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  • Hamid Reza Hassanzadeh added an answer in Scripting:
    Software to compute least cost path (LCP) in raster files?

    Hello every one.

    I need a stand alone tool so that I can call from my matlab script to compute the LCP distance between two points on the raster. Is such a tool available?


    Hamid Reza Hassanzadeh

    Dear Simon,

    Thanks again, what is a projection problem?

    I attached the raster and points.

    + 1 more attachment

  • Shahid Rasool added an answer in Data Analysis:
    Being a single factor rotation, what is the ideal cut off value of variance explained in EFA?

    Respected Researchers, 

    At an earlier stage of data analysis, I have ten observed variables (Indicators) of construct. After running the EFA, factor rotated into 2 factors with 55.50 % variance explained. By using the concept of single rotation method, few indicators are excluded from the 2nd round of EFA. In this scenario the variance explained fall down till 40.35 %. My question in this context is to what extend researchers can accept the variance explained value for single rotation method?

    with Best Regards, 

    Shahid Rasool 

    Shahid Rasool

    Respected David and Robert, 

    I agreed with prof David about 'simple structure' concept of factor analysis. Actually, try to trace out the simple structure from two to three factors (EFA). On the basis of high factor loading (0.5) indicator are chosen for simple structure to bring in CFA. While performing the CFA with those observed variables (indicators) factor loading further fall down, but fit indices like CFI, CMIN/DF, GFI, AGFI and RMSEA are okay and AVE < 0.5  and C R > 0.7. I need your valuable suggestions at this stage. 

    With best regards, 

  • Prof. Abhay Saxena asked a question in Humanism:
    Mobilization of the crowd is not an easy thing. Can we have some technology driven exercise through which we can awaken collective Consciousness?

    People are working on various programs for the betterment of humanity. Various training program are also been implemented through out the world to make this planet more viable, energetic and harmonious in nature. My question is Can we come out some Technological development may be some instrumentation based chip, programmable components for awakening the collective consciousness. 

  • Patrick Navatte added an answer in Managerial Economics:
    Can anybody suggest best academic literature on management practices and employee performance?
    Can anybody suggest best academic literature on management practices and employee performance?
    Patrick Navatte


    I can suggest you this reference:

    X Chang, K Fu A Low, W Chang : "Non executive employee stock options and corporate innovation", Journal of financial economics 2015, 1165, p 168 - 188.

    best regards

  • Manuel Morales added an answer in Quantum Mechanics:
    In quantum mechanics, we associate operators with physical observables. Why no operator form for the acceleration has been suggested?

    In Dirac theory the momentum and velocity are not related by the simple relation p=mv. Will it be useful to look for an acceleration operator ? In that case shall we define an inertia for the de Broglie  wave? Shall we than define a quantum force that acts on a matter wave resulting in jittery motion as demonstrated by Schrodinger as evident in Dirac theory?

    Manuel Morales

    Will the 2015 Nobel Prize in physics be based (once again) on false-positive data? Is this what we call science?

  • Mohammed El Amine Benamar asked a question in PPM:
    We have difficulties in interpreting certain results related to the change I (V) of the Si nanowire decorated with Ag, Pd, Pt, Au,?

    We developed nanofols structures Al / NFSi / p-Si / Al with undecorated silicon nanowires and decorated for producing a hydrogen gas sensor.
    The characteristic I (V) of the reference structure Al / NFSi / p-Si / Al does not exhibit significant variation with respect to various concentrations of H2 gas.
     It was also observed that the characteristics I (V) Pd and Au decorated structures are similar to those of the ohmic structures unlike decoration Ag and Pt which have schotky structures.
    However, we found that the reference sample, ie undecorated structure and decorated structures respectively by Ag and Pt have a rectifier nature, changes in the reverse current is relatively low compared to any variations to the current Direct.
      The biggest change compared to the pressure of H2 gas is observed for decoration with the Pt. However, this change is not significant for the reverse current, which decreases as the concentration of H2 increases.
    The response time required for I (t) of the sensor to reach 67% of the variation in current from the opening of the throttle, and the  recovery time to reach 67% of the variation in current from the closing the gas.
    The lowest response time 46.01s and 56.11 s and 76.28 s recovery time of 56.38 s and were observed for the decorated structure for H2 at respective concentrations of 15 ppm and 85 ppm.
     The lowest response time of 54.3 s and 40.79 s recovery time was obtained for the structure Ag decorated to the highest concentration of H 2 (174 ppm), however, the time and answers highest recovery were recorded for the decorated structure Pt and this for all the H2 concentrations.
      The response and recovery time relatively short decorated Au and Ag structures can be attributed respectively to the high rate of adsorption and desorption of H2 gas.

