1000 resultados para 379.2


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We report the synthesis and the structural and magnetic characterization of two new compounds: dibromobis-(pdmp)copper(II), CuBr2C22H24N4 (1), and dichlorobis(pdmp)copper(II), CuCl2C22H24N4 (2), where pdmp = 1-phenyl-3,5-dimethylpyrazole. The structures were refined by full-matrix least-squares techniques to R1 = 0.0620 and 0.0777, respectively. Compound 1 belongs to the space group P21/n with a = 8.165(5) Å, b = 10.432(3) Å, c = 13.385(4) Å, β = 100.12(4)̊, and Z = 2. Compound 2 belongs to the space group P21/c with a = 8.379(2) Å, b = 22.630(2) Å, c = 12.256(2) Å, β= 98.43(3)°, and Z = 4. It has the same molecular formula as a compound reported previously but a different crystal structure. Detailed single-crystal EPR measurements were performed for single-crystal samples of 1 and 2 at 9 and 35 GHz and at room temperature. The positions and line widths of the EPR lines were measured as a function of the magnetic field orientation in three orthogonal planes. The data were used to study the electronic properties of the copper ions and to evaluate the exchange interactions between them. Our results are discussed in terms of the electronic pathways for superexchange between copper ions, which are provided by the stacking of pyrazole and phenyl rings of neighboring molecules and by hydrogen-halogen bonds. © 1999 American Chemical Society.

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Tässä väitöstutkimuksessa tutkittiin fysikaaliskemiallisten olosuhteiden ja toimintaparametrien vaikutusta juustoheran fraktiointiin. Kirjallisuusosassa on käsitelty heran ympäristövaikutusta, heran hyödyntämistä ja heran käsittelyä kalvotekniikalla. Kokeellinen osa on jaettu kahteen osaan, joista ensimmäinen käsittelee ultrasuodatusta ja toinen nanosuodatusta juustoheran fraktioinnissa. Ultrasuodatuskalvon valinta tehtiin perustuen kalvon cut-off lukuun, joka oli määritetty polyetyleeniglykoliliuoksilla olosuhteissa, joissa konsentraatiopolariosaatioei häiritse mittausta. Kriittisen vuon konseptia käytettiin sopivan proteiinikonsentraation löytämiseksi ultrasuodatuskokeisiin, koska heraproteiinit ovat tunnetusti kalvoa likaavia aineita. Ultrasuodatuskokeissa tutkittiin heran eri komponenttien suodattumista kalvon läpi ja siihen vaikuttavia ominaisuuksia. Herapermeaattien peptidifraktiot analysoitiin kokoekskluusiokromatografialla ja MALDI-TOF massaspektrometrillä. Kokeissa käytettävien nanosuodatuskalvojen keskimääräinen huokoskoko analysoitiin neutraaleilla liukoisilla aineilla ja zeta-potentiaalit virtauspotentiaalimittauksilla. Aminohappoja käytettiin malliaineina tutkittaessa huokoskoon ja varauksen merkitystä erotuksessa. Aminohappojen retentioon vaikuttivat pH ja liuoksen ionivahvuus sekä molekyylien väliset vuorovaikutukset. Heran ultrasuodatuksessa tuotettu permeaatti, joka sisälsi pieniä peptidejä, laktoosia ja suoloja, nanosuodatettiin happamassa ja emäksisessä pH:ssa. Emäksisissä oloissa tehdyssä nanosuodatuksessa foulaantumista tapahtui vähemmän ja permeaattivuo oli parempi. Emäksisissä oloissa myös selektiivisyys laktoosin erotuksessa peptideistä oli parempi verrattuna selektiivisyyteen happamissa oloissa.

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La reforma de los delitos contra la seguridad en el tráfico operada por LO 15/2007, de 30 de noviembre, constituye la expresión de un programa político-criminal de más amplio alcance, presente en el Proyecto de Reforma del Código Penal de 2007. En este trabajo se exponen las causas de la emergencia del nuevo derecho penal de la seguridad vial a la luz del paradi gma explicativo que ofrece el derecho penal postmoderno del riesgo -sometido aquí a necesarios ajustes- y se ofrece un análisis crítico de dos de los nuevos tipos: la conducción a velocidad por encima de determinados límites (art. 379.1) y la conducción con concentraciones de alcohol en aire espirado o en sangre superiores a determinadas tasas (0.6 mgr. o 1,2 gr. respectivamente) –art. 379.2-. Igualmente se analiza la propuesta del Proyecto de Reforma del Código de elevar a la categoría de delito las imprudencias leves con resultado de muerte. Tres piezas clave de un programa que trasluce una gran desconfianza hacia el estamento judicial y un optimismo infundado en las posibilidades del derecho penal para reducir eficazmente la siniestralidad vial.

