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Association of Body Composition and Aerobic Fitness on Heart Rate Variability and Recovery in Young-Adult Black Men

International j.urnal of Clinical Medicine 2013年第12期4卷 532-538页

作者： Michael R. Esco Robert L. Herron stephen j. carter Andrew A. Flatt Exercise Physiology Laboratory Department of Kinesiology The University of Alabama Tuscaloosa USA Human Performance Laboratory Department of Physical Education and Exercise Science Auburn University at Montgomery Montgomery USA

Background: The primary purpose of this investigation was to determine the differences in resting heart rate variability and heart rate recovery between norm-referenced aerobic fitness groupings, independent of body composition, in Black men. Additionally, we sought to clarify the independent relationships that heart rate variability and heart rate recovery displayed with maximal aerobic fitness and selected body composition measures. Methods: Body mass index, waist circumference, and the sum of skinfold thickness were determined in forty Black men (23 ± 3 years). Each subj.ct assumed a supine position while heart rate variability was analyzed for 5-minute and recorded as normalized high-frequency power and normalized low-frequency power to normalized high frequency ratio. A graded exercise treadmill protocol was performed to attain maximal aerobic fitness. Heart rate recovery was recorded at 1- and 2-minute of a cool-down period. Heart rate variability and heart rate recovery were compared across two groups whose maximal aerobic fitness was either below or above the normative mean value for the age group of men. Results: The results indicated that heart rate variability was higher in the group whose maximal aerobic fitness was above the normative mean value compared with the lower fit group (p j.sting for body composition (p > 0.05). Regression analysis revealed that the sum of skinfolds accounted for the variation in normalized high frequency power (R2 = 0.20, p < 0.05) and normalized low-frequency power to normalized high frequency ratio (R2 = 0.30, p < 0.05), while waist circumference accounted for the variation in heart rate recovery at 2-minute (R2 = 0.20, p Conclusion: The results suggest that heart rate variability and heart rate recovery hold independent relationships to body composition but not aerobic fitness in young-adult, Black men.

关键词： Skinfold Thickness Waist Circumference Cardiovascular Autonomic

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Combining Aluminum Heat Treat with Hot Isostatic Pressing: A Comparison of Structure, Properties, and Processing Routes for a Cast AI-Si-Mg Alloy

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材料热处理学报 2004年第5期25卷 546-551页

作者： stephen j. Mashl Body cote HIP Inc. Andover Massachusetts USA

Bodycote researchers have successfully demonstrated that a T6 heat treatment can be integrated with Densal?, a proprietary, aluminum specific, hot isostatic pressing (HIP) process. In this combined operation, at least a portion of the solution heat treatment is conducted at elevated pressure. During development, two issues, adiabatic cooling during depressurization and a possible variation in the kinetics of homogenization resulting from conducting the solution heat treat at elevated pressure were perceived as factors which could alter the heat treat response from that seen in conventional processing. This paper reviews the results of experiments performed to Al-Si-Mg (A356.0) castings subj.cted to both combined and conventional processing routes. Results indicate that the combined HIP and heat treat process is an efficient means of achieving a microstructure characteristic of a conventionally T6 processed material while eliminating porosity within the casting. Further, the fatigue life of an A356.0 casting processed using the combined cycle can be improved by more than an order of magnitude over the as-cast and T6 treated component.

关键词： Al-Si-Mg合金热处理热等静压缩 HIP 机械性质疲劳寿命

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Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA j.mes L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain inj.ry(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

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Differential introgression suggests candidate beneficial and barrier loci between two parapatric subspecies of Pearson＇s horseshoe bat Rhinolophus pearsoni

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Current Zoology 2016年第4期62卷 405-412页

作者： Xiuguang MAO Shuyi ZHANG stephen j. ROSSlTER Institute of Estuarine and Coastal Research East China Normal University Shanghai 200062 China School of Biological and Chemical Sciences Queen Mary University of London London E14NS UK

Observations that rates of introgression between taxa can vary across loci are increasingly common. Here, we test for differential locus-wise introgression in 2 parapatric subspecies of Pearson＇s horseshoe bat （Rhinolophus pearsoni chinensis and R. p. pearsoni）. To efficiently identify putative speciation genes and/or beneficial genes in our current system, we used a candidate gene approach by including loci from X chromosome that are suggested to be more likely involved in reproductive isolation in other organisms and loci underlying hearing that have been suggested to spread across the hybrid zone in another congeneric species. Phylogenetic and coalescent analyses were performed at 2 X-linked, 4 hearing genes, as well as 2 other autosomal loci individually. Likelihood ratio tests could not rej.ct the model of zero gene flow at 2 X-linked and 2 autosomal genes. In contrast, gene flow was supported at 3 of 4 hearing genes. While this introgression could be adaptive, we cannot rule out stochastic processes. Our results highlight the utility of the candidate gene approach in searching for speciation genes and/or beneficial genes across the species boundary in natural populations.

