检索结果-南通市图书馆

Overhead shoulder press - In-front of the head or behind the head？

在线全文

学校读者我要写书评

暂无评论

j.urnal of Sport and Health Science 2015年第3期4卷 250-257页

作者： mark R. McKean Brendan j. Burkett Faculty of Science Health and Education School of Health and Sport Sciences University of the Sunshine Coast Sippy Downs Queensland 4556 A ustralia

Background： Using a cross-sectional design comparison, two overhead press techniques （in-front of the head or behind the head） were compared. The purpose of this study was to determine the impact of behind the head or in-front of the head overhead pressing technique on shoulder range of movement （ROM） and spine posture. The overhead press is commonly prescribed exercise. The two techniques （in-front of the head or behind the head） may influence j.int mechanics and therefore require an obj.ctive analysis. Methods： Passive shoulder ROM quantified using goniometric measures, dynamic ROM utilised three-dimensional （3D） biomechanical mea- sures （120 Hz） of 33 participants performing overhead pressing in a seated position. The timing and synchronisation of the upper limb shoulder and spine segments were quantified and influence of each technique was investigated. Results： The in-front technique commenced in lordotic position, whilst behind the head technique commenced in kyphotic position. Behind the head technique started with less thoracic extension than in-front condition. The thoracic spine remained extended and moved between 12~ and 15~ regardless of gender or technique. The techniques resulted in a significant difference between genders. Males were able to maintain a flat or normal lumbar lordosis, whereas females tended to kyphotic. Conclusion： Shoulder ROM was within passive ROM for all measures except external rotation for males with the behind the head technique. To avoid possible inj.ry passive ROM should be increased prior to behind the head protocol. Females showed greater spine movements, suggesting trunk strengthening may assist overhead pressing techniques. For participants with normal trunk stability and ideal shoulder ROM, overhead pressing is a safe exercise （for the shoulder and spine） when performed either in-front of or behind the head.

关键词： 3RM Head ROM Shoulder flexibility Shoulder press Spine flexion

On Some Numbers Related to the Erdös-Szekeres Theorem

在线全文

学校读者我要写书评

暂无评论

Open j.urnal of Discrete Mathematics 2013年第3期3卷 167-173页

作者： mark j. Nielsen William Webb Department of Mathematics University of Idaho Moscow City Moscow Department of Mathematics Washington State University Pullman USA

A crossing family of segments is a collection of segments each pair of which crosses. Given positive integers j.and k,a(j.k) grid is the union of two pairwise-disj.int collections of segments (with j.and k members, respectively) such that each segment in the first collection crosses all members of the other. Let c(k) be the least integer such that any planar set of c(k) points in general position generates a crossing family of k segments. Also let #(j.k) be the least integer such that any planar set of #(j.k) points in general position generates a (j.k)-grid. We establish here the facts 9≤c(3)≤16 and #(1,2)=8.

关键词： Erdos-Szekeres Theorem Combinatorial Geometry

Root-Specific Transcript Profiling of Contrasting Rice Genotypes in Response to Salinity Stress

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2011年第1期4卷 25-41页

作者： Olivier Cotsaftis Darren Plett Alexander A.T. j.hnson Harkamal Walia Clyde Wilson Abdelbagi M. Ismail Timothy j. Close mark Tester Ute Baumann Australian Centre for Plant Functional Genomics Private Mail Bag 1 Glen Osmond SA 5064 Australia Present address: School of Botany University of Melbourne Parkville Vic 3010 Australia Department of Botany and Plant Sciences University of California Riverside CA 92521 USA Present address: Department of Agronomy and Horticulture University of Nebraska Lincoln NE 68588 USA United States Department of Agriculture Agricultural Research Service George E. Brown Jr Salinity Laboratory Riverside CA 92507 USA International Rice Research Institute Manila The Philippines

Elevated salinity imposes osmotic and ion toxicity stresses on living cells and requires a multitude of responses in order to enable plant survival. Building on earlier work profiling transcript levels in rice （Oryza sativa） shoots of FL478, a salt-tolerant indica recombinant inbred line, and IR29, a salt-sensitive cultivar, transcript levels were compared in roots of these two accessions as well as in the roots of two additional salt-tolerant indica genotypes, the landrace Pokkali and the recombinant inbred line IR63731. The aim of this study was to compare transcripts in the sensitive and the tolerant lines in order to identify genes likely to be involved in plant salinity tolerance, rather than in responses to salinity perse. Transcript profiles of several gene families with known links to salinity tolerance are described （e.g. HKTs, NHXs）. The putative function of a set of genes identified through their salt responsiveness, transcript levels, and/or chro- mosomal location （i.e. underneath QTLs for salinity tolerance） is also discussed. Finally, the parental origin of the Saltol region in FL478 is further investigated. Overall, the dataset presented appears to be robust and it seems likely that this system could provide a reliable strategy for the discovery of novel genes involved in salinity tolerance.

