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We compared the impact of a commercial chlorination product (brand name Air RahMat) in stored drinking water to traditional boiling practices in Indonesia. We conducted a baseline survey of all households with children <5 years in four communities, made 11 subsequent weekly home visits to assess acceptability and use of water treatment methods, measured Escherichia coli concentration in stored water, and determined diarrhoea prevalence among children <5 years. Of 281 households surveyed, boiling (83%) and Air RahMat (7%) were the principal water treatment methods. Multivariable log-binomial regression analyses showed lower risk of E. coli in stored water treated with Air RahMat than boiling (risk ratio (RR) 0·75, 95% confidence interval (CI) 0·56–1·00). The risk of diarrhoea in children <5 years was lower among households using Air RahMat (RR 0·43, 95% CI 0·19–0·97) than boiling, and higher in households with E. coli concentrations of 1–1000 MPN/100 ml (RR 1·54, 95% CI 1·04–2·28) or >1000 MPN/100 ml (RR 1·86, 95% CI 1·09–3·19) in stored water than in households without detectable E. coli. Although results suggested that Air RahMat water treatment was associated with lower E. coli contamination and diarrhoeal rates among children <5 years than water treatment by boiling, Air RahMat use remained low.
Yersinia enterocolitica infection is a zoonosis with worldwide distribution, gastroenteritis being by far the most common clinical manifestation of human infection. In Gipuzkoa, northern Spain, human Y. enterocolitica infections increased from the mid-1980s to the beginning of the 21st century (from 7·9 to 23·2 annual episodes per 100 000 population) to decrease to 7·2 annual episodes per 100 000 population in the last years of the study. The hospital admission rate due to yersiniosis during the last 15 years of the study was 7·3%. More than 99% of isolates were serotype O:3. Infection affected mainly children under 5 years of age (average rate: 140 episodes per 100 000 population). The incidence in adults was low but hospitalisation increased with age, exceeding 50% in people over 64 years old.
We studied the imprints that feedback from Active Galactic Nuclei (AGN) leaves on the intracluster plasma during the assembly history of galaxy clusters. To this purpose we used state-of-the-art cosmological hydrodynamical simulations based on an updated version of the Tree-PM SPH GADGET-3 code, comparing three sets of simulations with different prescriptions for the physics of baryons (including AGN and/or stellar feedback). We explore the effect of these different physics, in particular AGN feedback, on IntraCluster medium (ICM) properties observed via Sunyaev-Zel’dovich (SZ) effect using an extended set of galaxy clusters (~100 clusters with M500 masses above 5 × 1013M⊙/h). Some of the main findings are that the scaling relation between the integrated SZ flux and the galaxy cluster total mass is in good accordance with several observed samples, especially for massive clusters, and does not show any clear redshift evolution, with the slope of the relation close to the theoretical one in the AGN feedback case. As for the scatter of this relation, we obtain a mild dependence on the cluster dynamical state.
Magnetically active late-type stars have inhomogeneities on their surfaces that cause various observable effects in the spectral lines and light curves. Such inhomogeneities are magnetic starspots, plages etc. in active regions on the photospheric and chromospheric level. The variations of the spectral lines and light curves originating in these inhomogeneities undergo modulations following stellar rotation.
ER Vul (HD 200391) is a double-lined spectroscopic binary, at a distance of 45 pc, catalogued as a short-period RS CVn binary, and has been found to present eclipses. The components have spectral types G0V/G5V, masses 1.07/0.98 M⊙, radii 1.23/1.23 R⊙ and Mv 4.8/4.6m (Strassmeier et al., 1988, and references therein). The system presents emission reversals of the H and K absorption lines (Bond, 1970; Eggen, 1978), but no information on the character of these emissions has been previously reported.
The optimal perioperative feeding strategies for neonates with CHD are unknown. In the present study, we describe the current feeding practices across a multi-institutional cohort.
Inclusion criteria for this study were as follows: all neonates undergoing cardiac surgery admitted to the cardiac ICU for ⩾24 hours preoperatively between October, 2013 and July, 2014 in the Pediatric Cardiac Critical Care Consortium registry.
