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Background and aims: The intensity of extreme rainfall events is increasing in many regions of the world, with important impacts on community dynamics and ecosystem functioning especially in water-limited ecosystems. The impact of the intensification of extreme precipitation on mixed communities of CAM plants and dryland C4 grasses remains poorly understood. Methods: Through a set of greenhouse experiments we investigated the effect of increasing intraseasonal rainfall variability on two separate pairs of CAM and C4 grass species (C. imbricata and B. eriopoda; O. phaeacantha and B. curtipendula) that coexist in arid grasslands across the southwest USA. Results: The increased rainfall variability did not significantly change the biomass of C. imbricata while increasing the biomass of B. eriopoda when these two species coexisted. More extreme rainfall regimes caused a 24.8% decrease in B. curtipendula (grass) biomass, compared with a 71.3% decline in the O. phaeacantha CAM plant. Significantly lower nocturnal carbon assimilation rates and higher stem volume-to-surface area ratios were found in CAM plants in mixture than in monoculture. Conclusions: Our study suggests that C4 grasses may outcompete CAM plants through greater access to deep soil water under increased rainfall variability and highlights the important role of hydrologic conditions as determinants of the competitive relations between CAM plants and grasses, their community composition, and ecological resilience in dryland ecosystems. [ABSTRACT FROM AUTHOR]

The 1996 Telecommunications Act opened the monopolistic US local telephone industry to new entrants. However, substantial entry costs have prevented some markets from becoming competitive. We study various subsidy policies designed to encourage entry. We estimate a dynamic entry game using data on potential and actual entrants, allowing for heterogeneous option values of waiting. We find that subsidies to smaller markets are more cost effective in reducing monopoly markets, but subsidies to only lower-cost firms are less cost effective than a nondiscriminatory policy. Subsidies in only early periods reduce the option value of waiting and accelerate the arrival of competition. [ABSTRACT FROM AUTHOR]

Significant increases in summer precipitation have occurred in the midwestern United States over the last century for reasons that remain unclear. It is postulated that the expansion of irrigation and cropland in the central United States over the past 60 yr has been a major contributor to these observed increases in precipitation. As a first step toward attribution of these precipitation changes, a detailed analysis of observed daily summer precipitation frequency and intensity is conducted for the contiguous United States over multiple spatial scales and time periods from 1895 to 2011. Robust increases in precipitation frequency, total precipitation, and moderate to heavy precipitation intensity are identified during July and August in the midwestern United States. Analysis of changes in mean monthly precipitation from the early to late twentieth century initially points to increasing frequency as the source of increasing monthly precipitation in the midwestern United States during the summer, especially during August; however, these large frequency increases are not unique to the summer. On the other hand, changes in precipitation intensity and total precipitation are both greatest during July and August and coincide spatially in the midwestern United States. Additionally, the greatest intensity change occurs downwind of the most heavily irrigated regions, especially for the period between 1950 and 1980 when irrigation rapidly intensified. Thus, the seasonality and location of these regional signatures of increasing precipitation intensity (and total precipitation) are found to be broadly consistent with spatiotemporal trends in irrigation and cropland in the central United States and may be indicative of a causal link. [ABSTRACT FROM AUTHOR]

Summary: We explore the influence of long-term, large-scale irrigational pumping on spatial and seasonal patterns of streamflow regimes in the High Plains aquifer using extensive observational data to elucidate the effects of regional-scale human alterations on the hydrological cycle. Streamflow, groundwater and precipitation time series spanning all or part of the period of intensive irrigation development (1940–1980) in the region were analyzed for trend and step changes using the non-parametric Mann–Kendall test and the parametric Student’s t-test, respectively. Based on several indicators to evaluate the streamflow–groundwater connection degree over the High Plains aquifer, we found a systematic decrease in the hydraulic connection between groundwater and streamflow from the Northern High Plains to Southern High Plains. Trends and step changes are consistent with this regional pattern. Decreasing trends in annual and dry-season (mean July–August) streamflow and increasing trends in the number of low-flow days are prevalent in the Northern High Plains with a gradual decrease in trend detection towards the south. Additionally, field significance of trends was assessed by the Regional Kendall’s S test over the period of most intensive irrigation development (1940–1980). The step-change results imply that the observed decreases in streamflow are likely attributable to the significant declines in groundwater levels and unlikely related to changes in precipitation because the majority of precipitation data over the region did not reveal any significant changes. Thus, it is very likely that extensive irrigational pumping have caused streamflow depletion, more severely, in the Northern High Plains, and to a lesser extent in the Southern High Plains over the period of study. [ABSTRACT FROM AUTHOR]

