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1.
[Correction Notice: An erratum for this article was reported in Vol 14(1) of Journal of Occupational Health Psychology (see record 2008-19186-009). This particular study was based upon a unique database (the Springlife database), with repeated questionnaire self-reports from hospital staff in the ?rebro Regional Hospital in Sweden regarding work environment and mental health in the years 1994, 1995, 1997, 1999, and 2001. The Springlife database was referred to in the text and references of the article noted above, but it should have been more clearly acknowledged. Herewith the authors want to make this late acknowledgement. The database actually started in the fall of 1993 with the regional hospital's physicians and continued with all hospital staff during the spring 1994.] Swedish hospital personnel were followed over an 8-year period, characterized by staff redundancies and restructuring processes. Self-rated and administrative data sets from 1994 to 2001 allowed for studying long-term consequences of organizational instability for staff health and work conditions. The aim was to identify, on a work-unit level, trends in work and health conditions and their interdependence. Regression analysis showed a downward trend in mental health and an upward trend in long-term sick leave. Increasing trends of work demands were accompanied by deteriorating mental health, and decreasing time to plan work showed the strongest association with increasing long-term sick leave. Job satisfaction and support were decreasing. A stable short-term sick leave rate over years related to lack of support. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
Demands on workload and work efficiency have increased because of ongoing global changes in health care organizations. Assessing and evaluating effects of changes on organizational and individual well-being require valid and reliable methods. Questionnaires from 3 large health care studies were used to develop instruments for work quality and health. Study 1 included 2,935 participants from all occupational groups. Study 2 sampled 3,545 nurses and midwives. Participants in Study 3 consisted of 3,506 employees at a large hospital. Variable fields of work quality, health and well-being, and modifying factors were factor analyzed with replicated structures in new samples, including 6 factors of work quality, 5 health factors, and 2 modifying factors. All except 2 factors had high internal consistency (Cronbach's α?=?.69–84) and low factor intercorrelations within areas. Social climate (but not individual resources) had, according to our model, a modifying effect on the work-health interaction (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Microfluidic gradient-generating device for pharmacological profiling   总被引:1,自引:0,他引:1  
We describe an on-chip microfluidic gradient-generating device that generates concentration gradients spanning nearly 5 orders of magnitude starting from a single concentration. The exiting stream of drugs held at different concentrations remains laminar in a recording chamber and can be presented as 24 discrete solutions to a cell-based sensor. The high-performance characteristics of the device are demonstrated by pharmacological screening of voltage-gated K+ channels (hERG) and ligand-gated GABA(A) receptors using scanning-probe patch-clamp measurements. Multiple data point dose-response curves and IC50 and EC50 values were rapidly obtained, typically in less than 30 min, through its combined functionality of gradient generation and open-volume laminar flow. The device facilitates rapid pharmacological profiling of ion channel and GPCR effectors and enables the acquisition of large numbers of data points with minute sample consumption and handling.  相似文献   
4.
The structures of organic phosphorous (P) compounds in aquatic sediments are to a large extent unknown although these compounds are considered to play an important role in regulating lake trophic status. To enhance identification of these compounds, a liquid chromatography (LC) method for their separation was developed. The stationary phase was porous graphitic carbon (PGC), and the mobile phases used in the gradient elution were compatible with both inductive coupled plasma atomic emission spectroscopy (ICP-AES) and electrospray ionization tandem mass spectrometry (ESI-MS/MS). With LC-ICP-AES, eight different P containing peaks could be observed in the P chromatogram indicating that at least eight different P compounds were separated. With the setup of an information dependent acquisition (IDA) with ESI-MS/MS, the mass over charge ( m/ z) of compounds containing a phosphate group (H 2PO 3 (-), m/ z 97) could be measured and further fragmentation experiments gave additional information on the structure of almost 40 separated P compounds, several were verified to be nucleotides. ICP-AES was very suitable in the development of the LC method and allowed screening and quantification of P compounds. The presented LC-ESI-MS/MS technique was able to identify several sediment organic P compounds.  相似文献   
5.
A new type of crystalline silicon solar cell is described. Superficially similar to a photoelectrochemical cell a liquid electrolyte creates a depletion (inversion) layer in an n-type silicon wafer, however no regenerative redox couple is present to ferry charge between the silicon and a counter electrode. Instead holes trapped in the electrolyte-induced inversion layer diffuse along the layer until they come to widely spaced grid lines, where they are extracted. The grid lines consist of a single-walled carbon nanotube film etched to cover only a fraction of the n-Si surface. Modeling and simulation shows the inversion layer to be a natural consequence of the device electrostatics. With electronic gating, recently demonstrated to boost the efficiency in related devices, the cell achieves a power conversion efficiency of 12%, exceeding the efficiency of dye sensitized solar cells.  相似文献   
6.
