Prediction of microfibril angle for Eucalyptus microcorys wood by fiber length and basic density

Aim of the study was to estimate the influence of the fiber length and basic density on microfibril angle of Eucalyptus microcorys wood. The study area was in an experimental planting at the Universidade Federal de Lavras, Minas Gerais State, Brazil. Three 37 year-old Eucalyptus microcorys trees were used, from whose stems six centimeter-thick discs were removed, cut at a high of three meters. The disks were sanded and planed to highlight the growth rings. Specimens were taken every 1.5 cm across the radius from pith to bark for determining microfibril angle, fiber length and wood basic density. The microfibril angles were determined by use of polarized light microscopy, while the fiber morphology and basic density were determined by usual methods. The averages found for microfibril angle (12.6°), fiber length (968 µm) and basic density (480 kg.m-3) are, in general, within the range of values reported for these characteristics of wood. The microfibril angle showed accentuated reduction of the average values in the pith-bark direction. The fiber length and basic density showed the opposite behavior. We observed that the density and fiber length may be used as an microfibril angle predictor, accounting for 96% and 79% of its variation, respectively

ESTRUTURA DO LENHO DE Plathymenia reticulata E ALGUMAS IMPLICAÇÕES NA EFICIÊNCIA HIDRÁULICA E RESISTÊNCIA MECÂNICA

  Investigou-se a variação anatômica, velocidade de propagação do som (v), densidade aparente (ρap) e módulo de elasticidade dinâmico (MOEd) na madeira de Plathymenia reticulata. Verificou-se como as variações nessas características podem influenciar na eficiência hidráulica e resistência mecânica. Para a anatomia, empregaram-se as metodologias usuais, a (v) foi medida com equipamento de ultrassom, a (ρap) foi determinada pelo método da balança hidrostática, e a partir dos valores de (v) e (ρap) foi calculado o (MOEd). O diâmetro de vasos aumentou na direção da casca, o que deve acarretar melhor eficiência hidráulica. A frequência de vasos e o MOEd correlacionaram-se negativamente na região da medula, indicando madeira mais flexível e mais resistente à ação dos ventos. Raios mais frequentes diminuem a (v), e como esta também indica a rigidez, regiões com maior frequência de raios apresentam maior flexibilidade. Fibras com paredes mais espessas na base do fuste podem aumentar a resistência das árvores ao receberem uma carga extra. A relação negativa entre ρap e lume das fibras deve-se ao fato de o lume representar espaços vazios que não contribuem na massa. Raios mais largos na direção da casca podem auxiliar no armazenamento de amido, que, quando hidrolisado, também atua na recuperação de vasos embolizados.Palavras-chave: Amarelinho; anatomia da madeira; propriedades da madeira; variação axial; variação radial. AbstractWood structure of Plathymenia reticulata and some implications on hydraulic efficiency and mechanical strength. We investigated the anatomical variation, speed of sound propagation (v), specific gravity (ρap) and dynamic modulus of elasticity (MOEd) in the wood of Plathymenia reticulate Benth. The aim was to determine how variations in these characteristics may influence the hydraulic efficiency and mechanical strength. The anatomical features were analyzed according to usual techniques; (v) was measured with ultrasound equipment, (ρap) was determined with “balança hidrostática” method and from (v) and (ρap) values was calculated (MOEd). The results showed that increase in vessel diameter from pith to bark can result in better hydraulic efficiency. The negative correlation between vessels frequency and MOEd in the pith indicates more flexible wood, contributing to the resistance of young tree to wind action. Rays more frequent decreased (v), as this is also an indication of stiffness; regions with the highest ray frequency provide higher flexibility. Fibers with thicker walls at the base of the stem can increase the tree resistance when they receive an extra load. The negative relationship between ρap and fibers lumen is due increase in empty spaces that no contributed in wood mass. Wider rays in the bark direction can contributed in the storage of starch, which when hydrolyzed can retrieve embolized vessels.Keywords: Amarelinho; wood anatomy; wood properties; axial variation; radial variation.  We investigated the anatomical variation, speed of sound propagation (v), specific gravity (ρap) and dynamic modulus of elasticity (MOEd) in the wood of Plathymenia reticulate Benth. The aim was to determine how variations in these characteristics may influence the hydraulic efficiency and mechanical strength. The anatomical features were analyzed according to usual techniques; (v) was measured with ultrasound equipment, (ρap) was determined with “balança hidrostática” method and from (v) and (ρap) values was calculated (MOEd). The results showed that increase in vessel diameter from pith to bark can result in better hydraulic efficiency. The negative correlation between vessels frequency and MOEd in the pith indicates more flexible wood, contributing to the resistance of young tree to wind action. Rays more frequent decreased (v), as this is also an indication of stiffness; regions with the highest ray frequency provide higher flexibility. Fibers with thicker walls at the base of the stem can increase the tree resistance when they receive an extra load. The negative relationship between ρap and fibers lumen is due increase in empty spaces that no contributed in wood mass. Wider rays in the bark direction can contributed in the storage of starch, which when hydrolyzed can retrieve embolized vessels

