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Sample records for human physiological body

  1. Human physiology in space

    NASA Technical Reports Server (NTRS)

    Vernikos, J.

    1996-01-01

    The universality of gravity (1 g) in our daily lives makes it difficult to appreciate its importance in morphology and physiology. Bone and muscle support systems were created, cellular pumps developed, neurons organised and receptors and transducers of gravitational force to biologically relevant signals evolved under 1g gravity. Spaceflight provides the only microgravity environment where systematic experimentation can expand our basic understanding of gravitational physiology and perhaps provide new insights into normal physiology and disease processes. These include the surprising extent of our body's dependence on perceptual information, and understanding the effect and importance of forces generated within the body's weightbearing structures such as muscle and bones. Beyond this exciting prospect is the importance of this work towards opening the solar system for human exploration. Although both appear promising, we are only just beginning to taste what lies ahead.

  2. Opportunities and constraints of presently used thermal manikins for thermo-physiological simulation of the human body

    NASA Astrophysics Data System (ADS)

    Psikuta, Agnes; Kuklane, Kalev; Bogdan, Anna; Havenith, George; Annaheim, Simon; Rossi, René M.

    2016-03-01

    Combining the strengths of an advanced mathematical model of human physiology and a thermal manikin is a new paradigm for simulating thermal behaviour of humans. However, the forerunners of such adaptive manikins showed some substantial limitations. This project aimed to determine the opportunities and constraints of the existing thermal manikins when dynamically controlled by a mathematical model of human thermal physiology. Four thermal manikins were selected and evaluated for their heat flux measurement uncertainty including lateral heat flows between manikin body parts and the response of each sector to the frequent change of the set-point temperature typical when using a physiological model for control. In general, all evaluated manikins are suitable for coupling with a physiological model with some recommendations for further improvement of manikin dynamic performance. The proposed methodology is useful to improve the performance of the adaptive manikins and help to provide a reliable and versatile tool for the broad research and development domain of clothing, automotive and building engineering.

  3. MRI-based three-dimensional thermal physiological characterization of thyroid gland of human body.

    PubMed

    Jin, Chao; He, Zhi Zhu; Yang, Yang; Liu, Jing

    2014-01-01

    This article is dedicated to present a MRI (magnetic resonance imaging) based three-dimensional finite element modeling on the thermal manifestations relating to the pathophysiology of thyroid gland. An efficient approach for identifying the metabolic dysfunctions of thyroid has also been demonstrated through tracking the localized non-uniform thermal distribution or enhanced dynamic imaging. The temperature features over the skin surface and thyroid domain have been characterized using the numerical simulation and experimental measurement which will help better interpret the thermal physiological mechanisms of the thyroid under steady-state or water-cooling condition. Further, parametric simulations on the hypermetabolism symptoms of hyperthyroidism and thermal effects within thyroid domain caused by varying breathing airflow in the trachea and blood-flow in artery and vein were performed. It was disclosed that among all the parameters, the airflow volume has the largest effect on the total heat flux of thyroid surface. However, thermal contributions caused by varying the breathing frequency and blood-flow velocity are negligibly small. The present study suggests a generalized way for simulating the close to reality physiological behavior or process of human thyroid, which is of significance for disease diagnosis and treatment planning. PMID:23999383

  4. I Sing the Body Electric: Students Use Computer Simulations To Enhance their Understanding of Human Physiology.

    ERIC Educational Resources Information Center

    Coleman, Frances

    1998-01-01

    Describes how computer simulations can enhance students' learning of physiology. Discusses how computer models enhance experimentation; using computer modeling in high school science; three steps in students' writing of a simulation; and the value of simulations. Lists six software vendors who offer packages on the PC or Macintosh platforms. (AEF)

  5. Corrosion Behaviour of Nitrogen-Implantation Ti-Ta-Nb Alloy in Physiological Solutions Simulating Real Conditions from Human Body

    NASA Astrophysics Data System (ADS)

    Drob, Silviu Iulian; Vasilescu, Cora; Drob, Paula; Vasilescu, Ecaterina; Gordin, Doina Margareta; Gloriant, Thierry

    2015-04-01

    We applied a new nitrogen-implantation technique (trademark Hardion+) using a source of nitrogen ions, electron cyclotron resonance that assures higher energy and deeper implantation than the conventional techniques. The N-implantation surface of the new Ti-25Ta-25Nb alloy was analyzed as follows: for the phase identification by x-ray diffraction (XRD) in a glancing geometry (1°); for the hardness by the nano-indentation method; for the corrosion behaviour in Ringer solutions of different pH values (simulating the real conditions from the human body) by cyclic and linear polarization, electrochemical impedance spectroscopy and the monitoring of the open circuit potentials and corresponding potential gradients. XRD pattern was indexed with face-centred cubic TiN compound partially substituted with TaN and NbN. The hardness increased about 2 times for the N-implantation alloy. The implantation layer had a protection effect, increasing the corrosion and passivation potentials and decreasing the tendency to passivation and passive current density, due to its compactness, reinforcement action. The corrosion current density and rate decreased by about 10 times and the polarization resistance increased by about 2 times, indicative of a more resistant nitride layer. The porosity was much reduced and the protection efficiency had values closed to 90%, namely the implantation treatment led to the formation of a dense, resistant layer. Impedance spectra showed that the capacitive behaviour of the N-implantation alloy was more insulating and protective. An electric equivalent circuit with two times constants was modelled.

  6. Mind and Body: Concepts of Human Cognition, Physiology and False Belief in Children with Autism or Typical Development

    ERIC Educational Resources Information Center

    Peterson, Candida C.

    2005-01-01

    This study examined theory of mind (ToM) and concepts of human biology (eyes, heart, brain, lungs and mind) in a sample of 67 children, including 25 high functioning children with autism (age 6-13), plus age-matched and preschool comparison groups. Contrary to Baron-Cohen [1989, "Journal of Autism and Developmental Disorders," 19(4), 579-600],…

  7. Physiologic regulation of body energy storage

    NASA Technical Reports Server (NTRS)

    Pitts, G. C.

    1978-01-01

    Both new and published data (rats, mice, and human beings) on three parameters - fat mass, fat-free body mass (FFBM), and total body mass in some cases - are evaluated. Steady state values of the parameters are analyzed for changes in response to specific perturbing agents and for their frequency distributions. Temporal sequences of values on individuals are examined for evidence of regulatory responses. The results lead to the hypothesis that the FFBM is regulated, but probably not as a unit, and that mass of fat is regulated with a high priority near the range extremes but with a much lower priority in the mid-range. Properties and advantages of such a mechanism are discussed.

  8. Multichannel Human Body Communication

    NASA Astrophysics Data System (ADS)

    Przystup, Piotr; Bujnowski, Adam; Wtorek, Jerzy

    2016-01-01

    Human Body Communication is an attractive alternative for traditional wireless communication (Bluetooth, ZigBee) in case of Body Sensor Networks. Low power, high data rates and data security makes it ideal solution for medical applications. In this paper, signal attenuation for different frequencies, using FR4 electrodes, has been investigated. Performance of single and multichannel transmission with frequency modulation of analog signal has been tested. Experiment results show that HBC is a feasible solution for transmitting data between BSN nodes.

  9. Human whole body cold adaptation

    PubMed Central

    Daanen, Hein A.M.; Van Marken Lichtenbelt, Wouter D.

    2016-01-01

    ABSTRACT Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold. PMID:27227100

  10. Human whole body cold adaptation.

    PubMed

    Daanen, Hein A M; Van Marken Lichtenbelt, Wouter D

    2016-01-01

    Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold. PMID:27227100

  11. Columbus payload requirements in human physiology

    NASA Astrophysics Data System (ADS)

    Stegemann, Juergen

    1993-03-01

    Most of the biological feedback loops in the human body are interrelated. This means that several different parameters have to be recorded simultaneously to understand the interrelationship of different subsystems within the body when fast and slow adaptation processes are to be studied. This determines the requirements for the payload in the Columbus module. In 1988 ESA asked some European scientists in different fields of physiology to provide a 'science study' for the Columbus payload requirements. Their report was the basis of a phase A study completed in December 1991, concerning the 'ANTHROLAB', a laboratory that covers all presently known research challenges in this area. Anthrolab is more or less an improvement of the Anthrorack to be flown on the German Spacelab mission D-2 and on the Columbus precursor flight E-1. Beside the present Anthrorack design, Anthrolab will also provide subelements for vestibular, neurophysiological, and biomechanical research.

  12. Interoception: the sense of the physiological condition of the body.

    PubMed

    Craig, A D

    2003-08-01

    Converging evidence indicates that primates have a distinct cortical image of homeostatic afferent activity that reflects all aspects of the physiological condition of all tissues of the body. This interoceptive system, associated with autonomic motor control, is distinct from the exteroceptive system (cutaneous mechanoreception and proprioception) that guides somatic motor activity. The primary interoceptive representation in the dorsal posterior insula engenders distinct highly resolved feelings from the body that include pain, temperature, itch, sensual touch, muscular and visceral sensations, vasomotor activity, hunger, thirst, and 'air hunger'. In humans, a meta-representation of the primary interoceptive activity is engendered in the right anterior insula, which seems to provide the basis for the subjective image of the material self as a feeling (sentient) entity, that is, emotional awareness. PMID:12965300

  13. The Effects Of An Exercise Physiology Program on Physical Fitness Variables, Body Satisfaction, and Physiology Knowledge.

    ERIC Educational Resources Information Center

    Perry, Arlette C.; Rosenblatt, Evelyn S.; Kempner, Lani; Feldman, Brandon B.; Paolercio, Maria A.; Van Bemden, Angie L.

    2002-01-01

    Examined the effects of an exercise physiology program on high school students' physical fitness, body satisfaction, and physiology knowledge. Intervention students received exercise physiology theory and active aerobic and resistance exercise within their biology course. Data from student surveys and measurements indicated that the integrated…

  14. Magnetic human body communication.

    PubMed

    Park, Jiwoong; Mercier, Patrick P

    2015-08-01

    This paper presents a new human body communication (HBC) technique that employs magnetic resonance for data transfer in wireless body-area networks (BANs). Unlike electric field HBC (eHBC) links, which do not necessarily travel well through many biological tissues, the proposed magnetic HBC (mHBC) link easily travels through tissue, offering significantly reduced path loss and, as a result, reduced transceiver power consumption. In this paper the proposed mHBC concept is validated via finite element method simulations and measurements. It is demonstrated that path loss across the body under various postures varies from 10-20 dB, which is significantly lower than alternative BAN techniques. PMID:26736639

  15. Virtual physiological human: training challenges.

    PubMed

    Lawford, Patricia V; Narracott, Andrew V; McCormack, Keith; Bisbal, Jesus; Martin, Carlos; Bijnens, Bart; Brook, Bindi; Zachariou, Margarita; Freixa, Jordi Villà I; Kohl, Peter; Fletcher, Katherine; Diaz-Zuccarini, Vanessa

    2010-06-28

    The virtual physiological human (VPH) initiative encompasses a wide range of activities, including structural and functional imaging, data mining, knowledge discovery tool and database development, biomedical modelling, simulation and visualization. The VPH community is developing from a multitude of relatively focused, but disparate, research endeavours into an integrated effort to bring together, develop and translate emerging technologies for application, from academia to industry and medicine. This process initially builds on the evolution of multi-disciplinary interactions and abilities, but addressing the challenges associated with the implementation of the VPH will require, in the very near future, a translation of quantitative changes into a new quality of highly trained multi-disciplinary personnel. Current strategies for undergraduate and on-the-job training may soon prove insufficient for this. The European Commission seventh framework VPH network of excellence is exploring this emerging need, and is developing a framework of novel training initiatives to address the predicted shortfall in suitably skilled VPH-aware professionals. This paper reports first steps in the implementation of a coherent VPH training portfolio. PMID:20478909

  16. Design Projects in Human Anatomy & Physiology

    ERIC Educational Resources Information Center

    Polizzotto, Kristin; Ortiz, Mary T.

    2008-01-01

    Very often, some type of writing assignment is required in college entry-level Human Anatomy and Physiology courses. This assignment can be anything from an essay to a research paper on the literature, focusing on a faculty-approved topic of interest to the student. As educators who teach Human Anatomy and Physiology at an urban community college,…

  17. Gravitational Effects on Human Physiology.

    PubMed

    Atomi, Yoriko

    2015-01-01

    Physical working capacity decreases with age and also in microgravity. Regardless of age, increased physical activity can always improve the physical adaptability of the body, although the mechanisms of this adaptability are unknown. Physical exercise produces various mechanical stimuli in the body, and these stimuli may be essential for cell survival in organisms. The cytoskeleton plays an important role in maintaining cell shape and tension development, and in various molecular and/or cellular organelles involved in cellular trafficking. Both intra and extracellular stimuli send signals through the cytoskeleton to the nucleus and modulate gene expression via an intrinsic property, namely the "dynamic instability" of cytoskeletal proteins. αB-crystallin is an important chaperone for cytoskeletal proteins in muscle cells. Decreases in the levels of αB-crystallin are specifically associated with a marked decrease in muscle mass (atrophy) in a rat hindlimb suspension model that mimics muscle and bone atrophy that occurs in space and increases with passive stretch. Moreover, immunofluorescence data show complete co-localization of αB-crystallin and the tubulin/microtubule system in myoblast cells. This association was further confirmed in biochemical experiments carried out in vitro showing that αB-crystallin acts as a chaperone for heat-denatured tubulin and prevents microtubule disassembly induced by calcium. Physical activity induces the constitutive expression of αB-crystallin, which helps to maintain the homeostasis of cytoskeleton dynamics in response to gravitational forces. This relationship between chaperone expression levels and regulation of cytoskeletal dynamics observed in slow anti-gravitational muscles as well as in mammalian striated muscles, such as those in the heart, diaphragm and tongue, may have been especially essential for human evolution in particular. Elucidation of the intrinsic properties of the tubulin/microtubule and chaperone

  18. Molecular physiology of weight regulation in mice and humans

    PubMed Central

    Leibel, RL

    2009-01-01

    Evolutionary considerations relating to efficiency in reproduction, and survival in hostile environments, suggest that body energy stores are sensed and actively regulated, with stronger physiological and behavioral responses to loss than gain of stored energy. Many physiological studies support this inference, and suggest that a critical axis runs between body fat and the hypothalamus. The molecular cloning of leptin and its receptor—projects based explicitly on the search for elements in this axis—confirmed the existence of this axis and provided important tools with which to understand its molecular physiology. Demonstration of the importance of this soma-brain reciprocal connection in body weight regulation in humans has been pursued using both classical genetic approaches and studies of physiological responses to experimental weight perturbation. This paper reviews the history of the rationale and methodology of the cloning of leptin (Lep) and the leptin receptor (Lepr), and describes some of the clinical investigation characterizing this axis. PMID:19136999

  19. A dynamic model of human physiology

    NASA Astrophysics Data System (ADS)

    Green, Melissa; Kaplan, Carolyn; Oran, Elaine; Boris, Jay

    2010-11-01

    To study the systems-level transport in the human body, we develop the Computational Man (CMAN): a set of one-dimensional unsteady elastic flow simulations created to model a variety of coupled physiological systems including the circulatory, respiratory, excretory, and lymphatic systems. The model systems are collapsed from three spatial dimensions and time to one spatial dimension and time by assuming axisymmetric vessel geometry and a parabolic velocity profile across the cylindrical vessels. To model the actions of a beating heart or expanding lungs, the flow is driven by user-defined changes to the equilibrium areas of the elastic vessels. The equations are then iteratively solved for pressure, area, and average velocity. The model is augmented with valves and contractions to resemble the biological structure of the different systems. CMAN will be used to track material transport throughout the human body for diagnostic and predictive purposes. Parameters will be adjustable to match those of individual patients. Validation of CMAN has used both higher-dimensional simulations of similar geometries and benchmark measurement from medical literature.

  20. Human Physiology and the Environment in Health and Disease: Readings from Scientific American.

    ERIC Educational Resources Information Center

    1976

    This anthology of articles is designed to supplement standard texts for courses in human physiology, environmental physiology, anatomy and physiology, pathobiology, general biology, and environmental medicine. It focuses on the influences of the external environment on the body, the physiological responses to environmental challenges, and the ways…

  1. Human basal body basics.

    PubMed

    Vertii, Anastassiia; Hung, Hui-Fang; Hehnly, Heidi; Doxsey, Stephen

    2016-01-01

    In human cells, the basal body (BB) core comprises a ninefold microtubule-triplet cylindrical structure. Distal and subdistal appendages are located at the distal end of BB, where they play indispensable roles in cilium formation and function. Most cells that arrest in the G0 stage of the cell cycle initiate BB docking at the plasma membrane followed by BB-mediated growth of a solitary primary cilium, a structure required for sensing the extracellular environment and cell signaling. In addition to the primary cilium, motile cilia are present in specialized cells, such as sperm and airway epithelium. Mutations that affect BB function result in cilia dysfunction. This can generate syndromic disorders, collectively called ciliopathies, for which there are no effective treatments. In this review, we focus on the features and functions of BBs and centrosomes in Homo sapiens. PMID:26981235

  2. HUMAN--A Comprehensive Physiological Model.

    ERIC Educational Resources Information Center

    Coleman, Thomas G.; Randall, James E.

    1983-01-01

    Describes computer program (HUMAN) used to simulate physiological experiments on patient pathology. Program (available from authors, including versions for microcomputers) consists of dynamic interactions of over 150 physiological variables and integrating approximations of cardiovascular, renal, lung, temperature regulation, and some hormone…

  3. Human Physiological Responses to Acute and Chronic Cold Exposure

    NASA Technical Reports Server (NTRS)

    Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

    2001-01-01

    When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

  4. Human body temperature - Its measurement and regulation

    SciTech Connect

    Houdas, Y.; Ring, E.F.J.

    1982-01-01

    The terminology used in thermal physiology is examined, and principles of heat transfer are discussed, taking into account heat quantity, heat flux, temperature, pressure, quantities used in physiology, a number of common definitions, the equivalence between different forms of energy, the release of potential energy in living tissues, heat transfer without change of state, and heat transfer with change of state. Temperature and humidity measurement are considered along with man and his environment, the temperature distribution in the systems and tracts of the human body, physiological changes affecting the temperature distribution, problems of temperature regulation, questions of heat loss and conservation, acclimatization to heat and cold, and disorders of thermoregulation. Attention is given to possible thermal imaging applications, causes of temperature irregularities in the head and neck, common causes of increased temperatures of upper limbs, and thermography in disease. 193 references.

  5. Impact of human emotions on physiological characteristics

    NASA Astrophysics Data System (ADS)

    Partila, P.; Voznak, M.; Peterek, T.; Penhaker, M.; Novak, V.; Tovarek, J.; Mehic, Miralem; Vojtech, L.

    2014-05-01

    Emotional states of humans and their impact on physiological and neurological characteristics are discussed in this paper. This problem is the goal of many teams who have dealt with this topic. Nowadays, it is necessary to increase the accuracy of methods for obtaining information about correlations between emotional state and physiological changes. To be able to record these changes, we focused on two majority emotional states. Studied subjects were psychologically stimulated to neutral - calm and then to the stress state. Electrocardiography, Electroencephalography and blood pressure represented neurological and physiological samples that were collected during patient's stimulated conditions. Speech activity was recording during the patient was reading selected text. Feature extraction was calculated by speech processing operations. Classifier based on Gaussian Mixture Model was trained and tested using Mel-Frequency Cepstral Coefficients extracted from the patient's speech. All measurements were performed in a chamber with electromagnetic compatibility. The article discusses a method for determining the influence of stress emotional state on the human and his physiological and neurological changes.

  6. A long term model of circulation. [human body

    NASA Technical Reports Server (NTRS)

    White, R. J.

    1974-01-01

    A quantitative approach to modeling human physiological function, with a view toward ultimate application to long duration space flight experiments, was undertaken. Data was obtained on the effect of weightlessness on certain aspects of human physiological function during 1-3 month periods. Modifications in the Guyton model are reviewed. Design considerations for bilateral interface models are discussed. Construction of a functioning whole body model was studied, as well as the testing of the model versus available data.

  7. Impact of nesting material on mouse body temperature and physiology.

    PubMed

    Gaskill, Brianna N; Gordon, Christopher J; Pajor, Edmond A; Lucas, Jeffrey R; Davis, Jerry K; Garner, Joseph P

    2013-02-17

    In laboratories, mice are housed at 20-24 °C, which is below their lower critical temperature (≈30 °C). Thus, mice are potentially cold stressed, which can alter metabolism, immune function, and reproduction. These physiological changes reflect impaired wellbeing, and affect scientific outcomes. We hypothesized that nesting material would allow mice to alleviate cold stress by controlling their thermal microenvironment, thus insulating them, reducing heat loss and thermogenic processes. Naïve C57BL/6, CD-1, and BALB/c mice (24 male and 24 female/strain in groups of 3) were housed in standard cages at 20 °C either with or without 8 g nesting material for 4 weeks. Core body temperature was followed using intraperitoneal radio telemetry. The thermal properties of the nests were assessed using a thermal imaging camera, and related to nest quality. Higher scoring nests were negatively correlated with the mean radiated temperature and were thus more insulating. No effects of nesting material on body temperature were found. CD-1 mice with nesting material had higher end body weights than controls. No effect was seen in the other two strains. Mice with the telemetry implant had larger spleens than controls, possibly indicating an immune response to the implant or low level infection from the surgery. BALB/c mice express less mRNA for the UCP1 protein than mice without nesting material. This indicates that BALB/c's with nesting material do not utilize their brown fat to create heat as readily as controls. Nests can alleviate thermal discomfort by decreasing the amount of radiated heat and reduce the need for non-shivering thermogenesis. However, different strains appear to use different behavioral (through different primary modes of behavioral thermoregulation) and physiological strategies (utilizing thermogenesis to different degrees) to maintain a constant body temperature under cool standard laboratory ambient temperatures. PMID:23313562

  8. Scaling the physiological effects of exposure to radiofrequency electromagnetic radiation: consequences of body size

    SciTech Connect

    Gordon, C.J.; Ferguson, J.H.

    1984-01-01

    The authors have demonstrated that a comparative analysis of the physiological effects of exposure of laboratory mammals to radiofrequency electromagnetic radiation (RFR) may be useful in predicting exposure thresholds for humans if the effect is assumed to be due only to heating of tissue. The threshold specific absorption rate (SAR) necessary to affect a thermoregulatory parameter shows an inverse and linear relationship to body mass. The inverse relationship between threshold SAR and body mass is attributed to a surface area: body mass relationship. In comparison to small mammals, relatively large mammals have a reduced capacity to dissipate an internal heat load passively, and are therefore physiologically more sensitive to RFR exposure. The threshold for a thermoregulatory response depends on the type of response measured, species, ambient temperature, etc.

  9. Variability in human body size

    NASA Technical Reports Server (NTRS)

    Annis, J. F.

    1978-01-01

    The range of variability found among homogeneous groups is described and illustrated. Those trends that show significantly marked differences between sexes and among a number of racial/ethnic groups are also presented. Causes of human-body size variability discussed include genetic endowment, aging, nutrition, protective garments, and occupation. The information is presented to aid design engineers of space flight hardware and equipment.

  10. [Wireless human body communication technology].

    PubMed

    Sun, Lei; Zhang, Xiaojuan

    2014-12-01

    The Wireless Body Area Network (WBAN) is a key part of the wearable monitoring technologies, which has many communication technologies to choose from, like Bluetooth, ZigBee, Ultra Wideband, and Wireless Human Body Communication (WHBC). As for the WHBC developed in recent years, it is worthy to be further studied. The WHBC has a strong momentum of growth and a natural advantage in the formation of WBAN. In this paper, we first briefly describe the technical background of WHBC, then introduce theoretical model of human-channel communication and digital transmission machine based on human channel. And finally we analyze various of the interference of the WHBC and show the AFH (Adaptive Frequency Hopping) technology which can effectively deal with the interference. PMID:25868265

  11. Body composition and physiological characteristics of law enforcement officers.

    PubMed Central

    Spitler, D L; Jones, G; Hawkins, J; Dudka, L

    1987-01-01

    The physical work capacity, body composition, and physiological characteristics of 12 law enforcement officers (9 males, 3 females) were measured. Subjects included a representative sample from the occupational categories of detective, staff, investigative and patrol officer. Mean maximal oxygen uptake of the men was 42.1 +/- 8.9 ml.kg-1min-1 with mean values of 41.5 +/- 8.7 ml.kg-1min-1 for the women. Measurement of body composition indicated an average of 24.4 +/- 7.1% body fat for the men and 30.9 +/- 1.2% for the women. Muscular power, strength, and endurance as measured by isolated limb flexion-extension movement and fitness test performance was considered average with no excessive bilateral differences. The results of this study were compared with other investigations of law enforcement officers of similar age groups. The officers displayed average or above health and physical fitness scores for their age classification and were able to complete all police task-oriented tests. PMID:3435817

  12. Leptin in human physiology and pathophysiology

    PubMed Central

    Magkos, Faidon; Brinkoetter, Mary; Sienkiewicz, Elizabeth; Dardeno, Tina A.; Kim, Sang-Yong; Hamnvik, Ole-Petter R.; Koniaris, Anastasia

    2011-01-01

    Leptin, discovered through positional cloning 15 years ago, is an adipocyte-secreted hormone with pleiotropic effects in the physiology and pathophysiology of energy homeostasis, endocrinology, and metabolism. Studies in vitro and in animal models highlight the potential for leptin to regulate a number of physiological functions. Available evidence from human studies indicates that leptin has a mainly permissive role, with leptin administration being effective in states of leptin deficiency, less effective in states of leptin adequacy, and largely ineffective in states of leptin excess. Results from interventional studies in humans demonstrate that leptin administration in subjects with congenital complete leptin deficiency or subjects with partial leptin deficiency (subjects with lipoatrophy, congenital or related to HIV infection, and women with hypothalamic amenorrhea) reverses the energy homeostasis and neuroendocrine and metabolic abnormalities associated with these conditions. More specifically, in women with hypothalamic amenorrhea, leptin helps restore abnormalities in hypothalamic-pituitary-peripheral axes including the gonadal, thyroid, growth hormone, and to a lesser extent adrenal axes. Furthermore, leptin results in resumption of menses in the majority of these subjects and, in the long term, may increase bone mineral content and density, especially at the lumbar spine. In patients with congenital or HIV-related lipoatrophy, leptin treatment is also associated with improvements in insulin sensitivity and lipid profile, concomitant with reduced visceral and ectopic fat deposition. In contrast, leptin's effects are largely absent in the obese hyperleptinemic state, probably due to leptin resistance or tolerance. Hence, another emerging area of research pertains to the discovery and/or usefulness of leptin sensitizers. Results from ongoing studies are expected to further increase our understanding of the role of leptin and the potential clinical

  13. The Virtual Physiological Human: Ten Years After.

    PubMed

    Viceconti, Marco; Hunter, Peter

    2016-07-11

    Biomedical research and clinical practice are struggling to cope with the growing complexity that the progress of health care involves. The most challenging diseases, those with the largest socioeconomic impact (cardiovascular conditions; musculoskeletal conditions; cancer; metabolic, immunity, and neurodegenerative conditions), are all characterized by a complex genotype-phenotype interaction and by a "systemic" nature that poses a challenge to the traditional reductionist approach. In 2005 a small group of researchers discussed how the vision of computational physiology promoted by the Physiome Project could be translated into clinical practice and formally proposed the term Virtual Physiological Human. Our knowledge about these diseases is fragmentary, as it is associated with molecular and cellular processes on the one hand and with tissue and organ phenotype changes (related to clinical symptoms of disease conditions) on the other. The problem could be solved if we could capture all these fragments of knowledge into predictive models and then compose them into hypermodels that help us tame the complexity that such systemic behavior involves. In 2005 this was simply not possible-the necessary methods and technologies were not available. Now, 10 years later, it seems the right time to reflect on the original vision, the results achieved so far, and what remains to be done. PMID:27420570

  14. ATHENA, the Desktop Human "Body"

    SciTech Connect

    Iyer, Rashi; Harris, Jennifer

    2014-09-29

    Creating surrogate human organs, coupled with insights from highly sensitive mass spectrometry technologies, a new project is on the brink of revolutionizing the way we screen new drugs and toxic agents. ATHENA, the Advanced Tissue-engineered Human Ectypal Network Analyzer project team, is developing four human organ constructs - liver, heart, lung and kidney - that are based on a significantly miniaturized platform. Each organ component will be about the size of a smartphone screen, and the whole ATHENA "body" of interconnected organs would fit neatly on a desk. "By developing this 'homo minutus,' we are stepping beyond the need for animal or Petri dish testing: There are huge benefits in developing drug and toxicity analysis systems that can mimic the response of actual human organs," said Rashi Iyer, a senior scientist at Los Alamos National Laboratory, the lead laboratory on the five-year, $19 million multi-institutional effort. The project is supported by the Defense Threat Reduction Agency (DTRA). Some 40 percent of pharmaceuticals fail their clinical trials, Iyer noted, and there are thousands of chemicals whose effects on humans are simply unknown. Providing a realistic, cost-effective and rapid screening system such as ATHENA with high-throughput capabilities could provide major benefits to the medical field, screening more accurately and offering a greater chance of clinical trial success.

  15. ATHENA, the Desktop Human "Body"

    ScienceCinema

    Iyer, Rashi; Harris, Jennifer

    2015-01-05

    Creating surrogate human organs, coupled with insights from highly sensitive mass spectrometry technologies, a new project is on the brink of revolutionizing the way we screen new drugs and toxic agents. ATHENA, the Advanced Tissue-engineered Human Ectypal Network Analyzer project team, is developing four human organ constructs - liver, heart, lung and kidney - that are based on a significantly miniaturized platform. Each organ component will be about the size of a smartphone screen, and the whole ATHENA "body" of interconnected organs would fit neatly on a desk. "By developing this 'homo minutus,' we are stepping beyond the need for animal or Petri dish testing: There are huge benefits in developing drug and toxicity analysis systems that can mimic the response of actual human organs," said Rashi Iyer, a senior scientist at Los Alamos National Laboratory, the lead laboratory on the five-year, $19 million multi-institutional effort. The project is supported by the Defense Threat Reduction Agency (DTRA). Some 40 percent of pharmaceuticals fail their clinical trials, Iyer noted, and there are thousands of chemicals whose effects on humans are simply unknown. Providing a realistic, cost-effective and rapid screening system such as ATHENA with high-throughput capabilities could provide major benefits to the medical field, screening more accurately and offering a greater chance of clinical trial success.

  16. Physiological basis for human autonomic rhythms

    NASA Technical Reports Server (NTRS)

    Eckberg, D. L.

    2000-01-01

    Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a

  17. Physiological basis for human autonomic rhythms.

    PubMed

    Eckberg, D L

    2000-07-01

    Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a

  18. Low-field MRI for studies of human pulmonary physiology and traumatic brain injury

    NASA Astrophysics Data System (ADS)

    Wilson, Alyssa; Devience, Stephen; Rosen, Matthew; Walsworth, Ronald

    2011-05-01

    We describe recent progress on the development of an open-access low-magnetic-field MRI system for studies of human pulmonary physiology and traumatic brain injury. Low-field MRI benefits from reduced magnetic susceptibility effects and can provide high-resolution images of the human body when used with hyperpolarized media such as 3He and 129Xe.

  19. Deformable human body model development

    SciTech Connect

    Wray, W.O.; Aida, T.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). A Deformable Human Body Model (DHBM) capable of simulating a wide variety of deformation interactions between man and his environment has been developed. The model was intended to have applications in automobile safety analysis, soldier survivability studies and assistive technology development for the disabled. To date, we have demonstrated the utility of the DHBM in automobile safety analysis and are currently engaged in discussions with the U.S. military involving two additional applications. More specifically, the DHBM has been incorporated into a Virtual Safety Lab (VSL) for automobile design under contract to General Motors Corporation. Furthermore, we have won $1.8M in funding from the U.S. Army Medical Research and Material Command for development of a noninvasive intracranial pressure measurement system. The proposed research makes use of the detailed head model that is a component of the DHBM; the project duration is three years. In addition, we have been contacted by the Air Force Armstrong Aerospace Medical Research Laboratory concerning possible use of the DHBM in analyzing the loads and injury potential to pilots upon ejection from military aircraft. Current discussions with Armstrong involve possible LANL participation in a comparison between DHBM and the Air Force Articulated Total Body (ATB) model that is the current military standard.

  20. Association Between Body Weight Growth and Selected Physiological Parameters in Male Japanese Quail (Coturnrix japonica)

    PubMed Central

    Vatsalya, Vatsalya; Arora, Kashmiri L.

    2014-01-01

    Japanese quail is very popular research animal model. Its continued characterization for various norms is highly desirable for obtaining accurate and reliable results. This study was designed to assess various physiological parameters which are associated with body growth and development. Among various physiological parameters, blood constituents and hormones are commonly used as diagnostic tools in both physiological and pathological evaluations of humans and animals. Japanese quail hatchlings were housed in the temperature controlled brooders up to 3 weeks of age and then shifted to hanging cages in air conditioned room at ~74 F under 14L:10D lighting system and free access to feed and fresh water. Starting d8, a group of birds of uniform size and weight were selected randomly and euthanized at 4-day intervals up to d52 of age. The birds were weighed and blood sampled from the brachial vein for measuring Blood Glucose (BGL), Total Plasma Proteins (PP) and Packed Cell Volume (PCV). It was found that starting d36 all the three physiological parameters altered with approaching sexual maturity (d48–52): BGL decreased (252 vrs. 182 mg/dl, p<0.05), PCV% increased (43.6 vrs. 49.6%, p<0.05) and PP also increased (2.7 vrs. 3.2 gm/dl, p>0.05). Accordingly, BGL, PCV and PP values demonstrated significant potential to predict approaching sexual maturity in male Japanese quail. PMID:25285100

  1. Introduction to the Human Body

    MedlinePlus

    ... Central Nervous System Peripheral Nervous System Review Quiz Endocrine System Characteristics of Hormones Endocrine Glands & Their Hormones Pituitary & ... Thyroid & Parathyroid Glands Adrenal Gland Pancreas Gonads Other Endocrine Glands ... Cardiovascular System Heart Structure of the Heart Physiology of the ...

  2. Arterial load and ventricular-arterial coupling: physiologic relations with body size and effect of obesity.

    PubMed

    Chirinos, Julio A; Rietzschel, Ernst R; De Buyzere, Marc L; De Bacquer, Dirk; Gillebert, Thierry C; Gupta, Amit K; Segers, Patrick

    2009-09-01

    Accurate quantification of arterial function is crucial to distinguishing disease states from normal variants. However, there are little data regarding methods to scale arterial load to body size in humans. We studied 2365 adults aged 35 to 55 years free of overt cardiovascular disease. We assessed arterial hemodynamics and ventricular-vascular coupling with carotid tonometry and Doppler echocardiography. To define normal (physiological) relationships between hemodynamic indices and body size, we used nonlinear regression to analyze a selected reference subsample (n=612) with normal weight (body mass index 18 to 25 kg/m(2)), waist circumference, and metabolic parameters. Most arterial hemodynamic indices demonstrated important relationships with body size, which were frequently allometric (nonlinear). Allometric indexation using appropriate powers (but not ratiometric indexation) effectively eliminated the relationships between indices of arterial load and body size in normal subjects. In the entire sample (n=2365), the adverse effects of obesity on arterial load and end-systolic ventricular stiffening were clearly demonstrated only after appropriate indexation to account for the expected normal relationship to body size. After adjustment for age and sex, a progressive increase in indexed systemic vascular resistance, effective arterial and ventricular end-systolic elastance, and a decrease in total arterial compliance were seen from normal weight to obesity (P<0.0001). Arterial load relates to body size in an allometric fashion, calling for scaling with the use of appropriate powers. Obesity exerts adverse effects on arterial load and ventricular stiffening that go beyond the normal relationship with body size. Allometric normalization should allow more accurate quantification of arterial load in future studies. PMID:19581507

  3. A Method of Ground Simulation of Physiological Effects of Hypogravity on Humans.

    PubMed

    Baranov, M V; Katuntsev, V P; Shpakov, A V; Baranov, V M

    2016-01-01

    A novel method of ground simulation in humans of physiological effects induced by the stay on the surface of celestial bodies with hypogravity was developed and successfully tested. This method is based on the change of gravity force angle, which decreases the gravitational component of the blood hydrostatic pressure characteristic of human vertical posture on the Earth and the load-weight onto the locomotor apparatus to the lower values expected at celestial bodies with hypogravity. The methodological requirements for ground simulation of the physiological effects of lunar gravity on human body are specified and substantiated by theoretical calculations. The experimental study revealed redistribution of liquid media in the human organism, functional changes in the cardiorespiratory system, and a decrease in the load-weight applied to the locomotor apparatus. PMID:26742752

  4. Inclusion bodies in loggerhead erythrocytes are associated with unstable hemoglobin and resemble human Heinz bodies.

    PubMed

    Basile, Filomena; Di Santi, Annalisa; Caldora, Mercedes; Ferretti, Luigi; Bentivegna, Flegra; Pica, Alessandra

    2011-08-01

    The aim of this study was to clarify the role of the erythrocyte inclusions found during the hematological screening of loggerhead population of the Mediterranean Sea. We studied the erythrocyte inclusions in blood specimens collected from six juvenile and nine adult specimens of the loggerhead turtle, Caretta caretta, from the Adriatic and Tyrrhenian Seas. Our study indicates that the percentage of mature erythrocytes containing inclusions ranged from 3 to 82%. Each erythrocyte contained only one round inclusion body. Inclusion bodies stained with May Grünwald-Giemsa show that their cytochemical and ultrastructure characteristics are identical to those of human Heinz bodies. Because Heinz bodies originate from the precipitation of unstable hemoglobin (Hb) and cause globular osmotic resistance to increase, we analyzed loggerhead Hb using electrophoresis and high-performance liquid chromatography to detect and quantitate Hb fractions. We also tested the resistance of Hb to alkaline pH, heat, isopropanol denaturation, and globular osmosis. Our hemogram results excluded the occurrence of any infection, which could be associated with an inclusion body, in all the specimens. Negative Feulgen staining indicated that the inclusion bodies are not derived from DNA fragmentation. We hypothesize that amino acid substitutions could explain why loggerhead Hb precipitates under normal physiologic conditions, forming Heinz bodies. The identification of inclusion bodies in loggerhead erythrocytes allow us to better understand the haematological characteristics and the physiology of these ancient reptiles, thus aiding efforts to conserve such an endangered species. PMID:21538919

  5. An Investigative Laboratory Course in Human Physiology Using Computer Technology and Collaborative Writing

    ERIC Educational Resources Information Center

    FitzPatrick, Kathleen A.

    2004-01-01

    Active investigative student-directed experiences in laboratory science are being encouraged by national science organizations. A growing body of evidence from classroom assessment supports their effectiveness. This study describes four years of implementation and assessment of an investigative laboratory course in human physiology for 65…

  6. Modeling Forces on the Human Body.

    ERIC Educational Resources Information Center

    Pagonis, Vasilis; Drake, Russel; Morgan, Michael; Peters, Todd; Riddle, Chris; Rollins, Karen

    1999-01-01

    Presents five models of the human body as a mechanical system which can be used in introductory physics courses: human arms as levers, humans falling from small heights, a model of the human back, collisions during football, and the rotating gymnast. Gives ideas for discussions and activities, including Interactive Physics (TM) simulations. (WRM)

  7. Geomagnetic Indices Variations And Human Physiology

    NASA Astrophysics Data System (ADS)

    Dimitrova, S.

    2007-12-01

    A group of 86 volunteers was examined on each working day in autumn 2001 and in spring 2002. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were registered. Pulse pressure (PP) was calculated. Data about subjective psycho-physiological complaints (SPPC) were also gathered. Altogether 2799 recordings were obtained. ANOVA was employed to check the significance of influence of daily amplitude of H-component of local geomagnetic field, daily planetary Ap-index and hourly planetary Dst-index on the physiological parameters examined. Post hoc analysis was performed to elicit the significance of differences in the factors levels. Average values of SBP, DBP, PP and SPPC of the group were found to increase statistically significantly and biologically considerably with the increase of geomagnetic indices.

  8. Physiological responses during whole body suspension of adult rats

    NASA Technical Reports Server (NTRS)

    Steffen, J. M.; Fell, R. D.; Musacchia, X. J.

    1987-01-01

    The objective of this study was to characterize responses of adult rats to one and two weeks of whole body suspension. Body weights and food and water intakes were initially reduced during suspension, but, while intake of food and water returned to presuspension levels, body weight remained depressed. Diuresis was evident, but only during week two. Hindlimb muscle responses were differential, with the soleus exhibiting the greatest atrophy and the EDL a relative hypertrophy. These findings suggest that adult rats respond qualitatively in a manner similar to juveniles during suspension.

  9. Human Adaptation to Space: Space Physiology and Countermeasures

    NASA Technical Reports Server (NTRS)

    Fogarty, Jennifer

    2009-01-01

    This viewgraph presentation reviews human physiological responses to spaceflight, and the countermeasures taken to prevent adverse effects of manned space flight. The topics include: 1) Human Spaceflight Experience; 2) Human Response to Spaceflight; 3) ISS Expeditions 1-16; 4) Countermeasure; and 5) Biomedical Data;

  10. Physiological Health Challenges for Human Missions to Mars

    NASA Technical Reports Server (NTRS)

    Norsk, Peter

    2015-01-01

    During the next decades, manned space missions are expected to be aiming at the Lagrange points, near Earth asteroids, and Mars flyby and/or landing. The question is therefore: Are we ready to go? To answer this with a yes, we are currently using the International Space Station to develop an integrated human physiological countermeasure suite. The integrated countermeasure suite will most likely encounter: 1) Exercise devices for aerobic, dynamic and resistive exercise training; 2) sensory-motor computer training programs and anti-motion sickness medication for preparing EVAs and G-transitions; 3) lower limb bracelets for preventing and/or treating the VIIP (vision impairment and intracranial pressure) syndrome; 4) nutritional components for maintenance of bone, muscle, the cardiovascular system and preventing oxidative stress and damage and immune deficiencies (e. g. omega-3 fatty acids, PRO/K, anti-oxidants and less salt and iron); 5) bisphosphonates for preventing bone degradation.; 6) lower body compression garment and oral salt and fluid loading for landing on a planetary surface to combat orthostatic intolerance; 7) laboratory analysis equipment for individualized monitoring of biomarkers in blood, urine and saliva for estimation of health status in; 8) advanced ultrasound techniques for monitoring bone and cardiovascular health; and 9) computer modeling programs for individual health status assessments of efficiency and subsequent adjustments of countermeasures. In particular for future missions into deep space, we are concerned with the synergistic effects of weightlessness, radiation, operational constraints and other spaceflight environmental factors. Therefore, increased collaboration between physiological, behavioral, radiation and space vehicle design disciplines are strongly warranted. Another venue we are exploring in NASA's Human Research Program is the usefulness of artificial gravity for mitigating the health risks of long duration weightlessness.

  11. Anatomy and Physiology. Module Set II: Major Body Systems. Teacher Edition [and] Student Edition. Surgical Technology.

    ERIC Educational Resources Information Center

    Hilley, Robert

    This document, which is the second part of a two-part set of modules on anatomy and physiology for future surgical technicians, contains the teacher and student editions of an introduction to anatomy and physiology that consists of modules on the following body systems: integumentary system; skeletal system; muscular system; nervous system;…

  12. Thermoregulatory responses in exercising rats: methodological aspects and relevance to human physiology

    PubMed Central

    Wanner, Samuel Penna; Prímola-Gomes, Thales Nicolau; Pires, Washington; Guimarães, Juliana Bohnen; Hudson, Alexandre Sérvulo Ribeiro; Kunstetter, Ana Cançado; Fonseca, Cletiana Gonçalves; Drummond, Lucas Rios; Damasceno, William Coutinho; Teixeira-Coelho, Francisco

    2015-01-01

    Rats are used worldwide in experiments that aim to investigate the physiological responses induced by a physical exercise session. Changes in body temperature regulation, which may affect both the performance and the health of exercising rats, are evident among these physiological responses. Despite the universal use of rats in biomedical research involving exercise, investigators often overlook important methodological issues that hamper the accurate measurement of clear thermoregulatory responses. Moreover, much debate exists regarding whether the outcome of rat experiments can be extrapolated to human physiology, including thermal physiology. Herein, we described the impact of different exercise intensities, durations and protocols and environmental conditions on running-induced thermoregulatory changes. We focused on treadmill running because this type of exercise allows for precise control of the exercise intensity and the measurement of autonomic thermoeffectors associated with heat production and loss. Some methodological issues regarding rat experiments, such as the sites for body temperature measurements and the time of day at which experiments are performed, were also discussed. In addition, we analyzed the influence of a high body surface area-to-mass ratio and limited evaporative cooling on the exercise-induced thermoregulatory responses of running rats and then compared these responses in rats to those observed in humans. Collectively, the data presented in this review represent a reference source for investigators interested in studying exercise thermoregulation in rats. In addition, the present data indicate that the thermoregulatory responses of exercising rats can be extrapolated, with some important limitations, to human thermal physiology. PMID:27227066

  13. Thermoregulatory responses in exercising rats: methodological aspects and relevance to human physiology.

    PubMed

    Wanner, Samuel Penna; Prímola-Gomes, Thales Nicolau; Pires, Washington; Guimarães, Juliana Bohnen; Hudson, Alexandre Sérvulo Ribeiro; Kunstetter, Ana Cançado; Fonseca, Cletiana Gonçalves; Drummond, Lucas Rios; Damasceno, William Coutinho; Teixeira-Coelho, Francisco

    2015-01-01

    Rats are used worldwide in experiments that aim to investigate the physiological responses induced by a physical exercise session. Changes in body temperature regulation, which may affect both the performance and the health of exercising rats, are evident among these physiological responses. Despite the universal use of rats in biomedical research involving exercise, investigators often overlook important methodological issues that hamper the accurate measurement of clear thermoregulatory responses. Moreover, much debate exists regarding whether the outcome of rat experiments can be extrapolated to human physiology, including thermal physiology. Herein, we described the impact of different exercise intensities, durations and protocols and environmental conditions on running-induced thermoregulatory changes. We focused on treadmill running because this type of exercise allows for precise control of the exercise intensity and the measurement of autonomic thermoeffectors associated with heat production and loss. Some methodological issues regarding rat experiments, such as the sites for body temperature measurements and the time of day at which experiments are performed, were also discussed. In addition, we analyzed the influence of a high body surface area-to-mass ratio and limited evaporative cooling on the exercise-induced thermoregulatory responses of running rats and then compared these responses in rats to those observed in humans. Collectively, the data presented in this review represent a reference source for investigators interested in studying exercise thermoregulation in rats. In addition, the present data indicate that the thermoregulatory responses of exercising rats can be extrapolated, with some important limitations, to human thermal physiology. PMID:27227066

  14. Biodynamics of deformable human body motion

    NASA Technical Reports Server (NTRS)

    Strauss, A. M.; Huston, R. L.

    1976-01-01

    The objective is to construct a framework wherein the various models of human biomaterials fit in order to describe the biodynamic response of the human body. The behavior of the human body in various situations, from low frequency, low amplitude vibrations to impact loadings in automobile and aircraft crashes, is very complicated with respect to all aspects of the problem: materials, geometry and dynamics. The materials problem is the primary concern, but the materials problem is intimately connected with geometry and dynamics.

  15. Telescience testbed in human space physiology

    NASA Astrophysics Data System (ADS)

    Watanabe, Satoru; Seo, Hisao; Iwase, Satoshi; Tanaka, Masafumi; Kaneko, Sayumi; Mano, Tadaaki; Matsui, Nobuo; Foldager, Niels; Bondepetersen, Flemming; Yamashita, Masamichi; Shoji, Takatoshi; Sudoh, Hideo

    The present telescience testbed study was conducted to evaluate the feasibility of physiological experimentation under restricted conditions such as during simulated weightlessness induced by using a water immersion facility, a reduced capacity of laboratory facilities, a delay and desynchronization of communication between investigator and operator, restrictions of different kinds of experiments practiced by only one operator following a limited time line and so on. The three day's experiments were carried out following the same protocols. The operators were changed every day, but was the same the first and the third day. The operators were both medical doctors but not all round experts in the physiological experimentation. The experimental objectives were: 1) ECG changes by changing water immersion levels, 2) blood pressure changes, 3) ultrasonic Echo-cardiographic changes, 4) laser Doppler skin blood flowmetry in a finger, 5) blood sampling to examine blood electrolytic and humoral changes. The effectiveness of the testbed experiment was assessed by evaluating the quality of the obtained data and estimating the friendliness of the operation of the telescience to investigators and operators.

  16. Human fine body hair enhances ectoparasite detection

    PubMed Central

    Dean, Isabelle; Siva-Jothy, Michael T.

    2012-01-01

    Although we are relatively naked in comparison with other primates, the human body is covered in a layer of fine hair (vellus and terminal hair) at a relatively high follicular density. There are relatively few explanations for the evolutionary maintenance of this type of human hair. Here, we experimentally test the hypothesis that human fine body hair plays a defensive function against ectoparasites (bed bugs). Our results show that fine body hair enhances the detection of ectoparasites through the combined effects of (i) increasing the parasite's search time and (ii) enhancing its detection. PMID:22171023

  17. Effect of Light on Human Circadian Physiology

    PubMed Central

    Duffy, Jeanne F.; Czeisler, Charles A.

    2009-01-01

    Synopsis The circadian system in animals and humans, being near but not exactly 24-hours in cycle length, must be reset on a daily basis in order to remain in synchrony with external environmental time. This process of entrainment is achieved in most mammals through regular exposure to light and darkness. In this chapter, we review the results of studies conducted in our laboratory and others over the past 25 years in which the effects of light on the human circadian timing system were investigated. These studies have revealed, how the timing, intensity, duration, and wavelength of light affect the human biological clock. Our most recent studies also demonstrate that there is much yet to learn about the effects of light on the human circadian timing system. PMID:20161220

  18. Physiologic Responses of Able-Bodied and Paraplegic Males to Maximal Arm Ergometry.

    ERIC Educational Resources Information Center

    Israel, Richard G.; And Others

    A study compared physiologic responses of healthy paraplegic males to those of healthy, able-bodied males during maximal arm ergometry. Fifteen able-bodied, healthy adult males and 13 healthy adult male paraplegics followed an exercise program involving heart rate, increased exercise loads, and oxygen uptake. Results from an analysis of the data…

  19. EVOKED POTENTIALS, PHYSIOLOGICAL METHODS WITH HUMAN APPLICATIONS

    EPA Science Inventory

    A number of tests and test batteries have been developed and implemented for detecting potential neurotoxicity in humans. n some cases test results may suggest specific dysfunction. hile tests in laboratory animals are often used to project the potential for adverse health effect...

  20. Human physiological responses to cold exposure: Acute responses and acclimatization to prolonged exposure.

    PubMed

    Castellani, John W; Young, Andrew J

    2016-04-01

    Cold exposure in humans causes specific acute and chronic physiological responses. This paper will review both the acute and long-term physiological responses and external factors that impact these physiological responses. Acute physiological responses to cold exposure include cutaneous vasoconstriction and shivering thermogenesis which, respectively, decrease heat loss and increase metabolic heat production. Vasoconstriction is elicited through reflex and local cooling. In combination, vasoconstriction and shivering operate to maintain thermal balance when the body is losing heat. Factors (anthropometry, sex, race, fitness, thermoregulatory fatigue) that influence the acute physiological responses to cold exposure are also reviewed. The physiological responses to chronic cold exposure, also known as cold acclimation/acclimatization, are also presented. Three primary patterns of cold acclimatization have been observed, a) habituation, b) metabolic adjustment, and c) insulative adjustment. Habituation is characterized by physiological adjustments in which the response is attenuated compared to an unacclimatized state. Metabolic acclimatization is characterized by an increased thermogenesis, whereas insulative acclimatization is characterized by enhancing the mechanisms that conserve body heat. The pattern of acclimatization is dependent on changes in skin and core temperature and the exposure duration. PMID:26924539

  1. New Window into the Human Body

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Michael Vannier, MD, a former NASA engineer, recognized the similarity between NASA's computerized image processing technology and nuclear magnetic resonance. With technical assistance from Kennedy Space Center, he developed a computer program for Mallinckrodt Institute of Radiology enabling Nuclear Magnetic Resonance (NMR) to scan body tissue for earlier diagnoses. Dr. Vannier feels that "satellite imaging" has opened a new window into the human body.

  2. Human Physiology in an Aquatic Environment.

    PubMed

    Pendergast, David R; Moon, Richard E; Krasney, John J; Held, Heather E; Zamparo, Paola

    2015-10-01

    Water covers over 70% of the earth, has varying depths and temperatures and contains much of the earth's resources. Head-out water immersion (HOWI) or submersion at various depths (diving) in water of thermoneutral (TN) temperature elicits profound cardiorespiratory, endocrine, and renal responses. The translocation of blood into the thorax and elevation of plasma volume by autotransfusion of fluid from cells to the vascular compartment lead to increased cardiac stroke volume and output and there is a hyperperfusion of some tissues. Pulmonary artery and capillary hydrostatic pressures increase causing a decline in vital capacity with the potential for pulmonary edema. Atrial stretch and increased arterial pressure cause reflex autonomic responses which result in endocrine changes that return plasma volume and arterial pressure to preimmersion levels. Plasma volume is regulated via a reflex diuresis and natriuresis. Hydrostatic pressure also leads to elastic loading of the chest, increasing work of breathing, energy cost, and thus blood flow to respiratory muscles. Decreases in water temperature in HOWI do not affect the cardiac output compared to TN; however, they influence heart rate and the distribution of muscle and fat blood flow. The reduced muscle blood flow results in a reduced maximal oxygen consumption. The properties of water determine the mechanical load and the physiological responses during exercise in water (e.g. swimming and water based activities). Increased hydrostatic pressure caused by submersion does not affect stroke volume; however, progressive bradycardia decreases cardiac output. During submersion, compressed gas must be breathed which introduces the potential for oxygen toxicity, narcosis due to nitrogen, and tissue and vascular gas bubbles during decompression and after may cause pain in joints and the nervous system. PMID:26426465

  3. Automated fudicial labeling on human body data

    NASA Astrophysics Data System (ADS)

    Lewark, Erick A.; Nurre, Joseph H.

    1998-03-01

    The Cyberware WB4 whole body scanner generates a high- resolution data set of the outer surface of the human body. The acquisition of anthropometric data from this data set is important for the development of custom sizing for the apparel industry. Software for locating anthropometric landmarks from a cloud of more than 200,000 three-dimensional data points, captured from a human subject, is presented. The first phase of identification is to locate externally placed fudicials on the human body using luminance information captured at scan time. The fudicials are then autonomously labeled and categorized according to their general position and anthropometric significance in the scan. Once registration of the landmarks is complete, body measurements may be extracted for apparel sizing.

  4. Influence of cold plastic deformation on critical pitting potential of AISI 316 L and 304 L steels in an artificial physiological solution simulating the aggressiveness of the human body.

    PubMed

    Cigada, A; Mazza, B; Pedeferri, P; Sinigaglia, D

    1977-07-01

    The effect of cold working on critical pitting potential of AISI 316 L and 304 L steels in a buffered physiological solution has been studied. In particular, the importance of deformation degree, orientation of the specimen surface to the deformation direction, and cold working temperature in lowering the critical pitting potential is shown. PMID:873942

  5. Drawing on student knowledge in human anatomy and physiology

    NASA Astrophysics Data System (ADS)

    Slominski, Tara Nicole

    Prior to instruction, students may have developed alternative conceptions about the mechanics behind human physiology. To help students re-shape these ideas into correct reasoning, the faulty characteristics reinforcing the alternative conceptions need to made explicit. This study used student-generated drawings to expose alternative conceptions Human Anatomy and Physiology students had prior to instruction on neuron physiology. Specifically, we investigated how students thought about neuron communication across a synapse (n=355) and how neuron activity can be modified (n=311). When asked to depict basic communication between two neurons, at least 80% of students demonstrated incorrect ideas about synaptic transmission. When targeting spatial and temporal summation, only eleven students (3.5%) were able to accurately depict at least one form of summation. In response to both drawing questions, student drawings revealed multiple alternative conceptions that resulted in a deeper analysis and characterization of the wide variation of student ideas.

  6. Colonic Fermentation: A Neglected Topic in Human Physiology Education

    ERIC Educational Resources Information Center

    Valeur, Jorgen; Berstad, Arnold

    2010-01-01

    Human physiology textbooks tend to limit their discussion of colonic functions to those of absorbing water and electrolytes and storing waste material. However, the colon is a highly active metabolic organ, containing an exceedingly complex society of microbes. By means of fermentation, gastrointestinal microbes break down nutrients that cannot be…

  7. Linking adult hippocampal neurogenesis with human physiology and disease.

    PubMed

    Bowers, Megan; Jessberger, Sebastian

    2016-07-01

    We here review the existing evidence linking adult hippocampal neurogenesis and human brain function in physiology and disease. Furthermore, we aim to point out where evidence is missing, highlight current promising avenues of investigation, and suggest future tools and approaches to foster the link between life-long neurogenesis and human brain function. Developmental Dynamics 245:702-709, 2016. © 2016 Wiley Periodicals, Inc. PMID:26890418

  8. Human plasma kallikrein-kinin system: Physiological and biochemical parameters

    PubMed Central

    Bryant, J.W.; Shariat-Madar, z

    2016-01-01

    The plasma kallikrein-kinin system (KKS) plays a critical role in human physiology. The KKS encompasses coagulation factor XII (FXII), the complex of prekallikrein (PK) and high molecular weight kininogen (HK). The conversion of plasma to kallikrein by the activated FXII and in response to numerous different stimuli leads to the generation of bradykinin (BK) and activated HK (HKa, an antiangiogenic peptide). BK is a proinflammatory peptide, a pain mediator and potent vasodilator, leading to robust accumulation of fluid in the interstitium. Systemic production of BK, HKa with the interplay between BK bound-BK receptors and the soluble form of HKa are key to angiogenesis and hemodynamics. KKS has been implicated in the pathogenesis of inflammation, hypertension, endotoxemia, and coagulopathy. In all these cases increased BK levels is the hallmark. In some cases, the persistent production of BK due to the deficiency of the blood protein C1-inhibitor, which controls FXII, is detrimental to the survival of the patients with hereditary angioedema (HAE). In others, the inability of angiotensin converting enzyme (ACE) to degrade BK leads to elevated BK levels and edema in patients on ACE inhibitors. Thus, the mechanisms that interfere with BK liberation or degradation would lead to blood pressure dysfunction. In contrast, anti-kallikrein treatment could have adverse effects in hemodynamic changes induced by vasoconstrictor agents. Genetic models of kallikrein deficiency are needed to evaluate the quantitative role of kallikrein and to validate whether strategies designed to activate or inhibit kallikrein may be important for regulating whole-body BK sensitivity. PMID:19689262

  9. Human thermal physiological and psychological responses under different heating environments.

    PubMed

    Wang, Zhaojun; Ning, Haoran; Ji, Yuchen; Hou, Juan; He, Yanan

    2015-08-01

    Anecdotal evidence suggests that many residents of severely cold areas of China who use floor heating (FH) systems feel warmer but drier compared to those using radiant heating (RH) systems. However, this phenomenon has not been verified experimentally. In order to validate the empirical hypothesis, and research the differences of human physiological and psychological responses in these two asymmetrical heating environments, an experiment was designed to mimic FH and RH systems. The subjects participating in the experiment were volunteer college-students. During the experiment, the indoor air temperature, air speed, relative humidity, globe temperature, and inner surface temperatures were measured, and subjects' heart rate, blood pressure and skin temperatures were recorded. The subjects were required to fill in questionnaires about their thermal responses during testing. The results showed that the subjects' skin temperatures, heart rate and blood pressure were significantly affected by the type of heating environment. Ankle temperature had greatest impact on overall thermal comfort relative to other body parts, and a slightly cool FH condition was the most pleasurable environment for sedentary subjects. The overall thermal sensation, comfort and acceptability of FH were higher than that of RH. However, the subjects of FH felt drier than that of RH, although the relative humidity in FH environments was higher than that of the RH environment. In future environmental design, the thermal comfort of the ankles should be scrutinized, and a FH cool condition is recommended as the most comfortable thermal environment for office workers. Consequently, large amounts of heating energy could be saved in this area in the winter. The results of this study may lead to more efficient energy use for office or home heating systems. PMID:26267512

  10. EPM - The European Facility for human physiology research on ISS.

    PubMed

    Rieschel, Mats; Nasca, Rosario; Junk, Peter; Gerhard, Ingo

    2002-07-01

    The European Physiology Modules (EPM) Facility is one of the four major Space Station facilities being developed within the framework of ESA's Microgravity Facilities for Columbus (MFC) programme. In order to allow a wide spectrum of physiological studies in weightlessness conditions, the facility provides the infrastructure to accommodate a variable set of scientific equipment. The initial EPM configuration supports experiments in the fields of neuroscience, bone & muscle research, cardiovascular research and metabolism. The International Space Life Science Working Group (ISLSWG) has recommended co-locating EPM with the 2 NASA Human Research Facility racks. PMID:15002609

  11. [The solidarity of the human body].

    PubMed

    Bioy, Xavier

    2014-06-01

    The legal and bioethical regulation of the uses of the elements of the human body can be described by means of the concept of solidarity. From the French example, we can so show that the State tries to frame solidarities which already exist, for example between people who share the same genome, in the family, or, on the contrary, tent to impose or to direct the sharing of the human biological resources (organs, tissues, gametes, stem cell...). PMID:25272799

  12. An Evaluation of Gestational Exposure to Perfluorooctanoic Acid (PFOA): Effects on Body Composition and Physiological Factors

    EPA Science Inventory

    Exposure to environmental pollutants can be a factor for induction of metabolic disorders. This study examined if exposure to PFOA during development could alter body composition and other physiological outcomes. Study 1: Pregnant CD-1 mice were gavaged with PFOA at 0,0.001,0.01,...

  13. Body Composition and Physiological Responses of Masters Female Swimmers 20 to 70 Years of Age.

    ERIC Educational Resources Information Center

    Vaccaro, Paul; And Others

    1984-01-01

    Female masters swimmers ranging in age from 20 to 69 were chosen for a study of their body composition and physiological responses at rest and during exercise. Two training groups were formed that differed on the basis of frequency, duration, and intensity of swimming workouts. Results are discussed. (Author/DF)

  14. Physiological correlates and emotional specificity of human piloerection.

    PubMed

    Benedek, Mathias; Kaernbach, Christian

    2011-03-01

    Piloerection is known as an indicator of strong emotional experiences. However, little is known about the physiological and emotional specificity of this psychophysiological response. In the presented study, piloerection was elicited by audio stimuli taken from music and film episodes. The physiological response accompanying the incidence of piloerection was recorded with respect to electrodermal, cardiovascular and respiratory measures and compared to a matched control condition. The employment of an optical recording system allowed for a direct and objective assessment of visible piloerection. The occurrence of piloerection was primarily accompanied by an increase of phasic electrodermal activity and increased respiration depth as compared to a matched control condition. This physiological response pattern is discussed in the context of dominant theories of human piloerection. Consideration of all available evidence suggests that emotional piloerection represents a valuable indicator of the state of being moved or touched. PMID:21276827

  15. Physiological correlates and emotional specificity of human piloerection

    PubMed Central

    Benedek, Mathias; Kaernbach, Christian

    2011-01-01

    Piloerection is known as an indicator of strong emotional experiences. However, little is known about the physiological and emotional specificity of this psychophysiological response. In the presented study, piloerection was elicited by audio stimuli taken from music and film episodes. The physiological response accompanying the incidence of piloerection was recorded with respect to electrodermal, cardiovascular and respiratory measures and compared to a matched control condition. The employment of an optical recording system allowed for a direct and objective assessment of visible piloerection. The occurrence of piloerection was primarily accompanied by an increase of phasic electrodermal activity and increased respiration depth as compared to a matched control condition. This physiological response pattern is discussed in the context of dominant theories of human piloerection. Consideration of all available evidence suggests that emotional piloerection represents a valuable indicator of the state of being moved or touched. PMID:21276827

  16. Lower body negative pressure as a tool for research in aerospace physiology and military medicine

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.

    2001-01-01

    Lower body negative pressure (LBNP) has been extensively used for decades in aerospace physiological research as a tool to investigate cardiovascular mechanisms that are associated with or underlie performance in aerospace and military environments. In comparison with clinical stand and tilt tests, LBNP represents a relatively safe methodology for inducing highly reproducible hemodynamic responses during exposure to footward fluid shifts similar to those experienced under orthostatic challenge. By maintaining an orthostatic challenge in a supine posture, removal of leg support (muscle pump) and head motion (vestibular stimuli) during LBNP provides the capability to isolate cardiovascular mechanisms that regulate blood pressure. LBNP can be used for physiological measurements, clinical diagnoses and investigational research comparisons of subject populations and alterations in physiological status. The applications of LBNP to the study of blood pressure regulation in spaceflight, groundbased simulations of low gravity, and hemorrhage have provided unique insights and understanding for development of countermeasures based on physiological mechanisms underlying the operational problems.

  17. Human recognition by body shape features

    NASA Astrophysics Data System (ADS)

    Du, Ming; Guan, Ling

    2005-03-01

    Non-invasive biometrics is of particular importance because of its application under surveillance environment. Although traditional research in this field is mostly focused on gait recognition, feature based on human body shape is one of the alternate choices we can rely on. Here we propose a body shape based identification system, trying to explore the its distinguishing power in biometrics. Robust image processing procedures such as Wiener filter are implemented to extract binary silhouettes from frontal-view human walking video. The Kalman filter, usually adopted as a powerful tool to facilitate tracking in computer vision applications, here functions as a reliable estimator to recover body shape information from the corrupted observations. The dynamically extracted static feature vectors are then compared to templates to achieve identification. We provide experimental results to demonstrate the performance of our system.

  18. Thermodynamics of Cooling a (Live) Human Body.

    ERIC Educational Resources Information Center

    Weinstock, Harold

    1980-01-01

    Presents a practical problem to students in a junior-level thermodynamics course in which a human body regulates its own internal temperature. This problem can be utilized as well (with modification) in an introductory physics course for life science majors. (HM)

  19. Modeling forces on the human body

    NASA Astrophysics Data System (ADS)

    Pagonis, Vasilis; Drake, Russel; Morgan, Michael; Peters, Todd; Riddle, Chris; Rollins, Karen

    1999-11-01

    Several simulations involving the human body, using the simulation software Interactive Physics™, are used to analyze the forces during both static situations and dynamic collisions. The connection of the simulations with the biological sciences and with sports activities should make them appealing to both high school and college-level physics students.

  20. Visuals and Visualisation of Human Body Systems

    ERIC Educational Resources Information Center

    Mathai, Sindhu; Ramadas, Jayashree

    2009-01-01

    This paper explores the role of diagrams and text in middle school students' understanding and visualisation of human body systems. We develop a common framework based on structure and function to assess students' responses across diagram and verbal modes. Visualisation is defined in terms of understanding transformations on structure and relating…

  1. Sunspot Dynamics Are Reflected in Human Physiology and Pathophysiology

    NASA Astrophysics Data System (ADS)

    Hrushesky, William J. M.; Sothern, Robert B.; Du-Quiton, Jovelyn; Quiton, Dinah Faith T.; Rietveld, Wop; Boon, Mathilde E.

    2011-03-01

    Periodic episodes of increased sunspot activity (solar electromagnetic storms) occur with 10-11 and 5-6 year periodicities and may be associated with measurable biological events. We investigated whether this sunspot periodicity characterized the incidence of Pap smear-determined cervical epithelial histopathologies and human physiologic functions. From January 1983 through December 2003, monthly averages were obtained for solar flux and sunspot numbers; six infectious, premalignant and malignant changes in the cervical epithelium from 1,182,421 consecutive, serially independent, screening Pap smears (59°9"N, 4°29"E); and six human physiologic functions of a healthy man (oral temperature, pulse, systolic and diastolic blood pressure, respiration, and peak expiratory flow), which were measured ∼5 times daily during ∼34,500 self-measurement sessions (44°56"N, 93°8"W). After determining that sunspot numbers and solar flux, which were not annually rhythmic, occurred with a prominent 10-year and a less-prominent 5.75-year periodicity during this 21-year study span, each biological data set was analyzed with the same curve-fitting procedures. All six annually rhythmic Pap smear-detected infectious, premalignant and malignant cervical epithelial pathologies showed strong 10-year and weaker 5.75-year cycles, as did all six self-measured, annually rhythmic, physiologic functions. The phases (maxima) for the six histopathologic findings and five of six physiologic measurements were very near, or within, the first two quarters following the 10-year solar maxima. These findings add to the growing evidence that solar magnetic storm periodicities are mirrored by cyclic phase-locked rhythms of similar period length or lengths in human physiology and pathophysiology.

  2. Stretch sensors for human body motion

    NASA Astrophysics Data System (ADS)

    O'Brien, Ben; Gisby, Todd; Anderson, Iain A.

    2014-03-01

    Sensing motion of the human body is a difficult task. From an engineers' perspective people are soft highly mobile objects that move in and out of complex environments. As well as the technical challenge of sensing, concepts such as comfort, social intrusion, usability, and aesthetics are paramount in determining whether someone will adopt a sensing solution or not. At the same time the demands for human body motion sensing are growing fast. Athletes want feedback on posture and technique, consumers need new ways to interact with augmented reality devices, and healthcare providers wish to track recovery of a patient. Dielectric elastomer stretch sensors are ideal for bridging this gap. They are soft, flexible, and precise. They are low power, lightweight, and can be easily mounted on the body or embedded into clothing. From a commercialisation point of view stretch sensing is easier than actuation or generation - such sensors can be low voltage and integrated with conventional microelectronics. This paper takes a birds-eye view of the use of these sensors to measure human body motion. A holistic description of sensor operation and guidelines for sensor design will be presented to help technologists and developers in the space.

  3. Effects of weightlessness on human fluid and electrolyte physiology

    NASA Technical Reports Server (NTRS)

    Leach, Carolyn S.; Johnson, Philip C., Jr.

    1991-01-01

    Skylab and Spacelab data on changes occurring in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. The combined results for all three Spacelab studies show that hyponatremia developed within 20 h after the onset of weightlessness and continued throughout the flights, and hypokalemia developed by 40 h. Antidiuretic hormone was increased in plasma throughout the flights. Aldosterone decreased by 40 h, but after 7 days it had reached preflight levels.

