888 resultados para Search of Optimal Paths


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Background: Although the health benefits of physical activity are well-established, the evidence regarding the efficacy of physical activity counseling by primary care providers is inconclusive. Healthy People 2020 recommends that physicians provide counseling on physical activity to their patients; however, few providers adhere to these guidelines. The primary objective of this review is to systematically summarize and evaluate primary care providers' perceptions and attitudes about physical activity counseling. ^ Methods: A systematic literature search of relevant articles was conducted between January and May 2011 using four databases: MEDLINE (1948 to the present), PsycInfo (1806 to the present), CINAHL Plus with Full Text (1981 to the present), and the Cochrane Library. Studies were included if 1) the study population consisted of primary care providers and, 2) the study evaluated providers' attitudes and perceptions pertaining to physical activity counseling. Both quantitative and studies were considered. ^ Results: Most primary care providers agree that physical activity counseling is important and that they have a role in promoting physical activity to their patients. Providers are uncertain about the effectiveness of counseling, feel only marginally comfortable providing more than general advice about physical activity, and cite major barriers to counseling such as lack of time, lack of training, and lack of reimbursement for their counseling efforts. The evidence in this review suggests that beyond these barriers, providers are more likely to counsel their patients about physical activity if they are active themselves, or if they feel that their patients' condition, such as cardiovascular disease or obesity, would strongly benefit from a lifestyle change. ^ Conclusion: While major barriers to physical activity counseling, such as lack of time for counseling and lack of counseling knowledge still exist, primary care providers are receptive to the idea of acting as physical activity promoters in their clinical practices. However, the barriers encountered need to be addressed on multiple levels (e.g. individual, organizational), and additional training is needed in order for providers to effectively promote the physical activity of their patients.^

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Background: An increased understanding of the pathogenesis of cancer at the molecular level has led to the development of personalized cancer therapy based on the mutation status of the tumor. Tailoring treatments to genetic signatures has improved treatment outcomes in patients with advanced cancer. We conducted a meta-analysis to provide a quantitative summary of the response to treatment on a phase I clinical trial matched to molecular aberration in patients with advanced solid tumors. ^ Methods: Original studies that reported the results of phase I clinical trials in patients with advanced cancer treated with matched anti-cancer therapies between January 2006 and November 2011 were identified through an extensive search of Medline, Embase, Web of Science and Cochrane Library databases. Odds Ratio (OR) with 95% confidence interval (CI) was estimated for each study to assess the strength of an association between objective response rate (ORR) and mutation status. Random effects model was used to estimate the pooled OR and their 95% CI was derived. Funnel plot was used to assess publication bias. ^ Results: Thirteen studies published between January 2006 and November 2011that reported on responses to matched phase I clinical trials in patients with advanced cancer were included in the meta-analysis. Nine studies reported on the responses seen in 538 of the 835 patients with driver mutations responsive to therapy and seven studies on the responses observed in 234 of the 306 patients with mutation predictive for negative response. Random effects model was used to estimate pooled OR, which was 7.767(95% CI = 4.199 − 14.366; p-value=0.000) in patients with activating mutations that were responsive to therapy and 0.287 (95% CI = 0.119 − 0.694; p-value=0.009) in patients with mutation predictive of negative response. ^ Conclusion: It is evident from the meta-analysis that somatic mutations present in tumor tissue of patients are predictive of responses to therapy in patients with advanced cancer in phase I setting. Plethora of research and growing evidence base indicate that selection of patients based on mutation analysis of the tumor and personalizing therapy is a step forward in the war against cancer.^

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Studies suggest that slim infants (low weight-for-height) experienced higher mortality rates than average or high weight-for-height infants (Miller and Hassanein, 1973; Hoffman, Meirik, and Bakketeig, 1984). In this study, the 1980 National Natality Survey and the National Fetal Mortality Survey were used to examine the association of weight, height and perinatal mortality. All singleton births to white married mothers, between 18 and 34 years of age and of parity less than 4, for whom both mother's and hospital questionnaires were completed in those two surveys (3796 live births and 2043 fetal deaths) were selected for analysis. Overall, low weight and height infants had excess mortality rates. However, after adjustment for low birthweight and preterm birth status, low weight and height infants had only slightly higher mortality rates than their medium or high weight and height counterparts. The current study consists of relatively well-educated white married mothers of optimal reproductive age and low parity. Therefore, lower than expected mortality rates for slim infants may be attributed to these favorable demographic factors in this sample as compared with previous studies, or because of advances in perinatal medicine, slim infants may be prevented from achieving the high mortality seen in earlier studies. ^

