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  • Haikai Tane added an answer in Social Theory:
    What stories of how complex adaptive systems "work" have you encountered?

    I have identified some 50 CAS concepts commonly used by authors in the paper.  They range from those derived thru chaos theory and agent-based modeling, to self-organization of agents as they interact and co-adapt, to emergence, etc. I have created one brief story that weaves together clusters of these concepts and then another brief story that weaves together the clusters.

    How important is it to have a coherent story as one applies the concepts to new areas of inquiry?  Is a universal story across domains necessary?  What is it?

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: The study surveys 25 popular secondary sources (1992-2014) on complexity theory and complex adaptive systems (CAS) to develop a comprehensive framework of CAS attributes used when authors reference CAS theory. The attributes are analyzed using network analysis algorithms to determine if there are related clusters of concepts. A two level story of theoretical relationships is developed between the attributes within the clusters and between the clusters to augment the CAS Framework. The complete CAS Framework is used to map CAS theory representations from the sources so that comparisons and evaluations of focus and thoroughness can be easily made. The result is a tool that can be used to assess any representation of CAS theory in any context, but especially in the social sciences with human agents.
      Full-text · Article · Dec 2014
    Haikai Tane

    I would be interested in your comments on how my colleagues and I are addressing the closed/open system dichotomy...We have discussed this in trans-Tasman dialogues since the early 1990's ~ in an attempt to achieve common terms and understandings of them ....

    My brief summary of system attributes and scientific models (best representing their processes and outcomes) is deliberately short and simple: assuming scientific rigeur is best achieved by precise terminology.

    1. Open systems import matter and energy ~ closed systems can only import energy

    2. Closed systems can be viewed as operating through sequential temporal processes amenable to (a) linear logic with fixed time  (b) cause and effect analysis and (c) statistical analysis NB Assumption: Time is the fixed constant!

    3. Open systems integrate spiral helix and circular processes geospatially ~ amenable to (a) mapping and modelling, (b) symbolic logic, (c) monte carlo simulations and (d) learning-by-doing experiments (real time gaming simulations eg Watershed pGiS) NB Assumption: Space is the fixed constant! Time is variable ....

    4. Closed systems are scientific models readily amenable to alpha-numeric analyses ~ with potential to forecast or predict future states of the system at set times and defined levels of probability (using alpha-numerics)

    5. Open systems are scientific models readily amenable to spatial simulations ~ with potential to map and model their behaviour and outcomes (using true imagery, remote sensing and geospatial intelligence systems)

    6. The scientific methods applicable to closed and open systems are not alternative choices ~ nor are they interchangeable.

  • Subhadip Das added an answer in Immunofluorescence Staining:
    Are there other methods to detect primary cilia on the cell surface besides using immunofluorescence staining? Could flow cytometry be used?

    I am trying to concomitantly assess what phase of the cell cycle  ciliated cells arrest in upon drug treatment.

    Subhadip Das

    Flowcytometry is the best way to determine the cell cycle u may use PI or 7AAD with the specific cell cycle regulatory protein. Advantage is you may monitor also changes the cellular granularity by this method upon your drug treatment. 

  • Vijay Siva added an answer in Visible Light Communications:
    There is a heading states Li-fi vs VLC in the pdf i had attached. Whether Light-fidelity and visible light communication are same ?

    I am doing my academic project in Light-fidelity whether Light fidelity and visible light communication are same things or do they differ in principle.

    There is a heading states  Li-fi vs VLC in the pdf i had attached

    Frequently  Light fidelity and Visible light communication(Vlc) are used as alternative terms in optical communication.

    I am trying to write a survey on light-fidelity can i use the papers of visible light communication for the survey are they similar or different. Because if have only few standard  journal reference data  on Light fidelity .

    Vijay Siva

    Thanks Albert manfredi  for your valid response. I had read those lines I had question due to the following statements


    Li-Fi is a term often used to describe high speed VLC in application scenarios where Wi-Fi might also be used. source.


    Lifi is a form of  visible light communication

  • Pepe Arellano asked a question in Public Space:
    Can anyone refer some text about the problems of management of public spaces where different levels and branches of government are involved?

