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  • Wolfgang F. Schwarz added an answer in Analogy:
    Is analogy the key to understand thinking?

    Hofstadter and Sander write in their book "Surfaces and Essences: Analogy as the Fuel and Fire of Thinking" that analogy is a key issue for cognition and perception. They put analogy into the center of all mental tools. I think analogy is a powerful tool but it is a tool beside others.

  • Sahar Parsa added an answer in Animal Protection:
    Mineral intake in cattle
    What do you recommend, a PO mineral (salt) intake or IM mineral to cattle? I observed that in a herd of cattle not all the animals have the same access to salt and there are a lot of losses due to weather and other factors. Are we losing money offering salt to cattle?
    Sahar Parsa


    what is the role of microorganism in the rumen (or stomach or cecum)of chelating minerals?

  • Pelumi Oguntunde added an answer in Probability:
    What is the distribution of Log (Inverse Gamma) random variable?

    Dear colegues,
    Good day

    Suppose I have a random variable X∼Inverse Gamma(k,θ)  , and I define:


    I would like to find the probability density function of Y

    Best wishes

    Pelumi Oguntunde

    Thank you for the information @ Bryan

  • Charles Francis 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?

    Charles Francis

    Mozafar, yes, this would be the consequence of the photon having a mass small enough that we have not, as yet, been able to measure it. It would not alter the form of the laws of physics by a measureable amount.

  • Sushilkumar A. Jadhav added an answer in Nano:
    How can I disperse TiO2, SiO2, ZnO and zeolite nano particles in hexane organic solvent?

    I am working with insect pheromone and I want to disperse the mesoporous TiO2, SiO2, ZnO and zeolite nano particles in hexane organic solvent for slow release of pheromone. Anybody having experience, please help me.

    Sushilkumar A. Jadhav


    Remember if your formulation will be the pheromone dissolved in hexane and you add the porous particles to this solution. Some of the pheromone will enter the pores and this is called as loading of the particles and some quantity of the pheromone will remain in the solution. So you have to separate your particles from the solution may be by centrifugation and then determine the actual loading. Because if you want a slow or controlled release you should be interested in the pheromone loaded inside the pores on the particles. Then you can make a fresh suspension of the pheromone loaded particles in desired solvent (not necessary hexane now) in which the pheromone is soluble and determine the quantitative release with time. I hope this will help.

    Good luck.

  • Anand Dev Gupta asked a question in Water Pollution:
    How to mitigate the induced (specific to artificial recharge) ground water pollution in India?

    The recent ​trend or ​fashion to make ​recharge pits ​everywhere, ​particularly in ​cities>>> I ​think, there is ​a potential ​hazardous water ​may directly ​contaminate the ​aquifers. We ​may left ​without clean ​water on both ​surface and ​subsurface. Our ​recharge ​filters are not ​fit enough to ​clean mixture ​of waters in ​cities.  ​During my ​school days, we ​used  ​drink water ​directly from ​hand pump or ​tap, and from ​the fields but ​now trend is ​changing even ​in our small ​village --""​pure water is ​scarce". In ​future, we need ​water filter ​for every glass ​we drink. ​

    "" I think ​solution could ​be give more ​importance to ​treat and ​protect the ​natural water ​depressions (​water bodies), ​naturally both ​our surface ​water bodies ​and aquifers ​safe.""  ​That is how it ​designed (​geomorphology ​and geology) by ​nature. ​

  • Mohamed Sobhy Ibrahim added an answer in Student Engagement:
    In brief, how do you sustain the students' engagement, enjoyment, happiness and enthusiasm in the design studio?

    Teaching Design is not about the final product itself, the process is the key for the experience. the struggle might be physical, mental and sometimes emotional. Sleep deprivation, depression, unconsciousness reflections ...and more.

    To sustain the students' envolvement and productivity during all that, the experience must be worth it!

    How do you achieve this in your studio? Starting from planning the tasks to the management of the studio itself?

    Mohamed Sobhy Ibrahim

    for a reason, I can't reach it! so i do not know what you exactly mean? 

