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1.
This essay explores the phenomenon known as ‘orphaned wells’, meaning unprofitable oil and gas wells (‘legacy wells’) that have become disentangled from their corporate owners owing to insolvency, or owing to a failure to comply with local regulations. Drawing from an ethnographic example of a near-insolvent oil and gas corporation in Alberta, Canada, and its strategies of refinancing, the essay explores how value creation and the moral force of the obligation to create a financial return give rise to a ‘durational ethics’ that shapes corporate and financial performativities and prolongs the ‘life’ of legacy oil and gas assets. Legacy assets, understood as potential orphans, are thus caught up in a lively corporate practice of asset circulation and recombination often deployed by producers for the moral work of ‘cleaning balance sheets’. This essay calls for ‘thinking with orphans’ to recognize the competing ethical registers which produce them in addition to the growing need for responsibility and corporate care for legacy oil and gas assets.  相似文献   

2.
Orphans who lack household or community support face significant socio-economic disadvantages. In particular, they are at greater risk of malnutrition and stunting in developing countries. Children who have no living parents, also called double orphans, are most likely to require support from extended families or public institutions. This paper explores how WASH infrastructure, and public health and social services relate to stunting. It is one of the first studies to analyse these factors with a specific focus on double orphans, who tend to live in under-serviced areas with high stunting rates and poor access to public resources. We collate a cross sectional spatial dataset with local child stunting rates from 2013, rates of double orphanhood, private household resources, and public services from 2011 for South Africa, a country where the HIV/AIDS pandemic has led to high rates of double orphanhood. We estimate spatial econometric models that account for unobserved regional shocks and measurement bias, but which do not address other biases. Our results show that high stunting rates, particularly in areas with high proportions of double orphans, overlap strongly with poor provision of WASH and the availability of household resources. By contrast, other softer services accessed outside the home, such as access to health, social welfare and early childhood development facilities are not correlated with stunting in the same way. WASH is more strongly related to reduced stunting when infrastructure covers larger geographic areas and with the combined use of services from adjacent areas. This occurs because of economies of scale in provision and preventing transmission of disease across regions. Policy makers can explore the option to reduce stunting by expanding geographic networks of WASH service delivery into under-serviced areas where double orphans tend to locate.  相似文献   

3.
免耕高留茬抛秧对稻田土壤肥力和微生物群落的影响   总被引:7,自引:0,他引:7  
通过大田试验,研究了不同秸秆还田和耕作方式(免耕+秸秆还田、免耕、常耕+秸秆还田、常耕)对稻田不同层次土壤肥力和主要微生物类群数量的影响.结果表明:上层土壤中,免耕+秸秆还田处理的有机质含量分别比免耕、常耕+秸秆还田和常耕处理高5.33、2.79和5.37 g·kg-1;全氮、全磷、全钾、碱解氮、速效磷和速效钾含量也均以免耕+秸秆还田处理最高,免耕和常耕+秸秆还田处理次之,常耕处理最低.下层土壤中,各肥力指标以常耕+秸秆还田处理较高.秸秆还田各处理微生物类群数量较高,上层土壤以免耕+秸秆还田处理的细菌、真菌和放线菌数量最高,成熟期其纤维分解强度分别比常耕+秸秆还田、免耕和常耕处理高26.44%、79.01%和98.15%;下层土壤以常耕+秸秆还田处理的细菌、真菌和放线菌数量最高.免耕+秸秆还田处理的土壤养分和微生物呈表层富集特征.细菌、放线菌和纤维分解强度与土壤肥力各指标呈显著或极显著正相关关系.  相似文献   

