Universidade Federal do Rio Grande (FURG)
Recent publications
Introdução / objetivo: Esta pesquisa foi realizada com o objetivo de demonstrar os fatores que impactam a aceitação de tecnologia de armazenamento em nuvem nos escritórios de contabilidade filiados a uma instituição representativa de seus interesses no estado do Rio Grande do Sul, Brasil, amparada pelos paradigmas propostos pela Teoria Unificada de Aceitação e Uso de Tecnologia. Metodologia: A coleta de dados procedeu-se por meio de um questionário disponibilizado aos endereços eletrônicos dos responsáveis pelos escritórios de contabilidade, por meio do sistema Google Form. Na análise dos dados, o estudo recorreu ao software SPSS 25, para a apresentação da estatística descritiva, e ao software SmartPLS 3.0, para a modelagem de equações estruturais. Resultados: As evidências da pesquisa apontaram que apenas a variável “hábito” apresentou significância, demonstrando que somente esse construto apresenta influência significativa na intenção de uso da ferramenta de armazenamento em nuvem. Conclusões: Como contribuição, este estudo auxilia na gestão organizacional, no entendimento dos fatores influenciadores da adoção de tecnologias de armazenamento em nuvem, a fim de melhorar a rotina dos escritórios de contabilidade e maximizar a agilidade, o custo e a segurança do armazenamento de dados. Introduction / objective: This research was carried out to demonstrate the factors that impact the acceptance of cloud storage technology in accounting offices affiliated with an institution representing their interests in the state of Rio Grande do Sul, supported by the paradigms proposed by the Unified Theory of Acceptance and Use of Technology. Methodology: Data collection was carried out through a questionnaire made available to the electronic addresses of those responsable for accounting offices, through the Google Form system. In data analysis, the study used the SPSS 25 software for the presentation of descriptive statistics and the SmartPLS 3.0 software for structural equation modeling (SEM) Results: The research evidence showed that only the variable habit presented a positive hypothesis, demonstrating that only this construct has a significant influence on the intention to use the cloud storage tool. Conclusions: As a contribution, this study helps organizational management in understanding the factors influencing the adoption of cloud storage technologies, aiming to improve the routine of accounting offices and maximize the agility, cost, and security of data storage.
Morphological, morphometric, and chemical analysis of otoliths have proven to be useful tools for intraspecific comparison and identification of fish stocks. In the present study, we used otolith silhouette and morphometric analysis (n = 103) in addition to chemical signatures (n = 20) to test the hypothesis of a single stock unit of skipjack tuna (Katsuwonus pelamis) in the Southwest Atlantic Ocean (20–34°S). No significant differences were found between sexes (t-test p > 0.05), enabling analyses for all study specimens to be grouped. Cluster analysis using Fourier coefficients (30 first harmonics) differentiated three otolith morphotypes within South (28–34°S) and Southeast (20–28°S) regions of the study area. Harmonic principal component analysis using the first two significant axes showed no pattern of spatial separation by region. Among the seven shape descriptors examined, only circularity and form factor showed significant differences between the morphotypes (A and B). Microchemistry analysis (LA/ICP-MS) applied to the core portion of fish otoliths showed significant differences in Ba, Mn and Mg concentrations between the two regions and morphotypes (p < 0.05). These results support that the Katsuwonus pelamis population in the Southwest Atlantic Ocean belong to a single stock unit with a probable common area of origin. Specimens captured in the South and Southeast regions of Brazil had heterogeneous phenotypic attributes regarding otolith shape, probably determined by a temporal equilibrium selection process.
