Resumen Contexto: La construcción en madera no está entre las opciones más populares debido a problemas culturales en Brasil. Los estándares y costos de la habitación en madera siguen siendo temas inciertos, y este estudio busca investigar estas brechas seculares. Método: Los costos unitarios básicos para diferentes estándares de acabado y tipos de producción se midieron a través de entrevistas cara a cara dirigidas por un cuestionario semiestructurado. Se utilizó un margen de error para validar todos los resultados. Se entrevistó aleatoriamente a empresarios de seis estados brasileños para obtener una muestra representativa. Resultados: El muestreo superó el 50% de la población del sector y proporcionó resultados significativos. Más del 40% de las técnicas de construcción en madera mostraron costos competitivos en comparación con la albañilería. Existen alternativas viables de vivienda en madera en los diferentes escenarios analizados. Conclusiones: Las casas de madera son económicamente viables en Brasil, incluso en comparación con los ejemplos tradicionales construidos en albañilería. Los costos atractivos para todas las clases sociales simbolizan un factor fuerte en la conquista de los mercados inmobiliarios.

Abstract Context: Timber construction is not among the most popular options due to cultural issues in Brazil. Timber housing standards and costs remain uncertain subjects, and this study seeks to investigate these secular gaps. Method: Basic unitary costs for different finishing standards and production types were measured through face-to-face interviews led by a semi-structured questionnaire. A margin of error was used to validate all results. Entrepreneurs from six Brazilian states were randomly interviewed to obtain a representative sample. Results: The sampling exceeded 50% of the sector population and provided significant outcomes. More than 40% of timber housing techniques showed competitive costs in comparison with masonry. There are feasible alternatives of timber housing for the different scenarios analyzed. Conclusions: Timber houses are economically viable in Brazil, even compared to traditional examples built via masonry. Attractive costs for all social classes symbolize a strong factor in conquering housing markets.

Abstract: Our goal was to determine physical properties and anatomical features in 33-year-old Hevea brasiliensis clones. We cut wood samples from clones LCB510, RRIM600, IAN873, IAN717 and GT1 planted in Selvíria, Mato Grosso do Sul, Brazil. We used standard techniques in wood studies. We found that clones differ in basic density, volumetric shrinkage and anatomical features, with the exception of ray width. Basic density, volumetric shrinkage, fiber length, fiber wall thickness, vessel element length and vessel diameter tended to increase from pith to bark, while vessel frequency propended to decrease. We conclude that wood of the studied clones has potential for industrial use.

Abstract This study aimed to analyze the properties of 38-year-old Cariniana legalis wood from trees planted with three spacings between trees: 3 × 2.5, 3 × 2, and 3 × 1.5 m. Five trees were collected from each tree spacing. Discs were collected from the trunk base of each tree and at 2.5 and 5.0 m. The vessel diameter was significantly wider for a spacing of 3 x 2.5 m compared to that of 3 x 1.5 m. Basic density, apparent density, volumetric shrinkage, and natural moisture content were influenced by longitudinal position. However, fiber length and fiber wall thickness showed no significant differences. Basic density and natural moisture content were inversely proportional. Our study shows that the anatomical features of C. legalis wood were more sensitive to variations in tree spacing than its physical properties.

Resumen El objetivo de este estudio fue analizar las propiedades de la madera árboles de Cariniana legalis de 38 años plantados con tres espaciamientos: 3 × 2.5, 3 × 2 y 3 × 1.5 m. Se cortaron cinco árboles por cada espaciamiento. Se recolectaron discos de la base del tronco de cada árbol y a 2.5 y 5.0 m. El diámetro de los vasos fue significativamente más ancho en el espaciamiento de 3 x 2.5 m en contraste con el de 3 x 1.5 m. La densidad básica, la densidad aparente, la contracción volumétrica y el contenido de humedad natural fueron influenciados por la posición longitudinal. Sin embargo, la longitud de la fibra y el grosor de la pared de la fibra no presentaron diferencias significativas. La densidad básica y el contenido de humedad natural fueron inversamente proporcionales. Nuestro estudio muestra que las características anatómicas de la madera de C. legalis fueron más sensibles a la variación del espaciamiento entre árboles que sus propiedades físicas.

