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Sperm cryodamage occurs after rapid freezing phase:flow cytometry approach and antioxidant enzymes activity at different stages of cryopreservation

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Journal of Animal science and Biotechnology 2016年第4期7卷 495-503页

作者： L.S.Castro T.R.S.Hamilton C.M.Mendes M.Nichi V.H.Barnabe J.A.Visintin M.E.O.A.Assumpcao laboratory of spermatozoa biology department of animal reproductionschool of veterinary medicine and animal scienceuniversity of sao pauloBrazil laboratory of in vitro fertilization cloning and animal transgenesisdepartment of animal reproductionschool of veterinary medicine and animal scienceuniversity of sao paulosao pauloBrazil laboratory of andrology.department of animal reproduction school of veterinary medicine and animal scienceuniversity of sao paulosao pauloBrazil

Background： In order to improve the efficiency of bovine sperm cryopreservation process, it is important to understand how spermatozoa respond to differences in temperature as well as the ability to recover its own metabolism. The combination between flow cytometry approach and antioxidant enzymes activity allows a more sensible evaluation of sperm cell during cryopreservation. The aim of this study was to evaluate sperm attributes and antioxidant enzymes activity during different stages of cryopreservation process. Semen samples from Holstein bulls （n = 4） were separated in 3 treatments： fresh （37 ℃）; cooled （5 ℃）; and thawed. Evaluation occurred at 0 h and 2 h after incubation. Membrane integrity, mitochondrial membrane potential （MMP） and DNA damages were evaluated by flow cytometry; activities of antioxidant enzymes such as catalase, superoxide dismutase and gluthatione peroxidase were measured by spectrofotometry. Results： There was an increase in the percentage of sperm with DNA damage in the thawed group, compared to fresh and cooled, and for 2 hs of incubation when compared to 0 h. Considering MMP, there was an increase in the percentage of cells with medium potential in thawed group when compared to fresh and cooled groups. Opposingly, a decrease was observed in the thawed group considering high mitochondrial potential. Also in the thawed group, there was an increase on cells with damaged acrosome and membrane when compared to fresh and cooled groups. Significant correlations were found between antioxidant enzymes activity and membrane or mitochondrial parameters. Conclusion： Based on our results, we conclude that cryopreservation affects cellular and DNA integrity and that the critical moment is when sperm cells are exposed to freezing temperature. Also, our study indicates that intracellular antioxidant machinery （SOD and GPX enzymes） is not enough to control cryodamage.

关键词： Bovine DNA integrity JC-1 Sperm viability

Intelligent predictive maintenance for fault diagnosis and prognosis in machine centers： Industry 4.0 scenario

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Advances in Manufacturing 2017年第4期5卷 377-387页

作者： Zhe Li Yi Wang Ke-Sheng Wang Department of Mechanical and Industrial Engineering Norwegian University of Science and TechnologyTrondheim Norway school of Business Plymouth University Plymouth UK

Fault diagnosis and prognosis in mechanical systems have been researched and developed in the last few decades at a very rapid rate. However, owing to the high complexity of machine centers, research on improving the accuracy and reliability of fault diagnosis and prognosis via data mining remains a prominent issue in this field. This study investigates fault diagnosis and prognosis in machine centers based on data mining approaches to formulate a systematic approach and obtain knowledge for predictive maintenance in Industry 4.0 era. We introduce a system framework based on Industry 4.0 concepts, which includes the process of fault analysis and treatment for predictive maintenance in machine centers. The framework includes five modules： sensor selection and data acquisition module, data preprocessing module, data mining module, decision support module, and maintenance implementation module. Furthermore, a case study is presented to illustrate the application of the data mining methods for fault diagnosis and prognosis in machine centers as an Industry 4.0 scenario.

