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1.
This commentary introduces this special section on ‘‘the Effects of Bonds Between Human and Nonhuman Primates on Primatological Research and Practice.’’ The aim is to explore the different causes and consequences of bonding experiences between observers and observed in different primatological contexts. In the first contribution, Vitale asks what are the possible consequences of such bonding in behavioral primatology. Examples of beneficial consequences of this kind of relationship come fromstudies on cognitive abilities of great apes. Furthermore, an empathic attitude with the experimental animals leads to better care and attention toward individual welfare needs. Coleman discusses the particular case of nonhuman primates housed in research laboratories. Care-giving practices arediscussed in relation to scientific, ethical and emotional issues. Morimura et al. present the case of the first Japanese sanctuary for retiring chimpanzees from research where, in order to facilitate the social living of re-located chimpanzees, face-to-face interactions between caregivers and chimpanzees areessential. Asquith discusses the role of an thropomorphism, and proposes that this attitude can help to better understand the lives of primates, in more contextualized scenarios. In relation to this view, sheemphasizes how the term ‘‘primate culture’’ accords with some definition of the term ‘‘human culture.’’Fuentes, in his article asks whether national, class and ethnic characteristics can influence bonding between human and nonhuman primates, and calls for focused quantitative studies. Finally, Rose calls for the application of the concept of biosynergy, explained as promoting the formation of healthy and sustainable bonding relationships among living creatures. One of the most important aspects emerging from these papers is the need to better understand whether the issue of bonding in primatological studiescan be generalized to other areas of research such as conservation, behavior, captive care, or whether each of these disciplines needs to develop their own understanding of the effects of bonding in ‘‘producing science.’’  相似文献   

2.
The bonding strength between resin cement and posts is important for post and core restorations. An important method of improving the bonding strength is the use of various surface pretreatments of the post. In this study, the surfaces of zirconia (fiber) posts were treated by mechanical and/or chemical methods such as sandblasting and silanization. The bonding strength between the zirconia (fiber) post and the resin cement was measured by a push-out method after thermocycling based on the adhesion to Panavia F 2.0 resin cement. The zirconia and fiber posts exhibited different bonding strengths after sandblasting and/or silanization because of the different strengths and chemical structures. The zirconia post showed a high bonding strength of up to 17.1 MPa after a combined treatment of sandblasting and silanization because of the rough surface and covalent bonds at the interface. This effect was also enhanced by using 1,2-bis(trimethoxysilyl)ethane for the formation of a flexible layer at the interface. In contrast, a high bonding strength of 13.9 MPa was obtained for the fiber post treated by silane agents because the sandblasting treatment resulted in damage to the fiber post, as observed by scanning electron microscopy. The results indicated that the improvement in the bonding strength between the post and the resin cement could be controlled by different chemical and/or mechanical treatments. Enhanced bonding strength depended on covalent bonding and the surface roughness. A zirconia post with high bonding strength could potentially be used for the restoration of teeth in the future.  相似文献   

3.
"Florigen" is the name that Mikhail Chailakhyan coined in 1937 for the putative hormone regulating flowering. At this concept, plant physiologists arrived following early research concerning the effects of temperature and day length on the transition from vegetative to reproductive stages of plants. The existence of florigen was postulated on the experimental backgrounds involving i) the response of plants to inductive conditions; ii) transmission of a flowering stimulus by grafting; iii) extraction of this stimulus from induced plants. This experimental results showed the existence of florigen at least as concept because they always failed to offer the experimental evidence of its chemical existence. The myth of florigen persisted as long as the end of the Seventies, when physiologists began to consider flowering as a complex process in which various classes of hormones might variously interplay.  相似文献   

