Design of concrete-filled steel tubular columns under axial loading according to NBR 8800:2008 and Eurocode 4:2004: tests results and comparisons

São apresentados os resultados experimentais de 32 pilares mistos preenchidos de seção circular, submetidos à compressão axial, para os quais foi avaliada a influência dos seguintes parâmetros: resistência à compressão do concreto, relação comprimento/diâmetro (L/D) e espessura do tubo de aço (t). Os valores experimentais de força máxima foram comparados com aqueles resultantes da aplicação da formulação apresentada na NBR 8800:2008 e no EN 1994-1-1:2004 (Eurocode 4 - EC4), extrapolando-se os resultados para valores de resistência do concreto não previstos por essas normas. Os perfis de aço com relação comprimento/diâmetro (L/D) de 3, 5, 7 e 10 foram preenchidos com concretos de resistências à compressão de 30, 60, 80 e 100MPa. Os resultados da comparação entre valores de força última experimental e teórica mostraram que as normas avaliadas apresentam bons resultados. A NBR 8800 apresenta resultados conservadores ao passo que o EC4 apresenta, em média, valores de força resistente não conservadores. A correlação tende a piorar para concretos de resistência menor.In this paper results of tests on 32 concrete-filled steel tubular columns under axial load are reported. The test parameters were the concrete compressive strength, the column slenderness (L/D) and the wall thickness (t). The test results were compared with predictions from the codes NBR 8800:2008 and EN 1994-1-1:2004 (EC4). The columns were 3, 5, 7 and 10 length to diameter ratios (L/D) and were tested with 30MPa, 60MPa, 80MPa and 100MPa concrete compressive strengths. The results of ultimate strength predicted by codes showed good agreement with experimental results. The results of NBR 8800 code were the most conservative and the EC4 showed the best results, in mean, but it was not conservative for usual concrete-filled short columns.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) - Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Litterfall, litter stock and water holding capacity in post-mining forest restoration ecosystems, Eastern Amazon

The objective of this study was to evaluate the litterfall deposition, the decomposition rate (KL) and the water holding capacity (WHC) of litter stored in the soil in two areas degraded by mining submitted to different methods of forest restoration: induction of natural regeneration (NR) and planting seedlings of native forest species (PS) with a forest fragment (FF) used as reference. The litterfall deposition was collected monthly over 12 months in collectors of 0.25 m2. The KL was estimated by the relation between annual litter production and litter stock in the soil surface. WHC was determined in the rainy and dry period. The litterfall deposition was lower in PS with values of 6.61 ± 0.20, 10.75 ± 0.52 and 11.83 ± 0.72 Mg ha-1 yr-1 for PS, NR and FF respectively. The KL and WHC were significantly lower in PS when compared to NR and FF, and WHC decreased significantly from the rainy season to the dry season. The induction of natural regeneration was the more effective restoration method for degraded areas regarding litterfall deposition, decomposition and water retention capacity, surpassing planting native tree species and approaching a native forest fragmentinfo:eu-repo/semantics/publishedVersio

Optimization of high pressure processing parameters to enhance the quality attributes of scallops (Nodipecten nodosus)

ABSTRACT: Seafood is one of the most important sources of nutrients. However, they have a short shelf-life and the traditional preservation methods may generate losses in their natural flavour and nutrients. Thisstudy evaluated and optimize the High Pressure Processing (HPP) regarding pressure level (200-400 MPa) and holding time (0-5 min) applied to lion’s paw scallop (Nodipecten nodosus) to reduce microbial contamination while maintaining desirable characteristics. Response surface methodology with a Box-Behnken design and Desirability function were employed to simultaneously optimize these quality attributes. HPP enhanced microbial quality at 200 MPa/5 min, despite promoting inadequate physical-chemical modifications in the adductor muscle of the scallop. In such processing condition, in spite of a slight increase in muscle humidity which could be of benefit, pH increase was also verified, as well as a decrease in water holding capacity (WHC). At more severe level (400 MPa/5 min), a decrease in the shear force related to instrumental texture and in Whiteness (W) and Luminosity (L*) related to color was observed. Simultaneous optimization provided a value of 365MPa / 2min where physicochemical characteristics would be the more similar to the scallop without facing a preservation process

Single channel approach for filtering electroencephalographic signals strongly contaminated with facial electromyography

