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  • Rhollthan Tubale added an answer in Magnolia:
    What species are these pollen from?

    I have been identifying pollen species gathered from nests of Tetragonula biroi Friese for my undergraduate thesis. I have consulted available printed materials, however, we can't confirm the identity of this minor pollen. I just want to ask if anyone recognizes some of these. I with my adviser identified some possible identities listed below.

    5. Donax canniformis (G.Forst.) K.Schum.
    8. Magnolia kachirachirai (Kaneh. & Yamam.) Dandy (This is present in Taiwan but there is no literature yet confirming its occurrence in the Philippines.)
    9. Uraria lagopodioides DC.
    10. Nothofagus type (N. alpina (Poepp. & Endl.) Oerst. is used as an ornamental here in our country, but I haven't yet seen it flowering.)

    Rhollthan Tubale

    Sir Reza,

    Thank You for that quick response. However, we have already performed the acetolysis procedure before taking these photomicrographs. I was reluctant at first to post this question for the reason that the images might not be enough to properly identify the pollen.

    Thank you again for the response. This will be of big help to reduce the number of unidentified pollen source in the study.


  • Mohamed El Naschie added an answer in Universe:
    Why is there something instead of nothing ?

     LET US START BY WHAT  Robert Adler  WROTE   ON 6 NOVEMBER 2014--:
    People have wrestled with the mystery of why the universe exists for thousands of years. Pretty much every ancient culture came up with its own creation story - most of them leaving the matter in the hands of the gods - and philosophers have written reams on the subject. But science has had little to say about this ultimate question.

    Mohamed El Naschie


  • Charles Bertelsen added an answer in Desert Ecology:
    Are wadi sediments in an arid desert considered a kind of soil?

    Sediments of these wadi are composed mainly of sand 

    Charles Bertelsen

    The importance of these ephemeral systems is discussed in the attached report. It's the best I've read on the subject.

  • Lidia Oliveira asked a question in Portugal:
    What doctoral thesis in communication that have been defended in Portugal between 2005 and 2015?

    We are conducting a survey of the doctoral thesis in communication (2005-2015, in Portugal). If you defended his thesis in the field of communication sending us this information:
    - Name
    - Thesis title
    - Defense Year
    - Keywords
    - Advisor
    - Names and institutions of the jury members
    - The thesis (or link to the thesis)

  • A. Subba Rao added an answer in Soil Chemistry:
    When soil solution is concentrated four times, will K-Ca activity ratio in solution change?

    As we know that activity ratio is K /Ca or K /Ca+Mg  is influences soil solution.

    A. Subba Rao

    Dr.Manikandan,please read the following publications to better appreciate the concept of activity Ratio and Ratio law.Soil Conditions and Plant growth by Russell, Wiley Black well or revised edition. You may also read short 2-3 page brief description in Encyclopedia of Soil Science http://books.google.co.in/books 

  • Carlos Bolaños Carriel asked a question in RID:
    Why fermentative pathways are used instead of anaerobic respiration to get rid of the NADH+H?

    Fermentative pathways are those where NADH+H+ is reoxydized by their metabolic products. Why using fermentation instead of anaerobic respiration? It seems that anaerobic respiration is more efficient for the same process.

  • Russell Hopfenberg added an answer in Philosophy Of Science:
    What are the best references in fictional literature to teach Philosophy of Science?

    I intend to use classical books and stories to explore conceptual topics on Philosophy of Sciences. Can anyone suggest some references?

    Russell Hopfenberg

    Ishmael by Daniel Quinn is an easy read - 7th or 8th grade level, but used in many graduate courses.  The book addresses global sustainability issues.  In it, "the teacher" elucidates our "cultural mythology" (analogous to bias in science) as interfering with an accurate interpretation of clear scientific evidence.  This book challenges our worldview.  Think of the way our cultural worldview has been, and continues to be challenged by the theory of evolution.  You'll enjoy this book.

  • Lidia Oliveira asked a question in ICT:
    Does anyone known studies about the social use of time?

    I'm interested in studies that relate the use of ICT and the social use of time

  • Karen Green added an answer in Modeling and Docking:
    Dose anyone know peptide PDB coordinates generator (programs or codes)?
    I have some peptide sequences and I want to get the pdb coordinates file of these sequences. Actually I don't care if the stuctures are folding correctly, I just want to get a pdb file first, just a random coordinates will be OK. Does anyone know any program could do that or have a code can generate a proteins ' PDB coordinates file acoording the sequence?
    Karen Green

    Discovery Studio Visualizer from Biovia/Accelrys is the free version of their DSV product and it allows you to build canonical helices, etc from sequence amino acids.