The cohort included 251 patients from eight centres. The most common diagnoses included the following: hypoplastic left heart syndrome (17%), coarctation/aortic arch hypoplasia (18%), and transposition of the great arteries (22%); 14% of the patients were <37weeks of gestational age. The median total hospital length of stay was 21 days (interquartile range (IQR) 14–35) and overall mortality was 8%. Preoperative feeding occurred in 133 (53%) patients. The overall preoperative feeding rates across centres ranged from 29 to 79%. Postoperative feeds started on median day 2 (IQR 1–4); for patients with hypoplastic left heart syndrome postoperative feeds started on median day 4. Postoperative feeds were initiated in 89 (35%) patients before extubation (range across centres: 21–61%). The median cardiac ICU discharge feeding volume was 108 cc/kg/day, varying across centres. The mean discharge weight was 280 g above birth weight, ranging from +100 to 430 g across centres. A total of 110 (44%) patients had discharge feeding tubes, ranging from 6 to 80% across centres, and 40/110 patients had gastrostomy/enterostomy tubes placed. In addition, eight (3.2%) patients developed necrotising enterocolitis – three preoperatively and five postoperatively.
In this cohort, neonatal feeding practices and outcomes appear to vary across diagnostic groups and institutions. Only half of the patients received preoperative enteral nutrition; almost half had discharge feeding tubes. Multi-institutional collaboration is necessary to determine feeding strategies associated with best clinical outcomes.
The study of the feeding habits of elasmobranch populations should help to elucidate the ecological role of these fishes in the marine ecosystem. Feeding habits of the apron ray, Discopyge tschudii from San Jorge Gulf were investigated. An evaluation of whether the diet of D. tschudii changes with body size, seasons, maturity stage and sex was performed using a multiple-hypothesis modelling approach. Discopyge tschudii preyed mainly on polychaetes. The consumption of polychaetes was higher in males. Also, amphipods and siphons of clams were preyed more heavily in the cold season and Munida gregaria in the warm season. Stomatopods were consumed more with increasing body size. All prey categories were independent of maturity stage. We concluded that D. tschudii is a benthic feeder.
We present VLA 21-cm observations of the spiral galaxy ESO 481-G017 to determine the nature of remote star formation traced by an Hii region found 43 kpc and ∼800 km s−1 from the galaxy center (in projection). ESO 481-G017 is found to have a 120 kpc Hi disk with a mass of 1.2 × 1010M⊙ and UV GALEX images reveal spiral arms extending into the gaseous disk. Two dwarf galaxies with Hi masses close to 108M⊙ are detected at distances of ∼200 kpc from ESO 481-G017 and a Hi cloud with a mass of 6 × 107M⊙ is found near the position and velocity of the remote Hii region. The Hii region is somewhat offset from the Hi cloud spatially and there is no link to ESO 481-G017 or the dwarf galaxies. We consider several scenarios for the origin of the cloud and Hii region and find the most likely is a dwarf galaxy that is undergoing ram pressure stripping. The Hi mass of the cloud and Hi luminosity of the Hii region (1038.1 erg s−1) are consistent with dwarf galaxy properties, and the stripping can trigger the star formation as well as push the gas away from the stars.
The feeding habits of the apron ray, Discopyge tschudii, were investigated, off Uruguay and northern Argentina, and we tested the hypothesis that the diet changes with increasing body size, between sexes and seasons using a multiple-hypothesis modelling approach. Discopyge tschudii preys mainly on polychaetes (88.77% index of relative importance (IRI)) followed by siphons of the clam Amiantis purpurata (8.13% IRI) and amphipods (3.08% IRI). Ontogenetic, sexual and seasonal changes were found. Larger individuals of D. tschudii consumed buried polychaetes more often. The consumption of errant polychaetes was higher in males and in the cold season. Also, amphipods were preyed on more heavily by females and the number of siphons of A. purpurata consumed was higher in the cold season.
A PbTiO3 thin film prepared on silicon substrate by sol-gel technique has been studied by micro-Raman spectroscopy. The spectra, in comparison to the single crystal work, show high background in the low frequency region and Raman lines are broader, thus revealing the polycrystalline nature of the film. The frequencies of the Raman bands in the film are clearly shifted to lower frequencies compared to the corresponding ones in the single crystal or powder forms. This phenomenon is similar to the hydrostatic pressure effect on the Raman lines of PbTiO3 single crystal. The film, therefore, has grains under stress. This stress is caused by non-equilibrium defects and diffusion at the interface. Measurements at different film positions showed variation in the frequency and width of the Raman bands which are associated with the stress and grain size inhomogeneities. The measured shift in the Raman frequencies suggest grain sizes ≤l μm. XRD indicates grain size around 22 nm.
