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Vector control is one of the principal strategies used for reducing malaria transmission. Long-lasting insecticidal bed nets (LLINs) are a key tool used to protect populations at risk of malaria, since they provide both physical and chemical barriers to prevent human-vector contact. This study aimed to assess the physical durability and insecticidal efficacy of LLINs distributed in Cruzeiro do Sul (CZS), Brazil, after 4 years of use. A total of 3000 LLINs (PermaNet 2.0) were distributed in high malaria risk areas of CZS in 2007. After 4 years of use, 27 'rectangular' LLINs and 28 'conical' LLINs were randomly selected for analysis. The evaluation of physical integrity was based on counting the number of holes and measuring their size and location on the nets. Insecticidal efficacy was evaluated by cone bioassays, and the amount of residual insecticide remaining on the surface of the LLINs was estimated using a colorimetric method. After 4 years of use, physical damage was highly prevalent on the rectangular LLINs, with a total of 473 holes detected across the 27 nets. The upper portion of the side panels sustained the greatest damage in rectangular LLINs. The overall mosquito mortality by cone bioassay was < 80% in 25/27 rectangular LLINs, with panel A (at the end of the rectangular bednet) presenting the highest mortality (54%). The overall mean insecticide concentration was 0.5 µg/sample, with the bednet roof containing the highest average concentration (0.61 µg/sample). On the conical LLINs, 547 holes were detected, with the bottom areas sustaining the greatest damage. The cone bioassay mortality was < 80% in 26/28 of the conical LLINs. The mean insecticide concentration was 0.3 µg/sample. After 4 years of use, the insecticidal efficacy of the LLINs was diminished to below acceptable thresholds. [ABSTRACT FROM AUTHOR]

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Flower stems of the Heliconiaceae family are gaining more and more space in the Brazilian market of ornamental plants and further knowledge about quality, productivity, and postharvest management is necessary. The objective of the present study was to evaluate heliconiaceae cultivated in full sun in the central-west region of Brazil in terms of agronomic traits and to determine the postharvest durability of floral stems submitted to cold storage. Accessions of Heliconia bihai cultivar Caribea, H. bihai cultivar Iris Red, and H. rauliniana were evaluated. Quantitative and qualitative morphological characteristics, the total number of flower stems produced, and number of marketable stems were obtained. Postharvest longevity was tested in a cold chamber at 16 °C and 19 °C and at ambient temperature of 26 °C. Morphological characteristics such as the length, diameter and fresh mass of flower stems, inflorescence length, and postharvest durability of the inflorescences were the most affected. The most important variables were the quality of flower stems, productivity of marketable stems, and postharvest durability. The studied heliconias presented agronomic characters within the commercialization standards, highlighting H. bihai (Caribea) which presented the highest productivity. The best storage temperature for all accessions evaluated was 16 °C. [ABSTRACT FROM AUTHOR]

The journal Gazeta do Rio de Janeiro, the first one produced in Brazil regularly, was one of the historiographical objects most mistreated by the historiography of communication on 20th century. Read by eyes of the political contest, it was reduced to an irrelevant spreader of the life and values of the Portuguese monarchy, deserving low concern for being irrelevant. These points of view approached the object from the outside, analyzing it by external factors such as its binding to the king. Monarchical journal, it was read by the eyes of the Republic. Rescued by actual historiography, it has been reread for its role in itself, not for the role that the present hoped, chronocentricly, for it to play. With an approach focused on discursive materiality and unraveling its real conditions of existence and communicational operation, this article looks inside of it, without judging, trying to understand Gazeta and its undeniable relevance on its time, either for its durability or for the type of press that it created in Brazil. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Climatología is the property of Revista de Climatologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• A technical and economic analysis of PV panels with and without a cooling system is presented. • Analysis of the cooling effects on the efficiency and durability of PV panels is performed. • A standard system has been designed to cool down the PV modules. • Efficiency and durability within a 25 years lifetime of a PV panel are predicted. • Initial investments on cooling down PV system are compensated over its lifetime. Photovoltaic (PV) panels can increase their efficiency and durability by using water-cooled systems. In this paper, the authors present a methodology to establish the degradation rate (DR) of PV panels related to their durability and efficiency under cooled versus no-cooled conditions. A long-term feasibility analysis of PV power plants with some suggested modifications are discussed in detail. A standard system was designed to cool down the PV modules. The simulations used with this purpose are based on several publications with relevant aspects carried out in the literature using Matlab-based modeling data. Such results were then confirmed by Homer program to predict the efficiency and durability of PV panels within a lifetime period of 25 years. To illustrate the methodology proposed here, the simulation parameters were used for the city of Santa Maria-RS, Brazil. The results allowed to conclude that cooling combined with heated water for domestic usage can decrease the PV degradation rate by 3% and provide an increased efficiency by almost 30% with respect to the PV panels without such cooling approaches. Therefore, the final results conclude that installation of water-cooled PV panels is an attractive and feasible option for a short- and long-term efficiency improvement with great impact on the expansion and durability of PV power plants. [ABSTRACT FROM AUTHOR]

