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Animal models of genetic causes of male infertility

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Asian Journal of Andrology 2002年第3期4卷 213-219页

作者： greg L. Christensen Douglas T. Carrell Andrology Department University of Utah School of Medicine Salt Lake City Utah 84132 USAAndrology Department University of Utah School of Medicine Salt Lake City Utah 84132 USA

Introduction In the past 10 years, more than 100 different genetically engineered mice have been developed with an abnormality in spermatogenesis. More than half of these male infertility animal models have been reported in the past three years alone. Spermatogenic defects in these models vary considerably, ranging from the inappropriate migration of primordial germ cells to the inability of mature spermatozoa to bind the zona pellucida. Many of

关键词： animal models genes genetics knockout male infertility

Roles of SO_2 oxidation in new particle formation events

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Journal of Environmental Sciences 2015年第4期27卷 90-101页

作者： He Meng Yujiao Zhu greg J.Evans Cheol-Heon Jeong Xiaohong Yao Key Lab of Marine Environmental Science and Ecology Ministry of Education Ocean University of China Southern Ontario Centre for Atmospheric Aerosol Research University of Toronto

The oxidation of SO2 is commonly regarded as a major driver for new particle formation（NPF） in the atmosphere. In this study, we explored the connection between measured mixing ratio of SO2 and observed long-term（duration 〉 3 hr） and short-term（duration〈 1.5 hr） NPF events at a semi-urban site in Toronto. Apparent NPF rates（J30） showed a moderate correlation with the concentration of sulfuric acid（[H2SO4]） calculated from the measured mixing ratio of SO2 in long-term NPF events and some short-term NPF events（Category I）（R^2= 0.66）. The exponent in the fitting line of J30~ [H2SO4]nin these events was1.6. It was also found that SO2 mixing ratios varied a lot during long-term NPF events,leading to a significant variation of new particle counts. In the SO2-unexplained short-term NPF events（Category II）, analysis showed that new particles were formed aloft and then mixed down to the ground level. Further calculation results showed that sulfuric acid oxidized from SO2 probably made a negligible contribution to the growth of 〉 10 nm new particles.

关键词： Nucleation Particle growth Sulfuric acid Photochemical oxidation SO2

The role of lactose in weanling pig nutrition:a literature and meta-analysis review

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Journal of Animal Science and Biotechnology 2021年第2期12卷 462-478页

作者： Jinbiao Zhao Zeyu Zhang Shuai Zhang greg Page Neil W.Jaworski State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityNo.2 Yuanmingyuan West RoadBeijing 100193China Trouw Nutrition Innovation Stationsstraat 773800AG AmersfoortNetherlands

Lactose plays a crucial role in the growth performance of pigs at weaning because it is a palatable and easily digestible energy source that eases the transition from milk to solid ***,the digestibility of lactose declines after weaning due to a reduction in endogenous lactase activity in *** a result,some lactose may be fermented in the gastrointestinal tract of *** of lactose by intestinal microbiota yields lactic acid and volatile fatty acids,which may positively regulate the intestinal environment and microbiome,resulting in improved gastrointestinal health of weanling *** hypothesize that the prebiotic effect of lactose may play a larger role in weanling pig nutrition as the global feed industry strives to reduce antibiotic usage and pharmacological levels of zinc oxide and supra-nutritional levels of *** presented in this review indicates that high dietary lactose improves growth performance of piglets,as well as the growth of beneficial bacteria,particularly Lactobacillus,with the positive effects being more pronounced in the first 2 weeks after ***,the risk of post-weaning diarrhea may increase as pigs get older due to reduced lactase activity,high dietary lactose concentrations,and larger feed intakes,all of which may lead to excessive lactose fermentation in the intestine of the ***,dietary lactose levels exert different effects on growth performance and gastrointestinal physiological functions in different feeding phases of weanling ***,no formal recommendation of lactose for weanling pigs has been reported.A meta-analysis approach was used to determine that diets fed to swine should include 20%,15%,and 0 lactose from d 0-7,d 7-14,and d 14-35 post-weaning,***,sustainable swine production demands that economics must also be taken into account as lactose and lactose containing ingredients are ***,alternatives to lactose,so called“lactose equivalents

关键词： Growth performance Gut health Gut microbiota Lactose Lactose equivalents Weanling pig

Approximating Nonlinear Relations Between Susceptibility and Magnetic Contents in Rocks Using Neural Networks

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Tsinghua Science and Technology 2010年第3期15卷 281-287页

作者： William W Guo Michael Li Zhengxiang Li greg Whymark Faculty of Arts Business lnformatics and Education Central Queensland University Rockhampton QLD 4701 Australia The Institute for Geoscience Research (TIGER) Curtin University of Technology Perth WA 6845 Australia

Correlations between magnetic susceptibility and contents of magnetic minerals in rocks are important in interpreting magnetic anomalies in geophysical exploration and understanding magnetic behaviors of rocks in rock magnetism studies. Previous studies were focused on describing such correlations using a sole expression or a set of expressions through statistical analysis. In this paper, we use neural network techniques to approximate the nonlinear relations between susceptibility and magnetite and/or hematite contents in rocks. This is the first time that neural networks are used for such study in rock magnetism and magnetic petrophysics. Three multilayer perceptrons are trained for producing the best possible estimation on susceptibility based on magnetic contents. These trained models are capable of producing accurate mappings between susceptibility and magnetite and/or hematite contents in rocks. This approach opens a new way of quantitative simulation using neural networks in rock magnetism and petrophysical research and applications.