Thin films of SrBi2Nb2O9 (SBN) with thicknesses of 0.1, 0.2, and 0.4 μ were grown by Sol-gel technique on silicon, and annealed at 650°C. The SBN films were investigated by Raman scatering for the first time. Raman spectra in some of the samples present bands around 60, 167, 196, 222, 302, 451, 560, 771, 837, and 863 cm−1, which correspond to the SBN formation. The study indicates that the films are inhomogeneous, and only in samples with thicknesses 0.4 μ the SBN material was found in some places. The prominent Raman band around 870 cm−1, which is the A1g mode of the orthorhombic symmetry, is assigned to the symmetric stretching of the NbO6 octahedrals. The frequency of this band is found to shift in different places in the same sample, as well as from sample to sample. The frequency shifts and the width of the Raman bands are discussed in term of ions in non-equilibrium positions. FT-IR spectra reveal a sharp peak at 1260 cm−1, and two broad bands around 995 and 772 cm−1. The bandwidths of the latter two bands are believed to be associated with the presence of a high degree of defects in the films. The experimental results of the SBN films are compared with those obtained in SBT (T=Ta) films. X-ray diffraction and SEM techniques are also used for the structural characterization.
The synthesis, mechanical and magnetic properties of bulk composite Fe72B19.2Si4.8M4 (M=Cr, Zr) alloys obtained by a copper mould injection casting technique under a protective helium atmosphere are reported and discussed. The resultant microstructure of the composite alloys consists of crystalline Fe92Si8 and Fe2B phases embedded in a glassy matrix. The values of microhardness (Hv) show maxima for the alloy containing Cr with 10.24±0.95 GPa. The maximum value of saturation magnetization average (μ0Ms) is 1.25±0.02 T for Cr-containing alloy. The Curie temperatures (Tc) of amorphous phases are higher than 390 K for both alloys. However, the bulk composite alloys presents values for crystallization temperature (Tx) of 1289±10 K and 1140±10 K for Cr and Zr-containing alloys, respectively. These results are interpreted on the basis of the interplay between the crystalline and amorphous phases.
Ruthenium-iridium oxide films were prepared in an horizontal hot-wall MOCVD apparatus and their electrocatalytic activity was investigated in the oxygen evolution reaction. Metal-acetylacetonates were used as precursors and oxygen as the reactant gas. Appropriate deposition conditions for obtaining bi-metallic oxide films were found to be deposition temperature (Tdep), 673 K and total pressure (Ptot), 133.32 Pa. X-Ray diffraction (XRD), Rietveld refinement and scanning electron microscopy (SEM) results demonstrated that the MOCVD method is a viable alternative to grow RuxIr1−xO2 films consisted of a single-phase with a very homogeneous distribution of elements. The electrocatalytic activity of the RuxIr1−xO2 films was investigated by cyclic voltammetry and anodic polarization curves in a 0.5 M H2SO4 solution at room temperature. The single-phase Ru0.4Ir0.6O2 films showed to be very promising for the oxygen evolution reaction due to a synergistic effect.
A group of 168 families who lived in a peri-urban slum in Santiago were surveyed for 9 months. All of them had a child under 7 years of age. Medical activities and data collection were carried out at a Field Station and by means of twice-weekly visits to each home, at which time cases of diarrhoea were recorded and investigated. Faecal samples for bacteriological, parasitological and rotavirus studies were obtained during each episode. The characteristics of clinical course, hygienic practices in the family, and monthly anthropometric measurements of infants and toddlers were also recorded. The mean monthly incidence of diarrhoea was 7·1 episodes per 100 children. Of the episodes, 44·2% were associated with pathogenic bacteria, 14·4% with rotavirus, 38·4% with parasites and in 27·9% no enteropathogens were identified. It was found that adequate hygienic habits were not associated with a decreased risk of developing diarrhoea and that about 60% of children did not have diarrhoea throughout the study period. The nutritional status was adequate in most cases: weight-for-age was below the 5th percentile in 11·5% of subjects and the height-for-age was normal in all. No moderate or severe cases of malnutrition were detected.
