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51.
Priscila A. Grohmann Ricardo S. Absalão Vera Maria Abud P. da Silva 《Journal of Natural History》2013,47(25-28):1865-1874
Project HABITATS was recently initiated in the Campos Basin (20.5–24° S), state of Rio de Janeiro, to assess biological impacts of petroleum exploration and exploitation on the continental shelf and slope of Brazil. Among species discovered in benthic samples from the area is the hydroid Monobrachium parasitum Mereschkowsky, 1877, occurring in an epibiotic association with the pelecypod mollusc Mendicula ferruginosa (Forbes, 1844): this is the first report of an association between the two species. Monobrachium parasitum has always been reported from cold waters, and is generally considered bipolar. This report records the occurrence of M. parasitum at lower latitudes, where they have seldom been collected: it is also the first account of this species from South America and the southwestern Atlantic. Moreover, the bathymetric distribution of M. parasitum is extended to a depth of 998 m. No previous records exist of hydroids from the Brazilian continental slope. 相似文献
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Berenice Martínez‐Rivera Daniel Ventosa‐Santaulària J. Eduardo Vera‐Valdés 《Journal of forecasting》2012,31(3):245-259
P. C. B. Phillips (1998) demonstrated that deterministic trends are a valid representation of an otherwise stochastic trending mechanism; he remained skeptic, however, about the predictive power of such representations. In this paper we prove that forecasts built upon spurious regression may perform (asymptotically) as well as those issued from a correctly specified regression. We derive the order in probability of several in‐sample and out‐of‐sample predictability criteria ( test, root mean square error, Theil's U‐statistics and R2) using forecasts based upon a least squares‐estimated regression between independent variables generated by a variety of empirically relevant data‐generating processes. It is demonstrated that, when the variables are mean stationary or trend stationary, the order in probability of these criteria is the same whether the regression is spurious or not. Simulation experiments confirm our asymptotic results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
53.
Chan VS Chan KY Chen Y Poon LL Cheung AN Zheng B Chan KH Mak W Ngan HY Xu X Screaton G Tam PK Austyn JM Chan LC Yip SP Peiris M Khoo US Lin CL 《Nature genetics》2006,38(1):38-46
Severe acute respiratory syndrome (SARS) is caused by infection of a previously undescribed coronavirus (CoV). L-SIGN, encoded by CLEC4M (also known as CD209L), is a SARS-CoV binding receptor that has polymorphism in its extracellular neck region encoded by the tandem repeat domain in exon 4. Our genetic risk association study shows that individuals homozygous for CLEC4M tandem repeats are less susceptible to SARS infection. L-SIGN is expressed in both non-SARS and SARS-CoV-infected lung. Compared with cells heterozygous for L-SIGN, cells homozygous for L-SIGN show higher binding capacity for SARS-CoV, higher proteasome-dependent viral degradation and a lower capacity for trans infection. Thus, homozygosity for L-SIGN plays a protective role during SARS infection. 相似文献
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The Soviet All-Union Society of Neurologists and Psychiatrists has resigned from the World Psychiatric Association (WPA). The resignation was not unexpected in the face of a growing move by Western psychiatric associations to expel the Soviet society because of its refusal to cooperate with the WPA's committee to monitor political misuse of psychiatry. 相似文献
56.
The World Psychiatric Association has been asked to intervene on behalf of four Polish internees who are claiming to be victims of psychiatric repression for political reasons. Under martial law, Poland's security forces have shown a renewed interest in psychiatric internment of disruptive persons. 相似文献
57.
Summary Proteins were exposed to acetaldehyde vapour or mixed with glucose in solution and the basic groups determined by their dy binding capacity. Only serum albumin shows a marked decrease of basic groups and of the carbon/nitrogen ratio as a sign of condensation of aldehyde and amine groups. These results were corroborated by the direct estimation of the aldehyde resine formed on the protein: serum albumin and fibrin treated with acetaldehyde vapour contained 5 to 10 times more resin than the other proteins examined. No rapid combination between serum proteins and glucose could be demonstrated by the dy method or by the kinetics of change of pH. The slow reaction seems not to be dependent on denaturation. 相似文献
58.
Zenker M Mayerle J Lerch MM Tagariello A Zerres K Durie PR Beier M Hülskamp G Guzman C Rehder H Beemer FA Hamel B Vanlieferinghen P Gershoni-Baruch R Vieira MW Dumic M Auslender R Gil-da-Silva-Lopes VL Steinlicht S Rauh M Shalev SA Thiel C Ekici AB Winterpacht A Kwon YT Varshavsky A Reis A 《Nature genetics》2005,37(12):1345-1350
Johanson-Blizzard syndrome (OMIM 243800) is an autosomal recessive disorder that includes congenital exocrine pancreatic insufficiency, multiple malformations such as nasal wing aplasia, and frequent mental retardation. We mapped the disease-associated locus to chromosome 15q14-21.1 and identified mutations, mostly truncating ones, in the gene UBR1 in 12 unrelated families with Johanson-Blizzard syndrome. UBR1 encodes one of at least four functionally overlapping E3 ubiquitin ligases of the N-end rule pathway, a conserved proteolytic system whose substrates include proteins with destabilizing N-terminal residues. Pancreas of individuals with Johanson-Blizzard syndrome did not express UBR1 and had intrauterine-onset destructive pancreatitis. In addition, we found that Ubr1(-/-) mice, whose previously reported phenotypes include reduced weight and behavioral abnormalities, had an exocrine pancreatic insufficiency, with impaired stimulus-secretion coupling and increased susceptibility to pancreatic injury. Our findings indicate that deficiency of UBR1 perturbs the pancreas' acinar cells and other organs, presumably owing to metabolic stabilization of specific substrates of the N-end rule pathway. 相似文献
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Chini R Hoffmeister V Kimeswenger S Nielbock M Nürnberger D Schmidtobreick L Sterzik M 《Nature》2004,429(6988):155-157
The formation of low-mass stars like our Sun can be explained by the gravitational collapse of a molecular cloud fragment into a protostellar core and the subsequent accretion of gas and dust from the surrounding interstellar medium. Theoretical considerations suggest that the radiation pressure from the protostar on the in-falling material may prevent the formation of stars above ten solar masses through this mechanism, although some calculations have claimed that stars up to 40 solar masses can in principle be formed via accretion through a disk. Given this uncertainty and the fact that most massive stars are born in dense clusters, it was suggested that high-mass stars are the result of the runaway merging of intermediate-mass stars. Here we report observations that clearly show a massive star being born from a large rotating accretion disk. The protostar has already assembled about 20 solar masses, and the accretion process is still going on. The gas reservoir of the circumstellar disk contains at least 100 solar masses of additional gas, providing sufficient fuel for substantial further growth of the forming star. 相似文献