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Clique sizes for chimpanzee (Pan troglodytes) grooming and for human conversation are compared in order to test Robin Dunbar’s hypothesis that human language is almost three times as efficient a bonding mechanism as primate grooming. Recalculation of the data provided by Dunbar et al. (1995) reveals that the average clique size for human conversation is 2.72 whereas that of chimpanzee grooming is shown to be 2.18. The efficiency of human conversation and actual chimpanzee grooming over Dunbar’s primate grooming model (always one-to-one and a one-way interaction) is 1.27 and 1.25, respectively, when we take role alternation into account. Chimpanzees can obtain about the same efficiency as humans in terms of quantity of social interactions because their grooming is often mutual and polyadic. The fieldwork was supported by a grant from the International Scientific Research Program (07041138 to T. Nishida) of the Monbusho (Japanese Ministry of Education, Science, Sports, and Culture). Michio Nakamura is a research fellow at Japan Monkey Centre. He received his Master of Science degree from Kyoto University in 1996. He is carrying out research on the grooming behavior of chimpanzees at Mahale, Tanzania, for his doctorate.  相似文献   

6.
区域生态安全概念及评价体系的再认识   总被引:22,自引:3,他引:19  
王耕  王利  吴伟 《生态学报》2007,27(4):1627-1637
生态安全概念的提出已有十多年,但是至今还未有一个统一的定义。在“生态”涵义上的分歧导致了“生态安全”的许多种解释:强调生物(系统)与环境或与其他生物之间可持续发展关系的生态安全理解;强调生态环境涵义的生态安全理解;强调环境安全的生态安全理解;强调复合生态系统的生态安全理解。在生态安全评价体系上大多学者沿用“压力-状态-响应(P—S—R)”概念框架,但是通过本人实践和综合各位学者研究,反映出基于P—S—R框架的生态安全评价在生态安全状态研究上有余,安全趋势研究不足;总体研究有余,空间差异研究不足;现象研究有余,安全机理研究不足;结果理论性有余,实践指导性不足。在实际生产生活中人们更加关注的不仅是生态安全的现时状态,而是生态安全未来发展趋势。在安全科学中影响安全的因素是隐患,它在一定条件下触发或由量变累积到质变,安全状态就发生改变甚至突变。生态安全从诞生时起就孕育着各种隐患,而且无时无刻不受到隐患及危害的威胁,隐患因素的跨边界性传递作用又导致了生态安全空间差异性。因此生态安全是一个空间概念,区域生态安全是人与环境复合系统保障由于自然因素和人类活动或二者共同作用而产生的生态安全隐患对人类生态安全空间不构成威胁的状态或演变趋势的可能性。由于生态安全的动态性和空间性,仅仅基于“压力-状态-响应”(P—S—R)框架的状态评价研究是远不能全面客观解释与分析生态安全过程。为全面剖析生态安全的内涵,完善生态安全的理论,生态安全评价体系需要在不同区域的生态安全(特殊)机理研究,生态安全隐患研究,生态安全趋势预测研究,生态安全预警系统研究4个方面进一步深入地发展,使之更好地指导实践工作。  相似文献   

7.
A dominance hierarchy based on the outcome of agonistic encounters was found among male and female domestic cats. A female dominated over some males. The dominance concept is also discussed in terms of social bonding. The relationships among adult females were amicable, whereas adult males showed reciprocal tolerance. The flow of affiliative behaviour was directed mainly from females to one male of the group. The analysis of marking behaviour showed that this male sprayed urine and rubbed the perioral and cheek regions of the face on the objects of the environment at a higher rate than the other members of the group. Nevertheless, rubbing the perioral and cheek regions of the face on objects was not correlated to dominance rank, possibly because it has some function in social communication other than territorial defence against strangers. No relationships have been found between claw scratching, rolling on the ground and social rank, or between the former and other marking behaviour. It is concluded that claw scratching and rolling were not utilised to mark territory.  相似文献   