  4. Introduction to anatomy and physiology of human conception.

    PubMed

    Kably, A; Barroso, G

    2000-01-01

    Anatomical and physiological concepts of human reproduction currently in use have been developed over generations, following clinical and basic research guidelines that preceded modern technology. The application of new forms of research over recent decades, as in the case of molecular biology, has contributed to a more in-depth and accurate understanding of the interaction of each of the inter- and intracellular structures in the mechanics of human physiology. On the other hand the use of non-human primate models has provided invaluable information in the reproductive field. The information obtained through models and techniques that have changed over time has led to concepts that continue to have the same validity as when they were first described. The principal objective of this review is to develop an understanding of the physiological processes applied in the anatomical sphere, taking as a reference the fact that it is impossible to understand reproductive mechanics in terms of static phenomena, but rather they should be understood as dynamic and changing processes adaptable to the conditions of each individual's surroundings. PMID:12804191

  5. Electronic imaging of the human body

    NASA Astrophysics Data System (ADS)

    Vannier, Michael W.; Yates, Randall E.; Whitestone, Jennifer J.

    1992-09-01

    The Human Engineering Division of the Armstrong Laboratory (USAF); the Mallinckrodt Institute of Radiology; the Washington University School of Medicine; and the Lister-Hill National Center for Biomedical Communication, National Library of Medicine are sponsoring a working group on electronic imaging of the human body. Electronic imaging of the surface of the human body has been pursued and developed by a number of disciplines including radiology, forensics, surgery, engineering, medical education, and anthropometry. The applications range from reconstructive surgery to computer-aided design (CAD) of protective equipment. Although these areas appear unrelated, they have a great deal of commonality. All the organizations working in this area are faced with the challenges of collecting, reducing, and formatting the data in an efficient and standard manner; storing this data in a computerized database to make it readily accessible; and developing software applications that can visualize, manipulate, and analyze the data. This working group is being established to encourage effective use of the resources of all the various groups and disciplines involved in electronic imaging of the human body surface by providing a forum for discussing progress and challenges with these types of data.

  6. Kinematic analysis of human body motion

    NASA Astrophysics Data System (ADS)

    Wada, Yuhei; Yamashita, Hiroyuki; Nishimura, Tetsu; Itoh, Masaru; Watanabe, Naoki; Yanagi, Shigeru

    1997-03-01

    The knowledge of analyzing a human motion can contribute to the treatment and the prevention of sports injuries or the investigation of welfare equipment. It is important to know the human motion by not only the medical field but the mechanical knowledge. The mechanical knowledge is expected to prevent the sports injuries or to design such as an artificial equipment. Here, we suggest a basic procedure to analyze a human motion from the view of the dynamical knowledge. Although the human body is composed of a lot of element and joint, if the slight movement on the joint such as dislocation and distortion is neglected, the human body can be replaced by a mechanical links system. On this assumption, we analyze an actual simple human motion. We take a picture of a simple arm motion from video cameras. And at the same time, we directly measure the vertical acceleration of the hand by an accelerometer. From the video image, we get the vertical acceleration of the hand with assuming the arm as two-links system. On the process of resolving the vertical acceleration of the hand, we introduce the Fourier series for filtering. Finally, we confirm the propriety of our suggested procedure by comparing the calculated acceleration of hand with the directly measured acceleration.

  7. DigitalHuman (DH): An Integrative Mathematical Model ofHuman Physiology

    NASA Technical Reports Server (NTRS)

    Hester, Robert L.; Summers, Richard L.; lIescu, Radu; Esters, Joyee; Coleman, Thomas G.

    2010-01-01

    Mathematical models and simulation are important tools in discovering the key causal relationships governing physiological processes and improving medical intervention when physiological complexity is a central issue. We have developed a model of integrative human physiology called DigitalHuman (DH) consisting of -5000 variables modeling human physiology describing cardiovascular, renal, respiratory, endocrine, neural and metabolic physiology. Users can view time-dependent solutions and interactively introduce perturbations by altering numerical parameters to investigate new hypotheses. The variables, parameters and quantitative relationships as well as all other model details are described in XML text files. All aspects of the model, including the mathematical equations describing the physiological processes are written in XML open source, text-readable files. Model structure is based upon empirical data of physiological responses documented within the peer-reviewed literature. The model can be used to understand proposed physiological mechanisms and physiological interactions that may not be otherwise intUitively evident. Some of the current uses of this model include the analyses of renal control of blood pressure, the central role of the liver in creating and maintaining insulin resistance, and the mechanisms causing orthostatic hypotension in astronauts. Additionally the open source aspect of the modeling environment allows any investigator to add detailed descriptions of human physiology to test new concepts. The model accurately predicts both qualitative and more importantly quantitative changes in clinically and experimentally observed responses. DigitalHuman provides scientists a modeling environment to understand the complex interactions of integrative physiology. This research was supported by.NIH HL 51971, NSF EPSCoR, and NASA

  8. Physiologic mechanisms effecting circulatory and body fluid losses in weightlessness as shown by mathematical modeling.

    PubMed

    Simanonok, K E; Srinivasan, R S; Charles, J B

    1993-01-01

    The mechanisms causing large body water losses in weightlessness are not clear. It has long been considered that a central volume expansion drives the physiologic adaptation to a reduced total blood volume, with normal blood composition eventually regained. However, inflight venous pressure measures suggest that central volume expansion in weightlessness may be very transient, or that considerable cardiovascular adaptation to fluid shifts occurs on the ground while astronauts wait in the semi-supine pre-launch position. If a central volume stimulus does not persist, other mechanisms must drive the adaptation of circulation to a reduced blood volume and account for body fluid losses. Recent results from the SLS-1 mission suggest that body fluid volumes do not simply decline to new equilibria but that they decrease to a low point, then undergo some recovery. Similar "under-shoots" of body fluid volumes have also been shown in computer simulations, providing confidence in the validity of the model. The purpose of this study was to examine the mechanisms which could explain the loss of body fluids in weightlessness and how a cardiovascular preadaptation countermeasure we previously tested ameliorated body fluid losses. It is assumed that the physiology of head down tilt (HDT) provides a reasonably accurate analog of weightless exposure. PMID:11537415

  9. Soluble HLA in human body fluids.

    PubMed

    Aultman, D; Adamashvili, I; Yaturu, K; Langford, M; Gelder, F; Gautreaux, M; Ghali, G E; McDonald, J

    1999-03-01

    There is a growing body of information about the soluble forms of HLA in serum but there are only a few reports discussing sHLA in other body fluids. We quantitated sHLA-I and sHLA-II concentrations in sweat, saliva and tear samples from five normal individuals with known HLA-phenotypes. We also studied sweat samples from an additional 12 normal nonphenotyped subjects, as well as in CSF of 20 subjects with different illnesses, using solid phase enzyme linked immunoassay. Sweat, saliva and tears from normal subjects were found to contain very low or nondetectable amounts of sHLA-I. In contrast, sHLA-II molecules were found in each of these body fluids, although, with considerable variation between individuals. The presence of sHLA-II in saliva was further confirmed by Western-blotting. It was observed that sHLA-II having molecular mass of 43,900 and 18,100 daltons was comparable with that found in serum from normal individuals. In addition, no association of sHLA-II levels with allospecificities in either body fluid or in serum was apparent. The results of CSF sHLA concentrations in different diseases were as follows: (1) High CSF SHLA-I levels were measured during viral encephylitis (n = 3), while none of these patients contained sHLA-II in CSF; (2) The levels of sHLA-II, but not sHLA-I were elevated in CSF of patients during seizure (n = 6) and of patients with neonatal hepatitis (1 of 2) or with connective tissue disease accompanied with viral infection (n = 2); (3) No CSF sHLA-I or sHLA-II could be detected at polyneuropathy (n = 2), or in patients with syphilis (n = 3), or leukemia (n = 2) with evidence of neurologic involvement of central nervous system. Taken together, it may be concluded that the presence of sHLA in several body fluids is physiologically normal. It appears that sHLA-II is the predominant class of HLA molecules present in different body fluids. We propose that the system responsible for sHLA-II production in various body fluids must involve

  10. How Do Humans Control Physiological Strain during Strenuous Endurance Exercise?

    PubMed Central

    Esteve-Lanao, Jonathan; Lucia, Alejandro; deKoning, Jos J.; Foster, Carl

    2008-01-01

    Background Distance running performance is a viable model of human locomotion. Methodology/Principal Findings To evaluate the physiologic strain during competitions ranging from 5–100 km, we evaluated heart rate (HR) records of competitive runners (n = 211). We found evidence that: 1) physiologic strain (% of maximum HR (%HRmax)) increased in proportional manner relative to distance completed, and was regulated by variations in running pace; 2) the %HRmax achieved decreased with relative distance; 3) slower runners had similar %HRmax response within a racing distance compared to faster runners, and despite differences in pace, the profile of %HRmax during a race was very similar in runners of differing ability; and 4) in cases where there was a discontinuity in the running performance, there was evidence that physiologic effort was maintained for some time even after the pace had decreased. Conclusions/Significance The overall results suggest that athletes are actively regulating their relative physiologic strain during competition, although there is evidence of poor regulation in the case of competitive failures. PMID:18698405

  11. Thermogenic potential and physiological relevance of human epicardial adipose tissue

    PubMed Central

    Chechi, K; Richard, D

    2015-01-01

    Epicardial adipose tissue is a unique fat depot around the heart that shares a close anatomic proximity and vascular supply with the myocardium and coronary arteries. Its accumulation around the heart, measured using various imaging modalities, has been associated with the onset and progression of coronary artery disease in humans. Epicardial adipose tissue is also the only fat depot around the heart that is known to express uncoupling protein 1 at both mRNA and protein levels in the detectable range. Recent advances have further indicated that human epicardial fat exhibits beige fat-like features. Here we provide an overview of the physiological and pathophysiological relevance of human epicardial fat, and further discuss whether its thermogenic properties can serve as a target for the therapeutic management of coronary heart disease in humans. PMID:27152172

  12. Physiology

    ERIC Educational Resources Information Center

    Kay, Ian

    2008-01-01

    Underlying recent developments in health care and new treatments for disease are advances in basic medical sciences. This edition of "Webwatch" focuses on sites dealing with basic medical sciences, with particular attention given to physiology. There is a vast amount of information on the web related to physiology. The sites that are included here…

  13. Urate Handling in the Human Body.

    PubMed

    Hyndman, David; Liu, Sha; Miner, Jeffrey N

    2016-06-01

    Elevated serum urate concentration is the primary cause of gout. Understanding the processes that affect serum urate concentration is important for understanding the etiology of gout and thereby understanding treatment. Urate handing in the human body is a complex system including three major processes: production, renal elimination, and intestinal elimination. A change in any one of these can affect both the steady-state serum urate concentration as well as other urate processes. The remarkable complexity underlying urate regulation and its maintenance at high levels in humans suggests that this molecule could potentially play an interesting role other than as a mere waste product to be eliminated as rapidly as possible. PMID:27105641

  14. Small-Bodied Humans from Palau, Micronesia

    PubMed Central

    Berger, Lee R.; Churchill, Steven E.; De Klerk, Bonita; Quinn, Rhonda L.

    2008-01-01

    Newly discovered fossil assemblages of small bodied Homo sapiens from Palau, Micronesia possess characters thought to be taxonomically primitive for the genus Homo. Background Recent surface collection and test excavation in limestone caves in the rock islands of Palau, Micronesia, has produced a sizeable sample of human skeletal remains dating roughly between 940-2890 cal ybp. Principle Findings Preliminary analysis indicates that this material is important for two reasons. First, individuals from the older time horizons are small in body size even relative to “pygmoid” populations from Southeast Asia and Indonesia, and thus may represent a marked case of human insular dwarfism. Second, while possessing a number of derived features that align them with Homo sapiens, the human remains from Palau also exhibit several skeletal traits that are considered to be primitive for the genus Homo. Significance These features may be previously unrecognized developmental correlates of small body size and, if so, they may have important implications for interpreting the taxonomic affinities of fossil specimens of Homo. PMID:18347737

  15. Mushroom body miscellanea: transgenic Drosophila strains expressing anatomical and physiological sensor proteins in Kenyon cells

    PubMed Central

    Pech, Ulrike; Dipt, Shubham; Barth, Jonas; Singh, Priyanka; Jauch, Mandy; Thum, Andreas S.; Fiala, André; Riemensperger, Thomas

    2013-01-01

    The fruit fly Drosophila melanogaster represents a key model organism for analyzing how neuronal circuits regulate behavior. The mushroom body in the central brain is a particularly prominent brain region that has been intensely studied in several insect species and been implicated in a variety of behaviors, e.g., associative learning, locomotor activity, and sleep. Drosophila melanogaster offers the advantage that transgenes can be easily expressed in neuronal subpopulations, e.g., in intrinsic mushroom body neurons (Kenyon cells). A number of transgenes has been described and engineered to visualize the anatomy of neurons, to monitor physiological parameters of neuronal activity, and to manipulate neuronal function artificially. To target the expression of these transgenes selectively to specific neurons several sophisticated bi- or even multipartite transcription systems have been invented. However, the number of transgenes that can be combined in the genome of an individual fly is limited in practice. To facilitate the analysis of the mushroom body we provide a compilation of transgenic fruit flies that express transgenes under direct control of the Kenyon-cell specific promoter, mb247. The transgenes expressed are fluorescence reporters to analyze neuroanatomical aspects of the mushroom body, proteins to restrict ectopic gene expression to mushroom bodies, or fluorescent sensors to monitor physiological parameters of neuronal activity of Kenyon cells. Some of the transgenic animals compiled here have been published already, whereas others are novel and characterized here for the first time. Overall, the collection of transgenic flies expressing sensor and reporter genes in Kenyon cells facilitates combinations with binary transcription systems and might, ultimately, advance the physiological analysis of mushroom body function. PMID:24065891

  16. Is Lutein a Physiologically Important Ligand for Transthyretin in Humans?

    SciTech Connect

    Liwei Chen

    2003-05-31

    Lutein and zeaxanthin are the only carotenoids accumulated in the macula of the human retina and are known as the macular pigments (MP). These pigments account for the yellow color of the macula and appear to play an important role in protecting against age-related macular degeneration (AMD). The uptake of lutein and zeaxanthin in human eyes is remarkably specific. It is likely that specific transport or binding proteins are involved. The objective is to determine whether transthyretin (TTR) is a transport protein in human plasma and could thus deliver lutein from the blood to the retina. In this study, they used a biosynthetic {sup 13}C-lutein tracer and gas chromatography-combustion interfaced-isotope ratio mass spectrometry (GCC-IRMS) to gain the requisite sensitivity to detect the minute amounts of lutein expected as a physiological ligand for human transthyretin. The biosynthetic {sup 13}C-labeled lutein tracer was purified from algae. Healthy women (n = 4) each ingested 1 mg of {sup 13}C-labeled lutein daily for 3 days and a blood sample was collected 24 hours after the final dose. Plasma TTR was isolated by retinol-binding protein (RBP)-sepharose affinity chromatography and extracted with chloroform. The {sup 13}C/{sup 12}C ratio in the TTR extract was measured by GCC-IRMS. There was no {sup 13}C-lutein enrichment in the pure TTR extract. This result indicated that lutein is not associated with TTR in human plasma after ingestion in physiological amounts. Some hydrophobic compounds with yellow color may bind to human TTR in the plasma. However, this association needs to be further proved by showing specificity. The study provides a new approach for carotenoid-binding protein studies using a stable isotope tracer method combined with the high precision of GCC-IRMS. The mechanism of selective transport, uptake, and accumulation of lutein in human macula remain to be determined.

  17. SCALING THE PHYSIOLOGICAL EFFECTS OF EXPOSURE TO RADIOFREQUENCY ELECTROMAGNETIC RADIATION: CONSEQUENCES OF BODY SIZE

    EPA Science Inventory

    The authors have demonstrated that a comparative analysis of the physiological effects of exposure of laboratory mammals to radiofrequency electromagnetic radiation (RFR) may be useful in predicting exposure thresholds for humans if the effect is assumed to be due only to heating...

  18. The physiology and biochemistry of total body immobilization in animals: A compendium of research. [bibliographies

    NASA Technical Reports Server (NTRS)

    Dorchak, K. J.; Greenleaf, J. E.

    1976-01-01

    Major studies that describe the physiological and biochemical mechanisms which operate during total body restraint (confinement in cages for example) are presented. The metabolism and behavior of various animals used in medical research (dogs, monkeys, rats, fowl) was investigated and wherever possible a detailed annotation for each study is provided under the subheadings: (a) purposes, (b) procedures and methods, (c) results, and (d) conclusions. Selected references are also included.

  19. Human body contour data based activity recognition.

    PubMed

    Myagmarbayar, Nergui; Yuki, Yoshida; Imamoglu, Nevrez; Gonzalez, Jose; Otake, Mihoko; Yu, Wenwei

    2013-01-01

    This research work is aimed to develop autonomous bio-monitoring mobile robots, which are capable of tracking and measuring patients' motions, recognizing the patients' behavior based on observation data, and providing calling for medical personnel in emergency situations in home environment. The robots to be developed will bring about cost-effective, safe and easier at-home rehabilitation to most motor-function impaired patients (MIPs). In our previous research, a full framework was established towards this research goal. In this research, we aimed at improving the human activity recognition by using contour data of the tracked human subject extracted from the depth images as the signal source, instead of the lower limb joint angle data used in the previous research, which are more likely to be affected by the motion of the robot and human subjects. Several geometric parameters, such as, the ratio of height to weight of the tracked human subject, and distance (pixels) between centroid points of upper and lower parts of human body, were calculated from the contour data, and used as the features for the activity recognition. A Hidden Markov Model (HMM) is employed to classify different human activities from the features. Experimental results showed that the human activity recognition could be achieved with a high correct rate. PMID:24111015

  20. The hepatic transcriptome as a window on whole-body physiology and pathophysiology.

    PubMed

    Morgan, Kevin T; Jayyosi, Zaid; Hower, Moira A; Pino, Michael V; Connolly, Timothy M; Kotlenga, Katja; Lin, Jieyi; Wang, Min; Schmidts, Hans-Ludwig; Bonnefoi, Marc S; Elston, Timothy C; Boorman, Gary A

    2005-01-01

    Transcriptomics can be a valuable aid to pathologists. The information derived from microarray studies may soon include the entire transcriptomes of most cell types, tissues and organs for the major species used for toxicology and human disease risk assessment. Gene expression changes observed in such studies relate to every aspect of normal physiology and pathophysiology. When interpreting such data, one is forced to look "far from the lamp post:' and in so doing, face one's ignorance of many areas of biology. The central role of the liver in toxicology, as well as in many aspects of whole-body physiology, makes the hepatic transcriptome an excellent place to start your studies. This article provides data that reveals the effects of fasting and circadian rhythm on the rat hepatic transcriptome, both of which need to be kept in mind when interpreting large-scale gene expression in the liver. Once you become comfortable with evaluating mRNA expression profiles and learn to correlate these data with your clinical and morphological observations, you may wonder why you did not start your studies of transcriptomics sooner. Additional study data can be viewed at the journal website at (www.toxpath.org). Two data files are provided in Excel format, which contain the control animal data from each of the studies referred to in the text,including normalized signal intensity data for each animal (n=5) in the 6-hour, 24-hour, and 5-day time points. These files are briefly described in the associated 'Readme' file, and the complete list of GenBank numbers and Affymetrix IDs are provided in a separate txt file. These files are available at http://taylorandfrancis.metapress.comlopenurl.asp?genre=journal&issn=0192-6233. Click on the issue link for 33(1), then select this article. A download option appears at the bottom of this abstract. In order to access the full article online, you must either have an individual subscription or a member subscription accessed through (www

  1. Physiological effects of light on the human circadian pacemaker

    NASA Technical Reports Server (NTRS)

    Shanahan, T. L.; Czeisler, C. A.

    2000-01-01

    The physiology of the human circadian pacemaker and its influence and on the daily organization of sleep, endocrine and behavioral processes is an emerging interest in science and medicine. Understanding the development, organization and fundamental properties underlying the circadian timing system may provide insight for the application of circadian principles to the practice of clinical medicine, both diagnostically (interpretation of certain clinical tests are dependent on time of day) and therapeutically (certain pharmacological responses vary with the time of day). The light-dark cycle is the most powerful external influence acting upon the human circadian pacemaker. It has been shown that timed exposure to light can both synchronize and reset the phase of the circadian pacemaker in a predictable manner. The emergence of detectable circadian rhythmicity in the neonatal period is under investigation (as described elsewhere in this issue). Therefore, the pattern of light exposure provided in the neonatal intensive care setting has implications. One recent study identified differences in both amount of sleep time and weight gain in infants maintained in a neonatal intensive care environment that controlled the light-dark cycle. Unfortunately, neither circadian phase nor the time of day has been considered in most clinical investigations. Further studies with knowledge of principles characterizing the human circadian timing system, which governs a wide array of physiological processes, are required to integrate these findings with the practice of clinical medicine.

  2. Three-Dimensional cryoEM Reconstruction of Native LDL Particles to 16Å Resolution at Physiological Body Temperature

    PubMed Central

    Kumar, Vibhor; Butcher, Sarah J.; Öörni, Katariina; Engelhardt, Peter; Heikkonen, Jukka; Kaski, Kimmo; Ala-Korpela, Mika; Kovanen, Petri T.

    2011-01-01

    Background Low-density lipoprotein (LDL) particles, the major carriers of cholesterol in the human circulation, have a key role in cholesterol physiology and in the development of atherosclerosis. The most prominent structural components in LDL are the core-forming cholesteryl esters (CE) and the particle-encircling single copy of a huge, non-exchangeable protein, the apolipoprotein B-100 (apoB-100). The shape of native LDL particles and the conformation of native apoB-100 on the particles remain incompletely characterized at the physiological human body temperature (37°C). Methodology/Principal Findings To study native LDL particles, we applied cryo-electron microscopy to calculate 3D reconstructions of LDL particles in their hydrated state. Images of the particles vitrified at 6°C and 37°C resulted in reconstructions at ∼16 Å resolution at both temperatures. 3D variance map analysis revealed rigid and flexible domains of lipids and apoB-100 at both temperatures. The reconstructions showed less variability at 6°C than at 37°C, which reflected increased order of the core CE molecules, rather than decreased mobility of the apoB-100. Compact molecular packing of the core and order in a lipid-binding domain of apoB-100 were observed at 6°C, but not at 37°C. At 37°C we were able to highlight features in the LDL particles that are not clearly separable in 3D maps at 6°C. Segmentation of apoB-100 density, fitting of lipovitellin X-ray structure, and antibody mapping, jointly revealed the approximate locations of the individual domains of apoB-100 on the surface of native LDL particles. Conclusions/Significance Our study provides molecular background for further understanding of the link between structure and function of native LDL particles at physiological body temperature. PMID:21573056

  3. Animal physiology. Summer declines in activity and body temperature offer polar bears limited energy savings.

    PubMed

    Whiteman, J P; Harlow, H J; Durner, G M; Anderson-Sprecher, R; Albeke, S E; Regehr, E V; Amstrup, S C; Ben-David, M

    2015-07-17

    Polar bears (Ursus maritimus) summer on the sea ice or, where it melts, on shore. Although the physiology of "ice" bears in summer is unknown, "shore" bears purportedly minimize energy losses by entering a hibernation-like state when deprived of food. Such a strategy could partially compensate for the loss of on-ice foraging opportunities caused by climate change. However, here we report gradual, moderate declines in activity and body temperature of both shore and ice bears in summer, resembling energy expenditures typical of fasting, nonhibernating mammals. Also, we found that to avoid unsustainable heat loss while swimming, bears employed unusual heterothermy of the body core. Thus, although well adapted to seasonal ice melt, polar bears appear susceptible to deleterious declines in body condition during the lengthening period of summer food deprivation. PMID:26185248

  4. Nutrition and human physiological adaptations to space flight

    NASA Technical Reports Server (NTRS)

    Lane, H. W.; LeBlanc, A. D.; Putcha, L.; Whitson, P. A.

    1993-01-01

    Space flight provides a model for the study of healthy individuals undergoing unique stresses. This review focuses on how physiological adaptations to weightlessness may affect nutrient and food requirements in space. These adaptations include reductions in body water and plasma volume, which affect the renal and cardiovascular systems and thereby fluid and electrolyte requirements. Changes in muscle mass and function may affect requirements for energy, protein and amino acids. Changes in bone mass lead to increased urinary calcium concentrations, which may increase the risk of forming renal stones. Space motion sickness may influence putative changes in gastro-intestinal-hepatic function; neurosensory alterations may affect smell and taste. Some or all of these effects may be ameliorated through the use of specially designed dietary countermeasures.

  5. Nutrition and human physiological adaptations to space flight.

    PubMed

    Lane, H W; LeBlanc, A D; Putcha, L; Whitson, P A

    1993-11-01

    Space flight provides a model for the study of healthy individuals undergoing unique stresses. This review focuses on how physiological adaptations to weightlessness may affect nutrient and food requirements in space. These adaptations include reductions in body water and plasma volume, which affect the renal and cardiovascular systems and thereby fluid and electrolyte requirements. Changes in muscle mass and function may affect requirements for energy, protein and amino acids. Changes in bone mass lead to increased urinary calcium concentrations, which may increase the risk of forming renal stones. Space motion sickness may influence putative changes in gastro-intestinal-hepatic function; neurosensory alterations may affect smell and taste. Some or all of these effects may be ameliorated through the use of specially designed dietary countermeasures. PMID:8237860

  6. Effects of room temperature on physiological and subjective responses during whole-body bathing, half-body bathing and showering.

    PubMed

    Hashiguchi, Nobuko; Ni, Furong; Tochihara, Yutaka

    2002-11-01

    The effects of bathroom thermal conditions on physiological and subjective responses were evaluated before, during, and after whole-body bath (W-bath), half-body bath (H-bath) and showering. The air temperature of the dressing room and bathroom was controlled at 10 degrees C, 17.5 degrees C, and 25 degrees C. Eight healthy males bathed for 10 min under nine conditions on separate days. The water temperature of the bathtub and shower was controlled at 40 degrees C and 41 degrees C, respectively. Rectal temperature (Tre), mean skin temperature (Tsk), blood pressure (BP), heart rate (HR), body weight loss and blood characteristics (hematocrit: Hct, hemoglobin: Hb) were evaluated. Also, thermal sensation (TS), thermal comfort (TC) and thermal acceptability (TA) were recorded. BP decreased rapidly during W-bath and H-bath compared to showering. HR during W-bath was significantly higher than for H-bath and showering (p < 0.01). The double products due to W-bath during bathing were also greater than for H-bath and showering (p < 0.05). There were no distinct differences in Hct and Hb among the nine conditions. However, significant differences in body weight loss were observed among the bathing methods: W-bath > H-bath > showering (p < 0.001). W-bath showed the largest increase in Tre and Tsk, followed by H-bath, and showering. Significant differences in Tre after bathing among the room temperatures were found only at H-bath. The changes in Tre after bathing for H-bath at 25 degrees C were similar to those for W-bath at 17.5 degrees C and 10 degrees C. TS and TC after bathing significantly differed for the three bathing methods at 17.5 degrees C and 10 degrees C (TS: p < 0.01 TC: p < 0.001). Especially, for showering, the largest number of subjects felt "cold" and "uncomfortable". Even though all of the subjects could accept the 10 degrees C condition after W-bath, such conditions were intolerable to half of them after showering. These results suggested that the

  7. The Physiological Period Length of the Human Circadian Clock In Vivo Is Directly Proportional to Period in Human Fibroblasts

    PubMed Central

    Moriggi, Ermanno; Revell, Victoria L.; Hack, Lisa M.; Lockley, Steven W.; Arendt, Josephine; Skene, Debra J.; Meier, Fides; Izakovic, Jan; Wirz-Justice, Anna; Cajochen, Christian; Sergeeva, Oksana J.; Cheresiz, Sergei V.; Danilenko, Konstantin V.; Eckert, Anne; Brown, Steven A.

    2010-01-01

    Background Diurnal behavior in humans is governed by the period length of a circadian clock in the suprachiasmatic nuclei of the brain hypothalamus. Nevertheless, the cell-intrinsic mechanism of this clock is present in most cells of the body. We have shown previously that for individuals of extreme chronotype (“larks” and “owls”), clock properties measured in human fibroblasts correlated with extreme diurnal behavior. Methodology/Principal Findings In this study, we have measured circadian period in human primary fibroblasts taken from normal individuals and, for the first time, compared it directly with physiological period measured in vivo in the same subjects. Human physiological period length was estimated via the secretion pattern of the hormone melatonin in two different groups of sighted subjects and one group of totally blind subjects, each using different methods. Fibroblast period length was measured via cyclical expression of a lentivirally delivered circadian reporter. Within each group, a positive linear correlation was observed between circadian period length in physiology and in fibroblast gene expression. Interestingly, although blind individuals showed on average the same fibroblast clock properties as sighted ones, their physiological periods were significantly longer. Conclusions/Significance We conclude that the period of human circadian behaviour is mostly driven by cellular clock properties in normal individuals and can be approximated by measurement in peripheral cells such as fibroblasts. Based upon differences among sighted and blind subjects, we also speculate that period can be modified by prolonged unusual conditions such as the total light deprivation of blindness. PMID:21042402

  8. Isomap transform for segmenting human body shapes.

    PubMed

    Cerveri, P; Sarro, K J; Marchente, M; Barros, R M L

    2011-09-01

    Segmentation of the 3D human body is a very challenging problem in applications exploiting volume capture data. Direct clustering in the Euclidean space is usually complex or even unsolvable. This paper presents an original method based on the Isomap (isometric feature mapping) transform of the volume data-set. The 3D articulated posture is mapped by Isomap in the pose of Da Vinci's Vitruvian man. The limbs are unrolled from each other and separated from the trunk and pelvis, and the topology of the human body shape is recovered. In such a configuration, Hoshen-Kopelman clustering applied to concentric spherical shells is used to automatically group points into the labelled principal curves. Shepard interpolation is utilised to back-map points of the principal curves into the original volume space. The experimental results performed on many different postures have proved the validity of the proposed method. Reliability of less than 2 cm and 3° in the location of the joint centres and direction axes of rotations has been obtained, respectively, which qualifies this procedure as a potential tool for markerless motion analysis. PMID:21360362

  9. Measurements, modeling, control and simulation - as applied to the human left ventricle for purposeful physiological monitoring.

    NASA Technical Reports Server (NTRS)

    Ghista, D. N.; Rasmussen, D. N.; Linebarger, R. N.; Sandler, H.

    1971-01-01

    Interdisciplinary engineering research effort in studying the intact human left ventricle has been employed to physiologically monitor the heart and to obtain its 'state-of-health' characteristics. The left ventricle was selected for this purpose because it plays a key role in supplying energy to the body cells. The techniques for measurement of the left ventricular geometry are described; the geometry is effectively displayed to bring out the abnormalities in cardiac function. Methods of mathematical modeling, which make it possible to determine the performance of the intact left ventricular muscle, are also described. Finally, features of a control system for the left ventricle for predicting the effect of certain physiological stress situations on the ventricle performance are discussed.

  10. Engineering physiologically stiff and stratified human cartilage by fusing condensed mesenchymal stem cells

    PubMed Central

    Bhumiratana, Sarindr; Vunjak-Novakovic, Gordana

    2015-01-01

    For a long time, clinically sized and mechanically functional cartilage could be engineered from young animal chondrocytes, but not from adult human mesenchymal stem cells that are of primary clinical interest. The approaches developed for primary chondrocytes were not successful when used with human mesenchymal cells. The method discussed here was designed to employ a mechanism similar to pre-cartilaginous condensation and fusion of mesenchymal stem cells at a precisely defined time. The formation of cartilage was initiated by press-molding the mesenchymal bodies onto the surface of a bone substrate. By image-guided fabrication of the bone substrate and the molds, the osteochondral constructs were engineered in anatomically precise shapes and sizes. After 5 weeks of cultivation, the cartilage layer assumed physiologically stratified histomorphology, and contained lubricin at the surface, proteoglycans and type II collagen in the bulk phase, collagen type X at the interface with the bone substrate, and collagen type I within the bone phase. For the first time, the Young’s modulus and the friction coefficient of human cartilage engineered from mesenchymal stem cells reached physiological levels for adult human cartilage. We propose that this method can be effective for generating human osteochondral tissue constructs. PMID:25828645

  11. Modeling physiological and pathological human neurogenesis in the dish

    PubMed Central

    Broccoli, Vania; Giannelli, Serena G.; Mazzara, Pietro G.

    2014-01-01

    New advances in directing the neuronal differentiation of human embryonic and induced pluripotent stem cells (hPSCs, abbreviation intended to convey both categories of pluripotent stem cells) have promoted the development of culture systems capable of modeling early neurogenesis and neural specification at some of their critical milestones. The hPSC-derived neural rosette can be considered the in vitro counterpart of the developing neural tube, since both structures share a virtually equivalent architecture and related functional properties. Epigenetic stimulation methods can modulate the identity of the rosette neural progenitors in order to generate authentic neuronal subtypes, as well as a full spectrum of neural crest derivatives. The intrinsic capacity of induced pluripotent cell-derived neural tissue to self-organize has become fully apparent with the emergence of innovative in vitro systems that are able to shape the neuronal differentiation of hPSCs into organized tissues that develop in three dimensions. However, significant hurdles remain that must be completely solved in order to facilitate the use of hPSCs in modeling (e.g., late-onset disorders) or in building therapeutic strategies for cell replacement. In this direction, new procedures have been established to promote the maturation and functionality of hPSC-derived neurons. Meanwhile, new methods to accelerate the aging of in vitro differentiating cells are still in development. hPSC-based technology has matured enough to offer a significant and reliable model system for early and late neurogenesis that could be extremely informative for the study of the physiological and pathological events that occur during this process. Thus, full exploitation of this cellular system can provide a better understanding of the physiological events that shape human brain structures, as well as a solid platform to investigate the pathological mechanisms at the root of human diseases. PMID:25104921

  12. Using physiologically-based pharmacokinetic-guided "body-on-a-chip" systems to predict mammalian response to drug and chemical exposure.

    PubMed

    Sung, Jong Hwan; Srinivasan, Balaji; Esch, Mandy Brigitte; McLamb, William T; Bernabini, Catia; Shuler, Michael L; Hickman, James J

    2014-09-01

    The continued development of in vitro systems that accurately emulate human response to drugs or chemical agents will impact drug development, our understanding of chemical toxicity, and enhance our ability to respond to threats from chemical or biological agents. A promising technology is to build microscale replicas of humans that capture essential elements of physiology, pharmacology, and/or toxicology (microphysiological systems). Here, we review progress on systems for microscale models of mammalian systems that include two or more integrated cellular components. These systems are described as a "body-on-a-chip", and utilize the concept of physiologically-based pharmacokinetic (PBPK) modeling in the design. These microscale systems can also be used as model systems to predict whole-body responses to drugs as well as study the mechanism of action of drugs using PBPK analysis. In this review, we provide examples of various approaches to construct such systems with a focus on their physiological usefulness and various approaches to measure responses (e.g. chemical, electrical, or mechanical force and cellular viability and morphology). While the goal is to predict human response, other mammalian cell types can be utilized with the same principle to predict animal response. These systems will be evaluated on their potential to be physiologically accurate, to provide effective and efficient platform for analytics with accessibility to a wide range of users, for ease of incorporation of analytics, functional for weeks to months, and the ability to replicate previously observed human responses. PMID:24951471

  13. Examination of Duct Physiology in the Human Mammary Gland

    PubMed Central

    Mills, Dixie; Gomberawalla, Ameer; Gordon, Eva J.; Tondre, Julie; Nejad, Mitra; Nguyen, Tinh; Pogoda, Janice M.; Rao, Jianyu; Chatterton, Robert; Henning, Susanne; Love, Susan M.

    2016-01-01

    Background The human breast comprise several ductal systems, or lobes, which contain a small amount of fluid containing cells, hormones, proteins and metabolites. The complex physiology of these ducts is likely a contributing factor to the development of breast cancer, especially given that the vast majority of breast cancers begin in a single lobular unit. Methods We examined the levels of total protein, progesterone, estradiol, estrone sulfate, dehydroepiandrosterone sulfate, and macrophages in ductal fluid samples obtained from 3 ducts each in 78 women, sampled twice over a 6 month period. Samples were processed for both cytological and molecular analysis. Intraclass correlation coefficients and mixed models were utilized to identify significant data. Results We found that the levels of these ductal fluid components were generally uncorrelated among ducts within a single breast and over time, suggesting that each lobe within the breast has a distinct physiology. However, we also found that estradiol was more correlated in women who were nulliparous or produced nipple aspirate fluid. Conclusions Our results provide evidence that the microenvironment of any given lobular unit is unique to that individual unit, findings that may provide clues about the initiation and development of ductal carcinomas. PMID:27073976

  14. User Interactive Software for Analysis of Human Physiological Data

    NASA Technical Reports Server (NTRS)

    Cowings, Patricia S.; Toscano, William; Taylor, Bruce C.; Acharya, Soumydipta

    2006-01-01

    Ambulatory physiological monitoring has been used to study human health and performance in space and in a variety of Earth-based environments (e.g., military aircraft, armored vehicles, small groups in isolation, and patients). Large, multi-channel data files are typically recorded in these environments, and these files often require the removal of contaminated data prior to processing and analyses. Physiological data processing can now be performed with user-friendly, interactive software developed by the Ames Psychophysiology Research Laboratory. This software, which runs on a Windows platform, contains various signal-processing routines for both time- and frequency- domain data analyses (e.g., peak detection, differentiation and integration, digital filtering, adaptive thresholds, Fast Fourier Transform power spectrum, auto-correlation, etc.). Data acquired with any ambulatory monitoring system that provides text or binary file format are easily imported to the processing software. The application provides a graphical user interface where one can manually select and correct data artifacts utilizing linear and zero interpolation and adding trigger points for missed peaks. Block and moving average routines are also provided for data reduction. Processed data in numeric and graphic format can be exported to Excel. This software, PostProc (for post-processing) requires the Dadisp engineering spreadsheet (DSP Development Corp), or equivalent, for implementation. Specific processing routines were written for electrocardiography, electroencephalography, electromyography, blood pressure, skin conductance level, impedance cardiography (cardiac output, stroke volume, thoracic fluid volume), temperature, and respiration

  15. Has cervical smooth muscle any physiological role in the human?

    PubMed

    Bryman, I; Norström, A; Lindblom, B

    1985-01-01

    Strips of human cervical tissue were obtained by needle biopsy and contractile activity was registered isometrically in a tissue chamber perfused by Krebs-Ringer bicarbonate buffer. The most frequently encountered pattern of contractile activity was high frequency-short duration. Prostaglandin (PG)E2, PGI2 and 6-keto-PGF1 alpha had an inhibitory effect on the muscular activity. Cervical muscle from pregnant women was more sensitive to PGE2 than specimens from non-pregnant women. PGF2 alpha had no apparent effect on cervical contractility in non-pregnant and early pregnant patients. In late pregnancy, however, PGF2 alpha inhibited muscle contractions. The present results point to a physiological role of the cervical muscles for the control of cervical competence during pregnancy. The inhibitory effect of PGs on the muscle activity may promote cervical dilatation and retraction. PMID:3893038

  16. Development of a Physiological Model for the Human Spine

    NASA Astrophysics Data System (ADS)

    Kvitnitsky, Michael; Thangam, Siva

    2011-11-01

    The intervertebral disc in a human spine is a complex structure consisting of three distinct parts: the nucleus pulposus, the annulus fibrosus, and the cartilaginous end-plates. The Nucleus Pulposus is centrally located within the disc surrounded by annulus fibrosus. It consists of a loose network of fibers and cells in a proteoglycan gel, which merges indistinctly at its outer margin with the annulus fibrosus. A viscoelastic constitutive model is proposed for the nucleus pulposus of the human spine to facilitate the development of a flexible intervetebral device designed for application in the thoraco-lumbar region of the human spine during surgery. A novel experimental set up was designed to establish application limits of the design concept for different approaches in spinal surgery. Both static and fatigue mechanical tests based on the ASTM standards provided a basis for the comparison with some existing clinically successful spinal implants designed for similar applications. Also, these mechanical tests and in-vitro comparison with normal spine provided the application limits of this design in surgery to maintain physiologic functional performance at the affected spinal level. The model is used to investigate the effect of the various design parameters on the biomechanical environment of the spine segment.

  17. Physiological and biomechanical considerations for a human Mars mission.

    PubMed

    Hawkey, Adam

    2005-01-01

    Evolving on Earth has made humans perfectly adapted, both physiologically and biomechanically, to its gravity and atmospheric conditions. Leaving the Earth and its protective environment, therefore, results in the degradation of a number of human systems. Long-duration stays on the International Space Station (ISS) are accompanied by significant effects on crew's cardiovascular, vestibular and musculoskeletal systems. Bone loss and muscle atrophy are experienced at a rate of 1-3% and 5% per month respectively, while VO2 (oxygen consumption) measurements are reduced by approximately 25% after a few weeks in space. If these figures are simply extrapolated, a future human mission to Mars will be seriously jeopardised and crews may find they cross the threshold of bone and muscle loss and aerobic fitness--ultimately with them being unable to return to Earth. When arriving on Mars, considerable biomechanical alterations will also occur. Optimum walking speeds will be approximately 30% lower and transitioning from a walk to a run will occur at a speed 25% slower. Peak vertical forces will be reduced by as much as 50%, while stride length, stride time and airborne time will all increase. On Mars, half as much energy will be required to travel the equivalent distance on Earth and it will be 65% more economical to run rather than to walk. PMID:15852539

  18. Physiological and Biomechanical Considerations for a Human Mars Mission

    NASA Astrophysics Data System (ADS)

    Hawkey, A.

    Evolving on Earth has made humans perfectly adapted, both physiologically and biomechanically, to its gravity and atmospheric conditions. Leaving the Earth and its protective environment, therefore, results in the degradation of a number of human systems. Long-duration stays on the International Space Station (ISS) are accompanied by significant effects on crew's cardiovascular, vestibular and musculoskeletal systems. Bone loss and muscle atrophy are experienced at a rate of 1-3% and 5% per month respectively, while VO2 (oxygen consumption) measurements are reduced by approximately 25% after a few weeks in space. If these figures are simply extrapolated, a future human mission to Mars will be seriously jeopardised and crews may find they cross the threshold of bone and muscle loss and aerobic fitness - ultimately with them being unable to return to Earth. When arriving on Mars, considerable biomechanical alterations will also occur. Optimum walking speeds will be approximately 30% lower and transitioning from a walk to a run will occur at a speed 25% slower. Peak vertical forces will be reduced by as much as 50%, while stride length, stride time and airborne time will all increase. On Mars, half as much energy will be required to travel the equivalent distance on Earth and it will be 65% more economical to run rather than to walk.

  19. Anatomical and physiological development of the human inner ear.

    PubMed

    Lim, Rebecca; Brichta, Alan M

    2016-08-01

    We describe the development of the human inner ear with the invagination of the otic vesicle at 4 weeks gestation (WG), the growth of the semicircular canals from 5 WG, and the elongation and coiling of the cochlea at 10 WG. As the membranous labyrinth takes shape, there is a concomitant development of the sensory neuroepithelia and their associated structures within. This review details the growth and differentiation of the vestibular and auditory neuroepithelia, including synaptogenesis, the expression of stereocilia and kinocilia, and innervation of hair cells by afferent and efferent nerve fibres. Along with development of essential sensory structures we outline the formation of crucial accessory structures of the vestibular system - the cupula and otolithic membrane and otoconia as well as the three cochlea compartments and the tectorial membrane. Recent molecular studies have elaborated on classical anatomical studies to characterize the development of prosensory and sensory regions of the fetal human cochlea using the transcription factors, PAX2, MAF-B, SOX2, and SOX9. Further advances are being made with recent physiological studies that are beginning to describe when hair cells become functionally active during human gestation. This article is part of a Special Issue entitled . PMID:26900072

  20. Determinants of body weight regulation in humans.

    PubMed

    Moehlecke, Milene; Canani, Luis Henrique; Silva, Lucas Oliveira Junqueira E; Trindade, Manoel Roberto Maciel; Friedman, Rogerio; Leitão, Cristiane Bauermann

    2016-04-01

    Body weight is regulated by the ability of hypothalamic neurons to orchestrate behavioral, endocrine and autonomic responses via afferent and efferent pathways to the brainstem and the periphery. Weight maintenance requires a balance between energy intake and energy expenditure. Although several components that participate in energy homeostasis have been identified, there is a need to know in more detail their actions as well as their interactions with environmental and psychosocial factors in the development of human obesity. In this review, we examine the role of systemic mediators such as leptin, ghrelin and insulin, which act in the central nervous system by activating or inhibiting neuropeptide Y, Agouti-related peptide protein, melanocortin, transcript related to cocaine and amphetamine, and others. As a result, modifications in energy homeostasis occur through regulation of appetite and energy expenditure. We also examine compensatory changes in the circulating levels of several peripheral hormones after diet-induced weight loss. PMID:26910628

  1. Simulating the physiology of athletes during endurance sports events: modelling human energy conversion and metabolism

    PubMed Central

    van Beek, Johannes H. G. M.; Supandi, Farahaniza; Gavai, Anand K.; de Graaf, Albert A.; Binsl, Thomas W.; Hettling, Hannes

    2011-01-01

    The human physiological system is stressed to its limits during endurance sports competition events. We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We calculated heat transfer by conduction and blood flow inside the body, and heat transfer from the skin by radiation, convection and sweat evaporation, resulting in temperature changes in 25 body compartments. We simulated a mountain time trial to Alpe d'Huez during the Tour de France. To approach the time realized by Lance Armstrong in 2004, very high oxygen uptake must be sustained by the simulated cyclist. Temperature was predicted to reach 39°C in the brain, and 39.7°C in leg muscle. In addition to the macroscopic simulation, we analysed the buffering of bursts of high adenosine triphosphate hydrolysis by creatine kinase during cyclical muscle activity at the biochemical pathway level. To investigate the low oxygen to carbohydrate ratio for the brain, which takes up lactate during exercise, we calculated the flux distribution in cerebral energy metabolism. Computational modelling of the human body, describing heat exchange and energy metabolism, makes simulation of endurance sports events feasible. PMID:21969677

  2. Physiologic mechanisms of circulatory and body fluid losses in weightlessness identified by mathematical modeling

    NASA Technical Reports Server (NTRS)

    Simanonok, K. E.; Srinivasan, R. S.; Charles, J. B.

    1993-01-01

    Central volume expansion due to fluid shifts in weightlessness is believed to activate adaptive reflexes which ultimately result in a reduction of the total circulating blood volume. However, the flight data suggests that a central volume overdistention does not persist, in which case some other factor or factors must be responsible for body fluid losses. We used a computer simulation to test the hypothesis that factors other than central volume overdistention are involved in the loss of blood volume and other body fluid volumes observed in weightlessness and in weightless simulations. Additionally, the simulation was used to identify these factors. The results predict that atrial volumes and pressures return to their prebedrest baseline values within the first day of exposure to head down tilt (HDT) as the blood volume is reduced by an elevated urine formation. They indicate that the mechanisms for large and prolonged body fluid losses in weightlessness is red cell hemoconcentration that elevates blood viscosity and peripheral resistance, thereby lowering capillary pressure. This causes a prolonged alteration of the balance of Starling forces, depressing the extracellular fluid volume until the hematocrit is returned to normal through a reduction of the red cell mass, which also allows some restoration of the plasma volume. We conclude that the red cell mass becomes the physiologic driver for a large 'undershoot' of the body fluid volumes after the normalization of atrial volumes and pressures.

  3. Physiological variables affecting surface film formation by native lamellar body-like pulmonary surfactant particles.

    PubMed

    Hobi, Nina; Siber, Gerlinde; Bouzas, Virginia; Ravasio, Andrea; Pérez-Gil, Jesus; Haller, Thomas

    2014-07-01

    Pulmonary surfactant (PS) is a surface active complex of lipids and proteins that prevents the alveolar structures from collapsing and reduces the work of breathing by lowering the surface tension at the alveolar air-liquid interface (ALI). Surfactant is synthesized by the alveolar type II (AT II) cells, and it is stored in specialized organelles, the lamellar bodies (LBs), as tightly packed lipid bilayers. Upon secretion into the alveolar lining fluid, a large fraction of these particles retain most of their packed lamellar structure, giving rise to the term lamellar body like-particles (LBPs). Due to their stability in aqueous media, freshly secreted LBPs can be harvested from AT II cell preparations. However, when LBPs get in contact with an ALI, they quickly and spontaneously adsorb into a highly organized surface film. In the present study we investigated the adsorptive capacity of LBPs at an ALI under relevant physiological parameters that characterize the alveolar environment in homeostatic or in pathological conditions. Adsorption of LBPs at an ALI is highly sensitive to pH, temperature and albumin concentration and to a relatively lesser extent to changes in osmolarity or Ca(2+) concentrations in the physiological range. Furthermore, proteolysis of LBPs significantly decreases their adsorptive capacity confirming the important role of surfactant proteins in the formation of surface active films. PMID:24582711

  4. Origins and early development of human body knowledge.

    PubMed

    Slaughter, Virginia; Heron, Michelle

    2004-01-01

    As a knowable object, the human body is highly complex. Evidence from several converging lines of research, including psychological studies, neuroimaging and clinical neuropsychology, indicates that human body knowledge is widely distributed in the adult brain, and is instantiated in at least three partially independent levels of representation. Sensorimotor body knowledge is responsible for on-line control and movement of one's own body and may also contribute to the perception of others' moving bodies; visuo-spatial body knowledge specifies detailed structural descriptions of the spatial attributes of the human body; and lexical-semantic body knowledge contains language-based knowledge about the human body. In the first chapter of this Monograph, we outline the evidence for these three hypothesized levels of human body knowledge, then review relevant literature on infants' and young children's human body knowledge in terms of the three-level framework. In Chapters II and III, we report two complimentary series of studies that specifically investigate the emergence of visuo-spatial body knowledge in infancy. Our technique is to compare infants'responses to typical and scrambled human bodies, in order to evaluate when and how infants acquire knowledge about the canonical spatial layout of the human body. Data from a series of visual habituation studies indicate that infants first discriminate scrambled from typical human body picture sat 15 to 18 months of age. Data from object examination studies similarly indicate that infants are sensitive to violations of three-dimensional human body stimuli starting at 15-18 months of age. The overall pattern of data supports several conclusions about the early development of human body knowledge: (a) detailed visuo-spatial knowledge about the human body is first evident in the second year of life, (b) visuo-spatial knowledge of human faces and human bodies are at least partially independent in infancy and (c) infants' initial

  5. Adiposity and human regional body temperature123

    PubMed Central

    Savastano, David M; Gorbach, Alexander M; Eden, Henry S; Brady, Sheila M; Reynolds, James C

    2009-01-01

    Background: Human obesity is associated with increased heat production; however, subcutaneous adipose tissue provides an insulating layer that impedes heat loss. To maintain normothermia, therefore, obese individuals must increase their heat dissipation. Objective: The objective was to test the hypothesis that temperature in a heat-dissipating region of the hand is elevated in obese adults. Design: Obese [body mass index (in kg/m2) ≥ 30] and normal-weight (NW; body mass index = 18–25) adults were studied under thermoneutral conditions at rest. Core body temperature was measured by using ingested telemetric capsules. The temperatures of the third fingernail bed of the right hand and of abdominal skin from an area 1.5 cm inferior to the umbilicus were determined by using infrared thermography. Abdominal skin temperatures were also measured via adhesive thermistors that were placed over a prominent skin-surface blood vessel and over an adjacent nonvessel location. The groups were compared by analysis of covariance with age, sex, race, and room temperature as covariates. Results: Core temperature did not differ significantly between the 23 obese and 13 NW participants (P = 0.74). However, infrared thermography–measured fingernail-bed temperature was significantly higher in obese subjects than in NW subjects (33.9 ± 0.7°C compared with 28.6 ± 0.9°C; P < 0.001). Conversely, infrared thermography–measured abdominal skin temperature was significantly lower in obese subjects than in NW subjects (31.8 ± 0.2°C compared with 32.8 ± 0.3°C; P = 0.02). Nonvessel abdominal skin temperatures measured by thermistors were also lower in obese subjects (P = 0.04). Conclusions: Greater subcutaneous abdominal adipose tissue in obese adults may provide a significant insulating layer that blunts abdominal heat transfer. Augmented heat release from the hands may offset heat retention in areas of the body with greater adiposity, thereby helping to maintain normothermia in

  6. A multi-tissue type genome-scale metabolic network for analysis of whole-body systems physiology

    PubMed Central

    2011-01-01

    Background Genome-scale metabolic reconstructions provide a biologically meaningful mechanistic basis for the genotype-phenotype relationship. The global human metabolic network, termed Recon 1, has recently been reconstructed allowing the systems analysis of human metabolic physiology and pathology. Utilizing high-throughput data, Recon 1 has recently been tailored to different cells and tissues, including the liver, kidney, brain, and alveolar macrophage. These models have shown utility in the study of systems medicine. However, no integrated analysis between human tissues has been done. Results To describe tissue-specific functions, Recon 1 was tailored to describe metabolism in three human cells: adipocytes, hepatocytes, and myocytes. These cell-specific networks were manually curated and validated based on known cellular metabolic functions. To study intercellular interactions, a novel multi-tissue type modeling approach was developed to integrate the metabolic functions for the three cell types, and subsequently used to simulate known integrated metabolic cycles. In addition, the multi-tissue model was used to study diabetes: a pathology with systemic properties. High-throughput data was integrated with the network to determine differential metabolic activity between obese and type II obese gastric bypass patients in a whole-body context. Conclusion The multi-tissue type modeling approach presented provides a platform to study integrated metabolic states. As more cell and tissue-specific models are released, it is critical to develop a framework in which to study their interdependencies. PMID:22041191

  7. Plasma levels of human neurotensin: methodological and physiological considerations.

    PubMed

    Ferris, C F; George, J K; Eastwood, G; Potegal, M; Carraway, R E

    1991-01-01

    The ingestion of a meal high in fat content is known to increase circulating levels of neurotensin (NT) in humans. However, the magnitude of the postprandial rise of NT in the general circulation and its physiological significance have been subject of much debate. The present study examines circulating levels of NT in male volunteers prior to and following each of their three daily meals (ca. 31 g fat/meal). The response observed are also compared to that elicited by the direct instillation of intralipid (ca. 44 g fat) into the duodenum. NT levels were determined by radioimmunoassay of acid/acetone extracted plasma fractionated by high pressure liquid chromatography. Meals caused a significant but modest increase in NT levels, with the largest increment (ca. 4 fmol/ml) occurring after breakfast. In contrast, NT levels increased ca. 20 fmol/ml with intraduodenal instillation of lipid. The meal-stimulated increases in circulating NT measured here are 4- to 5-fold less than those reported by others, the difference most likely reflecting the lesser amount of lipid ingested. Previous studies provided subjects with single meals containing in excess of 120 g of fat; the 30 g of fat ingested by our subjects, ca. 33% of total caloric intake, is near that recommended by the U.S. Senate, Select Committee on Nutritional and Human Needs. These data show that diets with a reasonable fat content have only a modest effect on circulating levels of NT. PMID:2067972

  8. Body Dissatisfaction and Mirror Exposure: Evidence for a Dissociation between Self-Report and Physiological Responses in Highly Body-Dissatisfied Women

    PubMed Central

    Servián-Franco, Fátima; Moreno-Domínguez, Silvia; del Paso, Gustavo A. Reyes

    2015-01-01

    Background Weight and shape concerns are widespread in the general population. Mirror exposure has been used to reduce body dissatisfaction but little is known about the mechanisms which underlie this therapeutic technique. The present study examined emotional, cognitive, and psychophysiological responses, in women with high and low levels of body dissatisfaction, exposed to their own bodies in a mirror. Method Forty-two university-attending women (21 high body-dissatisfied (HBD) and 21 low body-dissatisfied (LBD)), were confronted with their own body during four 5-min trials in which participants were instructed to focus their attention on different parts of their body under standardized conditions. Emotional and cognitive measures were taken after each exposure trial. Heart rate (HR) and skin conductance (SC) were recorded continuously. Results HBD women experienced more negative emotions and cognitions following body exposure compared to LBD women but, conversely, showed a reduced physiological reaction in terms of HR and SC. In both groups greater physiological responses were observed looking at the thighs, buttocks, and abdomen. Extent of negative emotions and cognitions were positively associated with HR and/or SC in LBD women but no associations were observed in HBD women. Conclusion The dissociation between self-report and psychophysiological measures in HBD women supports the existence of a passive-behavioral inhibited coping style in HBD women and suggests deficiencies in the generation of physiological correlates of emotion related to body dissatisfaction. PMID:25830861

  9. Trace elements in human physiology and pathology: zinc and metallothioneins.

    PubMed

    Tapiero, Haim; Tew, Kenneth D

    2003-11-01

    Zinc is one of the most abundant nutritionally essential elements in the human body. It is found in all body tissues with 85% of the whole body zinc in muscle and bone, 11% in the skin and the liver and the remaining in all the other tissues. In multicellular organisms, virtually all zinc is intracellular, 30-40% is located in the nucleus, 50% in the cytoplasm, organelles and specialized vesicles (for digestive enzymes or hormone storage) and the remainder in the cell membrane. Zinc intake ranges from 107 to 231 micromol/d depending on the source, and human zinc requirement is estimated at 15 mg/d. Zinc has been shown to be essential to the structure and function of a large number of macromolecules and for over 300 enzymic reactions. It has both catalytic and structural roles in enzymes, while in zinc finger motifs, it provides a scaffold that organizes protein sub-domains for the interaction with either DNA or other proteins. It is critical for the function of a number of metalloproteins, inducing members of oxido-reductase, hydrolase ligase, lyase family and has co-activating functions with copper in superoxide dismutase or phospholipase C. The zinc ion (Zn(++)) does not participate in redox reactions, which makes it a stable ion in a biological medium whose potential is in constant flux. Zinc ions are hydrophilic and do not cross cell membranes by passive diffusion. In general, transport has been described as having both saturable and non-saturable components, depending on the Zn(II) concentrations involved. Zinc ions exist primarily in the form of complexes with proteins and nucleic acids and participate in all aspects of intermediary metabolism, transmission and regulation of the expression of genetic information, storage, synthesis and action of peptide hormones and structural maintenance of chromatin and biomembranes. PMID:14652165

  10. The physiology and pathophysiology of human breath-hold diving.

    PubMed

    Lindholm, Peter; Lundgren, Claes E G

    2009-01-01

    This is a brief overview of physiological reactions, limitations, and pathophysiological mechanisms associated with human breath-hold diving. Breath-hold duration and ability to withstand compression at depth are the two main challenges that have been overcome to an amazing degree as evidenced by the current world records in breath-hold duration at 10:12 min and depth of 214 m. The quest for even further performance enhancements continues among competitive breath-hold divers, even if absolute physiological limits are being approached as indicated by findings of pulmonary edema and alveolar hemorrhage postdive. However, a remarkable, and so far poorly understood, variation in individual disposition for such problems exists. Mortality connected with breath-hold diving is primarily concentrated to less well-trained recreational divers and competitive spearfishermen who fall victim to hypoxia. Particularly vulnerable are probably also individuals with preexisting cardiac problems and possibly, essentially healthy divers who may have suffered severe alternobaric vertigo as a complication to inadequate pressure equilibration of the middle ears. The specific topics discussed include the diving response and its expression by the cardiovascular system, which exhibits hypertension, bradycardia, oxygen conservation, arrhythmias, and contraction of the spleen. The respiratory system is challenged by compression of the lungs with barotrauma of descent, intrapulmonary hemorrhage, edema, and the effects of glossopharyngeal insufflation and exsufflation. Various mechanisms associated with hypoxia and loss of consciousness are discussed, including hyperventilation, ascent blackout, fasting, and excessive postexercise O(2) consumption. The potential for high nitrogen pressure in the lungs to cause decompression sickness and N(2) narcosis is also illuminated. PMID:18974367

  11. Warming reinforces nonconsumptive predator effects on prey growth, physiology, and body stoichiometry.

    PubMed

    Janssens, Lizanne; Van Dievel, Marie; Stoks, Robby

    2015-12-01

    While nonconsumptive effects of predators may strongly affect prey populations, little is known how future warming will modulate these effects. Such information would be especially relevant with regard to prey physiology and resulting changes in prey stoichiometry. We investigated in Enallagma cyathigerum damselfly larvae the effects of a 4°C warming (20°C vs. 24°C) and predation risk on growth rate, physiology and body stoichiometry, for the first time including all key mechanisms suggested by the general stress paradigm (GSP) on how stressors shape changes in body stoichiometry. Growth rate and energy storage were higher at 24°C. Based on thermodynamic principles and the growth rate hypothesis, we could demonstrate predictable reductions in body C:P under warming and link these to the increase in P-rich RNA; the associated warming-induced decrease in C:N may be explained by the increased synthesis of N-rich proteins. Yet, under predation risk, growth rate instead decreased with warming and the warming-induced decreases in C:N and C:P disappeared. As predicted by the GSP, larvae increased body C:N and C:P at 24°C under predation risk. Notably, we did not detect the assumed GSP-mechanisms driving these changes: despite an increased metabolic rate there was neither an increase of C-rich biomolecules (instead fat and sugar contents decreased under predation risk), nor a decrease of N-rich proteins. We hypothesize that the higher C:N and N:P under predation risk are caused by a higher investment in morphological defense. This may also explain the stronger predator-induced increase in C:N under warming. The expected higher C:P under predation risk was only present under warming and matched the observed growth reduction and associated reduction in P-rich RNA. Our integrated mechanistic approach unraveled novel pathways of how warming and predation risk shape body stoichiometry. Key findings that (1) warming effects on elemental stoichiometry were predictable and

  12. Physiological signal based entity authentication for body area sensor networks and mobile healthcare systems.

    PubMed

    Bao, Shu-Di; Zhang, Yuan-Ting; Shen, Lian-Feng

    2005-01-01

    With the evolution of m-Health, an increasing number of biomedical sensors will be worn on or implanted in an individual in the future for the monitoring, diagnosis, and treatment of diseases. For the optimization of resources, it is therefore necessary to investigate how to interconnect these sensors in a wireless body area network, wherein security of private data transmission is always a major concern. This paper proposes a novel solution to tackle the problem of entity authentication in body area sensor network (BASN) for m-Health. Physiological signals detected by biomedical sensors have dual functions: (1) for a specific medical application, and (2) for sensors in the same BASN to recognize each other by biometrics. A feasibility study of proposed entity authentication scheme was carried out on 12 healthy individuals, each with 2 channels of photoplethysmogram (PPG) captured simultaneously at different parts of the body. The beat-to-beat heartbeat interval is used as a biometric characteristic to generate identity of the individual. The results of statistical analysis suggest that it is a possible biometric feature for the entity authentication of BASN. PMID:17282734

  13. An investigative laboratory course in human physiology using computer technology and collaborative writing.

    PubMed

    FitzPatrick, Kathleen A

    2004-12-01

    Active investigative student-directed experiences in laboratory science are being encouraged by national science organizations. A growing body of evidence from classroom assessment supports their effectiveness. This study describes four years of implementation and assessment of an investigative laboratory course in human physiology for 65 second-year students in sports medicine and biology at a small private comprehensive college. The course builds on skills and abilities first introduced in an introductory investigations course and introduces additional higher-level skills and more complex human experimental models. In four multiweek experimental modules, involving neuromuscular, reflex, and cardiovascular physiology, by use of computerized hardware/software with a variety of transducers, students carry out self-designed experiments with human subjects and perform data collection and analysis, collaborative writing, and peer editing. In assessments, including standard course evaluations and the Salgains Web-based evaluation, student responses to this approach are enthusiastic, and gains in their skills and abilities are evident in their comments and in improved performance. PMID:15319194

  14. Facilitated early cortical processing of nude human bodies.

    PubMed

    Alho, Jussi; Salminen, Nelli; Sams, Mikko; Hietanen, Jari K; Nummenmaa, Lauri

    2015-07-01

    Functional brain imaging has identified specialized neural systems supporting human body perception. Responses to nude vs. clothed bodies within this system are amplified. However, it remains unresolved whether nude and clothed bodies are processed by same cerebral networks or whether processing of nude bodies recruits additional affective and arousal processing areas. We recorded simultaneous MEG and EEG while participants viewed photographs of clothed and nude bodies. Global field power revealed a peak ∼145ms after stimulus onset to both clothed and nude bodies, and ∼205ms exclusively to nude bodies. Nude-body-sensitive responses were centered first (100-200ms) in the extrastriate and fusiform body areas, and subsequently (200-300ms) in affective-motivational areas including insula and anterior cingulate cortex. We conclude that visibility of sexual features facilitates early cortical processing of human bodies, the purpose of which is presumably to trigger sexual behavior and ultimately ensure reproduction. PMID:25960070

  15. The Human Body: A Unique Media Experience.

    ERIC Educational Resources Information Center

    Tracy, Sandra D.

    1980-01-01

    The author asserts that the body is the first form of media which should be used with deaf students. Stages of the dance process are considered, including developing body movement, translating language into body movement, coordinating movement with music, and projecting emotional reactions to words through facial expression. (CL)

  16. Mathematical description of human body constitution and fatness.

    PubMed

    Sheikh-Zade, Yu R; Galenko-Yaroshevskii, P A; Cherednik, I L

    2014-02-01

    Using mathematical modeling of human body, we demonstrated logical drawbacks of body mass index (BMI1 = M/H(2); A. Quetelet, 1832) and proposed more precise body mass index (BMI2 = M/H(3)) as well as body constitution index (BCI = (M/H(3))(1/2)) and fatness index (FI = M/HC(2)), where M, H, and C are body weight, height, and wrist circumference of the individual. PMID:24771443

  17. Microwave non-contact imaging of subcutaneous human body tissues.

    PubMed

    Kletsov, Andrey; Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

    2015-10-01

    A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated. PMID:26609415

  18. Microwave non-contact imaging of subcutaneous human body tissues

    PubMed Central

    Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

    2015-01-01

    A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated. PMID:26609415

  19. Physiology of the upper segment, body, and lower segment of the esophagus

    PubMed Central

    Miller, Larry; Clavé, Pere; Farré, Ricard; Lecea, Begoña; Ruggieri, Michael R.; Ouyang, Ann; Regan, Julie; McMahon, Barry P.

    2014-01-01

    The following discussion on the physiology of the esophagus includes commentaries on the function of the muscularis mucosa and submucosa as a mechanical antireflux barrier in the esophagus; the different mechanisms of neurological control in the esophageal striated and smooth muscle; new insights from animal models into the neurotransmitters mediating lower esophageal sphincter (LES) relaxation, peristalsis in the esophageal body (EB), and motility of esophageal smooth muscle; differentiation between in vitro properties of the lower esophageal circular muscle, clasp muscle, and sling fibers; alterations in the relationship between pharyngeal contraction and relaxation of the upper esophageal sphincter (UES) in patients with dysphagia; the mechanical relationships between anterior hyoid movement, the extent of upper esophageal opening, and aspiration; the application of fluoroscopy and manometry with biomechanics to define the stages of UES opening; and nonpharmacological approaches to alter the gastroesophageal junction (GEJ). PMID:24117648

  20. The journey of a drug-carrier in the body: an anatomo-physiological perspective.

    PubMed

    Bertrand, Nicolas; Leroux, Jean-Christophe

    2012-07-20

    Recent advances in chemistry and material sciences have witnessed the emergence of an increasing number of novel and complex nanosized carriers for the delivery of drugs and imaging agents. Nevertheless, this raise in complexity does not necessarily offer more efficient systems. The lack of performance experienced by several colloidal drug carriers during the preclinical and clinical development processes can be explained by inadequate pharmacokinetic/biodistribution profiles and/or unacceptable toxicities. A comprehensive understanding of the body characteristics is necessary to predict and prevent these problems from the early stages of nanomaterial conception. In this manuscript, we review and discuss the anatomical and physiological elements which must be taken into account when designing new carriers for delivery or imaging purposes. This article gives a general overview of the main organs involved in the elimination of nanosized materials and briefly summarizes the knowledge acquired over more than 30 years of research and development in the field of drug targeting. PMID:22001607

  1. Comparative gene expression profile of mouse carotid body and adrenal medulla under physiological hypoxia

    PubMed Central

    Ganfornina, MD; Pérez-García, MT; Gutiérrez, G; Miguel-Velado, E; López-López, JR; Marín, A; Sánchez, D; González, C

    2005-01-01

    The carotid body (CB) is an arterial chemoreceptor, bearing specialized type I cells that respond to hypoxia by closing specific K+ channels and releasing neurotransmitters to activate sensory axons. Despite having detailed information on the electrical and neurochemical changes triggered by hypoxia in CB, the knowledge of the molecular components involved in the signalling cascade of the hypoxic response is fragmentary. This study analyses the mouse CB transcriptional changes in response to low PO2 by hybridization to oligonucleotide microarrays. The transcripts were obtained from whole CBs after mice were exposed to either normoxia (21% O2), or physiological hypoxia (10% O2) for 24 h. The CB transcriptional profiles obtained under these environmental conditions were subtracted from the profile of control non-chemoreceptor adrenal medulla extracted from the same animals. Given the common developmental origin of these two organs, they share many properties but differ specifically in their response to O2. Our analysis revealed 751 probe sets regulated specifically in CB under hypoxia (388 up-regulated and 363 down-regulated). These results were corroborated by assessing the transcriptional changes of selected genes under physiological hypoxia with quantitative RT-PCR. Our microarray experiments revealed a number of CB-expressed genes (e.g. TH, ferritin and triosephosphate isomerase) that were known to change their expression under hypoxia. However, we also found novel genes that consistently changed their expression under physiological hypoxia. Among them, a group of ion channels show specific regulation in CB: the potassium channels Kir6.1 and Kcnn4 are up-regulated, while the modulatory subunit Kcnab1 is down-regulated by low PO2 levels. PMID:15890701

  2. Macro And Microcosmus: Moon Influence On The Human Body

    NASA Astrophysics Data System (ADS)

    Zanchin, Giorgio

    Belief in the action of the macrocosmus, i.e., celestial bodies, on the microcosmus, i.e., on man, goes back to the dawn of human thinking. More specifically, lunar phases have been considered to act on behaviour and on physiological functions. This possible relationship has not only been taken for granted for many centuries in ancient medicine but also investigated in a number of modern published works, mainly on the issues of emergency activity; violent behaviour; car accidents; drug overdose; menses and birth; and mood disorders. Indeed, if the idea that the stars and planets may influence human health and behaviour can be traced so far in the past, it seems that not only the laymen but a high proportion of health professionals continue to hold this credence: recently, in New Orleans a questionnaire sent to 325 people indicated that 140 individuals (43%) held the opinion that lunar phenomena alter personal behaviour. Specifically, it came out that mental health professionals (social workers, clinical psychologists, nurses' aides) held this belief more strongly than other occupational groups (Vance, 1995). A short historical outline of some old beliefs and the results of contemporary research on this fascinating, time-honoured field, will be presented.

  3. Dynamics of food availability, body condition and physiological stress response in breeding Black-legged Kittiwakes

    USGS Publications Warehouse

    Kitaysky, A.S.; Wingfield, J.C.; Piatt, J.F.

