Energia renovável: Biodiesel e coletor solar

TCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Agrárias. Curso de Agronomia.Atualmente, a matriz energética mundial é dominada pelos combustíveis fósseis como o carvão, petróleo, gás natural, entre outros. Sabendo que estas, em geral, são mais baratas, representam entraves para o mundo, pelo fato de não ser uma energia renovável e/ou sustentável e causam danos ambientais na sua extração e combustão de forma exagerada. Criaram-se vários programas e eventos internacionais e nacionais visando o incentivo de projetos na produção de biodiesel, etanol e aproveitamento de outras fontes alternativas como sol, vento, marés etc., com a finalidade de aumentar a participação destas fontes na matriz energética mundial e diminuir a dependência energética de combustíveis fosseis, os quais são poluentes. A discussão atual é sobre qual tipo de fonte renovável e/ou oleaginosa a ser industrializada e qual tipo de processos para obtenção da mesma. Partindo deste pressuposto, o objetivo principal deste estudo foi avaliar duas áreas de fontes renováveis de produção de energia limpa sendo a primeira com biodiesel e a segunda com coletor solar. O trabalho foi desenvolvido em duas etapas. A primeira etapa foi realizada no Laboratório de Óleos, Gorduras e Biodiesel (G-Óleo) da Universidade Federal de Lavras (UFLA) e a segunda etapa foi realizada na Estação de Fontes Alternativas de Energia (EFAE) pertencente ao Laboratório de Mecânica, Motores e Máquinas (ENR/CCA) da Universidade Federal de Santa Catarina (UFSC). Na primeira etapa foi feita coleta de óleos residuais em residências, restaurante universitário, restaurantes públicos, hotéis etc. no município de Lavras/MG. Acompanhou-se também as atividades na cadeia de produção de biodiesel, como a extração mecânica de óleo da semente de Moringa oleífera em prensa contínua tipo Expeller e a extração química com Extratores tipo Soxhlet que possibilitou obter a quantidade de óleo restante na torta. Também, realizou-se analises físico-químicas do óleo (índice de acidez, índice de peróxido) e a transesterificação do óleo de Moringa obtido para produção de biodiesel. Na segunda etapa foi construído e avaliado o desempenho de três (3) coletores (aquecedores) solares, sendo, um desenvolvido pela USP/PIRACICABA, um pela CELESC e o terceiro pela UFSC. Neste experimento foi realizada a calibração de sete sensores de temperaturas em um equipamento (Banho Maria) do Laboratório de Análise de Solo, Água e Tecidos Vegetais (ENR/CCA), onde obteve-se suas respectivas equações e curvas de calibração. Foi analisada, a temperatura media da água aquecida, obtendo-se o valor de 35,8oC, 34,3oC e 33,8oC e a energia media acumulada da água aquecida para cada aquecedor foi de 158,84W, 137,04W e 141,27W para o aquecedor solar desenvolvido pela USP, CELESC e UFSC respectivamente. O custo de implantação dos aquecedores (USP e CELESC) foi de R$350,00 e o custo de implantação do aquecedor UFSC foi de R$389,00

Visite des peuplements de pin maritime des Cévennes ardéchoises.

Pour compléter les journées d'études sur le pin maritime, une tournée a été organisée le 23 novembre 2004 dans les Cévennes, en Ardèche et dans le Gard. A Banne (Ardèche), nous avons visité la propriété de Maurice Belval, où ce dernier mène des actions d'amélioration forestière et de prévention des feux de forêt dans les peuplements de pin maritime, et aussi de valorisation du petit bois pour le chauffage

The Bioactive Phenolic Agents Diaryl Ether CVB2-61 and Diarylheptanoid CVB4-57 as Connexin Hemichannel Blockers

