8,987 research outputs found
Low-Cost Experimental System for Center of Mass and Center of Pressure Measurement
Falls happen when the center of mass of body is outside of its base of support and the recovery of the center of mass back to the base of support failed. Balance ability is an essential ability needed for humans\u27 daily routine activities. Improving balance ability should result in a better and more convenient way of living. There are various factors influence on balance ability. The focus of this paper is to investigate which factors have the greatest effect on balance. Balance ability is measured by deviations of center of pressure in both x-direction (side-to-side) and y-direction (front-to-back) with the age, height, body mass index, and location of body center of mass. Coordinates of subject\u27s joints were tracked and recorded by a motion capture system with three cameras and then were used to calculate the coordinates of segment\u27s mass center. The coordinates of whole body mass center were determined using the weighted segmental method. The trajectories of the center of pressure were tracked and recorded by a Wii balance board under five standing postures and slow sway movement along x-direction (side-to-side) situations. The information obtained from the center of mass and the center of pressure data analysis may assist with fall prediction and prevention. With a basic training on system operation, laypersons may use this affordable low cost system at home as an exercise tool to improve balance capability and reduce fall risk factors
Cardiac Response to Chronic Intermittent Hypoxia with a Transition from Adaptation to Maladaptation: The Role of Hydrogen Peroxide
Obstructive sleep apnea (OSA) is a highly prevalent respiratory disorder of sleep, and associated with chronic intermittent hypoxia (CIH). Experimental evidence indicates that CIH is a unique physiological state with potentially “adaptive” and “maladaptive” consequences for cardio-respiratory homeostasis. CIH is also a critical element accounting for most of cardiovascular complications of OSA. Cardiac response to CIH is time-dependent, showing a transition from cardiac compensative (such as hypertrophy) to decompensating changes (such as failure). CIH-provoked mild and transient oxidative stress can induce adaptation, but severe and persistent oxidative stress may provoke maladaptation. Hydrogen peroxide as one of major reactive oxygen species plays an important role in the transition of adaptive to maladaptive response to OSA-associated CIH. This may account for the fact that although oxidative stress has been recognized as a driver of cardiac disease progression, clinical interventions with antioxidants have had little or no impact on heart disease and progression. Here we focus on the role of hydrogen peroxide in CIH and OSA, trying to outline the potential of antioxidative therapy in preventing CIH-induced cardiac damage
Bis[2-(2-furyl)-1-(2-furylmethyl)-1H-benzimidazole-κN 3]diiodidocadmium
In the title complex, [CdI2(C16H12N2O2)2], the CdII atom is located on a twofold rotation axis and is four-coordinated by two N atoms from symmetry-related 2-(2-furyl)-1-(2-furylmethyl)-1H-benzimidazole ligands and two I atoms in a distorted tetrahedral configuration. The benzimidazole rings in adjacent molecules are parallel, with an average interplanar distance of 3.486 Å. The I atom is disordered over two sites in a 0.85 (5):0.15 (5) ratio
Carbon monoxide in an extremely metal-poor galaxy
Extremely metal-poor galaxies with metallicity below 10% of the solar value
in the local universe are the best analogues to investigating the interstellar
medium at a quasi-primitive environment in the early universe. In spite of the
ongoing formation of stars in these galaxies, the presence of molecular gas
(which is known to provide the material reservoir for star formation in
galaxies, such as our Milky Way) remains unclear. Here, we report the detection
of carbon monoxide (CO), the primary tracer of molecular gas, in a galaxy with
7% solar metallicity, with additional detections in two galaxies at higher
metallicities. Such detections offer direct evidence for the existence of
molecular gas in these galaxies that contain few metals. Using archived
infrared data, it is shown that the molecular gas mass per CO luminosity at
extremely low metallicity is approximately one-thousand times the Milky Way
value.Comment: 12 pages, 3 figures, 1 table. Supplementary data at
http://www.nature.com/article-assets/npg/ncomms/2016/161209/ncomms13789/extref/ncomms13789-s1.pd
DND1 Expression and Function in the Porcine Ovary, Oocyte and Embryo
DND1 (dead end homolog 1), belonging to the RNA binding protein family, can impact miRNA:mRNA functional pathway and in turn may contribute to maintaining normal oocyte growth and quality as well as embryo development following fertilization. To characterize DND1 in pig maturing oocytes and cumulus cells, and early embryos, we examined DND1 mRNA and protein expression using quantitative RT-PCR, Western blot and immunostaining. We found: (1) DND1 protein is expressed during pig follicle development; (2) DND1 is dynamically expressed at both mRNA and protein level in the maturing oocyte and early in vitro fertilized embryos; (3) DND1 mRNA is expressed in cumulus cells surrounding the maturing oocyte; and (4) DND1 protein is localized in the cytoplasm of pig maturing oocytes and early embryos. Our work provides useful data for functional study of DND1 proteins in female gametogenesis and developing embryos, which will benefit animal reproduction health and provides foundational knowledge for improving swine reproductive efficiency
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