Physiology

Physiology

  • Hossein Babaei added an answer:
    When you compare mean of more than two groups by ANOVA test, which post-test you recommend to find different groups ?

    When you compare mean of quantitative data (for example: blood pressure or heart rate) in more than two groups by ANOVA test, and get significant difference (p< 0.05), which post-test should be used to find different groups.

    Hossein Babaei · Tabriz University of Medical Sciences

    Thanks every body.

  • Lance Dworkin added an answer:
    Why is hydrostatis capillary pressure in glomeruli so high (55 mm of Hg)?

    Capillary hydrostatic pressure in intestinal villous capillaries is 15 mm of Hg while it is 55 in glomeruli capillaries.

    Lance Dworkin · Alpert Medical School - Brown University

    Glomerular capillary hydraulic pressure is a better term because the fluid in the capillaries is not static but flowing.  The value for glomerular capillary hydraulic pressure of about 55 mmHg comes from experiments in rats and squirrel monkeys that have glomeruli on the surface of the kidney in which capillaries were punctured and pressure directly measured.  It is assumed to be similar in other mammalian species like man.  There must be some drop in pressure moving down the capillary from the afferent to the efferent arteriole for blood to flow, but it is probably small.  In contrast, the plasma protein concentration and corresponding oncotic pressure inside the capillary rises significantly moving from the afferent to the efferent arteriole.  As a result the net ultrafiltration pressure, which is the difference between the hydraulic pressure (favoring filtration) and the plasma oncotic pressure (opposing filtration) drops from 10-15 mmHg near the afferent end of the capillary network to zero or close to zero (depending primarily on plasma flow rate) by the termination of the glomerular capillaries at the origin of the efferent arteriole. 

    Another factor contributing to the high rate of fluid movement across the glomerular capillary wall is the hydraulic conductivity of the capillary, which is significantly greater than other capillaries as well.   

  • Maria Bettencourt Pires added an answer:
    Who knows the function of left and right auricle?
    Seeking an answer to this.
    Maria Bettencourt Pires · New University of Lisbon

    As an Anatomist, I usually teach my students that every part of the body has it's own importance and function, and that our bodies were build with no redundancy of parts. Even when we don't know or don't understand the function of an organ, this doesn't mean that it is useless. (Think of the appendix, that used to be considered as useless,  for many years, leading to so-called "preventive" appendicectomies in the near past, until immunological studies and cohort studies, led to the conclusion that it is a precious chamber with rich content of cytotoxic and oncotoxic cells, and that it is useful preventing intestinal cancer...)

    In the case of the auricles, cardiac surgeons will tell you that it is a precious surgical help in cardiac valve replacement surgery, because it has the exact shape that will help the surgeon to slip his finger tip and stretch the region for the open-heart valve replacement. (This, of course, was the information I got, some 30 years ago, when open-heart surgery was currently performed, before the more modern cardiac surgical approaches...)

    In physiological, and more serious terms, these small antechambers, placed in a strategical region of the atrial main chamber, may well play an important role as an spare reserve of blood content, or, to prevent turmoil of the atrial blood content, in specific case of overloading.

    I am not, of course sufficiently documented in terms of cardio-vascular physiology, nor surgery, but I thought that my "innocent" comments as a general anatomist, might be helpful in this context of your interesting question.

  • Michael Nordine added an answer:
    Using NIRS underwater?

    Has anyone any experience/advice for measuring central/distal hemoglobin via NIRS (NIRO-200, Hamamatsu Photonics) during water immersion? Will the electrodes function underwater? Will immersion destroy the electrodes? Before I test this out, and potentially make a very expensive mistake, just wondering if anyone has tried this before.

    Thanks

    Michael Nordine · Charité Universitätsmedizin Berlin

    Thanks Hui!

  • Mamta Singh added an answer:
    Which parameters could be measured to prevent an epilepsy seizure ?

    I'm looking for chemical or physiological parameters (which can be measured) that change minutes or seconds before an epilepsy crisis. In other terms, what are the chemical, biological and physiological changes that occur just before an epilepsy crisis ?

