Desenvolvimento tecnológico e inserção da energia solar no Brasil

Bibliografia: p. 111-113O mercado global de energia solar cresceu de forma exponencial nos últimos anos. Várias aplicações de energia solar tornaram-se viáveis economicamente pela expansão dos mercados e pela consequente expansão das escalas de produção. Este artigo contextualiza o Brasil no quadro global de exploração das diversas tecnologias de geração de energia solar. Com base nessa contextualização, são avaliadas as possibilidades de criação de incentivos e de articulação de políticas públicas em prol do uso desse tipo de energia no país, com um olhar sobre o adensamento produtivo e tecnológico local.The global market for solar energy has grown exponentially in the last years. Several solar energy applications have become economically viable because of the markets expansion and, as a consequence, because of the expansion of the production scale. This paper gives the context in which Brazil is, regarding the global picture of several uses of technologies for solar energy generation. Given this context, it is evaluated the possibilities for the creation of incentives and public policies coordination in favor of this source of energy in the country, with a local supply chain and a local technological development

Spermatogonial kinetics in humans

The human spermatogonial compartment is essential for daily production of millions of sperm. Despite this crucial role, the molecular signature, kinetic behavior and regulation of human spermatogonia are poorly understood. Using human testis biopsies with normal spermatogenesis and by studying marker protein expression, we have identified for the first time different subpopulations of spermatogonia. MAGE-A4marks all spermatogonia, KITmarks all Bspermatogonia and UCLH1 all Apale-dark (Ap-d) spermatogonia. We suggest that at the start of the spermatogenic lineage there are Ap-d spermatogonia that are GFRA1High, likely including the spermatogonial stem cells. Next, UTF1 becomes expressed, cells become quiescent and GFRA1 expression decreases. Finally, GFRA1 expression is lost and subsequently cells differentiate into B spermatogonia, losing UTF1 and acquiring KIT expression. Strikingly, most human Ap-d spermatogonia are out of the cell cycle and even differentiating type B spermatogonial proliferation is restricted. A novel scheme for human spermatogonial development is proposed that will facilitate further research in this field, the understanding of cases of infertility and the development of methods to increase sperm output

Social innovation within network-based plataforms as a COVID-19 response strategy: the matchfunding enfrente

Analisamos a plataforma de investimento colaborativo Matchfunding Enfrente e suas ações de combate à pandemia da COVID-19. Inicialmente, apresentamos o modelo de financiamento matchfunding, tratamos do modo como a plataforma Enfrente se constitui em um dispositivo de inovação social e ponderamos sobre suas limitações no âmbito de raça e gênero. Em seguida, refletimos sobre a inserção do Matchfunding Enfrente no quadro das teorias sobre redes e plataformas. Ao final, reiteramos nossas considerações de que projetos de inovação social necessitam de aprimoramentos constantes113Redes de Comunicação e Narrativas em Saúde - Parte 2108126We analyzed the Matchfunding Enfrentecollaborative investment platform and its responsive actions to the COVID-19 pandemic. Through the usage of a single case study methodology (YIN, 2001), we present the matchfunding financing method, considering the Enfrente platform as a social innovative project and debating its limitations in terms of race and gender. Afterwards, we show the platform’s articulations among agents from the organized civil society and private companies. We also discuss the Matchfunding Enfrente in the framework of networks and platforms’ theories. In the end, we emphasize our considerations that social innovative projects must improve constantl

Electrospun Poly(3-Hydroxybutyrate-Co-3-Hydroxyvalerate)/Olive Leaf Extract Fiber Mesh as Prospective Bio-Based Scaffold for Wound Healing

Polyhydroxyalkanoates (PHAs) are a family of biopolyesters synthesized by various microorganisms. Due to their biocompatibility and biodegradation, PHAs have been proposed for biomedical applications, including tissue engineering scaffolds. Olive leaf extract (OLE) can be obtained from agri-food biowaste and is a source of polyphenols with remarkable antioxidant properties. This study aimed at incorporating OLE inside poly(hydroxybutyrate-co-hydroxyvalerate) (PHBHV) fibers via electrospinning to obtain bioactive bio-based blends that are useful in wound healing. PHBHV/OLE electrospun fibers with a size of 1.29 ± 0.34 µm were obtained. Fourier transform infrared chemical analysis showed a uniform surface distribution of hydrophilic -OH groups, confirming the presence of OLE in the electrospun fibers. The main OLE phenols were released from the fibers within 6 days. The biodegradation of the scaffolds in phosphate buffered saline was investigated, demonstrating an adequate stability in the presence of metalloproteinase 9 (MMP-9), an enzyme produced in chronic wounds. The scaffolds were preliminarily tested in vitro with HFFF2 fibroblasts and HaCaT keratinocytes, suggesting adequate cytocompatibility. PHBHV/OLE fiber meshes hold promising features for wound healing, including the treatment of ulcers, due to the long period of durability in an inflamed tissue environment and adequate cytocompatibility

