Cambial growth periodicity studies of South American woody species: A review

This paper reviews histological studies of cambium activity in South American woody species and provides future research prospects. The majority of the studies almost exclusively describe radial increment and/or its periodicity. There are 15 papers concerning the cambial activity of 17 woody species from the South American flora and 3 exotic species in 4 countries that were published to date. Despite endogenous factors affecting the radial meristem, the seasonality of rains has been identified as the main factor influencing cambial activity in the tropics and subtropics. There is a lack of standardization and a need for improvement and discussion concerning the methods used. Moreover, radial growth studies conducted by monitoring cambium cell production are still scarce in South America, especially when considering the high diversity of the continents flora and ecosystems.Fil: Callado, Cátia Henriques. Universidade do Estado do Rio de Janeiro. Departamento de Biologia Vegetal. Laboratório de Anatomia Vegetal; BrasilFil: Roig Junent, Fidel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Tomazello Filho, Mário. Universidade de São Paulo. Escola Superior de Agricultura Luis de Queiroz. Departamento de Ciências Florestais; BrasilFil: Barros, Claudia Franca. Instituto de Pesquisas Jardim Botânico do Rio de Janeiro; Brasi

Domatia and leaf blade structure of Rudgea eugenioides (Rubiaceae)

Rudgea eugenioides is a rare woody species that grows in the understory of well-preserved Atlantic Forest of Serra dos Órgãos, in the state of Rio de Janeiro, Brazil. Leaves were collected in Reserva Ecológica de Macaé de Cima, Rio de Janeiro. The anatomical characteristics of the leaf blade were examined, especially the epidermis, using light and electron microscopy. The abaxial surface was smooth, with gap domatia between the midrib and the secondary veins and papillae. Micromorphological analyses showed epicuticular wax without any ornamentation. Leaf cross sections of R. eugenioides showed that the epidermis consisted of one-layer of cells covered with a fine cuticle and parallelocytic stomata. Light microscopy revealed that the periclinal cell walls were flat and that the anticlinal walls were predominantly straight and thicker. The leaf blade contained dorsiventral mesophyll with crystal idioblasts and collateral vascular bundles. Transmission electron microscopy allowed the arrangement of the outer periclinal cell wall to be observed. The results identified anatomical and ultrastructural characteristics that may contribute to understanding the taxonomy of this species and the survival strategies it uses in this forest environment.Rudgea eugenioides é uma espécie arbórea rara no sub-bosque de florestas bem preservadas da Serra dos Órgãos, na Floresta Atlântica do Estado do Rio de Janeiro, Brasil. Folhas foram coletadas na Reserva Ecológica de Macaé de Cima, Rio de Janeiro e observadas características anatômicas da lâmina foliar, com especial atenção à epiderme, usando microscopia óptica e eletrônica. A superfície abaxial é lisa, apresentando domácias do tipo em fenda entre a nervura principal e as secundárias e papilas. Análises micromorfológicas mostraram filme contínuo de cera sem qualquer ornamentação. Cortes transversais da lâmina foliar de R. eugenioides mostrou epiderme adaxial e abaxial com uma camada de células cobertas com uma cutícula delgada e estômatos paralelocíticos apenas na superfície abaxial. Em microscopia óptica, as paredes periclinais mostraram-se planas e as paredes anticlinais predominantemente retas e espessas. A lâmina foliar apresenta mesofilo dorsiventral com idioblastos cristalíferos e feixes vasculares colaterais. Em microscopia eletrônica de transmissão, foi observado o arranjo da parede periclinal externa. Os resultados identificaram características anatômicas e ultraestruturais que podem ser relevantes para subsidiar a taxonomia e estratégias de sobrevivência no ambiente de floresta

Intraspecific variation of Paubrasilia echinata (Fabaceae) wood along a latitudinal gradient in Brazil

