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81.
Eduardo Kohn 《Anthrozo?s》2013,26(2):203-206
ABSTRACTAlthough the occurrence of cat-caretaking of free-roaming cats is widespread, particularly so in countries with a climate suitable for cats to reproduce year-round, our knowledge of this relationship is still incomplete. People who engage in daily activities of feeding and caring for groups of free-roaming cats (cat caretakers) are known to be devoted to their cats and invest considerable resources in their care, including neutering and veterinary care. These caretakers often encounter difficulties, such as resentment by neighbors and lack of cooperation or financing by the municipal veterinary services. Despite the fundamental understanding of these caretakers' high daily commitment, and sometimes strong bond with the cats, detailed knowledge is still lacking regarding the nature of this bond, the difficulties that ensue from this daily occupation, and the relationship between the two. The purpose of this study was thus to acquire a deeper understanding, by means of an in-depth interview with cat caretakers. The study has identified, for the first time, two distinct emotional approaches that accompany extensive caretaking for free-roaming cats: emotional attachment and emotional detachment. We show how these two different responses affect both social and financial aspects in the caretakers' lives, and report on the ways in which these individuals experience cat caretaking. Our findings provide a first systematic understanding of the relationship between the level of technical caretaking (feeding, medical care, etc.) and the level of emotional involvement, and reveal the ambivalence often inherent in human–animal relations in general and the caretaker–cat bond in particular. The understanding acquired here can be put into practice to reduce the emotional and technical difficulties experienced by cat caretakers, as well as to improve free-roaming cat management efforts and cat welfare. By increasing public and municipal awareness of the possible contribution of cat caretakers to cat management, and of the emotional and technical difficulties they experience, both the caretakers and other community members can benefit. 相似文献
82.
Spectroscopic techniques were used to investigate the interaction between vanadate and human erythrocyte ghosts. Direct evidence from 51V nuclear magnetic resonance (NMR) studies suggested that the monomeric and polymeric vanadate species may bind to the anion binding sites of band 3 protein of the erythrocyte membrane. The results of 51V NMR studies and the quenching effect of vanadate on the intrinsic fluorescence of the membrane proteins indicated that in the low concentration range of vanadate (<0.6 mm), monomeric vanadate binds mostly to the anion sites of band 3 protein with the dissociation constant close to 0.23 mm. The experiments of sulfhydryl content titration by the method of Ellman and residue sulfhydryl-labeled fluorescence spectroscopies clearly displayed that vanadate reacts directly with sulfhydryl groups. The appearance of the anisotropic election spin resonance (ESR) signal of vanadyl suggests that a small (c. 3%) amount of vanadate was reduced by sulfhydryl groups of membrane proteins. The fluidity and order of intact ghost membrane were reduced by the reaction with vanadate, as shown by the ESR studies employing the protein- and lipid-specific spin labels. It was concluded that although vanadates mainly bind to band 3 protein, a minor part of vanadate may oxidize the residue sulfhydryl groups of membrane proteins, and thus decrease the fluidity of erythrocyte membrane. 相似文献
83.
南昌市不同植物类群叶片氮磷浓度及其化学计量比 总被引:9,自引:2,他引:9
对南昌大学前湖校区89种主要植物叶片的N、P浓度及其化学计量比进行了研究,结果表明:乔灌、常绿、针叶、种子、裸子和单子叶植物类群的N浓度分别低于相对应的草本、落叶、阔叶、蕨类、被子和双子叶植物类群,而C3和C4植物差异不显著;乔灌、常绿和裸子植物类群的P浓度含量分别低于相对应的草本、落叶和被子植物类群,而针叶和阔叶、蕨类和种子、单子叶和双子叶、C3和C4植物类群间差异不显著;乔木、阔叶、被子和双子叶植物类群叶片N/P分别高于相对应的灌草、针叶、裸子和单子叶植物类群,而常绿和落叶、蕨类和种子、C3和C4植物类群之间差异不显著.可见,不同类型植物对N和P的吸收利用存在差异,且对不同养分供应采取不同的适应对策.结合研究区土壤养分现状,建议优先选择常绿、针叶、裸子和单子叶植物类群作为城市园林植物. 相似文献
84.
The basic assumption of the analysis is that the stratigraphical change of relative abundance of the small mammal species is a phenomenon due to a certain number of environmental factors. In order to reveal these factors and to make some palaeoclimatic reconstructions the following approaches have been used: 1. Analysis of intrinsic structure of the initial data by using principal component analysis (PCA)—delimitation of recurrent groups of species and ordination of assemblages; 2. Extension backward in time of known ecological preference of taxa, forming a particular recurrent group; 3. Comparison of the results with the analysis of assemblages from “known”; (Holocene) environment. On the basis of ecological appearance of particular recurrent groups it is assumed that the main factors are temperatures and effective moisture. The reconstructed values for these environmental factors obtained on the basis of the Holocene recurrent groups of small mammals shows similarity to the recent climate in the area. 相似文献
85.
86.
