• Mariasole Da Boit asked a question:
    What is the protocol to make urine acellular?

    I need to make urine acellular to be able to store it and subsequently test it for ascorbic acid content. 

  • Ioannis D. Kostoulas added an answer:
    Is there any article about physiological responses or training in combat swimming ?

    Is there any article about physiological responses or training in combat swimming ?

    Ioannis D. Kostoulas
    Thank you Mr Mateo
  • Olaoluwa Omoniyi Olarewaju added an answer:
    What is the difference between chilling injury and non-chilling physiological disorders?

    I think chilling injury occur at different temperatures depending on the type of fruit. At what temperature is citrus fruit susceptible to chilling injury disorders and at what temperature does non-chilling disorders occur?

    Olaoluwa Omoniyi Olarewaju

    Thank you for the article... It is addresses the question and useful.

  • Jeffrey A Walker added an answer:
    Why isn’t nutrition a bigger part of conventional medical school education?
    Diet is arguably the single most important preventive measure for healthy aging because it affects the functioning of every organ in the body and is a factor both in the development of disease and in recovery.
    Jeffrey A Walker

    Yep, excellent quote to support my answer from about one year ago:

    "There are a few things we are certain about," he has said. "We know that you can’t live without food, and that if you eat too much, you get fat. There are certain essential nutrients - vitamins and minerals - that you need to have. You should make sure there is no lead or mercury or other toxins in your food. After that the knowledge base gets thinner and thinner." - David Allison, associate dean for science at University of Alabama-Birmingham


  • Juan Antonio González added an answer:
    Is there any UV light guild instrument for minimal invasion to trigger UV induced crosslinking in vivo?

    We prepared a injectable hydrogel formed by UV induced photopolymerization .We want to inject the prepolymers of the hydrogel into deep tissue and trigger the crosslinking by some UV light emiting and guild instruments with minimal invasion. Is there any instrument like this currently? If yes, can you provide the detail information or related papers to me? Thanks a lot.

    Juan Antonio González

    You can answer to Dr. Francesco Zaratti or  Dr. Eduardo Palenque from La Paz (Bolivia)- Physic Institut. The first has a good expertise in UVB and polymers

  • Guillermo Alberto Perez Fernandez added an answer:
    Does the Autonomic Nervous System still has an effect on the Heart Rate Variability of isolated hearts?

    Langerdoff isolated hart preparation

    Guillermo Alberto Perez Fernandez

    My response is yes. Hot topic.

  • Lohover Duque Sandoval added an answer:
    How to overcome overestimated MET values on International Physical Activity Questionnaire Scoring with Continuous Variable?

    International Physical Activity Questionnaire is an instrument used to assess physical activity status of population sample in age group of 20-69 years. On practical usage of the tool, the results are evaluated as MET values for domain specific MET ranges. But, when calculated for total MET values, it scores an individual on highly physical active status(min. of 3000MET min/day)

    Lohover Duque Sandoval
    Umbral altitudinal para la estimulación de la masa total de hemoglobina.
  • Atika Eddaikra added an answer:
    Metabolic water
    What happens to metabolic water?
    Atika Eddaikra

    it is good question

    in this website:

    Product of cellular respiration that is the direct consequence of reduction of oxygen.

    Metabolic water is generated when molecular oxygen serves as the final electron acceptor of electron transport chains.

    Metabolic water is chemically indistinguishable from ordinary water found in the body, being distinctive only in terms of how it is generated.

    The formation of metabolic water can be viewed as a reversal of sorts of the generation of molecular oxygen during the light reaction of photosynthesis, where water instead isoxidized (that is, versus oxygen being reduced). Indeed, the oxygen generated during photosynthesis from water is the same oxygen that is employed as the final electron acceptor of cellular respiration to generate metabolic water.

  • Marcelo Guimarães Silva added an answer:
    What is the articular cartilage fiber orientation in median zone?

    Should it be totally random or a transition part bending from deep layer to superficial layer? Is it continuous from the deep layer?  Thanks!

    Marcelo Guimarães Silva

    Hi Xuan,

    Look these papers, inside them you should find your response. Indeed, the two possibilities are applied, but I think that  a transition part bending from deep layer to superficial layer is the technique most developed (or more adapted) in this case.  

    Best regards.

    + 3 more attachments

  • Narayanan Bhattathiri added an answer:
    Does anybody know if there is a communication between tumor cells?

    I want to know whether tumor cells share their information by time passing. I were wondering if anybody could answer my question and introduce some good resources in this regard?