There have been few prospective studies of the impact of workplace interventions on employee and organizational well-being within health care settings. This study was conducted at a large regional hospital in Sweden in 1994 with a follow-up in 1995. Effects of a structured organizational and staff intervention program on perceived psychosocial work quality, supporting resources and self-reported health and well-being were evaluated. Based on department-specific results from the baseline assessment in 1994, each department formulated their own improvement goals. They also made their own decisions on relevant improvement activities. Since there was no formal reference group in this study, departments with high and low rating levels, respectively, with regard to intervention activities were compared. Despite an overall worsening in most of the measures most likely due to a notice of 20% staff reduction prior to the follow-up assessment, the intervention appeared to have attenuated negative changes in the high as compared with the low activity group. Manager-rated impact of the program as well as positive staff attitudes and staff involvement in the enhancement process were identified as important determinants for more favourable changes. The study points out the relevance of structured workplace interventions for organizational and employee well-being especially in times of cut-backs and organizational turmoil. Department-specific factors will determine the impact of such programs. The study indicates that the psychosocial impact of personnel cut-backs in health care may be attenuated through management initiatives.  相似文献   
7.
Since April 1992 the arterial switch operation (ASO) has been the treatment of neonates with transposition of the great arteries (TGA) at Rigshospitalet, Copenhagen. Thirteen mature neonates with TGA underwent ASO. Ten patients had simple TGA, two had TGA associated with a ventricular septal defect (VSD), and one had TGA with VSD and in addition moderate right ventricular hypoplasia. All patients survived the operation and are still alive. Perioperative bleeding was a problem in three cases. Eleven patients had an uncomplicated postoperative course. One patient had peri- and postoperative left ventricular failure and was reoperated after three months for a residual VSD. One child developed renal failure and needed peritoneal dialysis. The patients have been followed for 5.5 (range 0-12) months, they are all in good condition and thriving well. The presented early results after ASO justify continued recommendation of ASO as the operation of choice for TGA in neonates at Rigshospitalet.  相似文献   
8.
High efficiency graphene solar cells by chemical doping   总被引:1,自引:0,他引:1  
We demonstrate single layer graphene/n-Si Schottky junction solar cells that under AM1.5 illumination exhibit a power conversion efficiency (PCE) of 8.6%. This performance, achieved by doping the graphene with bis(trifluoromethanesulfonyl)amide, exceeds the native (undoped) device performance by a factor of 4.5 and is the highest PCE reported for graphene-based solar cells to date. Current-voltage, capacitance-voltage, and external quantum efficiency measurements show the enhancement to be due to the doping-induced shift in the graphene chemical potential that increases the graphene carrier density (decreasing the cell series resistance) and increases the cell's built-in potential (increasing the open circuit voltage) both of which improve the solar cell fill factor.  相似文献   
9.
A lag-stabilized, force feedback controller for damping initial and residual oscillations of a planar, cantilevered flexible arm has been analytically developed and experimentally implemented on a commercial robot. The controller feeds back force sensor measurements that are delayed in time and proportional to the displacement (angular orientation) of the arm in order to damp the oscillation. As a result of the lag (contrary to popular belief), the controlled robot system is stable and provides tunable performance on a Cincinnati Milacron T3-786 robot.  相似文献   
10.
The absorption of Zn from a lupin (Lupinus angustifolius) milk fortified with Ca, a bread containing lupin flour (230 g/kg), a sauce containing lupin flour and a sauce containing a lupin-protein isolate was determined in humans by measuring the whole-body retention of radioisotope from meals labelled with 0.02 MBq 65Zn, allowing for endogenous excretion of Zn, after 14 d. The absorption of Zn from the Ca-enriched milk (16.2%) and the bread made with lupin flour (27.0%) was similar to literature figures for comparable soya-bean products. The absorption from composite meals made with lupin flour (28.2%) and protein isolate (32.7%) was significantly higher than that reported for comparable soya-bean products. In a second experiment the absorption of Zn from a lupin-milk base and a soya-bean-milk base was compared with that from Ca-supplemented bases. The absorption of Zn from the lupin-milk base (26.3%) was significantly higher than from the soya-bean-milk base (17.6%), and neither was significantly altered by the addition of Ca. Overall the absorption of Zn from lupin-protein foods was found to be higher than from comparable soya-bean products. Lupin milk could be an attractive alternative to soya-bean milk for infant formulas.  相似文献   
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