关键词： Data mining (DM) Machine centers Predictive maintenance Industry 4.0

Copper Adsorption on Olivine

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 237-241页

作者： Lei Shao, Rolf A. Kleiv, Kunt L. Sandvik, Cunyi Song, Shouci Lu ( Resources Engineering school, University of science and Technology Beijing, Beijing 100083, China Department of Geology and Mineral Resources Engineering, norwegian University of science a Resources Engineering school University of Science and Technology Beijing Beijing 100083 China Department of Geology and Mineral Resources Engineering Norwegian University of Science and Technology 7034 Trondheim Norway

Copper adsorption on olivine supplied by the A/S Olivine Production Plant at Aheim in western Norway was studied. The factors were evaluated which affect the uptake of copper. It is shown that the equilibrium pH of aqueous solution has the greatest influence on copper adsorption thanks to the competitive adsorption between proton and copper ions, and the adsorption of copper to olivine increases rapidly with pH increasing from 4 to 6. Moreover, initial copper concentration and olivine dose possess significant effect on copper adsorption, for the adsorption rate of copper increases with olivine dose increasing or initial copper concentration decreasing at the same pH. In addition, the ionic strength effect on the adsorption was also investigated, but it owns little effect on the adsorption process of copper due to the formation of inner sphere adsorption of copper on olivine. The experimental data show that olivine has a high acid buffer capacity and is an effective adsorbent for copper.

关键词： copper adsorption olivine, ionic strength acid mine drainage

A review of tuberculosis at the wildlife-livestock-human interface in Zambia

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Infectious Diseases of Poverty 2013年第1期2卷 100-104页

作者： Sydney Malama John Bwalya Muma Jacques Godfroid Institute of Economic and Social Research University of ZambiaPO Box 30900LusakaZambia Department of Disease Control School of Veterinary MedicineUniversity of ZambiaPO Box 32379LusakaZambia Department of Food Safety and Infection Biology Section Biostatistics and EpidemiologyNorwegian School of Veterinary ScienceUllevalsveien 72OsloNorway

Zambia’s estimated incidence of all forms of human tuberculosis(TB)is 707/100,*** prevalence of bovine tuberculosis(BTB)-infection with Mycobacterium bovis-in cattle and the Kafue lechwe antelopes(Kobus leche Kafuensis)has been reported in the Kafue *** of unpasteurised milk and meat products from infected animals poses a risk of transmitting zoonotic tuberculosis to people living at the human-animal *** the reported high prevalence of BTB in both livestock and wildlife,information on the proportion of human patients infected with *** is unknown in *** paper reviews the available information in English on human,livestock and wildlife TB in Zambia with the purpose of assessing the burden of animal infections with *** complex and its public health implications.

关键词： Bovine tuberculosis Kafue lechwe Interface Zoonotic tuberculosis

Oblique Wave-Induced Responses of A VLFS Edged with A Pair of Inclined Perforated Plates

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China Ocean Engineering 2018年第1期32卷 14-25页

作者： CHENG Yong JI Chun-yan ZHAI Gang-jun Gaidai Oleg school of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Deepwater Engineering Research Center Dalian University of Technology Centre for Ships and Ocean Structures Norwegian University of Science and Technology

This paper is concerned with the hydroelastic responses of a mat-like, rectangular very large floating structure(VLFS) edged with a pair of horizontal/inclined perforated anti-motion plates in the context of the direct coupling method. The updated Lagrangian formulae are applied to establish the equilibrium equations of the VLFS and the total potential formula is employed for fluids in the numerical model including the viscous effect of the perforated plates through the Darcy’s law. The hybrid finite element-boundary element(FE-BE) method is implemented to determine the response reduction of VLFS with attached perforated plates under various oblique incident ***, the numerical solutions are validated against a series of experimental tests. The effectiveness of the attached perforated plates in reducing the deflections of the VLFS can be significantly improved by selecting the proper design parameters such as the porous parameter, submergence depth, plate width and inclination angle for the given sea conditions.

