Estimação do iuv máximo mensal no semi-árido do nordeste do Brasil – estudo de caso Agua Branca - AL

O código computacional, SPCTRL2, foi utilizado para estimar a irradiação solar ultravioleta na localidade de Água Branca - AL (Longitude -37º 56’ e Latitude -9º 15'), região semiárida do Nordeste do Brasil, para o ano de 2008. O software requer poucos parâmetros de entrada e fáceis de obter: ângulo zenital, pressão atmosférica, quantidade de água precipitável, o ozônio total e a profundidade óptica de aerossóis (AOD). Todas essas variáveis são medidas em estações meteorológicas convencionais, com exceção da profundidade óptica de aerossol(AOD). A AOD utilizada para a simulação foi estimada à partir do índice de turbidez de Linke calculado pelo modelo ESRA (European Solar Radiation Atlas). As estimativas realizadas mostraram um IUV no período das 9 às 17 horas elevados praticamente durante todo o ano e índices extremos iguais a 13 nos meses de fevereiro, março, outubro, novembro e dezembro.The computational code, SPCTRL2, was used to estimate the solar ultraviolet irradiation in the town of Água Branca - AL (Longitude -37 ° 56 ' Latitude and -9 º 15'), semi-arid region of Northeast Brazil, for the year 2008. The software requires few input parameters and easy to obtain: zenith angle, atmospheric pressure, amount of precipitable water, total ozone and aerosol optical depth (AOD). All these variables are measured in conventional meteorological stations, with the exception of the aerosol optical depth (AOD). AOD used for the simulation was estimated from the turbidity Linke calculated by the ESRA model (European Solar Radiation Atlas). The estimates made in the period showed an UVI from 9 to 17 o'clock high during the whole year and extreme rates equal to 13 in February, March, October, November and December.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Estimación de producción de energía eléctrica por una central solar de concentración de 1 MWe. caso de estudio: provincia de Salta (Argentina)

En este trabajo se estima la producción de energía eléctrica utilizando un modelo analítico de una central solar térmica de concentración cilindro-parabólica de foco lineal, de 1 MWe de potencia nominal. Los datos de irradiancia solar directa normal al haz, en frecuencia horaria, para Salta Ciudad y San Carlos (Provincia de Salta), fueron extraídos de la base de datos satelital CM SAF abarcando el periodo de 2000-2005, generando un año típico para cada sitio. Los valores de energía obtenidos, en ambos sitios, están relacionados con la disponibilidad de energía solar en cada sitio.Fil: Gonzalez, Jose Antonio. Universidad Nacional de Salta; ArgentinaFil: Lozano, R. F.. Universidad Nacional de Salta; ArgentinaFil: Hongn, Marcos Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Durán, Gonzalo José. Universidade Federal de Pernambuco; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Cinco, P. E.. Universidade Federal de Pernambuco; BrasilFil: Castro Vilela, O.. Universidade Federal de Pernambuco; BrasilFil: Fraidenraich, N.. Universidade Federal de Pernambuco; BrasilFil: Salazar, Germán Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; Argentin

Muscle activation during gait in children with Duchenne muscular dystrophy

The aim of this prospective study was to investigate changes in muscle activity during gait in children with Duchenne muscular Dystrophy (DMD). Dynamic surface electromyography recordings (EMGs) of 16 children with DMD and pathological gait were compared with those of 15 control children. The activity of the rectus femoris (RF), vastus lateralis (VL), medial hamstrings (HS), tibialis anterior (TA) and gastrocnemius soleus (GAS) muscles was recorded and analysed quantitatively and qualitatively. The overall muscle activity in the children with DMD was significantly different from that of the control group. Percentage activation amplitudes of RF, HS and TA were greater throughout the gait cycle in the children with DMD and the timing of GAS activity differed from the control children. Significantly greater muscle coactivation was found in the children with DMD. There were no significant differences between sides. Since the motor command is normal in DMD, the hyper-activity and co-contractions likely compensate for gait instability and muscle weakness, however may have negative consequences on the muscles and may increase the energy cost of gait. Simple rehabilitative strategies such as targeted physical therapies may improve stability and thus the pattern of muscle activity

Cell Therapy of Congenital Corneal Diseases with Umbilical Mesenchymal Stem Cells: Lumican Null Mice

