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  • Kay Samuel added an answer in Cellular Spheroids:
    How can I make sections from spheroids?

    Our group wants to make IHC staining of spheroids and therefore we need to embed spheroids and make sections.

    So far we tried manual dessication of spheroids (wash spheroids in 1xPBS, fix them o/n in Histofix containing 4% Formaldehyde, 5min 70%EtOH, 5min EtOH abs, 10min Isopropanol, 3min Xylol, 1h 65°C Parafin), but here the spheroids clump together when centrifuging them shortly after each step.

    We also tried to put them in biopsy bags or biopsy papers and do automated dessication, but for smaller spheroids (<500µm) it is hard to find them afterwards and transfer them into the molds for parafin embedding. Also when cutting the parafin blocks later, it is hard to see the spheroids. I fear that especially the small spheroids are lost during trimming.

    Has someone experience with embedding and sectioning of spheroids or can recommend any prototol? Is there an option to stain the spheroids prior to parafin embedding in order to make them better visible, but that does not interfere with IHC staining?

    Kay Samuel


    you could try putting your spheroids into gelatin, agar or  matrigel and then embedding  for sectioning. This method was used successfully for sectioning and satining of encapsulated pancreatic islets



  • Alessandro Zanarini added an answer in Static Analysis:
    When does dynamic analysis give values of results less than 85% than that of the values obtained by static analysis?

    Is the structural orientation/ form/issues responsible for such a condition? 

    Alessandro Zanarini

    I would suggest that you consider the fact that your structure might behave in a completely different manner in dynamics compared to its static response. I would say that starting from a simple single dof system you can appreciate how flexibility and dissipation, as function of your real conditions, play a determinant role in the life of your system. Thus is really relevant to properly tune any dynamic model on test references.

    Hope this helps,

    my regards,


  • Ernest R Schockaert added an answer in Systematic Zoology:
    What are the components of zoological classification?

    please tell me  what are the components of zoological classification

    Ernest R Schockaert

     Oh, by the way: I am afraid Simpson will not be of great help. He was a strong opponent (together with E. Mayer) of Hennig and of the cladistic system. Hence he does not incorporate the cladistic taxa into the nomenclature as we should do today. 

  • Matthias Düngen added an answer in Thermoplastic:
    Is the vacuum infusion techniques suitable for thermoplastic composite?

    composite materials Is the vacuum infusion techniques suitable for thermoplastic composite?

    Matthias Düngen

    Usually the viscosity of thermoplastic materials is much too high for this process. Do you have any specific material in mind or a specific reason for using thermoplastic material as matrice?

  • Lauren Thomas asked a question in Meditation:
    Is there any evidence that using meditation techniques with children aged 6-9 can improve listening, questioning and responding to others?

    I plan to carry out a teacher inquiry with my year 4 class and introduce meditation during school time. 

  • Cristine Clemente dos Santos added an answer in Culture Media:
    Which of these two culture media is good for the growth of Staphylococcus aureus; the Mannitol Agar or the Tryptic Soy Agar?

    I am confuse which of the two culture media is the best for the growth of S. aureus.

    Experts, I need your help. :)

    Thank you. :)

    Cristine Clemente dos Santos

    Staphylococcus aureus is not a fastidious organism and grows well in many different types of media. Tryptic Soy agar (TSA) is a basic nutrient media that it will  support the grow of S. Aureus, however usually TSA II, also called blood agar is best for routine grow And isolariam of S. aureus. Mannitol Salt agar helps to differentiate between S. aureus from other species of Staphlococcus. CNA is also a good media for S. aureus . So it depends what it is your goal, is that cultivate and store strains of  S.aureus ? Then you use TSA . If it is to help isolate or diferenciate between species of Staphlococcus ? Then MSA will help.

  • Inusa Ajene asked a question in Pseudomonas syringae:
    Does anyone know where I can obtain a known isolate of Pseudomonas syringae pv tomato?

    I would like to identify and characterize the isolates i have found in my area

  • Ruediger Burkhard Richter added an answer in Waste Treatment:
    What are the recent research trends in enhancing the thermal treatment of mercury containing waste from Chlor alkali plants?

    I'm looking for the best way for enhancing thermal treatment for mercury containing waste from Chlor alkali plants.

    Ruediger Burkhard Richter

    Dear all,

    Seems to be, that my answers are too much on the practical side. - Sorry for that. Some months ago I raised a question on a similar topic and the response was zero:

    Why the Marktredwitz Plant as the first large scale mercury remediation facility is still misunderstood as a test plant in the English literature?  