    Mamta Singh · All India Institute of Medical Sciences

    On EEG, focal rhythmic delta-theta may predict an oncoming seizure as may an increase in the density of interictal spikes.

  • Austin Johnson added an answer:
    Which shock scores commonly used by emergency medical personnel?

    Besides the well known, shock index, are there any other commonly used clincal indices for the assessment of shock, particulalry hypovolemic/hemmorrhagic shock? If so, how are they calculated, and why are they prefered over the shock index?

    Austin Johnson · University of California, Davis

    In addition to what has been mentioned:

    There is the revised trauma score which is actually calculated in the large trauma registries that are kept at level 1 trauma centers: RTS=0.9368(GCS)+0.7326(SBP)+0.2908(RR)

    The Denver TOF (Trauma Organ Failure) Score to predict multi-organ failure during hospitalization. Annals of Emergency Medicine. Volume 62, Issue 4, Supplement, Pages S4–S5, October 2013

    During clinical practice most people work off the actual vital signs, physical exam, and bedside ultrasound findings. NIRS is still experimental within the emergency department, no standard of care.

  • Vic Cherikoff 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.
    Vic Cherikoff · University of Sydney

    Medical training is a reductionist science. Disease symptoms are X, Y and Z which means A or C is the most likely cause. Treat with the most promoted pharmaceutical or the one from the company that gives out golf clubs or club memberships or runs conferences in exotic places. It doesn't matter much if the drug doesn't work because most people get better in the morning anyway. Grant funding for reductionist projects is easy to get because the projects are usually sexy - there's even fun names like nutrigenomics, epigenetics and there are also machines that go 'PING'. Imagine being able to adjust a few genes and make a symptom or two disappear. Too bad it is hugely costly and only available to the extremely wealthy. At least if they are grateful they contribute lots of money to more research which is way better than running, walking, wearing a pink nose or having a BBQ to raise awareness and a few dollars for research.

    Nutrition on the other hand is a wholistic science. People have their own choice as to eating a good diet or a bad one. They empower themselves if they have the correct knowledge and motivation to get healthy. Grant funding is difficult to get because it is just not as sexy and what if people find out that dietary calcium is not actually essential for healthy teeth and bones but magnesium is more so? There's little magnesium in dairy products so that won't do. The dairy industry will have nothing positive to say about a product designed for calves, not humans. And then there's that study which linked drinking milk with the expression of cancer and the regression of cancer when the intake of dairy was abandoned. Oops.

    Another problem is that we know a bunch of diseases which we label because of a collection of symptoms. It is a problem when diseases of nutrition have changing or non-specific symptoms. That just won't do. 100 trillion cells can't be that complex. All those enzymes. Humbug! And now we have to learn about phytochemicals, antioxidants, anti-inflammatories, enzyme regulators. Too much. What do you mean lifestyle medicine? Just take Statins, Metformin, allopurinol, aspirin and go away. Metaflammation? System wide??? No. It's not happening. Help!

  • Subrahmanyam Vangala added an answer:
    More smart people are less successful

    Why more smart people are less successful in workplace and achieving their goals. In contrast, less smart people are more successful, in general? is it true and why?

    Subrahmanyam Vangala · Advinus Therapeutics

    I believe everyone is smart.  You need to define what is success first ?  Becoming a CEO? Earn a lot of money ?  Or become a celebrity ? Great sports player ?  Individual success depends on realizing one's own talents and using them to get ahead in life.  If you do not know your own strengths and weaknesses, that means you are not smart.  But most smart people know what they are good at and focus on their strengths, not on their weaknesses.

  • Walter Golf added an answer:
    After the infusion of glucose to a Wistar rat, how much time does it take for the pancreas to start secreting insulin?

    Please refer your answers to reliable reference(s).

    Walter Golf · Justus-Liebig-Universität Gießen

    Hallo,

    I remembered the work of Landgraf 1971, published in Proc. Natl. Acad Sci, where he wrote:

    RESULTS

    The effects of glucose (Figs. 1 and 2)

    Insulin release induced by 20 mM glucose was multiphasic.

