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1.
Front Psychol ; 15: 1363922, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774721

RESUMO

Background: In a short time, the COVID-19 pandemic has exerted a huge impact on many aspects of people's lives with a number of consequences, an increase in the risks of psychological diseases being one of them. The aim of this experimental study, based on an eighteen-month follow-up survey, is to assess the psychological effects of the COVID-19 pandemic, in particular, changes in stress, anxiety and depression levels, and the risks of developing Post-Traumatic Stress Disorder (PTSD). Methods: A follow-up survey was performed on a sample of 184 Italian individuals to collect relevant information about the psychological impact of COVID-19. Predictors of the components of the psychological impact were calculated based on the ANCOVA model. Results: The analysis of the online questionnaires led to the conclusion that a high percentage of the participants suffer from levels of stress, anxiety and depression higher than normal as well as an increased risk of PTSD. The severity of such disorders significantly depends on gender, the loss of family members or acquaintances due to the pandemic, the amount of time spent searching for COVID-19 related information, the type of information sources and, in part, on the level of education and income. The time factor had a more severe effect on the low-income population. Conclusion: COVID-19 has entailed a very strong psychological impact on the Italian population also depending on the coping strategies adopted, the level of mindful awareness, socio-demographic variables, people's habits and the way individuals use the available means of communication and information.

2.
Data Brief ; 46: 108781, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36478682

RESUMO

The dataset derives from a thorough laboratory characterization of all existing stabilization technologies suitable for coarse-graded aggregates. They include two traditional binders (based on cement and bitumen) and eleven nontraditional binders (based on brine salt, clay, organic non-petroleum, organic petroleum and synthetic polymer). The dataset derives from four laboratory test operations: repeated load triaxial test performed both before and after exposing the investigated samples to ten freeze-thaw cycles, weight measurement of Marshall specimens during ten freeze-thaw cycles and a modified version of rolling bottle test. Repeated load triaxial tests assess the resilient modulus and the resistance to permanent deformation of both unstabilized and stabilized specimens. The mass loss of Marshall specimens expresses the susceptibility of each additive to lose its binding property when exposed to freezing action. The modified version of the rolling bottle test characterizes the propensity to stripping for each additive coating the aggregates subjected to mechanical stirring action. Given the surging necessity to improve the construction and maintenance operations for road pavements worldwide, this dataset containing information about several stabilization technologies can be very useful for transport agencies, contractors, industry and university researchers as well as companies manufacturing and supplying stabilization technologies.

3.
Materials (Basel) ; 15(12)2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35744385

RESUMO

To develop a mechanistic-empirical pavement design system for Norwegian conditions, this paper evaluates the influence of the adoption of different models and shifting techniques on the determination of dynamic modulus master curves of asphalt mixtures. Two asphalt mixture types commonly used in Norway, namely Asphalt Concrete (AC) and Stone Mastic Asphalt (SMA) containing neat bitumen and polymer-modified bitumen, were prepared by the roller compactor, and their dynamic moduli were determined by the cyclic indirect tensile test. The dynamic modulus master curves were constructed using the standard logistic sigmoidal model, a generalized logistic sigmoidal model and the Christensen-Anderson-Marasteanu model. The shifting techniques consisted of log-linear, quadratic polynomial function, Arrhenius, William-Landel-Ferry and Kaelble methods. The absolute error, normalised square error and goodness-of-fit statistics encompassing standard error ratio and coefficient of determination were used to appraise the models and shifting methods. The results showed that the standard logistic sigmoidal model and the Williams-Landel-Ferry equation had the most suitable fits for the specimens tested. The asphalt mixtures containing neat bitumen had a better fit than the ones containing polymer-modified bitumen. The Kaelble equation and log-linear equation led to similar results. These findings provide a relevant recommendation for the mechanistic-empirical pavement design system.

