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Does the mcNeill Alexander model accurately predict maximum walking speed in novice and experienced race walkers？

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Journal of Sport and Health Science 2018年第3期7卷 372-377页

作者： Andrew J.Harrison patrick G.molloy Laura-Anne m.Furlong Department of Physical Education and Sport Sciences University of LimerickCastletroyLimerick V94 T9PXIreland School of Sport Exercise and Health Sciences Loughborough UniversityEpinalWayLoughboroughLeicestershire LEll 3TUUK

Background:mathematical models propose leg length as a limiting factor in determining the maximum walking *** study evaluated the effectiveness of a leg length-based model in predicting maximum walking velocity in an applied race walking situation,by comparing experienced and novice race walkers during conditions where strictly no flight time(FT)was permitted and in simulated competition conditions(i.e.,FTms).methods:Thirty-four participants(18 experienced and l6 novice race walkers)were recruited for this *** Optojump Next system(8 m)was used to determine walking velocity,step frequency,step length,ground contact time,and FT during race walking over a range of *** were made between novice and experienced participants in predicted maximum velocity and actual velocities achieved with no flight and velocities with FTmaximum velocity to predicted ***:In novices,no significant difference was found between predicted and maximum walking speeds without FT but there was a small 5.8%gain in maximum speed when FT≤40 *** experienced race walkers,there was a significant reduction in maximum walking speed compared with predicted maximum(pmaximum walking speed with FTmaximal walking velocity in novice walkers but not a good predictor of maximum walking speed in well-trained walkers who appear to have optimised their walking technique to make use of non-visible flight periods of less than 40 *** gain in velocity above predicted maximum may be a useful index of race walking proficiency.

关键词： Biomechanics Gait mathematical modelling Race walking Sports technique Technique development

Adopting novel ecosystems as suitable rehabilitation alternatives for former mine sites

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Ecological Processes 2013年第1期2卷 221-231页

作者： David Doley patrick Audet Centre for mined Land Rehabilitation Sustainable Minerals InstituteThe University of QueenslandBrisbane(St.Lucia)QLD 4072Australia

The nature and extent of environmental disturbance associated with mining commonly entails completely new and challenging combinations of climate,lithology and ***,the outcomes of ecological processes associated with the recovery or restoration of ecosystems cannot be predicted reliably from previously known associations between their physical and biological *** radically disturbed sites,we propose that it is not practicable to aim for the restoration of historical ***,hybrid(reversibly different)or novel(irreversibly different)ecosystems comprising new combinations of physical and biological components,including both native and non-native species,could provide levels of stability and functionality acceptable to all stakeholders and within feasible management *** propose that limiting physical conditions of the landscape can be identified and managed,and that alternative species combinations for introduction to these new landscapes may be considered with cautious optimism.

关键词： Natural ecological analogues Novel ecosystems mining Landscape suitability

Liquid vaporization under thermodynamic phase non-equilibrium condition at the gas-liquid interface

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Science China(Technological Sciences) 2020年第12期63卷 2649-2656页

作者： WANG XingJian LAFON patrick SUNDARAm Dilip YANG Vigor Department of mechanical and Civil Engineering Florida Institute of TechnologyMelbourneFlorida 32901USA Department of mechanical and Nuclear Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA School of Aerospace Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Liquid vaporization under thermodynamic phase non-equilibrium condition at the gas-liquid interface is investigated over a wide range of fluid state typical of many liquid-fueled energy conversion systems. The validity of the phase-equilibrium assumption commonly used in the existing study of liquid vaporization is examined using molecular dynamics theories. The interfacial mass flow rates on both sides of the liquid surface are compared to the net vaporization rate through an order-of-magnitude *** indicated that the phase-equilibrium assumption holds valid at relatively high pressures and low temperatures,and for droplets with relatively large initial diameters(for example,larger than 10 μm for vaporizing oxygen droplets in gaseous hydrogen in the pressure range from 10 atm to the oxygen critical state). Droplet vaporization under superheated conditions is also explored using classical binary homogeneous nucleation theory,in conjunction with a real-fluid equation of state. It is found that the bubble nucleation rate is very sensitive to changes in saturation ratio and pressure;it increases by several orders of magnitude when either the saturation ratio or the pressure is slightly increased. The kinetic limit of saturation ratio decreases with increasing pressure,leading to reduced difference between saturation and superheat conditions. As a result,the influence of nonequilibrium conditions on droplet vaporization is lower at a higher pressure.

