Quantitative Estimation of the Nonstationary Behavior of Neural Spontaneous Activity

The “stationarity time” (ST) of neuronal spontaneous activity signals of rat embryonic cortical cells, measured by means of a planar Multielectrode Array (MEA), was estimated based on the “Detrended Fluctuation Analysis” (DFA). The ST is defined as the mean time interval during which the signal under analysis keeps its statistical characteristics constant. An upgrade on the DFA method is proposed, leading to a more accurate procedure. Strong statistical correlation between the ST, estimated from the Absolute Amplitude of Neural Spontaneous Activity (AANSA) signals and the Mean Interburst Interval (MIB), calculated by classical spike sorting methods applied to the interspike interval time series, was obtained. In consequence, the MIB may be estimated by means of the ST, which further includes relevant biological information arising from basal activity. The results point out that the average ST of MEA signals lies between 2-3 seconds. Furthermore, it was shown that a neural culture presents signals that lead to different statistical behaviors, depending on the relative geometric position of each electrode and the cells. Such behaviors may disclose physiological phenomena, which are possibly associated with different adaptation/facilitation mechanisms

Myocardial stretch-induced compliance is abrogated under ischemic conditions and restored by cGMP/PKG-related pathways

Introduction: Management of acute myocardial infarction (MI) mandates careful optimization of volemia, which can be challenging due to the inherent risk of congestion. Increased myocardial compliance in response to stretching, known as stretch-induced compliance (SIC), has been recently characterized and partly ascribed to cGMP/cGMP-dependent protein kinase (PKG)-related pathways. We hypothesized that SIC would be impaired in MI but restored by activation of PKG, thereby enabling a better response to volume loading in MI.Methods: We conducted experiments in ex vivo rabbit right ventricular papillary muscles under ischemic and non-ischemic conditions as well as pressure–volume hemodynamic evaluations in experimental in vivo MI induced by left anterior descending artery ligation in rats.Results: Acutely stretching muscles ex vivo yielded increased compliance over the next 15 min, but not under ischemic conditions. PKG agonists, but not PKC agonists, were able to partially restore SIC in ischemic muscles. A similar effect was observed with phosphodiesterase-5 inhibitor (PDE5i) sildenafil, which was amplified by joint B-type natriuretic peptide or nitric oxide donor administration. In vivo translation revealed that volume loading after MI only increased cardiac output in rats infused with PDE5i. Contrarily to vehicle, sildenafil-treated rats showed a clear increase in myocardial compliance upon volume loading.Discussion: Our results suggest that ischemia impairs the adaptive myocardial response to acute stretching and that this may be partly prevented by pharmacological manipulation of the cGMP/PKG pathway, namely, with PDE5i. Further studies are warranted to further elucidate the potential of this intervention in the clinical setting of acute myocardial ischemia

Metal-ion zeolites obtained by chemical and mechanochemical methods as Fenton-like catalysts for health applications

One of the critical steps for the development and health applications of inorganic nanoparticles is to exhibit high efficiency without inducing toxicity. In this work, metal-ion zeolites were developed to be used as Fenton-like catalysts for health applications. ZSM-5 and BEA zeolites were modified through chemical and mechanochemical methods to obtain nanomaterials with tuned particle size and texture. Characterization data showed that the modified materials kept the crystal structure although some textural modifications occurred. Upon Mn2+loading, the catalytic behavior was evaluated by Fenton-like reaction using physiological and mild acidic conditions (37 ºC, pH=7.4 and 6.4 and 50 M H2O2), since these conditions are relevant to various pathological environments. MnBEA series showed the best results by Fenton-like reactions, revealing the great potential of metal-zeolite nanomaterials for health applications.V.I. and A.R.B. thank for the PhD grants, UI/BD/152219/2021 and SFRH/BD/141058/2018, respectively. ASM thanks FCT for the Assistant Researcher contract CEECIND/01371/2017 (Embrace Project). This work was supported by FCT (Foundation for Science and Technology, Portugal) by the projects: UIDB/00100/2020. UIDP/00100/2020 and LA/P/0056/2020, CQ/UM (UID/QUI/0686/2020), CEB (UIDB/04469/2020) and LABBELS (LA/P/0029/2020), and Instituto Politécnico de Lisboa (IPL) through Project IPL/2022/ZeoMed ISEL.info:eu-repo/semantics/publishedVersio

Soil chemical attributes in response to tree distance and sun-exposed faces after the implantation of an integrated crop-livestock-forestry system.

