62 research outputs found

    Ni, Co and Ni-Co-Modified Tungsten Carbides Obtained by an Electric Arc Method as Dry Reforming Catalysts

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    075-15-2021-710. Research on the synthesis of tungsten carbide was supported by the RF Ministry of Education and Science project No FSWW-2022-0018Dry reforming of methane (DRM), to produce synthesis gas, is one of the most important chemical reactions used for the industrial production of hydrogen and leads to the synthesis of hydrocarbons (liquid fuels) and other valuable products. A cost-effective alternative to active and stable noble metal DRM catalysts, with comparable catalytic performance, can be composite materials based on nickel, cobalt and transition metal carbides. In this line, the present work proposes a non-standard way to obtain dry reforming catalysts of Ni, Co and Ni-Co-modified tungsten carbide (WC) produced by an electric arc method. Different amounts of nickel, cobalt and their mixtures were deposited on tungsten carbide by deposition-precipitation with NaOH (DP) and incipient wetness impregnation (IWI) methods. The resulting materials were characterized by N2 adsorption-desorption, transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy, and their performance was evaluated in DRM. The composition and preparation method of catalysts predetermined their structural, textural and electronic properties, playing a decisive role in their activity for DRM. DP-prepared 20%Ni/WC material remained resistant to oxidation, both that of the active metal (nickel) and of the tungsten carbide, as well as to coking during DRM. This sample proved to be the most active and stable among all studied materials. Possibly, the resistance to oxidation and coking was due to a more efficient implementation of the oxidation/(re)carbonization cycle on the surface of this catalyst.publishersversionpublishe

    Living with Diversity Vol. II: 20-21 October 2009, University of Ljubljana

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    Living with Diversity, volume II, documents the proceedings of the Slovenia-Japan University Cooperation Network Graduate Student Forum Series held at Ljubljana University in 2009. The proceedings comprise the individual research papers as well as reports of the two discussion sessions and overall forum evaluation. While the individual papers discuss issues from each researcher’s specific field of expertise within the federating theme, the discussion sessions address a wide range of issues and problems concerning the individual, governance and flexibility from an essentially trans-disciplinary perspective. 『多様性を生きる』第2巻は、2009年にリュブリャナ大学において開催された「スロベニア・日本学生知的交流会議」の報告書です。本報告書は、個々の論文ならびに2つのディスカッション・セッション報告と学生会議に対する総評を収めています。各論文においては、統一テーマの枠内で、研究者が各自の専門領域から問題を論じているのに対して、2つのディスカッション・セッションにおいては、本質的に領域横断的な視点から、個人、統治、柔軟性に関する広範な論点と課題を取り上げています

    Estado del arte de la quinua en el mundo en 2013

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    Alimento de base de las poblaciones andinas desde hace milenios, la quinua se ha convertido hoy en un producto apreciado en el mercado internacional de alimentos dietéticos, orgánicos y equitativos. Este cambio lo iniciaron los mismos productores del Altiplano Sur de Bolivia hace aproximadamente unos 40 años. En medio de un desierto de altura, ellos lograron desarrollar una floreciente producción agrícola de exportación. Aunque cuentan con lucrativos nichos de mercado, los productores de quinua no son agricultores especializados, ni residen de forma permanente en la zona de producción. Estas son algunas de las paradojas que caracterizan la producción de quinua en el Altiplano Sur de Bolivia. Después de describir el origen, la diversidad y los rasgos biológicos del ecotipo Quinua Real en el cual se basa la producción de esta zona, se plantea la importancia de la quinua en los agrosistemas locales y, más allá, en los sistemas de actividades agrícolas y no agrícolas manejados por las familias del Altiplano Sur. Movilidad geográfica y pluriactividad forman parte del modo de vida ancestral de estas poblaciones y determinan hasta hoy en día las condiciones de uso de los recursos territoriales y la organización de los productores en el contexto del auge comercial de la quinua. La producción actual de quinua en la región presenta rasgos de vulnerabilidad agroecológica y social, así como capacidades adaptativas para enfrentarlos. Se resaltan como puntos clave para la sostenibilidad de los agrosistemas locales : i) la concertación de reglas comunales e individuales para el acceso y uso de la tierra en agrosistemas socialmente equitativos y equilibrados entre cultivo y ganadería, ii) las normas internacionales para el reconocimiento de la Quinua Real en los mercados de exportación, iii) una actualización continua de las reglas y normas para mantener la adaptabilidad de los agrosistemas locales a los cambios imprevisibles del contexto socio-ecológico a varias escalas de espacio y de tiempo

    Practice Guidelines for Teledermatology

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    Previous American Telemedicine Association (ATA) Teledermatology Practice Guidelines were issued in 2007. This updated version reflects new knowledge in the field, new technologies, and the need to incorporate teledermatology practice in a variety of settings, including hospitals, urgent care centers, Federally Qualified Health Centers, school-based clinics, public health facilities, and patient homes.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140294/1/tmj.2016.0137.pd

    A cost minimisation analysis in teledermatology: model-based approach

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    <p>Abstract</p> <p>Background</p> <p>Although store-and-forward teledermatology is increasingly becoming popular, evidence on its effects on efficiency and costs is lacking. The aim of this study, performed in addition to a clustered randomised trial, was to investigate to what extent and under which conditions store-and-forward teledermatology can reduce costs from a societal perspective.</p> <p>Methods</p> <p>A cost minimisation study design (a model based approach) was applied to compare teledermatology and conventional process costs per dermatology patient care episode. Regarding the societal perspective, total mean costs of investment, general practitioner, dermatologists, out-of-pocket expenses and employer costs were calculated. Uncertainty analysis was performed using Monte Carlo simulation with 31 distributions in the used cost model. Scenario analysis was performed using one-way and two-way sensitivity analyses with the following variables: the patient travel distance to physician and dermatologist, the duration of teleconsultation activities, and the proportion of preventable consultations.</p> <p>Results</p> <p>Total mean costs of teledermatology process were €387 (95%CI, 281 to 502.5), while the total mean costs of conventional process costs were €354.0 (95%CI, 228.0 to 484.0). The total mean difference between the processes was €32.5 (95%CI, -29.0 to 74.7). Savings by teledermatology can be achieved if the distance to a dermatologist is larger (> = 75 km) or when more consultations (> = 37%) can be prevented due to teledermatology.</p> <p>Conclusions</p> <p>Teledermatology, when applied to all dermatology referrals, has a probability of 0.11 of being cost saving to society.</p> <p>In order to achieve cost savings by teledermatology, teledermatology should be applied in only those cases with a reasonable probability that a live consultation can be prevented.</p> <p>Trail Registration</p> <p>This study is performed partially based on PERFECT D Trial (Current Controlled Trials No.ISRCTN57478950).</p

    New genetic loci link adipose and insulin biology to body fat distribution.

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    Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

    Mitochondrial physiology

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    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders

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    Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyper-activity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.Peer reviewe
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