Physical inactivity and its predictors among adolescents in Saudi Arabia: A cross-sectional comparison between cities with and without a Healthy Cities Program.

OBJECTIVES: To estimate the prevalence of insufficient physical activity and excessive screen time among adolescents living in cities participating in the Healthy Cities Program (HCP) and cities not running the program in the Qassim region of Saudi Arabia. METHODS: We surveyed 1133 adolescents from the Qassim region using systematic random sampling between April and September 2017. Multivariable logistic regression analyses were conducted to investigate the predictors of insufficient levels of PA and excessive screen time. RESULTS: The prevalence of <60 minutes of moderate- to vigorous-intensity physical activity/day was 82.4% and <3 days of vigorous intensity physical activity/week among adolescents was 59%. There was no significant association between living in healthy cities (HCPs) and insufficient levels of physical activity. The odds of excessive screen time were higher in HCPs than in cities not running the program (NHCPs) (OR: 1.49). The odds of insufficient daily PA (OR: 2.19) are higher among girls than boys. Increasing age is positively associated with insufficient weekly PA (OR: 1.19). The prevalence of excessive recreational screen time is 84.6% with higher odds in HCPs than in NHCPs (OR: 1.51). CONCLUSION: Our findings report a lack of evidence of any impact of the HCP on adolescents' physical activity behaviors. This outcome warrants a further in-depth evaluation of the process and outcomes of the HCP in Saudi Arabia

Exchange interaction effects in inter-Landau level Auger scattering in a two-dimensional electron gas

We consider the influence of spin effects on the inter-Landau level electron-electron scattering rate in a two-dimensional electron gas. Due to the exchange spin splitting, the Landau levels are not equidistant. This leads to the suppresion of Auger processes and a nonlinear dependence of the lifetime on the concentration of the excited electrons even at very low excitation levels.Comment: 10 pages, 3 figure

Analysis of line x environment interactions for yield in navy beans. 3. Pattern analysis of environments over years

Yield trials of navy bean (Phaseolus vulgaris L.) lines were grown over a diverse range of locations for 7 years in Queensland, with changes in entries and locations in each year. The yield data were analysed over years using 3 recently developed pattern analysis techniques for the integration of historical, severely unbalanced data from plant breeding programs to derive relationships among environments in the way they discriminate among the entries grown in them. These techniques have been named as cumulative analysis, sequential analysis, and status analysis. The relationships among the locations for testing navy bean lines, although sensitive to the addition of new locations, quickly stabilised. These relationships were related to management (irrigation and row width) and latitude (north v. central v. Kingaroy v. southern Queensland)

Interaction of surface acoustic waves with a two-dimensional electron gas in the presence of spin splitting of the Landau bands

The absorption and variation of the velocity of a surface acoustic wave of frequency $f$= 30 MHz interacting with two-dimensional electrons are investigated in GaAs/AlGaAs heterostructures with an electron density $n=(1.3 - 2.8) \times 10^{11} cm^{-2}$ at $T$=1.5 - 4.2 K in magnetic fields up to 7 T. Characteristic features associated with spin splitting of the Landau level are observed. The effective g factor and the width of the spin-split Landau bands are determined: $g^* \simeq 5$ and $A$=0.6 meV. The greater width of the orbital-split Landau bands (2 meV) relative to the spin-split bands is attributed to different shielding of the random fluctuation potential of charged impurities by 2D electrons. The mechanisms of the nonlinearities manifested in the dependence of the absorption and the velocity increment of the SAW on the SAW power in the presence of spin splitting of the Landau levels are investigated.Comment: Revtex 5 pages + 5 EPS Figures, v.2 - minor corrections in text and pic

Influence of Electrification Pathways in the Electricity Sector of Ethiopia—Policy Implications Linking Spatial Electrification Analysis and Medium to Long-Term Energy Planning