    The initial phase began after a short delay (45 see) and

    reached its maximum within 2.5-3 min. After a transient decline

    at a low point at 7 min, a second, gradually rising, response

    occurred; this response disappeared upon cessation of

    the glucose stimulus. Prestimulatory insulin levels were

    reached within 4 min after cessation of glucose perfusion.

    This biphasic response is well known from other studies with

    perfused rat pancreas (4) and from in vivo studies with dog

    (5) and man (6).

    Proceedings of the National Academy of Sciences

    Vol. 68, No. 3, pp. 536-540, March 1971

  • Abdul Mannan Baig added an answer:
    What can you say about the pharmacology of the agonist/antagonist?

    I am looking at the mechanism of action of a GPCR agonist on hippocampal physiology. An antagonist for the receptor does not block the peak agonist-effect, but changes irreversible effect to reversible. What can we say about the pharmacology of the agonist/antagonist?

    Abdul Mannan Baig · Aga Khan University, Pakistan

    If you name the drugs I may look into any covert partial agonist or antagonist effects that as referred earlier maybe the reason.

  • Sean Patterson added an answer:
    Child vaccinating against HPV (human papillomavirus)

    Hello dear community,
    I have a question for all biologists, physiologists, physicians, pharmacists, gynecologists

    My sister is 12 years old and the doctors say they should be vaccinated against HPV (human papillomavirus), not later than in two months.
    My question is, I have read in various sources that vaccination is harmful and can cause cancer. I'm looking for the truth, I know that the only vaccination against human papillomaviruses, which Cervical cancer can prevented. I want to know from you what is true and like I want to be able to have evidence to understand that.

    I hope for a fast answer

    Thank you,

    Petr Kirpeit

    Sean Patterson · National University of Cuyo

    Hi Petr.

         In my experience you have opened a can of worms here, but since I have recently been looking at the same question I will share my observations. I assume that the anti-HPV is not compulsary in your country, in which case the question is the same as for any elective treatment - do the risks outweigh the benefits? Consider the question from each side, taking into account what we know and what we don't know.

    The risks

         (1) All vaccinations have a risk. Just as for any other pharmaceutical, there exists the possibility of an adverse reaction. If you wish to examine the risks associated with the various anti-HPV vaccines (basically two), the VAERS (vaers.hhs.gov) site run by the Center for Disease Control in the U.S.A has a great deal of information on the subject. Be warned, it is not very user friendly. Vaccination has a low (generally a few cases per 100,000 vaccinations) association with severe or fatal side effects. Unfortunately, the anti-HPV vaccines are amongst the worst for severe side-effects, including cervical cancer. Bear in mind that this is correlational data, not causal.

         (2) There is a question of moral hazard. Studies have shown that people who have received the HPV vaccine are more likely to engage in high risk sexual behaviour than those who have not. HPV is the most prevalent sexually transmitted disease (STD), but not the only one and the protection provided by the vaccine is partial - especially as it is directed against only 4 of the 116 (last time I checked) serotypes. The vaccine appears to provide at least some protection against other serotypes, but the evidence suggests that most of the strains are capable of producing the same effect as the serotypes used in the vaccines.

         (3) Finally, these vaccines have been given given fast-track approval by the FDA, not full approval. This means that they have not been subject to the rigorous evaluation of either their safety or efficacy that other vaccines are required to go through.

    The benefits

         (1) Cervical (and anal and throat) cancer is not the only condition caused by HPV. Horribly disfiguring genital warts, as pointed out by William Johnson above, are also a potential consequence of infection, although the occurence of this condition is most common in homosexual men (substantially less common in women and heterosexual men).

         (2) HPV is the most common reported STD and barrier methods have only partial if any effect.

         (3) While HPV infection is neither necessary nor sufficient for the development of cervical cancer, 90% of cases test do positive for the presence of HPV and the vaccine is clearly effective at reducing the infection rate (of the 16 and 18 serotypes and at least some others).

