RESUMO A compactação subsuperficial do solo e o estresse nutricional estão entre os principais fatores que limitam a produtividade dos cultivos agrícolas. A utilização de resíduos de origem florestal, como a cinza de madeira, é uma opção viável na recuperação química de solos, podendo proporcionar desenvolvimento radicular vigoroso em solos com compactação subsuperficial. Nesta pesquisa, objetivou-se indicar a dose de cinza vegetal mais adequada com vistas ao manejo eficiente desse resíduo aplicado em culturas rotacionais cultivadas em solos com compactação subsuperficial. Plantas de cártamo (Carthamus tinctorius), uma cultura de rotação com sistema radicular pivotante profundo, foram cultivadas em solo argiloso adubado com diferentes doses de cinza e com níveis de compactação induzida na camada subsuperficial. O experimento foi conduzido em delineamento experimental em blocos casualizados, sob esquema fatorial 4 × 5, composto por quatro doses de cinza vegetal (8,0; 16,0; 24,0 e 32,0 g dm-3) e cinco níveis de densidade do solo (1,0; 1,2; 1,4; 1,6 e 1,8 kg dm-3), com quatro repetições. As variáveis de crescimento da cultura (altura de plantas, número de folhas, diâmetro do caule e índice de clorofila SPAD) foram avaliadas aos 15, 45 e 75 dias após a emergência. Os resultados indicaram que a compactação foi o fator mais limitante ao desenvolvimento vegetativo do cártamo, independentemente da dose de cinza. A interação entre os fatores dose de cinza de madeira e densidade do solo, quando presente, mostrou que a melhor resposta de crescimento ocorreu para a dose de cinza na ordem de 25 g dm-3 para uma densidade de 1,2 kg dm-3.

ABSTRACT Subsurface soil compaction and nutritional stress are among the main factors that limit the yield of crops. Using forest residues, such as wood ash, is a viable option in the chemical recovery of soils and can promote vigorous root development in soils with subsurface compaction. The objective of this study was to indicate the most adequate dose of wood ash for efficient management of this residue applied in rotational crops cultivated in soils with subsurface compaction. Safflower plants (Carthamus tinctorius), a rotational crop with a deep taproot system, were grown in clay soil fertilized with different doses of ash and with induced levels of compaction in the subsurface layer. The experiment was conducted in a randomized block design, under a 4 × 5 factorial scheme, composed of four doses of wood ash (8.0, 16.0, 24.0, and 32.0 g dm-3) and five levels of soil bulk density (1.0, 1.2, 1.4, 1.6, and 1.8 kg dm-3), with four replicates. Crop growth variables (plant height, number of leaves, stem diameter, and SPAD chlorophyll index) were evaluated at 15, 45, and 75 days after emergence. The results indicated that soil compaction was the most limiting factor to the vegetative development of safflower, regardless of the ash dose. The interaction between the wood ash dose and bulk density, when present, showed that the best growth response occurred for ash dose of 25 g dm-3 for a soil bulk density of 1.2 kg dm-3.

Abstract The aim of this investigation was to study the degradation of tributyl phosphate (TBP) in aqueous solution by heterogeneous photocatalysis (UV-C/TiO2). To perform the investigation, aqueous solutions containing the contaminant were exposed to UV radiation in the absence or presence of TiO2 in suspension or supported on a Fe-Cr metal alloy plate. TBP analyses before and after the treatment were performed by Ultra-Performance Liquid Chromatography (UPLC) in order to quantify the contaminant degradation. The results showed that the TiO2 photocatalytic system was able to remove TBP from the solution and the formation of some by-products was observed. TiO2 photocatalytic systems were able to reduce acute toxicity in an Artemia Salina bioassay according to the increase in LC50 from 10.2 ± 0.5%(v/v) to 16.9 ± 0.6 %(v/v) for the immobilized system and to levels which were not possible to detect by the applied method any more for the suspension system.

Chagas' disease is a parasitic disease with unsatisfactory treatment, mainly in chronic stage. This study aimed to evaluate the trypanocidal activity and action mechanisms of α/β-amyrin and its semi-synthetic derivatives, together with four isolated natural triterpenes, tested against trypomastigote and amastigote forms. The structure-activity relationship was suggested and cytotoxicity was measured. In general, greater polar compounds may have improved the selectivity to the protozoan. Action mechanisms were only performed for the amastigotes of Trypanosoma cruzi by evaluating the ultrastructural alterations, membrane permeability, mitochondrial membrane potential and cell volume, since the majority of compounds displayed promising antiamastigote activities. Triterpenes promoted changes on mitochondrial membrane potential and ultrastructural features that suggest autophagy processes. Both combinations between α/β-amyrin and 3-O-acetyl-11-oxo-α/β-amyrin and 3-O-acetyl-α/β-amyrin with benznidazole displayed synergistic effects against amastigotes and antagonistic effects on LLCMK2 cells. The antiamastigote activities, chemical derivatization, drug combinations and action mechanisms revealed to be crucial approaches toward this chronic disease.

