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农业工程学报 2018年第7期34卷 52-58页

作者：张智泓张广凯佟金赖庆辉高旭航唐莹 Stephen carr 昆明理工大学现代农业工程学院昆明650500 美国农业部农业应用技术研究中心伍斯特44691 吉林大学工程仿生教育部重点实验室长春130025 昆明医科大学电子显微镜实验室昆明650500 国际田间水土资源循环利用设施公司美国塞勒姆印第安纳州47167

为探索克氏原鳌虾(Procambarus clarkii)在泥浆中穿行的防黏耐磨机理,该文以克氏原鳌虾头胸部外骨骼作为研究对象,分析其无机元素含量和存在形态,观察其微观结构,并测量其硬度和弹性模量;对外骨骼进行摩擦磨损试验,考察其摩擦磨损特性,... 详细信息

为探索克氏原鳌虾(Procambarus clarkii)在泥浆中穿行的防黏耐磨机理,该文以克氏原鳌虾头胸部外骨骼作为研究对象,分析其无机元素含量和存在形态,观察其微观结构,并测量其硬度和弹性模量;对外骨骼进行摩擦磨损试验,考察其摩擦磨损特性,并观察磨痕的磨损形貌。试验表明,克氏原螯虾头胸部外骨骼中含有大量的钙元素,其中大部分以非晶结构存在,并含有少量碳酸钙;外骨骼表面具有凹坑、凸包和刚毛微观结构;螺旋夹板层具有蜂房结构,钙盐以针簇状分布在螺旋夹板层中;外骨骼硬度为0.503 GPa、弹性模量为18.019 GPa;摩擦因数呈跳跃式变化,最小时不足0.1,最大时接近0.8,磨损类型属于磨粒磨损。研究结果为农业机械触土部件表面防黏、耐磨的仿生设计提供理论依据。

关键词：微观结构摩擦硬度外骨骼微观结构弹性模量摩擦磨损

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用临界前反射和折射资料反演地震资料

世界地震译丛 1989年第1期20卷 43-49页

作者： carr.,PM 李平

Gas-propelled nanomotors alleviate colitis through the regulation of intestinal immunoenvironment-hematopexis-microbiota circuits

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2732-2747页

作者： Bo Xiao Yuqi Liang Ga Liu Lingshuang Wang Zhan Zhang Libin Qiu Haiting Xu Sean carr Xiaoxiao Shi Rui LReis Subhas CKundu Zhenghua Zhu Department of Gastroenterology the First Affiliated Hospital of Nanchang UniversityNanchang 330006China College of Sericulture Textileand Biomass SciencesSouthwest UniversityChongqing 400715China Department of Neurology School of MedicineEmory UniversityAtlantaGA 30322USA Atlanta Veterans Affairs Medical Center DecaturGA 30033USA Department of Surgery School of MedicineEmory UniversityAtlantaGA 30322USA Bs Research Group I3Bs—Research Institute on BiomaterialsBiodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAveParkBarcoGuimaraes 4805-017Portugal

The progression of ulcerative colitis(UC)is associated with immunologic derangement,intestinal hemorrhage,and microbiota *** traditional medications mainly focus on mitigating inflammation,it remains challenging to address multiple ***,a versatile gas-propelled nanomotor was constructed by mild fusion of post-ultrasonic CaO_(2) nanospheres with Cu_(2)O *** resulting CaO_(2)–Cu_(2)O possessed a desirable diameter(291.3 nm)and a uniform size *** could be efficiently internalized by colonic epithelial cells and macrophages,scavenge intracellular reactive oxygen/nitrogen species,and alleviate immune reactions by pro-polarizing macrophages to the anti-inflammatory M2 *** nanomotor was found to penetrate through the mucus barrier and accumulate in the colitis mucosa due to the driving force of the generated oxygen *** administration of CaO_(2)–Cu_(2)O could stanch the bleeding,repair the disrupted colonic epithelial layer,and reduce the inflammatory responses through its interaction with the genes relevant to blood coagulation,anti-oxidation,wound healing,and ***,it restored intestinal microbiota balance by elevating the proportions of beneficial bacteria(e.g.,Odoribacter and Bifidobacterium)and decreasing the abundances of harmful bacteria(e.g.,Prevotellaceae and Helicobacter).Our gas-driven CaO_(2)–Cu_(2)O offers a promising therapeutic platform for robust treatment of UC via the rectal route.