  • Jawaid Ahmed asked a question in Ethanol:
    If any one can tell me the protocol for catalse estimation using KMnO4. Unable to understand the quantities give in papers available?

    concentration of ethanol and triton to be added

  • Cláudia Santos Martiniano added an answer in Qualitative Data Analysis:
    Which are different qualitative data analysis techniques ?

    My research is focusing on Qualitative and Quantitative Data collection. I would like to know more about different Qualitative Data Analysis Techniques. How do we go-ahead about Qualitative Data Analysis?

    Cláudia Santos Martiniano

    Uma das principais técnicas de análise de dados qualitativos é a Análise de Conteúdo. A pricncipal expoente sobre o tema é Laurence Bardin.

  • Muhammad Tayyib Naseem added an answer in FASTA:
    Can someone help with extracting multiple sequences using their ids (.txt) from a bigger file (.fasta) altogether?

    Suppose I have two files- one big fasta file with loads of sequences and one small text file with ids of few selected sequences. 

    1. How can I extract the sequences with ids in the text file, altogether from the larger file? (Not one by one, but at the same time)

    2. How can I cut and paste or delete the sequences with ids in the text file from the larger fasta file? (not one at a time, but altogether)

    Any script or command will be highly helpful. Thanks in advance.

    Muhammad Tayyib Naseem

    Make a list of sequence ID in .txt file 
    each ID in new line
    then upload here http://www.ncbi.nlm.nih.gov/sites/batchentrez

    you will get all together in one page 

    select and Download all.

    If you want to rename them follow myself explored protocol as in attachment file.

  • Ahmad Khairuddin bin Muhammad Afiq added an answer in Mixers:
    How I can calculate mixing index in micro mixers-experimentally and numerically through simulation-?

    how I can calculate mixing index in micro mixers(experimentally and numerically through simulation)?

    Ahmad Khairuddin bin Muhammad Afiq

    You can try use COMSOL Multiphysics software to simulate both experimental data (by interpolating the data & even extrapolate it) and numerically (with finite element method and specific timestep and geometries).

  • Jibran Khan added an answer in Geoinformatics (GIS):
    Any advice in assigning weightage to the spatial layers for GIS based multi-criteria decision analysis?

    Considering the scenario of GIS usage for multi-criteria decision analysis to evaluate the land suitability, do you think is it appropriate to assign weightage to the spatial layers based on the published literature?

    Jibran Khan

    Thank you guys for the awesome feedback.

  • Mykola Kozlenko added an answer in Computer:
    How to compute Lambert Function (W)?

    Lambert function has been proposed by Jean-Henri Lambert, some times called Omegat function (W).

    the equation can be written as following:

     xexp(x) = z  this means that x= W0(z)

    So the question is , how can i compute W0?

    Mykola Kozlenko

    You can use lambertw(a) function in MATLAB

  • Ali Taghavi added an answer in Geometry and Topology:
    Can one provide an example of a principal fiber bundle with this property?

    1)Is there an example of  a  non trivial principal bundle $P(M,G)$ such that the total  space  admit a foliation which all leaves are diffeomorphic to $M$? 

    2) Is there an example of a non trivial principal bundle $P(M,G)$ with the property that every integrable distribution on $M$ can be  lifted to an integrable distribution on the total space?

    Ali Taghavi

    I received some answers to  the first question in MO as follows


  • Subhash C. Juneja asked a question in Syria:
    Looking into turkish downing of russian jet, can we call NATO as mafia of western nations?

    Definition of mafia is that if a gang person gets in trouble, whole gang is ready to help him. Syria downed the russian jet. All NATO members are ready to help so that russia has no choice but to shut up his mouth. In this regard, Can NATO be called Mafia?

  • Cláudia Santos Martiniano asked a question in Medicalization:
    Can anyone send me the Medication Appropriateness Index (MAI)?

    Medication Appropriateness Index

  • Ahmad Khairuddin bin Muhammad Afiq added an answer in Modeling:
    Does anyone know any good reference that comparisons between data-driven and non-data modeling?

    Does anyone know any good reference that comparisons between data-driven and non-data modeling?

