Alcohol and Substance Abuse in Higher Education: Suggestions for Student Affairs Professionals

2 Table of Content

Influence of Topological Edge States on the Properties of Al/Bi2Se3/Al Hybrid Josephson Devices

In superconductor-topological insulator-superconductor hybrid junctions, the barrier edge states are expected to be protected against backscattering, to generate unconventional proximity effects, and, possibly, to signal the presence of Majorana fermions. The standards of proximity modes for these types of structures have to be settled for a neat identification of possible new entities. Through a systematic and complete set of measurements of the Josephson properties we find evidence of ballistic transport in coplanar Al-Bi2Se3-Al junctions that we attribute to a coherent transport through the topological edge state. The shunting effect of the bulk only influences the normal transport. This behavior, which can be considered to some extent universal, is fairly independent of the specific features of superconducting electrodes. A comparative study of Shubnikov - de Haas oscillations and Scanning Tunneling Spectroscopy gave an experimental signature compatible with a two dimensional electron transport channel with a Dirac dispersion relation. A reduction of the size of the Bi2Se3 flakes to the nanoscale is an unavoidable step to drive Josephson junctions in the proper regime to detect possible distinctive features of Majorana fermions.Comment: 11 pages, 14 figure

Establishment and characterization of three cell lines from Aedes triseriatus (Diptera : Culicidae)

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Nitrous oxide distribution and its origin in the central and eastern South Pacific Subtropical Gyre

The mechanisms of microbial nitrous oxide (N<sub>2</sub>O) production in the ocean have been the subject of many discussions in recent years. New isotopomeric tools can further refine our knowledge of N<sub>2</sub>O sources in natural environments. This study compares hydrographic, N<sub>2</sub>O concentration, and N<sub>2</sub>O isotopic and isotopomeric data from three stations along a coast-perpendicular transect in the South Pacific Ocean, extending from the center (Sts. GYR and EGY) of the subtropical oligotrophic gyre (~26° S; 114° W) to the upwelling zone (St. UPX) off the central Chilean coast (~34° S). Although AOU/N<sub>2</sub>O and NO<sub>3</sub><sup>−</sup> trends support the idea that most of the N<sub>2</sub>O (mainly from intermediate water (200–600 m)) comes from nitrification, N<sub>2</sub>O isotopomeric composition (intramolecular distribution of <sup>15</sup>N isotopes) expressed as SP (site preference of <sup>15</sup>N) shows low values (10 to 12permil) that could be attributed to the production through of microbial nitrifier denitrification (reduction of nitrite to N<sub>2</sub>O mediated by ammonium oxidizers). The coincidence of this SP signal with high – stability layer, where sinking organic particles can accumulate, suggests that N<sub>2</sub>O could be produced by nitrifier denitrification inside particles. It is postulated that deceleration of particles in the pycnocline can modify the advection - diffusion balance inside particles, allowing the accumulation of nitrite and O<sub>2</sub> depletion suitable for nitrifier denitrication. As lateral advection seems to be relatively insignificant in the gyre, in situ nitrifier denitrification could account for 40–50% of the N<sub>2</sub>O produced in this layer. In contrast, coastal upwelling system is characterized by O<sub>2</sub> deficient condition and some N deficit in a eutrophic system. Here, N<sub>2</sub>O accumulates up to 480% saturation, and isotopic and isotopomer signals show highly complex N<sub>2</sub>O production processes, which presumably reflect both the effect of nitrification and denitrification at low O<sub>2</sub> levels on N<sub>2</sub>O production, but net N<sub>2</sub>O consumption by denitrification was not observed

Reducing the impact of radioactivity on quantum circuits in a deep-underground facility

As quantum coherence times of superconducting circuits have increased from nanoseconds to hundreds of microseconds, they are currently one of the leading platforms for quantum information processing. However, coherence needs to further improve by orders of magnitude to reduce the prohibitive hardware overhead of current error correction schemes. Reaching this goal hinges on reducing the density of broken Cooper pairs, so-called quasiparticles. Here, we show that environmental radioactivity is a significant source of nonequilibrium quasiparticles. Moreover, ionizing radiation introduces time-correlated quasiparticle bursts in resonators on the same chip, further complicating quantum error correction. Operating in a deep-underground lead-shielded cryostat decreases the quasiparticle burst rate by a factor fifty and reduces dissipation up to a factor four, showcasing the importance of radiation abatement in future solid-state quantum hardware

Earthworm management in tropical agroecosystems

In agrosystem field experiments, earthworm inoculation did not impede depletion of soil organic stocks in most cases, in spite of increased carbon inputs through enhanced primary production. Slight evidence of soil organic matter (SOM) protection was found in poorly structured soil, such as a yam plot in Ivory Coast (soil sieved before experimentation), and a pasture plot on Martinique. Aggregation inherited from past earthworm activities probably maintains SOM protection after earthworms have disappeared ; longer term experiments are necessary to observe C dynamics after the disappearance of inherited earthworm structures. In two experiments with maize in Ivory Coast and Peru, the activity of earthworms led to a small increase in the incorporation of organic matter from surface mulch in the SOM. Most of the C incorporated into the SOM originated from root material, and earthworm activities only slightly modified this pattern. Earthworm activity had significant effects on the distribution of C among particle size fractions. The general trend was a depletion of large (greater than 50 micrometers) particles and an accumulation of small (less than 2 micrometers) particles. Nutrient depletion in low-input cropping systems was not impeded by earthworm activities ; at Yurimaguas, some signs of a better conservation of K were noted after 3 years in the traditional rotation. (Résumé d'auteur