关键词： Rice root salinity tolerance microarray HKT Saltol.

Mobility of charge carriers in mineral oil and ester fluids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2021年第6期6卷 1040-1050页

作者： Qingj.ang Xue Igor Timoshkin mark PWilson Martin Given Scott j.MacGregor Department of Electronic and Electrical Engineering University of StrathclydeGlasgowUK

New,more stringent environmental requirements for electrical insulation liquids have led to the development of novel,more environment‐friendly liquid *** fluids,introduced several decades ago,provide a viable alternative to traditional mineral insu-lating *** order to expand the practical applications of these novel dielectric fluids,their dielectric and electrical parameters should be *** of the critical pa-rameters that affects and governs the development of pre‐breakdown processes in insulating liquids is the mobility of charge *** the present paper,the mobility of charge carriers in commercially available synthetic and natural insulating ester fluids and in a mineral insulating oil were obtained using two methods,the time of flight and the space charge saturation current *** mobility was obtained for a wide range of electrical field *** was found that the mobility of charge carriers is greater in the mineral oil than in both,the natural and synthetic,ester *** was also established that the mobility is higher for higher applied electric *** results of this work will help in characterizing liquid dielectrics and in optimizing high‐voltage systems in which liquid dielectrics,including natural and synthetic ester fluids,are used.

关键词： field. charge liquids

The Chapman-Richards Distribution and its Relationship to the Generalized Beta

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Forest Ecosystems 2019年第3期6卷 219-235页

作者： j.ffrey H.Gove Thomas B.Lynch mark j.Ducey USDA Forest Service Northern Research Station271 Mast Road Durham 03824NHUSA Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA Department of Natural Resources and the Environment University of New Hampshire114 James Hall Durham 03824NHUSA

Background: The Chapman-Richards distribution is developed as a special case of the equilibrium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distribution incorporates the vital rate assumptions of the Chapman-Richards growth function, constant mortality and recruitment into the mathematical form of the distribution. Therefore, unlike 'assumed' distribution models, it is intrinsically linked with the underlying vital rates for the forest area under consideration. Methods: It is shown that the Chapman-Richards distribution can be recast as a subset of the generalized beta distribution of the first kind, a rich family of assumed probability distribution models with known properties. These known properties for the generalized beta are then immediately available for the Chapman-Richards distribution, such as the form of the compatible basal area-size distribution. A simple two-stage procedure is proposed for the estimation of the model parameters and simulation experiments are conducted to validate the procedure for four different possible distribution shapes. Results: The simulations explore the efficacy of the two-stage estimation procedure;these cover the estimation of the growth equation and mortality-recruitment derives from the equilibrium assumption. The parameter estimates are shown to depend on both the sample size and the amount of noise imparted to the synthetic measurements. The results vary somewhat by distribution shape, with the smaller, noisier samples providing less reliable estimates of the vital rates and final distribution forms. Conclusions: The Chapman-Richards distribution in its original form, or recast as a generalized beta form, presents a potentially useful model integrating vital rates and stand diameters into a flexible family of resultant distributions shapes. The data requirements are modest, and parameter estimation is straightforward provided the minimal recommended sample sizes are obtained.

关键词： Diameter distributions Chapman-Richards growth Generalized beta distribution of the first kind Maximum likelihood McKendrick-Von Foerster equation Physiologically structured population model Size-structured distributions

j.j.noileal bypass:A surgery of the past and a review of its complications

在线全文

学校读者我要写书评

暂无评论

World j.urnal of Gastroenterology 2009年第18期15卷 2277-2279页

作者： Dushyant Singh Alexandra S Laya Wendell K Clarkston mark j.Allen Department of Gastroenterology and Hepatology University of Missouri Kansas CityKansas City MO 64111United States

j.j.noileal bypass(j.B),popular in the 1960s and 1970s,had remarkable success in achieving weight loss by creating a surgical short bowel *** patient had an unusual case of liver disease and provided no history of prior bariatric ***,it was recognized that he had a j.B in the 1970s,which was also responsible for the gamut of his *** with j.B are often not recognized,as they died of complications,or underwent reversal of their surgery or a liver-kidney *** identification with prompt reversal,and the recognition and treatment of the life-threatening consequences play a critical role in the management of such patients.