关键词： gene flow hybridization hybrid zone reproductive isolation.

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Time series analysis of mantle cycles Part Ⅰ:Periodicities and correlations among seven global isotopic databases

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Geoscience Frontiers 2019年第4期10卷 1305-1326页

作者： stephen j. Puetz Kent C. Condie Progressive Science Institute HonoluluHI96815USA New Mexico Institute of Mining and Technology SocorroNM87801USA

In this study,seven isotopic databases are presented and analyzed to identify mantle and crustal episodes on a global scale by focusing on periodicity ranging from 70 to 200 million years(Myr).The databases are the largest,or among the largest,compiled for each type of data-with an obj.ctive of finding some samples from every region of every continent,to make each database as global as conceivably *** databases contain zircon Lu/Hf isotopic data,whole-rock Sm/Nd isotopic data,U/Pb detrital zircon ages,U/Pb igneous zircon ages,U/Pb non-zircon ages,whole-rock Re/Os isotopic data,and large igneous province *** I of this study focuses on the periodicities of age histograms and geochemical averages developed from the seven databases,via spectral and cross-correlation *** physical cycles often propagate in exact integer multiples of a fundamental cycle,referred to as *** tests show that harmonic geological cycles of^93.5 and^187 Myr have persisted throughout terrestrial history,and the cyclicities are statistically significant for U/Pb igneous zircon ages,U/Pb detrital zircon ages,U/Pb zircon-rim ages,large igneous province ages,meanεHf(t)for all samples,meanεHf(t)values for igneous-only samples,and relative abundance of mafic *** important,cross-correlation analyses show these seven time-series are nearly synchronous(±7 Myr)with a model consisting of periodicities of 93.5 and 187 ***,the similarities between peaks in the 93.5 and 187 Myr mantle cycles and terminal ages of established and suspected superchrons provide a framework for predicting and testing superchron periodicity.

关键词： Zircon Database Isotope Statistical analysis Spectral analysis Cross correlation

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Feruloylated Arabinoxylans Are Oxidatively Cross- Linked by Extracellular Maize Peroxidase but Not by Horseradish Peroxidase

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Molecular Plant 2009年第5期2卷 883-892页

作者： Sally j. Burr stephen C. Fry The Edinburgh Cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences The University of Edinburgh Daniel Rutherford Building The King's Buildings Edinburgh EH9 3JH UK Present address: Ecologie Microbienne/UMR CNRS 5557 USC INRA 1193 Universite Claude Bernard--Lyon 1 Batiment Gregor Mendel 16 rue Dubois F-69622 Villeurbanne Cedex France

Covalent cross-linking of soluble extracellular arabinoxylans in living maize cultures, which models the cross- linking of wall-bound arabinoxylans, is due to oxidation of feruloyl esters to oligoferuloyl esters and ethers. The oxidizing system responsible could be H2O2/peroxidase, O2/laccase, or reactive oxygen species acting non-enzymically, To distinguish these possibilities, we studied arabinoxylan cross-linking in vivo and in vitro. In living cultures, exogenous, soluble, extracellular, feruloylated [pentosyl-3H]arabinoxylans underwent cross-linking, beginning abruptly 8 d after sub-culture. Crosslinking was suppressed by iodide, an H2O2 scavenger, indicating dependence on endogenous H2O2. However, exogenous H2O2 did not cause precocious cross-linking, despite the constant presence of endogenous peroxidases, suggesting that younger cultures contained natural cross-linking inhibitors. Dialysed culture-filtrates cross-linked [^3H]arabinoxylans in vitro only if H2O2 was also added, indicating a peroxidase requirement. This cross-linking was highly ionic-strength-dependent. The peroxidases responsible were heat-labile, although relatively heat-stable peroxidases （assayed on o-dianisidine） were also present. Surprisingly, added horseradish peroxidase, even after heat-denaturation, blocked the arabinoxylancross-linking action of maize peroxidases, suggesting that the horseradish protein was a competing substrate for [^3H]arabinoxylan coupling. In conclusion, we show for the first time that cross-linking of extracellular arabinoxylan in living maize cultures is an action of apoplastic peroxidases, some of whose unusual properties we report.

