Noncentrosymmetric Tetrel Pnictides RuSi4P4 and IrSi3P3: Nonlinear Optical Materials with Outstanding Laser Damage Threshold

Noncentrosymmetric (NCS) tetrel pnictides have recently generated interest as nonlinear optical (NLO) materials due to their second harmonic generation (SHG) activity and large laser damage threshold (LDT). Herein nonmetal-rich silicon phosphides RuSi₄P₄ and IrSi₃P₃ are synthesized and characterized. Their crystal structures are reinvestigated using single crystal X-ray diffraction and ²⁹Si and ³¹P magic angle spinning NMR. In agreement with previous report RuSi₄P₄ crystallizes in NCS space group P1, while IrSi₃P₃ is found to crystallize in NCS space group Cm, in contrast with the previously reported space group C2. A combination of DFT calculations and diffuse reflectance measurements reveals RuSi₄P₄ and IrSi₃P₃ to be wide bandgap (E_g) semiconductors, E_g = 1.9 and 1.8 eV, respectively. RuSi₄P₄ and IrSi₃P₃ outperform the current state-of-the-art infrared SHG material, AgGaS₂, both in SHG activity and laser inducer damage threshold. Due to the combination of high thermal stabilities (up to 1373 K), wide bandgaps (≈2 eV), NCS crystal structures, strong SHG responses, and large LDT values, RuSi₄P₄ and IrSi₃P₃ are promising candidates for longer wavelength NLO materials.     

Adoption and usage of Academic Social Networks: a Japan case study

Scientometrics - Engaging in the international academic environment is now facilitated by a range of Academic Social Networks (ASNs) that are being used by an increasing number of early career and...     

Does life satisfaction moderate the effects of stressful life events on psychopathological behavior during adolescence?

Psychologists within a positive psychology framework have proposed the existence of a set of psychological strengths that buffer against the development of psychopathology. To date, most research efforts in positive psychology have focused on adults. This longitudinal study tested the prediction that adolescents' judgments of life satisfaction moderate the influence of stressful life events on the subsequent development of psychopathological behavior. Using a sample of 816 middle and high school students, the study demonstrated support for the moderational model for externalizing behavior outcomes, but not internalizing behavior problems. Specifically, adolescents with positive life satisfaction (vs. those who were dissatisfied with their lives) were less likely to develop later externalizing behaviors in the face of stressful life events. The study also revealed that adolescent life satisfaction reports show moderate stability across a one-year time frame and independently predict subsequent externalizing behavior even while controlling for prior levels of externalizing behavior... (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Breath and blood ethanol following use of a cough-cold preparation

All leaders in health care today are charged with the responsibility of transforming present practices into new and different ones that are needed for the future. The structural side of transforming is ultimately easier than the human side. However, the most frequent failures come from not concentrating sufficiently on the behavioral side of the change. Structural and psychological change must occur simultaneously and embrace each other for best results.     

The application of multivariat mathematical-statistical methods to the solution of problems in nutrition theory,nutritional economics and food technology Part 4. Optimization with n ≥ 2 effect variables

The milling industry faces the task of saving energy without impairing the quantity and quality of the products. By applying experimental plans for the optimization of several effect variables, approximations (compromise solutions) between the cause variables (conditioning parameters) and the effect variables (quantity and quality parameters) are sought, which satisfy the aims laid down.     

Amorphous chromium silicide formation in hydrogenated amorphous silicon

The interaction between thin films of hydrogenated amorphous silicon and sputter-deposited chromium has been studied. Following deposition of the chromium films at room temperature, the films were annealed over a range of times and temperatures below 350°C. It was found that an amorphous silicide was formed only a few nanometers thick with the square of thickness proportional to the annealing time. The activation energy for the process was 0.55±0.05 eV. The formation process of the silicide was very reproducible with the value of density derived from the thickness and Cr surface density being close to the value for crystalline CrSi₂ for all films formed at temperatures ≤300°C. The specific resistivity of the amorphous CrSi₂ was ≈600 μΩ·cm and independent of annealing temperature.     

Knowledge conceptualization tool

Knowledge acquisition is one of the most important and problematic aspects of developing knowledge-based systems. Many automated tools have been introduced in the past, however, manual techniques are still heavily used. Interviewing is one of the most commonly used manual techniques for a knowledge acquisition process, and few automated support tools exist to help knowledge engineers enhance their performance. The paper presents a knowledge conceptualization tool (KCT) in which the knowledge engineer can effectively retrieve, structure, and formalize knowledge components, so that the resulting knowledge base is accurate and complete. The KCT uses information retrieval technique to facilitate conceptualization, which is one of the human intensive activities of knowledge acquisition. Two information retrieval techniques employing best-match strategies are used: vector space model and probabilistic ranking principle model. A prototype of the KCT was implemented to demonstrate the concept. The results from KCT are compared with the outputs from a manual knowledge acquisition process in terms of amount of information retrieved and the process time spent. An analysis of the results shows that the process time to retrieve knowledge components (e.g., facts, rules, protocols, and uncertainty) of KCT is about half that of the manual process, and the number of knowledge components retrieved from knowledge acquisition activities is four times more than that retrieved through a manual process