BACKGROUND: Keratoplasty is the most effective treatment for corneal blindness, but suboptimal medical conditions and lack of qualified medical personnel and donated cornea often prevent the performance of corneal transplantation in developing countries. Our study aims to develop alternative treatment regimens for congenital corneal diseases of genetic mutation. METHODOLOGY/PRINCIPAL FINDINGS: Human mesenchymal stem cells isolated from neonatal umbilical cords were transplanted to treat thin and cloudy corneas of lumican null mice. Transplantation of umbilical mesenchymal stem cells significantly improved corneal transparency and increased stromal thickness of lumican null mice, but human umbilical hematopoietic stem cells failed to do the same. Further studies revealed that collagen lamellae were re-organized in corneal stroma of lumican null mice after mesenchymal stem cell transplantation. Transplanted umbilical mesenchymal stem cells survived in the mouse corneal stroma for more than 3 months with little or no graft rejection. In addition, these cells assumed a keratocyte phenotype, e.g., dendritic morphology, quiescence, expression of keratocyte unique keratan sulfated keratocan and lumican, and CD34. Moreover, umbilical mesenchymal stem cell transplantation improved host keratocyte functions, which was verified by enhanced expression of keratocan and aldehyde dehydrogenase class 3A1 in lumican null mice. CONCLUSIONS/SIGNIFICANCE: Umbilical mesenchymal stem cell transplantation is a promising treatment for congenital corneal diseases involving keratocyte dysfunction. Unlike donated corneas, umbilical mesenchymal stem cells are easily isolated, expanded, stored, and can be quickly recovered from liquid nitrogen when a patient is in urgent need

Dystropathology increases energy expenditure and protein turnover in the mdx mouse model of Duchenne muscular dystrophy

The skeletal muscles in Duchenne muscular dystrophy and the mdx mouse model lack functional dystrophin and undergo repeated bouts of necrosis, regeneration, and growth. These processes have a high metabolic cost. However, the consequences for whole body energy and protein metabolism, and on the dietary requirements for these macronutrients at different stages of the disease, are not well-understood. This study used juvenile (4- to 5- wk-old) and adult (12- to 14-wk-old) male dystrophic C57BL/10ScSn-mdx/J and age-matched C57BL/10ScSn/J control male mice to measure total and resting energy expenditure, food intake, spontaneous activity, body composition, whole body protein turnover, and muscle protein synthesis rates. In juvenile mdx mice that have extensive muscle damage, energy expenditure, muscle protein synthesis, and whole body protein turnover rates were higher than in age-matched controls. Adaptations in food intake and decreased activity were insufficient to meet the increased energy and protein needs of juvenile mdx mice and resulted in stunted growth. In (non-growing) adult mdx mice with less severe dystropathology, energy expenditure, muscle protein synthesis, and whole body protein turnover rates were also higher than in age-matched controls. Food intake was sufficient to meet their protein and energy needs, but insufficient to result in fat deposition. These data show that dystropathology impacts the protein and energy needs of mdx mice and that tailored dietary interventions are necessary to redress this imbalance. If not met, the resultant imbalance blunts growth, and may limit the benefits of therapies designed to protect and repair dystrophic muscles

Current Bioengineering and Regenerative Strategies for the Generation of Kidney Grafts on Demand

[EN] Currently in the USA, one name is added to the organ transplant waiting list every 15 min. As this list grows rapidly, fewer than one-third of waiting patients can receive matched organs from donors. Unfortunately, many patients who require a transplant have to wait for long periods of time, and many of them die before receiving the desired organ. In the USA alone, over 100,000 patients are waiting for a kidney transplant. However, it is a problem that affects around 6% of the word population. Therefore, seeking alternative solutions to this problem is an urgent work. Here, we review the current promising regenerative technologies for kidney function replacement. Despite many approaches being applied in the different ways outlined in this work, obtaining an organ capable of performing complex functions such as osmoregulation, excretion or hormone synthesis is still a long-term goal. However, in the future, the efforts in these areas may eliminate the long waiting list for kidney transplants, providing a definitive solution for patients with end-stage renal disease.This study was supported by a grant from ALCER-TURIA, ASTELLAS and PRECIPITA CROWDFUNDING.Garcia-Dominguez, X.; Vicente Antón, JS.; Vera Donoso, CD.; Marco-Jiménez, F. (2017). Current Bioengineering and Regenerative Strategies for the Generation of Kidney Grafts on Demand. Current Urology Reports. 18(1):1-8. https://doi.org/10.1007/s11934-017-0650-6S18181Ott HC, Mathisen DJ. Bioartificial tissues and organs: are we ready to translate? Lancet. 2011;378:1977–8.Salvatori M, Peloso A, Katari R, Orlando G. Regeneration and bioengineering of the kidney: current status and future challenges. Curr Urol Rep. 2014;15:379.D’Agati VD. Growing new kidneys from embryonic cell suspensions: fantasy or reality? J Am Soc Nephrol. 2002;11:1763–6.Abouna GM. Organ shortage crisis: problems and possible solutions. 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They demonstrated the potential of this technique as a possible solution to the kidneys shortage.Yokote S, Yokoo T, Matsumoto K, Utsunomiya Y, Kawamura T, Hosoya T. The effect of metanephroi transplantation on blood pressure in anephric rats with induced acute hypotension. Nephrol Dial Transplant. 2012;27:3449–55.Matsumoto K, Yokoo T, Yokote S, Utsunomiya Y, Ohashi T, Hosoya T. Functional development of a transplanted embryonic kidney: effect of transplantation site. J Nephrol. 2012;25:50–5.Yokote S, Yokoo T, Matsumoto K, Ohkido I, Utsunomiya Y, Kawamura T, et al. Metanephroi transplantation inhibits the progression of vascular calcification in rats with adenine-induced renal failure. Nephron Exp Nephrol. 2012;120:e32–40.Matsumoto K, Yokoo T, Matsunari H, Iwai S, Yokote S, Teratani T, et al. Xeno‐transplanted embryonic kidney provides a niche for endogenous mesenchymal stem cell differentiation into erythropoietin-producing tissue. Stem Cells. 2012;30:1228–35.Abrahamson DR. 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Transplantation of metanephroi across the major histocompatibility complex in rats. Am J Physiol Regul Integr Comp Physiol. 2001;280:R132–6.Vera-Donoso CD, García-Dominguez X, Jiménez-Trigos E, García-Valero L, Vicente JS, Marco-Jiménez F. Laparoscopic transplantation of metanephroi: a first step to kidney xenotransplantation. Actas Urol Esp. 2015;39:527–34.•• Marco-Jiménez F, Garcia-Dominguez X, Jimenez-Trigos E, Vera-Donoso CD, Vicente JS. Vitrification of kidney precursors as a new source for organ transplantation. Cryobiology. 2015;70:278–82. This study found that it is possible to create a long-term biobank of kidney precursors as an unlimited source of organs for transplantation and open new therapeutic possibilities for the patients with chronic renal failure.Garcia-Dominguez X, Vicente JS, Vera-Donoso C, Jimenez-Trigos E, Marco-Jiménez F. First steps towards organ banks: vitrification of renal primordia. 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Cryobiology. 2014;68:294–302