Planting density effect on some properties of Schizolobium parahyba wood

This study aims to understand the effect of the initial planting density on the anatomical variability and basic wood density of Schizolobium parahyba var. amazonicum in a planted forest in Amazonia. The effect of the initial planting density on the radial variation from pith to bark of anatomy and basic density was evaluated. There were two planting densities, planting density-I (624 trees ha-1) and planting density-II (312 trees ha-1). Planting density significantly affected only the ray height, fiber length and wall thickness. Radial position was not significant to the height of the rays and the fiber lumen diameter. The interaction planting density × radial position was only significant for the length of the vessel elements, ray frequency and fiber length. The results indicate that the initial planting density influences the radial behavior of certain anatomical characteristics. To obtain gain in terms of total wood per cultivated area, without harm to the density of the produced wood, planting density-I would be most useful, while planting density-II would be suitable for the production of more homogeneous wood, which tends to form adult wood in advance and with some anatomical characteristics appropriate for the plywood industry

Educar para empoderar: o uso de tecnologias educativas para o controle e prevenção de infecção hospitalar / Educating to empower: the use of educational technologies for hospital infection control and prevention

Objetivo: Avaliar a utilização de tecnologias educativas na prevenção e controle de infecções hospitalares em um centro de terapia intensiva (CTI) de um Hospital Público de Ensino de Belém do Pará. Método: estudo de intervenção, realizado com profissionais da saúde do CTI, por meio de atividades de educação em serviço com auxílio de tecnologias educativas, tais como cartilhas e cartazes. Resultados: o uso das tecnologias educativas possibilitou a aprendizagem de novas regras e melhoria no conhecimento pré-existente dos participantes, também garantiu empoderamento nas ações e tomadas de decisões, quanto a prevenção e controle das infecções. Portanto, pode-se sugerir a eficácia da tecnologia educativa ao processo de aprendizagem, visto que, houve um maior segmento de regras previstas nas cartilhas e cartazes educativos e, consequentemente, redução das taxas de infecção no setor investigado. Além disso, os participantes consideraram positivo o uso desse tipo de tecnologia, principalmente, aquelas relacionadas à higienização das mãos. Conclusão: As tecnologias educativas utilizadas apresentaram um resultado eficaz no processo de aprendizagem dos profissionais de saúde, relacionando-se com a futura redução das taxas de controle de infecções do hospital estudado. Contudo, futuras investigações podem verificar o efeito temporal dessas medidas, além de testarem novas tecnologias educacionais

