检索结果-南通市图书馆

Origin and evolution of palaeok.rst within the Lower Ordovician (Ibexian) Goodwin Formation (Pogonip Group)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Palaeogeography 2012年第1期1卷 57-69页

作者： robert j. k.rvin Adam D. Woods Department of Geological Sciences California State University Fullerton P.O. Box 6850 Fullerton CA 92834-6850 USA Wapiti Energy 800 Gessner Rd. Suite 700 Houston TX 77024 USA

Palaeok.rst within the Lower to Middle Ordovician Goodwin Formation, Pogonip Group (upper Ibexian-lower Whiterock.an) was examined in detail at Meik.ej.hn Peak. Nevada USA in order to determine its origin, evolution, and relationship to sea level change. Detailed outcrop and petrographic examination of dolostone breccias and host rock.reveals that palaeok.rst was formed and affected by two distinct cycles of sea level change. A relative transgression resulted in deposition of lagoonal, ooid shoal, and shallow subtidal facies as sea level rose. Exposure of the carbonate platform led to the formation of multiple phreatic caves below the water table, as well as the development of numerous vadose conduits from the downward percolation of meteoric waters. Vadose water flow through early cave-wall and cave-roof collapse breccias resulted in rounding of smaller breccias clasts via physical transport and corrosion, while subsidence of subsurface k.rst led to the formation of a palaeodoline at the exposure surface. A second relative transgression deposited lagoonal sediments over the older k.rst; subsequent re-exposure of the carbonate platform resulted in the development of small breccia pock.ts as well as grik.s within the youngest lagoonal sediments, and may have led to further corrosion of the older, deeper subsurface k.rst. The distal location of the study area within the carbonate platform suggests k.rst formation was the result of a substantial drop in relative sea level; the presence of multiple generations of palaeok.rst imply that at least two higher-frequency cycles of sea-level change overprint the larger regression.

关键词： palaeok.rst Ordovician carbonates breccia Great Basin

Is plate tectonics needed to evolve technological species on exoplanets?

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2016年第4期7卷 573-580页

作者： robert j.Stern Geoscience Department University of Texas at Dallas

As we continue searching for exoplanets, we wonder if life and technological species capable of communicating with us exists on any of them. As geoscientists, we can also wonder how important is the presence or absence of plate tectonics for the evolution of technological species. This essay considers this question, focusing on tectonically active roclw （silicate） planets, lik. Earth, Venus, and Mars. The development of technological species on Earth provides k.y insights for understanding evolution on exoplanets, including the lik.ly role that plate tectonics may play. An Earth-sized silicate planet is lik.ly to experience several tectonic styles over its lifetime, as it cools and its lithosphere thick.ns, strengthens, and becomes denser. These include magma ocean, various styles of stagnant lid, and perhaps plate tectonics. Abundant liquid water favors both life and plate tectonics. Ocean is required for early evolution of diverse single-celled organisms, then colonies of cells which specialized further to form guts, ap- pendages, and sensory organisms up to the complexity of fish （central nervous system, appendages, eyes）. Large expanses of dry land also begin in the ocean, today produced above subduction zones in j.venile arcs and by their coalescence to form continents, although it is not clear that plate tectonics was required to create continental crust on Earth. Dry land of continents is required for further evolution of technological species, where modification of appendages for grasping and manipulating, and improve- ment of eyes and central nervous system could be perfected. These bioassets allowed intelligent crea- tures to examine the night sk. and wonder, the beginning of abstract think.ng, including religion and science. Technology arises from the exigencies of daily living such as tool-mak.ng, agriculture, clothing, and weapons, but the pace of innovation accelerates once it is allied with science. Finally, the importance of plate tectonics for devel

关键词： Plate tectonics Exoplanets Planetary science Intelligent life

Weight measurement using image-based pose analysis

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2008年第12期18卷 1507-1512页

作者： robert j.Sclabassi Laboratory for Computational Neuroseience Departments of NeurosurgeryElectrical & Computer Engineeringand BioengineeringUniversity of PittsburghPittsburgh 15213USA

Image-based gait analysis as a means of biometric identification has attracted much research *** of the existing methods focus on human identification,posture analysis and movement *** have been few investigations on measuring the carried load based on the carrier’s gait characteristics by automatic image ***,this measurement is very useful in a number of applications,such as the study of the carried load on the postural development of children and *** this paper,we inves- tigate how to automatically estimate the carried weight from a sequence of *** present a method to extract human gait silhouette based on an observation that humans tend to minimize the energy during *** compute several angles of body leaning and deter- mine the relationship of the carried weight,the leaning angles and the centroid location according to a human k.netic *** weight determination method has been verified successfully by experiments.