    There are too many studies about how to improve the public space, but what happens when there are too many governmental actors working without coordination, plans or goals? Thanks for your help!

  • Silburn Clarke added an answer in Oil:
    Does the downward trend in energy costs portend any unique and sustainable competitive advantages for oil-consuming developing economies ?

    As costs for energy has trended downwards some observers have declared and projected special competitive advantages for a number of oil consuming developing nations.  But is this true ?  Or is it the cse that as all countries derive the common benefits then none will be occupying a uniquely advantageous position

    Silburn Clarke

    Agreed Juan / Boye,

    Unless the beneficial window afforded by the lowered prices for oil-consuming economies is used in create a differential advantage, then these economies will not enjoy any special advantage vis-à-vis their international rivals

  • Magdalena Podkowik added an answer in Science Communication:
    Will increaseing template DNA in real time PCR improve its efficiency?

    Will increasing my DNA template increase the efficiency of the PCR reaction? I have currently got 10 ng of template in my reaction mix. My boss has asked me to try adding 50 ng of template to increase the reaction efficiency? Any feedback from the science community?

    Magdalena Podkowik

    Amount of template is one of the factors that can influence efficiency of your PCR reaction. My answer is: not necessarily-more does not always mean better. Remember that your DNA/RNA preparation always contains some protein and salt contaminations that may inhibit polymerase activity. Its robustness is also restricted. Check precisely cycling conditions adequate for your enzyme, cycler(!) and primers Tm. 

    And finally plot the efficiency curves by running serial dilutions of your samples at different temp. Even if you don't know the equation your qPCR software will do it for you.

    Hope it will help!

  • Kunal Mondal added an answer in Carbon:
    Mesoporous carbon

    Does anyone here know if mesoporous carbon under the following intrinsic characteristics is obtainable:

    - Specific surface > 3'000 m2 per gram

    - Variable pore size: 2 to 50 nanometers

    An idea on price per ton would be welcome as well.


    Laurent H. Selles

    Kunal Mondal

    By definition, it is a mesoporous but, that much high surface area is possible by presence of micropores. There is a possibility that in your  samples, the mesopores are connected to micropores. 

    Best wishes,


  • Linda L. López asked a question in Academic:
    After analyzing all of aspects focused on reliability on research, what kind of parameters should be considered in order to validate a sample?

    After talking with some new researchers, it has been evident that they had a deep inquisitiveness about how to validate a research focus on the size of sample. What kind of Academic parameters should be taken into account for considering a research within a high Academic level ? Thanks for your kind attention.

  • Yuan-Yeu Yau added an answer in Plant Tissue Culture:
    Advantages and disadvantages of Horizontal Vs Vertical laminar flow cabinets?

    Which type is more suitable for Plant tissue culture?

    Yuan-Yeu Yau

    Hi Mahasen,

    1. Here on this website below, it lists some criteria in how to choose a laminar flow-- a horizontal or vertical laminar flow.  It also lists the pros and cons of using them. It mentions a few good points.


    2. I have used both of them, but I prefer horizontal one myself. The only things with concern is that the air is directly blown into your face. So, the eyes can be a little bid dry if one works for a few hours a day in it (such as for a tissue-culture lab). Wear glasses is one way to make eyes feel better. If you use flame (70% ethanol) to sterilize your forceps, the flame can be blown towards your hands, so need to be careful.

  • Kenneth M Towe added an answer in Environmental Change:
    How to quantitatively distinguish the human and natural caused marine environemtal change? Is there any appropriate proxies?

    I want to study the environmental change of a coastal bay through sediment records, is there any appropriate proxies to  quantitatively distinguish the human and natural caused marine environmental change?

  • Holger Wille added an answer in Enzymes:
    In enzyme assays, what is more important to keep fresh either enzyme or substrate?

    In my case i am trying to monitor different crude enzyme activities for every 24 hours. i know the importance of substrate which should be freshly prepared since most of the substrate are readily oxidizable. But bit costly. Coming to enzyme part, their storage with time decreases their efficiency. So please suggest me some answer. Thanks in advance.