RESUMO Para identificar o tempo gasto com as diferentes técnicas de construção de casas de madeira, este estudo avalia o tempo de execução de diferentes modelos disponíveis no Brasil. Utilizando entrevistas face-a-face, formulários semiestruturados foram randomicamente aplicados para coletar o tempo médio de acordo com distintos métodos de produção. As técnicas mais eficientes foram: ‘tábua e mata-junta’, ‘pilar-viga’ e ‘casa de toras ’ utilizando produção artesanal; ‘tábua e mata-junta’, ‘paliteiro com alvenaria’ e ‘pilar-viga’ em processo semi-industrial; e, ‘modular para canteiros de obras ’, ‘modular em madeira laminada colada-cruzada’ e ‘entramado leve modular’ em produção industrial. Diferentes produtores industriais não foram tão ágeis como seus concorrentes artesanais devido aos obstáculos produtivos em projetos customizados. A construção em madeira oferece um tempo produtivo mais baixo que a alvenaria, representando uma forma ágil para construir uma moradia sustentável e versátil.

ABSTRACT To identify the time spent with the different construction techniques of timber houses, this study evaluates the execution time of different models available in Brazil. Using face-to-face interviews, semi-structured questionnaires were randomly applied to collect average time according to distinct production methods. The most efficient techniques were: ‘clapboard and wainscot’, ‘post-and-beam’, and ‘log-home’ using artisanal production; ‘clapboard and wainscot’, ‘stick framing with masonry’, and ‘post-and-beam’ in semi-industrial process; and, ‘modular for building sites’, ‘modular in cross-laminated timber’ and ‘modular woodframe’ in industrial production. Different industrial developers were not as agile as artisanal competitors due to production obstacles in customized projects. Timber construction offers lower execution time than masonry, representing an agile form to build a versatile sustainable dwelling.

RESUMO A adaptação edafoclimática das variedades e/ou clones de cana-de-açúcar pode garantir maior produtividade de forragem para a alimentação animal. Para tanto, foi elaborado um experimento no campus de Seropédica da Universidade Federal Rural do Rio de Janeiro, para avaliação de duas variedades (RB867515 e RB969017) e dois clones (RB058046 e RB098022) de cana-de-açúcar, sob um delineamento de blocos casualizados, com sete repetições. Foram avaliadas variáveis biométricas, perfilhos m-1, índice de área foliar (IAF), Grau Brix e índice de maturação (IM), além das produtividades de forragem e total durante o cultivo do ciclo de cana-planta. O plantio foi realizado em 08/10/2018 e a colheita em 13/09/2019, aos 323 dias após plantio (DAP). Os dados foram analisados pelo software R, sob blocos ao acaso, e medidas repetidas no tempo para as variáveis biométricas, perfilhos m-1, IAF, Grau Brix e IM. As médias foram comparadas pelo teste Tukey (p < 0,10). O clone RB098022 apresentou 20,2% mais perfilhos m-1 que ambas as variedades. Aos 296 DAP ambos os clones e a variedade RB969017 apresentaram IM maiores que 0,85, caracterizando-os como de ciclo mais precoce do que a variedade RB867515 (IM = 0,91 aos 323 DAP). Maiores produtividades e semelhantes de forragem e total foram verificadas para o clone RB098022 e a variedade RB867515 (médias de 141,6 e 151,2 Mg ha-1, respectivamente). Todos os materiais genéticos se adaptaram às condições edafoclimáticas durante o cultivo decana-planta, sendo recomendado a utilização do clone RB098022 e da variedade RB867515 para a alimentação animal na região da Baixada Fluminense. Todos os materiais genéticos se adaptaram às condições edafoclimáticas durante o cultivo decana-planta, sendo recomendado a utilização do clone RB098022 e da variedade RB867515 para a alimentação animal na região da Baixada Fluminense.

