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Impact of direct and indirect heating systems in broiler units on environmental conditions and flock performance

Journal of Integrative Agriculture 2016年第11期15卷 2588-2595页

作者： Shaun smith Joseph Meade james Gibbons Kevina Mc Gill Declan Bolton Paul Whyte UCD School of Veterinary Medicine University College Dublin Belfield Dublin 4 Ireland Teagasc Ashtown Food Research Centre Ashtown Dublin 15 Ireland

This study compared the impact of three indirect heating systems to direct gas flame heaters on a selection of flock performance and environmental indicators in commercial broiler units. No statistically significant differences（P≥0.05） were found in flock mortality rates, bird weight, water consumption, stress response, carbon dioxide, ammonia, temperature, relative humidity, litter quality, within-flock Campylobacter levels or mean Campylobacter counts when flock data from any of the three indirect heating systems were compared to flocks reared in houses with direct heating systems. Differences in litter quality were observed between upper and lower litter layers in all houses, regardless of heating type, which may have implications for bird health and welfare. Carbon dioxide concentrations in houses with direct heating systems were significantly higher than those in houses with indirect heating systems during the first 10 days of bird life（P≤0.05）. This was due to the increased use of heating systems during this period of the flock cycle. Differences in CO2 concentrations had no effect on flock performance, possibly due to the fact that concentrations did not exceed known safe levels. A statistically significant increase in stress response was observed in birds as a result of partial depopulation（thinning） within houses, irrespective of heating system type used（P≤0.05）. Stress associated with thinning may have consequences for bird welfare and food safety. In conclusion, the results of our study suggest that indirect heating systems do not appear to negatively impact on flock performance, stress response, within-flock Campylobacter levels or mean Campylobacter counts and do not appear to significantly alter environmental conditions within broiler houses when compared to houses equipped with direct heating systems. Indirect systems are a viable alternative for heating broiler houses in terms of flock performance, bird welfare and food safety.

关键词： litter quality welfare stress poultry production campylobacter environmental conditions

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Improving estimates of waning immunity rates in stochastic SIRS models with a hierarchical framework

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Infectious Disease Modelling 2023年第4期8卷 1127-1137页

作者： Punya Alahakoon james M.McCaw peter GTaylor School of Mathematics and Statistics The University of MelbourneMelbourneAustralia Centre for Epidemiology and Biostatistics Melbourne School of Population and Global HealthThe University of MelbourneMelbourneAustralia School of Population Health University of New South WalesSydneyAustralia Kirby Institute University of New South WalesSydneyAustralia

As most disease causing pathogens require transmission from an infectious individual to a susceptible individual,continued persistence of the pathogen within the population requires the replenishment of susceptibles through births,immigration,or waning *** the introduction of an unknown infectious disease into a fully susceptible population where it is not known how long immunity is conferred once an individual recovers from ***,initially,the prevalence of disease increases(that is,the infection takes off),the number of infectives will usually decrease to a low level after the first major *** this post-outbreak period,the disease dynamics may be influenced by stochastic effects and there is a non-zero probability that the epidemic will die *** out in this period following the first major outbreak is known as an epidemic *** the disease does not die out,the susceptible population may be replenished by the waning of immunity,and a second wave may *** this study,we investigate if the rate of waning immunity(and other epidemiological parameters)can be reliably estimated from multiple outbreak data,in which some outbreaks display epidemic fade-out and others do *** generated synthetic outbreak data from independent simulations of stochastic SIRS models in multiple *** outbreaks faded-out and some did *** conducted Bayesian parameter estimation under two alternative approaches:independently on each outbreak and under a hierarchical *** conducting independent estimation,the waning immunity rate was poorly estimated and biased towards zero when an epidemic fade-out was ***,under a hierarchical approach,we obtained more accurate and precise posterior estimates for the rate of waning immunity and other epidemiological *** greatest improvement in estimates was obtained for those communities in which epidemic fade-out was observed.

