首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
In cells the quality of newly synthesized proteins is monitored in regard to proper folding and correct assembly in the early secretory pathway, the cytosol and the nucleoplasm. Proteins recognized as non-native in the ER will be removed and degraded by a process termed ERAD. ERAD of aberrant proteins is accompanied by various changes of cellular organelles and results in protein folding diseases. This review focuses on how the immunocytochemical labeling and electron microscopic analyses have helped to disclose the in situ subcellular distribution pattern of some of the key machinery proteins of the cellular protein quality control, the organelle changes due to the presence of misfolded proteins, and the efficiency of synthetic chaperones to rescue disease-causing trafficking defects of aberrant proteins.  相似文献   

3.
Situated at the intersection of anthropological work on illness narratives and research on the anthropology of autism, this paper is a close reading of an autobiographical narrative recounted by Peter, a young man diagnosed with Asperger’s Syndrome, a type of autism spectrum disorder (ASD). Responding to Solomon’s (2010a:252) call for phenomenologically grounded accounts of “the subjective, sensory, and perceptual experiences of autism … based on personal narratives and practices of being and self-awareness,” this paper calls into question key assumptions in the clinical and popular literature about ASD relating to theory of mind, empathy, capacity for metaphorical thinking, and ASD as a life-long condition.  相似文献   

4.
A comparative statistical study has been carried out on populations of modern algae, of Precambrian algal microfossils, of the organized elements of the Orgueil carbonaceous meteorite, and of the oldest microfossil-like objects now known (spheroidal bodies from the Fig Tree and Onverwacht Groups of the Swaziland Supergroup, South Africa). The distribution patterns exhibited by the >3000 m.y.-old Swaziland microstructures bear considerable resemblance to those of the abiotic organized elements but rather markedly differ from those exhibited by younger, assuredly biogenic, populations. Based on these comparisons it is concluded that the Swaziland spheroids could be, at least in part, of non-biologic origin; these oldest known fossil-like micro-structures should not be regarded as constituting firm evidence of Archean life.Given at the International Seminar Origin of Life, 2–7 August 1974, Moscow, U.S.S.R.  相似文献   

5.
The zooplankton composition is studied in the thermokarst, glacial and meteorite lakes, channels, former riverbeds, and hollows in the basin of Anadyr’. We found 174 taxa: 78, Rotatoria, 55, Cladocera, and 41, Copepoda. The most diverse is the lake fauna: 51 taxa of Rotatoria, 48, Cladocera, and 37, Copepoda. The thermokarst Lake Maiorskoe hosts 68 taxa: 31, Rotatoria, 14, Cladocera, and 23, Copepoda, wheras the cold ultraoligotrophic Lake El’gygytgyn features only one species of Cyclop of the group scutifer Cyclops neymanae Strel., and Rotatoria and Cladocera are present as allochtonous forms. The Copepoda illustrate the relations of the Anadyr’ fauna with those of Europe, North America, and Japan.  相似文献   

6.
7.
This article argues for a public sociology of ‘race’ that can respond to Weber's injunction that sociology should ‘meet the demands of the day’. While the author's version of these demands – for a society of autonomous individuals and groups, living as equals – is utopian, the main argument offered here is that a sociology of ‘race’ should be a modified version of Burawoy's ‘public sociology’. Adopting Bauman's notion of a sociology of interpreters, a further suggestion is that this type of sociology needs to be reflexive and affective. Based on an analysis of his own sociological education in the late 1960s, his participation in social and political movements in which ‘race’ was key, and with brief reference to the sociology of ‘race’, the author argues that the emotions that circulated in each arena need to be examined, acknowledged and incorporated if theoretical and practical progress is to be made.  相似文献   

8.
9.

Background

Although being a simple and effective index that has been widely used to evaluate academic output of scientists, the h-index suffers from drawbacks. One critical disadvantage is that only h-squared citations can be inferred from the h-index, which completely ignores excess and h-tail citations, leading to unfair and inaccurate evaluations in many cases.

Methodology /Principal Findings

To solve this problem, I propose the h’-index, in which h-squared, excess and h-tail citations are all considered. Based on the citation data of the 100 most prolific economists, comparing to h-index, the h’-index shows better correlation with indices of total-citation number and citations per publication, which, although relatively reliable and widely used, do not carry the information of the citation distribution. In contrast, the h’-index possesses the ability to discriminate the shapes of citation distributions, thus leading to more accurate evaluation.