Inflammation mediators enhance the activity of connexin (Cx) hemichannels, especially in the epithelial and endothelial tissues. As potential release routes for injury signals, such as (oligo)nucleotides, Cx hemichannels may contribute to long-lasting inflammation. Specific inhibition of Cx hemichannels may therefore be a mode of prevention and treatment of long-lasting, chronic sterile inflammation. The activity of Cx hemichannels was analysed in N2A and HeLa cells transfected with human Cx26 and Cx46 as well as in Calu-3 cells, using dye uptake as functional assay. Moreover, the possible impacts of the bioactive phenolic agents CVB2-61 and CVB4-57 on the barrier function of epithelial cells was analysed using Calu-3 cells. Both agents inhibited the dye uptake in N2A cells expressing Cx26 (>5 µM) and Cx46 (>20 µM). In Calu-3 cells, CVB2-61 and CVB4-57 reversibly inhibited the dye uptake at concentrations as low as 5 µM, without affecting the gap junction communication and barrier function, even at concentrations of 20 µM. While CVB2-61 or CVB4-57 maintained a reduced dye uptake in Calu-3 cells, an enhancement of the dye uptake in response to the stimulation of adenosine signalling was still observed after removal of the agents. The report shows that CVB2-61 and CVB4-57 reversibly block Cx hemichannels. Deciphering the mechanisms of the interactions of these agents with Cx hemichannels could allow further development of phenolic compounds to target Cx hemichannels for better and safer treatment of pathologies that involve Cx hemichannels

Enhancing Vision-Language Pre-training with Rich Supervisions

We propose Strongly Supervised pre-training with ScreenShots (S4) - a novel pre-training paradigm for Vision-Language Models using data from large-scale web screenshot rendering. Using web screenshots unlocks a treasure trove of visual and textual cues that are not present in using image-text pairs. In S4, we leverage the inherent tree-structured hierarchy of HTML elements and the spatial localization to carefully design 10 pre-training tasks with large scale annotated data. These tasks resemble downstream tasks across different domains and the annotations are cheap to obtain. We demonstrate that, compared to current screenshot pre-training objectives, our innovative pre-training method significantly enhances performance of image-to-text model in nine varied and popular downstream tasks - up to 76.1% improvements on Table Detection, and at least 1% on Widget Captioning.Comment: Accepted to CVPR 202

Exercise and Heat Stress in Well-Healed Burn Survivors:Effects of Cooling Modalities on Thermal and Perceptual Responses

PURPOSE: Burn injuries that require grafting impair thermoregulation, which may dissuade individuals with such injuries from being physically active. We tested the hypothesis that cooling modalities attenuate core temperature elevations and perceptions of heat stress during physical activity in the heat among adults with well-healed burn injuries.METHODS: Adults with no burn injuries (non-burned), 20-40% body surface area burn injuries (moderate burn), and &gt; 40% body surface area burn injuries (large burn) performed 1 hour of moderate intensity exercise (2.5 ± 0.2 mph and 2% grade) on four different occasions in two environmental conditions (30 °C &amp; 39 °C, 40% relative humidity). Within each environmental condition, we applied one of the following cooling modalities, random assigned, for each visit: no cooling (control), fan at 4 m/s (fan), water spray every 5 min (water spray; scaled to burn area size), or a combination of water spray + fan.RESULTS: In 30 °C, perceptual strain index (PeSI) was reduced in the non-burned and moderate burn groups with water spray + fan, whereas PeSI was reduced with all cooling modalities in the large burn group. The cooling modalities did not affect core temperature responses. In the 39 °C environment, water spray and water spray + fan attenuated the elevation in core temperature (p ≤ 0.007) only in the large burn group. In the moderate burn group, PeSI was decreased with water spray + fan (p = 0.017). In the large burn group, both water spray alone and water spray + fan (p ≤ 0.041) lowered PeSI.CONCLUSIONS: For both environments across burn groups, the applied cooling modalities were generally more effective at reducing indices of perceptual strain relative to indices of thermal strain (e.g., core temperature).</p

From a movement-deficient grapevine fanleaf virus to the identification of a new viral determinant of nematode transmission

Grapevine fanleaf virus (GFLV) and arabis mosaic virus (ArMV) are nepoviruses responsible for grapevine degeneration. They are specifically transmitted from grapevine to grapevine by two distinct ectoparasitic dagger nematodes of the genus Xiphinema. GFLV and ArMV move from cell to cell as virions through tubules formed into plasmodesmata by the self-assembly of the viral movement protein. Five surface-exposed regions in the coat protein called R1 to R5, which differ between the two viruses, were previously defined and exchanged to test their involvement in virus transmission, leading to the identification of region R2 as a transmission determinant. Region R4 (amino acids 258 to 264) could not be tested in transmission due to its requirement for plant systemic infection. Here, we present a fine-tuning mutagenesis of the GFLV coat protein in and around region R4 that restored the virus movement and allowed its evaluation in transmission. We show that residues T258, M260, D261, and R301 play a crucial role in virus transmission, thus representing a new viral determinant of nematode transmission