    Narayanan Bhattathiri

    Dear Negin

    Ahmed and Vikash have given you Scientific view points; I would like to be nonSCientific and say that Cancer cells are crazy, they will tell neighboring cells also to go crazy, for no purpose

    To be scientific again, I read long back (don't remember the reference) that even cell free filtrates from tumour cultures can turn other cells malignant, which means that even their word (contained in the solutions) harbour malignant potential


  • Chao Zhai added an answer:
    Are there any nice references discussing mechanical properties of muscles or muscular-skeletal system based on physiological observations ?

    mechanical property, muscle, muscular-skeletal system, physiology

    Chao Zhai

    Thanks Dragan. Nice suggestion.

    Kind regards,


  • Asli Baysal added an answer:
    Is hair analysis of minerals and trace elements reliable?
    Especially in alternative medicine, hair analysis often used to detect deficits and surpluses of minerals and trace elements. Are these tests reliable? What are the minerals and trace elements suitable for element analysis in hair, and what are not suitable?
    Asli Baysal

     Substances in hair have been detected weeks or months after the period of ingestion/exposure/poisoning, depending on the amount of used. Also has many advantages as a preliminary screening method for the presence of toxic substances deleterious to health after exposures in air, dust, sediment, soil and water, food and toxins in the environment. The advantages of hair analysis include the non-invasiveness, low cost and the ability to measure a large number of, potentially interacting, toxic and biologically essential elements. To find ingestion/exposure/poisoning of the compounds, hair analysis is also useful method using segmental hair analysis.

    Did you start to write article about hair analysis? If not, I can involve it..

  • Gregory Zurbay added an answer:
    What is the evidence based duration of rehab intervention for significant clinical change in patients ?

    I want to explore the duration evidence regarding the minimal detectable change clinically or statistically after rehab treatment. if someone do research so after how much time, measurement should be taken, how much intervention and time affects the physiology which bring the real change...

    Gregory Zurbay

    "The first case report of a professional footballer tearing his teres major—an extremely rare injury—is captured in a series of images published in the online journal BMJ Case Reports."

    "He returned to competition level football, with no pain and functional limitation, after 18 days."

    FYI : seems to be quite rapid recovery - considering the circumstance. Again quantification seems fluid - difficult - and possibly benefiting of reexamination.
  • Wolfgang Engelmann added an answer:
    Does anyone know anything about the influences of Moon and / or cosmic periodicities and rhythmicity on plants physiology?

    Moon gravity influences plants, animal reproduction, human behavior, etc. It is time to demonstrate to the scientific world that the cosmic and lunar periodicities significantly affects, even in the field of biological clocks.

    Since 2014 they are beginning to appear incredibly many studies about these topics before then were almost nonexistent since the nineties.

    Wolfgang Engelmann

    Have a look at:

  • Tausif Alam added an answer:
    Is there any possibility that some pancreatic islets of Langerhans might receive perfusion from mesenteric veins?
    Oral glucose seems to exert a more pronounced effect on insulin secretion than does IV glucose, an effect which is typically explained by gut hormones acting on beta cells. But an alternate explanation might be that oral glucose would show up rapidly in the mesenteric venous blood, and if this were to perfuse pancreatic islets, gut hormones would not need to be implicated. Also, some islet capillaries seem to be anatomically designed to function with low blood pressure, as if they were on the receiving end of a portal circulation.
    My question is specifically stimulated by the possibility that oral exposure to bisphenol A might lead to important physiologic effects (BPA is known to stimulate insulin secretion) even when blood concentrations of BPA are very low. This could happen if oral BPA could reach islet cells directly from the mesenteric vein, bypassing first pass metabolism in the liver.
    Tausif Alam

    "I still do not understand how this question still lingers."

    Human Psychology is an interesting thing; if a story seems reasonable, that can be enough to keep it alive even when the scientific facts do not provide any support.  ;)

  • Damien Aubert added an answer:
    Do you agree with the last classification of living things (Ruggiero et al. 2015)?

    This work really reflects a consensus of the work done on this issue?It has any connection with the theory of endosymbiosis? There is a phylogenetic relationship from its origin? Be right handle the classification by or Supergroups Kingdoms?They correlate with studies of genomes of viruses? From that point of view the classification should be done ?.
    In the images that I uploaded is a summary before 2015 classification of eukaryotes.

    Let's discuss this important topic, thanks for your contribution.