    Holger Wille

    Some enzymes can be stored at -80oC for quite a while, others degrade noticeably and need to be stored at liquid nitrogen temperatures instead.

    Crude enzyme preparations can be more tricky, since they may contain many other components which could be harmful to your enzyme (e.g. proteases, inhibitors, etc.).

    If you have access to liquid nitrogen storage, you can also store your substrate at that temperature and expect a longer shelf / half life.

  • Abdellatif Benraiss added an answer in Fluorescence Imaging:
    Does anyone have good landmarks for cyrosectioning the rat brain for substantia nigra/ VTA sections?

    I need coronal sections of the substania nigra and VTA for confocal fluorescent imaging. When cutting in the brain on the cryostat, what are some useful landmarks I can use (looking grossly) to know I have the right sections. The Paxinos atlas isn't very helpful.

    Abdellatif Benraiss

    Didi you try the Allen brain atlas?


  • Syed A Ali added an answer in THP-1:
    Do you have some experience with cultivation THP-1 in IMDM?

    I know, that the best choice for this is RPMI-1640 but I need to prepare co-cultivation experiments with cells line of renal epithelial cells. In our protocol I use IMDM for cells of renal epithelium. When I added IMDM to THP-1, they adhered. Is it normal? Thanks for you help!

    Syed A Ali

    Yes, it is possible that your medium was contaminated. THP-1 monocytes do get activated by LPS. However, I did not know they get activated in absence of visible microbial contamination. Nevertheless, I am glad to hear that your problem is solved.

  • Albert Manfredi added an answer in Home Science:
    How can Gravitational Waves Detection is going to benefit our society?

    Recently, Gravitational waves detection have been observed by scientists which was predicted by Albert Einstein in year 1916. Now, the real question is, how can it going to benefit our society?






    Albert Manfredi

    The warp drive!

    Find a way to move through the squeezed parts of space, in sync with a gravitational wave, to effectively move faster than your linear speed suggests. Has to be synchronized somehow, to avoid cancelling out the effect when traveling through the stretched portions. And you need something substantial, so gravitational wave amps are required.

    Or communications. Modulate gravitational waves for speed of light comms through any object.

    After all, it's likely people were wondering what the big deal was about E&M, when EM waves were first discovered in the 19th century. And today, we wouldn't know what to do without manipulating these wonderful EM waves.

    (Okay, okay, spare the down votes please!)

  • Peter H. Diaz added an answer in Cestoda:
    Is it unknown freshwater tapeworm ?

    Found this specimen of about 3 cm long and 5 mm width along a freshwater brook in the province of Limburg, The Netherlands. I have seen millions of freshwater invertebrates from our country and I consider myself a specialist on annelids (leeches, oligo- and polychaetes) but I don't thing it is either of them. The only thing I can think of is some sort of (free living?) tapeworm. As it is collected with a pondnet, it is not sure if this is truly aquatic. It is flattened and gradually becoming smaller towards the end or head? Is it decapitated? Does anybody has an idea? many thanks

    + 1 more attachment

    Peter H. Diaz

    Ton that is a neat find, and out of my wheelhouse.  I have passed it along to a colleague to see if he has any answers.

  • Annangi Subba Rao added an answer in Soil Carbon:
    What is the fate of soil organic carbon with crop residues incorporation in tropical and sub-tropical environments?

    Tropical and sub-tropical regions- higher temperatures, rate of OC degradation faster

    Residue incorporation- provides benefit to the current ongoing crop, may be next crop in rotation???

    question of carbon sequestration in root zone profile???

    short and long term consequences of zero/minimum tillage???

    Annangi Subba Rao

    Dear Dr.Pal,as we are  all aware, information on carbon concentration or carbon stocks is needed for getting an idea of soil fertility, soil health and carbon sequestration from climate change point of view.The carbon data we have is scattered in different institutes and organizations. Do you think that there is a new need for data centers or data bank at National level to serve the cause/purpose of various agencies and also for research and modelling purposes?Of course it needs  a lot of programming to accommodate diverse and scattered data.Guidelines  also need to be worked out  for a common protocol to sample ,analyze and report carbon data.

