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Solving for the Fixed Points of 3-Cycle in the Logistic map and Toward Realizing Chaos by the Theorems of Sharkovskii and Li–Yorke

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Communications in Theoretical Physics 2014年第10期61卷 485-496页

作者： m.howard Lee Department of Physics and Astronomy University of GeorgiaAthensGA 30602USA Korea institute for Advanced Study Seoul 130-012Korea

Sharkovskii proved that, for continuous maps on intervals, the existence of 3-cycle implies the existence of all others. Li and Yorke proved that 3-cycle implies chaos. To establish a domain of uncountable cycles in the logistic map and to understand chaos in it, the fixed points of 3-cycle are obtained analytically by solving a sextic equation. At one parametric value, a fixed-point spectrum, resulted from the Sharkovskii limit, helps to realize chaos in the sense of Li and Yorke.

关键词： logistic map chaos 3-cycle fixed points Sharkovskii theorem Li-Yorke theroem

Coronavirus Disease 2019 and Liver injury:A Retrospective Analysis of Hospitalized Patients in New York City

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Journal of Clinical and Translational Hepatology 2021年第4期9卷 551-558页

作者： Joshua m.Bender howard J.Worman Department of medicine Vagelos College of Physicians&SurgeonsColumbia UniversityNew YorkNYUSA Department of Pathology and Cell Biology Vagelos College of Physicians&SurgeonsColumbia UniversityNew YorkNYUSA

Background and Aims:Coronavirus disease 2019(COViD-19)is a global threat,affecting more than 100 million people and causing over 2 million *** laboratory test abnormalities are an extrapulmonary manifestation of COViD-19,yet characterization of hepatic injury is *** objective was to further characterize and identify causes of liver injury in patients with ***:We conducted a retrospective cohort study of 551 patients hospitalized with COViD-19 at NewYork-Presbyterian Hospital/Columbia University irving medical Center between march 1,2020 and may 31,*** analyzed patient demographics,liver laboratory test results,vital signs,other relevant test results,and clinical outcomes(mortality and intensive care unit admission).Results:Abnormal liver laboratory tests were common on hospital admission for COViD-19 and the incidence increased during *** those with elevated serum alanine aminotransferase and/or alkaline phosphatase activities on admission,58.2%had a cholestatic injury pattern,35.2%mixed,and 6.6%*** liver disease was not associated with outcome;however,abnormal direct bilirubin or albumin on admission were associated with intensive care unit stay and *** average,patients who died had greater magnitudes of abnormalities in all liver laboratory tests than those who *** hepatitis was a mechanism of severe hepatocellular injury in some ***:Liver laboratory test abnormalities are common in hospitalized patients with COViD-19,and some are associated with increased odds of intensive care unit stay or *** hepatocellular injury is likely attributable to secondary effects such as systemic inflammatory response syndrome,sepsis,and ischemic hepatitis.

关键词： Aminotransferase Bilirubin ischemic hepatitis SARS-CoV-2

Surfactant protein A (SP-A) binds to phosphatidylserine and competes with annexin V binding on late apoptotic cells

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Protein & Cell 2010年第2期1卷 188-197页

作者： Anne Jäkel Kenneth B.m.Reid howard Clark Department of Pharmacology University of OxfordMansfield RoadOxford OX13QTUK mRC immunochemistry Unit Department of BiochemistryUniversity of OxfordSouth Parks RoadOxford OX13QUUK University of Southampton MP 803 Level FSouth BlockSouthampton General HospitalSouthampton SO166YDUK

The role of surfactant protein A(SP-A)in the recognition and clearance of apoptotic cells is well established,but to date,it is still not clear which surface molecules of apoptotic cells are involved in the *** we present evidence that phosphatidylserine(PS)is a relevant binding molecule for human *** binding is Ca^(2+)-dependent and is not inhibited by mannose,suggesting that the sugar-binding site of the carbohydrate recognition domain(CRD)of SP-A is not *** cytometry studies on apoptotic Jurkat cells revealed apparent inhibition of annexin V binding by increasing concentrations of SP-A in late apoptotic but not early apoptotic cells,and this was consistent for Jurkat cells and *** these data,confocal microscopy results show a co-localisation of annexin V and SP-A in late apoptotic but not early apoptotic ***,we cannot conclude that this inhibition is exclusively due to the binding of SP-A to PS on the cell surface,as annexin V is not wholly specific for PS and SP-A also interacts with other phospholipids that might become exposed on the apoptotic cell surface.