关键词： Cell wall cross-links phenolics ferulate peroxidase soluble extracellular polysaccharides Zea mays L.

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Time series analysis of mantle cycles Part Ⅱ:The geologic record in zircons, large igneous provinces and mantle lithosphere

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Geoscience Frontiers 2019年第4期10卷 1327-1336页

作者： Kent C. Condie stephen j. Puetz Department of Earth & Environmental Science New Mexico Institute of Mining and TechnologySocorroNM87801USA Progressive Science Institute HonoluluHI96815USA

Igneous and detrital zircons have six maj.r U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distributions and a subpeak age range per age peak≤100 *** are eight maj.r LIP age peaks(found on≥10 crustal provinces)of which only four are in common to maj.r detrital zircon age peaks(2715 Ma,1875 Ma,825 Ma,90 Ma).Of the whole-rock Re depletion ages,58%have correspo nding detrital zircon age peaks and 55%have corresponding LIP age *** age pea ks are fou nd in common to igneous zircon,detrital zircon,LIP,and Re depletion age time series(3225 Ma,2875 Ma,2145 Ma,2085 Ma,1985 Ma,1785 Ma,1455 Ma,1175 Ma,825 Ma,and 90 Ma).and these are very robust peaks on a global scale as recorded in both crustal and mantle *** 50%of the age peaks in each of these time series correspond to predicted peaks in a 94-Myr mantle cycle,including four of the ten peaks in common to all four time series(2875 Ma,1785 Ma,825 Ma and 90 Ma).Age peak widths and subpeak ranges per age peak suggest that mantle events responsible for age peaks are2500 Ma),with the number of new provinces in which age peaks are represented decreasing with time within each *** breaks between the populations(at 2.5 Ga and 1 Ga)fall near the onsets of two transitions in Earth *** First Transition may represent a change from stagnant-lid tectonics into plate tectonics and the Second Transition,the onset of subduction of continental *** maj.r factor controlling geographic distribution of age peaks is the changing locations of ***^2 Ga,age subpeaks and peaks are housed in orogens within or around the edges of crustal provinces,mostly in accretionary *** beginning at 1.9 Ga,collisional orogens become more *** coincidence in duration

关键词： Isotopic age peaks U/Pb zircon ages Re depletion ages Large igneous provinces Age peak correlation Mantle cycles

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Ontogenetic shift in response to prey-derived chemical cues in prairie rattlesnakes Crotalus viridis viridis

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Current Zoology 2012年第4期58卷 549-555页

作者： Anthony j. SAVIOLA David CHISZAR stephen E MACKESSY School of Biological Sciences University of Northern Colorado 501 20th Street CB 92 Greeley CO 80639 USA Department of Psychology CB 345 University of Colorado Boulder Colorado 80309 USA

Snakes often have specialized diets that undergo a shift from one prey type to another depending on the life stage of the snake. Crotalus viridis viridis （prairie rattlesnake） takes different prey at different life stages, and neonates typically prey on ectotherms, while adults feed almost entirely on small endotherms. We hypothesized that elevated rates of tongue flicking to chemical stimuli should correlate with particular prey consumed, and that this response shifts from one prey type to another as in- dividuals age. To examine if an ontogenetic shift in response to chemical cues occurred, we recorded the rate of tongue flicking for 25 neonate, 20 subadult, and 20 adult （average SVL = 280.9, 552, 789.5 mm, respectively） wild-caught C. v. viridis to chemi- cal stimuli presented on a cotton-tipped applicator; water-soluble cues from two ectotherms （prairie lizard, Sceloporus undulatus, and house gecko, Hemidactylusfrenatus）, two endotherms （deer mouse, Peromyscus maniculatus and lab mouse, Mus musculus）, and water controls were used. Neonates tongue flicked significantly more to chemical cues of their common prey, S. undulatus, than to all other chemical cues; however, the response to this lizard＇s chemical cues decreased in adult rattlesnakes. Subadults tongue flicked with a higher rate of tongue flicking to both S. undulatus and P. maniculatus than to all other treatments, and adults tongue flicked significantly more to P. maniculatus than to all other chemical cues. In addition, all three sub-classes demonstrated a greater response for natural prey chemical cues over chemical stimuli of prey not encountered in the wild （M. musculus and H. frenatus）. This shift in chemosensory response correlated with the previously described ontogenetic shifts in C. v. viridis diet. Be-cause many vipers show a similar ontogenetic shift in diet and venom composition, we suggest that this shift in prey cue dis- crimination is likely a general phenomenon among viperid snakes.

