is as follows: I want to take a picture of some designated scene that includes people, cars (people in the car, their heads perhaps, and the license plates of the cars). Before uploading this picture to the storage, I want to preprocess it and remove any privacy-related content (the faces of the people, and the license plates of the car) that could possibly abuse the privacy of the people.

    Any knowledge of such methods (algorithms, papers of any sort) would be helpful and would be much appreciated.

  • Khaliq Ahmad added an answer in Business Models:
    Is online business-to-business (B2B) business model more profitable than the online business-to-consumer (B2C) business model?

    Alibaba runs an online business-to-business (B2B) marketplace, whereas Amazon and Flipkart directly sell products to end consumers (B2C).
    Alibaba's Indian unit has made profits in just two financial years since it entered India. On the other hand, India's largest e-tailer, Flipkart, continues to suffer loss even after more than six years of operation.

    Khaliq Ahmad · International Islamic University Malaysia

    B 2 B and B 2 C are two different sides of the same coin. B to B basically involved in derived demand from the ultimate consumers and worked on the basis of resales.  However, the economy of scale is there in B 2 B. Profit derived from the former is relatively fast and sustainable due to CRM. It works better in industrial goods compared to Fast Moving Consumer Goods  (FMCG).

  • Gema López Gorosave asked a question in Methodology:
    Experiencies matching curricula?

    I´m interested in knowing which criteria, indicators, methodologies are using in different Universities to decide when 2 programmes are equivalent. Any literature can you recommend me?