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91.

Background

Whether burnout is a distinct phenomenon rather than a type of depression and whether it is a syndrome, limited to three “core” components (emotional exhaustion, depersonalization and low personal accomplishment) are subjects of current debate. We investigated the depression-burnout overlap, and the pertinence of these three components in a large, representative sample of physicians.

Methods

In a cross-sectional study, all Austrian physicians were invited to answer a questionnaire that included the Major Depression Inventory (MDI), the Hamburg Burnout Inventory (HBI), as well as demographic and job-related parameters. Of the 40093 physicians who received an invitation, a total of 6351 (15.8%) participated. The data of 5897 participants were suitable for analysis.

Results

Of the participants, 10.3% were affected by major depression. Our study results suggest that potentially 50.7% of the participants were affected by symptoms of burnout. Compared to physicians unaffected by burnout, the odds ratio of suffering from major depression was 2.99 (95% CI 2.21–4.06) for physicians with mild, 10.14 (95% CI 7.58–13.59) for physicians with moderate, 46.84 (95% CI 35.25–62.24) for physicians with severe burnout and 92.78 (95% CI 62.96–136.74) for the 3% of participants with the highest HBI_sum (sum score of all ten HBI components). The HBI components Emotional Exhaustion, Personal Accomplishment and Detachment (representing depersonalization) tend to correlate more highly with the main symptoms of major depression (sadness, lack of interest and lack of energy) than with each other. A combination of the HBI components Emotional Exhaustion, Helplessness, Inner Void and Tedium (adj.R2 = 0.92) explained more HBI_sum variance than the three “core” components (adj.R2 = 0.85) of burnout combined. Cronbach’s alpha for Emotional Exhaustion, Helplessness, Inner Void and Tedium combined was 0.90 compared to α = 0.54 for the combination of the three “core” components.

Conclusions

This study demonstrates the overlap of burnout and major depression in terms of symptoms and the deficiency of the three-dimensional concept of burnout. In our opinion, it might be preferable to use multidimensional burnout inventories in combination with valid depression scales than to rely exclusively on MBI when clinically assessing burnout.  相似文献   
92.
Cell cultures of Corydalis sempervirens adapted to growth in the presence of 5 millimolar glyphosate overproduce the herbicide's target enzyme, 5-enolpyruvylshikimate 3-phosphate (EPSP) synthase, 30- to 40-fold. In vitro translation of total RNA and poly(A)-RNA coupled with immunoprecipitation showed that the protein is synthesized as a precursor of relative molecular weight (Mr) 53900 ± 900 as compared to Mr 45500 ± 1000 of the mature enzyme. Translatable activity of mRNA for EPSP-synthase in glyphosate-adapted cultures is tenfold higher than in nonadapted cultures.  相似文献   
93.
Summary In steady state, attained by continuous aeration after oxygen saturation of water in a bubble column, vertical composition distribution of liquid and gas phases has been determined. It has been assumed that, as a result of absorption at the bottom of the column, desorption in the upper section and vertical dispersion of dissolved oxygen flux, a closed oxygen circulation is created. Determination of the axial dispersion coefficient from hydrodynamic and oxygen transfer data verifies the mathematical model proposed. The results allow conclusions to be drawn about supersaturation and desorption and other phenomena expected in biological systems.Abbreviations C[-] Dimensionless oxygen concentration Unit=0.21 bar oxygen partial pressure or dissolved oxygen level in equilibrium with latter - E[m2/s] Axial dispersion coefficient - F[m2] Horizontal cross-section area - k L a[s-1] Overall oxygen transfer coefficient - u; u 2[m/s; cm/s] Superficial velocity: related to state of bubbles leaving the sparger - x; x atm[-] Signal registered in the experiment; signal recorded in O2 saturated water, or water vapor saturated air stream, at temperature identical to the experiment under atmospheric pressure - y[m] Water column height - [s-1] Dimensionless oxygen flux Indices a asorption - d desorption - g gas - l liquid - k dispersion - m measured value/in the case of hydrodynamically measured E/ Dedicated to Professor Dr. H. J. Rehm on the occasion of his 60th birthday  相似文献   
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A culture system is described to grow mycorrhizal plants which allows experimental measurements to be made on mycorrhizae, and a portion of intact ectomycorrhizal fungi while in symbiosis, but growing apart from the rooting medium and host roots. A portion of the extramatrical hyphae is kept apart from the rooting medium by a restrictive passageway between the root and fungal chambers. The passageway is small enough to restrict coniferous fine roots to the root chamber, but large enough to allow fungal hyphae to grow out of the root chamber onto pre-weighed glass fiber filter paper situated in the fungal chambers. The pre-weighed filter paper allows for gravimetric estimation of the hyphal mass in the fungal chamber. The pieces of the modular Root-Mycocosm can be assembled in various configurations with one or two seedling chambers and one, two or three fungal chambers. Ponderosa pine (Pinus ponderosa Laws.) seedlings were inoculated withHebeloma crustuliniforme (Bull.: St. Amans) Qúel in either commercial-vermiculite inoculum or in plastic growth-pouches and grown in the Root-Mycocosm. Hyphae were allowed to grow into the fungal chambers and after four weeks, amounted to 5.5±0.81 SE and 6.4±1.5 SE mg for pouch and commercial inoculum techniques, respectively.Copies of a detailed design drawing can be obtained by writing to the authors.  相似文献   
98.
Summary A continuous fixed-bed denitrification system operating with high capacity and 100% efficiency has been developed for laboratory scale experiments. The data required for stable operation were obtained by determination of the kinetic constants of the system.  相似文献   
99.
The ultrastructure of the head end and surface structure of the cuticle of Syphacia petrusewiczi, S. nigeriana, S. frederici and S. stroma was studied. These species may be easily separated on the basis of the differences in their morphology: S. frederici possesses longitudinal septa on the body surface, a row of denticles on each of the three main teeth, and cervical alae; S. nigeriana has longitudinal septa and denticles but lack cervical alae; S. petrusewiczi has longitudinal septa and cervical alae but lacks denticles; S. stroma lacks these three characters.  相似文献   
100.

Peatlands are characterized by their large carbon (C) storage capacity and represent important C sinks globally. In southern Chile, young peatlands (few centuries old) have originated due to clearcutting or fire at forest sites with high precipitation on poorly drained soils. These novel ecosystems are called anthropogenic peatlands here. Their role in the regional C cycle remains largely unknown. Here, we present 18 months of eddy covariance measurements of net ecosystem exchange (NEE) of carbon dioxide (CO2) in an anthropogenic peatland in northern Chiloé Island, part of which is kept undisturbed for 30–40 years, by excluding human uses, and another section of the same peatland that has been disturbed by cattle grazing and Sphagnum moss extraction. Gross primary productivity (GPP) and ecosystem respiration (Reco) were modeled from NEE, based on measured photosynthetically active radiation and air temperature, separately for each section of the peatland. Uncertainties of the annual flux estimates were assessed from the variability of modelled fluxes induced by applying different time-windows for model development between 10 and 20 days. The undisturbed area of the peatland was on average (±?SD) a larger net CO2 sink (NEE?=???135?±?267 g?CO2?m?2?year?1) than the disturbed area (NEE?=???33?±?111 g?CO2?m?2?year?1). These NEE CO2 balances are small even though GPP and Reco were larger compared with other peatlands. Reco had a direct relationship with water table depth (from soil surface) and a negative relationship with soil water fraction. Our results show that the disturbance by moss extraction and cattle grazing is likely to reduce the CO2 sink function of many anthropogenic and natural peatlands on Chiloé Island, which are subjected to the same impacts.

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