    The doubts

         (1) HPV is transmitted mostly, if not exclusively, by sexual contact. The duration of the efficacy of the vaccine is not known, but is quoted as 5 years (although this may have changed now). Vaccinating many years before the initiation of sexual activity is of dubious value.

         (2) The 16 and 18 serotypes appear to have been selected for being the most common amongst Caucasian females in the U.S.A. It is known that these are not the most common serotypes amongst, for example, African Americans. The usefulness of the vaccine might depend very much on which serotypes are most prevalent in your environment (Czech Republic?).

         (3) The development of cervical cancer goes through stages, with the vast majority resolving spontaneously in the early stages (1-2 of 4). Most of the later stages are picked up by pap-smears and it is amongst the most treatable of cancers if it is caught before it advances. It has been argued that pap-smears after initiating sexual activity make the vaccination unneccesary in developed countries where compliance with regular check-ups is high.

    In summary, the risk-benefit analysis depends very much on your own situation. It is tightly linked to very personal questions regarding sexual behaviour and the age at which it starts. There is no general answer, but I would ask any doctor that recommended vaccinating a 12 year old for a STD precisely why?

  • Paresh Chandra Ghosh added an answer:
    Is there a direct correlation between a particular stimulus and an effector response?

    Is there the possibility to modulate a stimulus (by changing frequencies and duration) and set a direct relationship between that stimulus and a certain muscle AP? Telling it otherwise, applying the same stimulus (maintaining the same frequency and duration), again and again, on the same alpha neuron, I will have the same effector contraction (with plenty of time to relax between stimulus)? If the answer is yes, it is possible to build a matrix with different stimulus and correlated muscles AP's?

    Dear Sir

    If i have understood your question properly then answer is yes. all physiological parameters are responded similar to stress& strain relationship. it is simple linear positive cor-relationship. It is true in your case also. pcg,Chennai

  • Menakshi Bhat added an answer:
    Can anyone help me to know the enzymes that affect renal function in rats treated with the extract flaxseed (physiological and histological)?

    I need to research have been published in this topic

    Menakshi Bhat · Université de Montréal

    In addition to the obove written answers you can also detect the ACE (Angiotensin-converting enzyme) which is observed to be increased during renal failures. It is one of the major and important enzymes detected during renal failures.

    A simple, rapid, highly sensitive and reproducible assay for angiotensin-converting enzyme in untreated serum can be done. It is based on the conversion of the substrate, hippuryl-L-histidyl-L-leucine (5 mM in 0.1 M K phosphate, pH 8.3-0.3 M NaCl) to hippurate and L-histidyl-L-leucine, which can be is quantified spectrofluorimetrically. Also ACE can be detected using western blotting or quantitative PCR method. 

  • Alejandro Díaz-Moscoso added an answer:
    Spouse working in the same lab or environment

    Let me put earlier question in this way: Earlier question was Should researcher marry another researcher;

    My alternate question is that would you prefer or not prefer your spouse working in your lab or in your close vicinity?

    Alejandro Díaz-Moscoso · Universitat Rovira i Virgili

    There is a very good historical example: Pierre and Marie Curie worked together towards the nobel prize (and also their daughter did the same with her husband) and they are recognised as a really in-love couple (even after his accidentally death).

    In my personal case, me and my wife (recently married) have been working in as a couple for 10 years, and everything is OK. We started in the same lab and have managed to move together (always working in the same city) through e different cities in 2 countries. We never needed to "do deals" with anyone, each of us have managed until now to get our own places and funding. It may need some concessions, but like any other relationship and, if the relationship is well based, you will find the way to succeed in your careers to the best of your possibilities and will be no jealousy for the other achievements, but proud.

