Suchergebnisse

É possível que o equilíbrio da biosfera esteja sendo modificado pelas mudanças globais de origem natural e/ou antrópica. Esta pesquisa teve como objetivo avaliar a variação sazonal dos atributos químicos do solo em uma floresta amazônica. As amostragens do solo foram realizadas nos períodos chuvoso, de transição e menos chuvoso, em parcela de exclusão de água de experimento do Projeto Seca Floresta (ESECAFLOR) e na parcela 13 do plote do Programa de Pesquisa em Biodiversidade (PPBio) (área controle), na FLONA Caxiuanã (Pará). As amostras de solo para as análises químicas e para a determinação da umidade atual do solo foram coletadas nas profundidades de 0-5, 5-10 e 10-20 cm, com auxílio de trado holandês. Os maiores teores dos nutrientes foram encontrados na área do PPBio. Foi identificada diferença significativa entre as áreas, exceto para o magnésio, e entre a soma de bases. Houve diferença significativa entre os períodos sazonais no ESECAFLOR somente para o pH e para a saturação por bases, e no PPBio somente para o sódio. Também houve variação vertical em ambas as áreas. A área do ESECAFLOR apresentou as menores concentrações para a maioria dos nutrientes estudados, evidenciando a influência do processo de exclusão das águas pluviais na disponibilidade desses elementos no solo.

The objective of this study was to assess forage production in a natural grassland by applying different doses of limestone and phosphorus, and the influence of these applications on soil profile. The treatments consisted of the application of limestone doses of 0.0, 7.2, and 14.4 t ha-1 and phosphorus doses of 0,35, 70, and 140 kg of P2O5 ha-1 on the soil surface. The experiment was conducted in a randomized complete block design with split-plots and three replications. The limestone doses were distributed in the main plot and applied only at the beginning of the experiment, whereas the phosphorus doses were distributed in the subplots with subsequent annual maintenance applications. Was used a ruler (cm) for monitoring the growth of pastures and, when grasses reached an average height of 20 cm, forage samples were collected in each subplot and botanical and morphological components were separated and dried until a constant weight was achieved. In the third and fourth assessment years, soil samples were collected in the 0-5, 5-10, 10-15, and 15-20-cm layers to evaluate the influence of treatments on the chemical properties of the soil. The variables analyzed were related to the production of several components, including fodder, native grasses, leguminous plants, unwanted plants, and dead material, in addition to soil properties such as pH, exchangeable aluminum concentration, and base saturation. There was no interaction between the limestone and phosphorus treatments. The effect of limestone doses on forage production was assessed in the third year, and, in the following year, the intermediate dose of limestone (7.2 t ha-1) produced the highest yield (2,316.1 kg of dry matter [DM] of forage ha-1). The increase in phosphorus doses increased forage production in the second year, and reached yields of up to 2,232 Kg DM ha-1 in the fourth year. In summary, the production of natural pastures was enhanced by the application of 25% of the recommended dose of limestone (7.2 t ha-1), and by the application of 50% of the recommended dose of phosphorus (70 kg P2O5 ha-1). The increase in limestone doses directly affected the chemical properties of the soil by decreasing acidity and exchangeable aluminum, and increasing base saturation, even in deeper layers (0-20 cm). The increase in phosphorus doses did not increase the mobility of this nutrient in the deeper layers of the soil (10-20 cm), and the effects were restricted to a depth of up to 10 cm.

Natural pastures are important ecosystems that both contribute to biodiversity conservation and provide an important source of income, especially for cattle ranchers. While these pastures yield fairly low productivity, they can be improved by increasing soil fertility and introducing species with high productive potentials. In this sense, the purpose of this study was to evaluate the effects of applying limestone and phosphorus, as well as introducing cool-season species with a mixture of species dominated by Schizachyrium tenerum Nees, into a natural pasture in the Catarinense Plateau. The experiment was conducted from January 2010 to December 2013; the treatments consisted of superficial distribution of limestone in proportions of 3.6, 7.2, 11.0, and 14.4 t ha-1, as well as distribution of phosphorus in the form of triple superphosphate in proportions of 35, 70, 105, and 140 kg of P2O5 ha-1. In addition, cool-season species were overseeded. The experiment consisted of a randomized block design with subdivided plots and three replications. Limestone was applied to the main parcel, whereas phosphorus was applied to the subplots. There was no interaction between the levels of limestone and phosphorus. The application of 11.0 t ha-1 of limestone yielded the highest forage production, with 3,932.2 kg of dry matter (DM) ha-1 during the second year. Red clover was the species that best reacted to the additions, with levels of 7.2 and 11.0 t ha-1 over the 4 years. In addition, phosphorus provoked a positive response throughout the experiment. The highest forage production was observed during the second year, with an addition of 140 kg P2O5 ha-1 (4,419.4 kg DM ha-1). Only one-eighth of the recommended amount of limestone (3.6 t ha-1) allowed for the establishment and persistence of the legumes introduced into natural pastures. These additions, associated with increasing levels of phosphorus, yielded linear growth in the production of forage in natural pastures with a mixture of species dominated by Schizachyrium tenerum Nees.

