Termites (Blattodea: Termitidae) diversity and assemblages in different yam fields habitats in central Benin

Open Access JournalTermites are known to cause significant economic losses in yam fields. Therefore, assessing diversity and abundance of termites in yam fields is critical for their control. In this study, we compared the specific richness, abundance, and diversity of functional groups of termite pests in upland and lowland yam fields, across 15 villages using the standardized belt transect method. The specific termite diversity encountered in yam fields was compared with that of the Agoua classified forest. In general, eight genera classified into four subfamilies (Nasutitermitinae, Macrotermitinae, Amitermitinae and Coptotermitinae) grouped into two families (Termitidae and Rhinotermitidae) were identified. The highest number of the species (13) were identified in upland fields while the lowest number (10) were identified in the lowlands. Termite fauna collected from yam fields and from the Agoua forest were distinct, as showed by the similarity index. Amitermes evuncifer (Silvestri) was the most widely distributed and the most dominant termite species in upland yam fields while in lowland yam fields it was Macrotermes subhyalinus (Rambur). Three functional groups were observed with humus feeders only found in upland yam fields. Principal component analysis classified the 24 sampled transects into four groups with different termites feeding groups. The dominance of non-fungus-growers was observed in the groups mostly composed of transects in uplands yam fields. Three nesting habitats were represented (epigeal mound, wood, and subterranean). The results of this present research could help to develop efficient strategies against the identified key yam termite pests

Generation and Structure of Solitary Rossby Vortices in Rotating Fluids

The formation of zonal flows and vortices in the generalized Charney-Hasegawa-Mima equation is studied. We focus on the regime when the size of structures is comparable to or larger than the deformation (Rossby) radius. Numerical simulations show the formation of anticyclonic vortices in unstable shear flows and ring-like vortices with quiescent cores and vorticity concentrated in a ring. Physical mechanisms that lead to these phenomena and their relevance to turbulence in planetary atmospheres are discussed.Comment: 3 pages in REVTeX, 5 postscript figures separately, submitted to Phys. Rev.

Burden and contributing factors to overweight and obesity in young adolescents in Addis Ababa, Ethiopia.

The prevalence of overweight/obesity in adolescents has increased globally, including in low- and middle-income countries. Early adolescence provides an opportunity to develop and encourage positive health and behavioural practices, yet it is an understudied age group with limited information to guide and inform appropriate interventions. This study aims to determine the prevalence of overweight/obesity in young adolescents, aged between 10 and 14 years attending public schools in Addis Ababa, Ethiopia, and to explore the contributing factors. A cross-sectional school-based study was conducted. Adolescents completed individual questionnaires. Weight (kg) and height (m) measurements were converted to BMI-for-age and gender z-scores. Multivariate regression analysis was conducted to determine the associated factors. The overall prevalence of overweight/obesity was 8% among adolescents aged 10-14 years and it was significantly higher in females (13%) than males (2%). The diet quality for the majority of the adolescents was inadequate, putting them at risk for poor health outcomes. The contributors to overweight/obesity were different between males and females. Age and no access to a flush toilet were negatively associated with overweight/obesity in males and access to a computer, laptop or tablet was positively associated. In females, menarche was positively associated with overweight/obesity. Living with only their mother or another female adult and an increase in physical activity were negatively associated with overweight/obesity. There is a need to improve the diet quality of young adolescents in Ethiopia and understand the reasons why females are less physically active to limit the risk of poor diet-related health outcomes

A multi-scale comparison of modeled and observed seasonal methane emissions in northern wetlands

Wetlands are the largest global natural methane (CH4) source, and emissions between 50 and 70° N latitude contribute 10–30% to this source. Predictive capability of land models for northern wetland CH4 emissions is still low due to limited site measurements, strong spatial and temporal variability in emissions, and complex hydrological and biogeochemical dynamics. To explore this issue, we compare wetland CH4 emission predictions from the Community Land Model 4.5 (CLM4.5-BGC) with siteto regional-scale observations. A comparison of the CH4 fluxes with eddy flux data highlighted needed changes to the model’s estimate of aerenchyma area, which we implemented and tested. The model modification substantially reduced biases in CH4 emissions when compared with CarbonTracker CH4 predictions. CLM4.5 CH4 emission predictions agree well with growing season (May–September) CarbonTracker Alaskan regional-level CH4 predictions and sitelevel observations. However, CLM4.5 underestimated CH4 emissions in the cold season (October–April). The monthly atmospheric CH4 mole fraction enhancements due to wetland emissions are also assessed using the Weather Research and Forecasting-Stochastic Time-Inverted Lagrangian Transport (WRF-STILT) model coupled with daily emissions from CLM4.5 and compared with aircraft CH4 mole fraction measurements from the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) campaign. Both the tower and aircraft analyses confirm the underestimate of cold-season CH4 emissions by CLM4.5. The greatest uncertainties in predicting the seasonal CH4 cycle are from the wetland extent, coldseason CH4 production and CH4 transport processes. We recommend more cold-season experimental studies in highlatitude systems, which could improve the understanding and parameterization of ecosystem structure and function during this period. Predicted CH4 emissions remain uncertain, but we show here that benchmarking against observations across spatial scales can inform model structural and parameter improvements

Cold season emissions dominate the Arctic tundra methane budget

Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for >= 50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the "zero curtain" period, when subsurface soil temperatures are poised near 0 degrees C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 +/- 5 (95% confidence interval) Tg CH4 y(-1), similar to 25% of global emissions from extratropical wetlands, or similar to 6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming.Peer reviewe

Cholinesterase Inhibitors and Hospitalization for Bradycardia: A Population-Based Study

Laura Park-Wyllie and colleagues examined the health records of more than 1.4 million older adults and show that initiation of cholinesterase inhibitor therapy is associated with a more than doubling of the risk of hospitalization for bradycardia

Influence of emphysema distribution on pulmonary function parameters in COPD patients

Objective: To evaluate the impact that the distribution of emphysema has on clinical and functional severity in patients with COPD. Methods: The distribution of the emphysema was analyzed in COPD patients, who were classified according to a 5-point visual classification system of lung CT findings. We assessed the influence of emphysema distribution type on the clinical and functional presentation of COPD. We also evaluated hypoxemia after the six-minute walk test (6MWT) and determined the six-minute walk distance (6MWD). Results: Eighty-six patients were included. The mean age was 65.2 ± 12.2 years, 91.9% were male, and all but one were smokers (mean smoking history, 62.7 ± 38.4 pack-years). The emphysema distribution was categorized as obviously upper lung-predominant (type 1), in 36.0% of the patients; slightly upper lung-predominant (type 2), in 25.6%; homogeneous between the upper and lower lung (type 3), in 16.3%; and slightly lower lung-predominant (type 4), in 22.1%. Type 2 emphysema distribution was associated with lower FEV1 , FVC, FEV1 /FVC ratio, and DLCO. In comparison with the type 1 patients, the type 4 patients were more likely to have an FEV1 < 65% of the predicted value (OR = 6.91, 95% CI: 1.43-33.45; p = 0.016), a 6MWD < 350 m (OR = 6.36, 95% CI: 1.26-32.18; p = 0.025), and post-6MWT hypoxemia (OR = 32.66, 95% CI: 3.26-326.84; p = 0.003). The type 3 patients had a higher RV/TLC ratio, although the difference was not significant. Conclusions: The severity of COPD appears to be greater in type 4 patients, and type 3 patients tend to have greater hyperinflation. The distribution of emphysema could have a major impact on functional parameters and should be considered in the evaluation of COPD patients