A CADEIA AGROINDUSTRIAL ORIZÍCOLA DO RIO GRANDE DO SUL

Rice is an essential good for the Brazilian consumer’s food basket, and is one of the main food consumed daily. The increasingly productivity made Brazil to reach the self-sufficiency in rice production in 2004. However, the country has continued being a net importer. Imports contribute to keep the domestic prices in lower levels. So, it is important to characterize the main agents involved in this agri-industrial chain, in the rice production and distribution, as well as identify the relevant variables to the domestic prices formation. Afterward, the objective of this paper, based on a survey, is to propose a sketch of the chain structure for the RS state that is responsible for over 50% of the Brazilian paddy rice production.No Brasil, o arroz é considerado um produto essencial na cesta básica do consumidor, sendo um dos principais alimentos consumidos diariamente pela população. Com o crescimento da produtividade, em 2004 o Brasil tornou-se autossuficiente na produção do arroz. Contudo, manteve-se como um importador líquido. A importação contribui para manter os preços domésticos em patamares mais baixos. Diante disso, julga-se importante caracterizar os principais agentes da cadeia produtiva, envolvidos na sua produção e comercialização, bem como identificar as variáveis relevantes para a formação de preço no mercado doméstico. Nesse sentido, o objetivo deste trabalho, com base em levantamentos de campo, é propor uma estrutura para a cadeia do arroz no RS, estado responsável por mais de 50% da produção nacional do produto

A Cautionary Tale: MARVELS Brown Dwarf Candidate Reveals Itself To Be A Very Long Period, Highly Eccentric Spectroscopic Stellar Binary

We report the discovery of a highly eccentric, double-lined spectroscopic binary star system (TYC 3010-1494-1), comprising two solar-type stars that we had initially identified as a single star with a brown dwarf companion. At the moderate resolving power of the MARVELS spectrograph and the spectrographs used for subsequent radial-velocity (RV) measurements (R ~ <30,000), this particular stellar binary mimics a single-lined binary with an RV signal that would be induced by a brown dwarf companion (Msin(i)~50 M_Jup) to a solar-type primary. At least three properties of this system allow it to masquerade as a single star with a very low-mass companion: its large eccentricity (e~0.8), its relatively long period (P~238 days), and the approximately perpendicular orientation of the semi-major axis with respect to the line of sight (omega~189 degrees). As a result of these properties, for ~95% of the orbit the two sets of stellar spectral lines are completely blended, and the RV measurements based on centroiding on the apparently single-lined spectrum is very well fit by an orbit solution indicative of a brown dwarf companion on a more circular orbit (e~0.3). Only during the ~5% of the orbit near periastron passage does the true, double-lined nature and large RV amplitude of ~15 km/s reveal itself. The discovery of this binary system is an important lesson for RV surveys searching for substellar companions; at a given resolution and observing cadence, a survey will be susceptible to these kinds of astrophysical false positives for a range of orbital parameters. Finally, for surveys like MARVELS that lack the resolution for a useful line bisector analysis, it is imperative to monitor the peak of the cross-correlation function for suspicious changes in width or shape, so that such false positives can be flagged during the candidate vetting process.Comment: 16 pages, 11 figures, 6 table

Glucose Sensing by Time-Resolved Fluorescence of Sol-Gel Immobilized Glucose Oxidase

A monolithic silica gel matrix with entrapped glucose oxidase (GOD) was constructed as a bioactive element in an optical biosensor for glucose determination. Intrinsic fluorescence of free and immobilised GOD was investigated in the visible range in presence of different glucose concentrations by time-resolved spectroscopy with time-correlated single-photon counting detector. A three-exponential model was used for analysing the fluorescence transients. Fractional intensities and mean lifetime were shown to be sensitive to the enzymatic reaction and were used for obtaining calibration curve for glucose concentration determination. The sensing system proposed achieved high resolution (up to 0.17 mM) glucose determination with a detection range from 0.4 mM to 5 mM

Effects of exposure to cigarette smoke prior to pregnancy in diabetic rats

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to evaluate the effects of cigarette smoke exposure before pregnancy on diabetic rats and their offspring development.</p> <p>Methods</p> <p>Diabetes was induced by streptozotocin and cigarette smoke exposure was conducted by mainstream smoke generated by a mechanical smoking device and delivered into a chamber. Diabetic female Wistar rats were randomly distributed in four experimental groups (n minimum = 13/group): nondiabetic (ND) and diabetic rats exposed to filtered air (D), diabetic rats exposed to cigarette smoke prior to and into the pregnancy period (DS) and diabetic rats exposed to cigarette smoke prior to pregnancy period (DSPP). At day 21 of pregnancy, rats were killed for maternal biochemical determination and reproductive outcomes.</p> <p>Results</p> <p>The association of diabetes and cigarette smoke in DSPP group caused altered glycemia at term, reduced number of implantation and live fetuses, decreased litter and maternal weight, increased pre and postimplantation loss rates, reduced triglyceride and VLDL-c concentrations, increased levels of thiol groups and MDA. Besides, these dams presented increased SOD and GSH-Px activities. However, the increased antioxidant status was not sufficient to prevent the lipid peroxidation observed in these animals.</p> <p>Conclusion</p> <p>Despite the benefits stemming from smoking interruption during the pregnancy of diabetic rats, such improvement was insufficient to avoid metabolic alterations and provide an adequate intrauterine environment for embryofetal development. Therefore, these results suggest that it is necessary to cease smoking extensive time before planning pregnancy, since stopping smoking only when pregnancy is detected may not contribute effectively to fully adequate embryofetal development.</p