Este estudo se propõe a conhecer os significados do encarceramento, bem como as estratégias de enfrentamento com ênfase na resiliência. A metodologia baseia-se na abordagem qualitativa à luz da técnica de História Oral Temática. As falas revelam a prisão enquanto processo de 'mutilação do eu'. A morte civil, a substituição do convívio familiar, o vazio de ordem emocional e material, e a ausência da autonomia caracterizam o significado do cárcere. As estratégias de enfrentamento com resiliência dentro do cotidiano prisional foram a fé, o amor aos filhos, o trabalho, a música e a espera pela liberdade. É preciso que a prisão se comporte para além do caráter punitivo e proporcione cuidados especializados à mulher encarcerada.

Studies of heavy metals adsorption in soil play a key role in predicting environmental susceptibility to contamination by toxic elements. The objective of this study was to evaluate cadmium (Cd) and copper (Cu) adsorption in surface and subsurface soil. Samples of six soils: Xanthic Hapludox (XH1 and XH2), Typic Hapludox (TH), Typic Rhodudalf (TR), Typic Fluvaquent (TF), and Amazonian dark earths (ADE) from Eastern Amazonian, Brazil. The soils were selected for chemical, physical and mineralogical characterization and to determine the adsorption by Langmuir and Freundlich isotherms. All soils characterized as kaolinitic, and among them, XH1 and XH2 showed the lowest fertility. The Langmuir and Freundlich isotherms revealed a higher Cu (H curve) than Cd (L curve) adsorption. Parameters of Langmuir and Freundlich isotherms indicate that soils TR, TF and ADE has the greatest capacity and affinity for metal adsorption. Correlation between the curve adsorption parameters and the soil attributes indicates that the pH, CEC, OM and MnO variables had the best influence on metal retention. The Langmuir and Freundlich isotherms satisfactorily described Cu and Cd soil adsorption, where TR, TF and ADE has a lower vulnerability to metal input to the environment. Besides the pH, CEC and OM the MnO had a significant effect on Cu and Cd adsorption in Amazon soils.

Aims: the present study aimed to investigate the association between indicatives of stress, anxiety and depression with life satisfaction and purpose in life among Brazilian older adults.Methods: this cross-sectional study was conducted with 654 Brazilian older adults who responded the Life Satisfaction Scale, Purpose in Life Scale, Perceived Stress Scale, Geriatric Anxiety Inventory and the Geriatric Depression Scale. Data were analyzed through independent t-test, Cohen's D, Pearson Correlations and Multivariate Regression Analysis (p<0.05).Results: results indicated slightly higher levels of stress and anxiety for women when compared to men (p<0.05); indicatives of stress, anxiety and depression were inversely correlated to life satisfaction and purpose (r = -0.19 to -0.44; p<0.05); stress (β=-0.29) and depression (β=-0.36) were significant predictors of life satisfaction (R2=0.31; p<0.01), and life purpose (R2=0.18; p<0.01) was predicted by stress (β=-0.15), anxiety (β=0.10) and depression (β=-0.39).Conclusion: It can be concluded that stress and depression are significant factors hindering older adults' satisfaction and purpose in life.

The objective of this study was to analyze the effects of anthelmintic treatment and supplementation of post-weaning Nellore calves. The parasitism degree, hematological changes and animal performance were analyzed, as well as the financial viability. One hundred contemporary Nellore calves were used. Animals were divided into four groups: CS+AT: supplementation with concentrate and anthelmintic treatment; CS: supplementation with concentrate; PS+AT: protein mineral supplementation and anthelmintic treatment; PS: protein mineral supplementation. Coproparasitological, hematological, and cost examinations were performed, and productive performance was also evaluated. A completely randomized design was used. Animals that received CS+AT showed greater weight gain. In females, there was significant difference in egg counts per gram of feces only between the CS and PS+AT. In males, animals receiving CS+AT, CS, and PS+AT differ from those receiving PS. No significant effects were observed for total plasma protein, packed cell volume, and eosinophils count. Females which received PS+AT and males who received CS+AT showed higher profitability. This study concludes that effective anthelmintic use is still viable, with higher profitability associated with concentrated supplementation in males, and mineral protein supplementation in females. Male calves show better return over investment when compared to females, due to the higher market value and higher potential performance.