  • Eugenio Bertelli 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.
    Eugenio Bertelli · Università degli Studi di Siena

    I still do not understand how this question still lingers. Let's try to see this reasoning hemodynamically. In order for the mesenteric  vein blood to go to the pancreas you have two possibilities: 1) the entire pancreas is supplied by venous blood 2) the exocrine pancreas is supplied by the regular arterial blood and the endocrine by the venous blood. The first option is impossible as many arteries distribute within the pancreas and because in vivo arteriography demonstrate a parenchymal phase soon after the injection of the arteries and before the mesenteric vein becomes visible. Now option number two: apart from the fact that dissection studies never showed different veins coming from the exocrine pancreas and from the endocrine pancreas (and in this case we should say going to the endocrine pancreas), you should always consider that the blood moves from a region of higher pressure to a region with lower pressure. To fulfill this main issue you should postulate that within the pancreas you should have hundreds of thousands of small regions (islets) with low blood pressure embedded in a vast area where the pressure is higher. In other words each islet should be completely sealed from the blood circulating within the exocrine part. And this is simply not true as many corrosion casts studies have showed or even Bonner-Weir papers have demonstrated.

  • Emmanuel Gonzalez asked a question:
    Construction hazard identification--how does the human brain work?

    Is there are psychological and physiological explanation on how a person effectively identifies a certain hazard on site? Is there a mathematical model that can describe this?

  • Thomas W Stief added an answer:
    Why PT or INR is a better measure for evaluating the effect of vitamin K on coagulation process than PTT?

    As we know, vitamin K is essential for the formation of factors 2,7,9,10 in the coagulation cascade, which factor 7 participates in extrinsic pathway, factor 9 participates in the intrinsic pathway and factors 2 and 10 participate in the common pathway
    From the above information we can say that vitamin K is essential for both extrinsic and intrinsic pathways. But as we know, for evaluation of effect of vitamin K on coagulation process, we measure PT or INR.

    Thomas W Stief · Universitätsklinikum Gießen und Marburg

    Heparin or LMWH are very common drugs within the Hospital. Both influence intrinsic coagulation. The PT is not influenced by Heparin because the reagent contains polybrene, an Heparin Inhibitor.

  • subhransu sekhar Mishra added an answer:
    Do the anti-diabetic herbal products have insulin/insulin like compounds?
    Many studies have demonstrated that herbal extracts can reduce glucose concentrations. The mechanism underlying this effect is still to be clarified. To best of my knowledge, no insulin/insulin like compounds have been described. What do you think about?
    subhransu sekhar Mishra · Biotechayur

    If required Insulin  for the treatment of type-1 or type-2 diabetes ,then there is no better option then Insulin therapy alone but there are some herbs which if administered along with insulin ,then act as an adjuvant  .Those herbal extracts can decrease the daily total dose of Insulin .One example which I have observed is about Momordica charantia extract . On the long term I have observed that this can decrease the total requirement of insulin . Some patients even found to be now without insulin(but this number is very few) .

  • Heather J. Nuske added an answer:
    Online MATLAB courses

    Hello there! Can anyone recommend online courses for Matlab? I want to learn how to process physiological data (HR, RSA and SCR with Biopac equipment) in MATLAB. Which company/course would suit this best? I found that MathWorks have many courses online, but I am not sure which ones to take. I would be very grateful for any advice! Thanks!

    Heather J. Nuske · La Trobe University

    Thanks so much Saman! Very helpful!! :)

  • Aditya Arya added an answer:
    Where can I find the protocols for mitochondrial depletion with ethidium bromide?

    Mitochondrial stress induction protocols.

    What about other protocols for oxidative stress induction by using H2O2? 

    Aditya Arya · Defence Research and Development Organisation

    http://www.sciencedirect.com/science/article/pii/S0378427407000793

  • Diane Johnson asked a question:
    Are there any relevant papers that concern the physiological, metabolic and notational demands of firstly dance and secondly netball?

    Would like to review literature on these events

  • Damian G Kelty-Stephen added an answer:
    What are the physiological mechanisms involved in cognitive impairment?

    What are the physiological mechanisms involved in cognitive impairment?

    Damian G Kelty-Stephen · Grinnell College

    The answer may depend, unfortunately for compact answers in science or here in RG, on what sort of impairment you are interested in.  Impairment following insult to neural tissue?  Or impairment over the longer-haul of development over the lifespan? The answer can be more surprising as you move from the double-dissociation options for the former to the more complex phenomena of the latter.