《Comptes Rendus Palevol》2019,18(3):317-324
Terrestrial vertebrates from the karst filling in Cap d’Artrutx, situated in the extreme Southwest of Menorca (Balearic Islands, western Mediterranean) have yielded interesting information on the migration and extinction dynamics in the terrestrial island vertebrate faunas in Mallorca and Menorca between the late Pliocene and early Pleistocene. In this site, remains of the Menorcan giant tortoise (“Testudo” gymnesica Bate, 1914) and two mammals (Nesiotites sp. and Hypnomys sp.) have been found. The remains of the Menorcan giant tortoise represent the youngest record of this species and of the so-called second faunistic group of the island. The morphology and size of Nesiotites sp. are comparable to those of Nesiotites aff. ponsi Reumer, 1979 from the Plio-Pleistocene of Pedrera de S’Ònix (Mallorca) and Nesiotites meloussae Pons and Moyà, 1980 (= Nesiotites aff. ponsi sensu Pons-Monjo et al., 2012) from the lower Pleistocene of Binigaus (Menorca). Hypnomys sp. can belong to an archaic species not yet described. They represent the first evidence of the entrance of the third faunistic group, which originally evolved on the neighbouring island of Mallorca. This association is interpreted, therefore, as the first evidence of a faunal succession in the Plio-Pleistocene in the Balearic Islands. 相似文献
87.
Diversity of symbiotic bacteria associated with Bemisia tabaci (Homoptera: Aleyrodidae) in cassava mosaic disease pandemic areas of Tanzania 下载免费PDF全文
L.S. Tajebe D. Guastella V. Cavalieri S.E. Kelly M.S. Hunter O.S. Lund J.P. Legg C. Rapisarda 《The Annals of applied biology》2015,166(2):297-310
All Bemisia tabaci individuals harbour an obligate bacterial symbiont (Portiera aleyrodidarum), and many also harbour non‐essential facultative symbionts. The association of symbiotic bacteria with the various genetic groups of B. tabaci remains unknown for East Africa. This study aimed to assess any association between the various whitefly genetic groups and the endosymbionts they harbour; to investigate if a unique endosymbiont is associated with super‐abundant whiteflies, and to provide baseline information on endosymbionts of whiteflies for a part of East Africa. Whiteflies collected during surveys in Tanzania were genotyped and screened for the presence of the obligate and six secondary symbionts (SS): Rickettsia (R), Hamiltonella (H), Arsenophonus (A), Wolbachia (W), Cardinium (C) and Fritschea (F). The results revealed the presence of Mediterranean (MED), East Africa 1 (EA1), Indian Ocean (IO) and Sub‐Saharan Africa 1 (SSA1) genetic groups of Bemisia tabaci, with SSA1 further clustered into four sub‐groups: SSA1‐SG1, SSA1‐SG2, SSA1‐SG1/2 and SSA1‐SG3. F was completely absent from all of the whiteflies tested while R was always found in double or multiple infections. In general, no particular symbiont appeared to be associated with the super‐abundant SSA1‐SG1 B. tabaci, although A or AC infections were common among infected individuals. The most striking feature of these super‐abundant whiteflies, dominating cassava mosaic disease pandemic areas, was the high prevalence of individuals uninfected by any of the six SS tested. This study of the endosymbionts of B. tabaci in East Africa showed contrasting patterns of infection in crop and weed hosts. 相似文献
88.
纳西族和普米族的红细胞血型分布 总被引:2,自引:0,他引:2
调查了云南纳西族和普米族各104人的ABO、NMSs、Rh和P血型系统。结果表明,ABO血型系统中,纳西族和普米族有较高的基因频率r,分别为0.6082和0.6882,且基因频率p=q,纳西族均为0.1959,普米族均为0.1559。MNSw系统中两个民族都表现m〉n、s〉s,Ms〉Ns、MS〉NS,其中纳西族的基因频率在国内报道的相应值中是比较高的,且NS为零。 相似文献
89.
Yoshio Ogawa Atsuhiro Suda Kuniko Kusama-Eguchi Kazuko Watanabe Seiji Tokumasu 《Mycoscience》2005,46(6):343-351
Umbelopsis ramanniana is a well-known species in this genus. A characteristic morphological feature of this fungus is the remarkable variation
in the sporangiospore shape, which implies the genetic variations occur in the nucleotide sequences of the internal transcribed
spacer (ITS) regions of the nuclear ribosomal DNA (nrDNA) in the U. ramanniana isolates. The relationship between the variations of the sequences of the nrDNA ITS regions and those of the sporangiospore
morphology was investigated for 12 isolates of U. ramanniana collected in Europe. Neighbor-joining and parsimony analyses on the sequences suggested that these isolates split into three
groups. Precise examination of the morphology showed that the isolates of those respective groups were different from each
other in their sporangiospore shape. The present study implies at least three intraspecific groups exist in U. ramanniana and that the variations in the nucleotide sequences of the nrDNA ITS regions correlate well with those in the sporangiospore
shape in these intraspecific groups. 相似文献
90.
白蜡虫碱性磷酸酶功能基团的研究 总被引:9,自引:2,他引:9
白蜡ricerus pela雌成虫经匀浆,正丁醇抽提,硫酸铵分段盐析,SephadexG-150凝胶过滤等步骤,得到比活力为136.65U/mg蛋白酶制品,用苯甲基磺酰氟、N-溴代琥珀酰亚胺、三硝基苯磺酸、二巯基苏糖醇、对氯汞苯甲酸、琥珀酸酐、溴乙酸、碘乙酸等化学修饰剂在一定条件下选择修饰白蜡虫碱性磷酸酶的几种氨基酸残基,并测定酶活力变化。结果表明:苯甲基磺酰氟、N-溴代琥珀酰亚胺、三硝基苯磺酸、琥珀酸酐、二巯基苏糖醇的修饰能显著抑制酶的活力,活力的降低与修饰剂的浓度有关,氯汞苯甲酸、溴乙酸、碘乙酸的修饰对酶的抑制作用影响较小。初步认为:丝氨酸、赖氨酸和色氨酸残基是白蜡虫碱性磷酸酶的必需功能基团,部分二硫键也是酶的催化功能所必需的。 相似文献