Molecular and taxonomy approach have been made to understand the differences among the three morphotypes of Paubrasilia echinata, termed laranja, café and arruda. However, there is no wood anatomic study considering these morphotypes and their probable anatomical similarity. Considering as an endangered species with historical relevancy, it is crucial to recognize its wood anatomy to its conservation. This study aims to investigate the wood anatomy of P. echinata collected along its occurrence area (between 5°53′S 34°04′W and 22°56′S 42°30′W) and to examine the anatomical relationship among arruda, laranja and café morphotypes that was previously reported by molecular studies. The results indicate that the wood anatomy varied along its range of distribution a gradient of axial parenchyma and vessel features between the lower and higher latitudes was observed. Since arruda occurs in the collection sites of all four states studied, while café and laranja only in Bahia, the three morphotypes can be identified into of two groups based on wood anatomy: one formed by arruda samples and another by café and laranja, which differs from the previous molecular analysis. Combinations between higher percentage of axial parenchyma and wider vessels were observed in samples from RJ guarantying conductance and safety, while samples from RN and PB have smaller solitary vessels and scanty axial parenchyma, which could prevent embolisms. The present results do not support the categorization into subspecies or varieties. The findings also suggest that café and laranja share similar features than with arruda morphotype.publishe

Decay resistance variability of European wood species thermally modified by industrial process

Thermal modification is now considered as a new ecofriendly industrial wood modification process improving mainly the material decay resistance and its dimensional stability. Most industrial thermal treatment processes use convection heat transfer which induces sometimes heterogeneous treatment temperature propagation within the oven and lead to the heterogeneity in treatment efficiency. Thus, it is common that treatment is not completely effective on several stack boards, in a same batch. The aim of this paper was to study the decay resistance variability of various European wood species thermally modified. Thermal modifications were performed around 240°C during 4h, on about 10 m3 of 27 x 152 x 2000 mm3 wood planks placed in an industrial oven having a volume of 20 m3, on the following wood species: spruce, ash, beech and poplar. All of the tests concerning the decay resistance were carried out in the laboratory using untreated beech and pine woods as reference materials. An agar block test was used to determine the resistance of thermally modified woods, leached beforehand according to EN 84 standard or not, to brown-rot and white-rot fungi, according to XP CEN/TS 15083-1. A large selection of treated wood samples was tested in order to estimate the variability of treatment efficiency. Thermal treatment increased the biological durability of all leached and un-leached modified wood samples, compared with native wood species. The treatment temperature of 240°C used in this study is sufficient to reach durability classes ''durable'' or ''very durable'' for the four wood species. However, the dispersion of weight loss values, due to the fungal attacks was very important and showed a large variability of the durability of wood which has been treated in a single batch. These results showed that there is a substantial need to develop process control and² indicator in order to insure that the quality of treated timber is properly evaluated with a view to putting this modified timber on the market under a chain of custody. (Résumé d'auteur

Promoting Responsible Research and Innovation (RRI) During Brazilian Activities of Genomic and Epidemiological Surveillance of Arboviruses

Zika infectio

ZikaPLAN: addressing the knowledge gaps and working towards a research preparedness network in the Americas.

Zika Preparedness Latin American Network (ZikaPLAN) is a research consortium funded by the European Commission to address the research gaps in combating Zika and to establish a sustainable network with research capacity building in the Americas. Here we present a report on ZikaPLAN`s mid-term achievements since its initiation in October 2016 to June 2019, illustrating the research objectives of the 15 work packages ranging from virology, diagnostics, entomology and vector control, modelling to clinical cohort studies in pregnant women and neonates, as well as studies on the neurological complications of Zika infections in adolescents and adults. For example, the Neuroviruses Emerging in the Americas Study (NEAS) has set up more than 10 clinical sites in Colombia. Through the Butantan Phase 3 dengue vaccine trial, we have access to samples of 17,000 subjects in 14 different geographic locations in Brazil. To address the lack of access to clinical samples for diagnostic evaluation, ZikaPLAN set up a network of quality sites with access to well-characterized clinical specimens and capacity for independent evaluations. The International Committee for Congenital Anomaly Surveillance Tools was formed with global representation from regional networks conducting birth defects surveillance. We have collated a comprehensive inventory of resources and tools for birth defects surveillance, and developed an App for low resource regions facilitating the coding and description of all major externally visible congenital anomalies including congenital Zika syndrome. Research Capacity Network (REDe) is a shared and open resource centre where researchers and health workers can access tools, resources and support, enabling better and more research in the region. Addressing the gap in research capacity in LMICs is pivotal in ensuring broad-based systems to be prepared for the next outbreak. Our shared and open research space through REDe will be used to maximize the transfer of research into practice by summarizing the research output and by hosting the tools, resources, guidance and recommendations generated by these studies. Leveraging on the research from this consortium, we are working towards a research preparedness network

Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt