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1.
The Public Health Nutrition (PHN) community categorizes dietary-related chronic illnesses as "noncommunicable," fixing these afflictions within individual bodies where they are best managed by individual choices. Yet within clinical encounters in Guatemala, nutritionists and patients treat eating and dieting as relational, transmissible practices. Patients actively seek nutritionists' care, asserting their self-care attempts have failed and they need support from others; nutritionists meanwhile develop treatment plans that situate "personal choice" as lying outside the control of a solitary individual. This article moves between international policy-pedagogy and patient-nutritionist interactions to examine forms of personhood, responsibility, and rationalities of choice present in body weight-management practices in Guatemala. Although nutrition discourses might appear to exemplify how institutional (bio)power manifests through internalized self-monitoring and preoccupation for one's own self, I argue that within the lived experiences of "nutrition-in-action," the self-body of the patient becomes broadly conceived to include the nutritionist, the family, and the broader community.  相似文献   

2.
Evolutionary theory of senescence emphasizes the importance of intense selection on early reproduction owing to the declining force of natural selection with age that constrains lifespan. In humans, recent studies have, however, suggested that late-life mortality might be more closely related to late rather than early reproduction, although the role of late reproduction on fitness remains unclear. We examined the association between early and late reproduction with longevity in historical post-reproductive Sami women. We also estimated the strength of natural selection on early and late reproduction using path analysis, and the effect of reproductive timing on offspring survival to adulthood and maternal risk of dying at childbirth. We found that natural selection favoured both earlier start and later cessation of reproduction, and higher total fecundity. Maternal age at childbirth was not related to offspring or maternal survival. Interestingly, females who produced their last offspring at advanced age also lived longest, while age at first reproduction and total fecundity were unrelated to female longevity. Our results thus suggest that reproductive and somatic senescence may have been coupled in these human populations, and that selection could have favoured late reproduction. We discuss alternative hypotheses for the mechanisms which might have promoted the association between late reproduction and longevity.  相似文献   

3.
自然资本流变及其对生态系统服务价值的演变路径   总被引:1,自引:0,他引:1  
刘颂  戴常文 《生态学报》2021,41(3):1189-1198
生态系统服务价值化是将生态系统惠益于人类社会的价值进行量化,以评估生态系统服务状态,便于生态系统监测和管理。自然资本是生态系统服务的来源,结合自然资本视角进行生态系统服务价值化,其成果有利于提高生态系统保护政策制定的精准性和统筹力,有利于创新生态系统服务评估方法。通过梳理自然资本概念的缘起与发展过程,认为自然资本经历了"同义指代"、"边界明晰"、"多领域交汇"和"隐喻多义"四个阶段逐步丰富的过程。当今针对自然资本研究的三种主流视角,即将自然资本视为"产生经济价值的资产"、"产生服务流的存量"和"金融资本"为生态系统服务的价值化提供了多种途径。生态系统服务价值化的过程要体现可持续发展的基本目标,保证自然资本的稳定,维持人类社会代际公平。以此为前提,鼓励生态系统价值化视角的多样性。价值化途径应关注生态系统服务的时空动态变化、多种服务协同作用和供需权衡。生态系统服务价值化是自然资本金融杠杆化的推手,应警惕有可能带来的金融风险和生态风险。  相似文献   

4.
Body size of many animals increases with increasing latitude, a phenomenon known as Bergmann's rule (Bergmann clines). Latitudinal gradients in mean temperature are frequently assumed to be the underlying cause of this pattern because temperature covaries systematically with latitude, but whether and how temperature mediates selection on body size is unclear. To test the hypothesis that the "relative" advantage of being larger is greatest at cooler temperatures we compare the fitness of replicate lines of the seed beetle, Stator limbatus, for which body size was manipulated via artificial selection ("Large,"Control," and "Small" lines), when raised at low (22 degrees C) and high (34 degrees C) temperatures. Large-bodied beetles (Large lines) took the longest to develop but had the highest lifetime fecundity, and highest fitness (r(C)), at both low and high temperatures. However, the relative difference between the Large and Small lines did not change with temperature (replicate 2) or was greatest at high temperature (replicate 1), contrary to the prediction that the fitness advantage of being large relative to being small will decline with increasing temperature. Our results are consistent with two previous studies of this seed beetle, but inconsistent with prior studies that suggest that temperature-mediated selection on body size is a major contributor to the production of Bergmann clines. We conclude that other environmental and ecological variables that covary with latitude are more likely to produce the gradient in natural selection responsible for generating Bergmann clines.  相似文献   

