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  • Do you know any article that used the cannula to infuse the drug (peptide) in motor cortex for behavior test?

    I am looking any article that used the cannula to infuse the drug especially peptide drug in motor cortex region. could you please help me?

    Ravi Kant Upadhyay · Deen Dayal Upadhyaya Gorakhpur University

    See here is an article 

    Distribution of nanoparticles throughout the cerebral cortex ...
    www.ncbi.nlm.nih.gov › NCBI › Literature › PubMed Central (PMC)
    by EA Salegio - ‎2014 -
    Mar 17, 2014 - When nanoparticles/proteins are infused into the brain, they are often ... agents within the central nervous system (CNS) is a major problem in drug delivery. ... a final 2 min period prior to cannulae retraction to reduce reflux of infusate. ..... when trying to reach regions of motor control such as the brainstem.

  • Song LI added an answer in Desalination:
    What's the best material for building a solar desalination system's evaporator?

    I want to use this container as a solar desalination system's evaporator so it must absorb solar energy (heat) in order to increase water's temperature. I have to mention that it is not possible to use another material to isolate the container.
    I thought about glass, plastic, aluminium and even copper. They all have some advantages and disadvantages. what's your suggestion and why?

    Song LI · Northeastern University (Shenyang, China)

    You can compare the light absorption properties of these materials, especially the absorbance in the IR region.

  • Vilemar Magalhaes added an answer in Podcasting:
    How can podcasting be integrated into a language class?

    Internet is thriving with various podcasts. Very few language teachers are using this technology in classrooms.  We intend to explore the ways and means to make use of this fabulous resource to teach English as a foreign or a second language.  The use of technology obviously enhances the motivation level.  Those who are engaged with Computer Assisted Language Learning (CALL) as subject can benefit us a lot in this respect.

    Vilemar Magalhaes · Easy Way Intercâmbios

    Podcast can be added to the language class as any relia. Short ones are better to work with in class. Long ones are good for homewok, but seldom students can see them at home. Those commercial ones will probably help a teacher to work passive skills. But if the teacher has his students creating their own podcasts to publish online, then this will open a wide door to the classroom. Even if, the students are not the ones who are doing the presentation.

  • Matthew Wheal added an answer in Soil Analysis:
    Trace elements in filter papers?

    Is there any problem of cadmium pollution in soil samples filtration by filter papers? I know that there are some trace metals in filter papers, but I couldn't find any document whether filter papers contain Cd and which filter paper is better in determining the amount of Cd in soil samples. 

    Matthew Wheal · Flinders University

    Unfortunately even the "cleanest" filter papers (or any other consumable lab item) will have some elemental contamination, despite the manufacturer's claims (note that on p20 of the brochure linked above doesn't specifically mention Cd, and on p5 the table lists "typical values"). You will have to do some method blanks to see how much Cd you are getting. My previous lab often found Cd from the yellow colouring of pipette tips (200uL)  and centrifuge tube caps got into acid digestions of plant tissue.

    It depends somewhat on the sensitivity of your method. If the paper adds 0.1 concentration units to a reading, and your soils are 1-10 units, then it might be a problem. If the soils are 100-1000 units, then the paper won't change much in the scheme of things. If the paper contamination is variable, and the soil values are low/ near to the paper blank concentrations then you have a significant problem.

    The best course of action is to test each batch of filter papers (plus all the other items in your method) to see if their is a detectable amount of Cd (or whatever is your element of interest). If it is below detection limits of your analytical instrument, then you're fine. If you do see something, you have to choose between (1) looking for another brand with less contamination and (2) monitoring the background Cd level in blank samples and hoping the minimum level in your soil is much higher than the background in the paper. (Option 1 takes time, option 2 more quality control samples). Even with a new brand (or grade of paper) you will still have to test each new batch or lot, as the manufacturers may change their suppliers too.

  • Stephen Moston added an answer in Criminals:
    Did anyone study the perceptions of police officers about the use of non-verbal language in criminal investigation?