Abstract: Background: Two rotavirus vaccines are currently approved in the United States: 3-dose RotaTeq (RV5; Merck & Co., Inc., Whitehouse Station, NJ, USA) is administered at ages 2, 4, and 6 months; and 2-dose Rotarix (RV1; GlaxoSmithKline, Research Triangle Park, NC, USA) is administered at ages 2 and 4 months. Our objective was to compare rotavirus vaccine series completion and dosing schedule compliance between cohorts of infants who received these vaccines. Methods: Infants aged less than 1 year who initiated a rotavirus vaccine series between 01 January 2009 and 30 June 2009 were identified in US health insurance claims data. Cohorts were formed based on vaccine brand use. Series completion and compliance with the FDA-approved and ACIP-recommended harmonized schedules were analyzed descriptively and a log binomial model was used to estimate the difference in series completion by vaccine brand while adjusting for demographic variables. Results: Among infants in the RV1 and RV5 cohorts (N =55,584), 84.3% completed a full series. A greater proportion of the RV1 cohort than the RV5 cohort completed their series (91.0% vs. 83.4%; P <0.001; multivariate-adjusted relative risk 1.07; 95% CI 1.06–1.08). In the RV1 and RV5 cohorts, respectively, 75.0% and 59.5% of infants were fully compliant with the FDA-approved administration schedule for their vaccine (P <0.001); 83.3% and 76.4% of infants were fully compliant with the harmonized schedule (P <0.001). Conclusions: The proportion of infants that completed the series was greater and compliance with respective FDA-approved and harmonized dosing schedules was higher among infants vaccinated with RV1 than among infants who received RV5. [Copyright &y& Elsevier]

Most rivers exchange water with surrounding aquifers 1,2 . Where groundwater levels lie below nearby streams, streamwater can infiltrate through the streambed, reducing streamflow and recharging the aquifer 3 . These 'losing' streams have important implications for water availability, riparian ecosystems and environmental flows 4-10 , but the prevalence of losing streams remains poorly constrained by continent-wide in situ observations. Here we analyse water levels in 4.2 million wells across the contiguous USA and show that nearly two-thirds (64 per cent) of them lie below nearby stream surfaces, implying that these streamwaters will seep into the subsurface if it is sufficiently permeable. A lack of adequate permeability data prevents us from quantifying the magnitudes of these subsurface flows, but our analysis nonetheless demonstrates widespread potential for streamwater losses into underlying aquifers. These potentially losing rivers are more common in drier climates, flatter landscapes and regions with extensive groundwater pumping. Our results thus imply that climatic factors, geological conditions and historic groundwater pumping jointly contribute to the widespread risk of streams losing flow into surrounding aquifers instead of gaining flow from them. Recent modelling studies 10 have suggested that losing streams could become common in future decades, but our direct observations show that many rivers across the USA are already potentially losing flow, highlighting the importance of coordinating groundwater and surface water policy.

Background: The objective of this report is to summarize common deficiencies identified in the filing reviews of abbreviated new drug applications (ANDAs) with clinical endpoint bioequivalence studies and skin irritation, sensitization, and adhesion (I/S/A) studies received by the US Food and Drug Administration (FDA) between 2007 and 2017, to help applicants avoid common deficiencies, minimize "refuse-to-receive" (RTR) actions, "information requests," and ANDA approval delays., Methods: Multiple internal FDA databases were searched to evaluate and summarize common deficiencies identified in ANDA submissions containing clinical endpoint studies and skin I/S/A studies that required review by the Division of Clinical Review. A total of 275 ANDA submissions with filing reviews from January 2007 to June 2017 were analyzed in this report., Results: Two hundred eighteen (79.3%) filing reviews contained one or more deficiencies. Seventy-nine (28.7%) ANDAs were issued RTR letters because of major clinical deficiencies, specifically bioequivalence and clinical deficiencies, accounting for 9% of overall identified deficiencies. Twenty-two other categories of deficiencies are summarized into 4 main categories: missing information related to the clinical studies other than data sets (38%), missing data sets (35%), formulation issues (12%), and organization/format issues (6%)., Conclusions: The most common deficiency in the "missing information related to the clinical studies other than data sets" category was "missing clarification of information" (22%). We also noted that the Division of Filing Review has identified these same types of deficiencies since assuming responsibility of the filing assessment for ANDAs with clinical endpoint BE studies and skin I/S/A studies. In conclusion, to minimize "refuse-to-receive" actions, "information requests," and approval of ANDA delays for generic drug products, applicants should submit full clinical study reports, including all data sets for drug products recommending clinical studies.