4.
Recent anthropological scholarship on marriage in South Asia has chronicled a shift towards companionate marriage, with ideals of companionate conjugality becoming central to middle-class self-representations. However, the role of child-bearing and fertility within these marriages, as emerging life projects related to new family ideals, has not received much attention, even as literature on India has recorded extensive family concern with fertility. In this article, I focus on the endocrine disorder polycystic ovary syndrome (PCOS) – one of the leading causes of female infertility world-wide – to examine emerging conceptions of fertility and intimate modernities among the urban middle class in India. I argue that a comparatively limited concern with fertility forms a part of this class's self-representations and practices of distinction. Such attitudes to fertility, enabled by new orientations towards medical risk and ideals of companionate marriage, also function as markers of the emerging ‘modern’ subjectivity of this class.  相似文献   

5.
Inspired by the fertility and climate change-mitigation properties of the so-called Amazonian Dark Earths (ADEs), soil science has devised a technoscientific replica, a soil amendment known as biochar, intended to improve agricultural sustainability and carbon storage in the biosphere. Drawing on fieldwork with Afroindigenous horticulturalists, this article shows, however, that the activation of these soils’ vibrant ecology responds to looping, carbonic, and socially mediated forms of human and other-than-human corporeal interplay. With an ethnography of swidden horticulture in Amazonia, I propose the notion of ‘somatosoils’ to consider that the fertility and other metabolic properties of ADEs might be located not in the soil, but in the relations between the earth's bodies and the specific human gestures that stimulate these soils’ inner life.  相似文献   

6.
Improvement of reproduction in dairy cows has become a major challenge in dairy production. We have recently shown that dairy cows carrying the ‘fertil−’ haplotype for one quantitative trait locus (QTL), affecting female fertility and located on the bovine chromosome 3, had a significantly lower conception rate after the first artificial insemination than cows carrying the ‘fertil+’ haplotype. The objective of this paper was to study other phenotypic modifications linked to this QTL. In the present study, 23 ‘fertil+’ and 18 ‘fertil−’ cows were characterized for live weight, milk production, food intake, eating behaviour and plasma metabolites. These parameters were measured during the first lactation, from calving to 40 weeks postpartum (wkpp). In the first 7 weeks of lactation, ‘fertil+’ primiparous cows had a significantly higher live BW and milk production than ‘fertil−’ cows. Dry matter intake tended to be slightly higher for ‘fertil+’ than for ‘fertil−’ primiparous cows in this period. However, energy balance was similar for the two haplotypes in the whole lactation, except in the first wkpp, and consequently, could not explain their different fertility. The major observation concerned the eating behaviour. ‘Fertil+’ primiparous cows had a significantly lower eating rate than ‘fertil−’ cows during the 40 weeks of lactation. In parallel, ‘fertil+’ cows spent significantly more time at the feeder for a similar number of visits than ‘fertil−’ cows. Furthermore, no differences in plasma concentrations of non-esterified fatty acids and insulin were observed between the two haplotypes. Plasma glucose was significantly lower in ‘fertil+’ than in ‘fertil−’ cows in the second wkpp. Taken together, our results show that ‘fertil+’ and ‘fertil−’ dairy cows, with different fertility, have also different eating behaviour without any variation in energy balance, except in the first week of lactation.  相似文献   

7.
Two sets of three replicate lines of Drosophila melanogaster were artificially selected by reproduction at either a ‘young’ or an ‘old’ age. The pure lines, the hybrids between the lines within a selection regimen and the base stock from which the lines were derived were compared for longevity, early and late fertility, development time, larval viability and adult thorax length. Comparison of hybrid with pure lines showed some evidence for inbreeding depression in the lines from both selection regimes. Comparison of hybrid lines with the base stock did not provide evidence for any trade-off in either males or females between early fertility on the one hand and late life fertility and longevity on the other. Nor was there any clear evidence of a trade-off between pre-adult and adult fitness components. There was evidence of inadvertent selection for rapid development in both selection regimens, especially in the females of the ‘young’ lines, and this complicated the interpretation of the responses and correlated responses to selection. An improvement in adult performance in the ‘old’ line males relative to the base stock appeared to be attributable to reversal of mutation accumulation. Comparison of the hybrid ‘young’ and ‘old’ lines with the base stock did not support the idea that the superior longevity and late life fertility of the ‘old’ lines relative to the ‘young’ lines could be accounted for by the effects of mutation accumulation in the ‘young’ lines. The results point to the need to compare selected lines with their base stock when deducing responses and correlated responses to selection and to avoid unintentional selection. In this type of experiment, larval density should be standardized during selection, and adults should not be under pressure for rapid maturation.  相似文献   