    I'd like to do a qualitative research about the relevance of analyzing suspects non-verbal language during police interrogation. I know this subjects has been developed by Ekman and others, but it seems like no one has ever done a qualitative study on policemen perceptions. Does anyone have some interesting information? Thanks

    I'm happy to send out copies of my work (some is already on Researchgate).

    Best contact: s.moston@griffith.edu.au


  • Hussain Saleem added an answer in Projects:
    Does anyone knows where to find the data base for construction projects of any type?.

    If you could share any of the relevant contents, I'm sure and confident enough to keep those for only educational purpose. Really appreciate your valuable information and comments. Thank you.

    Marimuthu K


  • 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

    Manuel Morales · TemptDestiny.com - Prephysics Research

    "You do need more than a clock. You need a ruler, and a way to define directions. You cannot even have a coordinate system without all of these things, unless you create it from fantasy. How will you determine a coordinate for an event, time as well as space, if you do not have a clock?"

    Charles perhaps you should be asking how can you have a clock without a selection first being made? What good is a clock that doesn't tick?

  • Can cyanobacteria take nutrients from the soil directly or only from the water?

    I'm looking for the sampling design to find out the relationship of soil and cyanobacteria mat which I found abundantly on the soil with different colour (Olive green mat, Black mat, Blue-green mat)

  • Could you suggest a valid and reliable measure for assessment of emotional well-being and competence for children aged 13-15? Possibly free of charge?

    My team is following two cohorts of children, intervention group has received a four year universal socio-emotional intervention delivered by teachers and controls were in standard school curricula. We are following them after 4 years and want to see if they have different outcomes regarding mental health. well-being, emotional competencies and problem solving. We are searching for measures. Thank you in advance!

    Lynn Hugger · Adelphi University

    The BASC-II (the Behavioral Assessment System for Children- they have an adolescent form) or the Achenbach Child Behavior Checklist are both inexpensive & widely used.

  • Lawrence Broxmeyer, MD added an answer in Brain:
    What is the purpose of the brain?

    Your answer is more than welcome. Technical answers will be highly appreciated, but feel free to prove you have "brains", so you can participate on this discussion regardless of your background. 

    Lawrence Broxmeyer, MD · NY Insitute of Med Research

    Evolutionary survival.

  • Ravi Kant Upadhyay added an answer in Botrytis:
    Does anyone can provide me with the main components of Botrytis selective media ?

    I am studying the different growth of botrytis cinerea on different growth media. BSM is one of the media, i want to try.

    Ravi Kant Upadhyay · Deen Dayal Upadhyaya Gorakhpur University

    A selective medium has been developed for the use in spore-traps to study the dispersion ofB. cinerea on gerbera grown in glasshouses.BSM and BSTM were shown to be suitable selective media for the enumeration of B. cinerea conidia from the environment. Botrytis cinerea is a polyphagous fungal plant pathogen that causes extensive damage to a wide range of economically important crops world-wide  and is the focus of many epidemiological and biocontrol studies.

    You can prepare own media for use by using following combination of components.

    Botrytis selective medium should contain(g l±1): glucose, 2; NaNO3, 0á1; K2HPO2, 0á1 ; MgSO4.7H2O, 0á2; KCl, 0á1; 1chloramphenicol (Sigma, Poole, UK), 0á2; pentachloronitrobenzene (Sigma), 0á02; Maneb 80 (80% manganese ethylene bisdithiocarbamate; Agrichem, Whittlesey, UK),  0á02; rose bengal (Sigma), 0á05; tannic acid (BDH, Poole, 3,4UK), 5; agar no. 3 (Oxoid, Basingstoke, UK), 20. The pH
    was adjusted to 4á5 with 1 mol l±1 NaOH prior to addition of the agar. The medium should brought to the boiling with constant stirring and pour whilst still hot. For practical purposes this medium is not to require autoclaving due to its
    high selectivity. The colour of BSM varies with pH and should be opaque pink when poured. Botrytis spore trap medium (BSTM) differ from BSM in that Rubigan (12%
    5fenarimol; Dow Elanco, Hitchin, UK), 0á1 ml l±1, replace rose bengal. Diluted, supplemented Malt Extract Agar  (dsMEA) contained (g l±1): Malt Extract Broth (Oxoid), 4; chloramphenicol, 0á2; rose bengal, 0á05; agar no. 3, 15. This medium, with an unadjusted pH of approx. 5á4, should autoclave at 121 °C for 15 min. Kritzman and Netzer 6(K & N) and Kerssies (KERS) media.