关键词： very large floating structure(VLFS) anti-motion device hydroelastic response numerical analysis experiment

Stochastic community assembly of abundant taxa maintains the relationship of soil biodiversity-multifunctionality under mercury stress

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Soil Ecology Letters 2024年第2期6卷 163-177页

作者： Shuai Du Xin-Qi Li Li Bi Dong Zhu Hang-Wei Hu Xiuli Hao Jiao Feng Qiaoyun Huang Yu-Rong Liu Key Laboratory of Urban Environment and Health Ningbo Urban Environment Observation and Research StationInstitute of Urban EnvironmentChinese Academy of SciencesXiamen361021China College of Resources and Environment Huazhong Agricultural UniversityWuhan430070China school of Agriculture and Food Faculty of Veterinary and Agricultural SciencesThe University of MelbourneParkvilleVIC3010Australia Hubei Key Laboratory of Soil Environment and Pollution Remediation Huazhong Agricultural UniversityWuhan430070China

Soil abundant taxa diversity positively related to multifunctionality under Hg stress.•Microbial network complexity of soil abundant taxa supported the strength of SBF.•Stochastic assembly of soil abundant subcommunity supported the strength of SBF.•Stochastic ratio was the most important predictor for the strength of *** is known that soil microbial communities are intricately linked to multiple ecosystem functions and can maintain the relationship between soil biodiversity and multifunctionality(SBF)under environmental ***,the relative contributions and driving forces of abundant and rare taxa within the communities in maintaining soil biodiversity-multifunctionality relationship under pollution stresses are still ***,we conducted microcosm experiments to estimate the importance of soil abundant and rare taxa in predicting these relationships under heavy metal mercury(Hg)stress in paired paddy and upland *** results revealed that the diversity of abundant taxa,rather than rare taxa,was positively related to multifunctionality,with the abundant subcommunity tending to maintain a larger proportion of soil functions including chitin degradation,protein degradation,and phosphorus *** multitrophic network complexity consisting of abundant species showed positive correlations with biodiversity and multifunctionality,and supported the strength of SBF within a network complexity *** assembly processes of the abundant subcommunity were positively correlated with the strength of SBF,although stochastic processes decreased the biodiversity and the multifunctionality,*** simultaneously accounting for multiple factors on the strength of SBF,we found that the stochastic community assembly ratio of abundant taxa was the most important predictor for SBF strength under Hg *** results highlight the importance of abundant taxa in supporting soil multifunctionality,and elucidate the linkages between co

关键词： abundant taxa biodiversity-multifunctionality relationship community assembly network complexity environmental stresses

Perturbations in the uterine luminal fluid composition are detrimental to pregnancy establishment in cattle

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Journal of Animal science and Biotechnology 2019年第1期10卷 56-66页

作者： Thiago Martins Guilherme Pugliesi Mariana Sponchiado Angela M.Gonella-Diaza Oscar A.Ojeda-Rojas Frederich D.Rodriguez Roney S.Ramos Andrea C.Basso Mario Binelli Department of Animal Reproduction School of Veterinary Medicine and Animal ScienceUniversity of Sao Paulo Department of Nutrition and Animal Production School of Veterinary Medicine and Animal ScienceUniversity of Sao Paulo University Corporation of Huila ABS Global In Vitro Brasil Department of Animal sciences University of Florida

Background: A major,unresolved issue is how the uterine microenvironment determines pregnancy success in *** implantation,conceptus development depends on the uterine secretome(i.e.,histotroph).Despite its pivotal role,little is known about the dynamics of histotroph synthesis and changes in composition throughout the early diestrus and the relevance to pregnancy *** hypothesize that disturbances on histotroph composition affect the establishment of *** was to disturb histotroph composition at early diestrus and verify the effects on:(Exp.1) timing to restore its composition; and(Exp.2) pregnancy rate after multiple-embryo *** cycle of multiparous Nelore cows were synchronized and estrus was considered d 0(D0) of the *** was through flushing each uterine horn with 30 m L of DMPBS and collecting the resulting uterine luminal flushing(ULF) on D1; D4; D7; D1 + D4 + *** group remained *** Exp.1,ULF was collected on D7.5 from all animals and used for quantification of total protein concentration and abundance of *** Exp.2,three in vitro-produced embryos were transferred to the uterine horn ipsilateral to the ovary containing the CL on D7.5 and pregnancy was checked on D25 by ***: In Exp.1,ULF collection on D4 or D7 increased(1.5-to 2.2-folds) the total protein concentration and albumin *** collection on D1 did not alter(P > 0.10) these *** Exp.2,ULF collected on D4 or D7 decreased pregnancy rates to approximately half of that measured in the remaining ***: Subtle perturbations imposed to the native intrauterine milieu,such as those caused by a single,low-volume collection of ULF,profoundly disturbs intrauterine composition and pregnancy *** least 4 d were necessary for the uterus to recover its composition and the functional capacity to carry post-implantation gestation.

