Higher occupational attainment has previously been associated with increased Alzheimer's disease (AD) neuropathology when individuals are matched for cognitive function, indicating occupation could provide cognitive reserve. We examined whether occupational complexity (OCC) associates with decreased hippocampal volume and increased whole-brain atrophy given comparable cognitive function in middle-aged adults at risk for AD. Participants (n = 323) underwent structural MRI, cognitive evaluation, and work history assessment. Three complexity ratings (work with data, people, and things) were obtained, averaged across up to 3 reported jobs, weighted by years per job, and summed to create a composite OCC rating. Greater OCC was associated with decreased hippocampal volume and increased whole-brain atrophy when matched for cognitive function; results remained substantively unchanged after adjusting for several demographic, AD risk, vascular, mental health, and socioeconomic characteristics. These findings suggest that, in people at risk for AD, OCC may confer resilience to the adverse effects of neuropathology on cognition.

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Objective To examine cross-sectionally whether higher cardiorespiratory fitness (CRF) might favorably modify amyloid-β (Aβ)-related decrements in cognition in a cohort of late-middle-aged adults at risk for Alzheimer's disease (AD). Methods Sixty-nine enrollees in the Wisconsin Registry for Alzheimer's Prevention participated in this study. They completed a comprehensive neuropsychological exam, underwent 11C Pittsburgh Compound B (PiB)-PET imaging, and performed a graded treadmill exercise test to volitional exhaustion. Peak oxygen consumption (VO2peak) during the exercise test was used as the index of CRF. Forty-five participants also underwent lumbar puncture for collection of cerebrospinal fluid (CSF) samples, from which Aβ42 was immunoassayed. Covariate-adjusted regression analyses were used to test whether the association between Aβ and cognition was modified by CRF. Results There were significant VO2peak*PiB-PET interactions for Immediate Memory (p= .041) and Verbal Learning & Memory (p= .025). There were also significant VO2peak*CSF Aβ42 interactions for Immediate Memory (p<.001) and Verbal Learning & Memory (p <.001). Specifically, in the context of high Aβ burden—i.e., increased PiB-PET binding or reduced CSF Aβ42—individuals with higher CRF exhibited significantly better cognition compared with individuals with lower CRF. Conclusion In a late-middle-aged, at-risk cohort, higher CRF is associated with a diminution of Aβ-related effects on cognition. These findings suggest that exercise might play an important role in the prevention of AD.

Purpose The mineralization/immobilization of nutrients from the crop residues is correlated with the quality of the plant material and carbon compartments in the recalcitrant and labile soil fractions. The objective of this study was to correlate the quality and quantity of crop residues incubated in the soil with carbon compartments and CO 2 -C emission, using multivariate analysis. Materials and methods The experiment was conducted in factorial 4 + 2 + 5 with three replicates, referring to three types of residues (control, sugarcane, Brachiaria, and soybean), and two contributions of the crop residues in constant rate, CR (10 Mg ha −1 residue), and agronomic rate, AR (20, 8, and 5 Mg ha −1 residue, respectively, for sugarcane, soybean, and Brachiaria), evaluated five times (1, 3, 6, 12, and 48 days after incubation). At each time, we determined the CO 2 -C emission, nitrogen and organic carbon in the soil, and the residues. In addition, the microbial biomass and water-soluble, labile, and humic substance carbons fractionated into fulvic acids, humic acids and humin were quantified.Results and discussion Higher CO 2 -C emissions occurred in the soil with added residue ranging from 0.5 to 1.1 g CO 2 -C m −2 h −1 in the first 6 days of incubation, and there was a positive correlation with the less labile organic soil fractions as well as residue type. In the final period, after 12 days of soil incubation, there was a higher relation of CO 2 -C emission with carbon humin. The sugarcane and soybean residue (20 Mg ha −1 ) promoted higher CO 2 -C emission and the reduction of carbon residue. The addition of residue contributed to an 82.32 % increase in the emission of CO 2 -C, being more significant in the residue with higher nitrogen availability. Conclusions This study shows that the quality and quantity of residue added to soil affects the carbon sequestration and CO 2 -C emission. In the first 6 days of incubation, there was a higher CO 2 -C emission ratio which correlates with the less stable soil carbon compartments as well as residue. In the final period of incubation, there is no effect of quality and quantity of residue added to soil on the CO 2 -C emission.

