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Abstract Plants exposed to different light intensities generate physiological, morphological, and anatomical changes conducting to plasticity. Thus, this characteristic establishes the ability of plants to present phenotypic adjustments by the same genotype under different environmental conditions. The objective of this study was to verify the morphophysiological alterations in Campomanesia xanthocarpa (Mart.) O. Berg (guabiroba) seedlings cultivated in different shading levels. The seedlings were grown for 21 months under full sun or 30%, 50%, and 80% under shading. Growth, photosynthetic pigments, gas exchange rate, chlorophyll fluorescence, and leaf anatomy were evaluated. In all the treatments subjected to shading, plasticity mechanisms involved structural and physiological changes such as an increase in leaf area and chlorophyll content (total and Chl a), reduction in leaf thickness, and increased gas exchange and quantum yield of photosystem II. The guabiroba seedlings can be cultivated in full sun or different shading environments; even under high shading intensity (80%), the plants showed vigor similar to those produced in a sunny environment. These results confirmed our hypothesis about guabiroba acclimation capacity to shading, noteworthy information for nurseries, orchards, agroforestry systems, or forest restoration in a wide range of light environments.

ABSTRACT The objective of this research was to analyze the differences between the food behaviors observed under the factors of production environment, sex and lighting system, using stochastic tools of multivariate analysis. As for the thermal characteristics of the environment, air temperature (T, °C), enthalpy (H, kJ kg-1), and black globe temperature and humidity index (BGTHI) showed high positive correlation with each other and strong negative correlation with relative humidity (RH, %). The “male drinking” behavior was positively associated with thermal characteristics of the environment in the three periods of the day, that is, the act of drinking more water would be a way to alleviate thermal stress. Birds subjected to red LED showed a strong negative correlation with temperature associated with the “female drinking” behavior, in the afternoon period, according to the principal component analysis, which is justified by the orientation of the broiler house with its longitudinal axis in the NE/SW direction, so the sunlight directly hits the area where the drinker was located. Variation in body weight showed better response when the birds were exposed to a temperature of 27 °C, for the 5th week of the rearing cycle.

ABSTRACT The objective of this research was to evaluate the thermal efficiency of roofs used on individual shelters during milk-feeding stage of Girolando calves. The research was conducted at a farm located in a dry region of Pernambuco state, Brazil. The experimental design was completely randomized, with 27 Holstein × Gir dairy crossbred calves housed in shelters with three roofing materials (fibre cement tile, recycled tile, and thatched roofs). The recycled tiles and thatched roofs provided reductions of 18.7 and 14.6% in radiant thermal load, respectively. Regardless the roofing material, all animals increased their respiratory rate to maintain thermal equilibrium.

RESUMO Este estudo foi conduzido com o objetivo de caracterizar a tipologia das instalações para produção de frangos de corte na região Agreste do Estado de Pernambuco, por meio de levantamento das características construtivas de aviários existentes na região. Foram avaliados 68 galpões, em 27 granjas, no período de maio de 2012 a abril de 2013. Com base nos resultados obtidos, 90% das instalações apresentaram orientação leste - oeste, com pequeno afastamento entre galpões (< 30 m). A maioria dos galpões apresentou cobertura com telhas cerâmicas (93%), ausência de forro (93%) e lanternim (100%), pé-direito abaixo do recomendado (90%), beirais menores que 1,25 m (93%) e muretas com altura superior a 0,2 m (40%). Quanto aos equipamentos, observou-se que a principal fonte de aquecimento foi por campânulas à lenha (71%), comedouros e bebedouros automatizados (46 e 35%) e pendulares (54 e 65%). Aproximadamente, 67% dos galpões possuíam ventiladores e 58% destes estavam associados à nebulização. O levantamento permitiu caracterizar o perfil das instalações e suas necessidades de adequação para a melhoria da condição de alojamento das aves na região.

Erythema elevatum diutinum is a rare neutrophilic dermatosis with vasculitis, which presents as persistent, symmetrical, purple or brownish papules and nodules, mainly in the extensor surface of the limbs. We describe a case of erythema elevatum diutinum and polyarthritis as initial manifestations of Crohn's disea se associated spondyloarthritis. A 51-year-old man, from São Tomé e Príncipe, with previous history of treated tuberculosis and chronic hepatitis B infection, was admitted due to 4 months history of polyarthritis, hyperpigmented papules on the extensor surfaces, occasional episodes of bloody mucous diarrhea and significant weight loss. Histology of the skin showed myeloperoxidase positive neutrophilic granulocytes with moderate karyorrhexis, consistent with erythema elevatum diutinum. Colonoscopy showed erosions in sigmoid and rectum. Diagnosis of erythema elevatum diutinum secondary to Crohn's disease with associated peripheral spondyloarthritis was assumed. The patient was treated with prednisolone, sulphasalazine, metronidazole, azathioprine and tenofovir with good clinical response. As erythema elevatum diutinum can be secondary to multiple systemic diseases, including rheumatic diseases and inflammatory bowel disease, being aware and re - cognizing this entity can be of great importance for rheumatologists. [ABSTRACT FROM AUTHOR]

The activity-regulated cytoskeleton-associated (Arc) protein controls synaptic strength by facilitating AMPA receptor (AMPAR) endocytosis. Here we demonstrate that Arc targets AMPAR to be internalized through a direct interaction with the clathrin-adaptor protein 2 (AP-2). We show that Arc overexpression in dissociated hippocampal neurons obtained from C57BL/6 mouse reduces the density of AMPAR GluA1 subunits at the cell surface and reduces the amplitude and rectification of AMPAR-mediated miniature-EPSCs (mEPSCs). Mutations of Arc, that prevent the AP-2 interaction reduce Arc-mediated endocytosis of GluA1 and abolish the reduction in AMPAR-mediated mEPSC amplitude and rectification. Depletion of the AP-2 subunit µ2 blocks the Arc-mediated reduction in mEPSC amplitude, an effect that is restored by reintroducing µ2. The Arc-AP-2 interaction plays an important role in homeostatic synaptic scaling as the Arc-dependent decrease in mEPSC amplitude, induced by a chronic increase in neuronal activity, is inhibited by AP-2 depletion. These data provide a mechanism to explain how activity-dependent expression of Arc decisively controls the fate of AMPAR at the cell surface and modulates synaptic strength, via the direct interaction with the endocytic clathrin adaptor AP-2.