RESUMEN
Exposure to ambient ozone (O3) is linked to increased mortality risks from various diseases, but epidemiological investigations delving into its potential implications for cancer mortality are limited. We aimed to examine the association between short-term O3 exposure and site-specific cancer mortality and investigate vulnerable subgroups in Brazil. In total 3,459,826 cancer death records from 5570 Brazilian municipalities between 2000 and 2019, were included. Municipal average daily O3 concentration was calculated from a global estimation at 0.25°×0.25° spatial resolution. The time-stratified case-crossover design was applied to assess the O3-cancer mortality association. Subgroup analyses by age, sex, season, time-period, region, urban hierarchy, climate classification, quantiles of GDP per capita and illiteracy rates were performed. A linear and non-threshold exposure-response relationship was observed for short-term exposure to O3 with cancer mortality, with a 1.00% (95% CI: 0.79%-1.20%) increase in all-cancer mortality risks for each 10-µg/m3 increment of three-day average O3. Kidney cancer was most strongly with O3 exposure, followed by cancers of the prostate, stomach, breast, lymphoma, brain and lung. The associated cancer risks were relatively higher in the warm season and in southern Brazil, with a decreasing trend over time. When restricting O3 concentration to the national minimum value during 2000-2019, a total of 147,074 (116,690-177,451) cancer deaths could be avoided in Brazil, which included 17,836 (7014-28,653) lung cancer deaths. Notably, these associations persisted despite observed adaptation within the Brazilian population, highlighting the need for a focus on incorporating specific measures to mitigate O3 exposure into cancer care recommendations.
RESUMEN
BACKGROUND: Low temperatures are adverse contributors to cardiovascular diseases, but the associations between short-term exposure to cold and the risk of death from aortic dissection and aneurysm remain unclear, particularly in tropical regions. OBJECTIVE: This study was conducted based on 123,951 records of deaths caused by aortic dissection and aneurysms extracted from the national Mortality Information System in Brazil between 2000 and 2019. METHODS: Relative risks and 95 % confidence intervals (CI) for the aortic-related deaths associated with low ambient temperatures were estimated using the conditional logistic model combined with the distributed lag nonlinear model. Subgroup analyses were performed by age group, sex, race, education level, and residential region. Furthermore, this study calculated the number and fraction of aortic-related deaths attributed to temperatures below the temperature threshold to quantify the cold-related mortality burden of aortic diseases. RESULTS: During the study period, aortic-related deaths and mortality rates in Brazil exhibited a steady increase, rising from 4419 (2.66/100,000) in 2000 to 8152 (3.88/100,000) in 2019. Under the identified temperature threshold (26 °C), per 1 °C decrease in daily mean temperature was associated with a 4.77 % (95 % CI: 4.35, 5.19) increase in mortality risk of aortic-related diseases over lag 0-3 days. Females, individuals aged 50 years or older, Asian and Black race, and northern residents were more susceptible to low temperatures. Low temperatures were responsible for 19.10 % (95 % CI: 17.71, 20.45) of aortic-related deaths in Brazil. CONCLUSION: This study highlights that low temperatures were associated with an increased risk of aortic-related deaths, with a remarkable burden even in this predominantly tropical country.
Asunto(s)
Aneurisma de la Aorta , Disección Aórtica , Frío , Humanos , Brasil/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Disección Aórtica/mortalidad , Anciano , Aneurisma de la Aorta/mortalidad , Frío/efectos adversos , Adulto , Clima Tropical , Adulto Joven , Anciano de 80 o más Años , Factores de Riesgo , AdolescenteRESUMEN
Random matrix theory, particularly using matrices akin to the Wishart ensemble, has proven successful in elucidating the thermodynamic characteristics of critical behavior in spin systems across varying interaction ranges. This paper explores the applicability of such methods in investigating critical phenomena and the crossover to tricritical points within the Blume-Capel model. Through an analysis of eigenvalue mean, dispersion, and extrema statistics, we demonstrate the efficacy of these spectral techniques in characterizing critical points in both two and three dimensions. Crucially, we propose a significant modification to this spectral approach, which emerges as a versatile tool for studying critical phenomena. Unlike traditional methods that eschew diagonalization, our method excels in handling short timescales and small system sizes, widening the scope of inquiry into critical behavior.
