Pastagens em sistemas silvipastoris.

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Experimental assessment of low temperature phase change materials (PCM) for refrigerating and air conditioning applications

Refrigeration, air conditioning and heat pump sector represents between 25 and 30% of the global consumption of electricity and this figure is expected to rapidly grow due to the current trend of electrification. To increase the efficiency of these systems or to maximize the use of renewable energy, latent thermal storage systems are being studied and recommended. However, there is a lack of reliable design rules based on trustable data that could help the thermal experts to design efficient and cost-effective latent thermal energy storage. This paper follows a previous work recently published (Longo et al., 2022) where the thermo-physical and transport properties of a few low temperature PCMs (i.e. 2–9 °C of melting temperature) were measured and discussed. In the present work, the attention is focused on two other fundamental aspects: the PCMs’ compatibility with the most common construction materials and their thermal behaviour during the solid/liquid phase change. The collected results will contribute to add currently unavailable data in the literature and to highlight interesting insights on the performance of the selected PCMs

Beta-Cyclodextrin: Eugenol Inclusion Complexes: Characterization and Antifungal Capacity

Eugenol (EUG) is the principal component of clove essential oil. It has demonstrated excellent antifungal properties against B. cinerea, one of the most important fungus in the fresh fruit decay. However, this substance is highly volatile, thermolabile and the direct contact with a food induce undesirable changes in the organoleptic properties. For this reason, the application of EUG represents a big challenger and its encapsulation through inclusion complexes formation with β-cyclodextrin (β-CD) is presented as a solution. In this way, the aim of this work was to develop, characterize and assess the antifungal capacity of inclusion complexes β-CD:EUG. For this, co-precipitation was used as method of inclusion complexes synthesis. The quantity of entrapped EUG was determined by gaseous chromatography. The inclusion complexes were characterized by thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR). Moreover, the antifungal activity was probed in a headspace system. Results showed that the EUG entrapped quantity was of 68,5 mg/g inclusion complexes. Furthermore, the characteristic peaks of EUG did not appear in inclusion complexes TGA thermogram and FTIR spectrum which confirm the effective compound encapsulation. Finally, inclusion complexes inhibited the growing of A. cinerea at 53% and avoided the fungal sporulation. These findings suggest that the β- CD:EUG inclusion complexes are suitable to use in the storage and transportation of fresh fruits to prevent their deterioration. Keywords: Botrytis cinerea, fresh fruits, headspace. Resumen El eugenol (EUG) es el principal componente del aceite esencial de clavo de olor. Éste ha destacado por su efectivo control de Botrytis cinerea, uno de los hongos más importantes que provoca la pudrición de frutas frescas. Sin embargo, esta sustancia es altamente volátil, termolábil y provoca cambios desagradables en las propiedades organolépticas del alimento si está en contacto directo con el mismo, por lo que su aplicación presenta un gran desafío. Ante esto, se propone su encapsulación a través de la formación de complejos de inclusión con β-ciclodextrina (β-CD). En este sentido, el objetivo de la presente investigación fue desarrollar, caracterizar y evaluar la capacidad antifúngica de complejos de inclusión β-CD:EUG. Éstos se sintetizaron mediante el método de co-precipitación, y la cantidad de EUG atrapada en la β-CD fue cuantificada por cromatografía de gases. Los complejos de inclusión se caracterizaron a través de análisis termogravimétrico (TGA) y espectroscospía infrarroja con transformada de Fourier (FTIR). Además, su actividad antifúngica se evaluó en un sistema de espacio de cabeza. Los resultados mostraron que la cantidad de EUG atrapada fue de 68,5 mg/g de complejo de inclusión. Además, en su termograma TGA y espectro FTIR no se observaron los picos característicos del EUG, confirmando la efectiva encapsulación del compuesto. Finalmente, los complejos de inclusión inhibieron el 53% del crecimiento de B. cinerea y evitaron su esporulación. Estos resultados permiten sugerir el uso de complejos de inclusión β-CD:EUG en el almacenamiento y transporte de frutas frescas para prevenir su deterioro. Palabras clave: Botrytis cinerea, frutas frescas, espacio de cabeza

