Stratospheric Effects on UV, Speed of Sound, Pressure, and Temperature

The atmosphere is composed of several layers, each with its own distinct environment varying in temperature, pressure, and levels of UV radiation. Quantifying these varying parameters proves to be useful in understanding atmospheric composition in greater detail. Variance in the composition of the atmosphere allows for the study of the evolution of physical phenomena at different altitudes. Our group quantified this variance using a high-altitude weather balloon and designed an experimental method to observe the nature of sound propagation through varying altitudes. The goal was to develop an altitude-dependent model of the speed of sound by using an open-air, microcontroller-based payload. Using our platform, we found that the open-air payload design results in noisy readings. Additionally, our method was restricted to low altitude environments, unable to produce reliable data above 6,700 meters. We address possible improvements and constraints in developing an open-air payload design to derive an altitude-dependent model for sound propagation. Furthermore, we present our findings on the variations in pressure, temperature, and levels of UV radiation during balloon flights at altitudes of up to 30,000 meters. These variations included a proportional decrease in pressure, a temperature inversion at 15,000 meters, and an exceptional increase in both UVA and UVB radiation as altitude increases

Transport, Growth, Decay and Sorption of Microorganisms and Nutrients through Porous Media: A Simulation with COMSOL

Abstract: Fate of microorganisms in porous media has very important applications in many branches of environmental and petroleum science and engineering, among others; however, concurrently it is a very complex and interacting phenomenon mainly because microorganisms are living. Applying the systematic modeling approach to continuum systems, we derive a model that include net flux of microorganisms and nutrients by convection and dispersion, growth and decay rates of microorganisms, chemotactic movement and nutrient consumption, adsorption of microorganisms and nutrients on rock grain surfaces, as well as desorption of microorganisms. Porosity reduction due to cell adsorption is considered. We use the Solute Transport application of the Earth Science Module in COMSOL Multiphysics to implement a numerical solution of the model. The numerical simulations reproduce results previously reported elsewhere; moreover, we show the spatial-temporal distribution of microorganisms and nutrients along the system and time. We point out the complementary role of the spatial-temporal distribution of components with breakthrough curves to analyze the behavior of both fluent and adsorbed components

Characterization of celotex and thermodynamic calculations of the formation of corrosion precursors on beryllium

The importance of safe and long-term storage of nuclear weapons components has drawn attention towards the characterization and understanding of the corrosion precursors formed on beryllium. A complete compositional and thermal characterization of celotex was carried out using energy dispersive spectroscopy, inductively coupled plasma-mass spectroscopic analysis, ion chromatography, and thermogravimetric analysis. Both fluoride and sulfate anions in addition to chloride as well as several metal ions are found to be present. The chloride present in celotex is lost at moderate temperatures 200 < T < 400 C, which may have important consequences on the formation of corrosion precursors. Equilibrium thermodynamic calculations on the stability of beryllium oxide in chlorinated environments were performed for a model system composed by beryllium, carbon, chlorine, hydrogen and oxygen. The calculations were aimed at describing the equilibrium, long-term behavior of a beryllium surface and its interaction with chlorine in a closed environment. The authors found that (i) carbon is essential for the formation of BeCl{sub 2}, and (ii) the chlorine-to-hydrogen ratio in chlorinated solvents is an important quantity since for solvents with chlorine-to-hydrogen ratio higher than 1, BeCl{sub 2} is not formed independently of the amount of solvent

Interventions to improve immigrant health. A scoping review.

Background: Disparities in health between immigrants and their host populations have been described across countries and continents. Hence, interventions for improving health targeting general populations are not necessarily effective for immigrants. Aims: To conduct a systematic search of the literature evaluating health interventions for immigrants; to map the characteristics of identified studies including range of interventions, immigrant populations and their host countries, clinical areas targeted and reported evaluations, challenges and limitations of the interventions identified. Following the results, to develop recommendations for research in the field. Methods: A scoping review approach was chosen to provide an overview of the type, extent and quantity of research available. Studies were included if they empirically evaluated health interventions targeting immigrants and/or their descendants, included a control group, and were published in English (PubMed and Embase from 1990 to 2015). Results: Most of the 83 studies included were conducted in the USA, encompassed few immigrant groups and used a randomized controlled trial (RCT) or cluster RCT design. Most interventions addressed chronic and non-communicable diseases and attendance at cancer screening services, used individual targeted approaches, targeted adult women and recruited participants from health centres. Outcome measures were often subjective, with the exception of interventions for cardiovascular risk and diabetes. Generally, authors claimed that interventions were beneficial, despite a number of reported limitations. Conclusions: Recommendations for enhancing interventions to improve immigrant health are provided to help researchers, funders and health care commissioners when deciding upon the scope, nature and design of future research in this area