RESUMEN
Although some studies have found that short-term PM2.5 exposure is associated with lung cancer deaths, its impact on other cancer sites is unclear. To answer this research question, this time-stratified case-crossover study used individual cancer death data between January 1, 2000, and December 31, 2019, extracted from the Brazilian mortality information system to quantify the associations between short-term PM2.5 exposure and cancer mortality from 25 common cancer sites. Daily PM2.5 concentration was aggregated at the municipality level as the key exposure. The study included a total of 34,516,120 individual death records, with the national daily mean PM2.5 exposure 15.3 (SD 4.3) µg/m3. For every 10-µg/m3 increase in three-day average PM2.5 exposure, the odds ratio (OR) for all-cancer mortality was 1.04 (95% CI 1.03-1.04). Apart from all-cancer deaths, PM2.5 exposure may impact cancers of oesophagus (1.04, 1.00-1.08), stomach (1.05, 1.02-1.08), colon-rectum (1.04, 1.01-1.06), lung (1.04, 1.02-1.06), breast (1.03, 1.00-1.06), prostate (1.07, 1.04-1.10), and leukaemia (1.05, 1.01-1.09). During the study period, acute PM2.5 exposure contributed to an estimated 1,917,994 cancer deaths, ranging from 0 to 6,054 cases in each municipality. Though there has been a consistent downward trend in PM2.5-related all-cancer mortality risks from 2000 to 2019, the impact remains significant, indicating the continued importance of cancer patients avoiding PM2.5 exposure. This nationwide study revealed a notable association between acute PM2.5 exposure and heightened overall and site-specific cancer mortality for the first time to our best knowledge. The findings suggest the importance of considering strategies to minimize such exposure in cancer care guidelines. ENVIRONMENTAL IMPLICATION: The 20-year analysis of nationwide death records in Brazil revealed that heightened short-term exposure to PM2.5 is associated with increased cancer mortality at various sites, although this association has gradually decreased over time. Despite the declining impact, the research highlights the persistent adverse effects of PM2.5 on cancer mortality, emphasizing the importance of continued research and preventive measures to address the ongoing public health challenges posed by air pollution.
Asunto(s)
Contaminantes Atmosféricos , Exposición a Riesgos Ambientales , Neoplasias , Material Particulado , Humanos , Material Particulado/toxicidad , Material Particulado/análisis , Brasil/epidemiología , Neoplasias/mortalidad , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/efectos adversos , Masculino , Femenino , Estudios Cruzados , Persona de Mediana Edad , Anciano , AdultoRESUMEN
INTRODUCTION: The prevalence of neurological disorders is high among the Mexican population. Clonazepam is primarily indicated to treat panic disorders, certain kinds of epilepsy such as status epilepticus, childhood motor seizures (petit mal absence, Lennox-Gastaut syndrome, and infantile spasms), anxiety, and muscle spasm. This study was performed to compare bioequivalence between two oral tablet formulations of clonazepam 2 mg in healthy Mexican volunteers under fasting conditions. METHODS: This phase I, randomized, open-label, two-treatment, crossover study included 30 healthy volunteers. Subjects were randomly assigned to either test or reference formulation of clonazepam 2 mg. Each study period was separated by 21-day washout period. Blood samples were collected at pre-dose and up to 72 h after drug administration. Clonazepam concentrations were determined using a validated ultra-flow liquid chromatography-tandem mass spectrometric method. Pharmacokinetic parameters were determined using a non-compartmental method. Two formulations were considered bioequivalent if geometric mean ratios (test/reference) were between 80% and 125%. Safety was evaluated by recording adverse events. RESULTS: Pharmacokinetic parameters were comparable between test and reference formulations. The mean maximum plasma concentration (Cmax) was ≈ 13 ng/mL, area under the plasma concentration-time curve from time 0 to last measurable concentration (AUC0-t) was ≈ 360 ng h/mL, time to reach maximum plasma concentration (Tmax) was ≈ 3 h, and elimination half-life (t1/2) was ≈ 43 h. Geometric mean ratios (90% confidence interval) of Cmax (99.2-115.3%), AUC0-t (100.6-110.6%), and AUC0-∞ (98.5-111.6%) were within the bioequivalence range. Seven non-serious adverse events (mostly asymptomatic hypotension) were recorded. CONCLUSION: The test and reference formulations of clonazepam 2 mg were bioequivalent and well tolerated in healthy Mexican volunteers under fasting conditions. PROTOCOL AUTHORIZATION NUMBER: 213301410B0051 (Approved on April 13, 2021).