Nitric oxide and L-type calcium channel influences the changes in arterial blood pressure and heart rate induced by central angiotesin II

We study the voltage dependent calcium channels and nitric oxide involvement in angiotensin II-induced pressor effect. The antipressor action of L-Type calcium channel antagonist, nifedipine, has been studied when it was injected into the third ventricle prior to angiotensin II. The influence of nitric oxide on nifedipine antipressor action has also been studied by utilizing NW-nitro-L-arginine methyl ester (LNAME) (40 μg/0.2 μl) a nitric oxide synthase inhibitor and L-arginine (20 μg/0.2 μl), a nitric oxide donor agent. Adult male Holtzman rats weighting 200–250 g, with cannulae implanted into the third ventricle were injected with angiotensin II. Angiotensin II produced an elevation in mean arterial pressure and a decreased in heart rate. Such effects were potentiated by the prior injection of LNAME. L-arginine and nifedipine blocked the effects of angiotensin II. These data showed the involvement of L-Type calcium channel and a free radical gas nitric oxide in the central control of angiotensin II-induced pressor effect. This suggested that L-Type calcium channel of the circunventricular structures of central nervous system participated in both short and long term neuronal actions of ANG II with the influence of nitrergic system

T Cell Priming by Activated Nlrc5-Deficient Dendritic Cells Is Unaffected despite Partially Reduced MHC Class I Levels.

NLRC5, a member of the NOD-like receptor (NLR) protein family, has recently been characterized as the master transcriptional regulator of MHCI molecules in lymphocytes, in which it is highly expressed. However, its role in activated dendritic cells (DCs), which are instrumental to initiate T cell responses, remained elusive. We show in this study that, following stimulation of DCs with inflammatory stimuli, not only did NLRC5 level increase, but also its importance in directing MHCI transcription. Despite markedly reduced mRNA and intracellular H2-K levels, we unexpectedly observed nearly normal H2-K surface display in Nlrc5(-/-) DCs. Importantly, this discrepancy between a strong intracellular and a mild surface defect in H2-K levels was observed also in DCs with H2-K transcription defects independent of Nlrc5. Hence, alongside with demonstrating the importance of NLRC5 in MHCI transcription in activated DCs, we uncover a general mechanism counteracting low MHCI surface expression. In agreement with the decreased amount of neosynthesized MHCI, Nlrc5(-/-) DCs exhibited a defective capacity to display endogenous Ags. However, neither T cell priming by endogenous Ags nor cross-priming ability was substantially affected in activated Nlrc5(-/-) DCs. Altogether, these data show that Nlrc5 deficiency, despite significantly affecting MHCI transcription and Ag display, is not sufficient to hinder T cell activation, underlining the robustness of the T cell priming process by activated DCs

Development of poly(lactic acid) films with propolis as a source of active compounds: biodegradability, physical, and functional properties

Active films (AFs) using poly(lactic acid) (PLA) as a polymeric matrix containing various propolis concentrations (5, 8.5, and 13%) as the active agent (AA) were developed using a casting method. The purpose was to determine the effects of the incorporation of AA on the physical properties of the films and to evaluate the antioxidant and antimicrobial activities. Tensile strength and elastic modulus of the AFs decreased relative to the control (PLA without AA). Introducing the active substances from propolis into the PLA also affected its thermal properties (glass transition). Adding AAs to the polymer generated more opacity with a green-yellowish color compared to the control. In addition, AFs exhibited reduced water vapor permeability as the AA concentration increased. Biodegradation assay showed that the AFs degraded faster than the control. AFs exhibited antioxidant activity, which was measured as the ability to scavenge free radicals (2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonate)), due to the presence of bioactive compounds (phenolics). Antimicrobial activity was evaluated against Escherichia coli and showed a reduction over 4-log cycles. Therefore, incorporation of propolis is a useful strategy for the development of active packaging with antioxidant and antimicrobial effects, which increase the shelf life of food products. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47090.Direccion de Investigacion of Pontificia Universidad Catolica de Valparaiso [DI-037-362-14]University of Santiago de Chile [1555-Vridei O81771GL_CONT