  • Lidia Oliveira added an answer in Internet Use:
    Does anyone know studies investigating the relationship between Internet use and loneliness?

    There is a relationship between the increase in the number of hours of Internet use and the increased perception of loneliness?

    Lidia Oliveira

    Good mornig
    Thank you for your help.


  • Ran mo asked a question in Alpha:
    How to detect HIF1 alpha level inside growing tumor?


    Is there any method for detecting HIF1 alpha expression level?

  • Lidia Oliveira added an answer in Humanities:
    Im interested in publishing in International Journals about Literature with good reputation. Do you know some of them?

    I would like to know open sources to publish in International Journals about Literature or Humanities. With good reputation and from best Universities. 

    Lidia Oliveira

    Hi Sara

    you can see in: http://www.scimagojr.com/journalrank.php?area=1200&category=1208&country=all&year=2014&order=sjr&min=0&min_type=cd

    The main categorie is "Arts and Humanities" and de sub-categorie is Literature.

    Good work and good luck.


  • Rafik Karaman added an answer in Molecular Biological Techniques:
    How do I extract DNA from Human Placenta for analysis of PMS2 gene?

    I have never worked with human placenta before and now as my final year dissertation that is that type of sample that is going to be provided. I also have to do a business plan but I cannot find anywhere how much would cost me to get a sample of human placenta. Any help? Also what are the best kits ?


    Rafik Karaman

    Dear Sofia,

    The following papers cover the answer to your question. For viewing the full paper please use the following link:


    1-Cell Research (2005) 15, 539–547. doi:10.1038/sj.cr.7290323

    Mesenchymal stem cells derived from human placenta suppress allogeneic umbilical cord blood lymphocyte proliferation
    Chang Dong LI1, Wei Yuan ZHANG1, He Lian LI2, Xiao Xia JIANG3, Yi ZHANG3, Pei Hsien TANG3 and Ning MAO3

    Human placenta-derived mononuclear cells (MNC) were isolated by a Percoll density gradient and cultured in mesenchymal stem cell (MSC) maintenance medium. The homogenous layer of adherent cells exhibited a typical fibroblast-like morphology, a large expansive potential, and cell cycle characteristics including a subset of quiescent cells. In vitrodifferentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic, osteogenic and chondrogenic lineages. Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was a homogeneous cell population devoid of hematopoietic cells, which uniformly expressed CD29, CD44, CD73, CD105, CD166, laminin, fibronectin and vimentin while being negative for expression of CD31, CD34, CD45 and -smooth muscle actin. Most importantly, immuno-phenotypic analyses demonstrated that these cells expressed class I major histocompatibility complex (MHC-I), but they did not express MHC-II molecules. Additionally these cells could suppress umbilical cord blood (UCB) lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli. This strongly implies that they may have potential application in allograft transplantation. Since placenta and UCB are homogeneous, the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells (HSC) from UCB to reduce the potential graft-versus-host disease (GVHD) in recipients.

    mesenchymal stem cells, human placenta, umbilical cord blood, immune regulation

    2- Simultaneous isolation of high-quality DNA, RNA, miRNA and proteins from tissues for genomic applications


    Samuel Peña-Llopis & James Brugarolas
    AffiliationsContributionsCorresponding authors
    Nature Protocols 8, 2240–2255 (2013) doi:10.1038/nprot.2013.141
    Published online 17 October 2013

    Accession codes•
    Author information
    Genomic technologies have revolutionized our understanding of complex Mendelian diseases and cancer. Solid tumors present several challenges for genomic analyses, such as tumor heterogeneity and tumor contamination with surrounding stroma and infiltrating lymphocytes. We developed a protocol to (i) select tissues of high cellular purity on the basis of histological analyses of immediately flanking sections and (ii) simultaneously extract genomic DNA (gDNA), mRNA, noncoding RNA (ncRNA; enriched in miRNA) and protein from the same tissues. After tissue selection, about 12–16 extractions of DNA, RNA or protein can be obtained per day. Compared with other similar approaches, this fast and reliable methodology allowed us to identify mutations in tumors with remarkable sensitivity and to perform integrative analyses of whole-genome and exome data sets, DNA copy numbers (by single-nucleotide polymorphism (SNP) arrays), gene expression data (by transcriptome profiling and quantitative PCR (qPCR)) and protein levels (by western blotting and immunohistochemical analysis) from the same samples. Although we focused on renal cell carcinoma, this protocol may be adapted with minor changes to any human or animal tissue to obtain high-quality and high-yield nucleic acids and proteins.