ABSTRACT The edaphoclimatic adaptation of sugarcane varieties and clones can ensure higher forage productivity for animal feed. An experiment was conducted at the Seropédica campus of the Federal Rural University of Rio de Janeiro for the evaluation of two varieties (RB867515 and RB969017) and two clones (RB058046 and RB098022) of sugarcane under a randomized block design with seven replications. Biometric variables, tillers m-1, leaf area index (LAI), Brix degree, maturation index (MI), as well as forage and total yields, were evaluated during the cultivation of the sugarcane-plant cycle. Sugarcanes were planted on 10/08/2018 and harvested on 09/13/2019, totaling 323 days after planting (DAP). The data were analyzed using the R software, under randomized blocks and repeated measurements in time for biometric variables, tillers m-1, LAI, Brix Degree and MI. Means were compared using the Tukey test (p < 0.10). Clone RB098022 presented 20.2% more tillers m-1 than both the other varieties. At 296 DAP, both clones and the variety RB969017 presented MI higher than 0.85, indicating them as an earlier cycle than the variety RB867515 (MI = 0.91 to 323 DAP). Higher and similar forage and total yields were obtained with clone RB098022 and variety RB867515 (means 141.6 and 151.2 Mg ha-1, respectively). All sugarcanes adapted to edaphoclimatic conditions during plant cane cultivation, and it is recommended to use the clone RB098022 and the variety RB867515 for animal feed in the Baixada Fluminense region.

ABSTRACT: Eucalypts are the most planted hardwood in the world, with 30 million ha. under cultivation. There are approximately 700 species of eucalypts, but more than 90 % of the plantations are concentrated in nine species of the Subgenus Symphyomyrtus in the Sections Exsertaria, Latoangulatae and Maidenaria. Since 2000, with the advancement of biotechnology, many species have been reclassified and regrouped according to their morphological and physiological characteristics, DNA structure and geographic distribution. This work had as its objective the formulation of a critical analysis which presents the main characteristics that will identify the species of Eucalyptus of these new sections. The species are classified mainly according to geographic distribution, where crosses occur; as evolution in the subgenus Symphyomyrtus is preferably reticulated (with backcrosses), which makes it difficult to identify the rate by molecular and morphological markers. Environmental ecological similarity will define whether the hybrid will become a new species or regress to one parent and become an ecotype. The hybrid will become a new species when it has ecological characteristics different from its parents.

RESUMO Esse estudo objetivou avaliar sazonalmente a histomorfometria do epidídimo de Dermanura cinerea (Gervais, 1856) em um fragmento de Mata Atlântica no nordeste do Brasil. Foram utilizados 18 espécimes machos adultos capturados por redes de neblina. As coletas ocorreram mensalmente ao longo de dezoito meses, durante duas noites consecutivas e os dados meteorológicos foram fornecidos pelo Instituto Nacional de Meteorologia. Depois de eutanasiados, os espécimes tiveram os epidídimos coletados e esses órgãos foram fixados e processados. As lâminas histológicas foram coradas por Hematoxilina - Eosina e analisadas em microscopia óptica. Os parâmetros morfométricos analisados foram as áreas do túbulo, do lúmen e do epitélio das regiões do segmento inicial, cabeça, corpo e cauda do epidídimo. Os dados histomorfométricos obtidos foram submetidos às análises no teste U de Mann-Whitney. Os resultados revelaram que D. cinerea apresentou espermatozoides em todas as regiões do epidídimo, exceto no segmento inicial. As maiores médias das áreas tubular, do lúmen e do epitélio nas quatro regiões, foram constatadas durante os meses secos. Portanto, D cinerea apresentou maior sensibilidade na região da cauda do epidídimo, ao longo dos meses com baixos índices pluviométricos. Isso indica que as condições ambientais apresentam considerável influência sobre a morfofisiologia epidídimária dessa espécie, sobretudo, em relação ao armazenamento de espermatozoides na cauda desse órgão, em área de Mata atlântica do nordeste brasileiro.

ABSTRACT Description and seasonal variation in epididymal histomorphometry of Dermanuracinerea (Chiroptera: Phyllostomidae) in a fragment of the Atlantic Forest in the Northeastern Brazil. This study aimed to evaluate seasonal patterns in the histomorphometry of the epididymis of Dermanura cinerea (Gervais, 1856) in a fragment of the Atlantic Forest in the Northeastern Brazil. Eighteen adult male specimens captured by mist net were used. The field-work occurred monthly over 18 months, during two consecutive nights. Meteorological data (precipitation) were obtained from the National Institute of Meteorology. After euthanasia, specimens had the epididymis collected, which were fixed and processed. The histological slides produced were stained by Hematoxylin - Eosin and analyzed by optical microscopy. The morphometric parameters analyzed were the tubular, lumen and epithelium areas, of the regions of the initial segment, caput, corpus and cauda of the epididymis. The histomorphometric data were submitted to the Mann-Whitney U test analyzes. The results showed that D. cinerea presented spermatozoa in all regions of the epididymis, except in the initial segment. The highest averages of the tubular, lumen and epithelial areas in the four regions were observed during the dry months. Therefore, D cinerea presented greater sensibility in the region of the cauda of the epididymis, during the months with low rainfall indices. This indicates that environmental conditions have considerable influence on the epididymal morphophysiology of this species, especially in relation to the storage of sperm in the tail of this organ, in area of Atlantic forest in northeastern Brazil.

