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71.
Interactions between period and degree of pressure have been investigated in membrane and filament systems of gill tissue, skin, and muscles of Modiolus modiolus, Mytilus edulis (Baltic and North Seas) and Branchiostoma lanceolatum (Pallas) at the ultrastructural level. The results show the importance of time for the degree of structural disintegration at constant pressure. Destruction already occurs after 2 min of low-pressure treatment at 300 atm. After 10 min continued pressure at the same level, no further structural dis-organization (qualitative or quantitative) occurs, even when the time period is prolonged. For some organelles (i.e., cilia and microvilli), better structural preservation is apparent after 30-min pressure compared to 10-min treatment at the same pressure level. This is a so-called “acclimatisation” to pressure.  相似文献   
72.
Selective catalytic reduction (SCR) technology increasingly is being applied for controlling emissions of nitrogen oxides (NOx) from coal-fired boilers. Some recent field and pilot studies suggest that the operation of SCR could affect the chemical form of mercury (Hg) in coal combustion flue gases. The speciation of Hg is an important factor influencing the control and environmental fate of Hg emissions from coal combustion. The vanadium and titanium oxides, used commonly in the vanadia-titania SCR catalyst for catalytic NOx reduction, promote the formation of oxidized mercury (Hg2+). The work reported in this paper focuses on the impact of SCR on elemental mercury (Hg0) oxidation. Bench-scale experiments were conducted to investigate Hg0 oxidation in the presence of simulated coal combustion flue gases and under SCR reaction conditions. Flue gas mixtures with different concentrations of hydrogen chloride (HCl) and sulfur dioxide (SO2) for simulating the combustion of bituminous coals and subbituminous coals were tested in these experiments. The effects of HCl and SO2 in the flue gases on Hg0 oxidation under SCR reaction conditions were studied. It was observed that HCl is the most critical flue gas component that causes conversion of Hg0 to Hg2+ under SCR reaction conditions. The importance of HCl for Hg0 oxidation found in the present study provides the scientific basis for the apparent coal-type dependence observed for Hg0 oxidation occurring across the SCR reactors in the field.  相似文献   
73.
Adger WN  Kelly PM  Winkels A  Huy LQ  Locke C 《Ambio》2002,31(4):358-366
We argue that all aspects of demographic change, including migration, impact on the social resilience of individuals and communities, as well as on the sustainability of the underlying resource base. Social resilience is the ability to cope with and adapt to environmental and social change mediated through appropriate institutions. We investigate one aspect of the relationship between demographic change, social resilience, and sustainable development in contemporary coastal Vietnam: the effects of migration and remittances on resource-dependent communities in population source areas. We find, using longitudinal data on livelihood sources, that emigration and remittances have offsetting effects on resilience within an evolving social and political context. Emigration is occurring concurrently with, not driving, the expansion of unsustainable coastal aquaculture. Increasing economic inequality also undermines social resilience. At the same time diversification and increasing income levels are beneficial for resilience.  相似文献   
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Carry-over effects refer to processes that occur in one season and influence fitness in the following. In birds, two costly activities, namely reproduction and moult, are restricted to a small time window, and sometimes overlap. Thus, colour in newly moulted feathers is likely to be affected by the costs of reproduction. Using models of bird vision we investigated male colour change in a free-living population of blue tits (Cyanistes caeruleus) in three sampling occasions: spring 1, winter and spring 2. We related crown, tail, breast and cheek feather colouration after the moult (winter) to the intensity of infections by blood parasites during reproduction (spring 1). In the following spring (spring 2), we explored mating patterns with respect to changes in feather colour (springs 1 vs. 2). Males that were less intensely infected by the malaria parasite Plasmodium while breeding showed purer white cheek feathers in winter, which may indicate higher feather quality. Increased brightness in the white cheek was associated with better body condition during reproduction. In the following season, males with brighter cheeks paired with females that had noticeably brighter cheek patches compared to the male’s previous mate. These results suggest that the conditions experienced during reproduction are likely to affect moult and thus feather colouration, at least in the white patch. High quality individuals may allocate resources efficiently during reproduction increasing future reproductive success through variation in mating patterns. Carry-over effects from reproduction might extend not only to the non-breeding phase, but also to the following breeding season.  相似文献   
77.
Objective: Road traffic mortality takes an enormous toll in every society. Transport safety interventions play a crucial role in improving the situation. In the period 1996–2014 several road safety measures, including a complex new road traffic law in 2009, were implemented in the Slovak Republic, introducing stricter conditions for road users.

