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1.
本研究的目标是增加关于模型生成数据被用作水质管理的交流工具时,地方利益相关者接受该数据的知识.研究地区选在瑞典西南部的伦讷(R(o)nne(a))河流域.结果表明,模型生成数据起到了联合因素的作用.同时,利益相关者与提供的数据有关,主要问题为未考虑到的污染源、测定污染时缺乏信任、自然变化和延迟效应的影响的不确定性.确定了4组影响利益相关者接受模型生成数据的因素对其实际应用的信心,对所涉及的参与人员或对话资料提供者(如专家、决策者、媒体)的信心,参与者的社会特征(如年龄和职业),和数据的交流方式(如交流的语气、小组的构成、持续时间、对话的地理尺度).对给定的模型生成数据实际应用的公平性的感知,也是接受与否的一个重要因素.  相似文献   
2.

Objective

Omphalocele is known to be associated with genetic anomalies like trisomy 13, 18 and Beckwith–Wiedemann syndrome, but not with Turner syndrome (TS). Our aim was to assess the incidence of omphalocele in fetuses with TS, the phenotype of this association with other anomalies, their karyotype, and the fetal outcomes.

Method

Retrospective multicenter study of fetuses with confirmed diagnosis of TS. Data were extracted from a detailed questionnaire sent to specialists in prenatal ultrasound.

Results

680 fetuses with TS were included in this analysis. Incidence of small omphalocele in fetuses diagnosed ≥12 weeks was 3.1%. Including fetuses diagnosed before 12 weeks, it was 5.1%. 97.1% (34/35) of the affected fetuses had one or more associated anomalies including increased nuchal translucency (≥3 mm) and/or cystic hygroma (94.3%), hydrops/skin edema (71.1%), and cardiac anomalies (40%). The karyotype was 45,X in all fetuses. Fetal outcomes were poor with only 1 fetus born alive.

Conclusion

TS with 45,X karyotype but not with X chromosome variants is associated with small omphalocele. Most of these fetuses have associated anomalies and a poor prognosis. Our data suggest an association of TS with omphalocele, which is evident from the first trimester.  相似文献   
3.
4.
Copulation in the simultaneous hermaphrodite Siphopteron sp. involves injection of prostate fluids into the mating partner with a stylet-shaped penile appendage before insemination. It has been hypothesised that such traumatic secretion transfer manipulates sex roles or the recipient’s short-term reproductive output. To test manipulative effects of traumatic secretion transfer, we ablated the stylet of male-acting individuals and then paired them to untreated focal individuals. Mating behaviour and egg output of focal individuals was then compared between this ‘no injection group’ and a ‘control group’ with sham-treated mating partners. We found that penile stylets were inserted at different areas prior to and during insemination, but prostate fluid injection was restricted to the first phase. Here, injections were into the anterior foot region, indicating that prostate secretions target the nearby male or female copulatory tracts. Our experimental manipulation of traumatic secretion transfer did not affect the exhibited mating roles. Matings in both treatments were usually reciprocal so that both partners acted in the male as well as female mating role. Moreover, sperm recipient reproductive output did not differ between treatments. We conclude that traumatic secretion transfer in this species either affects currently unmeasured traits, for instance the donor’s paternity share, or that these sea slugs are so well-adapted to traumatic secretion transfer that the effects were too subtle to be detected in our current assays.  相似文献   
5.
In social hymenoptera, the reproductive division of labor is often linked to differences in individual body size with the reproductive caste (the queen) being larger than the workers. Likewise, the reproductive potential may vary with size within the worker caste and could affect the evolution of worker size in social insects. Here, we tested the relationship between worker size and reproductive potential in the facultative parthenogenetic ant Cataglyphis cursor. Colonies are headed by a multiply mated queen, but workers can produce gynes (virgin queens) and workers by thelytokous parthenogenesis after the queen's death. We observed the behaviour of workers (n = 357) until the production of gynes (212 h over 3 months) in an orphaned colony (mated queen not present). The size of workers was measured, and their paternal lineage determined using six microsatellite markers, to control for an effect of patriline. Larger workers were more likely to reproduce and lay more eggs indicating that individual level selection could take place. However, paternal lineage had no effect on the reproductive potential and worker size. From the behavioural and genetic data, we also show for the first time in this species, evidence of aggressive interactions among workers and a potential for nepotism to occur in orphaned colonies, as the five gynes produced belonged to a single paternal lineage.  相似文献   
6.
The CA Department of Pesticide Regulation (CDPR) developed methods to select pesticides and a community to fulfill criteria for an ambient air monitoring study it conducted as part of the CA Environmental Protection Agency's Environmental Justice Action Plan. Using a scoring system, CDPR evaluated 100 pesticides based on statewide-reported pesticide use, volatility, and priority in CDPR's risk assessment process (indicators of exposure and toxicity) to produce a list of pesticides to consider as candidates for monitoring. The CDPR also evaluated and scored 83 communities based on demographics and health factors, availability of cumulative impacts data, and reported pesticide use to create a list of community candidates. The scores provide relative rankings to distinguish more highly impacted communities from less impacted ones and to identify which pesticides might contribute most to potential adverse health effects. These methods use criteria that can be quantified, validated, and verified in order to provide a transparent and fair selection process. Based on public comments and highest scores, CDPR recommended 40 pesticides (including some of their degradation products) and one community for its yearlong monitoring study. The CDPR then further refined its list of pesticides by soliciting input from local and technical advisory groups. The CDPR plans to use these methods to select pesticides and communities in future monitoring activities.  相似文献   
7.
Ion-exchange resins (IER) offer alternative approaches to measuring ionic movement in soils that may have advantages over traditional approaches in some settings, but more information is needed to understand how IER compare with traditional methods of measurement in forested ecosystems. At the Bear Brook Watershed in Maine (BBWM), one of two paired, forested watersheds is treated bi-monthly with S and N (28.8 and 25.2kgha−1yr−1 of S and N, respectively). Both IER and ceramic cup tension lysimeters were used to study soil solution responses after ∼11 years of treatment. Results from both methods showed treatments resulted in the mobilization of base cations and Al, and higher SO4—S and inorganic N in the treated watershed. Both methods indicated similar differences in results associated with forest type (hardwoods versus softwoods), a result of differences in litter quality and atmospheric aerosol interception capacity. The correlation between lysimeter and IER data for individual analytes varied greatly. Significant correlations were evident for Na (r=0.75), Al (r=0.65), Mn (r=0.61), Fe (r=0.57), Ca (r=0.49), K (r=0.41) and NO3—N (r=0.59). No correlation was evident between IER and soil solution data for NH4—N and Pb. Both IER and soil solution techniques suggested similar interpretations of biogeochemical behavior in the watershed.  相似文献   
8.
The structure of the habitat is usually crucial for growth and survival of young life stages. Presently, some nursery areas of fish larvae are changing due to eutrophication, e.g. due to enhanced growth of ephemeral filamentous algae at the expense of perennial species. We studied the influence of two habitats, one with filamentous algae (Cladophora glomerata) and the other with bladder wrack (Fucus vesiculosus), on habitat choice of pike larvae (Esox lucius) in the absence/presence of a predator or a competitor. We further tested whether the habitat choice is adaptive in increasing survival under predation threat. In contrast to expectations, pike larvae preferred the habitat with ephemeral filamentous algae to the bladder wrack, thriving in clean waters, independent of the presence/absence of both predator/competitor. In addition, the survival of the larvae was higher in the filamentous algae in the presence of predators, which suggested that the habitat preference of the larvae was adaptive. The structure of the bladderwrack habitat was probably too open for newly hatched larvae, which implies that F. vesiculosus and other large brown algae are not as important refuges for young larvae as previously thought.  相似文献   
9.

