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Gap-graded aggregate combined with asphalt rubber presents a high-performance alternative for roads with heavy traffic loads, offering advantages over conventional mixtures in terms of permanent deformation (rutting), fatigue life, and texture. In this study, the conventional filler in the well-established mixture was substituted with sugarcane bagasse bottom ash (SCBA) at a proportion of 5% of the total mineral aggregates. The objective was to enhance the mechanical performance of the asphalt coating while ensuring proper disposal of this waste material. Compared to conventional filler, SCBA is less dense, has smaller dimensions, and exhibits greater roughness, thereby affecting the volumetric parameters of the Marshall mix design. Consequently, the volume of voids in mineral aggregates and voids filled with asphalt increased while maintaining the same volume of air voids (5.3%). Consequently, there was a notable increase in Marshall Stability (40%) and Indirect Tensile Test (22%) mechanical parameters. Following laboratory analysis, the modified mixtures were applied as asphalt coating on a high-traffic highway (BR-158). Field specimens revealed an 18% increase in the Resilience Modulus (4088 MPa; 3478 MPa). Additionally, its Flow Number exhibited a 73% increase (16,707; 9681), and its permanent deformation rate was 28% lower within 10,000 cycles in the dynamic creep test. This was further supported by an 11% reduction in permanent deformation rate in the Hamburg Wheel Tracking Device (HWTD) within 20,000 cycles (3.2 mm; 3.6 mm). In conclusion, the partial replacement of conventional filler with sugarcane bagasse ash within the established granulometric range has demonstrated technical feasibility both in laboratory and field settings.

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Highway fatalities are a leading cause of death in the U.S. and other industrialized countries. Using highly detailed crash, speed, and flow data, we show highway travel and motor vehicle crashes fell substantially in California during the response to the COVID-19 pandemic. However, we also show the frequency of severe crashes increased owing to lower traffic congestion and higher highway speeds. This "speed effect" is largest in counties with high pre-existing levels of congestion, and we show it partially or completely offsets the "VMT effect" of reduced vehicle miles traveled on total fatalities. During the first eleven weeks of the COVID-19 response, highway driving decreased by approximately 22% and total crashes decreased by 49%. While average speeds increased by a modest 2 to 3 mph across the state, they increased between 10 and 15 mph in several counties. The proportion of severe crashes increased nearly 5 percentage points, or 25%. While fatalities decreased initially following restrictions, increased speeds mitigated the effect of lower vehicle miles traveled on fatalities, yielding little to no reduction in fatalities later in the COVID period.

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This paper proposes a multidimensional and multi-period analysis of safety on roads. It aggregates different road safety performance indicators observed over different periods for which multicriteria and multi-period approaches are used. The criticality of a road depends on the interaction of various factors, such as human factors, causes of accidents and their severity levels, and the characteristics/states of the roads. Therefore, there is a need for a multidimensional view of risk and its consequences concerning traffic accidents. Furthermore, using the Multiple Criteria Decision Making/Aid methods (MCDM/A) allows the performance of roads in the multiple criteria to be considered according to the decision maker's preferences. On the other hand, the temporal approach reflects the performance of roads and their accidents in different periods, enabling the information on the temporal behavior of accidents to be aggregated to the result. Given that Brazil has a vast road network, there is thus the problem of prioritizing road segments to allocate resources for traffic accident prevention and mitigation actions, especially as these resources are usually limited and scarce. For that, a case study is developed in the state of Pernambuco in Brazil. Eleven road segments are analyzed. The strategic objective of the decision-maker is to have a broader view, initially, of the criticality of these road segments in terms of safety so that strategically he can allocate resources to prevent and mitigate the risks of traffic accidents. For this, the decision-maker considered eleven criteria. These represent the different dimensions that can influence traffic accidents, such as the damage (impacts) to human beings or other consequences resulting from traffic accidents and issues related to the characteristics/state of the road and its traffic. Five periods of time were considered to incorporate the temporal influence of these dimensions (2015 to 2019). As a result, it is seen that, for a more comprehensive assessment, it is essential to consider a multidimensional view of risk and a multi-period evaluation, thus incorporating more information into the decision model and thereby making its results more assertive.

