1,219 research outputs found

    Multiple epidural steroid injections and body mass index linked with occurrence of epidural lipomatosis: a case series.

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    BACKGROUND: Epidural lipomatosis (EL) is an increase of adipose tissue, normally occurring in the epidural space, sufficient to distort the thecal sac and compress neural elements. There is a lack of knowledge of risk factors, impact on patient\u27s symptoms, and its possible association with epidural steroid injections. METHODS: History, physical examination, patient chart, and MRI were analyzed from 856 outpatients referred for epidural steroid injections. Seventy patients with signs of EL on MRI comprised the study group. Thirty-four randomly selected patients comprised the control group. The severity of EL was determined by the MRI assessment. The impact of EL was determined by the patient\u27s history and physical examination. Logistic regression was used to correlate the probability of developing EL with BMI and epidural steroid injections. RESULTS: EL was centered at L5 and S1 segments. The average BMI for patients with EL was significantly greater than that of control group (36.0 ± 0.9 vs. 29.2 ± 0.9, p \u3c0.01). The probability of developing EL with increasing BMI was linear up to the BMI of 35 after which it plateaued. Triglycerides were significantly higher for the EL group as compared to controls (250 ± 30 vs. 186 ± 21 mg/dL p \u3c 0.01). The odds of having EL were 60% after two epidural steroid injections, 90% after three epidural steroid injections and approached 100% with further injections, independent of BMI. Other risk factors considered included alcohol abuse, use of protease inhibitors, levels of stress, hypothyroidism and genetic predisposition. However there were insufficient quantities to determine statistical significance with a degree of confidence. The impact of EL on patient\u27s symptoms correlated with EL severity with Spearman correlation coefficient of 0.73 at p \u3c 0.01 significance level. CONCLUSIONS: The BMI and triglycerides levels were found to be significantly elevated for the EL group, pointing to an increased risk of EL occurrence in progressively more obese US population. The data also revealed a strong correlation between the number of subsequent epidural steroid injections and EL occurrence calling for caution with the use of corticosteroids

    Comparing Cardiac Dynamics between Neonatal and Adult Rats

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    Background: Cardiovascular physiology studies have been largely limited to adult models; yet, significant developmental differences exist between the immature and adult heart. The field of pediatric research has largely been limited to immortalized cardiomyocyte cell lines, which lack physiologically relevant action potentials, and primary neonatal myocytes that have a limited life span and lack physiologically relevant automaticity. As a result, our understanding of developmental changes in ion channel expression, t-tubule development, and excitation-contraction coupling have been deduced from 2D simplified cell models. To fully understand cardiac development from neonate to adult, a physiologically-relevant 3D whole heart model is needed to monitor dynamic changes in electrical activity and excitation-contraction coupling. Objective: This study aimed to establish a pediatric research model to monitor developmental changes in electrical activity and excitation-contraction coupling, using both imaging tools and electrocardiograms. Methods/Design: Sprague-Dawley rat hearts (3 days – adult) were excised, the aorta was cannulated, and then the heart was transferred to a temperature-controlled constant pressure Langendorff-perfusion system. The perfusate was supplemented with 10 mM blebbistatin to reduce motion artifacts by mechanically uncoupling electrical and mechanical activity. Calcium (50 mg Rhod2-AM) and voltage (62 mg RH237) sensitive dyes were used to stain the heart, signals were acquired using a sCMOS camera (Andor, Zyla 4.2 Plus; \u3e500fps). Electrocardiograms were monitored continuously (lead II configuration) and analyzed using ecgAUTO. Results/Discussion: Initial results showed that compared to adult cohorts, neonatal rats displayed a longer action potential duration (APD80: adult= 85.9ms, neonatal=95.5ms, p=0.026), and a steeper Tau Fall (adults: 33.8ms, neonatal 69.9ms, p=.012) which are likely associated with delayed Ito expression. Calcium handling was also slower in the neonatal hearts (Cad80: Adults: 128.9ms, neonatal=138.8, p=.004), likely due to immature calcium handling and less robust calcium-induced calcium release. The developing excitation-contraction coupling machinery will be further probed using pharmacological tools to elucidate underlying mechanisms; and the newly developed pediatric model will be used for toxicological screening. Acknowledgements: The authors gratefully acknowledge Daniel McInerney for technical assistance. This work was supported by the National Institutes of Health (R00ES023477, R01HL139472), Children’s Research Institute and Children’s National Heart Institute