    The world’s first large-scale facility for the treatment of mercury containing solid wastes was planned, built and commissioned by the Berlin-based company Harbauer in Wölsau, outside the city centre of the Upper-Franconian district town Marktredwitz, for the remediation of the “Chemical Factory Marktredwitz” aka CFM.
    This abandoned chemical manufacturing facility was founded already in 1788 and was considered to be the oldest in Germany. Remediation of the plant comprised selective dismantling of the highly mercury-contaminated building structure, dismantling and packing of highly contaminated plant components and erection of a physical-chemical / thermal (distillative) soil and rubble cleaning plant.
    Construction of the treatment plant started in mid-1992. Operation commenced in October 1993 including the first optimization phase. 50,000 metric tons of mercury-contaminated solid wastes were treated successfully between August 1993 and June 1996. Unfortunately the Marktredwitz plant is often misunderstood in the Anglo-American literature as a pilot-scale plant only[i]. The permitted facility design comprised as pre-treatment step for the entire sand and gravel fraction the Harbauer soil washing process, whereas at Marktredwitz solely attrition cells were used. Froth flotation was not part of the design.
    The mercury enriched hydro cyclone overflow < 100 mm was dewatered and transferred to the second main treatment step “vacuum distillation” performed by a three-stage thermal desorption rotary system.
    Since in the “Marktredwitz plant”, the main emphasis of the entire waste treatment process was on the thermal desorption part, no specific physical-chemical mercury separation devices in the soil washing section was foreseen.
    The Marktredwitz plant, as a ’proto type’, was the first successful large scale mercury remediation facility and one of the largest soil treatment plants in the world. In the official information brochure about the remediation case provided by the Supreme planning commission in the Bavarian ministry of inner affairs is mentioned by the authors Schweiger  and Wittmann [ii], that the treatment plant as the first plant of its kind worldwide is the same pioneer work as the foundation of the Chemical Factory 205 years earlier.

    Why the Marktredwitz Plant as the first large scale mercury remediation facility is still misunderstood as a test plant in the English literature? - ResearchGate. Available from: https://www.researchgate.net/post/Why_the_Marktredwitz_Plant_as_the_first_large_scale_mercury_remediation_facility_is_still_misunderstood_as_a_test_plant_in_the_English_literature [accessed Dec 1, 2015].

  • Eko Subha asked a question in Sorting:
    Comparison between NSGA-II and its implementation in C code and JMetal. Does NSGA-II implementation oppose against its concepts?

    what I understand about NSGA-II procedure from Deb's paper are:

    1. Generate initial population -> Fast non-domination sorting -> Binary tournament selection -> Recombination -> Mutation -> .... -> Pareto solution set (crowding distance assignment is used after reproduction steps)
    2. Fast non-domination sorting used twice, i.e. after population initialization and after parent and offspring population combination.
    3. In selection process, crowded comparison operator is used based on nondomination rank and crowding distance properties. So, crowding distance assignment need to be done before selection process, doesn't it?

    But what I get from Deb's c code implementation and NSGA-II of JMetal framework are:

    1. In Deb's c code implementation, selection process used by comparing two individuals dominance, crowding-distance, and random number [0,1] generation. For example: given individual i and j for parent selection. If both of them do not dominate each other, if i distance = j distance, then generate random number between 0 and 1. If the random number <= 0.5, i selected else, j selected.

    • This implementation oppose against crowded comparison operator, which used rank comparison not dominance comparison, doesn't it?.
    • If rank comparison is not used, why we need sort initial population using fast non-domination sort?

    2. In JMetal implementation, NSGA-II procedure begin from:

    • Generate initial population -> Binary tournament selection -> Recombination -> Mutation -> population combination -> ranking -> ... -> Pareto solution set
    • So, initial population is not sorted using fast non-domination sorting. Fast non-domination sorting is used once in ranking process. It show that fast non-domination sorting is not required for initial population.

    These make me enough confuse about NSGA-II procedure and selection process between the concept and its implementation by Deb and JMetal. Please CMIIW.

  • Rocktim R Das added an answer in Fish Ecology:
    Can anyone please give recent references (if any) of taxonomic keys to the fish family Mugilidae from Eastern or Western Indian Ocean?