  • What leads to failures of countermeasures against invasive alien species?

    Can some one recommend studies where countermeasures against invasive alien plants have failed. An ideal study would give a detailed account of the "ecologically based control strategy" and why it failed to eradicate the targeted invader. It would also recommend and probably test new control strategies.

    Hein Van Gils · Min of Environment & Tourism, Namibia

    To design the ideal control measure of invasive alien plants, the insights of the attached articles could help. The ground rules would be restoration of ground and canopy cover of the indigenous flora. In parallel, land management/ownership of the restored vegetation cover probably needs to be changed (burning; access and so on). The state is often not the ideal land manager. For canopy cover restoration, a non-evasive exotic tree species may be helpful in some cases as an intermediate step.

    Indeed costly failure prevails.

  • Gourav Shrivastav added an answer in Energy:
    How can we solve energy drift in NVE (constant energy, constant volume, and constant number of particles) ensemble in Molecular Dynamics?

    How can we solve energy drift problem in NVE (constant energy, constant volume, and constant number of particles) ensemble in Molecular Dynamics?

    Gourav Shrivastav · Indian Institute of Technology Delhi

    yes, you are right that there are rounding and truncation errors.  in normal case, 5 kCal/mol.ns is considerable change in NVE ensemble as per my knowledge. but if it is continuosly falling than you have to check where is the problem. Have you tried longer runs?

    Another aspect is that your potential energy is stablized and temperature is stablized then kinetic energy should also be stablized ( K.E = 0.5 kBT). Now, total energy = PE+KE, so your total energy should  also be stablized. Check the algorithm of NAMD or writing file section, if it is  giving something else.  You can do one more check, from nve you have idea about the average temperature of the system, setup one NVT run followed by NVE run and see if your drift is decreasing.

  • How do you mathematically calculate the flow stress of aluminium material?

    In hot forging process, hot compression tests are used to calculate the flow stress or Forging Simulation software can predict flow stress. I want to calculate the flow stresses of aluminium alloy via phenomenological models. Kindly Guide me.

    Ajeet Babu Kumar Parasumanna · Automotive Research Association of India

    Thank you. I am currently using Zener Hollomon parameter to correlate with grain size, Yeild strength etc.,

  • Merlin Franco added an answer in Ethnobotany:
    Are vernacular names a clue to scientific identity of plants?

    No doubt vernacular names are useful in identifying the plant scientifically but it is not always possible since a single vernacular name may refer to different plants in different area. Moreover a single plant is variously named by different community/tribes.

    Please provide your valuable suggestions.

    Merlin Franco · Curtin University Sarawak

    I Agree with Dr. Rainer.

    Ethnotaxonomy is an emic  system of classification. Vernacular names can vary depending on the individual and communities.

    Communities are often the pioneers in identifying and recognising plants/animals. Most scientific expeditions utilise the services of local/indigenous people who 'guide' them to the species. These are the unsung heroes of  modern Taxonomy. If we are looking at Ethnotaxonomy for clues that might lead to the discovery of new taxa, then I would  say that these systems are 'reliable' in that context. 

  • Wong yee Choong asked a question in Tropical:
    What are the measures that need to be considered when applying greenery system onto existing single storey terrace house in the tropics?
    1. How can green facade system improve thermal performance of a single storey terrace house in tropical environment?
  • Renda Agung asked a question in Fuzzy Logic:
    Prediksi beban jangka pendek?

    using ANN and Fuzzy Logic.