关键词： j.j.noileal bypass Bariatric surgery Weightloss Obesity Morbid obesity

Evolution of interventional endoscopic ultrasound

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Gastroenterology Report 2023年第1期11卷 131-139页

作者： mark j.Radlinski Daniel S.Strand Vanessa M.Shami Division of Gastroenterology and Hepatology University of VirginiaCharlottesvilleVAUSA

Endoscopic ultrasound(EUS)has become an indispensable modality for the assessment of the gastrointestinal tract and adj.cent structures since its origin in the *** the development of the linear echoendoscope,EUS has evolved from a purely diagnostic modality to a sophisticated tool for intervention,with numerous luminal,pancreaticobiliary,and hepatic ***,these applications may be subdivided into three categories:transluminal drainage or access procedures,inj.ction therapy,and EUS-guided liver *** drainage or access procedures include management of pancreatic fluid collection,EUS-guided biliary drainage,EUS-guided bile duct drainage,EUS-guided pancreatic duct drainage,and enteral anastomosis *** therapies include therapeutic EUS-guided inj.ctions for management of malignancies accessible by ***-guided liver applications include EUS-guided liver biopsy,EUS-guided portal pressure gradient measurement,and EUS-guided vascular *** this review,we discuss the origins of each of these EUS applications,evolution of techniques leading to the current status,and future directions of EUS-guided interventional therapy.

关键词： endoscopic ultrasound interventional endoscopic ultrasound biliary drainage gastroj.j.nostomy pancreatic pseudocyst drainage

Breeding wheat for drought tolerance： Progress and technologies

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 Integrative Agriculture 2016年第5期15卷 935-943页

作者： Learnmore Mwadzingeni Hussein Shimelis Ernest Dube mark D Laing Toi j.Tsilo College of Agriculture Engineering and Science University of KwaZulu-Natal/African Centre for Crop Improvement Scottsville 3209 South Africa Agricultural Research Council-Small Grain Institute (ARC-SGI) Bethlehem 9700 South Africa

Recurrent drought associated with climate change is among the principal constraints to global productivity of wheat（Triticum aestivum（L.） and T. turgidum（L.））. Numerous efforts to mitigate drought through breeding resilient varieties are underway across the world. Progress is, however, hampered because drought tolerance is a complex trait that is controlled by many genes and its full expression is affected by the environment. Furthermore, wheat has a structurally intricate and large genome. Consequently, breeding for drought tolerance requires the integration of various knowledge systems and methodologies from multiple disciplines in plant sciences. This review summarizes the progress made in dry land wheat improvement, advances in knowledge, complementary methodologies, and perspectives towards breeding for drought tolerance in the crop to create a coherent overview. Phenotypic, biochemical and genomics-assisted selection methodologies are discussed as leading research components used to exploit genetic variation. Advances in phenomic and genomic technologies are highlighted as options to circumvent existing bottlenecks in phenotypic and genomic selection, and gene transfer. The prospects of further integration of these technologies with other omics technologies are also provided.

关键词： drought tolerance genomic selection genotyping phenotyping wheat

Effect of Cooling Rate on the Room Temperature Microstructure Following the Intercritical Deformation of Steel S460

在线全文

学校读者我要写书评

暂无评论

j.urnal of Iron and Steel Research International 2011年第S1期18卷 500-505页

作者： Hinton j.hn S Palmiere Eric j.Rainforth W.mark IMMPETUS Dept.Of Materials Science and EngineeringThe University of SheffieldMappin StSheffieldSouth YorkshireS1 3JDUK

The effect of final hot rolling in the intercritical (α+γ) region on microstructure and properties is very specific to the individual processing conditions and the chemical composition of a steel.S460 is a plate steel processed in this *** reproduce at the laboratory scale,a multi-stage simulation was developed which included a high temperature austenite deformation and an isothermal *** effect of the applied cooling rate following intercritical deformation was *** 1K/s (typical industrial cooling) the microstructure was similar to the reference sample,but included an intragranular ferrite *** was due to differences in processing history,and considered to be linked to a larger prior austenite grain *** an accelerated cooling rate (15K/s),acicular ferrite formed on shear bands within the strained austenite *** scans have been completed to provide further information about the microstructures,with band contrast able to identify the pearlite phase at the slowest cooling *** is a starting point from which to focus on the ferrite morphologies.

关键词： intercritical deformation cooling rate laboratory simulation plate steel acicular ferrite