Abstract Euterpe precatoria (Açaí-do-Amazonas) produces fruits of which the fresh pulp is consumed. It is almost exclusively collected by extractivist farmers, because no selected genotypes are available for the establishment of plantations. For the domestication and breeding of the species, mating system studies are needed for strategy formulation. This study evaluated the mating system of a natural population of E. precatoria. Thirteen progenies were genotyped with 13 microsatellite loci by capillary electrophoresis in an automated DNA sequencer. Estimates of single-locus and multilocus outcrossing rates were 1.0, and paternity correlation was low ( r ^ p ( m )>= 0.293). Euterpe precatoria families consist mainly of half-sibs and the reproductive strategy of the species is allogamy.

Abstract Bamboo canes are a unique construction raw material for several types of structures, and there is a growing acceptance of bamboos for structural uses. However, they have as a disadvantage their propensity to attack by insects. In this work, a study of the effectiveness of three different types of preservatives was made with: 1) traditional chemicals, 2) natural substances with low risk to humans and 3) thermal at different temperatures to prevent the Dinoderus minutus beetle attack to Bambusa vulgaris vittata bamboo species. The first two treatments were performed by immersion, and thermal type was made by a drying process. Every two weeks, the attack on three specimens of each treatment was evaluated, including those corresponding to a control specimen without any preservation element. The results showed that most of the treatments by immersion were effective, reducing considerably the attack of the insects in comparison with the control. As for the heat treatment, temperatures less than or equal to 130 °C did not prove to be effective; temperatures of 190 °C and 210 °C revealed acceptable efficiencies.

Resumen Las cañas de bambú son un material de construcción único para diversos tipos de estructuras y cada vez hay una mayor aceptación de los bambúes para usos estructurales. Sin embargo, tienen como inconveniente su propensión al ataque por insectos. En este trabajo se hizo un estudio de la eficacia de tres diferentes tipos de preservadores: 1) químicos tradicionales, 2) naturales de bajo riesgo para el ser humano y 3) térmicos a diferentes temperaturas, para prevenir el ataque del insecto escarabajo Dinoderus minutus al bambú de la especie Bambusa vulgaris vittata. Los dos primeros tratamientos se realizaron por inmersión y el tipo térmico fue hecho por el proceso de secado. Cada dos semanas, se evaluó el ataque a tres especímenes de cada tratamiento, incluyendo los correspondientes a un testigo sin elemento preservador alguno. Los resultados mostraron que la mayoría de los tratamientos por inmersión fueron eficaces, reduciendo considerablemente el ataque de los insectos en comparación con el testigo. En cuanto al tratamiento térmico, las temperaturas menores o iguales a 130 °C no mostraron ser eficaces; las temperaturas de 190 °C y 210 °C revelaron eficacias aceptables.