关键词： surfactant proteins phosphatidylserine apoptotic cells

Potential gains from spatially-explicit coordinated planning between two large public ownerships in minnesota

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Forest Ecosystems 2019年第2期6卷 102-118页

作者： Joshua J. Bixby howard m. Hoganson Yu Wei Geospatial Systems Engineer USDA Forest Service Chief’s Information Office Duluth MN USA Department of Forest Resources and North Central Research and Outreach Center University of MN Grand Rapids MN USA Department of Forest and Rangeland Stewardship Colorado State University Fort Collins CO USA

Background: many forested landscapes throughout the world involve a mix of public forest ownerships. This study explores how coordinated planning between two large public ownerships in minnesota impact landscape-level trade-offs between timber production and production of core area of older forest (COF) for the region. COF is an important metric for wildlife habitat. Emphasis is on better understanding potential gains from both coordinated planning at the site-level where ownerships share stand boundaries and from coordinated planning at a broader policy level involving assumed values of COF by the public. The study area involves over 300,000 ha, 150,000 analysis units and a 100-year planning horizon. methods: The concept of influence zones in modeling spatial interdependencies is described and implemented. The estimated total area of COF is assumed an important landscape metric for forest wildlife habitat condition for each forest planning period. COF has a surrounding buffer protecting it from edge effects. Differences are recognized between COF condition requirements and condition requirements for its surrounding buffer. A spatially-explicit harvest scheduling model is applied in conjunction with moving-windows techniques of GiS to find near-optimal management schedules for the large landscape. multiple model runs are examined to help better understand both potential gains from coordinated planning and the tradeoffs between timber and COF production. Results: Results demonstrate the ability to incorporate detailed site-level COF production into management scheduling models for broad, landscape-level planning. For the study area and the assumed COF definitions, substantially larger gains are possible by coordinating COF value assumptions across ownerships, as compared to possible gains from coordinating on-the-ground management activities in areas involving shared stand boundaries. Although a general map of the study area shows a definite intertwining mosaic of ow

关键词： Core area interior space Trade-off analysis multiple objective planning Landscape planning Harvest scheduling Patch size Production possibilities frontier

An in Vivo Experimental Validation of a Computational model of Human Foot

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Journal of Bionic Engineering 2009年第4期6卷 387-397页

作者： Christopher J.Nester David howard Centre for Health Sport and Rehabilitation Sciences ResearchUniversity of Salford Salford M5 4WTUK

Reliable computational foot models offer an alternative means to enhance knowledge on the biomechanics of human foot. model validation is one of the most critical aspects of the entire foot modeling and analysis *** paper presents an in vivo experiment combining motion capture system and plantar pressure measure platform to validate a three-dimensional finite element model of human *** magnetic Resonance imaging(mRi)slices for the foot modeling and the experimental data for validation were both collected from the same volunteer *** validated components included the comparison of static model predictions of plantar force,plantar pressure and foot surface deformation during six loading conditions,to equivalent measured *** the whole experiment,foot surface deformation,plantar force and plantar pressure were recorded simultaneously during six different loaded standing *** predictions of the current FE model were in good agreement with these experimental results.