8.
Thompson , Maxine M. (U. California, Davis.) Cytogenetics of Rubus. II. Cytological studies of the varieties ‘Young,’ ‘Boysen’ and related forms. Amer. Jour. Bot. 48(8): 667–673. Illus. 1961.—Chromosome numbers are given for the trailing blackberry varieties, ‘Young’ (2n = 49), ‘Boysen’ (2n = 49), ‘Nectar’ (2n = 49) and for related forms which include the parents of ‘Young,’ ‘Phenomenal’ (2n = 42) and ‘Mayes’ (2n = 56), and 3 cytologically resynthesized ‘Young’ plants (2n = 49) as a basis for interpreting the postulated origin of ‘Young.’ Cytological evidence substantiated the conclusion that ‘Young’ is a hybrid between ‘Phenomenal’ and ‘Mayes.’ Contributions to the understanding of genomic relationships in Rubus are offered from detailed analyses of meiosis in ‘Phenomenal,’ ‘Mayes,’ ‘Young,’ and ‘Boysen.’ ‘Phenomenal’ and ‘Mayes’ both had a very regular meiosis. ‘Young,’ as well as ‘Boysen,’ showed a greater degree of chromosome association than either parent of ‘Young.’ Meiotic behavior in ‘Boysen’ presented a close parallel to that of ‘Young’ which, correlated with morphological similarities and the same 2n chromosome number, suggests a similar origin. The mode of reproduction in ‘Young’ and ‘Boysen’ was found to be sexual on the basis of morphological variation in the open-pollinated (selfed) progeny, the varying aneuploid somatic chromosome numbers in these progeny (2n = 32–54) and aneuploid chromosome numbers in hybrids having either variety as one parent. The productiveness of ‘Young’ and ‘Boysen’ in commercial plantings and their successful utilization in breeding programs indicate a high fertility regardless of their having an odd multiple of the basic number. It is concluded that the production of balanced euploid gametes is not necessarily a criterion of fertility, at least not at this high level of ploidy.  相似文献   

9.
Siniša Urban 《The EMBO journal》2014,33(24):2883-2884
The reclusive enzymes that catalyze proteolysis inside the cell membrane are among the most widespread in nature, yet most remain ‘orphans’ whose cellular functions are poorly understood. Now, Voss et al identify Golgi‐resident glycosyltransferases and glycosidases as substrates for the presenilin‐like protease SPPL3. Shedding of these glycan‐modifying enzymes from the membrane down‐regulates global protein N‐glycosylation.  相似文献   

10.
《农业工程》2021,41(4):259-284
Diversity, stand structure and regeneration potential are the key elements of any forest ecosystem. For the present study, seven sites were selected with the aims of assessing plant diversity, structure and regeneration potential in tropical forests across Kanyakumari Wildlife Sanctuary (KWLS), Western Ghats, India. The sites were classified based on the similarity: tropical dry deciduous sites (TDDs I and II), tropical semi-evergreen sites (TSEs I and II) and tropical evergreen sites (TEFs I-III). The phytosociological survey was done by laying a total of 70 plots (10 plots in each study site). Standard methods were followed for the assessment of diversity, structure and regeneration patterns. A total of 267 species (205 genera, 70 families) were recorded. The tree species richness ranged 24 (TDD II) – 76 (TEF III). Of the vegetation spectrum, trees, vines and understorey accounted 56.5, 15.3 and 28.2% respectively to the total flora documented. A total of 66 species were endemic. The total tree density and tree basal area (seedlings, saplings, juveniles and adults) were 18,790 individuals (mean 2684) and 137.6 m2 (mean 19.7 m2) in 70 plots respectively. The mean tree adult density and basal area ranged 370 (TDD I) – 900 (TEF I) individuals/ha and 24.2 (TDD I) – 75.3 (TEF III) m2/ha respectively. The overall species richness was highest in TDD I, but TEF III had the highest tree species richness. The diameter class-wise distribution showed the characteristic ‘reverse J-shaped’ curve. Most tree species were ‘newly recruited’. The dominant species had ‘fair’ to ‘good’ regeneration potential. However, 12 tree species showed ‘no’ regeneration. The overall regeneration pattern of trees was ‘good’, but ‘no’ or ‘poor’ regeneration patterns in some tree species, especially endemics is a point of concern. Since a majority of tree species were ‘new recruits’, species composition may likely change in the future. The results obtained would help in understanding diversity patterns, structural attributes and regeneration potential in tropical forests of protected areas for better forest management and conservation.  相似文献   

