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1.
Abstract

Border policing and immigration law enforcement produce a spectacle that enacts a scene of ‘exclusion’. Such spectacles render migrant ‘illegality’ visible. Thus, these material practices help to generate a constellation of images and discursive formations, which repetitively supply migrant ‘illegality’ with the semblance of an objective fact. Yet, the more these spectacles fuel anti-immigrant controversy, the more the veritable inclusion of the migrants targeted for exclusion proceeds apace. Their ‘inclusion’ is finally devoted to the subordination of their labour, which is best accomplished only insofar as their incorporation is persistently beleaguered with exclusionary campaigns that ensure that this inclusion is itself a form of subjugation. At stake, then, is a larger sociopolitical (and legal) process of inclusion through exclusion. This we may comprehend as the obscene of inclusion. The castigation of ‘illegals’ thereby supplies the rationale for essentializing citizenship inequalities as categorical differences that then may be racialized.  相似文献   

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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   

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This synopsis of the species of the genus Henneguya (Myxozoa, Myxosporea, Myxobolidae) includes a total of 146 species. Morphometric and morphological (when available) features are indicated for each species. Data related to the hosts are also provided.  相似文献   

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In the years following World War II, and increasingly during the 1960s and 1970s, professional scientific societies developed internal sub-committees to address the social implications of their scientific expertise (Moore, Disrupting Science: Social Movements, American Scientists, and the Politics of the Military, 19451975. Princeton: Princeton University Press, 2008). This article explores the early years of one such committee, the American Society of Human Genetics’ “Social Issues Committee,” founded in 1967. Although the committee’s name might suggest it was founded to increase the ASHG’s public and policy engagement, exploration of the committee’s early years reveals a more complicated reality. Affronted by legislators’ recent unwillingness to seek the expert advice of human geneticists before adopting widespread neonatal screening programs for phenylketonuria (PKU), and feeling pressed to establish their relevance in an increasingly resource-scarce funding environment, committee members sought to increase the discipline’s expert authority. Painfully aware of controversy over abortion rights and haunted by the taint of the discipline’s eugenic past, however, the committee proceeded with great caution. Seeking to harness interest in and assert professional control over emerging techniques of genetic diagnosis, the committee strove to protect the society’s image by relegating ethical and policy questions about their use to the individual consciences of member scientists. It was not until 1973, after the committee’s modest success in organizing support for a retrospective public health study of PKU screening and following the legalization of abortion on demand, that the committee decided to take a more publicly engaged stance.  相似文献   

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Vadell EM  Cavender JC 《Mycologia》2007,99(1):112-124
Thirteen new species and varieties of dictyostelid cellular slime molds (csm) were isolated from soils of the Atlantic Subtropical Rain Forest at the Iguazú Falls, Northeastern Misiones Province, Argentina. Seven new species are described herein, one of them is a Polysphondylium, while the rest of the species belong to the genus Dictyostelium. Also, six taxa are new varieties of Dictyostelium and Acytostelium, which will be reported later. Fourteen Northern Hemisphere (Tikal) species have also been isolated from Iguazú soils, some of them new records for Southern South America. This csm community, when compared with others from forests of the Northern Hemisphere, particularly Tikal, Guatemala, give some insight into a possibly different evolutionary history and/or natural selection in the two areas.  相似文献   

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Different constructions of the fetus lie at the centre of reproductive, abortion and disability politics. Recent developments mean that, within the same hospital, a fetus may be perceived in contrasting and potentially conflicting ways. It is also argued that the status given to the fetus is directly relevant to the status given to pregnant women. During group discussions facilitated by an ethicist, health-care staff highlighted various perceptions of the fetus which included: person; patient; 'nobody'; commodity. Perhaps not surprisingly in view of the current legal situation, staff tended to claim that it is usually the pregnant women who decides how her fetus will be constructed, and the practitioner who responds to this. However, various ways in which practitioners might influence women's perceptions of their fetus are highlighted, as are some ways in which the perceptions of staff might be influenced. This paper illustrates how sensitive health-care staff will need to be if they are indeed to respond to, rather than shape, women's constructions of their fetus.  相似文献   