RESUMO Os escorpiões de interesse médico no Brasil pertencem ao gênero Tityus. Dentre eles, Tityus stigmurus é o principal responsável por picadas de escorpião na região Nordeste. Após uma picada, a peçonha de escorpião se distribui rapidamente para os órgãos, atingindo os rins depressa. Entretanto, há poucos trabalhos sobre fisiopatologia renal do envenenamento por escorpiões. Neste trabalho, avaliamos os efeitos da peçonha de T. stigmurus (TsV) sobre parâmetros renais em rins de ratos isolados. Ratos Wistar (n = 6), pesando 250-300 g, foram perfundidos com solução de Krebs-Henseleit contendo 6 g/100 mL de albumina de soro bovino. TsV nas concentrações de 0,3 e 1,0 μg/mL foi testado e os efeitos sobre a pressão de perfusão (PP), resistência vascular renal (RVR), fluxo urinário (FU), taxa de filtração glomerular (TFG) e excreção de eletrólitos foram analisados. Apenas na concentração de 1,0 μg/mL de TsV foram observados efeitos que aumentaram PP (controlePP40' = 92,7 ± 1,95; TsVPP40' = 182,0 ± 4,70 mmHg*, *p < 0,05), RVR (controleRVR40' = 3,28 ± 0,23 mmHg; TstRVR40' = 6,76 ± 0,45 mmHg*, *p < 0,05), FU (controleFU50' = 0,16 ± 0,04; TstFU50' = 0,60 ± 0,10 mL/g/min*, *p < 0,05), a TFG e excreção de eletrólitos, com alterações histológicas que indicam de lesão renal tubular. Em conclusão, peçonha de T. stigmurus induz um aumento transiente da PP com lesão tubular, ambos os quais conduzem a uma excreção elevada de eletrólitos.

ABSTRACT Scorpions belonging to the Tityus genus are of medical interest in Brazil. Among them, Tityus stigmurus is the main scorpion responsible for stings in the Northeast region. After a sting, the scorpion venom distributes rapidly to the organs, reaching the kidneys quickly. However, there are few studies concerning the renal pathophysiology of scorpion poisoning. In this study, we evaluated the effects of T. stigmurus venom (TsV) on renal parameters in isolated rat kidneys. Wistar rats (n = 6), weighing 250-300 g, were perfused with Krebs-Henseleit solution containing 6 g/100 mL bovine serum albumin. TsV at 0.3 and 1.0 μg/mL was tested, and the effects on perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), and electrolyte excretion were analyzed. Effects were observed only at TsV concentration of 1.0 μg/mL, which increased PP (controlPP40' = 92.7 ± 1.95; TsVPP40' = 182.0 ± 4.70* mmHg, *p < 0.05), RVR (controlRVR40' = 3.28 ± 0.23 mmHg; TstRVR40' = 6.76 ± 0.45* mmHg, *p < 0.05), UF (controlUF50' = 0.16 ± 0.04; TstUF50' = 0.60 ± 0.10* mL/g/min,*p < 0.05), GFR and electrolyte excretion, with histological changes that indicate renal tubular injury. In conclusion, T. stigmurus venom induces a transient increase in PP with tubular injury, both of which lead to an augmented electrolyte excretion.

The continuous search for antimicrobial candidates pushes the pursuit of compounds in the most diverse organisms. Amphibians are known as a prolific source of antibacterial peptides. Based on the rich biodiversity of the Amazon region the unexplored green-tree frog (Hypsiboas cinerascens) was studied for its skin secretion peptide content. Chromatographic separations and established tandem mass spectrometry (MS/MS) methods were used for sequencing the primary structures of the purified compounds. De novo sequencing lead to the identification of five new peptides related to hylaseptin P1, displaying an aminated C-terminal. Sequencing of the complementary deoxyribonucleic acid (cDNA) analysis allowed the disambiguation of isobaric amino-acids for C-01. Matrix assisted laser desorption ionization (MALDI) was carried out, demonstrating the in situ co-occurrence of the identified peptides in the dorsal skin. The major peptide C-01 was synthesized and assayed against a selection of microorganisms displaying minimal inhibitory concentrations (MICs) ranging from 4 to 16 µM.