    1999-01-01

    1. The seasonal dynamics of body condition (BC), circulating corticosterone levels (baseline, BL) and the adrenocortical response to acute stress (SR) were examined in long-lived Black-legged Kittiwakes, Rissa tridactyla, breeding at Duck (food-poor colony) and Gull (food-rich colony) Islands in lower Cook Inlet, Alaska. It was tested whether the dynamics of corticosterone levels reflect a seasonal change in bird physiological condition due to reproduction and/or variation in foraging conditions. 2. BC declined seasonally, and the decline was more pronounced in birds at the food-poor colony. BL and SR levels of corticosterone rose steadily through the reproductive season, and BL levels were significantly higher in birds on Duck island compared with those on Gull Island. During the egg-laying and chick-rearing stages, birds had lower SR on Duck Island than on Gull Island. 3. The results suggest that, in addition to a seasonal change in bird physiology during reproduction, local ecological factors such as food availability affect circulating levels of corticosterone and adrenal response to acute stress.

  4. Influence of body hair removal on physiological responses during breaststroke swimming.

    PubMed

    Sharp, R L; Costill, D L

    1989-10-01

    Nine male collegiate swimmers (EXP) were studied 8 d before (PRE) and 1 d after (POST) shaving the hair from their arms, legs, and exposed trunk. A control group (CON, N = 4) of their teammates was also tested at these times but did not remove body hair. In PRE and POST, distance per stroke (SL), VO2, heart rate (HR), and post-swim blood lactate concentration (BL) were measured during a 365.8 m breaststroke swim at approximately 90% effort. Subjects also performed a tethered breaststroke swim with retarding forces of 6.27, 7.75, and 9.26 kg. The EXP group experienced a significant (P less than 0.05) reduction in BL (mean +/- SE: 8.48 +/- 0.78 to 6.74 +/- 0.74 mmol.l-1), a decreased VO2 (3.60 +/- 0.15 to 3.27 +/- 0.14 l.min-1), an increase in SL (2.07 +/- 0.08 to 2.31 +/- 0.10 m.stroke-1), and an insignificant (P = 0.08) decline in HR (174 +/- 5 to 168 +/- 4 beats.min-1) during the free swim. The CON group showed no changes in BL, SL, or HR. During the tethered swim, there were no significant PRE-POST differences in VO2, HR, or BL for either group. In a separate group of swimmers (nine who shaved body hair and nine controls), removing body hair significantly reduced the rate of velocity decay during a prone glide after a maximal underwater leg push-off. It is concluded that removing body hair reduces active drag, thereby decreasing the physiological cost of swimming. PMID:2691818

  5. Form and function remixed: developmental physiology in the evolution of vertebrate body plans.

    PubMed

    Newman, Stuart A

    2014-06-01

    The most widely accepted model of evolutionary change, the Modern Evolutionary Synthesis, is based on the gradualism of Darwin and Wallace. They, in turn, developed their ideas in the context of 19th century concepts of how matter, including the tissues of animals and plants, could be reshaped and repatterned. A new physics of condensed, chemically, electrically and mechanically excitable materials formulated in the 20th century was, however, readily taken up by physiologists, who applied it to the understanding of dynamical, external condition-dependent and homeostatic properties of individual organisms. Nerve conduction, vascular and airway dynamics, and propagation of electrical excitations in heart and brain tissue all benefited from theories of biochemical oscillation, fluid dynamics, reaction-diffusion-based pattern instability and allied dissipative processes. When, in the late 20th century, the development of body and organ form was increasingly seen to involve dynamical, frequently non-linear processes similar to those that had become standard in physiology, a strong challenge to the evolutionary synthesis emerged. In particular, large-scale changes in organismal form now had a scientific basis other than gradualistic natural selection based on adaptive advantage. Moreover, heritable morphological changes were seen to be capable of occurring abruptly with little or no genetic change, with involvement of the external environment, and in preferred directions. This paper discusses three examples of morphological motifs of vertebrate bodies and organs, the somites, the skeletons of the paired limbs, and musculoskeletal novelties distinctive to birds, for which evolutionary origination and transformation can be understood on the basis of the physiological and biophysical determinants of their development. PMID:24817211

  6. Form and function remixed: developmental physiology in the evolution of vertebrate body plans

    PubMed Central

    Newman, Stuart A

    2014-01-01

    The most widely accepted model of evolutionary change, the Modern Evolutionary Synthesis, is based on the gradualism of Darwin and Wallace. They, in turn, developed their ideas in the context of 19th century concepts of how matter, including the tissues of animals and plants, could be reshaped and repatterned. A new physics of condensed, chemically, electrically and mechanically excitable materials formulated in the 20th century was, however, readily taken up by physiologists, who applied it to the understanding of dynamical, external condition-dependent and homeostatic properties of individual organisms. Nerve conduction, vascular and airway dynamics, and propagation of electrical excitations in heart and brain tissue all benefited from theories of biochemical oscillation, fluid dynamics, reaction–diffusion-based pattern instability and allied dissipative processes. When, in the late 20th century, the development of body and organ form was increasingly seen to involve dynamical, frequently non-linear processes similar to those that had become standard in physiology, a strong challenge to the evolutionary synthesis emerged. In particular, large-scale changes in organismal form now had a scientific basis other than gradualistic natural selection based on adaptive advantage. Moreover, heritable morphological changes were seen to be capable of occurring abruptly with little or no genetic change, with involvement of the external environment, and in preferred directions. This paper discusses three examples of morphological motifs of vertebrate bodies and organs, the somites, the skeletons of the paired limbs, and musculoskeletal novelties distinctive to birds, for which evolutionary origination and transformation can be understood on the basis of the physiological and biophysical determinants of their development. PMID:24817211

  7. HuPSON: the human physiology simulation ontology

    PubMed Central

    2013-01-01

    Background Large biomedical simulation initiatives, such as the Virtual Physiological Human (VPH), are substantially dependent on controlled vocabularies to facilitate the exchange of information, of data and of models. Hindering these initiatives is a lack of a comprehensive ontology that covers the essential concepts of the simulation domain. Results We propose a first version of a newly constructed ontology, HuPSON, as a basis for shared semantics and interoperability of simulations, of models, of algorithms and of other resources in this domain. The ontology is based on the Basic Formal Ontology, and adheres to the MIREOT principles; the constructed ontology has been evaluated via structural features, competency questions and use case scenarios. The ontology is freely available at: http://www.scai.fraunhofer.de/en/business-research-areas/bioinformatics/downloads.html (owl files) and http://bishop.scai.fraunhofer.de/scaiview/ (browser). Conclusions HuPSON provides a framework for a) annotating simulation experiments, b) retrieving relevant information that are required for modelling, c) enabling interoperability of algorithmic approaches used in biomedical simulation, d) comparing simulation results and e) linking knowledge-based approaches to simulation-based approaches. It is meant to foster a more rapid uptake of semantic technologies in the modelling and simulation domain, with particular focus on the VPH domain. PMID:24267822

  8. Effects of Weightlessness on Human Fluid and Electrolyte Physiology

    NASA Technical Reports Server (NTRS)

    Leach, Carolyn S.; Johnson, Philip C., Jr.

    1991-01-01

    The changes that occur in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. A number of questions remain to be answered. At a time when plasma volume and extracellular fluid volume are contracted and salt and water intake is unrestricted. ADH does not correct the volume deficit and serum sodium decreases. Change in secretion or activity of a natriuretic factor during spaceflight is one possible explanation. Recent identification of a polypeptide hormone produced in cardiac muscle cells which is natiuretic, is hypotensive, and has an inhibitory effect on renin and aldosterone secretion has renewed interest in the role of a natriuretic factor. The role of this atrial natriuretic factor (ANF) in both long- and short-term variation in extracellular volumes and in the inability of the kidney to bring about an escape from the sodium-retaining state accompanying chronic cardiac dysfunction makes it reasonable to look for a role of ANF in the regulation of sodium during exposure to microgravity. Prostaglandin-E is another hormone that may antagonize the action of ADH. Assays of these hormones will be performed on samples from crew members in the future.

  9. Functional Neuroimaging Insights into the Physiology of Human Sleep

    PubMed Central

    Dang-Vu, Thien Thanh; Schabus, Manuel; Desseilles, Martin; Sterpenich, Virginie; Bonjean, Maxime; Maquet, Pierre

    2010-01-01

    -Vu TT; Schabus M; Desseilles M; Sterpenich V; Bonjean M; Maquet P. Functional neuroimaging insights into the physiology of human sleep. SLEEP 2010;33(12):1589-1603. PMID:21120121

  10. Physiological Characterisation of Human iPS-Derived Dopaminergic Neurons

    PubMed Central

    Ribeiro Fernandes, Hugo J.; Vowles, Jane; James, William S.; Cowley, Sally A.; Wade-Martins, Richard

    2014-01-01

    Human induced pluripotent stem cells (hiPSCs) offer the potential to study otherwise inaccessible cell types. Critical to this is the directed differentiation of hiPSCs into functional cell lineages. This is of particular relevance to research into neurological disease, such as Parkinson’s disease (PD), in which midbrain dopaminergic neurons degenerate during disease progression but are unobtainable until post-mortem. Here we report a detailed study into the physiological maturation over time of human dopaminergic neurons in vitro. We first generated and differentiated hiPSC lines into midbrain dopaminergic neurons and performed a comprehensive characterisation to confirm dopaminergic functionality by demonstrating dopamine synthesis, release, and re-uptake. The neuronal cultures include cells positive for both tyrosine hydroxylase (TH) and G protein-activated inward rectifier potassium channel 2 (Kir3.2, henceforth referred to as GIRK2), representative of the A9 population of substantia nigra pars compacta (SNc) neurons vulnerable in PD. We observed for the first time the maturation of the slow autonomous pace-making (<10 Hz) and spontaneous synaptic activity typical of mature SNc dopaminergic neurons using a combination of calcium imaging and electrophysiology. hiPSC-derived neurons exhibited inositol tri-phosphate (IP3) receptor-dependent release of intracellular calcium from the endoplasmic reticulum in neuronal processes as calcium waves propagating from apical and distal dendrites, and in the soma. Finally, neurons were susceptible to the dopamine neuron-specific toxin 1-methyl-4-phenylpyridinium (MPP+) which reduced mitochondrial membrane potential and altered mitochondrial morphology. Mature hiPSC-derived dopaminergic neurons provide a neurophysiologically-defined model of previously inaccessible vulnerable SNc dopaminergic neurons to bridge the gap between clinical PD and animal models. PMID:24586273

  11. Physiological characterisation of human iPS-derived dopaminergic neurons.

    PubMed

    Hartfield, Elizabeth M; Yamasaki-Mann, Michiko; Ribeiro Fernandes, Hugo J; Vowles, Jane; James, William S; Cowley, Sally A; Wade-Martins, Richard

    2014-01-01

    Human induced pluripotent stem cells (hiPSCs) offer the potential to study otherwise inaccessible cell types. Critical to this is the directed differentiation of hiPSCs into functional cell lineages. This is of particular relevance to research into neurological disease, such as Parkinson's disease (PD), in which midbrain dopaminergic neurons degenerate during disease progression but are unobtainable until post-mortem. Here we report a detailed study into the physiological maturation over time of human dopaminergic neurons in vitro. We first generated and differentiated hiPSC lines into midbrain dopaminergic neurons and performed a comprehensive characterisation to confirm dopaminergic functionality by demonstrating dopamine synthesis, release, and re-uptake. The neuronal cultures include cells positive for both tyrosine hydroxylase (TH) and G protein-activated inward rectifier potassium channel 2 (Kir3.2, henceforth referred to as GIRK2), representative of the A9 population of substantia nigra pars compacta (SNc) neurons vulnerable in PD. We observed for the first time the maturation of the slow autonomous pace-making (<10 Hz) and spontaneous synaptic activity typical of mature SNc dopaminergic neurons using a combination of calcium imaging and electrophysiology. hiPSC-derived neurons exhibited inositol tri-phosphate (IP3) receptor-dependent release of intracellular calcium from the endoplasmic reticulum in neuronal processes as calcium waves propagating from apical and distal dendrites, and in the soma. Finally, neurons were susceptible to the dopamine neuron-specific toxin 1-methyl-4-phenylpyridinium (MPP+) which reduced mitochondrial membrane potential and altered mitochondrial morphology. Mature hiPSC-derived dopaminergic neurons provide a neurophysiologically-defined model of previously inaccessible vulnerable SNc dopaminergic neurons to bridge the gap between clinical PD and animal models. PMID:24586273

  12. [The gift of human body's products: philosophical and ethical aspects].

    PubMed

    Baertschi, B

    2014-09-01

    In continental Europe, there is a very strong moral condemnation against putting parts or products of the human body on sale-and, consequently, against putting sperms and oocytes on sale. Only a gift is morally permissible. The situation is different in Anglo-Saxon countries. Who is right? Above all, it must be noticed that two views of the human body are facing each other here: for the first, the human body is a part of the person (so, it partakes of the person's dignity), whereas for the second, the human body is a possession of the person (the person is the owner of his/her body). In my opinion, the argument of dignity comes up against serious objections, and the property argument is more consistent. However, it does not follow that it would be judicious to put parts and products of the human body for sale on a market. PMID:25164164

  13. Using Stimulation of the Diving Reflex in Humans to Teach Integrative Physiology

    ERIC Educational Resources Information Center

    Choate, Julia K.; Denton, Kate M.; Evans, Roger G.; Hodgson, Yvonne

    2014-01-01

    During underwater submersion, the body responds by conserving O[subscript 2] and prioritizing blood flow to the brain and heart. These physiological adjustments, which involve the nervous, cardiovascular, and respiratory systems, are known as the diving response and provide an ideal example of integrative physiology. The diving reflex can be…

  14. Simulation of monoclonal antibody pharmacokinetics in humans using a minimal physiologically based model.

    PubMed

    Li, Linzhong; Gardner, Iain; Dostalek, Miroslav; Jamei, Masoud

    2014-09-01

    Compared to small chemical molecules, monoclonal antibodies and Fc-containing derivatives (mAbs) have unique pharmacokinetic behaviour characterised by relatively poor cellular permeability, minimal renal filtration, binding to FcRn, target-mediated drug disposition, and disposition via lymph. A minimal physiologically based pharmacokinetic (PBPK) model to describe the pharmacokinetics of mAbs in humans was developed. Within the model, the body is divided into three physiological compartments; plasma, a single tissue compartment and lymph. The tissue compartment is further sub-divided into vascular, endothelial and interstitial spaces. The model simultaneously describes the levels of endogenous IgG and exogenous mAbs in each compartment and sub-compartment and, in particular, considers the competition of these two species for FcRn binding in the endothelial space. A Monte-Carlo sampling approach is used to simulate the concentrations of endogenous IgG and mAb in a human population. Existing targeted-mediated drug disposition (TMDD) models are coupled with the minimal PBPK model to provide a general platform for simulating the pharmacokinetics of therapeutic antibodies using primarily pre-clinical data inputs. The feasibility of utilising pre-clinical data to parameterise the model and to simulate the pharmacokinetics of adalimumab and an anti-ALK1 antibody (PF-03446962) in a population of individuals was investigated and results were compared to published clinical data. PMID:25004823

  15. The EuroPhysiome, STEP and a roadmap for the virtual physiological human.

    PubMed

    Fenner, J W; Brook, B; Clapworthy, G; Coveney, P V; Feipel, V; Gregersen, H; Hose, D R; Kohl, P; Lawford, P; McCormack, K M; Pinney, D; Thomas, S R; Van Sint Jan, S; Waters, S; Viceconti, M

    2008-09-13

    Biomedical science and its allied disciplines are entering a new era in which computational methods and technologies are poised to play a prevalent role in supporting collaborative investigation of the human body. Within Europe, this has its focus in the virtual physiological human (VPH), which is an evolving entity that has emerged from the EuroPhysiome initiative and the strategy for the EuroPhysiome (STEP) consortium. The VPH is intended to be a solution to common infrastructure needs for physiome projects across the globe, providing a unifying architecture that facilitates integration and prediction, ultimately creating a framework capable of describing Homo sapiens in silico. The routine reliance of the biomedical industry, biomedical research and clinical practice on information technology (IT) highlights the importance of a tailor-made and robust IT infrastructure, but numerous challenges need to be addressed if the VPH is to become a mature technological reality. Appropriate investment will reap considerable rewards, since it is anticipated that the VPH will influence all sectors of society, with implications predominantly for improved healthcare, improved competitiveness in industry and greater understanding of (patho)physiological processes. This paper considers issues pertinent to the development of the VPH, highlighted by the work of the STEP consortium. PMID:18559316

  16. Development of Preferences for the Human Body Shape in Infancy.

    ERIC Educational Resources Information Center

    Slaughter, Virginia; Heron, Michelle; Sim, Susan

    2002-01-01

    Two studies investigated development of infants' visual preferences for the human body shape. Results indicated that 18-month-olds had a reliable preference for scrambled body shapes over typical body shapes in line drawings, while 12- and 15-month-olds did not respond differentially. In condition using photographs, only 18-month-olds had reliable…

  17. In vivo measurement of human body composition

    NASA Technical Reports Server (NTRS)

    Pace, N.

    1974-01-01

    The time course of physiological changes that occur during the first 21 days of continuous bed rest was examined. The test involved a total of 14 men in the age range of 25 to 36 years. The subjects were divided into groups and tested on a staggered schedule. Results are presented.

  18. Matrix Intensification Affects Body and Physiological Condition of Tropical Forest-Dependent Passerines

    PubMed Central

    Deikumah, Justus P.; McAlpine, Clive A.; Maron, Martine

    2015-01-01

    Matrix land-use intensification is a relatively recent and novel landscape change that can have important influences on the biota within adjacent habitat patches. While there are immediate local changes that it brings about, the influences on individual animals occupying adjacent habitats may be less evident initially. High-intensity land use could induce chronic stress in individuals in nearby remnants, leading ultimately to population declines. We investigated how physiological indicators and body condition measures of tropical forest-dependent birds differ between forest adjacent to surface mining sites and that near farmlands at two distances from remnant edge in southwest Ghana. We used mixed effects models of several condition indices including residual body mass and heterophil to lymphocyte (H/L) ratios (an indicator of elevated chronic stress) to explore the effect of matrix intensity on forest-dependent passerines classed as either sedentary area-sensitive habitat specialists or nomadic generalists. Individual birds occupying tropical forest remnants near surface mining sites were in poorer condition, as indicated by lower residual body mass and elevated chronic stress, compared to those in remnants near agricultural lands. The condition of the sedentary forest habitat specialists white-tailed alethe, Alethe diademata and western olive sunbird, Cyanomitra obscura was most negatively affected by high-intensity surface mining land-use adjacent to remnants, whereas generalist species were not affected. Land use intensification may set in train a new trajectory of faunal relaxation beyond that expected based on habitat loss alone. Patterns of individual condition may be useful in identifying habitats where species population declines may occur before faunal relaxation has concluded. PMID:26107179

  19. Matrix Intensification Affects Body and Physiological Condition of Tropical Forest-Dependent Passerines.

    PubMed

    Deikumah, Justus P; McAlpine, Clive A; Maron, Martine

    2015-01-01

    Matrix land-use intensification is a relatively recent and novel landscape change that can have important influences on the biota within adjacent habitat patches. While there are immediate local changes that it brings about, the influences on individual animals occupying adjacent habitats may be less evident initially. High-intensity land use could induce chronic stress in individuals in nearby remnants, leading ultimately to population declines. We investigated how physiological indicators and body condition measures of tropical forest-dependent birds differ between forest adjacent to surface mining sites and that near farmlands at two distances from remnant edge in southwest Ghana. We used mixed effects models of several condition indices including residual body mass and heterophil to lymphocyte (H/L) ratios (an indicator of elevated chronic stress) to explore the effect of matrix intensity on forest-dependent passerines classed as either sedentary area-sensitive habitat specialists or nomadic generalists. Individual birds occupying tropical forest remnants near surface mining sites were in poorer condition, as indicated by lower residual body mass and elevated chronic stress, compared to those in remnants near agricultural lands. The condition of the sedentary forest habitat specialists white-tailed alethe, Alethe diademata and western olive sunbird, Cyanomitra obscura was most negatively affected by high-intensity surface mining land-use adjacent to remnants, whereas generalist species were not affected. Land use intensification may set in train a new trajectory of faunal relaxation beyond that expected based on habitat loss alone. Patterns of individual condition may be useful in identifying habitats where species population declines may occur before faunal relaxation has concluded. PMID:26107179

  20. Water and electrolytes. [in human bodies

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Harrison, M. H.

    1986-01-01

    It has been found that the performance of the strongest and fittest people will deteriorate rapidly with dehydration. The present paper is concerned with the anatomy of the fluid spaces in the body, taking into account also the fluid shifts and losses during exercise and their effects on performance. Total body water is arbitrarily divided into that contained within cells (cellular) and that located outside the cells (extracellular). The anatomy of body fluid compartments is considered along with the effects of exercise on body water, fluid shifts with exercise, the consequences of sweating, dehydration and exercise, heat acclimatization and endurance training, the adverse effects of dehydration, thirst and drinking during exercise, stimuli for drinking, and water, electrolyte, and carbohydrate replacement during exercise. It is found that the deterioration of physical exercise performance due to dehydration begins when body weight decreases by about 1 percent.

  1. High School Students' Understanding of the Human Body System

    ERIC Educational Resources Information Center

    Assaraf, Orit Ben-Zvi; Dodick, Jeff; Tripto, Jaklin

    2013-01-01

    In this study, 120 tenth-grade students from 8 schools were examined to determine the extent of their ability to perceive the human body as a system after completing the first stage in their biology curriculum--"The human body, emphasizing homeostasis". The students' systems thinking was analyzed according to the STH thinking model, which roughly…

  2. Physiological characterization of human muscle acetylcholine receptors from ALS patients

    PubMed Central

    Palma, Eleonora; Inghilleri, Maurizio; Conti, Luca; Deflorio, Cristina; Frasca, Vittorio; Manteca, Alessia; Pichiorri, Floriana; Roseti, Cristina; Torchia, Gregorio; Limatola, Cristina; Grassi, Francesca; Miledi, Ricardo

    2011-01-01

    Amyotrophic lateral sclerosis (ALS) is characterized by progressive degeneration of motor neurons leading to muscle paralysis. Research in transgenic mice suggests that the muscle actively contributes to the disease onset, but such studies are difficult to pursue in humans and in vitro models would represent a good starting point. In this work we show that tiny amounts of muscle from ALS or from control denervated muscle, obtained by needle biopsy, are amenable to functional characterization by two different technical approaches: “microtransplantation” of muscle membranes into Xenopus oocytes and culture of myogenic satellite cells. Acetylcholine (ACh)-evoked currents and unitary events were characterized in oocytes and multinucleated myotubes. We found that ALS acetylcholine receptors (AChRs) retain their native physiological characteristics, being activated by ACh and nicotine and blocked by α-bungarotoxin (α-BuTX), d-tubocurarine (dTC), and galantamine. The reversal potential of ACh-evoked currents and the unitary channel behavior were also typical of normal muscle AChRs. Interestingly, in oocytes injected with muscle membranes derived from ALS patients, the AChRs showed a significant decrease in ACh affinity, compared with denervated controls. Finally, riluzole, the only drug currently used against ALS, reduced, in a dose-dependent manner, the ACh-evoked currents, indicating that its action remains to be fully characterized. The two methods described here will be important tools for elucidating the role of muscle in ALS pathogenesis and for developing drugs to counter the effects of this disease. PMID:22128328

  3. Human lead metabolism: Chronic exposure, bone lead and physiological models

    NASA Astrophysics Data System (ADS)

    Fleming, David Eric Berkeley

    Exposure to lead is associated with a variety of detrimental health effects. After ingestion or inhalation, lead may be taken up from the bloodstream and retained by bone tissue. X-ray fluorescence was used to make in vivo measurements of bone lead concentration at the tibia and calcaneus for 367 active and 14 retired lead smelter workers. Blood lead levels following a labour disruption were used in conjunction with bone lead readings to examine the endogenous release of lead from bone. Relations between bone lead and a cumulative blood lead index differed depending on time of hiring. This suggests that the transfer of lead from blood to bone has changed over time, possibly as a result of varying exposure conditions. A common polymorphism in the δ-aminolevulinate dehydratase (ALAD) enzyme may influence the distribution of lead in humans. Blood lead levels were higher for smelter workers expressing the more rare ALAD2 allele. Bone lead concentrations, however, were not significantly different. This implies that a smaller proportion of lead in blood is distributed to tissue for individuals expressing the ALAD2 allele. The O'Flaherty physiological model of lead metabolism was modified slightly and tested with input from the personal exposure histories of smelter workers. The model results were consistent with observation in tern of endogenous exposure to lead and accumulation of lead in cortical bone. Modelling the calcaneus as a trabecular bone site did not reproduce observed trends. variations in lead metabolism between different trabecular sites may therefore be significant. The model does not incorporate a genetic component, and its output did not reflect observed differences in this respect. This result provides further support for the influence of the ALAD polymorphism on lead metabolism. Experimental trials with a digital spectrometer revealed superior energy resolution and count throughput relative to the conventional X-ray fluorescence system. The associated

  4. Human Identification at a Distance Using Body Shape Information

    NASA Astrophysics Data System (ADS)

    Rashid, N. K. A. M.; Yahya, M. F.; Shafie, A. A.

    2013-12-01

    Shape of human body is unique from one person to another. This paper presents an intelligent system approach for human identification at a distance using human body shape information. The body features used are the head, shoulder, and trunk. Image processing techniques for detection of these body features were developed in this work. Then, the features are recognized using fuzzy logic approach and used as inputs to a recognition system based on a multilayer neural network. The developed system is only applicable for recognizing a person from its frontal view and specifically constrained to male gender to simplify the algorithm. In this research, the accuracy for human identification using the proposed method is 77.5%. Thus, it is proved that human can be identified at a distance using body shape information.

  5. The physiological relevance of the intestinal microbiota--contributions to human health.

    PubMed

    Tappenden, Kelly A; Deutsch, Andrew S

    2007-12-01

    The intestinal commensal microbiota is a dynamic mixture of essential microbes that develops under key influences of genetics, environment, diet and disease. Population profiles differ along the gastrointestinal tract, from the lumen to the mucosa, and among individuals. The total microbiota population outnumbers the cells in the human body and accounts for 35-50% of the volume of the colonic content. Key physiological functions of the commensal microbiota include protective effects exerted directly by specific bacterial species, control of epithelial cell proliferation and differentiation, production of essential mucosal nutrients, such as short-chain fatty acids and amino acids, prevention of overgrowth of pathogenic organisms, and stimulation of intestinal immunity. Oral probiotics are living microorganisms that upon ingestion in specific numbers exert health benefits beyond those of inherent basic nutrition. Emerging evidence indicates prophylactic and therapeutic utility for probiotic consumption in gastrointestinal health and disease. PMID:18187433

  6. Human physiological adaptation to extended Space Flight and its implications for Space Station

    NASA Technical Reports Server (NTRS)

    Kutyna, F. A.; Shumate, W. H.

    1985-01-01

    Current work evaluating short-term space flight physiological data on the homeostatic changes due to weightlessness is presented as a means of anticipating Space Station long-term effects. An integrated systems analysis of current data shows a vestibulo-sensory adaptation within days; a loss of body mass, fluids, and electrolytes, stabilizing in a month; and a loss in red cell mass over a month. But bone demineralization which did not level off is seen as the biggest concern. Computer algorithms have been developed to simulate the human adaptation to weightlessness. So far these paradigms have been backed up by flight data and it is hoped that they will provide valuable information for future Space Station design. A series of explanatory schematics is attached.

  7. Imaging the Human Body: Micro- and Nanostructure of Human Tissues

    NASA Astrophysics Data System (ADS)

    Schulz, Georg; Deyhle, Hans; Müller, Bert

    Computed tomography based on X-rays is known to provide the best spatial resolution of all clinical three-dimensional imaging facilities and currently reaches a fraction of a millimeter. Better spatial and density resolution is obtained by means of micro computed tomography well established in the field of materials science. It is also very supportive imaging human tissues down to the level of individual cells (Lareida et al. J. Microsc. 234:95, 2009). The article demonstrates the power of micro computed tomography for imaging parts of the human body such as teeth, inner ear, cerebellum, tumors, and urethral tissue with conventional X-ray sources and synchrotron radiation facilities in absorption and phase contrast modes. The second part of the chapter relies on scanning X-ray scattering of tooth slices (Müller et al. Eur. J. Clin. Nanomed. 3:30, 2010) to uncover the presence of nanostructures including their anisotropy and orientation. This imaging technique gives unrivalled insights for medical experts, which will have a major influence on fields such as dental and incontinence treatments.

  8. Differences in the thermal physiology of adult Yarrow's spiny lizards (Sceloporus jarrovii) in relation to sex and body size

    PubMed Central

    Beal, Martin S; Lattanzio, Matthew S; Miles, Donald B

    2014-01-01

    Sexual size dimorphism (SSD) is often assumed to reflect the phenotypic consequences of differential selection operating on each sex. Species that exhibit SSD may also show intersexual differences in other traits, including field-active body temperatures, preferred temperatures, and locomotor performance. For these traits, differences may be correlated with differences in body size or reflect sex-specific trait optima. Male and female Yarrow's spiny lizards, Sceloporus jarrovii, in a population in southeastern Arizona exhibit a difference in body temperature that is unrelated to variation in body size. The observed sexual variation in body temperature may reflect divergence in thermal physiology between the sexes. To test this hypothesis, we measured the preferred body temperatures of male and female lizards when recently fed and fasted. We also estimated the thermal sensitivity of stamina at seven body temperatures. Variation in these traits provided an opportunity to determine whether body size or sex-specific variation unrelated to size shaped their thermal physiology. Female lizards, but not males, preferred a lower body temperature when fasted, and this pattern was unrelated to body size. Larger individuals exhibited greater stamina, but we detected no significant effect of sex on the shape or height of the thermal performance curves. The thermal preference of males and females in a thermal gradient exceeded the optimal temperature for performance in both sexes. Our findings suggest that differences in thermal physiology are both sex- and size-based and that peak performance at low body temperatures may be adaptive given the reproductive cycles of this viviparous species. We consider the implications of our findings for the persistence of S. jarrovii and other montane ectotherms in the face of climate warming. PMID:25540684

  9. Human-on-a-chip design strategies and principles for physiologically based pharmacokinetics/pharmacodynamics modeling.

    PubMed

    Abaci, Hasan Erbil; Shuler, Michael L

    2015-04-01

    Advances in maintaining multiple human tissues on microfluidic platforms has led to a growing interest in the development of microphysiological systems for drug development studies. Determination of the proper design principles and scaling rules for body-on-a-chip systems is critical for their strategic incorporation into physiologically based pharmacokinetic (PBPK)/pharmacodynamic (PD) model-aided drug development. While the need for a functional design considering organ-organ interactions has been considered, robust design criteria and steps to build such systems have not yet been defined mathematically. In this paper, we first discuss strategies for incorporating body-on-a-chip technology into the current PBPK modeling-based drug discovery to provide a conceptual model. We propose two types of platforms that can be involved in the different stages of PBPK modeling and drug development; these are μOrgans-on-a-chip and μHuman-on-a-chip. Then we establish the design principles for both types of systems and develop parametric design equations that can be used to determine dimensions and operating conditions. In addition, we discuss the availability of the critical parameters required to satisfy the design criteria, consider possible limitations for estimating such parameter values and propose strategies to address such limitations. This paper is intended to be a useful guide to the researchers focused on the design of microphysiological platforms for PBPK/PD based drug discovery. PMID:25739725

  10. Possible range of dioxin concentration in human tissues: simulation with a physiologically based model.

    PubMed

    Maruyama, Wakae; Yoshida, Kikuo; Tanaka, Takayuki; Nakanishi, Junko

    2002-12-27

    In risk evaluation of dioxins, monitoring chemical concentrations in human tissues is an important step, and these concentration data can be utilized along with animal toxicity data for extrapolation of human manifestation. However large differences in dioxin concentrations usually exist even among individuals who have never been accidentally exposed to high quantities of dioxin, and this may cause problems in risk analysis. Body size, age, and history of food consumption are factors responsible for these interindividual differences in addition to exposure levels. Using a physiologically based pharmacokinetic (PBPK) model, the influence of differences in body weight, gastrointestinal absorption, and half-life and intake of dioxin were examined on tissue chemical concentration. Dioxin concentrations over a 40-yr time course in human liver, kidneys, fat, blood, muscle and richly perfused tissue were simulated for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (CoPCBs). Model parameters such as tissue-blood partition coefficients for CoPCBs were prepared, and sensitivity analysis was also performed on these parameters. The range of tissue concentrations was approximately 0.17 to 4.1 times the standard concentration, which was calculated using standard model parameters. The simulated ranges included more than 80% of the individual anatomical data for 2,3,7,8-tetrachlorodibenzo-p-dioxin, 1,2,3,7,-pentachlorodibenzo-p-dioxin, and 3,3',4,4',5-pentachlorobiphenyl in liver, fat, and blood. These results suggest that differences in body weight, gastrointestinal absorption, and food intake behavior may partially explain variation in tissue concentrations among individuals, and the possible interindividual uncertainty, which is approximately 24 for the general Japanese population. PMID:12515586

  11. A Human Life-Stage Physiologically Based Pharmacokinetic and Pharmacodynamic Model for Chlorpyrifos: Development and Validation

    SciTech Connect

    Smith, Jordan N.; Hinderliter, Paul M.; Timchalk, Charles; Bartels, M. J.; Poet, Torka S.

    2014-08-01

    Sensitivity to chemicals in animals and humans are known to vary with age. Age-related changes in sensitivity to chlorpyrifos have been reported in animal models. A life-stage physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) model was developed to computationally predict disposition of CPF and its metabolites, chlorpyrifos-oxon (the ultimate toxicant) and 3,5,6-trichloro-2-pyridinol (TCPy), as well as B-esterase inhibition by chlorpyrifos-oxon in humans. In this model, age-dependent body weight was calculated from a generalized Gompertz function, and compartments (liver, brain, fat, blood, diaphragm, rapid, and slow) were scaled based on body weight from polynomial functions on a fractional body weight basis. Blood flows among compartments were calculated as a constant flow per compartment volume. The life-stage PBPK/PD model was calibrated and tested against controlled adult human exposure studies. Model simulations suggest age-dependent pharmacokinetics and response may exist. At oral doses ≥ 0.55 mg/kg of chlorpyrifos (significantly higher than environmental exposure levels), 6 mo old children are predicted to have higher levels of chlorpyrifos-oxon in blood and higher levels of red blood cell cholinesterase inhibition compared to adults from equivalent oral doses of chlorpyrifos. At lower doses that are more relevant to environmental exposures, the model predicts that adults will have slightly higher levels of chlorpyrifos-oxon in blood and greater cholinesterase inhibition. This model provides a computational framework for age-comparative simulations that can be utilized to predict CPF disposition and biological response over various postnatal life-stages.

  12. Molecular clocks and the human condition: approaching their characterization in human physiology and disease.

    PubMed

    Fitzgerald, G A; Yang, G; Paschos, G K; Liang, X; Skarke, C

    2015-09-01

    Molecular clockworks knit together diverse biological networks and compelling evidence from model systems infers their importance in metabolism, immunological and cardiovascular function. Despite this and the diurnal variation in many aspects of human physiology and the phenotypic expression of disease, our understanding of the role and importance of clock function and dysfunction in humans is modest. There are tantalizing hints of connection across the translational divide and some correlative evidence of gene variation and human disease but most of what we know derives from forced desynchrony protocols in controlled environments. We now have the ability to monitor quantitatively ex vivo or in vivo the genome, metabolome, proteome and microbiome of humans in the wild. Combining this capability, with the power of mobile telephony and the evolution of remote sensing, affords a new opportunity for deep phenotyping, including the characterization of diurnal behaviour and the assessment of the impact of the clock on approved drug function. PMID:26332979

  13. Bodily illusions in health and disease: physiological and clinical perspectives and the concept of a cortical 'body matrix'.

    PubMed

    Moseley, G Lorimer; Gallace, Alberto; Spence, Charles

    2012-01-01

    Illusions that induce a feeling of ownership over an artificial body or body-part have been used to explore the complex relationships that exist between the brain's representation of the body and the integrity of the body itself. Here we discuss recent findings in both healthy volunteers and clinical populations that highlight the robust relationship that exists between a person's sense of ownership over a body part, cortical processing of tactile input from that body part, and its physiological regulation. We propose that a network of multisensory and homeostatic brain areas may be responsible for maintaining a 'body-matrix'. That is, a dynamic neural representation that not only extends beyond the body surface to integrate both somatotopic and peripersonal sensory data, but also integrates body-centred spatial sensory data. The existence of such a 'body-matrix' allows our brain to adapt to even profound anatomical and configurational changes to our body. It also plays an important role in maintaining homeostatic control over the body. Its alteration can be seen to have both deleterious and beneficial effects in various clinical populations. PMID:21477616

  14. The Emotional and Attentional Impact of Exposure to One's Own Body in Bulimia Nervosa: A Physiological View

    PubMed Central

    Ortega-Roldán, Blanca; Rodríguez-Ruiz, Sonia; Perakakis, Pandelis; Fernández-Santaella, M. Carmen; Vila, Jaime

    2014-01-01

    Background Body dissatisfaction is the most relevant body image disturbance in bulimia nervosa (BN). Research has shown that viewing one's own body evokes negative thoughts and emotions in individuals with BN. However, the psychophysiological mechanisms involved in this negative reaction have not yet been clearly established. Our aim was to examine the emotional and attentional processes that are activated when patients with BN view their own bodies. Method We examined the effects of viewing a video of one's own body on the physiological (eye-blink startle, cardiac defense, and skin conductance) and subjective (pleasure, arousal, and control ratings) responses elicited by a burst of 110 dB white noise of 500 ms duration. The participants were 30 women with BN and 30 healthy control women. The experimental task consisted of two consecutive and counterbalanced presentations of the auditory stimulus preceded, alternatively, by a video of the participant's own body versus no such video. Results The results showed that, when viewing their own bodies, women with BN experienced (a) greater inhibition of the startle reflex, (b) greater cardiac acceleration in the first component of the defense reaction, (c) greater skin conductance response, and (d) less subjective pleasure and control combined with greater arousal, compared with the control participants. Conclusion Our findings suggest that, for women with BN, peripheral-physiological responses to self-images are dominated by attentional processes, which provoke an immobility reaction caused by a dysfunctional negative response to their own body. PMID:25036222

  15. Whole body vibration at different exposure frequencies: infrared thermography and physiological effects.

    PubMed

    Sonza, Anelise; Robinson, Caroline C; Achaval, Matilde; Zaro, Milton A

    2015-01-01

    The aim of this study was to investigate the effects of whole body vibration (WBV) on physiological parameters, cutaneous temperature, tactile sensitivity, and balance. Twenty-four healthy adults (25.3 ± 2.6 years) participated in four WBV sessions. They spent 15 minutes on a vibration platform in the vertical mode at four different frequencies (31, 35, 40, and 44 Hz) with 1 mm of amplitude. All variables were measured before and after WBV exposure. Pressure sensation in five anatomical regions and both feet was determined using Von Frey monofilaments. Postural sway was measured using a force plate. Cutaneous temperature was obtained with an infrared camera. WBV influences the discharge of the skin touch-pressure receptors, decreasing sensitivity at all measured frequencies and foot regions (P ≤ 0.05). Regarding balance, no differences were found after 20 minutes of WBV at frequencies of 31 and 35 Hz. At 40 and 44 Hz, participants showed higher anterior-posterior center of pressure (COP) velocity and length. The cutaneous temperature of the lower limbs decreased during and 10 minutes after WBV. WBV decreases touch-pressure sensitivity at all measured frequencies 10 min after exposure. This may be related to the impaired balance at higher frequencies since these variables have a role in maintaining postural stability. Vasoconstriction might explain the decreased lower limb temperature. PMID:25664338

  16. Whole Body Vibration at Different Exposure Frequencies: Infrared Thermography and Physiological Effects

    PubMed Central

    Sonza, Anelise; Robinson, Caroline C.; Achaval, Matilde; Zaro, Milton A.

    2015-01-01

    The aim of this study was to investigate the effects of whole body vibration (WBV) on physiological parameters, cutaneous temperature, tactile sensitivity, and balance. Twenty-four healthy adults (25.3 ± 2.6 years) participated in four WBV sessions. They spent 15 minutes on a vibration platform in the vertical mode at four different frequencies (31, 35, 40, and 44 Hz) with 1 mm of amplitude. All variables were measured before and after WBV exposure. Pressure sensation in five anatomical regions and both feet was determined using Von Frey monofilaments. Postural sway was measured using a force plate. Cutaneous temperature was obtained with an infrared camera. WBV influences the discharge of the skin touch-pressure receptors, decreasing sensitivity at all measured frequencies and foot regions (P ≤ 0.05). Regarding balance, no differences were found after 20 minutes of WBV at frequencies of 31 and 35 Hz. At 40 and 44 Hz, participants showed higher anterior-posterior center of pressure (COP) velocity and length. The cutaneous temperature of the lower limbs decreased during and 10 minutes after WBV. WBV decreases touch-pressure sensitivity at all measured frequencies 10 min after exposure. This may be related to the impaired balance at higher frequencies since these variables have a role in maintaining postural stability. Vasoconstriction might explain the decreased lower limb temperature. PMID:25664338

  17. Coherence Between Emotional Experience and Physiology: Does Body Awareness Training Have an Impact?

    PubMed Central

    Sze, Jocelyn A.; Gyurak, Anett; Yuan, Joyce W.; Levenson, Robert W.

    2014-01-01

    Two fundamental issues in emotion theory and research concern: (a) the role of emotion in promoting response coherence across different emotion systems; and (b) the role of awareness of bodily sensations in the experience of emotion. The present study poses a question bridging the two domains; namely, whether training in Vipassana meditation or dance, both of which promote attention to certain kinds of bodily sensations, is associated with greater coherence between the subjective and physiological aspects of emotion. We used lag correlations to examine second-by-second coherence between subjective emotional experience and heart period within individuals across four different films. Participants were either: (a) experienced Vipassana meditators (attention to visceral sensations), (b) experienced dancers (attention to somatic sensations), and (c) controls with no meditation or dance experience. Results indicated a linear relationship in coherence, with meditators having highest levels, dancers having intermediary levels, and controls having lowest levels. We conclude that the coherence between subjective and cardiac aspects of emotion is greater in those who have specialized training that promotes greater body awareness. PMID:21058842

  18. Coherence between emotional experience and physiology: does body awareness training have an impact?

    PubMed

    Sze, Jocelyn A; Gyurak, Anett; Yuan, Joyce W; Levenson, Robert W

    2010-12-01

    Two fundamental issues in emotion theory and research concern: (a) the role of emotion in promoting response coherence across different emotion systems; and (b) the role of awareness of bodily sensations in the experience of emotion. The present study poses a question bridging the two domains; namely, whether training in Vipassana meditation or dance, both of which promote attention to certain kinds of bodily sensations, is associated with greater coherence between the subjective and physiological aspects of emotion. We used lag correlations to examine second-by-second coherence between subjective emotional experience and heart period within individuals across four different films. Participants were either: (a) experienced Vipassana meditators (attention to visceral sensations), (b) experienced dancers (attention to somatic sensations), and (c) controls with no meditation or dance experience. Results indicated a linear relationship in coherence, with meditators having highest levels, dancers having intermediary levels, and controls having lowest levels. We conclude that the coherence between subjective and cardiac aspects of emotion is greater in those who have specialized training that promotes greater body awareness. PMID:21058842

  19. Moving human full body and body parts detection, tracking, and applications on human activity estimation, walking pattern and face recognition

    NASA Astrophysics Data System (ADS)

    Chen, Hai-Wen; McGurr, Mike

    2016-05-01

    We have developed a new way for detection and tracking of human full-body and body-parts with color (intensity) patch morphological segmentation and adaptive thresholding for security surveillance cameras. An adaptive threshold scheme has been developed for dealing with body size changes, illumination condition changes, and cross camera parameter changes. Tests with the PETS 2009 and 2014 datasets show that we can obtain high probability of detection and low probability of false alarm for full-body. Test results indicate that our human full-body detection method can considerably outperform the current state-of-the-art methods in both detection performance and computational complexity. Furthermore, in this paper, we have developed several methods using color features for detection and tracking of human body-parts (arms, legs, torso, and head, etc.). For example, we have developed a human skin color sub-patch segmentation algorithm by first conducting a RGB to YIQ transformation and then applying a Subtractive I/Q image Fusion with morphological operations. With this method, we can reliably detect and track human skin color related body-parts such as face, neck, arms, and legs. Reliable body-parts (e.g. head) detection allows us to continuously track the individual person even in the case that multiple closely spaced persons are merged. Accordingly, we have developed a new algorithm to split a merged detection blob back to individual detections based on the detected head positions. Detected body-parts also allow us to extract important local constellation features of the body-parts positions and angles related to the full-body. These features are useful for human walking gait pattern recognition and human pose (e.g. standing or falling down) estimation for potential abnormal behavior and accidental event detection, as evidenced with our experimental tests. Furthermore, based on the reliable head (face) tacking, we have applied a super-resolution algorithm to enhance

  20. Strategies for improving the physiological relevance of human engineered tissues

    PubMed Central

    Abbott, Rosalyn D; Kaplan, David L

    2015-01-01

    This review examines important robust methods for sustained, steady state, in vitro culture. To achieve ‘physiologically relevant’ tissues in vitro additional complexity must be introduced to provide suitable transport, cell signaling, and matrix support for cells in 3D environments to achieve stable readouts of tissue function. Most tissue engineering systems draw conclusions on tissue functions such as responses to toxins, nutrition or drugs based on short term outcomes with in vitro cultures (2–14 days). However, short term cultures limit insight with physiological relevance, as the cells and tissues have not reached a steady state. PMID:25937289

  1. 3D measurement of human upper body for gesture recognition

    NASA Astrophysics Data System (ADS)

    Wan, Khairunizam; Sawada, Hideyuki

    2007-10-01

    Measurement of human motion is widely required for various applications, and a significant part of this task is to identify motion in the process of human motion recognition. There are several application purposes of doing this research such as in surveillance, entertainment, medical treatment and traffic applications as user interfaces that require the recognition of different parts of human body to identify an action or a motion. The most challenging task in human motion recognition is to achieve the ability and reliability of a motion capture system for tracking and recognizing dynamic movements, because human body structure has many degrees of freedom. Many attempts for recognizing body actions have been reported so far, in which gestural motions have to be measured by some sensors first, and the obtained data are processed in a computer. This paper introduces the 3D motion analysis of human upper body using an optical motion capture system for the purpose of gesture recognition. In this study, the image processing technique to track optical markers attached at feature points of human body is introduced for constructing a human upper body model and estimating its three dimensional motion.

  2. Study of electrical properties of meridian on human body surface

    NASA Astrophysics Data System (ADS)

    Wang, Feng; Uematsu, Haruyuki; Otani, Nobuo

    2007-12-01

    This paper presents the study of the subcutaneous electrical impedance on the human body surface. Measurements of the electrical impedance on five adult male subjects were carried out and analyzed for the possible detection of the acupuncture meridian lines of ancient Chinese medicine on the human body. The distribution of electrical impedance measured at 40 points over the volar side of the right upper limb of the subjects. The results show that electrical impedance varies at different locations of the human body surface, and the locations with lower electrical impedance coincide with the locations where the meridian is believed to exist.

  3. Review of the physiology of human thermal comfort while exercising in urban landscapes and implications for bioclimatic design

    NASA Astrophysics Data System (ADS)

    Vanos, Jennifer K.; Warland, Jon S.; Gillespie, Terry J.; Kenny, Natasha A.

    2010-07-01

    This review comprehensively examines scientific literature pertaining to human physiology during exercise, including mechanisms of heat formation and dissipation, heat stress on the body, the importance of skin temperature monitoring, the effects of clothing, and microclimatic measurements. This provides a critical foundation for microclimatologists and biometeorologists in the understanding of experiments involving human physiology. The importance of the psychological aspects of how an individual perceives an outdoor environment are also reviewed, emphasizing many factors that can indirectly affect thermal comfort (TC). Past and current efforts to develop accurate human comfort models are described, as well as how these models can be used to develop resilient and comfortable outdoor spaces for physical activity. Lack of suitable spaces plays a large role in the deterioration of human health due to physical inactivity, leading to higher rates of illness, heart disease, obesity and heat-related casualties. This trend will continue if urban designers do not make use of current knowledge of bioclimatic urban design, which must be synthesized with physiology, psychology and microclimatology. Increased research is required for furthering our knowledge on the outdoor human energy balance concept and bioclimatic design for health and well-being in urban areas.

  4. Sensing human physiological response using wearable carbon nanotube-based fabrics

    NASA Astrophysics Data System (ADS)

    Wang, Long; Loh, Kenneth J.; Koo, Helen S.

    2016-04-01

    Flexible and wearable sensors for human monitoring have received increased attention. Besides detecting motion and physical activity, measuring human vital signals (e.g., respiration rate and body temperature) provide rich data for assessing subjects' physiological or psychological condition. Instead of using conventional, bulky, sensing transducers, the objective of this study was to design and test a wearable, fabric-like sensing system. In particular, multi-walled carbon nanotube (MWCNT)-latex thin films of different MWCNT concentrations were first fabricated using spray coating. Freestanding MWCNT-latex films were then sandwiched between two layers of flexible fabric using iron-on adhesive to form the wearable sensor. Second, to characterize its strain sensing properties, the fabric sensors were subjected to uniaxial and cyclic tensile load tests, and they exhibited relatively stable electromechanical responses. Finally, the wearable sensors were placed on a human subject for monitoring simple motions and for validating their practical strain sensing performance. Overall, the wearable fabric sensor design exhibited advances such as flexibility, ease of fabrication, light weight, low cost, noninvasiveness, and user comfort.

  5. Human insulin dynamics in women: a physiologically based model.

    PubMed

    Weiss, Michael; Tura, Andrea; Kautzky-Willer, Alexandra; Pacini, Giovanni; D'Argenio, David Z

    2016-02-01

    Currently available models of insulin dynamics are mostly based on the classical compartmental structure and, thus, their physiological utility is limited. In this work, we describe the development of a physiologically based model and its application to data from 154 patients who underwent an insulin-modified intravenous glucose tolerance test (IM-IVGTT). To determine the time profile of endogenous insulin delivery without using C-peptide data and to evaluate the transcapillary transport of insulin, the hepatosplanchnic, renal, and peripheral beds were incorporated into the circulatory model as separate subsystems. Physiologically reasonable population mean estimates were obtained for all estimated model parameters, including plasma volume, interstitial volume of the peripheral circulation (mainly skeletal muscle), uptake clearance into the interstitial space, hepatic and renal clearance, as well as total insulin delivery into plasma. The results indicate that, at a population level, the proposed physiologically based model provides a useful description of insulin disposition, which allows for the assessment of muscle insulin uptake. PMID:26608654

  6. Effects of manufactured nanomaterials on fishes: a target organ and body systems physiology approach.

    PubMed

    Handy, R D; Al-Bairuty, G; Al-Jubory, A; Ramsden, C S; Boyle, D; Shaw, B J; Henry, T B

    2011-10-01

    Manufactured nanomaterials (NM) are already used in consumer products and exposure modelling predicts releases of ng to low µg l(-1) levels of NMs into surface waters. The exposure of aquatic ecosystems, and therefore fishes, to manufactured NMs is inevitable. This review uses a physiological approach to describe the known effects of NMs on the body systems of fishes and to identify the internal target organs, as well as outline aspects of colloid chemistry relevant to fish biology. The acute toxicity data, suggest that the lethal concentration for many NMs is in the mg l(-1) range, and a number of sublethal effects have been reported at concentrations from c. 100 µg to 1 mg l(-1). Exposure to NMs in the water column can cause respiratory toxicity involving altered ventilation, mucus secretion and gill pathology. This may not lead, however, to overt haematological disturbances in the short term. The internal target organs include the liver, spleen and haematopoietic system, kidney, gut and brain; with toxic effects involving oxidative stress, ionoregulatory disturbances and organ pathologies. Some pathology appears to be novel for NMs, such as vascular injury in the brain of rainbow trout Oncorhynchus mykiss with carbon nanotubes. A lack of analytical methods, however, has prevented the reporting of NM concentrations in fish tissues, and the precise uptake mechanisms across the gill or gut are yet to be elucidated. The few dietary exposure studies conducted show no effects on growth or food intake at 10-100 mg kg(-1) inclusions of NMs in the diet of O. mykiss, but there are biochemical disturbances. Early life stages are sensitive to NMs with reports of lethal toxicity and developmental defects. There are many data gaps, however, including how water quality alters physiological responses, effects on immunity and chronic exposure data at environmentally relevant concentrations. Overall, the data so far suggest that the manufactured NMs are not as toxic as some

  7. In vivo measurement of human body composition

    NASA Technical Reports Server (NTRS)

    Pace, N.; Grunbaum, B. W.; Kodama, A. M.; Price, D. C.

    1974-01-01

    The female bed rest study has shown that, the response of women to prolonged recumbency of 2 to 3 weeks duration is very similar to that displayed by men. Some of the key findings in the women after 17 days of continuous recumbency are: (1) a decrease in plasma volume of 12-13 per cent; (2) a small decrease in total body water; (3) a decrease in total body potassium of 3 to 4 per cent; (4) a decrease in plasma potassium concentration of 4 to 5 per cent; (5) a decrease in total circulating plasma protein of 11 to 12 per cent; (6) a decrease in urinary norepinephrine excretion rate of 27 to 28 per cent; (7) a possible increase in urinary magnesium, calcium, and phosphate excretion rates; and (8) a possible increase in urinary citrate excretion rate.

  8. Standoff Human Identification Using Body Shape

    SciTech Connect

    Matzner, Shari; Heredia-Langner, Alejandro; Amidan, Brett G.; Boettcher, Evelyn J.; Lochtefeld, Darrell; Webb, Timothy

    2015-09-01

    The ability to identify individuals is a key component of maintaining safety and security in public spaces and around critical infrastructure. Monitoring an open space is challenging because individuals must be identified and re-identified from a standoff distance nonintrusively, making methods like fingerprinting and even facial recognition impractical. We propose using body shape features as a means for identification from standoff sensing, either complementing other identifiers or as an alternative. An important challenge in monitoring open spaces is reconstructing identifying features when only a partial observation is available, because of the view-angle limitations and occlusion or subject pose changes. To address this challenge, we investigated the minimum number of features required for a high probability of correct identification, and we developed models for predicting a key body feature—height—from a limited set of observed features. We found that any set of nine randomly selected body measurements was sufficient to correctly identify an individual in a dataset of 4426 subjects. For predicting height, anthropometric measures were investigated for correlation with height. Their correlation coefficients and associated linear models were reported. These results—a sufficient number of features for identification and height prediction from a single feature—contribute to developing systems for standoff identification when views of a subject are limited.

  9. The role of VEGF pathways in human physiologic and pathologic angiogenesis.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In pre-clinical models VEGF is a potent stimulant of both physiologic and pathologic angiogenesis. Conversely, anti-VEGF regimens have successfully inhibited angiogenesis both in vitro and in vivo. We hypothesized that VEGF would stimulate both physiologic and pathologic angiogenesis in a human-ba...

  10. Dynamic Human Body Modeling Using a Single RGB Camera

    PubMed Central

    Zhu, Haiyu; Yu, Yao; Zhou, Yu; Du, Sidan

    2016-01-01

    In this paper, we present a novel automatic pipeline to build personalized parametric models of dynamic people using a single RGB camera. Compared to previous approaches that use monocular RGB images, our system can model a 3D human body automatically and incrementally, taking advantage of human motion. Based on coarse 2D and 3D poses estimated from image sequences, we first perform a kinematic classification of human body parts to refine the poses and obtain reconstructed body parts. Next, a personalized parametric human model is generated by driving a general template to fit the body parts and calculating the non-rigid deformation. Experimental results show that our shape estimation method achieves comparable accuracy with reconstructed models using depth cameras, yet requires neither user interaction nor any dedicated devices, leading to the feasibility of using this method on widely available smart phones. PMID:26999159

  11. Dynamic Human Body Modeling Using a Single RGB Camera.

    PubMed

    Zhu, Haiyu; Yu, Yao; Zhou, Yu; Du, Sidan

    2016-01-01

    In this paper, we present a novel automatic pipeline to build personalized parametric models of dynamic people using a single RGB camera. Compared to previous approaches that use monocular RGB images, our system can model a 3D human body automatically and incrementally, taking advantage of human motion. Based on coarse 2D and 3D poses estimated from image sequences, we first perform a kinematic classification of human body parts to refine the poses and obtain reconstructed body parts. Next, a personalized parametric human model is generated by driving a general template to fit the body parts and calculating the non-rigid deformation. Experimental results show that our shape estimation method achieves comparable accuracy with reconstructed models using depth cameras, yet requires neither user interaction nor any dedicated devices, leading to the feasibility of using this method on widely available smart phones. PMID:26999159

  12. Herbivory and body size: allometries of diet quality and gastrointestinal physiology, and implications for herbivore ecology and dinosaur gigantism.

    PubMed

    Clauss, Marcus; Steuer, Patrick; Müller, Dennis W H; Codron, Daryl; Hummel, Jürgen

    2013-01-01

    Digestive physiology has played a prominent role in explanations for terrestrial herbivore body size evolution and size-driven diversification and niche differentiation. This is based on the association of increasing body mass (BM) with diets of lower quality, and with putative mechanisms by which a higher BM could translate into a higher digestive efficiency. Such concepts, however, often do not match empirical data. Here, we review concepts and data on terrestrial herbivore BM, diet quality, digestive physiology and metabolism, and in doing so give examples for problems in using allometric analyses and extrapolations. A digestive advantage of larger BM is not corroborated by conceptual or empirical approaches. We suggest that explanatory models should shift from physiological to ecological scenarios based on the association of forage quality and biomass availability, and the association between BM and feeding selectivity. These associations mostly (but not exclusively) allow large herbivores to use low quality forage only, whereas they allow small herbivores the use of any forage they can physically manage. Examples of small herbivores able to subsist on lower quality diets are rare but exist. We speculate that this could be explained by evolutionary adaptations to the ecological opportunity of selective feeding in smaller animals, rather than by a physiologic or metabolic necessity linked to BM. For gigantic herbivores such as sauropod dinosaurs, other factors than digestive physiology appear more promising candidates to explain evolutionary drives towards extreme BM. PMID:24204552

  13. Herbivory and Body Size: Allometries of Diet Quality and Gastrointestinal Physiology, and Implications for Herbivore Ecology and Dinosaur Gigantism

    PubMed Central

    Clauss, Marcus; Steuer, Patrick; Müller, Dennis W. H.; Codron, Daryl; Hummel, Jürgen

    2013-01-01

    Digestive physiology has played a prominent role in explanations for terrestrial herbivore body size evolution and size-driven diversification and niche differentiation. This is based on the association of increasing body mass (BM) with diets of lower quality, and with putative mechanisms by which a higher BM could translate into a higher digestive efficiency. Such concepts, however, often do not match empirical data. Here, we review concepts and data on terrestrial herbivore BM, diet quality, digestive physiology and metabolism, and in doing so give examples for problems in using allometric analyses and extrapolations. A digestive advantage of larger BM is not corroborated by conceptual or empirical approaches. We suggest that explanatory models should shift from physiological to ecological scenarios based on the association of forage quality and biomass availability, and the association between BM and feeding selectivity. These associations mostly (but not exclusively) allow large herbivores to use low quality forage only, whereas they allow small herbivores the use of any forage they can physically manage. Examples of small herbivores able to subsist on lower quality diets are rare but exist. We speculate that this could be explained by evolutionary adaptations to the ecological opportunity of selective feeding in smaller animals, rather than by a physiologic or metabolic necessity linked to BM. For gigantic herbivores such as sauropod dinosaurs, other factors than digestive physiology appear more promising candidates to explain evolutionary drives towards extreme BM. PMID:24204552

  14. Molecular Physiology of an Extra-renal Cl- Uptake Mechanism for Body Fluid Cl- Homeostasis

    PubMed Central

    Wang, Yi-Fang; Yan, Jia-Jiun; Tseng, Yung-Che; Chen, Ruo-Dong; Hwang, Pung-Pung

    2015-01-01

    The development of an ion regulatory mechanism for body fluid homeostasis was an important trait for vertebrates during the evolution from aquatic to terrestrial life. The homeostatic mechanism of Cl- in aquatic fish appears to be similar to that of terrestrial vertebrates; however, the mechanism in non-mammalian vertebrates is poorly understood. Unlike in mammals, in which the kidney plays a central role, in most fish species, the gill is responsible for the maintenance of Cl- homeostasis via Cl- transport uptake mechanisms. Previous studies in zebrafish identified Na+-Cl- cotransporter (NCC) 2b-expressing cells in the gills and skin as the major ionocytes responsible for Cl- uptake, similar to distal convoluted tubular cells in mammalian kidney. However, the mechanism by which basolateral ions exit from NCC cells is still unclear. Of the in situ hybridization signals of twelve members of the clc Cl- channel family, only that of clc-2c exhibited an ionocyte pattern in the gill and embryonic skin. Double in situ hybridization/immunocytochemistry confirmed colocalization of apical NCC2b with basolateral CLC-2c. Acclimation to a low Cl- environment increased mRNA expression of both clc-2c and ncc2b, and also the protein expression of CLC-2c in embryos and adult gills. Loss-of-function of clc-2c resulted in a significant decrease in whole body Cl- content in zebrafish embryos, a phenotype similar to that of ncc2b mutants; this finding suggests a role for CLC-2c in Cl- uptake. Translational knockdown of clc-2c stimulated ncc2b mRNA expression and vice versa, revealing cooperation between these two transporters in the context of zebrafish Cl- homeostasis. Further comparative genomic and phylogenetic analyses revealed that zebrafish CLC-2c is a fish-specific isoform that diverged from a kidney-predominant homologue, in the same manner as NCC2b and its counterparts (NCCs). Several lines of molecular and cellular physiological evidences demonstrated the cofunctional role

  15. Molecular Physiology of an Extra-renal Cl(-) Uptake Mechanism for Body Fluid Cl(-) Homeostasis.

    PubMed

    Wang, Yi-Fang; Yan, Jia-Jiun; Tseng, Yung-Che; Chen, Ruo-Dong; Hwang, Pung-Pung

    2015-01-01

    The development of an ion regulatory mechanism for body fluid homeostasis was an important trait for vertebrates during the evolution from aquatic to terrestrial life. The homeostatic mechanism of Cl(-) in aquatic fish appears to be similar to that of terrestrial vertebrates; however, the mechanism in non-mammalian vertebrates is poorly understood. Unlike in mammals, in which the kidney plays a central role, in most fish species, the gill is responsible for the maintenance of Cl(-) homeostasis via Cl(-) transport uptake mechanisms. Previous studies in zebrafish identified Na(+)-Cl(-) cotransporter (NCC) 2b-expressing cells in the gills and skin as the major ionocytes responsible for Cl(-) uptake, similar to distal convoluted tubular cells in mammalian kidney. However, the mechanism by which basolateral ions exit from NCC cells is still unclear. Of the in situ hybridization signals of twelve members of the clc Cl(-) channel family, only that of clc-2c exhibited an ionocyte pattern in the gill and embryonic skin. Double in situ hybridization/immunocytochemistry confirmed colocalization of apical NCC2b with basolateral CLC-2c. Acclimation to a low Cl(-) environment increased mRNA expression of both clc-2c and ncc2b, and also the protein expression of CLC-2c in embryos and adult gills. Loss-of-function of clc-2c resulted in a significant decrease in whole body Cl(-) content in zebrafish embryos, a phenotype similar to that of ncc2b mutants; this finding suggests a role for CLC-2c in Cl(-) uptake. Translational knockdown of clc-2c stimulated ncc2b mRNA expression and vice versa, revealing cooperation between these two transporters in the context of zebrafish Cl(-) homeostasis. Further comparative genomic and phylogenetic analyses revealed that zebrafish CLC-2c is a fish-specific isoform that diverged from a kidney-predominant homologue, in the same manner as NCC2b and its counterparts (NCCs). Several lines of molecular and cellular physiological evidences demonstrated

  16. Clinical, Biomechanical, and Physiological Translational Interpretations of Human Resting Myofascial Tone or Tension

    PubMed Central

    Masi, Alfonse T.; Nair, Kalyani; Evans, Tyler; Ghandour, Yousef

    2010-01-01

    Background Myofascial tissues generate integrated webs and networks of passive and active tensional forces that provide stabilizing support and that control movement in the body. Passive [central nervous system (CNS)–independent] resting myofascial tension is present in the body and provides a low-level stabilizing component to help maintain balanced postures. This property was recently called “human resting myofascial tone” (HRMT). The HRMT model evolved from electromyography (EMG) research in the 1950s that showed lumbar muscles usually to be EMG-silent in relaxed gravity-neutral upright postures. Methods Biomechanical, clinical, and physiological studies were reviewed to interpret the passive stiffness properties of HRMT that help to stabilize various relaxed functions such as quiet balanced standing. Biomechanical analyses and experimental studies of the lumbar multifidus were reviewed to interpret its passive stiffness properties. The lumbar multifidus was illustrated as the major core stabilizing muscle of the spine, serving an important passive biomechanical role in the body. Results Research into muscle physiology suggests that passive resting tension (CNS-independent) is generated in sarcomeres by the molecular elasticity of low-level cycling cross-bridges between the actomyosin filaments. In turn, tension is complexly transmitted to intimately enveloping fascial matrix fibrils and other molecular elements in connective tissue, which, collectively, constitute the myofascial unit. Postural myofascial tonus varies with age and sex. Also, individuals in the population are proposed to vary in a polymorphism of postural HRMT. A few people are expected to have outlier degrees of innate postural hypotonicity or hypertonicity. Such biomechanical variations likely predispose to greater risk of related musculoskeletal disorders, a situation that deserves greater attention in clinical practice and research. Axial myofascial hypertonicity was hypothesized to

  17. Predicting physiological capacity of human load carriage - a review.

    PubMed

    Drain, Jace; Billing, Daniel; Neesham-Smith, Daniel; Aisbett, Brad

    2016-01-01

    This review article aims to evaluate a proposed maximum acceptable work duration model for load carriage tasks. It is contended that this concept has particular relevance to physically demanding occupations such as military and firefighting. Personnel in these occupations are often required to perform very physically demanding tasks, over varying time periods, often involving load carriage. Previous research has investigated concepts related to physiological workload limits in occupational settings (e.g. industrial). Evidence suggests however, that existing (unloaded) workload guidelines are not appropriate for load carriage tasks. The utility of this model warrants further work to enable prediction of load carriage durations across a range of functional workloads for physically demanding occupations. If the maximum duration for which personnel can physiologically sustain a load carriage task could be accurately predicted, commanders and supervisors could better plan for and manage tasks to ensure operational imperatives were met whilst minimising health risks for their workers. PMID:26360198

  18. The physiological basis of human sexual arousal: neuroendocrine sexual asymmetry.

    PubMed

    Motofei, Ion G; Rowland, David L

    2005-04-01

    Normal sexual arousal and response suppose an integrated process involving both physiological and psychological processes. However, the current understanding of sexual arousal does not provide a coherent model that accounts for the integration of multiple physiological systems that subsequently generate a coordinated sexual response at both the spinal peripheral and cerebral central levels. Herein we suggest a model that involves both sympathetic and parasympathetic activation during sexual arousal via the two classes of gonadal hormones, androgens and oestrogens. We discuss the manner in which gonadal hormones may activate such a system, transforming pre-pubertal (non-erotic) genital stimulation to post-pubertal erogenization of stimulation and subsequent sexual arousal. Finally, we indicate that the different balance of androgens and oestrogens in men and women may generate asymmetric effects on each of the components of the autonomic nervous system, thereby explaining some of the differences in patterns of sexual arousal and the responses cycle across the sexes. PMID:15811068

  19. [Research progress on free radicals in human body].

    PubMed

    Wang, Q B; Xu, F P; Wei, C X; Peng, J; Dong, X D

    2016-08-10

    Free radicals are the intermediates of metabolism, widely exist in the human bodies. Under normal circumstances, the free radicals play an important role in the metabolic process on human body, cell signal pathway, gene regulation, induction of cell proliferation and apoptosis, so as to maintain the normal growth and development of human body and to inhibit the growth of bacteria, virus and cancer. However, when organic lesion occurs affected by external factors or when equilibrium of the free radicals is tipped in the human body, the free radicals will respond integratedly with lipids, protein or nucleic acid which may jeopardize the health of human bodies. This paper summarizes the research progress of the free radicals conducted in recent years, in relations to the perspective of the types, origins, test methods of the free radicals and their relationship with human's health. In addition, the possible mechanisms of environmental pollutants (such as polycyclic aromatic hydrocarbons) mediating oxidative stress and free radicals scavenging in the body were also summarized. PMID:27539355

  20. Geo-Effective Heliophysical Variations and Human Physiological State

    NASA Astrophysics Data System (ADS)

    Dimitrova, S.

    2006-03-01

    A group of 86 volunteers was examined on each working day in autumn 2001 and in spring 2002. These periods were chosen because of maximal expected geomagnetic activity. There were 26 persons in the group on a drug treatment, mainly because of hypertension. Systolic and diastolic blood pressure and heart rate were registered. Pulse pressure was calculated. Data about subjective psycho-physiological complaints of the persons examined were also gathered. Altogether 2799 recordings were obtained and analyzed. MANOVA was employed to check the significance of the influence of three factors on the physiological parameters under consideration. The factors were as follows: 1) geomagnetic activity estimated by H-component of the local geomagnetic field and divided into five levels; 2) gender - males and females; 3) presence of medication. Post hoc analysis was performed to elicit the significance of differences in the factors' levels. The average arterial blood pressure, pulse pressure and the percentage of the persons in the group with subjective psycho-physiological complaints were found to increase significantly with the increase of geomagnetic activity. The maximal increment of systolic and diastolic blood pressure was 10-11% and for pulse pressure 13.6%. Analyses revealed that females and persons on a medication were more sensitive to the increase of geomagnetic activity than respectively males and persons with no medication.

  1. Complexity analysis of human physiological signals based on case studies

    NASA Astrophysics Data System (ADS)

    Angelova, Maia; Holloway, Philip; Ellis, Jason

    2015-04-01

    This work focuses on methods for investigation of physiological time series based on complexity analysis. It is a part of a wider programme to determine non-invasive markers for healthy ageing. We consider two case studies investigated with actigraphy: (a) sleep and alternations with insomnia, and (b) ageing effects on mobility patterns. We illustrate, using these case studies, the application of fractal analysis to the investigation of regulation patterns and control, and change of physiological function. In the first case study, fractal analysis techniques were implemented to study the correlations present in sleep actigraphy for individuals suffering from acute insomnia in comparison with healthy controls. The aim was to investigate if complexity analysis can detect the onset of adverse health-related events. The subjects with acute insomnia displayed significantly higher levels of complexity, possibly a result of too much activity in the underlying regulatory systems. The second case study considered mobility patterns during night time and their variations with age. It showed that complexity metrics can identify change in physiological function with ageing. Both studies demonstrated that complexity analysis can be used to investigate markers of health, disease and healthy ageing.