O presente trabalho teve como objetivo a determinação das propriedades de dureza, obtidas na liga ASTM 7075, submetida aos tratamentos de solubilização e envelhecimento artificial, com as temperaturas de envelhecimento em 150 °C e 180 °C. O aumento da temperatura visa à redução de tempos de tratamento menores do que os convencionais, permitindo uma maior produção de componentes, a partir desse tratamento. As amostras foram submetidas aos tratamentos térmicos e caracterizadas, antes e depois de cada tratamento, por análise microestrutural, ensaio de dureza e difratometria de raios-X. As amostras envelhecidas artificialmente a 180 °C têm dureza menor do que as envelhecidas a 150 °C. Isso evidencia a importância da distribuição dos precipitados de forma dispersa, contribuindo, mais efetivamente, com as propriedades mecânicas obtidas. Os tempos de envelhecimento, utilizados no estudo, foram de 2, 4, 6 e 8 horas. Esses períodos foram suficientes para atingir o pico de dureza nas curvas de envelhecimento, e as máximas durezas obtidas são compatíveis com as encontradas em outros estudos com esse material. Palavras-chave: ASTM 7075; tratamentos térmicos; envelhecimento.
Rio Grande is a medium-sized industrial city located in the extreme south of Brazil and previous studies in this city have shown contamination by metal(loids) and polycyclic aromatic hydrocarbons (PAHs) in water, soil, sediment and in the atmosphere. In Brazil, the incorporation of PM2.5 monitoring in environmental legislation is recent (2018) and, like other developing countries, the number of studies is still small. This study aimed to investigate the levels of PM2.5 in the industrial and urban area of Rio Grande, to determine the concentration of metal(loid)s As, Cd, Cu and Pb and of 16 PAHs in the samples of PM2.5, to perform the health risk assessment for these contaminants and the health impact assessment for two possible scenarios of reduction of PM2.5 levels. Our main findings regarding the PM2.5 samples include: (1) The levels of this pollutant in the city of Rio Grande were higher than allowed in current Brazilian legislation, both in the industrial and urban areas; (2) existence of non-carcinogenic and carcinogenic risk for metals present in all samples; (3) absence of carcinogenic risk for the assessed PAHs; and (4) the reduction scenarios proposed pointed to a reduction of up to 22 deaths annually in conjunction with reductions in health-related expenditures. Thus, these results may serve as a basis for the development of public health policies aimed at improving air quality, jointly assisting health surveillance and directing future studies towards a better intrinsic approach to the problem.
Objectives: To describe the use of dental services in two periods and associated factors in older people residing in the rural area of a municipality in southern Brazil. Methods: This was a cross-sectional study nested in a cohort study. A standardised questionnaire was used to collect the variables of interest. The dependent variables were the use of dental services in the 12 and 36 months prior to the interview. Results: A total of 863 older people were interviewed, 24.7% of whom had visited a dentist in the previous year and 38.7% had visited a dentist in the previous 3 years. Skin colour, health insurance and self-rated health were associated with both outcomes. Individuals with non-white skin, those who did not have health insurance and those who considered their health to be poor or very poor were more likely to take a long time before seeking oral health services. Differences between the two outcomes were observed in oral health and the use of tobacco. The likelihood of having gone more than 3 years without visiting a dentist was greater among smokers and lower among those with dental caries. Conclusions: The prevalence of dental service use was low. Variables related to the adoption of unhealthy behaviours and the occurrence of oral diseases were only related to the use of dental services 36 months prior to the interview. Public policies must be reorganised to prioritise population groups with greater difficulties in the use of dental services.