Conclusions /Significance

The h’-index improves the h-index, as well as indices of total-citation number and citations per publication, by possessing the ability to discriminate shapes of citation distribution, thus making the h’-index a better single-number index for evaluating scientific output in a way that is fairer and more reasonable.  相似文献   

10.
Humans can distinguish between contours of similar orientation, and between directions of visual motion. There is consensus that both of these capabilities depend on selective activation of tuned neural channels. The bandwidths of these tuned channels are estimated here by modelling previously published empirical data. Human subjects were presented with a rapid stream of randomly oriented gratings, or randomly directed motions, and asked to respond when they saw a target stimulus. For the orientation task, subjects were less likely to respond when two preceding orientations were close to the target orientation but differed from each other, presumably due to a failure of summation. For the motion data, by contrast, subjects were more likely to respond when the vector sum of two previous directions was in the target direction. Fitting a cortical signal-processing model to these data showed that the direction bandwidth of motion sensors is about three times the bandwidth of orientation sensors, and that it is the large bandwidth that allows the summation of motion stimuli. The differing bandwidths of orientation and motion sensors presumably equip them for differing tasks, such as orientation discrimination and estimation of heading, respectively.  相似文献   

11.
Summary The funnel-canal organs on the dactyls of the shore crab, Carcinus maenas, are innervated by 3–24 sensory cells with unbranched dendrites, which attain a length of 500–1400 m. The outer dendritic segments are enclosed in a dendritic sheath and pass through the cuticle within a canal. Two dendrite types can be distinguished according to ultrastructural criteria: Type I has a long ciliary segment, A-tubules with an osmiophilic core and arms, and a thick ciliary rootlet. Type II possesses only a short ciliary segment and a thin ciliary rootlet. Each funnel-canal organ contains two type-I dendrites. Their ciliary bases appear a few m distal to those of the type-II dendrites (1 to 22 in number). Two inner and two to eight outer enveloping cells belong to a sensillum. The innermost enveloping cell contains a large scolopale. In the second enveloping cell single scolopale rods are present. Thus, the funnel-canal organs are characterized by structural features typical for mechano-sensitive scolopidia, on the one hand, and for chemoreceptors, on the other. Therefore, the funnel-canal organs are very likely bimodal sensilla (contact chemoreceptors). A comparison with other arthropod sensilla shows that cuticular mechanoreceptors of aquatic crustaceans generally exhibit a scolopidial organization.  相似文献   

12.
The article explores a popular volunteer movement in Thailand and its connection to Buddhist morality and contemporary Thai politics. The article argues that volunteering in Thailand is often conceived of as a gift in various ways: as a form of dana or selfless giving; a gift from ‘good people’ to those defined as ‘in need’ in society and a gift to the Thai nation as a whole. Indeed, when volunteering is said to be a gift to the Thai nation, it is not necessarily because of its ability to redistribute resources, but because of its perceived ability to cultivate moral values and ‘good people’ for the Thai nation. The paper explores the implications that stem from presenting volunteering as a gift, with a strong emphasis on morality and ‘good people’, and how this popular discourse on volunteering may contribute to the maintenance of political status quo in Thailand, particularly in the context of the ongoing political struggles in recent years.  相似文献   

13.
14.
Drowning unconformities and their related strata are important records of key tectonic and environmental events throughout Earth’s history. In the eastern Bird’s Head region of West Papua, Indonesia, Middle Miocene strata record a drowning unconformity present over much of western New Guinea, including several offshore basins. This study records platform carbonate strata overlain by mixed shallow- and deep-water units containing benthic and planktonic foraminiferal assemblages in several outcrop locations across the eastern Bird’s Head region. These heterolithic beds are interpreted as drowning successions that are terminated by a drowning unconformity. We define a succession exposed along the Anggrisi River in the eastern Bird’s Head as a stratotype for carbonate platform drowning in the Bird’s Head, analogous to similar faunal turnovers identified in its offshore basins. Detailed facies analyses, biostratigraphic dating, and paleoenvironmental interpretations using larger benthic and planktonic foraminifera collected from the Anggrisi River succession help to constrain the drowning event recorded onshore as beginning in the Burdigalian and ending in the Serravallian. The cause of platform drowning in the Bird’s Head is attributed to a reduction in the rates of carbonate accumulation due to the presence of excess nutrients in the depositional environment. Already foundering carbonate platforms due to environmental deterioration were left vulnerable to submergence and eventually succumbed to drowning. Low rates of carbonate production were outpaced by the rate of relative sea-level rise caused by high-amplitude oscillations in global glacio-eustatic sea-level change and/or regional tectonic subsidence. The duration of the drowning event across the entire Bird’s Head region is interpreted to have lasted a duration of approximately 9.5 My, between 18.0 and 8.58 Ma. This has implications when interpreting timings of sedimentary basin fill across western New Guinea and in other basins where carbonate platform drowning is recorded.  相似文献   