  • Satish Modh added an answer in Vedic:
    How can satoguna be increased in individuals for improving psychological health?

    Charaka Samhita which is the oldest texts of Ayurveda explain triguna concept of human psychology that consists of Stoguna, Rajoguna and Tamoguna. Even though we have psychometrically tested scales to measure these gunas, are there any interventions in the vedic or post vedic texts in order to improve the guna balance for positive psychological health? Are there any modern studies on this subject?

    Satish Modh

    I have been able to use the above mentioned framework for determining psychological health. I will submit my working paper on my page on research gate in two weeks time.

  • Sikha Deka added an answer in Soil Fertility:
    How can we proceed for decision on soil resource-based cropping sequence?

    Development of soil resource inventory of a given area , is considered highly imperative to take decisions on the options about the suitability of different crops in a farming system mode. At the same time, the information on edaphological requirements of different crops , is equally paramount , so that both are super-imposed in such a way, to delineate soil-crop analogues. This will pave the way for better land utilization efficiency. My further querries in this regard are as follows:

    * How should we develop a soil resource inventory ?. Shall we go for master soil pfofile stdies  or follow the grid- based soil sampling  coupled soil profiles to be later used for developing soil fertility variograms?. 

    * How shall we identify the soil fertility constraints of multiple nature from such soil resource inventory?.

    * What methodology , shall we adopt to identify   optimum soil requirement for different crops ?.

    * How should we identify the cropping sequence based on such soil resource inventory?.

    * Whether cropping sequence and land utilization efficiency are inter-related ?.If so , in what way?.

    I request my esteemed colleagues to share their experiences on these issues. Regards

    Sikha Deka

    We are perhaps drifting from main course of the topic. Please cite such success stories where soil resource inventory has been effectively used in harvesting potential productivity. The answer such as this takes away the incentives of soil as a natural resource.

  • Titu Thomas added an answer in Thermal Evaporation:
    Can we make flexible solar cells on metallic foils by chemical spray pyrolisis technique?

    I have been trying to fabricate flexible solar cells on metallic foils like copper sheets. using the method of chemical spray pyrolisis. but haven't quite worked out yet. the copper sheet is placed on a heater and the required solution is sprayed to get a thin film over it.and finally an electrode is thermally evaporated on to the so formed thin film. the copper foil itself is used as the back contact. on taking the IV measurements the device shows diode like behavior  but no current or voltage on illumination.  why is it so ?? how can we identify if that junction formed is a p-n junction or a schottky junction?  kindly suggest..

    Titu Thomas

    I'm really sorry for not being informative about the materials.But before i proceed in anyways whatsoever, I want to do a major literature review on the topic . can anyone suggest me some information or any publications regarding works on solar cells on flexible metallic foils. I'm not able to find any. please help.

  • Kleomenis Kalogeropoulos added an answer in Rainfall Runoff Modelling:
    How do I read the runoff duration curve?

    I read some journal about water discharge, many research show picture about runoff duration curve. but I still can not understand how to read? or meaning from that curve?. please give comment or suggestion. I am student (master) and preparing paper for publish. your comment is helpful for me

    Kleomenis Kalogeropoulos

    You can check also these:



  • Behrouz Ahmadi-Nedushan added an answer in Social Cognition:
    Should we hold people accountable for their mistakes?

    Dear RG friends,

    This is an important matter, for me as researcher and as human being. It is about errors and we know: "Errare humanum est, perseverare-diabolicum".