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Improving safety culture and safety performance is a constant concern for companies operating in high-risk environments. For almost two decades, IDOCAL (the Research Institute of Personnel Psychology, Organizational Development and Quality of Working Life) has been contributing to advancing our understanding of these important concepts through theoretical development and empirical research. The objective of this article is to synthesize these contributions. Some of the most prominent are (1) the development of a framework for the evaluation of safety culture and its correlates based on the AMIGO model, (2) the establishment of the empowering leadership model as a valuable concept in safety leadership, and (3) the establishment of a three-dimensional safety performance model. In addition, the researchers within IDOCAL have made great progress in understanding the main predictors of safety performance, including empowering leadership and safety culture. Within this paper, IDOCAL's plans to advance this line of research in the coming years, by extending it from the nuclear power sector to other high-risk industries, are also outlined.

Melhorar a cultura de segurança e o desempenho de segurança é uma preocupação constante para empresas que operam em ambientes de alto risco. Há quase duas décadas, o IDOCAL (Instituto de Pesquisa em Psicologia do Pessoal, Desenvolvimento Organizacional e Qualidade de Vida no Trabalho) tem contribuído para o avanço da compreensão desses importantes conceitos por meio do desenvolvimento teórico e da pesquisa empírica. O objetivo deste artigo é sintetizar essas contribuições. Alguns dos mais proeminentes são (1) o desenvolvimento de uma estrutura para a avaliação da cultura de segurança e seus correlatos com base no modelo AMIGO, (2) o estabelecimento do modelo de liderança capacitadora como um conceito valioso em liderança de segurança, e (3) o estabelecimento de um modelo tridimensional de desempenho de segurança. Além disso, os pesquisadores do IDOCAL fizeram um grande progresso no entendimento dos principais preditores de desempenho de segurança, incluindo capacitação de liderança e cultura de segurança. Neste documento, os planos do IDOCAL para avançar esta linha de pesquisa nos próximos anos, estendendo-a do setor de energia nuclear a outras indústrias de alto risco, também são descritos.

Mejorar la cultura de la seguridad y el desempeño de seguridad es una preocupación constante para las empresas que operan en entornos de alto riesgo. Durante casi dos décadas, IDOCAL (el Instituto de Investigación en Psicología de los Recursos Humanos, Desarrollo Organizacional y Calidad de Vida Laboral) ha contribuido a mejorar nuestra comprensión de estos importantes conceptos a través del desarrollo teórico y la investigación empírica. El objetivo de este artículo es sintetizar estos aportes. Algunos de los más destacados son (1) el desarrollo de un marco para la evaluación de la cultura de la seguridad y sus correlatos basado en el modelo AMIGO, (2) el establecimiento del modelo de liderazgo empoderador como un concepto valioso en el liderazgo en seguridad, y (3) el establecimiento de un modelo tridimensional de desempeño de seguridad. Además, los investigadores de IDOCAL han logrado grandes avances en la comprensión de los principales predictores del desempeño en seguridad, incluido el liderazgo de empoderamiento y la cultura de seguridad. En este trabajo también se describen los planes de IDOCAL para avanzar en esta línea de investigación en los próximos años, extendiéndola desde el sector de la energía nuclear a otras industrias de alto riesgo.

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Se presenta este artículo de revisión con base en la evidencia científica actual sobre medicina espacial enfocada en fisiología humana y sus contramedidas. Por lo cual se realizó una búsqueda bibliográfica no sistemática de artículos científicos y libros de investigación en inglés-español de los últimos 7 años, que detallan su aplicación en seres humanos, modelos murinos y experimentos in vitro. Se tomaron en cuenta las condiciones del ambiente espacial como microgravedad y radiación que producen considerables cambios fisiológicos en el sistema cardiovascular (redistribución de líquidos, remodelación cardiovascular, arritmias); nervioso (sensitivomotores, neurosensoriales, neurovestibulares); respiratorio (cambios de volúmenes y capacidades); renal (litiasis); musculoesquelético (atrofia muscular, osteoporosis); hematológico (anemia); inmunológico (desregulación inmune) y digestivo (alteración de la microbiota intestinal). Además, existen procesos biológicos, moleculares y genéticos aún por explorar, para conocer y mitigar los mecanismos inciertos desencadenados en ambientes extremos y peligrosos. Por lo tanto, es una prioridad desarrollar e implementar contramedidas para reducir los efectos nocivos en la salud, con el objetivo de garantizar la adaptación, seguridad y performance del astronauta durante futuros viajes espaciales.

