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61.
This study contrasts the graduate training and subsequent careers of a cohort of United States-born foreign medical graduates (USFMGs) and foreign medical graduates (FMGs) who were in training positions in Connecticut in 1964 and who were located in 1971. The data suggest that although USFMGs were foreign-educated, they had certain advantages--both cultural and administrative--in hospital training positions which helped them to pursue different career alternatives than FMGs. However, the data further suggest that they retained characteristics of their foreign training which continued to differentiate them from United States medical graduates (USMGs).  相似文献   
62.
Photovoltaic power systems are potentially well suited to commercial demand side management applications because the solar resource coincides well with the typical weekday load profile of many types of commercial utility customers. To investigate this potential a 13 kW AC PV system has been installed by Niagara Mohawk near Albany, NY, USA. The results from two years of operation show that photovoltaics can play an important role in reducing a building's daytime peak demand, especially when that peak demand is driven by air conditioning loads  相似文献   
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PURPOSE: This study focuses on the curvature and inclination of the lingual surfaces of the maxillary anterior teeth from the transition point on the cingulum to the incisal edge. MATERIALS AND METHODS: On 32 sets of mounted casts, 768 measurements were made of the curvature of the lingual surfaces utilizing radius gauges. The inclination of the lingual surface relative to the occlusal plane was recorded. The relationship of the incisal edge of the mandibular teeth to the transition point on the cingulum of the maxillary teeth was determined. Centric occlusion contact was noted on each tooth. RESULTS: Significant differences were found between the measured areas of any one tooth and between the types of teeth. The average radius ranged from 20.5 mm on the mesial ridge of the canine to 5.3 mm in the fossa of the central. The average inclination of the lingual surfaces was 46 degrees. In centric occlusion, 97% of the canines and 59% of the centrals and laterals were in contact with the opposing teeth. These contacts occurred 2.8 mm incisal to the transition point. The centrals contracted two opposing teeth (45%), and canines contacted one opposing tooth (53%). CONCLUSIONS: The function and curvature of the incisor teeth vary considerably from those of the canines. Overcontouring the lingual surfaces of the maxillary incisors to gain contact is not normal and may be detrimental.  相似文献   
65.
There is some controversy over whether or not a discrete site that integrates vomiting activities in somatic and autonomic nerves is present in the medulla oblongata. On the basis of our previous studies, we hypothesized that the temporal patterns of muscle contractions in vomiting are generated by a central pattern generator in the retrofacial area of the rostral medulla. To investigate this hypothesis further, the effects of electrical and chemical lesions of the medullary area were observed in decerebrate paralyzed dogs. Efferent activities of the phrenic and abdominal muscle nerves were recorded to recognize fictive vomiting. The right half of the medulla oblongata was transversely severed about 3 mm rostral to the obex. Fictive vomiting responses to vagal stimulation still appeared after hemisection in all 11 dogs. In addition, stimulation of the contralateral reticular area dorsomedial to the retrofacial nucleus produced fictive vomiting even after hemisection. An electrical lesion or injection of kainic acid (0.5-1.0 microl) was applied at the point where reticular stimulation induced fictive vomiting. After this destruction, no activities that corresponded to fictive vomiting could be induced by stimulation of vagal afferents or the reticular site. Salivation was decreased by hemisection, and decreased further, but was not completely abolished, with destruction of the reticular area. Kainic acid is known to selectively destroy neural cell bodies. Therefore, we concluded that neuronal somata in the reticular formation dorsomedial to the retrofacial nucleus play an essential role in the central patterning of vomiting activities in peripheral motor nerves.  相似文献   
66.
The disclosure of the mechanisms of nanoparticle interaction with specific intracellular targets represents one of the key tasks in nanobiology. Unmodified luminescent semiconductor nanoparticles, or quantum dots (QDs), are capable of a strikingly rapid accumulation in the nuclei and nucleoli of living human cells, driven by processes of yet unknown nature. Here, it is hypothesized that such a strong tropism of QDs could be mediated by charge-related properties of the macromolecules presented in the nuclear compartments. As the complex microenvironment encountered by the QDs in the nuclei and nucleoli of live cells is primarily presented by proteins and other biopolymers, such as DNA and RNA, the model of human phagocytic cell line THP1, nuclear lysates, purified protein, and nucleic acid solutions is utilized to investigate the interactions of the QDs with these most abundant classes of intranuclear macromolecules. Using a combination of advanced technological approaches, including live cell confocal microscopy, fluorescent lifetime imaging (FLIM), spectroscopic methods, and zeta potential measurements, it is demonstrated that unmodified CdTe QDs preferentially bind to the positively charged core histone proteins as opposed to the DNA or RNA, resulting in a dramatic shift off the absorption band, and a red shift and decrease in the pholuminescence (PL) intensity of the QDs. FLIM imaging of the QDs demonstrates an increased formation of QD/protein aggregates in the presence of core histones, with a resulting significant reduction in the PL lifetime. FLIM technology for the first time reveals that the localization of negatively charged QDs to their ultimate nuclear and nucleolar destinations dramatically affects the QDs' photoluminescence lifetimes, and offers thereby a sensitive readout for physical interactions between QDs and their intracellular macromolecular targets. These findings strongly suggest that charge-mediated QD/histone interactions could provide the basis for QD nuclear localization downstream of intracellular transport mechanisms.  相似文献   
67.