    Uncertainties in fPAR estimation of grass canopies under different stress situations and differences in architecture

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    The fraction of intercepted photosynthetic active radiation (fPAR) is a key variable used by the Monteith model to estimate the net primary productivity (NPP). This variable can be assessed by vegetation indices (VIs) derived from spectral remote sensing data but several factors usually affect their relationship. The objectives of this work were to analyse the fPAR dynamics and to describe the relationships between fPAR and several indices (normalized difference vegetation index (NDVI), optimized soil adjusted vegetation index (OSAVI), GreenNDVI (GNDVI), visible atmospherically resistant index (VARI) green, VIgreen and red edge position (REP)) under different water and nutrient treatments for two species with different canopy architectures. Two C3 grass species with differences in leaf orientation (planophile and erectophile) were cultivated from seeds in pots. Four treatments were applied combining water and nitrogen availability. Every week, canopy reflectance and fPAR were measured. Aerial biomass was clipped to estimate final above-ground production for each species and treatment. Starting from reflectance values, the indices were calculated. Planophile species have a steeper (but not significantly) slope inVIs-fPAR relationships than the erectophile species. Water and nutrient deficiencies treatment showed no relationship with fPAR in any spectral index in the erectophile species. In the other species, this treatment showed significant relationship according to the index used. Analysing each species individually, treatments did not modify slopes except in one case (planophile species between both treatments with high nitrogen but differing in water availability). Among indices, GNDVI was the best estimator of fPAR for both species, followed by NDVI and OSAVI. Inaccurate results may be obtained from commonly reported spectral relationships if plants' stress factors are not taken into account.Fil: Cristiano, Piedad María. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; ArgentinaFil: Posse, G.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; ArgentinaFil: Di Bella, Carlos Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; ArgentinaFil: Jaimes, Florencia Romina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Clima y Agua; Argentin

    ELVIS: Entertainment-led video summaries

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    © ACM, 2010. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in ACM Transactions on Multimedia Computing, Communications, and Applications, 6(3): Article no. 17 (2010) http://doi.acm.org/10.1145/1823746.1823751Video summaries present the user with a condensed and succinct representation of the content of a video stream. Usually this is achieved by attaching degrees of importance to low-level image, audio and text features. However, video content elicits strong and measurable physiological responses in the user, which are potentially rich indicators of what video content is memorable to or emotionally engaging for an individual user. This article proposes a technique that exploits such physiological responses to a given video stream by a given user to produce Entertainment-Led VIdeo Summaries (ELVIS). ELVIS is made up of five analysis phases which correspond to the analyses of five physiological response measures: electro-dermal response (EDR), heart rate (HR), blood volume pulse (BVP), respiration rate (RR), and respiration amplitude (RA). Through these analyses, the temporal locations of the most entertaining video subsegments, as they occur within the video stream as a whole, are automatically identified. The effectiveness of the ELVIS technique is verified through a statistical analysis of data collected during a set of user trials. Our results show that ELVIS is more consistent than RANDOM, EDR, HR, BVP, RR and RA selections in identifying the most entertaining video subsegments for content in the comedy, horror/comedy, and horror genres. Subjective user reports also reveal that ELVIS video summaries are comparatively easy to understand, enjoyable, and informative

    Hermenêutica da pergunta pedagógica: Aprendizagem mediada pela prática da liberdade a partir da perspectiva de Freire