8.
In Biodemography, aging is typically measured and compared based on aging rates. We argue that this approach may be misleading, because it confounds the time aspect with the mere change aspect of aging. To disentangle these aspects, here we utilize a time-standardized framework and, instead of aging rates, suggest the shape of aging as a novel and valuable alternative concept for comparative aging research. The concept of shape captures the direction and degree of change in the force of mortality over age, which—on a demographic level—reflects aging. We 1) provide a list of shape properties that are desirable from a theoretical perspective, 2) suggest several demographically meaningful and non-parametric candidate measures to quantify shape, and 3) evaluate performance of these measures based on the list of properties as well as based on an illustrative analysis of a simple dataset. The shape measures suggested here aim to provide a general means to classify aging patterns independent of any particular mortality model and independent of any species-specific time-scale. Thereby they support systematic comparative aging research across different species or between populations of the same species under different conditions and constitute an extension of the toolbox available to comparative research in Biodemography.  相似文献   

9.
Utilizing Putnam's concept of bonding social capital, this article explores the under-researched topic of the history of migrant men's reproduction of social capital in Cardiff, Wales. Drawing upon a series of oral history interviews with a respected imam of more than fifty years, and informed by existing research on Muslim migrants, we explore both the advantages and disadvantages of community relationships between Yemeni men in relation to trust, reciprocity and interpersonal well-being. By examining these complex bonds, this article contributes to the literature on religious and ethnic social networks by challenging the assumption that migrants always benefit from social resources (Wilson 1978; Shah 2007), and offers an alternative account of religiously underpinned social capital to those of studies of majority ethnic Christians in North America (Smidt 2003). Uniquely, this article also points to the divergences between religious and ethnic capitals in the context of Yemeni migrants' social resources during 1939–1970.  相似文献   

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Contemporary research indicates that religious institutions can play bonding and bridging roles in the lives of immigrants, strengthening the bonds within immigrant groups while simultaneously connecting immigrants to the wider society. The majority of this research focuses on religious institutions in US cities with long histories of immigration and sizable immigrant populations. This article examines the role of religious institutions in the lives of refugees living in a city with a small, but rapidly growing immigrant population. Evidence from interviews with Catholic and Muslim refugees and participant observation at two houses of worship suggests that the functions of religious institutions differ for refugees from majority and minority religious traditions. Catholic refugees use their church for bonding and bridging purposes, while Muslim refugees use their mosque primarily for bonding purposes.  相似文献   

12.
The phospholipid acyl chain composition and order, the hydrogen bonding, and properties of the phospholipid headgroup all influence cholesterol/phospholipid interactions in hydrated bilayers. In this study, we examined the influence of hydrogen bonding on sphingomyelin (SM) colipid interactions in fluid uni- and multilamellar vesicles. We have compared the properties of oleoyl or palmitoyl SM with comparable dihydro-SMs, because the hydrogen bonding properties of SM and dihydro-SM differ. The association of cholestatrienol, a fluorescent cholesterol analog, with oleoyl sphingomyelin (OSM) was significantly stronger than its association with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, in bilayers with equal acyl chain order. The association of cholestatrienol with dihydro-OSM, which lacks a trans double bond in the sphingoid base, was even stronger than the association with OSM, suggesting an important role for hydrogen bonding in stabilizing sterol/SM interactions. Furthermore, with saturated SM in the presence of 15 mol % cholesterol, cholesterol association with fluid dihydro-palmitoyl SM bilayers was stronger than seen with palmitoyl SM under similar conditions. The different hydrogen bonding properties in OSM and dihydro-OSM bilayers also influenced the segregation of palmitoyl ceramide and dipalmitoylglycerol into an ordered phase. The ordered, palmitoyl ceramide-rich phase started to form above 2 mol % in the dihydro-OSM bilayers but only above 6 mol % in the OSM bilayers. The lateral segregation of dipalmitoylglycerol was also much more pronounced in dihydro-OSM bilayers than in OSM bilayers. The results show that hydrogen bonding is important for sterol/SM and ceramide/SM interactions, as well as for the lateral segregation of a diglyceride. A possible molecular explanation for the different hydrogen bonding in SM and dihydro-SM bilayers is presented and discussed.  相似文献   

13.
Building on the planning efforts of the RCN4GSC project, a workshop was convened in San Diego to bring together experts from genomics and metagenomics, biodiversity, ecology, and bioinformatics with the charge to identify potential for positive interactions and progress, especially building on successes at establishing data standards by the GSC and by the biodiversity and ecological communities. Until recently, the contribution of microbial life to the biomass and biodiversity of the biosphere was largely overlooked (because it was resistant to systematic study). Now, emerging genomic and metagenomic tools are making investigation possible. Initial research findings suggest that major advances are in the offing. Although different research communities share some overlapping concepts and traditions, they differ significantly in sampling approaches, vocabularies and workflows. Likewise, their definitions of ‘fitness for use’ for data differ significantly, as this concept stems from the specific research questions of most importance in the different fields. Nevertheless, there is little doubt that there is much to be gained from greater coordination and integration. As a first step toward interoperability of the information systems used by the different communities, participants agreed to conduct a case study on two of the leading data standards from the two formerly disparate fields: (a) GSC’s standard checklists for genomics and metagenomics and (b) TDWG’s Darwin Core standard, used primarily in taxonomy and systematic biology.  相似文献   

14.
张德兴 《生物多样性》2016,24(9):1009-886
生物学家通常认为物种是生命多样性的基本单位。然而, 尽管近一个世纪以来生物学家们不断地讨论物种概念问题, 但到目前为止仍然难以形成共识。大多数生物学家关注如何定义物种主要是因为它有非常重要的实践意义, 所以, 不同学者提出的物种概念在很大程度上是基于实践应用上的可操作性, 并且其视角难免受其专业见地以及对形成新物种的进化过程的认识所影响。物种代表了进化过程的一个阶段, 而且不同的“物种”可能处于物种形成这个进化过程的不同阶段。鉴于“定义”实际上是一种类似协议的约定或界定, 任何定义都是一种带有局限性的概括, 因此我们可能很难建立一个与分类实践中千变万化的情况都能完全匹配协调的物种定义。已经提出来的那些物种概念或定义都有其合理性, 但是也没有一个是完美无缺的。认识到这一点很重要, 否则就可能会因为固执地坚持某一特定的物种概念而在物种界定和进化研究中自觉或不自觉地引入错误甚至制造混乱。  相似文献   

15.
An algorithm is presented to identify peptide chain turns from X-ray-elucidated co-ordinate data. Chain turns are those regions in a globular protein where the backbone is folded back upon itself. The concept of a turn is important both because turns constitute recognizable structural units in proteins and because turns are situated at the solvent-accessible surface of the molecule.Current algorithms for turn identification are highly operational in character, often finding false turns and omitting actual ones. The algorithm presented here uses only the C-alpha co-ordinates for every residue in the protein. No other information of any kind is required, and notions about hydrogen bonding at these loci are irrelevant to the geometric nature of the argument. In this sense, the algorithm provides an objective criterion for the recognition of turns as strictly structural components in proteins.The algorithm is used to find the turns in a test set of proteins. Results of this application are in excellent agreement with visual turn identification from physical models.  相似文献   

16.
A useful concept that can be invoked to resolve complex bioethical issues is that of moral status (or, human dignity). In this article, we apply this concept to dead human bodies in order to support our view that research on such bodies is permissible. Instead of drawing from salient Western theories of human dignity that account for it by appeals to autonomy or rationality, we will base our investigation on emerging conceptions in African theories of moral status as articulated by Thaddeus Metz and Munamato Chemhuru. Our conclusion is that neither of these theories of moral status, one secular, and the other religious, can accommodate the intuition that we have direct duties of respect towards such bodies because, in relation to Metz's conception, they lack the capacity to enter into social relationships while on Chemhuru's conception, dead bodies appear not to have any meaningful purpose within the hierarchy that captures the ontological systems that determine such status. Consequently, we argue that our analysis provides support for the use of unclaimed cadavers in training and research in medical institutions.  相似文献   

17.
Historically, two main concepts guided research into possible mechanisms of light-induced atomic rearrangements in oxygenic photosynthesis: Photodecomposition of CO2 and photodecomposition of water. Both concepts envisioned photoinduced transfers of cumbersome whole atoms and not, as is currently held, photoinduced electron transfers. Early proposals for light-induced electron transfers were relegated to obscurity because they were speculative ideas, not supported by meaningful experimental findings and tied to hypothetical and ephemeral schemes. The concept of photoinduced rearrangements of whole atoms rather than electrons was so well entrenched that it was even invoked to explain their findings by the discoverers of the Hill reaction and cyclic photophosphorylation. The light-induced electron flow concept gained acceptance in photosynthesis research only with the discovery of non-cyclic photophosphorylation in which ATP formation is coupled with electron transport to ferredoxin/NADP+ or to artificial substitutes like ferricyanide.  相似文献   

18.
何思源  闵庆文 《生态学报》2022,42(15):6041-6053
以国内外文献、报告、规划为原始材料,以"保护兼容"一词为核心,结合其使用语境,系统阐述在自然保护话语由"堡垒式"转向"社区保护"时,随着自然保护地功能与管理发生变化,人类活动的保护兼容性如何被重新发现并在自然保护实践中助力生物多样性保护。研究发现,"保护兼容"理念充分体现在景观尺度的土地利用连续体上;在生产性景观视角下乡村土地利用和传统农业系统进入自然保护领域;"保护兼容"理念以土地利用为基础下沉到乡村社区的资源管理、生计发展等多类型活动,以各种保护倡议和项目实现,并在发展中国家和发达国家呈现出不同特征。"保护兼容"理念既进行尺度扩展,探索区域内、跨行政区域乃至国家间多利益相关方参与、多类型土地利用贡献于自然保护扩展,也进行尺度下沉,倡导基于本土价值实现全球价值的保护理念。研究提出,全球在生物多样性保护中要进一步重视生产性景观和农业生物多样性保护,而发展中国家面对全球生物多样性保护紧迫目标时,需要坚持社区主体性和在保护实践中的主动性。  相似文献   

19.
There may be different causes of failures in bone; however, their origin generally lies at the lowest level of structural hierarchy, i.e., at the mineral-collagen composite. Any change in the nanostructure affects the affinity or bonding effectiveness between and within the phases at this level, and hence determines the overall strength and quality of bone. In this study, we propose a novel concept to assess change in the nanostructure and thereby change in the bonding status at this level by revealing change in the orientation distribution characteristics of mineral crystals. Using X-ray diffraction method, a parameter called Degree of Orientation (DO) has been quantified. The DO accounts for the azimuthal distribution of mineral crystals and represents their effective amount along any direction. Changes in the DOs in cortical bone samples from bovine femur with different preferential orientations of mineral crystals were estimated under external loads. Depending on the applied loads, change in the azimuthal distribution of the DOs and the degree of reversibility of the crystals was observed to vary. The characteristics of nanostructural change and thereby possible affect on the strength of bone was then predicted from the reversible or irreversible characteristics of distributed mineral crystals. Significant changes in the organization of mineral crystals were observed; however, variations in the applied stresses and elastic moduli were not evinced at the macroscale level. A novel concept to assess the alteration in nanostructure on the basis of mineral crystals orientation distribution has been proposed. The importance of nanoscale level information obtained noninvasively has been emphasized, which acts as a precise tool to estimate the strength and predict the possible fracture risks in bone.  相似文献   

20.
John Gray 《Anthrozo?s》2014,27(2):219-234
This paper analyzes the phenomenon called hefting of sheep onto the landscape of hill sheep farms in the Scottish Borders. It is based upon data collected during extended periods of ethnographic fieldwork beginning in 1981 and continuing to the present. Hefting is the term used by sheep farmers for the natural tendency of hill sheep to graze, remain, and bond onto specific areas of the landscape without the need for fencing. The herding practices of hill sheep farms appropriate hefting in flock management and breeding. The analysis of hefting makes two contributions to understanding human–animal relations. First, because the of the centrality of territorial bonding, hefting makes explicit that we should always be ready to include a third dimension—place and emplacement—in understanding human–animal relations. Second, drawing on Haraway's concept of “becoming with,” hefting and herding demonstrate the fundamentally relational character of human–animal–place relations.  相似文献   

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