Ethiopia is a low-income country, with low electricity access (45%) and an inefficient power transmission network. The government aims to achieve universal access and become an electricity exporter in the region by 2025. This study provides an invaluable perspective on different aspects of Ethiopia’s energy transition, focusing on achieving universal access and covering the country’s electricity needs during 2015–2065. We co-developed and investigated three scenarios to examine the policy and technology levels available to the government to meet their national priorities. To conduct this analysis, we soft-linked OnSSET, a modelling tool used for geospatial analysis, with OSeMOSYS, a cost-optimization modelling tool used for medium to long-run energy planning. Our results show that the country needs to diversify its power generation system to achieve universal access and cover its future electricity needs by increasing its overall carbon dioxide emissions and fully exploit hydropower. With the aim of achieving universal access by 2025, the newly electrified population is supplied primarily by the grid (65%), followed by stand-alone (32%) technologies. Similarly, until 2065, most of the electrified people by 2025 will continue to be grid-connected (99%). The country’s exports will increase to 17 TWh by 2065, up from 832 GWh in 2015, leading to a cumulative rise in electricity export revenues of 184 billion USD

ApolipoproteinA1-75 G/A (M1-) polymorphism and Lipoprotein(a); Anti- vs. Pro-Atherogenic properties

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

"It's not rocket science" and "It's not brain surgery"-"It's a walk in the park": prospective comparative study

Objective: To compare cognitive testing scores in neurosurgeons and aerospace engineers to help settle the age old argument of which phrase—“It’s not brain surgery” or “It’s not rocket science”—is most deserved. // Design: International prospective comparative study. // Setting: United Kingdom, Europe, the United States, and Canada. // Participants: 748 people (600 aerospace engineers and 148 neurosurgeons). After data cleaning, 401 complete datasets were included in the final analysis (329 aerospace engineers and 72 neurosurgeons). // Main outcome: measures Validated online test (Cognitron’s Great British Intelligence Test) measuring distinct aspects of cognition, spanning planning and reasoning, working memory, attention, and emotion processing abilities. // Results: The neurosurgeons showed significantly higher scores than the aerospace engineers in semantic problem solving (difference 0.33, 95% confidence interval 0.13 to 0.52). Aerospace engineers showed significantly higher scores in mental manipulation and attention (−0.29, −0.48 to −0.09). No difference was found between groups in domain scores for memory (−0.18, −0.40 to 0.03), spatial problem solving (−0.19, −0.39 to 0.01), problem solving speed (0.03, −0.20 to 0.25), and memory recall speed (0.12, −0.10 to 0.35). When each group’s scores for the six domains were compared with those in the general population, only two differences were significant: the neurosurgeons’ problem solving speed was quicker (mean z score 0.24, 95% confidence interval 0.07 to 0.41) and their memory recall speed was slower (−0.19, −0.34 to −0.04). // Conclusions: In situations that do not require rapid problem solving, it might be more correct to use the phrase “It’s not brain surgery.” It is possible that both neurosurgeons and aerospace engineers are unnecessarily placed on a pedestal and that “It’s a walk in the park” or another phrase unrelated to careers might be more appropriate. Other specialties might deserve to be on that pedestal, and future work should aim to determine the most deserving profession

Acetonitrile cluster solvation in a cryogenic ethane-methane-propane liquid: Implications for Titan lake chemistry

The atmosphere of Titan, Saturn’s largest moon, exhibits interesting UV- and radiation-driven chemistry between nitrogen and methane, resulting in dipolar, nitrile-containing molecules. The assembly and subsequent solvation of such molecules in the alkane lakes and seas found on the moon’s surface are of particular interest for investigating the possibility of prebiotic chemistry in Titan’s hydrophobic seas. Here we characterize the solvation of acetonitrile, a product of Titan’s atmospheric radiation chemistry tentatively detected on Titan’s surface [H. B. Niemann et al., Nature 438, 779–784 (2005)], in an alkane mixture estimated to match a postulated composition of the smaller lakes during cycles of active drying and rewetting. Molecular dynamics simulations are employed to determine the potential of mean force of acetonitrile (CH_3CN) clusters moving from the alkane vapor into the bulk liquid. We find that the clusters prefer the alkane liquid to the vapor and do not dissociate in the bulk liquid. This opens up the possibility that acetonitrile-based microscopic polar chemistry may be possible in the otherwise nonpolar Titan lakes