    For placenta guidelines check out:
    Burton GJ, Sebire NJ, Myatt L, Tannetta D, Wang YL, Sadovsky Y, Staff AC,
    Redman CW. Optimising sample collection for placental research. Placenta. 2014
    Jan;35(1):9-22. doi: 10.1016/j.placenta.2013.11.005. Epub 2013 Nov 19. Erratum
    in: Placenta. 2014 Apr;35(4):289. PubMed PMID: 24290528.

    There are number of kits available for simultaneous isolation of DNA, RNA and Protein from cell lines or fresh tissue.  Here is one protocol from Nature http://www.nature.com/nprot/journal/v8/n11/full/nprot.2013.141.html

    There are private companies like Sigma, QiaGen and few others, who also sell these reagent kits.

    Hoping this will be helpful,


  • Ali Reza Amiri Asfarjani asked a question in Fatigue:
    Do you know about Doual phases Iron Fatigue?

    high cycle fatigue

  • Erkki J. Brändas added an answer in Cognitive Systems:
    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.

    Erkki J. Brändas


    It is difficult to see exactly where in your depiction of the retinoid model the step or steps that correspond to the hard problem emerge. In a way it reminds me of Gerald Edelman’s brain based dynamics, i.e. jumping directly to brain based theories seemingly avoiding the hard problem.

    For a physicist like Penrose the step is clearly associated with the brain’s physiological action, i.e. the step from “appropriate physical interaction” to the brain evoking awareness. For Terrence Deacon, mentioned earlier both by me and recently by Louis that “the self” is some kind of Gödelian absentia providing what he calls ententional phenomena. The latter is a complex concept to digest, but it makes sense in my so-called Correlated Dissipative Ensemble.

    Would it make sense to relate the hard problem to the all-inclusive mathematical space of correlations as they become projected onto our 4D reality?

  • Bassam Alkotaini added an answer in Enzyme Activity Assay:
    How do I calculate Kcat from Vmax and molecular weight of the enzyme?

    Here is the case,

    Enzyme (D) has Vmax value equals 813.7 U/mg, Km=3.9 mg/ml. Molecular weight 62 kDa. 

    The amount of enzyme used to determine these kinetics is 5 ug in 1 mL reaction volume. 

    I believed that i can do it as:

    (Vmax/0.01612)/60 = 840 1/S. 

    0.01612 was obtained by dividing 1/62; as 62 is the molecular weight in kDa.

    But when I refer to a few papers, I figure out that theis calculation misses something !! 

    Bassam Alkotaini

    Thanks a lot Mr. Shapiro and Mr. Solano

    I actually obtained similar results for an engineered enzyme (catalytic domain + CBM, MW 62kDa) compared to only the catalytic domain only  32 kDa. 

    In the attached file, the previous research group has expressed agarase enzyme extracellularly where the enzyme lost both the signal peptide and its CBM prior to secretion in the culture broth resulting in a catalytic domain only with 32 kDa. They determined the Vmax = 517 U/mg, and Kcat/Km 390 1/(mg/ml) 1/S, in which if you calculate their Kcat according to 32 kDa you will find 275 1/S. However, i can not figure out why do they report it 390 1/S. 

    On the other side and speaking of calculating Km in mM instead of mg/ml, I have noticed few examples for converting it by dividing by 10 like the other attached article 42 mg/ml using agarose as a substrate (i guess MW 120000Da), and 4.2 mM. Other articles reported similar conversion results. Attached file, named Km 42mgml to 4.2mM shows similar calculations. Any suggestions why does it calculated this way? 

    + 1 more attachment

  • Maryam Al asked a question in Plant Pathology:
    What is jornal do you follow in plant pathology field?

    what is jornal do you follow in plant pathology field? , and what is the best journal for publish paper ?

  • Mark E Gould added an answer in Intelligence:
    In your opinion, which variables influence students' motivation?

    I am working on the development of a workshop designed to teachers about how to motivate students to study. Implicit theories of intelligence is, undoubtedly, an important topic to discuss with them! In your opinion, which variables influence motivation towards study?

    Mark E Gould

    While it is true that there is a myriad of complexities in motivation, they do seem to boil down to Ryan and Deci's triad of : competence (mindset, efficacy), autonomy (control) and relatedness (perceived value). To my mind the value component is paramount. The others do not come into play until the value is accepted. At high school, not all students immediately accept the value of education. When students accept this they are easy to teach, when they don't, you have to work hard on your relationship with the student to try to create the sense of value. Once value at any level is accepted, the other two components can be manipulated to maximise motivation. These components are evident in David's post. In general in higher education, students probably have an innate sense of value of their education and hence the other two factors become more important .