Obesogenic Lifestyle and Its Influence on Adiposity in Children and Adolescents, Evidence from Mexico

Overweight (OW) and obesity (OB) during childhood/adolescence are major public health problems in Mexico. Several obesogenic lifestyle (OL) risk factors have been identified, but the burden and consequences of them in Mexican children/adolescents remain unclear. The objective of this study was to estimate the prevalence of OL components and describe their relationships with adiposity, and OW/OB. A population-based cross-sectional study of Mexican children/adolescents with nutritional assessment, data collection on daily habits and adiposity as fat-mass index (FMI) by dual-energy X-ray absorptiometry was performed. Individual OL-components: "inactivity," "excessive screen time," "insufficient sleep," "unhealthy-diet", were defined according to non-adherence to previously published healthy recommendations. RESULTS: 1449 subjects were assessed between March 2015 to April 2018. Sixteen percent of subjects had all four OL-components, 40% had three, 35% had two, 9% had one, and 0.5% had none. A cumulative OL score showed a significant dose-response effect with FMI. The combination of inactivity, excessive screen time, and insufficient sleep showed the highest risk association to OW/OB and higher values of FMI. CONCLUSIONS: The prevalence of OL-components was extremely high and associated with increased adiposity and OW/OB. Several interventions are needed to revert this major public health threat

Vasorelaxant activity of Euphorbia furcillata Kunth mainly by activation of NO/cGMP pathway and calcium channel blockade

The aim of current study was to determinate ex vivo and chromatographic fingerprint by HPLC of four extracts of Euphorbia furcillata K. Ethyl acetate extract of Euphorbia furcillata (EaEEf) was the most effective and potent extract (Emax=98.69±1.24%) and its effect was partially endothelium-dependent. Functional vasorelaxant mechanism of action of EaEEf was determinate, EaEEf showed efficient relaxation of KCl [80 mM]-induced contraction and norepinephrine and CaCl2 contraction curves showed diminution of maximal contraction in the presence of EAEEf and EaEEf-relaxation curve was shifted to the right in the presence of L-NAME (nitric oxide synthase inhibitor) and ODQ (guanylate cyclase inhibitor). Chromatographic fingerprints analysis suggests presence of diterpenoid such as abietane, tigliane, and ingenane skeletons. Our experiments suggest the EaEEf vasorelaxant activity could be attributed to diterpenoid molecules whose mechanism involves nitric oxide production and calcium channel blockade

First lunar outpost

Design and research efforts at the University of Puerto Rico have focused on the evaluation and refinement of the Habitability Criteria for a prolonged human presence in space during the last four years. Living quarters for a Mars mission and a third generation lunar base concept were proposed. This academic year, 1991-92, work on further refinement of the habitability criteria and design of partial gravity furniture was carried on. During the first semester, design alternatives for furniture necessary in a habitat design optimized for lunar and Martian environments were developed. Designs are based on recent research data from lunar and Mars gravity simulations, and current NASA standards. Artifacts will be submitted to NASA architects to be tested in KC-135 flights. Test findings will be submitted for incorporation in future updates to NASA habitat design standards. Second semester work was aimed at integrating these findings into the First Lunar Outpost (FLO), a mission scenario currently being considered by NASA. The mission consists of a manned return to the moon by crews of four astronauts for periods of 45 days. The major hardware components of the mission are as follows: (1) a Crew Module for the delivery of the crew and their supplies, and (2) the Habitat Module, which will arrive on the Moon unmanned. Our design efforts concentrated on this Habitat Module and on application of habitability criteria. Different geometries for the pressure vessel and their impact on the interior architecture were studied. Upon the selection of a geometry, a more detailed analysis of the interior design was performed, taking into consideration the reduced gravity, and the protection against radiation, micrometeorites, and the extreme temperature variation. A proposal for a FLO was submitted by the students, consisting essentially of a 24-feet (7.3 m.) by 35-feet (10.67 m) high vertical cylinder with work areas, crew quarters, galley, wardroom, leisure facilities, health maintenance, waste management, EVA operations facilities, and safe havens