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Fred Luthans 《组织行为杂志》2002,23(6):695-706
This essay draws from the emerging positive psychology movement and the author's recent articles on the need for and meaning of a positive approach to organizational behavior. Specifically, the argument is made that at this time, the OB field needs a proactive, positive approach emphasizing strengths, rather than continuing in the downward spiral of negativity trying to fix weaknesses. However, to avoid the surface positivity represented by the non‐sustainable best‐sellers, the case is made for positive organizational behavior (POB) to take advantage of the OB field's strength of being theory and research driven. Additional criteria for this version of POB are to identify unique, state‐like psychological capacities that can not only be validly measured, but also be open to development and performance management. Confidence, hope, and resiliency are offered as meeting such POB inclusion criteria. The overall intent of the essay is to generate some positive thinking and excitement for the OB field and ‘hopefully’ stimulate some new theory building, research, and effective application. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
3.
Schröder W Hornsmann I Pesch R Schmidt G Markert B Fränzle S Wünschmann S Heidenreich H 《Environmental monitoring and assessment》2007,133(1-3):495-505
The study was conducted to test the hypothesis that the regional variability of nitrogen (N) and metal accumulations in terrestrial ecosystems are due to historical and recent ways of landuse. To this end, two regions of Central Europe were selected for investigation: the Weser-Ems Region (WER) and the Euro Region Nissa (ERN). They were assumed to have land use-specific accumulation profiles. Thus, the metal and N accumulations in both regions were examined by means of geostatistically based comparative moss analysis. The sampling and chemical analysis of mosses were conducted in accordance with the convenient guidelines and methods, respectively. The spatial representativity of the sampling sites was computed by means of a land classification which was calculated for Europe by means of classification trees and GIS-techniques. The differences of deposition loads were tested for statistical significance with regard to time and space. The measurement values corroborated the decline of metal accumulation observed since the beginning of the European Metals in Mosses Surveys in 1990. The metal loads of the mosses in the ERN exceeded those in the WER significantly. The opposite holds true for the N concentrations: those in the WER were significantly higher than those in the ERN. The reduction of emissions from power plants, factories and houses was strongly correlated with the decline of deposition and bioaccumulation of metals. As proved by the European Metals in Mosses Surveys, this tendency is due to successful environmental policies. But no such success could be verified by monitoring the accumulation of N in mosses. 相似文献
4.
Bunge Michael Khknen Mika A. Rmisch Winfried Opel Matthias Vogler Susanne Walkow Fred Salkinoja-Salonen Mirja Lechner Ute 《Environmental science and pollution research international》2007,14(1):3-10
Background, Aims and Scope Sediments of the Spittelwasser creek are highly polluted with organic compounds and heavy metals due to the discharge of untreated
waste waters from the industrial region of Bitterfeld-Wolfen, Germany over the course of more than one century. However, relatively
few data have been published about the chloroorganic contamination of the sediment. This paper reports on the content of different
(chloro)organic compounds with special emphasis on polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F), and chlorobenzenes. Existing concepts for the remediation of Spittelwasser sediment include
the investigation of natural attenuation processes, which largely depend on the presence of an intact microbial food web.
In order to gain more insight in terms of biological activity, we analyzed the capacity of sediment microflora to degrade
organic matter by measuring the activities of extracellular hydrolytic enzymes involved in the biogeochemical cycling of carbon,
nitrogen, phosphorus and sulfur. Furthermore, the detection of physiologically active bacteria in the sediment, particularly
of those known for their capability to reductively dehalogenate organochlorine compounds, illustrates the potential for intrinsic
bioremediation processes.
Methods PCDD/F and chlorobenzenes were analyzed by gas chromatography(GC)/mass spectrometry and GC/flame ionization detection, respectively.
The activities of hydrolytic enzymes were determined from freshly sampled sediment layers using 4-methylumbelliferyl (MUF)
or 7-amino-4-methylcoumarin-conjugated model compounds and kinetic fluorescence measurements. Physiologically active bacteria
from different sediment layers were microscopically visualized by fluorescence in situ hybridization (FISH). Specific bacteria were identified by 16S rRNA gene amplification and sequencing.
Results and Discussion The PCDD/F congener profile was dominated by dibenzofurans. In addition, the presence of specific tetra and pentachlorinated
dibenzofurans supported the assumption that extensive magnesium production was one possible source for the high contamination.