    + 2 more attachments

    Damien Aubert

    I think that Ruggiero et al.'s work is a nice attempt to stabilize the classication. I like the fact that it is not a cladist classification. Supergroups are nonsensical, they don't accurately catch the macroevolutionary leaps in eukaryotic evolution. This system of 2 empires and 7 kingdoms is a clever one, but I think there are too many phyla, especially in bacteria and in animals. The use of traditional names like Plantae and Heterokonta instead of respectively Archaeplastida and Stramenopiles is a good thing. However, I find it very strange that birds are considered reptiles ? Maybe some cladists are responsible for this absurdity.

  • John Kelly added an answer:
    Can anybody explain me how is the Exercise Physiologist profession regulated by law in UK/other countries?

    In my country (Spain) our degree (Sport Science) is not legally regulated and we are not considered by law as a health profession. For previous reason, we cannot work as exercise physiologists.

    John Kelly

     Hi Alan, absolutely right. I think the primary issue is the variability in  degree content. I did 8 years in NHS, and interviewing potential candidates for Ex Phys positions was always an enlightening experience. The quality and experience was highly variable. As bench marks, we tended to look for ACSM quals - HFI, exercise specialist etc; and higher degree. I would add that we always had very good candidates who did very well in the roles. Often they were over qual'd for some aspects. At the time, BASES wasn't up too much in the field of health (IMHO); although perhaps this position has changed since then. jk

  • Vesna Dinić added an answer:
    Why is the onset of local anesthetic delayed or even prevented when pH of media decreased like in site of infection?

    Most local anaesthetics are weak bases, with a pKa between 8 and 9, so that they are mainly but not completely ionised at physiological pH.your comments

    Vesna Dinić

    In case of infection there is acidic pH of tissue, and in that case local anesthetics are mostly in ionized form .Ionized form of local anesthetics is the one that binds to sodium channels, but non-ionizide form is the one that is important for membrane penetration. That is the reason for delayed onset of local anesthetics in site of infection. On the other hand, if you add NaHCO3 to local anesthetic, there will be more non ionizide form of anesthetic which will contribute to better membrane  penetration, and faster onset of anesthesia.  

  • Safia Belhadj added an answer:
    How can we observe Juniperus phoenicea stomata?
    It is difficult to use standard imprints method.

    Can anybody help? Thank you.
    Safia Belhadj

    Hi Biswa,

    Thanks a lot for your answer. We have developped since that time a good technique with the imprits method, but I'll for sur read your paper. Thanks again Biswa.


  • Bernard M Auriol added an answer:
    What do you think about this hypothesis of a covert path for the sound, from eardrum toward cochlea
    Eardrum comprise piezo-electric collagen fibers; do they transduct acoustical waves into electrical potentials able to reach the cochlear amplifier ?
    Bernard M Auriol

    Dear Colleague,

    I suppose there was a misunderstanding : We study the "covert path" which is electric and comes from collagen fibers piezoelectricity, for reaching through gap junctions the Deiters-cells/OHC complex at the level of the reticular lamina. We then describe the "trickystor" as a kind of Field Effect Transistor. It would interfere with the accepted mecano-electrical transduction by stereociliae, toward the inner aspect of the OHC cuticle and the prestinic structures of the OHC.


    So, what is your thoughts about these observations ?

  • Hugo F. Olivares-Rubio added an answer:
    How can I cite a site of

    The site in that I want to cite ( include the information about how to cite that record. Nevertheless, I do not understand the name of the authors. This is neccesary since I want to reference this in an article for Comparative Biochemistry and Physiology (CBP, Elsevier). Thanks.

    Hugo F. Olivares-Rubio

    Thank you very much for your kind attention. Your suggestion are important. 


  • Vasile Zoicas added an answer:
    Can Heart Rate Variability represent the ultimate marker for brain-heart interaction dysfunction leading to a pathological state?

    Dear all,

    recently many publication came up with the idea that Heart Rate Variability (HRV) derived from ECG-Blood Pressure signal could represent the ultimate marker for neurodegenerative diseases, and mood disorders. Especially, if the HRV in non linear domain seem to be the most predictive although less understood.

    What is your experience?

    Vasile Zoicas

    Dear all,

    Please allow me to share my experience on that. Agree with previous comments and I agree the HRV reflects the brain-heart interaction as part of global ANS loop but this signal is the starting point, in my opinion.

    Now, what's important, in my view, is what kind of markers we are able to extract from HRV in order to get the meaningful information? Huge amount of studies have proven correlations between physiological/pathological states and traditional LF/HF/RMSSD... markers, statistically speaking. But researchers agree as well that various limitations of the traditional methods method (5 minutes time limitation for RR pseudo-stationarity, "crafted in stone" frequency bands...) limit also the human comprehension, But the method is there and it' useful.  