    Human errors and the adverse events which may follow, are problems of psychology, systems thinking, behavioral sciences and engineering (in technical systems). Understanding, predicting, and modulating human performance in any complex setting requires a detailed understanding of both the setting and the factors that influence performance. The social cognition research on cycles of accountability clearly captures the complexity of the effects and demonstrates the naïveté of the belief that improving society only requires holding others accountable.

    The “culture of blame” never worked. Why don't people just follow the rules, legislation, procedures?

    My starting point in formulating this question was occupational and system safety, but I would like to have your (expert or personal non expert opinions) in a general sense of human accountability in various fields, activities and situations?

    + 1 more attachment

  • Gert Van der Zwan added an answer in Theoretical Physics:
    I am stuck with a complex integration given in the file attached herewith. Can any please suggest me the way to solve such integration?

    I am stuck with a complex integration given in the file attached herewith. Can any please suggest me the way to solve such integration?

    Gert Van der Zwan


    I'm afraid I have to agree with Mutze and Leyvraz, sorry. Although it is likely to be as unsuccessful as your search for a zeta free solution of the integral, I'd rather spend my time finding a proof of Riemann's conjecture. 

    Regarding your final question about how Riemann found his integral representation: I have no idea. The brain of a mathematician of the stature of Riemann is a deep mystery that we are unlikely to ever comprehend. I can only marvel at it. And of course they only write down their final thoughts, not all the wrong paths they have taken before hitting on something beautiful.

  • K. Kassner added an answer in Riemannian Geometry:
    If any coordinates will do in General Relativity, is spatial curvature necessary? Is GR more complex than necessary, and is curvature verified?

    GR was introduced along with the principle that not only is no coordinate system preferred, but that any arbitrary coordinate system would do.  The complex mathematical machinery of covariance was introduced (including tensors) to express the laws of physics, any of the laws not just GR, in arbitrary coordinates.  This allows coordinate systems in which the distances vary with position and orientation, and in which the speed of light is non-isotropic (varies by direction), and such coordinates are routinely used in famous solutions such as Schwarzschild.

    So, it is not just the curvature of Riemannian geometry that requires complexity, but most of it is required by independence from coordinates.  And if indeed physics is independent of coordinates, can coordinates be found for solving GR problems in which space (if not spacetime) is flat and therefore graspable to the ordinary intuition?

    For an introduction to analysis of orbits using only time dilation, not  spatial curvature, see paper linked below.  GR was derived from the equivalence principle on the assumption that curvature was the only way to explain equivalence, but this is an argument not a proof according to GR verification authority Cliff Will.  If another method is available, it becomes a weak argument.  Is there empirical proof of curvature?

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Frequency and therefore time dilation is a function of potential in a gravitational field, as in for example "gravitational redshift." We consider using time dilation as a proxy for potential in a Hamiltonian. Thought experiments illustrate that redshift, or time dilation differences, account for the total energy potential difference between locations in a gravitating system. Unlike the weak field limit or so-called linearized-GR, we use a time dilation formulation of all motion. Therefore one might expect that a Hamiltonian so formulated gives the full and correct equations of motion within such a system, and we find that it does, but only up to coordinate singularities and not including rotational effects unrelated to potential such as Lense-Thirring.
    K. Kassner


    "So as long as they keep moving, Mom and Dad will think Jane is older."

    This is wrong according to Boughn's analysis, and I think he is right. As long as they are moving at the same speed, they age the same way according to Mom and Dad. At each moment, they have the same time dilation factor (which depends only on the momentary velocity) and integrating up their proper times gives the same time at each moment in the frame of Mom and Dad.

    "As Dick and Jane slow down, no matter how slow or fast, the clock skew in the other frame (Mom and Dad), which remains inertial, will reduce until finally when Dick and Jane are stopped, there is no clock skew and Mom and Dad realize Dick and Jane are the same age.  But for Dick and Jane themselves, they were always the same age."