  2. A Circuit Model of Real Time Human Body Hydration.

    PubMed

    Asogwa, Clement Ogugua; Teshome, Assefa K; Collins, Stephen F; Lai, Daniel T H

    2016-06-01

    Changes in human body hydration leading to excess fluid losses or overload affects the body fluid's ability to provide the necessary support for healthy living. We propose a time-dependent circuit model of real-time human body hydration, which models the human body tissue as a signal transmission medium. The circuit model predicts the attenuation of a propagating electrical signal. Hydration rates are modeled by a time constant τ, which characterizes the individual specific metabolic function of the body part measured. We define a surrogate human body anthropometric parameter θ by the muscle-fat ratio and comparing it with the body mass index (BMI), we find theoretically, the rate of hydration varying from 1.73 dB/min, for high θ and low τ to 0.05 dB/min for low θ and high τ. We compare these theoretical values with empirical measurements and show that real-time changes in human body hydration can be observed by measuring signal attenuation. We took empirical measurements using a vector network analyzer and obtained different hydration rates for various BMI, ranging from 0.6 dB/min for 22.7 [Formula: see text] down to 0.04 dB/min for 41.2 [Formula: see text]. We conclude that the galvanic coupling circuit model can predict changes in the volume of the body fluid, which are essential in diagnosing and monitoring treatment of body fluid disorder. Individuals with high BMI would have higher time-dependent biological characteristic, lower metabolic rate, and lower rate of hydration. PMID:26485354

  3. Inactivation of human interferon by body fluids

    NASA Technical Reports Server (NTRS)

    Cesario, T. C.; Mandell, A.; Tilles, J. G.

    1973-01-01

    Description of the effects of human feces, bile, saliva, serum, and cerebrospinal fluid on interferon activity. It is shown that crude interferon is inactivated by at least 50% more than with the control medium used, when incubated for 4 hr in vitro in the presence of serum, saliva, or cerebrospinal liquid, and by close to 100% when incubated with stool extract or bile.

  4. [The need for a law concerning human body rights].

    PubMed

    Lachaux, B; Lemoine, P

    1991-01-01

    This new "turn of the century", at least in France, is marked by an increasing discrepancy between laws and new medical discoveries. Medical practitioners, scientists and researchers have had such a fantastic power and, as a consequence, the patients have never run such an important risk of loosing human dimensions. The basic question is the legal status of the human body. Until now, common law considers human being as a citizen whose liberty should be limited under certain conditions. However, this point of view poorly prepares to rule man as a creature of flesh and sentiment. There is an almost complete deficit of the legal statute of man in his globality, especially concerning the juridical status of the human body which is totally lacking as a whole in the french civil code. Human body represents a double legal problem: is its integrity a private or a public privilege? Are his dignity and identity really warranted for everyone? PMID:1669028

  5. Three-dimensional surface anthropometry: Applications to the human body

    NASA Astrophysics Data System (ADS)

    Jones, Peter R. M.; Rioux, Marc

    1997-09-01

    Anthropometry is the study of the measurement of the human body. By tradition this has been carried out taking the measurements from body surface landmarks, such as circumferences and breadths, using simple instruments like tape measures and calipers. Three-dimensional (3D) surface anthropometry enables us to extend the study to 3D geometry and morphology of mainly external human body tissues. It includes the acquisition, indexing, transmission, archiving, retrieval, interrogation and analysis of body size, shape, and surface together with their variability throughout growth and development to adulthood. While 3D surface anthropometry surveying is relatively new, anthropometric surveying using traditional tools, such as calipers and tape measures, is not. Recorded studies of the human form date back to ancient times. Since at least the 17th century 1 investigators have made attempts to measure the human body for physical properties such as weight, size, and centre of mass. Martin documented 'standard' body measurement methods in a handbook in 1928. 2 This paper reviews the past and current literature devoted to the applications of 3D anthropometry because true 3D scanning of the complete human body is fast becoming a reality. We attempt to take readers through different forms of technology which deal with simple forms of projected light to the more complex advanced forms of laser and video technology giving low and/or high resolution 3D data. Information is also given about image capture of size and shape of the whole as well as most component parts of the human body. In particular, the review describes with explanations a multitude of applications, for example, medical, product design, human engineering, anthropometry and ergonomics etc.

  6. Comparison of body cooling methods on physiological and perceptual measures of mildly hyperthermic athletes.

    PubMed

    DeMartini, Julie K; Ranalli, Gregory F; Casa, Douglas J; Lopez, Rebecca M; Ganio, Matthew S; Stearns, Rebecca L; McDermott, Brendon P; Armstrong, Lawrence E; Maresh, Carl M

    2011-08-01

    Hyperthermia is common among athletes and in a variety of environments. The purpose of this study was to evaluate the effectiveness of cooling methods on core body temperature, heart rate (HR), and perceptual readings in individuals after exercise. Sixteen subjects (age: 24 ± 6 years, height: 182 ± 7 cm, weight: 74.03 ± 9.17 kg, and body fat: 17.08 ± 6.23%) completed 10 exercise sessions in warm conditions (WBGT: 26.64 ± 4.71°C) followed by body cooling by 10 different methods. Cooling methods included cold water immersion (CWI), shade, Port-a-Cool® (FAN), Emergency Cold Containment System® (ECCS), Rehab. Hood® (HOOD), Game Ready Active Cooling Vest™ (GRV), Nike Ice Vest™ (NIV), ice buckets (IBs), and ice towels (IT). These cooling modes were compared with a control (SUN). Rectal temperature (T(re)), HR, thermal sensation, thirst sensation, and a 56-question Environmental Symptoms Questionnaire (ESQ) were used to assess physiological and perceptual data. Average T(re) after exercise across all trials was 38.73 ± 0.12°C. After 10 minutes of cooling, CWI (-0.65 ± 0.29°C), ECCS (-0.68 ± 0.24°C), and IB (-0.74 ± 0.34°C) had significantly (p < 0.006) greater decreases in T(re) compared with that in SUN (-0.42 ± 0.15°C). The HR after 10 minutes of cooling was significantly (p < 0.006) lower for CWI (82 ± 15 b·min(-1)), ECCS (87 ± 14 b·min(-1)), and IT (84 ± 15 b·min(-1)) when compared with SUN (101 ± 15 b·min(-1)). The thermal sensation between modalities was all significantly (p < 0.006) lower (CWI: 1.5 ± 0.5; Fan: 3.0 ± 1.0; ECCS: 4.5 ± 1.0; Hood: 4.5 ± 0.5; GRV: 4.0 ± 0.5; NIV: 4.5 ± 1.0; IB: 4.0 ± 1.0; IT: 3.0 ± 1.0) when compared with SUN (5.5 ± 0.5), except for Shade (5.0 ± 1.0). There were no significant differences (p > 0.006) in thirst sensation between modalities. The ESQ scores were significantly (p < 0.006) lower for CWI (1 ± 6), Fan (4 ± 5), and IT (3 ± 8) compared with that for SUN (13 ± 12). In conclusion, when

  7. Virtual Patients and Sensitivity Analysis of the Guyton Model of Blood Pressure Regulation: Towards Individualized Models of Whole-Body Physiology

    PubMed Central

    Moss, Robert; Grosse, Thibault; Marchant, Ivanny; Lassau, Nathalie; Gueyffier, François; Thomas, S. Randall

    2012-01-01

    Mathematical models that integrate multi-scale physiological data can offer insight into physiological and pathophysiological function, and may eventually assist in individualized predictive medicine. We present a methodology for performing systematic analyses of multi-parameter interactions in such complex, multi-scale models. Human physiology models are often based on or inspired by Arthur Guyton's whole-body circulatory regulation model. Despite the significance of this model, it has not been the subject of a systematic and comprehensive sensitivity study. Therefore, we use this model as a case study for our methodology. Our analysis of the Guyton model reveals how the multitude of model parameters combine to affect the model dynamics, and how interesting combinations of parameters may be identified. It also includes a “virtual population” from which “virtual individuals” can be chosen, on the basis of exhibiting conditions similar to those of a real-world patient. This lays the groundwork for using the Guyton model for in silico exploration of pathophysiological states and treatment strategies. The results presented here illustrate several potential uses for the entire dataset of sensitivity results and the “virtual individuals” that we have generated, which are included in the supplementary material. More generally, the presented methodology is applicable to modern, more complex multi-scale physiological models. PMID:22761561

  8. Categorical discrimination of human body parts by magnetoencephalography

    PubMed Central

    Nakamura, Misaki; Yanagisawa, Takufumi; Okamura, Yumiko; Fukuma, Ryohei; Hirata, Masayuki; Araki, Toshihiko; Kamitani, Yukiyasu; Yorifuji, Shiro

    2015-01-01

    Humans recognize body parts in categories. Previous studies have shown that responses in the fusiform body area (FBA) and extrastriate body area (EBA) are evoked by the perception of the human body, when presented either as whole or as isolated parts. These responses occur approximately 190 ms after body images are visualized. The extent to which body-sensitive responses show specificity for different body part categories remains to be largely clarified. We used a decoding method to quantify neural responses associated with the perception of different categories of body parts. Nine subjects underwent measurements of their brain activities by magnetoencephalography (MEG) while viewing 14 images of feet, hands, mouths, and objects. We decoded categories of the presented images from the MEG signals using a support vector machine (SVM) and calculated their accuracy by 10-fold cross-validation. For each subject, a response that appeared to be a body-sensitive response was observed and the MEG signals corresponding to the three types of body categories were classified based on the signals in the occipitotemporal cortex. The accuracy in decoding body-part categories (with a peak at approximately 48%) was above chance (33.3%) and significantly higher than that for random categories. According to the time course and location, the responses are suggested to be body-sensitive and to include information regarding the body-part category. Finally, this non-invasive method can decode category information of a visual object with high temporal and spatial resolution and this result may have a significant impact in the field of brain–machine interface research. PMID:26582986

  9. Earthing: health implications of reconnecting the human body to the Earth's surface electrons.

    PubMed

    Chevalier, Gaétan; Sinatra, Stephen T; Oschman, James L; Sokal, Karol; Sokal, Pawel

    2012-01-01

    Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits-including better sleep and reduced pain-from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance. PMID:22291721

  10. An implicit body representation underlying human position sense.

    PubMed

    Longo, Matthew R; Haggard, Patrick

    2010-06-29

    Knowing the body's location in external space is a fundamental perceptual task. Perceiving the location of body parts through proprioception requires that information about the angles of each joint (i.e., body posture) be combined with information about the size and shape of the body segments between joints. Although information about body posture is specified by on-line afferent signals, no sensory signals are directly informative about body size and shape. Thus, human position sense must refer to a stored body model of the body's metric properties, such as body part size and shape. The need for such a model has long been recognized; however, the properties of this model have never been systematically investigated. We developed a technique to isolate and measure this body model. Participants judged the location in external space of 10 landmarks on the hand. By analyzing the internal configuration of the locations of these points, we produced implicit maps of the mental representation of hand size and shape. We show that this part of the body model is massively distorted, in a reliable and characteristic fashion, featuring shortened fingers and broadened hands. Intriguingly, these distortions appear to retain several characteristics of primary somatosensory representations, such as the Penfield homunculus. PMID:20547858

  11. Alliances in Human Biology: The Harvard Committee on Industrial Physiology, 1929-1939.

    PubMed

    Oakes, Jason

    2015-08-01

    In 1929 the newly-reorganized Rockefeller Foundation funded the work of a cross-disciplinary group at Harvard University called the Committee on Industrial Physiology (CIP). The committee's research and pedagogical work was oriented towards different things for different members of the alliance. The CIP program included a research component in the Harvard Fatigue Laboratory and Elton May's interpretation of the Hawthorne Studies; a pedagogical aspect as part of Wallace Donham's curriculum for Harvard Business School; and Lawrence Henderson's work with the Harvard Pareto Circle, his course Sociology 23, and the Harvard Society of Fellows. The key actors within the CIP alliance shared a concern with training men for elite careers in government service, business leadership, and academic prominence. But the first communications between the CIP and the Rockefeller Foundation did not emphasize training in human biology. Instead, the CIP presented itself as a coordinating body that would be able to organize all the varied work going on at Harvard that did not fit easily into one department, and it was on this basis that the CIP became legible to the President of Harvard, A. Lawrence Lowell, and to Rockefeller's Division of Social Sciences. The members of the CIP alliance used the term human biology for this project of research, training and institutional coordination. PMID:26024783

  12. "Sebocytes' makeup": novel mechanisms and concepts in the physiology of the human sebaceous glands.

    PubMed

    Tóth, Balázs I; Oláh, Attila; Szöllosi, Attila G; Czifra, Gabriella; Bíró, Tamás

    2011-06-01

    The pilosebaceous unit of the human skin consists of the hair follicle and the sebaceous gland. Within this "mini-organ", the sebaceous gland has been neglected by the researchers of the field for several decades. Actually, it was labeled as a reminiscence of human development ("a living fossil with a past but no future"), and was thought to solely act as a producer of sebum, a lipid-enriched oily substance which protects our skin (and hence the body) against various insults. However, due to emerging research activities of the past two decades, it has now become evident that the sebaceous gland is not only a "passive" cutaneous "relic" to establish the physico-chemical barrier function of the skin against constant environmental challenges, but it rather functions as an "active" neuro-immuno-endocrine cutaneous organ. This review summarizes recent findings of sebaceous gland research by mainly focusing on newly discovered physiological functions, novel regulatory mechanisms, key events in the pathology of the gland, and future directions in both experimental and clinical dermatology. PMID:21384129

  13. Representational Similarity of Body Parts in Human Occipitotemporal Cortex.

    PubMed

    Bracci, Stefania; Caramazza, Alfonso; Peelen, Marius V

    2015-09-23

    Regions in human lateral and ventral occipitotemporal cortices (OTC) respond selectively to pictures of the human body and its parts. What are the organizational principles underlying body part responses in these regions? Here we used representational similarity analysis (RSA) of fMRI data to test multiple possible organizational principles: shape similarity, physical proximity, cortical homunculus proximity, and semantic similarity. Participants viewed pictures of whole persons, chairs, and eight body parts (hands, arms, legs, feet, chests, waists, upper faces, and lower faces). The similarity of multivoxel activity patterns for all body part pairs was established in whole person-selective OTC regions. The resulting neural similarity matrices were then compared with similarity matrices capturing the hypothesized organizational principles. Results showed that the semantic similarity model best captured the neural similarity of body parts in lateral and ventral OTC, which followed an organization in three clusters: (1) body parts used as action effectors (hands, feet, arms, and legs), (2) noneffector body parts (chests and waists), and (3) face parts (upper and lower faces). Whole-brain RSA revealed, in addition to OTC, regions in parietal and frontal cortex in which neural similarity was related to semantic similarity. In contrast, neural similarity in occipital cortex was best predicted by shape similarity models. We suggest that the semantic organization of body parts in high-level visual cortex relates to the different functions associated with the three body part clusters, reflecting the unique processing and connectivity demands associated with the different types of information (e.g., action, social) different body parts (e.g., limbs, faces) convey. Significance statement: While the organization of body part representations in motor and somatosensory cortices has been well characterized, the principles underlying body part representations in visual cortex

  14. The human cerebellum: a review of physiologic neuroanatomy.

    PubMed

    Roostaei, Tina; Nazeri, Arash; Sahraian, Mohammad Ali; Minagar, Alireza

    2014-11-01

    The cerebellum resides in the posterior cranial fossa dorsal to the brainstem and has diverse connections to the cerebrum, brain stem, and spinal cord. It is anatomically and physiologically divided into distinct functional compartments and is composed of highly regular arrays of neuronal units, each sharing the same basic cerebellar microcircuitry. Its circuitry is critically involved in motor control and motor learning, and its role in nonmotor cognitive and affective functions is becoming increasingly recognized. This article describes the cerebellar gross and histologic neuroanatomy in relation to its function, and the relevance of cerebellar circuitry and firing patterns to motor learning. PMID:25439284

  15. Relationship between alertness, performance, and body temperature in humans

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth P Jr; Hull, Joseph T.; Czeisler, Charles A.

    2002-01-01

    Body temperature has been reported to influence human performance. Performance is reported to be better when body temperature is high/near its circadian peak and worse when body temperature is low/near its circadian minimum. We assessed whether this relationship between performance and body temperature reflects the regulation of both the internal biological timekeeping system and/or the influence of body temperature on performance independent of circadian phase. Fourteen subjects participated in a forced desynchrony protocol allowing assessment of the relationship between body temperature and performance while controlling for circadian phase and hours awake. Most neurobehavioral measures varied as a function of internal biological time and duration of wakefulness. A number of performance measures were better when body temperature was elevated, including working memory, subjective alertness, visual attention, and the slowest 10% of reaction times. These findings demonstrate that an increased body temperature, associated with and independent of internal biological time, is correlated with improved performance and alertness. These results support the hypothesis that body temperature modulates neurobehavioral function in humans.

  16. [Hypothermia--mechanism of action and pathophysiological changes in the human body].

    PubMed

    Sosnowski, Przemysław; Mikrut, Kinga; Krauss, Hanna

    2015-01-01

    This review focuses on the physiological responses and pathophysiological changes induced by hypothermia. Normal body function depends on its ability to maintain thermal homeostasis. The human body can be divided arbitrarily into two thermal compartments: a core compartment (trunk and head), with precisely regulated temperature around 37°C, and a peripheral compartment (skin and extremities) with less strictly controlled temperature, and lower than the core temperature. Thermoregulatory processes occur in three phases: afferent thermal sensing, central regulation, mainly by the preoptic area of the anterior hypothalamus, and efferent response. Exposure to cold induces thermoregulatory responses including cutaneous vasoconstriction, shivering and non-shivering thermogenesis, and behavioral changes. Alterations of body temperature associated with impaired thermoregulation, decreased heat production or increased heat loss can lead to hypothermia. Hypothermia is defined as a core body temperature below 35ºC, and may be classified according to the origin as accidental (e.g. caused by exposure to a cold environment, drugs, or illness) or intentional (i.e. therapeutic), or by the degree of hypothermia as mild, moderate or severe. Classification by temperature is not universal. Lowering of body temperature disrupts the physiological processes at the molecular, cellular and system level, but hypothermia induced prior to cardiosurgical or neurosurgical procedures, by the decrease in tissue oxygen demand, can reduce the risk of cerebral or cardiac ischemic damage. Therapeutic hypothermia has been recommended as a clinical procedure in situations characterized by ischemia, such as cardiac arrest, stroke and brain injuries. PMID:25614675

  17. Size Variation in Small-Bodied Humans from Palau, Micronesia

    PubMed Central

    Gallagher, Andrew

    2008-01-01

    Background Recent discoveries on Palau are claimed to represent the remains of small-bodied humans that may display evidence insular size reduction. This claim has yet to be statistically validated Methodology/Principal Findings Published postcranial specimens (n = 16) from Palau were assessed relative to recent small-bodied comparative samples. Resampling statistical approaches were employed to test specific hypotheses relating to body size in the Palau sample. Results confirm that the Palau postcranial sample is indisputably small-bodied. Conclusions/Significance A single, homogenous body size morph is represented in early prehistoric postcrania from Palau. Small body size in early Palauans is an ancestral characteristic and was likely not a consequence of in-situ size reduction. Specimens from Palau have little bearing upon hypothesised insular size reduction in the ancestral lineage of Homo floresiensis. PMID:19088844

  18. Gastrointestinal Physiology During Head Down Tilt Bedrest in Human Subjects

    NASA Technical Reports Server (NTRS)

    Vaksman, Z.; Guthienz, J.; Putcha, L.

    2008-01-01

    Introduction: Gastrointestinal (GI) motility plays a key role in the physiology and function of the GI tract. It directly affects absorption of medications and nutrients taken by mouth, in addition to indirectly altering GI physiology by way of changes in the microfloral composition and biochemistry of the GI tract. Astronauts have reported nausea, loss of appetite and constipation during space flight all of which indicate a reduction in GI motility and function similar to the one seen in chronic bed rest patients. The purpose of this study is to determine GI motility and bacterial proliferation during -6 degree head down tilt bed rest (HTD). Methods: Healthy male and female subjects between the ages of 25-40 participated in a 60 day HTD study protocol. GI transit time (GITT) was determined using lactulose breath hydrogen test and bacterial overgrowth was measured using glucose breath hydrogen test. H. Pylori colonization was determined using C13-urea breath test (UBIT#). All three tests were conducted on 9 days before HDT, and repeated on HDT days 2, 28, 58, and again on day 7 after HDT. Results: GITT increased during HTD compared to the respective ambulatory control values; GITT was significantly lower on day 7 after HTD. A concomitant increase in bacterial colonization was also noticed during HDT starting after approximately 28 days of HDT. However, H. Pylori proliferation was not recorded during HDT as indicated by UBIT#. Conclusion: GITT significantly decreased during HDT with a concomitant increase in the proliferation of GI bacterial flora but not H. pylori.

  19. Acute Physiological and Behavioral Effects of Intranasal Methamphetamine in Humans

    PubMed Central

    Hart, Carl L; Gunderson, Erik W; Perez, Audrey; Kirkpatrick, Matthew G; Thurmond, Andrew; Comer, Sandra D; Foltin, Richard W

    2016-01-01

    Intranasal methamphetamine abuse has increased dramatically in the past decade, yet only one published study has investigated its acute effects under controlled laboratory conditions. Thus, the current study examined the effects of single-dose intranasal methamphetamine administration on a broad range of behavioral and physiological measures. Eleven nontreatment-seeking methamphetamine abusers (two females, nine males) completed this four-session, in-patient, within-participant, double-blind study. During each session, one of four intranasal methamphetamine doses (0, 12, 25, and 50 mg/70 kg) was administered and methamphetamine plasma concentrations, cardiovascular, subjective, and psychomotor/cognitive performance effects were assessed before drug administration and repeatedly thereafter. Following drug administration, methamphetamine plasma concentrations systematically increased for 4 h postdrug administration then declined. Methamphetamine dose dependently increased cardiovascular measures and ‘positive’ subjective effects, with peaks occurring approximately 5–15 min after drug administration, when plasma levels were still ascending. In addition, cognitive performance on less complicated tasks was improved by all active methamphetamine doses, whereas performance on more complicated tasks was improved only by the intermediate doses (12 and 25 mg). These results show that intranasal methamphetamine produced predictable effects on multiple behavioral and physiological measures before peak plasma levels were observed. Of interest is the dissociation between methamphetamine plasma concentrations with cardiovascular measures and positive subjective effects, which might have important implications for potential toxicity after repeated doses. PMID:17851535

  20. False-positive uptake on radioiodine whole-body scintigraphy: physiologic and pathologic variants unrelated to thyroid cancer

    PubMed Central

    Oh, Jong-Ryool; Ahn, Byeong-Cheol

    2012-01-01

    Radioiodine whole-body scintigraphy (WBS), which takes advantage of the high avidity of radioiodine in the functioning thyroid tissues, has been used for detection of differentiated thyroid cancer. Radioiodine is a sensitive marker for detection of thyroid cancer; however, radioiodine uptake is not specific for thyroid tissue. It can also be seen in healthy tissue, including thymus, breast, liver, and gastrointestinal tract, or in benign diseases, such as cysts and inflammation, or in a variety of benign and malignant non-thyroidal tumors, which could be mistaken for thyroid cancer. In order to accurately interpret radioiodine scintigraphy results, one must be familiar with the normal physiologic distribution of the tracer and frequently encountered physiologic and pathologic variants of radioiodine uptake. This article will provide a systematic overview of potential false-positive uptake of radioiodine in the whole body and illustrate how such unexpected findings can be appropriately evaluated. PMID:23133823

  1. Human motor adaptation in whole body motion

    PubMed Central

    Babič, Jan; Oztop, Erhan; Kawato, Mitsuo

    2016-01-01

    The main role of the sensorimotor system of an organism is to increase the survival of the species. Therefore, to understand the adaptation and optimality mechanisms of motor control, it is necessary to study the sensorimotor system in terms of ecological fitness. We designed an experimental paradigm that exposed sensorimotor system to risk of injury. We studied human subjects performing uncon- strained squat-to-stand movements that were systematically subjected to non-trivial perturbation. We found that subjects adapted by actively compensating the perturbations, converging to movements that were different from their normal unperturbed squat-to-stand movements. Furthermore, the adapted movements had clear intrinsic inter-subject differences which could be explained by different adapta- tion strategies employed by the subjects. These results suggest that classical optimality measures of physical energy and task satisfaction should be seen as part of a hierarchical organization of optimality with safety being at the highest level. Therefore, in addition to physical energy and task fulfillment, the risk of injury and other possible costs such as neural computational overhead have to be considered when analyzing human movement. PMID:27608652

  2. Human motor adaptation in whole body motion.

    PubMed

    Babič, Jan; Oztop, Erhan; Kawato, Mitsuo

    2016-01-01

    The main role of the sensorimotor system of an organism is to increase the survival of the species. Therefore, to understand the adaptation and optimality mechanisms of motor control, it is necessary to study the sensorimotor system in terms of ecological fitness. We designed an experimental paradigm that exposed sensorimotor system to risk of injury. We studied human subjects performing uncon- strained squat-to-stand movements that were systematically subjected to non-trivial perturbation. We found that subjects adapted by actively compensating the perturbations, converging to movements that were different from their normal unperturbed squat-to-stand movements. Furthermore, the adapted movements had clear intrinsic inter-subject differences which could be explained by different adapta- tion strategies employed by the subjects. These results suggest that classical optimality measures of physical energy and task satisfaction should be seen as part of a hierarchical organization of optimality with safety being at the highest level. Therefore, in addition to physical energy and task fulfillment, the risk of injury and other possible costs such as neural computational overhead have to be considered when analyzing human movement. PMID:27608652

  3. Natural User Interface Sensors for Human Body Measurement

    NASA Astrophysics Data System (ADS)

    Boehm, J.

    2012-08-01

    The recent push for natural user interfaces (NUI) in the entertainment and gaming industry has ushered in a new era of low cost three-dimensional sensors. While the basic idea of using a three-dimensional sensor for human gesture recognition dates some years back it is not until recently that such sensors became available on the mass market. The current market leader is PrimeSense who provide their technology for the Microsoft Xbox Kinect. Since these sensors are developed to detect and observe human users they should be ideally suited to measure the human body. We describe the technology of a line of NUI sensors and assess their performance in terms of repeatability and accuracy. We demonstrate the implementation of a prototype scanner integrating several NUI sensors to achieve full body coverage. We present the results of the obtained surface model of a human body.

  4. The physiological basis of reaction norms: the interaction among growth rate, the duration of growth and body size.

    PubMed

    Davidowitz, Goggy; Nijhout, H Frederik

    2004-12-01

    The general effects of temperature and nutritional quality on growth rate and body size are well known. We know little, however, about the physiological mechanisms by which an organism translates variation in diet and temperature into reaction norms of body size or development time. We outline an endocrine-based physiological mechanism that helps explain how this translation occurs in the holometabolous insect Manduca sexta (Sphingidae). Body size and development time are controlled by three factors: (i) growth rate, (ii) the timing of the cessation of juvenile hormone secretion (measured by the critical weight) and (iii) the timing of ecdysteroid secretion leading to pupation (the interval to cessation of growth [ICG] after reaching the critical weight). Thermal reaction norms of body size and development time are a function of how these three factors interact with temperature. Body size is smaller at higher temperatures, because the higher growth rate decreases the ICG, thereby reducing the amount of mass that can accumulate. Development time is shorter at higher temperatures because the higher growth rate decreases the time required to attain the critical weight and, independently, controls the duration of the ICG. Life history evolution along altitudinal, latitudinal and seasonal gradients may occur through differential selection on growth rate and the duration of the two independently controlled determinants of the growth period. PMID:21676730

  5. [Human atrial natriuretic peptide: a secretory product of the heart and its significance for physiology and clinical practice].

    PubMed

    Vierhapper, H; Waldhäusl, W

    1987-03-01

    This review deals with the physiological and clinical importance of human atrial natriuretic peptide (hANP). This peptide, which is produced by the myocardial cells of the right atrium, induces a diuretic and natriuretic response and has an inhibitory effect on aldosterone secretion. Recent elucidation of the peptide's structure represents the latest achievement in the search for an endogenous, natriuretic and hypotensive substance and has resulted in the publication of much, partly only preliminary data of its role within the homeostatic control of body sodium and water, as well as in various pathological disorders. The extensive literature is reviewed. PMID:2953110

  6. Body mass estimates of hominin fossils and the evolution of human body size.

    PubMed

    Grabowski, Mark; Hatala, Kevin G; Jungers, William L; Richmond, Brian G

    2015-08-01

    Body size directly influences an animal's place in the natural world, including its energy requirements, home range size, relative brain size, locomotion, diet, life history, and behavior. Thus, an understanding of the biology of extinct organisms, including species in our own lineage, requires accurate estimates of body size. Since the last major review of hominin body size based on postcranial morphology over 20 years ago, new fossils have been discovered, species attributions have been clarified, and methods improved. Here, we present the most comprehensive and thoroughly vetted set of individual fossil hominin body mass predictions to date, and estimation equations based on a large (n = 220) sample of modern humans of known body masses. We also present species averages based exclusively on fossils with reliable taxonomic attributions, estimates of species averages by sex, and a metric for levels of sexual dimorphism. Finally, we identify individual traits that appear to be the most reliable for mass estimation for each fossil species, for use when only one measurement is available for a fossil. Our results show that many early hominins were generally smaller-bodied than previously thought, an outcome likely due to larger estimates in previous studies resulting from the use of large-bodied modern human reference samples. Current evidence indicates that modern human-like large size first appeared by at least 3-3.5 Ma in some Australopithecus afarensis individuals. Our results challenge an evolutionary model arguing that body size increased from Australopithecus to early Homo. Instead, we show that there is no reliable evidence that the body size of non-erectus early Homo differed from that of australopiths, and confirm that Homo erectus evolved larger average body size than earlier hominins. PMID:26094042

  7. Physiologic and Functional Responses of MS Patients to Body Cooling Using Commercially Available Cooling Garments

    NASA Technical Reports Server (NTRS)

    Ku, Yu-Tsuan E.; Montgomery, Leslie D.; Lee, Hank C.; Luna, Bernadette; Webbon, Bruce W.; Mead, Susan C. (Technical Monitor)

    1999-01-01

    Personal cooling systems are widely used in industrial and aerospace environments to alleviate thermal stress. Increasingly they are also used by heat sensitive multiple sclerosis (HSMS) patients to relieve symptoms and improve quality of life. There are a variety of cooling systems commercially available to the MS community. However, little information is available regarding the comparative physiological changes produced by routine operation of these various systems. The objective of this study was to document and compare the patient response to two passive cooling vests and one active cooling garment. The Life Enhancement Technology, Inc. (LET) lightweight active cooling vest with cap, the MicroClimate Systems (MCS) Change of Phase garment, and the Steele Vest were each used to cool 13 male and 13 female MS subjects (31 to 67 yr.) in this study. The subjects, seated in an upright position at normal room temperature (approximately 22 C), were tested with one of the cooling garments. Oral, fight and left ear temperatures were logged manually every 5 min. An-n, leg, chest and rectal temperatures; heart rate; and respiration were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. Each subject was given a series of subjective and objective evaluation tests before and after cooling. The LET and Steele vests test groups had similar, significant (P less than 0.01) cooling effects on oral and ear canal temperature, which decreased approximately 0.4 C, and 0.3 C, respectively. Core temperature increased (N.S.) with all three vests during cooling. The LET vest produced the coldest (P less than 0.01) skin temperature. Overall, the LET vest provided the most improvement on subjective and objective performance measures. These results show that the garment configurations tested do not elicit a similar thermal response in all MS patients. Cooling with the LET active garment configuration resulted in the lowest body temperatures for the MS subjects; cooling with

  8. The Bugs Within Our Body: The Human Microbiota.

    PubMed

    Philpott, D J; Piquette-Miller, M

    2016-06-01

    The human microbiota is the ecological community of microorganisms that live within our bodies. Emerging evidence has revealed that dysregulation of the host-microbe symbiotic relationship contributes to the pathogenesis of a vast number of human diseases and impacts the efficacy and toxicity of therapeutic drugs. Therefore, a deeper understanding of the human microbiota is crucial to the development of therapeutic interventions that target the microbiota and also provides fundamental insights towards understanding intersubject variability in therapeutic outcomes. PMID:27160649

  9. [Heme-iron in the human body].

    PubMed

    Balla, József; Balla, György; Lakatos, Béla; Jeney, Viktória; Szentmihályi, Klára

    2007-09-01

    Iron is essential for all living organism, although in excess amount it is dangerous via catalyzing the formation of reactive oxygen species. Absorption of iron is strictly controlled resulting in a fine balance of iron-loss and iron-uptake. In countries where the ingestion of heme-iron is significant by meal, great part of iron content in the body originates from heme. Heme derived from food is absorbed by a receptor-mediated manner by enterocytes of small intestine then it is degraded in a reaction catalyzed by heme oxygenase. Iron released from the porphyrin ring leaves enterocytes as transferrin associated iron. Prosthetic group of several proteins contains heme, therefore, it is synthesized by all cells. One of the most significant heme proteins is hemoglobin which transports oxygen in the erythrocytes. Hemoglobin released from erythrocyte during intravascular hemolysis binds to haptoglobin and is taken up by cells of the monocyte-macrophage lineage. Oxidation of hemoglobin (ferro) to methemoglobin (ferri) is inhibited by the structure of hemoglobin although it is not hindered. Superoxide anion is also formed in the reaction that initiates further free radical reactions. In contrast to ferrohemoglobin, methemoglobin readily releases heme, therefore, oxidation of hemoglobin drives the formation of free heme in plasma. Heme binds to a plasma protein, hemopexin, and is internalized by cells of monocyte-macrophage lineage in a receptor-mediated manner, then degraded in reaction catalysed by heme oxygenase. Heme is also taken up by plasma lipoproteins and endothelial cells leading to oxidation of LDL and subsequent endothelial cell damage. The purpose of this work was to summarize the processes related to heme. PMID:17766221

  10. Development of the ventral body wall in the human embryo.

    PubMed

    Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Köhler, S Eleonore; Lamers, Wouter H

    2015-11-01

    Migratory failure of somitic cells is the commonest explanation for ventral body wall defects. However, the embryo increases ~ 25-fold in volume in the period that the ventral body wall forms, so that differential growth may, instead, account for the observed changes in topography. Human embryos between 4 and 10 weeks of development were studied, using amira reconstruction and cinema 4D remodeling software for visualization. Initially, vertebrae and ribs had formed medially, and primordia of sternum and hypaxial flank muscle primordium laterally in the body wall at Carnegie Stage (CS)15 (5.5 weeks). The next week, ribs and muscle primordium expanded in ventrolateral direction only. At CS18 (6.5 weeks), separate intercostal and abdominal wall muscles differentiated, and ribs, sterna, and muscles began to expand ventromedially and caudally, with the bilateral sternal bars fusing in the midline after CS20 (7 weeks) and the rectus muscles reaching the umbilicus at CS23 (8 weeks). The near-constant absolute distance between both rectus muscles and approximately fivefold decline of this distance relative to body circumference between 6 and 10 weeks identified dorsoventral growth in the dorsal body wall as determinant of the 'closure' of the ventral body wall. Concomitant with the straightening of the embryonic body axis after the 6th week, the abdominal muscles expanded ventrally and caudally to form the infraumbilical body wall. Our data, therefore, show that the ventral body wall is formed by differential dorsoventral growth in the dorsal part of the body. PMID:26467243

  11. Human ketone body production and utilization studied using tracer techniques: Regulation by free fatty acids, insulin, catecholamines, and thyroid hormones

    SciTech Connect

    Keller, U.; Lustenberger, M.; Mueller-Brand, J.G.; Gerber, P.P.; Stauffacher, W.

    1989-05-01

    Ketone body concentrations fluctuate markedly during physiological and pathological conditions. Tracer techniques have been developed in recent years to study production, utilization, and the metabolic clearance rate of ketone bodies. This review describes data on the roles of insulin, catecholamines, and thyroid hormones in the regulation of ketone body kinetics. The data indicate that insulin lowers ketone body concentrations by three independent mechanisms: first, it inhibits lipolysis, and thus lowers free fatty acid availability for ketogenesis; second, it restrains ketone body production within the liver; third, it enhances peripheral ketone body utilization. To assess these effects in humans in vivo, experimental models were developed to study insulin effects with controlled concentrations of free fatty acids, insulin, glucagon, and ketone bodies. Presently available data also support an important role of catecholamines in increasing ketone body concentrations. Evidence was presented that norepinephrine increases ketogenesis not only by stimulating lipolysis, and thus releasing free fatty acids, but also by increasing intrahepatic ketogenesis. Thyroid hormone availability was associated with lipolysis and ketogenesis. Ketone body concentrations after an overnight fast were only modestly elevated in hyperthyroidism resulting from increased peripheral ketone body clearance. There was a significant correlation between serum triiodothyronine levels and the ketone body metabolic clearance rate. Thus, ketone body homeostasis in human subjects resulted from the interaction of hormones such as insulin, catecholamines, and thyroid hormones regulating lipolysis, intrahepatic ketogenesis, and peripheral ketone body utilization. 58 references.

  12. The commerce of human body parts: an Eastern Orthodox response.

    PubMed

    Reardon, P H

    2000-08-01

    The Orthodox Church teaches that the bodies of those in Christ are to be regarded as sanctified by the hearing of the Word and faithful participation in the Sacraments, most particularly the Holy Eucharist; because of the indwelling of the Holy Spirit the consecrated bodies of Christians do not belong to them but to Christ; with respect to the indwelling Holy Spirit there is no difference between the bodies of Christians before and after death; whether before or after death, the Christian body is also to receive the same veneration; and notwithstanding the physical corruptions that the body endures by reason of death, there remains a strict continuity between the body in which the Christian dies and the body in which the Christian will rise again. That is to say, it is the very same reality that is sown in corruption and will be raised in incorruption. Given such consideration, the notion of "selling" and integral part of a human being is simply outside the realm of rational comprehension. Indeed, it is profoundly repugnant to those Orthodox Christian sentiments that are formed and nourished by the Church's sacramental teaching and liturgical worship. One does not sell or purchase that which has been consecrated in those solemn ways that the Church consecrates the human body. PMID:12171078

  13. Breath-based meditation: A mechanism to restore the physiological and cognitive reserves for optimal human performance.

    PubMed

    Carter, Kirtigandha Salwe; Carter, Robert

    2016-04-16

    Stress can be associated with many physiological changes resulting in significant decrements in human performance. Due to growing interests in alternative and complementary medicine by Westerners, many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles. These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder. However, the potential of yogic breathing on optimizing human performance and overall well-being is not well known. Breathing techniques such as alternate nostril, Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness. Furthermore, yogic breathing is physiologically stimulating and can be described as a natural "technological" solution to optimize human performance which can be categorized into: (1) cognitive function (i.e., mind, vigilance); and (2) physical performance (i.e., cardiorespiratory, metabolism, exercise, whole body). Based on previous studies, we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function. This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state (i.e., hypertension, depression, dementia) or acute state (i.e., massive hemorrhage, panic attic) of medical conditions. However, additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation (i.e., breath-based, mantra, mindfulness) on human performance. These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation. While it has been suggested that breath-based meditation is easier for

  14. Breath-based meditation: A mechanism to restore the physiological and cognitive reserves for optimal human performance

    PubMed Central

    Carter, Kirtigandha Salwe; Carter III, Robert

    2016-01-01

    Stress can be associated with many physiological changes resulting in significant decrements in human performance. Due to growing interests in alternative and complementary medicine by Westerners, many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles. These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder. However, the potential of yogic breathing on optimizing human performance and overall well-being is not well known. Breathing techniques such as alternate nostril, Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness. Furthermore, yogic breathing is physiologically stimulating and can be described as a natural “technological” solution to optimize human performance which can be categorized into: (1) cognitive function (i.e., mind, vigilance); and (2) physical performance (i.e., cardiorespiratory, metabolism, exercise, whole body). Based on previous studies, we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function. This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state (i.e., hypertension, depression, dementia) or acute state (i.e., massive hemorrhage, panic attic) of medical conditions. However, additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation (i.e., breath-based, mantra, mindfulness) on human performance. These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation. While it has been suggested that breath-based meditation is easier

  15. Physiological and behavioral effects of tilt-induced body fluid shifts

    NASA Technical Reports Server (NTRS)

    Parker, D. E.; Tjernstrom, O.; Ivarsson, A.; Gulledge, W. L.; Poston, R. L.

    1983-01-01

    This paper addresses the 'fluid shift theory' of space motion sickness. The primary purpose of the research was the development of procedures to assess individual differences in response to rostral body fluid shifts on earth. Experiment I examined inner ear fluid pressure changes during head-down tilt in intact human beings. Tilt produced reliable changes. Differences among subjects and between ears within the same subject were observed. Experiment II examined auditory threshold changes during tilt. Tilt elicited increased auditory thresholds, suggesting that sensory depression may result from increased inner ear fluid pressure. Additional observations on rotation magnitude estimation during head-down tilt, which indicate that rostral fluid shifts may depress semicircular canal activity, are briefly described. The results of this research suggest that the inner ear pressure and auditory threshold shift procedures could be used to assess individual differences among astronauts prior to space flight. Results from the terrestrial observations could be related to reported incidence/severity of motion sickness in space and used to evaluate the fluid shift theory of space motion sickness.

  16. The effects of food shortage during larval development on adult body size, body mass, physiology and developmental time in a tropical damselfly.

    PubMed

    Jiménez-Cortés, J Guillermo; Serrano-Meneses, Martín Alejandro; Córdoba-Aguilar, Alex

    2012-03-01

    Few studies have looked jointly at the effects of larval stressors on life history and physiology across metamorphosis, especially in tropical insects. Here we investigated how the variation of food availability during the larval stage of the tropical and territorial American rubyspot damselfly (Hetaerina americana) affects adult body size and body mass, and two physiological indicators of condition--phenoloxidase activity (an indicator of immune ability) and protein concentration. We also investigated whether larval developmental time is prolonged when food is scarce, an expected situation for tropical species whose larval time is less constrained, compared to temperate species. Second instar larvae were collected from their natural environments and reared in one of two diet regimes: (i) "rich" provided with five Artemia salina prey every day, and (ii) "poor" provided with two A. salina prey every day. In order to compare how distinct our treatments were from natural conditions, a second set of last-instar larvae were also collected and allowed to emerge. Only body size and phenoloxidase increased in the rich regime, possibly to prioritize investment on sexually selected traits (which increase mating opportunities), and immune ability, given pathogen pressure. The sexes did not differ in body size in relation to food regimes but they did differ in body mass and protein concentration; this can be explained on the basis of the energetically demanding territorial activities by males (for the case of body mass), and female allocation to egg production (for the case of protein). Finally, animals delayed larval development when food was scarce, which is coherent for tropical environments. These findings provide key insights in the role of food availability in a tropical species. PMID:22085821

  17. [Physiological basis of human mechanics and its application in the design of pressure suit].

    PubMed

    Jia, S G; Chen, J S

    1999-12-01

    Objective. To discuss the necessity that human mechanics and its physiological basis as applied to the research of human motion in many areas. Method. The motion performance of two aerospace [correction of areospace] pressure suit were studied. Human mechanics and its physiological basis was applied in the design of one suit only. Result. The result showed that good performance was obtained with the suit designed according to this principle which the stipulated actions couldn't be well performanced when wearing the suit not so designed. Conclusion. The research of the application of human mechanics and its physiological basis is necessary and it has better reality and is more scientific than applying biomechanics and robotics. PMID:12434811

  18. PHYSIOLOGICALLY BASED PHARMACOKINETIC MODEL FOR HUMAN EXPOSURES TO METHYL TERTIARY-BUTYL ETHER

    EPA Science Inventory

    Humans can be exposed by inhalation, ingestion, or dermal absorption to methyl tertiary-butyl ether (MTBE), an oxygenated fuel additive, from contaminated water sources. The purpose of this research was to develop a physiologically based pharmacokinetic model describing in human...

  19. Study of Physiological Responses to Acute Carbon Monoxide Exposure with a Human Patient Simulator

    ERIC Educational Resources Information Center

    Cesari, Whitney A.; Caruso, Dominique M.; Zyka, Enela L.; Schroff, Stuart T.; Evans, Charles H., Jr.; Hyatt, Jon-Philippe K.

    2006-01-01

    Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design,…

  20. Validation of Human Physiologically Based Pharmacokinetic Model for Vinyl Acetate Against Human Nasal Dosimetry Data

    SciTech Connect

    Hinderliter, Paul M.; Thrall, Karla D.; Corley, Rick A.; Bloemen, Louis J.; Bogdanffy, M S.

    2005-05-01

    Vinyl acetate has been shown to induce nasal lesions in rodents in inhalation bioassays. A physiologically based pharmacokinetic (PBPK) model for vinyl acetate has been used in human risk assessment, but previous in vivo validation was conducted only in rats. Controlled human exposures to vinyl acetate were conducted to provide validation data for the application of the model in humans. Five volunteers were exposed to 1, 5, and 10 ppm 13 C1 , 13 C2 vinyl acetate via inhalation. A probe inserted into thenasopharyngeal region sampled both 13 C1 , 13 C2 vinyl acetate and the major metabolite 13 C1 , 13 C2 acetaldehyde during rest and light exercise. Nasopharyngeal air concentrations were analyzed in real time by ion trap mass spectrometry (MS/MS). Experimental concentrations of both vinyl acetate and acetaldehyde were then compared to predicted concentrations calculated from the previously published human model. Model predictions of vinyl acetate nasal extraction compared favorably with measured values of vinyl acetate, as did predictions of nasopharyngeal acetaldehyde when compared to measured acetaldehyde. The results showed that the current PBPK model structure and parameterization are appropriate for vinyl acetate. These analyses were conducted from 1 to 10 ppm vinyl acetate, a range relevant to workplace exposure standards but which would not be expected to saturate vinyl acetate metabolism. Risk assessment based on this model further concluded that 24 h per day exposures up to 1 ppm do not present concern regarding cancer or non-cancer toxicity. Validation of the vinyl acetate human PBPK model provides support for these conclusions.

  1. Total body potassium in aging humans: A longitudinal study

    SciTech Connect

    Flynn, M.A.; Nolph, G.B.; Baker, A.S.; Martin, W.M.; Krause, G. )

    1989-10-01

    Total body potassium (TBK) data calculated from longitudinal measurements over 18 y of 40K by whole-body counting of 564 male and 61 female healthy humans in a 2-pi liquid scintillation counter show little change in females younger than 50 y compared with males of those ages. Males show less TBK from 41 y onward as they age, with most rapid rate of loss between 41 and 60 y. Females have a rapid loss of TBK when they are older than 60 y; the loss is at a greater rate than that of males. Percent total body fat calculated from total body weight and lean body mass (LBM) derived from TBK document greater adiposity in females at all ages except ages 51-60 y when females are similar to males in change in percent fat per year per centimeter.

  2. More-Realistic Digital Modeling of a Human Body

    NASA Technical Reports Server (NTRS)

    Rogge, Renee

    2010-01-01

    A MATLAB computer program has been written to enable improved (relative to an older program) modeling of a human body for purposes of designing space suits and other hardware with which an astronaut must interact. The older program implements a kinematic model based on traditional anthropometric measurements that do provide important volume and surface information. The present program generates a three-dimensional (3D) whole-body model from 3D body-scan data. The program utilizes thin-plate spline theory to reposition the model without need for additional scans.

  3. Matters of Taste: Bridging Molecular Physiology and the Humanities

    ERIC Educational Resources Information Center

    Rangachari, P. K.; Rangachari, Usha

    2015-01-01

    Taste perception was the focus of an undergraduate course in the health sciences that bridged the sciences and humanities. A problem-based learning approach was used to study the biological issues, whereas the cultural transmutations of these molecular mechanisms were explored using a variety of resources (novels, cookbooks, and films). Multiple…

  4. USE OF PHYSIOLOGICALLY BASED PHARMACOKINETIC (PBPK) MODELS TO QUANTIFY THE IMPACT OF HUMAN AGE AND INTERINDIVIDUAL DIFFERENCES IN PHYSIOLOGY AND BIOCHEMISTRY PERTINENT TO RISK (FINAL REPORT)

    EPA Science Inventory

    This final report, Use of Physiologically Based Pharmacokinetic (PBPK) Models to Quantify the Impact of Human Age and Interindividual Differences in Physiology and Biochemistry Pertinent to Risk Final R...

  5. Aptamer-Based Screens of Human Body Fluids for Biomarkers

    PubMed Central

    Albaba, Dania; Soomro, Sanam; Mohan, Chandra

    2015-01-01

    In recent years, aptamers have come to replace antibodies in high throughput multiplexed experiments. The aptamer-based biomarker screening technology, which kicked off in 2010, is capable of interrogating thousands of proteins in a very small sample volume. With this new technology, researchers hope to find clinically appropriate biomarkers for a myriad of illnesses by screening human body fluids. In this work, we have reviewed a total of eight studies utilizing aptamer-based biomarker screens of human body fluids, and have highlighted novel protein biomarkers discovered. PMID:27600232

  6. Biostereometric Data Processing In ERGODATA: Choice Of Human Body Models

    NASA Astrophysics Data System (ADS)

    Pineau, J. C.; Mollard, R.; Sauvignon, M.; Amphoux, M.

    1983-07-01

    The definition of human body models was elaborated with anthropometric data from ERGODATA. The first model reduces the human body into a series of points and lines. The second model is well adapted to represent volumes of each segmentary element. The third is an original model built from the conventional anatomical points. Each segment is defined in space by a tri-angular plane located with its 3-D coordinates. This new model can answer all the processing possibilities in the field of computer-aided design (C.A.D.) in ergonomy but also biomechanics and orthopaedics.

  7. Analysis of Human Body Bipedal Stability for Neuromotor Disabilities

    NASA Astrophysics Data System (ADS)

    Baritz, Mihaela; Cristea, Luciana; Rogozea, Liliana; Cotoros, Diana; Repanovici, Angela

    2009-04-01

    The analysis of different biomechanical aspects of balance and equilibrium is presented in the first part of the paper. We analyzed the posture, balance and stability of human body for a normal person and for a person with loco-motor or neuro-motor disabilities (in the second part). In the third part of the paper we presented the methodology and the experimental setup used to record the human body behavior in postural stability for persons with neuro-motors disabilities. The results and the conclusions are presented in the final part of the paper and also in the future work meant to establish the computer analysis for rehabilitation neuromotor disabilities.

  8. [An instrument for estimating human body composition using impedance measurement].

    PubMed

    Yin, J; Peng, C

    1997-03-01

    According to the impedance feature of biological tissue, the instrument was designed at 1, 5, 10, 50, 100kHz to measure human impedance, and then to calculate human FAT, FFM, FAT%, TBW, ECW, ICW and so on. A 8031 singlechip microprocessor contacuting used as a control center in the instrument. The part of electric circuit contacuting human body in the instrument was unreally earthing. The instrument was safty, effective, repeatable, and easily manpulative. Prelimintary clinical experiment showed the results measured with the instrument could effectively reflect practical, status of human composition. PMID:9647623

  9. Prediction of human core body temperature using non-invasive measurement methods

    NASA Astrophysics Data System (ADS)

    Niedermann, Reto; Wyss, Eva; Annaheim, Simon; Psikuta, Agnes; Davey, Sarah; Rossi, René Michel

    2014-01-01

    The measurement of core body temperature is an efficient method for monitoring heat stress amongst workers in hot conditions. However, invasive measurement of core body temperature (e.g. rectal, intestinal, oesophageal temperature) is impractical for such applications. Therefore, the aim of this study was to define relevant non-invasive measures to predict core body temperature under various conditions. We conducted two human subject studies with different experimental protocols, different environmental temperatures (10 °C, 30 °C) and different subjects. In both studies the same non-invasive measurement methods (skin temperature, skin heat flux, heart rate) were applied. A principle component analysis was conducted to extract independent factors, which were then used in a linear regression model. We identified six parameters (three skin temperatures, two skin heat fluxes and heart rate), which were included for the calculation of two factors. The predictive value of these factors for core body temperature was evaluated by a multiple regression analysis. The calculated root mean square deviation (rmsd) was in the range from 0.28 °C to 0.34 °C for all environmental conditions. These errors are similar to previous models using non-invasive measures to predict core body temperature. The results from this study illustrate that multiple physiological parameters (e.g. skin temperature and skin heat fluxes) are needed to predict core body temperature. In addition, the physiological measurements chosen in this study and the algorithm defined in this work are potentially applicable as real-time core body temperature monitoring to assess health risk in broad range of working conditions.

  10. Physiology and relevance of human adaptive thermogenesis response.

    PubMed

    Celi, Francesco S; Le, Trang N; Ni, Bin

    2015-05-01

    In homoeothermic organisms, the preservation of core temperature represents a primal function, and its costs in terms of energy expenditure can be considerable. In modern humans, the endogenous thermoregulation mechanisms have been replaced by clothing and environmental control, and the maintenance of thermoneutrality has been successfully achieved by manipulation of the micro- and macroenvironment. The rediscovery of the presence and activity of brown adipose tissue in adult humans has renewed the interest on adaptive thermogenesis (AT) as a means to facilitate weight loss and improve carbohydrate metabolism. The aim of this review is to describe the recent advancements in the study of this function, and to assess the potential and limitations of exploiting AT for environmental/behavioral, and pharmacological interventions. PMID:25869212

  11. Association between Human Body Composition and Periodontal Disease.

    PubMed

    Salekzamani, Yagoub; Shirmohammadi, Adileh; Rahbar, Mohammad; Shakouri, Seyed-Kazem; Nayebi, Farough

    2011-01-01

    Obesity in humans might increase the risk of periodontitis. The aim of the present study was to examine the relationship between body composition of males and their periodontal status. AS total of 150 males (aged 30-60) were selected: 31 were periodontally healthy, 45 had gingivitis, 39 had initial periodontitis, and 35 suffered from established periodontitis. BMI (body mass index), WC (waist circumference), and body composition parameters (consisting of body water, body fat, and skeletal muscle and bone mass) were measured. After adjusting for age, history of diabetes, smoking, physical activity status, and socioeconomic status, statistically significant correlations were found between periodontitis and BMI, WC, and body composition. There was only a statistically significant difference between the periodontal health and established periodontitis; that is, periodontal disease in mild forms (gingivitis) and initial periodontitis do not influence these variables (BMI, WC, and body composition parameters) and only the severe form of the disease influences the variables. These data suggest that there is a considerable association between severe forms of periodontal disease in males and their body composition, but this preliminary finding needs to be confirmed in more extensive studies. PMID:22111011

  12. Unique gel-coupled acoustic sensor array monitors human voice and physiology

    NASA Astrophysics Data System (ADS)

    Scanlon, Michael

    2002-11-01

    The health and performance of soldiers, firefighters, and other first responders in strenuous and hazardous environments can be continuously and remotely monitored with body-worn acoustic sensors. The Army Research Laboratory's gel-coupled acoustic physiological monitoring sensor has acoustic impedance properties similar to the skin that facilitate the transmission of body sounds into the sensor pad, yet significantly repel ambient airborne noises due to an impedance mismatch. Acoustic signal processing detects physiological events such as heartbeats, breaths, wheezes, coughs, blood pressure, activity, motion, and voice for communication and automatic speech recognition. Acoustic sensors can be in a helmet or in a strap around the neck, chest, and wrist. Although the physiological sounds have high SNR, the acoustic sensor also responds to motion-induced artifacts that sometimes obscure meaningful physiology. A noise-canceling sensor array configuration helps remove motion noise by using two acoustic sensors on the front sides of the neck and 2 additional acoustic sensors on each wrist. The motion noise detected on all 4 sensors will be dissimilar and out of phase, yet the physiology on all 4 sensors is covariant. Pulse wave transit time between neck and wrist will indicate systolic blood pressure. Data from a firefighter experiment will be presented.

  13. How dieting makes some fatter: from a perspective of human body composition autoregulation.

    PubMed

    Dulloo, Abdul G; Jacquet, Jean; Montani, Jean-Pierre

    2012-08-01

    Dieting makes you fat - the title of a book published in 1983 - embodies the notion that dieting to control body weight predisposes the individual to acquire even more body fat. While this notion is controversial, its debate underscores the large gap that exists in our understanding of basic physiological laws that govern the regulation of human body composition. A striking example is the key role attributed to adipokines as feedback signals between adipose tissue depletion and compensatory increases in food intake. Yet, the relative importance of fat depletion per se as a determinant of post-dieting hyperphagia is unknown. On the other hand, the question of whether the depletion of lean tissues can provide feedback signals on the hunger-appetite drive is rarely invoked, despite evidence that food intake during growth is dominated by the impetus for lean tissue deposition, amidst proposals for the existence of protein-static mechanisms for the regulation of growth and maintenance of lean body mass. In fact, a feedback loop between fat depletion and food intake cannot explain why human subjects recovering from starvation continue to overeat well after body fat has been restored to pre-starvation values, thereby contributing to 'fat overshooting'. In addressing the plausibility and mechanistic basis by which dieting may predispose to increased fatness, this paper integrates the results derived from re-analysis of classic longitudinal studies of human starvation and refeeding. These suggest that feedback signals from both fat and lean tissues contribute to recovering body weight through effects on energy intake and thermogenesis, and that a faster rate of fat recovery relative to lean tissue recovery is a central outcome of body composition autoregulation that drives fat overshooting. A main implication of these findings is that the risk of becoming fatter in response to dieting is greater in lean than in obese individuals. PMID:22475574

  14. Study of physiological responses to acute carbon monoxide exposure with a human patient simulator.

    PubMed

    Cesari, Whitney A; Caruso, Dominique M; Zyka, Enela L; Schroff, Stuart T; Evans, Charles H; Hyatt, Jon-Philippe K

    2006-12-01

    Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design, conduct, and present (orally and in written form) their project testing physiological adaptation to an extreme environment. This article is a student report on the physiological response to acute carbon monoxide exposure in a simulated healthy adult male and a coal miner and represents how 1) human patient simulators can be used in a nonclinical way for experiential hypothesis testing; 2) students can transition from traditional textbook learning to practical application of their knowledge; and 3) student-initiated group investigation drives critical thought. While the course instructors remain available for consultation throughout the project, the relatively unstructured framework of the assignment drives the students to create an experiment independently, troubleshoot problems, and interpret the results. The only stipulation of the project is that the students must generate an experiment that is physiologically realistic and that requires them to search out and incorporate appropriate data from primary scientific literature. In this context, the human patient simulator is a viable educational tool for teaching integrative physiology in a laboratory environment by bridging textual information with experiential investigation. PMID:17108253

  15. BodyMap: a human and mouse gene expression database.

    PubMed

    Hishiki, T; Kawamoto, S; Morishita, S; Okubo, K

    2000-01-01

    BodyMap is a human and mouse gene expression database that has been maintained since 1993. It is based on site-directed 3'-ESTs collected from non-biased cDNA libraries constructed at Osaka University and contains >270 000 sequences from 60 human and 38 mouse tissues. The site-directed nature of the sequence tags allows unequivocal grouping of tags representing the same transcript and provides abundance information for each transcript in different parts of the body. Our collection of ESTs was compared periodically with other public databases for cross referencing. The histological resolution of source tissues and unique cloning strategy that minimized cloning bias enabled BodyMap to support three unique mRNA based experiments in silico. First, the recurrence information for clones in each library provides a rough estimate of the mRNA composition of each source tissue. Second, a user can search the entire data set with nucleotide sequences or keywords to assess expression patterns of particular genes. Third, and most important, BodyMap allows a user to select genes that have a desired expression pattern in humans and mice. BodyMap is accessible through the WWW at http://bodymap.ims.u-tokyo.ac.jp PMID:10592203

  16. Convective and radiative heat transfer coefficients for individual human body segments.

    PubMed

    de Dear, R J; Arens, E; Hui, Z; Oguro, M

    1997-05-01

    Human thermal physiological and comfort models will soon be able to simulate both transient and spatial inhomogeneities in the thermal environment. With this increasing detail comes the need for anatomically specific convective and radiative heat transfer coefficients for the human body. The present study used an articulated thermal manikin with 16 body segments (head, chest, back, upper arms, forearms, hands, pelvis, upper legs, lower legs, feet) to generate radiative heat transfer coefficients as well as natural- and forced-mode convective coefficients. The tests were conducted across a range of wind speeds from still air to 5.0 m/s, representing atmospheric conditions typical of both indoors and outdoors. Both standing and seated postures were investigated, as were eight different wind azimuth angles. The radiative heat transfer coefficient measured for the whole-body was 4.5 W/m2 per K for both the seated and standing cases, closely matching the generally accepted whole-body value of 4.7 W/m2 per K. Similarly, the whole-body natural convection coefficient for the manikin fell within the mid-range of previously published values at 3.4 and 3.3 W/m2 per K when standing and seated respectively. In the forced convective regime, heat transfer coefficients were higher for hands, feet and peripheral limbs compared to the central torso region. Wind direction had little effect on convective heat transfers from individual body segments. A general-purpose forced convection equation suitable for application to both seated and standing postures indoors was hc = 10.3v0.6 for the whole-body. Similar equations were generated for individual body segments in both seated and standing postures. PMID:9195861

  17. Nuclear body formation and PML body remodeling by the human cytomegalovirus protein UL35

    SciTech Connect

    Salsman, Jayme; Wang Xueqi; Frappier, Lori

    2011-06-05

    The human cytomegalovirus (HCMV) UL35 gene encodes two proteins, UL35 and UL35a. Expression of UL35 in transfected cells results in the formation of UL35 nuclear bodies that associate with promyelocytic leukemia (PML) protein. PML forms the basis for PML nuclear bodies that are important for suppressing viral lytic gene expression. Given the important relationship between PML and viral infection, we have further investigated the association of UL35 with PML bodies. We demonstrate that UL35 bodies form independently of PML and subsequently recruit PML, Sp100 and Daxx. In contrast, UL35a did not form bodies; however, it could bind UL35 and inhibit the formation of UL35 bodies. The HCMV tegument protein pp71 promoted the formation of UL35 bodies and the cytoplasmic localization of UL35a. Similarly, UL35a shifted pp71 to the cytoplasm. These results indicate that the interplay between UL35, UL35a and pp71 affects their subcellular localization and likely their functions throughout infection.

  18. Intellectual property rights and detached human body parts.

    PubMed

    Pila, Justine

    2014-01-01

    This paper responds to an invitation by the editors to consider whether the intellectual property (IP) regime suggests an appropriate model for protecting interests in detached human body parts. It begins by outlining the extent of existing IP protection for body parts in Europe, and the relevant strengths and weaknesses of the patent system in that regard. It then considers two further species of IP right of less obvious relevance. The first are the statutory rights of ownership conferred by domestic UK law in respect of employee inventions, and the second are the economic and moral rights recognised by European and international law in respect of authorial works. In the argument made, both of these species of IP right may suggest more appropriate models of sui generis protection for detached human body parts than patent rights because of their capacity better to accommodate the relevant public and private interests in respect of the same. PMID:22844029

  19. Medical Sequencing at the extremes of Human Body Mass

    SciTech Connect

    Ahituv, Nadav; Kavaslar, Nihan; Schackwitz, Wendy; Ustaszewski,Anna; Martin, Joes; Hebert, Sybil; Doelle, Heather; Ersoy, Baran; Kryukov, Gregory; Schmidt, Steffen; Yosef, Nir; Ruppin, Eytan; Sharan,Roded; Vaisse, Christian; Sunyaev, Shamil; Dent, Robert; Cohen, Jonathan; McPherson, Ruth; Pennacchio, Len A.

    2006-09-01

    Body weight is a quantitative trait with significantheritability in humans. To identify potential genetic contributors tothis phenotype, we resequenced the coding exons and splice junctions of58 genes in 379 obese and 378 lean individuals. Our 96Mb survey included21 genes associated with monogenic forms of obesity in humans or mice, aswell as 37 genes that function in body weight-related pathways. We foundthat the monogenic obesity-associated gene group was enriched for rarenonsynonymous variants unique to the obese (n=46) versus lean (n=26)populations. Computational analysis further predicted a significantlygreater fraction of deleterious variants within the obese cohort.Consistent with the complex inheritance of body weight, we did notobserve obvious familial segregation in the majority of the 28 availablekindreds. Taken together, these data suggest that multiple rare alleleswith variable penetrance contribute to obesity in the population andprovide a deep medical sequencing based approach to detectthem.

  20. A low power wearable transceiver for human body communication.

    PubMed

    Huang, Jin; Chen, Lian-Kang; Zhang, Yuan-Ting

    2009-01-01

    This paper reports a low power transceiver designed for wearable medical healthcare system. Based on a novel energy-efficient wideband wireless communication scheme that uses human body as a transmission medium, the transceiver can achieve a maximum 15 Mbps data rate with total receiver sensitivity of -30 dBm. The chip measures only 0.56 mm(2) and was fabricated in the SMIC 0.18um 1P6M RF CMOS process. The RX consumes 5mW and TX dissipates 1mW with delivering power up to 10uW, which is suitable for the body area network short range application. Real-time medical information collecting through the human body is fully simulated. Architecture of the chip together with the detail characterizes from its wireless analog front-end are presented. PMID:19965236

  1. Young Scientists Explore the Human Body. Book 11 Primary Level.

    ERIC Educational Resources Information Center

    Penn, Linda

    Designed to present interesting facts about science and to heighten the curiosity of primary age students, this book contains activities about the natural world and numerous black and white illustrations. The activities specifically focus on the human body and encourage a positive self-concept. The theme of the first section is air--the breath of…

  2. Students' Conceptions about Energy and the Human Body

    ERIC Educational Resources Information Center

    Mann, Michael; Treagust, David F.

    2010-01-01

    Students' understanding of energy has been primarily within the domain of physics. This study sought to examine students' understanding of concepts relating to energy and the human body using pencil and paper questionnaires administered to 610 students in Years 8-12. From students' responses to the questionnaires, conceptual patterns were…

  3. Science Teachers' Drawings of What Is inside the Human Body

    ERIC Educational Resources Information Center

    Patrick, Patricia G.; Tunnicliffe, Sue Dale

    2010-01-01

    The purpose of this study was to report United States of America (USA) science teachers' understandings of the internal structures of the human body. The 71 science teachers who participated in this study attended a frog/pig, two-hour dissection workshop at the 2004 National Science Teachers Association (NSTA) conference in Atlanta, Georgia. The…

  4. The sri chakra as a symbol of the human body.

    PubMed

    Krishnakumar, P R

    1993-01-01

    Sri Chakra is the celebrated Yantra used in the worship of the primordial energy. The Chakra is conceived as a symbol of the human body. Some salient features of this symbolism are discussed in this article. An attempt has also been made to provide a short introduction to the Bhavanopanishad Prayogavidhi devised by Bhaskararaya, the doyen of Sri charka worshippers. PMID:22556608

  5. Of Human Bodies in Scientific Communication and Enculturation

    ERIC Educational Resources Information Center

    Hwang, SungWon; Roth, Wolff-Michael

    2008-01-01

    How do students become enculturated and come to enact culture in ways that are new to them? This study probes the dialectical processes of enculturation, the central aspect of which is the role of human bodies in communication. For students, as for any individual, culture exists in terms of action possibilities that presuppose their…

  6. [Mechanisms of natural variability at adaptation of human physiological systems to conditions of space flight].

    PubMed

    Larina, I M; Nosovskiĭ, A M; Grigor'ev, A I

    2012-01-01

    This article analyzes the physiological data using the principle of invariant relationships, to reveal the mechanisms of adaptive variability. It was used physical-chemical, biochemical, and hormonal blood parameters of cosmonauts who have committed short-term and long space flights. These results suggest that application of the methods of fractal geometry to quantitative estimates of homeostasis allows to allocate the processes depending on the increase/decrease of adaptive variability and fix the state of stability or instability of certain physiological regulatory subsystems, due to mobility and to reduce the level of stability which remains stable internal structure of relationships throughout the body. PMID:22679800

  7. Physiology and biochemistry of human subjects during entrapment.

    PubMed

    Agapiou, A; Mikedi, K; Karma, S; Giotaki, Z K; Kolostoumbis, D; Papageorgiou, C; Zorba, E; Spiliopoulou, C; Amann, A; Statheropoulos, M

    2013-03-01

    A classification of various categories of entrapped people under the ruins of collapsed buildings after earthquakes, technical failures or explosions is proposed. Type and degree of injury at the moment of building collapse and duration of entrapment are the two basic parameters in this classification. The aim is to provide sources and types of volatile organic compounds (VOCs) that can be used for establishing a new method for locating entrapped victims based on human chemical signatures. Potential target compounds, among others, are ammonia, acetone, isoprene, dimethylsulfide, dimethyldisulfide and trimethylamine. In this context, the possible neuroendocrine, metabolic and physical responses of potential victims during the different types of entrapment are correlated with the sources of VOCs such as expired air, urine, blood and sweat. The proposed classification scheme was developed as part of an integrated research project which investigates the use of combined audio, video and chemical methods for the early location of entrapped people under the ruins of collapsed buildings. PMID:23318246

  8. Physiological responses of juvenile rainbow trout to fasting and swimming activity: Effects on body composition and condition indices

    USGS Publications Warehouse

    Simpkins, D.G.; Hubert, W.A.; Del Rio, C.M.; Rule, D.C.

    2003-01-01

    The physiological traits that allow fish to survive periods of limited food resources are poorly understood. We assessed changes in proximate body composition, relative organ mass, blood metabolites, and relative weight (Wr) of sedentary and actively swimming (15 cm/s) juvenile rainbow trout (154-182 mm total length) over 147 d of fasting. Fasting caused measurable responses that were augmented when fish were swimming. Lipids and plasma triacylglycerides declined over time. Proteins were catabolized simultaneously with lipid reserves, but ammonia concentrations in plasma did not increase. The liver somatic index (LSI) did not change substantially over 105 d, suggesting that gluconeogenesis maintained blood glucose concentrations and hepatic glycogen reserves for a substantial period of fasting. The gut somatic index (GSI) and Wr declined linearly during fasting, but the LSI did not decline until after 105 d of fasting. Consequently, the use of different body condition indices could lead to different conclusions about the condition of juvenile rainbow trout. Swimming activity caused fish to have lower lipid and protein reserves than those of sedentary fish. No mortalities were observed among sedentary fish, but mortalities occurred among actively swimming fish after 97 d of fasting when 3.2% or less lipid remained in their bodies. Body condition indices did not account for differences in proximate body composition between sedentary and actively swimming fish and were relatively poor predictors of lipid content and risk of mortality. The probability of mortality was most accurately predicted by percent lipid content. Therefore, we suggest that fisheries scientists consider using percent lipid content when evaluating the physiological status and risk of mortality due to starvation among juvenile rainbow trout.