  • Kathleen Salse added an answer in Tai Chi:
    Does anyone know of published studies on aerobic activities vs anaerobic activities increasing cognitive function in older adults?

    I am unable to find published clinical studies regarding:  In the female older adult (65 & older) will aerobic versus anaerobic activities increase cognitive function?  Aerobic act- meaning cardio exercises (aerobic exercises, running, step-machine, bicycling)  Anaerobic act. - meaning yoga, stretching exercises (tai-chi), playing cards, Sudoku.

    Kathleen Salse · Loyola University Chicago

     Thank you Florentino Huertas, I will read it,.  

  • Any comments on ER-/PgR+ breast tumour immunophenotype by IHC?

    I recently signed out a breast incision biopsy with a diagnosis of "Invasive ductal carcinoma with ulcertaion to the skin, Nottingham histologic grade 3". The immunohistochemistry profile repeatedly done twice show a ER-/PgR+ result with moderate staining intensity in approximately 60-70% of the tumour cells. I have reservations on pre-analytical issues of specimen preservation which I believe may be the reason for this staining pattern.

    Rowen Tayag YOLO · University of Santo Tomas

    Thank you Dr Niedobitek. Unfortunately, the biopsy material turns out to be pure tumour with no normal surrounding breast ductules. Nevertheless, if the patient will ever undergo a definitive surgery like a mastectomy, I will surely repeat the biomarker testing again.

  • Vasanth Kumar asked a question in Archery:
    What data can be looked in Archery and Shooting performance analysis?

    Dear all,

    Will be happy to know about the performance analysis (the areas to be looked into) in archery and Shooting to improve performance. Have planned for a 2D video analysis (3 Cameras, aerial, Lateral and posterior) and force distribution Center of Pressure (COP) between the foot using AMTI Force plates. However, need more literature support on this and any possibilities of incorporating 3D Mocap technology and any other additional available technology to this?

    Available normative data and any further guidance will be of great support. 

    Thanks in Advance.

  • Should I do a pilot study to have the reliability of that questionnaire?

    I am framing a study regarding sleep abnormality of OPD patients in our hospital. A questionnaire is adopted from a website of Indian institute! Should I do a pilot study to have the reliability of that questionnaire! If yes, how I can set for it? I myself or my colleagues have zero practical experience of it!

    Rajat Sanker Roy Biswas · Chattagram Maa Shishu O General Hospital, Agrabad, Chittagong, Bangladesh

    Thanks Sir for critical explanations and providing me some interesting Insight!

  • Eric B. J. Harris added an answer in Ozonolysis:
    Can anyone suggest a logical mechanism for the ozonolysis performed by Leo Paquette (see attached file)?

    I've got an idea but not too satisfying.

    Eric B. J. Harris · Australian National University

    Ozonolysis of enones is complicated and generally results in additional cleavage of the carbonyl-alkene sigma bond. A simplified mechanism only giving a single rearrangement to the bicyclic trioxolane is given below.

    The exact mechanism is significantly complicated, and varies with the temperature and the number of equivalents of ozone absorbed. Both carbonyl oxide intermediates can form and can recombine intermolecularly to give a tetroxane which also decomposes to the anhydride.

    For an in depth mechanism of ozonolysis of a related compound, verbenone see the following:



  • Is there a relation between the functions with the same hessian?

    Suppose that we have two functions f and h on a riemannian manifold M. If Hessf =Hessh can we get a relation between both functions.

    Sameh Shenawy · Modern Academy

    Thank you Jacques Lafontaine.

  • Lawrence Broxmeyer, MD added an answer in AIDS:
    Where can I find age-structured incidence data for AIDS defining opportunistic infections starting from before AIDS epidemic in Sub-Saharan Africa?