HIGIENIZAÇÃO E MANUTENÇÃO DAS PRÓTESES FIXAS - UMA REVISÃO DA LITERATURA

The success of fixed partial dentures is subject to mechanical and biological factors. The primary reasons for the loss of this type of prosthesis are dental caries infiltration and periodontal problems resulting from poor hygiene. Hygiene techniques should be informed, trained, and motivated by the dentist. It will define the longevity of the prosthesis. Objectives: The aim of this study is to highlight all the techniques used to sanitize fixed prostheses, showing their biological and mechanical failures if they are not sanitized. The indications and contraindications, advantages and disadvantages of fixed prostheses were also presented. Method: A literature review was conducted by searching the SciELO, PubMed, and LILACS databases with the keywords "Fixed Partial Denture; Oral hygiene; Dental prosthesis" for the period from 2005 to 2023. Twenty relevant articles in Portuguese, Spanish, and English were selected. In addition to articles, academic books available in the UNIBRA Professor Aluísio Viana Library collection were used. Much information was obtained during the research through surveys on Instagram's "story" feature, which was answered by an audience of 200 people with estimated age ranges from 15 to 60 years. Results: Studies suggest that biological and mechanical factors, whether individually or in combination, directly influence the longevity and success rate of dental prosthetics. The efficiency and frequency of oral hygiene practices also serve as influential factors. Neglect or absence of proper oral care can result in consequences such as cavities, periodontal disease, endodontic complications, and/or mechanical failures like retention loss, cracks, subsequent fractures, loss of coating material, fracture of the metal framework, abutment tooth issues, and marginal defects. Final considerations: It can be concluded that the main factor for the success and longevity of fixed prostheses is hygiene, as its deficiency will lead to the emergence of diseases and injuries related to fixed prostheses, resulting in the failure of prosthetic rehabilitative treatment. O sucesso das próteses parciais fixas está relacionado a fatores mecânicos e biológicos. As principais razões para a perda desse tipo de prótese é a infiltração por cárie dental e problemas periodontais, decorrentes da higienização deficiente.  As técnicas de higiene devem ser informadas, treinadas e motivadas pelo cirurgião dentista. A mesma vai definir a longevidade da prótese. Objetivos: O presente trabalho tem como objetivos evidenciar todas as técnicas de higienização das próteses fixas, mostrando suas falhas biológicas e mecânicas caso ocorra a ausência da higienização. Também foi exposto as indicações e contra-indicação, vantagem e desvantagens da prótese fixa. Método:  Foi realizada uma revisão de literatura mediante o levantamento nas bases de dados SciELO, PubMed e LILACS com as palavras-chaves “Prótese Parcial Fixa; Higiene bucal; Prótese dentária;’’ referente ao período de 2005 a 2023, sendo selecionados 20 artigos em português, espanhol e inglês relevantes sobre higienização das próteses fixas. Resultados: Os estudos levam ao entendimento que os fatores biológicos e mecânicos sejam eles de forma individual ou associados influenciam diretamente na longevidade e taxa de sucesso da prótese. Tendo a eficiência e a frequência da higienização bucal, também como ponto de influência. A negligência ou a ausência dela gera consequências como cáries, doença periodontal, complicações endodônticas e/ou falhas mecânicas, como perda de retenção, trincas e subsequente fraturas, perda do material de revestimento, fratura da estrutura metálica, dente pilar e defeitos marginais. Considerações finais: Pode-se concluir que o principal fator para obtenção de sucesso e longevidade da prótese fixa é a higienização, pois a deficiência desta vai desencadear o surgimento de doenças e lesões relacionadas a prótese fixa, resultando no insucesso do tratamento reabilitador protético. &nbsp