  9. Combined Volatolomics for Monitoring of Human Body Chemistry

    PubMed Central

    Broza, Yoav Y.; Zuri, Liat; Haick, Hossam

    2014-01-01

    Analysis of volatile organic compounds (VOCs) is a promising approach for non-invasive, fast and potentially inexpensive diagnostics. Here, we present a new methodology for profiling the body chemistry by using the volatile fraction of molecules in various body fluids. Using mass spectrometry and cross-reactive nanomaterial-based sensors array, we demonstrate that simultaneous VOC detection from breath and skin would provide complementary, non-correlated information of the body's volatile metabolites profile. Eventually with further wide population validation studies, such a methodology could provide more accurate monitoring of pathological changes compared to the information provided by a single body fluid. The qualitative and quantitative methods presented here offers a variety of options for novel mapping of the metabolic properties of complex organisms, including humans. PMID:24714440

  10. Combined Volatolomics for Monitoring of Human Body Chemistry

    NASA Astrophysics Data System (ADS)

    Broza, Yoav Y.; Zuri, Liat; Haick, Hossam

    2014-04-01

    Analysis of volatile organic compounds (VOCs) is a promising approach for non-invasive, fast and potentially inexpensive diagnostics. Here, we present a new methodology for profiling the body chemistry by using the volatile fraction of molecules in various body fluids. Using mass spectrometry and cross-reactive nanomaterial-based sensors array, we demonstrate that simultaneous VOC detection from breath and skin would provide complementary, non-correlated information of the body's volatile metabolites profile. Eventually with further wide population validation studies, such a methodology could provide more accurate monitoring of pathological changes compared to the information provided by a single body fluid. The qualitative and quantitative methods presented here offers a variety of options for novel mapping of the metabolic properties of complex organisms, including humans.

  11. Gamma resonance absorption. New approach in human body composition studies.

    PubMed

    Wielopolski, L; Vartsky, D; Pierson, R; Goldberg, M; Heymsfield, S; Yasumura, S; Melnychuk, S T; Sredniawski, J

    2000-05-01

    The main stream of body elemental analysis is based on the delayed, prompt, and inelastic neutron interactions with the main elements found in the human body, and subsequent analysis of the measured delayed or prompt gamma ray spectra. This methodology traditionally was, and still is, applied for whole body analysis and requires relatively high radiation doses. A new method, based on gamma nuclear resonance absorption (GNRA), is being established at Brookhaven National Laboratory as part of its body composition program. The method is element specific with a high tomographic spatial-resolution capability, at a small fraction of the radiation dose used in the current system. The new system, with its components and capabilities, is described below. PMID:10865747

  12. Upper Body Venous Compliance Exceeds Lower Body Venous Compliance in Humans

    NASA Technical Reports Server (NTRS)

    Watenpaugh, Donald E.

    1996-01-01

    Human venous compliance hypothetically decreases from upper to lower body as a mechanism for maintenance of the hydrostatic indifference level 'headward' in the body, near the heart. This maintains cardiac filling pressure, and thus cardiac output and cerebral perfusion, during orthostasis. This project entailed four steps. First, acute whole-body tilting was employed to alter human calf and neck venous volumes. Subjects were tilted on a tilt table equipped with a footplate as follows: 90 deg, 53 deg, 30 deg, 12 deg, O deg, -6 deg, -12 deg, -6 deg, O deg, 12 deg, 30 deg, 53 deg, and 90 deg. Tilt angles were held for 30 sec each, with 10 sec transitions between angles. Neck volume increased and calf volume decreased during head-down tilting, and the opposite occurred during head-up tilt. Second, I sought to cross-validate Katkov and Chestukhin's (1980) measurements of human leg and neck venous pressures during whole-body tilting, so that those data could be used with volume data from the present study to calculate calf and neck venous compliance (compliance = (Delta)volume/(Delta)pressure). Direct measurements of venous pressures during postural chances and whole-body tilting confirmed that the local changes in venous pressures seen by Katkov and Chestukhin (1980) are valid. The present data also confirmed that gravitational changes in calf venous pressure substantially exceed those changes in upper body venous pressure. Third, the volume and pressure data above were used to find that human neck venous compliance exceeds calf venous compliance by a factor of 6, thereby upholding the primary hypothesis. Also, calf and neck venous compliance correlated significantly with each other (r(exp 2) = 0.56). Fourth, I wished to determine whether human calf muscle activation during head-up tilt reduces calf venous compliance. Findings from tilting and from supine assessments of relaxed calf venous compliance were similar, indicating that tilt-induced muscle activation is

  13. Robot and Human Surface Operations on Solar System Bodies

    NASA Technical Reports Server (NTRS)

    Weisbin, C. R.; Easter, R.; Rodriguez, G.

    2001-01-01

    This paper presents a comparison of robot and human surface operations on solar system bodies. The topics include: 1) Long Range Vision of Surface Scenarios; 2) Human and Robots Complement Each Other; 3) Respective Human and Robot Strengths; 4) Need More In-Depth Quantitative Analysis; 5) Projected Study Objectives; 6) Analysis Process Summary; 7) Mission Scenarios Decompose into Primitive Tasks; 7) Features of the Projected Analysis Approach; and 8) The "Getting There Effect" is a Major Consideration. This paper is in viewgraph form.

  14. State of the body in disorders of diurnal physiological rhythms and long-term hypokinesia

    NASA Technical Reports Server (NTRS)

    Razin, S. N.; Rychko, A. V.

    1980-01-01

    In order to study the effects of hypokinesia and circadian rhythm restructuring on the morphological and functional status of the hypothalamo-hypophysic-adrenal system, young male Wistar rats were placed in small cages for varying periods. The animals were decapitated and preparations were made from sections of the brain and adrenals and numerous destructive changes were noted in the investigated regions of the brain, indicating that the condition of these areas is directly affected by disruption of established rhythms in physiological processes.

  15. Matters of taste: bridging molecular physiology and the humanities.

    PubMed

    Rangachari, P K; Rangachari, Usha

    2015-12-01

    Taste perception was the focus of an undergraduate course in the health sciences that bridged the sciences and humanities. A problem-based learning approach was used to study the biological issues, whereas the cultural transmutations of these molecular mechanisms were explored using a variety of resources (novels, cookbooks, and films). Multiple evaluation procedures were used: problem summaries and problem-solving exercises (tripartite problem-solving exercise) for the problem-based learning component and group tasks and individual exercises for the cultural issues. Self-selected groups chose specific tasks from a prescribed list of options (setting up a journal in molecular gastronomy, developing an electronic tongue, designing a restaurant for synesthetes, organizing a farmers' market, marketing a culinary tour, framing hedonic scales, exploring changing tastes through works of art or recipe books, and crafting beers for space travel). Individual tasks were selected from a menu of options (book reviews, film reviews, conversations, creative writing, and oral exams). A few guest lecturers (wine making, cultural anthropology, film analysis, and nutritional epidemiology) added more flavor. The course was rated highly for its learning value (8.5 ± 1.2, n = 62) and helped students relate biological mechanisms to cultural issues (9.0 ± 0.9, n = 62). PMID:26628651

  16. Physiologically-based pharmacokinetic (PBPK) models in human exposure assessment

    SciTech Connect

    Krishnan, K.

    1995-12-31

    The potential dose received by an individual during defined exposure situations can be determined using personal dosimeters or estimated by combining information on exposure scenarios with the environmental concentration (C.) of chemicals. With the latter approach, not only the potential dose but also the internal dose (i.e., amount of chemical that has been absorbed and available for interaction with receptors) and biologically-effective dose (i.e., amount of chemical that actually reaches the cellular sites where interaction with macromolecules occur) can be estimated if C. is provided as an input to PBPK models. These models are mathematical representations of the interrelationships among the critical determinants of the absorption, distribution, metabolism and excretion of chemicals in biota. Since the compartments in this model correspond to biologically relevant tissues or tissue groups, the amount of chemical reaching specific target organ(s) can be estimated. Further, the PBPK models permit the use of biological monitoring data such as urinary levels of metabolites, hemoglobin adduct levels, and alveolar air concentrations, to reconstruct the exposure levels and scenarios for specific subgroups of populations. These models are also useful in providing estimates of target tissue dose in humans simultaneously exposed to chemicals in various media (air, water, soil, food) by different routes (oral, dermal, inhalation). Several examples of exposure assessment for volatile organic chemicals using PBPK models for mammals will be presented, and the strategies for development of these models for other classes of chemicals highlighted.

  17. Synchronization Analysis of Language and Physiology in Human Dyads.

    PubMed

    Orsucci, Franco F; Musmeci, Nicolò; Aas, Benjamin; Schiepek, Günter; Reda, Mario A; Canestri, Luca; Giuliani, Alessandro; de Felice, Giulio

    2016-04-01

    We studied the synchronization dynamics of a therapist and patient during a psychotherapy session. This investigation was developed in order to explore a new possible perspective and methodology for studying the expression of emotions. More specifically, literature concerning synchronization of in-session non-verbal variables emphasises its positive correlation with empathy and therapeutic outcomes. We compared the dynamics of galvanic skin response (GSR) and linguistic prosody, chosen as indicators of emotional expression in different domains. We studied their synchronization through complementary methodologies: Recurrence Quantification Analysis (RQA) and Principal Component Analysis (PCA), Markov Transition Matrix (MTM) and Cross-Recurrence Quantification Analysis (CRQA). We investigated the nonlinearity of GSR in terms of self-similarity and power-law, as emerged in autocorrelation functions and signal variations. We considered time-lagged correlations as a measure of dynamical systems' memory. This article concludes by highlighting the importance of a deeper study of all variables related to the psychotherapeutic process and their synchronization in order to extend our knowledge of general human dynamics. PMID:27033132

  18. Human colorectal mucosal microbiota correlates with its host niche physiology revealed by endomicroscopy

    PubMed Central

    Wang, Ai-Hua; Li, Ming; Li, Chang-Qing; Kou, Guan-Jun; Zuo, Xiu-Li; Li, Yan-Qing

    2016-01-01

    The human gut microbiota plays a pivotal role in the maintenance of health, but how the microbiota interacts with the host at the colorectal mucosa is poorly understood. We proposed that confocal laser endomicroscopy (CLE) might help to untangle this relationship by providing in vivo physiological information of the mucosa. We used CLE to evaluate the in vivo physiology of human colorectal mucosa, and the mucosal microbiota was quantified using 16 s rDNA pyrosequencing. The human mucosal microbiota agglomerated to three major clusters dominated by Prevotella, Bacteroides and Lactococcus. The mucosal microbiota clusters did not significantly correlate with the disease status or biopsy sites but closely correlated with the mucosal niche physiology, which was non-invasively revealed by CLE. Inflammation tilted two subnetworks within the mucosal microbiota. Infiltration of inflammatory cells significantly correlated with multiple components in the predicted metagenome, such as the VirD2 component of the type IV secretory pathway. Our data suggest that a close correlation exists between the mucosal microbiota and the colorectal mucosal physiology, and CLE is a clinically available tool that can be used to facilitate the study of the in vivo correlation between colorectal mucosal physiology and the mucosal microbiota. PMID:26916597

  19. Thermal imaging to detect physiological indicators of stress in humans

    NASA Astrophysics Data System (ADS)

    Cross, Carl B.; Skipper, Julie A.; Petkie, Douglas T.

    2013-05-01

    Real-time, stand-off sensing of human subjects to detect emotional state would be valuable in many defense, security and medical scenarios. We are developing a multimodal sensor platform that incorporates high-resolution electro-optical and mid-wave infrared (MWIR) cameras and a millimeter-wave radar system to identify individuals who are psychologically stressed. Recent experiments have aimed to: 1) assess responses to physical versus psychological stressors; 2) examine the impact of topical skin products on thermal signatures; and 3) evaluate the fidelity of vital signs extracted from thermal imagery and radar signatures. Registered image and sensor data were collected as subjects (n=32) performed mental and physical tasks. In each image, the face was segmented into 29 non-overlapping segments based on fiducial points automatically output by our facial feature tracker. Image features were defined that facilitated discrimination between psychological and physical stress states. To test the ability to intentionally mask thermal responses indicative of anxiety or fear, subjects applied one of four topical skin products to one half of their face before performing tasks. Finally, we evaluated the performance of two non-contact techniques to detect respiration and heart rate: chest displacement extracted from the radar signal and temperature fluctuations at the nose tip and regions near superficial arteries to detect respiration and heart rates, respectively, extracted from the MWIR imagery. Our results are very satisfactory: classification of physical versus psychological stressors is repeatedly greater than 90%, thermal masking was almost always ineffective, and accurate heart and respiration rates are detectable in both thermal and radar signatures.

  20. Effects of MDMA on body temperature in humans

    PubMed Central

    Liechti, Matthias E

    2014-01-01

    Hyperthermia is a severe complication associated with the recreational use of 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy). In this review, the clinical laboratory studies that tested the effects of MDMA on body temperature are summarized. The mechanisms that underlie the hyperthermic effects of MDMA in humans and treatment of severe hyperthermia are presented. The data show that MDMA produces an acute and dose-dependent rise in core body temperature in healthy subjects. The increase in body temperature is in the range of 0.2-0.8°C and does not result in hyperpyrexia (>40°C) in a controlled laboratory setting. However, moderately hyperthermic body temperatures >38.0°C occur frequently at higher doses, even in the absence of physical activity and at room temperature. MDMA primarily releases serotonin and norepinephrine. Mechanistic clinical studies indicate that the MDMA-induced elevations in body temperature in humans partially depend on the MDMA-induced release of norepinephrine and involve enhanced metabolic heat generation and cutaneous vasoconstriction, resulting in impaired heat dissipation. The mediating role of serotonin is unclear. The management of sympathomimetic toxicity and associated hyperthermia mainly includes sedation with benzodiazepines and intravenous fluid replacement. Severe hyperthermia should primarily be treated with additional cooling and mechanical ventilation.

  1. Human body scents: do they influence our behavior?

    PubMed

    Mildner, Sophie; Buchbauer, Gerhard

    2013-11-01

    Pheromonal communication in the animal world has been of great research interest for a long time. While extraordinary discoveries in this field have been made, the importance of the human sense of smell was of far lower interest. Humans are seen as poor smellers and therefore research about human olfaction remains quite sparse compared with other animals. Nevertheless amazing achievements have been made during the past 15 years. This is a collection of available data on this topic and a controversial discussion on the role of putative human pheromones in our modem way of living. While the focus was definitely put on behavioral changes evoked by putative human pheromones this article also includes other important aspects such as the possible existence of a human vomeronasal organ. If pheromones do have an influence on human behavior there has to be a receptor organ. How are human body scents secreted and turned into odorous substances? And how can con-specifics detect those very odors and transmit them to the brain? Apart from that the most likely candidates for human pheromones are taken on account and their impact on human behavior is shown in various detail. PMID:24427964

  2. Physiological responses to prolonged bed rest and fluid immersion in humans

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.

    1984-01-01

    For many centuries, physicians have used prolonged rest in bed and immersion in water in the treatment of ailments and disease. Both treatments have positive remedial effects. However, adverse physiological responses become evident when patients return to their normal daily activities. The present investigation is concerned with an analysis of the physiological changes during bed rest and the effects produced by water immersion. It is found that abrupt changes in body position related to bed rest cause acute changes in fluid compartment volumes. Attention is given to fluid shifts and body composition, renal function and diuresis, calcium and phosphorus metabolism, and orthostatic tolerance. In a discussion of water immersion, fluid shifts are considered along with cardiovascular-respiratory responses, renal function, and natriuretic and diuretic factors.

  3. Coursera's Introductory Human Physiology Course: Factors That Characterize Successful Completion of a MOOC

    ERIC Educational Resources Information Center

    Engle, Deborah; Mankoff, Chris; Carbrey, Jennifer

    2015-01-01

    Since Massive Open Online Courses (MOOCs) are accessible by anyone in the world at no cost, they have large enrollments that are conducive to educational research. This study examines students in the Coursera MOOC, Introductory Human Physiology. Of the 33,378 students who accessed the course, around 15,000 students responded to items on the…

  4. Understanding Protein Synthesis: A Role-Play Approach in Large Undergraduate Human Anatomy and Physiology Classes

    ERIC Educational Resources Information Center

    Sturges, Diana; Maurer, Trent W.; Cole, Oladipo

    2009-01-01

    This study investigated the effectiveness of role play in a large undergraduate science class. The targeted population consisted of 298 students enrolled in 2 sections of an undergraduate Human Anatomy and Physiology course taught by the same instructor. The section engaged in the role-play activity served as the study group, whereas the section…

  5. Physiological responses to prolonged bed rest in humans: A compendium of research, 1981-1988

    NASA Technical Reports Server (NTRS)

    Luu, Phuong B.; Ortiz, Vanessa; Barnes, Paul R.; Greenleaf, John E.

    1990-01-01

    Clinical observations and results form more basic studies that help to elucidate the physiological mechanisms of the adaptation of humans to prolonged bed rest. If the authors' abstract or summary was appropriate, it was included. In some cases a more detailed synopsis was provided under the subheadings of purpose, methods, results, and conclusions.

  6. Population Physiologically-Based Pharmacokinetic Modeling for the Human Lactational Transfer of PCB 153 with Consideration of Worldwide Human Biomonitoring Results

    SciTech Connect

    Redding, Laurel E.; Sohn, Michael D.; McKone, Thomas E.; Wang, Shu-Li; Hsieh, Dennis P. H.; Yang, Raymond S. H.

    2008-03-01

    We developed a physiologically based pharmacokinetic model of PCB 153 in women, and predict its transfer via lactation to infants. The model is the first human, population-scale lactational model for PCB 153. Data in the literature provided estimates for model development and for performance assessment. Physiological parameters were taken from a cohort in Taiwan and from reference values in the literature. We estimated partition coefficients based on chemical structure and the lipid content in various body tissues. Using exposure data in Japan, we predicted acquired body burden of PCB 153 at an average childbearing age of 25 years and compare predictions to measurements from studies in multiple countries. Forward-model predictions agree well with human biomonitoring measurements, as represented by summary statistics and uncertainty estimates. The model successfully describes the range of possible PCB 153 dispositions in maternal milk, suggesting a promising option for back estimating doses for various populations. One example of reverse dosimetry modeling was attempted using our PBPK model for possible exposure scenarios in Canadian Inuits who had the highest level of PCB 153 in their milk in the world.

  7. Forward dynamics simulation of human body under tilting perturbations

    NASA Astrophysics Data System (ADS)

    Naderi, D.; Pasha Zanoosi, A. A.; Sadeghi-Mehr, M.

    2012-02-01

    Human body uses different strategies to maintain its stability and these strategies vary from fixed-foot strategies to strategies which foot is moved in order to increase the support base. Tilting movement of foot is one type of the perturbations usually is exposed to human body. In the presence of such perturbations human body must employ appropriate reactions to prevent threats like falling. But it is not clear that how human body maintains its stability by central nervous system (CNS). At present study it is tried that by presenting a musculoskeletal model of human lower extremity with four links, three degrees of freedom (DOF) and eight skeletal muscles, the level of muscle activations causes the maintenance of stability, be investigated. Using forward dynamics solution, leads to a more general problem, rather than inverse dynamics. Hence, forward dynamics solution by forward optimization has been used for solving this highly nonlinear problem. To this end, first the system's equations of motion has been derived using lagrangian dynamics. Eight Hill-type muscles as actuators of the system were modeled. Because determination of muscle forces considering their number is an undetermined problem, optimization of an appropriate goal function should be practiced. For optimization problem, the characteristics of genetic algorithms as a method based on direct search, and the direct collocation method, has been profited. Also by considering requirements of problem, some constraints such as conservation of model stability are entered into optimization procedure. Finally to investigate validation of model, the results from optimization and experimental data are compared and good agreements are obtained.

  8. Development of a secure body area network for a wearable physiological monitoring system using a PSoC processor.

    PubMed

    Sriraam, N; Swathy, S; Vijayalakshmi, S

    2012-01-01

    Wearable physiological monitoring systems have gained popularity in the recent years due to their ability to continuously monitor physiological signals, thereby making them suitable for home-healthcare applications. The electrocardiogram (ECG), phonocardiogram (PCG) and photoplethysmogram (PPG) signals have been studied and it has been observed that there is a correlation between the three signals. This paper proposes the development of a secure body area network (BAN), for a wearable physiological monitoring system. The BAN is composed of three nodes, for ECG, PPG and PCG signals. The peak-peak distances of these signals are calculated first, in the coordinator of BAN. The coordinator is designed in such a manner that signals from it are transmitted to a monitoring station, only if the difference between the peak-peak distances of both ECG-PPG signals and ECG-PCG signals fall below a threshold. The entire operation of the coordinator is implemented using a real-time processor, Cypress(™) Programmable System on Chip (PSoC). PMID:22188576

  9. BodyWindows: enhancing a mannequin with projective augmented reality for exploring anatomy, physiology and medical procedures.

    PubMed

    Samosky, Joseph T; Wang, Bo; Nelson, Douglas A; Bregman, Russell; Hosmer, Andrew; Weaver, Robert A

    2012-01-01

    Augmented reality offers the potential to radically extend and enhance the capabilities of physical medical simulators such as full-body mannequin trainers. We have developed a system that transforms the surface of a mannequin simulator into both a display screen and an input device. The BodyWindows system enables a user to open, size, and reposition multiple viewports onto the simulator body. We demonstrate a dynamic viewport that displays a beating heart. Similar viewports could be used to display real-time physiological responses to interventions the user applies to the mannequin, such as injection of a simulated drug. Viewport windows can be overlapping and show anatomy at different depths, creating the illusion of "cutting" multiple windows into the body to reveal structures at different depths from the surface. The developed low-cost interface employees an IR light pen and the Nintendo Wiimote. We also report experiments using the Microsoft Kinect computer vision sensor to provide a completely hand-gesture based interface. PMID:22357032

  10. Bodily ownership modulation in defensive responses: physiological evidence in brain-damaged patients with pathological embodiment of other's body parts.

    PubMed

    Fossataro, C; Gindri, P; Mezzanato, T; Pia, L; Garbarini, F

    2016-01-01

    Do conscious beliefs about the body affect defensive mechanisms within the body? To answer this question we took advantage from a monothematic delusion of bodily ownership, in which brain-damaged patients misidentify alien limbs as their own. We investigated whether the delusional belief that an alien hand is their own hand modulates a subcortical defensive response, such as the hand-blink reflex. The blink, dramatically increases when the threated hand is inside the defensive peripersonal-space of the face. In our between-subjects design, including patients and controls, the threat was brought near the face either by the own hand or by another person's hand. Our results show an ownership-dependent modulation of the defensive response. In controls, as well as in the patients' intact-side, the response enhancement is significantly greater when the threat was brought near the face by the own than by the alien hand. Crucially, in the patients' affected-side (where the pathological embodiment occurs), the alien (embodied) hand elicited a response enhancement comparable to that found when the threat is brought near the face by the real hand. These findings suggest the existence of a mutual interaction between our conscious beliefs about the body and the physiological mechanisms within the body. PMID:27292285

  11. Physiological response of wild rainbow trout to angling: Impact of angling duration, fish size, body condition, and temperature

    USGS Publications Warehouse

    Meka, J.M.; McCormick, S.D.

    2005-01-01

    This study evaluated the immediate physiological response of wild rainbow trout to catch-and-release angling in the Alagnak River, southwest Alaska. Information was recorded on individual rainbow trout (n = 415) captured by angling including landing time and the time required to remove hooks (angling duration), the time to anesthetize fish in clove oil and withdraw blood, fish length and weight, and water temperature at capture locations. Plasma cortisol, glucose, ions (sodium, potassium, chloride), and lactate were analyzed to determine the effects of angling duration, fish size, body condition, and temperature. Levels of plasma ions did not change significantly during the observed physiological response and levels of plasma glucose were sometimes influenced by length (2000, 2001), body condition (2001), or temperature (2001). Levels of plasma cortisol and lactate in extended capture fish (angling duration greater than 2 min) were significantly higher than levels in rapid capture fish (angling duration less than 2 min). Rapid capture fish were significantly smaller than extended capture fish, reflecting that fish size influenced landing and handling times. Fish size was related to cortisol and lactate in 2002, which corresponded to the year when larger fish were captured and there were longer landing times. Body condition (i.e., weight/length regression residuals index), was significantly related to lactate in 2000 and 2001. Water temperatures were higher in 2001 (mean temperature ± S.E., 13 ± 2oC) than in 2002 (10 ± 2oC), and fish captured in 2001 had significantly higher cortisol and lactate concentrations than fish captured in 2002. The pattern of increase in plasma cortisol and lactate was due to the amount of time fish were angled, and the upper limit of the response was due to water temperature. The results of this study indicate the importance of minimizing the duration of angling in order to reduce the sublethal physiological disturbances in wild

  12. Yes, there is a medial nucleus of the trapezoid body in humans

    PubMed Central

    Kulesza, Randy J.; Grothe, Benedikt

    2015-01-01

    The medial nucleus of the trapezoid body (MNTB) is a collection of brainstem neurons that function within the ascending auditory pathway. MNTB neurons are associated with a number of anatomical and physiological specializations which make these cells especially well-equipped to provide extremely fast and precise glycinergic inhibition to its target neurons in the superior olivary complex and ventral nucleus of the lateral lemniscus. The inhibitory influence of MNTB neurons plays essentials roles in the localization of sound sources and encoding temporal features of complex sounds. The morphology, afferent and efferent connections and physiological response properties of MNTB neurons have been well-characterized in a number of laboratory rodents and some carnivores. Furthermore, the MNTB has been positively identified in all mammals examined, ranging from opossum and mice to chimpanzees. From the early 1970s through 2009, a number of studies denied the existence of the MNTB in humans and consequentially, the existence of this nucleus in the human brain has been debated for nearly 50 years. The absence of the MNTB from the human brain would negate current principles of sound localization and would require a number of novel adaptations, entirely unique to humans. However, a number of recent studies of human post-mortem tissue have provided evidence supporting the existence of the MNTB in humans. It therefore seems timely to review the structure and function of the MNTB, critically review the literature which led to the denial of the human MNTB and then review recent investigations supporting the existence of the MNTB in the human brain. PMID:25873865

  13. Anger in brain and body: the neural and physiological perturbation of decision-making by emotion.

    PubMed

    Garfinkel, Sarah N; Zorab, Emma; Navaratnam, Nakulan; Engels, Miriam; Mallorquí-Bagué, Núria; Minati, Ludovico; Dowell, Nicholas G; Brosschot, Jos F; Thayer, Julian F; Critchley, Hugo D

    2016-01-01

    Emotion and cognition are dynamically coupled to bodily arousal: the induction of anger, even unconsciously, can reprioritise neural and physiological resources toward action states that bias cognitive processes. Here we examine behavioural, neural and bodily effects of covert anger processing and its influence on cognition, indexed by lexical decision-making. While recording beat-to-beat blood pressure, the words ANGER or RELAX were presented subliminally just prior to rapid word/non-word reaction-time judgements of letter-strings. Subliminal ANGER primes delayed the time taken to reach rapid lexical decisions, relative to RELAX primes. However, individuals with high trait anger were speeded up by subliminal anger primes. ANGER primes increased systolic blood pressure and the magnitude of this increase predicted reaction time prolongation. Within the brain, ANGER trials evoked an enhancement of activity within dorsal pons and an attenuation of activity within visual occipitotemporal and attentional parietal cortices. Activity within periaqueductal grey matter, occipital and parietal regions increased linearly with evoked blood pressure changes, indicating neural substrates through which covert anger impairs semantic decisions, putatively through its expression as visceral arousal. The behavioural and physiological impact of anger states compromises the efficiency of cognitive processing through action-ready changes in autonomic response that skew regional neural activity. PMID:26253525

  14. Reduction of a Whole-Body Physiologically Based Pharmacokinetic Model to Stabilise the Bayesian Analysis of Clinical Data.

    PubMed

    Wendling, Thierry; Tsamandouras, Nikolaos; Dumitras, Swati; Pigeolet, Etienne; Ogungbenro, Kayode; Aarons, Leon

    2016-01-01

    Whole-body physiologically based pharmacokinetic (PBPK) models are increasingly used in drug development for their ability to predict drug concentrations in clinically relevant tissues and to extrapolate across species, experimental conditions and sub-populations. A whole-body PBPK model can be fitted to clinical data using a Bayesian population approach. However, the analysis might be time consuming and numerically unstable if prior information on the model parameters is too vague given the complexity of the system. We suggest an approach where (i) a whole-body PBPK model is formally reduced using a Bayesian proper lumping method to retain the mechanistic interpretation of the system and account for parameter uncertainty, (ii) the simplified model is fitted to clinical data using Markov Chain Monte Carlo techniques and (iii) the optimised reduced PBPK model is used for extrapolation. A previously developed 16-compartment whole-body PBPK model for mavoglurant was reduced to 7 compartments while preserving plasma concentration-time profiles (median and variance) and giving emphasis to the brain (target site) and the liver (elimination site). The reduced model was numerically more stable than the whole-body model for the Bayesian analysis of mavoglurant pharmacokinetic data in healthy adult volunteers. Finally, the reduced yet mechanistic model could easily be scaled from adults to children and predict mavoglurant pharmacokinetics in children aged from 3 to 11 years with similar performance compared with the whole-body model. This study is a first example of the practicality of formal reduction of complex mechanistic models for Bayesian inference in drug development. PMID:26538125

  15. On the dynamics of a human body model.

    NASA Technical Reports Server (NTRS)

    Huston, R. L.; Passerello, C. E.

    1971-01-01

    Equations of motion for a model of the human body are developed. Basically, the model consists of an elliptical cylinder representing the torso, together with a system of frustrums of elliptical cones representing the limbs. They are connected to the main body and each other by hinges and ball and socket joints. Vector, tensor, and matrix methods provide a systematic organization of the geometry. The equations of motion are developed from the principles of classical mechanics. The solution of these equations then provide the displacement and rotation of the main body when the external forces and relative limb motions are specified. Three simple example motions are studied to illustrate the method. The first is an analysis and comparison of simple lifting on the earth and the moon. The second is an elementary approach to underwater swimming, including both viscous and inertia effects. The third is an analysis of kicking motion and its effect upon a vertically suspended man such as a parachutist.

  16. Towards Whole-Body Fluorescence Imaging in Humans

    PubMed Central

    Piper, Sophie K.; Habermehl, Christina; Schmitz, Christoph H.; Kuebler, Wolfgang M.; Obrig, Hellmuth; Steinbrink, Jens; Mehnert, Jan

    2013-01-01

    Dynamic near-infrared fluorescence (DNIF) whole-body imaging of small animals has become a popular tool in experimental biomedical research. In humans, however, the field of view has been limited to body parts, such as rheumatoid hands, diabetic feet or sentinel lymph nodes. Here we present a new whole-body DNIF-system suitable for adult subjects. We explored whether this system (i) allows dynamic whole-body fluorescence imaging and (ii) can detect modulations in skin perfusion. The non-specific fluorescent probe indocyanine green (ICG) was injected intravenously into two subjects, and fluorescence images were obtained at 5 Hz. The in- and out-flow kinetics of ICG have been shown to correlate with tissue perfusion. To validate the system, skin perfusion was modulated by warming and cooling distinct areas on the chest and the abdomen. Movies of fluorescence images show a bolus passage first in the face, then in the chest, abdomen and finally in the periphery (∼10, 15, 20 and 30 seconds, respectively). When skin perfusion is augmented by warming, bolus arrives about 5 seconds earlier than when the skin is cooled and perfusion decreased. Calculating bolus arrival times and spatial fitting of basis time courses extracted from different regions of interest allowed a mapping of local differences in subcutaneous skin perfusion. This experiment is the first to demonstrate the feasibility of whole-body dynamic fluorescence imaging in humans. Since the whole-body approach demonstrates sensitivity to circumscribed alterations in skinperfusion, it may be used to target autonomous changes in polyneuropathy and to screen for peripheral vascular diseases. PMID:24391820

  17. Physiological evidence for a human-induced landscape of fear in brown bears (Ursus arctos).

    PubMed

    Støen, Ole-Gunnar; Ordiz, Andres; Evans, Alina L; Laske, Timothy G; Kindberg, Jonas; Fröbert, Ole; Swenson, Jon E; Arnemo, Jon M

    2015-12-01

    Human persecution is a major cause of mortality for large carnivores. Consequently, large carnivores avoid humans, but may use human-dominated landscapes by being nocturnal and elusive. Behavioral studies indicate that certain ecological systems are "landscapes of fear", driven by antipredator behavior. Because behavior and physiology are closely interrelated, physiological assessments may provide insight into the behavioral response of large carnivores to human activity. To elucidate changes in brown bears' (Ursus arctos) behavior associated with human activity, we evaluated stress as changes in heart rate (HR) and heart rate variability (HRV) in 12 GPS-collared, free-ranging bears, 7 males and 5 females, 3-11 years old, using cardiac-monitoring devices. We applied generalized linear regression models with HR and HRV as response variables and chest activity, time of day, season, distance traveled, and distance to human settlements from GPS positions recorded every 30 min as potential explanatory variables. Bears exhibited lower HRV, an indication of stress, when they were close to human settlements and especially during the berry season, when humans were more often in the forest, picking berries and hunting. Our findings provide evidence of a human-induced landscape of fear in this hunted population of brown bears. PMID:26476156

  18. Medical Sequencing at the Extremes of Human Body Mass

    PubMed Central

    Ahituv, Nadav ; Kavaslar, Nihan ; Schackwitz, Wendy ; Ustaszewska, Anna ; Martin, Joel ; Hébert, Sybil ; Doelle, Heather ; Ersoy, Baran ; Kryukov, Gregory ; Schmidt, Steffen ; Yosef, Nir ; Ruppin, Eytan ; Sharan, Roded ; Vaisse, Christian ; Sunyaev, Shamil ; Dent, Robert ; Cohen, Jonathan ; McPherson, Ruth ; Pennacchio, Len A. 

    2007-01-01

    Body weight is a quantitative trait with significant heritability in humans. To identify potential genetic contributors to this phenotype, we resequenced the coding exons and splice junctions of 58 genes in 379 obese and 378 lean individuals. Our 96-Mb survey included 21 genes associated with monogenic forms of obesity in humans or mice, as well as 37 genes that function in body weight–related pathways. We found that the monogenic obesity–associated gene group was enriched for rare nonsynonymous variants unique to the obese population compared with the lean population. In addition, computational analysis predicted a greater fraction of deleterious variants within the obese cohort. Together, these data suggest that multiple rare alleles contribute to obesity in the population and provide a medical sequencing-based approach to detect them. PMID:17357083

  19. Single-friction-surface triboelectric generator with human body conduit

    SciTech Connect

    Meng, Bo; Cheng, Xiaoliang; Zhang, Xiaosheng; Han, Mengdi; Liu, Wen; Zhang, Haixia

    2014-03-10

    We present a transparent single-friction-surface triboelectric generator (STEG) employing human body as the conduit, making the applications of STEG in portable electronics much more practical and leading to a significant output improvement. The STEG with micro-patterned polydimethylsiloxane surface achieved an output voltage of over 200 V with a current density of 4.7 μA/cm{sup 2}. With human body conduit, the output current increased by 39% and the amount of charge that transferred increased by 34% compared to the results with grounded electrode. A larger increment of 210% and 81% was obtained in the case of STEG with a large-size flat polyethylene terephthalate surface.

  20. A Novel Human Body Area Network for Brain Diseases Analysis.

    PubMed

    Lin, Kai; Xu, Tianlang

    2016-10-01

    Development of wireless sensor and mobile communication technology provide an unprecedented opportunity for realizing smart and interactive healthcare systems. Designing such systems aims to remotely monitor the health and diagnose the diseases for users. In this paper, we design a novel human body area network for brain diseases analysis, which is named BABDA. Considering the brain is one of the most complex organs in the human body, the BABDA system provides four function modules to ensure the high quality of the analysis result, which includes initial data collection, data correction, data transmission and comprehensive data analysis. The performance evaluation conducted in a realistic environment with several criteria shows the availability and practicability of the BABDA system. PMID:27526187

  1. Major Findings from The Changing Body: Health, Nutrition, and Human Development in the Western World since 1700

    PubMed Central

    Fogel, Robert W.; Grotte, Nathaniel

    2013-01-01

    This paper discusses findings from The Changing Body: Health, Nutrition, and Human Development in the Western World since 1700 (Cambridge University Press) The book is built on the authors’ work with 300 years of height and nutrition data and discusses their findings in the context of technophysio evolution, a uniquely modern form of rapid physiological development, the result of humanity’s ability to control its environment and create technological innovations to adapt to it. PMID:26413098

  2. Telomerase RNA Accumulates in Cajal Bodies in Human Cancer Cells

    PubMed Central

    Zhu, Yusheng; Tomlinson, Rebecca L.; Lukowiak, Andrew A.; Terns, Rebecca M.; Terns, Michael P.

    2004-01-01

    Telomerase synthesizes telomeric DNA repeats at the ends of eukaryotic chromosomes. The RNA component of the enzyme (hTR) provides the template for telomere synthesis, which is catalyzed by telomerase reverse transcriptase (hTERT). Little is known regarding the subcellular localization of hTR and hTERT and the pathway by which telomerase is assembled. Here we report the first glimpse of the detailed subcellular localization of endogenous hTR in human cells, which we obtained by fluorescence in situ hybridization (FISH). Our studies have revealed a distinctive hTR localization pattern in cancer cells. We have found that hTR accumulates within intranuclear foci called Cajal bodies in all typical tumor-derived cell lines examined (in which telomerase is active), but not in primary or ALT cells (where little or no hTERT is present). Accumulation of hTR in the Cajal bodies of primary cells is induced when hTERT is ectopically expressed. Moreover, we report that hTERT is also found in Cajal bodies. Our data suggest that Cajal bodies are involved in the assembly and/or function of human telomerase. PMID:14528011

  3. Modelling of electromagnetic wave interactions with the human body

    NASA Astrophysics Data System (ADS)

    Wong, Man-Faï; Wiart, Joe

    2005-07-01

    Electromagnetic modelling plays a more and more important role in the study of complex systems involving Maxwell phenomena, such as the interactions of radiowaves with the human body. Simulation then becomes a credible means in decision making, related to the engineering of complex electromagnetic systems. To increase confidence in the models with respect to reality, validation and uncertainty estimation methods are needed. The different dimensions of model validation are illustrated through dosimetry, i.e., quantification of human exposure to electromagnetic waves. To cite this article: M.-F. Wong, J. Wiart, C. R. Physique 6 (2005).

  4. Physiological mechanisms by which non-nutritive sweeteners may impact body weight and metabolism.

    PubMed

    Burke, Mary V; Small, Dana M

    2015-12-01

    Evidence linking sugar-sweetened beverage (SSB) consumption to weight gain and other negative health outcomes has prompted many individuals to resort to artificial, non-nutritive sweetener (NNS) substitutes as a means of reducing SSB intake. However, there is a great deal of controversy regarding the biological consequences of NNS use, with accumulating evidence suggesting that NNS consumption may influence feeding and metabolism via a variety of peripheral and central mechanisms. Here we argue that NNSs are not physiologically inert compounds and consider the potential biological mechanisms by which NNS consumption may impact energy balance and metabolic function, including actions on oral and extra-oral sweet taste receptors, and effects on metabolic hormone secretion, cognitive processes (e.g. reward learning, memory, and taste perception), and gut microbiota. PMID:26048305

  5. Effects of winter undernutrition on body composition and physiological profiles of white-tailed deer

    USGS Publications Warehouse

    DelGiudice, G.D.; Mech, L.D.; Seal, U.S.

    1990-01-01

    We examined the effects of undernutrition and recovery on body composition and blood and urinary profiles of 6 captive white-tailed deer (Odocoileus virginianus) between 18 December 1984 and 3 May 1985. Deer were weighed, and blood and urine were collected every 2 weeks from 10 January to 3 May. At Weeks 2, 8, and 14, body composition was estimated by the dilution of tritiated water technique and standard predictive equations. Feed intake decreased and cumulative mass loss increased during nutritional restriction. Baseline body composition included 62.1 .+-. 0.9 (SE)% water, 11.9 .+-. 1.0% fat, 20.5 .+-. 0.7% protein, and 4.5 .+-. 0.0% ash. Percent protein loss was linearly related (r2 = 0.91, P < 0.001) to percent mass loss. Peak mass loss from the beginning of the study (12.8 .+-. 2.0%) occurred at Week 12; estimated protein loss was 12.5%. Fat reserves were 85% depleted from Week 2 to Week 14. Elevated packed cell volume (PCV), serum calcium (Ca), cholesterol, triglycerides, and cortisol; and diminished serum urea nitrogen, thyroxine (T4), urinary urea nitrogen:creatinine and potassium:creatinine were associated with reduced food intake, mass loss, and decreases in body water, fat, and protein. Altered values of most of these blood and urinary characteristics reflected initiation of nutritional recovery after nutrition improved. Sequential data collection and the use of a combination of indices in blood or urine will yield the most useful assessments of animal nutrition and condition.

  6. Nonlinear systems dynamics in cardiovascular physiology: The heart rate delay map and lower body negative pressure

    NASA Technical Reports Server (NTRS)

    Hooker, John C.

    1990-01-01

    A preliminary study of the applicability of nonlinear dynamic systems analysis techniques to low body negative pressure (LBNP) studies. In particular, the applicability of the heart rate delay map is investigated. It is suggested that the heart rate delay map has potential as a supplemental tool in the assessment of subject performance in LBNP tests and possibly in the determination of susceptibility to cardiovascular deconditioning with spaceflight.

  7. Changing undergraduate human anatomy and physiology laboratories: perspectives from a large-enrollment course.

    PubMed

    Griff, Edwin R

    2016-09-01

    In the present article, a veteran lecturer of human anatomy and physiology taught several sections of the laboratory component for the first time and shares his observations and analysis from this unique perspective. The article discusses a large-enrollment, content-heavy anatomy and physiology course in relationship to published studies on learning and student self-efficacy. Changes in the laboratory component that could increase student learning are proposed. The author also points out the need for research to assess whether selective curricular changes could increase the depth of understanding and retention of learned material. PMID:27503898

  8. High School Students' Understanding of the Human Body System

    NASA Astrophysics Data System (ADS)

    Assaraf, Orit Ben-Zvi; Dodick, Jeff; Tripto, Jaklin

    2013-02-01

    In this study, 120 tenth-grade students from 8 schools were examined to determine the extent of their ability to perceive the human body as a system after completing the first stage in their biology curriculum - "The human body, emphasizing homeostasis". The students' systems thinking was analyzed according to the STH thinking model, which roughly divides it into three main levels that are arranged "pyramid" style, in an ascending order of difficulty: 1. Analysis of system components—the ability to identify the components and processes existing in the human body system; 2. Synthesis of system components—ability to identify dynamic relations within the system; 3. Implementation—ability to generalize and identify patterns in the system, and to identify its hidden dimensions. The students in this study proved largely incapable of achieving systems thinking beyond the primary STH level of identifying components. An overwhelming majority if their responses corresponded to this level of the STH model, further indicating a pronounced favoring of structure over process, and of larger, macro elements over microscopic ones.

  9. The effect of stress on core and peripheral body temperature in humans.

    PubMed

    Vinkers, Christiaan H; Penning, Renske; Hellhammer, Juliane; Verster, Joris C; Klaessens, John H G M; Olivier, Berend; Kalkman, Cor J

    2013-09-01

    Even though there are indications that stress influences body temperature in humans, no study has systematically investigated the effects of stress on core and peripheral body temperature. The present study therefore aimed to investigate the effects of acute psychosocial stress on body temperature using different readout measurements. In two independent studies, male and female participants were exposed to a standardized laboratory stress task (the Trier Social Stress Test, TSST) or a non-stressful control task. Core temperature (intestinal and temporal artery) and peripheral temperature (facial and body skin temperature) were measured. Compared to the control condition, stress exposure decreased intestinal temperature but did not affect temporal artery temperature. Stress exposure resulted in changes in skin temperature that followed a gradient-like pattern, with decreases at distal skin locations such as the fingertip and finger base and unchanged skin temperature at proximal regions such as the infra-clavicular area. Stress-induced effects on facial temperature displayed a sex-specific pattern, with decreased nasal skin temperature in females and increased cheek temperature in males. In conclusion, the amplitude and direction of stress-induced temperature changes depend on the site of temperature measurement in humans. This precludes a direct translation of the preclinical stress-induced hyperthermia paradigm, in which core temperature uniformly rises in response to stress to the human situation. Nevertheless, the effects of stress result in consistent temperature changes. Therefore, the present study supports the inclusion of body temperature as a physiological readout parameter of stress in future studies. PMID:23790072

  10. Mechanisms of temperature-dependent swimming: the importance of physics, physiology and body size in determining protist swimming speed.

    PubMed

    Beveridge, Oliver S; Petchey, Owen L; Humphries, Stuart

    2010-12-15

    Body temperatures and thus physiological rates of poikilothermic organisms are determined by environmental temperature. The power an organism has available for swimming is largely dependent on physiological rates and thus body temperature. However, retarding forces such as drag are contingent on the temperature-dependent physical properties of water and on an organism's size. Consequently, the swimming ability of poikilotherms is highly temperature dependent. The importance of the temperature-dependent physical properties of water (e.g. viscosity) in determining swimming speed is poorly understood. Here we propose a semi-mechanistic model to describe how biological rates, size and the physics of the environment contribute to the temperature dependency of microbial swimming speed. Data on the swimming speed and size of a predatory protist and its protist prey were collected and used to test our model. Data were collected by manipulating both the temperature and the viscosity (independently of temperature) of the organism's environment. Protists were either cultured in their test environment (for several generations) or rapidly exposed to their test environment to assess their ability to adapt or acclimate to treatments. Both biological rates and the physics of the environment were predicted to and observed to contribute to the swimming speed of protists. Body size was not temperature dependent, and protists expressed some ability to acclimate to changes in either temperature or viscosity. Overall, using our parameter estimates and novel model, we are able to suggest that 30 to 40% (depending on species) of the response in swimming speed associated with a reduction in temperature from 20 to 5°C is due to viscosity. Because encounter rates between protist predators and their prey are determined by swimming speed, temperature- and viscosity-dependent swimming speeds are likely to result in temperature- and viscosity-dependent trophic interactions. PMID:21113003

  11. An overview of artificial gravity. [effects on human performance and physiology

    NASA Technical Reports Server (NTRS)

    Stone, R. W., Jr.

    1973-01-01

    The unique characteristics of artificial gravity that affect human performance and physiology in an artificial gravity environment are reviewed. The rate at which these unique characteristics change decreases very rapidly with increasing radius of a rotating vehicle used to produce artificial gravity. Reducing their influence on human performance or physiology by increasing radius becomes a situation of very rapidly diminishing returns. A review of several elements of human performance has developed criteria relative to the sundry characteristics of artificial gravity. A compilation of these criteria indicates that the maximum acceptable rate of rotation, leg heaviness while walking, and material handling are the factors that define the minimum acceptable radius. The ratio of Coriolis force to artificial weight may also be significant. Based on current knowledge and assumptions for the various criteria, a minimum radius between 15.2 and 16.8 m seems desirable.

  12. Stability of carbon nanotube yarn biofuel cell in human body fluid

    NASA Astrophysics Data System (ADS)

    Kwon, Cheong Hoon; Lee, Jae Ah; Choi, Young-Bong; Kim, Hyug-Han; Spinks, Geoffrey M.; Lima, Márcio D.; Baughman, Ray H.; Kim, Seon Jeong

    2015-07-01

    High performance with stability, easy-handling electrodes, and biofluid-flow controllable system with mechanical strength of the biofuel cell can be considered as the critical issues for future human body implant. These three challenges are sufficiently considered by using the effective platform regarding the high surface area from multi-walled carbon nanotube-conducting polymer with poly(3,4-ethylenedioxythiophene), and size/shape dependent flexible yarn electrodes for the implantation of biofuel cell. High power biofuel cell of mW cm-2 range in physiological condition (low glucose-containing phosphate buffered saline solution and human blood serum) controlling the stirring degree is also first demonstrated for future implantation in this study. Biofuel cells for future implantation in human body vitally require long-term stability and high power outputs. We have demonstrated that a high-surface area yarn-based biofuel cell retained over 70% of its initial power output after an extended 20 days period of continuous operation in human blood serum, while delivering a power density of ∼1.0 mW cm-2. Subsequently, our enhanced enzymatic biofuel cell system would be potentially used as an innovative power source for the next generation implantable electronics.

  13. Accelerated generation of human induced pluripotent stem cells with retroviral transduction and chemical inhibitors under physiological hypoxia.

    PubMed

    Shimada, Hidenori; Hashimoto, Yoshiya; Nakada, Akira; Shigeno, Keiji; Nakamura, Tatsuo

    2012-01-13

    Induced pluripotent stem (iPS) cells are generated from somatic cells by the forced expression of a defined set of pluripotency-associated transcription factors. Human iPS cells can be propagated indefinitely, while maintaining the capacity to differentiate into all cell types in the body except for extra-embryonic tissues. This technology not only represents a new way to use individual-specific stem cells for regenerative medicine but also constitutes a novel method to obtain large amounts of disease-specific cells for biomedical research. Despite their great potential, the long reprogramming process (up to 1month) remains one of the most significant challenges facing standard virus-mediated methodology. In this study, we report the accelerated generation of human iPS cells from adipose-derived stem (ADS) cells, using a new combination of chemical inhibitors under a setting of physiological hypoxia in conjunction with retroviral transduction of Oct4, Sox2, Klf4, and L-Myc. Under optimized conditions, we observed human embryonic stem (ES)-like cells as early as 6 days after the initial retroviral transduction. This was followed by the emergence of fully reprogrammed cells bearing Tra-1-81-positive and DsRed transgene-silencing properties on day 10. The resulting cell lines resembled human ES cells in many respects including proliferation rate, morphology, pluripotency-associated markers, global gene expression patterns, genome-wide DNA methylation states, and the ability to differentiate into all three of the germ layers, both in vitro and in vivo. Our method, when combined with chemical inhibitors under conditions of physiological hypoxia, offers a powerful tool for rapidly generating bona fide human iPS cells and facilitates the application of iPS cell technology to biomedical research. PMID:22172948

  14. Purification, characterization and physiological significance of a chitinase from the pilei of Coprinopsis cinerea fruiting bodies.

    PubMed

    Zhou, Yajun; Kang, Liqin; Niu, Xin; Wang, Jun; Liu, Zhonghua; Yuan, Sheng

    2016-06-01

    We purified a chitinase from pilei extractions of Coprinopsis cinerea fruiting bodies by ammonium sulfate precipitation and CM Sepharose cation exchange chromatography. MALDI-TOF/TOF MS analysis characterized this purified chitinase as a putative class V chitinase, ChiB1. ChiB1 hydrolyzed colloidal chitin and chitosan, whereas it did not hydrolyze chitin powder. ChiB1 cleaved only pNP-(GlcNAc)2, rather than pNP-GlcNAc or pNP-(Glc-NAc)3, to release nitrophenol. ChiB1 preferably and progressively released (GlcNAc)2 from (GlcNAc)6 and digested (GlcNAc)6 to two molecules of (GlcNAc)3 in a small proportion, but did not split (GlcNAc)2, so it is an exochitinase. ChiB1 has an optimum temperature range of 35°C to 40°C and an optimum pH of 5.0. ChiB1 exhibited Km and Vmax values of 2.63 mg ml(-1) and 2.31 μmol min(-1) mg protein(-1) for colloidal chitin, respectively. The ChiB1 gene, along with another putative endochitinase (class III chitinase gene), was expressed dominantly among eight predicted chitinase genes in the genome, and its expression level increased with the maturation of fruiting bodies. ChiB1 incubation released a large amount of soluble β-glucan fractions from alkali-insoluble cell wall fractions of C. cinerea fruiting bodies, thereby it may promote the degradation of cell walls in synergy with the β-1,3-glucanases during pileus autolysis. PMID:27190145

  15. Using pairs of physiological models to estimate temporal variation in amphibian body temperature.

    PubMed

    Roznik, Elizabeth A; Alford, Ross A

    2014-10-01

    Physical models are often used to estimate ectotherm body temperatures, but designing accurate models for amphibians is difficult because they can vary in cutaneous resistance to evaporative water loss. To account for this variability, a recently published technique requires a pair of agar models that mimic amphibians with 0% and 100% resistance to evaporative water loss; the temperatures of these models define the lower and upper boundaries of possible amphibian body temperatures for the location in which they are placed. The goal of our study was to develop a method for using these pairs of models to estimate parameters describing the distributions of body temperatures of frogs under field conditions. We radiotracked green-eyed treefrogs (Litoria serrata) and collected semi-continuous thermal data using both temperature-sensitive radiotransmitters with an automated datalogging receiver, and pairs of agar models placed in frog locations, and we collected discrete thermal data using a non-contact infrared thermometer when frogs were located. We first examined the accuracy of temperature-sensitive transmitters in estimating frog body temperatures by comparing transmitter data with direct temperature measurements taken simultaneously for the same individuals. We then compared parameters (mean, minimum, maximum, standard deviation) characterizing the distributions of temperatures of individual frogs estimated from data collected using each of the three methods. We found strong relationships between thermal parameters estimated from data collected using automated radiotelemetry and both types of thermal models. These relationships were stronger for data collected using automated radiotelemetry and impermeable thermal models, suggesting that in the field, L. serrata has a relatively high resistance to evaporative water loss. Our results demonstrate that placing pairs of thermal models in frog locations can provide accurate estimates of the distributions of temperatures

  16. Passive acoustic monitoring of human physiology during activity indicates health and performance of soldiers and firefighters

    NASA Astrophysics Data System (ADS)

    Scanlon, Michael V.

    2003-04-01

    The Army Research Laboratory has developed a unique gel-coupled acoustic physiological monitoring sensor that has acoustic impedance properties similar to the skin. This facilitates the transmission of body sounds into the sensor pad, yet significantly repels ambient airborne noises due to an impedance mismatch. The sensor's sensitivity and bandwidth produce excellent signatures for detection and spectral analysis of diverse physiological events. Acoustic signal processing detects heartbeats, breaths, wheezes, coughs, blood pressure, activity, motion, and voice for communication and automatic speech recognition. The health and performance of soldiers, firefighters, and other first responders in strenuous and hazardous environments can be continuously and remotely monitored with body-worn acoustic sensors. Comfortable acoustic sensors can be in a helmet or in a strap around the neck, chest, and wrist. Noise-canceling sensor arrays help remove out-of-phase motion noise and enhance covariant physiology by using two acoustic sensors on the front sides of the neck and two additional acoustic sensors on each wrist. Pulse wave transit time between neck and wrist acoustic sensors will indicate systolic blood pressure. Larger torso-sized arrays can be used to acoustically inspect the lungs and heart, or built into beds for sleep monitoring. Acoustics is an excellent input for sensor fusion.

  17. Modeling of Spinal Column of Seated Human Body under Exposure to Whole-Body Vibration

    NASA Astrophysics Data System (ADS)

    Tamaoki, Gen; Yoshimura, Takuya; Kuriyama, Kaoru; Nakai, Kazuma

    In vehicle systems occupational drivers might expose themselves to vibration for a long time. This may cause illness of the spinal column such as low back pain. Therefore, it is necessary to evaluate the influence of vibration to the spinal column. Thus the modeling of seated human body is conducted in order to evaluate the effect of whole-body vibration to the spinal column. This model has the spinal column and the support structures such as the muscles of the back and the abdomen. The spinal column is made by the vertebrae and the intervertebral disks that are considered the rigid body and the rotational spring and damper respectively. The parameter of this model is decided by the literature and the body type of the subject with respect to the mass and the model structure. And stiffness and damping parameters are searched by fitting the model simulation results to the experimental measured data with respect to the vibration transmissibilities from the seat surface to the spinal column and the head and with respect to the driving-point apparent mass. In addition, the natural modes of the model compare with the result of experimental modal analysis. The influence of the abdomen and the muscles of the back are investigated by comparing three models with respect to above vibration characteristics. Three model are the proposed model, the model that has the spinal column and the model that has the muscles of the back in addition to the spinal column.

  18. Physiological Effects Associated with Quinoa Consumption and Implications for Research Involving Humans: a Review.

    PubMed

    Simnadis, Thomas George; Tapsell, Linda C; Beck, Eleanor J

    2015-09-01

    Quinoa is a pseudo-grain consumed as a dietary staple in South America. In recent years, consumer demand for quinoa in the developed world has grown steadily. Its perceived health benefits have been cited as a driving force behind this trend, but there are very few human studies investigating the impact of quinoa consumption. The aim of this review was to identify physiological effects of quinoa consumption with potential for human health. A critical evaluation of animal model studies was conducted. The quality of identified studies was assessed using a methodological quality assessment tool and summative conclusions were drawn to guide the direction of future human research. The majority of studies were of fair quality. Purported physiological effects of quinoa consumption included decreased weight gain, improved lipid profile and improved capacity to respond to oxidative stress. These physiological effects were attributed to the presence of saponins, protein and 20-hydroxyecdysone in the quinoa seed. The implications of these findings are that human studies should investigate the impact of quinoa consumption on weight gain and lipid levels. The role of quinoa as an antioxidant is still unclear and requires further elucidation in animal models. PMID:26249220

  19. Modeling of interactions of electromagnetic fields with human bodies

    NASA Astrophysics Data System (ADS)

    Caputa, Krzysztof

    Interactions of electromagnetic fields with the human body have been a subject of scientific interest and public concern. In recent years, issues in power line field effects and those of wireless telephones have been in the forefront of research. Engineering research compliments biological investigations by quantifying the induced fields in biological bodies due to exposure to external fields. The research presented in this thesis aims at providing reliable tools, and addressing some of the unresolved issues related to interactions with the human body of power line fields and fields produced by handheld wireless telephones. The research comprises two areas, namely development of versatile models of the human body and their visualisation, and verification and application of numerical codes to solve selected problems of interest. The models of the human body, which are based on the magnetic resonance scans of the body, are unique and differ considerably from other models currently available. With the aid of computer software developed, the models can be arranged to different postures, and medical devices can be accurately placed inside them. A previously developed code for modeling interactions of power line fields with biological bodies has been verified by rigorous, quantitative inter-laboratory comparison for two human body models. This code has been employed to model electromagnetic interference (EMI) of the magnetic field with implanted cardiac pacemakers. In this case, the correct placement and representation of the pacemaker leads are critical, as simplified computations have been shown to result in significant errors. In modeling interactions of wireless communication devices, the finite difference time domain technique (FDTD) has become a de facto standard. The previously developed code has been verified by comparison with the analytical solution for a conductive sphere. While previously researchers limited their verifications to principal axes of the sphere

  20. Using stimulation of the diving reflex in humans to teach integrative physiology.

    PubMed

    Choate, Julia K; Denton, Kate M; Evans, Roger G; Hodgson, Yvonne

    2014-12-01

    During underwater submersion, the body responds by conserving O2 and prioritizing blood flow to the brain and heart. These physiological adjustments, which involve the nervous, cardiovascular, and respiratory systems, are known as the diving response and provide an ideal example of integrative physiology. The diving reflex can be stimulated in the practical laboratory setting using breath holding and facial immersion in water. Our undergraduate physiology students complete a laboratory class in which they investigate the effects of stimulating the diving reflex on cardiovascular variables, which are recorded and calculated with a Finapres finger cuff. These variables include heart rate, cardiac output, stroke volume, total peripheral resistance, and arterial pressures (mean, diastolic, and systolic). Components of the diving reflex are stimulated by 1) facial immersion in cold water (15°C), 2) breathing with a snorkel in cold water (15°C), 3) facial immersion in warm water (30°C), and 4) breath holding in air. Statistical analysis of the data generated for each of these four maneuvers allows the students to consider the factors that contribute to the diving response, such as the temperature of the water and the location of the sensory receptors that initiate the response. In addition to providing specific details about the equipment, protocols, and learning outcomes, this report describes how we assess this practical exercise and summarizes some common student misunderstandings of the essential physiological concepts underlying the diving response. PMID:25434020

  1. Smart Sensors and Virtual Physiology Human Approach as a Basis of Personalized Therapies in Diabetes Mellitus

    PubMed Central

    Fernández Peruchena, Carlos M; Prado-Velasco, Manuel

    2010-01-01

    Diabetes mellitus (DM) has a growing incidence and prevalence in modern societies, pushed by the aging and change of life styles. Despite the huge resources dedicated to improve their quality of life, mortality and morbidity rates, these are still very poor. In this work, DM pathology is revised from clinical and metabolic points of view, as well as mathematical models related to DM, with the aim of justifying an evolution of DM therapies towards the correction of the physiological metabolic loops involved. We analyze the reliability of mathematical models, under the perspective of virtual physiological human (VPH) initiatives, for generating and integrating customized knowledge about patients, which is needed for that evolution. Wearable smart sensors play a key role in this frame, as they provide patient’s information to the models. A telehealthcare computational architecture based on distributed smart sensors (first processing layer) and personalized physiological mathematical models integrated in Human Physiological Images (HPI) computational components (second processing layer), is presented. This technology was designed for a renal disease telehealthcare in earlier works and promotes crossroads between smart sensors and the VPH initiative. We suggest that it is able to support a truly personalized, preventive, and predictive healthcare model for the delivery of evolved DM therapies. PMID:21625646

  2. Labile iron in cells and body fluids: physiology, pathology, and pharmacology

    PubMed Central

    Cabantchik, Zvi Ioav

    2014-01-01

    In living systems iron appears predominantly associated with proteins, but can also be detected in forms referred as labile iron, which denotes the combined redox properties of iron and its amenability to exchange between ligands, including chelators. The labile cell iron (LCI) composition varies with metal concentration and substances with chelating groups but also with pH and the medium redox potential. Although physiologically in the lower μM range, LCI plays a key role in cell iron economy as cross-roads of metabolic pathways. LCI levels are continually regulated by an iron-responsive machinery that balances iron uptake versus deposition into ferritin. However, LCI rises aberrantly in some cell types due to faulty cell utilization pathways or infiltration by pathological iron forms that are found in hemosiderotic plasma. As LCI attains pathological levels, it can catalyze reactive O species (ROS) formation that, at particular threshold, can surpass cellular anti-oxidant capacities and seriously damage its constituents. While in normal plasma and interstitial fluids, virtually all iron is securely carried by circulating transferrin (Tf; that renders iron essentially non-labile), in systemic iron overload (IO), the total plasma iron binding capacity is often surpassed by a massive iron influx from hyperabsorptive gut or from erythrocyte overburdened spleen and/or liver. As plasma Tf approaches iron saturation, labile plasma iron (LPI) emerges in forms that can infiltrate cells by unregulated routes and raise LCI to toxic levels. Despite the limited knowledge available on LPI speciation in different types and degrees of IO, LPI measurements can be and are in fact used for identifying systemic IO and for initiating/adjusting chelation regimens to attain full-day LPI protection. A recent application of labile iron assay is the detection of labile components in intravenous iron formulations per se as well as in plasma (LPI) following parenteral iron administration

  3. Influence of the circadian rhythm of body temperature on the physiological response to microwaves: Day versus night exposure

    SciTech Connect

    Lotz, W.G.

    1981-10-01

    The results of this study demonstrate an influence of the circadian rhythm on the effects of microwave exposure on plasma cortisol and rectal temperature. The lower rectal temperature during night exposures was presumably due to the lower sham-condition temperature at night, since the temperature increase over sham levels was similar for either day or night exposures. The absence of a cortisol response during night exposures may be simply related to the absolute body temperature reached, although more complex circadian influences cannot be eliminated by these data. Although the results were insufficient to provide a clear understanding of the mechanisms involved, it was shown conclusively that the responses studied depended not only on the independent variables of microwave exposure selected, but also on the baseline levels of the normal physiological state that existed at the time of exposure.

  4. Programming and Isolation of Highly Pure Physiologically and Pharmacologically Functional Sinus-Nodal Bodies from Pluripotent Stem Cells

    PubMed Central

    Jung, Julia Jeannine; Husse, Britta; Rimmbach, Christian; Krebs, Stefan; Stieber, Juliane; Steinhoff, Gustav; Dendorfer, Andreas; Franz, Wolfgang-Michael; David, Robert

    2014-01-01

    Summary Therapeutic approaches for “sick sinus syndrome” rely on electrical pacemakers, which lack hormone responsiveness and bear hazards such as infection and battery failure. These issues may be overcome via “biological pacemakers” derived from pluripotent stem cells (PSCs). Here, we show that forward programming of PSCs with the nodal cell inducer TBX3 plus an additional Myh6-promoter-based antibiotic selection leads to cardiomyocyte aggregates consisting of >80% physiologically and pharmacologically functional pacemaker cells. These induced sinoatrial bodies (iSABs) exhibited highly increased beating rates (300–400 bpm), coming close to those found in mouse hearts, and were able to robustly pace myocardium ex vivo. Our study introduces iSABs as highly pure, functional nodal tissue that is derived from PSCs and may be important for future cell therapies and drug testing in vitro. PMID:24936448

  5. Vascularization of Air Sinuses and Fat Bodies in the Head of the Bottlenose Dolphin (Tursiops truncatus): Morphological Implications on Physiology

    PubMed Central

    Costidis, Alex; Rommel, Sentiel A.

    2012-01-01

    Cetaceans have long been considered capable of limiting diving-induced nitrogen absorption and subsequent decompression sickness through a series of behavioral, anatomical, and physiological adaptations. Recent studies however suggest that in some situations these adaptive mechanisms might be overcome, resulting in lethal and sublethal injuries. Perhaps most relevant to this discussion is the finding of intravascular gas and fat emboli in mass-stranded beaked whales. Although the source of the gas emboli has as yet to been ascertained, preliminary findings suggest nitrogen is the primary component. Since nitrogen gas embolus formation in divers is linked to nitrogen saturation, it seems premature to dismiss similar pathogenic mechanisms in breath-hold diving cetaceans. Due to the various anatomical adaptations in cetacean lungs, the pulmonary system is thought of as an unlikely site of significant nitrogen absorption. The accessory sinus system on the ventral head of odontocete cetaceans contains a sizeable volume of air that is exposed to the changing hydrostatic pressures during a dive, and is intimately associated with vasculature potentially capable of absorbing nitrogen through its walls. The source of the fat emboli has also remained elusive. Most mammalian fat deposits are considered poorly vascularized and therefore unlikely sites of intravascular introduction of lipid, although cetacean blubber may not be as poorly vascularized as previously thought. We present new data on the vasculature of air sinuses and acoustic fat bodies in the head of bottlenose dolphins and compare it to published accounts. We show that the mandibular fat bodies and accessory sinus system are associated with extensive venous plexuses and suggest potential physiological and pathological implications. PMID:22969724

  6. Widespread seasonal gene expression reveals annual differences in human immunity and physiology.

    PubMed

    Dopico, Xaquin Castro; Evangelou, Marina; Ferreira, Ricardo C; Guo, Hui; Pekalski, Marcin L; Smyth, Deborah J; Cooper, Nicholas; Burren, Oliver S; Fulford, Anthony J; Hennig, Branwen J; Prentice, Andrew M; Ziegler, Anette-G; Bonifacio, Ezio; Wallace, Chris; Todd, John A

    2015-01-01

    Seasonal variations are rarely considered a contributing component to human tissue function or health, although many diseases and physiological process display annual periodicities. Here we find more than 4,000 protein-coding mRNAs in white blood cells and adipose tissue to have seasonal expression profiles, with inverted patterns observed between Europe and Oceania. We also find the cellular composition of blood to vary by season, and these changes, which differ between the United Kingdom and The Gambia, could explain the gene expression periodicity. With regards to tissue function, the immune system has a profound pro-inflammatory transcriptomic profile during European winter, with increased levels of soluble IL-6 receptor and C-reactive protein, risk biomarkers for cardiovascular, psychiatric and autoimmune diseases that have peak incidences in winter. Circannual rhythms thus require further exploration as contributors to various aspects of human physiology and disease. PMID:25965853

  7. Widespread seasonal gene expression reveals annual differences in human immunity and physiology

    PubMed Central

    Dopico, Xaquin Castro; Evangelou, Marina; Ferreira, Ricardo C.; Guo, Hui; Pekalski, Marcin L.; Smyth, Deborah J.; Cooper, Nicholas; Burren, Oliver S.; Fulford, Anthony J.; Hennig, Branwen J.; Prentice, Andrew M.; Ziegler, Anette-G.; Bonifacio, Ezio; Wallace, Chris; Todd, John A.