    Ahmad Khairuddin bin Muhammad Afiq

    Its very difficult to find both data driven and non data modelling at once...but if you are in diffusion equation modelling my personal reccommendation is papers and journal from Song Wang and Xia Lou regarding optimization to estimate effective drug diffusivity.

  • Jorge Morales Pedraza added an answer in Renewable Energy:
    Is any low price and high efficiency solar panel available?

    Is any low price and high efficiency solar panel available ? Solar panel is one of the renewable energy source material. But price little high now, any low price solar panel or other material available? is any research related to it? 

    Jorge Morales Pedraza

    The cost of solar panels have been decreased in the last decades ad it is expected that this trend will continue in the coming years. The efficiency of the current solar panels are somehow low, between 15-25 %, but some research activities could increase this level in the coming decades.

    International reference: Solar (US$0.15-US$0.30/kWh). The high cost of these types of renewable energy source is largely due to the high price of silicon crystals. Silicon prices continue to rise as their widespread production applications are leading to supply shortages. However, newly developed alternative materials could bring the cost down below US$0.05/kWh in the near future.

    It is extremely important to note the decline in solar PV costs in the coming years. For example, the average price of approximately Wp of solar PV modules, traditionally the most expensive SFV element is:

     Table: Price per Wp of PV modules

    2008                           US$4/Wp

    2011                            US$2/Wp

    2014                           US$0.61/Wp (agosto 2014)

    2020                            US$0.35/Wp (expected) 

    Cost of major powers investors: Today US$0.15/Wp; in 2020: less than US$0.10/Wp

    Cost of metallic structures: Today US$0.25/Wp; in 2020: less than US$0.12/Wp

    Wiring cost: The wiring cost is expected to decreases in 2020 due to an increase in the solar PV module efficiency, which has to be 20%.

    Current costs and perspectives of PV modules components Si-c: Its costs have declined. Today the range is between US$0.50 and US$0.94 cents/Wp; the average is US$0.61 (September 2014) cents/Wp. Keep in mind that about 60% of world production is multi crystalline silicon modules (poly) and 30% mono crystalline silicon. The costs of multi crystalline modules are lower (average of about US$0.57 cents/Wp). Higher efficiency monocrystalline are more expensive. It is predicted that in the next five years the today average of US$0.61 cents/ Wp, will be less than US$0.40 cents/Wp. 

    Investors: The higher power investors are cheaper, between US$0.13 and US$0.15 cents/Wp. Those of lesser powers to smaller systems can reach about US$0.40 cents/ Wp. The medium-term forecast is that costs will continue to decline below the US$0.10 cents / Wp for higher powers.

    Structures: The cost of steel structures for systems that support perpendicular winds of 150 km / hour, will decrease as a result of better designs. Its costs have been above US$0.25 cents/ Wp, but there are designs that can take the cost below US$0.12 cents / Wp. With the increase in the efficiency of the modules will decrease the cost of the structures.

    Electricity: Includes wiring and other electrical parts of the solar PV system. With the increase in the efficiency of the solar PV modules will decrease the cost of cabling.

    Labor: This expenditure is related to salaries and payments by human labor, which is very favorable in the case of Cuba, because the salary is calculated in US$, but payed in Cuban pesos. For example, installers of solar PV systems in developed countries earn US$25 to US$30 per hour, and of course, this cost is much smaller in Cuba.

    Operation and maintenance (OM): Solar PV has one of the lowest costs in O&M of all energy sources used for electricity generation, and a large part of it is on salary cost.

    Depreciation/Deviation: The most important is the decrease of the initial efficiency of the solar PV module during 25 years of operation, which is 20%, that is, the solar PV panels should be replaced although it is still has an efficiency of 80%. This depreciation takes into account the need to generate an average of 1,360 kWh/ kWp per year (27,200 in 20 years and 34, 000 in 25 years).