We performed an unprecedented investigation of the seasonal variability in carbonate system parameters (the total alkalinity – AT, the total dissolved inorganic carbon – CT, the pH, and the partial pressure of carbon dioxide – pCO2) in the lower zone of the Patos Lagoon Estuary (PLE), the largest choked lagoon in the world. Sampling was conducted monthly from May 2017 to June 2021. AT and pH were measured during the study period, while other carbonate system parameters were estimated using CO2Sys software. The pH distribution reflected the average natural alkaline conditions throughout the year, with an average of 8.0 pH units. The surface waters in the lower zone of the PLE are generally characterized by a supersaturated calcium carbonate environment. However, a susceptibility to undersaturation conditions was observed during winter (calcite and aragonite) and spring (aragonite). Furthermore, the average surface water pCO2 was 394 μatm during the analyzed period, with the highest values recorded in winter and early spring. The predominant estuarine processes governing changes in the carbonate system in the PLE were the dilution and concentration of salts. These processes depend on the complex balance between freshwater outflows and oceanic inflows that change the surface salinity and produce favorable conditions for primary producer development and the input of continental carbon. However, the remineralization of organic matter and CO2 ingassing likely contribute to the deviations in the theoretical mixing line, causing the increased CT in the region. In addition, the nonthermal effects on seasonal changes in the pCO2 prevail over thermal effects, and the region presents an ocean-dominated (riverine-dominated) condition during summer and autumn (winter and spring). The novel results described here reveal the complexity and challenges that still exist to a better comprehension of how carbonate system parameters evolve temporally and spatially in the PLE, especially considering the climate- and anthropogenic-driven stressors. Finally, this study contributes to the understanding of carbonate system variability in coastal ecosystems and highlights the need for more intense and continuous biogeochemical monitoring of Southern Hemisphere estuaries.
Feather is the most abundant keratinous material in nature. This by-product of animal origin has about 80–90% of crude protein. This work aimed to maximize the enzymatic hydrolysis of feather meal using the proteolytic enzyme from Bacillus sp. P45 and evaluate the antioxidant capacity of different fractions of the hydrolysate. Enzymatic hydrolysis was maximized using a central composite rotatable design (CCRD) 2⁴, where the effects of the variables CaCl2 concentration (0–100 mmol/L), temperature (35–55 °C), enzyme/substrate ratio (600–6000 U/g-protein), and substrate protein concentration (10–40 g/L) were estimated on the responses degree of hydrolysis (DH) and protein recovery (PR). The highest values of DH and PR were obtained when the hydrolysis was performed with 50 mmol/L of CaCl2, 50 °C, 6000 U/g-protein, and substrate protein concentration of 10 g/L. Hydrolysate presented DH of 8.4% and PR of 37.5% at 6 h of reaction. The obtained peptides were separated by molecular weight through a sequential ultrafiltration process in the membranes of 10 and 3 kDa, and the antioxidant activities of the different fractions were analyzed. The fraction < 3 kDa showed a higher capacity to sequester radicals ABTS⋅+ (90.20 μmol TE/g) and peroxyl (1892.47 μmol TE/g). This study shows the potential of Bacillus sp. P45 in hydrolyzing feather meal, resulting in peptides with antioxidant activity. Graphical Abstract
Short waves growth is characterized by nonlinear and dynamic processes that couple ocean and atmosphere. Ocean surface currents can have a strong impact on short wave steepness and breaking, modifying the surface roughness, and consequently their growth. However, this interplay is poorly understood and observations are scarce. This work uses in situ measurements of near-surface winds, surface current, and waves under strong tidal current conditions to investigate the relative wind speed effect on the local short waves growth. Those observations were extensive compared with numerical modeling using WAVEWACHIII, where the simulations repeatedly fail to reproduce the observed wind sea energy under strong current conditions. Our field observations and coupled ocean-atmosphere numerical simulations suggest that surface currents can strongly modulate surface winds. That is a local process, better observed closer to the boundary layer than at 10 m height. Yet, it can cause a significant impact on the local wind shear estimation and consequently on the local waves’ growth source term. The results presented here show that the relative wind effect is not well solved inside spectral waves models, causing a significant bias around the peak of wind sea energy.