Eliminating facial electromyographic (EMG) signal from the electroencephalogram (EEG) is crucial for the accuracy of applications such as brain computer interfaces (BCIs) and brain functionality measurement. Facial electromyography typically corrupts the electroencephalogram. Although it is possible to find in the literature a number of multi-channel approaches for filtering corrupted EEG, studies employing single-channel approaches are scarce. In this context, this study proposed a single-channel method for attenuating facial EMG noise from contaminated EEG. The architecture of the method allows for the evaluation and incorporation of multiple decomposition and adaptive filtering techniques. The decomposition method was responsible for generating EEG or EMG reference signals for the adaptive filtering stage. In this study, the decomposition techniques CiSSA, EMD, EEMD, EMD-PCA, SSA, and Wavelet were evaluated. The adaptive filtering methods RLS, Wiener, LMS, and NLMS were investigated. A time and frequency domain set of features were estimated from experimental signals to evaluate the performance of the single channel method. This set of characteristics permitted the characterization of the contamination of distinct facial muscles, namely Masseter, Frontalis, Zygomatic, Orbicularis Oris, and Orbicularis Oculi. Data were collected from ten healthy subjects executing an experimental protocol that introduced the necessary variability to evaluate the filtering performance. The largest level of contamination was produced by the Masseter muscle, as determined by statistical analysis of the set of features and visualization of topological maps. Regarding the decomposition method, the SSA method allowed for the generation of more suitable reference signals, whereas the RLS and NLMS methods were more suitable when the reference signal was derived from the EEG. In addition, the LMS and RLS methods were more appropriate when the reference signal was the EMG. This study has a number of practical implications, including the use of filtering techniques to reduce EEG contamination caused by the activation of facial muscles required by distinct types of studies. All the developed code, including examples, is available to facilitate a more accurate reproduction and improvement of the results of this study

O Programa de Cidades Históricas : por uma política integrada de preservação do patrimônio cultural urbano

O Programa de Cidades Históricas (PCH), implementado a partir de 1973, foi o primeiro programa federal que investiu recursos para a recuperação do patrimônio cultural urbano. Implementado pelo Ministério do Planejamento, buscava o desenvolvimento econômico das cidades históricas e dialogava com outros assuntos em pauta naquele momento, como o desenvolvimento urbano e regional e o turismo cultural. Tinha em sua concepção uma mudança na maneira de abordar as cidades históricas: a partir do entendimento da cidade como produtora de capital, o patrimônio cultural geraria desenvolvimento econômico pelo seu consumo para a atividade turística. De 1973 a 1979, foram investidos 17,3 milhões de dólares, realizando-se 143 obras em monumentos (85% dos investimentos); 8 cursos de qualificação de mão de obra nos três níveis (superior, intermediário e operário); 7 planos urbanísticos; 6 obras em espaços públicos (urbanos); e 10 ações de tipos diversos. Nossa análise busca entender essa política a partir do seu processo de formulação e implementação, no período de 1972 a 1979. Pretende, nesse sentido: a) avaliar as relações de poder em jogo durante a construção e a implementação do programa; b) compreender o grau de sucesso que o programa obteve na construção de um Sistema Nacional de Patrimônio Cultural, analisando sua articulação junto aos estados e outros órgãos federais; e c) avaliar o papel do programa enquanto indutor de novas práticas institucionais no campo da preservação do patrimônio cultural, especialmente com relação ao Iphan e aos estados federativos brasileiros.The Historic Cities Program (PCH: 1973-1979) was the first federal program that has invested resources to the recovery of the urban cultural heritage. Implemented by the Ministry of Planning, sought economic development of historic towns and dialogued with other items on the agenda at the time, such as urban and regional development and cultural tourism. It brought a change in the way of approach the historic towns: from the understanding of the city as a producer of capital, heritage would generate economic development through its consume by the tourism. From 1973 to 1979 it was invested 17.3 million dollars, performing 143 works on monuments (85% of investments); 8 hand-to-work training courses in three levels (top, middle and working class); 7 urban plans; 6 works in public spaces (urban); and 10 shares of various types. Our analysis seeks to understand this policy from its formulation and implementation in the period from 1972 to 1979. The aim, in this sense, is: a) to assess the power relations at play during construction and implementation of the Program; b) to understand the degree of success that the program achieved in building a national system, analyzing its relationship with states and other federal agencies; and c) to evaluate the role of Program while inducing new institutional practices in the field of preservation of cultural heritage, especially with regard to Iphan

