Spatial distribution and risk factors of Schistosoma haematobium and hookworm infections among schoolchildren in Kwale, Kenya

Background: Large-scale schistosomiasis control programs are implemented in regions with diverse social and economic environments. A key epidemiological feature of schistosomiasis is its small-scale heterogeneity. Locally profiling disease dynamics including risk factors associated with its transmission is essential for designing appropriate control programs. To determine spatial distribution of schistosomiasis and its drivers, we examined schoolchildren in Kwale, Kenya. Methodology/Principal findings: We conducted a cross-sectional study of 368 schoolchildren from six primary schools. Soil-transmitted helminths and Schistosoma mansoni eggs in stool were evaluated by the Kato-Katz method. We measured the intensity of Schistosoma haematobium infection by urine filtration. The geometrical mean intensity of S. haematobium was 3.1 eggs/10 ml urine (school range, 1.4?9.2). The hookworm geometric mean intensity was 3.2 eggs/g feces (school range, 0?17.4). Heterogeneity in the intensity of S. haematobium and hookworm infections was evident in the study area. To identify factors associated with the intensity of helminth infections, we utilized negative binomial generalized linear mixed models. The intensity of S. haematobium infection was associated with religion and socioeconomic status (SES), while that of hookworm infection was related to SES, sex, distance to river and history of anthelmintic treatment. Conclusions/Significance: Both S. haematobium and hookworm infections showed micro-geographical heterogeneities in this Kwale community. To confirm and explain our observation of high S. haematobium risk among Muslims, further extensive investigations are necessary. The observed small scale clustering of the S. haematobium and hookworm infections might imply less uniform strategies even at finer scale for efficient utilization of limited resources

A catalog of video records of the 2013 Chelyabinsk superbolide

The Chelyabinsk superbolide of February 15, 2013, was caused by the atmospheric entry of a ~19 m asteroid with a kinetic energy of 500 kT TNT just south of the city of Chelyabinsk, Russia. It was a rare event; impacts of similar energy occur on the Earth only a few times per century. Impacts of this energy near such a large urban area are expected only a few times per 10 000 years. A number of video records obtained by casual eyewitnesses, dashboard cameras in cars, security, and traffic cameras were made publicly available by their authors on the Internet. These represent a rich repository for future scientific studies of this unique event. To aid researchers in the archival study of this airburst, we provide and document a catalog of 960 videos showing various aspects of the event. Among the video records are 400 distinct videos showing the bolide itself and 108 videos showing the illumination caused by the bolide. Other videos show the dust trail left in the atmosphere, the arrival of the blast wave on the ground, or the damage caused by the blast wave. As these video recordings have high scientific, historical, and archival value for future studies of this airburst, a systematic documentation and description of records is desirable. Many have already been used for scientific analyses. We give the exact locations where 715 videos were taken as well as details of the visible/audible phenomena in each video recording. An online version of the published catalog has been developed and will be regularly updated to provide a long–term database for investigators

Mobilita lithných iontů ve sklech systému B2O3-GeO2-P2O5

Effect of the structural changes, electrical conductivity, and dielectric properties on the addition of a third glass-former, GeO2, to the borophosphate glasses, 40Li2O−10B2O3−(50−x)P2O5−xGeO2, x = 0−25 mol %, has been studied.Byl studován vliv přídavku GeO2, jako třetího sklotvorného oxidu, na strukturu, elektrickou vodivost a dielektrické vlastnosti lithných borofosforečnanových skel, připravených v kompoziční řadě 40Li2O−10B2O3−(50−x)P2O5−xGeO2 (x = 0−25 mol %)

Lindelöf spaces C(X) over topological groups

Theorem 1 proves (among the others) that for a locally compact topological group X the following assertions are equivalent: (i) X is metrizable and sigma-compact. (ii) C-p(X) is analytic. (iii) C-p(X) is K-analytic. (iv) C-p(X) is Lindelof. (v) C-c(X) is a separable metrizable and complete locally convex space. (vi) C,(X) is compactly dominated by irrationals. This result supplements earlier results of Corson, Christensen and Calbrix and provides several applications, for example, it easily applies to show that: (1) For a compact topological group X the Eberlein, Talagrand, Gul'ko and Corson compactness are equivalent and any compact group of this type is metrizable. (2) For a locally compact topological group X the space C-p(X) is Lindelof iff C-c(X) is weakly Lindelof. The proofs heavily depend on the following result of independent interest: A locally compact topological group X is metrizable iff every compact subgroup of X has countable tightness (Theorem 2). More applications of Theorem 1 and Theorem 2 are provided