Caracterização de equinos competidores de Pega de Boi no Mato

Objetivou-se com o trabalho caracterizar os equinos participantes de Pegas de Boi no Mato e verificar se esses animais permanecem com as características físicas do remanescente cavalo Nordestino, raça pioneira na lida com o gado no Sertão, ou se estão aproximando das dimensões corporais dos cavalos Quarto de Milha, raça exótica em ascensão no Nordeste brasileiro devido às Vaquejadas. Para tanto, foram utilizados 102 equinos participantes de Pegas de Boi no Mato. A primeira etapa do estudo consistiu em uma entrevista aos proprietários dos cavalos, com aplicação de questionário predefinido, para obter informações sobre os animais. Na segunda etapa foram obtidas 15 medidas lineares dos equinos e com elas calculados sete índices morfométricos. As medidas foram utilizadas para comparar dois grupos raciais, mestiços e animais sem raça definida, através do delineamento experimental inteiramente ao acaso composto pelos dois tratamentos (grupos raciais). Observou-se nas Pegas de Boi no Mato, predomínio de equinos machos castrados, na faixa etária entre 5 e 10 anos, de pelagens alazã, tordilha e castanha, cujas funções vão além das participações nas disputas. Os equinos mestiços apresentaram valores superiores aos animais sem raça definida em nove das 15 medidas lineares. Além disso, houve diferença entre os grupos raciais em cinco dos sete índices morfométricos. Concluiu-se que tanto os mestiços quanto os equinos sem raça definida participantes das Pegas de Boi no Mato possuem medidas e proporções corporais intermediárias entre o remanescente cavalo Nordestino e equinos Quarto de Milha de Vaquejada

Wild dogs at stake: deforestation threatens the only Amazon endemic canid, the short-eared dog (Atelocynus microtis)

The persistent high deforestation rate and fragmentation of the Amazon forests are the main threats to their biodiversity. To anticipate and mitigate these threats, it is important to understand and predict how species respond to the rapidly changing landscape. The short-eared dog Atelocynus microtis is the only Amazon-endemic canid and one of the most understudied wild dogs worldwide. We investigated short-eared dog habitat associations on two spatial scales. First, we used the largest record database ever compiled for short-eared dogs in combination with species distribution models to map species habitat suitability, estimate its distribution range and predict shifts in species distribution in response to predicted deforestation across the entire Amazon (regional scale). Second, we used systematic camera trap surveys and occupancy models to investigate how forest cover and forest fragmentation affect the space use of this species in the Southern Brazilian Amazon (local scale). Species distribution models suggested that the short-eared dog potentially occurs over an extensive and continuous area, through most of the Amazon region south of the Amazon River. However, approximately 30% of the short-eared dog's current distribution is expected to be lost or suffer sharp declines in habitat suitability by 2027 (within three generations) due to forest loss. This proportion might reach 40% of the species distribution in unprotected areas and exceed 60% in some interfluves (i.e. portions of land separated by large rivers) of the Amazon basin. Our local-scale analysis indicated that the presence of forest positively affected short-eared dog space use, while the density of forest edges had a negative effect. Beyond shedding light on the ecology of the short-eared dog and refining its distribution range, our results stress that forest loss poses a serious threat to the conservation of the species in a short time frame. Hence, we propose a re-assessment of the short-eared dog's current IUCN Red List status (Near Threatened) based on findings presented here. Our study exemplifies how data can be integrated across sources and modelling procedures to improve our knowledge of relatively understudied species

Acesso e uso de serviços odontológicos por indígenas do Brasil / Access and use of dental services by indigenous people in Brazil

Devido inúmeras dificuldades de acessos sendo explanados como limitadores da atenção à saúde remetida aos povos indígenas em diferentes regiões do Brasil, os principais entraves estão entre as dificuldades organizacionais, geográficos e culturais, incluindo a deficiência em relação à escassez ou primordialmente de interpretes culturais que possibilitem a comunicação das etnias com os serviços de saúde. Objetivo deste estudo foi descrever o acesso e o uso dos serviços odontológicos por populações indígenas no Brasil. Realizou-se uma revisão integrativa no qual foram selecionados artigos publicados entre 2003 e 2019. As políticas públicas que direcionam as atividades são a PNAB, a Política Nacional de Saúde Bucal. São mencionados ainda as diretrizes e os princípios do SUS. Foi Avaliado a relação ao incremento da cárie, necessidade de tratamento de cárie dentária e analisar o transporte e viabilização de veículos como meio de locomoção para chegar em áreas de prestação dos serviços odontológicos. Conclui-se há necessidade de formulação de estratégias de políticas públicas juntamente com governantes e líderes a frente do poder para melhoria dos serviços e acessos para saúde dos povos indígenas tendo em vista a falta de acesso a assistência básica regular e a métodos preventivos. 