Since the publication of two phase III clinical trials not supporting the use of progesterone in patients with traumatic brain injury (TBI), several possible explanations have been postulated, including limitations in the analysis of results from preclinical evidence. Therefore, to address this question, a systematic review and meta-analysis was performed to evaluate the effects of progesterone as a neuroprotective agent in preclinical animal models of TBI. A total of 48 studies were included for review: 29 evaluated brain edema, 21 evaluated lesion size, and 0 studies reported the survival rate. In the meta-analysis, it was found that progesterone reduced brain edema (effect size − 1.73 [− 2.02, − 1.44], p < 0.0001) and lesion volume (effect size − 0.40 [− 0.65, − 0.14], p = 0.002). Lack of details in the studies hindered the assessment of risk of bias (through the SYRCLE tool). A funnel plot asymmetry was detected, suggesting a possible publication bias. In conclusion, preclinical studies show that progesterone has an anti-edema effect in animal models of TBI, decreasing lesion volume or increasing remaining tissue. However, more studies are needed using assessing methods with lower risk of histological artifacts.
Numerous studies have evaluated the effects of lockdowns during the COVID-19 pandemic, but most of them have concerned large cities and regions. This study aimed to evaluate the dynamics of air pollutants during and after the implementation of a short lockdown in the medium-sized city of Pelotas, Brazil, using hourly measurements of pollutants. The evaluation period included in this study was between August 9 th and 12 th , 2020. A machine learning model was used to investigate the expected behavior against what was observed during the study period. All pollutants presented a gradual reduction until a dynamic plateau established 48 hours after the start of the lockdown: NO 2 (↓4%), O 3 (↓34%), SO 2 (↓24%), CO (↓48%), PM 10 (↓82%) and PM 2.5 (↓82%). At the end of the restriction measures, the PM 10 and PM 2.5 levels continued to decline beyond expectations. Our findings show that these measures can positively affect the air quality in medium-sized cities. ARTICLE HISTORY
Ozone (O3 ) represents a great threat to human health, contributing to respiratory diseases and premature mortality. This pollutant is often considered a critical pollutant in regions of southern Brazil. Exposure to this pollutant during vigorous physical activity should be the subject of thorough investigations due to the increased ventilation rate and altered breathing pattern present during vigorous physical activity that result in greater inhalation of O3 . Thus, this study aimed to evaluate the health risk of exposure to low, mean, and high concentrations of O 3 during different durations of exercise in the city of Rio Grande (southern Brazil). Healthy young men (n=45) performed cardiopulmonary exercise testing, and ventilation rate data were collected to predict total ventilation and pollutant inhalation during a 5 km running session. The O3 concentration in the city of Rio Grande was measured using the Copernicus Atmosphere Monitoring Service (CAMS). The environmental health risk was calculated based on the potential intake dose. The lowest, mean, and highest concentrations of O3 detected during the monitoring period were 32.5 µg/m3 , 64.9 µg/m3 , and 115.2 µg/m3 , respectively. In all evaluated scenarios, there was a toxicological risk (RQ> 1), except when exercising when the O 3 concentration was lowest for the shortest length of time (p<0.001). As the concentration of O3 and the duration of the exposure increase, the health risk is increased. Therefore, O3 concentration and duration of exposure are factors influencing the health risk of exercising. These findings are extremely relevant in cities that have high levels of O3 , such as the city of Rio Grande.
The aim of this study was to evaluate the theoretical potential of methane production of the food waste generated by a university restaurant, as well as to verify the influence of the fruit and vegetable waste in the feeding composition of an anaerobic bioreactor treating this type of waste. Four feeding compositions combining three fractions of the food waste (fruit and vegetable fraction, soy protein and beans fraction, and rice fraction) at different concentrations were tested in anaerobic processes lasting 10 and 30 days. Additionally, a study of the theoretical potential of methane production from each fraction that composes the food waste was carried out, as well as the evaluation of the specific methanogenic activity of the anaerobic sludge. Despite its low theoretical potential of methane production (0.037 LCH4/g), the presence of the fruit and vegetable mixture in three of the feeding compositions led to greater organic matter degradation (above 69%) and CH4 yields (above 0.20 LCH4/gVS) in both periods tested, in comparison with the achieved by the feeding composition lacking this fraction. The results suggest that the presence of the fruit and vegetable mixture contributed with the supplementation of micro- and macroelements to the anaerobic sludge during the digestion of food waste.