关键词： neural networks nonlinear function approximation rock magnetism magnetic susceptibility magnetic contents

Hip hemi-arthroplasty for neck of femur fracture:What is the current evidence?

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World Journal of Orthopedics 2018年第11期9卷 235-244页

作者： greg AJ Robertson Alexander M Wood Edinburgh Orthopaedic Trauma Unit Royal Infirmary of Edinburgh Orthopaedic Department Leeds General Infirmary

This editorial reviews and summarises the current evidence(meta-analyses and Cochrane reviews) relating to the use of hip hemi-arthroplasty for neck of femur fractures. Regarding the optimal surgical approach,two recent meta-analyses have found that posterior approaches are associated with: higher rates of dislocation compared to lateral and anterior approaches; and higher rates of re-operation compared to lateral approaches. Posterior approaches should therefore be avoided when performing hip hemi-arthroplasty procedures. Assessing the optimal prosthesis head component,three recent meta-analyses and one Cochrane review have found that while unipolar hemiarthroplasty can be associated with increased rates of acetabular erosion at short-term follow-up(up to 1 year),there is no significant difference between the unipolar hemi-arthroplasty and bipolar hemi-arthroplasty for surgical outcome,complication profile,functional outcome and acetabular erosion rates at longer-term follow-up(2 to 4 years). With bipolar hemi-arthroplasty being the more expensive prosthesis,unipolar hemi-arthroplasty is the recommended option. With regards to the optimal femoral stem insertion technique,three recent metaanalyses and one Cochrane Review have found that,while cemented hip hemi-arthroplasties are associated with a longer operative time compared to uncemented Hip Hemi-arthroplasties,cemented prostheses have lower rates of implant-related complications(particularly peri-prosthetic femoral fracture) and improved postoperative outcome regarding residual thigh pain and mobility. With no significant difference found between the two techniques for medical complications and mortality,cemented hip hemi-arthroplasty would appear to be the superior technique. On the topic of wound closure,one recent meta-analysis has found that,while staples can result in a quicker closure time,there is no significant difference in post-operative infections rates or wound healing outcomes when comparing staples

关键词： Hemi-arthroplasty Prosthesis Stem Head Hip Femoral Neck Fracture Cement

Lower limb stress fractures in sport:Optimising their management and outcome

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World Journal of Orthopedics 2017年第3期8卷 242-255页

作者： greg A J Robertson Alexander M Wood Edinburgh Orthopaedic Trauma Unit Royal Infirmary of Edinburgh Edinburgh Department of Orthopaedic Leeds General Infirmary

Stress fractures in sport are becoming increasing more common,comprising up to 10%of all of sporting *** 90%of such injuries are located in the lower *** articles aims to define the optimal management of lower limb stress fractures in the athlete,with a view to maximise return rates and minimise return times to *** planning of this condition is specific to the location of the ***,there remains a clear division of stress fractures by"high"and"low"risk."Low risk"stress fractures are those with a low probability of fracture propagation,delayed union,or non-union,and so can be managed reliably with rest and exercise *** include stress fractures of the PosteroMedial Tibial Diaphysis,Metatarsal Shafts,Distal Fibula,Medial Femoral Neck,Femoral Shaft and Calcaneus."High risk"stress fractures,in contrast,have increased rates of fracture propagation,displacement,delayed and non-union,and so require immediate cessation of activity,with orthopaedic referral,to assess the need for surgical *** include stress fractures of the Anterior Tibial Diaphysis,Fifth Metatarsal Base,Medial Malleolus,Lateral Femoral Neck,Tarsal Navicular and Great Toe *** order to establish the optimal methods for managing these injuries,we present and review the current evidence which guides the treatment of stress fractures in *** this,we note an increased role for surgical management of certain high risk stress fractures to improve return times and rates to *** this,key recommendations are provided for the management of the common stress fracture types seen in the *** case reports are also presented to illustrate the application of sportfocussed lower limb stress fracture treatment in the clinical setting.