关键词： estimates stochastic estimation

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Arsenic uptake by arbuscular mycorrhizal maize (Zea mays L.) grown in an arsenic-contaminated soil with added phosphorus

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Journal of Environmental Sciences 2007年第10期19卷 1245-1251页

作者： XIA Yun-sheng CHEN Bao-dong CHRISTIE peter smith F Andrew WANG You-shan LI Xiao-lin College of Resources and Environmental Sciences China Agricultural University Beijing 100094 China Department of Soil Environmental Science Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beifing 100085 China Agricultural and Environmental Science Department Queen＇s University Belfast Belfast BT9 5PX UK Soil and Land Systems School of Earth and Environmental Sciences Waite Campus The University of Adelaide South Australia 5005 Australia Institute of Plant Nutrition and resources Beijing Municiple Academy of Agriculture and Forestry Sciences Belting 100097 China

The effects of arbuscular mycorrhizal （AM） fungus （Glomus mosseae） and phosphorus （P） addition （100 mg/kg soil） on arsenic （As） uptake by maize plants （Zea mays L.） from an As-contaminated soil were examined in a glasshouse experiment. Non-mycorrhizal and zero-P addition controls were included. Plant biomass and concentrations and uptake of As, P, and other nutrients, AM colonization, root lengths, and hyphal length densities were determined. The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium. Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments, but shoot and root biomass of AM plants was depressed by P application. AM fungal inoculation decreased shoot As concentrations when no P was added, and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition, respectively. Shoot and root uptake of P, Mn, Cu, and Zn increased, but shoot Fe uptake decreased by 44.6%, with inoculation, when P was added. P addition reduced shoot P, Fe, Mn, Cu, and Zn uptake of AM plants, but increased root Fe and Mn uptake of the nonmycorrhizal ones. AM colonization therefore appeared to enhance plant tolerance to As in low P soil, and have some potential for the phytostabilization of As-contaminated soil, however, P application may introduce additional environmental risk by increasing soil As mobility.

关键词： arsenic arbuscular mycorrhiza phosphate maize phytostabilization

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Optimization of operational strategies for rich gas enhanced oil recovery based on a pilot test in the Bakken tight oil reservoir

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Petroleum Science 2023年第5期20卷 2921-2938页

作者： Xincheng Wan Lu Jin Nicholas A.Azzolina Jin Zhao Xue Yu Steven A.smith james A.Sorensen Energy&Environmental Research Center University of North Dakota15 North 23rd StreetStop 9018Grand ForksND58202-9018USA

Horizontal well drilling and multistage hydraulic fracturing have been demonstrated as effective approaches for stimulating oil production in the Bakken tight oil ***,after multiple years of production,primary oil recovery in the Bakken is generally less than 10%of the estimated original oil in *** huff‘n’puff(HnP)has been tested in the Bakken Formation as an enhanced oil recovery(EOR)method;however,most field pilot test results showed no significant incremental oil *** of the factors affecting HnP EOR performance is premature gas breakthrough,which is one of the most critical issues observed in the field because of the presence of interwell ***,injected gas rapidly reaches adjacent production wells without contacting reservoir rock and increasing oil *** conformance control is therefore needed to avoid early gas breakthrough and improve EOR *** this study,a rich gas EOR pilot in the Bakken was carefully analyzed to collect the essential reservoir and operational data.A simulation model with 16 wells was then developed to reproduce the production history and predict the EOR performance with and without conformance *** operational strategies,including single-and multiple-well HnP,with different gas injection constraints were *** simulation results of single-well HnP without conformance control showed that a rich gas injection rate of at least 10 MMscfd was needed to yield meaningful incremental oil *** strategy of conformance control via water injection could significantly improve oil production in the HnP well,but injecting an excessive amount of water also leads to water breakthrough and loss of oil production in the offset *** analyzing the production performance of the wells individually,the arrangement of wells was optimized for multiple-well HnP *** multiwell results showed that rich gas EOR could improve oil production up to 7.4%by employing confor

关键词： Rich gas injection Bakken tight oil reservoir EOR strategies Conformance control Embedded discrete fracture model

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Minimal volume vitrification of epididymal spermatozoa results in successful in vitro fertilization and embryo development in mice

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Asian Journal of Andrology 2017年第1期19卷 107-112页

作者： Fabrizzio Horta Hamida Alzobi Sutthipat Jitanantawittaya Sally Catt Penny Chen Mulyoto Pangestu peter Temple-smith Education Program in Reproduction and Development Department Obstetrics and Gynaecology Monash University Clayton VlC 3168 Australia Department of Obstetrics and Gynaecology Unit of Reproductive Medicine Clinica Las Condes Lo Fentecilla 441 Las Condes Santiago Region Metropolitana 7550000 Chile.