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This paper analyses acarological evidence from a 130-year-old forensic investigation. It was the first case in forensic acarology, i.e., the first case where mites provided substantial information to estimate the post-mortem interval (PMI). In 1878, the mites found in the mummified body of a newborn baby girl in Paris, France, were studied by acarologist and forensic entomologist Jean Pierre Mégnin. Mégnin estimated around 2.4 million mites in the skull and identified them as Tyroglyphus longior (Gervais), a junior synonym of Tyrophagus longior. He suggested that the arrival of these mites at the corpse would have occurred by phoresy on carrier insects, roughly 5 months before the autopsy. There is no doubt about the identification of the mites, Mégnin was a highly respected acarologist. However, two main factors affecting the biology of Tyrophagus mites were not included in the original analysis. First, Mégnin stated that the mites were phoretic. However, he probably did not have access to information about the natural history of the species, because as a rule Tyrophagus mites are non-phoretic. Considering the omnipresence of Tyrophagus mites in soil, most likely the mites will have arrived almost immediately after death. Second, temperature was not taken into account during the estimations of the mite population growth rate. The new analysis is based on current knowledge of Tyrophagus biology and includes temperature, estimated following a handful of weather reports of the years 1877 and 1878. The new projections indicate that non-phoretic mites may have colonised the body just after death and the colony would have built up over 8 months, contrary to the 5 months proposed by Mégnin. This new lapse of time agrees with the PMI proposed by Brouardel: on 15 January 1878 he postulated the death of the newborn to have occurred some 8 months before the autopsy.  相似文献   

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Homeostasis is a basic concept in investigating all living systems. Homeostasis and life are synonyms to a certain extent. The concept of homeostasis has been studied and developed for more than 150 years; however, only the 21st century brought us close to understanding homeostasis as a state of a biosystem and a continuous process. The chaos and self-organization theory (CSOT) proves that the conventional views based on determinism (functional analysis) or stochastics (when stochastic uncertainty or certainty occurs) cannot describe homeostasis as defined by W.B. Cannon and his followers. The new CSOT shows a clear boundary between determinism, stochastics (and deterministic chaos), and third-type systems, which have five special properties (principles of self-organization) and can be described in terms of quasiattractors. Kinematics is understood as the motion of quasi-attractors in the phase spaces of states. Complexity is introduced as the rate of evolution of complex biological systems, differing from the definition by Prigogine–Glansdorff. At the same time, concepts of uncertainty of the first and second types and an analog of the Heisenberg calculus are introduced for complexity. According to these concepts, complex biosystems are transferred from the area of traditional science to a new area of the theory of chaos and self-organization.  相似文献   

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The Omicron variant rapidly became the dominant SARS-CoV-2 strain in South Africa and elsewhere. This review explores whether this rise was due to an increased transmission of the variant or its escape from population immunity by an extensively mutated spike protein. The mutations affected the structure of the spike protein leading to the loss of neutralization by most, but not all, therapeutic monoclonal antibodies. Omicron also shows substantial immune escape from serum antibodies in convalescent patients and vaccinees. A booster immunization increased, however, the titre and breadth of antiviral antibody response. The cellular immune response against Omicron was largely preserved explaining a satisfying protection of boosted vaccinees against severe infections. Clinicians observed less severe infection with Omicron, but other scientists warned that this must not necessarily reflect less intrinsic virulence. However, in animal experiments with mice and hamsters, Omicron infections also displayed a lesser virulence than previous VOCs and lung functions were less compromised. Cell biologists demonstrated that Omicron differs from Delta by preferring the endocytic pathway for cell entry over fusion with the plasma membrane which might explain Omicron’s distinct replication along the respiratory tract compared with Delta. Omicron represents a distinct evolutionary lineage that deviated from the mainstream of evolving SARS-CoV-2 already in mid-2020 raising questions about where it circulated before getting widespread in December 2021. The role of Omicron for the future trajectory of the COVID-19 pandemic is discussed.  相似文献   