RESUMEN
Background: Fatigue is associated with increased injury risk along with changes in balance control and task performance. Musculoskeletal injury rates in runners are high and often result from an inability to adapt to the demands of exercise and a breakdown in the interaction among different biological systems. This study aimed to investigate whether changes in balance dynamics during a single-leg squat task following a high-intensity run could distinguish groups of recreational runners who did and did not sustain a running-related injury within 6 months. Methods: Thirty-one healthy recreational runners completed 60 s of single-leg squat before and after a high-intensity run. Six months after the assessment, this cohort was separated into two groups of 13 matched individuals with one group reporting injury within this period and the other not. Task performance was assessed by the number of repetitions, cycle time, amplitude, and speed. To evaluate balance dynamics, the regularity and temporal correlation structure of the center of mass (CoM) displacements in the transverse plane was analyzed. The interaction between groups (injury, non-injured) and time (pre, post) was assessed through a two-way ANOVA. Additionally, a one-way ANOVA investigated the percent change difference of each group across time. Results: The injured group presented more regular (reduced entropy; 15.6%) and diffusive (increased short-term persistence correlation; 5.6%) CoM displacements after a high-intensity run. No changes were observed in the non-injured group. The within-subject percent change was more sensitive in demonstrating the effects of fatigue and distinguishing the groups, compared to group absolute values. No differences were observed in task performance. Discussion: Runners who were injured in the future demonstrate changes in balance dynamics compared to runners who remain injury-free after fatigue. The single-leg squat test adopted appears to be a potential screening protocol that provides valuable information about balance dynamics for identifying a diminished ability to respond to training and exercise.
RESUMEN
BACKGROUND: Often marginalized and disadvantaged by systems of oppression, Indigenous populations commonly face significant barriers to accessing adequate antenatal care (ANC). The COVID-19 pandemic had an unprecedented impact on healthcare systems worldwide, including on the provision of antenatal care; this was especially so for Indigenous communities in many regions. As such, our study aimed to estimate the association between the COVID-19 pandemic and adequate ANC received by Indigenous women in Chiapas, Mexico. METHODS: We conducted a retrospective crossover analysis with data collected between June and December 2021 from Indigenous women who attended at least one ANC appointment at one of two health centers in San Cristóbal de las Casas, Chiapas. We used a multinomial logistic regression model considering the time frame (before and during the pandemic) as the primary independent variable. Adequate antenatal care comprised four dimensions: attendance by qualified personnel, timely first visit, sufficient frequency of visits, and adequacy of the content provided during the visits. RESULTS: During the COVID-19 pandemic, there was a significant drop in ANC adequacy, with 12.7% (95% CI: 8.3, 18.9) of Indigenous women receiving ANC, compared with the pre-pandemic rate of 52.5% (95% CI: 44.7, 60.3), among the 158 participants. The pandemic resulted in a reduction of 75.8% in the adequacy of ANC. Considering the four dimensions of adequacy, we found that having only one dimension was associated with a relative risk ratio (RRR) of 12.45 (95% CI: 6.40, 24.23), while having two or three dimensions was associated with a RRR of 5.23 (95% CI: 2.83, 9.65) when using adequate ANC as the category of reference. CONCLUSIONS: According to our results, Indigenous women's ANC adequacy was negatively affected by the COVID-19 pandemic. In light of these findings, we emphasize the importance of developing healthcare systems that are prepared to adapt consultation schemes by implementing virtual visits and incorporating community health workers.