    I am working on fish ecology in an Indian estuary. However, proper identification of species belonging to Mugilidae is very difficult particularly of the genus Mugil and Liza. Most of the references available (FAO identification sheets and some Indian keys) differentiate the species based on the premaxillae shape which is difficult to ascertain in juveniles of the family. Also the family is highly dynamic with many new or updated genus and species. So, are there any recent comprehensive taxonomic keys available for the family from the Eastern or Western Indian Ocean regions?

    Rocktim R Das

    Dear Paromita

    The FAO key to the family Mugilidae may be a handy reference for your work:- It is freely available in google though I am still sending you a copy.


    Rocktim R Das

  • Anthony G Gordon added an answer in Dolphins:
    Why do dolphins strand themselves on beaches?

    I haven't found yet any reasonable explanations for this.

    Anthony G Gordon

    "4. Why would barosinusitis in one whale exclude the possibility of similar injuries in 100 diving whales? If the pressure disturbance surrounds the entire pod, all of the diving whales would be injured in the same fashion."

    Traumatic or blast ruptures are idiosyncratic.  If a bomb goes off in a crowded space, human eardrum injuries are quite variable.

    Again, is there any evidence for common-source injuries from external events in groups of human divers, eg in native divers in some parts of the world? 

  • James Byron Nelson added an answer in Perceptual Learning:
    In constant stimulus method, will using feedback and the stimulus interval affect psychometric function?

    In constant stimulus method, will using feedback and the stimulus interval affect psychometric function?

    And another question is, is feedback necessary in pre-test and post-test of perceptual learning?


  • Fabiano Gumier-Costa added an answer in Electronic Waste:
    Does anyone have a contact person at the Bazilian Ministry of Environment (CORI or GTA), concerning negotiations on the e-waste sector agreement?

    My doctoral research is in the area of environmental law, focusing on good regulations for reverse logistics of electronic waste. In addition to analyzing the development of European directives on the matter, I also observe the same process in Brazil, and will possibly suggest some instruments based on the European experience to enhance that process.

    Therefore, a contact with officials at the federal level on this topic is essential, particularly in order to obtain access to specific documentation. It is also urgent, given that none of the previous contact attempts by the means made public have been effective.

    Fabiano Gumier-Costa

    You're welcome!

  • Nadeem Kazmi added an answer in Anopheles:
    Dear colleagues, do you know references about thresholds of annual rainfall and abundance of mosquitoes (Aedes and Anopheles)?

    Dear colleagues,

    I am working in national cartography of dengue and malaria risks in El Salvador using GIS. I am using Hierarchy Analysis Method, and one of the factors that I took into account is annual rainfall. I grouped each subfactor in different weights 1, 2, 3. For example according scientific literature about the relationship of Aedes mosquitoes and temperature: 1- (average temp less than 13 C) - Low mosquitoes activity; 2- (average temp. 13-20 C - moderate activity; 20-33 high activity). I found a lot of references that speaks about the importance of rainfall (linked to humidity conditions) about mosquitoes proliferation, however I didn't found any reference about rainfall thresholds. Could you give me some references please? Thank you very much for your kindly attention.

    Nadeem Kazmi

    Hello Alexander,

    See the link below


  • Ewald Schnug added an answer in Manure:
    How can I measure phosphate from chicken manure water?

    We dissolved the chicken manure in destilled water (10g manure in 200ml destilled water. We whant to know how mutch P contain this water). We are searching for detailed protocol.

    Ewald Schnug

    see attached file!

  • Leodoro Labrague added an answer in Nursing Management:
    Is there an available scale to measure caring behaviors of nurse managers?

    I am currently working on my research about the impact of nurse managers' caring behavior. Can anyone suggest a scale to measure caring in nurse managers?

    Leodoro Labrague

    Yeah i think so caroline!this is exciting. Will work on this and maybe you are interested you join in

  • Subrata Ghosh added an answer in Science 2.0 and Open Access:
    How is ResearchGate dealing with copyright issues when posting our papers?
    I am wondering if there are any copyright issues when we post our published papers on ResearchGate? Is there any rule we should follow or we can simply upload the papers and hope that we do not really break the publisher's copyrights. I will be more than happy to know more about this.
    Subrata Ghosh

    Although uploading the paper in open network like RG is against the copyright issue of publishers, I support the statement made by Dr. Alexandra Elbakyan (the founder of Sci-Hub) that 

    1. “Everyone should have access to knowledge regardless of their income or affiliation. And that’s absolutely legal. Also the idea that knowledge can be a private property of some commercial company sounds absolutely weird to me.”

