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1.
Climate change poses water resource challenges for many already water stressed watersheds throughout the world. One such watershed is the Upper Neuse Watershed in North Carolina, which serves as a water source for the large and growing Research Triangle Park region. The aim of this study was to quantify possible changes in the watershed’s water balance due to climate change. To do this, we used the Soil and Water Assessment Tool (SWAT) model forced with different climate scenarios for baseline, mid‐century, and end‐century time periods using five different downscaled General Circulation Models. Before running these scenarios, the SWAT model was calibrated and validated using daily streamflow records within the watershed. The study results suggest that, even under a mitigation scenario, precipitation will increase by 7.7% from the baseline to mid‐century time period and by 9.8% between the baseline and end‐century time period. Over the same periods, evapotranspiration (ET) would decrease by 5.5 and 7.6%, water yield would increase by 25.1% and 33.2%, and soil water would increase by 1.4% and 1.9%. Perhaps most importantly, the model results show, under a high emission scenario, large seasonal differences with ET estimated to decrease by up to 42% and water yield to increase by up to 157% in late summer and fall. Planning for the wetter predicted future and corresponding seasonal changes will be critical for mitigating the impacts of climate change on water resources.  相似文献   
2.
Visibility degradation, one of the most noticeable indicators of poor air quality, can occur despite relatively low levels of particulate matter when the risk to human health is low. The availability of timely and reliable visibility forecasts can provide a more comprehensive understanding of the anticipated air quality conditions to better inform local jurisdictions and the public. This paper describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada’s operational Regional Air Quality Deterministic Prediction System (RAQDPS) for the Lower Fraser Valley of British Columbia. A baseline model (GM-IMPROVE) was constructed using the revised IMPROVE algorithm based on unprocessed forecasts from the RAQDPS. Three additional prototypes (UMOS-HYB, GM-MLR, GM-RF) were also developed and assessed for forecast performance of up to 48 hr lead time during various air quality and meteorological conditions. Forecast performance was assessed by examining their ability to provide both numerical and categorical forecasts in the form of 1-hr total extinction and Visual Air Quality Ratings (VAQR), respectively. While GM-IMPROVE generally overestimated extinction more than twofold, it had skill in forecasting the relative species contribution to visibility impairment, including ammonium sulfate and ammonium nitrate. Both statistical prototypes, GM-MLR and GM-RF, performed well in forecasting 1-hr extinction during daylight hours, with correlation coefficients (R) ranging from 0.59 to 0.77. UMOS-HYB, a prototype based on postprocessed air quality forecasts without additional statistical modeling, provided reasonable forecasts during most daylight hours. In terms of categorical forecasts, the best prototype was approximately 75 to 87% correct, when forecasting for a condensed three-category VAQR. A case study, focusing on a poor visual air quality yet low Air Quality Health Index episode, illustrated that the statistical prototypes were able to provide timely and skillful visibility forecasts with lead time up to 48 hr.

Implications: This study describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada’s operational Regional Air Quality Deterministic Prediction System. The main applications include tourism and recreation planning, input into air quality management programs, and educational outreach. Visibility forecasts, when supplemented with the existing air quality and health based forecasts, can assist jurisdictions to anticipate the visual air quality impacts as perceived by the public, which can potentially assist in formulating the appropriate air quality bulletins and recommendations.  相似文献   

3.

Community-based approaches are pursued in recognition of the need for place-based responses to environmental change that integrate local understandings of risk and vulnerability. Yet the potential for fair adaptation is intimately linked to how variations in perceptions of environmental change and risk are treated. There is, however, little empirical evidence of the extent and nature of variations in risk perception in and between multiple community settings. Here, we rely on data from 231 semi-structured interviews conducted in nine communities in Western Province, Solomon Islands, to statistically model different perceptions of risk and change within and between communities. Overall, people were found to be less likely to perceive environmental changes in the marine environment than they were for terrestrial systems. The distance to the nearest market town (which may be a proxy for exposure to commercial logging and degree of involvement with the market economy), and gender had the greatest overall statistical effects on perceptions of risk. Yet, we also find that significant environmental change is underreported in communities, while variations in perception are not always easily related to commonly assumed fault lines of vulnerability. The findings suggest that there is an urgent need for methods that engage with the drivers of perceptions as part of community-based approaches. In particular, it is important to explicitly account for place, complexity and diversity of environmental risk perceptions, and we reinforce calls to engage seriously with underlying questions of power, culture, identity and practice that influence adaptive capacity and risk perception.