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Uranium is a natural radioactive metallic element; its effect on the organism is cumulative, and chronic exposure to this element can induce carcinogenesis. Three cities of the Amazon region—Monte Alegre, Prainha, and Alenquer—in North Brazil, are located in one of the largest uranium mineralization areas of the world. Radon is a radioactive gas, part of uranium decay series and readily diffuses through rock. In Monte Alegre, most of the houses are built of rocks removed from the Earth’s crust in the forest, where the uranium reserves lie. The objective of the present work is to determine the presence or absence of genotoxicity and risk of carcinogenesis induced by natural exposure to uranium and radon in the populations of these three cities. The frequency of micronuclei (MN) and chromosomal aberrations (CA) showed no statistically significant differences between the control population and the three study populations (P > 0.05). MN was also analyzed using the fluorescence in situ hybridization (FISH) technique, with a centromere-specific probe. No clastogenic and/or aneugenic effects were found in the populations. Using FISH analysis, other carcinogenesis biomarkers were analyzed, but neither the presence of the IGH/BCL2 translocation nor an amplification of the MYC gene and 22q21 region was detected. Clastogenicity and DNA damage were also not found in the populations analyzed using the alkaline comet assay. The mitotic index showed no cytotoxicity in the analyzed individuals’ lymphocytes. Once we do not have data concerning radiation doses from other sources, such as cosmic rays, potassium, thorium, or anthropogenic sources, it is hard to determine if uranium emissions in this geographic region where our study population lives are too low to cause significant DNA damage. Regardless, genetic analyses suggest that the radiation in our study area is not high enough to induce DNA alterations or to interfere with mitotic apparatus formation. It is also possible that damages caused by radiation doses undergo cellular repair.  相似文献   

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In two landmark articles, Hanahan and Weinberg synthesized into one conceptual framework 'the hallmarks of cancer', a massive amount of information describing the characteristics of a cancer cell. Although this is neither the intention nor the belief of the authors, hallmarks are often interpreted as applying to a canonic cancer cell, or equally to all cells within a cancer. In this article, we clarify the separate concepts of causes, oncogenic events, signal transduction programs, and hallmarks to show that there is no unimodal relation between these concepts but a complex network of interrelations that vary in different cells, between cells, and at different times in any given cell. We consider cancer as an evolving, dynamic, and heterogeneous system, explaining, at least in part, the difficulty of treating cancer and supporting the use of simultaneous, multitarget therapies.  相似文献   

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It is fairly well known that Darwin was inspired to formulate his theory of natural selection by reading Thomas Malthus’s Essay on the Principle of Population. In fact, by reading Darwin’s notebooks, we can even locate one particular sentence which started Darwin thinking about population and selection. What has not been done before is to explain exactly where this sentence – essentially Malthus’s ideas about geometric population growth – came from. In this essay we show that eighteenth century mathematician Leonhard Euler is responsible for this sentence, and in fact forms the beginning of the logical chain which leads to the creation of the theory of natural selection. We shall examine the fascinating path taken by a mathematical calculation, the many different lenses through which it was viewed, and the path through which it eventually influenced Darwin.  相似文献   

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Central nervous system (CNS) development involves neural patterning, neuronal and axonal migrations, and synapse formation. DSCAM, a chromosome 21 axon guidance molecule, is expressed by CNS neurons during development and throughout adult life. We now report that DSCAM and its chromosome 11 paralog DSCAML1 exhibit inverse ventral-dorsal expression patterns in the developing spinal cord and distinct, partly inverse, expression patterns in the developing cortex, beginning in the Cajal-Retzius cells. In the adult cortex, DSCAM predominates in layer 3/5 pyramidal cells and DSCAML1 predominates in layer 2 granule cells. In the cerebellum, DSCAM is stronger in the Purkinje cells and DSCAML1 in the granule cells. Finally, we find that the predicted DSCAML1 protein contains 60 additional N-terminal amino acids which may contribute to its distinct expression pattern and putative function. We propose that the DSCAMs comprise novel elements of the pathways mediating dorsal-ventral patterning and cell-fate specification in the developing CNS.  相似文献   