    2015-01-01

    Seasonal variations are rarely considered a contributing component to human tissue function or health, although many diseases and physiological process display annual periodicities. Here we find more than 4,000 protein-coding mRNAs in white blood cells and adipose tissue to have seasonal expression profiles, with inverted patterns observed between Europe and Oceania. We also find the cellular composition of blood to vary by season, and these changes, which differ between the United Kingdom and The Gambia, could explain the gene expression periodicity. With regards to tissue function, the immune system has a profound pro-inflammatory transcriptomic profile during European winter, with increased levels of soluble IL-6 receptor and C-reactive protein, risk biomarkers for cardiovascular, psychiatric and autoimmune diseases that have peak incidences in winter. Circannual rhythms thus require further exploration as contributors to various aspects of human physiology and disease. PMID:25965853

  8. Physiological response to whole-body vibration in athletes and sedentary subjects.

    PubMed

    Gojanovic, B; Feihl, F; Gremion, G; Waeber, B

    2014-01-01

    Whole-body vibration (WBV) is a new exercise method, with good acceptance among sedentary subjects. The metabolic response to WBV has not been well documented. Three groups of male subjects, inactive (SED), endurance (END) and strength trained (SPRINT) underwent a session of side-alternating WBV composed of three 3-min exercises (isometric half-squat, dynamic squat, dynamic squat with added load), and repeated at three frequencies (20, 26 and 32 Hz). VO(2), heart rate and Borg scale were monitored. Twenty-seven healthy young subjects (10 SED, 8 SPRINT and 9 END) were included. When expressed in % of their maximal value recorded in a treadmill test, both the peak oxygen consumption (VO(2)) and heart rate (HR) attained during WBV were greatest in the SED, compared to the other two groups (VO(2): 59.3 % in SED vs 50.8 % in SPRINT and 48.0 % in END, p<0.01; HR 82.7 % in SED vs 80.4 % in SPRINT and 72.4 % in END, p<0.05). In conclusions, the heart rate and metabolic response to WBV differs according to fitness level and type, exercise type and vibration frequency. In SED, WBV can elicit sufficient cardiovascular response to benefit overall fitness and thus be a potentially useful modality for the reduction of cardiovascular risk. PMID:25157652

  9. Leveraging knowledge from physiological data: on-body heat stress risk prediction with sensor networks.

    PubMed

    Gaura, Elena; Kemp, John; Brusey, James

    2013-12-01

    The paper demonstrates that wearable sensor systems, coupled with real-time on-body processing and actuation, can enhance safety for wearers of heavy protective equipment who are subjected to harsh thermal environments by reducing risk of Uncompensable Heat Stress (UHS). The work focuses on Explosive Ordnance Disposal operatives and shows that predictions of UHS risk can be performed in real-time with sufficient accuracy for real-world use. Furthermore, it is shown that the required sensory input for such algorithms can be obtained with wearable, non-intrusive sensors. Two algorithms, one based on Bayesian nets and another on decision trees, are presented for determining the heat stress risk, considering the mean skin temperature prediction as a proxy. The algorithms are trained on empirical data and have accuracies of 92.1±2.9% and 94.4±2.1%, respectively when tested using leave-one-subject-out cross-validation. In applications such as Explosive Ordnance Disposal operative monitoring, such prediction algorithms can enable autonomous actuation of cooling systems and haptic alerts to minimize casualties. PMID:24473550

  10. Development of a lower body negative pressure box with an environmental control system for physiological studies.

    PubMed

    Russomano, T; Falcao, F; Gurgel, J; Piccoli, L; Porto, F; Dalmarco, G; de Azevedo, D F G; Allan, J; Beck, L; Petrat, G; Thompsen, S

    2005-01-01

    A headward fluid shift occurs during microgravity exposure, which causes the cardiovascular adaptive syndrome. Different countermeasures have been proposed to decrease its symptomatology, like the application of lower body negative pressure (LBNP). A LBNP box with an environment control system was developed, aiming to improve features of LBNP boxes used worldwide. It consists of five carbon steel ribs in the shape of a cylinder, which is wrapped with high pressure resistant and transparent vinyl. Inner and outer-wheeled trolleys can comfortably and easily move the subject in and out of the box. A custom-made skirt is secured around the subject's waist by an adjustable belt. The other end is secured between two window-type wooden structures, which seal the LBNP box. Inlet and an outlet valves connect the external to the internal environment of the chamber and tube system allows air to circulate gently. Electronic sensors are used to adjust the airflow keeping a pre-set negative pressure without changing humidity and temperature inside the box. Structural, pressure profile and leaking tests were performed with successful results. The improvements of the present LBNP box have substantially decreased the undesirable side effects of uncontrolled environment conditions during rapid pressure changes, and increased test subjects' comfort. PMID:17281238

  11. A potential role for tissue kallikrein-related peptidases in human cervico-vaginal physiology.

    PubMed

    Shaw, Julie L V; Diamandis, Eleftherios P

    2008-06-01

    Human tissue kallikrein-related peptidases (KLK) are a family of 15 genes located on chromosome 19q13.4 that encode secreted serine proteases with trypsin- and/or chymotrypsin-like activity. Relatively large levels of many KLKs are present in human cervico-vaginal fluid (CVF) and in the supernatant of cultured human vaginal epithelial cells. Many KLKs are also hormonally regulated in vaginal epithelial cells, particularly by glucocorticoids and estrogens. The physiological role of KLK in the vagina is currently unknown; however, analysis of the CVF proteome has revealed clues for potential KLK functions in this environment. Here, we detail potential roles for KLKs in cervico-vaginal physiology. First, we suggest that KLKs play a role in the vagina similar to their role in skin physiology: (1) in the desquamation of vaginal epithelial cells, similar to their activity in the desquamation of skin corneocytes; and (2) in their ability to activate antimicrobial proteins in CVF as they do in sweat. Consequently, we hypothesize that dysregulated KLK expression in the vagina could lead to the development of pathological conditions such as desquamative inflammatory vaginitis. Second, we propose that KLKs may play a role in premature rupture of membranes and pre-term birth through their cleavage of fetal membrane extracellular matrix proteins. PMID:18627298

  12. Probiotics as flourishing benefactors for the human body.

    PubMed

    Broekaert, Ilse J; Walker, W Allan

    2006-01-01

    This article provides a comprehensive review of the beneficial effects of various strains of probiotics in preventing and treating certain diseases. Currently, changed lifestyles as well as the increased use of antibiotics are significant factors challenging the preservation of a healthy intestinal microflora. The concept of probiotics is to restore and uphold a microflora advantageous for the human body. Probiotics are found in a number of fermented dairy products, infant formula, and dietary supplements. In the presence of prebiotics, which are nondigestible food ingredients favorable for probiotic growth, their survival in the intestine is ameliorated. PMID:16552297

  13. Diamond stabilization of ice multilayers at human body temperature

    NASA Astrophysics Data System (ADS)

    Wissner-Gross, Alexander D.; Kaxiras, Efthimios

    2007-08-01

    Diamond is a promising material for wear-resistant medical coatings. Here we report a remarkable increase in the melting point of ice resting on a diamond (111) surface modified with a submonolayer of Na+ . Our molecular dynamics simulations show that the interfacial ice bilayer melts at a temperature 130K higher than in free ice, and relatively thick ice films ( 2.6nm at 298K and 2.2nm at 310K ) are stabilized by dipole interactions with the substrate. This unique physical effect may enable biocompatibility-enhancing ice overcoatings for diamond at human body temperature.

  14. The Physiological Effect of Human Grooming on the Heart Rate and the Heart Rate Variability of Laboratory Non-Human Primates: A Pilot Study in Male Rhesus Monkeys

    PubMed Central

    Grandi, Laura Clara; Ishida, Hiroaki

    2015-01-01

    Grooming is a widespread, essential, and complex behavior with social and affiliative valence in the non-human primate world. Its impact at the autonomous nervous system level has been studied during allogrooming among monkeys living in a semi-naturalistic environment. For the first time, we investigated the effect of human grooming to monkey in a typical experimental situation inside laboratory. We analyzed the autonomic response of male monkeys groomed by a familiar human (experimenter), in terms of the heart rate (HR) and heart rate variability (HRV) at different body parts. We considered the HRV in both the time (SDNN, RMSSD, and RMSSD/SDNN) and the frequency domain (HF, LF, and LF/HF). For this purpose, we recorded the electrocardiogram of two male rhesus monkeys seated in a primate chair while the experimenter groomed their mouth, chest, or arm. We demonstrated that (1) the grooming carried out by a familiar human determined a decrement of the HR and an increment of the HRV; (2) there was a difference in relation to the groomed body part. In particular, during grooming the mouth the HRV was higher than during grooming the arm and the chest. Taken together, the results represent the first evidence that grooming carried out by a familiar human on experimental monkeys has the comparable positive physiological effect of allogrooming between conspecifics. Moreover, since the results underlined the positive modulation of both HR and HRV, the present study could be a starting point to improve the well-being of non-human primates in experimental condition by means of grooming by a familiar person. PMID:26664977

  15. Photonic emission from human body controlled by will

    NASA Astrophysics Data System (ADS)

    Matsueda, Hideaki

    2000-03-01

    Recent technology of photonic measurements provides direct observation of the weak modulation in the radiation from a human body, which may depends on psychological or mental conditions of the subject. We have been applying the photonic technology to detect the intensity modulation and spectra, from near ultraviolet to near infrared regime, to human subjects who claim healing ability in the art of qi and other Japanese holistic practices. The photomultiplier signal intensity has been observed to change in `on' and `off' and oscillatory manners, in accordance with the will of subjects. We will discuss the results of our optical as well as electrical measurements comprehensively, to investigate into this unexplored fields for the western science.

  16. A probabilistic model of human variability in physiology for future application to dose reconstruction and QIVIVE

    PubMed Central

    McNally, Kevin; Loizou, George D.

    2015-01-01

    The risk assessment of environmental chemicals and drugs is undergoing a paradigm shift in approach which seeks the full replacement of animal testing with high throughput, mechanistic, in vitro systems. This new approach will be reliant on the measurement in vitro, of concentration-dependent responses where prolonged excessive perturbations of specific biochemical pathways are likely to lead to adverse health effects in an intact organism. Such an approach requires a framework, into which disparate data generated by in vitro, in silico, and in chemico systems can be integrated and utilized for quantitative in vitro-to-in vivo extrapolation (QIVIVE), ultimately to the human population level. Physiologically based pharmacokinetic (PBPK) models are ideally suited to this and are needed to translate in vitro concentration- response relationships to an exposure or dose, route and duration regime in human populations. Thus, a realistic description of the variation in the physiology of the human population being modeled is critical. Whilst various studies in the past decade have made progress in describing human variability, the algorithms are typically coded in computer programs and as such are unsuitable for reverse dosimetry. In this report we overcome this limitation by developing a hierarchical statistical model using standard probability distributions for the specification of a virtual US and UK human population. The work draws on information from both population databases and cadaver studies. PMID:26528180

  17. Low physiological levels of prostaglandins E2 and F2α improve human sperm functions.

    PubMed

    Rios, Mariana; Carreño, Daniela V; Oses, Carolina; Barrera, Nelson; Kerr, Bredford; Villalón, Manuel

    2016-03-01

    Prostaglandins (PGs) have been reported to be present in the seminal fluid and cervical mucus, affecting different stages of sperm maturation from spermatogenesis to the acrosome reaction. This study assessed the effects of low physiological PGE2 and PGF2α concentrations on human sperm motility and on the ability of the spermatozoa to bind to the zona pellucida (ZP). Human spermatozoa were isolated from seminal samples with normal concentration and motility parameters and incubated with 1μM PGE2, 1μM PGF2α or control solution to determine sperm motility and the ability to bind to human ZP. The effects of both PGs on intracellular calcium levels were determined. Incubation for 2 or 18h with PGE2 or PGF2α resulted in a significant (P<0.05) increase in the percentage of spermatozoa with progressive motility. In contrast with PGF2α, PGE2 alone induced an increase in sperm intracellular calcium levels; however, the percentage of sperm bound to the human ZP was doubled for both PGs. These results indicate that incubation of human spermatozoa with low physiological levels of PGE2 or PGF2α increases sperm functions and could improve conditions for assisted reproduction protocols. PMID:25123052

  18. Estructura y Funcionamiento del Cuerpo Humano. Prontuario. Guia del Maestro. Documento de Trabajo (Structure and Function of the Human Body. Handbook and Teacher's Guide. Working Document).

    ERIC Educational Resources Information Center

    Puerto Rico State Dept. of Education, Hato Rey. Area for Vocational and Technical Education.

    This handbook and teacher's guide are for a 37-week course on the human body, intended for secondary or postsecondary students in allied health occupations. The syllabus lists general objectives and the number of hours and weeks devoted to each unit. A course outline is provided for five units: anatomy and physiology terminology; general…

  19. Dynamic Propagation Channel Characterization and Modeling for Human Body Communication

    PubMed Central

    Nie, Zedong; Ma, Jingjing; Li, Zhicheng; Chen, Hong; Wang, Lei

    2012-01-01

    This paper presents the first characterization and modeling of dynamic propagation channels for human body communication (HBC). In-situ experiments were performed using customized transceivers in an anechoic chamber. Three HBC propagation channels, i.e., from right leg to left leg, from right hand to left hand and from right hand to left leg, were investigated under thirty-three motion scenarios. Snapshots of data (2,800,000) were acquired from five volunteers. Various path gains caused by different locations and movements were quantified and the statistical distributions were estimated. In general, for a given reference threshold è = −10 dB, the maximum average level crossing rate of the HBC was approximately 1.99 Hz, the maximum average fade time was 59.4 ms, and the percentage of bad channel duration time was less than 4.16%. The HBC exhibited a fade depth of −4 dB at 90% complementary cumulative probability. The statistical parameters were observed to be centered for each propagation channel. Subsequently a Fritchman model was implemented to estimate the burst characteristics of the on-body fading. It was concluded that the HBC is motion-insensitive, which is sufficient for reliable communication link during motions, and therefore it has great potential for body sensor/area networks. PMID:23250278

  20. Cytogenetic Features of Human Head and Body Lice (Phthiraptera: Pediculidae).

    PubMed

    Bressa, María José; Papeschi, Alba Graciela; Toloza, Ariel Ceferino

    2015-09-01

    The genus Pediculus L. that parasitize humans comprise two subspecies: the head lice Pediculus humanus capitis De Geer and the body lice Pediculus humanus humanus De Geer. Despite the 200 yr of the first description of these two species, there is still a long debate about their taxonomic status. Some authors proposed that these organisms are separate species, conspecifics, or grouped in clades. The sequencing of both forms indicated that the difference between them is one gene absent in the head louse. However, their chromosomal number remains to be determined. In this study, we described the male and female karyotypes, and male meiosis of head and body lice, and examined the chromatin structure by means of C-banding. In P. h. humanus and P. h. capitis, the diploid chromosome complement was 2 n = 12 in both sexes. In oogonial prometaphase and metaphase and spermatogonial metaphase, it is evident that chromosomes lack of a primary constriction. No identifiable sex chromosomes or B chromosomes were observed in head and body lice. Neither chiasmata nor chromatin connections between homologous chromosomes were detected in male meiosis. The meiotic behaviour of the chromosomes showed that they are holokinetic. C-banding revealed the absence of constitutive heterochromatin. Our results provide relevant information to be used in mapping studies of genes associated with sex determination and environmental sensing and response. PMID:26336229

  1. Estimating psycho-physiological state of a human by speech analysis

    NASA Astrophysics Data System (ADS)

    Ronzhin, A. L.

    2005-05-01

    Adverse effects of intoxication, fatigue and boredom could degrade performance of highly trained operators of complex technical systems with potentially catastrophic consequences. Existing physiological fitness for duty tests are time consuming, costly, invasive, and highly unpopular. Known non-physiological tests constitute a secondary task and interfere with the busy workload of the tested operator. Various attempts to assess the current status of the operator by processing of "normal operational data" often lead to excessive amount of computations, poorly justified metrics, and ambiguity of results. At the same time, speech analysis presents a natural, non-invasive approach based upon well-established efficient data processing. In addition, it supports both behavioral and physiological biometric. This paper presents an approach facilitating robust speech analysis/understanding process in spite of natural speech variability and background noise. Automatic speech recognition is suggested as a technique for the detection of changes in the psycho-physiological state of a human that typically manifest themselves by changes of characteristics of voice tract and semantic-syntactic connectivity of conversation. Preliminary tests have confirmed that the statistically significant correlation between the error rate of automatic speech recognition and the extent of alcohol intoxication does exist. In addition, the obtained data allowed exploring some interesting correlations and establishing some quantitative models. It is proposed to utilize this approach as a part of fitness for duty test and compare its efficiency with analyses of iris, face geometry, thermography and other popular non-invasive biometric techniques.

  2. Overwinter survival of juvenile lake herring in relation to body size, physiological condition, energy stores, and food ration

    USGS Publications Warehouse

    Pangle, Kevin L.; Sutton, Trent M.; Kinnunen, Ronald E.; Hoff, Michael H.

    2004-01-01

    Populations of lake herring Coregonus artedi in Lake Superior have exhibited high recruitment variability over the past three decades. To improve our understanding of the mechanisms which influence year-class strength, we conducted a 225-d laboratory experiment to evaluate the effects of body size, physiological condition, energy stores, and food ration on the winter survival of age-0 lake herring. Small (total length (TL) range = 60–85 mm) and large (TL range = 86–110 mm) fish were maintained under thermal and photoperiod regimes that mimicked those in Lake Superior from October through May. Fish in each size-class were maintained at two feeding treatments: brine shrimp Artemiaspp. ad libitum and no food. The mortality of large lake herring (fed, 3.8%; starved, 20.1%) was significantly less than that of small fish (fed, 11.7%; starved, 32.0%). Body condition and crude lipid content declined for all fish over the experiment; however, these variables were significantly greater for large fed (0.68% and 9.8%) and small fed (0.65% and 7.3%) fish than large starved (0.49% and 5.7%) and small starved (0.45% and 4.8%) individuals. Final crude protein and gross energy contents were also significantly greater in large fed lake herring (17.6% and 1,966 cal/g), followed by small fed (17.1% and 1,497 cal/g), large starved (15.4% and 1,125 cal/g), and small starved (13.2% and 799 cal/g) fish. Lake herring that died during the experiment had significantly lower body condition and energy stores relative to those of the surviving fish. These results suggest that the depletion of energy stores contributes to greater winter mortality of small lake herring with limited energy uptake and may partially explain the variability in recruitment observed in Lake Superior.

  3. Influence of Urbanization on Body Size, Condition, and Physiology in an Urban Exploiter: A Multi-Component Approach.

    PubMed

    Meillère, Alizée; Brischoux, François; Parenteau, Charline; Angelier, Frédéric

    2015-01-01

    Consistent expanding urbanization dramatically transforms natural habitats and exposes organisms to novel environmental challenges, often leading to reduced species richness and diversity in cities. However, it remains unclear how individuals are affected by the urban environment and how they can or cannot adjust to the specific characteristics of urban life (e.g. food availability). In this study, we used an integrative multi-component approach to investigate the effects of urbanization on the nutritional status of house sparrows (Passer domesticus). We assessed several morphological and physiological indices of body condition in both juveniles (early post-fledging) and breeding adults from four sites with different levels of urbanization in France, Western Europe. We found that sparrows in more urbanized habitats have reduced body size and body mass compared to their rural conspecifics. However, we did not find any consistent differences in a number of complementary indices of condition (scaled mass index, muscle score, hematocrit, baseline and stress-induced corticosterone levels) between urban and rural birds, indicating that urban sparrows may not be suffering nutritional stress. Our results suggest that the urban environment is unlikely to energetically constrain adult sparrows, although other urban-related variables may constrain them. On the other hand, we found significant difference in juvenile fat scores, suggesting that food types provided to young sparrows differed highly between habitats. In addition to the observed smaller size of urban sparrows, these results suggest that the urban environment is inadequate to satisfy early-life sparrows' nutritional requirements, growth, and development. The urban environment may therefore have life-long consequences for developing birds. PMID:26270531

  4. Influence of Urbanization on Body Size, Condition, and Physiology in an Urban Exploiter: A Multi-Component Approach

    PubMed Central

    Meillère, Alizée; Brischoux, François; Parenteau, Charline; Angelier, Frédéric

    2015-01-01

    Consistent expanding urbanization dramatically transforms natural habitats and exposes organisms to novel environmental challenges, often leading to reduced species richness and diversity in cities. However, it remains unclear how individuals are affected by the urban environment and how they can or cannot adjust to the specific characteristics of urban life (e.g. food availability). In this study, we used an integrative multi-component approach to investigate the effects of urbanization on the nutritional status of house sparrows (Passer domesticus). We assessed several morphological and physiological indices of body condition in both juveniles (early post-fledging) and breeding adults from four sites with different levels of urbanization in France, Western Europe. We found that sparrows in more urbanized habitats have reduced body size and body mass compared to their rural conspecifics. However, we did not find any consistent differences in a number of complementary indices of condition (scaled mass index, muscle score, hematocrit, baseline and stress-induced corticosterone levels) between urban and rural birds, indicating that urban sparrows may not be suffering nutritional stress. Our results suggest that the urban environment is unlikely to energetically constrain adult sparrows, although other urban-related variables may constrain them. On the other hand, we found significant difference in juvenile fat scores, suggesting that food types provided to young sparrows differed highly between habitats. In addition to the observed smaller size of urban sparrows, these results suggest that the urban environment is inadequate to satisfy early-life sparrows’ nutritional requirements, growth, and development. The urban environment may therefore have life-long consequences for developing birds. PMID:26270531

  5. Dissection of human vitreous body elements for proteomic analysis.

    PubMed

    Skeie, Jessica M; Mahajan, Vinit B

    2011-01-01

    The vitreous is an optically clear, collagenous extracellular matrix that fills the inside of the eye and overlies the retina. (1,2) Abnormal interactions between vitreous substructures and the retina underlie several vitreoretinal diseases, including retinal tear and detachment, macular pucker, macular hole, age-related macular degeneration, vitreomacular traction, proliferative vitreoretinopathy, proliferative diabetic retinopathy, and inherited vitreoretinopathies. (1,2) The molecular composition of the vitreous substructures is not known. Since the vitreous body is transparent with limited surgical access, it has been difficult to study its substructures at the molecular level. We developed a method to separate and preserve these tissues for proteomic and biochemical analysis. The dissection technique in this experimental video shows how to isolate vitreous base, anterior hyaloid, vitreous core, and vitreous cortex from postmortem human eyes. One-dimensional SDS-PAGE analyses of each vitreous component showed that our dissection technique resulted in four unique protein profiles corresponding to each substructure of the human vitreous body. Identification of differentially compartmentalized proteins will reveal candidate molecules underlying various vitreoretinal diseases. PMID:21304469

  6. Measuring accurate body parameters of dressed humans with large-scale motion using a Kinect sensor.

    PubMed

    Xu, Huanghao; Yu, Yao; Zhou, Yu; Li, Yang; Du, Sidan

    2013-01-01

    Non-contact human body measurement plays an important role in surveillance, physical healthcare, on-line business and virtual fitting. Current methods for measuring the human body without physical contact usually cannot handle humans wearing clothes, which limits their applicability in public environments. In this paper, we propose an effective solution that can measure accurate parameters of the human body with large-scale motion from a Kinect sensor, assuming that the people are wearing clothes. Because motion can drive clothes attached to the human body loosely or tightly, we adopt a space-time analysis to mine the information across the posture variations. Using this information, we recover the human body, regardless of the effect of clothes, and measure the human body parameters accurately. Experimental results show that our system can perform more accurate parameter estimation on the human body than state-of-the-art methods. PMID:24064597

  7. Emotional contagion: dogs and humans show a similar physiological response to human infant crying.

    PubMed

    Yong, Min Hooi; Ruffman, Ted

    2014-10-01

    Humans respond to an infant crying with an increase in cortisol level and heightened alertness, a response interpreted as emotional contagion, a primitive form of empathy. Previous results are mixed when examining whether dogs might respond similarly to human distress. We examined whether domestic dogs, which have a long history of affiliation with humans, show signs of emotional contagion, testing canine (n=75) and human (n=74) responses to one of three auditory stimuli: a human infant crying, a human infant babbling, and computer-generated "white noise", with the latter two stimuli acting as controls. Cortisol levels in both humans and dogs increased significantly from baseline only after listening to crying. In addition, dogs showed a unique behavioral response to crying, combining submissiveness with alertness. These findings suggest that dogs experience emotional contagion in response to human infant crying and provide the first clear evidence of a primitive form of cross-species empathy. PMID:25452080

  8. A Mathematical Model of Human Semicircular Canal Geometry: A New Basis for Interpreting Vestibular Physiology

    PubMed Central

    Curthoys, Ian S.; Todd, Michael J.; Magnussen, John S.; Taubman, David S.; Aw, Swee T.; Halmagyi, G. Michael

    2009-01-01

    We report a precise, simple, and accessible method of mathematically measuring and modeling the three-dimensional (3D) geometry of semicircular canals (SCCs) in living humans. Knowledge of this geometry helps understand the development and physiology of SCC stimulation. We developed a framework of robust techniques that automatically and accurately reconstruct SCC geometry from computed tomography (CT) images and are directly validated using micro-CT as ground truth. This framework measures the 3D centroid paths of the bony SCCs allowing direct comparison and analysis between ears within and between subjects. An average set of SCC morphology is calculated from 34 human ears, within which other geometrical attributes such as nonplanarity, radius of curvature, and inter-SCC angle are examined, with a focus on physiological implications. These measurements have also been used to critically evaluate plane fitting techniques that reconcile many of the discrepancies in current SCC plane studies. Finally, we mathematically model SCC geometry using Fourier series equations. This work has the potential to reinterpret physiology and pathophysiology in terms of real individual 3D morphology. Electronic supplementary material The online version of this article (doi:10.1007/s10162-009-0195-6) contains supplementary material, which is available to authorized users. PMID:19949828

  9. Physiological activity of irradiated green tea polyphenol on the human skin.

    PubMed

    An, Bong-Jeun; Kwak, Jae-Hoon; Son, Jun-Ho; Park, Jung-Mi; Lee, Jin-Young; Park, Tae Soon; Kim, So-Yeun; Kim, Yeoung-Sun; Jo, Cheorun; Byun, Myung-Woo

    2005-01-01

    Physiological activity of irradiated green tea polyphenol on the human skin was investigated for further industrial application. The green tea polyphenol was separated and irradiated at 40 kGy by y-ray. For an anti-wrinkle effect, the collagenase inhibition effect was higher in the irradiated sample (65.3%) than that of the non-irradiated control (56.8%) at 200 ppm of the concentration (p < 0.05). Collagen biosynthesis rates using a human fibroblast were 19.4% and 16.3% in the irradiated and the non-irradiated polyphenols, respectively. The tyrosinase inhibition effect, which is related to the skin-whitening effect, showed a 45.2% and 42.9% in the irradiated and the non-irradiated polyphenols, respectively, at a 100 ppm level. A higher than 90% growth inhibition on skin cancer cells (SK-MEL-2 and G361) was demonstrated in both the irradiated and the non-irradiated polyphenols. Thus, the irradiation of green tea polyphenol did not change and even increased its anti-wrinkle, skin-whitening and anticancer effects on the human skin. The results indicated that irradiated green tea polyphenol can be used as a natural ingredient with excellent physiological functions for the human skin through cosmetic or food composition. PMID:16173528

  10. Cortisol as a Biomarker of Stress in Term Human Labor: Physiological and Methodological Issues

    PubMed Central

    Newton, Edward R.; Tanner, Charles J.; Heitkemper, Margaret M.

    2013-01-01

    Literature on the use of plasma cortisol to quantify psychophysiological stress in humans is extensive. However, in parturition at term gestation the use of cortisol as a biomarker of stress is particularly complex. Plasma cortisol levels increase as labor progresses. This increase seems to be important for maintenance of maternal/fetal wellbeing and facilitation of normal labor progress. Unique physiological and methodological issues involved in the use of cortisol as a biomarker of stress in labor present challenges for researchers. This review examines these issues, suggests mixed methods and within-subject repeated measures designs, and offers recommendations for assay procedures for parturient sampling. Documentation of clinical interventions and delivery outcomes may elucidate relationships among psychophysiological stressors, cortisol and normal labor progress. With attention to these methodological issues, analysis of plasma cortisol may lead to clinical interventions that support normal labor physiology. PMID:23338011

  11. Critical review evaluating the pig as a model for human nutritional physiology.

    PubMed

    Roura, Eugeni; Koopmans, Sietse-Jan; Lallès, Jean-Paul; Le Huerou-Luron, Isabelle; de Jager, Nadia; Schuurman, Teun; Val-Laillet, David

    2016-06-01

    The present review examines the pig as a model for physiological studies in human subjects related to nutrient sensing, appetite regulation, gut barrier function, intestinal microbiota and nutritional neuroscience. The nutrient-sensing mechanisms regarding acids (sour), carbohydrates (sweet), glutamic acid (umami) and fatty acids are conserved between humans and pigs. In contrast, pigs show limited perception of high-intensity sweeteners and NaCl and sense a wider array of amino acids than humans. Differences on bitter taste may reflect the adaptation to ecosystems. In relation to appetite regulation, plasma concentrations of cholecystokinin and glucagon-like peptide-1 are similar in pigs and humans, while peptide YY in pigs is ten to twenty times higher and ghrelin two to five times lower than in humans. Pigs are an excellent model for human studies for vagal nerve function related to the hormonal regulation of food intake. Similarly, the study of gut barrier functions reveals conserved defence mechanisms between the two species particularly in functional permeability. However, human data are scant for some of the defence systems and nutritional programming. The pig model has been valuable for studying the changes in human microbiota following nutritional interventions. In particular, the use of human flora-associated pigs is a useful model for infants, but the long-term stability of the implanted human microbiota in pigs remains to be investigated. The similarity of the pig and human brain anatomy and development is paradigmatic. Brain explorations and therapies described in pig, when compared with available human data, highlight their value in nutritional neuroscience, particularly regarding functional neuroimaging techniques. PMID:27176552

  12. The physiological responses of Vallisneria natans to epiphytic algae with the increase of N and P concentrations in water bodies.

    PubMed

    Song, Yu-Zhi; Wang, Jin-Qi; Gao, Yong-Xia; Xie, Xue-Jian

    2015-06-01

    To reveal the mechanism of submerged plants decline in progressively eutrophicated freshwaters, physiological responses of Vallisneria natans to epiphytic algae were studied in simulation lab by measuring plant physiological indexes of chlorophyll content, malondialdehyde (MDA) content, and superoxide dismutase (SOD) activity based on a 2 × 4 factorial design with two epiphytic conditions (with epiphytic algae and without) and four levels of N and P concentrations in water (N-P[mg.L(-1)]: 0.5, 0.05; 2.5, 0.25; 4.5, 0.45; 12.5, 1.25). Compared with control (non-presence of epiphytic algae), chlorophyll contents of V. natans were significantly decreased (p < 0.01) for the presence of epiphytic algae under any concentrations of N and P in water bodies. While the presence of epiphytic algae induced peroxidation of membrane lipids, MDA contents of V. natans had significantly increased (p < 0.05) by comparing with control. SOD activity significantly enhanced (p < 0.05) with the presence of epiphytic algae in the treatments of T2 and T3 in the whole culture process by comparing with control, sometimes reaching an extremely significant level (p < 0.01). However, in the treatments of T1 and T4, SOD activity had no obvious change with the presence of epiphytic algae (p < 0.05) by comparing with control. At the end of the experiment, the effects of epiphytic algae on chlorophyll content and SOD activity in the leaves of V. natans were increased at first and then decreased with the concentrations of N and P in water, and MDA content became higher with the increase of N and P. concentrations. Repeated measurement data testing showed that the effects of epiphytic algae on the chlorophyll content and MDA content and SOD activity were significant, respectively (p < 0.001), the effects of epiphytic algae were combining with effects of concentrations of N and P (p < 0.001), respectively, and their interaction (p < 0.001). Our observations

  13. Accelerated generation of human induced pluripotent stem cells with retroviral transduction and chemical inhibitors under physiological hypoxia

    SciTech Connect

    Shimada, Hidenori; Hashimoto, Yoshiya; Nakada, Akira; Shigeno, Keiji; Nakamura, Tatsuo

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer Very rapid generation of human iPS cells under optimized conditions. Black-Right-Pointing-Pointer Five chemical inhibitors under hypoxia boosted reprogramming. Black-Right-Pointing-Pointer We performed genome-wide DNA methylation analysis. -- Abstract: Induced pluripotent stem (iPS) cells are generated from somatic cells by the forced expression of a defined set of pluripotency-associated transcription factors. Human iPS cells can be propagated indefinitely, while maintaining the capacity to differentiate into all cell types in the body except for extra-embryonic tissues. This technology not only represents a new way to use individual-specific stem cells for regenerative medicine but also constitutes a novel method to obtain large amounts of disease-specific cells for biomedical research. Despite their great potential, the long reprogramming process (up to 1 month) remains one of the most significant challenges facing standard virus-mediated methodology. In this study, we report the accelerated generation of human iPS cells from adipose-derived stem (ADS) cells, using a new combination of chemical inhibitors under a setting of physiological hypoxia in conjunction with retroviral transduction of Oct4, Sox2, Klf4, and L-Myc. Under optimized conditions, we observed human embryonic stem (ES)-like cells as early as 6 days after the initial retroviral transduction. This was followed by the emergence of fully reprogrammed cells bearing Tra-1-81-positive and DsRed transgene-silencing properties on day 10. The resulting cell lines resembled human ES cells in many respects including proliferation rate, morphology, pluripotency-associated markers, global gene expression patterns, genome-wide DNA methylation states, and the ability to differentiate into all three of the germ layers, both in vitro and in vivo. Our method, when combined with chemical inhibitors under conditions of physiological hypoxia, offers a powerful tool for rapidly

  14. Development of a human physiologically based pharmacokinetic (PBPK) model for dermal permeability for lindane.

    PubMed

    Sawyer, Megan E; Evans, Marina V; Wilson, Charles A; Beesley, Lauren J; Leon, Lider S; Eklund, Chris R; Croom, Edward L; Pegram, Rex A

    2016-03-14

    Lindane is a neurotoxicant used for the treatment of lice and scabies present on human skin. Due to its pharmaceutical application, an extensive pharmacokinetic database exists in humans. Mathematical diffusion models allow for calculation of lindane skin permeability coefficients using human kinetic data obtained from in vitro and in vivo experimentation as well as a default compound-specific calculation based on physicochemical characteristics used in the absence of kinetic data. A dermal model was developed to describe lindane diffusion into the skin, where the skin compartment consisted of homogeneous dermal tissue. This study utilized Fick's law of diffusion along with chemical binding to protein and lipids to determine appropriate dermal absorption parameters which were then incorporated into a physiologically based pharmacokinetic (PBPK) model to describe in vivo kinetics. The estimation of permeability coefficients using chemical binding in combination with in vivo data demonstrates the advantages of combining physiochemical properties with a PBPK model to predict dermal absorption. PMID:26794662

  15. Quantitative Validation of a Human Body Finite Element Model Using Rigid Body Impacts.

    PubMed

    Vavalle, Nicholas A; Davis, Matthew L; Stitzel, Joel D; Gayzik, F Scott

    2015-09-01

    Validation is a critical step in finite element model (FEM) development. This study focuses on the validation of the Global Human Body Models Consortium full body average male occupant FEM in five localized loading regimes-a chest impact, a shoulder impact, a thoracoabdominal impact, an abdominal impact, and a pelvic impact. Force and deflection outputs from the model were compared to experimental traces and corridors scaled to the 50th percentile male. Predicted fractures and injury severity measures were compared to evaluate the model's injury prediction capabilities. The methods of ISO/TS 18571 were used to quantitatively assess the fit of model outputs to experimental force and deflection traces. The model produced peak chest, shoulder, thoracoabdominal, abdominal, and pelvis forces of 4.8, 3.3, 4.5, 5.1, and 13.0 kN compared to 4.3, 3.2, 4.0, 4.0, and 10.3 kN in the experiments, respectively. The model predicted rib and pelvic fractures related to Abbreviated Injury Scale scores within the ranges found experimentally all cases except the abdominal impact. ISO/TS 18571 scores for the impacts studied had a mean score of 0.73 with a range of 0.57-0.83. Well-validated FEMs are important tools used by engineers in advancing occupant safety. PMID:25739950

  16. Outdoor thermal physiology along human pathways: a study using a wearable measurement system.

    PubMed

    Nakayoshi, Makoto; Kanda, Manabu; Shi, Rui; de Dear, Richard

    2015-05-01

    An outdoor summer study on thermal physiology along subjects' pathways was conducted in a Japanese city using a unique wearable measurement system that measures all the relevant thermal variables: ambient temperature, humidity, wind speed (U) and short/long-wave radiation (S and L), along with some physio-psychological parameters: skin temperature (T skin), pulse rate, subjective thermal sensation and state of body motion. U, S and L were measured using a globe anemo-radiometer adapted use with pedestrian subjects. The subjects were 26 healthy Japanese adults (14 males, 12 females) ranging from 23 to 74 years in age. Each subject wore a set of instruments that recorded individual microclimate and physiological responses along a designated pedestrian route that traversed various urban textures. The subjects experienced varying thermal environments that could not be represented by fixed-point routine observational data. S fluctuated significantly reflecting the mixture of sunlit/shade distributions within complex urban morphology. U was generally low within urban canyons due to drag by urban obstacles such as buildings but the subjects' movements enhanced convective heat exchanges with the atmosphere, leading to a drop in T skin. The amount of sweating increased as standard effective temperature (SET*) increased. A clear dependence of sweating on gender and body size was found; males sweated more than females; overweight subjects sweated more than standard/underweight subjects. T skin had a linear relationship with SET* and a similarly clear dependence on gender and body size differences. T skin of the higher-sweating groups was lower than that of the lower-sweating groups, reflecting differences in evaporative cooling by perspiration. PMID:25011423

  17. Outdoor thermal physiology along human pathways: a study using a wearable measurement system

    NASA Astrophysics Data System (ADS)

    Nakayoshi, Makoto; Kanda, Manabu; Shi, Rui; de Dear, Richard

    2015-05-01

    An outdoor summer study on thermal physiology along subjects' pathways was conducted in a Japanese city using a unique wearable measurement system that measures all the relevant thermal variables: ambient temperature, humidity, wind speed ( U) and short/long-wave radiation ( S and L), along with some physio-psychological parameters: skin temperature ( T skin), pulse rate, subjective thermal sensation and state of body motion. U, S and L were measured using a globe anemo-radiometer adapted use with pedestrian subjects. The subjects were 26 healthy Japanese adults (14 males, 12 females) ranging from 23 to 74 years in age. Each subject wore a set of instruments that recorded individual microclimate and physiological responses along a designated pedestrian route that traversed various urban textures. The subjects experienced varying thermal environments that could not be represented by fixed-point routine observational data. S fluctuated significantly reflecting the mixture of sunlit/shade distributions within complex urban morphology. U was generally low within urban canyons due to drag by urban obstacles such as buildings but the subjects' movements enhanced convective heat exchanges with the atmosphere, leading to a drop in T skin. The amount of sweating increased as standard effective temperature (SET*) increased. A clear dependence of sweating on gender and body size was found; males sweated more than females; overweight subjects sweated more than standard/underweight subjects. T skin had a linear relationship with SET* and a similarly clear dependence on gender and body size differences. T skin of the higher-sweating groups was lower than that of the lower-sweating groups, reflecting differences in evaporative cooling by perspiration.

  18. AN EXAMPLE OF MODEL STRUCTURE DIFFERENCES USING SENSITIVITY ANALYSES IN PHYSIOLOGICALLY BASED PHARMACOKINETIC MODELS OF TRICHLOROETHYLENE IN HUMANS

    EPA Science Inventory

    Abstract Trichloroethylene (TCE) is an industrial chemical and an environmental contaminant. TCE and its metabolites may be carcinogenic and affect human health. Physiologically based pharmacokinetic (PBPK) models that differ in compartmentalization are developed for TCE metabo...

  19. Physiology of SLC12 transporters: lessons from inherited human genetic mutations and genetically engineered mouse knockouts

    PubMed Central

    Gagnon, Kenneth B.

    2013-01-01

    Among the over 300 members of the solute carrier (SLC) group of integral plasma membrane transport proteins are the nine electroneutral cation-chloride cotransporters belonging to the SLC12 gene family. Seven of these transporters have been functionally described as coupling the electrically silent movement of chloride with sodium and/or potassium. Although in silico analysis has identified two additional SLC12 family members, no physiological role has been ascribed to the proteins encoded by either the SLC12A8 or the SLC12A9 genes. Evolutionary conservation of this gene family from protists to humans confirms their importance. A wealth of physiological, immunohistochemical, and biochemical studies have revealed a great deal of information regarding the importance of this gene family to human health and disease. The sequencing of the human genome has provided investigators with the capability to link several human diseases with mutations in the genes encoding these plasma membrane proteins. The availability of bacterial artificial chromosomes, recombination engineering techniques, and the mouse genome sequence has simplified the creation of targeting constructs to manipulate the expression/function of these cation-chloride cotransporters in the mouse in an attempt to recapitulate some of these human pathologies. This review will summarize the three human disorders that have been linked to the mutation/dysfunction of the Na-Cl, Na-K-2Cl, and K-Cl cotransporters (i.e., Bartter's, Gitleman's, and Andermann's syndromes), examine some additional pathologies arising from genetically modified mouse models of these cotransporters including deafness, blood pressure, hyperexcitability, and epithelial transport deficit phenotypes. PMID:23325410

  20. Improved analysis of malondialdehyde in human body fluids.

    PubMed

    Jentzsch, A M; Bachmann, H; Fürst, P; Biesalski, H K

    1996-01-01

    The widely used TBA assay for lipid peroxidation was modified to minimize artefactual oxidative degradation of lipids during the assay. Formation of the TBA-MDA condensation product was studied with and without exclusion of oxygen, and the concentration effect of BHT addition was examined. Oxygen was depleted from the reaction mixture by extensive argon gassing. Exclusion of oxygen resulted in decreased TBARS production in plasma but not in standard solutions. High BHT concentrations resulted in a similar effect. At concentrations higher than 3 mmol/l BHT exclusion of oxygen had no additional effect. By measuring n-butanol extracts in a multititer plate reader this modified method was made suitable as a preliminary screening assay of human body fluids for lipid peroxidation. PMID:8746446

  1. The mechanism of aspirin reactions in the human body

    NASA Astrophysics Data System (ADS)

    Graves, Alan; di Ventra, Massimiliano; Sohlberg, Karl; Pantelides, Sokrates T.

    2001-03-01

    We report first-principles (density functional theory) calculations of possible reaction pathways for the break-up of aspirin that leads to pain relief in the human body. An aspirin molecule consists of an acetyl group attached to a salicylate. Upon entering a membrane protein known as COX, the aspirin molecule is pulled apart. The acetyl group of the aspirin molecule attaches to SER-530, a serine residue that is located near the entrance of the COX protein channel. The resulting acetyl-serine residue effectively forms a gate within the COX channel blocking certain fatty acids from reaching the protein active site where they are converted into prostaglandins, the molecules that are responsible for the sensation of pain. An important new finding is that the aspirin molecule undergoes a transformation prior to breaking up.

  2. Treatment model of dengue hemorrhagic fever infection in human body

    NASA Astrophysics Data System (ADS)

    Handayani, D.; Nuraini, N.; Primasari, N.; Wijaya, K. P.

    2014-03-01

    The treatment model of DHF presented in this paper involves the dynamic of five time-dependent compartments, i.e. susceptible, infected, free virus particle, immune cell, and haematocrit level. The treatment model is investigated based on normalization of haematocrit level, which is expressed as intravenous fluid infusion control. We analyze the stability of the disease free equilibrium and the endemic equilibrium. The numerical simulations will explain the dynamic of each compartment in human body. These results show particularly that infected compartment and free virus particle compartment are tend to be vanished in two weeks after the onset of dengue virus. However, these simulation results also show that without the treatment, the haematocrit level will decrease even though not up to the normal level. Therefore the effective haematocrit normalization should be done with the treatment control.

  3. Calculations of aspirin reaction mechanisms in the human body

    NASA Astrophysics Data System (ADS)

    Graves, Alan; Sohlberg, Karl; Pantelides, Sokrates T.

    1999-11-01

    We report quantum mechanical calculations of possible reaction pathways for the breakup of aspirin that lead to pain relief in the human body. Animations of the reactions will be shown. An aspirin molecule consists of an acetyl group attached to a salicylate. Upon entering a membrane protein known as COX, the aspirin molecule is pulled apart. The acetyl group of the aspirin molecule attaches to SER-530, a serine residue that is located near the entrance of the COX protein channel. The resulting acetyl-serine residue effectively forms a gate within the COX channel blocking certain fatty acids from reaching the protein active site where the fatty acids are converted into prostaglandins, the molecules that are responsible for inflammation and the sensation of pain.

  4. The human body as field of conflict between discourses.

    PubMed

    Kimsma, Gerrit K; Leeuwen, Evert van

    2005-01-01

    The approach to AIDS as a disease and a threat for social discrimination is used as an example to illustrate a conceptual thesis. This thesis is a claim that concerns what we call a medical issue or not, what is medicalised or needs to be demedicalised. In the friction between medicalisation and demedicalisation as discursive strategies the latter approach can only be effected through the employment of discourses or discursive strategies other than medicine, such as those of the law and of economics. These discourses each realise different values, promote a different subject, and have a different concept of man. The concept of discourse is briefly outlined against concepts such as the linear growth concept of science and the growth model of science as changes in paradigm. The issue of testing for AIDS shows a conflict between the medical and the legal discourse and illustrates the title of our contribution: the human body as field of conflict between discourses. PMID:16292608

  5. Earthsickness: circumnavigation and the terrestrial human body, 1520-1800.

    PubMed

    Chaplin, Joyce E

    2012-01-01

    From their distinctive experience of going around the world, maritime circumnavigators concluded that their characteristic disease, sea scurvy, must result from their being away from land too long, much longer than any other sailors. They offered their scorbutic bodies as proof that humans were terrestrial creatures, physically suited to the earthly parts of a terraqueous globe. That arresting claim is at odds with the current literature on the cultural implications of European expansion, which has emphasized early modern colonists' and travelers' fear of alien places, and has concluded that they had a small and restricted geographic imagination that fell short of the planetary consciousness associated with the nineteenth and twentieth centuries. But circumnavigators did conceive of themselves as actors on a planetary scale, as creatures adapted to all of the land on Earth, not just their places of origin. PMID:23263345

  6. Dynamic OCT for physiological functions of micro organs in human fingers

    NASA Astrophysics Data System (ADS)

    Haruna, Masamitsu; Ohmi, Masato; Ueda, Yoshihiro; Fuji, Toshie; Yamada, Akihiro; Saigusa, Hiroyuki; Kuwabara, Mitsuo

    2007-11-01

    OCT is a powerful tool for detection of physiological functions of micro organs underneath the human skin surface, besides the clinical application to ophthalmology, as recently demonstrated by the authors' group. In particular, dynamics of peripheral vessels and eccrin sweat glands can be observed clearly in the time-sequential OCT images. The physiological functions of these micro organs, sweating and blood circulation, are controlled by the skin sympathetic nerve in response to externally applied stress. In this paper, we present microscopically analytical results based on the dynamic OCT of the micro organs in human fingers. In sweating dynamics, it is found that a spiral sweat duct is expanded by abrupt increase of sweat due to application of stress to a volunteer, resulting in remarkable increase of the reflection light intensity of the spiral duct in OCT. Mental-stress-induced sweating in each eccrin sweat gland, therefore, is analyzed quantitatively. Furthermore, dynamic OCT observation of peripheral vessels is interesting. A small vein of a human finger is observed clearly by the TD-OCT, where the vein expands and contracts repeatedly even in the resting state for temperature control on the fingertip. A change in the cross-sectional area of the vein exceeds 80 % for a young volunteer. The dynamic OCT will allow us to propose novel diagnoses of excessive sweating and diseases related to the sympathetic nerve.

  7. Comparison of Biodynamic Responses in Standing and Seated Human Bodies

    NASA Astrophysics Data System (ADS)

    MATSUMOTO, Y.; GRIFFIN, M. J.

    2000-12-01

    The dynamic responses of the human body in a standing position and in a sitting position have been compared. The apparent mass and transmissibilities to the head, six locations along the spine, and the pelvis were measured with eight male subjects exposed to vertical whole-body vibration. In both postures, the principal resonance in the apparent mass occurred in the range 5-6 Hz, with slightly higher frequencies and lower apparent mass in the standing posture. There was greater transmission of vertical vibration to the pelvis and the lower spine and greater relative motion within the lower spine in the standing posture than in the sitting posture at the principal resonance and at higher frequencies. Transmissibilities from the supporting surface (floor or seat) to the thoracic region had similar magnitudes for both standing and sitting subjects. The lumbar spine has less lordosis and may be more compressed and less flexible in the sitting posture than in the standing posture. This may have reduced the relative motions between lumbar vertebrae and both the supporting vibrating surface and the other vertebrae in the sitting posture. The characteristics of the vibration transmitted to the pelvis may have differed in the two postures due to different transmission paths. Increased forward rotation of the pelvis in the standing posture may have caused the differences in responses of the pelvis and the lower spine that were observed between the two postures.

  8. Study of human phonation in a full-body domain

    NASA Astrophysics Data System (ADS)

    Saurabh, Shakti; Bodony, Daniel

    2015-11-01

    The generation and propagation of the human voice is studied in two-dimensions using a full-body domain, using direct numerical simulation. The fluid/air in the vocal tract is modeled as a compressible and viscous fluid interacting with the non-linear, viscoelastic vocal folds (VF). The VF tissue material properties are multi-layered, with varying stiffness, and a finite-strain model is utilized and implemented in a quadratic finite element code. The fluid-solid domains are coupled through a boundary-fitted interface and utilize a Poisson equation-based mesh deformation method. The full-body domain includes the near VF region, the vocal tract, a simplified model of the soft palate and mouth, and extends out into the acoustic far-field. A new kind of inflow boundary condition based upon a quasi-one-dimensional formulation with constant sub-glottal volume velocity, which is linked to the VF movement, has been adopted. The sound pressure levels (SPL) measured are realistic and we analyze their connection to the VF dynamics and glottal and vocal tract geometries. Supported by the National Science Foundation (CAREER award number 1150439).

  9. Phytochemicals in the Control of Human Appetite and Body Weight

    PubMed Central

    Tucci, Sonia A.

    2010-01-01

    Since obesity has grown to epidemic proportions, its effective management is a very important clinical issue. Despite the great amount of scientific effort that has been put into understanding the mechanisms that lead to overconsumption and overweight, at the moment very few approaches to weight management are effective in the long term. On the other hand, modern society is also affected by the growing incidence of eating disorders on the other side of the spectrum such as anorexia and bulimia nervosa which are equally difficult to treat. This review will try to summarise the main findings available in the literature regarding the effect of plants or plant extracts (phytochemicals) on human appetite and body weight. The majority of plant extracts are not single compounds but rather a mixture of different molecules, therefore their mechanism of action usually targets several systems. In addition, since some cellular receptors tend to be widely distributed, sometimes a single molecule can have a widespread effect. This review will attempt to describe the main phytochemicals that have been suggested to affect the homeostatic mechanisms that influence intake and body weight. Clinical data will be summarised and scientific evidence will be reviewed.

  10. The biokinetics of ruthenium in the human body

    SciTech Connect

    Leggett, Richard Wayne

    2011-01-01

    The biokinetics of ruthenium (Ru) in the human body is of interest due mainly to the potential for occupational or environmental exposure to 106Ru (T1/2 = 373.6 d) and 103Ru (T1/2 = 39.3 d), which typically represent a significant portion of the fission products in a reactor inventory. During reactor operations or nuclear fuel reprocessing these ruthenium isotopes may be present as ruthenium tetroxide (RuO4) vapor, a highly mobile form of ruthenium that has been involved in a number of cases of accidental exposure to 106Ru or 103Ru. This paper summarizes the biokinetic database for ruthenium and proposes a new respiratory model for inhaled RuO4 vapor, a new biokinetic for systemic (absorbed) ruthenium, and material-specific gastrointestinal absorption fractions for ruthenium. The proposed respiratory model for RuO4 differs from the current ICRP model mainly in that it depicts slower clearance of deposited activity from the respiratory tract and lower absorption to blood than depicted in the current ICRP model. The proposed systemic biokinetic model depicts more realistic paths of movement of absorbed ruthenium in the body than the current ICRP model and, in contrast to the present model, a less uniform distribution of systemic activity. Implications of the proposed models with regard to inhalation and ingestion dose coefficients for 106Ru are examined.

  11. Measurement of caesium-137 in the human body using a whole body counter

    NASA Astrophysics Data System (ADS)

    Elessawi, Elkhadra Abdulmula

    Gamma radiation in the environment is mainly due to naturally occurring radionuclides. However, there is also a contribution from anthropogenic radionuclides such as 137Cs which originate from nuclear fission processes. Since 1986, the accident at the Chernobyl power plant has been a significant source of artificial environmental radioactivity. In order to assess the radiological impact of these radionuclides, it is necessary to measure their activities in samples drawn from the environment and in plants and animals including human populations. The whole body counter (WBC) at the University Hospital of Wales in Cardiff makes in vivo measurements of gamma emitting radionuclides using a scanning ring of six large-volume thallium-doped sodium iodide (Nal(Tl)) scintillation detectors. In this work the WBC was upgraded by the addition of two high purity germanium (HPGe) detectors. The performance and suitability of the detection systems were evaluated by comparing the detection limits for Cs. Sensitivities were measured using sources of known activity in a water filled anthropomorphic phantom and theoretical minimum detectable count-rates were estimated from phantom background pulse height spectra. The theoretical minimum detectable activity was about 24 Bq for the combination of six Nal(Tl) detectors whereas for the individual HPGe detectors it was 64 Bq and 65 Bq, despite the much improved energy resolution Activities of 137Cs in the human body between 1993 and 2007 were estimated from the background Nal(Tl) spectra of 813 patients and compared with recent measurements in 14 volunteers. The body burden of Cs in Cardiff patients increased from an average of about 60 Bq in the early and mid 1990s to a maximum of about 100 Bq in 2000. By 2007 it had decreased to about 40 Bq. This latter value was similar to that of Cardiff residents at the time of the Chernobyl accident and to that of the volunteers measured in 2007 (51 Bq). However, it was less than the mean activity of

  12. Stone formation and calcification by nanobacteria in the human body

    NASA Astrophysics Data System (ADS)

    Ciftcioglu, Neva; Bjorklund, Michael; Kajander, E. Olavi

    1998-07-01

    The formation of discrete and organized inorganic crystalline structures within macromolecular extracellular matrices is a widespread biological phenomenon generally referred to as biomineralization. Recently, bacteria have been implicated as factors in biogeochemical cycles for formation of many minerals in aqueous sediments. We have found nanobacterial culture systems that allow for reproducible production of apatite calcification in vitro. Depending on the culture conditions, tiny nanocolloid-sized particles covered with apatite, forming various size of aggregates and stones were observed. In this study, we detected the presence of nanobacteria in demineralized trilobit fossil, geode, apatite, and calcite stones by immunofluorescence staining. Amethyst and other quartz stones, and chalk gave negative results. Microorganisms are capable of depositing apatite outside the thermodynamic equilibrium in sea water. We bring now evidence that this occurs in the human body as well. Previously, only struvite kidney stones composed of magnesium ammonium phosphate and small amounts of apatite have been regarded as bacteria related. 90 percent of demineralized human kidney stones now screened, contained nanobacteria. At least three different distribution patterns of nanobacteria were conditions, and human kidney stones that are formed from small apatite units. Prerequisites for the formation of kidney stones are the supersaturation of urine and presence of nidi for crystallization. Nanobacteria are important nidi and their presence might be of special interest in space flights where supersaturation of urine is present due to the loss of bone. Furthermore, we bring evidence that nanobacteria may act as crystallization nidi for the formation of biogenic apatite structures in tissue calcification found in e.g., atherosclerotic plaques, extensive metastatic and tumoral calcification, acute periarthritis, malacoplakia, and malignant diseases. In nanaobacteria-infected fibroblasts

  13. Qigong as a Traditional Vegetative Biofeedback Therapy: Long-Term Conditioning of Physiological Mind-Body Effects

    PubMed Central

    Matos, Luís Carlos; Sousa, Cláudia Maria; Gonçalves, Mário; Gabriel, Joaquim; Machado, Jorge; Greten, Henry Johannes

    2015-01-01

    A contemporary understanding of Chinese Medicine (CM) regards CM diagnosis as a functional vegetative state that may be treated by vegetative reflex therapies such as acupuncture. Within this context, traditional mind-body exercises such as Qigong can be understood as an attempt to enhance physiological proprioception, by combining a special state of “awareness” with posture, movement, and breath control. We have formerly trained young auditing flutists in “White Ball” Qigong to minimize anxiety-induced cold hands and lower anxiety-induced heart rate. Functional changes occurred 2–5 min after training and were observed over the whole training program, allowing the children to control their symptoms. In our current work, we report that warm fingers and calm hearts could be induced by the children even without Qigong exercises. Thus, these positive changes once induced and “conditioned” vegetatively were stable after weeks of training. This may show the mechanism by which Qigong acts as a therapeutic measure in disease: positive vegetative pathways may be activated instead of dysfunctional functional patterns. The positive vegetative patterns then may be available in critical stressful situations. Qigong exercise programs may therefore be understood as an ancient vegetative biofeedback exercise inducing positive vegetative functions which are added to the individual reactive repertoire. PMID:26137485

  14. Qigong as a Traditional Vegetative Biofeedback Therapy: Long-Term Conditioning of Physiological Mind-Body Effects.

    PubMed

    Matos, Luís Carlos; Sousa, Cláudia Maria; Gonçalves, Mário; Gabriel, Joaquim; Machado, Jorge; Greten, Henry Johannes

    2015-01-01

    A contemporary understanding of Chinese Medicine (CM) regards CM diagnosis as a functional vegetative state that may be treated by vegetative reflex therapies such as acupuncture. Within this context, traditional mind-body exercises such as Qigong can be understood as an attempt to enhance physiological proprioception, by combining a special state of "awareness" with posture, movement, and breath control. We have formerly trained young auditing flutists in "White Ball" Qigong to minimize anxiety-induced cold hands and lower anxiety-induced heart rate. Functional changes occurred 2-5 min after training and were observed over the whole training program, allowing the children to control their symptoms. In our current work, we report that warm fingers and calm hearts could be induced by the children even without Qigong exercises. Thus, these positive changes once induced and "conditioned" vegetatively were stable after weeks of training. This may show the mechanism by which Qigong acts as a therapeutic measure in disease: positive vegetative pathways may be activated instead of dysfunctional functional patterns. The positive vegetative patterns then may be available in critical stressful situations. Qigong exercise programs may therefore be understood as an ancient vegetative biofeedback exercise inducing positive vegetative functions which are added to the individual reactive repertoire. PMID:26137485

  15. Physiologic response of human brain death and the use of vasopressin for successful organ transplantation.

    PubMed

    Nakagawa, Kazuma; Tang, Julin F

    2011-03-01

    The dynamic physiologic response of human brain death and the impact of vasopressin on successful organ transplantation is reported. A 60-year-old woman was admitted to the intensive care unit after severe traumatic brain injury resulting in brain death. Initial Cushing reflex was followed by a precipitous decrease in systemic blood pressure that was refractory to the alpha-agonist phenylephrine. After intravenous vasopressin was given, hemodynamic stability was restored and maintained until successful organ transplantation. Vasopressin, a catecholamine-sparing vasopressor and antidiuretic agent, may be an effective agent in the treatment of refractory hypotension after brain death prior to organ transplantation. PMID:21377081

  16. Visual Coding of Human Bodies: Perceptual Aftereffects Reveal Norm-Based, Opponent Coding of Body Identity

    ERIC Educational Resources Information Center

    Rhodes, Gillian; Jeffery, Linda; Boeing, Alexandra; Calder, Andrew J.

    2013-01-01

    Despite the discovery of body-selective neural areas in occipitotemporal cortex, little is known about how bodies are visually coded. We used perceptual adaptation to determine how body identity is coded. Brief exposure to a body (e.g., anti-Rose) biased perception toward an identity with opposite properties (Rose). Moreover, the size of this…

  17. Selective attention reduces physiological noise in the external ear canals of humans. I: auditory attention.

    PubMed

    Walsh, Kyle P; Pasanen, Edward G; McFadden, Dennis

    2014-06-01

    In this study, a nonlinear version of the stimulus-frequency OAE (SFOAE), called the nSFOAE, was used to measure cochlear responses from human subjects while they simultaneously performed behavioral tasks requiring, or not requiring, selective auditory attention. Appended to each stimulus presentation, and included in the calculation of each nSFOAE response, was a 30-ms silent period that was used to estimate the level of the inherent physiological noise in the ear canals of our subjects during each behavioral condition. Physiological-noise magnitudes were higher (noisier) for all subjects in the inattention task, and lower (quieter) in the selective auditory-attention tasks. These noise measures initially were made at the frequency of our nSFOAE probe tone (4.0 kHz), but the same attention effects also were observed across a wide range of frequencies. We attribute the observed differences in physiological-noise magnitudes between the inattention and attention conditions to different levels of efferent activation associated with the differing attentional demands of the behavioral tasks. One hypothesis is that when the attentional demand is relatively great, efferent activation is relatively high, and a decrease in the gain of the cochlear amplifier leads to lower-amplitude cochlear activity, and thus a smaller measure of noise from the ear. PMID:24732069

  18. Selective attention reduces physiological noise in the external ear canals of humans. II: visual attention.

    PubMed

    Walsh, Kyle P; Pasanen, Edward G; McFadden, Dennis

    2014-06-01

    Human subjects performed in several behavioral conditions requiring, or not requiring, selective attention to visual stimuli. Specifically, the attentional task was to recognize strings of digits that had been presented visually. A nonlinear version of the stimulus-frequency otoacoustic emission (SFOAE), called the nSFOAE, was collected during the visual presentation of the digits. The segment of the physiological response discussed here occurred during brief silent periods immediately following the SFOAE-evoking stimuli. For all subjects tested, the physiological-noise magnitudes were substantially weaker (less noisy) during the tasks requiring the most visual attention. Effect sizes for the differences were >2.0. Our interpretation is that cortico-olivo influences adjusted the magnitude of efferent activation during the SFOAE-evoking stimulation depending upon the attention task in effect, and then that magnitude of efferent activation persisted throughout the silent period where it also modulated the physiological noise present. Because the results were highly similar to those obtained when the behavioral conditions involved auditory attention, similar mechanisms appear to operate both across modalities and within modalities. Supplementary measurements revealed that the efferent activation was spectrally global, as it was for auditory attention. PMID:24732070

  19. Selective attention reduces physiological noise in the external ear canals of humans. I: Auditory attention

    PubMed Central

    Walsh, Kyle P.; Pasanen, Edward G.; McFadden, Dennis

    2014-01-01

    In this study, a nonlinear version of the stimulus-frequency OAE (SFOAE), called the nSFOAE, was used to measure cochlear responses from human subjects while they simultaneously performed behavioral tasks requiring, or not requiring, selective auditory attention. Appended to each stimulus presentation, and included in the calculation of each nSFOAE response, was a 30-ms silent period that was used to estimate the level of the inherent physiological noise in the ear canals of our subjects during each behavioral condition. Physiological-noise magnitudes were higher (noisier) for all subjects in the inattention task, and lower (quieter) in the selective auditory-attention tasks. These noise measures initially were made at the frequency of our nSFOAE probe tone (4.0 kHz), but the same attention effects also were observed across a wide range of frequencies. We attribute the observed differences in physiological-noise magnitudes between the inattention and attention conditions to different levels of efferent activation associated with the differing attentional demands of the behavioral tasks. One hypothesis is that when the attentional demand is relatively great, efferent activation is relatively high, and a decrease in the gain of the cochlear amplifier leads to lower-amplitude cochlear activity, and thus a smaller measure of noise from the ear. PMID:24732069

  20. Design and fabrication of a sensor integrated MEMS/NANO-skin system for human physiological response measurement

    NASA Astrophysics Data System (ADS)

    Leng, Hongjie; Lin, Yingzi

    2010-04-01

    Human state in human-machine systems highly affects the system performance, and should be monitored. Physiological cues are more suitable for monitoring the human state in human-machine system. This study was focused on developing a new sensing system, i.e. NANO-Skin, to non-intrusively measure physiological cues from human-machine contact surfaces for human state recognition. The first part was to analyze the relation between human state and physiological cues. Generally, heart rate, skin conductance, skin temperature, operating force, blood alcohol concentration, sweat rate, and electromyography have close relation with human state, and can be measured from human skin. The second part was to compare common sensors, MEMS sensors, and NANO sensors. It was found that MEMS sensors and NANO sensors can offer unique contributions to the development of NANO-Skin. The third part was to discuss the design and manufacture of NANO-Skin. The NANO-Skin involves five components, the flexible substrate, sensors, special integrated circuit, interconnection between sensors and special integrated circuit, and protection layer. Experiments were performed to verify the measurement accuracy of NANO-Skin. It is feasible to use NANO-Skins to non-intrusively measure physiological cues from human-machine contact surfaces for human state recognition.

  1. Physiological cognitive state assessment: applications for designing effective human-machine systems.

    PubMed

    Estepp, Justin R; Christensen, James C

    2011-01-01

    Significant growth in the field of neuroscience has occurred over the last decade such that new application areas for basic research techniques are opening up to practitioners in many other areas. Of particular interest to many is the principle of neuroergonomics, by which the traditional work in neuroscience and its related topics can be applied to non-traditional areas such as human-machine system design. While work in neuroergonomics certainly predates the use of the term in the literature (previously identified by others as applied neuroscience, operational neuroscience, etc.), there is great promise in the larger framework that is represented by the general context of the terminology. Here, we focus on the very specific concept that principles in brain-computer interfaces, neural prosthetics and the larger realm of machine learning using physiological inputs can be applied directly to the design and implementation of augmented human-machine systems. Indeed, work in this area has been ongoing for more than 25 years with very little cross-talk and collaboration between clinical and applied researchers. We propose that, given increased interest in augmented human-machine systems based on cognitive state, further progress will require research in the same vein as that being done in the aforementioned communities, and that all researchers with a vested interest in physiologically-based machine learning techniques can benefit from increased collaboration. We thereby seek to describe the current state of cognitive state assessment in human-machine systems, the problems and challenges faced, and the tightly-coupled relationship with other research areas. This supports the larger work of the Cognitive State Assessment 2011 Competition by setting the stage for the purpose of the session by showing the need to increase research in the machine learning techniques used by practitioners of augmented human-machine system design. PMID:22255837

  2. Animal models and their importance to human physiological responses in microgravity

    NASA Technical Reports Server (NTRS)

    Tipton, C. M.

    1996-01-01

    Two prominent theories to explain the physiological effects of microgravity relate to the cascade of changes associated with the cephalic shifts of fluids and the absence of tissue deformation forces. One-g experiments for humans used bed rest and the head-down tilt (HDT) method, while animal experiments have been conducted using the tail-suspended, head-down, and hindlimbs non-weightbearing model. Because of the success of the HDT approach with rats to simulate the gravitational effects on the musculoskeletal system exhibited by humans, the same model has been used to study the effects of gravity on the cardiopulmonary systems of humans and other vertebrates. Results to date indicate the model is effective in producing comparable changes associated with blood volume, erythropoiesis, cardiac mass, baroreceptor responsiveness, carbohydrate metabolism, post-flight VO2max, and post-flight cardiac output during exercise. Inherent with these results is the potential of the model to be useful in investigating responsible mechanisms. The suspension model has promise in understanding the capillary blood PO2 changes in space as well as the arterial PO2 changes in subjects participating in a HDT experiment. However, whether the model can provide insights on the up-or-down regulation of adrenoreceptors remains to be determined, and many investigators believe the HDT approach should not be followed to study gravitational influences on pulmonary function in either humans or animals. It was concluded that the tail-suspended animal model had sufficient merit to study in-flight and post-flight human physiological responses and mechanisms.

  3. Building "Bob": A Project Exploring the Human Body at Western Illinois University Preschool Center

    ERIC Educational Resources Information Center

    Brouette, Scott

    2008-01-01

    When the children at Western Illinois University Preschool Center embarked on a study of human bodies, they decided to build a life-size model of a body, organ by organ from the inside out, to represent some of the things they were learning. This article describes the building of "Bob," the human body model, highlighting the children's problem…

  4. Fretting behavior of NiTi shape memory alloy against long bone in the imitated human physiological solution

    NASA Astrophysics Data System (ADS)

    Yin, Y.; Xu, Y. T.; Xia, T. D.; Da, G. Z.

    2007-07-01

    The environment of orthopaedic implants sometimes induces vibrations at the contact of the modular prostheses components. In this paper the fretting behavior of NiTi SMAs against human bones in the imitated human physiological solution was studied at various displacement amplitudes and Ph value. Surface micrograph after fretting was observed by MEF3 microscope. Appearance of fretting scar was measured by 2206 roughness tester. The result shows that the friction coefficient between the bone and NiTi SMAs pairs declined due to the lubrication effect of Hank's solution, and which increased when Ph value of fluid was not 7.2 due to the corrosion. So the friction coefficient at acid and alkali Hank's solution is higher than those at the neutral solution and ambient air condition. Generally speaking, the friction coefficient between the bone and NiTi SMAs tend to be stable with the increasing amplitude at all test conditions. It is because that the surface was oxidized to restrain the forming of wear debris and the further development of fretting scars. Although the length and width of the wear scars in simulation body fluid are smaller than that at ambient air condition, the surface of NiTi SMAs damaged is characterized by deep scratches with debris particles within the contact area. Fretting regime of NiTi/bones pairs exhibits the mixed regime at ambient air condition and the slip regime in the Hank's solution.

  5. Relationship between human physiological parameters and geomagnetic variations of solar origin

    NASA Astrophysics Data System (ADS)

    Dimitrova, S.

    Results presented concern influence of increased geomagnetic activity on some human physiological parameters. The blood pressure and heart rate of 86 volunteers were measured on working days in autumn 2001 (01/10 09/11) and in spring 2002 (08/04 28/05). These periods were chosen because of maximal expected geomagnetic activity. Altogether 2799 recordings were obtained and analysed. Questionnaire information about subjective psycho-physiological complaints was also gathered. MANOVA was employed to check the significance of the influence of three factors on the physiological parameters under consideration. The factors were the following: (1) planetary geomagnetic activity level estimated by Ap-index and divided into five levels; (2) gender males and females; (3) blood pressure degree persons in the group examined were divided into hypotensive, normotensive and hypertensive. Post hoc analysis was performed to elicit the significance of differences in the factors’ levels. The average arterial blood pressure of the group was found to increase significantly with the increase of geomagnetic activity level. The average increment of systolic and diastolic blood pressure of the group examined reached 9%. This effect was present irrespectively of gender. Results obtained suppose that hypertensive persons have the highest sensitivity and the hypotensive persons have the lowest sensitivity of the arterial blood pressure to increase of geomagnetic activity. The results did not show significant changes in the heart rate. The percentage of the persons who reported subjective psycho-physiological complaints was also found to increase significantly with the geomagnetic activity increase and the highest sensitivity was revealed for the hypertensive females.

  6. Sex Differences in Human Fatigability: Mechanisms and Insight to Physiological Responses

    PubMed Central

    Hunter, Sandra K.