    Recycling: A new element for solar PV systems that has not being taken into account until now is the decrease in the cost of solar PV systems as a result of the recycling of the solar panels once they met their useful life (25 years). This element should be considered in the future due to the possible reuse of glass, silicon, aluminum and tin. There is no need, in most cases, to a new earth movement, and it is also possible to reuse metal structures supports, at least in the form of steel scrap and aluminum. For this reason, solar PV systems are highly recoverable.

    Lifetime of the SPV: On solar PV calculations costs, the number of years of useful life of the module, 25 years, was used as reference. Due to improvement of encapsulation and decreased degradation, that number of years continue to increase. It is expected that within a few years (2020), lifetime of solar PV modules possibly lasting about 30 years, which in turn will further reduce the cost per kWh as compared to the total cost divided by the number of hours; for example, to 1,360 kWh / kWp within 25 years of lifetime correspond to 34,000 peak hour generation, and with 30 years of lifetime the total hours of generation will increase to 48,800 hours.

    Efficiency of solar PV modules: Another element that will influence the decrease of the costs of solar PV systems is the increase in the efficiency of solar PV cells and modules; for example, with an increase in the efficiency from 15% to 20%, it will require an appreciable reduction of the area occupied by a similar magnitude of solar PV power.

  • Rashad elsaied Elzeny asked a question in Drainage:
    Research on drainage baisn of sinai?

    research on drainage baisn of sinai ?

  • Sidharta Chatterjee asked a question in Hyperparathyroidism:
    What is the risk of developing hyperparathyroidism in patients with diabetes mellitus?

    Are some diabetic patients genetically predisposed to hyperparathyroidism? There is a link between thyroid disorders and DM. What about the risk of developing hyperparathyroidism in patients with DM?

  • Glenn Borchardt added an answer in Theoretical Physics:
    Does the uncertainty principle violate the conservation of energy law?

    Aephraim Steinberg of the University of Toronto in Canada and his team of researchers have performed measurements of photons and showed that the act of measuring can introduce less uncertainty that is required by Heisenberg’s principle. Violation of Heisenberg’s Measurement-Disturbance Relationship by Weak Measurements


    Is reduced the amount of uncertainty by the development of precision our tools? Does Heisenberg's Energy-Time uncertainty inequality imply non-conservation of energy?

    Is the uncertainty principle a property of nature or a result of observer tools?

    Does the uncertainty principle prevents our better understanding of the universe?

    Seems physics has stopped at the border of the uncertainty principle and the speed of light.

    Is there nothing beyond what appears in the universe?

    Glenn Borchardt

    No. The Third Assumption of Science, uncertainty (It is impossible to know everything about anything, but it is possible to know more about anything) and the Fifth Assumption of Science, conservation (Matter and the motion of matter can be neither created nor destroyed) are consupponible.

    For details see:

    Borchardt, Glenn, 2004, The ten assumptions of science: Toward a new scientific worldview: Lincoln, NE, iUniverse, 125 p. (http://www.scientificphilosophy.com)

  • M. Hasan Akyıl asked a question in NCBI:
    Ncbi 16S rRNA blast?

    After blast our sample is similarity to(%99) 5 different species. Does anyone have any idea about this situation?

  • Hussam Hikmat asked a question in C:
    How to read values from matrix using UDF programming (as initial condition)?

    I am sending this email for you hoping to help me with my UDF programming for Fluent. I have two matrices ones is the u-component velocity and the other is v-component velocity,I am trying to read the values of these two matrices and put them as an initial conditions in the domain of my model. I use the code below but I do not know how to read the values from the matrices and then write them into the model.

    #include "udf.h"
    #define pi 4.*atan(1.)


    cell_t c;
    Thread *t;
    real xc[ND_ND];
    FILE *fp;

    real r1;
    real xo1 = 0.00;
    real yo1 = 0.00;

    /* loop over all cell threads in the domain */
    /* loop over all cells */

    r1=sqrt(ND_SUM(pow(xc[0] - xo1,2.),
    pow(xc[1] - yo1,2.),
    pow(xc[2] - 0,2.)));
    /* Note xc[0] is x coordinate, xc[1] is y and xc[2] is z */

    if ( r1 != 0.0)

    fscanf(fp,"lf% %lf",&r1,&u);


    C_U(c,t) =
    C_V(c,t) =
    C_U(c,t) = 0.0;
    C_V(c,t) = 0.0;



    thanks in advance for your help

    Best regards

  • Vahid Hajiloo asked a question in Cytogenetics:
    Does any one have cytogenetic information about hyssop?

    a drug plant with scientific name of Hyssopus officinalis.