    One way we took to move forward is to say: ok, we have statistically averaged markers but can we also figure out what happens in real time during the experiment? In other words, we try to figure out both physiological and emotional state of the subject and to compare with the real time markers we have recorded. This also implies novel (non linear) mathematical analysis and derived markers; and the aim is not only to find new markers but also to clearly link them to the ANS activity in both cases - real time and averaged (and in a manner that anyone can check fast).     

    One example is the attached experiment we have conducted - HRV/ANS monitoring during meditation, which raises a few questions (also posted in another thread).

  • George Zafiropoulos added an answer:
    Is there evidence that the varus in a knee with anteromedial OA appears more varus because the femoral condyle ER in the anteromedial tibial defect?

    We are looking for a publication that supports or refutes this question (see attached article by White) that shows that weight-bearing on a varus OA knee causes a large varus deformity but does not describe that the varus could be more apparent than real due to ER of the femur on the tibia.

    George Zafiropoulos

    I have the impression that in varus knee deformity the tibia is rotating externally so the defect is mainly on the posteromedial aspect of the tibial plateaux. This can be demonstrated as extreme varus angle in AP views. Usually the femora condyle is OK. Literature supporting this

    Takashi Tsujimoto and  Yoshinori Kadoya (2013). Rotational Deformity After Total Knee Arthroplasty for Varus Osteoarthritis of the Knee. Bone Joint Journal . 95-B  SUPP 34,  562

    Shuichi Matsuda , Hiromasa Miura, Ryuji Nagamine, Taro Mawatari, Masami Tokunaga, Ryotaro Nabeyama, Yukihide Iwamoto (2004). Anatomical analysis of the femoral condyle in normal and osteoarthritic knees. Journal of Orthopaedic Research 22, 104-109.

  • Yuan-Yeu Yau added an answer:
    What are the differences between industrial cane and chewing cane?

    I need to know differences between industrial cane and chewing cane in it's morphological, physical and physiological character. Both the canes come under Saccharum officinarum.

    Yuan-Yeu Yau

    "Sugarcane varieties can be placed into one of three categories according to their physical and chemical characteristics—chewing canes, crystal canes, or syrup canes".

    Please see below website for different TYPEs of sugarcanes produced by different varieties. Website is owned by University of Florida Extension (USA) at:

  • Ann M Schreihofer added an answer:
    Does anyone use the Toohey "pressure system II" or TooheySpritzer microinjection?
    We have one and love it, but have misplaced the power supply. I know its 12V, but need to know the amperage rating so I can replace it.
    Ann M Schreihofer

    I have this system and I am attaching a photo of our power supply.  Do you happen to know where I could find a reliable remote for it?  Ours works sometimes....

    Ann Schreihofer, University of North Texas Health Science Center

  • Sergio Torloni added an answer:
    Is anyone interested in hibernation research?

    I have a number of papers from a PhD colleague of mine who retired. He did the fundamental research on hibernation. He was able to identify, purify and sequence the "hibernation induction trigger".  He was able to isuccessfully induce hibernation in primates. 
    I a a physician and my area is stem cells and blood bank / clinical pathology. I am not a basic science specialist. Is anyone out there interested in continuing this research? This studies were originally funded by NASA and the US Army, so this is no joke, it is for real. 

    Sergio Torloni


    Thanks all for your interest.  Here is what I have.  Actually, Dr. Peter Oltgen is retired but still working with a colleague and has published much more current papers.  Please keep me in mind for any studies you may want to undertake. 


    + 9 more attachments

  • Esa Hohtola added an answer:
    What is the most recommended way to analyze respiration rate using LabChart software?

    I am looking for as accurately as possible method of counting the number of human breaths per minute (repiration rate) in the LabChart software.
    Option which are proposed by LabChart software (cylic measurment → Preset → Respiration - Respiratory belt with SD = 0.9) fails to find all of the breaths (there are no marks for about 30% peaks of breaths).

    It seems to me that much more precise are such option like:

    • General - Spikey shape with SD = 2.5 SD
    • Sine shape with SD = 2.0 SD

    Are there any guidelines for the size of standard deviations which should I use? Can I use Spikey shape or Sine shape method?

    I would be very grateful for any help!

    Esa Hohtola

    Hi, if you are working off-line on pre-recorded data, a simple way is to activate the piece of data of interest and choose spectrum view. Breathing data is usually clean enough to show one clear maximum in the spectrum, corresponding to true breathing frequency. No hassle with SD's. Of course, when you need the rate online, cyclic measurement is better.



About Physiology

Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system.

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