关键词： Nanomotor Anti-inflammation Blood coagulation Immune regulation Hematopexis Microbiota rebalance Ulcerative colitis Rectal administration

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农业机器的模糊逻辑控制导航

农业机械学报 2000年第3期31卷 31-34页

作者：应火冬 HagrasH Callaghan V Colley M carr-West A 中国水稻研究所农业工程室杭州市310006 ComputerScienceDepartment EssexUniversity ComputerScienceDepartment iculturalEngineeringDepartment WrittleAgriculturalCollege

介绍了一台试验车控制系统的构造 ,设计了一个以实现收获机械自动引导行走为目标的模糊逻辑控制器。试验表明 ,这一控制器具有抗来自断续、不匀称引导基准的噪声干扰的能力。

关键词：模糊逻辑控制自动引导行走农业机械

Surveys on magnetospheric plasmas based on the Double Star Project (DSP) exploration

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Science China(Technological Sciences) 2008年第10期51卷 1639-1647页

作者： C. P. ESCOUBET C. M. carr H. RME A. FAZAKERLEY H. LAAKSO I. DANDOURAS M. DUNLOP ESA/ESTEC SCI-SH Keplerlaan 1 2200 AG Noordwijk The Netherlands Imperial College of Science Technology and Medicine London SW7 2BZ United Kingdom CESR BP4346 31028 Toulouse Cedex 4 France Mullard Space Science Laboratory Univ. College London Dorking Surrey RH5 6NT United Kingdom Imperial College of Science Technology and Medicine London SW7 2BZ United Kingdom Rutherford Appleton Laboratory Didcot Oxon OX11 0QX United Kingdom

The equatorial and polar satellites of the Double Star Project (DSP) were launched successfully on December 29, 2003 and July 25, 2004, respectively, and both of them are operating smoothly. The DSP provides a good opportunity for investigat-ing the structure of the magnetosphere. Based on the DSP data collected during 2004, we have surveyed the distribution of the magnetic fields and plasmas in the magnetosphere. It is found that: (1) Near the Earth’s equatorial plane within geo-centric distances of less than 7 RE, the Earth’s magnetic field is dipolar. In the vi-cinity of the magnetopause, the magnetic field is enhanced by a factor of about 1.5, and on the nightside, the magnetic field can vary significantly from the Earth’s di-pole field, likely caused by the presence of the near-Earth tail current sheet. (2) In the day-side magnetosheath, the electron and ion densities are usually both in the range of 10―30 cm?3; the ion and electron temperatures are usually about 200 and 50 eV, respectively. The flow pattern is usually smooth, with a low velocity in the subsolar region and with significantly higher velocities in the dawn and dusk flanks. (3) In the region between the magnetopause and plasmasphere the density is low, approximately 0.5―5 cm?3, and the temperature is high, about 1―10 keV for ions and 0.1―5 keV for electrons. The ion temperature has an apparent anisotropy, with the ratio of the perpendicular and parallel temperatures being about 1.0―1.3 for the night- and dusk-side magnetosphere and about 1.3―2.0 for the day- and dawn-side magnetosphere. There is an evident sunward convection of about 50 km/s in the magnetosphere. On the dawn side, the flow becomes somewhat turbulent, and in the vicinity of the night-noon meridian plane, the convection is rather slow. (4) The high-energy electrons with energies higher than 2 MeV are mainly located in the regions with 3 < L < 4.5; the size of the high-energy electrons area varies with time, it may expand and shrink

关键词： Earth’s magnetosphere space exploration geomagnetic field space plasmas

Depth to the apparent redox potential discontinuity(aRPD)as a parameter of interest in marine benthic habitat quality models