RESUMEN
The restricted Boltzmann machine (RBM) is a generative neural network that can learn in an unsupervised way. This machine has been proven to help understand complex systems, using its ability to generate samples of the system with the same observed distribution. In this work, an Ising system is simulated, creating configurations via Monte Carlo sampling and then using them to train RBMs at different temperatures. Then, 1. the ability of the machine to reconstruct system configurations and 2. its ability to be used as a detector of configurations at specific temperatures are evaluated. The results indicate that the RBM reconstructs configurations following a distribution similar to the original one, but only when the system is in a disordered phase. In an ordered phase, the RBM faces levels of irreproducibility of the configurations in the presence of bimodality, even when the physical observables agree with the theoretical ones. On the other hand, independent of the phase of the system, the information embodied in the neural network weights is sufficient to discriminate whether the configurations come from a given temperature well. The learned representations of the RBM can discriminate system configurations at different temperatures, promising interesting applications in real systems that could help recognize crossover phenomena.
RESUMEN
BACKGROUND: Satellite-based PM2.5 predictions are being used to advance exposure science and air-pollution epidemiology in developed countries; including emerging evidence about the impacts of PM2.5 on acute health outcomes beyond the cardiovascular and respiratory systems, and the potential modifying effects from individual-level factors in these associations. Research on these topics is lacking in low and middle income countries. We aimed to explore the association between short-term exposure to PM2.5 with broad-category and cause-specific mortality outcomes in the Mexico City Metropolitan Area (MCMA), and potential effect modification by age, sex, and SES characteristics in such associations. METHODS: We used a time-stratified case-crossover study design with 1,479,950 non-accidental deaths from the MCMA for the period of 2004-2019. Daily 1 × 1 km PM2.5 (median = 23.4 µg/m3; IQR = 13.6 µg/m3) estimates from our satellite-based regional model were employed for exposure assessment at the sub-municipality level. Associations between PM2.5 with broad-category (organ-system) and cause-specific mortality outcomes were estimated with distributed lag conditional logistic models. We also fit models stratifying by potential individual-level effect modifiers including; age, sex, and individual SES-related characteristics namely: education, health insurance coverage, and job categories. Odds ratios were converted into percent increase for ease of interpretation. RESULTS: PM2.5 exposure was associated with broad-category mortality outcomes, including all non-accidental, cardiovascular, cerebrovascular, respiratory, and digestive mortality. A 10-µg/m3 PM2.5 higher cumulative exposure over one week (lag06) was associated with higher cause-specific mortality outcomes including hypertensive disease [2.28% (95%CI: 0.26%-4.33%)], acute ischemic heart disease [1.61% (95%CI: 0.59%-2.64%)], other forms of heart disease [2.39% (95%CI: -0.35%-5.20%)], hemorrhagic stroke [3.63% (95%CI: 0.79%-6.55%)], influenza and pneumonia [4.91% (95%CI: 2.84%-7.02%)], chronic respiratory disease [2.49% (95%CI: 0.71%-4.31%)], diseases of the liver [1.85% (95%CI: 0.31%-3.41%)], and renal failure [3.48% (95%CI: 0.79%-6.24%)]. No differences in effect size of associations were observed between age, sex and SES strata. CONCLUSIONS: Exposure to PM2.5 was associated with non-accidental, broad-category and cause-specific mortality outcomes beyond the cardiovascular and respiratory systems, including specific death-causes from the digestive and genitourinary systems, with no indication of effect modification by individual-level characteristics.
Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Estudios Cruzados , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , México/epidemiología , Material Particulado/efectos adversos , Material Particulado/análisis , Masculino , FemeninoRESUMEN
Background: Being indigenous, being a woman, and living in poverty are social determinants that contribute to reduced access to healthcare, including reproductive health services. The COVID-19 pandemic might have exacerbated this lag. Objective: This study explored how the COVID-19 pandemic affected the contraceptive use of a group of indigenous Mexican women and adolescents in their community. Methods: Between June and December of 2021, 158 indigenous Mexican women who had experienced recurrent pregnancies were interviewed at two health centers in San Cristóbal de las Casas, Chiapas. Participants were either pregnant when they completed the questionnaire or had been pregnant during the COVID-19 pandemic. Women were asked about their contraceptive practices before and during the pandemic. The change in contraceptive practice was estimated using a logistic model. Results: The COVID-19 pandemic reduced contraceptive use by 50%. Among women who wanted contraception, 58% did not receive it. During the pandemic, 77% of previous contraceptive users reported difficulty obtaining contraception, and only 23% sought family planning assistance. Conclusion: During the COVID-19 pandemic, indigenous women in the studied community used fewer contraceptive methods and did not use intrauterine devices. Additionally, there was a decline in the percentage of women using contraceptives. These results highlight the impact on indigenous populations and the difficulties they could face in accessing reproductive health services during health emergencies.
Asunto(s)
COVID-19 , Anticonceptivos , Adolescente , Embarazo , Femenino , Humanos , Estudios Cruzados , Pandemias , Estudios Retrospectivos , COVID-19/epidemiologíaRESUMEN
BACKGROUND: Glycemic variability in patients with type 2 diabetes mellitus (T2DM) may be associated with chronic complications of the disease. Melatonin is a hormone that plays a crucial role in biological rhythms. Previous studies have indicated that individuals with T2DM often exhibit reduced melatonin production. In this study, our objective was to investigate whether nighttime melatonin supplementation could mitigate glycemic variability in these patients. METHODS: Crossover, double-blind, placebo-controlled, randomized study. A total of 30 patients were enrolled in this study. The study included 15 participants who followed the intervention sequence of placebo (7 days)-washout (7 days)-melatonin (3 mg) (7 days), and another 15 participants who followed the sequence of melatonin (3 mg) (7 days)-washout (7 days)-placebo (7 days). During the final three days of the first and third weeks, the participants measured their pre- and postprandial capillary blood glucose levels. This study was reported according to the CONSORT 2010 statement: extension to randomized crossover trials. RESULTS: There was a significant absolute difference in the breakfast blood glucose levels (p = 0.016) on Day 7. The use of melatonin determined a greater positive variation between pre- and postprandial glycemia than the placebo. The difference in glycemic amplitude between post-dinner Day 6 and pre-breakfast Day 7 was also significantly higher in the melatonin group (p = 0.032). CONCLUSIONS: Melatonin increased glycemic variability in individuals with type 2 diabetes mellitus (T2DM). These results can be attributed to the residual daytime effects of melatonin, prospective proximal effects, and damage to the prospective distal effects of exogenous melatonin. Therefore, caution should be exercised when administering melatonin supplementation to patients with T2DM, taking into consideration factors such as dosage, duration of use and genetic considerations.