The development of new materials based on industrial wastes has been the focus of much research for a sustainable world. The growing demand for tyres has been every year exacerbating environmental problems due to indiscriminate disposal in the nature, making a potentially harmful waste to public health. The incorporation of rubber particles from scrap tyres into polymeric composites has achieved high toughness and moderate mechanical properties. This work investigates the geometric effects (thickness, width and internal cell angle) of auxetic structures made of recycled rubber composites based on experimental and numerical data. The response surface models integrated with the swarm intelligence and finite element analysis were proposed in order to obtain a range of solutions that provides useful information to the user during the selection of geometric parameters for reentrant cells. The results revealed the cell thickness ranges from 39-40 mm and 5.98-6 mm, and the cell angle range from -0.01 to -0.06º maximize the ultimate strength. The same parameters were able to optimize the modulus of elasticity of rubber auxetic structures, excepting for the angle factor which must be set between -30º and 27.7º. The optimal Poisson's ratio was found when the cell angle ranged from -30º to -28.5º, cell width ranged from 5-5.6 mm and 2 mm in thickness.

El presente artículo sintetiza una perspectiva sociocultural de la competitividad, como resultado del trabajo de investigación aplicada en ejercicios de asesoría a gobiernos municipales, específicamente en Palmira y Buenaventura que hizo el Grupo de Investigación en Negocios Internacionales y Comercio Exterior, en alianza con el Instituto de Prospectiva, Innovación y Gestión del Conocimiento de la Universidad del Valle. Esta perspectiva se materializa en un esquema metodológico que parte de la realización de un perfil competitivo regional, identifica núcleos temáticos que facilitan la profundización de las problemáticas y el tratamiento de las mismas y define un escenario óptimo para la construcción consensuada de estrategias de desarrollo. En su aplicación ha sido posible comprobar que tanto los núcleos temáticos como las categorías de los problemas identificados resultaron comunes en ambos municipios en sus componentes más genéricos. A pesar del carácter heterogéneo de las experiencias, ha sido posible formular un conjunto de estrategias indispensables en las agendas de desarrollo local para municipios similares en los países en desarrollo. Este artículo constituye un aporte fundamental al conjunto de experiencias de construcción de procesos de desarrollo regional con base en el reconocimiento de las particularidades de una localidad

This article summarizes a sociocultural perspective of competitiveness as a result of applied work performed by the Research Group in International Business and Foreign Trade, in partnership with the Foresight, Innovation, and Knowledge Management Institute at Universidad del Valle, in consultation exercises for municipal governments, specifically in Palmira and Buenaventura (Colombia). This perspective becomes practical in a methodology that begins with the creation of a regional competitive profile, continues with the definition of thematic groups identified to facilitate further delving into and treatment of regional competitiveness problems and defines an optimal setting for consensus building strategies. In its application, it has been possible to verify that the theme and types of problems identified were generically common in both municipalities. Despite the heterogeneous nature of the experiences, it was possible to formulate a set of indispensable strategies in the Local Development Agendas for similar municipalities in developing countries. This article is a fundamental contribution to the whole experience of building regional development processes based on recognizing the particular characteristics of the location

Cet article synthétise une perspective socio culturelle de la compétitivité, résultat du travail de recherche appliquée sur des exercices de conseil aux gouvernements des municipalités, spécifiquement à Palmira et à Buenaventura, développée par le Groupe de Recherche en Affaires Internationales et Commerce Extérieur, en alliance avec l'Institut de Prospective, Innovation et Gestion de la Connaissance de l'Université del Valle. Cette perspective se matérialise sur un schéma méthodologique qui part de la réalisation d'un profil compétitif régional, qui identifie les noyaux thématiques qui favorisent l'approfondissement des problématiques et le traitement de celles-ci, et définit un scénario optimal pour la construction consensuelle de stratégies de développement. Avec son application, il a été possible de vérifier que tant les noyaux thématiques comme les catégories des problèmes identifiés ont été communs pour les deux municipalités dans ses composants plus génériques. Malgré le caractère hétérogène des expériences, il a été possible de formuler un ensemble de stratégies indispensables pour les agendas de développement local des municipalités similaires dans le pays en développement. Cet article constitue un apport fondamental pour l'ensemble d'expériences de construction de processus de développement régional sur la base de la reconnaissance des particularités d'une localité