Temporal patterns of cytokine and injury biomarkers in hospitalized COVID-19 patients treated with methylprednisolone

BackgroundThe novel coronavirus disease 2019 (COVID-19) presents with complex pathophysiological effects in various organ systems. Following the COVID-19, there are shifts in biomarker and cytokine equilibrium associated with altered physiological processes arising from viral damage or aggressive immunological response. We hypothesized that high daily dose methylprednisolone improved the injury biomarkers and serum cytokine profiles in COVID-19 patients.MethodsInjury biomarker and cytokine analysis was performed on 50 SARS-Cov-2 negative controls and 101 hospitalized severe COVID-19 patients: 49 methylprednisolone-treated (MP group) and 52 placebo-treated serum samples. Samples from the treated groups collected on days D1 (pre-treatment) all the groups, D7 (2 days after ending therapy) and D14 were analyzed. Luminex assay quantified the biomarkers HMGB1, FABP3, myoglobin, troponin I and NTproBNP. Immune mediators (CXCL8, CCL2, CXCL9, CXCL10, TNF, IFN-γ, IL-17A, IL-12p70, IL-10, IL-6, IL-4, IL-2, and IL-1β) were quantified using cytometric bead array.ResultsAt pretreatment, the two treatment groups were comparable demographically. At pre-treatment (D1), injury biomarkers (HMGB1, TnI, myoglobin and FABP3) were distinctly elevated. At D7, HMGB1 was significantly higher in the MP group (p=0.0448) compared to the placebo group, while HMGB1 in the placebo group diminished significantly by D14 (p=0.0115). Compared to healthy control samples, several immune mediators (IL-17A, IL-6, IL-10, MIG, MCP-1, and IP-10) were considerably elevated at baseline (all p≤0.05). At D7, MIG and IP-10 of the MP-group were significantly lower than in the placebo-group (p=0.0431, p=0.0069, respectively). Longitudinally, IL-2 (MP-group) and IL-17A (placebo-group) had increased significantly by D14. In placebo group, IL-2 and IL-17A continuously increased, as IL-12p70, IL-10 and IP-10 steadily decreased during follow-up. The MP treated group had IL-2, IFN-γ, IL-17A and IL-12p70 progressively increase while IL-1β and IL-10 gradually decreased towards D14. Moderate to strong positive correlations between chemokines and cytokines were observed on D7 and D14.ConclusionThese findings suggest MP treatment could ameliorate levels of myoglobin and FABP3, but appeared to have no impact on HMGB1, TnI and NTproBNP. In addition, methylprednisolone relieves the COVID-19 induced inflammatory response by diminishing MIG and IP-10 levels. Overall, corticosteroid (methylprednisolone) use in COVID-19 management influences the immunological molecule and injury biomarker profile in COVID-19 patients

Secreted Human Amyloid Precursor Protein Binds Semaphorin 3a and Prevents Semaphorin-Induced Growth Cone Collapse

The amyloid precursor protein (APP) is well known for giving rise to the amyloid-β peptide and for its role in Alzheimer's disease. Much less is known, however, on the physiological roles of APP in the development and plasticity of the central nervous system. We have used phage display of a peptide library to identify high-affinity ligands of purified recombinant human sAPPα695 (the soluble, secreted ectodomain from the main neuronal APP isoform). Two peptides thus selected exhibited significant homologies with the conserved extracellular domain of several members of the semaphorin (Sema) family of axon guidance proteins. We show that sAPPα695 binds both purified recombinant Sema3A and Sema3A secreted by transfected HEK293 cells. Interestingly, sAPPα695 inhibited the collapse of embryonic chicken (Gallus gallus domesticus) dorsal root ganglia growth cones promoted by Sema3A (Kd≤8·10−9 M). Two Sema3A-derived peptides homologous to the peptides isolated by phage display blocked sAPPα binding and its inhibitory action on Sema3A function. These two peptides are comprised within a domain previously shown to be involved in binding of Sema3A to its cellular receptor, suggesting a competitive mechanism by which sAPPα modulates the biological action of semaphorins