OPTICAL PROPERTIES OF V-TROUGH CONCENTRATORS

Abstract--A new approach to study the optical behavior of V-trough concentrators is developed, based on the use of three characteristic angles defining the appearance, disappearance and return to the outside space of the cavity of a reflection mode. The probability of occurrence of a given number of reflections for beam radiation is determined as a function of these angles and the optical efficiency calculated. It is shown that the optical efficiency can be approximated by a function of two parameters, the angular acceptance function, T, and the mean number of reflections, n, as T. p,/r. Deviations between exact and approximate optical efficiency increase as n increases or as p decreases. For troughs with C _< 2.5 the maximal error for beam radiation is 3.4% for p > 0.8 (8.3% for p >-0.7). For diffuse radiation the maximal error is less than 2% for configurations whose optical efficiency is above 0.6. A further simplification was introduced to obtain the optical efficiency for diffuse radiation, approximating T by an analytical expression and n by an empirical linear function of the inverse of the vertex angle. Results accurate up to 5% for p = 0.8, were obtained. Increasing the concentration ratio, C, from 1.5 to 2.5 for a vertex angle being one third of the acceptance angle, decreased the optical efficiency from 0.74 to 0.59, for p = 0.8. For a given C, the dependence of the optical efficiency on the vertex angle is rather weak, suggesting that large trough angles might be favoured by cost-benefit analysis. INTRODUCFION V-trough cavities used in conjunction with commercial photocells can be an effective way to reduce the cost of the energy produced by photovoltaic panels. The walls of the cavity being plane, enable the use of lowcost, good-quality mirrors, with the benefit of a high optical efficiency. If at the same time the V-trough concentrator can be built at a moderate cost, the use of photovoitaic panels coupled to V-trough concentrators can result in a favourable cost-benefit ratio. The performance of the V-trough concentrator is characterized by the optical efficiency, which strongly depends on the incidence angle. It was shown by Rabl No simplified procedure is available for obtaining the optical efficiency as a function of the incidence angle. In this case the probability Pk(i) for a light ray to undergo k reflections on its passage through the op-* ISES member. tical cavity, when it reaches the aperture at an incidence angle i, has to be known. This probability can be calculated by graphical, numerical or analytical methods. The optical efficiency is then written as where M is the maximum number of reflections, for the incidence angle i. Although Pk(i) has to be obtained by detailed calculations, it will be shown that, similarly to The optical properties of V-trough concentrators were studied by Hollands [ 3 ] and some general features described by Rabl [ 4 ]. Hollands [ 3 ] calculates the effective concentration for beam radiation at the cavity absorber for several concentration ratios. The optical cavities studied i

Error Probability of Binary and M-ary Signals with Spatial Diversity in Nakagami-q (Hoyt) Fading Channels

We analyze the exact average symbol error probability (SEP) of binary and M-ary signals with spatial diversity in Nakagami-q (Hoyt) fading channels. The maximal-ratio combining and orthogonal space-time block coding are considered as diversity techniques for single-input multiple-output and multiple-input multiple-output systems, respectively. We obtain the average SEP in terms of the Lauricella multivariate hypergeometric function FD(n). The analysis is verified by comparing with Monte Carlo simulations and we further show that our general SEP expressions particularize to the previously known results for Rayleigh (q = 1) and single-input single-output (SISO) Nakagami-q cases