The aim of the present study was to evaluate the anti-glioma activity of 3-(4-fluorobenzyl)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione (AV23) in a preclinical model of glioblastoma, as well as behavioral parameters and toxicological profile. The implantation of C6 cells in the left striatum of male Wistar rats was performed by stereotaxic surgery. After recovery, animals were treated with vehicle (canola oil) or AV23 (10 mg/kg/day) intragastrically for 15 days. It was found that AV23 reduced tumor volume by 90%. Serum biochemical parameters such as triglycerides, cholesterol, HDL-cholesterol, LDL-cholesterol, albumin, aspartate aminotransferase, urea, creatinine and total proteins were not changed; however, there was a slight increase in alanine aminotransferase. The compound AV23 reverted the hypoglycemia and the reduction in body weight caused by glioblastoma. Additionally, AV23 was able to revert the reduction of locomotion caused by the tumor implantation. Therefore, the compound AV23 can be considered a promising candidate in the treatment of glioblastoma.
This study aimed to describe changes in cesarean section (C-section) prevalence from 2007 to 2019, in public and private sectors, according to maternal characteristics. We included all puerperal women who gave birth in Rio Grande, Rio Grande do Sul, Brazil, at years 2007, 2010, 2013, 2016 and 2019. A questionnaire was applied up to 48 hours after delivery. We assessed C-section rates over time and described the prevalence according to independent variables. Poisson regression was used. A total of 12.415 puerperal women were included. The prevalence of C-section increased between 2007-2013 (from 51.2% to 61.2%) and decreased between 2013-2019 (48.9% in 2019). This decrease was observed only in the public sector and was higher among the youngest (-10.0 percentual points) and high educated women (-10.3 percentual points). While in the private sector C section occurrence increased even more (95.7% in 2019). In the public sector, women that were older, with a partner, primiparous, who performed prenatal care in the private system and with adequate prenatal assistance presented higher prevalence of C-section. In the private sector the prevalence was high independently of the maternal characteristics. In order to reduce C-section rates, efficient delivery care policies mainly focused on the private sector are necessary.
Arsenic (As) is a soil contaminant with important interactions with the soil microbial community. Upon contamination, soil microbes can display metabolic changes, which can be measured through the profiling of their potential for the oxidation of organic substrates. The present study aimed to evaluate the microbial metabolic profile in soil samples containing different forms of inorganic As (AsIII and AsV) in a 360-day experiment. Soil samples were contaminated with AsIII or AsV (15 mg/kg soil) and the microbial metabolic profile was evaluated after 3, 30, 180, and 360 days of experiment. After these periods, the assay was performed using Biolog Ecoplate™ microplates followed by incubation with readings every 24 h for 5 days. The main parameters evaluated were metabolic activity (AWCD), diversity (Shannon index), and use of substrates containing N or P (NUSE and PUSE). It was observed that the microbial community reacted differently according to the exposure time and for the two contaminants. While metabolic activity decreased in the AsV group (p = 0.03) in 30 days when compared to the control group, the use of sources containing nitrogen decreased in the AsIII group (p = 0.01) only after 360 days when compared to the control group. These findings indicate that the soil microbial community suffers a decrease in metabolic activity when exposed to arsenate in short exposures, whereas, in soil with long-term exposure to arsenite, the microbial community suffers a decrease in the consumption of nitrogen-rich substrates.
