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We introduce the notion that the energy of individuals can manifest as a higher‐level, collective construct. To this end, we conducted four independent studies to investigate the viability and importance of the collective energy construct as assessed by a new survey instrument—the productive energy measure (PEM). Study 1 (n = 2208) included exploratory and confirmatory factor analyses to explore the underlying factor structure of PEM. Study 2 (n = 660) cross‐validated the same factor structure in an independent sample. In study 3, we administered the PEM to more than 5000 employees from 145 departments located in five countries. Results from measurement invariance, statistical aggregation, convergent, and discriminant‐validity assessments offered additional support for the construct validity of PEM. In terms of predictive and incremental validity, the PEM was positively associated with three collective attitudes—units' commitment to goals, the organization, and overall satisfaction. In study 4, we explored the relationship between the productive energy of firms and their overall performance. Using data from 92 firms (n = 5939employees), we found a positive relationship between the PEM (aggregated to the firm level) and the performance of those firms. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
44.

Objectives

We aimed to compare cell-based NIPT (cbNIPT) to chorionic villus sampling (CVS) and to examine the test characteristics of cbNIPT in the first clinical validation study of cbNIPT compared to cell-free NIPT (cfNIPT).

Material and Methods

Study 1: Women (N = 92) who accepted CVS were recruited for cbNIPT (53 normal and 39 abnormal). Samples were analyzed with chromosomal microarray (CMA). Study 2: Women (N = 282) who accepted cfNIPT were recruited for cbNIPT. cfNIPT was analyzed using sequencing and cbNIPT by CMA.

Results

Study 1: cbNIPT detected all aberrations (32/32) found in CVS: trisomies 13, 18 and 21 (23/23), pathogenic copy number variations (CNVs) (6/6) and sex chromosome aberrations (3/3). cbNIPT detected 3/8 cases of mosaicism in the placenta. Study 2: cbNIPT detected all trisomies found with cfNIPT (6/6) and had no false positive (0/246). One of the three CNVs called by cbNIPT was confirmed by CVS but was undetected by cfNIPT, two were false positives. cbNIPT detected mosaicism in five samples, of which two were not detected by cfNIPT. cbNIPT failed in 7.8% compared to 2.8% in cfNIPT.