4.
Materials (Basel) ; 15(1)2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35009462

RESUMO

The microwave heating/healing technique is regarded as a green maintenance approach for asphalt pavements thanks to its promising environmental and economic benefits. However, the main concern about this technology is represented by the possible aging effect generated on bituminous binders. Currently, there is a significant lack of studies dealing with this topic. Based on these premises, the main purpose of this study is to appraise the feasibility of implementing microwave-based maintenance operations considering the associated aging effect. The assessment of fatigue life after cyclic microwave heating (MH) based on a linear amplitude sweep (LAS) test and the changes in the chemical groups detected through Fourier transform infrared (FTIR) spectroscopy document the aging phenomenon. The results indicate that the microwave aging degree on bituminous binder is nonlinear with MH cycles. The microwave radiation causes a distinct aging impact on binders during the first 10 cycles, then the values become constant. Furthermore, a feasibility analysis of MH technology is developed, encompassing four main multidisciplinary aspects: evaluation of microwave aging degree, working mechanism of MH equipment, safety assessment, and economic and ecological considerations. Despite the associated aging issue, the MH method is an efficient technology, considering its various advantages (i.e., rapidity of execution, uniform and non-pollutant treatment, and deep penetration). Meanwhile, the use of steel slag as a microwave absorber bolsters the sustainability of MH technology. This study provides a new perspective to evaluate the microwave heating technique in road engineering comprising the generated aging effect. Practice-oriented recommendations are also formulated regarding the safe implementation of MH technical operations.

5.
Materials (Basel) ; 15(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35057337

RESUMO

Recycled Excavation Materials (REM) are becoming viable alternative construction resources due to their economic benefits. However, REM may be composed of weak rocks, e.g., phyllites, limiting the use in a base layer. The present paper attempts to further the knowledge of the mechanical performance of REM by performing Repeated Load Triaxial Tests (RLTT). REM are mixed with Recycled Phyllite Materials (RPM) in systematic blends of 0%, 25%, 50%, and 100%. The batches' resilient modulus (MR) and permanent deformation (PD) characteristics were assessed to establish the maximum RPM allowed into REM while maintaining the required performance. Hicks and Monismith's and Uzan's models were used to characterize the stiffness behavior. A wide variation in the stiffness between the two materials was observed. Batches comprised of 0% RPM-100% REM and 25% RPM-75% REM showed high stiffness performance. The Coulomb model assessed the PD behavior, and the results showed a similar response for all batches. Unlike the stiffness, blended mixtures did not show sensitivity to increased RPM content in the PD. This study may help end-users to understand the performance of REM given the documented threshold on the allowable quantity of RPM in REM.

6.
Data Brief ; 40: 107758, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35005147

RESUMO

The dataset revolves around the laboratory testing of an innovative additive technology for possible stabilization of unbound courses in road pavements. The product is a synthetic fluid based on isoalkane and tall oil pitch. Two test types are performed. Repeated load triaxial tests evaluate the elastic stiffness and the deformation properties of both untreated and treated aggregates. Moreover, some specimens are also tested before and after being subjected to freezing-thawing actions. A modified version of the rolling bottle test appraises the integrity with stripping loss on loose aggregates covered by the additive. Considering the necessity for road maintenance and rehabilitation worldwide, experimental data dealing with the stabilization potential of an innovative synthetic fluid stabilizer can be relevant for several road stakeholders.

7.
Data Brief ; 41: 107898, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35198678

RESUMO

The collected dataset derives from the laboratory testing of bentonite clay investigated as a stabilization technology for the unbound layers of road pavements. The effect of two kinds of bentonite (calcium based and sodium based) are assessed on two aggregate types commonly used as road construction materials. The investigation program, performed by means of repeated load triaxial tests, encompasses the different combinations of bentonite and aggregate types; two replicate specimens are tested dried for each condition. Considering the global need for ensuring well-performing road infrastructures while employing environmentally sound construction technologies, this dataset documenting the potential of bentonite clays used as road stabilizers can be of interest for several road stakeholders.