  • Francisco T Tirol added an answer in Fibroid:
    What are Phantom Tumors of the Abdomen?

    Since 1838 physicians have described it in London, England . The term was attributed to Dr. Gill who coined the term in 1858.  In physical diagnosis class in the 1950's in Manila, Philippines, we were advised that when an abdominal mass was felt, the differential diagnoses could include the Seven "F's": namely; Fat, Feces. Fetus, Flatus, Fluid, Fibroid. and "Phantom Tumor".  So, what is a phantom tumor? 

    Francisco T Tirol

    Gossipium is latin for cotton. A "gossipiboma" refers to a  foregin body left inside  the abdomen after  laparotomy specifically a  cotton sponge but "recently"  used loosely for any foreign body inadvertently left inside the body cavity.

  • James Garry added an answer in Automobile Engineering:
    WHat is the relation between the Hydrogen volume(or weight) and its tank weight for automobile applications ?

    hello dear colleagues,

    i want to know is there any relation between thé Hydrogen volume(or weight) and its tank weight for automobile applications ?

    many thanks

    James Garry

    Bendjedia ,

    I would have at least two two tanks:


    Each holds 1kg of hydrogen at 350bar.

    You're on the right track, perhaps using three composite tanks.

  • A. Subba Rao added an answer in Plant-Soil Nutrient Interactions:
    What are the changes in the mechanism of nutrients in soil such as C, N, P, K, Ca and Mg ? Do you have any publication that explain this?

    What are the changes in the mechanism of nutrients in soil such as C, N, P, K, Ca and Mg ? Do you have any publication that explain this?

    A. Subba Rao

    Carbon ,nitrogen, phosphorus, and sulphur behaviour and transformations are linked with soil organic matter. Carbon ,nitrogen phosphorus and sulphur cycles operate in soil -plant-animal/human-atmosphere system.Organic matter decomposition and mineralization reactions are important for availability of these nutrients to plants.Adsorption-desorption and precipitation- dissolution are important reactions for phosphorus in soil. Sulphur is adsorbed or desorbed in soils having pH<5.0.Sulphur as SO4 participates in precipitation and dissolution reactions especially with divalent and trivalent cations.Ca,Mg and K  availability is mostly governed by cation exchange reactions. They also participate in precipitation and solubilization reactions.The book mentioned  above is an important publication .You may also refer to Soil Fertility and Fertilizers  byTisdale, S.L.,Nelson,W.L. and Beaton J.D.1985 or latest edition.

  • Azzam K Almosallami added an answer in Gravitational Field:
    Is the non locality of the gravitational field energy a serious problem for General Relativity (GRT)?



    "Although there is no room for such a thing in the energy–

    momentum tensor T, it is clear that there are situations where a ‘disembodied’

    gravitational energy is actually playing a physical role.

    Imagine  two massive bodies (planets, say). If they are close together (and we can

    suppose that they are instantaneously at rest relative to each other), then

    there will be a (negative) gravitational potential energy contribution which

    makes the total energy, and therefore the total mass, smaller than it would

    be if they are far apart.  Ignoring much tinier energy effects,

    such as distortions of each body’s shape due to the gravitational tidal field

    of the other, we see that the total contributions from the actual energy–

    momentum tensor T will be the same whether the two bodies are close

    together or far apart. Yet, the total mass/energy will differ in the two cases,

    and this difference would be attributed to the energy in the gravitational

    field itself (in fact a negative contribution, that is more sizeable when the

    bodies are close than when they are far apart)." 


    The same problem was also rised by Thirring, Kalman and Feynman in the FGT theory, they inserted the gravitational energy in the tensor equations...

    It is a problem of paramount importance which prevents the General relativity theory from describing any motion in which the hamiltonian is time dependent or rather in case of non isolated systems, or in case of non stationary interactions between different bodies.

    The attempt to model a free falling body in a gravitational field for GRT seems impossible.

    GRT has been tested  only for static or stationary systems where there is not a net exchange of energy (excluding gravitational radiation)

    Don't we need another GRAVITATIONAL THEORY which includes the results give by GRT in order to explain with a better accuracy the simple phenomenon like the free falling of a mass in a gravitational field?