Asunto(s)
Diabetes Mellitus Tipo 2 , Melatonina , Humanos , Melatonina/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucemia , Estudios Prospectivos , Método Doble CiegoRESUMEN
BACKGROUND: Glycemic variability is recognized as a significant factor contributing to the development of micro- and macrovascular complications in individuals with type 2 diabetes mellitus (T2DM). Numerous studies have shown that melatonin, a hormone involved in regulating various biological rhythms, including those related to glucose regulation, such as hunger, satiety, sleep, and circadian hormone secretion (ie, cortisol, growth hormone, catecholamines, and insulin), is deficient in individuals with T2DM. This raises an important question: Could melatonin replacement potentially reduce glycemic variability in these patients? This warrants investigation as a novel approach to improving glycemic control and reducing the risk of complications associated with T2DM. OBJECTIVE: We aimed to investigate whether melatonin replacement in individuals with T2DM who supposedly have melatonin deficiency can positively impact the regulation of insulin secretion rhythms and improve insulin sensitivity, ultimately resulting in a reduction in glycemic variability. METHODS: This study will use a crossover, randomized, double-blind, placebo-controlled trial design. Patients with T2DM in group 1 will receive 3 mg of melatonin at 9:00 PM in the first week, undergo a washout period in the second week, and receive a placebo in the third week (melatonin-washout-placebo). Group 2 will be randomized to receive a placebo-washout-melatonin sequence (3 mg). Capillary blood glucose levels will be measured at 6 different times before and after meals during the last 3 days of the first and third weeks. The study aims to compare the mean differences in blood glucose levels and the coefficient of glycemic variability in patients receiving melatonin and placebo during the first and third weeks. After analyzing the initial results, the number of needed patients will be recalculated. If the recalculated number is higher than 30, new participants will be recruited. Thirty patients with T2DM will be randomized into the 2 groups: melatonin-washout-placebo or placebo-washout-melatonin. RESULTS: Participant recruitment took place between March 2023 to April 2023. In all, 30 participants were eligible and completed the study. We expect that patients will show different glycemic variability on the days they receive placebo or melatonin. Studies on melatonin and glycemic control have shown both positive and negative results. We hope that there will be a positive outcome regarding glycemic variability (ie, a reduction in glycemic variability), as melatonin has a well-described chronobiotic effect in the literature. CONCLUSIONS: This study aims to determine whether melatonin supplementation can effectively reduce glycemic variability in patients with T2DM. The crossover design is necessary due to the multiple variables involved in the circadian variations of glucose, including diet, physical activity, sleep parameters, and pharmacological treatments. The relatively low cost of melatonin and its potential role in reducing the severe complications associated with T2DM have motivated this research effort. Furthermore, the indiscriminate use of melatonin in current times makes conducting this study essential to evaluate the effect of this substance in patients with T2DM. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials RBR-6wg54rb; https://ensaiosclinicos.gov.br/rg/RBR-6wg54rb. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/47887.
RESUMEN
OBJECTIVE: To evaluate the efficacy of combined association instrument myofascial mobilization (IASTM) and stretching in patients with idiopathic bilateral carpal tunnel syndrome (CTS) operated on one hand and to analyze the response of the operated (OH) and non-operated (NH) hand according to the sequence of therapies. Research on these parameters has not yet been found in the literature. METHODS: Randomized controlled crossover study with 43 participants using the objective and subjective outcome variables. Patients were randomly assigned to two groups: starting with stretching followed by IASTM and starting with IASTM followed by stretching. Then patients underwent surgery on the hand with more severe involvement and physical therapy rehabilitation was started 30 days after for a period of 4 weeks. After the 1-week interval the participants who started with stretching were referred to IASTM and vice versa, following the same previous patterns. The outpatient reassessments took place at 3 to 6 months. Crossover ANOVA and effect sizes were used as analysis methods. RESULTS: Time was the most significant outcome for all variables both during therapies and at 6-month follow-up. Regarding response to the combined therapies between OH and NH, there were differences for both OH and NH, with the greatest impact on NH for the palmar grip and VAS variables. The treatment sequences were significant for pain on the NH and mental SF-12, suggesting that starting with IASTM followed by stretching had a superior outcome for these outcomes. CONCLUSION: The combination of IASTM with stretching, used in the postoperative period of bilateral idiopathic CTS, proved to be supplementary, with significant results and large effect sizes for most of the outcomes assessed, both during the time of application of the therapies and in the 6-month follow-up for both hands, and may constitute a viable therapeutic alternative for this population.