Ethoxyfagaronine, a synthetic analogue of fagaronine that inhibits vascular endothelial growth factor-1, as a new anti-angiogeneic agent

Angiogenesis plays a pivotal role in tumorigenesis and also contributes to the pathogenesis of hematologic malignancies. A number of plant compounds have shown efficacy in preclinical and clinical studies and some of them possess an anti-angiogenic activity. Our present findings report anti-angiogenic activities of ethoxyfagaronine (etxfag), a synthetic derivative of fagaronine. Once determined the non-cytotoxic concentration of etxfag, we showed that the drug inhibits VEGF-induced angiogenesis in a Matrigel™ plug assay and suppresses ex vivo sprouting from VEGF-treated aortic rings. Each feature leading to neovascularization was then investigated and results demonstrate that etxfag prevents VEGF-induced migration and tube formation in human umbilical vein endothelial cells (HUVEC). Moreover, etxfag also suppresses VEGF-induced VEGFR-2 phosphorylation and inhibits FAK phosphorylation at Y-861 as well as focal adhesion complex turnover. Beside these effects, etxfag modifies MT1-MMP localization at the endothelial cell membrane. Finally, immunoprecipitation assay revealed that etxfag decreases VEGF binding to VEGFR-2. As we previously reported that etxfag is able to prevent leukemic cell invasiveness and adhesion to fibronectin, all together our data collectively support the anti-angiogenic activities of etxfag which could represent an additional approach to current anti-cancer therapies

Intermediate Tail Dependence: A Review and Some New Results

The concept of intermediate tail dependence is useful if one wants to quantify the degree of positive dependence in the tails when there is no strong evidence of presence of the usual tail dependence. We first review existing studies on intermediate tail dependence, and then we report new results to supplement the review. Intermediate tail dependence for elliptical, extreme value and Archimedean copulas are reviewed and further studied, respectively. For Archimedean copulas, we not only consider the frailty model but also the recently studied scale mixture model; for the latter, conditions leading to upper intermediate tail dependence are presented, and it provides a useful way to simulate copulas with desirable intermediate tail dependence structures.Comment: 25 pages, 1 figur

Correction of moisture effects on near infrared calibration for the analysis of phenol content in eucalyptus wood extracts

Les méthodes basées sur la spectroscopie proche infrarouge pour estimer les propriétés du bois sont sensibles aux variations des paramètres physiques (température, granulométrie. . . ). Le bois étant un matériau hygroscopique sensible, l'influence de l'humidité sur l'absorbance et l'étalonnage proche infrarouge a été étudiée afin de mieux considérer les possibilités d'applications dans des conditions réelles.Un étalonnage de référence de la quantité de polyphénols présents dans les extraits a été établi à partir de spectres d'une collection de bois d'hybrides d'Eucalyptus urophylla × E. grandis à humidité constante fixée. D'autres spectres ont été obtenus sur des échantillons de même provenance mais à 8 teneurs en eau couvrant une large plage de variation. L'influence de l'humidité sur l'absorbance proche infrarouge puis sur l'estimation par le modèle de référence a été analysée. / Methods based on near infrared spectroscopy used to assess wood properties are susceptible to variations in physical parameters (temperature, grain size, etc). As wood is a hygroscopically sensitive material, we studied the effects of moisure on near infrared absorbance and calibration to accurately determine the application potential of this technique under routine. A collection of Eucalyptus urophylla x E. grandis hybrid wood pieces were analysed to obtain reference calibration of polyphenol contents in wood extracts via NIR spectra acquired under constant moisture conditions.Others specimens from the same source were assessed to obtain spectra for eight moisture contents spanning a broad variation range. The effects of moisture on absorption and on estimates based on a reference model were analysed. An increase in moisture content prompteda rise in near infrared absorption over the entire spectrum and the water O-H absorption bands. The polyphenol content estimates obtained by assessing specimens against the reference calibration at variable moisture contents revealed prediction bias. Five correction methods were then tested on enhance the robustness relative to moisture. In-depth calibration and external parameter orthogonalization were found to be the most efficient methods for offsetting this factor

Évolution des comportements et des représentations sociales liés à la consommation de cannabis chez les adolescents. Résumé

La recherche, dont les résultats principaux sont décrits dans ce résumé, visait trois objectifs différents: a) mieux comprendre l'évolution de la consommation de substances durant l'adolescence; b) mesurer les représentations sociales, par rapport à la consommation, dans une population de consommateurs comparée à une population «tout-venant»; c) valider un instrument de dépistage de la consommation. L'échantillon, sur lequel porte l'observation du suivi, est représentatif d'une population de consommateurs de substances. Le suivi a été réalisé sur une période de quatre ans, l'âge des sujets variant entre 15 et 20 ans au moment du premier entretien. Pour l'évaluation des représentations sociales, une population «tout-venant» a été recrutée, afin de pouvoir comparer les attitudes et opinions des adolescents en relation avec la consommation. Enfin, pour la validation de l'instrument de screening, les deux populations, suivi et «tout-venant», ont été réunies