11.
This study reports cases in which grandmothers and other closely related adult females cared for orphans in the Arashiyama E-troop, a provisioned troop of Japanese macaques (Macaca fuscata). I observed the behavioral patterns of three orphans (aged 1, 2, and 3 years, respectively). The grandmothers cared for two orphans, while three other closely related adult females cared for the rest of the orphans whose grandmothers were absent. These observations differ from those of previous studies that reported that grandmothers were indifferent towards orphans. This intraspecific variation may be attributed to the demographic conditions of the troop in this study, which had only a few related nulliparous adult females, as a result of artificial birth control. In this group, adult females showed decreased fecundity and an increased interbirth interval as they received birth control treatment; thus, in the absence of their own dependent infants, these females may have invested time in the care of related orphans. Although caregiving by grandmothers is believed to be rare or insignificant in primates, this study suggests that grandmothers and other closely related adult females play an important role for orphans in troops with few related adult females.  相似文献   

12.
以厦门地区夏季播种的抗热松花型台湾花椰菜Brassica oleracea var. botrytis品种为材料,比较各品种生物学性状、营养成分、矿质元素、能源、植物功能性指标,并以低能高营养的消费原则,采用平均隶属函数值对品种进行评价。结果表明,平均隶属函数值依次为‘雪松’(4.805) >‘香雪’(3.282) >‘雪丽’(2.279) >‘庆农S90’(1.037)。结合生育期考虑,‘雪松’为夏季较适合在厦门地区推广的松花型花椰菜抗热新品种。  相似文献   

13.
《Animal behaviour》1988,36(4):1025-1037
In many species of cercopithecines a female inherits her mother's (or genealogical) rank. Matrilineal rank inheritance may be defined in general terms as the process whereby a female (termed ‘dependent’) acquires the rank of an ‘ally’ above another female (‘target’). An attempt was made to reproduce this process in time-lapse form in a group of 17 Japanese macaques, Macaca fuscata, comprised of three families with similar age-sex compositions. Experimental female subgroups were formed such that in each of them a female (dependent) was given more alliance power than a dominant target. The results indicate that in each of the subgroups that was tested the dependent female inherited the rank of her ally (mother or older sister) above same-age or older targets. Four processes of rank inheritance were observed. The fact that females who were given more alliance power did not solicit their ally, or challenge the target females, before they were aided by their ally suggests that aggressive interventions are the primary mechanism of rank inheritance. The results also account for the reported rarity of aggressive interventions in natural groups and for the observation that orphans may nevertheless inherit the rank of their family. The role and dynamics of the recognition of alliances in the establishment of rank relationships are discussed.  相似文献   

14.
In the United States, low-income or minority populations tend toward earlier births than the more advantaged. In disadvantaged populations, one factor that may exert pressure toward early births is “weathering,” or pervasive health uncertainty. Are subjective perceptions of health related to fertility timing? Drawing on a small sample of intensive interviews with teenage mothers-to-be, I suggest that low-income African American teenagers may expect uncertain health and short lifespans. Where family economies and caretaking systems are based on kin networks, such perceptions may influence the decision to become a young mother. Heuristic typologies of ways socially situated knowledge may contribute to the reproduction of fertility timing practices contrast the experiences of poor African American interviewees, working class white interviewees, and middle-class teens who typically postpone childbearing.  相似文献   

