Best management practices for Nitrogen use in northwestern Minnesota

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Bulk single crystals and physical properties of β-(AlxGa1-x)2O3(x = 0-0.35) grown by the Czochralski method

We have systematically studied the growth, by the Czochralski method, and basic physical properties of a 2 cm and 2 in. diameter bulk β-(AlxGa1-x)2O3 single crystal with [Al] = 0-35 mol. % in the melt in 5 mol. % steps. The segregation coefficient of Al in the Ga2O3 melt of 1.1-1.2 results in a higher Al content in the crystals than in the melt. The crystals were also co-doped with Si or Mg. [Al] = 30 mol. % in the melt (33-36 mol. % in the crystals) seems to be a limit for obtaining bulk single crystals of high structural quality suitable for homoepitaxy. The crystals were either semiconducting (no intentional co-dopants with [Al] = 0-30 mol. % and Si-doped with [Al] = 15-20 mol. %), degenerately semiconducting (Si-doped with [Al] ≤ 15 mol. %), or semi-insulating ([Al] ≥ 25 mol. % and/or Mg-doped). The full width at half maximum of the rocking curve was 30-50 arcsec. The crystals showed a linear but anisotropic decrease in all lattice constants and a linear increase in the optical bandgap (5.6 eV for [Al] = 30 mol. %). The room temperature electron mobility at similar free electron concentrations gradually decreases with [Al], presumably due to enhanced scattering at phonons as the result of a larger lattice distortion. In Si co-doped crystals, the scattering is enhanced by ionized impurities. Measured electron mobilities and bandgaps enabled to estimate the Baliga figure of merit for electronic devices

Around the World, Adolescence Is a Time of Heightened Sensation Seeking and Immature Self-Regulation

The dual systems model of adolescent risk‐taking portrays the period as one characterized by a combination of heightened sensation seeking and still‐maturing self‐regulation, but most tests of this model have been conducted in the United States or Western Europe. In the present study, these propositions are tested in an international sample of more than 5000 individuals between ages 10 and 30 years from 11 countries in Africa, Asia, Europe and the Americas, using a multi‐method test battery that includes both self‐report and performance‐based measures of both constructs. Consistent with the dual systems model, sensation seeking increased between preadolescence and late adolescence, peaked at age 19, and declined thereafter, whereas self‐regulation increased steadily from preadolescence into young adulthood, reaching a plateau between ages 23 and 26. Although there were some variations in the magnitude of the observed age trends, the developmental patterns were largely similar across countries

Squeezing the Threshold of Metal‐Halide Perovskite Micro‐Crystal Lasers Grown by Solution Epitaxy

Metal halide perovskite semiconductors have demonstrated remarkable progress not only in photovoltaics and X‐ray detection but also in laser technologies. Particularly appealing is the simplicity with which micro‐crystallites can be epitaxially grown, thereby forming micro‐resonators suitable for lasing. Here, the laser threshold is optimized by selecting excitation laser parameters and by improving material quality. The latter process is conducted for formamidinium lead tribromide, emitting in the green spectral range. Depending on the growth method and parameters, the sizes of the micro‐resonators can be tuned between ≈3 and 23 micrometers. Under laser excitation systematically lower thresholds are observed for micro‐resonators in the 4–7 micrometer size range, than for larger ones, irrespective of growth method. Among three optimized growth methods, epitaxial growth via antisolvent vapor‐assisted crystallization exhibits the smallest threshold powers, indicating the highest material quality. This conclusion is supported by hyperspectral microscopic luminescence imaging and by transient photoluminescence. The best laser structures exhibit record threshold powers for epitaxially grown perovskites, indicating that the selected antisolvent vapor epitaxial growth holds great promises also for other perovskite materials.Perovskite microcrystal lasers with record low threshold powers are presented. This is achieved by improving solution epitaxial growth methods and pump laser parameters. Antisolvent vapor‐assisted crystallization epitaxy provides not only the best lasing performance, but also crystalline quality similar to that of the single‐crystal lead sulfide substrates. imageDeutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659Erlangen Graduate School in Advanced Optical Technologie

GA4GH: International policies and standards for data sharing across genomic research and healthcare.

The Global Alliance for Genomics and Health (GA4GH) aims to accelerate biomedical advances by enabling the responsible sharing of clinical and genomic data through both harmonized data aggregation and federated approaches. The decreasing cost of genomic sequencing (along with other genome-wide molecular assays) and increasing evidence of its clinical utility will soon drive the generation of sequence data from tens of millions of humans, with increasing levels of diversity. In this perspective, we present the GA4GH strategies for addressing the major challenges of this data revolution. We describe the GA4GH organization, which is fueled by the development efforts of eight Work Streams and informed by the needs of 24 Driver Projects and other key stakeholders. We present the GA4GH suite of secure, interoperable technical standards and policy frameworks and review the current status of standards, their relevance to key domains of research and clinical care, and future plans of GA4GH. Broad international participation in building, adopting, and deploying GA4GH standards and frameworks will catalyze an unprecedented effort in data sharing that will be critical to advancing genomic medicine and ensuring that all populations can access its benefits

The influence of groups and alcohol consumption on individual risk-taking

© 2017 Elsevier B.V. Background: Research addressing the influence of alcohol and groups on risky behaviour has yielded contradictory findings regarding the extent to which intoxicated groups exaggerate or minimise risk-taking. Previous work has examined the effect of intoxication on risk-taking focusing on collective group decision-making, and to date the influence of alcohol consumption and groups on individual risk-taking has yet to be explored experimentally. The current study therefore examined the impact of intoxication and groups on individual risk-taking. Methods In a mixed design, 99 social drinkers (62 female) attended an experimental session individually (N = 48) or in groups of three (N = 51). Individuals completed the study in isolation while groups were tested in the same room. Participants completed two behavioural measures of risk-taking: Balloon Analogue Risk Task (BART) and Stoplight Task (SLT), both before and following consumption of an alcoholic (0.6 g/kg males, 0.5 g/kg females) or a placebo beverage. Results Those who participated in groups took significantly more risks in both tasks than those in isolation. Alcohol did not increase risk-taking on either risk-taking tasks. However, those who consumed placebo were significantly less risky on the SLT, compared to baseline. No interactions were found between context and beverage on risk-taking. Conclusion The findings do not support a combined effect of alcohol and groups on individual risk-taking. Rather, results indicate that risk-taking behaviour is influenced by peer presence regardless of alcohol consumption. Targeting the influence of groups (above those of alcohol) may hold promise for reducing risk-taking behaviours in drinking environments