The life history and population dynamics of the marine demersal bony fish Percophis brasiliensis were studied to assess its stock status in southern Brazil. Specimens were sampled from commercial landings, and the length, weight, sex, and maturity stage were recorded from each individual. Sagittal otoliths were removed for aging, and the gonads were weighed for maturity studies. Size compositions were also evaluated from commercial landings of different fishing fleets. The analysis of edge type validated the aging data. The oldest and largest individuals were 12 years and 718 mm in total length, respectively. Growth parameters fitted to the von Bertalanffy model were L∞=625.0mm, k 0.39 year⁻¹, t0=−0.26 years for females, L∞=573.4mm, k = 0.34 year⁻¹, t0 = −1.13 for males and L∞=617.6mm, k = 0.33 year⁻¹t0 = −0.82 for both sexes. The length and age at first maturity of females were 407.7 mm and 2.2 years, respectively. The reproductive season was estimated to occur during spring from September to December, with a peak in October. The life history parameters and the reproductive season described in this study are similar to those estimated by other studies on southern stocks fished in Uruguayan and Argentinian waters. The estimated population trends presented a steady decrease between 1986 and 2005, a slight increase from 2005 and 2010, and a sharp decline until 2019. The stock status was estimated as overfished but not suffering overfishing. Despite not being a target species, the biomass decline trajectory of Percophis brasiliensis reflects intense targeting of other bottom trawl species in the same depth range. These results highlight the importance of life-history studies and continuous monitoring of species impacted by fisheries. Their depletion may affect the functional relationships in marine ecosystems and threaten the resilience of populations to stochastic effects such as climatic variations.
The western Tropical Atlantic Ocean is a biogeochemically complex region due to the structure of the surface current system and the large freshwater input from the Amazon River coupled with the dynamics of precipitation. Such features make it difficult to understand the dynamics of the carbon cycle, leading to contrasting estimates in sea-air CO2 exchanges in this region. Here we demonstrate that these contrasting estimates occur because the western Tropical Atlantic Ocean can be split into three distinct sub-regions in terms of the sea-air CO2 exchanges. The sub-region under the North Brazil Current domain acts as a weak annual CO2 source to the atmosphere, with low interannual variability. The sub-region under the North Equatorial Current influence acts as an annual CO2 sink, with great temporal variability. The third sub-region under the Amazon River plume influence shows greater interannual variability of CO2 exchanges, but it always acts as a net oceanic sink for CO2. Despite this large spatial variability, the entire region acts as a net annual CO2 sink of –1.6 ± 1.0 mmol m–2 day–1. Importantly, the Amazon River plume waters drive 87% of the CO2 uptake in the western Tropical Atlantic Ocean. In addition, we found a significant increasing trend in sea surface CO2 partial pressure in the North Brazil Current and North Equatorial Current waters. Such trends are more pronounced than the increase in atmospheric CO2 partial pressure, revealing the sensitivity of carbon dynamics in these sub-regions to global climate change.
According to the literature, educational technologies present several learning benefits to promote online education. However, there are several associated challenges, and some studies illustrate the limitations in elaborating educational technologies, called Design limitations. This aspect is responsible for unleashing various issues in the learning process, such as gender inequality, creating adverse effects on cognitive, motivational, and behavioral mediators, which opposes the fifth UN’s Sustainable Development Goal. Therefore, many studies notice the harmful effects of stereotypes in educational technologies. These effects can be included in the design, like colors or other stereotyped elements, or how the activity is conducted. Based on this, the present study aimed to verify the predominance of color bias in educational technologies available on the WEB. This study developed a computational solution to calculate male and female color bias in the available educational technology web pages. The results suggest the prevalence of the development of educational technologies with a male color bias, with an imbalance among genders, without adequate customization for age groups. Furthermore, some environments, such as Computer Science, present a higher color bias for men when compared to women. Despite both scales being independent, results indicated interesting evidence of a substantial prevalence of colors associated with the male scale. According to the literature, this may be associated with dropout and lack of interest in female students, especially in sciences, technology, engineering, and mathematics domains.
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Pedro Silva
  • Faculty of Medicine - Famed
Silvina Botta
  • Institute of Oceanography - IO
Erik Muxagata
  • Institute of Oceanography - IO
Marta Regina Cezar-Vaz
  • School of Nursing - EEnf
Av. Itália km 8 Bairro Carreiros, 96203-900, Rio Grande, RS, Brazil