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5.
Exencephaly was diagnosed at 17 weeks in a 27-year-old primigravida with abnormalities of the hands and a family history suggestive of autosomal dominant brachydactyly and clinodactyly. In this family there was also a history of ‘anencephaly’. To our knowledge, this is the first report on the association of exencephaly and autosomal dominant brachydactyly. As the relationship between hand and cranial anomalies is well established, we suggest that this association in our case could be due to a defect in the same gene.  相似文献   
6.
The fetal gall bladder can now be easily identified during the second and third trimesters using high-resolution ultrasonography. In this report we present eight fetuses with an enlarged gall bladder detected on prenatal ultrasonography at a mean gestational age of 24.6 weeks (range 19–31 weeks). Additional ultrasonographic findings were present in four cases: fetal anomalies and intrauterine growth retardation in three and polyhydramnios in one. Of those cases associated with fetal anomalies, one woman underwent amniocentesis at 21 weeks revealing trisomy 18. The other two declined prenatal karyotyping; neonatal karyotyping revealed trisomy 13 in one and trisomy 18 in the other. Although an enlarged fetal gall bladder can be a normal variant in the second and third trimesters, the prenatal detection of cholecystomegaly should prompt a search for associated anomalies and other markers of aneuploidy. If found, prenatal karyotyping should be considered.  相似文献   
7.
The invertebrate neuromodulator octopamine is known to be involved in bees' associative learning, enhancing the responsiveness of a bee to a conditioned stimulus. In this study, we tested the effect of octopamine on the choice behavior of free-flying bumblebees using a two-phase experiment in an array of artificial flowers. During the first phase of the experiment, the bee was allowed to collect octopamine-laden sugar water from two types of equally rewarding flowers (yellow versus blue). In the second phase, one type of flower was set to be unrewarding. The behavior of the bee (proportion of visits to the unrewarding flowers) over the two phases was fitted to a sigmoid regression model. Our results show that octopamine had no significant effect on the bees' equilibrium choice or on the overall rate of the behavioral change in response to the change in reward. Rather, octopamine significantly affected the time interval between the change in reward status and the initiation of behavioral change in the bee.  相似文献   
8.
Twelve second-trimester fetuses with cystic hygroma underwent fetal blood sampling for rapid karyotyping, haematologic evaluation, and blood gas analysis. An abnormal karyotype was found in seven cases: monosomy X in five, trisomy 21 in one, and trisomy 13 in the other. Eight often fetuses undergoing blood gas analysis showed hypoxaemia, five of which were growth-retarded. Nine pregnancies were terminated. Of the remaining three, only one fetus survived the perinatal period.  相似文献   
9.
A technique is described for measuring pressure within the amniotic cavity and within fetal vessels and/or body compartments. Two saline-filled catheters were connected at one end to needles inserted during indicated invasive procedures and at the other to silicon strain gauge transducers. In 36 pregnancies with normal liquor volume, stable intra-amniotic pressure (IAP, range 1–14 mmHg) increased with gestation (r=0·48, p<0·01). In pregnancies complicated by severe oligohydramnios, IAP was ≤ 1 mm Hg and rose to normal levels with saline amnioinfusion. Raised IAP (range 17–26 mm Hg), found in pregnancies with gross polyhydramnios, fell with drainage of amniotic fluid. Subtraction manometry was used to determine supra-amniotic pressure within the intervillus space, umbilical vein, umbilical artery, abdominal and thoracic cavities, and the urinary tract in normal and/or pathological fetuses. Low intravesical and intrapelvicalyceal pressures (median 6·5, range 2–10 mmHg) were noted in fetuses with obstructive uropathies. Intrauterine subtraction manometry appears to be a useful tool in the understanding of fetal pathophysiology and may be of clinical benefit in the therapeutic drainage and infusion of amniotic fluid and in the assessment of certain fetal disease states.  相似文献   
10.
ABSTRACT: Most watershed water quality simulation models require the user to specify pollutant buildup and washoff rate parameters for pollutants, by land use. Buildup and washoff rates are difficult to measure directly, and only limited guidance and few observed data are available from the literature. Many studies, however, report storm event mean concentrations (EMCs). These EMCs must arise as a result of the buildup and washoff processes, but typically represent the net contribution from a variety of pervious and impervious surfaces. This paper explores the relationship between EMCs and buildup/washoff parameters. An assumption of the mathematical form of the buildup/washoff relationship gives an algebraic expression for the EMC consistent with model assumptions. This yields techniques to separate observed EMCs into contributions from different land uses and from pervious and impervious surfaces. Given this relationship, numerical optimization may be used to estimate site specific values of buildup and washoff parameters from observed storm EMCs for use in modeling. Use of this approach helps ensure that model parameters are consistent with observed data, providing a rational starting point for final model calibration. Several site examples demonstrate use of the method.  相似文献   
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