This study compared three cryopreservation protocols on sperm functions, IVF outcomes, and embryo development. Epididymal spermatozoa cryopreserved using slow-cooling （18% w/v raffinose, RS-C） were compared with spermatozoa vitrified using 0.25 M sucrose （SV） or 18% w/v raffinose （RV）. The motility, vitality, and DNA damage （TUNEL assay） of fresh control （FC） spermatozoa were compared with post-thawed or warmed RS-C, RV, and SV samples. Mouse oocytes （n = 267） were randomly assigned into three groups for insemination： RV （n = 102）, RS-C （n = 86）, and FC （n = 79）. The number and the proportion of two-cell embryos and blastocysts from each treatment were assessed. Sperm motility （P 〈 0.01） and vitality （P 〈 0.05） were significantly reduced after vitrification compared with slow-cooled spermatozoa. However, DNA fragmentation was significantly reduced in spermatozoa vitrified using sucrose （15 - 1.8% [SV] vs 26 - 2.8% [RV] and 27 - 1.2% [RS-C]; P 〈 0.01）. Although the number of two-cell embryos produced by RS-C, RV, and FC spermatozoa was not significantly different, the number of blastocysts produced from two-cell embryos using RV spermatozoa was significantly higher than FC spermatozoa （P = 0.0053）. This simple, small volume vitrification protocol and standard insemination method allows successful embryo production from small numbers of epididymal spermatozoa and may be applied clinically to circumvent the need for ICSI, which has the disadvantage of bypassing sperm selection.

关键词： cryopreservation epididymal sperm in vitro fertilization/intracytoplasmic sperm injection reproductive techniques sperm DNA damage vitrification

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Drying characteristics and quality of bananas under infrared radiation heating

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International Journal of Agricultural and Biological Engineering 2013年第3期6卷 58-70页

作者： Milly A.Pekke Zhongli Pan Griffiths G.Atungulu Gary smith james F.Thompson Department of Food Science and Technology University of California DavisDavisCA 95616USA Processed Foods Research Unit USDA-ARS Western Regional Research CenterAlbanyCA 94710USA Department of Biological and Agricultural Engineering University of California DavisDavisCA 95616USA Department of Food Science University of ArkansasFayettevilleAR 72704USA

Hot air(HA)drying of banana has low drying efficiency and results in undesirable product *** objectives of this research were to investigate the feasibility of infrared(IR)heating to improve banana drying rate,evaluate quality of the dried product,and establish models for predicting drying *** slices of 5 mm and 8 mm thickness were dried with IR and HA at product temperatures of 60℃,70℃ and 80℃.Banana drying characteristics and changes in residual polyphenol oxidase(PPO),Hydroxymethylfurfural(HMF),color,moisture content(MC)and water activity during the treatments were *** showed that significant moisture reduction and higher drying rates were achieved with IR drying compared to HA drying in the early *** drying data could be fitted to the Page model for accurate prediction of MC change for IR and HA drying with mean R2 of *** was noted that enzyme inactivation occurred more quickly with IR than with HA drying.A unique response of PPO under IR and HA drying was *** heating of banana inactivated PPO within the first 20 min of drying at 60℃,70℃ and 80℃,while PPO was first activated before inactivation at 60℃ and 70℃ drying with *** highest HMF content occurred in banana slices with 5 mm thickness dried with IR at a product temperature of 80℃.It is therefore recommendable to dry banana with IR at product temperature of 70℃ or below to preserve the product *** findings are new and provide more insight in the application of IR heating for drying banana for improved drying rate and product quality.

关键词： drying banana infrared radiation hot air drying enzyme inactivation

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Competitive interactions and coexistence of sympatric flagship carnivores in Asia

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Integrative Zoology 2024年第2期19卷 183-199页

作者： Zhilin LI Jiayu LU Xiaoyi SHI Li’an DUO james L.D.smith Tianming WANG Tianjin Key Laboratory of Conservation and Utilization of Animal Diversity College of Life SciencesTianjin Normal UniversityTianjinChina Department of Fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Ministry of Education Key Laboratory for Biodiversity Science and Engineering College of Life SciencesBeijing Normal UniversityBeijingChina National Forestry and Grassland Administration Key Laboratory for Conservation Ecology of Northeast Tiger and Leopard BeijingChina

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore *** studies exploring the dynamics and competition between tigers(Panthera tigris)and leopards(***)span decades,there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale,as well as the drivers determining their exploitative and interference *** gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models;we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and *** and ungulate density were the most important predictors in regulating the coexistence *** and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial *** addition,they showed a higher dietary overlap in the prey-rich *** determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation ***,studies with multiple metrics would promote the detection of interference *** study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad ***-makers and managers should pay more attention to the factors of elevation,prey abundance,and habitat structures for the conservation of tigers and leopards.

