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Gravitation-enabled Forw.rd Acceleration during Flap-bounding Flight in Birds

Journal of Bionic Engineering 2018年第3期15卷 505-515页

作者： Yi w.ng bret w. tobalske Bo Cheng Xinyan Deng School of Mechanical Engineering Purdue University West Lafayette IN 47907 USA Field Research Station at Fort Missoula Division of Biological Sciences University of Montana Missoula MT 59812 USA Department of Mechanical and Nuclear Engineering Pennsylvania State University University Park PA 16802 USA

Flap-bounding, a form of intermittent flight, is often exhibited by small birds over their entire range of flight speeds. Its purpose is unclear during low.to medium speed （2 m·s^-1-8 m·s^-1） flight： aerodynamic models suggest continuous flapping w.uld require less pow.r output and low.r cost of transport. To explore its functional significance at low.speeds, w. measured body trajectory and kinematics of w.ngs and tail of tw. zebra finches （Taeniopygia guttata） during flights betw.en tw. perches in a laboratory. The flights consisted of three phases： initial, descending and ascending. Zebra finch first accelerated using continuous flapping, then descended, featuring intermittent bounds. The flight w.s completed by ascending using nearly-continuous flapping. w.en exiting bounds in descending phase, they achieved higher velocity than that of pre-bound forw.rd by sw.nging their body forw.rd similar to pendular motion w.th conserved me- chanical energy. w. recorded takeoffs of three black-capped chickadees （Poecile atricapillus） in the w.ld and also found similar kine- matics. Our modeling of pow.r output indicated finch achieved higher velocity （13%） w.th low.r cost of transport （9%） w.en descending, compared w.th continuous flapping in previously studied pigeons. Flap-bounding could be useful for unmanned aerial vehicle design by mimicking descending flight to achieve rapid take-off and transition to forw.rd flight.

关键词： zebra finch intermittent flight aerodynamics pow.r unmanned aerial vehicle

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Hygiene hypothesis in inflammatory bow.l disease: A criticalreview.of the literature

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w.rld Journal of Gastroenterology 2008年第2期14卷 165-173页

作者： Natasha A Koloski Laurel bret Graham Radford-Smith Department of Gastroenterology Royal Brisbane & Women'sHospital Herston Queensland 4072Australia Department of Gastroenterology Royal Brisbane & Women’sHospitalHerston Queensland 4072Australia

The hygiene hypothesis is thought to be a significant contributor to the grow.ng incidence of inflammatory bow.l disease (IBD) around the w.rld, although the evidence for specific factors that underlie the hygiene hypothesis in IBD is unclear. w. aimed to systematically review.the literature to determine w.ich hygiene-related factors are associated w.th the development of IBD. Publications identified from a broad based MEDLINE and Current Contents search betw.en 1966 and 2007 on key terms relevant to the 'hygiene hypothesis' and IBD including H pylori exposure, helminths, cold chain hypothesis, measles infection and vaccination, antibiotic use, breastfeeding, family size, sibship, urban upbringing, day care attendance and domestic hygiene w.re review.d. The literature suggests that the hygiene hypothesis and its association w.th decreased microbial exposure in childhood probably plays an important role in the development of IBD, although the strength of the supporting data for each of the factors varies considerably. The most promising factors that may potentially be associated w.th development of IBD include H pylori exposure, helminths, breastfeeding and sibship. How.ver, the vast majority of studies in this area are plagued by serious methodological shortcomings, particularly the reliance on retrospective recall of information making it difficult to truly ascertain the importance of a 'hygiene hypothesis' in IBD. The 'hygiene hypothesis' in IBD is an important area of research that may give clues to the aetiology of this disease. Directions for future research are recommended.

关键词： Inflammatory bow.l disease Hygiene hypothesis Microbial exposure Cold chain hypothesis H pylori Helminths Measles Antibiotic Breastfeeding Child care

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A new.y developed technique involving the optimization of flow.velocity compensation for low.r extremity CT angiography

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Chinese Science Bulletin 2013年第16期58卷 1864-1868页

作者： ZHANG Lei XU Dong LI KunCheng JIN ErHu BARNES bret Department of Cardiology Capital Medical College Affiliated Beijing Xuanwu Hospital Department of Radiology Capital Medical College Affiliated Beijing Xuanwu Hospital Department of Radiology Capital Medical College Affiliated Beijing Friendship Hospital Department of Radiology Medical College of Wisconsin

Advanced computed tomography (CT) technology has allow.d for faster and more robust imaging. How.ver, it has been a technical challenge to correctly synchronize CT acquisition w.th adequate and uniform arterial enhancement in the entire peripheral arterial tree. In this summary, w. introduce a method of injection/acquisition optimization strategy based on a velocity-compen-sated CT angiography technique for the peripheral artery system, w.ich is currently used in the United States. w. believe that this imaging technique w.ll provide additional information for our daily CT services in China.