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International Journal of Sediment Research 2018年第2期33卷 149-156页

作者： Travis G.Gerwing Kieran Cox Alyssa M.Allen Gerwing Charmaine N.carr-Harris Sarah E.Dudas Francis Juanes Ecosystem Science and Management Program University of Northern British Columbia Department of Biology University of Victoria Skeena Fisheries Commission 4. Department of Biology Vancouver Island University

The usefulness of the apparent redox potential discontinuity(aRPD) in assessments of marine benthic habitat quality was explored at two intertidal mudflats along the north Pacific coast of Canada. Two transects were established at each intertidal site, with three sediment biogeochemistry cores collected from each transect four times over the summer of 2016. Measurements of the sediment pore water dissolved oxygen(DO) content and redox(Eh) conditions were taken at the surface of the core(measured vertically), as well as at increasing depths(1 cm between readings) into the sediment(measured horizontally through predrilled holes in the biogeochemistry corer). While oxic, anoxic, oxidized, and reduced sediment pore water was observed above and below the aRPD, in general, sediment above the aRPD had higher DO content, and higher Eh values than sediment below the aRPD. Therefore, the aRPD depth can be used as a relative indicator of sediment pore water DO and Eh conditions: sediment with a deeper aRPD depth has more available DO, and the pore water has higher Eh values(more oxidized or less reduced) than sediment with a shallower aRPD depth. As such, the aRPD depth is a useful parameter to include in models that assess the quality of marine benthic habitats.

关键词： Anoxia Apparent redox potential discontinuity(aRPD) Dissolved oxygen Habitat quality Hypoxia Intertidal Marine benthos Sediment pore water

Genitourinary melanoma:An overview for the clinician

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Asian Journal of Urology 2022年第4期9卷 407-422页

作者： Danielle K.DePalo Kelly M.Elleson Michael J.carr Philippe E.Spiess Jonathan S.Zager Department of Cutaneous Oncology Moffitt Cancer CenterTampaFLUSA Department of Surgery University of LouisvilleLouisvilleKYUSA Department of Genitourinary Oncology Moffitt Cancer CenterTampaFLUSA

Genitourinary (GU) melanoma is a rare presentation of melanoma accounting for approximately 0.5% of all *** melanomas include primary melanomas of the vulva,vagina,uterine cervix,ovary,penis,scrotum,urethra,bladder,ureter,and *** melanomas are often diagnosed in advanced stages and stigma is thought to contribute to delays in *** the likely diagnosing provider,it is imperative that dermatologists,urologists,and gynecologists are aware of these uncommon sites of *** there have been major advances in the treatment of melanomas as a whole in the last 10 years,their applications to GU melanomas have often been *** melanomas have not been included in many of the major phase II clinical trials which brought contemporary advanced treatments to market and the prognoses for GU melanomas remain *** to the rarity of GU melanomas,much of the literature provides gener alized recommendations across multiple different organs affected by GU melanomas or omits certain topics,making it difficult to appreciate the funda-mentals of the individual *** review aimed to provide background information on the pathogenesis and epidemiology of the different sites of GU melanomas and categorize data specific to the presentation,staging,treatment,and prognosis of each type of GU melanoma to guide the *** was also meant to encourage a multidisciplinary approach to the management of these patients as it spans the expertise of surgical oncologists,medical oncologists,radiation oncologist,dermatologists,urologists,and gynecologists.

关键词： Genitalia Female Male Melanoma Rare diseases Staging Treatment Urinary tract

Physical and chemical changes of rapeseed meal proteins during toasting and their effects on in vitro digestibility

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Journal of Animal Science and Biotechnology 2017年第2期8卷 417-427页

