Routine surveillance of a large geographic region for clusters of adverse health events, particularly cancers, often involves
small area health data, possibly controlling for exposure information. Many different methods have been proposed to test for
the presence of geographical clusters. Two of the most popular methods are the spatial scan method proposed by Kulldorff and
that using a fixed number of cases within scanning circles proposed by Besag and Newell. Although the second test is very
popular, it has some difficulties. While the scan test controls for the multiple testing problem, the Besag and Newell test
does not. Additionally, the latter method requires the setting of several tuning parameters whose values affect the test performance
and are subjectively chosen by the user. This creates a difficulty to make a fair comparison between the two methods and it
explains why there have been few formal studies evaluating their relative performances. In this paper, we modify the Besag
and Newell test allowing for the control of the error type I probability and compare its power with respect to that of the
spatial scan test. We used data sets from a publicly available simulated benchmark. We found that the two methods have similar
results, except for clusters located in sparsely populated regions, where the spatial scan method presented a better performance. 相似文献
Wet deposition and related rainwater chemistry were studied at the Itatiaia massif, on which is settled the Itatiaia National Park (INP). Samples were simultaneously collected on a weekly basis over 12 months, using automated wet and dry samplers, at the INP-Headquarters (INP-Hq; altitude=820 m) and the Itatiaia Plateau (It-Pt; altitude=2460 m). Conductivity, pH, Na(+), K(+), Mg(2+), Ca(2+), NH(4)(+), Cl(-), NO(3)(-) and SO(4)(2-) were determined in 36 rainwater samples. Volume-weighted mean (VWM) pH was lower at the INP-Hq (4.9) than at the It-Pt (5.3). Very strong correlation between Cl(-) and Na(+) was found for the INP-Hq (r=0.99). At the Itatiaia massif, SO(4)(2-), NO(3)(-), and NH(4)(+) comprised together about 60% of the total inorganic ions and appear to exert the major control on rainwater pH. 相似文献
Fetal echocardiography was performed during the third trimester in a normal primigravida. The fetal heart was severely affected with the typical cardiac manifestations of Marfan syndrome. The medical history of the father was investigated and a mild form of the syndrome was diagnosed. The neonate died at 2 months of age of congestive heart failure. 相似文献
The National Weather Service (NWS) forecasts floods at approximately 3,600 locations across the United States (U.S.). However, the river network, as defined by the 1:100,000 scale National Hydrography Dataset‐Plus (NHDPlus) dataset, consists of 2.7 million river segments. Through the National Flood Interoperability Experiment, a continental scale streamflow simulation and forecast system was implemented and continuously operated through the summer of 2015. This system leveraged the WRF‐Hydro framework, initialized on a 3‐km grid, the Routing Application for the Parallel Computation of Discharge river routing model, operating on the NHDPlus, and real‐time atmospheric forcing to continuously forecast streamflow. Although this system produced forecasts, this paper presents a study of the three‐month nowcast to demonstrate the capacity to seamlessly predict reach scale streamflow at the continental scale. In addition, this paper evaluates the impact of reservoirs, through a case study in Texas. Validation of the uncalibrated model using observed hourly streamflow at 5,701 U.S. Geological Survey gages shows 26% demonstrate PBias ≤ |25%|, 11% demonstrate Nash‐Sutcliffe Efficiency (NSE) ≥ 0.25, and 6% demonstrate both PBias ≤ |25%| and NSE ≥ 0.25. When evaluating the impact of reservoirs, the analysis shows when reservoirs are included, NSE ≥ 0.25 for 56% of the gages downstream while NSE ≥ 0.25 for 11% when they are not. The results presented here provide a benchmark for the evolving hydrology program within the NWS and supports their efforts to develop a reach scale flood forecasting system for the country. 相似文献
Shallow-water octopuses have been reported as major predators of motile species in benthonic marine communities, capturing
their prey by different foraging techniques. This study assessed for the first time the feeding ecology, foraging behavior,
and defensive strategy during foraging, including the use of body patterns, to construct a general octopus foraging strategy
in a shallow water-reef system. Octopus insularis was studied in situ using visual observations and video recordings. The diet included at least 55 species of crustaceans
(70%), bivalves (17.5%), and gastropods (12.5%); however, only four species accounted for half of the occurrences: the small
crabs Pitho sp. (26.8%) and Mithrax forceps (23.9%), the bivalve Lima lima (5.3%), and the gastropod Pisania pusio (4.9%). Poke and crawl were most frequent foraging behaviors observed in the video recordings. The foraging behaviors were
associated with environmental variables and octopus body size. The sequences of foraging behavior showed characteristics of
a tactile saltatory searching predator, as well as a visual opportunist. Body patterns showed a relationship with foraging
behavior, habitat variables, and octopus body size. Mottle was the most frequent pattern, especially during poke and crawl,
in shallower depths. Dorsal light–ventral blue green was more frequent during swimming at mid-water, and Blotch was the normal
pattern during web-over by large animals. The large proportion of two species of small crabs in den remains, the intense search
for food during short hunting trips, and the intense use of cryptic body patterns during foraging trips, suggest that this
species is a ‘time-minimizing’ forager instead of a ‘rate-maximizer’. 相似文献
Environmental Chemistry Letters - Herein, we describe a simple and inexpensive protocol for the hydrothiolation of alkynes. In this context, water extract of rice straw ash (WERSA) has been proven... 相似文献
ABSTRACTAn evaluation of acute dietary exposure to pesticide residues, applying deterministic and stochastic methods, was performed for a selected group of pesticides in two representative age groups from Argentina. Thus, 28 active ingredients (a.i.) and 75 food items were evaluated for the group of 2–5-year-old children, while 9 a.i. and 59 food items were considered for the 10–49-year-old women group. A deterministic assessment was conducting following the Food and Agriculture Organization (FAO) and World Health Organization (WHO) procedure but using the national maximum residue limits (MRLs) as pesticide residue concentration data, while in the stochastic approach, a theoretical distribution modeled with the available information was used. Food consumption data were obtained from the 2004–2005 comprehensive national nutrition and health survey. The risk was estimated by comparing the short-term dietary exposure with the acute reference dose (ARfD) values for each pesticide-food combination evaluated. In the deterministic assessment, 173 (39.1%) and 40 (31.3%) combinations exceeded the ARfD thresholds for the 2–5-year-old children and 10–49-year-old women groups, respectively. This conservative study generated relevant information as a first stage of acute dietary risk assessment in Argentina. 相似文献
Agro-waste extracts are considered green solvents since they are easy to handle, readily accessible from natural waste feedstock, biodegradable and recyclable. Therefore, the employment of these extracts in reaction media has emerged as the most useful and eco-friendly alternative in modern organic chemistry. Here, we review recent developments for the generation of new carbon–carbon and carbon–heteroatom bonds mediated by agro-waste extracts. We show that these aqueous extracts have great applicability in several transformations, including condensations, oxidations, multicomponent and coupling reactions. The challenges and advantages on the use of water of agro-waste extracts in synthetic methodologies is also detail.
Environmental Science and Pollution Research - Land use changes have led to the degradation of multiple ecosystem services and affected the quality of aquatic ecosystems. The aims of this study... 相似文献