  • Anand Dev Gupta asked a question in Trihalomethanes:
    Will anybody tell me the exact procedure of formation of Trihalomethanes (THMs) by chlorination of water or in wastewater?

    pleas tell me procedure.

  • Nihat Şimşek added an answer in Materials:
    What is the compound present in rust after washing?

    Rust is form of hydrated iron(III) oxides Fe2O3·nH2O (reddish-brown material) , i grained rust and washed with DD water several times and totally removed reddish-brown precipitate from rust through better washing, finally i got blackish-brown material, it have existing magnetic property, some catalytic activity and insoluble in water, could you tell what is that blackish-brown material?

    Nihat Şimşek

    blackish-brown material is  powder of Fe and rust.

  • Anand Dev Gupta asked a question in Water Supply:
    Identify a suitable site for borewell?

    We are ​planning to dig ​a bore well now ​for the ​domestic ​drinking water ​supply. I want ​to know how to ​identify a ​suitable site ​for borewell? I ​mean what are ​the technologies ​associate with ​site identification ​of bore well?

  • N. Rishiraj added an answer in Anterior Cruciate Ligament:
    Can someone help me? What kind of neuromuscular training is the best way to prevent ACL injuries?

    I have read several articles but it is not clear what kind of training is best for the prevention of ACL injuries. 

    N. Rishiraj

    Hope the information presented below is of some use. Information is pertaining to an uninjured / intact ACL.

    Neuromuscular Training (NMT) / Preventive Neuromuscular Training (PNMT) defined:   Neuromuscular and biomechanical (neuromechanical) typically include kinematics, kinetics, and the timing and magnitude of the muscular activation and force production.(Shultz et al. 2008) Specific exercises / training can include, individually or in combination, plyometrics, strengthening and proximal control (Sugimoto et al. 2014) and balance, education, and feedback should be part of this training.(Hewett et al. 1996; Myer et al. 2005; Oñate et al. 2005; Hurd et al. 2006; Myer et al. 2006; Pollard et al. 2006; Herman et al. 2009)

    ACL Injury Mechanism:   In vivo ACL strain (causing ACL injury / rupture) is a results of  maximal load (approximately 2300 N (Yeow et al. 2008)) and timing of ground reaction forces.(Cerulli et al. 2003) A more erect / upright torso is associated with increased vertical ground reaction forces.(Blackburn et al. 2009; Shimokochi et al. 2009; Norcross et al. 2013) Anterior tibial translation increases as quadriceps contraction intensifies, (Myers et al. 2012) therefore, an upright stance in the early stages of ground contact on landing (resulting eccentric deceleration of quadriceps) seems to be associated with an ACL injury.(Decker et al. 2003; Houck et al. 2006; Pollard et al. 2007; Schmitz et al. 2007)

    As detailed below, there is much controversy regarding the efficacy of NMT / PNMT programs.

    Regardless, it is crucial to note, if NMT / PNMT programs indeed prevent ACL injury, are researchers suggesting that these programs are overcoming the inherent neuromuscular / musculo-ligment tendon-stretch reflex delay which Markolf et al (1978) and Pope et al (1979) had stated that ACL injuries occur too quickly for reflexive muscular activation; specifically intrinsic delay in activation of the hamstring muscle group to protect the ACL from injury.

    Twenty-some years later, the 1978 and 1979 information was validated by Simonsen et al. (2000) who demonstrated that the rapid concentric hamstring contraction, even during maximal activation, has only a marginal ability to protect and thus reduce ACL injury. Additional validation of the initial 1978 and 1979 data also showed there is a latency period between preparatory and reactive muscle activation that results in an electromechanical delay (Otago et al, 2007; Reed-Jones and Vallis, 2007; Lephart et al, 2002; Bell and Jacob, 1986).

