Prevalence, correlates and patterns of waterpipe smoking among secondary school students in southeast London: a cross-sectional study

BACKGROUND: Waterpipe smoking is growing worldwide, but little is known of its epidemiology in the UK due to its absence from national health surveys. We sought to address this by calculating the prevalence of waterpipe smoking among secondary school students in southeast London. METHODS: We conducted a pooled secondary analysis of routine health surveillance surveys among 11–17 year olds in convenience-sampled secondary schools from three ethnically-diverse areas of southeast London. We calculated ever (lifetime) waterpipe use, and compared its sociodemographic correlates to ever (lifetime) cigarette use. In one area we collected data on patterns of waterpipe use. RESULTS: Of 2,098 respondents (mean age 14.1 ± 1.7 years, 55.7 % male, 46.6 % of black ethnicity), ever waterpipe use was 39.6 % (95 % CI 37.6–41.7 %) and was higher than that for ever cigarette use (32.4 %; 95 % CI 30.5–34.4). While waterpipe users were significantly and independently more likely to be male and of non-white ethnicities, at least 30 % of all age, gender and ethnic sub-groups had tried waterpipe smoking. In contrast, cigarette users were more likely to be older and of white ethnicity. In one of the three areas, over a quarter of waterpipe users were occasional or regular waterpipe smokers, and most were introduced to and currently used waterpipe in waterpipe-serving premises or friends’ homes. CONCLUSIONS: Waterpipe smoking prevalence was high in southeast London, and users exhibited a different sociodemographic profile to cigarette users. Waterpipe should be included in national health surveys of young people. National surveillance is warranted to help develop suitable interventions to prevent uptake and promote cessation

The Fisheries of an Ojibwa Community in Northern Ontario

Subsistence fishing provides an important source of food for the remote Ojibwa community of Webequie, located along the Winisk River in northern Ontario. Field observations during the summer of 1988 were combined with a recall survey to estimate catches from October 1987 through September 1988. Of 133 potential fishermen, 90 were surveyed. The total community harvest was estimated to be 83,810 fish, round weight 108,210 kg. After adjustments, this provided 118 kg round weight/person/year, or 0.21 kg/person/day edible fish for consumption. Lake whitefish (Coregonus clupeaformis), walleye (Stizostedion vitreum), northern pike (Esox lucius) and suckers (Catostomus commersoni and C. catostomus) were dominant in the catch. Lake sturgeon (Acipenser fluvescens) attracts special fishing effort. Older males (>40 years old) are the primary fishermen. Fixed gill nets take 95% of the harvest, most of which is consumed. Commercial fishing seems to be disappearing. Recreational fishing is a potential source of revenue. Subsistence fishing tends to be overlooked in development and management schemes but is clearly an important activity.Key words: subsistence fishing, Ojibwa, native harvest survey, northern Ontario fisheriesMots clés: pêche de subsistance, Ojibwa, relevés des prises effectuées par les aborigines, les pêches du nord de l’Ontari

Water calcium concentration modifies whole-body calcium uptake in sea bream larvae during short-term adaptation to altered salinities

Whole-body calcium uptake was studied in gilthead sea bream larvae (9–83·mg) in response to changing environmental salinity and [Ca2+]. Calcium uptake increased with increased fish size and salinity. Fish exposed to calcium-enriched, diluted seawater showed increased calcium uptake compared with fish in diluted seawater alone. Calcium uptake was unchanged in Na+- enriched, diluted seawater. Overall, [Ca2+], and not salinity/osmolarity per se, appears to be the main factor contributing to calcium uptake. By contrast, drinking was reduced by a decrease in salinity/osmolarity but was little affected by external [Ca2+]. Calculations of the maximum contribution from drinking-associated calcium uptake showed that it became almost insignificant (less than 10%) through a strong decrease in drinking rate at low salinities (0–8‰). Diluted seawater enriched in calcium to the concentration present in full-strength seawater (i.e. constant calcium, decreasing salinity) restored intestinal calcium uptake to normal. Extra-intestinal calcium uptake also benefited from calcium addition but to a lesser extent

Guiding of Rydberg atoms in a high-gradient magnetic guide

We study the guiding of $^{87}$Rb 59D$_{5/2}$ Rydberg atoms in a linear, high-gradient, two-wire magnetic guide. Time delayed microwave ionization and ion detection are used to probe the Rydberg atom motion. We observe guiding of Rydberg atoms over a period of 5 ms following excitation. The decay time of the guided atom signal is about five times that of the initial state. We attribute the lifetime increase to an initial phase of $l$-changing collisions and thermally induced Rydberg-Rydberg transitions. Detailed simulations of Rydberg atom guiding reproduce most experimental observations and offer insight into the internal-state evolution

Stream Network Geometry and the Spatial Influence of Aquatic Insect Subsidies Across the Contiguous United States

Emergent aquatic insects transport aquatic‐derived resources into terrestrial ecosystems but are rarely studied at landscape or regional scales. Here, we investigate how stream network geometry constrains the spatial influence of aquatic insect subsidies in terrestrial ecosystems. We also explore potential factors (i.e., climate, topography, soils, and vegetation) that could produce variation in stream network geometry and thus change the extent of aquatic insect subsidies from one region to another. The stream signature is the percentage of aquatic insect subsidies traveling a given distance into the terrestrial ecosystem, relative to what comes out of the stream. We use this concept to model the spatial extent (area) and distribution (spatial patterning) of aquatic subsidies in terrestrial ecosystems across the contiguous United States. Our findings suggest that at least 8% of the subsidies measured at the aquatic–terrestrial boundary (i.e., the 8% stream signature) are typically transferred throughout the entire watershed and that variation in this spatial extent is largely influenced by the drainage density of the stream network. Moreover, we found stream signatures from individual stream reaches overlap such that the spatial extent of the 8% stream signature often includes inputs from multiple stream reaches. Landscape‐scale stream network characteristics increased the area of overlapping stream signatures more than reach‐scale channel properties. Finally, we found runoff was an important factor influencing stream network geometry suggesting a potential effect of climate on aquatic‐to‐terrestrial linkages that have been understudied.Financial support was provided by a grant from this National Science Foundation (EF‐1802872) to DCA, and the Adams Family Endowment at the University of Oklahoma provided additional financial support to DAK. Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye

The Impact of the COVID 19 Pandemic on Stock Market Volatility: Evidence from a Selection of Developed and Emerging Stock Markets

This study examines the impact of the COVID 19 pandemic on the stock markets of China, India, Pakistan, the UK and the US using Generalised Autoregressive Conditional Heteroscedasticity (GARCH) and Threshold GARCH models with COVID 19 as an exogenous dummy variable in the variance equation. The sample period of 2016 – 2021 is divided into two sub-periods: the pre-COVID 19 period and the COVID 19 period. The results of the study indicate that the COVID 19 pandemic had a significant impact on the stock market volatility of the sample markets. Results from both the GARCH and Threshold GARCH models further confirm that there was persistent volatility in these markets and that this volatility increased as a result of the pandemic. In addition, the Threshold GARCH results indicate that the asymmetric term was significant in all markets indicating that bad news, such as the pandemic, had a stronger impact on the conditional variance of the returns as compared to good news. In addition, the results further confirm that the US market had no significant impact on the volatility of the Chinese market during the pandemic. The results have important implications for (i) international investors regarding portfolio management and investment risk minimisation in situations like the COVID 19 pandemic; and (ii) policymakers in terms of how they respond to any future pandemic