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Optimal Release Control of Companion Satellite System Using Electromagnetic Forces
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作者 Zengwen Xu Peng Shi Yushan Zhao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第4期27-35,共9页
Electromagnetic forces generated by the inter-action of component satellites can be used to release companion satellites. Optimal release trajectories for companion satellite system using inter-electromagnetic forces ... Electromagnetic forces generated by the inter-action of component satellites can be used to release companion satellites. Optimal release trajectories for companion satellite system using inter-electromagnetic forces were investigated. Firstly,nonlinear relative motion dynamic equations of a two-craft electromagnetic companion satellite system were derived in spatial polar coordinates. Then principles of electromagnetic satellite formation flying were introduced. Secondly,the characteristics of the electromagnetic companion satellites release were analyzed and optimal release trajectories of companion satellites using electromagnetic forces were obtained using Gauss pseudospectral method. Three performance criteria were chosen as minimum time,minimum acceleration of the separation distance and minimum control acceleration. Finally,three release examples including expansion along separation distance, rotation in orbital plane and stable formation reconfiguration were given to demonstrate the feasibility of this method. Results indicated that the release trajectories can converge to optimal solutions effectively and the concept of release companion satellites using electromagnetic forces is practicable. 展开更多
关键词 companion satellites electromagnetic formation flying optimal release trajectory Gauss pseudospectral method
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闽楠-木荷混交林空间结构及其养分利用 被引量:1
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作者 李铁华 李阳宁 +1 位作者 闫旭 张心艺 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第2期1-9,117,共10页
【目的】为探讨混交林中闽楠和木荷的种间关系,确定木荷能否作为闽楠的伴生树种营建健康高效的闽楠-木荷混交林。【方法】以金洞林场16年生的闽楠-木荷混交林以及闽楠纯林、木荷纯林为研究对象,通过分析闽楠-木荷混交林的根系分布特性... 【目的】为探讨混交林中闽楠和木荷的种间关系,确定木荷能否作为闽楠的伴生树种营建健康高效的闽楠-木荷混交林。【方法】以金洞林场16年生的闽楠-木荷混交林以及闽楠纯林、木荷纯林为研究对象,通过分析闽楠-木荷混交林的根系分布特性与林分空间结构特性来探讨闽楠-木荷混交林地上与地下部分的种间关系;通过分析不同物候期下3种林分的闽楠与木荷叶片养分的动态规律来阐明闽楠与木荷之间的养分利用关系。【结果】1)在16年生闽楠-木荷混交林中,在闽楠周围1.5 m内闽楠和木荷的根系分布虽有部分重叠,但闽楠仍占据优势地位,闽楠和木荷在地下生长空间和养分吸收利用方面存在竞争但竞争不激烈;2)整体林分空间结构上,闽楠、木荷纯林略优于闽楠-木荷混交林,说明混交林的树种不同,树种之间的生长特性和生态特性不一样,林分的均一性会差一些,对其调整结构的难度要大于纯林。混交林中,木荷已对闽楠形成了一定的竞争优势;3)闽楠-木荷混交林中,对养分吸收利用在物候期上部分不同步,存在相对有利的互补关系;从所有的物候期来看,闽楠叶片的N、P、K含量在大部分时期都高于木荷,表明闽楠-木荷混交更有利于闽楠对养分的吸收利用,木荷对养分的需求更低;4)16年生混交林中闽楠、木荷的生长速度要优于相应的纯林,表明前期竞争促进了林分的生长。【结论】闽楠与木荷混交有利于闽楠获得更多的养分,适度竞争促进了林木的生长,木荷是闽楠较好的伴生树种。 展开更多
关键词 闽楠-木荷混交林 根系 林分空间结构 养分含量 伴生树种
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城市宠物源细菌耐药性研究进展 被引量:1
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作者 吴雨珊 孙冰清 +3 位作者 姜芹 张妤 顾欣 张文刚 《中国动物传染病学报》 CAS 北大核心 2024年第3期227-236,共10页
随着宠物抗菌药物使用量的逐年增多,宠物源细菌耐药水平不断攀升。本文就国内外宠物源细菌耐药性危害、宠物源大肠埃希菌、肠球菌、沙门菌、金黄色葡萄球菌等的耐药性进行综述,并针对我国宠物源耐药性现状,提出应建立宠物源细菌耐药性... 随着宠物抗菌药物使用量的逐年增多,宠物源细菌耐药水平不断攀升。本文就国内外宠物源细菌耐药性危害、宠物源大肠埃希菌、肠球菌、沙门菌、金黄色葡萄球菌等的耐药性进行综述,并针对我国宠物源耐药性现状,提出应建立宠物源细菌耐药性监测体系,分析宠物源细菌耐药性变化及趋势,加强宠物用抗菌药物的使用管理与统计,加强科学养宠与科学用药的宣传教育等应对措施,为遏制动物源细菌耐药性问题提供参考。 展开更多
关键词 伴侣动物 细菌 抗菌药物 耐药性 监测体系
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Discovery and Application of the Companion Fungus Related to Sclerotial Formation from Hyphae of Grifola umbellata 被引量:3
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作者 郭顺星 王秋颖 +2 位作者 庄文颖 张集慧 邢晓科 《Acta Botanica Sinica》 CSCD 2002年第10期1151-1154,共4页