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The Two State model describes how drugs activate receptors by inducing or supporting a conformational change in the receptor from “off” to “on”. The beta 2 adrenergic receptor system is the model system which was used to formalize the concept of two states, and the mechanism of hormone agonist stimulation of this receptor is similar to ligand activation of other seven transmembrane receptors. Hormone binding to beta 2 adrenergic receptors stimulates the intracellular production of cyclic adenosine monophosphate (cAMP), which is mediated through the stimulatory guanyl nucleotide binding protein (Gs) interacting with the membrane bound enzyme adenylylcyclase (AC). ^ The effects of cAMP include protein phosphorylation, metabolic regulation and transcriptional regulation. The beta 2 adrenergic receptor system is the most well known of its family of G protein coupled receptors. Ligands have been scrutinized extensively in search of more effective therapeutic agents at this receptor as well as for insight into the biochemical mechanism of receptor activation. Hormone binding to receptor is thought to induce a conformational change in the receptor that increases its affinity for inactive Gs, catalyzes the release of GDP and subsequent binding of GTP and activation of Gs. ^ However, some beta 2 ligands are more efficient at this transformation than others, and the underlying mechanism for this drug specificity is not fully understood. The central problem in pharmacology is the characterization of drugs in their effect on physiological systems, and consequently, the search for a rational scale of drug effectiveness has been the effort of many investigators, which continues to the present time as models are proposed, tested and modified. ^ The major results of this thesis show that for many b2 -adrenergic ligands, the Two State model is quite adequate to explain their activity, but dobutamine (+/−3,4-dihydroxy-N-[3-(4-hydroxyphenyl)-1-methylpropyl]- b -phenethylamine) fails to conform to the predictions of the Two State model. It is a weak partial agonist, but it forms a large amount of high affinity complexes, and these complexes are formed at low concentrations much better than at higher concentrations. Finally, dobutamine causes the beta 2 adrenergic receptor to form high affinity complexes at a much faster rate than can be accounted for by its low efficiency activating AC. Because the Two State model fails to predict the activity of dobutamine in three different ways, it has been disproven in its strictest form. ^

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This prospective cohort study estimated how antibacterial resistance affected the time until clinical response. Relative rates of improvement and cure were estimated by proportional-hazards regression for 391 patients with culture-confirmed bacterial keratitis who had the ciprofloxacin minimal inhibitory concentration (MIC) measured of the principal corneal isolate and who were treated with ciprofloxacin 0.3% solution or ointment. After adjusting for age and hypopyon status and stratifying by ulcer size, clinic, and ciprofloxacin formulation, the summary rate of clinical improvement with ciprofloxacin therapy was reduced by 42% (95% confidence limits [CL], 3%, 65%) among patients whose corneal isolate's ciprofloxacin MIC exceeded 1.0 μg/mL compared to those with more sensitive isolates. The summary rate of resolution to improvement and cure was reduced by 36% (95% CL, 11%, 53%) among corneal infections having a higher ciprofloxacin MIC. Rate ratios were modified by the size of the presenting corneal ulceration; for ulcer diameters of 4 mm or less and of more than 4 mm, improvement rate ratios were 0.56 (95% CL, 0.31, 1.02) and 0.65 (95% CL, 0.23, 1.80), respectively; resolution rate ratios were 0.63 (95% CL, 0.44, 0.91) and 0.67 (95% CL, 0.32, 1.39), respectively. Sensitivity analysis showed that the summary improvement rate ratio could be maximally overestimated by 24% (95% CL, −29%, 114%) because of informative censoring or by 33% (95% CL, −21%, 126%) from loss to follow up. Based on reported corneal pharmacokinetics of topical ciprofloxacin, the probability of clinical improvement was 90% or more if the ratio of the achievable corneal ciprofloxacin concentration to the corneal isolate's ciprofloxacin MIC was above 8 or the ratio of the area under the 24-hour corneal concentration curve to the ciprofloxacin MIC was greater than 151. This study suggests that corneal infections by bacteria having a higher ciprofloxacin MIC respond more slowly to ciprofloxacin treatment than those with a lower MIC. While the rate of clinical resolution is affected by patient age and clinical severity, antimicrobial susceptibility testing of corneal cultures can indicate the relative effectiveness of antibacterial therapy. A pharmacodynamic approach to treating bacterial keratitis offers the prospect of optimal antimicrobial selection and modification. ^