Manejo Terapêutico do Paciente Queimado: Revisão de Literatura

Burns are traumatic wounds resulting from thermal, chemical, electrical or radioactive agents that compromise vital skin functions. In Brazil, they constitute one of the main external causes of death, alongside transport accidents and homicides. An integrative review was carried out, using the Google Scholar database with the following descriptors “Burn”, “Pain Management”, “Therapeutic Indication”. In which 8 articles were selected from 1,710, published in English and Portuguese from 2019 to 2024. The main author conducted the analysis, with disagreements resolved between the authors. WHO estimates indicate 300,000 annual deaths from burns globally. In Brazil, one million people suffer burns annually, with young adults being the most vulnerable, mainly in domestic or work environments. The classification of burns, extent of the affected area and treatment are fundamental for the best therapeutic management, given that pain is a prevalent complaint that is difficult to control in these patients. Protocols vary, and wound care, hydration, and pain management are challenges. Different therapies, including agents such as silver sulfadiazine and essential fatty acids, show promising results. Surgical treatment aims to remove compromised tissues, contributing to effective healing. The study reinforces the importance of medical knowledge in the management of burns and its relevance to public health.As queimaduras são feridas traumáticas resultantes de agentes térmicos, químicos, elétricos ou radioativos que comprometem funções vitais tanto da pele, como dos demais órgãos internos. No Brasil, constituem uma das principais causas externas de morte, disputando com acidentes de transporte e homicídios. Realizou-se uma revisão integrativa, utilizando a base de dados Google Acadêmico com os seguintes descritores “Queimadura”, “Manejo da Dor”, “Indicação Terapêutica”. Nos quais foram selecionados 8 artigos entre 1.710, publicados em inglês e português de 2019 a 2024. O autor principal conduziu a análise, com discordâncias resolvidas entre os autores. Estimativas da OMS indicam 300 mil mortes anuais por queimaduras globalmente. No Brasil, um milhão de pessoas anualmente sofrem queimaduras, sendo adultos jovens mais vulneráveis, principalmente em ambientes domésticos ou laborais. A classificação das queimaduras, extensão da área afetada e o tratamento são fundamentais para o melhor manejo terapêutico, haja vista que a dor é uma queixa prevalente e de difícil controle nesses pacientes. Protocolos variam, e o cuidado da ferida, hidratação e manejo da dor são desafios. Diferentes terapias, incluindo agentes como sulfadiazina de prata e ácidos graxos essenciais, apresentam resultados promissores. O tratamento cirúrgico visa a remoção de tecidos comprometidos, contribuindo para a cicatrização eficaz. O estudo reforça a importância do conhecimento médico na abordagem de queimaduras e sua relevância para a saúde pública

Local hydrological conditions influence tree diversity and composition across the Amazon basin

Tree diversity and composition in Amazonia are known to be strongly determined by the water supplied by precipitation. Nevertheless, within the same climatic regime, water availability is modulated by local topography and soil characteristics (hereafter referred to as local hydrological conditions), varying from saturated and poorly drained to well-drained and potentially dry areas. While these conditions may be expected to influence species distribution, the impacts of local hydrological conditions on tree diversity and composition remain poorly understood at the whole Amazon basin scale. Using a dataset of 443 1-ha non-flooded forest plots distributed across the basin, we investigate how local hydrological conditions influence 1) tree alpha diversity, 2) the community-weighted wood density mean (CWM-wd) – a proxy for hydraulic resistance and 3) tree species composition. We find that the effect of local hydrological conditions on tree diversity depends on climate, being more evident in wetter forests, where diversity increases towards locations with well-drained soils. CWM-wd increased towards better drained soils in Southern and Western Amazonia. Tree species composition changed along local soil hydrological gradients in Central-Eastern, Western and Southern Amazonia, and those changes were correlated with changes in the mean wood density of plots. Our results suggest that local hydrological gradients filter species, influencing the diversity and composition of Amazonian forests. Overall, this study shows that the effect of local hydrological conditions is pervasive, extending over wide Amazonian regions, and reinforces the importance of accounting for local topography and hydrology to better understand the likely response and resilience of forests to increased frequency of extreme climate events and rising temperatures

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran\u27s eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R$^{2}$ = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R$^{2}$ = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions

Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types