    No. As you can see explicitly from Eric's diagram, the leading person of the two is always older. Both during the acceleration phase (which Eric does not say explicitly), but also after it. Just watch the diagram. You are misusing your own paradigm of "leading clocks lag", which can in fact be used to clarify the situaion. But one has to use it correctly :-). "Leading clocks lag" is true when the clocks are synchronized in their own frame of reference (they are assumed to share one, and to move inertially, but that may be replaced in many cases by "momentarily at the same velocity"). Here we have a situation, where the clocks are synchronous in a fixed inertial frame, in which they move. Hence, the leading clock must lead in their proper frames.

    If they come together, after acceleration has stopped, by slow motion in a symmetric fashion (i.e., each covering half of their distance slowly)  then an age difference will prevail and the leading twin will be the older one.

    My reason for addressing you directly in the first post where I confirmed that Boughn's analysis is sound, was probably that in the preceding post you stated something like "sorry to disappoint, but this is my area of expertise" which is obviously a pretty boastful statement. (It is also erroneous, as your expertise in this domain is very limited.)

  • Manuel Morales added an answer in Gravitation:
    In GR, can we always choose the local speed of light to be everywhere smaller that the coordinate speed of light? Can this be used in a theory?

    It seems that many, if not all, solutions of Einstein's equations, such as black holes and grav. waves, can be given coordinates x\mu in such a way that the local speed of light is always slower than the coordinate speed of light. Think of gravitational lensing: the index of refraction of a gravitational potential always seems to be >1, in practical examples, so a gravitational potential slows light down, and never speeds it up (if coordinates are chosen carefully). This wouldn't be true for a negative-mass Schwarzschild solution, but that seems to be outlawed in nature.

     Now this was only a conjecture, I have not attempted to prove it. How would a rigorous mathematical theorem be formulated? And did anybody - and here I mean a wise person, not the average blogger - ever try to do something interesting with this observation? Like constructing a “hidden medium” for curved space-time?

    Manuel Morales

    Will the 2015 Nobel Prize in physics be based (once again) on false-positive data? Is this what we call science?

  • Silburn Clarke asked a question in Bitcoin:
    Will bitcoins and blockchains supplant financial markets as we know it?

    The development and rise of the bitcoin / blockchain phenomenon has huge implications, positive and negative, on the future of money and global payment systems. Will it be paradigm shifting ?  By decoupling from conventional global benchmark currencies, will it level the playing field for emerging economies

  • Jazelle Malicia Jones asked a question in Instructional Technology:
    Can anyone assist me or direct me to any undiscovered innovators in the field of Instructional Design, Instructional Technology or Distance Education?

    the individual must have contributed to the fields of Instructional Design, Instructional Technology or Distance Education.

  • Prof. Abhay Saxena added an answer in Internet of Things:
    Research of Embedded Internet Technology for Internet of Things

    Development of Internet of things, the application of embedded Internet technology will be wide.

    Prof. Abhay Saxena

    Dear Sureshji:

    nice to find you interest and IOT research. Do get in with your guide as in a Ph.D. we cant cover enormous things. some of the areas are listed below for your kind help.

    Cyber-physical and other IoT systems architectures
    Network architecture and system design in IoT
    Addressing and naming in IoT
    Programming models for the IoT
    IoT and Cloud computing
    Integration with existing standards and protocols (e.g., RPL, 6LoWPAN, CoAP, MQTT)
    Data management in IoT
    Machine-to-machine (M2M) communications in IoT
    Energy efficient management and sustainable operation of IoT/M2M objects
    Information centric network for IoT
    Social networks for IoT
    Context-awareness for IoT
    IoT traffic characterization
    Privacy, Security and Trust for IoT
    Modeling and simulation of large-scale IoT scenarios
    Testbed, prototype, and practical systems for IoT use cases

    with good wishes for your future work.

