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71.
72.
Culture-dependent and -independent methods were used to investigate the small eukaryote composition of raw and finished waters in the Norwegian cities of Oslo, Tromsø, Fredrikstad and Oppegård. Probes with general applicability to the 18S rRNA genes of the small eukaryote consortium were used for PCR-denaturing gradient gel electrophoresis (DGGE), and in the generation of clone libraries using the TOPO™ cloning and sequencing system. The chosen probes invariably gave a single band in agarose gel electrophoresis, indicating amplification of an area of similar size. DGGE and cloning analyses resolved the bands into components representing many unique amplicons. Diversity and composition in the collection were studied by DNA-sequencing, and visual examination of DGGE patterns. The cloning approach enabled the putative identification of a total of approximately 100 unique small eukaryotes. The major fraction of these represented ciliated and flagellated protozoal species. This was in keeping with the findings from protozoal cultivation. DNA from a number of multicellular eukaryotes was also detected. Amoebal and fungal DNA was rarely found. The latter may indicate a low incidence or a bias in the analysis technique. The population of small eukaryotes appears typical for pristine waters and no primary pathogens were detected by culture-independent techniques. However, the potentially pathogenic protozoa Acanthamoeba castellanii was grown on one occasion from Oslo’s drinking water.DGGE allowed the identification of fewer amplicons (by excision and sequencing of bands) than by the cloning-transformation approach. The DGGE analysis revealed clear similarities between the compositions of the raw and treated waters, indicating that cells or DNA in the raw water pass through the treatment trains. Protozoal culture and heterotrophic plate count analysis consistently revealed viable cells in both raw and treated waters in Oslo. This indicates that a fraction of the clone library represents eukaryotic species surviving the treatment trains. The analyses here presented represent the first published study of the general small eukaryotic fraction of the Capital’s drinking water, and those of three other Norwegian cities. We suggest that DGGE profiles may have a value in judging physical treatment efficacy (removal of cells), but that direct cloning and sequencing studies is more amenable for characterization of uncultured microbes. 相似文献
73.
Barbara G. Delano Marianna S. Markell Frieda Wolf Ejiro Ugova Eli A. Friedman Moro O. Salifu 《Hemodialysis international. International Symposium on Home Hemodialysis》2002,6(1):54-57
There is limited use of home renal replacement therapies in the U.S.A. One percent of dialysis patients are on home hemodialysis (HHD) and only 9% undergo peritoneal dialysis (PD). In an effort to better understand this, 161 satellite hemodialysis patients in 6 units in Brooklyn were surveyed. Forty‐eight percent of patients were women, 86% were black, 5% white, 8% Hispanic, and 1% other. Mean age was 49.4 years (range 22 – 69 years). Etiology of renal disease was hypertension (41%), diabetes mellitus (31%), polycystic kidney disease (3%), systemic lupus erythematosus (4%), and other or unknown (21%). Patients were queried about knowledge of and attitudes toward home therapies. Seventy‐nine percent of patients knew of home dialysis. The source of this information was the nephrologist (59%), the social worker (14%), a nurse (8%), other patients (4%), and other sources (15%). Only 10% of patients had ever considered HHD. Fifty‐four percent were afraid to do self‐care at home and 35% were not interested. Surprisingly, only 3% felt they had no reliable helper and 8% felt that their housing was not suitable. Similarly, 78% of patients had been spoken to about PD, but only 11% had considered it. Forty‐one percent were afraid of doing self‐care on PD, and 45% were not interested. We conclude that, although the majority of patients in six inner‐city dialysis units had heard of home dialysis, only a small number ever considered it. As many patients were afraid of doing home therapy, better education about the risks and benefits needs to be disseminated. 相似文献
74.
Effect of Strong Anisotropy in Grain-Boundary Energy on Boundary Mobility in Abnormally Grown Grains
The growth of a large crystal into a fine-grained polycrystal of the same phase is considered through a two-dimensional model. The macroscopic driving force for growth depends only on the average energy of the grain boundaries of the polycrystalline matrix. The analysis reveals a dependence of the local driving force and effective mobility on the orientation of the interface between the large crystal and the matrix. The orientations with very low energy relative to the neighboring orientations also have low effective mobility. Applications are found in modeling of abnormal grain growth in ceramics and in experiments designed to measure the mobility of grain boundaries. 相似文献
75.
A new reconfigurable systolic multicomputer architecture is presented. The proposed architecture, called the Cylindrical Banyan Multicomputer (CBM), is based on the structure of a modified banyan network where every node of the network graph is composed of an application processor, a local memory and a communication processor, and network's inputs and outputs are merged (fused). The CBM has one of the lowest (cost) X (delay) among known multicomputer architectures based on regular networks. It is shown that a variety of computation structures such as pipelines, rings, and trees may be constructed and reconfigured in an optimal or a nearby optimal way on the CBM architecture, and that various basic algorithms can be executed very efficiently in a systolic manner. It is also shown that the CBM is an easily diagnosable and fault-tolerant system. 相似文献
76.
Exline Julie Juola; Baumeister Roy F.; Bushman Brad J.; Campbell W. Keith; Finkel Eli J. 《Canadian Metallurgical Quarterly》2004,87(6):894
Narcissistic entitlement impedes forgiveness in ways not captured by other robust predictors (e.g., offense severity, apology, relationship closeness, religiosity, Big Five personality factors), as demonstrated in 6 studies. Narcissistic entitlement involves expectations of special treatment and preoccupation with defending one's rights. In Study 1, entitlement predicted less forgiveness and greater insistence on repayment for a past offense. Complementary results emerged from Study 2, which used hypothetical transgressions, and Study 3, which assessed broad forgiveness dispositions. Study 4 examined associations with the Big Five, and Study 5 extended the findings to a laboratory context. Study 6 demonstrated that entitlement predicted diminished increases in forgiveness over time. Taken together, these results suggest that narcissistic entitlement is a robust, distinct predictor of unforgiveness. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
77.
The microwave drill is a novel process for creating shaped holes in nonconductive materials. Its inherent material selectivity makes the microwave drill ideally suited for the controlled removal of ceramic coatings from underlying metallic substrates. In this paper, it is shown that the microwave drill process can drill through ceramic thermal barrier coatings (TBCs) to uncover an array of simulated cooling holes. The concept, apparatus, and procedure for successful drilling are described, and the potential for use in the production of advanced gas turbine components is discussed. 相似文献
78.
79.
Presents a historical overview of the role of the National Institute of Mental Health in developing and using the behavioral sciences as the substantive base of its various programs of research, training and services. Major themes of research programs are illustrated with special reference to schizophrenia, brain-behavior relations, small-group interaction, collective behavior, and adaptation in stress. Training program development in the various mental health specialties is also described. Innovative models of interdisciplinary research training, involving the biological, psychological and social sciences are recommended to respond to complex research challenges in the mental health field. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Inverted peaks and strongly increased peaks have been reported and different explanations of these phenomena have been suggested[1,2]. The present communication discusses the peak shape distortions (“inverted” peaks, current oscillations) in terms of tangential movements of the mercury electrode surface. These distortions are explained similarly to the maxima in classical polarography: inhomogeneous polarization and inhomogeneous adsorption are considered as the two major forces causing the mercury surface movement and as a result, leading to the peak shape distortions. Experimental examples of the phenomena in aprotic and protic media and for organic and inorganic redox couples are given and explained in accordance with the proposed theory. 相似文献