Five class II H-2 genes borne by t chromosomes were partially sequenced: borne by the tTuw10 chromosome of EDY589 (H-2w2); and borne by the tTuw8 chromosome of CR0437 (H-2w57), as well as and borne by the tTuw7 chromosome of CR0435 (H-2w37). These genes are representatives of the three major groups of alleles found associated with t chromosomes. The sequenced part consisted of almost the entire exon 2 and the entire exon 3 coding for the first and the second domain of the β polypeptide chains, respectively. The sequence was compared with the published sequences of Aβ and Eβ alleles borne, by non-t chromosomes. The comparison revealed that the t-associated alleles are no more similar to one another than they are to the corresponding genes present on non-t chromosomes in laboratory mice. This divergence in the nucleotide sequence among the class II genes is interpreted as evidence that the t complex is very old.
We present here a detailed study of FF UMa (2RE J0933+624), a recently discovered, X-ray/EUV selected, active binary system with strong Hα emission. By using high-resolution echelle spectroscopic observations taken during five observing runs from 1998 to 2004, we derived precise radial velocities that allowed us to determine the orbital solution of the system at different epochs. Analyzing these orbital solutions, together with a previous one determined in 1993 by other authors, we have found a change in the heliocentric Julian date on conjunction (Tconj) that can be explained by a change with time in the orbital period of the system. The relative amplitude of the orbital period variation derived from these data was dP/P ≈ 5 x 10−4, which is larger than the variations found in other similar chromospherically active binaries like AR Lac and HR 1099. This orbital period variation can be related (Applegate 1992; Lanza 1998, 2006) with the modulation of the gravitational quadrupole-moment of its magnetically active secondary star produced by angular momentum exchanges within its convective envelope. In addition, using these observations, we have determined the stellar parameters of the components and we have carried out a study of the chromospheric activity using all the optical indicators from Ca ii H&K to Ca ii IRT lines.
The tobacco-feeding race of Myzus persicae (Sulzer), formerly known as M. nicotianae Blackman, was introduced into Chile during the last decade. In order to evaluate the genetic diversity and insecticide resistance status of Chilean tobacco aphid populations, a field survey was conducted in 35 tobacco fields covering a 300 km latitudinal survey. The populations sampled were characterized using microsatellite markers and morphometric multivariate analysis. Insecticide resistance levels were assessed through a microplate esterase assay and the mutation status of the kdr gene. All samples collected corresponded to the same anholocyclic aphid genotype, and showed morphological variation within the range expected for the tobacco-feeding race of M. persicae. Esterase activity showed the level and variability expected for an R1 clone lacking mutations in the sodium channels (susceptible kdr), thus corresponding to a type slightly resistant to organophosphate and carbamate, and susceptible to pyrethroid insecticides.
The Chimalapas region, in eastern Oaxaca, Mexico, holds lowland rainforests, tropical dry forests, and cloud forests typical of the Neotropics, as well as montane pine and pine-oak forests more typical of the Nearctic. Totaling more than 600,000 ha, much of the region is forested, and in a good state of preservation. The Chimalapas avifauna is by far the most diverse for any region of comparable size in the country, totalling at least 464 species in the region as a whole (with more than 300 species in the lowland rainforest) representing 44% of the bird species known from Mexico. Within the region, the humid Atlantic lowlands hold 317 species, the montane regions 113 species, and the southern dry forested lowlands 216 species. Important species present in the region include Harpy Eagle Harpia harpyja and several other large eagles, Black Penelopina nigra and probably Horned Oreophasis derbianus Guans, Scarlet Macaw Ara macao, Cinnamon-tailed Sparrow Aimophila sumichrasti, Rose-bellied Bunting Passerina rositae, and Resplendent Quetzal Pharomachrus mocinno. The area holds immense lowland rainforests and cloud forests that rank among the largest and best preserved in all of Mesoamerica, including a complete lowland-to-highland continuum, with entire watersheds preserved more or less intact.
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