The companion fungus ( Grifola sp.) related to sclerotial formation from hyphae of Grifola umbellata (Pers.) Pilat was isolated from the cavity associated with sclerotia of G. umbellata in natural condition. Experimen... The companion fungus ( Grifola sp.) related to sclerotial formation from hyphae of Grifola umbellata (Pers.) Pilat was isolated from the cavity associated with sclerotia of G. umbellata in natural condition. Experimental results showed that the pure culture of G. umbellata was unable to form sclerotia, whereas sclerotia produced easily in flasks or on trunks when the companion fungus was inoculated together with strain of G. umbellata. The companion fungus is critical for sclerotium formation from hyphae of G. umbellata. Morphological differences were found in cultures of the two fungi. The companion fungus possesses thin-walled narrow hyphae, while G. umbellata is of wider hyphae which are either thick- or thin-walled. 展开更多
关键词 Grifola umbellata companion fungus SCLEROTIA
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MATRICES OVER A REDUCED RING AS SUMS OF THREE TRIPOTENTS
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作者 HUANG Tao CUI Jian ZENG Yue-di 《数学杂志》 2024年第5期406-412,共7页
In this paper,we study reduced rings in which every element is a sum of three tripotents that commute,and determine the integral domains over which every n£n matrix is a sum of three tripotents.It is proved that ... In this paper,we study reduced rings in which every element is a sum of three tripotents that commute,and determine the integral domains over which every n£n matrix is a sum of three tripotents.It is proved that for an integral domain R,every matrix in M_(n)(R)is a sum of three tripotents if and only if R■Zp with p=2,3,5 or 7. 展开更多
关键词 Tripotent companion matrix reduced ring matrix ring
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Dehydrated Natural Feed for Cats: Influence on Apparent Digestibility Coefficient, Feces Scores, and Serum Immune, Antioxidant, and Metabolic Biomarkers
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作者 Bruno Giorgio de Oliveira Cécere Guilherme Luiz Deolindo +8 位作者 Bianca F. Bissacotti Priscila Marquezin Copetti Maria Rosa Chitolina Schetinger Bruna Klein Matheus Delamea Baldissera Thiago Pereira Ribeiro Walter Hugo Cuelho Suarez Daniel Pigatto Monteiro Aleksandro Schafer Da Silva 《Food and Nutrition Sciences》 CAS 2024年第7期594-611,共18页
The present study aimed to determine whether natural dehydrated feed (DNF) can replace dry extruded feed while preserving the required daily intake, nutrient digestibility and benefits for immunity and antioxidant res... The present study aimed to determine whether natural dehydrated feed (DNF) can replace dry extruded feed while preserving the required daily intake, nutrient digestibility and benefits for immunity and antioxidant response in cats. The animals were divided into two groups of seven animals each. One group received DNF, and the other consumed commercial extruded dry feed (DCF). The experiment lasted 45 days and we measured daily consumption and collected blood and feces samples. The animals in the DNF group showed greater digestibility of fiber and mineral matter than DCF. Cats in the DNF group had a higher volume of feces. DNF cats had lower leukocyte and granulocyte counts and cholesterol levels. Serum enzymatic antioxidant responses and non-enzymatic were higher in DNF cats. Cats in the DNF group showed lower serum acute phase proteins in addition to a tendency toward a higher concentration of transferrin than in the DCF group. Fecal Escherichia coli and total coliform counts of cats fed DNF were higher than DCF. We conclude that the daily consumption of cats is adequate. This feed had greater digestibility of fiber and mineral matter, in addition to an improvement in antioxidant and immunological responses. 展开更多
关键词 Alternative Feed ANTIOXIDANT companion Animals Health
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基于“伴读者体系”的小学语文课堂教学设计研究
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作者 王施 《教育教学研究前沿》 2024年第7期58-60,共3页
伴读者体系旨在通过构建一个由教师引导、学生主体、家长及社区成员等多方参与的共读环境,形成以阅读为核心,融合听说读写多项技能培养的综合学习生态系统。基于伴读者体系的小学语文课堂教学设计是一种新的教学尝试,它可以为学生提供... 伴读者体系旨在通过构建一个由教师引导、学生主体、家长及社区成员等多方参与的共读环境,形成以阅读为核心,融合听说读写多项技能培养的综合学习生态系统。基于伴读者体系的小学语文课堂教学设计是一种新的教学尝试,它可以为学生提供更加丰富的学习资源和互动体验,激发学生的学习兴趣和积极性,提高语文教学质量。文章对小学语文教学现状展开了全面分析,并探讨了伴读的意义和形式,最终基于伴读者体系教育视角,提出了几点具体的教学策略,以期为推动学生全面发展提供参考和借鉴。 展开更多