RESUMO: Esse estudo objetivou analisar o estágio reprodutivo, histologia e morfometria do ovário de Dermanura cinerea em um fragmento de Mata Atlântica da Reserva Biológica de Saltinho (Pernambuco, Brasil). Foram utilizadas fêmeas adultas capturadas por redes de neblina, de modo que as coletas ocorreram mensalmente, durante duas noites consecutivas de Junho/2014 a Novembro/2015. Os dados meteorológicos foram fornecidos pelo Instituto Nacional de Meteorologia e agrupados, juntamente com os dados reprodutivos, em seis períodos, sendo estes: período I (Junho a agosto/2014), período II (Setembro a novembro/2014), período III (Dezembro/2014 a fevereiro/2015) período IV (Março a maio/2015), período V (Junho a agosto/2015) e período VI (Setembro a novembro/2015). As fêmeas foram classificadas, de acordo com o estágio reprodutivo em: inativas, grávidas, lactantes e pós-lactantes. Das 25 fêmeas capturadas, foram selecionadas, para as análises histomorfométricas dos ovários, 10 fêmeas inativas, as quais foram eutanasiadas. Depois disso, os espécimes tiveram os seus ovários removidos, fixados, processados e inclusos em paraplast. Os cortes foram corados por Hematoxilina - Eosina e as lâminas histológicas produzidas foram submetidas às devidas análises em microscópio óptico. Cada tipo de folículo ovariano foi estimado de acordo com as características histológicas evidenciadas para outros mamíferos. Nas análises morfométricas, considerou-se: a área do ovário (mensurada em milímetro quadrado), quantificação dos diferentes tipos de folículos ovarianos (primários unilaminar e multilaminar, antrais e maduros) e corpo lúteo, bem como foi medida a área de cada um desses diferentes tipos de folículos (mensurada em micrômetro quadrado). Os resultados indicaram a presença de 16 fêmeas inativas, 5 lactantes, 4 grávidas e nenhuma pós-lactante. As análises histológicas destacaram que os ovários de D. cinerea possui características, estruturas e tipos celulares padrões semelhantes ao dos demais mamíferos. Os dados morfométricos da área do ovário foram avaliados estatisticamente por meio do teste t de Student. Assim, as análises histomorfométricas ovariana são de suma importância para inferir com maior segurança sobre a reprodução de uma dada espécie. Portanto, ficou constatado que as fêmeas de D. cinerea apresentam dois picos reprodutivos, isto é, podem parir no final de períodos secos ou do início para metade do período chuvoso. A principal característica observada no ovário dessa espécie, encontrada em área de Mata Atlântica do estado de Pernambuco, foi a preparação do córtex ovariano para ovular em meses de elevados índices pluviométricos ao longo do ano. Logo, essa espécie procura ajustar seu período reprodutivo com as variações das condições ambientais, de forma que a reprodução ocorra em períodos mais favoráveis para manutenção da prole.

ABSTRACT: This study aimed to analyze the reproductive stage, histology and morphometry of the ovary of Dermanura cinerea in an Atlantic Forest fragments in the Biological Reserve of Saltinho, Pernambuco, Brazil. Adult females were captured monthly by mist net, during two consecutive nights from June/2014 to November/2015. The meteorological data were provided by the National Institute of Meteorology and grouped together with the reproductive data, in six periods: period I (June to August/2014), period II (September to November/2014), period III (December/2014 to February/2015), period IV (March to May/2015), period V (June to August/2015) and period VI (September to November/2015). The females were classified according to their reproductive stages in: Inactive, pregnant, lactating and postlactating. Among the 25 females caught, 10 inactive females were selected for the histomorphometric analysis of the ovaries and then they were euthanized. After that, the specimens had their ovaries removed, fixed, processed and included in Paraplast. The organs were cut and stained by Hematoxylin - Eosin and the histological slides produced were submitted to the appropriate optical microscope analysis. Each type of ovarian follicle was estimated according to the histological characteristics evidenced for other mammals. In the morphometric analysis, it was considered: The area of the ovary (measured in square millimeter), Quantification of different types of ovarian follicles (unilaminar and multilaminar primary follicles, antral and matures) and corpus luteum, as well as the area of each by those different follicles (measured in square micrometer) The results indicated that 16 females were inactive, 5 were lactating, 4 were pregnant and no post-lactating. The histological analysis revealed that the ovaries of D. cinerea exhibit characteristics, structures and cellular types similar to other mammals. The morphometric data of the study area were statistically evaluated using the Student’s t-test. Therefore, ovarian histomorphometric analysis are very important to infer with greater certainty about the reproduction of a species. Thus, it was observed that females of D. cinerea exhibit two reproductive peaks, that is, they can give birth either at the end of dry periods or from the beginning to the middle of the rainy season. The main feature observed in the ovary of this species, found in the Atlantic Forest area of the state of Pernambuco, is the preparation of the ovarian cortex to ovulate in months of high rainfall throughout the year. Therefore, this species tries to adjust its reproductive period with the variations of the environmental conditions, so that the reproduction might occur during the period more favorable for the maintenance of their offspring.