The aim of this study is to describe and analyze the trends in road user mortality in the Slovak Republic in individual age groups by sex during the study period 1996–2014.

Methods: Data on overall mortality in the Slovak Republic for the period 1996–2014 were obtained from the Statistical Office of the Slovak Republic. Mortality rates were age-adjusted to the European standard population. Joinpoint regression was used to assess the statistical significance of change in time trends of calculated standardized mortality rates.

Results: Mortality rates of all types of road users as well as all age groups and both sexes in the Slovak Republic in the period 1996–2014 are decreasing. The male : female ratio decreased from 4:1 in 1996 to 2:1 in 2014. Motor vehicle users (other than motorcyclists) and pedestrians have the highest mortality rates among road user groups. Both of these groups show a significant decline in mortality rates over the study period. Within the age groups, people age 65 years and over have the highest mortality rates, followed by the age groups 25–64 and 15–24 years old.

Joinpoint regression confirmed a steady, significant decline in all mortality rates over the study period. A statistically significant decrease in mortality rates in the last years of the study period was observed in the age group 25–64 and in male motorcycle users.

Assessing the impact of the 2009 road traffic law, a drop was observed in the average standardized mortality rate of all road traffic users from 14.56 per 100,000 person years in the period 1996–2008 to 7.69 per 100,000 person years in the period 2009–2014. A similar drop in the average standardized mortality rate was observed in all individual road user groups.

Conclusions: The implementation of the new traffic regulations may have contributed significantly to the observed decrease in mortality rates of road users in the Slovak Republic. A significant decrease in mortality was observed in all population groups and in all groups of road users. The introduction of a new comprehensive road traffic law may have expedited the decrease of road fatalities, especially in the age group 25–64 years old. This type of evidence-based epidemiology data can be used for improved targeting of future public health measures for road traffic injury prevention.  相似文献   

78.
Poaching can have devastating impacts on animal and plant numbers, and in many countries has reached crisis levels, with illegal hunters employing increasingly sophisticated techniques. We used data from an 8‐year study in Savé Valley Conservancy, Zimbabwe, to show how geographic profiling—a mathematical technique originally developed in criminology and recently applied to animal foraging and epidemiology—can be adapted for use in investigations of wildlife crime. The data set contained information on over 10,000 incidents of illegal hunting and the deaths of 6,454 wild animals. We used a subset of data for which the illegal hunters’ identities were known. Our model identified the illegal hunters’ home villages based on the spatial locations of the hunting incidences (e.g., snares). Identification of the villages was improved by manipulating the probability surface inside the conservancy to reflect the fact that although the illegal hunters mostly live outside the conservancy, the majority of hunting occurs inside the conservancy (in criminology terms, commuter crime). These results combined with rigorous simulations showed for the first time how geographic profiling can be combined with GIS data and applied to situations with more complex spatial patterns, for example, where landscape heterogeneity means some parts of the study area are less likely to be used (e.g., aquatic areas for terrestrial animals) or where landscape permeability differs (e.g., forest bats tend not to fly over open areas). More broadly, these results show how geographic profiling can be used to target antipoaching interventions more effectively and more efficiently and to develop management strategies and conservation plans in a range of conservation scenarios.  相似文献   
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Objective

The purpose of this study was to explore the diagnostic yield and clinical utility of trio-based rapid whole exome sequencing (rWES) in pregnancies of fetuses with a wide range of congenital anomalies detected by ultrasound imaging.

Methods

In this observational study, we analyzed the first 54 cases referred to our laboratory for prenatal rWES to support clinical decision making, after the sonographic detection of fetal congenital anomalies. The most common identified congenital anomalies were skeletal dysplasia (n = 20), multiple major fetal congenital anomalies (n = 17) and intracerebral structural anomalies (n = 7).

Results

A conclusive diagnosis was identified in 18 of the 54 cases (33%). Pathogenic variants were detected most often in fetuses with skeletal dysplasia (n = 11) followed by fetuses with multiple major fetal congenital anomalies (n = 4) and intracerebral structural anomalies (n = 3). A survey, completed by the physicians for 37 of 54 cases, indicated that the rWES results impacted clinical decision making in 68% of cases.

Conclusions

These results suggest that rWES improves prenatal diagnosis of fetuses with congenital anomalies, and has an important impact on prenatal and peripartum parental and clinical decision making.  相似文献   
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