EN: The use of trees in integrated crop-livestock-forestry systems (ICLF) allows diversifying production, increasing profitability per area, and providing a higher animal comfort. However, the influence of tree component on soil chemical attributes in this system is still little studied. This study aimed to assess the effect of trees and sun-exposed faces to solar radiation on soil nutrient availability at different distances of tree rows in an integrated crop-livestock-forestry system. This study was carried out in the northern Mato Grosso State, Brazil, in the Cerrado ? Amazon Forest transition region in an ICLF with the tree component formed by three eucalyptus rows. The assessment carried out in the second year of ICLF implantation considered the effect of tree distances (3, 6, 10, and 15 m) on two sun-exposed faces to solar radiation (north and south) on the main soil chemical attributes. Soil sampling was performed at depths of 0?0.05, 0.05?0.10, 0.10?0.20, and 0.20?0.30 m. The results indicated a homogeneity of the average nutrient contents obtained in the north and south-exposed faces, as well as in the comparison of the same distances in both assessed sun-exposed faces. Effects of trees on soil chemical attributes were verified only when an isolated analysis was carried out in the north-exposed face for K and Al contents. For these attributes, the increased distance in the row was associated with a reduction in their contents in the more superficial and deeper layers, respectively. Trees do not significantly affect soil nutrient availability in the first years of ICLF implantation in systems with homogeneity of solar radiation incidence in the sun-exposed faces although there may be discrete nutrient reductions with the distance of trees. | PT-BR: A inserção das árvores em sistemas de integração lavoura, pecuária e floresta (ILPF) permite diversificar a produção, aumentar a rentabilidade por área e proporcionar maior conforto animal. Entretanto, a influência do componente arbóreo sobre os atributos químicos do solo neste sistema ainda é pouco estudada. Neste estudo, objetivou-se avaliar o efeito das árvores e das faces de exposição solar sobre a disponibilidade de nutrientes no solo em diferentes distâncias de renques de árvores em um sistema de integração lavoura pecuária floresta. O trabalho foi realizado no norte do estado do Mato Grosso, em região de transição Cerrado/ Floresta Amazônica em um sistema ILPF com o componente arbóreo formado por renques de três linhas de eucalipto. A avaliação efetuada no segundo ano de implantação do sistema ILPF considerou o efeito da distância das árvores (3, 6, 10 e 15 m) em duas faces de exposição solar (norte e sul) sobre os principais atributos químicos do solo. A amostragem do solo foi efetuada nas profundidades de 0-0,05; 0,05-0,10; 0,10-0,20 e 0,20-0,30 m. Os resultados indicaram homogeneidade dos teores médios de nutrientes obtidos nas faces norte e sul, bem como na comparação das mesmas distâncias nas duas faces de exposição avaliadas. Efeitos das árvores sobre os atributos químicos do solo foram verificados apenas quando da análise isolada na face norte para os teores de K e Al. Para esses atributos, o aumento da distância do renque foi associado à redução dos teores nas camadas mais superficiais e mais profundas, respectivamente. A disponibilidade de nutrientes no solo não é afetada significativamente pelas árvores nos primeiros anos de implantação do sistema ILPF em sistemas em que há homogeneidade na incidência de raios solares nas faces de exposição, ainda que possa reduções discretas de nutrientes com o distanciamento das árvores

Manejo sustentável e nutrição mineral do nim indiano.

O objetivo básico deste trabalho é apresentar algumas informações e procedimentos que devem nortear o planejamento da recomendação de adubação de viveiro, campo, fundamentais na produção de mudas e estabelecimento de povoamentos florestais e avaliação da necessidade de adubação.bitstream/CNPAF/23581/1/comt_110.pd

Resistência a doenças foliares e de frutos em novos híbridos de maracujazeiro.

A lucratividade da cultura do maracujazeiro está intimamente associada à produtividade e qualidade da matéria-prima. Portanto, estas duas características constituem-se nos principais objetivos dos diferentes programas de melhoramento genético da espécie. Dentre as principais doenças que infectam a parte aérea do maracujazeiro, estão à virose do endurecimento dos frutos (causado pelo Cowpea aphid-borne mosaic vírus - CABMV ou Passion fruit woodiness Virus - PWV, ambos Potyvirus), o vírus da pinta verde (Passion fruit green spot virus - PFGSV), a antracnose, verrugose, cladosporiose, mancha parda e septoriose (Ruggiero et al., 1996). Nos últimos anos a fusariose (Fusarium oxysporum f. sp. passiflorae) também tem merecido atenção da pesquisa em função do seu grande poder de destruição das plantas.pdf 133

An insight into the synthesis of cationic porphyrin-imidazole derivatives and their photodynamic inactivation efficiency against Escherichia coli

New porphyrin-imidazole derivatives were synthesised by Radziszewski reaction between 2-formyl-5,10,15,20-tetraphenylporphyrin 1 and several (hetem)aromatic 1,2-diones, which after cationization afforded promising monocationic photosensitizers 3a-d. Singlet oxygen studies have demonstrated that all the cationic porphyrin-imidazole conjugates 3a-d were capable to produce cytotoxic species. These photosensitizers were able to photoinactivate Eschericha coli and their inactivation profile was improved in the presence of KI.The authors are grateful to University of Aveiro and FCT/MCT for the financial support for QOPNA research Unit (FCT UID/QUI/00062/2019), the LAQV-REQUIMTE (UIDB/50006/2020), CESAM (UID/AMB/50017/2019) and CQUM (QUI/UI0686/2018) through national founds and, where applicable, co-financed by the FEDER, within the PT2020 Partnership Agreement, and to the Portuguese NMR Network. The research contract of N.M.M. Moura (REF.-048-88-ARH/2018) is funded by national funds (OE), through FCT - Fundacao para a Ciencia e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19

Caracterização do ciclo estral de vacas e novilhas curraleiras Pé-Duro.

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