Nitrogen and phosphorus additions negatively affect tree species diversity tropical forest regrowth trajectories.

Nutrient enrichment is increasingly affecting many tropical ecosystems, but there is no information on how this affects tree biodiversity. To examine dynamics in vegetation structure and tree species biomass and diversity, we annually remeasured tree species before and for six years after repeated additions of nitrogen (N) and phosphorus (P) in permanent plots of abandoned pasture in Amazonia. Nitrogen and, to a lesser extent, phosphorus addition shifted growth among woody species. Nitrogen stimulated growth of two common pioneer tree species and one common tree species adaptable to both high- and lowlight environments, while P stimulated growth only of the dominant pioneer tree Rollinia exsucca (Annonaceae). Overall, N or P addition reduced tree assemblage evenness and delayed tree species accrual over time, likely due to competitive monopolization of other resources by the few tree species responding to nutrient enrichment with enhanced establishment and/or growth rates. Absolute tree growth rates were elevated for two years after nutrient addition. However, nutrient-induced shifts in relative tree species growth and reduced assemblage evenness persisted for more than three years after nutrient addition, favoring two nutrientresponsive pioneers and one early-secondary tree species. Surprisingly, N þ P effects on tree biomass and species diversity were consistently weaker than N-only and P-only effects, because grass biomass increased dramatically in response to N þ P addition. The resulting intensi?ed competition probably prevented an expected positive N þ P synergy in the tree assemblage. Thus, N or P enrichment may favor unknown tree functional response types, reduce the diversity of coexisting species, and delay species accrual during structurally and functionally complex tropical rainforest secondary succession

Baseline characteristics and risk factors for ulcer, amputation and severe neuropathy in diabetic foot at risk: the brazupa study

CNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOStudies on diabetic foot and its complications involving a significant and representative sample of patients in South American countries are scarce. The main objective of this study was to acquire clinical and epidemiological data on a large cohort of diabetic patients from 19 centers from Brazil and focus on factors that could be associated with the risk of ulcer and amputation. Methods: This study presents cross sectional, Baseline results of the BRAZUPA Study. A total of 1455 patients were included. Parameters recorded included age, gender, ethnicity, diabetes and comorbidity-related records, previous ulcer or amputation, clinical symptomatic score, foot classification and microvascular complications. Results: Patients with ulcer had longer disease duration (17.2 +/- 9.9 vs. 13.2 +/- 9.4 years; p < 0.001), and poorer glycemic control (HbA1c 9.23 +/- 2.03 vs. 8.35 +/- 1.99; p < 0.001). Independent risk factors for ulcer were male gender (OR 1.71; 95 % CI 1.2-3.7), smoking (OR 1.78; 95 % CI 1.09-2.89), neuroischemic foot (OR 20.34; 95 % CI 9.31-44.38), region of origin (higher risk for those from developed regions, OR 2.39; 95 % CI 1.47-3.87), presence of retinopathy (OR 1.68; 95 % CI 1.08-2.62) and absence of vibratory sensation (OR 7.95; 95 % CI 4.65-13.59). Risk factors for amputation were male gender (OR 2.12; 95 % CI 1.2-3.73), type 2 diabetes (OR 3.33; 95 % CI 1.01-11.1), foot at risk classification (higher risk for ischemic foot, OR 19.63; 95 % CI 3.43-112.5), hypertension (lower risk, OR 0.3; 95 % CI 0.14-0.63), region of origin (South/Southeast, OR 2.2; 95 % CI 1.1-4.42), previous history of ulcer (OR 9.66; 95 % CI 4.67-19.98) and altered vibratory sensation (OR 3.46; 95 % CI 1.64-7.33). There was no association between either outcome and ethnicity. Conclusions: Ulcer and amputation rates were high. Age at presentation was low and patients with ulcer presented a higher prevalence of neuropathy compared to ischemic foot at risk. Ischemic disease was more associated with amputations. Ethnical differences were not of great importance in a miscegenated population825CNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOsem informaçã

Agricultural machinery adequacy for handling the mombaça grass biomass in agroforestry systems.

Abstract: The current scenario of Agroforestry Systems (AFS) worldwide lacks specific machinery, resulting in practically all operations being carried out manually. This leads to a significant physical effort for small-scale farmers and limits the implementation of AFS to small areas. The objective of the study was to evaluate the suitability of existing machines for performing agroforestry tasks. This research utilizes Descriptive Statistics and Exponentially Weighted Moving Average methods to evaluate the data and compare the treatments, where different machines are used to cut Mombaça grass (Megathyrsus maximus Jacq): (i) costal brushcutter (CBC); (ii) tractor-mounted rotary brushcutter (RBC); and (iii) mini grain reaper machine (GRM). The experiments were conducted in Jaguariúna, São Paulo, Brazil. GRM is recommended for achieving greater biomass production, reducing raking time, and minimizing operational costs. CBC is suitable for smaller areas due to its affordability and slow operation, which requires significant physical effort. RBC is recommended for reducing working time, physical effort, and personnel costs, making it suitable for larger-scale contexts

O PIBID/Química UEL - Um Relato de Experiência na Escola: Abordando o Tema Radioatividade

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Identification of metabolic pathways influenced by the G-protein coupled receptors GprB and GprD in Aspergillus nidulans

Heterotrimeric G-protein-mediated signaling pathways play a pivotal role in transmembrane signaling in eukaryotes. Our main aim was to identify signaling pathways regulated by A. nidulans GprB and GprD G-protein coupled receptors (GPCRs). When these two null mutant strains were compared to the wild-type strain, the DeltagprB mutant showed an increased protein kinase A (PKA) activity while growing in glucose 1% and during starvation. In contrast, the DeltagprD has a much lower PKA activity upon starvation. Transcriptomics and (1)H NMR-based metabolomics were performed on two single null mutants grown on glucose. We noted modulation in the expression of 11 secondary metabolism gene clusters when the DeltagprB and DeltagprD mutant strains were grown in 1% glucose. Several members of the sterigmatocystin-aflatoxin gene cluster presented down-regulation in both mutant strains. The genes of the NR-PKS monodictyphenone biosynthesis cluster had overall increased mRNA accumulation in DeltagprB, while in the DeltagprD mutant strain the genes had decreased mRNA accumulation. Principal component analysis of the metabolomic data demonstrated that there was a significant metabolite shift in the DeltagprD strain. The (1)H NMR analysis revealed significant expression of essential amino acids with elevated levels in the DeltagprD strain, compared to the wild-type and DeltagprB strains. With the results, we demonstrated the differential expression of a variety of genes related mainly to secondary metabolism, sexual development, stress signaling, and amino acid metabolism. We propose that the absence of GPCRs triggered stress responses at the genetic level. The data suggested an intimate relationship among different G-protein coupled receptors, fine-tune regulation of secondary and amino acid metabolisms, and fungal development