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401.
Longitudinal sampling of four cohorts of Neopomacentrus filamentosus, a common tropical damselfish from Dampier Archipelago, Western Australia, revealed the evolution of size structure after settlement. Light traps collected premetamorphic individuals from the water column ("settlers") to establish a baseline for each cohort. Subsequently, divers collected benthic juveniles ("recruits") at 1-3-month intervals to determine the relative impacts of post-settlement mortality during the first three months. Growth trajectories for individual fish were back-calculated from otolith records and compared with nonlinear mixed-effects models. Size-selective mortality was detected in all cohorts with the loss of smaller, slower growing individuals. Three months after settlement, recruits showed significantly faster growth as juveniles, faster growth as larvae, and larger sizes as hatchlings. The timing and intensity of post-settlement selection differed among cohorts and was correlated with density at settlement. The cohort with the greatest initial abundance experienced the strongest selective mortality, with most of this mortality occurring between one and two months after settlement when juveniles began foraging at higher positions in the water column. Significant genetic structure was found between settlers and three-month-old recruits in this cohort as a result of natural selection that changed the frequency of mtDNA haplotypes measured at the control region. The extent of this genetic difference was enlarged or reduced by artificially manipulating the intensity of size-based selection, thus establishing a link between phenotype and haplotype. Sequence variation in the control region of the mitochondrial genome has been linked to mitochondrial efficiency and weight gain in other studies, which provides a plausible explanation for the patterns observed here.  相似文献   
402.
Objective: Understanding pedestrian injury trends at the local level is essential for program planning and allocation of funds for urban planning and improvement. Because we hypothesize that local injury trends differ from national trends in significant and meaningful ways, we investigated citywide pedestrian injury trends to assess injury risk among nationally identified risk groups, as well as identify risk groups and locations specific to Baltimore City.

Methods: Pedestrian injury data, obtained from the Baltimore City Fire Department, were gathered through emergency medical services (EMS) records collected from January 1 to December 31, 2014. Locations of pedestrian injuries were geocoded and mapped. Pearson's chi-square test of independence was used to investigate differences in injury severity level across risk groups. Pedestrian injury rates by age group, gender, and race were compared to national rates.

Results: A total of 699 pedestrians were involved in motor vehicle crashes in 2014—an average of 2 EMS transports each day. The distribution of injuries throughout the city did not coincide with population or income distributions, indicating that there was not a consistent correlation between areas of concentrated population or concentrated poverty and areas of concentrated pedestrian injury. Twenty percent (n = 138) of all injuries occurred among children age ≤14, and 22% (n = 73) of severe injuries occurred among young children. The rate of injury in this age group was 5 times the national rate (Incident Rate Ratio [IRR] = 4.81, 95% confidence interval [CI], [4.05, 5.71]). Injury rates for adults ≥65 were less than the national average.

Conclusions: As the urban landscape and associated pedestrian behavior transform, continued investigation of local pedestrian injury trends and evolving public health prevention strategies is necessary to ensure pedestrian safety.  相似文献   