ABSTRACT In Brazil, Hevea brasiliensis plantations are principally destined for latex production. In the national literature however, there are few studies on the mechanical properties of rubberwood. This study aimed to evaluate the potential of rubberwood in the manufacture of glulam beams (VLC), through the use of pieces of sawn wood of H. brasiliensis clone RRIM 600 glued using mono-component polyurethane adhesive. The beams were subjected to destructive bending tests according to the procedures of standard NBR 7190/97. The results were correlated with the resistance to shearing in the solid wood and the glue line. The structural performance of VLCs manufactured from rubberwood was significant when the last layer was removed from the bending calculation. This layer presented problems in the finger joint. The bending strength of VLCs is highly dependent on the tensile strength of the finger joint, which proved to be the critical point in this study.

RESUMO Esse estudo analisou o estágio reprodutivo, a histologia e a morfometria dos testículos de Dermanura cinerea (Gervais, 1856) em fragmento de Mata Atlântica no Litoral Sul de Pernambuco. Os espécimes foram capturados por redes de neblina e as coletas ocorreram mensalmente, ao longo de duas noites consecutivas, durante 18 meses. Os dados meteorológicos foram agrupados em meses chuvosos e secos. Foram utilizados 18 espécimes adultos, os quais foram classificados em machos com testículos descendentes e não descendentes. Para as análises histológicas, os testículos foram coletados, fixados e processados seguindo a técnica histológica de rotina. As lâminas obtidas foram coradas por Hematoxilina-Eosina. Nas análises morfométricas foram mensuradas a área de ocupação do compartimento tubular e intertubular, quantificados o número de células de Leydig, de Sertoli, de espermatócitos e de espermátides alongadas. Os dados morfométricos foram submetidos às análises estatísticas. Dermanura cinerea apresentou maior atividade de produção espermática em meses secos e maior produção hormonal em meses chuvosos. Essas informações estão relacionadas também com o padrão reprodutivo das fêmeas e com a elevação nos índices pluviométricos, já que é um fator determinante na mediação da disponibilidade alimentar das espécies frugívoras, como D. cinerea em área de Mata Atlântica de Pernambuco.

ABSTRACT This study analyzed the reproductive stage, histology and morphometry of the testes of Dermanura cinerea (Gervais, 1856) in Atlantic Forest fragment on the South Coast of Pernambuco. Specimens were captured by mist net, and collections occurred monthly over two consecutive nights for 18 months. The meteorological data were grouped in rainy and dry months. Eighteen adult specimens were used, which were classified in males with descendant testes and with testes no descendant. For the histological analysis, the testes were collected, fixed and processed following the routine histological technique. The slides obtained were stained by Hematoxylin-Eosin. In the morphometric analysis the area of occupation of the tubular and intertubular compartment were measured, the number of Leydig, Sertoli, spermatocytes and elongated spermatids were quantified. The morphometric data were submitted to statistical analysis. Dermanura cinerea presented higher sperm production activity in dry months and higher hormone production in rainy months. This information is also related to the reproductive pattern of the females and to the increase in rainfall indexes, since it is a determinant factor in the mediation of the food availability of the frugivorous species, such as D. cinerea in the Atlantic Forest area of Pernambuco.

Resumo Foram estudadas as relações entre anatomia da madeira, condutividade hidráulica, densidade aparente e cisalhamento paralelo à grã no tronco de árvores de Handroanthus vellosoi objetivando-se identificar os possíveis trade-offs entre a condutividade hidráulica e propriedades mecânicas. Para este estudo foram cortadas 12 árvores com 24 anos de idade, discos com 10 cm de espessura foram retirados em três alturas: base do tronco, um e dois metros de altura. Propomos que a relação entre a condutividade hidráulica e resistência mecânica encontrados ao longo do tronco H. vellosoi parece indicar um maior investimento mecânico na base do tronco em comparação com as outras duas alturas (1 e 2 metros), anatomicamente representada por vasos de menor diâmetro e fibras com paredes mais espessas. Consequentemente, um investimento em maior resistência mecânica implica em menor condutividade de água, contudo, mais estudos são necessários para determinar se este valor mais baixo em relação ao 1 e 2 metros representa um efeito significativo no transporte de água ao longo do tronco.