关键词： human foot computational model plantar pressure

The tectonics and mineral systems of Proterozoic Western Australia:Relationships with supercontinents and global secular change

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Geoscience Frontiers 2018年第2期9卷 295-316页

作者： A.R.A.Aitken S.A.Occhipinti m.D.Lindsay A.Joly H.m.howard S.P.Johnson J.A.Hollis C.V.Spaggiari i.m.Tyler T.C.mcCuaig m.C.Dentith Centre for Exploration Targeting The University of Western AustraliaPerthWestern AustraliaAustralia The Geological Survey of Western Australia Department of Mines and PetroleumPerthWestern AustraliaAustralia BHP Billiton 125 St Georges TerracePerthAustralia ARC Centre of Excellence for Core to Crust Fluid Systems Centre for Exploration TargetingSchool of Earth SciencesThe University of Western AustraliaAustralia Resource Potentials PerthAustralia Department of Geology The Ministry of Mineral ResourcesGreenland GovernmentGreenland

The cratonisation of Western Australia during the Proterozoic overlapped with several key events in the evolution of Earth. These include global oxidation events and glaciations, as well as the assembly,accretionary growth, and breakup of the supercontinents Columbia and Rodinia, culminating in the assembly of Gondwana. Globally, Proterozoic mineral systems evolved in response to the coupled evolution of the atmosphere, hydrosphere, biosphere and lithosphere. Consequently, mineral deposits form preferentially in certain times, but they also require a favourable tectonic setting. For Western Australia a distinct plate-margin mineralisation trend is associated with Columbia, whereas an intraplate mineralisation trend is associated with Rodinia and Gondwana, each with associated deposit types. We compare the current Proterozoic record of ore deposits in Western Australia to the estimated likelihood of oredeposit formation. Overall likelihood is estimated with a simple matrix-based approach that considers two components: The "global secular likelihood" and the "tectonic setting likelihood". This comparative study shows that at least for the studied ore-deposit types, deposits within Western Australia developed at times, and in tectonic settings compatible with global databases. Nevertheless, several deposit types are either absent or poorly-represented relative to the overall likelihood models. insufficient exploration may partly explain this, but a genuine lack of deposits is also suggested for some deposit types. This may relate either to systemic inadequacies that inhibited ore-deposit formation, or to poor preservation. The systematic understanding on the record of Western Australia helps to understand mineralisation processes within Western Australia and its past connections in Columbia, Rodinia and Gondwana and aids to identify regions of high exploration potential.

关键词： mineral systems Tectonics Australia

Surface-bound myeloperoxidase is a ligand for recognition of late apoptotic neutrophils by human lung surfactant proteins A and D

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Protein & Cell 2010年第6期1卷 563-572页

作者： Anne Jäkel howard Clark Kenneth B.m.Reid Robert B.Sim Department of Pharmacology University of OxfordMansfield RoadOxford OX13QTUK University of Southampton School of MedicineDivision of Infection Inflammation&ImmunitySouthampton General HospitalSouthampton SO166YDUK mRC immunochemistry Unit Department of BiochemistryUniversity of OxfordSouth Parks RoadOxford OX13QUUK

Surfactant proteins A(SP-A)and D(SP-D),both members of the collectin family,play a well established role in apoptotic cell recognition and *** in vitro data show that SP-A and SP-D interact with apoptotic neutrophils in a distinct ***-A and SP-D bind in a Ca^(2+)-dependent manner to viable and early apoptotic neutrophils whereas the much greater interaction with late apoptotic neutrophils is Ca^(2+)-*** surface molecules on the apoptotic target cells responsible for these interactions had not been identified and this study was done to find candidate target ***(mPO),a specific intracellular defense molecule of neutrophils that becomes exposed on the outside of the cell upon apoptosis,was identified by affinity purification,mass-spectrometry and western blotting as a novel binding molecule for SP-A and *** confirm its role in recognition,it was shown that purified immobilised mPO binds SP-A and SP-D,and that mPO is surface-exposed on late apoptotic ***-A and SP-D inhibit binding of an anti-mPO monoclonal Ab to late apoptotic *** microscopy confirmed that anti-mPO mAb and SP-A/SP-D colocalise on late apoptotic *** was identified as a further potential ligand for SP-A,and neutrophil defensin as a target for both proteins.