    Prof. Abhay

  • Sayed Mohammad Tariq Zafar added an answer in Export:
    Is the United State dependency on China is strategic and pathetic?
    Sayed Mohammad Tariq Zafar

    According to Trevir Nath

    While the United States and China haven't always seen eye to eye on diplomatic issues, particularly human rights and cyber security, the two counties have built a strong economic relationship, with significant trade, foreign direct investment and debt financing. Two-way trade between China and the United States has grown from $33 billion in 1992 to $590 billion in 2014. After Mexico and Canada, China is the third-largest export market for U.S. goods, accounting for $123 billion in U.S. exports. As for imports, the U.S. imported $466 billion in Chinese goods in 2014, primarily consisting of machinery, furniture, toys and footwear. As a result, the United States is China’s largest export market.

    Alongside an extensive amount of foreign trade, China has been a popular destination for U.S. foreign direct investments. The stock of foreign investment from the U.S. into China exceeded $60 billion in 2013, primarily in the manufacturing sector.

    That being said, the U.S. has a significant trade deficit with China due to U.S. Treasury bonds. Currently, China is one of the largest holders of U.S. debt, amounting to $1.2 trillion. For China, Treasuries are a safe and stable way to maintain an export-led economy and creditworthiness in the global economy. As long as China continues to hold a massive amount of forex reserves and U.S. debt, some market observers believe the U.S. economy could be essentially at the mercy of China.

    Is the United State dependency on China is strategic and pathetic? - ResearchGate. Available from: https://www.researchgate.net/post/Is_the_United_State_dependency_on_China_is_strategic_and_pathetic [accessed Oct 4, 2015].

  • Mohamed El Naschie added an answer in Discovery:
    Will the 2015 Nobel Prize in physics be based on false-positive data?

    On April 30, 2011, at an American Physical Society meeting, I presented my initial findings that showed that Albert Einstein's notion of hidden variables, although not local, was indeed correct.

    In 2012, I applied my discovery of these hidden variables to the Higgs boson initial discovery and found it to be based on omitted-variable bias since the two origin variables that caused the predicted effects observed were not factored into the results (see "Assumed Higgs" link). Since the two origin variables are mutually exclusive yet can produce the same results, obtaining false-positive data from experiments based on omitted-variable bias is unavoidable (see "Tempt Destiny Experiment Results" link). In science, a discovery cannot be obtained based on false-positive data. Yet in 2013, physicists confirmed that they discovered the Higgs boson and then was awarded the same year the Noble Prize for their discovery. This all took place despite both parties being informed in 2012 of the discovery of Einstein's hidden variables which would negate the Higgs boson discovery since the Large Hadron Collider cannot detect which origin variable caused which particle collision effect which in turned caused the decay product effect used as evidence for their discovery.

    In the meantime, I have invited the general public to confirm if the Higgs boson discovery was or was not based on an omission error (see "How Grade School Children Can Confirm If Quantum Mechanics Is a Fundamental Theory - Class Assignment Search For First Cause" link).

    It is rumored that science self-corrects itself when a new discovery supersedes previous knowledge. If this is true then how long does it take for such a correction to take place and will the 2015 Nobel Prize in physics be given for yet another discovery based on false-positive data?

    + 2 more attachments

    Mohamed El Naschie

    mean time dearest Marinda let do like zorpa the greek 

    Dr. Mohamed El Naschie
    Published by Mohamed Naschice · 4 mins · Edited ·
    Dr. Mohamed El Naschie
    Published by Mohamed Naschice · 5 hrs · Edited ·
    «السيد وزويل ويعقوب والنشائي» في المقدمة
    مفاجأة.. مؤشر «SCOPUS» الدولي يُصنف عشرة علماء مصريين وسط أهم 909 علماء على مستوى العالم
    23 يوليو 2015 08:43 مساءٍ المرصد المصري 712
    في مفاجأة من العيار الثقيل كشف مؤشر "SCOPUS" الدولي، الذي يُصنف علماء العالم، طبقاً لضوابط وشروط، عن دخول عشرة علماء مصريين وسط أهم 909 علماء على مستوى العالم، طبقا لثلاثة مستويات وتصنيفات عالمية وهي "H-index" و"i10- index" و"Scupes" وهي أجندات دولية لتصنيف العلماء والباحثين والمتخصصين في مجال العلوم والبحث العلمي طبقاً لما يقدمونه في مجال العلم.
    القائمة تربع عليها العالم المصري مصطفى السيد، المرتبة الأولى على العلماء المصريين والعرب، بـ79 نقطة، يليه الدكتور مجدي يعقوب برصيد 63 نقطة، ثم أحمد زويل برصيد 60 نقطة، ثم الدكتور محمد النشائي برصيد 43 نقطة، فالدكتور فاروق الباز برصيد 16 نقطة، وخلفه جاء الدكتور عصام حجي، المستشار العلمي لرئيس الجمهورية برصيد 12 نقطة، ثم الدكتور فينيس كامل جودة بالمركز القومي للبحوث برصيد 4 نقاط، وفي الم


