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121.
122.
1H-N.M.R. Spectroscopic Investigations on Innermolecular Mobility of Substituted 1,3-Diazabutadienes Two isomerization processes in substituted 1,3-diazabutadienes can be observed by the method of dynamic n.m.r. spectroscopy. From coalescence phenomena the free activation enthalpies ΔG± are determined and discussed with regard to substituent effects and solvent dependency.  相似文献   
123.
The literature on chronic diseases recognizes the role of illness cognition as a mediator between stress and illness. Few conceptualizations and instruments, however, give an indication of both unfavorable and favorable ways of adjusting to an uncontrollable long-term stressor, such as a chronic disease. The authors propose 3 generic illness cognitions that reflect different ways of reevaluating the inherently aversive character of a chronic condition: helplessness as a way of emphasizing the aversive meaning of the disease, acceptance as a way to diminish the aversive meaning, and perceived benefits as a way of adding a positive meaning to the disease. A self-report instrument, the Illness Cognition Questionnaire, was developed to assess these cognitions across different chronic diseases. The results support the reliable and valid assessment of these illness cognitions in patients with rheumatoid arthritis and multiple sclerosis and indicate the maladaptive function of helplessness and the adaptive function of acceptance and perceived benefits for the long-term physical and psychological health of patients with a chronic disease. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
124.
This paper analyses the determinants of different innovation types in Germany using the IAB (Institut für Arbeitsmarkt- und Berufsforschung—Institute for Employment Research, Nuremberg) Establishment Panel 2006 to 2012 and merged regional data from various sources. The aim of the study is to test the empirical evidence of regional and firm-specific effects on innovations. For the empirical analysis variables of three dimensions are considered: availability and quality of local inputs, knowledge spillover, efficiency of regional innovation system and intra-firm capacity. The effects of these variables are estimated using three-level random effect logit models which account for the clustered and longitudinal structure of the data. In the focus is the empirical analysis of the expected impacts of regional and firm-specific factors on various categories of innovation activities in Germany. The differences between the various kinds of innovations became important when considering the regional and firm-specific variables in detail. While for radical innovations the unemployment rate, the share of MINT graduates, the R&D expenditures and industry’s regional concentration have significant, but relatively small impacts, for other types of innovation the regional variables are insignificant. Overall the empirical results show that the regional intra-class correlation is small and the firm-specific variables are crucial for modelling innovation activities in Germany and dominate the regional dimension.  相似文献   
125.
PURPOSE: The purpose of this study was to evaluate joint position sense (JPS) in patients with posttraumatic glenohumeral instability. MATERIALS AND METHODS: In 28 patients with posttraumatic instability and in a matched control group of 30 subjects proprioception capability was evaluated. For documentation of proprioception an angle reproduction test (ART) was performed with which joint positions sense (JPS) was measured for abduction, flexion, and rotation in three angles each. RESULTS: In both groups there was a significant better JPS with visual control than without. In contrast to the control group the patients were not able to increase angle reproduction capability without visual control when comparing positions below shoulder level with positions at or above shoulder level. When comparing the patients to the controls there were differences in most of the ARTs with worse results in the patient group. These differences were significant in 150 degrees flexion with and without visual control, in 150 degrees abduction without and in 100 degrees abduction with visual control. For rotation there were trends for almost all joint positions, however, the differences were significant only in the -45 position. When comparing the noninjured contralateral shoulder of the patients with the control group, there still were differences. Again these were not in all joint positions significant, but significant worse JPS could be demonstrated in 150 degrees abduction without visual control, 50 degrees flexion without visual control, -45 degrees rotation without and 0 degrees rotation with visual control. CONCLUSIONS: A proprioceptive deficit can be documented in patients with posttraumatic glenohumeral instability. This may be one reason for permanent instability. The contralateral joint also shows reduction in joint position sense. For consecutive treatment as well as for rehabilitation both shoulder joint should be addressed.  相似文献   
126.
We report a young musician who experienced transient ischemic attacks during trumpet playing. Cardiovascular examination revealed a patent foramen ovale; Doppler ultrasound of the middle cerebral arteries detected microembolic signals with increased rates during trumpet playing and Valsalva maneuver. After operative occlusion of the foramen ovale, the symptoms disappeared and no microembolic signals could be detected.  相似文献   
127.
A speed observer for induction machines without rotational transducers is presented. In contrast to known adaptive observer strategies, the proposed scheme uses-beside the conventional current difference-its integral and a new pair of stretch-turn operators not only to avoid the known instability region at braking but to obtain furthermore a constant gain. To ensure operation with very low stator frequencies, an elimination of parasitic dc components is presented additionally. Characteristics are explained and verified by measurements.  相似文献   
128.
This paper discusses the cryogenic mechatronic development of the Focal Plane Chopper (FPC) mechanism in the Heterodyne Instrument for the Far Infrared (HIFI) which is one of the science instruments on board the Herschel space telescope. The extreme cryogenic environment, in which the mechanism has to operate, places a number of constraints on the mechatronic design of the instrument. The paper gives an overview of cryogenic design issues applicable to the development of the FPC and provides solutions to the problems encountered.  相似文献   
129.
The ability to rise from a chair or bed is critical to an individual's quality of life because it determines functional independence. This study was to investigate the effect of bed height and use of hands on trunk angular velocity and trunk angles during the sit-to-stand (STS) performance. Twenty-four older persons (median age 74 years) were equipped with a body-fixed gyroscopic sensor and stood up from a bed adjusted to different heights, with and without the use of hands at each height. Peak angular velocity and trunk range of motion decreased with increasing bed height (all p ≤ 0.038) and were lower using hands during STS transfer indicating less effort. In conclusion, gyroscopic sensor data of the STS transfer of older persons show differences as an effect of bed height and use of hands. These results provide the rationale for recommending a relatively high bed height for most of the older persons.  相似文献   
130.
Determining the exact location of buried waste trenches is an important step in the characterization and remediation of certain hazardous waste sites. Remotely sensed data offers a rich source of information for accomplishing this task. This paper presents an investigation of buried waste trenches located at Oak Ridge National Laboratory (ORNL) using thermal remote sensing. A comparison of historical aerial photography and recently collected thermal imagery reveals a thermal signature which coincides with the precise locations of buried waste trenches. Statistical analysis of extensive ground measurements shows a clear thermal difference between the trench and control areas, with the trenches exhibiting cooler temperatures and greater soil moisture. By incorporating the imagery-derived information into site remediation plans, ORNL realized a cost avoidance of more than U.S. $5 000 000. Similar benefits can be anticipated at other DOE waste sites.  相似文献   
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