This article presents a study on durability index obtained in the slake durability test (SDT) and the uniaxial compressive strength (UCS) of a gneissic rock from the Nova Venécia Complex, southeastern Brazil. The gneissic rock mass, excavated for a railway tunnel without a lining, has presented problems of instability of blocks due to a long-term exposure to weathering. The characterization of the gneissic rock matrix was made tactile and visual and by means of microscopical petrography, combining the tests of physical properties, SDT, and UCS with weathering indexes. The importance of describing the heterogeneity of the gneissic rock to interpret its influence on geotechnical parameters is discussed deeply. The interpretation of the results indicates that the rock studied has one facies with greater susceptibility to weathering, loss of strength, and durability. This study also proposes an equation to access the alterability parameter, recently added in the 2014 update of the rock mass rating (RMR), which may be overvalued to crystalline rocks, as observed in the analysis. [ABSTRACT FROM AUTHOR]

• AAS showed higher carbonation than Portland cement. • The carbonation of AAS was related to intense shrinkage and absence of Ca(OH) 2. • GBFS from charcoal was unable to reduce the susceptibility of AAS to carbonation. In Brazil, 20% of annual steel production is from charcoal, with growth prospects due to the increase in the use of charcoal as a substitute for coke. The slags from coal blast furnaces (coke) have a large percentage of CaO to remove the present sulfur while those produced in charcoal blast furnaces have a low CaO-SiO 2 ratio. Alkali-activated slag (AAS) is a type of cement obtained mostly from GBFS, which has good mechanical properties for engineering and low environmental impact in its production process. This process is based on the activation of the slag by an alkaline solution, such as hydroxides or silicates. However, because the product of hydration consists essentially of CASH, carbonation in AAS has been investigated. Also, studies dedicated to AAS from charcoal (low CaO/SiO 2) are not common. Therefore, the goal of this paper was to study the behavior of GBFS-based AAS from charcoal under carbonated conditions by accelerated tests and compare it with that of Portland cement. The results showed that AAS presented higher carbonation depths (127.1 mm) than Portland cement (PC) (77.1 mm) and a sharp decrease in compressive strength from 37 to 28 MPa, which was related to intense shrinkage, decalcification of CSH and formation of vaterite. Although the slag from charcoal has more Al 2 O 3 (13%) and MgO (6%), it was unable to form aluminosilicate or hydrotalcite, which could reduce the susceptibility of AAS carbonation. [ABSTRACT FROM AUTHOR]

The evaluation of the durability of materials and of construction systems involves the identification of several agents that attack the environment, in tropical countries, such as Brazil, climatic factors tend to intensify the problems related to the durability of constructive elements. The façade of buildings are the ones that suffer the most from climate change, as they oscillate between large exposures of solar radiation and cooling, a function exerted by rainfall. It is proposed in this study comparisons between results of tests of resistance to heat and thermal shock in façades of buildings, in which it is described in the performance standard - NBR 15575-4 (ABNT, 2013). Most of the results were positive in some test specimens, that is, in the tests of the specimens in question, it was possible to attend to the standard, however a revision of the test method established in the standard is proposed, so that the normative details can meet with more precise the elements tested. [ABSTRACT FROM AUTHOR]