关键词： Image-based pose analysis Energy minimization Pattern recognition Load carrying measurement

Chinese Secret Societies and Popular Religions Revisited： An Introduction

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Frontiers of History in China 2016年第4期11卷 503-509页

作者： robert j. Antony j.seph Tse-Hei Lee Canton's Thirteen Hongs Research Center Guangzhou University Guangzhou 510006 China Department of History and Confucius Institute Pace University New York NY 10038 USA

It has been over forty years since j.an Chesneaux published his edited volume Popular Movements and Secret Societies in China, and some twenty years since David Ownby and Mary Somers Heidhues published their edited volume Secret Societies Reconsidered On popular religions, both Daniel Overmyer＇s FoItc Buddhist Religion and Susan Naquin＇s Millenarian Rebellion in China were also published almost forty years ago.1 Although there have been a number of important studies published both inside and outside of China on secret societies and popular religions since the 1990s, in recent years there has been a surge in new research, much of it still unpublished, on this important subj.ct in Chinese history.

关键词：

Proximal gastric motility in critically ill patients with type 2 diabetes mellitus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World j.urnal of Gastroenterology 2007年第2期13卷 270-275页

作者： Nam Q Nguyen robert j.Fraser Laura k.Bryant Marianne Chapman Richard H Holloway Department of Gastroenterology Hepatology and General Medicine Royal Adelaide Hospital South Australia Investigation and Procedures Unit Repatriation General Hospital South Australia Anaesthesia and Intensive Care Royal Adelaide Hospital South Australia

AIM： To investigate the proximal gastric motor response to duodenal nutrients in critically ill patients with longstanding type 2 diabetes ***： Proximal gastric motility was assessed （using a barostat） in 10 critically ill patients with type 2 diabetes mellitus （59±3 years） during two 60-min duodenal infusions of Ensure （1 and 2 k.al/min）, in random order, separated by 2h fasting. Data were compared with 15 non-diabetic critically ill patients （48 ± 5 years） and 10 healthy volunteers （28 ±3 years）. RESULTS： Baseline proximal gastric volumes were similar between the three groups. In diabetic patients, proximal gastric relaxation during I k.al/min nutrient infusion was similar to non-diabetic patients and healthy controls. In contrast, relaxation during 2 k.al/ min infusion was initially reduced in diabetic patients （P 〈 0.05） but increased to a level similar to healthy humans, unlik. non-diabetic patients where relaxation was impaired throughout the infusion. Duodenal nutrient stimulation reduced the fundic wave frequency in a dose-dependent fashion in both the critically ill diabetic patients and healthy subj.cts, but not in critically ill patients without diabetes. Fundic wave frequency in diabetic patients and healthy subj.cts was greater than in non-diabetic ***： In patients with diabetes mellitus, proximal gastric motility is less disturbed than nondiabetic patients during critical illness, suggesting that these patients may not be at greater risk.of delayed gastric emptying.

关键词： Proximal gastric function Diabetes mellitus type 2 Critical illness Enteral nutrition

Impact of COVID-19 on Liver Transplant Activity in the USA: Variation by Etiology and Cirrhosis Complications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Clinical and Translational Hepatology 2023年第1期11卷 130-135页

作者： Yong-Fang k.o Paul k.o robert j.Wong Ashwani k.Singal Department of Biostatistics University of Texas Medical BranchGalvestonTXUSA Division of Gastroenterology and Hepatology Veterans Affairs Palo Alto Healthcare SystemStanford University School of MedicinePalo AltoCAUSA University of South Dak.ta Sanford School of MedicineVermillionSDUSA Avera Transplant Institute Sioux FallsSDUSA

Back.round and Aims:The COVID-19 pandemic has impacted the care of patients with liver *** examined impact of COVID-19 on liver transplant(LT)activity in the ***:LT listings in the United Network.for Organ Sharing(UNOS)database(April 2018–May 2021)were analyzed to examine the impact of COVID-19 pandemic on the LT activity based on etiology:hepatitis C virus(HCV),alcohol-associated liver disease(ALD),alcoholic hepatitis(AH),and nonalcoholic steatohepatitis(NASH)complications:hepatocellular carcinoma(HCC)and acute-on-chronic liver failure(ACLF)grade 2 or 3 and Model for End-Stage Liver Disease(MELD)*** regression models assessed time trend changes on a log ***:Of 23,871 recipients(8,995 in the COVID era,April 2018–February 2020),mean age 52 years,62% men,61% Caucasian,32%ALD,15%HCC,30%ACLF grades 2–3,and mean MELD score 20.5,monthly LT changes were a decrease of 3.4%for overall LTs and 22%for HCC after September 2020,and increase of 4.5%for ALD since 11/2020 and 17%since 03/2021 for ACLF grade 2–*** MELD scores increased by 0.7 and 0.36 after j.ne 2020 for HCV and HCC ***:The COVID-19 pandemic has impacted LT activity,with a decrease of LTs especially for HCC,and an increase of LTs for ALD and severe *** are needed to reorganize cirrhosis patients to overcome the aftereffects of COVID-19 pandemic.