关键词 “伴读者体系” 小学语文 教学策略 现实意义
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Companion diagnostics for the targeted therapy of gastric cancer 被引量:5
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作者 Changhoon Yoo Young Soo Park 《World Journal of Gastroenterology》 SCIE CAS 2015年第39期10948-10955,共8页
Gastric cancer is the fourth most common type ofcancer and represents a major cause of cancer-related deaths worldwide. With recent biomedical advances in our understanding of the molecular characteristics of gastric ... Gastric cancer is the fourth most common type ofcancer and represents a major cause of cancer-related deaths worldwide. With recent biomedical advances in our understanding of the molecular characteristics of gastric cancer, many genetic alterations have been identified as potential targets for its treatment. Multiple novel agents are currently under development as the demand for active agents that improve the survival of gastric cancer patients constantly increases. Based on lessons from previous trials of targeted agents, it is now widely accepted that the establishment of an optimal diagnostic test to select molecularly defined patients is of equal importance to the development of active agents against targetable genetic alterations. Herein, we highlight the current status and future perspectives of companion diagnostics in the treatment of gastric cancer. 展开更多
关键词 companion DIAGNOSTICS GASTRIC CANCER HUMAN epiderm
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Effects of seven different companion plants on cucumber productivity, soil chemical characteristics and Pseudomonas community 被引量:5
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作者 CHANG Chun-ling FU Xue-peng +2 位作者 ZHOU Xin-gang GUO Mei-yu WU Feng-zhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2206-2214,共9页
Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study,... Companion cropping can influence cucumber productivity by altering soil chemical characteristics and microbial communities. However, how these alterations affect the growth of cucumber is still unknown. In this study, seven different plant species were selected as companion plants for testing their effects on cucumber productivity. The effects of different companion plants on changes in soil chemical properties such as electrical conductivity (EC) and contents of essential nutrients as well as the structure and abundance of the soil Pseudomonas community were evaluated. The results showed a higher cucumber yield in the wheat/cucumber companion system than that in the cucumber monocultured and other companion cropping systems. The lowest phosphorus (P) and potassium (K) contents in the soil were found in the cucumber monocultured system, and the highest NO3+-N and NH4*-N contents were observed in the rye/cucumber companion system. PCR-denaturing gradient gel electrophoresis (DGGE) and real-time PCR analysis showed that the trifolium/cucumber companion system increased the diversity of the soil Pseudomonas community, while the chrysanthemum/cucumber companion system increased its abundance. Interestingly, plant-soil feedback trials revealed that inoculating the soil of the wheat/cucumber companion system increased the growth of cucumber seedlings. In conclusion, the effects of different companion plants on cucumber productivity, soil chemical characteristics and the soil Pseudomonas community were different, and wheat was a more suitable companion plant for increasing cucumber productivity. In addition, the altered microbial community caused by companion cropping with wheat contributed to increased cucumber productivity. 展开更多
关键词 CUCUMBER companion plants soil chemical characteristics Pseudomonas community
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Companion矩阵的伪谱问题
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作者 张敏 王正盛 徐贵力 《江苏师范大学学报(自然科学版)》 CAS 2017年第2期49-52,共4页