关键词： Gape-limited predator Prey choice Trophic adaptation Vomeronasal chemoreception

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Isolated intestinal neurofibromatous proliferations in the absence of associated systemic syndromes

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World j.urnal of Gastroenterology 2008年第42期14卷 6569-6571页

作者： j.Elliot carter j.vier A Laurini Department of Pathology University of South Alabama Alabama 36617-2293 United StatesAuthor contributions: Carter JE and Laurini JA contributed equally to this work and Carter JE and Laurini JA wrote the paper.

Gastrointestinal tract involvement by neurofibromatous lesions is rare and occurs most frequently as one of the systemic manifestations of generalized neurofibromatosis type 1 （NF1）. In this setting, the lesions may manifest as focal scattered neurofibromas or as an extensive diffuse neural hyperplasia designated ganglioneuromatosis. Occasionally, such lesions may be the initial sign of NF1 in patients without any other clinical manifestations of the disease. Rarely, cases of isolated neurofibromatosis of the large bowel with no prior or subsequent evidence of generalized neurofibromatosis have been documented. We present the case of a 52 year-old female with abdominal pain and alternating bowel habits. Colonoscopic evaluation revealed multiple small polyps in the cecum and the presence of nodular mucosa in the colon and rectum. Pathologic evaluation of the biopsies from the cecum, descending colon, sigmoid colon, and rectum revealed tangled fascicles of spindle cells expanding the lamina propia leading to separation of the intestinal crypts. Immunohistochemical stains helped confirm the diagnosis of diffuse intestinal neurofibromatosis. A thorough clinical evaluation failed to reveal any stigmata of generalized neurofibromatosis. This case represents a rare presentation of isolated intestinal neurofibromatosis in a patient without classic systemic manifestations of generalized neurofibromatosis and highlights the need in such cases for close clinical follow-up to exclude neurofibromatosis type I or multiple endocrine neoplasia type Ⅱ.

关键词： Neurofibromatous Proliferations Isolated Intestinal

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Safety and predictors of adherence of a new rehabilitation program for older women with congestive heart failure

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j.urnal of Geriatric Cardiology 2012年第3期9卷 243-246页

作者： Nahid A. Azad Kathy Bouchard Alain Mayhew Maureen carter Frank j. Molnar Geriatric Assessment Unit Ottawa Hospital Civic Campus 1053 Carling Avenue Ottawa Ontario K1Y4E9 Canada Cochrane Effective Practice and Organisation of Care Group Ottawa Hospital Civic Campus 1053 Carling Avenue Ottawa Ontario K1Y4E9 Canada j.T Programme Ottawa Hospital Civic Campus 1053 Carling Avenue Ottawa Ontario K1Y4E9 Canada The IElisabeth-Bruybre Research Institute 43 Bruybre St. Ottawa Ontario KIN 5C8 Canada

Obj.ctives To assess the safety of a cardiac rehabilitation program for older women with Congestive Heart Failure （CHF） and determine if certain factors influence adherence. Methods Women over the age of 65 with CHF attended an exercise program supervised by a physiotherapist. Quality of life was measured by the Minnesota Living with Heart Failure Questionnaire （MLHFQ） and severity of disease by the New York Heart Association （NYHA） Class. Subj.cts were classified into those who attended 90% or more of the sessions and those who attended less than 90% of the sessions. Results Fifty-one subj.cts were studied. Eight subj.cts did not attend any sessions. Of the 43 attendees, the average percentage of sessions attended was 87%. There were no significant differences between the two groups in age, MLHFQ or NYHA Class. There was only one adverse event out of 280 participant attendances. Conclusions The program had a high level of adherence in this population. Age, MLHFQ or NYHA Class did not impact on session attendance. Our data suggests this program is safe for this population. Further research is needed to determine other predictors of attendance and the examination of safety issues and long-term adherence to exercise in this population.

关键词： Congestive heart failure Exercise Elderly women Adherence

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