Seroprevalence of hepatitis B surface antigen among pregnant women attending the Hospital for Women & Children in Koutiala, Mali

Objective. To establish the rate of seroprevalence of the hepatitis B surface antigen in pregnant women in south-eastern Mali, and to decrease mother-to-child transmission. Methods. In a descriptive cross-sectional comparison study, 3 659 pregnant women attending a non-governmental hospital in Koutiala, Mali, during 2008 and 2009 were screened for the hepatitis B surface antigen during antenatal clinic attendance or when admitted for delivery. A chart review compared the hepatitis B virus (HBV)-positive women to HBV-negative women used as controls to identify potential risk factors for HBsAg positivity. The variables compared were age, parity, type of genital excision, birthweight of baby and HIV status. Results. A total of 293 (8.0%) pregnant women tested positive for HBsAg. Their average age was 27.6 years, average parity of 2.8 births, 90% had Type 2 genital excision, 21% had low-birthweight infants, and 14 (0.4%) women also tested positive for HIV. Infants born to HbsAg-positive women were immunised with the hepatitis B vaccine in the delivery room. Two hundred and eighty-four HBVnegative women were compared with the HBV-positive women. None of the differences of means or relationships was statistically insignificant. Conclusion. In view of the high endemicity and lack of easily identifiable risk factors, free maternal HBV screening should be provided to all women in Mali, and the infants born to HBsAgpositive women should be immunised within 12 hours of birth. S Afr Med J 2012;102:47-4

Enigmatic deep-water mounds on the Orphan Knoll, Labrador Sea

Deep-sea mounds can have a variety of origins and may provide hard-substrate features in depths that are normally dominated by mud. Orphan Knoll, a 2 km high bedrock horst off northeast Newfoundland, hosts more than 200 mounds, or mound complexes, of unknown composition, in water depths of 1720–2500 m. Most mounds are 10–600 m high, with average mound height 187 m, and 1–3 km wide. The study objective was to characterize the size, shape, orientation, and composition of the enigmatic Orphan Knoll mounds, in order to determine their age and origin. Archival ship-based side-scan sonar, multibeam sonar, airgun, high-resolution sparker and 3.5 kHz acoustic sub-bottom profiling, and newly acquired ship-based multibeam sonar, video transects by remotely operated vehicle (ROV), rock samples, and near-bottom multibeam sonar data were analyzed. Four mounds were studied during two ROV dives. Archival sidescan sonar data show > 200 mounds. Sparker profiles show that the mound crests are covered by condensed stratified Quaternary sediment and airgun seismic data show faults reaching near the seafloor. New multibeam sonar data show mounds are dominantly conical to elliptical in shape, but without preferred orientation or alignment. Remotely operated vehicle (ROV) transects and near-bottom multibeam showed that three mounds were rounded and symmetrically arranged, while a fourth was more asymmetrical, with steep faces on the southwestern and southeastern flanks, where finely bedded to massive sedimentary bedrock outcropped dipping 15–45°SW. Rock samples from the mounds include Eocene calcareous ooze and mid-Miocene bedded pelagic limestone. Thick ferromanganese crusts were found on many surfaces, obscuring possible outcrops from physical sampling. Polymetallic nodules were found on the slope of one mound. Ice-rafted detritus, including igneous and metamorphic rocks and Paleozoic limestone and dolostone, was common in the sediments immediately surrounding the mounds. Quaternary sub-fossil solitary scleractinian corals accumulated over a span of at least 0.18 Ma at the base of one mound. The presence of uplifted condensed Eocene-Miocene rocks on the mounds and faulting in seismic profiles suggest uplift during reactivation of old rift-related faults during the Neogene, with seabed mass wasting creating residual mounds, which were then draped by Quaternary proglacial muds. Sculpting of hemipelagic Quaternary sediment by bottom currents probably contributed to mound morphology

A social relations analysis of young children's trust in their peers across the early years of school

Two hundred and five (103 female and 102 male) children enrolled in school years 1 and 2 in the United Kingdom (mean age 6 years 1 month at Time 1) were tested twice over a 1-year period. The children reported the promise keeping and secret keeping behaviours of classmates (all peers and same-gender peers) and provided friendship nominations (Time 2 only). Round robin social relations analyses for all peers and same-gender peers revealed: (a) perceiver variance, demonstrating consistent individual differences in trust beliefs in peers; (b) target variance, demonstrating consistent individual differences in eliciting trust from peers; and, (c) dyadic reciprocity, demonstrating reciprocal trust between individuals. Replicability across measures, stability, and cross-measure stability of these effects were found for all peers only. As hypothesised, the perceiver and target effects of trust were associated with the number of friendships. The findings support the concl usion that young children demonstrate multiple components of trust in dyadic relationships, which are associated with their social relationships

Conhecimento da equipe de enfermagem sobre avaliação comportamental de dor em paciente crítico

Estudo transversal prospectivo que teve como objetivo descrever o conhecimento da equipe de enfermagem sobre uma avaliação comportamental de dor. Realizado em hospital privado da cidade de São Paulo, Brasil, em novembro de 2011, com profissionais de enfermagem de uma UTI geral adulto. Estes responderam a um questionário com dados sociodemográficos e questões referentes ao conhecimento sobre uma avaliação comportamental de dor. A análise dos dados foi descritiva e a média de acertos por categoria profissional foi comparada por teste Mann-Whitney. Dos 113 participantes, mais de 70% demonstraram ter conhecimento sobre os principais aspectos dessa avaliação e não houve diferença estatisticamente significativa entre as categorias profissionais. Concluiu-se que o conhecimento dos profissionais foi satisfatório, mas pode ser aprimorado.

The biogeochemical impact of glacial meltwater from Southwest Greenland

Biogeochemical cycling in high-latitude regions has a disproportionate impact on global nutrient budgets. Here, we introduce a holistic, multi-disciplinary framework for elucidating the influence of glacial meltwaters, shelf currents, and biological production on biogeochemical cycling in high-latitude continental margins, with a focus on the silica cycle. Our findings highlight the impact of significant glacial discharge on nutrient supply to shelf and slope waters, as well as surface and benthic production in these regions, over a range of timescales from days to thousands of years. Whilst biological uptake in fjords and strong diatom activity in coastal waters maintains low dissolved silicon concentrations in surface waters, we find important but spatially heterogeneous additions of particulates into the system, which are transported rapidly away from the shore. We expect the glacially-derived particles – together with biogenic silica tests – to be cycled rapidly through shallow sediments, resulting in a strong benthic flux of dissolved silicon. Entrainment of this benthic silicon into boundary currents may supply an important source of this key nutrient into the Labrador Sea, and is also likely to recirculate back into the deep fjords inshore. This study illustrates how geochemical and oceanographic analyses can be used together to probe further into modern nutrient cycling in this region, as well as the palaeoclimatological approaches to investigating changes in glacial meltwater discharge through time, especially during periods of rapid climatic change in the Late Quaternary

Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run

Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets. © 2022. The Author(s). Published by the American Astronomical Society