基于Givens-QR分解,给出了companion矩阵的一种伪谱定义和相应的快速计算方法;利用给出的companion矩阵伪谱作为工具分析了balance技术的作用,说明了balance技术在矩阵计算中的重要性和有效性;针对多项式零点扰动,探讨了companion矩阵... 基于Givens-QR分解,给出了companion矩阵的一种伪谱定义和相应的快速计算方法;利用给出的companion矩阵伪谱作为工具分析了balance技术的作用,说明了balance技术在矩阵计算中的重要性和有效性;针对多项式零点扰动,探讨了companion矩阵的结构伪谱;最后,对文中所给算法进行了数值试验与比较,说明了其正确性和有效性. 展开更多
关键词 伪谱 companion矩阵 BALANCE Givens-QR分解 结构伪谱
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A note on the Moore-Penrose inverse of a companion matrix
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作者 王龙 陈建龙 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期123-126,共4页
Let R be an associative ring with unity 1. The existence of the Moore-Penrose inverses of block matrices overR is investigated and the sufficient ad necessary conditions for such existence are obtained. Furthermore, ... Let R be an associative ring with unity 1. The existence of the Moore-Penrose inverses of block matrices overR is investigated and the sufficient ad necessary conditions for such existence are obtained. Furthermore, the representation of the Moore-Penrose inverse of M=[0 A C B]is given under the condition of EBF - 0, where E - I - CCT and F - I -AfA. This result generalizes the representation of the Moore-Penrose inverse of the companion matrix M =[0 a In b]due to Pedro Patricio. As for applications, some examples are given to illustrate the obtained results. 展开更多
关键词 companion matrix Moore-Penrose inverse RING
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RESEARCH ON THE COMPANION SOLUTION FOR A THIN PLATE IN THE MESHLESS LOCAL BOUNDARY INTEGRAL EQUATION METHOD 被引量:1
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作者 龙述尧 熊渊博 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第4期418-423,共6页
The meshless local boundary integral equation method is a currently developed numerical method, which combines the advantageous features of Galerkin finite element method(GFEM), boundary element method(BEM) and elemen... The meshless local boundary integral equation method is a currently developed numerical method, which combines the advantageous features of Galerkin finite element method(GFEM), boundary element method(BEM) and element free Galerkin method(EFGM), and is a truly meshless method possessing wide prospects in engineering applications. The companion solution and all the other formulas required in the meshless local boundary integral equation for a thin plate were presented, in order to make this method apply to solve the thin plate problem. 展开更多
关键词 thin plate companion solution meshless local boundary integral equation method
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Experiences of women with the support they received from their birth companions during labour and delivery in Malawi 被引量:1
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作者 Esther Kungwimba Address Malata +1 位作者 Alfred Maluwa Ellen Chirwa 《Health》 2013年第1期45-52,共8页
A study was conducted to describe the experiences of primiparous women with the support they received from their birth companions during labour and delivery in Malawi. The study design was descriptive and utilized qua... A study was conducted to describe the experiences of primiparous women with the support they received from their birth companions during labour and delivery in Malawi. The study design was descriptive and utilized qualitative data collection and analysis method on a sample of 20 primiparous women. The women were recruited from the postnatal ward of Bwaila hospital and were interviewed regarding their experiences on the support they received from their birth companions during labour and delivery using an open ended interview guide. Data was manually analyzed using content analysis. Primiparous women described the support they received from their birth companions as useful and beneficial. Birth companions provided advice, physical, emotional and spiritual support to the women during their labour and delivery. In addition, the birth companions were viewed as guardians of the women