  • Krzysztof Beć added an answer in Gaussian:
    Anharmonic Raman Intensities in Gaussian 09W Revision A.02?

    I wish to compute anharmonic Raman intensities in Gaussian 09W Revision A.02. I have computed the anharmonic IR frequencies which can be found in the output file.

    How do I set up the input file to compute the Raman intensities using the anharmonic frequencies and force constants found in the checkpoint file? (I think I have to use Polar =Raman?)

    Can anyone help with the Gaussian input file script to allow this? Would be much appreciated!

  • Jialei Zhang asked a question in Kinematics:
    Who can tell me the failure rate of mechanical components?

    I know there is failure rate charts  of electrical components. Now I am analyzing the numerical problems of the transient probability of one mechanical system, who knows the failure rate of kinematic pairs like the universal Joint, the prismatic joint, the spherical joint etc.? Thanks!!

  • Abdellatif Benraiss added an answer in Viral RNA:
    During lentivirus packaging, how much of a fluorescent insert is expressed from the viral LTR vs. insert promoter (e.g. CMV)?

    Hi all,

    I'm currently packaging a lentivirus with a large, fluorescently-tagged insert.  My gene of interest (GOI) + fluorescent tag is downstream of a tight tetracycline-regulated CMV promoter.  

    When packaging a lentivirus in HEK293T cells, fluorescent inserts can usually be observed 12-16 hours after transfection of the expression/packaging/envelope proteins in my hands. These are usually downstream of "normal" CMV promoters, and not variants that require transactivation.  

    Viral RNA is also being transcribed from the LTR on the expression plasmid, and the viral genome will contain the same ORF encoding my GOI + fluorescent protein.

    In my current packaging cells, I'm observing no/low fluorescence.

    So how much of the fluorescence observed in my cells post-transfection is expected from the transfected plasmid (driven by CMV) vs. expression from the transcribed viral RNA (driven by the LTR)?

    I am curious because the tet-regulated CMV should not express much in the packaging cells, but translation from LTR-driven viral RNA would be unaffected.  Hence, any fluorescence would be due to the viral RNA.


    Abdellatif Benraiss


    This is all normal. If your expression cassette involves any florescent protein under any promoter (TET inducible or tissue specific promoter) you should see  some fluorescence. The reason is that lentivirus is it self driven by strong promoter to express the RNA.  That is,  the packaged viral RNA span from 5'LTR to 3'LTR and since there is no promoter in LTR (BTW, the promoter which in the 3'LTR has been removed for safety reason since the first generation of lentivirus) a secondary promoter upstream 5'LTR is required for the expression of the viral RNA. Some RNA do not make it to the cell membrane to be packaged,  it's translated to protein like any other RNA. Thus the fluorescence you're seeing! I hope this help.


  • Syed A Ali added an answer in Magnetic Beads:
    Magnetic beads or affinity resin for purification of IgG?

    Which technique is more preferable among magnetic beads and affinity resin?

    Are there pros and cons for each technique?

    Syed A Ali

    Hello J.J.,

    Sometimes I find it faster and more convenient to connect the columns (HiTrap Protein G HP) to a multi-channel peristaltic pump compared to FPLC. I purify up to 4 antibodies in a row.

  • Amer Beltayib added an answer in Patch Antenna:
    Can anyone help with designing substrate integrated waveguide (SIW) technology?

    It is basically a method of excitation for planar patch antenna, but I want to know the mechanism or principle behind this technique.

    If somebody worked on it, please give me the right suggestions to design the same.

    Amer Beltayib

    could anyone help with why SIW  support just TE mode

  • Hala Hazzaa added an answer in Immunology:
    How can I feed mice models with Lactobacillus casei?

    How can I prepare the fermented food by L. casei?