Os animais domésticos são colonizados por uma extensa diversidade de bactérias comensais e patogênicas. Particularmente, os de estimação têm sido apontados como reservatórios de algumas bactérias específicas, como Salmonella spp. e Clostridioides (Clostridium) difficile. Esses animais também podem estar infectados por helmintos potencialmente zoonóticos. No entanto, pouco se sabe sobre os fatores de risco e frequência desses patógenos em cães no Brasil. O objetivo neste estudo foi avaliar a presença de Salmonella spp., C. difficile e helmintos com potencial zoonótico em cães no município de Barra (Bahia, Brasil), bem como fatores de risco associados à ocorrência de diarreia. Para isso, foram obtidas as fezes de 40 cães. Cada tutor respondeu a um questionário epidemiológico para identificar episódios anteriores de diarreia nos animais e fatores de risco associados à presença dos patógenos avaliados. Ancylostoma spp. foi detectado em cinco cães (12,5%), enquanto Salmonella spp. foi isolado em 12,5% dos animais. C. difficile não foi isolado neste estudo. A presença de Ancylostoma spp. foi associada a fezes secas e ausência de vermifugação por mais de 12 meses. Cães positivos para Salmonella spp. foram cinco vezes mais propensos a ter diarreia do que aqueles negativos para este patógeno. Animais alimentados com dieta à base de carne crua e em contato com outros animais apresentaram maior probabilidade de apresentar episódio de diarreia nos últimos 12 meses. Pela primeira vez, Salmonella enterica sorovar Oranienburg foi isolado em um cão. Este trabalho sugere que se deve dar atenção à alimentação dos cães e à desparasitação regular para mitigar os riscos impostos por estes dois patógenos zoonóticos.

Honey from the Apis mellifera bee (Hymenoptera, Apidae) is one of the most consumed beehive products in the world, mainly due to its nutritional and therapeutic value. In poorer regions, its commercialization can be an essential source of income for families and communities. However, the quality of honey can change both during harvesting and processing, as well as by climatic conditionsand the type of vegetation. Therefore, implementing good production practices, with quality control in collection and processing, can add value to this product, promoting the development of the region in which it is produced. Thus, the objectives of this work were to characterize the honey of Africanized honeybees produced in the Eastern Amazon region in the cities of Nova Olinda do Maranhão(NO), Santa Luzia do Paruá (SL) and verify its correlation with a commercial honey sample (CH) – from São Luiz-MA. The physicochemical properties (color, moisture, solids insoluble in water, minerals, and ash, hydroxymethylfurfural, acidity, anddiastatic activity) were analyzed according to the methods of CODEX Alimentarius and the Association of Official Analytical Chemists, and these data were evaluated by the Principal Component Analysis (PCA). The results showed that commercial honey presented higher levels of insoluble solids, HMF, minerals, and ash than samples from NO and SL. Variables that differentiated NO and SL honey were HMF, moisture, and diastase index. Although the samples have different characteristics, the data comply with Brazilian legislation, which can strengthen the development of apiculture in the region.

Context. The Centaur (10199) Chariklo has the first ring system discovered around a small object. It was first observed using stellar occultation in 2013. Stellar occultations allow sizes and shapes to be determined with kilometre accuracy, and provide the characteristics of the occulting object and its vicinity. Aims. Using stellar occultations observed between 2017 and 2020, our aim is to constrain the physical parameters of Chariklo and its rings. We also determine the structure of the rings, and obtain precise astrometrical positions of Chariklo. Methods. We predicted and organised several observational campaigns of stellar occultations by Chariklo. Occultation light curves were measured from the datasets, from which ingress and egress times, and the ring widths and opacity values were obtained. These measurements, combined with results from previous works, allow us to obtain significant constraints on Chariklo's shape and ring structure. Results. We characterise Chariklo's ring system (C1R and C2R), and obtain radii and pole orientations that are consistent with, but more accurate than, results from previous occultations. We confirm the detection of W-shaped structures within C1R and an evident variation in radial width. The observed width ranges between 4.8 and 9.1 km with a mean value of 6.5 km. One dual observation (visible and red) does not reveal any differences in the C1R opacity profiles, indicating a ring particle size larger than a few microns. The C1R ring eccentricity is found to be smaller than 0.022 (3 sigma), and its width variations may indicate an eccentricity higher than similar to 0.005. We fit a tri-axial shape to Chariklo's detections over 11 occultations, and determine that Chariklo is consistent with an ellipsoid with semi-axes of 143.8(-1.5)(+1.4), 135.2(-2.8)(+1.4), and 99.1(-2.7)(+5.4) km. Ultimately, we provided seven astrometric positions at a milliarcsecond accuracy level, based on Gaia EDR3, and use it to improve Chariklo's ephemeris. ; European Research Council under the European Community's H2020 669416 Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) Fundacao de Apoio a Pesquisa do Distrito Federal (FAPDF) 465376/2014-2 European Union H2020-MSCA-ITN-2019 860470 Novo Nordisk Foundation Interdisciplinary Synergy Programme NNF19OC0057374 Fonds de la Recherche Scientifique - FNRS PDR T.0120.21 Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) BEM 150612/2020-6 FB-R 314772/2020-0 RV-M 304544/2017-f5 401903/2016-8 JIBC 308150/2016-3 305917/20196 MA 427700/2018-3 ; Versión aceptada para publicar - Postprint