关键词： liquid vaporization droplet vaporization superheated vaporization thermodynamic phase equilibrium thermodynamic phase non-equilibrium vapor nucleation

Assessing the performance of different outcomes for tumor growth studies with animal models

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Animal models and Experimental medicine 2022年第3期5卷 248-257页

作者： Luke W.Patten patrick Blatchford matthew Strand Alexander m.Kaizer Department of Biostatistics and Informatics University of ColoradoAuroraColoradoUSA

The consistency of reporting results for patient-derived xenograft(PDX) studies is an area of concern. The PDX method commonly starts by implanting a derivative of a human tumor into a mouse, then comparing the tumor growth under different treatment conditions. Currently, a wide array of statistical methods(e.g., t-test, regression, chi-squared test) are used to analyze these data, which ultimately depend on the outcome chosen(e.g., tumor volume, relative growth, categorical growth). In this simulation study, we provide empirical evidence for the outcome selection process by comparing the performance of both commonly used outcomes and novel variations of common outcomes used in PDX studies. Data were simulated to mimic tumor growth under multiple scenarios, then each outcome of interest was evaluated for 10?000 iterations. Comparisons between different outcomes were made with respect to average bias, variance, type-1 error, and power. A total of 18 continuous, categorical, and time-to-event outcomes were evaluated, with ultimately 2 outcomes outperforming the others: final tumor volume and change in tumor volume from ***, the novel variations of the tumor growth inhibition index(TGII)— a commonly used outcome in PDX studies— was found to perform poorly in several scenarios with inflated type-1 error rates and a relatively large bias. Finally, all outcomes of interest were applied to a real-world dataset.

关键词： mouse model oncology outcome selection patient-derived xenograft(PDX) statistical analysis TGII translational science

Patterns of reptile and amphibian species richness along elevational gradients in mt. Kenya

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Zoological Research 2015年第6期36卷 342-347页

作者： patrick Kinyatta mALONZA National museums of Kenya Herpetology Section

Faunal species richness is traditionally assumed to decrease with increasing elevation and decreasing prmary productivity. Species richness is reported to peak at mid-elevation. This survey examines the herpetofaunal diversity and distribution in mt. Kenya （central Kenya） by testing the hypothesis that changes in species richness with elevation relate to elevation-dependent changes in climate. Sampling along transects from an elevation of approximately 1 700 m in Chogoda forest block （wind-ward side） and approximately 2 600 m in Sirimon block （rain shadow zone） upwards in march 2009. This starts from the forest to montane alpine zones. Sampling of reptiles and amphibians uses pitfall traps associated with ddfl fences, time-limited searches and visual encounter surveys. The results show that herpetofaunal richness differs among three vegetation zones along the elevation gradient. Chogoria has higher biodiversity than Sirimon. more species occur at low and middle elevations and few exist at high elevations. The trends are consistent with expected optimum water and energy variables. The lower alpine montane zone has high species richness but low diversity due to domi- nance of some high elevations species. Unambiguous data do not support a mid-domain effect （mid-elevation peak） because the observed trend better fits a model in which climatic variables （rainfall and temperature） control species richness, which indirectly measures productivity. It is important to continue protection of all indigenous forests, especially at low to mid elevations. These areas are vulnerable to human destruction yet are home to some endemic species. Firebreaks can limit the spread of the perennial wildfires, especially on the moor- lands.

关键词： Herpetofauna Elevation Rainfall Temperature Species diversity

Hepatocellular carcinoma surveillance:An evidence-based approach

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World Journal of Gastroenterology 2019年第13期25卷 1550-1559页

作者： patrick S Harris Ross m Hansen meagan E Gray Omar I massoud Brendan m mcGuire mohamed G Shoreibah Tinsley Harrison Internal medicine Residency Program Department of Medicine University of Alabama at Birmingham Division of Gastroenterology and Hepatology Department of Medicine University of Alabama at Birmingham

Hepatocellular carcinoma(HCC) makes up 75%-85% of all primary liver cancers and is the fourth most common cause of cancer related death worldwide. Chronic liver disease is the most significant risk factor for HCC with 80%-90% of new cases occurring in the background of cirrhosis. Studies have shown that early diagnosis of HCC through surveillance programs improve prognosis and availability of curative therapies. All patients with cirrhosis and high-risk hepatitis B patients are at risk for HCC and should undergo surveillance. The recommended surveillance modality is abdominal ultrasound(US) given that it is cost effective and noninvasive with good sensitivity. However, US is limited in obese patients and those with non-alcoholic fatty liver disease(NAFLD). With the current obesity epidemic and rise in the prevalence of NAFLD, abdominal computed tomography or magnetic resonance imaging may be indicated as the primary screening modality in these patients. The addition of alpha-fetoprotein to a surveillance regimen is thought to improve the sensitivity of HCC *** investigation of serum biomarkers is needed. Semiannual screening is the suggested surveillance interval. Surveillance for HCC is underutilized and low adherence disproportionately affects certain demographics such as nonCaucasian race and low socioeconomic status.