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In search of a meaningful stress indicator for Fucus vesiculosus we found that the often used quantitative determination procedures for the polysaccharide laminarin (beta-1,3-glucan) result in different kind of problems, uncertainties and limitations. This chemical long-term storage form of carbon enables perennial brown algae in seasonally fluctuating ecosystems to uncouple growth from photosynthesis. Because of this high ecological relevance a reliable and precise method for determination and quantification of laminarin is needed. Therefore, a simple, cold water extraction method coupled to a new quantitative liquid chromatography-mass spectrometrical method (LC-MS) was developed. Laminarin was determined in nine out of twelve brown algal species, and its expected typical molar mass distribution of 2000-7000 Da was confirmed. Furthermore, laminarin consisted of a complex mixture of different chemical forms, since fifteen chemical laminarin species with distinct molecular weights were measured in nine species of brown algae. Laminarin concentrations in the algal tissues ranged from 0.03 to 0.86% dry weight (DW). The direct chemical characterization and quantification of laminarin by LC-MS represents a powerful method to verify the biochemical and ecological importance of laminarin for brown algae. Single individuals of Laminaria hyperborea, L. digitata, Saccharina latissima, F. serratus, F. vesiculosus, F. spiralis, Himanthalia elongata, Cystoseira tamariscifolia, Pelvetia canaliculata, Ascophyllum nodosum, Halidrys siliquosa and Dictyota dichotoma were collected in fall (18.11.2013) during spring low tide from the shore of Finavarra, Co. Clare, west coast of Ireland (53° 09' 25'' N, 09° 06' 58'' W). After sampling, the different algae were immediately transported to the lab, lyophilized and sent to the University of Rostock. Laminarin was extracted with cold ultrapure water from the algal samples. Before extraction they were ground to < 1 mm grain size with an analytical mill (Ika MF 10 Basic). The algal material (approx. 1.5 g DW) was extracted in ultrapure water (8 mL) on a shaker (250 rpm) for 5 h. After the addition of surplus ultrapure water (4 mL) and shaking manually, 1 mL of the sample was filter centrifuged (45 µm) at 14,000 rpm (Hettich Mikro 22 R). The slightly viscous supernatant was free of suspended material and converted into a microvial (300 µL) for further analysis. The extracts were analyzed using liquid chromatography-mass spectrometry (LC-MS) analysis (LTQ Velos Pro ion trap spectrometer with Accela HPLC, Thermo Scientific). Laminarin species were separated on a KinetexTM column (2.6 µm C18, 150 x 3 mm). The mobile phase was 90 % ultrapure water and 10 % acetonitrile, run isocratically at a flow rate of 0.2 mL min-1. MS was working in ESI negative ion mode in a mass range of 100 - 4000 amu. Glucose contents were determined after extraction using high-performance liquid chromatography (HPLC). Extracted samples were analyzed in an HPLC (SmartLine, Knauer GmbH) equipped with a SUPELCOGELTM Ca column (30 x 7,8 mm without preColumn) and RI-detector (S2300 PDA S2800). Water was used as eluent at a flow rate of 0.8 mL min-1 at 75 °C. Glucose was quantified by comparison of the retention time and peak area with standard solutions using ChromGate software. Mannitol was extracted from three subsamples of 10-20 mg powdered alga material (L. hyperborea, L. digitata, S. latissima, F. serratus, F. vesiculosus, F. spiralis, H. elongata, P. canaliculata, A. nodosum, H. siliquosa) and quantified, following the HPLC method described by Karsten et al. (1991). For analyzing carbon and nitrogen contents, dried algal material was ground to powder and three subsamples of 2 mg from each alga thalli were loaded and packed into tin cartridges (6×6×12 mm). The packages were combusted at 950 °C and the absolute contents of C and N were automatically quantified in an elemental analyzer (Elementar Vario EL III, Germany) using acetanilide as standard according to Verardo et al. (1990).