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    El ser humano se aproxima al mundo mediante la dialéctica de pregunta y respuesta para construir socialmente la realidad mediante la práctica de la libertad. En este contexto, el estudio se realizó con el objetivo de exponer el análisis hermenéutico de la pregunta pedagógica como instrumento pedagógico para el aprendizaje mediado por la práctica de la libertad desde la perspectiva de Freire. Desde el campo de la investigación filosófica se desarrollaron tres etapas (construcción del horizonte de comprensión, destructiva y constructiva) para proyectar la tradición educativa de Vigotsky y Ausubel hacia la hermenéutica de la pregunta y confrontar el aporte de la pedagogía de la pregunta de Freire. Los resultados obtenidos recuperan la pregunta inicial, mediadora y esencial situándolas en relación con la estructura y horizonte de la pregunta. El acto de preguntar se rehabilita como práctica de la libertad al mediar el aprendizaje desde el pensamiento crítico y creativo.The man approaches the world through the dialectic of question and answer to socially construct reality by practicing freedom. In this context, the study was conducted with the aim of exposing the hermeneutical analysis of the pedagogical question as an educational tool for learning through practice of freedom from the perspective of Freire. From the field of philosophical inquiry three stages (construction horizon of understanding, destructive and constructive) were developed to project the educational tradition of Vygotsky and Ausubel hermeneutics to question and confront the contribution of pedagogy Freire's question. The results obtained recover the initial question, mediator and essential placing them in relation to the structure and horizon of the question. The act of asking is rehabilitated as a practice of freedom to mediate learning from the critical and creative thinkingO ser humano aproxima-se ao mundo mediante a dialética de pergunta e resposta para construir socialmente a realidade mediante a prática da liberdade. Neste contexto, o estudo realizou-se com o objetivo de expor a análise hermenêutica da pergunta pedagógica como instrumento pedagógico para a aprendizagem mediada pela prática de liberdade a partir da perspectiva de Freire. Do campo da investigação filosófica desenvolveram-se três etapas (construção do horizonte de compreensão, destrutiva e construtiva) para projetar a tradição educativa de Vigotsky e Ausubel para a hermenêutica da pergunta e confrontar a contribuição da pedagogia da pergunta de Freire. Os resultados obtidos recuperam a pergunta inicial, mediadora e essencial situando-as em relação com a estrutura e horizonte da pergunta. O ato de perguntar reabilita-se como prática da liberdade ao mediar a aprendizagem a partir do pensamento crítico e criativ

    Water balance in Dhoro Naro Minor Command Area Sindh, Pakistan: technical report. Thesis

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    Water balance / Water table / Monitoring / Groundwater / Recharge / Discharges / Mathematical models / Measurement / Flumes / Pumping / Tube wells / Aquifers / Computer software / Irrigation management / Precipitation / Evapotranspiration / Drainage / Seepage loss / Soil moisture / Pakistan / Sindh / Dhoro Naro Minor Command Area / Nawabshah Sub-project

    Assessing Mn as an antioxidant agent in bioactive glasses by quantification of catalase and superoxide dismutase enzymatic mimetic activities

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    The antioxidant activity of Mn as additive in a 45S5 type glass system with and without P2O5 was studied by mimicking the activity of catalase (CMA) and superoxide dismutase (SOD) enzymes. Glasses were melted either under oxidizing or reducing atmosphere (N2/H2) to compare the processing influence on the Mn oxidation state. Thermal (DTA) and optical (UV–Vis) characterizations of the glass powders were carried out to obtain further insight into the structural role of Mn. A correlation of in vitro apatite formation between Tris buffer solution and Simulated Body Fluid (SBF) was performed to optimise Mn substitution, where a decrease in apatite formation was observed by increasing Mn content. Despite this, glasses with up to 1.0 mol% MnO did not show any delay in apatite formation and maintained their CMA and SOD activity. The antioxidant effect of Mn can be attributed to the interconversion Mn2+ ↔ Mn3+ occurring on the glass surface through a heterogeneous catalysis. P2O5 plays an important role in the antioxidant effect of the glass, possibly by charge balancing Mn ions and forming more stable units compared to those formed with Ca and Na. The amount of Mn2+ is predominant in the glass network with respect to Mn3+ in all synthetized glasses. Moreover, glass melting in a reducing atmosphere further avoided Mn oxidation

    Rendezvous consensus algorithm applied to the location of possible victims in disaster zones