    Further, as stated below (item V.2, VI.2, and VII.2) “ACL injury rates and the associated sex disparity have not yet diminished.” and “Overall ACL injury rates and the associated sex disparity have not yet diminished.” (Shultz et al, 2010, 2012, 2015, respectively).

    In addition, even in the best case scenario of NMT / PNMT are able to ‘protect the ACL’ form non-noncontact injury, numerous researchers have clearly illustrated that the benefit(s) of NMT /  PNMT programs are not long lasting – similar to physiological oerformance parameters (agility, flexibility, power, strength, etc), items IV.3, V.4, VI.3, and VII.6 below and numerous references listed below.

    Further, concern(s) remain regarding NMT / PNMT programs being able to enhance / ‘re-train:

    (1) body’s motor-learning system to react to all possible ‘ACL injury-causing’ incidences; item VI.4 below and (Pantano et al. 2010; Benjaminse et al. 2011)

    (2) the ‘protective mechanism(s)’ when the body / muscle(s) are fatigued and the risk of ACL injury is increased (items IV.2, V.5, V.6, VI.6, VI.7, and VII.7)     

    Observation from Shultz et al, 2008, ACL Research Retreat IV (ADD INFO as per below

    (IV.1) Fatigue alters lower limb biomechanical and neuromuscular factors which can lead to increasing ACL injury risk.(McLean et al. 2004; Chappell et al. 2005; Orishimo et al. 2006; Kernozek et al. 2008)

    (IV.2) The effect of fatigue is most pronounced when combined with unanticipated landings, causing substantial central processing and central control compromise. (Blackburn et al. 2008)

    (IV.3) The protective effects of ACL injury prevention training programs appear to be transient.(Graves et al. 1988; Häkkinen et al. 2003; Petibois et al. 2003)

    Observation from Shultz et al, 2010, ACL Research Retreat V

    (V.1) Intervention programs have been shown to reduce the incidence of ACL injuries.(Hewett et al. 1999; Myklebust et al. 2003; Olsen et al. 2004; Mandelbaum et al. 2005; Hewett et al. 2006; Gilchrist et al. 2008; Yoo et al. 2009)

    (V.2) Although these results are promising, ACL injury rates and the associated sex disparity have not yet diminished.(Shultz et al. 2010)

    (V.3) The ideal ACL injury-prevention program has yet to be identified.(Shultz et al. 2010)

    (V.4) The protective effects of ACL injury-prevention training programs appear to be transient.(Häkkinen et al. 2000; Petibois et al. 2003; Shultz et al. 2010)

    (V.5) Fatigue alters lower limb biomechanical and neuromuscular factors and is suggested to increase ACL injury risk. (Chappell et al. 2005; Orishimo et al. 2006; McLean et al. 2007; Benjaminse et al. 2008; Kernozek et al. 2008; Lipps et al. 2013)

    (V.6) The effect of fatigue is most pronounced when combined with unanticipated landings, causing substantial central processing and control compromise.(Borotikar et al. 2008; McLean et al. 2009)

    Observation from Shultz et al, 2012, ACL Research Retreat VI

    (VI.1) Intervention programs have been shown to reduce the incidence of ACL injuries.(Hewett et al. 1999; Myklebust et al. 2003; Mandelbaum et al. 2005; Olsen et al. 2005; Hewett et al. 2006; Gilchrist et al. 2008; Yoo et al. 2009)

    (VI.2) Overall ACL injury rates and the associated sex disparity have not yet diminished.(Shultz et al. 2012)

    (VI.3) Improvements in movement quality after 12 weeks of training do not appear to be retained once preventive training programs end.(Shultz et al. 2012)

    (VI.4) The transition from conscious awareness during technique training sessions to unexpected and automatic movement during training or game involves complicated motor control elements that might not fit in explicit learning strategies.(Beek 2000)

    (VI.5) According to Shultz et al (2010), “We must determine the performance enhancement benefits associated with regularly performing preventive training programs.”(Shultz et al. 2010)