关键词： Albumin Embryo Histotroph Protein

Continuous-Time Prediction of Industrial Paste Thickener System With Differential ODE-Net

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 686-698页

作者： Zhaolin Yuan Xiaorui Li Di Wu Xiaojuan Ban Nai-Qi Wu Hong-Ning Dai Hao Wang the Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Artificial IntelligenceBeijing Key Laboratory of Knowledge Engineering for Materials ScienceSchool of Computer and Communication EngineeringUniversity of Science and Technology Beijing the Department of ICT and Natural science Norwegian University of Science and Technology IEEE the Institute of Systems Engineering and Collaborative Laboratory for Intelligent Science and SystemsMacao University of Science and Technology the Department of Computing and Decision sciences Lingnan University the Department of Computer science Norwegian University of Science and Technology

It is crucial to predict the outputs of a thickening system,including the underflow concentration(UC)and mud pressure,for optimal control of the *** proliferation of industrial sensors and the availability of thickening-system data make this ***,the unique properties of thickening systems,such as the non-linearities,long-time delays,partially observed data,and continuous time evolution pose challenges on building data-driven predictive *** address the above challenges,we establish an integrated,deep-learning,continuous time network structure that consists of a sequential encoder,a state decoder,and a derivative module to learn the deterministic state space model from thickening *** a case study,we examine our methods with a tailing thickener manufactured by the FLSmidth installed with massive sensors and obtain extensive experimental *** results demonstrate that the proposed continuous-time model with the sequential encoder achieves better prediction performances than the existing discrete-time models and reduces the negative effects from long time delays by extracting features from historical system *** proposed method also demonstrates outstanding performances for both short and long term prediction tasks with the two proposed derivative types.

关键词： Industrial 24 paste thickener ordinary differential equation(ODE)-net recurrent neural network time series prediction

Effect of grassland mosaic structure and dynamism on the reproductive habitat suitability for Alectoris graeca in central Apennines

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Journal of Mountain science 2019年第12期16卷 2783-2792页

作者： Andrea BRUSAFERRO Valentina IESARI Federico Maria TARDELLA Paola SCOCCO Andrea CATORCI school of Biosciences and veterinary Medicine University of Camerino

Over the last several decades,the Mediterranean region has been subjected to mountain abandonment and farming cessation,leading to changes in vegetation and coenological features of grasslands,contextually to the strong decline of the rock partridge(Alectoris graeca).Our hypothesis was that the ongoing dynamic processes leading to the compositional changes of grasslands in central Apennines affect the habitat suitability for the singing male(territorial male defending its reproductive site).In 2015,we defined the presence/absence of spring territorial singing males in seven sites(1,250-2,400 m a.s.l.),by the census in 74 playback stations,distributed along 15 *** characterized the topography and the vegetation mosaic of such sites according to the collected topographic and vegetation cover data in 59 randomly selected plots(100 m×100 m)along the *** understand the relations among the environmental variables and the effect of the composition and dynamism of the vegetation mosaics on the presence/absence of the singing male,we used principal components analysis and generalized linear mixed-effect *** results emphasized the marked overlap between the general environmental conditions,which proved to define the habitat suitability for ***,and the characteristics of the site chosen by the singing male for starting the reproductive ***,we found that the site suitability for the singing male decreases when the vegetation recovery processes are ongoing,because of the spread of coarse tall grassesdominated communities and/or grassland types with dense *** grass-dominated communities and thick-turf grasslands exert their negative effect decreasing the habitat suitability for the singing male starting from low cover ***,it is conceivable that singing male’s suitable habitat will be dramatically restricted to the steepest south-facing slopes,where topographic and soil conditions do not allow the spread of grassl

关键词： Brachypodium genuense Grazing cessation Reproductive habitat suitability Rock partridge Singing male Vegetation recovery processes