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Lecture 5: Web 2.0 and Social Hypertext Contains Powerpoint Lecture slides and Hypertext Research Papers: What Is Web 2.0 Design Patterns and Business Models for the Next Generation of Software . Tim O'Reilly (2005); Web 2.0: Hypertext by Any Other Name? (Millard & Ross, 2006)

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El objetivo de esta investigación diagnostica radica en explicar los efectos de la implementación de la Revolución Educativa en las instituciones de Educación Media Técnica en la Provincia Centro del Departamento de Boyacá. Es así que se pretende demostrar si los procesos de implementación de articulación de la Institución Educativa Francisco de Paula Santander y la Institución Técnica Nacionalizada con el SENA, responden o no a las necesidades de los estudiantes frente a la coyuntura Nacional y Regional actual. Para lograr dicho fin, fue imperativo abordar esta problemática desde los siguientes enfoques: descriptivo, explicativo, analítico y propositivo; adicionalmente se realizaron encuestas a estudiantes, profesores y directivos de las Instituciones Educativas, de igual manera se llevaron a cabo una serie de entrevistas al Director Regional del SENA y al Secretario de Educación Departamental, como actores fundamentales del proceso. Permitiendo así formular posibles soluciones que apoyen la consolidación del proceso de articulación.

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El tema que explora este trabajo es la aplicación de las pruebas PISA en Colombia. Este criterio de evaluación creado por la Organización para la Cooperación y Desarrollo Económico (OCDE) es actualmente un estándar de calidad de educación a nivel internacional y diversos países lo han implementado como una forma para evaluar la calidad de prácticas políticas educativas que han desarrollado.La propuesta de este trabajo parte de la sospecha de que la preocupación por la aplicación de las pruebas PISA en Colombia tiene un interés más allá de darle solución al problema de la educación en el país. Desde una perspectiva de Relaciones Internacionales posible abordar la anterior sospecha, teniendo en cuenta que también existe otro componente adicional reiterativo en los discursos gubernamentales: la importancia del ingreso de Colombia a la OCDE como país miembro.

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Weathering of mine tailings in Adak results in high As concentrations in surface and ground water, sediments, and soil. In spite of the oxic conditions, As-rich surface and ground, water samples indicate As(III) species predominantly (up to 83%). Several microorganisms were isolated from the enrichment cultures that were involved in As cycling. Amongst them was Arsenicicoccus bolidensis - a novel gram-positive, facultatively anaerobic, coccus-shaped actinomycete, which actively reduced As(V) to As(III) in aqueous media. A. bolidensis reduced 0.06-0.20 mM day(-1) As(V). As(V) reduction displays a direct correlation between the initial As(V) concentration, growth rate, and biomass yield. (c) 2006 Elsevier B.V. All rights reserved.

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Pós-graduação em Agronomia (Energia na Agricultura) - FCA

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Objective Previous studies indicate that flexible footwear, which mimics the biomechanics of walking barefoot, results in decreased knee loads in patients with knee osteoarthritis (OA) during walking. However, the effect of flexible footwear on other activities of daily living, such as descending stairs, remains unclear. Our objective was to evaluate the influence of inexpensive and minimalist footwear (Moleca) on knee adduction moment (KAM) during stair descent of elderly women with and without knee OA. Methods. Thirty-four elderly women were equally divided into an OA group and a control group (CG). Stair descent was evaluated in barefoot condition, while wearing the Moleca, and while wearing heeled shoes. Kinematics and ground reaction forces were measured to calculate KAM by using inverse dynamics. Results. The OA group experienced a higher KAM during midstance under the barefoot condition (233.3%; P = 0.028), the Moleca (379.2%; P = 0.004), and heeled shoes (217.6%; P = 0.007). The OA group had a similar knee load during early, mid, and late stance with the Moleca compared with the barefoot condition. Heeled shoes increased the knee loads during the early-stance (versus barefoot [16.7%; P < 0.001] and versus the Moleca [15.5%; P < 0.001]), midstance (versus barefoot [8.6%; P = 0.014] and versus the Moleca [9.5%; P = 0.010]), and late-stance phase (versus barefoot [10.6%; P = 0.003] and versus the Moleca [9.2%; P < 0.001]). In the CG, the Moleca produced a knee load similar to the barefoot condition only during the early-stance phase. Conclusion. Besides the general foot protection, the inexpensive and minimalist footwear contributes to decreasing knee loads in elderly women with OA during stair descent. The loads are similar to the barefoot condition and effectively decreased when compared with heeled shoes.