    2.“All papers on their website are written by researchers, and researchers do not receive money from what Elsevier collects. That is very different from the music or movie industry, where creators receive money from each copy sold,” (in particular this statement)

    + 2 more attachments

  • SOHAIL AHMAD KHAN added an answer in Dilatation:
    Why are dilatant (shear thickening) fluids so uncommon?

    Dilatant fluids seem very useful, but relatively uncommon, when compared with shear-thinning fluids. Why is this so?


    Dilatant fluids are generally used for making protection guard for armored and wearing clothes for safety of vehicles and personnel of army/firefighting personnel/sportsmen. However, these require multi layers of high density/concentration dilatant(40 to 70% solid). This increases weight of wearing clothes or protection layer and dilatant fluid volume requirement is more. Also, this protection will be useful only against high velocity object piercing but will fail to protect against slow piercing. Thus, its use is uncommon. Shear-thinning fluids are used for lubrication and paints and require less volume. Due to wide application, these are more common.

  • Jetty Ramadevi added an answer in Climate Change Impacts:
    How do species respond to climate change? What impact does climate change have on species?

    I address you with two questions again, as they have no meaning if I do separately, so I: How do species respond to climate change? & What impact does climate change have on species? 

    I, based in my experience for long time I think, climate change with feedback loop are moving towards their altars environmental conditions, necessary for species and alters environmental conditions, necessary for life and the development of species, so in near future will have natural habitats, so alters biodiversity, and after that will have species, their extinction or adaptation, which can in turn have an impact with negative and positive effects on climate.


    climate change, with feedback loop & the nature of biological species with their characteristics (behavioural, physiological and genetic) are moving towards their extinction or resilience, so will have adaptation, and after that will have changes in biodiversity, which can in turn have an impact with negative and positive effects on climate.

    Your answers in the form of the debate will help us a lot to know something more in the near future on changes in biodiversity, which then biodiversity will have impacts with negative & positive effects on climate.

    Jetty Ramadevi

    Marcel it is belief of the person, whether spirituality or not. Each and every one has their own opinions about spirituality, India is a secular country. One thing human's power is always less before Nature's. At the most we can take certain actions to minimize the death toll.
    First we have to do our duty then comes God or any Super natural power. My opinion if we struggle hard certainly we get the result. The same applicable to the economic scenario of the country too. If the Leader is capable and takes the proper decisions then only country leads ahead.

  • Carlos Araújo Queiroz added an answer in Ethanol:
    Is n-heptane soluble in ethanol ?

    I wanted to know whether n-heptane is soluble in ethanol and water or not. Can anyone please hepl me with this??

    Carlos Araújo Queiroz

    According to the phase diagram for the system ethanol—n-heptane—water at  25 ºC (*), ethanol is miscible n-heptane at 25 ºC for the whole composition range, but phase separation may possibly occur for n-heptane richer solvent mixtures if water is present, even if at a relatively small amount. 

    (*) J. Phys. Chem. Ref. Data, 28(4) 1999, 983-1235; cf. fig. 15.

  • Esra Gov (Korurer) added an answer in Bioconductor:
    How can I evaluate both and up regulated genes in a microarray data?


    I'm studying about detection of differential expressed genes (DEGs) by using disease vs healthy samples microarray data. I use Limma in Bioconductor for analyze the DEGs. I realize that some of DEGs are both up and down regulated. For example, while ARAP2 gene was upregulated in 2 probe set, this gene down regulated in 3 probe set at one dataset. How is this situation occur in transcriptome level. Is this gene up or else down regulated in real? How are we explain both up and down regulated genes in same dataset?

    Esra Gov (Korurer)

    Thanks Prof. Wilhelm, maybe, I think that gene expression ratio may change depend on disease progression. Could you also think there is possible?

    Tnaks Prof Yuang, I collect data from gene expression omnibus, there are almost 400 sample and 8 different dataset. I detect both up and down regulated genes at all datasets, separately.

    Thanks prof. Saber and Prof. Saini. I consider your purposes.

  • Alexandros Chatgilialoglu added an answer in Spheroplasts:
    How can I increase bacterial outer membrane permeability without killing the cell?

    Dear research community,

    I have met an interesting issue in a small research side project in which I am engineering some bacteria. For this though I would need to permeabilize the outer membrane of E.Coli in order to bring a bigger peptide (5kDa) or protein (72kDa) to the inner membrane. However, the cell should be preferably still alive (able to do gene expression).

    I know that preparing a spheroplast might be one possibility. Does anyone have a good protocol for this? What would be a good control that I know that I have produced spheroplasts?