    Azzam K Almosallami

    Stam Nicolis,

    None can understand the value of this paper more than me, it is a same  copy of my ideas in part 2 of  my paper in http://vixra.org/abs/1509.0059 and before in http://gsjournal.net/Science-Journals/%7B$cat_name%7D/View/2310

    I understand well how the author will face the violation of Lorentz invariance in case of adopting the continuity and objectivity same as in classical physics, same what happened with me before. Because of that I asked you again and again who told you Lorentz transformation is a real transformation can describe the motion of objects. Now again we back to the fake reciprocity principle in SRT and the London-Paris problem.

    According to the discontinuity and the uncertainty principle in my transformation and my equivalence principle, zero point energy can explain   the rotation curve of a typical spiral galaxy: the 'flat' appearance of the velocity curve out to a large radius. While according to continuity and objectivity which is adopted by relativity, MOND theory proposes a new constant acceleration without any physical meaning for this new acceleration, so, what is the difference between the Zero point energy in quantum and this proposed new acceleration by MOND theory. Furthermore, Mercury precession, light bending by gravity, Shiparo delay, and the Pioneer anomaly can be explained by the uncertainty principle.

    After all, now all should understand, why it is impossible under objectivity and continuity same as in classical physic,  gravity will be unified with quantum...no way!!! Because no way to explain the anomalies of gravity without the uncertainty principle in quantum. In fact all the anomalies of gravity are resulted as a result of the uncertainty principle in quantum. How physicists will know that, while they are keeping on objectivity and continuity in macro, which they are really fake.

  • Jorge Morales Pedraza added an answer in Financial Support:
    Which are the methods of Government financial support for SMEs?

    Especially,  the method of finances with grants. 

    Jorge Morales Pedraza

    You can find good informtion on this subject in the link: https://www.gov.uk/government/.../bis-13-p176b-sme-a.

  • Rahmat Imam Prabowo asked a question in Chemical Analysis:
    Are there any correlation between nitrogen, potassium and phosphate concentration in plant tissue?

    I want to estimate the concentration of potassium and phosphate in plant tissue with non destructive method or using nitrogen content as base of independent variabel in mathematic modeling so I don't need to used chemical analysis.

  • Damon Farias added an answer in Nano Research:
    How to search data of xrd from JCPDS number?
    I want to know how to search data if I know JCPDS number.
    Example I knew my JCDPS number it's JCDPS #800075.
    I want to use data with my XRD research graph.
    Damon Farias

    alguém pode me enviar o JCPDS Card 35-0810 (CdSiO3)

  • David Farringdon Spencer added an answer in Formaldehyde:
    How can I shear RNA from formaldehyde-fixed cell lysates with Covaris M220?

    I'm having some trouble obtaining an RNA 200-500 base fragment size in lysates from cells fixed with 1% formaldehyde. I've based the parameteres of my protocol on the Covaris protocol for Total RNA in 130 ul snap tubes (attached), however, this protocol is for pure, unfixed RNA. With all the parameters the same, I've increased treatment time up to 30 minutes, but I am still getting average fragment sizes far beyond 1000 bases. Which parameters would be best to vary to obtain the desired size?


  • Khodijah Alatas added an answer in Propolis:
    Can I record optical density of A. actinomycetemcomitans with Od450?

    I'm now evaluating antibacterial effects of propolis on A. actinomycetemcomitans. Thank you. If you have or know some resources that I can use Od450 it will be very helpful. Thanks 

    Khodijah Alatas

    Dear, Ms Ferdes.

    Do you have any journal or resources for the formula you gave to me? I really need it for my thesis. Thank you so much :)

  • Amallah Lamiae asked a question in Durum Wheat:
    Reviwers of agronomy and genetic evolution in french please?


    Can anyone be a reviwer of my manuscript in french?I need 2 reviewers please, the subject of my paper is abbout the genetic diversity of durum wheat.

  • C. Lewis Kausel added an answer in Fluctuations:
    Could you please tell your point of view on the current situation worldwide ?

    Is it a stable or fluctuating and we are faced to the glabal danger

  • Janet Hanson added an answer in Multicultural Education:
    What summary resources are available to identify the state requirements for teacher certification in the area of multicultural education in the US?

    I am researching the various state requirements for the teacher certification in the area of multicultural education including; ELL, ESOL and equity in inclusion for diverse populations. If you have any information such as open data bases, recent meta analysis research articles or the names of individuals at agencies that have information on the number of teachers certified for ELL, number of students identified as ELL by state and requirements by state for certification in these areas (in additional or separate certifications) I would be greatly appreciative. The goal is to develop and improve our course offerings and education requirements for Class 7 multicultural teacher certification in our state.

    Janet Hanson


    Thank you for your courtesy in replying! I am grateful for your response. I wish you the best in your future studies.

    Kind regards,