during labour and delivery. Results however, show that some women were not properly assisted by their companions because both the mothers and companions lacked knowledge on birth companionship. The results further show that birth companions play important roles during the birth and delivery of primiparous women and thereby improving birth outcomes. Therefore, there is a need to train the companions regarding support to a woman during labour and delivery. Primiparous women also need to be trained during antenatal care education so that they properly understand the roles of a birth companion as opposed to those of the midwives. 展开更多
关键词 PRIMIPAROUS Woman BIRTH companion Labour Delivery SUPPORT ANTENATAL Clinic Education BIRTH Experience
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Bounds for Polynomial’s Roots from Fiedler and Sparse Companion Matrices for Submultiplicative Matrix Norms 被引量:1
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作者 Mamoudou Amadou Bondabou Ousmane Moussa Tessa Amidou Morou 《Advances in Linear Algebra & Matrix Theory》 2021年第1期1-13,共13页
We use submultiplicative companion matrix norms to provide new bounds for roots for a given polynomial <i>P</i>(<i>X</i>) over the field C[<i>X</i>]. From a <i>n</i>... We use submultiplicative companion matrix norms to provide new bounds for roots for a given polynomial <i>P</i>(<i>X</i>) over the field C[<i>X</i>]. From a <i>n</i>×<i>n</i> Fiedler companion matrix <i>C</i>, sparse companion matrices and triangular Hessenberg matrices are introduced. Then, we identify a special triangular Hessenberg matrix <i>L<sub>r</sub></i>, supposed to provide a good estimation of the roots. By application of Gershgorin’s theorems to this special matrix in case of submultiplicative matrix norms, some estimations of bounds for roots are made. The obtained bounds have been compared to known ones from the literature precisely Cauchy’s bounds, Montel’s bounds and Carmichel-Mason’s bounds. According to the starting formel of <i>L<sub>r</sub></i>, we see that the more we have coefficients closed to zero with a norm less than 1, the more the Sparse method is useful. 展开更多
关键词 Fiedler Matrices Polynomial’s Roots Bounds for Polynomials companion Matrices Sparse companion Matrices Hessenberg Matrices Submultiplicative Matrix Norm
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SciMed Ltd Companion Ⅲ颈颅多普勒综合故障检修一例
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作者 石坚 罗峥 《医疗装备》 2016年第12期54-55,共2页
SciM ed Ltd Companion III二通道八深度颈颅多普勒检测仪(前身为EME公司产品)内部结构主要有三大部分组成。电源部分:主机电源部分,采用单相AC 220V输入,提供DC12V和DC5V直流电源输出;二次供电部分,主要为数据采集板提供电源。电脑... SciM ed Ltd Companion III二通道八深度颈颅多普勒检测仪(前身为EME公司产品)内部结构主要有三大部分组成。电源部分:主机电源部分,采用单相AC 220V输入,提供DC12V和DC5V直流电源输出;二次供电部分,主要为数据采集板提供电源。电脑部分:主要采用INTEL公司的迅驰移动式Inter Pen IV CPU,低功耗工业计算机专用主板, 展开更多
关键词 companion Ⅲ颈颅多普勒 综合故障 检修
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Closed-form Solutions to the Matrix Equation AX-EXF=BY with F in Companion Form
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作者 Bin Zhou Guang-Ren Duan 《International Journal of Automation and computing》 EI 2009年第2期204-209,共6页
A closed-form solution to the linear matrix equation AX-EXF = BY with X and Y unknown and matrix F being in a companion form is proposed, and two equivalent forms of this solution are also presented. The results provi... A closed-form solution to the linear matrix equation AX-EXF = BY with X and Y unknown and matrix F being in a companion form is proposed, and two equivalent forms of this solution are also presented. The results provide great convenience to the computation and analysis of the solutions to this class of equations, and can perform important functions in many analysis and design problems in descriptor system theory. The results proposed here are parallel to and more general than our early work about the linear matrix equation AX-XF = BY . 展开更多
关键词 Linear matrix equations closed-form solutions right factorizations descriptor linear systems companion matrix.