Purpose Organomineral fertilizers formulated from different organic sources have been studied for the fertilization of several crops. Filter cake is currently one of the most used sources of organic matter; however, sewage sludge also presents characteristics of agronomic interest, being one of the major environmental problems in Brazil. In this sense, the efficiency of pelletized organomineral fertilizers produced with both sources were evaluated for the development of soybean under different fertilization levels. Methods The experiment was carried out in greenhouse conditions. The soil was characterized as Red Eutrophic Oxisol. The experimental design was randomized block design in a 2 × 4 + 2 factorial scheme, corresponding to two sources of organic matter (sugarcane filter cake and treated sewage sludge), in four doses (50, 75, 100 and 125% of recommendation for soybean cultivation), as well as a mineral fertilization and no-fertilization treatments. The plant development was evaluated (stem diameter, plant height and chlorophylls a and b) at 30, 60 and 90 days after sowing. Results Organomineral fertilizers formulated from sanitized sewage sludge or sugarcane filter cake promote a higher soybean plant height in relation to mineral fertilizer, especially after the middle of the crop cycle. The level of fertilization referring to 75% of the recommended dose for soybean, when made with sanitized sewage sludge or filter cake, resulted in large stem diameter in relation to mineral fertilization. Conclusion Organomineral fertilizers based on sanitized sewage sludge or filter cake promote increases in soybean characteristics up to 90 days.

Nitrification inhibitors (NIs), DCD (dicyandiamide), and DMPP (3,4‐dimethylpyrazole phosphate), in combination with urea (UR) and ammonium sulfate nitrate (ASN) fertilizers were studied under contrasting soil textures (sand, loam, and clay) from cultivated soils collected in Brazil and Germany. Soil samples were incubated over 50 days and the content of ammonium ( N - NH4 + ), nitrate ( N - NO3 - ), and soil pH were measured periodically. Applied NIs delayed the nitrification process across all soil textures. Correlation analysis indicated that combining ASN with NIs resulted in higher NH4 + content and efficiency in delaying the nitrification process with high N‐conversion rate (r = –0.82). The combination of ASN+ DMPP increased the efficiency of the N‐conversion rate (r = –0.86) due to H+ release in soil, while UR+DCD (r = –0.50) had an efficiency of the N‐conversion rate similar to UR (r = –0.42). All the NIs had a better performance in reducing N - NO3 - formation in sandy soils as compared to the loam and clay textured soils. Use of DMPP with an N fertilizer results in a soil pH decrease and can be an option to increase the efficiency of the N‐conversion rate, reducing N losses in soil. Overall, our results suggest that NIs have a better performance in reducing N - NO3 - formation in sandy soils as compared to that of the loam and clay textured soils. Use of DMPP with ASN results in a soil pH decrease and can be an option to reduce N losses in soil.

-Yellow passion fruit has conquered a significant position in the agribusiness of tropical fruits; therefore, farmers have been interested in expanding their groves, and technical information that guarantees the high yield of the farmings is needed. Aiming to observe factors related to the propagative material targeted at quality and maximization of the genetic potential, the objective of the study consisted in assessing germination and emergence of passion fruit seeds collected in three positions in the fruits and submitted to different methods of mucilage removal (aryl). The passion fruits were split in three parts: distal, medial and proximal and the contents of each part was divided in two. The content of each part of the fruit was submitted to mechanical and by fermentation methods for removal of aryl. It is concluded that the seed position in the fruit does not interferes with the germination. The aryl removal method by mechanical extraction affects the germination and seedling emergence.Index terms: Passiflora edulis, mechanical extraction, fermentation, propagation, mucilage. Métodos de remoção do arilo e posições das sementes no fruto de maracujá:Germinação e emergência RESUMO -O maracujá-amarelo conquistou significativa posição no agronegócio de frutas tropicais, com isso, produtores despertaram interesse para expandir seus pomares, sendo necessárias informações técnicas que garantam a alta produtividade das lavouras. No intuito de observar fatores relacionados ao material propagativo visando a qualidade e a maximização do potencial genético objetivou-se avaliar a germinação e a emergência de sementes de maracujá coletadas em três posições nos frutos e submetidas a métodos de retirada da mucilagem (arilo). Os frutos de maracujá foram seccionados em três partes: distal, mediana e proximal. Cada um destes conteúdos foi submetido aos métodos mecânico e de fermentação para remoção do arilo. Podendo concluir que a posição da semente no fruto do maracujazeiro não interfere na germinação e o método de remoção do arilo por extração mecânica prejudica a germinação e a emergência de plântulas.Termos para indexação: Passiflora edulis, extração mecânica, fermentação, propagação, mucilagem.

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