    I am interesting in finding prevalence/incidence rates of specific opportunistic infections of young age groups (not adult) from before and after the start of the AIDS epidemic (~1980). 

    In particular I am looking for trends in: Tuberculosis, Cryptosporidium, and Non-Typhi Salmonella. 

    Does anyone know if such data exists and where I can find it? I would want to look in an area where HIV/AIDS is widespread, so somewhere in Sub-Saharan Africa would be ideal (or the whole region). 

    Lawrence Broxmeyer, MD · NY Insitute of Med Research

    "Where can I find age-structured incidence data for AIDS defining opportunistic infections starting from before AIDS epidemic in Sub-Saharan Africa?
    I am interesting in finding prevalence/incidence rates of specific opportunistic infections of young age groups (not adult) from before and after the start of the AIDS epidemic (~1980). 

    In particular I am looking for trends in: Tuberculosis, Cryptosporidium, and Non-Typhi Salmonella. "


    Very well. But why go to WHO? Perhaps you should start by seeking statistical data and maps for Tuberculosis and M. avium, which still are the leading causes of infectious death in HIV/AIDS. Before such typical and atypical mycobacteria were proclaimed "AIDS-defining illness" by the likes of WHO, you will notice that they admitted that tubercular disease killed close to 3 million people a year. Then since it has magically  "defined" AIDS -  it is now purported that tubercular disease kills merely a million and a quarter annually. Interesting math.

  • Imtiaz Mahmud added an answer in Gas Detection:
    Which is more important in ZnO nanowire gas sensor - crystallinity or aspect ratio and density?

    In case of ZnO nanowire gas sensor, gas sensing depends directly on oxygen vacancy which is closely related to aspect ratio. But what is the function of crystallinity? if my samples are well crystalline with higher aspect ratio and density, won't it give better sensing response than samples with low crystallinity and lower aspect ratio and density?

    Please share your ideas briefly...

    Imtiaz Mahmud · Kyungpook National University

    Thank you dear Tekmen. However, in case of ZnO nanowires, which is better, high crystallinity or low crystallinity? can you give me some reference please...

  • Kevin Loftis asked a question in DIG Labelling:
    Why during my zebrafish whole mount dig label ISH in the AP reaction step, is my staining showing up, but then quickly fading?

    During my DIG whole mount ISH in zebrafish when I get to the AP reaction stage my staining shows up bright and very specific, but fades after 30 min into the reaction.  There is no background that shows up after this.  I have tried heating the reaction at 37C to see if that would help, and have let the reaction go overnight at 4C and still nothing shows up after the initial stain that fades.  I do not understand why this is happening.  Has anyone else had this problem? 

  • Adrian Oncica added an answer in Microcontrollers:
    Does anyone have experience with a solar tracking sun position lookup table?

    In some PLC based solar trackers, real-time processing speed is too limited to use astronomical algorithms in high accuracy sun tracking. In precise solar tracking, a lookup table can be pre-calculated and the solar vector values (sun azimuth rotation and sun elevation altitude) stored in the lookup table or spreadsheet. With a pre-established lookup table, a PLC can obtain the position of the sun at any time and then the direction of tracking mechanism is adjusted to point to the direction of the sun, much like tracking preset waypoints in (solar) navigation in a time-synchronous manner. Was hoping researchers can share practical challenges or complications with Eprom type lookup tables in PLC or microcontroller environments.  

    Adrian Oncica · Astronomical Institute of Romania

    I appologise for my ignorance or confusion. What "precision" stands for here? Dispersion of computed values (as needed by solar optical observations, THEMIS) or error in computed values (as needed by solar energy collectors, NREL)? And what is the target value of this "precision" to be achieved (absolute or relative to what)? Once this clarified it sets the computational speed needed as the Sun drifts with half a degree (one diameter) in 2 minutes. Have you considered using a small lookup table of a limited number of trigonometric functions values? In this way you can avoid calling trigonometric functions inside the algorithm (as in the early ages of electronic computers).