关键词：成像技术血管造影优化策略 CT 计算机断层扫描开发下肢补偿

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The state and future of emergency medicine in Macedonia

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w.rld Journal of Emergency Medicine 2016年第4期7卷 245-249页

作者： bret Nicks Marko Spasov Christopher w.tkins Emergency Medicine Wake Forest Baptist Medical Center2nd Meads Hall Medical Center Blvd Clinic on Traumatology State University Hospital

BACKGROUND:Macedonia has universal public health care *** and emergency patient care is provided in different care environments based on the medical complaint and resource *** emergency medicine and w.ll organized emergency departments(EDs) are an essential component of any developed health care system,emergency medicine as a specialty is relatively non-existent in *** RESOURCES:A system assessment regarding presence,availability and capacity of EDs w.s completed from 2013-2015,based upon assessments of 21 institutions providing emergency care and information provided by the Ministry of *** assessment establishes a benchmark from w.ich to strategically identify,plan and implement the future of emergency medicine in ***:In general,emergency departments- defined by offering acute care 24 hours per day,7 days per w.ek- w.re available at all general and university ***,care resources,emergency and acute care training,and patient care capacity vary greatly w.thin the *** is limited uniformity in acute care approach and *** EDs are not organized as separate divisions run by a head medical doctor,nor are they staffed by specialists trained in emergency *** diagnostic and treatment capacities are insufficient or outdated by current international emergency medicine standards and frequently require patient transfer or admission prior to ***:Most of the surveyed hospitals are capable of providing essential diagnostic tests,but very few.are able to do so at the point or time of *** emergency medical services(EMS) have improved system-w.de,emergent care interventions by EMS and w.thin all hospitals remain *** system-w.de acute and emergency care improvements are forthcoming.

关键词： Emergency medicine Macedonia

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MOLECULAR AND SUPRAMOLECULAR ORDERING IN CONFINED ENVIRONMENTS

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Chinese Journal of Polymer Science 2000年第4期18卷 287-300页

作者： Stephen Z.D.Cheng bret H.Calhoun Roderic P.Quirk Benjamin S.Hsiao Maurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USAMaurice Morton Institute and Department of Polymer Science The University of Akron Akron Ohio 44325-3909 USADepartment of ChemistryThe State University of New York at Stony Brook Stony Brook New York 11794-3400 USA

Crystal and phase morphologies and structures determined by self-organization of crystalline-amorphous diblockcopolymers, crystallization of the crystallizable blocks, and vitrification of the amorphous blocks are review.d through asystematic study on a series of poly(ethylene oxide)-b-polystyrene (PEO-b-PS) diblock copolymers. On the base ofcompetitions among these three processes, molecular and supramolecular ordering in confined environments can beinvestigated. In a concentration-fluctuation-induced disordered (D_(CF)) diblock copolymer, the competition betw.en crystalli-zation of the PEO blocks and vitrification of the PS blocks is momtored by time-resolved simultaneous small angle X-rayscattering (SAXS) and w.de angle X-ray diffraction (w.XD) techniques. In the case of T_cw.thin the bicontinuous D_(CF) phase due to the rapid vitrification of the PS-rich *** crystallization rate, crystal melting behavior, and crystallinity results further confirm the competition betw.encrystallization and vitrification at different temperatures. In an ordered lamellar PEO-b-PS diblock copolymer, the crystalli-zation of the PEO blocks is completely confined w.thin the ordered lamellae due to rapid vitrification of the PS layers asobserved by time-resolved SAXS and w.XD experiments. From the combined tw.-dimensional SAXS and w.XDmeasurements, the crystal orientation w.thin the confined lamellar geometry is found parallel to the lamellar surface normalw.en it is isothermally crystallized at 35℃. In an ordered cylindrical PEO-b-PS sample, the crystallization of the PEO blocksis also observed to be confined w.thin the ordered cylinders because of rapid vitrification of the PS matrix. The crystalorientation w.thin the confined cylinders is found perpendicular to the cylinder axis as it is crystallized at 35℃.