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Recent clinical trials of cancer immunogene therapy in companion animals
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作者 Liliana ME Finocchiaro Gerardo C Glikin 《World Journal of Experimental Medicine》 2017年第2期42-48,共7页
This mini-review presents the results of veterinary clinical trials on immunogene therapy published from 2014 to 2016. A variety of tumors, among them melanoma(canine and equine), mastocytoma(canine), mammary adenocar... This mini-review presents the results of veterinary clinical trials on immunogene therapy published from 2014 to 2016. A variety of tumors, among them melanoma(canine and equine), mastocytoma(canine), mammary adenocarcinoma(canine) and fibrosarcoma(feline) were treated by using diverse strategies. Non-viral vectors were usually employed to transfer genes of cytokines, suicide enzymes and/or tumor associated antigens. In general terms, minor or no adverse collateral effects were related to these procedures, and treated patients frequently improved their conditions(better quality of life, delayed or suppressed recurrence or metastatic spread, increased survival). Some of these new methodologies have a promising future if applied as adjuvant treatments of standard approaches. The auspicious results, derived from immunogene therapy studies carried out in companion animals, warrant their imperative usage in veterinary clinical oncology. Besides, they provide a strong preclinical basis(safety assays and proofs of concept) for analogous human clinical trials. 展开更多
关键词 CANCER Gene therapy IMMUNOTHERAPY companion ANIMALS Comparative ONCOLOGY
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Families and Companion Animals in a Contemporary World: A Study of Bodies, Minds, and Emotions in Brazilian Cyberspace
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作者 Lavinia Davis Rangel Pessanha Roberto Luiz da Silva Carvalho 《Sociology Study》 2014年第6期544-553,共10页
The objective of this paper is to present the result of a research of images and messages addressed to pet owners, posted in news and advertising websites in Brazilian cyberspace in the period between 2005 and 2012. T... The objective of this paper is to present the result of a research of images and messages addressed to pet owners, posted in news and advertising websites in Brazilian cyberspace in the period between 2005 and 2012. There are a wide variety of pet products and services, similar to those available to the human being and note that pet care industry address the posts to pet owners and the messages intend to motivate the emotions and feelings for the animals, in a sentimental anthropomorphism process. The marketing messages are similar to those of products shaped to induce a person to buy luxury products. Market social interaction is driven by both the human-animal bond and the pet care market campaigns advertisement. In many situations, people interact with pet as a person or a member of the family, as a unique and special living being. The authors conclude that in families which people and animal interacts, new meanings emerge from this contact. 展开更多
关键词 Family and companion animal relations consumption AFFECTIVITY
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一机多能——Cruzer Micro MP3 Companion
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《数码》 2004年第2期30-30,共1页
关键词 SanDisk公司 MP3播放器 CRUZER MICRO MP3 companion 功能
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Pets Are Our Best Companions
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《China Today》 2000年第5期58-60,共3页
Paula Hagen-Peterson an American reader, asked us in a recent letter, ’’Pats are treated as family members in many countries. Can you tell me how dogs, cats, birds and horses are treated in China" Many readers ... Paula Hagen-Peterson an American reader, asked us in a recent letter, ’’Pats are treated as family members in many countries. Can you tell me how dogs, cats, birds and horses are treated in China" Many readers have asked us this very question and so to satisfy their curiosity, China Today has asked several Chinese pet owners to talk about their relationships with their pets. Nowadays, Chinese not only like to raise traditional pets such as cats and dogs, but they also enjoy raising lizards end snaker. 展开更多
关键词 Pets Are Our Best companions
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