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El propósito del presente trabajo es reconocer, cómo a partir de las tensiones globales y locales, de carácter socio - espacial e imbricadas en el proceso de metropolización que acusa el ámbito expandido de la ciudad de Paraná, es factible identificar y analizar los criterios básicos para proyectar una inédita gestión metropolitana dentro del espacio regional que constituyen tanto el ejido de la capital de la Provincia de Entre Ríos como el de sus tres municipios conurbados. En consecuencia y a tal fin, se intenta aquí establecer los nuevos desafíos incorporados a la gestión urbano-ambiental, tanto provincial como municipal, dentro de los que se platea articular la intervención estatal y la participación comunitaria, en el marco de un proceso de ordenamiento territorial del ámbito metropolizado en esas cuatro jurisdicciones en las que hoy habitan más de trescientos mil comprovincianos. Se trata, por tanto, de un proyecto estratégico que institucionalmente persiga la posibilidad de articular en simultáneo cuatro criterios políticos considerados aquí básicos para la gestión democrática del territorio metropolitano: la gobernabilidad, la competitividad, la sustentabilidad y la inclusión social. Criterios que, dentro de esa inteligencia, guiarán el análisis desarrollado sobre propuestas de actuación, jurídico-normativas y de gestión para abordar la compleja problemática del espacio urbano-regional. Es en tal contexto entonces, y dentro de esos principios primordiales para la intervención urbano-territorial, en el que se estima posible plantear, desde el ámbito institucional del Gobierno de la Provincia y de los gobiernos municipales, un acotado y preciso conjunto de políticas sectoriales básicas de ordenamiento que habiliten al despliegue de estrategias comunes y de consenso social posible, destinadas a transformar las críticas condiciones por las que atraviesa la conurbación en su conjunto, sin por eso vulnerar la autonomía de la jurisdicciones municipales incluidas en el espacio geográfico. Concluyendo, en el presente trabajo se analizan e identifican en forma iniciática, los criterios esenciales para el logro de los objetivos territoriales y las metas institucionales que dentro de la gestión metropolitana, puedan asumir el Estado Provincial y las jurisdicciones municipales, en tanto dispositivos gubernamentales destinados a que legal y orgánicamente, sean orientadas las políticas que tengan el propósito de afrontar tanto los procesos territoriales distorsivos como los déficit, las asimetrías y las carencias socio-ambientales que acusa la población del Gran Paraná

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La búsqueda de información y sus problemas colaterales inciden en el desarrollo de la actividad de los investigadores. Nos proponemos analizar esta temática a través del estudio de las pautas de comportamiento de investigadores de la Facultad de Humanidades y Ciencias de la Educación de la Universidad de La Plata, para identificar conductas informativas y al mismo tiempo detectar obstáculos que impiden el aprovechamiento óptimo de la Biblioteca Central y las Bibliotecas Departamentales de la Institución. Los resultados obtenidos servirán de base para definir indicadores de calidad aplicables a la mejora continua de los servicios de biblioteca. Como resultado del análisis de metodologías aplicadas en estudios de usuarios se determinó combinar las perspectivas cuantitativa y cualitativa en este trabajo en curso