15.
This paper is a critique of ‘integrative medicine’ as an ideal of medical progress on the grounds that it fails to realise the cognitive value of alternative medicine. After a brief account of the cognitive value of alternative medicine, I outline the form of ‘integrative medicine’ defended by the late Stephen Straus, former director of the US National Centre for Complementary and Alternative Medicine. Straus’ account is then considered in the light of Zuzana Parusnikova’s recent criticism of ‘integrative medicine’ and her distinction between ‘cognitive’ and ‘opportunistic’ engagement with alternative medicine. Parusnikova warns that the medical establishment is guilty of ‘dogmatism’ and proposes that one can usefully invoke Karl Popper’s ‘critical rationalism’ as an antidote. Using the example of Straus, I argue that an appeal to Popper is insufficient, on the grounds that ‘integrative medicine’ can class as a form of cognitively-productive, critical engagement. I suggest that Parusnikova’s appeal to Popper should be augmented with Paul Feyerabend’s emphasis upon the role of ‘radical alternatives’ in maximising criticism. ‘Integrative medicine’ fails to maximise criticism because it ‘translates’ alternative medicine into the theories and terminology of allopathic medicine and so erodes its capacity to provide cognitively-valuable ‘radical alternatives’. These claims are then illustrated with a discussion of ‘traditional’ and ‘medical’ acupuncture. I conclude that ‘integrative medicine’ fails to exploit the cognitive value of alternative medicine and so should be rejected as an ideal of medical progress.  相似文献   

16.
Horticulture – like many other traditional crafts in Britain – is said to suffer from a ‘skills problem’. A recent survey suggests that one of the reasons for this is increased outsourcing of horticultural work from public employers to private contractors. While anthropologists have generally acknowledged the politics of learning, they have had little to say about enskillment in work contexts which have been reconfigured in a way that leaves hardly any room for institutionalized methods of learning. Private gardening contractors are an example of such a work context, and in this article I scrutinize their practices to show the various ways in which enskillment is inhibited. Rather than referring to the concept of ‘deskilling’ – usually evoked in discussions of skills problems – I employ the notion of an inhibition of enskillment in order to emphasize that every feature that fosters skill also has a ‘shadow side’ to it which bears a potential to inhibit skill. Implicit in this argument is a critique of neoliberal work practices which shape enskillment as well as the natural environment.  相似文献   

17.
Conventional, vertex-ipsilateral ear records (‘A’), as well as 3-channel Lissajous' trajectories (3-CLTs) of auditory brain-stem evoked potentials (ABEPs) were recorded from the scalp simultaneously with tympanic membrane electrocochleograms (‘TME’) and auditory nerve compound action potentials (‘8-AP’) recorded intracranially using a wick electrode on the auditory nerve between the internal auditory meatus and the brain-stem. The recordings were made during surgical procedures exposing the auditory nerve.The peak latency recorded from ‘TME’ corresponded to trajectory amplitude peak ‘a’ of 3-LLT and to peak ‘I’ of the ‘A’ channel ABEP. Peak latency of ‘8-AP’ was slightly longer than the latency of peak ‘II’ of ‘A’ when ‘8-AP’ was recorded from the root entry zone and the same or shorter when recorded from the nerve trunk. ‘8-AP’ peak latency was shorter than trajectory amplitude peak ‘b’ of 3-CLT regardless of where the wick electrode was along the nerve. Peak latencies from all recordings sites clustered into two distinct groups—those that included N1 from ‘TME’, peak ‘I’ of the ‘A’ record and trajectory amplitude peak ‘a’ of 3-CLT, and those that included the negative peak of ‘8-AP’ and trajectory amplitude peak ‘b’ of 3-CLT, as well as peak ‘II’ of the ‘A’ record, when present. In one case, the latency of peak ‘II’ and trajectory amplitude peak ‘b’ was manipulated by changing the conductive properties of the medium surrounding the auditory nerve.These results are consistent with other evidence proposing: (1) the most distal (cochlear) portion of the auditory nerve is the generator of the first ABEP component (‘I’, ‘a’); (2) the proximal auditory nerve is the major contributor to the ‘A’ channel ABEP component ‘II’; (3) in addition to the auditory nerve, more central structures participate in the generation of the 3-CLT ‘b’ component.  相似文献   