1. Familiarize yourself with the vital resources in your community. 2. Assist individuals in focusing on "real life" and practical problem issues. Maintain a focus on recovery and rehabilitation issues. 3. Remember: longer-term vocational successes depend on individual choice, encouragement, and supports.  相似文献   
68.
Recent agreements between the Democratic People's Republic of Korea (DPRK) and the other countries involved in the six-party talks on the future of the DPRK's nuclear weapons program have focused attention on the North Korean energy sector, and, specifically, what the international community can or should do to assist the DPRK in energy sector redevelopment. During two visits to North Korea in 1998 and 2000, a team of American and North Korean researchers conducted a unique rural energy use survey in a flood-affected rural village in the DPRK—the farming village of Unhari. The information gathered during the survey has important implications on how to properly approach the ongoing rural energy crisis in the DPRK, and, more broadly, to provide overall energy sector assistance. The results of the Unhari survey are described briefly, followed by suggestions of internal policy and legal reforms, approaches to international cooperation, key and attractive energy sector technologies and processes for energy sector redevelopment in the DPRK.  相似文献   
69.
BACKGROUND: Previous studies showed differences in fatty acid (FA) and antioxidant profiles between organic and conventional milk. However, they did not (a) investigate seasonal differences, (b) include non‐organic, low‐input systems or (c) compare individual carotenoids, stereoisomers of α‐tocopherol or isomers of conjugated linoleic acid. This survey‐based study compares milk from three production systems: (i) high‐input, conventional (10 farms); (ii) low‐input, organic (10 farms); and (iii) low‐input non‐organic (5 farms). Samples were taken during the outdoor grazing (78 samples) and indoor periods (31 samples). RESULTS: During the outdoor grazing period, on average, milk from the low‐input systems had lower saturated FAs, but higher mono‐ and polyunsaturated FA concentrations compared with milk from the high‐input system. Milk from both the low‐input organic and non‐organic systems had significantly higher concentrations of nutritionally desirable FAs and antioxidants—conjugated linoleic (60% and 99%, respectively) and α‐linolenic (39% and 31%, respectively) acids, α‐tocopherol (33% and 50%, respectively) and carotenoids (33% and 80%, respectively)—compared with milk from the high‐input system. Milk composition differed significantly between the two low‐input systems during the second half of the grazing period only; with milk from non‐organic cows being higher in antioxidants, and conjugated linoleic acid, and that from organic cows in α‐linolenic acid. In contrast, few significant differences in composition were detected between high‐input and low‐input organic systems when cows were housed. CONCLUSIONS: Milk composition is affected by production systems by mechanisms likely to be linked to the stage and length of the grazing period, and diet composition, which will influence subsequent processing, and sensory and potential nutritional qualities of the milk. Copyright © 2008 Society of Chemical Industry  相似文献   
70.
Emil Otto Hoppé established himself as the leading producer of photographic portraits in Edwardian London, a position he augmented until the mid-1920s. Particular aesthetic, psychological and philosophical ideas undergirded his practices – practices which, in some respects, were then unconventional. His portrait work helped him to achieve some celebrity as an influential cultural figure, and this status in turn advanced his career as a portrait maker. Three important determinants of Hoppé’s portrait output are identified and elaborated upon: ‘The Maker’ (Hoppé himself); ‘Patronage’ (the actual or assumed demands of customers, including sitters); and – an entity that is less easy to define – ‘The Public’. Hoppé claimed, of certain eminent figures, that he had made ‘the recognised face’, and the sense of public recognition here implies that the likeness must combine intense insight with extensive circulation in the illustrated press. Viewed in retrospect, the range of Hoppé’s portraits – from such leading politicians as Philip Snowden, through such society beauties as Lady Hazel Lavery, to artists, including Jacob Epstein and Rudyard Kipling – punctuated a particular period of history, the cultural moment at which emerging aspects of twentieth-century modernity could be discerned. Exemplary in this respect, despite its unusual collage nature, is Hoppé’s depiction of the Italian Futurist Filippo Tommaso Marinetti.  相似文献   
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