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La búsqueda de información y sus problemas colaterales inciden en el desarrollo de la actividad de los investigadores. Nos proponemos analizar esta temática a través del estudio de las pautas de comportamiento de investigadores de la Facultad de Humanidades y Ciencias de la Educación de la Universidad de La Plata, para identificar conductas informativas y al mismo tiempo detectar obstáculos que impiden el aprovechamiento óptimo de la Biblioteca Central y las Bibliotecas Departamentales de la Institución. Los resultados obtenidos servirán de base para definir indicadores de calidad aplicables a la mejora continua de los servicios de biblioteca. Como resultado del análisis de metodologías aplicadas en estudios de usuarios se determinó combinar las perspectivas cuantitativa y cualitativa en este trabajo en curso

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El propósito del presente trabajo es reconocer, cómo a partir de las tensiones globales y locales, de carácter socio - espacial e imbricadas en el proceso de metropolización que acusa el ámbito expandido de la ciudad de Paraná, es factible identificar y analizar los criterios básicos para proyectar una inédita gestión metropolitana dentro del espacio regional que constituyen tanto el ejido de la capital de la Provincia de Entre Ríos como el de sus tres municipios conurbados. En consecuencia y a tal fin, se intenta aquí establecer los nuevos desafíos incorporados a la gestión urbano-ambiental, tanto provincial como municipal, dentro de los que se platea articular la intervención estatal y la participación comunitaria, en el marco de un proceso de ordenamiento territorial del ámbito metropolizado en esas cuatro jurisdicciones en las que hoy habitan más de trescientos mil comprovincianos. Se trata, por tanto, de un proyecto estratégico que institucionalmente persiga la posibilidad de articular en simultáneo cuatro criterios políticos considerados aquí básicos para la gestión democrática del territorio metropolitano: la gobernabilidad, la competitividad, la sustentabilidad y la inclusión social. Criterios que, dentro de esa inteligencia, guiarán el análisis desarrollado sobre propuestas de actuación, jurídico-normativas y de gestión para abordar la compleja problemática del espacio urbano-regional. Es en tal contexto entonces, y dentro de esos principios primordiales para la intervención urbano-territorial, en el que se estima posible plantear, desde el ámbito institucional del Gobierno de la Provincia y de los gobiernos municipales, un acotado y preciso conjunto de políticas sectoriales básicas de ordenamiento que habiliten al despliegue de estrategias comunes y de consenso social posible, destinadas a transformar las críticas condiciones por las que atraviesa la conurbación en su conjunto, sin por eso vulnerar la autonomía de la jurisdicciones municipales incluidas en el espacio geográfico. Concluyendo, en el presente trabajo se analizan e identifican en forma iniciática, los criterios esenciales para el logro de los objetivos territoriales y las metas institucionales que dentro de la gestión metropolitana, puedan asumir el Estado Provincial y las jurisdicciones municipales, en tanto dispositivos gubernamentales destinados a que legal y orgánicamente, sean orientadas las políticas que tengan el propósito de afrontar tanto los procesos territoriales distorsivos como los déficit, las asimetrías y las carencias socio-ambientales que acusa la población del Gran Paraná

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El propósito del presente trabajo es reconocer, cómo a partir de las tensiones globales y locales, de carácter socio - espacial e imbricadas en el proceso de metropolización que acusa el ámbito expandido de la ciudad de Paraná, es factible identificar y analizar los criterios básicos para proyectar una inédita gestión metropolitana dentro del espacio regional que constituyen tanto el ejido de la capital de la Provincia de Entre Ríos como el de sus tres municipios conurbados. En consecuencia y a tal fin, se intenta aquí establecer los nuevos desafíos incorporados a la gestión urbano-ambiental, tanto provincial como municipal, dentro de los que se platea articular la intervención estatal y la participación comunitaria, en el marco de un proceso de ordenamiento territorial del ámbito metropolizado en esas cuatro jurisdicciones en las que hoy habitan más de trescientos mil comprovincianos. Se trata, por tanto, de un proyecto estratégico que institucionalmente persiga la posibilidad de articular en simultáneo cuatro criterios políticos considerados aquí básicos para la gestión democrática del territorio metropolitano: la gobernabilidad, la competitividad, la sustentabilidad y la inclusión social. Criterios que, dentro de esa inteligencia, guiarán el análisis desarrollado sobre propuestas de actuación, jurídico-normativas y de gestión para abordar la compleja problemática del espacio urbano-regional. Es en tal contexto entonces, y dentro de esos principios primordiales para la intervención urbano-territorial, en el que se estima posible plantear, desde el ámbito institucional del Gobierno de la Provincia y de los gobiernos municipales, un acotado y preciso conjunto de políticas sectoriales básicas de ordenamiento que habiliten al despliegue de estrategias comunes y de consenso social posible, destinadas a transformar las críticas condiciones por las que atraviesa la conurbación en su conjunto, sin por eso vulnerar la autonomía de la jurisdicciones municipales incluidas en el espacio geográfico. Concluyendo, en el presente trabajo se analizan e identifican en forma iniciática, los criterios esenciales para el logro de los objetivos territoriales y las metas institucionales que dentro de la gestión metropolitana, puedan asumir el Estado Provincial y las jurisdicciones municipales, en tanto dispositivos gubernamentales destinados a que legal y orgánicamente, sean orientadas las políticas que tengan el propósito de afrontar tanto los procesos territoriales distorsivos como los déficit, las asimetrías y las carencias socio-ambientales que acusa la población del Gran Paraná