    Do you have other suggestions then please let me know. :) Thank you...

    Alexandros Chatgilialoglu

    @Felix write me in private at alex.chatgilialoglu@remembrane.com. Thanks

  • João Paulo Orlando asked a question in SWRL:
    Does someone know some ontologies that have more than 100 SWRL rules?

    Someone knows some ontologies that have more than 100 SWRL rules?  I would like to run tests on these ontologies in Ph.D.

    I only know this ontology:


  • Hasan Rosyadi added an answer in IPR:
    Why are geoscientists not applying for patents and are we that generous not to possess our "information wealth" for our own good?

    In the age of open economy and transformation of material wealth to information as  wealth, and the widespread application of IPR, it seems that the geoscientists are not getting their due in terms of number of patents applied/granted when compared with other sciences. It does not mean that we, the geoscientists are not generating enough information or design processes worthy of getting patents. Even the routine academic performance is also being measured in terms of number of patents generated out of academic research!! On the contrary, it seems that the number of patents granted to other sciences is multifold higher than the geosciences. Please share your thoughts on whether we should work on problems worthy of generating patents. I am putting forth this question to get convincing answer and also to spread awareness on the importance of IPR regime in geoscientific research.

    Hasan Rosyadi

    I asked to my Prof about patent. He said knowledge is human right. Patents is like a dark hole for develop knowledge.
    In my opinion for technology and industry is ok.

  • Kangho Lee added an answer in Outliers:
    Which is the best method for removing outliers in a data set?

    In statistically analyzing a data set, suppose we have to found some of the outliers, if necessary to remove them which method is appropriate?

    Kangho Lee

    You had better used exell program and you can find outliers.

    Best regards.

  • Alexander N Titov added an answer in Thermal Properties:
    Any advice to spin polarize or non-spin polarize thermal properties?

    I am trying to obtain transport properties of a half metal material using Boltztrap.  In fact this material have different band structure for every spin.Now for calculating transport properties the spin polarize or non-spin polarize must be implemented?

    Alexander N Titov

    In principle, an electric current in half metal material should be considered as the sum of the spin polarized currents for spin state majority and minority. So if mechanism of scattering depends on the direction of the spin, you should consider separately the current for every spin direction. If such a dependence is not expected that these currents can be summed.

  • Beatrix Chin asked a question in Glycerol:
    How do I remove water from crude glycerol?

    Hi I have some crude glycerol that having 10% of moisture content.How am I suppose to remove the water other than boiling ?

    Thank You 

  • Umar Yusuf Madaki added an answer in Weibull Distribution:
    Where can I get code of CURE FRACTION MODELS with a Bayesian Approach (MCMC) in R OR SAS?

    Actually am working on cure fraction  models i.e MIXTURE AND NON-MIXTURE MODELS BASED ON BETA, WEIBULL AND BETA-WEIBULL DISTRIBUTION, which am considering the RIGHT CENSORED DATA.  

    My objectives are to incorporate the covariates in the models and simulate to obtain the respective posterior summaries. PLEASE ANY ONE TO PROVIDE ME WITH A CODE??? 

    Umar Yusuf Madaki


  • C M Bhatt added an answer in HEC-GeoRAS:
    I am usually confronted by why MIKE is a better flood modelling tool to others. Are there any reliable answers and sources to justify this?

    Hi. I am using MIKE FLOOD software (MIKE 11, 21 and interlinking both in MIKE FLOOD) for riverine flood mapping. I am usually confronted by why MIKE is a better flood modelling tool to others such as caesar-lisflood, HEC-GeoRAS, WaterRIDE FLOOD and the like. Are there any reliable answers and sources to justify this. Thanks

    C M Bhatt

    Model choice is guided by

    1.Kind of output we are looking for; some support 1D and some 1D & 2D.

    2.What type of inputs we have for model to run.

    3. Whether all functionalities of model are useful or some.

    4.What kind of support it offers.

    5.Ease of access and cost-effectiveness.

    All models excel in some or the other MIKE-SWMM-HEC RAS etc

  • Naila Nizamani asked a question in Hierarchical Multiple regression:
    Can the categorical variable (based on which stratum are made) be used as control variables in hierarchical regression?

    I have used stratified sampling in which i have drawn stratum's based 'age' a categorical variable. I am confused whether to use 'age' as a 'control variable' or as a  'independent variable' in hierarchical regression. I am in desperate need for the answer. Technical assistance is highly appreciated. Thanks in prior.