关键词： COVID-19 UNOS OLT Region Public policies

INFORMATION SHARING AND STRATEGIC SIGNALING IN SUPPLY CHAINS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

j.urnal of Systems Science and Systems Engineering 2009年第2期18卷 129-158页

作者： robert j.k.UFFMAN Hamid MOHTADI W.P.Carey School of Business and School of Computing and InformaticsArizona State University TempeAZ85287 USA Department of Economics University of WisconsinMilwaukeeWI53201 and Credit Risk AssessmentUSBankMinneapolisMN55402USA

Information sharing in procurement occurs in rich and varied industry contexts in which managerial decisions are made and organizational strategy is formulated. We explore how information sharing ought to work.in procurement contexts that involve investments in inter-organizational information systems （IOS） and collaborative planning, forecasting and replenishment （CPFR） practices. How and under what circumstances does a firm that plays the role of a supply chain buyer decide to share information on k.y variables, such as point-of-sale consumer demand data with its supplier, up the supply chain？ This is a k.y issue that crosses the boundary between supply chain management and information systems （IS） management. The answers that we provide are based on our use of a game-theoretic signaling model of buyer and supplier strategy in the presence of uncertainties about final consumer demand. We also explore the connection between operational costs that are associated with the firm＇s information sharing and information withholding strategies. Our results provide normative guidance to supply chain buyers about how to interpret different demand uncertainty scenarios to improve their decisions and generate high value. From the IS management perspective, we show the impacts on the firm of different information sharing approaches that are made possible by present day technologies.

关键词： Anticipated over-supply collaborative planning forecasting and replenishment (CPFR) demand forecasting economic analysis information sharing information systems (IS) signaling supply chain management

Wavelet denoising via sparse representation

在线全文

学校读者我要写书评

暂无评论

Science in China(Series F) 2009年第8期52卷 1371-1377页

作者： ZHAO RuiZhen LIU XiaoYu Ching-Chung LI robert j. SCLABASSI & SUN MinGui Institute of Information Science Beijing Jiaotong University Beijing 100044 China Department of Neurosurgery University of Pittsburgh Pittsburgh PA 15261 USA Department of Electrical & Computer Engineering University of Pittsburgh Pittsburgh PA 15261 USA

Wavelet threshold denoising is a powerful method for suppressing noise in signals and images. However, this method often uses a coordinate-wise processing scheme, which ignores the structural properties in the wavelet coefficients. We propose a new wavelet denoising method using sparse representation which is a powerful mathematical tool recently developed. Instead of thresholding wavelet coefficients individually, we minimize the number of non-zero coefficients under certain conditions. The denoised signal is reconstructed by solving an optimization problem. It is shown that the solution to the optimization problem can be obtained uniquely and the estimates of the denoised wavelet coefficients are unbiased, i.e., the statistical means of the estimates are equal to the noise-free wavelet coefficients. It is also shown that at least a local optimal solution to the denoising problem can be found. Our experiments on test data indicate that this new denoising method is effective and efficient for a wide variety of signals including those with low signal-to-noise ratios.

关键词： signal processing denoising sparse representation wavelet transform

Eastern gray squirrels are consistent shoppers of seed traits:insights from discrete choice experiments

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2018年第3期13卷 280-296页

作者： Mek.la SUNDARAM Nathanael I.LICHTI Nicole j.Olynk.WIDMAR robert k.SWIHART Department of Forestry and Natural Resources Purdue UniversityWest LafayetteIndianaUSA Department of Agricultural Economics Purdue UniversityWest LafayetteIndianaUSA

Seeds of many hardwood trees are dispersed by scatter-hoarding rodents,and this process is often mediated by the traits of *** numerous studies have link.d seed traits to seed preference by rodents,little is k.own about how rodents forage for seeds when multiple desirable and undesirable seed traits are available ***,we adopt a novel method of designing choice experiments to study how eastern gray squirrels(Sciurus carolinensis)select for 6 traits(caloric value,protein content,tannin concentration,k.rnel mass,dormancy period and toughness of shell)among *** n=426 seed-pair presentations,we found that squirrels preferentially consumed seeds with short dormancy or tougher shells,and preferentially cached seeds with larger k.rnel mass,tougher shells and higher tannin *** incorporating random effects,we found that squirrels exhibited consistent preferences for seed traits,which is lik.ly due to the fitness consequences associated with maintaining cached ***,we found that squirrels were willing to trade between multiple traits when caching seeds,which lik.ly results in more seed species being cached in the ***,our approach allowed us to compute the relative values of different seed traits to squirrels,despite covariance among studied traits across seed *** addition,by investigating how squirrels trade among different seed traits,important insights can be gleaned into behavioral mechanisms underlying seed caching(and,thus,seed survival)dynamics as well as evolutionary strategies adopted by plants to attract seed *** describe how discrete choice experiments can be used to study resource selection in other ecological systems.

关键词： cached resources discrete choice experiment resource selection trade-offs trait-dependent