8.
Ambio ; 51(3): 531-545, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34155609

RESUMO

As largely documented in the literature, the stark restrictions enforced worldwide in 2020 to curb the COVID-19 pandemic also curtailed the production of air pollutants to some extent. This study investigates the perception of the air pollution as assessed by individuals located in ten countries: Australia, Brazil, China, Ghana, India, Iran, Italy, Norway, South Africa and the USA. The perceptions towards air quality were evaluated by employing an online survey administered in May 2020. Participants (N = 9394) in the ten countries expressed their opinions according to a Likert-scale response. A reduction in pollutant concentration was clearly perceived, albeit to a different extent, by all populations. The survey participants located in India and Italy perceived the largest drop in the air pollution concentration; conversely, the smallest variation was perceived among Chinese and Norwegian respondents. Among all the demographic indicators considered, only gender proved to be statistically significant.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Humanos , Pandemias , Material Particulado/análise , Percepção , SARS-CoV-2
9.
Materials (Basel) ; 14(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065577

RESUMO

Segregation of waste crumb rubber powder (WR) modified asphalt binders the large-scale application of WR in asphalt. The method of microwave activation combined with chemical activation (KMWR) was proposed to improve storage stability and rheological properties of WR modified asphalt in this work. Storage stability and rheological properties of virgin asphalt, MWR modified asphalt, and KMWR modified asphalt were comparatively studied by the standard segregation test, bending beam rheometer (BBR) test, and dynamic shear rheometer (DSR) test. The effect of composite activation on waste rubber powder particles was studied by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET) tests. The main results showed that after the physical and chemical composite activation, the storage stability of waste rubber powder modified asphalt was significantly improved, WR modified asphalt had better crack resistance, better rutting resistance, and better fatigue performance. After physical and chemical activation, WR was desulfurized, and a large number of active groups was grafted on the WR particles.

10.
Data Brief ; 34: 106735, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33506082

RESUMO

The dataset deals with the mechanical characterization of sedimentary rocks collected along the banks of Longyear river in proximity of Longyearbyen (Svalbard) at the junction of Bolterdalen and Adventdalen valleys. As the rocks represent possible local construction materials that can be employed in the new road infrastructures located in the Svalbard archipelago, three types of laboratory investigations were performed for mechanical characterization: Los Angeles tests, micro-Deval tests and repeated load triaxial tests. The grading curve of the material characterized with the repeated load triaxial tests corresponded to a typical one commonly adopted in Norway for road base layer (0-31.5 mm). The dataset offers a thorough overview of the mechanical properties relevant for road constructions and the dataset can be useful to both contractors and transportation agencies operating in the Svalbard archipelago.

11.
J Affect Disord ; 283: 36-51, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33516085

RESUMO

BACKGROUND: In a short time, the COVID-19 pandemic turned into a global emergency. The fear of becoming infected and the lockdown measures have drastically changed people's daily routine. The aim of this study is to establish the psychological impact that the COVID-19 pandemic is entailing, particularly with regards to levels of stress, anxiety and depression, and to the risks of developing Post-Traumatic Stress Disorder (PTSD). METHODS: The study, carried out with a sample of 1612 subjects distributed in seven countries (Australia, China, Ecuador, Iran, Italy, Norway and the United States), allowed us to collect information about the psychological impact of COVID-19. RESULTS: The findings of this study show that the levels of stress, depression and anxiety, as well as the risks of PTSD, are higher than average in over half of the considered sample. The severity of these disorders significantly depends on gender, type of outdoor activities, characteristics of their homes, eventual presence of infected acquaintances, time dedicated to looking for related information (in the news and social networks), type of source information and, in part, to the level of education and income. CONCLUSIONS: We conclude that COVID-19 has a very strong psychological impact on the global population. This appears to be linked to the coping strategies adopted, level of mindful awareness, socio-demographic variables, people's habits and the way individuals use means of communication and information.


Assuntos
COVID-19 , Pandemias , Ansiedade , Austrália , China , Controle de Doenças Transmissíveis , Depressão , Humanos , Irã (Geográfico) , Itália , Noruega , SARS-CoV-2 , Estresse Psicológico
12.
PLoS One ; 16(2): e0245886, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33524042