• ASR susceptibility on concrete coarse aggregates from a Brasilian Shear Zone. • ASR potential of coarse concrete aggregate through petrographic analysis, AMBT, ACPT and MCPT. • Petrographic examination reveal potentially reactive aggregates. • ABMT resulted in expansions of 0.19% at 14 days and 0.32% at 28 days. • Concrete tests reveal moderately reactive aggregate. Being the fifth largest country globally, Brazil has a wide variety of rocks used in concrete production. Due to their mineralogical characteristics, many Brazilian rocks present reactive alkali potential, mainly due to the strong presence of silica and/or silicates in their composition. Alkali silica reaction (ASR) was firstly public in Brazil in 1963 in the Jupiá dam. Since then, several ASR events have been reported, namely in Dam and electric power plants, which represent a concern, mainly due to those infrastructures' social, economic, and environmental impact. Even though the selection of the raw materials should consider the aggregate quality and adequacy for a certain application, it mostly depends on the local availability due to economic reasons. Thus, an effective way to evaluate ASR susceptibility on concrete aggregates and predict or prevent the in situ behaviour of the final concrete product properties is crucial. This is particularly important when aggregates sources are Shear Zones, such as Pernambuco East Shear Zone. International standards suggested evaluating aggregate susceptibility prone to ASR through petrographic analysis of aggregates in addition to expansion tests at mortar and/or concrete levels. Concrete prism tests (CPT) are considered the most reliable method for ASR potentially of concrete aggregates; however, CPT are very time consuming, and results might be available after one year. Thus, Brazilian Association for Standardisation suggested a new accelerated concrete test based on RILEM recommendation AAR-4.1, the NBR 15577-7. This work evaluated the behaviour of the coarse aggregate obtained from ZCPE, to prone ASR among different testing conditions proposed by most widespread international standards, namely, petrographic examination, ASTM C 1260, RILEM AAR-4.1, ASSTHO T 380 and NBR 15577-7. Then results were compared and discussed the applicability of the new national standard NBR 15577-7. According to petrographic examination, the coarse aggregate from Pernambuco East Shear Zone was potentially reactive. Expansion tests at mortar and concrete levels corroborated such results, and coarse aggregate was classified as potentially reactive among all standards followed. Thus, it can be concluded that the new NBR 15577-7 outputs similar results compared to other international standards and seems to be a faster way (20 weeks/140 days) to access the ASR potential of reactive aggregates. [ABSTRACT FROM AUTHOR]

The grapevine breeding for disease resistance is a strategy to promote the viticulture sustainability worldwide. Due the perennial nature of grapevine, it is essential that the genetic resistance should be durable. However, biotrophic pathogens with a mixed reproduction systems associated with heterotalism, such as Plasmopara viticola, the causal agent of grapevine downy mildew, have a high evolutionary potential that confers a strong capacity to overcome resistance mechanisms. Thus, the main aim of this work was to evaluate the level of adaptation of P. viticola populations to resistant grape varieties/genotypes carrying different combinations of R-Gene alleles in Santa Catarina state, Brazil. For this purpose, P. viticola inocula were collected from two sites of the State (Curitibanos and Urussanga) in the year of 2021. The inoculum was composed of a mixture of sporangia sampled at the end of the grapevine cycles, from hosts containing the R-alleles Rpv3, Rpv10, Rpv1+3, Rpv3+10. The sporangia suspension was prepared from each population and used in cross inoculations using leaf discs of the susceptible variety Cabernet Sauvignon and a panel of ten cultivars/genotypes containing different R-alleles combinations (Rpv3.1, Rpv3.1+3.2, Rpv3.1+3.3, Rpv1+3.1, Rpv10, Rpv10+3.3, Rpv10+3.1+3.3, Rpv12 and Rpv12+3.1). At six days after cross-inoculation (dai), disease severity, resistance level (OIV 452-1 descriptor) and sporulation incidence were evaluated; at 7 dai, sporangia production was measured. The data obtained were subjected to analysis of normality and variance, followed by the Freedman, Dunn's and Tukey tests. The Rpv12 allele was the most effective source of resistance, limiting completely the sporulation of the pathogen. Rpv10 allele was also highly efficient, and no additive effect was observed when combined with the Rpv3 allele. In addition, an erosion of the resistance conferred by Rpv3 allele was observed, manifested as a dense sporulation as Cabernet Sauvignon. However, when Rpv3 was combined with Rpv1, a high level of resistance was generally observed. Isolates collected from Curitibanos and Urussanga were able to sporulate in host carrying Rpv1+3, and Rpv3+10, bringing concerns about the durability. This knowledge is fundamental for the definition of breeding strategies for the release of grapevine varieties with durable resistance. [ABSTRACT FROM AUTHOR]