5.
In this article, I examine the meaning of natural bodies and natural births in contemporary midwifery in Canada and explore the impact of these central concepts on the embodied experiences of pregnant and birthing women. The ideal of a natural birth has been used as a successful rhetorical strategy in scholarly and popular feminist works on childbirth to counter and critique the predominant biomedical or "technocratic" model of the pregnant and birthing body as inherently problematic and potentially dangerous to the fetus. Contemporary Canadian midwifery--which only as recently as 1994 made a historic transition from a grassroots social movement to a full profession within the public health care system--continues to work discursively through the idiom of nature to affect women's knowledge and experience of their bodies and selves in pregnancy and birth. However, my key finding in this ethnographic study, which focused primarily on midwifery in the province of Ontario in the years following professionalization, is that natural birth is being redefined by the personal, political, and pragmatic choices of midwives and their clients. I argue that the construction, negotiation, and experience of natural birth in contemporary midwifery both reflects and promotes a fundamental shift away from essentialized understandings as it makes room for biomedical technology and hospital spaces, underpinned by the midwifery logics of caring and choice. Natural birth in this context also carries important cultural messages--gender expectations--that posit women as persons and bodies as naturally competent and knowing.  相似文献   

6.
目的:探讨疤痕子宫妊娠妇女经产道分娩的可行性、安全性和相关危险因素。方法:选择疤痕子宫妊娠妇女120例,根据分娩方式的不同分为剖宫产组(80例)与自然分娩组(40例),观察再次剖宫产的原因与两组的预后情况。结果:再次剖宫产的指征主要为疤痕子宫(患者拒绝试产)、产程异常、胎儿窘迫、前置胎盘等。自然分娩组的产时出血量明显少于剖宫产组(P0.05),产后出血与产后感染发生率也均明显低于剖宫产组(P0.05)。两组的5分钟Apgar评分对比差异无统计学意义,但自然分娩组新生儿黄疸与新生儿湿肺发生情况明显低于剖宫产组(P0.05)。自然分娩组的分娩满意度为97.50%,剖宫产组为83.75%,自然分娩组明显高于剖宫产组(P0.05)。结论:疤痕子宫妊娠妇女经产道分娩可行性好,能减少对于产妇与新生儿的影响,安全性佳,但也要根据产妇的实际情况进行具体选择。  相似文献   

7.
D. E. Stewart 《CMAJ》1982,127(8):713-716
As natural childbirth has become more popular, new prenatal training groups have developed, some of which are committed to only one method of dealing with labour and delivery. This paper describes five women and four men who sought psychiatric treatment within 6 months of attempted natural childbirth that did not proceed as planned. Their symptoms included depression, anxiety, obsessive-compulsive behaviour, phobic symptoms, and marital and sexual problems. Thus, natural childbirth, although undoubtedly beneficial in most instances, is not suitable for all deliveries and may occasionally have adverse effects. Prenatal programs should emphasize an individual, flexible approach to labour and delivery and should present the possibility of the need for analgesia, anesthesia or obstetric intervention in a positive light.  相似文献   

8.
This paper presents the results of a larger study conducted among Southern Sudanese refugees in Cairo, Egypt. "Illness talk" and body metaphors are the focus of the present work, which is based mainly on an analysis of the illness narratives of people attending a church-run medical clinic. The findings suggest that refugees use certain narrative styles in discussing their illnesses that highlight the interconnection of bodily ills and refugee-related trauma. The refugees narrated the histories of their illnesses in terms consistent and coterminous with their refugee histories, and articulated illness causes in terms of threatening assaults on their sense of self as human beings and as part of a distinct community and culture. The use of embodied metaphors to understand and cope with their current and past traumatic experiences was echoed in narratives that were nonillness related. Metaphors such as "the heart," "blood," and "body constriction" were consistently used to discuss social and cultural losses. Understanding the role that the body plays in experience and communication within a given cultural context is crucial for physicians and others assisting refugees.  相似文献   

9.
In this article, I focus on unintended pregnancy as a means to interrogate the intersections of abortion and prenatal discourses in the United States, and the ways in which these discourses assume certain kinds of moral, liberal subjects. Using media material, congressional legislation, public health policy, and ethnographic data from South Florida (2004-06), I trace how these discourses assume that women will behave in "rational," "responsible" ways to plan their reproductive futures, and how these assumptions intersect with Haitian women migrants' lived experiences in South Florida. My research illustrates how decisions about family planning are situated within particular local moral worlds, where gender relations, religion, power, and desires for children inform women's everyday lives.  相似文献   

10.
11.
In the present study, the ADL index for the partially dependent older people (Demura et al., 1999) was applied to 218 bedridden (BED), 466 partially dependent (PD) and 245 independent living (IL) people in older groups. The purposes of this study were to clarify the meaning of the evaluation of this index and to examine how ADL items are useful in determining each older group. It is suggested that a perfect score with our ADL index means independent living level, and a score of zero means bedridden level. The results of discriminant analysis indicated that four items with low-difficulty, such as "eating," "going to the toilet," "tossing about in bed" and "writing," are useful in determining if the PD is becoming bedridden. While five items with high-difficulty, such as "putting on slacks," "putting on trousers," "standing up from a sitting posture," "going up stairs" and "washing the whole body," are useful in determining if the PD is becoming independent living. Furthermore, it is inferred that the possibility of falling into a bedridden situation increases when the total score is 5 or less, while the functional level is close to independent living when the total score is 13 or more. These findings make clear the meaning of the evaluation of our ADL index. Furthermore, the functional level of older population may be screened using evaluation of total and item scores of this ADL index.  相似文献   

12.
In the course of interviews with Israeli women who had recently been treated for breast cancer, we found that our informants tended to offer us "treatment narratives" rather than, or sometimes in addition to, the "illness narratives" made famous by Arthur Kleinman. For the women we interviewed, treatment narratives constitute verbal platforms on which to explore what it means to be human during a period in which one's body, spirit, and social identity are undergoing intense transformations. A central theme in these narratives is the Hebrew word yachas, loosely translated as "attitude," "attention," or "relationship." The women consistently contrasted the good yachas of medical staff who treated them "like humans" or like "real friends" with the bad yachas of staff who treated them like numbers, machines, or strangers. We argue that the women used language (in various contexts) as a means of resisting the medical culture's pattern of treating patients as "nonhumans."  相似文献   

13.
The origin of modern man is a highly debated issue that has recently been tackled by using mitochondrial DNA sequences. The limited genetic variability of human mtDNA has been explained in terms of a recent common genetic ancestry, thus implying that all modern-population mtDNAs originated from a single woman who lived in Africa less than 0.2 Mya. This divergence time is based on both the estimation of the rate of mtDNA change and its calibration date. Because different estimates of the rate of mtDNA evolution can completely change the scenario of the origin of modern man, we have reanalyzed the available mitochondrial sequence data by using an improved version of the statistical model, the "Markov clock," devised in our laboratory. Our analysis supports the African origin of modern man, but we found that the ancestral female from which all extant human mtDNAs originated lived in a time span of 0.3-0.8 Mya. Pushing back the date of the deepest root of the human implies that the earliest divergence would have been in the Homo erectus population.  相似文献   

14.
Compositional constraints and genome evolution   总被引:31,自引:0,他引:31  
  相似文献   

15.
In this article, I draw on anthropological and feminist scholarship on the body and the nature/culture divide as a framework for understanding the place of surrogate mothers in a conceptual ideology that connects motherhood with nature. I explore links between the medicalization of childbirth in Israel and the personal agency of surrogate mothers as relayed through interviews. Taking the patriarchal context of the Israeli surrogacy law of 1996 into consideration, I underscore surrogates' imaginative use of medical metaphors as tools for the subversion of surrogacy's threatening social connotations. By redefining the surrogate body as "artificial" and locating "nature" in the commissioning mother's body, surrogates adopt medical rhetoric to transform surrogacy from a transgressive act into an alternative route toward achieving normative Israeli national reproductive goals.  相似文献   

16.
A new heterotrophic flagellate (Andalucia godoyi n. gen. n. sp.) is described from soil. Earlier preliminary 18S rRNA analyses had indicated a relationship with the phylogenetically difficult-to-place jakobid Jakoba incarcerata. Andalucia godoyi is a small (3-5 mum) biflagellated cell with a ventral feeding groove. It has tubular mitochondrial cristae. There are two major microtubular roots (R1, R2) and a singlet root associated with basal body 1 (posterior). The microtubular root R1 is associated with non-microtubular fibres "I,"B," and "A," and divides in two parts, while R2 is associated with a "C" fibre. These structures support the anterior portion of the groove. Several features of A. godoyi are characteristic of jakobids: (i) there is a single dorsal vane on flagellum 2; (ii) the C fibre has the jakobid multilaminate substructure; (iii) the dorsal fan of microtubules originates in very close association with basal body 2; and (iv) there is no "R4" microtubular root associated with basal body 2. Morphological analyses incorporating the A. godoyi data strongly support the monophyly of all jakobids. Our 18S rRNA phylogenies place A. godoyi and J. incarcerata as a strong clade, which falls separately from other jakobids. Statistical tests do not reject jakobid monophyly, but a specific relationship between Jakoba libera and J. incarcerata and/or A. godoyi is rejected. Therefore, we have established a new genus Andalucia n. gen. with the type species Andalucia godoyi n. sp., and transfer Jakoba incarcerata to Andalucia as Andalucia incarcerata n. comb.  相似文献   

17.
Laboratory studies have revealed a significant "cost of mating" to Drosophila melanogaster females in the form of reduced longevity. The effect is attributable to nonsperm components of the ejaculate. Female D. melanogaster are known to mate up to six times in nature, and given that they do not typically remate daily, it raises the question as to the extent to which the longevity of wild mated females is reduced. Here I addressed this question by comparing the longevity of wild virgin females, collected as they emerged from rotting fruit, to the longevity of randomly collected mature females at the same site. Because the randomly collected females all were inseminated and were fully pigmented at the time of collection, they already were older than the virgins when the experiment began. Contrary to expectations from laboratory studies, the older, mated females lived significantly longer than the virgins. Rather than a "cost of mating," there appears to be a "cost of virginity" to female D. melanogaster in the wild.  相似文献   

18.
人工饲养下亚河豚的行为生物学研究   总被引:1,自引:1,他引:0  
本文报道了2头雄性亚河豚“Vater”和“Baby”的各种行为。研究表明,饲养池的大小直接影响豚的行为;由于亚河豚和白豚生存的环境不同,导致了它们身体结构的差异,从而表现出不同的行为方式。  相似文献   

19.
A N Stroud  R Nathan  S Harami 《In vitro》1975,11(2):61-68
Early chromatin condensation in interphase cells (G1) of human peripheral blood lymphocytes has been induced without virus or cell fusion by exposure to allogeneic or xenogeneic mitotic cells. The event, although similar in some ways to the phenomenon described as "premature chromosome condensation," "chromosome pulverization," and "prophasing," differs in that it does not require the presence of viruses and cell fusion before mitosis proceeds in the G1 cell. Early chromatin condensation in interphase cells induced by mitotic cells only, consists of chromatids in the early or late G1 phase of the cell cycle that are not pulverized or fragmented at mitosis. Some of the chromosomes are twice as long as the metaphase chromosomes and exhibit natural bands. Almost twice as many of these bands are produced as by trypsin treatment of metaphase chromosomes. The nuclear membrane is intact and nucleoli are present, to which some chromosomes are attached. The DNA content of the precocious chromosomes in G1 is half the amount of the metaphase complement.  相似文献   

20.
A range of autotrophic and heterotrophic enrichment cultures were established to determine the cultural bacterial diversity present in samples obtained from the acidic runoff of a chalcocite overburden heap and from laboratory-scale (1- to 4-liter) batch and continuous bioreactors which were being used for the commercial assessment of the bioleachability of zinc sulfide ore concentrates. Strains identified as Thiobacillus ferrooxidans, Thiobacillus thiooxidans, "Leptospirillum ferrooxidans," and Acidiphilium cryptum were isolated from both the natural site and the batch bioreactor, but only "L. ferrooxidans," a moderately thermophilic strain of T. thiooxidans, and a moderately thermophilic iron-oxidizing bacterium could be recovered from the continuous bioreactor running under steady-state conditions. Sequence analysis of the 16S rRNA genes of 33 representative strains revealed that all of the strains were closely related to strains which have been sequenced previously and also confirmed the phylogenetic diversity of bacteria present in bioleaching environments.  相似文献   

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