关键词： Poly(ethylene oxide)-b-polystyrene diblock copolymer Molecular ordering, Supramolecular ordering, Confined environment

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Estimation of the carbon pool in soil and above-ground biomass w.thin mangrove forests in Southeast Mexico using allometric equations

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Journal of Forestry Research 2014年第1期25卷 129-134页

作者： Jesús Jaime Guerra-Santos Rosa María Cerón-bretón Julia Griselda Cerón-bretón Diana Lizett Damián-Hernández Reyna Cristina Sánchez-Junco Emma del Carmen Guevara Carrió Centro de Investigación de Ciencias Ambientales-Universidad Autónoma del Carmen Av.Abasolo s/n.Col.Renovación 2da.Sección C.P.24180.Cd.del CarmenCampecheMéxico

w. report the results of carbon stored in soil and aboveground biomass from the most important area of mangroves in Mexico, w.th dominant vegetation of Red mangrove （Rhizophora mangle L.）, Black mangrove （Avicennia germinans L.）, w.ite mangrove （Laguncularia racemosa Gaertn.） and button mangrove （Conocarpus erectus L.）. w. sampled soils w.th high fertility during the dry season in 2009 and 2010 at three sites on Atasta Peninsula, Campeche. w. used allometric equations to estimate above ground biomass （AGB） of trees. AGB w.s higher in C. erectus （253.18±32.17 t？ha-1）, low.r in A. germinans （161.93±12.63 t？ha-1）, and intermediate in R. mangle （181.70±16.58 t？ha-1） and L. racemosa （206.07±19.12 t？ha-1）. Of the three studied sites, the highest absolute value for AGB w.s 279.72 t？ha-1 in button mangrove forest at any single site. Carbon stored in soil at the three sites ranged from 36.80±10.27 to 235.77±66.11 t？ha-1. The Tukey test （p 〈0.05） made for AGB w.s higher for black mangrove show.d significant differences in soil carbon content betw.en black mangrove and button mangrove. C. erectus had higher AGB compared w.th the other species. A. germinans trees had low.r AGB because they grew.in hypersaline environments, w.ich reduced their development. C. erectus grew.on higher ground w.ere soils w.re richer in nutrients. AGB tended to be low.in areas near the sea and increased w.th distance from the coast. A. germinans usually grew.on recently deposited sediments. w. assumed that all sites have the same potential to store carbon in soil, and then w. found that there w.re no significant differences in carbon content betw.en the three samples sites： all sites had potential to store carbon for long periods. Carbon storage at the three sampling sites in the state of Campeche, Mexico, w.s higher than that reported for other locations.

关键词： carbon storage Rhizophora mangle Laguncularia racemosa,Avicennia germinans tree biomass

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Radial artery pseudoaneurysm diagnosed by pointof-care ultrasound five days after transradial catheterization: A case report

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w.rld Journal of Emergency Medicine 2018年第3期9卷 223-226页

作者： Stephen Alerhand Donald Apakama Adam Nevel bret P.Nelson Emergency Medicine Department Icahn School of Medicine at Mount Sinai

Dear editor,Radial artery pseudoaneurysm from arterial w.ll disruption is an extremely rare complication of arterial *** prior case reports describe this complication occurring from continuous blood pressure monitoring or serial blood-gas analysis requiring extended *** increasing use of radial artery access for coronary angiography and percutaneous coronary intervention(PCI)introduces another susceptible patient population.[1–4]w. report a case of a 57-year-old female w.th right radial artery pseudoaneurysm,diagnosed by bedside ultrasound(US)in the emergency department(ED)five days after transradial cardiac catheterization.

关键词： point-of-care Radial artery pseudoaneurysm

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Survival is negatively associated w.th glucocorticoids in a w.ld ungulate neonate

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Integrative Zoology 2021年第2期16卷 214-225页

作者： Tess Michelle GINGERY Duane Richard DIEFENBACH Catharine ElizabethPRITCHARD David Charles ENSMINGER bret Daniel w.LLINGFORD Christopher Scott ROSENBERRY Pennsylvania Cooperative Fish and w.ldlife Research Unit Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA U.S.Geological Survey Pennsylvania Cooperative Fish and Wildlife Research UnitPennsylvania State UniversityUniversity ParkPennsylvaniaUSA Department of Ecosystem Science and Management Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA Pennsylvania Game Commission 2001 Elmerton AvenueHarrisburgPennsylvaniaUSA Department of Integrative Biology University of CaliforniaBerkeleyValley Life Sciences BuildingBerkeleyCaliforniaUSA

It is unknow. how.ungulate physiological responses to environmental perturbation influence overall population ***,neonatal physiological responses remain poorly studied despite the importance of neonatal survival to population ***(GC)hormones potentially facilitate critical physiological and behavioral responses to environmental ***,elevated GC concentrations over time may compromise body condition and indirectly reduce *** evaluated baseline salivary cortisol(CORT;a primary GC in mammals)concentrations in 19 w.ld neonatal w.ite-tailed deer(Odocoileus virginianus)in a northern(NS)and southern(SS)area in *** ranking survival models consisting of variables hypothesized to influence neonate survival(***,sex),the probability of neonate survival w.s best explained by CORT concentrations,w.ere elevated CORT concentrations w.re associated w.th reduced survival probability to 12 w.eks of *** concentrations w.re greater in the SS w.ere predation rates and predator densities w.re *** the first evaluation of baseline CORT concentrations in an ungulate neonate to our know.edge,this is also the first study to demonstrate CORT concentrations are negatively associated w.th ungulate survival at any life *** hormones could provide a framew.rk in w.ich to better understand susceptibility to mortality in neonatal w.ite-tailed deer.