    2014-01-01

    Sex-related differences in physiology and anatomy are responsible for profound differences in neuromuscular performance and fatigability between men and women. Women are usually less fatigable than men for similar intensity isometric fatiguing contractions. This sex difference in fatigability, however, is task specific because different neuromuscular sites will be stressed when the requirements of the task are altered, and the stress on these sites can differ for men and women. Task variables that can alter the sex difference in fatigue include the type, intensity and speed of contraction, the muscle group assessed, and the environmental conditions. Physiological mechanisms that are responsible for sex-based differences in fatigability may include activation of the motor neuron pool from cortical and subcortical regions, synaptic inputs to the motor neuron pool via activation of metabolically-sensitive small afferent fibres in the muscle, muscle perfusion, and skeletal muscle metabolism and fibre type properties. Non-physiological factors such as the sex bias of studying more males than females in human and animal experiments can also mask a true understanding of the magnitude and mechanisms of sex-based differences in physiology and fatigability. Despite recent developments, there is a tremendous lack of understanding of sex differences in neuromuscular function and fatigability, the prevailing mechanisms and the functional consequences. This review emphasises the need to understand sex-based differences in fatigability in order to shed light on the benefits and limitations that fatigability can exert for men and women during daily tasks, exercise performance, training and rehabilitation in both health and disease. PMID:24433272

  7. Exercise and gene expression: physiological regulation of the human genome through physical activity

    PubMed Central

    Booth, Frank W; Chakravarthy, Manu V; Spangenburg, Espen E

    2002-01-01

    The current human genome was moulded and refined through generations of time. We propose that the basic framework for physiologic gene regulation was selected during an era of obligatory physical activity, as the survival of our Late Palaeolithic (50 000–10 000 BC) ancestors depended on hunting and gathering. A sedentary lifestyle in such an environment probably meant elimination of that individual organism. The phenotype of the present day Homo sapiens genome is much different from that of our ancient ancestors, primarily as a consequence of expressing evolutionarily programmed Late Palaeolithic genes in an environment that is predominantly sedentary. In this sense, our current genome is maladapted, resulting in abnormal gene expression, which in turn frequently manifests itself as clinically overt disease. We speculate that some of these genes still play a role in survival by causing premature death from chronic diseases produced by physical inactivity. We also contend that the current scientific evidence supports the notion that disruptions in cellular homeostasis are diminished in magnitude in physically active individuals compared with sedentary individuals due to the natural selection of gene expression that supports the physically active lifestyle displayed by our ancestors. We speculate that genes evolved with the expectation of requiring a certain threshold of physical activity for normal physiologic gene expression, and thus habitual exercise in sedentary cultures restores perturbed homeostatic mechanisms towards the normal physiological range of the Palaeolithic Homo sapiens. This hypothesis allows us to ask the question of whether normal physiological values change as a result of becoming sedentary. In summary, in sedentary cultures, daily physical activity normalizes gene expression towards patterns established to maintain the survival in the Late Palaeolithic era. PMID:12205177

  8. Development of a physiologically based pharmacokinetic model for assessment of human exposure to bisphenol A.

    PubMed

    Yang, Xiaoxia; Doerge, Daniel R; Teeguarden, Justin G; Fisher, Jeffrey W

    2015-12-15

    A previously developed physiologically based pharmacokinetic (PBPK) model for bisphenol A (BPA) in adult rhesus monkeys was modified to characterize the pharmacokinetics of BPA and its phase II conjugates in adult humans following oral ingestion. Coupled with in vitro studies on BPA metabolism in the liver and the small intestine, the PBPK model was parameterized using oral pharmacokinetic data with deuterated-BPA (d6-BPA) delivered in cookies to adult humans after overnight fasting. The availability of the serum concentration time course of unconjugated d6-BPA offered direct empirical evidence for the calibration of BPA model parameters. The recalibrated PBPK adult human model for BPA was then evaluated against published human pharmacokinetic studies with BPA. A hypothesis of decreased oral uptake was needed to account for the reduced peak levels observed in adult humans, where d6-BPA was delivered in soup and food was provided prior to BPA ingestion, suggesting the potential impact of dosing vehicles and/or fasting on BPA disposition. With the incorporation of Monte Carlo analysis, the recalibrated adult human model was used to address the inter-individual variability in the internal dose metrics of BPA for the U.S. general population. Model-predicted peak BPA serum levels were in the range of pM, with 95% of human variability falling within an order of magnitude. This recalibrated PBPK model for BPA in adult humans provides a scientific basis for assessing human exposure to BPA that can serve to minimize uncertainties incurred during extrapolations across doses and species. PMID:26522835

  9. Mapping implied body actions in the human motor system.

    PubMed

    Urgesi, Cosimo; Moro, Valentina; Candidi, Matteo; Aglioti, Salvatore M

    2006-07-26

    The human visual system is highly tuned to perceive actual motion as well as to extrapolate dynamic information from static pictures of objects or creatures captured in the middle of motion. Processing of implied motion activates higher-order visual areas that are also involved in processing biological motion. Imagery and observation of actual movements performed by others engenders selective activation of motor and premotor areas that are part of a mirror-neuron system matching action observation and execution. By using single-pulse transcranial magnetic stimulation, we found that the mere observation of static snapshots of hands suggesting a pincer grip action induced an increase in corticospinal excitability as compared with observation of resting, relaxed hands, or hands suggesting a completed action. This facilitatory effect was specific for the muscle that would be activated during actual execution of the observed action. We found no changes in responsiveness of the tested muscles during observation of nonbiological entities with (e.g., waterfalls) or without (e.g., icefalls) implied motion. Thus, extrapolation of motion information concerning human actions induced a selective activation of the motor system. This indicates that overlapping motor regions are engaged in the visual analysis of physical and implied body actions. The absence of motor evoked potential modulation during observation of end posture stimuli may indicate that the observation-execution matching system is preferentially activated by implied, ongoing but not yet completed actions. PMID:16870739

  10. Altered serotonin physiology in human breast cancers favors paradoxical growth and cell survival

    PubMed Central

    2009-01-01

    Introduction The breast microenvironment can either retard or accelerate the events associated with progression of latent cancers. However, the actions of local physiological mediators in the context of breast cancers are poorly understood. Serotonin (5-HT) is a critical local regulator of epithelial homeostasis in the breast and other organs. Herein, we report complex alterations in the intrinsic mammary gland serotonin system of human breast cancers. Methods Serotonin biosynthetic capacity was analyzed in human breast tumor tissue microarrays using immunohistochemistry for tryptophan hydroxylase 1 (TPH1). Serotonin receptors (5-HT1-7) were analyzed in human breast tumors using the Oncomine database. Serotonin receptor expression, signal transduction, and 5-HT effects on breast cancer cell phenotype were compared in non-transformed and transformed human breast cells. Results In the context of the normal mammary gland, 5-HT acts as a physiological regulator of lactation and involution, in part by favoring growth arrest and cell death. This tightly regulated 5-HT system is subverted in multiple ways in human breast cancers. Specifically, TPH1 expression undergoes a non-linear change during progression, with increased expression during malignant progression. Correspondingly, the tightly regulated pattern of 5-HT receptors becomes dysregulated in human breast cancer cells, resulting in both ectopic expression of some isoforms and suppression of others. The receptor expression change is accompanied by altered downstream signaling of 5-HT receptors in human breast cancer cells, resulting in resistance to 5-HT-induced apoptosis, and stimulated proliferation. Conclusions Our data constitutes the first report of direct involvement of 5-HT in human breast cancer. Increased 5-HT biosynthetic capacity accompanied by multiple changes in 5-HT receptor expression and signaling favor malignant progression of human breast cancer cells (for example, stimulated proliferation

  11. RF Device for Acquiring Images of the Human Body

    NASA Technical Reports Server (NTRS)

    Gaier, Todd C.; McGrath, William R.

    2010-01-01

    A safe, non-invasive method for forming images through clothing of large groups of people, in order to search for concealed weapons either made of metal or not, has been developed. A millimeter wavelength scanner designed in a unique, ring-shaped configuration can obtain a full 360 image of the body with a resolution of less than a millimeter in only a few seconds. Millimeter waves readily penetrate normal clothing, but are highly reflected by the human body and concealed objects. Millimeter wave signals are nonionizing and are harmless to human tissues when used at low power levels. The imager (see figure) consists of a thin base that supports a small-diameter vertical post about 7 ft (=2.13 m) tall. Attached to the post is a square-shaped ring 2 in. (=5 cm) wide and 3 ft (=91 cm) on a side. The ring is oriented horizontally, and is supported halfway along one side by a connection to a linear bearing on the vertical post. A planar RF circuit board is mounted to the inside of each side of the ring. Each circuit board contains an array of 30 receivers, one transmitter, and digitization electronics. Each array element has a printed-circuit patch antenna coupled to a pair of mixers by a 90 coupler. The mixers receive a reference local oscillator signal to a subharmonic of the transmitter frequency. A single local oscillator line feeds all 30 receivers on the board. The resulting MHz IF signals are amplified and carried to the edge of the board where they are demodulated and digitized. The transmitted signal is derived from the local oscillator at a frequency offset determined by a crystal oscillator. One antenna centrally located on each side of the square ring provides the source illumination power. The total transmitted power is less than 100 mW, resulting in an exposure level that is completely safe to humans. The output signals from all four circuit boards are fed via serial connection to a data processing computer. The computer processes the approximately 1-MB

  12. Feasibility study of in vivo partial body potassium determination in the human body using gamma-ray spectroscopy

    NASA Astrophysics Data System (ADS)

    Ramirez, Lisa Marie

    This work investigates partial body potassium determination in the human body using gamma-ray spectroscopy. Potassium is an essential element in the human body that controls many of the enzyme systems and intra- and extra-cellular water flow. Potassium is symptomatic to several disease cases and has gender and ethnic variability. This work assesses the feasibility to measure partial body potassium in three specific regions: brain, arm, and leg, that are of interest to multiple sclerosis, chronic renal failure, and spinal cord injury, respectively. Three detector systems were constructed and their capabilities assessed. System characterization and analytical procedure for potassium evaluation and determination are presented together with experimental and initial clinical results. The results indicate that partial body potassium measurement is viable, statistically reproducible, and has potential clinical significance.

  13. Computational Electromagnetic Dosimetry of a Human Body in a Vehicle for Plane-wave Exposure

    NASA Astrophysics Data System (ADS)

    Hirata, Akimasa

    The present study investigated whole-body specific absorption rate of a human body in a vehicle cabin for plane-wave exposure. The rationale for this investigation is that fields in the vehicle without human have been enhanced in particular frequency region due to standing waves, and thus power absorption in the human body is of interest. For our computational results, the whole-body average specific absorption rate of the human in the vehicle was found to be 60% smaller than that in free space. The reason for this upset is that the standing wave over the vehicle cabin was suppressed due to power absorption by the human.

  14. Central respiratory chemosensitivity and cerebrovascular CO2 reactivity: a rebreathing demonstration illustrating integrative human physiology.

    PubMed

    MacKay, Christina M; Skow, Rachel J; Tymko, Michael M; Boulet, Lindsey M; Davenport, Margie H; Steinback, Craig D; Ainslie, Philip N; Lemieux, Chantelle C M; Day, Trevor A

    2016-03-01

    One of the most effective ways of engaging students of physiology and medicine is through laboratory demonstrations and case studies that combine 1) the use of equipment, 2) problem solving, 3) visual representations, and 4) manipulation and interpretation of data. Depending on the measurements made and the type of test, laboratory demonstrations have the added benefit of being able to show multiple organ system integration. Many research techniques can also serve as effective demonstrations of integrative human physiology. The "Duffin" hyperoxic rebreathing test is often used in research settings as a test of central respiratory chemosensitivity and cerebrovascular reactivity to CO2. We aimed to demonstrate the utility of the hyperoxic rebreathing test for both respiratory and cerebrovascular responses to increases in CO2 and illustrate the integration of the respiratory and cerebrovascular systems. In the present article, methods such as spirometry, respiratory gas analysis, and transcranial Doppler ultrasound are described, and raw data traces can be adopted for discussion in a tutorial setting. If educators have these instruments available, instructions on how to carry out the test are provided so students can collect their own data. In either case, data analysis and quantification are discussed, including principles of linear regression, calculation of slope, the coefficient of determination (R(2)), and differences between plotting absolute versus normalized data. Using the hyperoxic rebreathing test as a demonstration of the complex interaction and integration between the respiratory and cerebrovascular systems provides senior undergraduate, graduate, and medical students with an advanced understanding of the integrative nature of human physiology. PMID:26873894

  15. Toward Scalable Trustworthy Computing Using the Human-Physiology-Immunity Metaphor

    SciTech Connect

    Hively, Lee M; Sheldon, Frederick T

    2011-01-01

    The cybersecurity landscape consists of an ad hoc patchwork of solutions. Optimal cybersecurity is difficult for various reasons: complexity, immense data and processing requirements, resource-agnostic cloud computing, practical time-space-energy constraints, inherent flaws in 'Maginot Line' defenses, and the growing number and sophistication of cyberattacks. This article defines the high-priority problems and examines the potential solution space. In that space, achieving scalable trustworthy computing and communications is possible through real-time knowledge-based decisions about cyber trust. This vision is based on the human-physiology-immunity metaphor and the human brain's ability to extract knowledge from data and information. The article outlines future steps toward scalable trustworthy systems requiring a long-term commitment to solve the well-known challenges.

  16. Xenobiotics shape the physiology and gene expression of the active human gut microbiome

    PubMed Central

    Maurice, Corinne Ferrier; Haiser, Henry Joseph; Turnbaugh, Peter James

    2012-01-01

    SUMMARY The human gut contains trillions of microorganisms that influence our health by metabolizing xenobiotics, including host-targeted drugs and antibiotics. Recent efforts have characterized the diversity of this host-associated community, but it remains unclear which microorganisms are active and what perturbations influence this activity. Here, we combine flow cytometry, 16S rRNA gene sequencing, and metatranscriptomics to demonstrate that the gut contains a distinctive set of active microorganisms, primarily Firmicutes. Short-term exposure to a panel of xenobiotics significantly affected the physiology, structure, and gene expression of this active gut microbiome. Xenobiotic-responsive genes were found across multiple bacterial phyla, encoding antibiotic resistance, drug metabolism, and stress response pathways. These results demonstrate the power of moving beyond surveys of microbial diversity to better understand metabolic activity, highlight the unintended consequences of xenobiotics, and suggest that attempts at personalized medicine should consider inter-individual variations in the active human gut microbiome. PMID:23332745

  17. Social relationships and physiological determinants of longevity across the human life span.

    PubMed

    Yang, Yang Claire; Boen, Courtney; Gerken, Karen; Li, Ting; Schorpp, Kristen; Harris, Kathleen Mullan

    2016-01-19

    Two decades of research indicate causal associations between social relationships and mortality, but important questions remain as to how social relationships affect health, when effects emerge, and how long they last. Drawing on data from four nationally representative longitudinal samples of the US population, we implemented an innovative life course design to assess the prospective association of both structural and functional dimensions of social relationships (social integration, social support, and social strain) with objectively measured biomarkers of physical health (C-reactive protein, systolic and diastolic blood pressure, waist circumference, and body mass index) within each life stage, including adolescence and young, middle, and late adulthood, and compare such associations across life stages. We found that a higher degree of social integration was associated with lower risk of physiological dysregulation in a dose-response manner in both early and later life. Conversely, lack of social connections was associated with vastly elevated risk in specific life stages. For example, social isolation increased the risk of inflammation by the same magnitude as physical inactivity in adolescence, and the effect of social isolation on hypertension exceeded that of clinical risk factors such as diabetes in old age. Analyses of multiple dimensions of social relationships within multiple samples across the life course produced consistent and robust associations with health. Physiological impacts of structural and functional dimensions of social relationships emerge uniquely in adolescence and midlife and persist into old age. PMID:26729882

  18. Social relationships and physiological determinants of longevity across the human life span

    PubMed Central

    Yang, Yang Claire; Boen, Courtney; Gerken, Karen; Li, Ting; Schorpp, Kristen; Harris, Kathleen Mullan

    2016-01-01

    Two decades of research indicate causal associations between social relationships and mortality, but important questions remain as to how social relationships affect health, when effects emerge, and how long they last. Drawing on data from four nationally representative longitudinal samples of the US population, we implemented an innovative life course design to assess the prospective association of both structural and functional dimensions of social relationships (social integration, social support, and social strain) with objectively measured biomarkers of physical health (C-reactive protein, systolic and diastolic blood pressure, waist circumference, and body mass index) within each life stage, including adolescence and young, middle, and late adulthood, and compare such associations across life stages. We found that a higher degree of social integration was associated with lower risk of physiological dysregulation in a dose–response manner in both early and later life. Conversely, lack of social connections was associated with vastly elevated risk in specific life stages. For example, social isolation increased the risk of inflammation by the same magnitude as physical inactivity in adolescence, and the effect of social isolation on hypertension exceeded that of clinical risk factors such as diabetes in old age. Analyses of multiple dimensions of social relationships within multiple samples across the life course produced consistent and robust associations with health. Physiological impacts of structural and functional dimensions of social relationships emerge uniquely in adolescence and midlife and persist into old age. PMID:26729882

  19. Human Peripheral Clocks: Applications for Studying Circadian Phenotypes in Physiology and Pathophysiology

    PubMed Central

    Saini, Camille; Brown, Steven A.; Dibner, Charna

    2015-01-01

    Most light-sensitive organisms on earth have acquired an internal system of circadian clocks allowing the anticipation of light or darkness. In humans, the circadian system governs nearly all aspects of physiology and behavior. Circadian phenotypes, including chronotype, vary dramatically among individuals and over individual lifespan. Recent studies have revealed that the characteristics of human skin fibroblast clocks correlate with donor chronotype. Given the complexity of circadian phenotype assessment in humans, the opportunity to study oscillator properties by using cultured primary cells has the potential to uncover molecular details difficult to assess directly in humans. Since altered properties of the circadian oscillator have been associated with many diseases including metabolic disorders and cancer, clock characteristics assessed in additional primary cell types using similar technologies might represent an important tool for exploring the connection between chronotype and disease, and for diagnostic purposes. Here, we review implications of this approach for gathering insights into human circadian rhythms and their function in health and disease. PMID:26029154

  20. Possible psycho-physiological consequences of human long-term space missions

    NASA Astrophysics Data System (ADS)

    Belisheva, N. K.; Lammer, H.; Biernat, H. K.; Kachanova, T. L.; Kalashnikova, I. V.

    Experiments carried out on the Earth s surface during different years and under contrast periods of solar activity have shown that the functional state of biosystems including the human organisms are controlled by global and local geocosmical agents Our finding have a close relation to space research because they demonstrate the reactions of biosystems on variations of global and local geocosmical agents and the mechanisms of modulations of biosystems state by geocosmical agents We revealed the role of variations of the geomagnetic field for the stimulation of immune systems functional state of peripheral blood human brain growth of microflora skin covers and pathogenic microorganisms The study of the psycho-physiological state of the human organism has demonstrated that an increase of the neutron intensity near the Earth s surface is associated with anxiety decrease of normal and increase of paradox reactions of examinees The analysis of the human brain functional state in dependent on the geomagnetic variation structure dose under exposure to the variations of geomagnetic field in a certain amplitude-frequency range and also the intensity of the nucleon component of secondary cosmic rays showed that the stable and unstable states of the human brain are determined by geomagnetic field variations and the intensity of the nucleon component The stable state of the brain manifested under the periodic oscillations of the geomagnetic field in a certain amplitude-frequency range The low level of geomagnetic activity associated with an

  1. A physiologically-based pharmacokinetic (PBPK) model of squalene-containing adjuvant in human vaccines.

    PubMed

    Tegenge, Million A; Mitkus, Robert J

    2013-10-01

    Squalene is used in the oil phase of certain emulsion vaccine adjuvants, but its fate as a vaccine component following intramuscular (IM) injection in humans is unknown. In this study, we constructed a physiologically-based pharmacokinetic (PBPK) model for intramuscularly injected squalene-in-water (SQ/W) emulsion, in order to make a quantitative estimation of the tissue distribution of squalene following a single IM injection in humans. The PBPK model incorporates relevant physicochemical properties of squalene; estimates of the time course of cracking of a SQ/W emulsion; anatomical and physiological parameters at the injection site and beyond; and local, preferential lymphatic transport. The model predicts that a single dose of SQ/W emulsion will be removed from human deltoid muscle within six days following IM injection. The major proportion of the injected squalene will be distributed to draining lymph nodes and adipose tissues. The model indicates slow decay from the latter compartment most likely due to partitioning into neutral lipids and a low rate of squalene biotransformation there. Parallel pharmacokinetic modeling for mouse muscle suggests that the kinetics of SQ/W emulsion correspond to the immunodynamic time course of a commercial squalene-containing adjuvant reported in that species. In conclusion, this study makes important pharmacokinetic predictions of the fate of a squalene-containing emulsion in humans. The results of this study may be relevant for understanding the immunodynamics of this new class of vaccine adjuvants and may be useful in future quantitative risk analyses that incorporate mode-of-action data. PMID:23912214

  2. Human Spirometry: Computerized Data Acquisition in the Undergraduate Human Physiology Laboratory.

    ERIC Educational Resources Information Center

    Braun, Bradley T.; Mulstay, Richard E.

    1993-01-01

    Applies microcomputer technology to the development of a data acquisition and analysis system for the study of measuring the human lung capacity and metabolism. Discusses the chain-compensated spirometer, interfacing hardware, data acquisition hardware and software, and the applicability of the system to other biological measurements. (MDH)

  3. Lower Body Negative Pressure Treadmill Exercise and Resistive Exercise Countermeasures Maintain Physiologic Function in Women during Simulated Microgravity

    NASA Technical Reports Server (NTRS)

    Macias, B. R.; Schneider, S. M.; Lee, S. M. C.; Guinet, P.; Hughson, R. L.; Smith, Scott M.; Watenpaugh, D. E.; Hargens, A. R.

    2008-01-01

    We hypothesized that supine LBNP treadmill exercise combined with Flywheel resistive exercise maintains upright physiologic responses following 60-days of head-down tilt (HDT) bed rest (BR). METHODS: 16 healthy women (age 25-40 years) underwent 60-days HDT (-6deg.) BR. Women were assigned to either a non-exercise control group (CON, n=8) or to an exercise group (EX, n=8). EX subjects performed a 40-min, variable intensity LBNP exercise protocol at foot-ward forces between 1.0-1.1 times body weight, followed by 10- min of resting LBNP 3-4 days/week. Resistive exercise of maximal concentric and eccentric supine leg press and heel raise exercises were performed using a flywheel ergometer 2-3 days/week. IRBs approved this study with informed/written consent. RESULTS: Post-BR VO2pk was not different in EX (-3.3+/-1.2%) but decreased significantly in CON (-21.2+/-2.1%), p< 0.05. Post-BR orthostatic tolerance time (mean se) decreased significantly less in EX (19.3+/-1.3 to 14.4+/-1.5 min) than in CON (17.5+/-0.1 to 9.1+/- 1.5 min), p=0.03. Post-BR muscle strength decreased significantly in CON, but was preserved in EX. Post-BR bone resorption was greater than pre-BR in both groups (p<0.05). Bone formation markers, were significantly elevated (p<0.05) in EX than in CON. CONCLUSIONS: Supine LBNP treadmill exercise along with flywheel resistive exercise maintains upright exercise capacity, orthostatic responses and muscle strength during 60-days HDT BR.

  4. Preliminary results of Physiological plant growth modelling for human life support in space

    NASA Astrophysics Data System (ADS)

    Sasidharan L, Swathy; Dussap, Claude-Gilles; Hezard, Pauline

    2012-07-01

    Human life support is fundamental and crucial in any kind of space explorations. MELiSSA project of European Space Agency aims at developing a closed, artificial ecological life support system involving human, plants and micro organisms. Consuming carbon dioxide and water from the life support system, plants grow in one of the chambers and convert it into food and oxygen along with potable water. The environmental conditions, nutrient availability and its consumption of plants should be studied and necessarily modeled to predict the amount of food, oxygen and water with respect to the environmental changes and limitations. The reliability of a completely closed system mainly depends on the control laws and strategies used. An efficient control can occur, only if the system to control is itself well known, described and ideally if the responses of the system to environmental changes are predictable. In this aspect, the general structure of plant growth model has been designed together with physiological modelling.The physiological model consists of metabolic models of leaves, stem and roots, of which concern specific metabolisms of the associated plant parts. On the basis of the carbon source transport (eg. sucrose) through stem, the metabolic models (leaf and root) can be interconnected to each other and finally coupled to obtain the entire plant model. For the first step, leaf metabolic model network was built using stoichiometric, mass and energy balanced metabolic equations under steady state approach considering all necessary plant pathways for growth and maintenance of leaves. As the experimental data for lettuce plants grown in closed and controlled environmental chambers were available, the leaf metabolic model has been established for lettuce leaves. The constructed metabolic network is analyzed using known stoichiometric metabolic technique called metabolic flux analysis (MFA). Though, the leaf metabolic model alone is not sufficient to achieve the

  5. Mathematical modeling of the human body during water replacement and dehydration: body water changes.

    PubMed

    Downey, D; Seagrave, R C

    2000-03-01

    A model of the human body that integrates the variables involved in temperature regulation and blood gas transport within the cardiovascular and respiratory systems is presented here. It expands upon previous work to describe the competition between skin and muscles when both require increased blood flows during exercise and/or heat stress. First, a detailed study of the control relations used to predict skin blood flow was undertaken. Four other control relations employed in the model were also examined and modified as indicated by empirical results found in literature. Internal responses to exercise and/or heat stress can affect both thermoregulation and the cardiorespiratory system. Dehydration was studied in addition to complete water replacement during similar environmental and exercise situations. Control relations for skin blood flow and evaporative heat loss were modified and a water balance was added to study how the loss of water through sweat can be limiting. Runoff from sweating as a function of relative humidity was introduced along with evaporation, and these results were compared to data to validate the model. PMID:10784092

  6. Physiologically Based Pharmacokinetic modeling of the temperature-dependent dermal absorption of chloroform by humans following bath water exposures

    SciTech Connect

    Corley, Rick A. ); Gordon, Syd M.; Wallace, Lance A.

    2000-01-14

    The kinetics of chloroform in the exhaled breath of human volunteers exposed skin-only via bath water (concentrations < 100 ppb) were analyzed using a physiologically based pharmacokinetic (PBPK) model. Significant increases in exhaled chloroform (and thus bioavailability) were observed as exposure temperatures were increased from 30 to 40?C. The blood flows to the skin and effective skin permeability coefficients (Kp) were both varied to reflect the temperature-dependent changes in physiology and exhalation kinetics. At 40?C, no differences were observed between males and females. Therefore, Kp?s were determined ({approx}0.06 cm/hr) at a skin blood flow rate of 18% of the cardiac output. At 30 and 35?C, males exhaled more chloroform than females resulting in lower effective Kp?s calculated for females. At these lower temperatures, the blood flow to the skin was also reduced. Total amounts of chloroform absorbed averaged 41.9 and 43.6 mg for males and 11.5 and 39.9 mg for females exposed at 35 and 40?C, respectively. At 30?C, only 2/5 males and 1/5 females had detectable concentrations of chloroform in their exhaled breath. For perspective, the total intake of chloroform would have ranged from 79 - 194 mg if the volunteers had consumed 2 L of water orally at the concentrations used in this study. Thus, the relative contribution of dermal uptake of chloroform to the total body burdens associated with bathing for 30 min and drinking 2 L of water (ignoring contributions from inhalation exposures) was predicted to range from 1-28% depending on the temperature of the bath.

  7. Body futures: the case against marketing human organs.

    PubMed

    Dougherty, C J

    1987-06-01

    Creation of a market for the buying and selling of human organs for transplantation, even if it did allow supply to match demand, would be a serious mistake. Even if the market were fairly constructed, it might not dramatically increase the supply of transplantable organs, since donations likely would decrease if selling were allowed. Such a market would create a relative disadvantage for the poor, who would feel disproportionately greater pressure to sell their organs than would the wealthy. The possibility of realizing a profit from the organs of the dead could provide an incentive for murder or for doing less than we might to save lives. An organ market, where parts of a person are viewed as commodities, could lead to a general cheapening and coarsening of human relationships. Any organ selling system would create an economic relationship between buyer and seller, rather than a charitable one, raising quality control problems. The economic system, would drive out the volunteer donor system, sapping the altruistic bond that draws people together. Finally, an organ market presents a metaphysical threat in that it demeans our bodies to the status of articles to trade. An alternative to the current voluntary donor system and an organ market is to presume passive consent to organ donation with the right to informed refusal. Unless a record of the decedent's opposition to organ removal exists, the next of kin objects on being informed of the intent to remove organs, or the decedent was a member of a group known to oppose organ removal, we should presume a person's willingness to donate organs after death to save another person's life. PMID:10282295

  8. [Measurement of human body fat by means of gravimetry. Application of Archimedes' principle].

    PubMed

    Dettwiler, W; Ribordy, M; Donath, A; Scherrer, J R

    1978-12-01

    The weighing of the human body under water is an application of Archimedes' law. Fat being lighter than water or than the structures of lean body mass, body fat can be measured by determining the specific gravity of the human body; that is, by underwater weighing. Body fat has been determined in an "ideal" sample of 14 men and 23 women, all aged 20 years. Testing against a reference measure of body fat makes it possible to test the validity of some anthropometric measurements and of some indices of obesity. These indices offer no advantages over anthropometric measurements. PMID:715434

  9. Screening of chemicals for human bioaccumulative potential with a physiologically based toxicokinetic model.

    PubMed

    Tonnelier, Arnaud; Coecke, Sandra; Zaldívar, José-Manuel

    2012-03-01

    Human bioaccumulative potential is an important element in the risk assessment of chemicals. Due to the high number of synthetic chemicals, there exists the need to develop prioritisation strategies. The purpose of this study was to develop a predictive tool for human bioaccumulation risk assessment that incorporates not only the chemical properties of the compounds, but also the processes that tend to decrease the concentration of the compound such as metabolisation. We used a generic physiologically based toxicokinetic model that based on in vitro human liver metabolism data, minimal renal excretion and a constant exposure was able to assess the bioaccumulative potential of a chemical. The approach has been analysed using literature data on well-known bioaccumulative compounds and liver metabolism data from the ECVAM database and a subset of the ToxCast phase I chemical library-in total 94 compounds covering pharmaceuticals, plant protection products and industrial chemicals. Our results provide further evidence that partitioning properties do not allow for a reliable screening criteria for human chemical hazard. Our model, based on a 100% intestinal absorption assumption, suggests that metabolic clearance, plasma protein-binding properties and renal excretion are the main factors in determining whether bioaccumulation will occur and its amount. It is essential that in vitro metabolic clearance tests with metabolic competent cell lines as well as plasma protein-binding assays be performed for suspected bioaccumulative compounds. PMID:22089525

  10. Elaboration of a new culture medium for physiological studies on human sperm motility and capacitation.

    PubMed

    Mortimer, D

    1986-06-01

    The formulation of a new medium based upon published data on human tubal fluid and blood plasma is described. Sperm motility was well maintained for periods of up to 6 h in this 'synthetic tubal fluid' (STF), and movement characteristics (velocity of progression and amplitude of lateral head displacement) were quantitatively and qualitatively similar to values previously reported for other complex media. STF also supported human sperm capacitation and the spontaneous acrosome reaction as determined using the zona-free hamster egg penetration test. Spermatozoa pre-incubated in STF containing blood plasma levels of taurine (86 microM) for 3 h penetrated significantly more oocytes than parallel sperm populations pre-incubate in STF lacking taurine (P less than 0.001). This difference was no longer significant after 5 h of pre-incubation. These findings indicate a possible role for taurine in human sperm capacitation, and demonstrate the potential value of STF for performing more physiological invitro studies on human sperm function. PMID:3558765

  11. MicroRNAs: Control and Loss of Control in Human Physiology and Disease

    PubMed Central

    Li, Min; Marin-Muller, Christian; Bharadwaj, Uddalak; Chow, Kwong-Hon; Yao, Qizhi; Chen, Changyi

    2010-01-01

    Analysis of the human genome indicated that a large fraction of the genome sequences are RNAs that do not encode any proteins, also known as non-coding RNAs. MicroRNAs (miRNAs) are a group of small non-coding RNA molecules, with 20–22-nucleotide (nt) in length, and are predicted to control the activity of approximately 30% of all protein-coding genes in mammals. miRNAs play important roles in many diseases including cancer, cardiovascular disease, and immune disorders. The expression of miRNAs can be regulated by epigenetic modification, DNA copy number change, and genetic mutations. miRNAs can serve as a valuable therapeutic target for a large number of diseases. For miRNAs with oncogenic capabilities, potential therapies include miRNA silencing, antisense blocking, and miRNA modifications. For miRNAs with tumor suppression functions, over-expression of those miRNAs might be a useful strategy to inhibit tumor growth. In this review, we discuss the current progress of miRNA research, regulation of miRNA expression, prediction of miRNA targets, and regulatory role of miRNAs in human physiology and diseases, with a specific focus on miRNAs in pancreatic cancer, liver cancer, colon rectal cancer, cardiovascular disease, immune system, and infectious disease. This review provides valuable information for clinicians and researchers who want to recognize the newest advances in this new field and identify possible lines of investigation in miRNAs as important mediators in human physiology and diseases. PMID:19030926

  12. Physiological Evidence for a Midline Spatial Channel in Human Auditory Cortex.

    PubMed

    Briley, Paul M; Goman, Adele M; Summerfield, A Quentin

    2016-08-01

    Studies with humans and other mammals have provided support for a two-channel representation of horizontal ("azimuthal") space in the auditory system. In this representation, location-sensitive neurons contribute activity to one of two broadly tuned channels whose responses are compared to derive an estimate of sound-source location. One channel is maximally responsive to sounds towards the left and the other to sounds towards the right. However, recent psychophysical studies of humans, and physiological studies of other mammals, point to the presence of an additional channel, maximally responsive to the midline. In this study, we used electroencephalography to seek physiological evidence for such a midline channel in humans. We measured neural responses to probe stimuli presented from straight ahead (0 °) or towards the right (+30 ° or +90 °). Probes were preceded by adapter stimuli to temporarily suppress channel activity. Adapters came from 0 ° or alternated between left and right (-30 ° and +30 ° or -90 ° and +90 °). For the +90 ° probe, to which the right-tuned channel would respond most strongly, both accounts predict greatest adaptation when the adapters are at ±90 °. For the 0 ° probe, the two-channel account predicts greatest adaptation from the ±90 ° adapters, while the three-channel account predicts greatest adaptation when the adapters are at 0 ° because these adapters stimulate the midline-tuned channel which responds most strongly to the 0 ° probe. The results were consistent with the three-channel account. In addition, a computational implementation of the three-channel account fitted the probe response sizes well, explaining 93 % of the variance about the mean, whereas a two-channel implementation produced a poor fit and explained only 61 % of the variance. PMID:27164943

  13. The use of computers to teach human anatomy and physiology to allied health and nursing students

    NASA Astrophysics Data System (ADS)

    Bergeron, Valerie J.

    Educational institutions are under tremendous pressure to adopt the newest technologies in order to prepare their students to meet the challenges of the twenty-first century. For the last twenty years huge amounts of money have been spent on computers, printers, software, multimedia projection equipment, and so forth. A reasonable question is, "Has it worked?" Has this infusion of resources, financial as well as human, resulted in improved learning? Are the students meeting the intended learning goals? Any attempt to develop answers to these questions should include examining the intended goals and exploring the effects of the changes on students and faculty. This project investigated the impact of a specific application of a computer program in a community college setting on students' attitudes and understanding of human anatomy and physiology. In this investigation two sites of the same community college with seemingly similar students populations, seven miles apart, used different laboratory activities to teach human anatomy and physiology. At one site nursing students were taught using traditional dissections and laboratory activities; at the other site two of the dissections, specifically cat and sheep pluck, were replaced with the A.D.A.M.RTM (Animated Dissection of Anatomy for Medicine) computer program. Analysis of the attitude data indicated that students at both sites were extremely positive about their laboratory experiences. Analysis of the content data indicated a statistically significant difference in performance between the two sites in two of the eight content areas that were studied. For both topics the students using the computer program scored higher. A detailed analysis of the surveys, interviews with faculty and students, examination of laboratory materials, and observations of laboratory facilities in both sites, and cost-benefit analysis led to the development of seven recommendations. The recommendations call for action at the level of the

  14. [Morphometric evaluation of relative adipose tissue content in the human body].

    PubMed

    Sheikh-Zade, Yu R

    2012-01-01

    Analysis of the mathematical models of the human body composition revealed main shortcomings of body mass index (A. Quetelet, 1832). This allowed to offer more accurate body mass index (BMI = M/H3), body build index [BBI = (BMI)1/2] and body fatness index (BFI = M/HC2), where (M), (H) and (C) signified the mass, height and wrist circumference correspondingly. PMID:23659047

  15. Target recognition in passive terahertz image of human body

    NASA Astrophysics Data System (ADS)

    Zhao, Ran; Zhao, Yuan-meng; Deng, Chao; Zhang, Cun-lin; Li, Yue

    2014-11-01

    THz radiation can penetrate through many nonpolar dielectric materials and can be used for nondestructive/noninvasive sensing and imaging of targets under nonpolar, nonmetallic covers or containers. Thus using THz systems to "see through" concealing barriers (i.e. packaging, corrugated cardboard, clothing) has been proposed as a new security screening method. Objects that can be detected by THz include concealed weapons, explosives, and chemical agents under clothing. Passive THz imaging system can detect THz wave from human body without transmit any electromagnetic wave, and the suspicious objects will become visible because the THz wave is blocked by this items. We can find out whether or not someone is carrying dangerous objects through this image. In this paper, the THz image enhancement, segmentation and contour extraction algorithms were studied to achieve effective target image detection. First, the terahertz images are enhanced and their grayscales are stretched. Then we apply global threshold segmentation to extract the target, and finally the targets are marked on the image. Experimental results showed that the algorithm proposed in this paper can extract and mark targets effectively, so that people can identify suspicious objects under clothing quickly. The algorithm can significantly improve the usefulness of the terahertz security apparatus.

  16. The Influence of Human Body Orientation on Distance Judgments

    PubMed Central

    Jung, Edgard; Takahashi, Kohske; Watanabe, Katsumi; de la Rosa, Stephan; Butz, Martin V.; Bülthoff, Heinrich H.; Meilinger, Tobias

    2016-01-01

    People maintain larger distances to other peoples’ front than to their back. We investigated if humans also judge another person as closer when viewing their front than their back. Participants watched animated virtual characters (avatars) and moved a virtual plane toward their location after the avatar was removed. In Experiment 1, participants judged avatars, which were facing them as closer and made quicker estimates than to avatars looking away. In Experiment 2, avatars were rotated in 30 degree steps around the vertical axis. Observers judged avatars roughly facing them (i.e., looking max. 60 degrees away) as closer than avatars roughly looking away. No particular effect was observed for avatars directly facing and also gazing at the observer. We conclude that body orientation was sufficient to generate the asymmetry. Sensitivity of the orientation effect to gaze and to interpersonal distance would have suggested involvement of social processing, but this was not observed. We discuss social and lower-level processing as potential reasons for the effect. PMID:27014108

  17. Constraint, natural selection, and the evolution of human body form.

    PubMed

    Savell, Kristen R R; Auerbach, Benjamin M; Roseman, Charles C

    2016-08-23

    Variation in body form among human groups is structured by a blend of natural selection driven by local climatic conditions and random genetic drift. However, attempts to test ecogeographic hypotheses have not distinguished between adaptive traits (i.e., those that evolved as a result of selection) and those that evolved as a correlated response to selection on other traits (i.e., nonadaptive traits), complicating our understanding of the relationship between climate and morphological distinctions among populations. Here, we use evolutionary quantitative methods to test if traits previously identified as supporting ecogeographic hypotheses were actually adaptive by estimating the force of selection on individual traits needed to drive among-group differentiation. Our results show that not all associations between trait means and latitude were caused by selection acting directly on each individual trait. Although radial and tibial length and biiliac and femoral head breadth show signs of responses to directional selection matching ecogeographic hypotheses, the femur was subject to little or no directional selection despite having shorter values by latitude. Additionally, in contradiction to ecogeographic hypotheses, the humerus was under directional selection for longer values by latitude. Responses to directional selection in the tibia and radius induced a nonadaptive correlated response in the humerus that overwhelmed its own trait-specific response to selection. This result emphasizes that mean differences between groups are not good indicators of which traits are adaptations in the absence of information about covariation among characteristics. PMID:27482101

  18. Wearable thermoelectric generator for harvesting human body heat energy

    NASA Astrophysics Data System (ADS)

    Kim, Min-Ki; Kim, Myoung-Soo; Lee, Seok; Kim, Chulki; Kim, Yong-Jun

    2014-10-01

    This paper presents the realization of a wearable thermoelectric generator (TEG) in fabric for use in clothing. A TEG was fabricated by dispenser printing of Bi0.5Sb1.5Te3 and Bi2Se0.3Te2.7 in a polymer-based fabric. The prototype consisted of 12 thermocouples connected by conductive thread over an area of 6 × 25 mm2. The device generated a power of 224 nW for a temperature difference of 15 K. When the TEG was used on the human body, the measured output power was 224 nW in an ambient temperature of 5 °C. The power of the TEG was affected by the movement of the wearer. A higher voltage was maintained while walking than in a stationary state. In addition, the device did not deform after it was bent and stretched several times. The prospect of using the TEG in clothing applications was confirmed under realistic conditions.

  19. Molecular Crowding Favors Reactivity of a Human Ribozyme Under Physiological Ionic Conditions

    PubMed Central

    Strulson, Christopher A.; Yennawar, Neela H.; Rambo, Robert P.; Bevilacqua, Philip C.

    2013-01-01

    In an effort to relate RNA folding to function under cellular-like conditions, we monitored the self-cleavage reaction of the human hepatitis delta virus (HDV)-like CPEB3 ribozyme in the background of physiological ionic concentrations and various crowding and cosolute agents. We found that under physiological free Mg2+ concentrations (~0.1 to 0.5 mM Mg2+), both crowders and cosolutes stimulate the rate of self-cleavage, up to ~6-fold, but that in 10 mM Mg2+—conditions widely used for in vitro ribozyme studies—these same additives have virtually no effect on self-cleavage rate. We further observe a dependence of self-cleavage rate on crowder size, wherein rate stimulation is diminished for crowders larger than the size of the unfolded RNA. Monitoring effects of crowding and cosolute agents on rates in biological amounts of urea revealed additive-promoted increases in both low and high Mg2+ concentrations, with a maximal stimulation of more than 10-fold and a rescue of the rate to its urea-free values. Small-angle X-ray scattering (SAXS) experiments reveal a structural basis for this stimulation in that higher molecular weight crowding agents favor a more compact form of the ribozyme in 0.5 mM Mg2+ that is essentially equivalent to the form under standard ribozyme conditions of 10 mM Mg2+ and no crowder. This finding suggests that at least a portion of the rate enhancement arises from favoring the native RNA tertiary structure. We conclude that cellular-like crowding supports ribozyme reactivity by favoring a compact form of the ribozyme, but only under physiological ionic and cosolute conditions. PMID:24187989

  20. Earthing (Grounding) the Human Body Reduces Blood Viscosity—a Major Factor in Cardiovascular Disease

    PubMed Central

    Chevalier, Gaétan; Sinatra, Stephen T.; Delany, Richard M.

    2013-01-01

    Abstract Objectives Emerging research is revealing that direct physical contact of the human body with the surface of the earth (grounding or earthing) has intriguing effects on human physiology and health, including beneficial effects on various cardiovascular risk factors. This study examined effects of 2 hours of grounding on the electrical charge (zeta potential) on red blood cells (RBCs) and the effects on the extent of RBC clumping. Design/interventions Subjects were grounded with conductive patches on the soles of their feet and palms of their hands. Wires connected the patches to a stainless-steel rod inserted in the earth outdoors. Small fingertip pinprick blood samples were placed on microscope slides and an electric field was applied to them. Electrophoretic mobility of the RBCs was determined by measuring terminal velocities of the cells in video recordings taken through a microscope. RBC aggregation was measured by counting the numbers of clustered cells in each sample. Settings/location Each subject sat in a comfortable reclining chair in a soundproof experiment room with the lights dimmed or off. Subjects Ten (10) healthy adult subjects were recruited by word-of-mouth. Results Earthing or grounding increased zeta potentials in all samples by an average of 2.70 and significantly reduced RBC aggregation. Conclusions Grounding increases the surface charge on RBCs and thereby reduces blood viscosity and clumping. Grounding appears to be one of the simplest and yet most profound interventions for helping reduce cardiovascular risk and cardiovascular events. PMID:22757749

  1. Erythropoietin enhances whole body lipid oxidation during prolonged exercise in humans.

    PubMed

    Caillaud, Corinne; Connes, Philippe; Ben Saad, Helmi; Mercier, Jacques

    2015-03-01

    Animal studies have suggested that erythropoietin, besides its well-known hematopoietic effects, can modulate metabolism and prevent fat accumulation. We investigated the effects of repeated injections of recombinant human erythropoietin (EPO) on the balance of substrate oxidation during aerobic exercise in humans. Twelve healthy aerobically trained males received subcutaneously either moderate dose of EPO (50 U/kg, EPO) or saline injections (NaCl 0.9 %, control) three times a week for 4 weeks. Body weight, % fat, maximal aerobic capacity, and substrate utilization during exercise were assessed before and after treatment, while hemoglobin and hematocrit were monitored regularly during the treatment. Carbohydrate and fat oxidation were evaluated via indirect calorimetry, during a submaximal exercise performed at 75 % of the participants' maximal aerobic capacity (V̇(O2max)) for 60 min. Results showed that 4 weeks of EPO treatment significantly enhanced fat oxidation (+56 % in EPO versus -9 % in control) during exercise, independent of its effects on hematological parameters or V̇(O2max). This study shows that EPO can modulate substrate utilization during exercise, leading to enhanced fat utilization and lower use of carbohydrates. This opens new research directions exploring whether systemic EPO levels, in physiological conditions, participate to the modulation of fat oxidation. PMID:25567744

  2. Physiological evidence consistent with reduced neuroplasticity in human adolescents born preterm.

    PubMed

    Pitcher, Julia B; Riley, Alysha M; Doeltgen, Sebastian H; Kurylowicz, Lisa; Rothwell, John C; McAllister, Suzanne M; Smith, Ashleigh E; Clow, Angela; Kennaway, David J; Ridding, Michael C

    2012-11-14

    Preterm-born children commonly experience motor, cognitive, and learning difficulties that may be accompanied by altered brain microstructure, connectivity, and neurochemistry. However, the mechanisms linking the altered neurophysiology with the behavioral outcomes are unknown. Here we provide the first physiological evidence that human adolescents born preterm at or before 37 weeks of completed gestation have a significantly reduced capacity for cortical neuroplasticity, the key overall mechanism underlying learning and memory. We examined motor cortex neuroplasticity in three groups of adolescents who were born after gestations of ≤32 completed weeks (early preterm), 33-37 weeks (late preterm), and 38-41 weeks (term) using a noninvasive transcranial magnetic brain stimulation technique to induce long-term depression (LTD)-like neuroplasticity. Compared with term-born adolescents, both early and late preterm adolescents had reduced LTD-like neuroplasticity in response to brain stimulation that was also associated with low salivary cortisol levels. We also compared neuroplasticity in term-born adolescents with that in term-born young adults, finding that the motor cortex retains a relatively enhanced neuroplastic capacity in adolescence. These findings provide a possible mechanistic link between the altered brain physiology of preterm birth and the subsequent associated behavioral deficits, particularly in learning and memory. They also suggest that altered hypothalamic-pituitary-adrenal axis function due to preterm birth may be a significant modulator of this altered neuroplasticity. This latter finding may offer options in the development of possible therapeutic interventions. PMID:23152623

  3. A human body model for efficient numerical characterization of UWB signal propagation in wireless body area networks.

    PubMed

    Lim, Hooi Been; Baumann, Dirk; Li, Er-Ping

    2011-03-01

    Wireless body area network (WBAN) is a new enabling system with promising applications in areas such as remote health monitoring and interpersonal communication. Reliable and optimum design of a WBAN system relies on a good understanding and in-depth studies of the wave propagation around a human body. However, the human body is a very complex structure and is computationally demanding to model. This paper aims to investigate the effects of the numerical model's structure complexity and feature details on the simulation results. Depending on the application, a simplified numerical model that meets desired simulation accuracy can be employed for efficient simulations. Measurements of ultra wideband (UWB) signal propagation along a human arm are performed and compared to the simulation results obtained with numerical arm models of different complexity levels. The influence of the arm shape and size, as well as tissue composition and complexity is investigated. PMID:21062677

  4. The effect of physiological conditions on the surface structure of proteins: Setting the scene for human digestion of emulsions

    NASA Astrophysics Data System (ADS)

    Maldonado-Valderrama, J.; Gunning, A. P.; Ridout, M. J.; Wilde, P. J.; Morris, V. J.

    2009-10-01

    Understanding and manipulating the interfacial mechanisms that control human digestion of food emulsions is a crucial step towards improved control of dietary intake. This article reports initial studies on the effects of the physiological conditions within the stomach on the properties of the film formed by the milk protein ( β -lactoglobulin) at the air-water interface. Atomic force microscopy (AFM), surface tension and surface rheology techniques were used to visualize and examine the effect of gastric conditions on the network structure. The effects of changes in temperature, pH and ionic strength on a pre-formed interfacial structure were characterized in order to simulate the actual digestion process. Changes in ionic strength had little effect on the surface properties. In isolation, acidification reduced both the dilatational and the surface shear modulus, mainly due to strong repulsive electrostatic interactions within the surface layer and raising the temperature to body temperature accelerated the rearrangements within the surface layer, resulting in a decrease of the dilatational response and an increase of surface pressure. Together pH and temperature display an unexpected synergism, independent of the ionic strength. Thus, exposure of a pre-formed interfacial β -lactoglobulin film to simulated gastric conditions reduced the surface dilatational modulus and surface shear moduli. This is attributed to a weakening of the surface network in which the surface rearrangements of the protein prior to exposure to gastric conditions might play a crucial role.

  5. Comparative genomics using teleost fish helps to systematically identify target gene bodies of functionally defined human enhancers

    PubMed Central

    2013-01-01

    Background Human genome is enriched with thousands of conserved non-coding elements (CNEs). Recently, a medium throughput strategy was employed to analyze the ability of human CNEs to drive tissue specific expression during mouse embryogenesis. These data led to the establishment of publicly available genome wide catalog of functionally defined human enhancers. Scattering of enhancers over larger regions in vertebrate genomes seriously impede attempts to pinpoint their precise target genes. Such associations are prerequisite to explore the significance of this in vivo characterized catalog of human enhancers in development, disease and evolution. Results This study is an attempt to systematically identify the target gene-bodies for functionally defined human CNE-enhancers. For the purpose we adopted the orthology/paralogy mapping approach and compared the CNE induced reporter expression with reported endogenous expression pattern of neighboring genes. This procedure pinpointed specific target gene-bodies for the total of 192 human CNE-enhancers. This enables us to gauge the maximum genomic search space for enhancer hunting: 4 Mb of genomic sequence around the gene of interest (2 Mb on either side). Furthermore, we used human-rodent comparison for a set of 159 orthologous enhancer pairs to infer that the central nervous system (CNS) specific gene expression is closely associated with the cooperative interaction among at least eight distinct transcription factors: SOX5, HFH, SOX17, HNF3β, c-FOS, Tal1beta-E47S, MEF and FREAC. Conclusions In conclusion, the systematic wiring of cis-acting sites and their target gene bodies is an important step to unravel the role of in vivo characterized catalog of human enhancers in development, physiology and medicine. PMID:23432897

  6. Relationship Between Human Physiological Parameters And Geomagnetic Variations Of Solar Origin

    NASA Astrophysics Data System (ADS)

    Dimitrova, S.

    This study attempts to assess the influence of increased geomagnetic activity on some human physiological parameters. The blood pressure, heart rate and general well-being of 86 volunteers were measured (the latter by means of a standardized questionnaire) on work days in autumn 2001 (01/10 to 09/11) and in spring 2002 (08/04 to 28/05). These periods were chosen because of maximal expected geomagnetic activity. Altogether, 2799 recordings were obtained and analysed. MANOVA was employed to check the significance of the influence of three factors on the physiological parameters under consideration. The three factors were the following: 1) planetary geomagnetic activity level estimated by Ap-index and divided into five levels; 2) gender - males and females; 3) blood pressure degree - persons in the group examined were divided into hypotensive, normotensive and hypertensive. Post hoc analysis was performed to elicit the significance of differences in the factors' levels. The average arterial blood pressure of the group was found to increase significantly with the increase of geomagnetic activity level. The average increment of systolic and diastolic blood pressure reached 9%, which deserves attention from a medical point of view. This effect was present irrespectively of gender. Results obtained suppose that hypertensive persons have the highest sensitivity and the hypotensive persons have the lowest sensitivity of the arterial blood pressure to increase of geomagnetic activity. The results did not show significant changes in the heart rate. The percentage of the persons who reported subjective psycho-physiological complaints was also found to increase significantly with the geomagnetic activity increase. During severe geomagnetic storms 30% of the persons examined reported subjective complaints and the highest sensitivity was revealed for the hypertensive females. The results obtained add further evidence that blood pressure seems to be affected by geomagnetic

  7. Audited credential delegation: a usable security solution for the virtual physiological human toolkit.

    PubMed

    Haidar, Ali N; Zasada, Stefan J; Coveney, Peter V; Abdallah, Ali E; Beckles, Bruce; Jones, Mike A S

    2011-06-01

    We present applications of audited credential delegation (ACD), a usable security solution for authentication, authorization and auditing in distributed virtual physiological human (VPH) project environments that removes the use of digital certificates from end-users' experience. Current security solutions are based on public key infrastructure (PKI). While PKI offers strong security for VPH projects, it suffers from serious usability shortcomings in terms of end-user acquisition and management of credentials which deter scientists from exploiting distributed VPH environments. By contrast, ACD supports the use of local credentials. Currently, a local ACD username-password combination can be used to access grid-based resources while Shibboleth support is underway. Moreover, ACD provides seamless and secure access to shared patient data, tools and infrastructure, thus supporting the provision of personalized medicine for patients, scientists and clinicians participating in e-health projects from a local to the widest international scale. PMID:22670214

  8. Using Noninvasive Wearable Computers to Recognize Human Emotions from Physiological Signals

    NASA Astrophysics Data System (ADS)

    Lisetti, Christine Lætitia; Nasoz, Fatma

    2004-12-01

    We discuss the strong relationship between affect and cognition and the importance of emotions in multimodal human computer interaction (HCI) and user modeling. We introduce the overall paradigm for our multimodal system that aims at recognizing its users' emotions and at responding to them accordingly depending upon the current context or application. We then describe the design of the emotion elicitation experiment we conducted by collecting, via wearable computers, physiological signals from the autonomic nervous system (galvanic skin response, heart rate, temperature) and mapping them to certain emotions (sadness, anger, fear, surprise, frustration, and amusement). We show the results of three different supervised learning algorithms that categorize these collected signals in terms of emotions, and generalize their learning to recognize emotions from new collections of signals. We finally discuss possible broader impact and potential applications of emotion recognition for multimodal intelligent systems.

  9. A vision and strategy for the virtual physiological human in 2010 and beyond

    PubMed Central

    Hunter, Peter; Coveney, Peter V.; de Bono, Bernard; Diaz, Vanessa; Fenner, John; Frangi, Alejandro F.; Harris, Peter; Hose, Rod; Kohl, Peter; Lawford, Pat; McCormack, Keith; Mendes, Miriam; Omholt, Stig; Quarteroni, Alfio; Skår, John; Tegner, Jesper; Randall Thomas, S.; Tollis, Ioannis; Tsamardinos, Ioannis; van Beek, Johannes H. G. M.; Viceconti, Marco

    2010-01-01

    European funding under framework 7 (FP7) for the virtual physiological human (VPH) project has been in place now for nearly 2 years. The VPH network of excellence (NoE) is helping in the development of common standards, open-source software, freely accessible data and model repositories, and various training and dissemination activities for the project. It is also helping to coordinate the many clinically targeted projects that have been funded under the FP7 calls. An initial vision for the VPH was defined by framework 6 strategy for a European physiome (STEP) project in 2006. It is now time to assess the accomplishments of the last 2 years and update the STEP vision for the VPH. We consider the biomedical science, healthcare and information and communications technology challenges facing the project and we propose the VPH Institute as a means of sustaining the vision of VPH beyond the time frame of the NoE. PMID:20439264

  10. Audited credential delegation: a usable security solution for the virtual physiological human toolkit

    PubMed Central

    Haidar, Ali N.; Zasada, Stefan J.; Coveney, Peter V.; Abdallah, Ali E.; Beckles, Bruce; Jones, Mike A. S.

    2011-01-01

    We present applications of audited credential delegation (ACD), a usable security solution for authentication, authorization and auditing in distributed virtual physiological human (VPH) project environments that removes the use of digital certificates from end-users' experience. Current security solutions are based on public key infrastructure (PKI). While PKI offers strong security for VPH projects, it suffers from serious usability shortcomings in terms of end-user acquisition and management of credentials which deter scientists from exploiting distributed VPH environments. By contrast, ACD supports the use of local credentials. Currently, a local ACD username–password combination can be used to access grid-based resources while Shibboleth support is underway. Moreover, ACD provides seamless and secure access to shared patient data, tools and infrastructure, thus supporting the provision of personalized medicine for patients, scientists and clinicians participating in e-health projects from a local to the widest international scale. PMID:22670214

  11. Development of a Human Physiologically Based Pharmacokinetic (PBPK) Toolkit for Environmental Pollutants

    PubMed Central

    Ruiz, Patricia; Ray, Meredith; Fisher, Jeffrey; Mumtaz, Moiz

    2011-01-01

    Physiologically Based Pharmacokinetic (PBPK) models can be used to determine the internal dose and strengthen exposure assessment. Many PBPK models are available, but they are not easily accessible for field use. The Agency for Toxic Substances and Disease Registry (ATSDR) has conducted translational research to develop a human PBPK model toolkit by recoding published PBPK models. This toolkit, when fully developed, will provide a platform that consists of a series of priority PBPK models of environmental pollutants. Presented here is work on recoded PBPK models for volatile organic compounds (VOCs) and metals. Good agreement was generally obtained between the original and the recoded models. This toolkit will be available for ATSDR scientists and public health assessors to perform simulations of exposures from contaminated environmental media at sites of concern and to help interpret biomonitoring data. It can be used as screening tools that can provide useful information for the protection of the public. PMID:22174611

  12. HUMAN PARAOXONASE-1 (PON1): GENE STRUCTURE AND EXPRESSION, PROMISCUOUS ACTIVITIES AND MULTIPLE PHYSIOLOGICAL ROLES

    PubMed Central

    Mackness, Mike; Mackness, Bharti

    2015-01-01

    Human PON1 is a HDL-associated lipolactonase capable of preventing LDL and cell membrane oxidation and is therefore considered to be atheroprotective. PON1 contributes to the antioxidative function of HDL and reductions in HDL-PON1 activity, prevalent in a wide variety of diseases with an inflammatory component, is believed to lead to dysfunctional HDL which can promote inflammation and atherosclerosis. However, PON1 is multifunctional and may contribute to other HDL functions such as in innate immunity, preventing infection by quorum sensing gram negative bacteria by destroying acyl lactone mediators of quorum sensing, and putative new roles in cancer development and the promotion of healthy ageing. In this review we explore the physiological roles of PON1 in disease development, as well as PON1 gene and protein structure, promiscuous activities and the roles of SNPs and ethnicity in determining PON1 activity. PMID:25965560

  13. Physiologically based Pharmacokinetic Modeling of 1,4-Dioxane in Rats, Mice, and Humans

    SciTech Connect

    Sweeney, Lisa M.; Thrall, Karla D.; Poet, Torka S.; Corley, Rick; Weber, Thomas J.; Locey, B. J.; Clarkson, Jacquelyn; Sager, S.; Gargas, M. L.

    2008-01-01

    ABSTRACT 1,4-Dioxane (CAS No. 123-91-1) is used primarily as a solvent or as a solvent stabilizer. It can cause lung, liver and kidney damage at sufficiently high exposure levels. Two physiologically-based pharmacokinetic (PBPK) models of 1,4-dioxane and its major metabolite, hydroxyethoxyacetic acid (HEAA), were published in 1990. These models have uncertainties and deficiencies that could be addressed and the model strengthened for use in a contemporary cancer risk assessment for 1,4-dioxane. Studies were performed to fill data gaps and reduce uncertainties pertaining to the pharmacokinetics of 1,4-dioxane and HEAA in rats, mice, and humans. Three types of studies were performed:partition coefficient measurements, blood time course in mice, and in vitro pharmacokinetics using rat, mouse, and human hepatocytes. Updated PBPK models were developed based on these new data and previously available data. The optimized rate of metabolism for the mouse was significantly higher than the value previously estimated. The optimized rat kinetic parameters were similar to those in the 1990 models. Only two human studies were identified. Model predictions were consistent with one study, but did not fit the second as well. In addition, a rat nasal exposure was completed. The results confirmed water directly contacts rat nasal tissues during drinking water under bioassays. Consistent with previous PBPK models, nasal tissues were not specifically included in the model. Use of these models will reduce the uncertainty in future 1,4-dioxane risk assessments.

  14. Physiologically based pharmacokinetic modeling of ethyl acetate and ethanol in rodents and humans.

    PubMed

    Crowell, S R; Smith, J N; Creim, J A; Faber, W; Teeguarden, J G

    2015-10-01

    A physiologically based pharmacokinetic (PBPK) model was developed and applied to a metabolic series approach for the ethyl series (i.e., ethyl acetate, ethanol, acetaldehyde, and acetate). This approach bases toxicity information on dosimetry analyses for metabolically linked compounds using pharmacokinetic data for each compound and toxicity data for parent or individual compounds. In vivo pharmacokinetic studies of ethyl acetate and ethanol were conducted in rats following IV and inhalation exposure. Regardless of route, ethyl acetate was rapidly converted to ethanol. Blood concentrations of ethyl acetate and ethanol following both IV bolus and infusion suggested linear kinetics across blood concentrations from 0.1 to 10 mM ethyl acetate and 0.01-0.8 mM ethanol. Metabolic parameters were optimized and evaluated based on available pharmacokinetic data. The respiratory bioavailability of ethyl acetate and ethanol were estimated from closed chamber inhalation studies and measured ventilation rates. The resulting ethyl series model successfully reproduces blood ethyl acetate and ethanol kinetics following IV administration and inhalation exposure in rats, and blood ethanol kinetics following inhalation exposure to ethanol in humans. The extrapolated human model was used to derive human equivalent concentrations for the occupational setting of 257-2120 ppm ethyl acetate and 72-517 ppm ethyl acetate for continuous exposure, corresponding to rat LOAELs of 350 and 1500 ppm. PMID:26297692

  15. Physiological Content and Intrinsic Activities of 10 Cytochrome P450 Isoforms in Human Normal Liver Microsomes.

    PubMed

    Zhang, Hai-Feng; Wang, Huan-Huan; Gao, Na; Wei, Jun-Ying; Tian, Xin; Zhao, Yan; Fang, Yan; Zhou, Jun; Wen, Qiang; Gao, Jie; Zhang, Yang-Jun; Qian, Xiao-Hong; Qiao, Hai-Ling

    2016-07-01

    Due to a lack of physiologic cytochrome P450 (P450) isoform content, P450 activity is typically only determined at the microsomal level (per milligram of microsomal protein) and not at the isoform level (per picomole of P450 isoform), which could result in the misunderstanding of variations in P450 activity between individuals and further hinder development of personalized medicine. We found that there were large variations in protein content, mRNA levels, and intrinsic activities of the 10 P450s in 100 human liver samples, in which CYP2E1 and CYP2C9 showed the highest expression levels. P450 gene polymorphisms had different effects on activity at two levels: CYP3A5*3 and CYP2A6*9 alleles conferred increased activity at the isoform level but decreased activity at the microsomal level; CYP2C9*3 had no effect at the isoform level but decreased activity at the microsomal level. The different effects at each level stem from the different effects of each polymorphism on the resulting P450 protein. Individuals with CYP2A6*1/*4, CYP2A6*1/*9, CYP2C9*1/*3, CYP2D6 100C>T TT, CYP2E1 7632T>A AA, CYP3A5*1*3, and CYP3A5*3*3 genotypes had significantly lower protein content, whereas CYP2D6 1661G>C mutants had a higher protein content. In conclusion, we first offered the physiologic data of 10 P450 isoform contents and found that some single nucleotide polymorphisms had obvious effects on P450 expression in human normal livers. The effects of gene polymorphisms on intrinsic P450 activity at the isoform level were quite different from those at the microsomal level, which might be due to changes in P450 protein content. PMID:27189963

  16. [Human body composition during extended stay in microgravity].

    PubMed

    Noskov, V B; Nichiporuk, I A; Vasilieva, G Yu; Smirnov, Yu I

    2015-01-01

    According to the Sprut-2 protocol, bio-impedancemetry of ISS cosmonauts was performed once a month and also before and after mission. Multiple non-invasive body measurements were carried out in 15 cosmonauts in real time. Relocation of extracellular liquid along the body axis led to its reduction in legs and, on the contrary, an increase in the abdomen. Volumes of total body liquid as well as intra- and extracellular liquids decreased in comparison with pre-flight levels. Lean body mass also became less in microgravity, whereas fat mass showed an increase. PMID:25958462

  17. Fe and Cu isotope mass balances in the human body

    NASA Astrophysics Data System (ADS)

    Balter, V.; Albarede, F.; Jaouen, K.

    2011-12-01

    The ranges of the Fe and Cu isotope compositions in the human body are large, i.e. ~3% and ~2%, respectively. Both isotopic fractionations appear to be mainly controlled by redox conditions. The Fe and Cu isotope compositions of the tissues analyzed so far plot on a mixing hyperbolae between a reduced and an oxidized metals pools. The reduced metals pool is composed by erythrocytes, where Fe is bounded to hemoglobin as Fe(II) and Cu to superoxide-dismutase as Cu(I). The oxidized metals pool is composed by hepatocytes, where Fe and Cu are stored as Fe(III) ferritin and as Cu(II) ceruloplasmine, respectively. The position of each biological component in the δ56Fe-δ65Cu diagram therefore reflects the oxidation state of Fe and Cu of the predominant metal carrier protein and allows to quantify Fe and Cu fluxes between organs using mass balance calculations. For instance, serum and clot Fe and Cu isotope compositions show that current biological models of erythropoiesis violates mass conservation requirements, and suggest hidden Fe and Cu pathways during red blood cells synthesis. The results also show that a coupled Fe-Cu strong gender isotopic effect is observed in various organs. The isotopic difference between men and women is unlikely to be due to differential dietary uptake or endometrium loss, but rather reflects the effect of menstrual losses and a correlative solicitation of hepatic stores. We speculate that thorough studies of the metabolism of stable isotopes in normal conditions is a prerequisite for the understanding of the pathological dysregulations.

  18. Human perceptual overestimation of whole body roll tilt in hypergravity

    PubMed Central

    Newman, Michael C.; Oman, Charles M.; Merfeld, Daniel M.; Young, Laurence R.

    2014-01-01

    Hypergravity provides a unique environment to study human perception of orientation. We utilized a long-radius centrifuge to study perception of both static and dynamic whole body roll tilt in hypergravity, across a range of angles, frequencies, and net gravito-inertial levels (referred to as G levels). While studies of static tilt perception in hypergravity have been published, this is the first to measure dynamic tilt perception (i.e., with time-varying canal stimulation) in hypergravity using a continuous matching task. In complete darkness, subjects reported their orientation perception using a haptic task, whereby they attempted to align a hand-held bar with their perceived horizontal. Static roll tilt was overestimated in hypergravity, with more overestimation at larger angles and higher G levels, across the conditions tested (overestimated by ∼35% per additional G level, P < 0.001). As our primary contribution, we show that dynamic roll tilt was also consistently overestimated in hypergravity (P < 0.001) at all angles and frequencies tested, again with more overestimation at higher G levels. The overestimation was similar to that for static tilts at low angular velocities but decreased at higher angular velocities (P = 0.006), consistent with semicircular canal sensory integration. To match our findings, we propose a modification to a previous Observer-type canal-otolith interaction model. Specifically, our data were better modeled by including the hypothesis that the central nervous system treats otolith stimulation in the utricular plane differently than stimulation out of the utricular plane. This modified model was able to simulate quantitatively both the static and the dynamic roll tilt overestimation in hypergravity measured experimentally. PMID:25540216

  19. Representational Momentum for the Human Body: Awkwardness Matters, Experience Does Not

    ERIC Educational Resources Information Center

    Wilson, Margaret; Lancaster, Jessy; Emmorey, Karen

    2010-01-01

    Perception of the human body appears to involve predictive simulations that project forward to track unfolding body-motion events. Here we use representational momentum (RM) to investigate whether implicit knowledge of a learned arbitrary system of body movement such as sign language influences this prediction process, and how this compares to…

  20. In vivo Whole-Cell Recordings Combined with Electron Microscopy Reveal Unexpected Morphological and Physiological Properties in the Lateral Nucleus of the Trapezoid Body in the Auditory Brainstem

    PubMed Central

    Franken, Tom P.; Smith, Philip H.; Joris, Philip X.

    2016-01-01

    The lateral nucleus of the trapezoid body (LNTB) is a prominent nucleus in the superior olivary complex in mammals including humans. Its physiology in vivo is poorly understood due to a paucity of recordings. It is thought to provide a glycinergic projection to the medial superior olive (MSO) with an important role in binaural processing and sound localization. We combined in vivo patch clamp recordings with labeling of individual neurons in the Mongolian gerbil. Labeling of the recorded neurons allowed us to relate physiological properties to anatomy at the light and electron microscopic level. We identified a population of quite dorsally located neurons with surprisingly large dendritic trees on which most of the synaptic input impinges. In most neurons, one or more of these dendrites run through and are then medial to the MSO. These neurons were often binaural and could even show sensitivity to interaural time differences (ITDs) of stimulus fine structure or envelope. Moreover, a subpopulation showed enhanced phase-locking to tones delivered in the tuning curve tail. We propose that these neurons constitute the gerbil main LNTB (mLNTB). In contrast, a smaller sample of neurons was identified that was located more ventrally and that we designate to be in posteroventral LNTB (pvLNTB). These cells receive large somatic excitatory terminals from globular bushy cells. We also identified previously undescribed synaptic inputs from the lateral superior olive. pvLNTB neurons are usually monaural, display a primary-like-with-notch response to ipsilateral short tones at CF and can phase-lock to low frequency tones. We conclude that mLNTB contains a population of neurons with extended dendritic trees where most of the synaptic input is found, that can show enhanced phase-locking and sensitivity to ITD. pvLNTB cells, presumed to provide glycinergic input to the MSO, get large somatic globular bushy synaptic inputs and are typically monaural with short tone responses similar

  1. In vivo Whole-Cell Recordings Combined with Electron Microscopy Reveal Unexpected Morphological and Physiological Properties in the Lateral Nucleus of the Trapezoid Body in the Auditory Brainstem.

    PubMed

    Franken, Tom P; Smith, Philip H; Joris, Philip X

    2016-01-01

    The lateral nucleus of the trapezoid body (LNTB) is a prominent nucleus in the superior olivary complex in mammals including humans. Its physiology in vivo is poorly understood due to a paucity of recordings. It is thought to provide a glycinergic projection to the medial superior olive (MSO) with an important role in binaural processing and sound localization. We combined in vivo patch clamp recordings with labeling of individual neurons in the Mongolian gerbil. Labeling of the recorded neurons allowed us to relate physiological properties to anatomy at the light and electron microscopic level. We identified a population of quite dorsally located neurons with surprisingly large dendritic trees on which most of the synaptic input impinges. In most neurons, one or more of these dendrites run through and are then medial to the MSO. These neurons were often binaural and could even show sensitivity to interaural time differences (ITDs) of stimulus fine structure or envelope. Moreover, a subpopulation showed enhanced phase-locking to tones delivered in the tuning curve tail. We propose that these neurons constitute the gerbil main LNTB (mLNTB). In contrast, a smaller sample of neurons was identified that was located more ventrally and that we designate to be in posteroventral LNTB (pvLNTB). These cells receive large somatic excitatory terminals from globular bushy cells. We also identified previously undescribed synaptic inputs from the lateral superior olive. pvLNTB neurons are usually monaural, display a primary-like-with-notch response to ipsilateral short tones at CF and can phase-lock to low frequency tones. We conclude that mLNTB contains a population of neurons with extended dendritic trees where most of the synaptic input is found, that can show enhanced phase-locking and sensitivity to ITD. pvLNTB cells, presumed to provide glycinergic input to the MSO, get large somatic globular bushy synaptic inputs and are typically monaural with short tone responses similar

  2. Mapping multisensory parietal face and body areas in humans.

    PubMed

    Huang, Ruey-Song; Chen, Ching-fu; Tran, Alyssa T; Holstein, Katie L; Sereno, Martin I

    2012-10-30

    Detection and avoidance of impending obstacles is crucial to preventing head and body injuries in daily life. To safely avoid obstacles, locations of objects approaching the body surface are usually detected via the visual system and then used by the motor system to guide defensive movements. Mediating between visual input and motor output, the posterior parietal cortex plays an important role in integrating multisensory information in peripersonal space. We used functional MRI to map parietal areas that see and feel multisensory stimuli near or on the face and body. Tactile experiments using full-body air-puff stimulation suits revealed somatotopic areas of the face and multiple body parts forming a higher-level homunculus in the superior posterior parietal cortex. Visual experiments using wide-field looming stimuli revealed retinotopic maps that overlap with the parietal face and body areas in the postcentral sulcus at the most anterior border of the dorsal visual pathway. Starting at the parietal face area and moving medially and posteriorly into the lower-body areas, the median of visual polar-angle representations in these somatotopic areas gradually shifts from near the horizontal meridian into the lower visual field. These results suggest the parietal face and body areas fuse multisensory information in peripersonal space to guard an individual from head to toe. PMID:23071340

  3. Computerized Simulation Of Whole Body Dynamics: Aspects Of Human Movement Modeling

    NASA Astrophysics Data System (ADS)

    Huston, Ronald L.; Zernicke, Ronald F.