    Hala Hazzaa

    Hi dear,  hope you be satisfied with the selected attachments

    • [Show abstract] [Hide abstract]
      ABSTRACT: Monitoring the populations of probiotic strains of the species Lactobacillus casei in food is required by food industries in order to assure that a minimum concentration of these organisms will be ingested by consumers. In this context, Petrifilm™ AC plates can be used along with selective culture media to allow the enumeration of specific groups of lactic acid bacteria. The present study aimed to assess chemical substances as selective agents for Lb. casei in order to propose a selective culture medium to be used with Petrifilm™ AC plates as an alternative protocol for the enumeration of probiotic strains of this species in fermented milk. Twenty-six probiotic and starter cultures (including six strains of Lb. casei) were plated on de Man Rogosa and Sharpe (MRS) agar with distinct concentrations of nalidixic acid, bile, lithium chloride, metronidazole, sodium propionate, and vancomycin. Vancomycin at 10 mg/L demonstrated selective activity for Lb. casei. In addition, 2,3,5-triphenyltetrazolium chlorine was identified as a compound that did not inhibit Lb. casei, and Petrifilm™ AC plates used with MRS and vancomycin at 10 mg/L (MRS-V) demonstrated more colonies of this organism when incubated under anaerobic conditions than aerobic conditions. Acidophilus milk and yoghurt were prepared, added to Lb. casei strains, and stored at 4 °C. Lb. casei populations were monitored using MRS-V and MRTLV by conventional plating and associated with Petrifilm™ AC plates. All correlation indices between counts obtained by conventional plating and Petrifilm™ AC were significant (p < 0.05), but the best performance was observed for growth on MRS-V. The obtained data indicate the efficiency of using MRS-V associated with Petrifilm™ AC plates for the enumeration of Lb. casei strains in fermented milk. However, the selective potential of this culture medium must be evaluated considering the specific strains of Lb. casei and the starter cultures inoculated in the fermented milk that requires monitoring.
      No preview · Article · May 2014 · Food Microbiology

    + 1 more attachment

  • Osaid H. Alser added an answer in Hepatology:
    Could shaving be considered as a way of HBV/HCV transmission?
    Osaid H. Alser

    Thank you so much for your answers!


  • Suresh Rathi added an answer in Logistics:
    Please i need assistance with regard to interpreting the following logistic regresssion output for a variable. p, OR, CI: 0.000, 0.052, 0.018-0.153.?

    my assessor raised issues with this and i still am not able to resolve it

    Suresh Rathi


    Please let me know the variables and is this analysis for one variable through logistic regression or multiple independent variables with outcome variable (dependent)?

    However, you can write p<0.0001

    OR is become aOR (adjusted odd ratio) (Dont say negative. Say it is in protective nature. Since I am not aware of the two variables so I am unable to provide you proper interpretation.

    CI (confidence interval) =  is also significant


  • Sean Hardy added an answer in Western Blotting Techniques:
    Have I over-transferred my western blot?

    Hi everyone,

    I'm having issues with a western blot I'm running with antibodies for ECM1 and GAPDH in heart and kidney whole tissue protein extracts (mouse).

    I'm using a 'novex' Bolt 4-12% Bis-Tris plus (12 well) Gel for electrophoresis and I currently run my transfer in a glycine/tris-base transfer buffer with 20% methanol @ 10V for 1 hour. 

    ECM1 bands (green - 70kD) are appearing very faint compared to what i have previously seen. I was wondering if i am running my transfer at a too high voltage for too long.

    I've attached a Powerpoint with my first western blot using the ECM1 antibody, and 2 images showing my last attempt at my ECM1 blot using kidney and heart tissue. I should also note that I imaged the blot from both the back and the front (as recommended online if suspecting over-transfer) to test whether i'd mixed up the orientation of the blot in transfer. 

    Any feedback would be greatly appreciated.  

    Sean Hardy

    I Ponceau stained my blot and it was not transferring well enough. 
    Therefore i reduced the methanol concentration from 20% to 10% in my transfer buffer and increased transfer time from 1 hour to 2 hours. 

    The resulting western blot is attached, i am still seeing a non specific band come up at ~30kD. Im not sure why, i think it may have something to do with my GAPDH antibody concentration (red seen at ~40kD).

    Thank you very much for for all your feedback, it has been very useful

  • Hala Hazzaa added an answer in Papers:
    Histology of slough. does anyone know of papers that have looked at different slough forms under the microscope?

    I am looking at what is slough.

    Hala Hazzaa

    Hi dear,  here's two attached articles that might be useful

    Thanks a lot

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Automated and quantitative histological analysis can improve diagnostic efficacy in colon sections. Our objective was to develop a parameter set for automated classification of aspecific colitis, ulcerative colitis, and Crohn's disease using digital slides, tissue cytometric parameters, and virtual microscopy. Routinely processed hematoxylin-and-eosin-stained histological sections from specimens that showed normal mucosa (24 cases), aspecific colitis (11 cases), ulcerative colitis (25 cases), and Crohn's disease (9 cases) diagnosed by conventional optical microscopy were scanned and digitized in high resolution (0.24 mum/pixel). Thirty-eight cytometric parameters based on morphometry were determined on cells, glands, and superficial epithelium. Fourteen tissue cytometric parameters based on ratios of tissue compartments were counted as well. Leave-one-out discriminant analysis was used for classification of the samples groups. Cellular morphometric features showed no significant differences in these benign colon alterations. However, gland related morphological differences (Gland Shape) for normal mucosa, ulcerative colitis, and aspecific colitis were found (P < 0.01). Eight of the 14 tissue cytometric related parameters showed significant differences (P < 0.01). The most discriminatory parameters were the ratio of cell number in glands and in the whole slide, biopsy/gland surface ratio. These differences resulted in 88% overall accuracy in the classification. Crohn's disease could be discriminated only in 56%. Automated virtual microscopy can be used to classify colon mucosa as normal, ulcerative colitis, and aspecific colitis with reasonable accuracy. Further developments of dedicated parameters are necessary to identify Crohn's disease on digital slides.
      Full-text · Article · Mar 2008 · Cytometry Part A

    + 1 more attachment

  • Stanley Kam Sing Wong added an answer in Marketing Management:
    Preferences for Very New Products vs Relatively New Products. How different should the Assessment Techniques be?

    Seeking to understand how very new products differs from known products in terms of measurement. 

    Stanley Kam Sing Wong

    There are different categories of new products:
    A "new to the firm" product can be an existing product that other companies are selling. Example: Burger King's hot dog.
    A "new to the world" product is a true new product. For example, in 1800, Humphry Davy, an English scientist invented the first light bulb.
    A "new to the market" product can be an old product that is selling in other market. For example, corn is a kind of food. The company first grew corn for biofuel and introduced it to the energy market, the corn they sold can be regarded as "new to the market" product from the energy market point of view.
    A improvement, extension, revision of existing product. For example, in 1860, Sir Joseph Swan, an English physicist used carbon paper filament to make better light bulb. The light bulb invented by Charles Brush in 1877 and Thomas Edison in 1879 are all in this category.

  • Biswapriya Biswavas Misra added an answer in Plant Extracts:
    Can I use pure DMSO to dissolve methanolic plant extract for antimicrobial test?

    I wish to perform anti-microbial test with diffusion method in agar using methanolic plant extracts, can I use pure DMSO to dissolve these extract to overcome the solubility problem of these extracts?

    these extracts are obviously methanol soluble but not completely water soluble. can I calculate the toxicity of DMSO by performing control?

  • Abdol Malek Abd Aziz added an answer in Medical Errors:
    Which is the best solution to optimize / reduce medication errors in Computerized prescription system in Leading Multi speciality Hospitals?

    which is the best solution to optimize / reduce medication errors in Computerized prescription system in Leading Multi speciality Hospitals?

    Abdol Malek Abd Aziz

    The Pharmacist must be involved in the design of the computerised system from the beginning, rather than being a user after it is developed. Must carry our trial runs before the final roll-out.

  • Muhammad Abdulrasool added an answer in Matrix:
    How can I fix the NaN error?

    Hi,I want to select a range of elements in matrix p0(i,j), i started from (at-9) to (at+9) and j started from 1 to n, (n=20) and the value of at is known. then do calculation for p0.

    Please I need to fix this error.

    Thanks in Advance.

    Muhammad Abdulrasool

    Thanks for the explanation.