关键词： Liver cancer Hepatocellular carcinoma Surveillance

Treatment of colonic varices and gastrointestinal bleeding by recanalization and stenting of splenic-vein-thrombosis:A case report and literature review

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World Journal of Gastroenterology 2023年第24期29卷 3922-3931页

作者： Lisa-michaela Füssel Rene müller-Wille patrick Dinkhauser Walter Schauer Harald Hofer Department of Internal medicine Ⅰ Gastroenterology and HepatologyKlinikum Wels-GrieskirchenWels 4600Austria Department of Radiology Klinikum Wels-GrieskirchenWels 4600Austria Department of Abdominal Surgery Klinikum Wels-GrieskirchenWels 4600Austria

BACKGROUND Splenic vein thrombosis is a known complication of *** can lead to increased blood flow through mesenteric *** segmental hypertension may result in the development of colonic varices(CV)with a high risk of severe gastrointestinal *** clear guidelines for treatment are lacking,splenectomy or splenic artery embolization are often used to treat *** vein stenting has been shown to be a safe *** SUmmARY A 45-year-old female patient was admitted due to recurrent gastrointestinal *** was anemic with a hemoglobin of 8.0 g/*** a source of bleeding,CV were *** tomography scans revealed thrombotic occlusion of the splenic vein,presumably as a result of a severe acute pancreatitis 8 years *** a selective angiography,a dilated mesenterial collateral leading from the spleen to enlarged vessels in the right colonic flexure and draining into the superior mesenteric vein could be *** hepatic venous pressure gradient was within normal *** an interdisciplinary board,transhepatic recanalization of the splenic vein via balloon dilatation and consecutive stenting,as well as coiling of the aberrant veins was discussed and successfully *** evaluation revealed complete regression of CV and splenomegaly as well as normalization of the red blood cell count during *** Recanalization and stenting of splenic vein thrombosis might be considered in patients with gastrointestinal bleeding due to ***,a multidisciplinary approach with a thorough workup and discussion of individualized therapeutic strategies is crucial in these difficult to treat patients.

关键词： Pancreatitis-induced splenic vein thrombosis Gastrointestinal hemorrhage Colonic varices Splenic vein stenting Segmental/sinistral hypertension Case report

The clinical rehabilitation of spine and spinal cord disorders: detection and evaluation using SPECT/CT

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Neural Regeneration Research 2014年第8期9卷 795-797页

作者： max J. Scheyerer Clément m.L.Werner patrick Veit-Haibach Centre for Orthopaedic and Trauma Surgery University Medical CenterJosef-Stelzmann-Str.9CologneGermany Department of Surgery Division of TraumaSurgeryUniversity Hospital ZurichZurichSwitzerland Department of medical Radiology Division of Nuclear MedicineUniversity Hospital ZurichZurichSwitzerland Department of medical Radiology Diagnostic and Inverventional Radiolo-gyUniversity Hospital ZurichZurichSwitzerland

Spine-related disorders are caused by several factors including （1） spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, （2） spinal nerve/visceral nerve compression by injured periverterbal soft tissue, dislocated perivertebral small joint, and proliferative/degenerative tissue and, （3） secondary damage to the spinal cord, peripheral nerve, vessels and autonomic nerve, which further stimulate nerve root sheath and surround- ing pain-carrying nerve fibers. In many cases, the source of pain cannot be detected by standard image modalities. Particularly in anatomically complex regions like the spine, SPECT/CT can be helpful for some aspects by intro- ducing a metabolical dimension to the classical way of morphology-based diagnostic. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical spine-focused setting.

关键词： SPECT The clinical rehabilitation of spine and spinal cord disorders detection and evaluation using SPECT/CT

Architecting Fault Tolerance with Exception Handling: Verification and Validation

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Journal of Computer Science & Technology 2009年第2期24卷 212-237页

作者： patrick H. S. Brito Rogério de Lemos Cecília m. F. Rubira Eliane martins Institute of Computing State University of Campinas Brazil Computing Laboratory University of Kent U.K.

When building dependable systems by integrating untrusted software components that were not originally designed to interact with each other, it is likely the occurrence of architectural mismatches related to assumptions in their failure behaviour. These mismatches, if not prevented during system design, have to be tolerated during runtime. This paper presents an architectural abstraction based on exception handling for structuring fault-tolerant software systems. This abstraction comprises several components and connectors that promote an existing untrusted software element into an idealised fault-tolerant architectural element. moreover, it is considered in the context of a rigorous software development approach based on formal methods for representing the structure and behaviour of the software architecture. The proposed approach relies on a formal specification and verification for analysing exception propagation, and verifying important dependability properties, such as deadlock freedom, and scenarios of architectural reconfiguration. The formal models are automatically generated using model transformation from UmL diagrams： component diagram representing the system structure, and sequence diagrams representing the system behaviour. Finally, the formal models are also used for generating unit and integration test cases that are used for assessing the correctness of the source code. The feasibility of the proposed architectural approach was evaluated on an embedded critical case study.

关键词： exception handling fault-tolerant software architecture model-based test model checking software verification and validation