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Phycobilisome (PBS) complexes are massive light-harvesting apparati in cyanobacteria that capture and funnel light energy to the photosystem. PBS complexes are dynamically degraded during nutrient deprivation, which causes severe chlorosis, and resynthesized during nutrient repletion. PBS degradation occurs rapidly after nutrient step down, and is specifically triggered by non-bleaching protein A (NblA), a small proteolysis adaptor that facilitates interactions between a Clp chaperone and phycobiliproteins. Little is known about the mode of action of NblA during PBS degradation. In this study, we used chemical cross-linking coupled with LC-MS/MS to investigate the interactions between NblA and phycobiliproteins. An isotopically coded BS3 cross-linker captured a protein interaction between NblA and β-phycocyanin (PC). LC-MS/MS analysis identified the amino acid residues participating in the binding reaction, and demonstrated that K52 in NblA is cross-linked to T2 in β-PC. These results were modeled onto the existing crystal structures of NblA and PC by protein docking simulations. Our data indicate that the C-terminus of NblA fits in an open groove of β-PC, a region located inside the central hollow cavity of a PC rod. NblA may mediate PBS degradation by disrupting the structural integrity of the PC rod from within the rod. In addition, M1-K44 and M1-K52 cross-links between the N-terminus of NblA and the C-terminus of NblA are consistent with the NblA crystal structure, confirming that the purified NblA is structurally and biologically relevant. These findings provide direct evidence that NblA physically interacts with β-PC.  相似文献   

20.
Seasonal variation in the occurrence of cardiovascular and cerebrovascular events, including pulmonary embolism (PE), has been reported; however, recent large‐scale, population‐based studies conducted in the United States did not confirm such seasonality. The aim of this large‐scale population study was to determine whether a temporal pattern in the occurrence of PE exists. The analysis considered all consecutive cases of PE in the database of all hospital admissions of the Emilia Romagna region in Italy at the Center for Health Statistics between January 1998 and December 2005. PE cases were first grouped according to season of occurrence, and the data were analyzed by the χ2 test for goodness of fit. Then, inferential chronobiologic (cosinor and partial Fourier) analysis was applied to monthly data, and the best‐fitting curve for the annual variation was derived. The total sample consisted of 19,245 patients (8,143 male, mean age 71.6±14.1 yrs; 11,102 female, mean age 76.1±13.7 yrs). Of these, 2,484 were <65 yrs, 5,443 were between 65 and 74, and 11,318 were ≥75 yrs. There were 4,486 (23.3%) fatal‐case outcomes. PE occurred least frequently in spring (n=4,442 or 23.1%) and most frequent in winter (n=5,236 or 27.2%, goodness of fit χ2=75.75, p<0.001). Similar results were obtained for subgroups formed by gender, age, fatal/non‐fatal outcome, presence/absence of major underlying co‐morbid conditions, and specific risk factors. Inferential chronobiological analysis identified a significant annual pattern in PE, with the peak between November and December for the total sample of cases (p<0.001), males (p<0.001), females (p=0.002), fatal and non‐fatal cases (p<0.001 for both), and subgroups formed by age (<65 yrs, p=0.012; 65–74 yrs, p<0.001; ≥75 yrs, p=0.012). This pattern was independent of the presence/absence of hypertension (p=0.003 and p<0.001, respectively), pulmonary disease (p<0.001 and p<0.001, respectively), stroke (p<0.001 and p=0.004, respectively), neoplasms (p=0.005 and p=0.001, respectively), heart failure (p=0.022 and p<0.001, respectively), and deep vein thrombosis (p=0.002 and p<0.001, respectively). However, only a non‐statistically significant trend was found for subgroups formed by cases of diabetes mellitus, infections, renal failure, and trauma.  相似文献   

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