403.
Wildfire may be the clearest example to date of a socio-natural hazard that is being exacerbated by climate change, making wildfire an essential lens through which to investigate learning and adaptation in the Anthropocene. Here, we study discourse about simultaneous and recurring catastrophic wildfires in Colorado newspapers. We find that the wildfires’ anniversaries served as opportunities for critical reflection on hazard causality and mitigation in local media, particularly the first anniversary and especially for a community that experienced two catastrophic wildfires in a row. Two mediated prospective memory practices—invoking hindsight as foresight and recognizing a new normal—contributed to this discourse. However, learning and adaptation discourse faded in local media at later anniversaries. These findings contribute to learning and adaptation scholarship by connecting the concept of mediated prospective memory to disaster-related media studies and attending to the intricacies of anniversary commemoration under circumstances of simultaneous and recurring disasters.  相似文献   
404.
The focus on climate change adaptation, rather than mitigation, has become more prominent since the turn of the century. Given this, it is important to consider what has been achieved so far, particularly community-based approaches which have become the resolve for practitioners and donor agencies working in the sector. This review of 128 publications on community-based climate change adaptation, identified through a systematic database search, follows the development of this body of work in the academic literature. Commencing in the early 2000s, the literature detailed the emergence of community-based adaptation (CBA), driven by a number of factors: recognition of the human dimensions of changes; appreciation of the role of local knowledge for strengthening adaptive capacity; and a push to focus on the scale at which impacts are felt and link this action with pro-poor development outcomes. A more substantial body of work emerged in the literature from 2010 onwards, defining a series of key enablers for effective CBA, which included: use participatory approaches; recognise that adaptation is a social process; and support CBA at multiple scales. More recently, there has been a growing emphasis in the literature to re-conceptualise CBA, which will require focusing on innovation, learning and multi-sectoral approaches.  相似文献   
405.
Ambient concentrations of PM2.5 and PM10 are of concern with respect to effects on human health and environment. Increased levels of mortality and morbidity have been associated with respirable particulate air pollution. In India, it is not yet mandatory to monitor PM2.5 levels therefore very limited information is available on PM2.5 levels. To understand the fine particle pollution and also correlate with PM10 which are monitored regularly in compliance with ambient air quality standards. This study was carried out to monitor PM2.5, PM10, and NO2 for about one year in a residential cum commercial area of Mumbai city with a view to understand their correlation. The average PM2.5 concentration at ambient and Kerbsite was 43 and 69 μg/m3. The correlation coefficients between PM2.5 and PM10 at ambient and Kerbsite were 0.83 and 0.85 respectively thus indicating that most of the PM2.5 and PM10 are from similar sources. TSP, PM10 levels exceeded Central Pollution Control Board(CPCB) standard during winter season. PM2.5 levels also exceeded 24 hourly average USEPA standard during winter season indicating unhealthy air quality.  相似文献   
406.
Strategic land retirement in agricultural settings has been used as one way to achieve a combination of social objectives, which include ameliorating water quality problems and enhancing existing systems of wildlife habitat. This study uses a simulation model operating on a virtual landscape, along with the compromise programming method, to illustrate the implications of alternative weighting schemes for the long-term performance of the landscape toward various objectives. The analysis suggests that particular spatial patterns may be related to how various objectives are weighted. The analysis also illustrates the inevitable trade-offs among objectives, although it may be tempting to present retirement strategies as “win-win.”  相似文献   
407.
The structure and ultrastructure of the photoreceptors of several life history stages of the ontogenetically migrating lophogastrid crustacean Gnathophausia ingens were examined. The younger instars of this species live in a much brighter light field than the older instars, and this difference is reflected in differences in their visual systems. The shallowest free living individuals (instars 3 and 4) possess a superposition eye with almost no clear zone, which minimizes the light shared between ommatidia and reduces the sensitivity of the eye. A progression to superposition optics with a large clear zone, usually associated with night-active or deep-living species, occurs as the animals move deeper in the water column. Regional differences within the eye are also evident, with a largely nonexistent clear zone in the dorsal region and a large clear zone in the ventral region in the eyes of instar 5 animals, the first instar to move to deeper depths. The deepest living instars (10–12) possess superposition optics with a large clear zone throughout the eye, and are significantly more sensitive to light than the younger, shallower instars.  相似文献   
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ABSTRACT: Many coastal states are facing increasing urban growth along their coast lines. The growth has caused urban non-point source nitrogen runoff to be a major contributor to coastal and estuarine enrichment. Water resource managers are responsible for evaluating the impacts from point and non-point sources in developed watersheds and developing strategies to manage future growth. Non-point source models provide an effective approach to these management challenges. The Agricultural Non-Point Source Model (AGNPS) permits the incorporation of important spatial information (soils, landuse, topography, hydrology) in simulating surface hydrology and nitrogen non-point source runoff. The AGNPS model was adapted for developed coastal watersheds by deriving urban coefficients that reflect urban landuse classes and the amount of impervious surface area. Popperdam Creek watershed was used for model parameter development and model calibration. Four additional watersheds were simulated to validate the model. The model predictions of the peak flow and total nitrogen concentrations were close to the field measurements for the five sub-basins simulated. Measured peak flow varied by 30 fold among the sub-basins. The average simulated peak flow was within 14 percent of the average measured peak flow. Measured total nitrogen loads varied over an order of magnitude among the sub-basins yet error between the measured and simulated loads for a given sub-basin averaged 5 percent. The AGNPS model provided better estimates of nitrogen loads than widely used regression methods. The spatial distribution of important watershed characteristics influenced the impacts of urban landuse and projecting future residential expansion on runoff, sediment and nitrogen yields. The AGNPS model provides a useful tool to incorporate these characteristics, evaluate their importance, and evaluate fieldscale to watershed-scale urban impacts.  相似文献   
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