关键词： Fractures Lower Limb Sport Management Stress

An empirical movement model for sixgill sharks in Puget Sound： Combining observed and unobserved behavior

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Current Zoology 2012年第1期58卷 103-115页

作者： Levin, Phillip S. Horne, Peter Andrews, Kelly S. Williams, greg Northwest Fisheries Science Center 2725 Montlake Blvd E Seattle WA 98112 USA

Understanding the movement of animals is fundamental to population and community ecology. Historically, it has been difficult to quantify movement patterns of most fishes, but technological advances in acoustic telemetry have increased our abilities to monitor their movement. In this study, we combined small-scale active acoustic tracking with large-scale passive acoustic monitoring to develop an empirical movement model for sixgill sharks in Puget Sound, WA, USA. We began by testing whether a correlated random walk model described the daily movement of sixgills; however, the model failed to capture home-ranging behavior. We added this behavior and used the resultant model (a biased random walk model) to determine whether daily movement patterns are able to explain large-scale seasonal movement. The daily model did not explain the larger-scale patterns of movement observed in the passive monitoring data. In order to create the large-scale patterns, sixgills must have performed behaviors (large, fast directed movements) that were unobserved during small-scale active tracking. In addition, seasonal shifts in location were not captured by the daily model. We added these ‘unobserved’ behaviors to the model and were able to capture large-scale seasonal movement of sixgill sharks over 150 days. The development of empirical models of movement allows researchers to develop hypotheses and test mechanisms responsible for a species movement behavior and spatial distribution. This knowledge will increase our ability to successfully manage species of concern.

关键词：运动模型行为模式跟踪观测鲨鱼海湾季节性变化声学监测运动模式

Assessing the readability of online information about jones fracture

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World Journal of Methodology 2023年第5期13卷 439-445页

作者： Khaled Farid Khaled Al-Kharouf Faisal Idrees Khan greg AJ Robertson Orthopaedic Surgery Portsmouth Hospitals UniversityPortsmouth PO63 LYUnited Kingdom Internal Medicine Tunbridge Wells HospitalTunbridge Wells E105NJUnited Kingdom Orthopaedic Surgery Queen Alexandra HospitalPortsmouth PO63LYUnited Kingdom

BACKGROUND Hand in hand with technological advancements,treatment modalities continue to *** the turn of the century,the internet has become the number one source of information for almost every ***,many patients look toward the internet as their primary source of information to learn about their respective medical *** American Medical Association and National Institute of Health strongly recommend that online medical information be written at the 6th to 8th-grade level to aid comprehension by patients of all literacy *** To assess the readability of online information regarding Jones *** hypothesis is that the reading level of medical information published on websites far exceeds the recommended reading level of 6th-8th grade as proposed by the American Medical Associate and National Institute of *** result of this study can help us formulate improved recommendations for publishing more comprehensible material and,thus,eventually improve patient compliance and clinical *** The exact phrase“Jones fracture”was queried on the three most common search engines,Google,Yahoo!,and Bing,on December 28,*** of December 2022,Google held 84%,Bing held 9%,and Yahoo!held 2%of the worldwide search engine market *** pages uniform resource locator from the first three pages of search results were recorded from each search *** web pages were classified according to academic,physician-sponsored,governmental and non-government organizations(NGO),commercial,and unspecified as per formally defined *** associated with an educational institution or medical organization were classified as *** with products for sale,corporate sponsorship,or advertisements were classified as *** websites or NGOs comprised those that received government subsidies or *** that were independently owned by physicians or physician groups were respectively classed as physi

关键词： Jones fracture Jones fracture treatment Jones fracture management Jones fracture prevention Jones fracture types Jones fracture location

Sensitivity Analysis,Determination and Optimization of Granite RHT Parameters

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Journal of Beijing Institute of Technology 2019年第1期28卷 94-102页

作者： Hongchao Li Yong Chen Dianshu Liu Lei Zhao greg You City College Kunming University of Science and Technology School of Mechanics &Civil Engineering China University of Mining and Technology(Beijing) Faculty of Science and Technology Federation University Australia

The RHT model has 34 parameters,among which 19 parameters can be obtained by experiments or theoretical calculations and the remaining 15 parameters are difficult to *** this study,firstly,10 Hopkinson impact tests were conducted to acquire the typical stress-strain curves of granite under dynamic *** the sensitivity analysis,it is found that 13 of the 15 difficult-acquired parameters are effective to affect the shape of the stress-strain curve,and the other two parameters have no *** the initial determination of model parameters with reference to the concrete RHT model,a new approach is proposed to optimize the 13 influential parameters through the LS-DYNA numerical simulation and orthogonal ***,the determined granite RHT model parameters are verified by the results of Hopkinson impact tests conducted in this study and the bullet penetration test by Wang et *** results of the numerical simulations are in a good agreement with the tested results,which validates the suitability of the proposed method to acquire RHT model parameters for granite and the other rocks.

关键词： RHT model sensitivity analysis SHPB orthogonal experiment