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Briefwechsel zwischen Theodor W. Adorno, Gretel Adorno und Max Horkheimer, 1955-1957; Briefwechsel zwischen Alice Maier und Gertrud Straulino, 1957; 3 Briefe von Theodor W. Adorno und dem Soziologen Kurt H. Wolff, 1957; 1 Brief von Theodor W. Adorno und Herrn Hesse, 29.07.1957; 1 Brief von Theodor W. Adorno an Herbert Marcuse, 16.07.1957; 1 Brief von Theodor W. Adorno und dem Deutschen Institut für Talentstudien Köln, 03.07.1957; 1 Brief von Franz Ollig an Max Horkheimer, 10.04.1957; 1 Brief von H. Schelsky von der Deutschen Gesellschaft für Soziologie in Hamburg an Friedrich Bülow, 19.02.1957; 1 Rundbrief der Deutschen Gesellschaft für Soziologie in Hamburg; 1 Brief von Max Horkheimer und Theodor W. Adorno an Julius Ebbinghaus, 07.01.1957;

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Changes in intracellular Ca(2+) concentration ([Ca(2+)](i)) play a central role in neuronal differentiation. However, Ca(2+) signaling in this process remains poorly understood and it is unknown whether embryonic and adult stem cells share the same signaling pathways. To clarify this issue, neuronal differentiation was analyzed in two cell lines: embryonic P19 carcinoma stem cells (CSCs) and adult murine bone-marrow mesenchymal stem cells (MSC). We studied Ca(2+) release from the endoplasmic reticulum via intracellular ryanodine-sensitive (RyR) and IP(3)-sensitive (IP(3)R) receptors. We observed that caffeine, a RyR agonist, induced a [Ca(2+)](i) response that increased throughout neuronal differentiation. We also demonstrated a functional coupling between RyRs and L-but not with N-, P-, or Q-type Ca(v)1 Ca(2+) channels, both in embryonal CSC and adult MSC. We also found that agonists of L-type channels and of RyRs increase neurogenesis and neuronal differentiation, while antagonists of these channels have the opposite effect. Thus, our data demonstrate that in both cell lines RyRs control internal Ca(2+) release following voltage-dependent Ca(2+) entry via L-type Ca(2+) channels. This study shows that both in embryonal CSC and adult MSC [Ca(2+)](i) is controlled by a common pathway, indicating that coupling of L-type Ca(2+) channels and RyRs may be a conserved mechanism necessary for neuronal differentiation.

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Objectives: The aim of this study was to evaluate the fluoride intake of 2-6-year-old Brazilian children using a semiquantitative food frequency questionnaire (FFQ) which also estimated fluoride intake from dentifrice. Methods: The FFQ was previously validated through application to 78 2-6-year-old Brazilian children and then administered to 379 children residing in an optimally fluoridated community in Brazil (Bauru, State of Sao Paulo). The FFQ was applied to the parents and used to estimate the food intake of the children. The constituents of the diet were divided into solids, water and other beverages. The fluoride content of the diet items was analyzed with the fluoride electrode. The questionnaire also estimated fluoride intake from dentifrice. Results: The average (+/- SD) fluoride intake from solids, water, other beverages and dentifrice was 0.008 +/- 0.005; 0.011 +/- 0.004; 0.009 +/- 0.014 and 0.036 +/- 0.028 mg F/kg body weight/day, respectively, totalizing 0.064 +/- 0.035 mg F/kg body weight/day. The dentifrice and the diet contributed with 56.3% and 43.7% of the daily fluoride intake, respectively. Among the children evaluated, 31.2% are estimated to have risk to develop dental fluorosis (intake > 0.07 mg F/kg body weight/day). Conclusions: The dentifrice was the main source of fluoride intake by the children evaluated. However, the fluoride concentration in food items also significantly contributed to the daily ingestion by 2-6-year-old children. The questionnaire used seems to be a promising alternative to duplicate diet to estimate the fluoride intake at this age range and may have potential to be used in broad epidemiological surveys.