Bases ecofisiológicas da assimilação de carbono e suas implicações na produção de forragem.

essa revisão busca enfatizar os aspectos ecofisiológicos da assimilação do carbono e mostrar como mudanças ambientais podem proporcionar diferentes respostas das plantas. Essas respostas são importantes, pois influenciam diretamente as estratégias de manejo das pastagens e o planejamento da oferta de alimento durante o ano.bitstream/item/117756/1/CNPASA-2014DOC7.pd

Unusual localization of pennella sp. In swordfish (xiphias gladius) hearts

The genus Pennella comprises hematophagous parasites of marine aquatic species, including cephalopods, marine mammals, and pelagic fish. Nine species have been officially included in the genus Pennella plus another six species inquirendae. They are most often found in the host’s musculature, without penetrating internal organs. For the present study, 83 hearts from swordfish (Xiphias gladius) caught in the Mediterranean Sea were sampled and immediately fixed in formalin for histopathological analysis. In total, 10 (12.05%) hearts were found to be parasitized by copepods of the genus Pennella. Macroscopically, there was mild-to-severe fibrinous pericarditis with atrial wall thickening and multiple parasitic nodules. Histologically, the parasitic nodules were surrounded by an inflammatory-necrotizing reaction. Parasitic infestation by Pennella spp. is common in pelagic fish and in swordfish, in particular. Here, however, we report atypical cardiac localization. A future area of focus is the evaluation of cardiac Pennella spp. infestation by histopathology and genetic identification of the parasites

Relative water content in two grass cultivars in crop-livestock system in the State of Tocantins, Brazil.

In this presentation, we report the results of two grasses on Integrated Crop-Livestock System in the Tocantins Cerrado

A fotografia impressa de solares, palácios e quintas no contexto editorial do estado novo: divulgação e promoção de um património artístico português

Pela sua importância e escala, os solares, os palácios e as quintas constituíram importantes objectos de referência com respeito a um tipo particular de habitação doméstica. O seu valor como património artístico e cultural conheceu aproximações e interesses distintos ao longo do século XX. Tendo como referência o período do Estado Novo, a apropriação do tema funcionou na base de uma dupla valorização, enquanto património histórico e artístico e como objecto de interesse turístico. Neste contexto, a fotografia desempenhou um importante papel no modo como permitiu dar a conhecer a arquitectura e os interiores destes edifícios, com uma divulgação significativa na imprensa períodica. Procurava-se por um lado resgatar a identidade destes monumentos nos termos da herança da arquitectura portuguesa, e por outro, enunciar uma estratégia assente na sua conversão como espaços de referência. Tomando como objecto de trabalho as fotografias publicadas dos solares, palácios e quintas em diversas periódicos deste período, o objectivo deste artigo é analisar o papel da fotografia deste património arquitectónico. Mais concretamente, que importância tem este documento e qual a sua relevância do ponto de vista historiográfico? Existe um forte manancial de imagens que, a par do papel de divulgação histórico ou patrimonial, funcionam como reforço de valores nacionais, particularmente com a construção de um ideário de arquitectura portuguesa. Paralelamente, estas permitem documentar os vários períodos da vida dos edifícios, divulgando o trabalho de diferentes orgãos oficiais do estado e a acção dos privados na sua reabilitação e valorização. A hipótese de trabalho radica assim na valorização da fotografia como documento de estudo destes monumentos, em paralelo com as fontes escritas e cartográficas, à qual não tem sido dada a devida relevância por parte da literatura especializada, em particular nos domínios da história de arte e arquitectura. A metodologia de trabalho assenta assim sobre o inventário e sistematização das imagens provenientes de um conjunto de publicações selecionadas, entre elas: a Panorama, Architectura Portuguesa e Eva. A análise destas publicações permitiu constatar um recurso consistente da fotografia, como importante veículo de propaganda, mas também como importante processo documental e historiográfico. É a relação entre estes dois campos que se pretende explorar mais profundamente neste trabalho.info:eu-repo/semantics/submittedVersio