15.
16.
In different medical systems, notions of person, as patient and as healer, vary widely. An analysis of the talk of a practitioner of internal medicine in the U.S.A. reveals an understanding of patients as syndromes. The work of medicine is physiological integrity, distinct from personal and interpersonal integrity. It is suggested that the world view of this practitioner is consistent with the institutions of medicine in which he practices, and with historical movements in U.S. society and Western civilization more broadly.  相似文献   

17.
The ‘New Zealand flatworm’, Arthurdendyus triangulatus, is a native of the South Island of New Zealand, which has established in the UK, Ireland and the Faroe Islands. In its introduced range, it is a predator of lumbricid earthworms. To assess the impact of A. triangulatus on earthworm species, flatworm distributions were manipulated into ‘high’, control and ‘low’ densities within a replicated field experiment. Earthworm biomass in the ‘high’ flatworm density treatment was significantly lower than the control or ‘low’ treatments. This was due to a reduction in the anecic species Lumbricus terrestris and, to a lesser extent, Aporrectodea longa. There was little evidence of negative effects on other earthworm species, with even a weakly positive relationship between flatworm density and epigeic biomass. Principal components analysis showed a clear separation of anecic species from A. triangulatus, but the epigeic species Lumbricus festivus and Lumbricus rubellus grouped with A. triangulatus, suggesting that they could be benefitting from reduced intraguild competition. Flatworm densities of 0.8 per m2, comparable to natural infestations in grassland, were predicted to give a reduction in total earthworm biomass of c. 20 %. The bulk of this was comprised of a reduction in anecic species biomass. In particular, it is considered that A. triangulatus poses a serious risk to L. terrestris populations, with implications for soil functioning and indigenous earthworm-feeding wildlife.  相似文献   

18.
 In Craterostigmus tasmanianus, first results of the cellular organization of anal organs within the ’ano-genital’ capsule are presented. Each valve of the ’ano-genital’ capsule bears four pore fields ventrally, each of them consisting of several pore openings of the anal organs. The pores lead into a cuticle-lined pore channel, the base of which is surrounded by a single-layered epithelium that is composed of three different cell types. The main epithelium consists of radially arranged transport-active cells surrounded by exocrine cells, and the cells of the pore channel. The cells of the transporting epithelium show deep invaginations of the apical and basal cell surfaces and plasmalemma-mitochondrial complexes. These cells are covered by a specialized cuticle with a prominent subcuticle. Exocrine glands secrete a mucous layer on the cuticle of the main epithelium. The type of anal organ present in Craterostigmus tasmanianus shows similarities to coxal and anal organs found in other Pleurostigmophora in the chilopods. The possible function of the anal organs in uptaking water vapour is discussed. It is appropriate to call the organs within the ’ano-genital’ capsule of Craterostigmus tasmanianus ”anal organs”, as components of the genital segments are not involved. Accepted: 17 November 1996  相似文献   

19.
Focusing on ethnic Chinese as cultural citizens of the nation, this paper examines national identity in the context of generational change. In so doing, it connects to colonialist conceptions of identity the dominant framework of ethnicity that operates in Malaysia. It argues that this framework allows for the nationalist imagining of ‘Malaysian-Chinese’ as ‘outsiders’. In probing the complex conceptual relationship between ethnicity, national identity and cultural citizenship, this article asks: How does ‘ethnicity’ enter into negotiations over the ‘national’ in the cultural realm? What are the notions of cultural difference and national otherness that operate in the negative dualisms by which nation and ethnicity are defined? How are these dualisms tied to notions of authenticity and cultural citizenship? Using the novel The Harmony Silk Factory by Malaysian author Tash Aw to address these questions, this paper argues the need to rethink current policies and narratives of ethnic and national identity in Malaysia.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号