    It is often quite straightforward to implicate physiological mechanisms within the closely related neural circuitry, as Abhijit's helpful answer points out. However, there a lot of newer findings showing the effects of things we think of as farther "downstream" and more as "outputs." Curiously, simple experiential habits like physical exercise, diet can be among the best predictors of impairment over the lifespan. I share the following three that I've been looking at recently:

    http://www.ncbi.nlm.nih.gov/pubmed/25177186

    http://psycnet.apa.org/journals/hea/22/6/559/

    http://library.mpib-berlin.mpg.de/ft/ul/UL_Limits_2001.pdf

    The cropping-up of nonobvious causes now with more data, more diverse scientists, and more ways to measure cognitive performance seems symptomatic (to me and my friends, biased though we all may be) of cognitive phenomena requiring systems-y explanations like those increasingly pursued in biological sciences.

    Best wishes,

    Damian

  • Zhuo Shao added an answer:
    How to accurately determine Postnatal Day 6 (P6) of mice to evaluate angiogenesis at P6?

    I am working in the field of angiogenesis and I analyse physiological angiogenesis in mouse retina. I always have to analyse angiogenesis at P6 and therefore it is really important to know when the pups are born, so that one can accurately determine P6.  I usually check for the pups twice or thrice a day, but I see variability in my result and most probably it is due to not accurately determining the birth date of pups. Could anyone give me suggestions how can I accurately determine when the pups are born? Thanks ahead.

    Zhuo Shao · McGill University

    I agree with Florian and Agnieszka, even you know the exact age, there will still be variation on retinal angiogenesis. Weight gain plays a critical role in retinal vascular development. You can refer to the following paper on this:

    Postnatal weight gain modifies severity and functional outcome of oxygen-induced proliferative retinopathy.

    Stahl A, Chen J, Sapieha P, Seaward MR, Krah NM, Dennison RJ, Favazza T, Bucher F, Löfqvist C, Ong H, Hellström A, Chemtob S, Akula JD, Smith LE.

  • Thamir Ismail added an answer:
    Final concentration of 100% ethanol is 1% (50ul in 5ml) in cell culture dish, having 5ml cell suspension. Does it affect the cell line?

    I have cultured HCT-15 (Adherent), colon cancer cells in 35mm cell culture dish, having 5ml of RPMI-1640 media. I have to treat these with 10uM of a drug. The stock concentration of drug (C1) is 1mM, dissolved in 100% ethanol. So i have to add 50ul of the stock solution of drug to the cell culture dish, where according to C1V1=C2V2, it final concentration (C2) becomes 10uM. As the drug has been dissolved in ethanol, it means that i have added 50ul of ethanol to 5ml of cell culture media, where its final concentration becomes 1% (50ul per 5ml). The desirable effect of drug is induction of apoptosis. So I want to know whether besides the desirable effect of drug, this concentration of 100% ethanol has some influence on cell line or not? No doubt that any effect of ethanol is undesirable. If anyone help me in this regard, I will be grateful. Provision of reference will be highly appreciated. 

    Thamir Ismail · University of Liverpool

    I 100% agree with Tognolini.  Its better to try different concentrations of ethanol treatment as some of the cell lines are happy up to 2% ethanol.  But, to be on the safe side, 0.5% is safe to use.

  • Gunjan Pandey asked a question:
    "L-DOPA methyl ester" physiological role

    Dear Authors, 

    Could you please point me in the right direction to find out the natural occurrence and physiological role of L-DOPA methyl ester?

    Many thanks for your help.

    regards,

    gunjan

  • Does someone know of a research supporting the teaching of breathing in through the nose and out through the mouth?

    We are putting together an online CBT intervention for children and adolescents with functional abdominal pain. Many in our team have been taught to breathe in through the nose, out through the mouth. I am wondering whether there is any empirical evidence supporting this teaching. Thanks in advance!