Background: Cancer stage is critical for treatment planning and assessing disease prognosis. The percentage of unknown staged cancer cases varies considerably across state cancer registries; factors contributing to the variations in unknown stage have not been reported in the literature before. The purpose of this study was to examine whether these variations were influenced by demographic and/or clinical factors as well as the type of reporting facility., Methods: Invasive colorectal, lung, female breast, and prostate cancers diagnosed between 2004 and 2007 were obtained from the North American Association of Central Cancer Registries (NAACCR); 47 population-based cancer registries in the United States were included. The unknown stage was based on Summary Stage 2000 codes derived from Collaborative Stage Version 1 (CSv1). Relative importance analysis was used to identify variables that were essential in predicting unknown stage. Using state central registries as analytical units, multiple linear regression was used to evaluate factors associated with the percentage of unknown stage by cancer site; potential outlier registries with a high percentage of unknown stage cases were identified using boxplots and standardized residuals., Results: Overall, lung cancer had the highest percentage of unknown stage (8.3%) and prostate cancer had the largest variation of unknown stage among registries (0.6%-18.1%). The percentages of neoplasms not otherwise specified (NOS) histology, non-microscopic confirmation, and non-hospital reporting source were positively associated (p less than 0.05) with percentage of unknown stage for all studied cancer sites before adjustment. Variables that retained a positive association with unknown stage including all demographic and clinical variables, year of diagnosis, and type of reporting source were black race, metropolitan area less than 1 million population, histologies of neoplasms NOS or epithelial neoplasms NOS, diagnosis year 2005, and non-hospital reporting source for colorectal cancer; metropolitan area less than 1 million population, neoplasms NOS histology, and non-hospital reporting source for female breast; and diagnosis year 2005 and non-hospital reporting source for prostate. After adjustment, none of the predictors were significant for lung cancer. We observed 1 potential outlier registry each for colorectal, lung and female breast cancers., Conclusions: Factors associated with unknown stage differ by cancer site; however, the type of reporting source is an important predictor of unknown stage for all cancers except lung after adjustment. Central registries with high percentage of unknown stage should be made aware of their data quality issue(s). As a result, these registries can investigate those factors and provide training to registrars to improve their cancer data quality.

In addition to being used as a tool for ecological understanding, management and conservation of migratory waterfowl rely heavily on distribution models; yet these models have poor accuracy when compared to models of other bird groups. The goal of this study is to offer methods to enhance our ability to accurately model the spatial distributions of six migratory waterfowl species. This goal is accomplished by creating models based on species-specific annual cycles and introducing a depth to water table (DWT) data set. The DWT data set, a wetland proxy, is a simulated long-term measure of the point either at or below the surface where climate and geological/topographic water fluxes balance. For species occurrences, the USGS' banding bird data for six relatively common species was used. Distribution models are constructed using Random Forest and MaxEnt. Random Forest classification of habitat and non-habitat provided a measure of DWT variable importance, which indicated that DWT is as important, and often more important, to model accuracy as temperature, precipitation, elevation, and an alternative wetland measure. MaxEnt models that included DWT in addition to traditional predictor variables had a considerable increase in classification accuracy. Also, MaxEnt models created with DWT often had higher accuracy when compared with models created with an alternative measure of wetland habitat. By comparing maps of predicted probability of occurrence and response curves, it is possible to explore how different species respond to water table depth and how a species responds in different seasons. The results of this analysis also illustrate that, as expected, all waterfowl species are tightly affiliated with shallow water table habitat. However, this study illustrates that the intensity of affiliation is not constant between seasons for a species, nor is it consistent between species.