    (VI.6) Fatigue alters lower limb biomechanical and neuromuscular factors that are suggested to increase ACL injury risk.(Chappell et al. 2005; Orishimo et al. 2006; McLean et al. 2007; Kernozek et al. 2008)   132–135,189

    (VI.7) The effect of fatigue on movement mechanics is most pronounced when combined with unanticipated landings, causing potentially adverse changes to central processing and control compromise.(Borotikar et al. 2008; Greska et al. 2012)

    Observation from Shultz et al, 2015, ACL Research Retreat VII

    (VII.1) “Injury-prevention programs have been shown to reduce the incidence of ACL injuries.”(Shultz et al. 2015)

    (VII.2) However, overall ACL injury rates and the associated sex disparity have not yet diminished.(Shultz et al. 2015)

    (VII.3) Various injury-prevention programs that incorporate elements of balance training, plyometric training, education, strengthening, and technique training or feedback have been shown to reduce incidence of ACL injury in females(Hewett et al. 1999; Myklebust et al. 2003; Mandelbaum et al. 2005; Olsen et al. 2005; Hewett et al. 2006; Gilchrist et al. 2008; Yoo et al. 2009; LaBella et al. 2011; Sadoghi et al. 2012) or alter biomechanical and neuromuscular variables thought to contribute to ACL injury.(Hertel et al. 1996; Oñate et al. 2005; Hurd et al. 2006; Myer et al. 2006; Myer et al. 2006; Pollard et al. 2006; Herman et al. 2009; Leppanen et al. 2014; Ter Stege et al. 2014; Stevenson et al. 2015)

    (VII.4) Most exercises implemented in male soccer players to prevent noncontact injuries involve eccentric exercise, balance, and specific hamstrings eccentric training.(McCall et al. 2014)

    (VIII. 5) However, data regarding the effectiveness of prevention programs to reduce ACL injuries or modify risk factors for ACL injuries in male athletes are scarce and inconclusive as to recommendations for single-legged and multidirectional maneuvers.(Alentorn-Geli et al. 2014; Sugimoto et al. 2015)

    (VII.6) Improvements in movement quality after 12 weeks of training do not appear to be retained once the program ends.(Shultz et al. 2015)

    (VII.7) Although investigation showed that the ACL is susceptible to fatigue failure during repetitive simulated pivot landings and a smaller cross-sectional area of the ACL is at greater risk for such failure (Lipps et al. 2013) it is not known if it is a single episode or multiple episodes (or both) that causes gross failure of the ACL.(Shultz et al. 2015)

  • Artur Burzynski added an answer in RID:
    Do PCR primers get fully used up during PCR?

    I believe this may be directly related to concentration of primers used, but like dNTPs, can primers also get used up fully in the course of a PCR? I am using primers for a housekeeping gene at a concentration of 10uM. I am doing these PCRs using cDNA from 5 different tissues. One of tissues does not give me any product with my housekeeping gene. The problem is further complicated by the fact that these primers are also giving me cross dimers which resolve at around 100bp, as does the amplicon for my housekeeping gene. Even a 3% gel is unable to resolve them separately. Furthermore, all my negative controls for the housekeeping gene give me a band, which is most likely the cross dimers. My opinion now is that in the case of my cDNA, all the primer might be getting used up and what i see on the gel is probably just the amplicon, whereas for my negative control, all the bands are due to the cross dimers. I have already tried increasing the annealing temperature, which does get rid of the bands but it also gets rid of my amplicons. Any suggestions, aside from designing better primers?

  • Montserrat Hernández-López added an answer in Likert Scale:
    Which Likert scale should I prefer that of 1-4, 1-5 or 1-7?

    Hi everybody!

    I'm making a questionnaire for my students about my new teaching style. My question is about the best Lickert scale that I can use in order to they evaluate some statements: 1-4, 1-5 o 1-7? I have read about this, but there are advantages and disadvantages in each of them. Can anyone help me out?

    Thank you in advance.

    Montserrat Hernández-López

    Thank you very much, Witold, Eugene and Hamid for your answers.

    I think the decisión will be taken when I pre-test my questions.