This Review Article is presented based on current scientific evidence on space medicine focused on human physiology and its countermeasures. Therefore, a non-systematic bibliographic search of scientific articles and research books in English-Spanish of the last 7 years was carried out, detailing their application in humans, murine models and in vitro experiments. The conditions of the space environment such as microgravity and radiation that produce considerable physiological changes in the cardiovascular system (redistribution of fluids, cardiovascular remodeling, arrhythmias) were taken into account; nervous (sensorimotor, neurosensory, neurovestibular); respiratory (volume and capacity changes); renal (lithiasis); musculoskeletal (muscular atrophy, osteoporosis); hematological (anemia); immunological (immune dysregulation) and digestive (intestinal microbiota disorder). In addition, there are biological, molecular and genetic processes still to be explored, in order to know and mitigate the uncertain mechanisms triggered in extreme and dangerous environments. Therefore, it is a priority to develop and implement countermeasures to reduce the harmful effects on health, with the aim of guaranteeing the astronaut's adaptation, safety and performance during future space flights.

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Although complexity and resilience are key inter-related characteristics of construction projects, little is known on how to monitor these characteristics and their implications for safety management. This study investigates the contribution of Safety Performance Measurement Systems (SPMS) as a means for monitoring and understanding of sources of complexity and resilience in construction. It is based in three empirical studies carried out in construction projects, two in Chile and one in Brazil. Two main tools were applied in these studies: (i) the Technical, Organizational and Environmental (TOE) framework, focused on complexity; and (ii) the Resilience Assessment Grid (RAG), focused on resilience. Improvement opportunities were identified for existing SPMS. Also, a set of guidelines for the design of SPMS emerged from these studies as well as a model that explains the connections between the main constructs encompassed by the guidelines.

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Generalized Linear Models (GLM) with negative binomial distribution for errors, have been widely used to estimate safety at the level of transportation planning. The limited ability of this technique to take spatial effects into account can be overcome through the use of local models from spatial regression techniques, such as Geographically Weighted Poisson Regression (GWPR). Although GWPR is a system that deals with spatial dependency and heterogeneity and has already been used in some road safety studies at the planning level, it fails to account for the possible overdispersion that can be found in the observations on road-traffic crashes. Two approaches were adopted for the Geographically Weighted Negative Binomial Regression (GWNBR) model to allow discrete data to be modeled in a non-stationary form and to take note of the overdispersion of the data: the first examines the constant overdispersion for all the traffic zones and the second includes the variable for each spatial unit. This research conducts a comparative analysis between non-spatial global crash prediction models and spatial local GWPR and GWNBR at the level of traffic zones in Fortaleza/Brazil. A geographic database of 126 traffic zones was compiled from the available data on exposure, network characteristics, socioeconomic factors and land use. The models were calibrated by using the frequency of injury crashes as a dependent variable and the results showed that GWPR and GWNBR achieved a better performance than GLM for the average residuals and likelihood as well as reducing the spatial autocorrelation of the residuals, and the GWNBR model was more able to capture the spatial heterogeneity of the crash frequency.

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This paper presents a modeling effort for developing safety performance models (SPM) for urban intersections for three major Brazilian cities. The proposed methodology for calibrating SPM has been divided into the following steps: defining the safety study objective, choosing predictive variables and sample size, data acquisition, defining model expression and model parameters and model evaluation. Among the predictive variables explored in the calibration phase were exposure variables (AADT), number of lanes, number of approaches and central median status. SPMs were obtained for three cities: Fortaleza, Belo Horizonte and Brasília. The SPM developed for signalized intersections in Fortaleza and Belo Horizonte had the same structure and the most significant independent variables, which were AADT entering the intersection and number of lanes, and in addition, the coefficient of the best models were in the same range of values. For Brasília, because of the sample size, the signalized and unsignalized intersections were grouped, and the AADT was split in minor and major approaches, which were the most significant variables. This paper also evaluated SPM transferability to other jurisdiction. The SPM for signalized intersections from Fortaleza and Belo Horizonte have been recalibrated (in terms of the Cx) to the city of Porto Alegre. The models were adjusted following the Highway Safety Manual (HSM) calibration procedure and yielded Cx of 0.65 and 2.06 for Fortaleza and Belo Horizonte SPM respectively. This paper showed the experience and future challenges toward the initiatives on development of SPMs in Brazil, that can serve as a guide for other countries that are in the same stage in this subject.

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