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    In this paper is presented an alternative to performing the analysis of the sensors in the field of applied cooperative robotics for search and location of disaster victims. This work proposes the use of the Rendezvous algorithm to validate the information coming from the sensors of a multi-robot system. The sensors located in each one of the robotic agents provide a measured value according to the existence or not of victims in the surrounding zone to the robot. Since the information coming from the robots is not the same, however, its belong to the same sensed parameters, the Rendezvous algorithm is used to find a consensus of opinion about the existence of victims. In addition, the swarm of robots uses bio-inspired techniques to generate the navigation algorithm. This navigation algorithm was inspired by the foraging technique used by swarms such as bees, birds or bacteria. The results present some Rendezvous algorithm simulation and robot swarm navigation showing the feasibility of the proposed system.http://unidadinvestigacion.usta.edu.c

    Determinants of TRPV4 Activity following Selective Activation by Small Molecule Agonist GSK1016790A

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    TRPV4 (Transient Receptor Potential Vanilloid 4) channels are activated by a wide range of stimuli, including hypotonic stress, non-noxious heat and mechanical stress and some small molecule agonists (e.g. phorbol ester 4α-PDD). GSK1016790A (GSK101) is a recently discovered specific small molecule agonist of TRPV4. Its effects on physical determinants of TRPV4 activity were evaluated in HeLa cells transiently transfected with TRPV4 (HeLa-TRPV4). GSK101 (10 nM) causes a TRPV4 specific Ca2+ influx in HeLa-TRPV4 cells, but not in control transfected cells, which can be inhibited by ruthenium red and Ca2+-free medium more significantly at the early stage of the activation rather than the late stage, reflecting apparent partial desensitization. Western blot analysis showed that GSK101 activation did not induce an increase in TRPV4 expression at the plasma membrane, but caused an immediate and sustained downregulation of TRPV4 on the plasma membrane in HeLa-TRPV4 cells. Patch clamp analysis also revealed an early partial desensitization of the channel which was Ca2+-independent. FRET analysis of TRPV4 subunit assembly demonstrated that the GSK101-induced TRPV4 channel activation/desensitization was not due to alterations in homotetrameric channel formation on the plasma membrane. It is concluded that GSK101 specifically activates TRPV4 channels, leading to a rapid partial desensitization and downregulation of the channel expression on the plasma membrane. TRPV4 subunit assembly appears to occur during trafficking from the ER/Golgi to the plasma membrane and is not altered by agonist stimulation

    9. UTILIZACIÓN DE RESIDUOS DE LA INDUSTRIA PAPELERA PARA LA CRÍA DE LA LOMBRIZ ROJA CALIFORNIANA (EISENIA FOETIDA), EN LA GENERACIÓN DE VERMICOMPOST

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    La industria papelera genera gran cantidad de residuos ya que por cada de tonelada de papel, se generan 200 kilos de residuos o lodos papeleros. Esta investigación tuvo como objetivo principal determinar la viabilidad del lodo papelero como fuente de alimento para la cría de lombriz roja californiana (Eisenia foetida) en mezclas con estiércol bovino, hacia la obtención de vermicompost o una enmienda al suelo. Dar un uso a este residuo se puede convertir en una alternativa de solución ambiental y económica frente a su disposición en vertederos. El experimento se realizó en las instalaciones de la Finca El Caney, sede Rural del Centro para el Desarrollo Agroecológico y Agroindustrial (Sabanalarga, Atlántico). Para realizar el experimento se realizaron tratamientos utilizando lodo con estiércol de bovino en proporciones del 100%, 75%, 50%, 25% y 0%. Por cada tratamiento se realizaron 3 repeticiones. El diseño estadístico seleccionado fue Bloques completos al azar, y análisis de medias Prueba Tukey. El lodo papelero provino del residuo del papel tiramisut elaborado por la empresa UNIBOL S.A de Barranquilla. El mejor tratamiento fue el de 75% de estiércol y 25% de lodo. Otros aspectos como sus contenidos y comercialización fueron tenidos en cuenta en la investigación
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