作者： Sergio Salazar-Villanea Erik M.A.M.Bruininx Harry Gruppen Wouter H.Hendriks Patrick carré Alain Quinsac Antonius F.B.van der Poel Wageningen Livestock Research P.O.Box 3386700 AH WageningenThe Netherlands Animal Nutrition Group Wageningen University&ResearchP.O.Box 3386700 AH WageningenThe Netherlands Agfifirm Innovation Center Royal Dutch Agrifirm GroupP.O.Box 200187302 HA ApeldoornThe Netherlands Laboratory of Food Chemistry Wageningen University&ResearchP.O.Box 176700 AA WageningenThe Netherlands CREOL/OLEAD 11 rue MongeParc Industriel33600 PessacFrance Terres Inovia 11 rue MongeParc Industriel33600 PessacFrance

Background： Toasting during the production of rapeseed meal（RSM） decreases ileal crude protein（CP） and amino acid（AA） digestibility. The mechanisms that determine the decrease in digestibility have not been fully elucidated. A high protein quality, low-denatured, RSM was produced and toasted up to 120 min, with samples taken every 20 min. The aim of this study was to characterize secondary structure and chemical changes of proteins and glucosinolates occurring during toasting of RSM and the effects on its in vitro CP ***： The decrease in protein solubility and the increase of intermolecular β-sheets with increasing toasting time were indications of protein aggregation. The contents of NDF and ADIN increased with increasing toasting *** of arginine, lysine and O-methylisourea reactive lysine（OMIU-RL） linearly decreased with increasing toasting time, with a larger decrease of OMIU-RL than lysine. First-order reactions calculated from the measured parameters show that glucosinolates were degraded faster than lysine, OMIU-RL and arginine and that physical changes to proteins seem to occur before chemical changes during toasting. Despite the drastic physical and chemical changes noticed on the proteins, the coefficient of in vitro CP digestibility ranged from 0.776 to 0.750 and there were no effects on the extent of protein hydrolysis after 120 min. In contrast, the rate of protein hydrolysis linearly decreased with increasing toasting time, which was largely correlated to the decrease in protein solubility, lysine and OMIU-RL observed. Rate of protein hydrolysis was more than 2-fold higher for the untoasted RSM compared to the 120 min toasted ***： Increasing the toasting time for the production of RSM causes physical and chemical changes to the proteins that decrease the rate of protein hydrolysis. The observed decrease in the rate of protein hydrolysis could impact protein digestion and utilization.

关键词： Hydrolysis rate In vitro protein digestibility Rapeseed meal Reactive lysine Secondary structure

Differential Relationships among Facets of Alexithymia and BDNF- and Dopamine-Related Polymorphisms

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Neuroscience & Medicine 2012年第1期3卷 7-13页

作者： Nancy S. Koven Leah H. carr Program in Neuroscience Bates College Lewiston Maine USA

Alexithymia refers to a cluster of emotion-related deficits such as difficulty attending to and identifying one’s feelings. Although not a diagnosable psychiatric condition, alexithymia is considered a personality risk factor for multiple pathologies, including somatoform, substance use, eating, and mood disorders. Evidence suggests heritability, but few studies have examined the influence of specific genes on alexithymic traits. Candidate genes explored thus far include those involved in modulation of brain-derived neurotrophic factor (BDNF) and dopamine, two neurotransmitters whose functions have been implicated in human emotion processing. This study investigated the relationship between the C270T polymorphism of the BDNF gene, facets of alexithymia, and possible interactions with the COMT, DAT1, and ANKK1 genes in a sample of 130 healthy adults. Given the multidimensionality of the alexithymia construct and its overlap with the related constructs of emotional intelligence and mood awareness, we used principal components analysis to derive Clarity of Emotion and Attention to Emotion as specific facets of alexithymia. Results showed that the C270T C/C genotype group had lower Clarity of Emotion scores relative to the C/T genotype group, even after covarying for COMT, DAT1, and ANKK1 genotypes. Dopamine-related genes had no association with alexithymia dimensions, nor did they interact with the C270T polymorphism to predict Clarity of Emotion. Although the molecular mechanisms by which this polymorphism influences BDNF are unknown, this study suggests a role for BDNF in modulating aspects of alexithymia. We discuss these results in the context of BDNF’s trophic effects in the nervous system.

关键词： Brain-Derived Neurotrophic Factor Alexithymia Dopamine Polymorphism