During the assessment programme of Brazilian roadway bridges, it was noticed that two girder-slab reinforced concrete bridges, with cantilever girders on extremity spans, were a common structural solution adopted 40 years ago in Brazil. Particularities intrinsic to these systems like significant displacements expected on cantilevers associated with soil embankment settlement in bridge entrance can take to a sudden change in slope grades near its ends, provoking sometimes high impact factors. Besides that, traffic and axle load increase has been of concern because these bridges were designed with different scenarios 40 years ago. Therefore, these facts can affect the structural performance of these structures in face of 100 years life required on most current codes for new bridges. So, in this article, a safety assessment to this assembly of bridges is performed. For this study, a simulation model has been developed, which includes the most significant sources of uncertainty in the definition of traffic action and structural response of bridges. Database provided by dynamic tests of these bridges were used for this performance-based assessment. As a result, reliability indexes to fatigue and ultimate limit state of bending are calculated and compared with target values as specified by codes. [ABSTRACT FROM PUBLISHER]

The durability of unplasticized poly(vinyl chloride) (uPVC) components used in the building industry is a function of the interaction of several factors. Types and quantities of additives incorporated to the PVC resin and defining the formulation of the PVC compound used in the production of these components are among the most important such factors. White uPVC window profiles with different formulations have been exposed to five years of natural weathering under Brazilian climatic conditions. Results of Charpy impact tests were used to assess the influence of three factors on the durability of the profiles: additivation levels of titanium dioxide, nature of the impact modifier, and nature of the thermal stabilizer. Statistical analysis of the results made it possible to rank these factors according to their influence in component durability. The influence of composition of uPVC on mechanical properties of window profiles is demonstrated by means of the study of the modulus of elasticity. Results presented in this paper indicated the need for several additional experiments in order to check changes in molecular mass and color. Comparison of all these data with results from profiles subjected to accelerated weathering led to straightforward criteria for prediction of the potential behavior of uPVC, to be described in a future paper. [ABSTRACT FROM AUTHOR]

Background: The duration of protection against tuberculosis provided by isoniazid preventive therapy is not known for human immunodeficiency virus (HIV)-infected individuals living in settings of medium tuberculosis incidence., Methods: We conducted an individual-level analysis of participants in a cluster-randomized, phased-implementation trial of isoniazid preventive therapy. HIV-infected patients who had positive tuberculin skin tests (TSTs) were followed until tuberculosis diagnosis, death, or administrative censoring. Nelson-Aalen cumulative hazard plots were generated and hazards were compared using the log-rank test. Cox proportional hazards models were fitted to investigate factors associated with tuberculosis diagnosis., Results: Between 2003 and 2009, 1954 patients with a positive TST were studied. Among these, 1601 (82%) initiated isoniazid. Overall tuberculosis incidence was 1.39 per 100 person-years (PY); 0.53 per 100 PY in those who initiated isoniazid and 6.52 per 100 PY for those who did not (adjusted hazard ratio [aHR], 0.17; 95% confidence interval [CI], .11-.25). Receiving antiretroviral therapy at time of a positive TST was associated with a reduced risk of tuberculosis (aHR, 0.69; 95% CI, .48-1.00). Nelson-Aalen plots of tuberculosis incidence showed a constant risk, with no acceleration in 7 years of follow-up for those initiating isoniazid preventive therapy., Conclusions: Isoniazid preventive therapy significantly reduced tuberculosis risk among HIV-infected patients with a positive TST. In a medium-prevalence setting, 6 months of isoniazid in HIV-infected patients with positive TST reduces tuberculosis risk over 7 years of follow-up, in contrast to results of studies in higher-burden settings in Africa., (© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)