    anthony quinn: zorba the greek
    Ante el desastre total, aprestate a bailar...genial inyeccion de optimismo de Antony Quinn, Mikis Teodorakis, Nikos Kazantzaquis y otros. Tiene hasta comicid...

  • Josef Punčochář added an answer in Oscillators:
    How can we classify or group oscillators ?

    So far I have found that the number of amplifiers may be used as follows:

    Oscillators type A:

    1 amplifier and a feedback circuit.  

    This is the Barkhausen topology

    Oscillators type B:

    2 or more amplifiers and a connection circuit.  

    This is the Non Barkhausen topology

    Oscillators type C:

    No amplifiers !

    These oscillators are based on a dynamic negative resistance e.g. a tunnel diode

    In short

    Oscillators are nonlinear electronic circuits

    which are searching for a bias-point

    Josef Punčochář

    Hello Erik - není zač (not at all).

    If we are able to build admittance linearized model of the investigated circuit, we just examine determinant, always.

  • Alfredo Pereira Junior 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.

    Alfredo Pereira Junior

    Dear Arnold, one more round of disagreements:

    Arnold: Third-person perspectives are sub-sets of first-person perspectives so they are experienced (as must all conscious experience) from the first-person perspective. This was resolved many posts ago, either in this thread or the thread on mathematics.

    Alfredo: What I stated is the reverse: that not all first-person experience descriptions are third-person descriptions. They are different, but not disjunct (see below).

    Alfredo before: "Therefore, the descriptive domains - although being distinct - are not disjunct. Difference is not a synonym of disjunction."

    Arnold: Depends on which dictionary you use. In my dictionary, a disjunction is a sharp cleavage or separation. So 1pp and 3pp descriptions are disjunctive because they occupy separate/distinct descriptive domains.

    Alfredo: For "disjunction" I am using the basics of Set Theory - exactly as you wrote above. However, for "difference" or "distinction" I do not use the same set theoretical meaning of  "disjunction". Two distinct or different things may have an intersection (common elements). Therefore, the first and third person descriptions, although being different or distinct, are not disjunct as you claim.

    Alfredo before: "The thesis that objects are placed where we perceive them to be is not a thesis about the infallibility of perception, but a thesis about the location of perceived objects being external to the brain."

    Arnold: This is just another way of saying that our perceptions are transparent brain representations of the world around us. This is an essential part of my working definition of consciousness.

    Alfredo: If you really assume the transparency idea, then the phenomenal world cannot be literally in the brain. A transparent medium shows at one side what is there at the other side. There is an informational field connecting both sides; otherwise, the medium is opaque. You cannot have transparency and brain internalism at the same time!

    Arnold: What is missing from your formulation is the proviso that our perceptions are from the perspective of a fixed point of spatio-temporal origin -- the core self (I!).

    Alfredo: I would not state that it is a fixed point, as we discussed before. This thesis soulds like the Big Bang hypothesis.... Complex functions or processes cannot be attributed to a single point. However, in Velmans' approach (that I subscribe) there is a first-person perspective that - in the case of perception - he describes as an effect of projection for which we do not know the mechanism. I have asked everybody here to propose a mechanism, but nobody has tried! How do signals inside the brain are perceived as objects external ot the brain? My guess is that it is an information field based on a quantum-like entanglement of co-variations outside and inside the brain. In the case of vision, the external variation is produced by the interaction of while light with the surface of an object. In the brain, the variation is a change relative to the baseline in the retinoid system. The laws of quantum physics somehow create a connection between both events, such that the brain event becomes an "intentional" state that refers to the external event.

  • Domenico Voltolina added an answer in Growth Medium:
    Can i autoclave f/2-silica medium (the final one)? will the pH change or any other breakdown/precipitation of the nutrient?

    I'm planning to make f/2-silica medium for culturing my nannochloropsis. because of the time limit, i cannot use membrane filter sterilization, so that i come up to autoclave it. I want to know if there is any change in my media about the vitamin, the mineral and pH of the f/2-silica medium.

    Domenico Voltolina

    oops, sorry, I missed your answer. Since there are no silicates (which will not precipitate, although they might polymerize and give a slightly opalescent appearance to the medium) the only reason for seeing a precipitate after autoclaving would be the presence of phosphates, which might coprecipitate with metals.

    just make sure that they will redissolve if you leave the medium standing a few hours. If they don't, check  PO4 concentrations. Filtering off the precipitate and having it analyzed would also be a good idea. Loss is probably unimportant since you apparently have normal growth, but knowing as much as you can about the medium is the only good way  to go.


  • Francesco Elia Marino added an answer in Urology:
    Testicular cancer: risk age 18-39. Any explanation?
    I recently gave a talk on testicular cancer, and I received a very interesting question about the risk age. We don't actually know why testicular cancer affects, mostly young men. In the literature, there is not a main hypothesis about that. I am asking this question to an experienced researcher in this field. Do you have any possible explanation or hypothesis?
    Francesco Elia Marino

    I am not aware of any study correlating Marijuana with an increase incidence of developing testicular cancer.

  • Mera Saad added an answer in Troubleshooting:
    Hello, please I need help in these Troubleshooting?

    2. A researcher prepares an agarose gel, sets it up in the electrophoresis chamber, loads samples and turns on the power supply to the correct voltage.  Thirty minutes later, it appears that the gel has melted and the buffer is very hot (steaming).  What could be the problem?

    3. A researcher prepares plasmid DNA using the minispin kit.  Nanodrop analysis of the DNA shows that the DNA is of good quality and high concentration.   A sample of the DNA is run on an agarose gel.  No bands are visible.  The DNA ladder and positive DNA control (both of commercial origin) are also not visible on the gel when viewed on the transluminator.  What is the most likely explanation for this problem?

    Mera Saad

    Hi Paul, 

    Could you please show me by calculating how did you get Q.1? 

    Thank you 

  • Khandoker Mahmudur Rahman added an answer in Online Surveys:
    Which is the best free online survey web page?

    I would like to do a survey and I wish to know which is the best free online survey web page in order to do a qualitative research.

    Khandoker Mahmudur Rahman

    Most welcome!

  • Ahmad Rayan asked a question in Personality Disorders:
    Does personality disorder require hospitalization?

    if yes, which types of personality disorder require hospitalization?

  • Ht Liang asked a question in Ligation:
    Is it difficult to ligate a small DNA part (about 30bp long) to a vector? What possible steps could be taken to increase the ligation efficiency?

    Carried out ligation a couple of times in different ratios and incubation times. Transformation results: negative has more colonies than positive.

    Really appreciate the help, thanks.

  • Sayed Mohammad Tariq Zafar added an answer in Inflation:
    How to differentiate political inflation with socio-economic inflation?

    It is impossible to explain and judicially predict inflation in true seance. No economist in the world can predict the jerks of inflation and even its true causes. It is perpetual in existence as it is other side of economic growth coin.

    Sayed Mohammad Tariq Zafar

    In order to hedge the economy from inflation impact it is important to aim for nutritional security rather than exploring the potentials at demographic level depending upon sizable young population. It is also important to control prices of food products at significant level. This will become possible by addressing and effectively correcting the supply- demand imbalance in the agriculture sector and by efficiently modernizing the supply chain system. To support the economy and to keep manufacturing cost at low level concrete efforts are very much needed to secure energy security for the country.