    Amandio Aristides Rihan Geraldes · Universidade Federal de Alagoas

    "Nasal breathing (as opposed to mouth breathing) increases circulation, blood oxygen and carbon dioxide levels, slows the breathing rate and improves overall lung volumes " Swift, Campbell, McKown 1988 Oronasal obstruction, lung volumes, and arterial oxygenation. Lancet 1, 73-75

    "The internal nose not only provides around 90% of he respiratory system air-conditioning requirement but also recovers around 33% of exhaled heat and moisture. Elad, Wolf, Keck 2008 Air-conditioning in the human nasal cavity. Respiratory Physioolgy and Neurobiology 163. 121-127

    "The nasal cycle, which is part of an overall body cycle, is controlled by the hypothalamus. Sympathetic dominance on one side causes nasal vasoconstriction of the ipsilateral turbinate, while parasympathetic dominance on the other causes nasal vasoconstriction of the contralateral turbinate. Increased airflow through the right nostrii is correlated to increased left brain activity and enhanced verbal performance, where as increased airflow through the left nostril is associated with increased right brain activity and enhanced spatial performance."
    Shannahoff-Kalsa, 1993 The ultradian rhythm of alternating cerebral hemispheric activity. International journal of Neuroscience 70, 285-298

    "During exercise, nasal breathing causes a reduction in FEO2, indicating that on expiration the percentage of oxygen extracted from the air by the lungs is increased and an increase in FECO2, indicating an increase in the percentage of expired air that is carbon dioxide". Morton, King, Papalia 1995 Comparison of maximal oxygen consumption with oral and nasal breathing. Australian Journal of Science and Medicine in Sport 27, 51-55

  • Atena Eslami added an answer:
    Does anyone know whether there is a site that had transparent pictures of salty glands in plants or not?
    I have been accumulating some papers for a seminar, but unfortunately I don't have enough pictures of that. Can anyone help me?
    Atena Eslami · Lorestan University

    Hi dear

    thanks for your answer but would you please send me the chapter which related to the salty glnds?

  • Adam R Kennedy added an answer:
    What will happen if someone to be in darkness for 10 years?

    Physiological changes

    Adam R Kennedy · Cytokinetics

    The answer to this question would require several assumptions.  Keeping someone in darkness for 10 years would require a rather sadistic psychology on the part of the captor and the likelihood of that being the only negative aspect of their incarceration is very low.  However, assuming that this person was being kept otherwise healthy, well fed, entertained (isolation would lead to severe psychological distress) and sheltered from heat or cold, the main effects would be on the pigmentation of their skin (skin color would lighten) and their ability to produce vitamin D which would lead to soft bones, possibly rickets.  The mammalian circadian rhythm is 26-27 hours long, so it would be possible to change the persons circadian rhythm if all other timed stimuli were removed or provided randomly.  Sleep patterns may be disrupted (outsize of the timing), with less sleep in sibling bouts (this happens in totally blind people).  

  • Miranda Yeoh added an answer:
    Have you tried meditation for stress removal, and what is its effect on your work, teaching and research?
    Meditation has physiological and psychological effects that include reduced respiration rate, decreased heart rate, changes in brain wave patterns, lowered stress, improved emotional well-being, blood pressure and working memory. So, have you tried meditation? What effects have you observed?
    Miranda Yeoh · Kolej Matrikulasi Selangor, MALAYSIA (Selangor Matriculation College)

    Very true, dear Kuldeep and friends: 'Meditation helps in restoring energy, thinks positively, increases concentration and relaxes both body and mind'.  Let me share too.

  • Irina Pechonkina added an answer:
    Why do we prefer things that are harmful for our bodies including sugars, carbohydrates and avoid things with beneficial effects like exercise?
    Harmful effects are associated with sweet taste, beneficial effects have no preferred taste.
    What do you think about?
    Irina Pechonkina · Math and Physical Lyceum

    An interesting article by American Psychological Association "Emotional distress regulation takes precedence over impulse control. If you feel bad, do it" http://www.apa.org/pubs/journals/releases/psp80153.pdf

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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