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Three sites were drilled in the Izu-Bonin forearc basin during Ocean Drilling Program (ODP) Leg 126. High-quality formation microscanner (FMS) data from two of the sites provide images of part of a thick, volcaniclastic, middle to upper Oligocene, basin-plain turbidite succession. The FMS images were used to construct bed-by-bed sedimentary sections for the depth intervals 2232-2441 m below rig floor (mbrf) in Hole 792E, and 4023-4330 mbrf in Hole 793B. Beds vary in thickness from those that are near or below the resolution of the FMS tool (2.5 cm) to those that are 10-15 m thick. The bed thicknesses are distributed according to a power law with an exponent of about 1.0. There are no obvious upward thickening or thinning sequences in the bed-by-bed sections. Spaced packets of thick and very thick beds may be a response to (1) low stands of global sea level, particularly at 30 Ma, (2) periods of increased tectonic uplift, or (3) periods of more intense volcanism. Graded sandstones, most pebbly sandstones, and graded to graded-stratified conglomerates were deposited by turbidity currents. The very thick, mainly structureless beds of sandstone, pebbly sandstone, and pebble conglomerate are interpreted as sandy debris-flow deposits. Many of the sediment gravity flows may have been triggered by earthquakes. Long recurrence intervals of 0.3-1 m.y. for the very thickest beds are consistent with triggering by large-magnitude earthquakes (M = 9) with epicenters approximately 10-50 km away from large, unstable accumulations of volcaniclastic sand and ash on the flanks of arc volcanoes. Paleocurrents were obtained from the grain fabric of six thicker sandstone beds, and ripple migration directions in about 40 thinner beds; orientations were constrained by the FMS images. The data from ripples are very scattered and cannot be used to specify source positions. They do, however, indicate that the paleoenvironment was a basin plain where weaker currents were free to follow a broad range of flow paths. The data from sandstone fabric are more reliable and indicate that turbidity currents flowed toward 150? during the time period from 28.9 to 27.3 Ma. This direction is essentially along the axis of the forearc basin, from north to south, with a small component of flow away from the western margin of the basin.

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This airborne hyperspectral (19 bands) image data of Heron Reef, Great Barrier Reef, Australia is derived from Compact Airborne Spectrographic Imager (CASI) data acquired on 1st and 3rd of July 2002, latitude -23.45, longitude 151.92. Processing and correction to at-surface data was completed by Karen Joyce (Joyce, 2004). Raw imagery consisted several images corresponding to the number of flight paths taken to cover the entire Heron Reef. Spatial resolution is one meter. Radiometric corrections converted the at-sensor digital number values to at surface spectral radiance values using sensor specific calibration coefficients and CSIRO's c-WomBat-c atmospheric correction software. Geometric corrections were done using field collected coordinates of features identified in the image. Projection used was Universal Transverse Mercator Zone 56 South and Datum used was WGS 84. Image data is in TIFF format.