Abstract We studied the relationships among wood anatomy, hydraulic conductivity, density and shear parallel to the grain in the stem of Handroanthus vellosoi trees with the goal to identify possible trade-offs between hydraulic conductivity and mechanical properties. For this study we felled 12 trees with 24-year-old and cut 10-cm-thick disks at three heights: base of the trunk, one meter in height, and two meters in height. We propose that the relationship between hydraulic conductivity and mechanical resistance found along the H. vellosoi trunk indicates greater mechanical investment in the wood at the base of the trunk compared with the other two heights (1 and 2 meters). Anatomically, this would be represented by smaller diameter vessels and fibers with thicker walls. Consequently, strength investment implies lower water conductivity at the stem base. However, more studies are needed to determine whether this lower value with respect to 1 and 2 meters represents a significant effect on water transport along the stem.

The building technique of light wooden framing, i.e., woodframe, represents a great innovative goal of construction, due to the very efficient levels of rationalization of material, operational flexibility and productive agility. In addition, excessive use of natural materials of renewable character in the woodframes, as the wood of planted forests, contributes to sustainability, a desired factor in most modern homes. In recent years, Latin American countries have suffered from the constant housing deficit, which destroys the possibilities of the first property by the neediest populations. Therefore, it is necessary to propagate studies, research and information on industrialized housing construction techniques, such as woodframe. This study focused on the exhibition by a state of the art of this innovative wooden housing typology, emphasizing its advantages, importance, types, and its current panorama in the regions in development stage, such as Latin American countries. Currently, the woodframe is known as a modern wooden residential technique, and it is conquering the public of all kind of economic classes, because of its innovation, lightness, competitive costs, and also by the efficient levels of sustainability, cleanness, assembly time, and rationalization of raw materials.

La técnica de construcción de entramado ligero en madera, i.e., woodframe, representa un gran objetivo innovador, debido a los niveles muy eficientes de racionalización de material, flexibilidad de las operaciones, y agilidad productiva. Además, el uso excesivo de materiales naturales de carácter renovable en los entramados ligeros, como la madera de los bosques plantados, contribuye con la sostenibilidad, un factor deseado en la mayoría de las viviendas modernas. En los últimos años, los países latinoamericanos han sufrido el constante déficit de viviendas, lo que destruye las posibilidades de la primera propiedad de las poblaciones más necesitadas. Por lo tanto, es necesario propagar los estudios, la investigación y la información sobre las técnicas de construcción de viviendas industrializadas, como el entramado ligero en madera. Este estudio se centró en la exposición por un estado del arte de esta innovadora tipología de vivienda en madera, destacando sus ventajas, importancia, tipos y su panorama actual en las regiones en fase de desarrollo, como los países de América Latina. En la actualidad, lo entramado ligero en madera es conocido como una técnica de viviendas en madera moderna, y que está conquistando al público de todas las clases económicas, debido a su innovación, ligereza, costos competitivos, y también por los niveles eficientes de sostenibilidad, limpieza, tiempo de montaje y la racionalización de las materias primas.

RESUMO Determinamos as variações axiais da densidade aparente, resistência ao cisalhamento paralelo à grã e anatomia da madeira de Astronium graveolens, relacionando estas propriedades ao longo do fuste. Cortamos cinco árvores com 20 anos de idade e estudamos amostras próximas da casca na base do tronco, a um, dois e três metros de altura. As variações axiais encontradas no lenho de A. graveolens parecem propiciar um equilíbrio entre a resistência mecânica da madeira na base do fuste pela maior densidade e também pela maior resistência ao cisalhamento devido a maior frequência de raios que contribuem no travamento das células orientadas no sentido vertical evitando assim que o tronco quebre facilmente ao ser flexionado. Pensando na condutividade hidráulica, vasos com menor diâmetro e frequência na base do fuste podem garantir maior segurança ao diminuir a ocorrência de embolismos que poderiam prejudicar o fluxo de água ao longo do fuste.

ABSTRACT We investigated the axial variation of specific gravity, shear parallel to the grain and anatomical features of Astronium graveolens wood and related these properties to the anatomy along the stem. We felled five 20-year-old trees and cut discs from four different stem heights, including stem base, 1 meter, 2 meters and 3 meters, for a total of 20 discs, and studied wood samples near the bark and at the base of trunk. Axial variations found appear to provide a balance between mechanical strength of the wood at stem base by the higher density and higher shear by the increase in ray frequency that contributes to locking the vertical cells and growth rings, thus preventing the stem from easily breaking when bent. For hydraulic conductivity, vessels with smaller diameter and frequency at the stem base help prevent the occurrence of embolisms that would reduce water flow along the main stem.