A range of other chloroorganic compounds, including several isomers of chlorobenzenes, hexachlorocyclohexane and 1,1,1-trichloro-2,2-bis
(p-chloro-phenyl)ethane (DDT), was present in the sediment. Activities of extracellular hydrolytic enzymes showed a strong
decrease in those sediment layers that were characterized by high contents of absorbable organic halogen (AOX), indicating
disturbed organic matter decay. Interestingly, an abnormal increase of cellulolytic enzyme activities below the organochlorine-rich
layers was observed, possibly caused by residual cellulose from discharges of sulfite pulping wastes. FISH revealed physiologically
active bacteria in most sediment layers from the surface down to the depth of about 60 cm, including members of Desulfitobacterium (D.) and Sulfurospirillum. The presence of D. dehalogenans was confirmed by its partial 16S rRNA gene sequence.
Conclusions Results of chemical sediment analyses demonstrated high loads of organochlorine compounds, particularly of PCDD/F. Several
years after stopping the waste water discharge to Spittelwasser creek, this sediment remains a main source for pollution of
the downstream river system by way of the ongoing mobilization of sediment during high floods. As indicated by our enzyme
activity measurements, the decomposition potential for organic matter is low in organochlorine-rich sediment layers. In contrast,
the comparably higher enzyme activities in less organochlorine-polluted sediment layers as well as the presence of physiologically
active bacteria suggest a considerable potential for natural attenuation.
Recommendations and Perspectives From our data we strongly recommend to explore the degradative capacity of sediment microorganisms and the limits for in situ activity towards specific sediment pollutants in more detail. This will give a sound basis for the integration of bioremediation
approaches into general concepts to reduce the risk that permanently radiates from this highly contaminated sediment.
Submission Editor: Dr. Henner Hollert (Henner.Hollert@urz.uniheidelberg.de) 相似文献
5.
The situation and the latest findings of forest damage research in Germany are discussed. A newly developed concept for this research is described. This concept allows to identify the drawbacks of the recent damage research concept but also the integration of results compiled up to now. The importance for including natural occurring stress factors such as climate, soil conditions or local situation of individual species is outlined. 相似文献
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Ingrid Witters Hans Van Bokhoven A. Goossens Frans-André Van Assche Jean-Pierre Fryns 《黑龙江环境通报》2001,21(13):1119-1122
We report the prenatal diagnosis at 16 weeks' gestation of bilateral split-hand/split-foot malformation (SHSFM) with severe lobster claw deformity of hands and feet in a male fetus without associated malformations. A minor manifestation of SHSFM was present in the father with only mild bilateral foot involvement (syndactyly I–II; cleft II–III; left cutaneous syndactyly III–IV). Mutation analysis of the p63 gene on chromosome 3q27 showed a missense mutation 577A→G (predicting amino acid substitution K193E) in the father. This mutation has not been reported so far in SHSFM but resembles the previously reported 580A→G (predicting amino acid substitution K194E) in a family with SHSFM. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
8.
Van der Eerden LJ Lekkerkerk LJ Smeulders SM Jansen AE 《Environmental pollution (Barking, Essex : 1987)》1992,76(1):1-9
Three-year-old Douglas firs (Pseudotsuga menziesii) were fumigated with 180 microg m(-3) NH3 or clean (charcoal-filtered) air. During these fumigations the plants received 15 mm artificial rain weekly, supplemented with 20, 500 or 2500 micromol litre(-1) (NH4)2SO4. Exposure to NH3 and NH4+ for 14 weeks resulted in a change of the nutrient status of the needles. The most remarkable effect was the increase in the N/K ratio, due to both uptake of N and leaching of K. The action of NH3 was stronger than that of NH4+. Both NH3 and (NH4)2SO4 affected the epicuticular wax layer and decreased mycorhiza frequency. Following fumigation and artificial rain treatments, needles were incubated for 8 h in a medium containing 0, 50, 250, 500 and 2500 micromol litre(-1) (NH4)2SO4. Almost no exchange of Ca, Mg and K for NH4+ was found. Therefore this ion exchange probably explains only a minor part of the changes in nutrient status of the whole trees. 相似文献
9.
Le Nguyen Truc Thinh Nguyen An Ha Nguyen Thi Vinh Tien Nguyen Dinh Lam Nguyen Duc Hong Nguyen Van Tuan Nguyen Tat Hanh Ta Van Khanh Nguyen Ngoc Thanh Nguyen Ngoc Hens Luc 《Environment, Development and Sustainability》2022,24(10):12427-12445
Environment, Development and Sustainability - The recent growth of agriculture, industry and urban areas in Vietnam requires a large amount of water consumption as a production factor. This paper... 相似文献
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