    1982-02-01

    Recent developments in the modeling of multi-body system dynamics are incorporated into an integrated, computer-oriented method for analyzing human body motion. The formulation, which represents the human body as a set of 17 finite, rigid-body segments including hands, feet, arms, legs, head, neck, and upper and lower torso, also accounts for the effects of connective tissues and muscles with non-linear springs and dampers at the connections of the linked rigid-bodies. Specific application of this biomathematical modeling of the body segments includes the estimation of musculoskeletal injury potential during aircraft and land vehicular crashes. With the integration of the output dynamics of the model, the injury profiles of the occupants, and human tissue tolerance limits, a more complete analysis and reconstruction of the details of the human occupant trajectory responses and injury incurrence can be made.

  4. Ethical, anatomical and physiological issues in developing vestibular implants for human use.

    PubMed

    Guyot, Jean-Philippe; Gay, Annietta; Kos, Maria Izabel; Pelizzone, Marco

    2012-01-01

    Effort towards the development of a vestibular implant for human use are being made. This paper will summarize the first important steps conducted in Geneva towards this ambitious goal. Basically, we have faced three major issues. First, an ethical issue. While it was clear that such development would require the collaboration of human volunteers, it was also clear that stimulation of the vestibular system may produce periods of significant incomfort. We know today how to minimize (and potentially eliminate) this type of incomfort. The second issue was anatomical. The anatomical topology of the vestibular system is complex, and of potentially dangerous access (i.e. facial nerve damage). We choose not to place the electrodes inside the ampullae but close the vestibular nerve branches, to avoid any opening of the inner ear and limit the risk of hearing loss. Work on cadaver heads, confirmed by acute stimulations trials on patients undergoing ear surgery under local anesthesia, demonstrated that it is possible to stimulate selectively both the posterior and lateral ampullary nerves, and elicit the expected vertical and horizontal nystagmic responses. The third issue was physiological. One of the goal of a vestibular implant will be to produce smooth eye movements to stabilize gaze direction when the head is moving. Indeed, after restoring a baseline or "rest" activity in the vestibular pathways with steady-state electrical stimulation, we demonstrated that modulation of this stimulation is producing smooth eye movements. In conclusion, humans can adapt to electrical stimulation of the vestibular system without too much discomfort. Surgical access to the posterior and lateral ampullary nerves have been developed and, electrical stimulation of the vestibular system can be used to artificially elicit smooth eye movements of different speeds and directions, once the system is in adapted state. Therefore, the major prerequisites to develop a prototype vestibular implant

  5. Human body motion tracking based on quantum-inspired immune cloning algorithm

    NASA Astrophysics Data System (ADS)

    Han, Hong; Yue, Lichuan; Jiao, Licheng; Wu, Xing

    2009-10-01

    In a static monocular camera system, to gain a perfect 3D human body posture is a great challenge for Computer Vision technology now. This paper presented human postures recognition from video sequences using the Quantum-Inspired Immune Cloning Algorithm (QICA). The algorithm included three parts. Firstly, prior knowledge of human beings was used, the key joint points of human could be detected automatically from the human contours and skeletons which could be thinning from the contours; And due to the complexity of human movement, a forecasting mechanism of occlusion joint points was addressed to get optimum 2D key joint points of human body; And then pose estimation recovered by optimizing between the 2D projection of 3D human key joint points and 2D detection key joint points using QICA, which recovered the movement of human body perfectly, because this algorithm could acquire not only the global optimal solution, but the local optimal solution.

  6. Physiologic time: A hypothesis

    NASA Astrophysics Data System (ADS)

    West, Damien; West, Bruce J.

    2013-06-01

    The scaling of respiratory metabolism with body size in animals is considered by many to be a fundamental law of nature. One apparent consequence of this law is the scaling of physiologic time with body size, implying that physiologic time is separate and distinct from clock time. Physiologic time is manifest in allometry relations for lifespans, cardiac cycles, blood volume circulation, respiratory cycle, along with a number of other physiologic phenomena. Herein we present a theory of physiologic time that explains the allometry relation between time and total body mass averages as entailed by the hypothesis that the fluctuations in the total body mass are described by a scaling probability density.

  7. Variability in cardiac electrophysiology: Using experimentally-calibrated populations of models to move beyond the single virtual physiological human paradigm

    PubMed Central

    Muszkiewicz, Anna; Britton, Oliver J.; Gemmell, Philip; Passini, Elisa; Sánchez, Carlos; Zhou, Xin; Carusi, Annamaria; Quinn, T. Alexander; Burrage, Kevin; Bueno-Orovio, Alfonso; Rodriguez, Blanca

    2016-01-01

    Physiological variability manifests itself via differences in physiological function between individuals of the same species, and has crucial implications in disease progression and treatment. Despite its importance, physiological variability has traditionally been ignored in experimental and computational investigations due to averaging over samples from multiple individuals. Recently, modelling frameworks have been devised for studying mechanisms underlying physiological variability in cardiac electrophysiology and pro-arrhythmic risk under a variety of conditions and for several animal species as well as human. One such methodology exploits populations of cardiac cell models constrained with experimental data, or experimentally-calibrated populations of models. In this review, we outline the considerations behind constructing an experimentally-calibrated population of models and review the studies that have employed this approach to investigate variability in cardiac electrophysiology in physiological and pathological conditions, as well as under drug action. We also describe the methodology and compare it with alternative approaches for studying variability in cardiac electrophysiology, including cell-specific modelling approaches, sensitivity-analysis based methods, and populations-of-models frameworks that do not consider the experimental calibration step. We conclude with an outlook for the future, predicting the potential of new methodologies for patient-specific modelling extending beyond the single virtual physiological human paradigm. PMID:26701222

  8. Chemoreflex Physiology and Implications for Sleep Apnea – Insights from Studies in Humans

    PubMed Central

    Mansukhani, Meghna P.; Wang, Shihan; Somers, Virend K.

    2015-01-01

    Activation of the chemoreflex in response to hypoxemia results in an increase in sympathetic neural outflow. This process is predominantly mediated by the peripheral chemoreceptors in the carotid bodies and is potentiated by the absence of the sympatho-inhibitory influence of ventilation during apnea, as is seen in patients with sleep apnea. In these patients, repetitive nocturnal hyoxemia and apnea elicit sympathetic activation, which may persist into wakefulness, and is thought to contribute to the development of systemic hypertension, and cardiac and vascular dysfunction. Chemoreflex activation could possibly lead to adverse cardiovascular outcomes such as nocturnal myocardial infarction, systolic and/or diastolic heart failure, cardiac arrhythmias and sudden death in patients with sleep apnea. This review summarizes chemoreflex physiology in health and disease, with specific focus on chemoreflex-mediated pathophysiology in obstructive and central sleep apnea. Measurement of the chemoreflex response may serve as a potential avenue for individualized screening for cardiovascular disease. Whether modulation of this response in sleep apnea may aid in the prevention and treatment of adverse cardiovascular consequences will require further study. PMID:25398715

  9. Regulation of lipid deposition in farm animals: Parallels between agriculture and human physiology.

    PubMed

    Bergen, Werner G; Brandebourg, Terry D

    2016-06-01

    For many years, clinically oriented scientists and animal scientists have focused on lipid metabolism and fat deposition in various fat depots. While dealing with a common biology across species, the goals of biomedical and food animals lipid metabolism research differ in emphasis. In humans, mechanisms and regulation of fat synthesis, accumulation of fat in regional fat depots, lipid metabolism and dysmetabolism in adipose, liver and cardiac tissues have been investigated. Further, energy balance and weight control have also been extensively explored in humans. Finally, obesity and associated maladies including high cholesterol and atherosclerosis, cardiovascular disease, insulin resistance, hypertension, metabolic syndrome and health outcomes have been widely studied. In food animals, the emphasis has been on regulation of fatty acid synthesis and lipid deposition in fat depots and deposition of intramuscular fat. For humans, understanding the regulation of energy balance and body weight and of prevention or treatment of obesity and associated maladies have been important clinical outcomes. In production of food animals lowering fat content in muscle foods while enhancing intramuscular fat (marbling) have been major targets. In this review, we summarize how our laboratories have addressed the goal of providing lean but yet tasty and juicy muscle food products to consumers. In addition, we here describe efforts in the development of a new porcine model to study regulation of fat metabolism and obesity. Commonalities and differences in regulation of lipid metabolism between humans, rodents and food animals are emphasized throughout this review. PMID:27302175

  10. A human liver microphysiology platform for investigating physiology, drug safety, and disease models.

    PubMed

    Vernetti, Lawrence A; Senutovitch, Nina; Boltz, Robert; DeBiasio, Richard; Shun, Tong Ying; Gough, Albert; Taylor, D Lansing

    2016-01-01

    This paper describes the development and characterization of a microphysiology platform for drug safety and efficacy in liver models of disease that includes a human, 3D, microfluidic, four-cell, sequentially layered, self-assembly liver model (SQL-SAL); fluorescent protein biosensors for mechanistic readouts; as well as a microphysiology system database (MPS-Db) to manage, analyze, and model data. The goal of our approach is to create the simplest design in terms of cells, matrix materials, and microfluidic device parameters that will support a physiologically relevant liver model that is robust and reproducible for at least 28 days for stand-alone liver studies and microfluidic integration with other organs-on-chips. The current SQL-SAL uses primary human hepatocytes along with human endothelial (EA.hy926), immune (U937) and stellate (LX-2) cells in physiological ratios and is viable for at least 28 days under continuous flow. Approximately, 20% of primary hepatocytes and/or stellate cells contain fluorescent protein biosensors (called sentinel cells) to measure apoptosis, reactive oxygen species (ROS) and/or cell location by high content analysis (HCA). In addition, drugs, drug metabolites, albumin, urea and lactate dehydrogenase (LDH) are monitored in the efflux media. Exposure to 180 μM troglitazone or 210 μM nimesulide produced acute toxicity within 2-4 days, whereas 28 μM troglitazone produced a gradual and much delayed toxic response over 21 days, concordant with known mechanisms of toxicity, while 600 µM caffeine had no effect. Immune-mediated toxicity was demonstrated with trovafloxacin with lipopolysaccharide (LPS), but not levofloxacin with LPS. The SQL-SAL exhibited early fibrotic activation in response to 30 nM methotrexate, indicated by increased stellate cell migration, expression of alpha-smooth muscle actin and collagen, type 1, alpha 2. Data collected from the in vitro model can be integrated into a database with access to related

  11. A human liver microphysiology platform for investigating physiology, drug safety, and disease models

    PubMed Central

    Vernetti, Lawrence A.; Senutovitch, Nina; Boltz, Robert; DeBiasio, Richard; Shun, Tong Ying; Gough, Albert; Taylor, D. Lansing

    2015-01-01

    This paper describes the development and characterization of a microphysiology platform for drug safety and efficacy in liver models of disease that includes a human, 3D, microfluidic, four-cell, sequentially layered, self-assembly liver model (SQL-SAL); fluorescent protein biosensors for mechanistic readouts; as well as a microphysiology system database (MPS-Db) to manage, analyze, and model data. The goal of our approach is to create the simplest design in terms of cells, matrix materials, and microfluidic device parameters that will support a physiologically relevant liver model that is robust and reproducible for at least 28 days for stand-alone liver studies and microfluidic integration with other organs-on-chips. The current SQL-SAL uses primary human hepatocytes along with human endothelial (EA.hy926), immune (U937) and stellate (LX-2) cells in physiological ratios and is viable for at least 28 days under continuous flow. Approximately, 20% of primary hepatocytes and/or stellate cells contain fluorescent protein biosensors (called sentinel cells) to measure apoptosis, reactive oxygen species (ROS) and/or cell location by high content analysis (HCA). In addition, drugs, drug metabolites, albumin, urea and lactate dehydrogenase (LDH) are monitored in the efflux media. Exposure to 180μM troglitazone or 210μM nimesulide produced acute toxicity within 2–4 days, whereas 28μM troglitazone produced a gradual and much delayed toxic response over 21 days, concordant with known mechanisms of toxicity, while 600μM caffeine had no effect. Immune-mediated toxicity was demonstrated with trovafloxacin with lipopolysaccharide (LPS), but not levofloxacin with LPS. The SQL-SAL exhibited early fibrotic activation in response to 30nM methotrexate, indicated by increased stellate cell migration, expression of alpha-smooth muscle actin and collagen, type 1, alpha 2. Data collected from the in vitro model can be integrated into a database with access to related chemical

  12. Effects of foliage plants on human physiological and psychological responses at different temperatures

    NASA Astrophysics Data System (ADS)

    Jumeno, Desto; Matsumoto, Hiroshi

    2015-02-01

    Escalation of task demands and time pressures tends to make a worker run into work stress, which leads to mental fatigue and depression. The mental fatigue can be reduced when attention capacity is restored. Nature can serve as a source of fascination which can restore the attention capacity. People bring plants indoors so they can experience nature in their workplace. The stress and fatigue are also affected by air temperatures. The increase or decrease of temperatures from the comfort zone may induce the stress and fatigue. The objective of this study is to investigate the intervention of using foliage plants placed inside a building at different air temperature levels. The effects of foliage plants on human stress and fatigue were measured by human physiological responses such as heart rate, amylase level, electroencephalography (EEG), and the secondary task-reaction time. Several different tasks, namely typing, math and logical sequences are included in the investigation of these studies. Fifteen subjects, with the age ranged from 22 to 38 years old have participated in the study using within subject design. From the study, it is revealed that the presence of foliage plants at several temperatures have different effects on meditation, secondary task reaction time and typing accuracy. This study also revealed that the presence of plants on several types of tasks has different effects of attention which are useful for increasing work performance.

  13. A wireless capsule system with ASIC for monitoring the physiological signals of the human gastrointestinal tract.

    PubMed

    Xu, Fei; Yan, Guozheng; Zhao, Kai; Lu, Li; Gao, Jinyang; Liu, Gang

    2014-12-01

    This paper presents the design of a wireless capsule system for monitoring the physiological signals of the human gastrointestinal (GI) tract. The primary components of the system include a wireless capsule, a portable data recorder, and a workstation. Temperature, pH, and pressure sensors; an RF transceiver; a controlling and processing application specific integrated circuit (ASIC); and batteries were applied in a wireless capsule. Decreasing capsule size, improving sensor precision, and reducing power needs were the primary challenges; these were resolved by employing micro sensors, optimized architecture, and an ASIC design that include power management, clock management, a programmable gain amplifier (PGA), an A/D converter (ADC), and a serial peripheral interface (SPI) communication unit. The ASIC has been fabricated in 0.18- μm CMOS technology with a die area of 5.0 mm × 5.0 mm. The wireless capsule integrating the ASIC controller measures Φ 11 mm × 26 mm. A data recorder and a workstation were developed, and 20 cases of human experiments were conducted in hospitals. Preprocessing in the workstation can significantly improve the quality of the data, and 76 original features were determined by mathematical statistics. Based on the 13 optimal features achieved in the evaluation of the features, the clustering algorithm can identify the patients who lack GI motility with a recognition rate reaching 83.3%. PMID:25608285

  14. Muscle sympathetic nerve responses to physiological changes in prostaglandin production in humans

    NASA Technical Reports Server (NTRS)

    Doerzbacher, K. J.; Ray, C. A.

    2001-01-01

    Previous studies suggest that prostaglandins may contribute to exercise-induced increases in muscle sympathetic nerve activity (MSNA). To test this hypothesis, MSNA was measured at rest and during exercise before and after oral administration of ketoprofen, a cyclooxygenase inhibitor, or placebo. Twenty-one subjects completed two bouts of graded dynamic and isometric handgrip to fatigue. Each exercise bout was followed by 2 min of postexercise muscle ischemia. The second exercise bouts were performed after 60 min of rest in which 11 subjects were given ketoprofen (300 mg) and 10 subjects received a placebo. Ketoprofen significantly lowered plasma thromboxane B(2) in the drug group (from 36 +/- 6 to 22 +/- 3 pg/ml, P < 0.04), whereas thromboxane B(2) in the placebo group increased from 40 +/- 5 to 61 +/- 9 pg/ml from trial 1 to trial 2 (P < 0.008). Ketoprofen and placebo did not change sympathetic and cardiovascular responses to dynamic handgrip, isometric handgrip, and postexercise muscle ischemia. There was no relationship between thromboxane B(2) concentrations and MSNA or arterial pressure responses during both exercise modes. The data indicate that physiological increases or decreases in prostaglandins do not alter exercise-induced increases in MSNA and arterial pressure in humans. These findings suggest that contraction-induced metabolites other than prostaglandins mediate MSNA responses to exercise in humans.

  15. Multicarotenoids at Physiological Levels Inhibit Metastasis in Human Hepatocarcinoma SK-Hep-1 Cells.

    PubMed

    Chen, Huei-Yan; Yang, Chih-Min; Chen, Jen-Yin; Yueh, Te-Cheng; Hu, Miao-Lin

    2015-01-01

    Several studies have demonstrated that single carotenoid, including lycopene, β-carotene, and α-carotene, exhibits antimetastatic effects; however, little is known whether multicarotenoids have similar effects. Herein, we investigated the antimetastatic effect of multicarotenoids at physiological serum levels in Taiwanese (MCT at 1.4 μM) and American (MCA at 1.8 μM) populations using human hepatocarcinoma SK-Hep-1 cells in comparison with single carotenoid, such as lycopene (0.3 or 0.6 μM, respectively), α-carotene (0.1 μM), β-carotene (0.4 μM), lutein (0.4 or 0.5 μM, respectively), and β-cryptoxanthin (0.2 μM). Results reveal that MCA treatment exhibited an additive inhibition on invasion, migration and adhesion at 24 and 48 h of incubation, whereas MCT treatment possessed additive inhibition at 48 h of incubation. The antimetastatic action of MCT and MCA involved additive reduction on activities of matrix metalloproteinase (MMP)-2, -9, and protein expression of Rho and Rac 1 but additive promotion on protein expression of tissue inhibitor of MMP (TIMP)-1 and -2. All of these effects were stronger in MCA than in MCT at 24 and 48 h of incubation. These results demonstrate that multi-carotenoids effectively inhibit metastasis of human hepatocarcinoma SK-Hep-1 cells. More in vivo studies are needed to confirm these findings. PMID:25868689

  16. Tensor body: real-time reconstruction of the human body and avatar synthesis from RGB-D.

    PubMed

    Barmpoutis, Angelos

    2013-10-01

    Real-time 3-D reconstruction of the human body has many applications in anthropometry, telecommunications, gaming, fashion, and other areas of human-computer interaction. In this paper, a novel framework is presented for reconstructing the 3-D model of the human body from a sequence of RGB-D frames. The reconstruction is performed in real time while the human subject moves arbitrarily in front of the camera. The method employs a novel parameterization of cylindrical-type objects using Cartesian tensor and b-spline bases along the radial and longitudinal dimension respectively. The proposed model, dubbed tensor body, is fitted to the input data using a multistep framework that involves segmentation of the different body regions, robust filtering of the data via a dynamic histogram, and energy-based optimization with positive-definite constraints. A Riemannian metric on the space of positive-definite tensor splines is analytically defined and employed in this framework. The efficacy of the presented methods is demonstrated in several real-data experiments using the Microsoft Kinect sensor. PMID:23974673

  17. The Effects of an Olive Fruit Polyphenol-Enriched Yogurt on Body Composition, Blood Redox Status, Physiological and Metabolic Parameters and Yogurt Microflora

    PubMed Central

    Georgakouli, Kalliopi; Mpesios, Anastasios; Kouretas, Demetrios; Petrotos, Konstantinos; Mitsagga, Chrysanthi; Giavasis, Ioannis; Jamurtas, Athanasios Z.

    2016-01-01

    In the present study we investigated the effects of an olive polyphenol-enriched yogurt on yogurt microflora, as well as hematological, physiological and metabolic parameters, blood redox status and body composition. In a randomized double-blind, crossover design, 16 (6 men, 10 women) nonsmoking volunteers with non-declared pathology consumed either 400 g of olive fruit polyphenol-enriched yogurt with 50 mg of encapsulated olive polyphenols (experimental condition—EC) or 400 g of plain yogurt (control condition—CC) every day for two weeks. Physiological measurements and blood collection were performed before and after two weeks of each condition. The results showed that body weight, body mass index, hip circumference and systolic blood pressure decreased significantly (p < 0.05) following the two-week consumption of yogurt regardless of condition. A tendency towards significance for decreased levels of low density lipoprotein (LDL) cholesterol (p = 0.06) and thiobarbituric acid reactive substances (p < 0.05) following two weeks of polyphenol-enriched yogurt consumption was observed. The population of lactic acid bacteria (LAB) and production of lactate in yogurt were significantly enhanced after addition of olive polyphenols, contrary to the population of yeasts and molds. The results indicate that consumption of the polyphenol-enriched yogurt may help individuals with non-declared pathology reduce body weight, blood pressure, LDL cholesterol levels and lipid peroxidation, and promote growth of beneficial LAB. PMID:27271664

  18. The Effects of an Olive Fruit Polyphenol-Enriched Yogurt on Body Composition, Blood Redox Status, Physiological and Metabolic Parameters and Yogurt Microflora.

    PubMed

    Georgakouli, Kalliopi; Mpesios, Anastasios; Kouretas, Demetrios; Petrotos, Konstantinos; Mitsagga, Chrysanthi; Giavasis, Ioannis; Jamurtas, Athanasios Z

    2016-01-01

    In the present study we investigated the effects of an olive polyphenol-enriched yogurt on yogurt microflora, as well as hematological, physiological and metabolic parameters, blood redox status and body composition. In a randomized double-blind, crossover design, 16 (6 men, 10 women) nonsmoking volunteers with non-declared pathology consumed either 400 g of olive fruit polyphenol-enriched yogurt with 50 mg of encapsulated olive polyphenols (experimental condition-EC) or 400 g of plain yogurt (control condition-CC) every day for two weeks. Physiological measurements and blood collection were performed before and after two weeks of each condition. The results showed that body weight, body mass index, hip circumference and systolic blood pressure decreased significantly (p < 0.05) following the two-week consumption of yogurt regardless of condition. A tendency towards significance for decreased levels of low density lipoprotein (LDL) cholesterol (p = 0.06) and thiobarbituric acid reactive substances (p < 0.05) following two weeks of polyphenol-enriched yogurt consumption was observed. The population of lactic acid bacteria (LAB) and production of lactate in yogurt were significantly enhanced after addition of olive polyphenols, contrary to the population of yeasts and molds. The results indicate that consumption of the polyphenol-enriched yogurt may help individuals with non-declared pathology reduce body weight, blood pressure, LDL cholesterol levels and lipid peroxidation, and promote growth of beneficial LAB. PMID:27271664

  19. Thermoregulatory physiologic responses in the human body exposed to microwave radiation

    SciTech Connect

    Way, W.I.; Kritikos, H.; Schwan, H.

    1981-01-01

    By introduction of an additional compartment in the hypothalamic region Stolwijk's thermoregulatory model has been modified to consider partial heating due to hot spots induced by microwaves. It was found that because of thermoregulatory action, the temperature of the hypothalamus will not increase drastically until the rate of energy deposition exceeds the threshold level of about 50 mW/g. The primary controlling mechanisms are blood flow and sweating. For an energy deposition rate of 10 mW/g in the hypothalamus the increase in blood flow in the skin is negligible and the temperature rise of the hypothalamus as compared with blood temperature is about 0.5/sup 0/C. It was found that exposure of the head to electromagnetic radiation, in general, causes a decrease in temperature of the trunk and skin. The results show that while the deposition of energy in the hypothalamus at the rate of 10 mW/g produced significant conductive and convective effects, the same total energy uniformly distributed over the cranial cavity produces less significant effects.

  20. Using and respecting the dead human body: an anatomist's perspective.

    PubMed

    Jones, D Gareth

    2014-09-01

    In his stimulating article enquiring into what the living owe the dead, Wilkinson (2013, Clin. Anat. DOI: 10.1002/ca.22263) sought to unpack a range of ethical questions of considerable interest to anatomists. In this, he looked closely at the extent to which we are or are not to respect all the prior wishes of the deceased, and the implications of this for the role of the family in providing consent, the use of unclaimed bodies, and the public display of bodies. Some of his conclusions challenge widely encountered views by anatomists. In this response I have re-visited these topics in an attempt to ground his arguments in the experience of anatomists, by emphasizing the many intimate connections that exist between each of these areas. The following emerge as issues for further debate. I accept that the wishes of the deceased are preeminent, so that authorities should make every effort to abide by these. This reiterates the importance of body bequests over against unclaimed bodies, and provides a context for assessing the role of family consent. This has repercussions for all activities employing dead bodies, from the dissecting room to public plastination exhibitions. In determining the extent to which the wishes of the deceased are followed the input of other interested parties is a relevant consideration. An ethical assessment of the public display of bodies needs to take into account the nature of the plastination process. PMID:24753363

  1. Validation of Human Body Model VIRTHUMAN and its Implementation in Crash Scenarios

    NASA Astrophysics Data System (ADS)

    Jaroslav Maňas, Ing.; Luděk Kovář, Ing.; Jan Petřík, Ing.; Hana Čechová, Ing.; Stanislav Špirk, Ing.

    Standard virtual prototyping approach of passive safety field is based on virtual models of dummies, but human body models become to be more and more important for specific crash scenarios. VIRTHUMAN is human body model based on MBS (Multi-Body Structure) approach. The model consists of movable rigid segments, which represent proper mass of each human part and enables to evaluate injury criteria describing safety risks during crash scenarios. There is evident advantage of the MBS approach in simple preparation of crash configuration—human body positioning, reasonable calculation times and mainly its applicability for robust designs development respecting variety of human population. The project VIRTHUMAN is directed on development of scaling technique enabling to generate human model based on the standard anthropometric inputs. The contribution describes status of the VIRTHUMAN model, procedures of its validation and results in standard crash scenarios.

  2. Evaluation of human interindividual variation in bioactivation of estragole using physiologically based biokinetic modeling.

    PubMed

    Punt, Ans; Jeurissen, Suzanne M; Boersma, Marelle G; Delatour, Thierry; Scholz, Gabriele; Schilter, Benoît; van Bladeren, Peter J; Rietjens, Ivonne M C M

    2010-02-01

    The present study investigates interindividual variation in liver levels of the proximate carcinogenic metabolite of estragole, 1'-hydroxyestragole, due to variation in two key metabolic reactions involved in the formation and detoxification of this metabolite, namely 1'-hydroxylation of estragole and oxidation of 1'-hydroxyestragole. Formation of 1'-hydroxyestragole is predominantly catalyzed by P450 1A2, 2A6, and 2E1, and results of the present study support that oxidation of 1'-hydroxyestragole is catalyzed by 17beta-hydroxysteroid dehydrogenase type 2 (17beta-HSD2). In a first approach, the study defines physiologically based biokinetic (PBBK) models for 14 individual human subjects, revealing a 1.8-fold interindividual variation in the area under the liver concentration-time curve (AUC) for 1'-hydroxyestragole within this group of human subjects. Variation in oxidation of 1'-hydroxyestragole by 17beta-HSD2 was shown to result in larger effects than those caused by variation in P450 enzyme activity. In a second approach, a Monte Carlo simulation was performed to evaluate the extent of variation in liver levels of 1'-hydroxyestragole that could occur in the population as a whole. This analysis could be used to derive a chemical-specific adjustment factor (CSAF), which is defined as the 99th percentile divided by the 50th percentile of the predicted distribution of the AUC of 1'-hydroxyestragole in the liver. The CSAF was estimated to range between 1.6 and 4.0, depending on the level of variation that was taken into account for oxidation of 1'-hydroxyestragole. Comparison of the CSAF to the default uncertainty factor of 3.16 for human variability in biokinetics reveals that the default uncertainty factor adequately protects 99% of the population. PMID:19920071

  3. The human sperm acrosome reaction: physiology and regulatory mechanisms. An update.

    PubMed

    Brucker, C; Lipford, G B

    1995-01-01

    The acrosome reaction is a crucial step during gamete interaction in all species, including man. It allows spermatozoa to penetrate the zona pellucida and fuse with the oocyte membrane. Spermatozoa unable to undergo the acrosome reaction will not fertilize intact oocytes. This article concentrates on the characteristics and regulatory mechanisms of the acrosome reaction in human spermatozoa. During recent years, various entities found in the vicinity of the ovulated oocyte have been identified as stimulators of the acrosome reaction, of which zona protein is considered the prime physiological inducer in vivo. The steroid hormone progesterone has been shown to evoke critical responses in sperm cells leading to the acrosome reaction. Calcium has also been shown to play a central role during the acrosome reaction. Calcium flux is induced specifically by progesterone in capacitated and uncapacitated sperm cells, whereas only capacitated spermatozoa are able to subsequently complete the acrosome reaction. Progesterone as well as zona protein has been shown to evoke crucial responses within human spermatozoa, shedding light on the cascade of intracellular signalling events leading to the completion of the acrosome reaction. Furthermore, chemical agents which bring about the reaction in vitro, such as the ionophores ionomycin or A23187, have been used to shed light on its regulatory mechanisms. A number of molecules have been postulated to regulate the acrosome reaction in mammals, for example a galactosyl-transferase and a sperm protein tyrosine kinase. In addition, a novel protein, termed SAA-1, that was first detected on human spermatozoa is discussed with respect to its potential role as a regulatory protein closely involved in the initiation of the acrosome reaction. PMID:9080206

  4. Observation of temperature trace, induced by changing of temperature inside the human body, on the human body skin using commercially available IR camera

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Trofimov, Vladislav V.

    2015-05-01

    As it is well-known, application of the passive THz camera for the security problems is very promising way. It allows seeing concealed object without contact with a person and this camera is non-dangerous for a person. In previous papers, we demonstrate new possibility of the passive THz camera using for a temperature difference observing on the human skin if this difference is caused by different temperatures inside the body. For proof of validity of our statement we make the similar physical experiment using the IR camera. We show a possibility of temperature trace on human body skin, caused by changing of temperature inside the human body due to water drinking. We use as a computer code that is available for treatment of images captured by commercially available IR camera, manufactured by Flir Corp., as well as our developed computer code for computer processing of these images. Using both codes we demonstrate clearly changing of human body skin temperature induced by water drinking. Shown phenomena are very important for the detection of forbidden samples and substances concealed inside the human body using non-destructive control without X-rays using. Early we have demonstrated such possibility using THz radiation. Carried out experiments can be used for counter-terrorism problem solving. We developed original filters for computer processing of images captured by IR cameras. Their applications for computer processing of images results in a temperature resolution enhancing of cameras.

  5. Human body impedance for electromagnetic hazard analysis in the VLF to MF band

    SciTech Connect

    Kanai, H.; Chatterjee, I.; Gandhi, O.P.

    1984-08-01

    A knowledge of the average electrical impedance of the human body is essential for the analysis of electromagnetic hazards in the VLF to MF band. The purpose of the measurements was to determine the average body impedance of several human subjects as a function of frequency. Measurements were carried out with the subjects standing barefoot on a ground plane and touching various metal electrodes with the hand or index finger. The measured impedance includes the electrode polarization and skin impedances, spread impedance near the electrode, body impedance, stray capacitance between the body surface and ground, and inductance due to the body and grounding strap. These components are separated and simplified equivalent circuits are presented for body impedance of humans exposed to free-space electromagnetic waves as well as in contact with large ungrounded metallic objects therein.

  6. The venality of human body parts and products in French law and common law.

    PubMed

    Haoulia, Naima

    2012-03-01

    The successive bioethics laws in France have constantly argued that the human body is not for sale and consecrated an absolute principle of free and anonymous donations, whether of semen, ova, blood, tissues or organs. Nonetheless, this position is not shared by all countries. These legal divergences upset today our moral principles and the development of these practices leads us to question the legal status of human biological material and its gradual commodification. This paper outlines the current law principles that protect people's interests in their bodies, excised body parts and tissues without conferring the rights of full legal ownership in French law and in Common law. Contrary to what many people believe, people do not legally 'own' their bodies, body parts or tissues. However, they do have some legal rights in relation to their bodies and excised body material. For lawyers, the exact relationship people have with their bodies has raised a host of complex questions and long debates about the status we should grant to human body parts. The significance of this issue is due to two reasons:first, because of the imperative protection we have to assure to human dignity and then, because of the economic value which is attached to human products. PMID:22530322

  7. Academic Performance in Human Anatomy and Physiology Classes: A 2-Yr Study of Academic Motivation and Grade Expectation

    ERIC Educational Resources Information Center

    Sturges, Diana; Maurer, Trent W.; Allen, Deborah; Gatch, Delena Bell; Shankar, Padmini

    2016-01-01

    This project used a nonexperimental design with a convenience sample and studied the relationship between academic motivation, grade expectation, and academic performance in 1,210 students enrolled in undergraduate human anatomy and physiology (HAP) classes over a 2-yr period. A 42-item survey that included 28 items of the adapted academic…

  8. A DYNAMIC PHYSIOLOGICALLY-BASED TOXICOKINETIC (DPBTK) MODEL FOR SIMULATION OF COMPLEX TOLUENE EXPOSURE SCENARIOS IN HUMANS

    EPA Science Inventory

    A GENERAL PHYSIOLOGICAL AND TOXICOKINETIC (GPAT) MODEL FOR SIMULATION OF COMPLEX TOLUENE EXPOSURE SCENARIOS IN HUMANS. E M Kenyon1, T Colemen2, C R Eklund1 and V A Benignus3. 1U.S. EPA, ORD, NHEERL, ETD, PKB, RTP, NC, USA; 2Biological Simulators, Inc., Jackson MS, USA, 3U.S. EP...

  9. A DXA Whole Body Composition Cross-Calibration Experience: Evaluation With Humans, Spine, and Whole Body Phantoms.

    PubMed

    Krueger, Diane; Libber, Jessie; Sanfilippo, Jennifer; Yu, Hui Jing; Horvath, Blaine; Miller, Colin G; Binkley, Neil

    2016-01-01

    New densitometer installation requires cross-calibration for accurate longitudinal assessment. When replacing a unit with the same model, the International Society for Clinical Densitometry recommends cross-calibrating by scanning phantoms 10 times on each instrument and states that spine bone mineral density (BMD) should be within 1%, whereas total body lean, fat, and %fat mass should be within 2% of the prior instrument. However, there is limited validation that these recommendations provide adequate total body cross-calibration. Here, we report a total body cross-calibration experience with phantoms and humans. Cross-calibration between an existing and new Lunar iDXA was performed using 3 encapsulated spine phantoms (GE [GE Lunar, Madison, WI], BioClinica [BioClinica Inc, Princeton, NJ], and Hologic [Hologic Inc, Bedford, MA]), 1 total body composition phantom (BioClinica), and 30 human volunteers. Thirty scans of each phantom and a total body scan of human volunteers were obtained on each instrument. All spine phantom BMD means were similar (within 1%; <-0.010 g/cm2 bias) between the existing and new dual-energy X-ray absorptiometry unit. The BioClinica body composition phantom (BBCP) BMD and bone mineral content (BMC) values were within 2% with biases of 0.005 g/cm2 and -3.4 g. However, lean and fat mass and %fat differed by 4.6%-7.7% with biases of +463 g, -496 g, and -2.8%, respectively. In vivo comparison supported BBCP data; BMD and BMC were within ∼2%, but lean and fat mass and %fat differed from 1.6% to 4.9% with biases of +833 g, -860 g, and -1.1%. As all body composition comparisons exceeded the recommended 2%, the new densitometer was recalibrated. After recalibration, in vivo bias was lower (<0.05%) for lean and fat; -23 and -5 g, respectively. Similarly, BBCP lean and fat agreement improved. In conclusion, the BBCP behaves similarly, but not identical, to human in vivo measurements for densitometer cross-calibration. Spine phantoms, despite good

  10. A PHYSIOLOGICALLY-BASED PHARMACOKINETIC MODEL FOR TOLUENE IN THE LONG EVANS RAT: BODY COMPOSITION AND PHYSICAL ACTIVITY.

    EPA Science Inventory

    A physiologically-based pharmacokinetic (PBPK) model for inhaled toluene was developed for Long-Evans rats as a component of an exposure-dose-response (EDR) model for volatile organic compounds. The PBPK model was needed to link airborne toluene exposure to its concentration in b...

  11. [Human body meridian spatial decision support system for clinical treatment and teaching of acupuncture and moxibustion].

    PubMed

    Wu, Dehua

    2016-01-01

    The spatial position and distribution of human body meridian are expressed limitedly in the decision support system (DSS) of acupuncture and moxibustion at present, which leads to the failure to give the effective quantitative analysis on the spatial range and the difficulty for the decision-maker to provide a realistic spatial decision environment. Focusing on the limit spatial expression in DSS of acupuncture and moxibustion, it was proposed that on the basis of the geographic information system, in association of DSS technology, the design idea was developed on the human body meridian spatial DSS. With the 4-layer service-oriented architecture adopted, the data center integrated development platform was taken as the system development environment. The hierarchical organization was done for the spatial data of human body meridian via the directory tree. The structured query language (SQL) server was used to achieve the unified management of spatial data and attribute data. The technologies of architecture, configuration and plug-in development model were integrated to achieve the data inquiry, buffer analysis and program evaluation of the human body meridian spatial DSS. The research results show that the human body meridian spatial DSS could reflect realistically the spatial characteristics of the spatial position and distribution of human body meridian and met the constantly changeable demand of users. It has the powerful spatial analysis function and assists with the scientific decision in clinical treatment and teaching of acupuncture and moxibustion. It is the new attempt to the informatization research of human body meridian. PMID:26946752

  12. Why the way we consider the body matters – Reflections on four bioethical perspectives on the human body

    PubMed Central

    Schicktanz, Silke

    2007-01-01

    Background Within the context of applied bioethical reasoning, various conceptions of the human body are focused upon by the author in relation to normative notions of autonomy. Results The author begins by descriptively exploring some main positions in bioethics from which the "body" is conceptualized. Such positions conflict: the body is that which is constitutive of the individual's experience and perception, or it is conceived of materially or mechanistically; or as a constructed locus, always historically and culturally transformed. The author goes on to suggest a methodological approach that dialectically considers embodiment from four different perspectives: as bodily self-determination, as respect for the bodily unavailability of the other, as care for bodily individuality; and lastly, as acknowledgement of bodily-constituted communities. These four perspectives encompass autonomy in two of its main interpretations: as the capability of a person to act independent of external forces, and as the moral ideal of pursuing individual wishes by means of role distance, self-limitation and universalization. Various bioethical cases are utilized to show how the four perspectives on the body can complement one another. Conclusion The way we consider the body matters. The author's dialectical method allows a premise-critical identification and exploration of bioethical problems concerning the body. The method is potentially applicable to other bioethical problems. PMID:18053201

  13. Diagram of Calcium Movement in the Human Body

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This diagram shows the normal pathways of calcium movement in the body and indicates changes (green arrows) seen during preliminary space flight experiments. Calcium plays a central role because 1) it gives strength and structure to bone and 2) all types of cells require it to function normally. To better understand how and why weightlessness induces bone loss, astronauts have participated in a study of calcium kinetics -- that is, the movement of calcium through the body, including absorption from food, and its role in the formation and breakdown of bone.

  14. Creating a Tiny Human Body on a Chip

    ScienceCinema

    Hunsberger, Maren; Soscia, Dave; Moya, Monica

    2016-03-16

    LLNL science communicator Maren Hunsberger takes us "Inside the Lab" to learn about the iChip (In-vitro Chip-based Human Investigational Platform) project at Lawrence Livermore National Laboratory. "One application of the iChip system would be to develop new pharmaceutical drugs," explains Dave Soscia, LLNL postdoc. "When you test in a mouse for example, it's not as close to the human system as you can get. If we can take human cells and put them on devices and actually mimic the structure and function of the organ systems in the human, we can actually replace animal testing and even make a better system for testing pharmaceutical drugs."

  15. The mathematical description of the body centre of mass 3D path in human and animal locomotion.

    PubMed

    Minetti, Alberto E; Cisotti, Caterina; Mian, Omar S

    2011-05-17

    Although the 3D trajectory of the body centre of mass during ambulation constitutes the 'locomotor signature' at different gaits and speeds for humans and other legged species, no quantitative method for its description has been proposed in the literature so far. By combining the mathematical discoveries of Jean Baptiste Joseph Fourier (1768-1830, analysis of periodic events) and of Jules Antoine Lissajous (1822-1880, parametric equation for closed loops) we designed a method simultaneously capturing the spatial and dynamical features of that 3D trajectory. The motion analysis of walking and running humans, and the re-processing of previously published data on trotting and galloping horses, as moving on a treadmill, allowed to obtain closed loops for the body centre of mass showing general and individual locomotor characteristics. The mechanical dynamics due to the different energy exchange, the asymmetry along each 3D axis, and the sagittal and lateral energy recovery, among other parameters, were evaluated for each gait according to the present methodology. The proposed mathematical description of the 3D trajectory of the body centre of mass could be used to better understand the physiology and biomechanics of normal locomotion, from monopods to octopods, and to evaluate individual deviations with respect to average values as resulting from gait pathologies and the restoration of a normal pattern after pharmacological, physiotherapeutic and surgical treatments. PMID:21463861

  16. A hyperspectral time resolved DOT system to monitor physiological changes of the human brain activity

    NASA Astrophysics Data System (ADS)

    Lange, F.; Peyrin, F.; Montcel, B.

    2015-07-01

    Diffuse optical tomography (DOT) is a growing area of research in the field of biomedical optics and neurosciences. Over the past 20 years, technical development allowed a more and more accurate detection of the brain activation, both spatially and in the calculation of the variations of chromophores's concentrations such as Hemoglobin, cytochrome c oxidase, etc. In particular, time resolved systems are able to distinguish between superficial layers (skin, skull) and deep layers (brain) allowing the differentiation between the systemic response and the response of the brain. In order to increase the accuracy of the brain's activation detection, we have developed a Hyperspectral Time Resolved DOT system. It is composed of a compact supercontinuum laser within the picosecond range for the source part and of an ICCD camera coupled with an imaging spectrometer for the detection part. This allows a simultaneous detection of the spatial and spectral dimension, as well as the time of flight of photons. Through the information acquired by our system, we've been able to retrieve, to our knowledge, the first spectrum of the physiology of the human brain activity as function as depth. Here we present the instrument and show our first in-vivo results that are demonstrating its capabilities to distinguish between the skin's response and the brain's responses during a cognitive task. We are also focused on the detection of the Fast Optical Signal.

  17. Muscarinic cholinergic receptor in the human heart evidenced under physiological conditions by positron emission tomography.

    PubMed Central

    Syrota, A; Comar, D; Paillotin, G; Davy, J M; Aumont, M C; Stulzaft, O; Maziere, B

    1985-01-01

    The muscarinic receptor was studied in vivo in the human heart by a noninvasive method, positron emission tomography (PET). The study showed that the binding sites of 11C-labeled methiodide quinuclidinyl benzilate [( 11C]-MQNB), a muscarinic antagonist, were mainly distributed in the ventricular septum (98 pmol/cm3 of heart) and in the left ventricular wall (89 pmol/cm3), while the atria were not visualized. A few minutes after a bolus intravenous injection, the concentration of [11C]MQNB in blood fell to a negligible level (less than 100th of the concentration measured in the ventricular septum). When injected at high specific radioactivity, the concentration of [11C]MQNB in the septum rapidly increased and then remained constant with time. This result was explained by rebinding of the ligand to receptors. It was the major difference observed between the kinetics of binding of [11C]MQNB to receptor sites after intravenous injection in vivo and that of [3H]MQNB to heart homogenates in vitro. The MQNB concentrations in the ventricular septum of different individuals were found to be highest when the heart rate at the time of injection was slow. This result suggests that the antagonist binding site is related to a low-affinity conformational state of the receptor under predominant vagal stimulation. Thus, positron emission tomography might be the ideal method to study the physiologically active form of the muscarinic acetylcholine receptor in man. Images PMID:3871527

  18. The effect of early experience on odor perception in humans: psychological and physiological correlates.

    PubMed

    Poncelet, Johan; Rinck, Fanny; Bourgeat, Fanny; Schaal, Benoist; Rouby, Catherine; Bensafi, Moustafa; Hummel, Thomas

    2010-04-01

    The olfactory function in humans is characterized by wide variability between individuals. One of the prominent factors that contribute to this plasticity is early exposure. The present study examined how brain activity is modulated by such olfactory experience. To this end, two groups of people living in France but originating from different cultures ("European-French" (EF, 18 subjects) vs. "Algerian-French" (AF, 19 subjects)) were tested, and their perceptual and physiological responses to the smells of mint (presumed to be experienced earlier in life by "Algerian-French" subjects) and of rose (control odorant) were compared. Neurophysiological responses were obtained in the form of chemosensory event-related potentials (CSERP). The results confirmed that the AF group was exposed to Mint tea earlier than the EF group. On the perceptual level, when asked to associate the smell of mint with objects or events retrieved from memory, the discourse of AF subjects included more "experience-oriented" associations than that of EF subjects. This was associated with longer P2 latency in CSERPs in response to the smell of mint in the AF group. These findings highlight the plasticity of behavioral and neural olfactory processes as a result of differential lifetime exposure. PMID:20035792

  19. Ultrasensitive, passive and wearable sensors for monitoring human muscle motion and physiological signals.

    PubMed

    Cai, Feng; Yi, Changrui; Liu, Shichang; Wang, Yan; Liu, Lacheng; Liu, Xiaoqing; Xu, Xuming; Wang, Li

    2016-03-15

    Flexible sensors have attracted more and more attention as a fundamental part of anthropomorphic robot research, medical diagnosis and physical health monitoring. Here, we constructed an ultrasensitive and passive flexible sensor with the advantages of low cost, lightness and wearability, electric safety and reliability. The fundamental mechanism of the sensor is based on triboelectric effect inducing electrostatic charges on the surfaces between two different materials. Just like a plate capacitor, current will be generated while the distance or size of the parallel capacitors changes caused by the small mechanical disturbance upon it and therefore the output current/voltage will be produced. Typically, the passive sensor unambiguously monitors muscle motions including hand motion from stretch-clench-stretch, mouth motion from open-bite-open, blink and respiration. Moreover, this sensor records the details of the consecutive phases in a cardiac cycle of the apex cardiogram, and identify the peaks including percussion wave, tidal wave and diastolic wave of the radial pulse wave. To record subtle human physiological signals including radial pulsilogram and apex cardiogram with excellent signal/noise ratio, stability and reproducibility, the sensor shows great potential in the applications of medical diagnosis and daily health monitoring. PMID:26520253

  20. Amyloid Formation by Human Carboxypeptidase D Transthyretin-like Domain under Physiological Conditions*

    PubMed Central

    Garcia-Pardo, Javier; Graña-Montes, Ricardo; Fernandez-Mendez, Marc; Ruyra, Angels; Roher, Nerea; Aviles, Francesc X.; Lorenzo, Julia; Ventura, Salvador

    2014-01-01

    Protein aggregation is linked to a growing list of diseases, but it is also an intrinsic property of polypeptides, because the formation of functional globular proteins comes at the expense of an inherent aggregation propensity. Certain proteins can access aggregation-prone states from native-like conformations without the need to cross the energy barrier for unfolding. This is the case of transthyretin (TTR), a homotetrameric protein whose dissociation into its monomers initiates the aggregation cascade. Domains with structural homology to TTR exist in a number of proteins, including the M14B subfamily carboxypeptidases. We show here that the monomeric transthyretin-like domain of human carboxypeptidase D aggregates under close to physiological conditions into amyloid structures, with the population of folded but aggregation-prone states being controlled by the conformational stability of the domain. We thus confirm that the TTR fold keeps a generic residual aggregation propensity upon folding, resulting from the presence of preformed amyloidogenic β-strands in the native state. These structural elements should serve for functional/structural purposes, because they have not been purged out by evolution, but at the same time they put proteins like carboxypeptidase D at risk of aggregation in biological environments and thus can potentially lead to deposition diseases. PMID:25294878

  1. Physiological modes of action of fluoxetine and its human metabolites in algae.

    PubMed

    Neuwoehner, Judith; Fenner, Kathrin; Escher, Beate I

    2009-09-01

    Fluoxetine, the active ingredient of many antidepressants, was identified as specifically toxic toward algae in a quantitative structure-activity relationship (QSAR) analysis with literature data for algae, daphnia, and fish. The goal of this study was to elucidate the mode of action in algae and to evaluate the toxicity of the major human metabolites of fluoxetine using two different algae tests. The time dependence and sensitivity of thedifferenteffectendpointsyield information on the physiological mode of action. Baseline toxicity was predicted with QSARs based on measured liposome-water partition coefficients. The ratio of predicted baseline toxicity to experimental toxicity (toxic ratio TR) gives information on the intrinsic potency (extent of specificity of effect). The metabolite p-trifluoromethylphenol was classified to act as baseline toxicant Fluoxetine (TR 60-150) and its pharmacologically active metabolite norfluoxetine (TR 10-80) exhibited specific toxicity. By comparison with reference compounds we conclude that fluoxetine and norfluoxetine have an effect on the energy budget of algal cells since the time pattern of these two compounds is most similar to that observed for norflurazon, but they act less specifically as indicated by lower TR values and the similarity of the effect pattern to baseline toxicants. The mixture toxicity of fluoxetine and its human metabolites norfluoxetine and p-TFMP can be predicted using the model of concentration addition for practical purposes of risk assessment despite small deviations from this model for the specific endpoints like PSII inhibition because the integrative endpoints like growth rate and reproduction in all cases gave agreement with the predictions for concentration addition. PMID:19764256

  2. Modulation of histamine release from human basophils in vitro by physiological concentrations of zinc

    SciTech Connect

    Marone, G.; Findlay, S.R.; Lichtenstein, L.M.

    1981-05-01

    Zinc, at physiologic concentrations, inhibits in vitro histamine release from human basophils induced by several immunologic (i.e., antigen and anti-immunoglobulin E (IgE) and nonimmunologic (Ca/sup + +/ ionophore A23187 and formylated tripeptide formyl-methionyl-leucyl-phenylalanine (f-met peptide)) stimuli in a dose-dependent manner. Inhibition begins at about 10(-6) (ionophore A23187, anti-IgE and antigen) or 10(-5) M (f-met peptide) and is maximum at 10(-4) M (80--100% inhibition of histamine release). The activity of zinc is about 25-fold greater with respect to ionophore A23187 (ID50 . 1.1 x 10(-6) M) than to f-met peptide-induced (ID50 . 4 x 10(-5) M) histamine release. Its activity on IgE-mediated histamine release is intermediate between these two extremes (ID50 . 9.7 x 10(-6) M). Zinc does not affect the first stage of histamine release but acts on the calcium-dependent second stage. It is a competitive antagonist of the action of Ca/sup + +/ in histamine secretion induced by antigen, anti-IgE and f-met peptide (but not by A23187) with a dissociation constant of about 1.2 x 10(-5) M. The addition of colchicine with zinc fails to increase the inhibition caused by the ion alone, suggesting the two compounds work via a common mechanism of action. Deuterium oxide reversed, in a dose-dependent manner, the inhibition of histamine release caused by zinc. These results suggest that the effect of zinc on histamine release from human basophils may be related to its influence on the microtubule system, directly or via its interaction with calcium.

  3. Crystal Structure of Human Senescence Marker Protein 30: Insights Linking Structural, Enzymatic, and Physiological Functions

    SciTech Connect

    Chakraborti, Subhendu; Bahnson, Brian J.

    2010-05-25

    Human senescence marker protein 30 (SMP30), which functions enzymatically as a lactonase, hydrolyzes various carbohydrate lactones. The penultimate step in vitamin-C biosynthesis is catalyzed by this enzyme in nonprimate mammals. It has also been implicated as an organophosphate hydrolase, with the ability to hydrolyze diisopropyl phosphofluoridate and other nerve agents. SMP30 was originally identified as an aging marker protein, whose expression decreased androgen independently in aging cells. SMP30 is also referred to as regucalcin and has been suggested to have functions in calcium homeostasis. The crystal structure of the human enzyme has been solved from X-ray diffraction data collected to a resolution of 1.4 {angstrom}. The protein has a 6-bladed {beta}-propeller fold, and it contains a single metal ion. Crystal structures have been solved with the metal site bound with either a Ca{sup 2+} or a Zn{sup 2+} atom. The catalytic role of the metal ion has been confirmed by mutagenesis of the metal coordinating residues. Kinetic studies using the substrate gluconolactone showed a k{sub cat} preference of divalent cations in the order Zn{sup 2+} > Mn{sup 2+} > Ca{sup 2+} > Mg{sup 2+}. Notably, the Ca{sup 2+} had a significantly higher value of K{sub d} compared to those of the other metal ions tested (566, 82, 7, and 0.6 {micro}m for Ca{sup 2+}, Mg{sup 2+}, Zn{sup 2+}, and Mn{sup 2+}, respectively), suggesting that the Ca{sup 2+}-bound form may be physiologically relevant for stressed cells with an elevated free calcium level.

  4. Human body donation programs in Sri Lanka: Buddhist perspectives.

    PubMed

    Subasinghe, Sandeepani Kanchana; Jones, D Gareth

    2015-01-01

    Considerable attention is being given to the availability of bodies for anatomical education. This raises the question of the manner in which they are obtained, that is, whether they are unclaimed or donated. With increasing emphasis upon the ethical desirability of using body bequests, the spotlight tends to be focused on those countries with factors that militate against donations. However, little attention has been paid to cultures where donations are readily available. One such country is Sri Lanka where the majority of the Buddhist population follows Theravada Buddhism. Within this context, the expectation is that donations will be given selflessly without expecting anything in return. This is because donation of one's body has blessings for a better outcome now and in the afterlife. The ceremonies to honor donors are outlined, including details of the "Pirith Ceremony." The relevance for other cultures of these features of body donation is discussed paying especial attention to the meaning of altruism and consent, and justification for the anonymization of cadavers. The degree to which anatomy is integrated into the surrounding culture also emerges as significant. PMID:25689145

  5. [Inclusion Bodies are Formed in SFTSV-infected Human Macrophages].

    PubMed

    Jin, Cong; Song, Jingdong; Han, Ying; Li, Chuan; Qiu, Peihong; Liang, Mifang

    2016-01-01

    The severe fever with thrombocytopenia syndrome virus (SFTSV) is a new member in the genus Phlebovirus of the family Bunyaviridae identified in China. The SFTSV is also the causative pathogen of an emerging infectious disease: severe fever with thrombocytopenia syndrome. Using immunofluorescent staining and confocal microscopy, the intracellular distribution of nucleocapsid protein (NP) in SFTSV-infected THP-1 cells was investigated with serial doses of SFTSV at different times after infection. Transmission electron microscopy was used to observe the ultrafine intracellular structure of SFTSV-infected THP-1 cells at different times after infection. SFTSV NP could form intracellular inclusion bodies in infected THP-1 cells. The association between NP-formed inclusion bodies and virus production was analyzed: the size of the inclusion body formed 3 days after infection was correlated with the viral load in supernatants collected 7 days after infection. These findings suggest that the inclusion bodies formed in SFTSV-infected THP-1 cells could be where the SFTSV uses host-cell proteins and intracellular organelles to produce new viral particles. PMID:27295879

  6. Carbon offers advantages as implant material in human body

    NASA Technical Reports Server (NTRS)

    Benson, J.

    1969-01-01

    Because of such characteristics as high strength and long-term biocompatability, aerospace carbonaceous materials may be used as surgical implants to correct pathological conditions in the body resulting from disease or injury. Examples of possible medical uses include bone replacement, implantation splints and circulatory bypass implants.

  7. Taking a "Giant Tour" to Explore the Human Body

    ERIC Educational Resources Information Center

    Davies, Dan

    2013-01-01

    Helping children to visualise what is inside them and how their bodies work can be a challenge, since teachers are often reliant on secondary sources or investigations that can only measure outward signs (such as pulse rate). Another way is to involve the children in an imaginative role-play exercise where they explore the insides of a…

  8. Human body surface area: measurement and prediction using three dimensional body scans.

    PubMed

    Tikuisis, P; Meunier, P; Jubenville, C E

    2001-08-01

    The development of three dimensional laser scanning technology and sophisticated graphics editing software have allowed an alternative and potentially more accurate determination of body surface area (BSA). Raw whole-body scans of 641 adults (395 men and 246 women) were obtained from the anthropometric data base of the Civilian American and European Surface Anthropometry Resource project. Following surface restoration of the scans (i.e. patching and smoothing), BSA was calculated. A representative subset of the entire sample population involving 12 men and 12 women (G24) was selected for detailed measurements of hand surface area (SAhand) and ratios of surface area to volume (SA/VOL) of various body segments. Regression equations involving wrist circumference and arm length were used to predict SAhand of the remaining population. The overall [mean (SD)] of BSA were 2.03 (0.19) and 1.73 (0.19) m2 for men and women, respectively. Various prediction equations were tested and although most predicted the measured BSA reasonably closely, residual analysis revealed an overprediction with increasing body size in most cases. Separate non-linear regressions for each sex yielded the following best-fit equations (with root mean square errors of about 1.3%): BSA (cm2) = 128.1 x m0.44 x h0.60 for men and BSA = 147.4 x m0.47 x h0.55 for women, where m, body mass, is in kilograms and h, height, is in centimetres. The SA/VOL ratios of the various body segments were higher for the women compared to the men of G24, significantly for the head plus neck (by 7%), torso (19%), upper arms (15%), forearms (20%), hands (18%), and feet (11%). The SA/VOL for both sexes ranged from approximately 12.m-1 for the pelvic region to 104-123.m-1 for the hands, and shape differences were a factor for the torso and lower leg. PMID:11560080

  9. The Knee Joint Loose Body as a Source of Viable Autologous Human Chondrocytes

    PubMed Central

    Melrose, J.

    2016-01-01

    Loose bodies are fragments of cartilage or bone present in the synovial fluid. In the present study we assessed if loose bodies could be used as a source of autologous human chondrocytes for experimental purposes. Histochemical examination of loose bodies and differential enzymatic digestions were undertaken, the isolated cells were cultured in alginate bead microspheres and immunolocalisations were undertaken for chondrogenic markers such as aggrecan, and type II collagen. Isolated loose body cells had high viability (≥90% viable), expressed chondrogenic markers (aggrecan, type II collagen) but no type I collagen. Loose bodies may be a useful source of autologous chondrocytes of high viability. PMID:27349321

  10. Revisiting the importance of common body motion in human action perception.

    PubMed

    Thurman, Steven M; Lu, Hongjing

    2016-01-01

    Human actions are complex dynamic stimuli comprised of two principle motion components: 1) common body motion, which represents the translation of the body when a person moves through space, and 2) relative limb movements, resulting from articulation of limbs after factoring out common body motion. Historically, most research in biological motion has focused primarily on relative limb movements while discounting the role of common body motion in human action perception. The current study examined the relative contribution of posture change resulting from relative limb movements and translation of body position resulting from common body motion in discriminating human walking versus running actions. We found that faster translation speeds of common body motion evoked significantly more responses consistent with running when discriminating ambiguous actions morphed between walking and running. Furthermore, this influence was systematically modulated by the uncertainty associated with intrinsic cues as determined by the degree of limited-lifetime spatial sampling. The contribution of common body motion increased monotonically as the reliability of inferring posture changes on the basis of intrinsic cues decreased. These results highlight the importance of translational body movements and their interaction with posture change as a result of relative limb movements in discriminating human actions when visual input information is sparse and noisy. PMID:26603043

  11. The evolution of body size and shape in the human career.

    PubMed

    Jungers, William L; Grabowski, Mark; Hatala, Kevin G; Richmond, Brian G

    2016-07-01

    Body size is a fundamental biological property of organisms, and documenting body size variation in hominin evolution is an important goal of palaeoanthropology. Estimating body mass appears deceptively simple but is laden with theoretical and pragmatic assumptions about best predictors and the most appropriate reference samples. Modern human training samples with known masses are arguably the 'best' for estimating size in early bipedal hominins such as the australopiths and all members of the genus Homo, but it is not clear if they are the most appropriate priors for reconstructing the size of the earliest putative hominins such as Orrorin and Ardipithecus The trajectory of body size evolution in the early part of the human career is reviewed here and found to be complex and nonlinear. Australopith body size varies enormously across both space and time. The pre-erectus early Homo fossil record from Africa is poor and dominated by relatively small-bodied individuals, implying that the emergence of the genus Homo is probably not linked to an increase in body size or unprecedented increases in size variation. Body size differences alone cannot explain the observed variation in hominin body shape, especially when examined in the context of small fossil hominins and pygmy modern humans.This article is part of the themed issue 'Major transitions in human evolution'. PMID:27298459

  12. Advances in understanding of mammalian penile evolution, human penile anatomy and human erection physiology: Clinical implications for physicians and surgeons

    PubMed Central

    Hsieh, Cheng-Hsing; Liu, Shih-Ping; Hsu, Geng-Long; Chen, Heng-Shuen; Molodysky, Eugen; Chen, Ying-Hui; Yu, Hong-Jeng

    2012-01-01

    Summary Recent studies substantiate a model of the tunica albuginea of the corpora cavernosa as a bi-layered structure with a 360° complete inner circular layer and a 300° incomplete outer longitudinal coat spanning from the bulbospongiosus and ischiocavernosus proximally and extending continuously into the distal ligament within the glans penis. The anatomical location and histology of the distal ligament invites convincing parallels with the quadrupedal os penis and therefore constitutes potential evidence of the evolutionary process. In the corpora cavernosa, a chamber design is responsible for facilitating rigid erections. For investigating its venous factors exclusively, hemodynamic studies have been performed on both fresh and defrosted human male cadavers. In each case, a rigid erection was unequivocally attainable following venous removal. This clearly has significant ramifications in relation to penile venous surgery and its role in treating impotent patients. One deep dorsal vein, 2 cavernosal veins and 2 pairs of para-arterial veins (as opposed to 1 single vein) are situated between Buck’s fascia and the tunica albuginea. These newfound insights into penile tunical, venous anatomy and erection physiology were inspired by and, in turn, enhance clinical applications routinely encountered by physicians and surgeons, such as penile morphological reconstruction, penile implantation and penile venous surgery. PMID:22739749

  13. A physiologically based pharmacokinetic (PBPK) model for methyl mercury (MeHg) in monkey and human

    SciTech Connect

    Gearhart, J.M.; Clewall, H.J. III; Shipp, A.M.

    1995-12-31

    A PBPK model for MeHg was developed which coherently describes MeHg pharmacokinetics in the adult rat, monkey and man, and predicts fetal levels of MeHg from in utero exposure. The model includes a description of enterohepatic recirculation of MeHg, conversion to inorganic mercury in tissues and intestinal flora, slowly reversible incorporation of mercury in tissues, and excretion of both organic and inorganic mercury into urine, feces, and hair. The adult submodel includes compartments representing the red blood tells (RBC), plasma, brain, liver, kidney, gut intestinal lumen, gut tissue, hair, richly and slowly perfused tissues, and placenta. The fetal submodel includes compartments representing RBC`s, plasma, brain, and remaining body mass. Two features of the model structure which are critical to prediction of the kinetics of MeHg in different species is the use of separate RBC and plasma compartments, allowing the use of species specific RBC/plasma ratios, and biliary excretion with enterohepatic recirculation. Published tissue and blood MeHg concentrations were used to derive the partition coefficients and RBC/plasma ratios to adjust for species differences in MeHg distribution. Validation involved comparing the model simulations with data from repeated dosing studies in animals and humans, and from accidental human exposures. The model will be used to investigate maternal MeHg intake as it relates to measured blood and hair MeHg concentrations, and to fetal exposure.

  14. Aggregation of Human Eyelid Adipose-derived Stem Cells by Human Body Fluids

    PubMed Central

    Song, Yeonhwa; Yun, Sujin; Yang, Hye Jin; Yoon, A Young; Kim, Haekwon

    2012-01-01

    Fetal bovine serum (FBS) is the most frequently used serum for the cultivation of mammalian cells. However, since animal-derived materials might not be appropriate due to safety issues, allogeneic human serum (HS) has been used to replace FBS, particularly for the culture of human cells. While there has been a debate about the advantages of HS, its precise effect on human adult stem cells have not been clarified. The present study aimed to investigate the effect of HS on the human eyelid adipose stem cells (HEACs) in vitro. When HEACs were cultivated in a medium containing 10% HS, many cells moved into several spots and aggregated there. The phenomenon was observed as early as 9 days following 10% HS treatment, and 12 days following 5% HS plus 5% FBS treatment. However, the aggregation was never observed when the same cells were cultivated with 10% FBS or bovine serum albumin. To examine whether cell density might affect the aggregation, cells were seeded with different densities on 12-well dish. Until the beginning of aggregation, cells seeded at low densities exhibited the longest culture period of 16 days whereas cells seeded at high densities showed the shortest period of 9 days to form aggregation. The number of cells was 15.1±0.2×104 as the least for the low density group, and 29.3±2.8×104 as the greatest for the high density group. When human cord blood serum or normal bovine serum was examined for the same effect on HEACs, interestingly, cord blood serum induced the aggregation of cells whereas bovine serum treatment has never induced. When cells were cultivated with 10% HS for 9 days, they were obtained and analyzed by RT-PCR. Compared to FBS-cultivated HEACs, HS-cultivated HEACs did not express VIM, and less expressed GATA4, PALLD. On the other hand, HS-cultivated HEACs expressed MAP2 more than FBS-cultivated HEACs. In conclusion, human adult stem cells could move and form aggregates by the treatment with human body fluids. PMID:25949109

  15. Human C-reactive protein impedes entry of leptin into the CNS and attenuates its physiological actions in the CNS.

    PubMed

    Li, Jie; Wei, Dong; McCrory, Mark A; Szalai, Alexander J; Yang, Gangyi; Li, Ling; Li, Fanghong; Zhao, Allan Z

    2016-05-01

    Defective central leptin signalling and impaired leptin entry into the CNS (central nervous system) represent two important aspects of leptin resistance in obesity. In the present study, we tested whether circulating human CRP (C-reactive protein) not only diminishes signalling of leptin within the CNS, but also impedes this adipokine's access to the CNS. Peripheral infusion of human CRP together with co-infused human leptin was associated with significantly decreased leptin content in the CSF of ob/ob mice. Furthermore, following peripheral infusion of human leptin, the CSF (cerebrospinal fluid) concentration of leptin in transgenic mice overexpressing human CRP was sharply lower than that achieved in similarly infused wild-type mice. Administration of LPS (lipopolysaccharide) to human CRP-transgenic mice dramatically elevated the concentrations of human CRP in the CSF. The i.c.v. (intracerebroventricular) delivery of human CRP into the lateral ventricles of ob/ob mice blocked the satiety and weight-reducing actions of human leptin, but not those of mouse leptin. I.c.v. injection of human CRP abolished hypothalamic signalling by human leptin, and ameliorated the effects of leptin on the expression of NPY (neuropeptide Y), AgRP (Agouti-related protein), POMC (pro-opiomelanocortin) and SOCS-3 (suppressor of cytokine signalling 3). Human CRP can impede the access of leptin to the CNS, and elevation of human CRP within the CNS can have a negative impact on the physiological actions of leptin. PMID:26933237

  16. Contact-free determination of human body segment parameters by means of videometric image processing of an anthropomorphic body model

    NASA Astrophysics Data System (ADS)

    Hatze, Herbert; Baca, Arnold

    1993-01-01

    The development of noninvasive techniques for the determination of biomechanical body segment parameters (volumes, masses, the three principal moments of inertia, the three local coordinates of the segmental mass centers, etc.) receives increasing attention from the medical sciences (e,.g., orthopaedic gait analysis), bioengineering, sport biomechanics, and the various space programs. In the present paper, a novel method is presented for determining body segment parameters rapidly and accurately. It is based on the video-image processing of four different body configurations and a finite mass-element human body model. The four video images of the subject in question are recorded against a black background, thus permitting the application of shape recognition procedures incorporating edge detection and calibration algorithms. In this way, a total of 181 object space dimensions of the subject's body segments can be reconstructed and used as anthropometric input data for the mathematical finite mass- element body model. The latter comprises 17 segments (abdomino-thoracic, head-neck, shoulders, upper arms, forearms, hands, abdomino-pelvic, thighs, lower legs, feet) and enables the user to compute all the required segment parameters for each of the 17 segments by means of the associated computer program. The hardware requirements are an IBM- compatible PC (1 MB memory) operating under MS-DOS or PC-DOS (Version 3.1 onwards) and incorporating a VGA-board with a feature connector for connecting it to a super video windows framegrabber board for which there must be available a 16-bit large slot. In addition, a VGA-monitor (50 - 70 Hz, horizontal scan rate at least 31.5 kHz), a common video camera and recorder, and a simple rectangular calibration frame are required. The advantage of the new method lies in its ease of application, its comparatively high accuracy, and in the rapid availability of the body segment parameters, which is particularly useful in clinical practice

  17. Human herpesvirus 6 and 7 are biomarkers for fatigue, which distinguish between physiological fatigue and pathological fatigue.

    PubMed

    Aoki, Ryo; Kobayashi, Nobuyuki; Suzuki, Go; Kuratsune, Hirohiko; Shimada, Kazuya; Oka, Naomi; Takahashi, Mayumi; Yamadera, Wataru; Iwashita, Masayuki; Tokuno, Shinichi; Nibuya, Masashi; Tanichi, Masaaki; Mukai, Yasuo; Mitani, Keiji; Kondo, Kazuhiro; Ito, Hiroshi; Nakayama, Kazuhiko

    2016-09-01

    Fatigue reduces productivity and is a risk factor for lifestyle diseases and mental disorders. Everyone experiences physiological fatigue and recovers with rest. Pathological fatigue, however, greatly reduces quality of life and requires therapeutic interventions. It is therefore necessary to distinguish between the two