RESUMO

The restrictive measures implemented in response to the COVID-19 pandemic have triggered sudden massive changes to travel behaviors of people all around the world. This study examines the individual mobility patterns for all transport modes (walk, bicycle, motorcycle, car driven alone, car driven in company, bus, subway, tram, train, airplane) before and during the restrictions adopted in ten countries on six continents: Australia, Brazil, China, Ghana, India, Iran, Italy, Norway, South Africa and the United States. This cross-country study also aims at understanding the predictors of protective behaviors related to the transport sector and COVID-19. Findings hinge upon an online survey conducted in May 2020 (N = 9,394). The empirical results quantify tremendous disruptions for both commuting and non-commuting travels, highlighting substantial reductions in the frequency of all types of trips and use of all modes. In terms of potential virus spread, airplanes and buses are perceived to be the riskiest transport modes, while avoidance of public transport is consistently found across the countries. According to the Protection Motivation Theory, the study sheds new light on the fact that two indicators, namely income inequality, expressed as Gini index, and the reported number of deaths due to COVID-19 per 100,000 inhabitants, aggravate respondents' perceptions. This research indicates that socio-economic inequality and morbidity are not only related to actual health risks, as well documented in the relevant literature, but also to the perceived risks. These findings document the global impact of the COVID-19 crisis as well as provide guidance for transportation practitioners in developing future strategies.


Assuntos
COVID-19/epidemiologia , Pandemias , Meios de Transporte , Humanos , Análise de Regressão , Fatores de Risco , Inquéritos e Questionários , Viagem
13.
Materials (Basel) ; 14(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375189

RESUMO

Improving the self-healing performance of asphalt by employing encapsulation technology is a topic of wide interest. This study investigated the performance of sunflower oil, engine oil, and waste cooking oil based on the microhealing mechanism of asphalt with compartmented polymeric fiber. Capillary flow, contact angle, Brookfield viscosity, bar thin layer chromatography, and fatigue-recovery-fatigue tests were conducted to characterize the capillary flow capacity, wetting ability, viscosity reduction ability, suitability of components, and performance restoration ability of the different kinds of healing agents. The diffusion process of sunflower oil in asphalt was simulated using molecular dynamics. The results showed that sunflower oil exhibited the best capillary flow capacity, viscosity reduction ability, and the fastest wetting rate in asphalt. Engine oil exhibited the largest wetting work and the best recovery performance related to fatigue. The diffusion process of sunflower oil in asphalt could be divided into two stages. Two major factors (aging and higher temperature) increased the diffusion rate of sunflower oil in asphalt. The comprehensive analysis showed that sunflower oil was the most suitable to be encapsulated to improve the self-healing performance of asphalt.

14.
Data Brief ; 33: 106459, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33163599

RESUMO

COVID-19 pandemic has heavily impacted the global community. To curb the viral transmission, travel restrictions have been enforced across the world. The dataset documents the mobility disruptions and the modal shifts that have occurred as a consequence of the restrictive measures implemented in ten countries: Australia, Brazil, China, Ghana, India, Iran, Italy, Norway, South Africa and the United States. An online questionnaire was distributed during the period from the 11st to the 31st of May 2020, with a total of 9 394 respondents. The first part of the survey has characterized the frequency of use of all transport modes before and during the enforcement of the restrictions, while the second part of the survey has dealt with perceived risks of contracting COVID-19 from different transport modes and perceived effectiveness of travel mitigation measures. Overall, the dataset (stored in a repository publicly available) can be conveniently used to quantify and understand the modal shifts and people's cognitive behavior towards travel due to COVID-19. The collected responses can be further analysed by considering other demographic and socioeconomic covariates.

15.
Data Brief ; 32: 106169, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32835042

RESUMO

The dataset deals with the air quality perceived by citizens before and during the enforcement of COVID-19 restrictions in ten countries around the world: Australia, Brazil, China, Ghana, India, Iran, Italy, Norway, South Africa and the United States. An online survey conveniently translated into Chinese, English, Italian, Norwegian, Persian, Portuguese collected information regarding the perceived quality of air pollution according to a Likert scale. The questionnaire was distributed between 11-05-2020 and 31-05-2020 and 9 394 respondents took part. Both the survey and the dataset (stored in a Microsoft Excel Worksheet) are available in a public repository. The collected data offer the people's subjective perspectives related to the objective improvement in air quality occurred during the COVID-19 restrictions. Furthermore, the dataset can be used for research studies involving the reduction in air pollution as experienced, to a different extent, by populations of all the ten countries.

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