Conclusion

Circulating trophoblasts in the maternal circulation provide the potential of screening for aneuploidies and pathogenic CNVs covering the entire fetal genome.  相似文献   
45.
Conservation and restoration of semi-natural wet grasslands often suffer from poor knowledge on successional pathways of respective habitats under different mowing treatments to derive profound management concepts. In this study, we present the results of a 20-year experiment in six semi-natural wet grassland sites in NW Germany including mowing with and without fertilizer addition and fallow. Succession was recorded by permanent plots. The studied wet grassland communities responded quite similar under equal management. Fallow resulted in the most significant changes in floristic and functional composition facilitating highly competitive rushes and tall forbs. The changes were more pronounced the more the experimental management treatment differed from the former use. For all mowing treatments without fertilizer application, we still observed directed changes in the floristic composition even after 20 years. In particular mowing twice led to a shift in floristic composition towards stress-tolerant plants with low nutrient demands, which was paralleled by decreasing productivity and strongly diminishing Ellenberg nutrient values. Our results documented that restoration of low-yielding target communities by regular mowing is possible – even in an area with high atmospheric nitrogen inputs. However, our results also show that succession did not come to an end even after 20 years, most obviously due to the continuous but very slow immigration and spread of new species.  相似文献   
46.
Climate change is a multi-dimensional issue and in terms of adaptation numerous state and non-state actors are involved from global to national and local scales. The aim of this paper is first to analyse specific institutional networks involved in climate change predominantly at the national level in South Africa and second to determine how different stakeholders perceive their role vis-a-vis climate change adaptation. Within the South African context there is a gap in understanding and evaluating how institutional networks operate and thus the findings of this work may help inform and strengthen such relationships in the future. Results showed that few institutions fully understand the implications of adaptation and their roles and responsibilities have not yet been properly defined. Constraints relating to capacity, lack of awareness and poor information flow need to be addressed. Climate change is perceived as an important issue although problems such as poverty reduction and job creation remain national priorities. Most importantly this research has demonstrated how adaptation challenges the hierarchical manner in which government works and a more collaborative approach to climate change adaptation is needed. Adaptation needs to be mainstreamed and institutional networks need to be strengthened in order for adaptation mechanisms to be effectively implemented.
Ingrid Christine KochEmail:
  相似文献   
47.
The differential allocation hypothesis proposes that females mated to attractive males should invest more resources in their offspring than those mated to less-attractive males, whereas the compensation hypothesis posits that females mated to less-attractive males should invest more resources in their offspring to compensate for lower-quality young. We tested these hypotheses by manipulating attractiveness of male house wrens (Troglodytes aedon) prior to female arrival by adding extra nest sites to territories of some males while leaving control males with only a single nest site. Females laid their eggs sooner in the nests of attractive males, and attractive males were more likely to retain their territory over successive broods and were marginally more likely to obtain a mate for a second brood later in the season than were control males, thereby confirming the effect of our manipulation on male attractiveness. Experimentally enhanced attractiveness also led to increased hematocrit in males. However, there were no consistent differences in the number, size, or quality of eggs laid by females mated to attractive and control males, nor were there any differences in the size, health state, or immune function of nestlings produced from these eggs. There was also no effect of treatment on the number of nestlings surviving to fledging. Collectively, these results are inconsistent with both the differential allocation hypothesis and the compensation hypothesis. Future studies should consider the possibility that the criteria used by females in selecting a mate may vary temporally and be more flexible than generally thought.  相似文献   
48.
In accordance with observations by other groups direct CVS preparations reveal only a few mitoses, whereas semi-direct cultures (overnight incubation) give good results. By monitoring the BrdU uptake with an immunological method, a delay in the proliferation activity in native villi could be observed up to 7 h after biopsy.  相似文献   
49.
A specimen of the horned dinosaur Psittacosaurus from the early Cretaceous of China is described in which the integument is extraordinarily well-preserved. Most unusual is the presence of long bristle-like structures on the proximal part of tail. We interpret these structures as cylindrical and possibly tubular epidermal structures that were anchored deeply in the skin. They might have been used in display behavior and especially if one assumes that they were colored, they may have had a signal function. At present, there is no convincing evidence which shows these structures to be homologous to the structurally different integumentary filaments of theropod dinosaurs. Independent of their homology, however, the discovery of bristle-like structures in Psittacosaurus is of great evolutionary significance since it shows that the integumentary covering of at least some dinosaurs was much more complex than has ever been previously imagined.  相似文献   
50.
The dispersion of pollutants from the huge Buncefield oil depot fire that occurred on 11 December 2005 is simulated using a regional Eulerian chemistry-transport model. We analyse the transport and mixing of the fire plume. We show that the hot plume never reached the ground. Instead, it pierced the thin wintertime boundary layer and was injected into the free troposphere at higher altitudes. This is in agreement with data from many air quality stations. This high injection was fortunate because the fine aerosol particles (PM10) mass column generated by the fire smoke exceeded that of ordinary pollution by an order of magnitude. Our regional chemistry-transport modelling is able to predict the early development of the plume dispersion, as shown by a qualitative comparison between simulated PM10 columns and a satellite image obtained by the EOS-TERRA-MODIS sensor.If the accident had occurred in summer when boundary layers are much deeper and convective, a severe degradation in air quality due to PM10 could have occurred, as shown by a sensitivity simulation assuming a similar fire during one of the hottest days of August 2003. The modelled impact of the fire on regional and European air quality levels strongly depends on the altitude reached by the buoyant plume, as shown by a set of sensitivity simulations with variable injection heights. However, in all cases we found that the fire only affected surface aerosol concentrations without increasing photochemical pollution.  相似文献   
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