The aim of this study was to determine the bioavailability of metals in field soils contaminated with chromated copper arsenate (CCA) mixtures. The uptake and elimination kinetics of chromium, copper, and arsenic were assessed in the earthworm Eisenia andrei exposed to soils from a gradient of CCA wood preservative contamination near Hartola, Finland. In soils contaminated with 1480–1590 mg Cr/kg dry soil, 642–791 mg Cu/kg dry soil, and 850–2810 mg Ag/kg dry soil, uptake and elimination kinetics patterns were similar for Cr and Cu. Both metals were rapidly taken up and rapidly excreted by Eisenia andrei with equilibrium reached within 1 day. The metalloid As, however, showed very slow uptake and elimination in the earthworms and body concentrations did not reach equilibrium within 21 days. Bioaccumulation factors (BAF) were low for Cu and Cr (< 0.1), but high for As at 0.54–1.8. The potential risk of CCA exposure for the terrestrial ecosystem therefore is mainly due to As.

  相似文献   
10.
In Finland about 70,000 people are annually injured in pedestrian and bicycle falling accidents occurred at the street, walkways and courtyards. Around 2/3 of these occur when the walking surface is covered by ice or snow. In general, slipping is caused by both environmental and human factors. The primary environmental factor behind slipping accidents is slip resistance characteristics of underfoot surface. Especially in winter slipping accidents are mainly due to inadequate friction between footwear and underfoot surfaces. Portable devices measuring friction, i.e. slipmeters, may be used for assessing slipperiness on different walking surfaces in situ. During winter seasons 2003 and 2004 a study was performed to evaluate the usability of portable slip simulator for measuring slipperiness of walkways on varying weather conditions and to assess slip resistance of different footwear. The Portable Slip Simulator proved to be applicable for measuring in situ the slipperiness of wintry walking surfaces and evaluating quality of winter maintenance. Significant differences in traction between footwear were found especially in normal Finnish climate winter days when friction provided by slip-resistant footwear was multifold compared to a poorer one. On very slippery icy surfaces no footwear provided enough grip and, therefore, in such conditions anti-slip devices should be used.  相似文献   
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