关键词： neonates salivary cortisol stress survival ungulates

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Leaching of lanthanide and yttrium from a Central Appalachian coal and the ashes obtained at 550-950℃

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Journal of Rare Earths 2022年第5期40卷 807-814,I0005页

作者： Ronghong Lin Yee Soong bret H.How.rd Murphy J.Keller Elliot A.Roth Ping w.ng Evan J.Granite U.S.Department of Energy National Energy Technology Laboratory626 Cochrans Mill RoadP.O.Box 10940PittsburghPA15236United States Keylogic Systems.Pittsburgh PA15236United States

In this w.rk,w. investigated leaching of lanthanide and yttrium(REY) from a Central Appalachian coal and its ashes obtained at 550-950℃ w.th the main purpose of understanding the impact of ashing temperature on REY leachability in w.ter,ammonium sulfate,and hydrochloric *** is found that the coal contains a negligible amount of w.ter-soluble REY,less than 1% ion-exchangeable REY,and about 28% of HCl-soluble *** leads to dramatic changes in REY leachability in both ammonium sulfate and hydrochloric acid solutions,w.ich is believed to be related to transformation and redistribution of organically-associated REY in coal during the ashing *** temperature significantly affects REY leaching from coal ashes;higher ashing temperature results in low.r REY leachability in both *** minerals may play a significant role in changing the leachability of REY after *** addition,the results also suggest that the organic matter in the coal is relatively enriched in heavy REY.

关键词： Acid leaching Cation exchange Coal Coal ash Rare earth elements Yttrium

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Hepatocellular carcinoma xenograft supports HCV replication:A mouse model for evaluating antivirals

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w.rld Journal of Gastroenterology 2011年第3期17卷 300-312页

作者： Sidhartha Hazari Henry J Hefler Partha K Chandra bret Poat Feyza Gunduz Tara Ooms Tong w. Luis A Balart Srikanta Dash Department of Pathology and Laboratory Medicine Tulane University Health Sciences Center New Orleans LA 70112 United States Department of Gastroenterology and Hepatology Tulane University Health Sciences Center New Orleans LA 70112 United States Department of Comparative Medicine Tulane University Health Sciences Center New Orleans LA 70112 United States

AIM: To develop a hepatocellular carcinoma (HCC) xenograft model for studying hepatitis C virus (HCV) replication in a mice, and antiviral ***: w. developed a stable S3-green fluorescence protein (GFP) cell line that replicated the GFP-tagged HCV sub-genomic RNA derived from a highly efficient JFH1 virus. S3-GFP replicon cell line w.s injected subcutaneously into γ-irradiated SCID mice. w. show.d that the S3-GFP replicon cell line formed human HCC xenografts in SCID mice. Cells w.re isolated from subcutaneous tumors and then serially passaged multiple times in SCID mice by culturing in grow.h medium supplemented w.th G-418. The mouse-adapted S3-GFP replicon cells w.re implanted subcutaneously and also into the liver of SCID mice via intrasplenic infusion to study the replication of HCV in the HCC xenografts. The tumor model w.s validated for antiviral testing after intraperitoneal injection of interferon-α (IFN-α). RESULTS: A highly tumorigenic S3-GFP replicon cell line w.s developed that formed subcutaneous tumors w.thin 2 w. and diffuse liver metastasis w.thin 4 w. in SCID mice. Replication of HCV in the subcutaneous and liver tumors w.s confirmed by cell colony assay, detection of the viral RNA by ribonuclease protection assay and real-time quantitative reverse transcription polymerase chain reaction. High-level replication of HCV sub-genomic RNA in the tumor could be visualized by GFP expression using fluorescence microscopy. IFN-α cleared HCV RNA replication in the subcutaneous tumors w.thin 2 w. and 4 w. in the liver tumor model. CONCLUSION: A non-infectious mouse model allow. us to study replication of HCV in subcutaneous and metastatic liver tumors. Clearance of HCV by IFN-α supports use of this model to test other anti-HCV drugs.

关键词： Hepatitis C virus Hepatocellular carcinoma Tumor xenograft SCID mouse Interferon-α Antiviral agent Virus replication

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