18.
Do trees of life have roots? What do these roots look like? In this contribution, I argue that research on the origins of life might offer glimpses on the topology of these very roots. More specifically, I argue (1) that the roots of the tree of life go well below the level of the commonly mentioned ‘ancestral organisms’ down into the level of much simpler, minimally living entities that might be referred to as ‘protoliving systems’, and (2) that further below, a system of roots gradually dissolves into non-living matter along several functional dimensions. In between non-living and living matter, one finds physico-chemical systems that I propose to characterize by a ‘lifeness signature’. In turn, this ‘lifeness signature’ might also account for a diverse range of biochemical entities that are found to be ‘less-than-living’ yet ‘more-than-non-living’.  相似文献   

19.
Despite the amount of work that has been produced on the subject over the years, the ‘transformation of cladistics’ is still a misunderstood episode in the history of comparative biology. Here, I analyze two outstanding, highly contrasting historiographic accounts on the matter, under the perspective of an influential dichotomy in the philosophy of science: the opposition between Scientific Realism and Empiricism. Placing special emphasis on the notion of ‘causal grounding’ of morphological characters (sensu Olivier Rieppel) in modern developmental biology’s (mechanistic) theories, I arrive at the conclusion that a ‘new transformation of cladistics’ is philosophically plausible. This ‘reformed’ understanding of ‘pattern cladistics’ entails retaining the interpretation of cladograms as ‘schemes of synapomorphies’, but in association to construing cladogram nodes as ‘developmental-genetic taxic homologies’, instead of ‘standard Darwinian ancestors’. The reinterpretation of pattern cladistics presented here additionally proposes to take Bas Van Fraassen’s ‘constructive empiricism’ as a philosophical stance that could properly support such analysis of developmental-genetic data for systematic purposes. The latter suggestion is justified through a reappraisal of previous ideas developed by prominent pattern cladists (mainly, Colin Patterson), which concerned a scientifically efficient ‘observable/non-observable distinction’ linked to the conceptual pair ‘ontogeny and phylogeny’. Finally, I argue that a robust articulation of Antirealist alternatives in systematics may provide a rational basis for its disciplinary separation from evolutionary biology, as well as for a critical reconsideration of the proper role of certain Scientific Realist positions, currently popular in comparative biology.  相似文献   

20.
Accurate and large‐scale prediction of protein–protein interactions directly from amino‐acid sequences is one of the great challenges in computational biology. Here we present a new Bayesian network method that predicts interaction partners using only multiple alignments of amino‐acid sequences of interacting protein domains, without tunable parameters, and without the need for any training examples. We first apply the method to bacterial two‐component systems and comprehensively reconstruct two‐component signaling networks across all sequenced bacteria. Comparisons of our predictions with known interactions show that our method infers interaction partners genome‐wide with high accuracy. To demonstrate the general applicability of our method we show that it also accurately predicts interaction partners in a recent dataset of polyketide synthases. Analysis of the predicted genome‐wide two‐component signaling networks shows that cognates (interacting kinase/regulator pairs, which lie adjacent on the genome) and orphans (which lie isolated) form two relatively independent components of the signaling network in each genome. In addition, while most genes are predicted to have only a small number of interaction partners, we find that 10% of orphans form a separate class of ‘hub’ nodes that distribute and integrate signals to and from up to tens of different interaction partners.  相似文献   

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