关键词： carnivores coexistence mechanisms competitive interactions exploitative competition interference competition

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活性污泥法污水处理虚拟设备

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中国给水排水 2001年第9期17卷 17-22页

作者：蔡建安 james A.smith 安徽工业大学环境工程系安徽马鞍山243002 Dept. of Civil Engineering University of Virginia Charlottesville

在LabVIEW平台上开发的活性污泥法污水处理虚拟设备 ,以反应动力学为基础构造基本模块 ,通过连线来组合或改变工艺流程。虚拟设备采用循环结构 ,迭代运行 ,能解决具有交互作用的多控制底物问题。虚拟设备的控制界面模拟传统的控制仪表 ... 详细信息

在LabVIEW平台上开发的活性污泥法污水处理虚拟设备 ,以反应动力学为基础构造基本模块 ,通过连线来组合或改变工艺流程。虚拟设备采用循环结构 ,迭代运行 ,能解决具有交互作用的多控制底物问题。虚拟设备的控制界面模拟传统的控制仪表 ,仿真运行 ,其工艺、环境和设备参数可直接选择 ,以“所见即所得”的可视技术获得动态的结果 ,节约了试验研究的时间和经费 ,提高了设计的可靠性 ,也能在已建成的水处理设施上进行控制和预报。

关键词：污水处理活性污泥法虚拟设备

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Novel strategies for managing pancreatic cancer

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World Journal of Gastroenterology 2014年第40期20卷 14717-14725页

作者： Welley S Loc Jill P smith Gail Matters Mark Kester james H Adair Department of Chemistry The Pennsylvania State University University Park PA 16802 United States National Institute of Diabetes and Digestive and Kidney Disease The National Institutes of Health Bethesda MD 20892 United States Department of Medicine The Pennsylvania State University College of Medicine Hershey PA 17033 United States Department of Biochemistry and Molecular Biology The Pennsylvania State University College of MedicineHershey PA 17033 United States Department of Pharmacology ThePennsylvania State University College of Medicine Hershey PA17033 United States Departments of Materials Science and Engineering and Bioengineering The Pennsylvania State University University Park PA 16802 United States

With the incidence reports of pancreatic cancer increasing every year,research over the last several decades has been focused on the means to achieve early diagnosis in patients that are at a high risk of developing the *** review covers current strategies for managing pancreatic cancer and further discusses efforts in understanding the role of early onset symp-toms leading to tumor *** investigations in this discussion include type 3c diabetes,selected biomarkers and pathways related to pancreatic intraepithelial neoplasia lesions,drug resistance,and advances in nanomedicine which may provide significant solutions for improving early detection and treatments in future medicine.

关键词： Pancreatic cancer Diagnosis Treatment Signaling pathways Nanomedicine Biomarkers

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Resection of isolated liver oligometastatic disease in pancreatic ductal adenocarcinoma:Is there a survival benefit?A systematic review

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World Journal of Gastrointestinal Surgery 2023年第7期15卷 1512-1521页

作者： james M Halle-smith Sarah Powell-Brett Keith Roberts Nikolaos A Chatzizacharias Department of HPB and Liver Transplant Queen Elizabeth HospitalUniversity of BirminghamBirmingham B152GWUnited Kingdom

BACKGROUND Presence of liver metastatic disease in pancreatic ductal adenocarcinoma(PDAC),either synchronous or metachronous after pancreatic resection,is a terminal diagnosis that warrants management with palliative intent as per all international practice ***,there is an increasing interest on any potential value of surgical treatment of isolated oligometastatic disease in selected *** To present the published evidence on surgical management of PDAC liver metastases,synchronous and metachronous,and compare the outcomes of these treatments to the current standard of *** A systematic review was performed in line with the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines to compare the outcomes of both synchronous and metachronous liver metastases resection to standard *** 356 studies were identified,31 studies underwent full-text review and of these 10 were suitable for *** synchronous resection of liver metastases was compared to standard care,most studies did not demonstrate a survival benefit with the exception of one study that utilised neoadjuvant ***,resection of metachronous disease appeared to confer a survival advantage when compared to treatment with chemotherapy *** A survival benefit may exist in resection of selected cases of metachronous liver oligometastatic PDAC disease,after disease biology has been tested with time and systemic *** survival benefit is less clear in synchronous cases;however an approach with neoadjuvant treatment and consideration of resection in some selected cases may confer some *** studies should focus on pathways for selection of cases that may benefit from an aggressive approach.

关键词： Pancreas cancer Liver metastases Surgical resection Systematic review

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