关键词： SP-A SP-D myeloperoxidase neutrophils flow cytometry mass spectrometry

Social interactions in a solitary carnivore

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Current Zoology 2017年第4期63卷 357-362页

作者： L. mark ELBROCH howard QUiGLEY Panthera 8 West 40th Street 18th Floor New York NY 10018 USA

in total, 177 of 245 terrestrial carnivores are described as solitary, and much of carnivore ecology is built on the assumptions that interactions between adult solitary carnivores are rare. We employed Global Positioning System （GPS） technology and motion-triggered cameras to test predictions of land-tenure territoriality and the resource dispersion hypothesis in a territorial carnivore, the puma Puma concolor. We documented 89 independent GPS interactions, 60% of which occurred at puma kills （n=53）, 59 camera interactions, 11 （17%） of which captured courtship behaviors, and 5 other interactions （1 F-F, 3 m-F, and 1 m-m）. mean minimum weekly contact rates were 5.5 times higher in winter, the season when elk Cervus elaphus were aggregated at lower elevations and during which puma courtship primarily occurred. in winter, contacts rates were 0.6_＋ 0.3 （standard devi- ation （SD）） interactions/week vs. 0.1 _＋ 0.1 （SD） interactions/week during summer. The preponder- ance of interactions at food sources supported the resource dispersion hypothesis, which predicts that resource fluxes can explain temporary social behaviors that do not result in any apparent benefits for the individuals involved. Conspecific tolerance is logical when a prey is so large that the predator that killed it cannot consume it entirely, and thus, the costs of tolerating a conspecific sharing the kill are less than the potential costs associated with defending it and being injured. Puma aggregations at kills numbered as high as 9, emphasizing the need for future research on what explains tolerance among solitary carnivores.

关键词： carnivores competition Puma concolor resource dispersion hypothesis social interactions tolerance.

Preoperative bowel preparation does not favor the management of colorectal anastomotic leak

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World Journal of Gastrointestinal Surgery 2019年第4期11卷 218-228页

作者： Konstantinos A Zorbas Daohai Yu Aruj Choudhry howard m Ross matthew Philp Department of Surgery BronxCare Health System Department of Surgery Lewis Katz School of Medicine Temple University Department of Clinical Sciences Lewis Katz School of Medicine Temple University

BACKGROUND Controversy exists regarding the impact of preoperative bowel preparation on patients undergoing colorectal surgery. This is due to previous research studies,which fail to demonstrate protective effects of mechanical bowel preparation against postoperative complications. However, in recent studies, combination therapy with oral antibiotics(OAB) and mechanical bowel preparation seems to be beneficial for patients undergoing an elective colorectal *** To determine the association between preoperative bowel preparation and postoperative anastomotic leak management(surgical vs non-surgical).mETHODS Patients with anastomotic leak after colorectal surgery were identified from the 2013 and 2014 Colectomy Targeted American College of Surgeons National Surgical Quality improvement Program(ACS-NSQiP) database and were employed for analysis. Every patient was assigned to one of three following groups based on the type of preoperative bowel preparation: first groupmechanical bowel preparation in combination with OAB, second groupmechanical bowel preparation alone, and third group-no *** A total of 652 patients had anastomotic leak after a colectomy from January 1,2013 through December 31, 2014. Baseline characteristics were assessed and found that there were no statistically significant differences between the three groups in terms of age, gender, race, American Society of Anesthesiologists score,and other preoperative characteristics. A χ~2 test of homogeneity was conducted and there was no statistically/clinically significant difference between the three categories of bowel preparation in terms of *** The implementation of mechanical bowel preparation and antibiotic use in patients who are going to undergo a colon resection does not influence the treatment of any possible anastomotic leakage.

关键词： Preoperative bowel preparation Preoperative mechanical bowel preparation Preoperative oral antibiotics Colorectal anastomotic leak Anastomotic leak Bowel preparation Colorectal surgery National Surgical Quality improvement Program