Asunto(s)
Síndrome del Túnel Carpiano , Humanos , Síndrome del Túnel Carpiano/cirugía , Síndrome del Túnel Carpiano/rehabilitación , Estudios Cruzados , Periodo Posoperatorio , Resultado del TratamientoRESUMEN
A model for cross-over designs with repeated measures within each period was developed. It was obtained using an extension of generalized estimating equations that includes a parametric component to model treatment effects and a non-parametric component to model time and carry-over effects; the estimation approach for the non-parametric component is based on splines. A simulation study was carried out to explore the model properties. Thus, when there is a carry-over effect or a functional temporal effect, the proposed model presents better results than the standard models. Among the theoretical properties, the solution is found to be analogous to weighted least squares. Therefore, model diagnostics can be made by adapting the results from a multiple regression. The proposed methodology was implemented in the data sets of the cross-over experiments that motivated the approach of this work: systolic blood pressure and insulin in rabbits.
Asunto(s)
Modelos Estadísticos , Animales , Conejos , Estudios Cruzados , Simulación por Computador , Análisis Multivariante , Análisis de los Mínimos CuadradosRESUMEN
Introduction: Research has evaluated the impact of COVID-19 pandemic and lockdowns on individuals' life satisfaction, but wellbeing interrelations between family members in this context have been less explored. This study examined the spillover and crossover effects of one parent's job satisfaction (JS), satisfaction with family life (SWFaL) and satisfaction with food-related life (SWFoL) on their own, their partner's, and their adolescent children's life satisfaction (LS), and the influence of adolescents' SWFaL and SWFoL on their own and their parents' LS, in dual-earner families with adolescents. The moderating role of job-related variables of both parents were also explored. Methods: Questionnaires were administered to 860 dual-earner parents with adolescents in two cities in Chile during 2020. Mothers and fathers answered the Overall Job Satisfaction Scale and the three family members answered the Satisfaction with Life Scale, the Satisfaction with Family Life Scale and the Satisfaction with Food-related Life Scale. Results: Using the Actor-Partner Interdependence Model and structural equation modeling, we found that fathers' LS was positively associated with their own JS, SWFaL and SWFoL (spillover), and negatively with adolescents' SWFoL (crossover). Likewise, mothers' LS was positively associated with their own JS, SWFaL and SWFoL (spillover), with fathers' and adolescents' SWFaL, and negatively with adolescents' SWFoL. Adolescents' LS was positively associated with their own SWFaL and SWFoL (spillover), and with their fathers' JS, and negatively with their fathers' SWFoL. JS showed gendered patterns in spillover and crossover associations. Parents' type of employment, mothers' working hours and city of residence moderated some spillover and crossover associations for father-mother and parent-adolescent dyads. Discussion: These findings suggest that, for dual-earner parents with adolescents, improving individuals' LS requires interventions that should be carried out not individually, but at a family level.
Asunto(s)
COVID-19 , Pandemias , Femenino , Humanos , Adolescente , Niño , Control de Enfermedades Transmisibles , Padres , Madres , Satisfacción PersonalRESUMEN
Background: Satellite-based PM2.5 predictions are being used to advance exposure science and air-pollution epidemiology in developed countries; including emerging evidence about the impacts of PM2.5 on acute health outcomes beyond the cardiovascular and respiratory systems, and the potential modifying effects from individual-level factors in these associations. Research on these topics is lacking in Latin America. Methods: We used a time-stratified case-crossover study design with 1,479,950 non-accidental deaths from Mexico City Metropolitan Area for the period of 2004-2019. Daily 1×1 km PM2.5 (median=23.4 µg/m3; IQR=13.6 µg/m3) estimates from our satellite-based regional model were employed for exposure assessment at the sub-municipality level. Associations between PM2.5 with broad-category (organ-system) and cause-specific mortality outcomes were estimated with distributed lag conditional logistic models. We also fit models stratifying by potential individual-level effect modifiers including; age, sex, and individual SES-related characteristics namely: education, health insurance coverage, and job categories. Results: PM2.5 exposure was associated with higher total non-accidental, cardiovascular, cerebrovascular, respiratory, and digestive mortality. A 10-µg/m3 PM2.5 higher cumulative exposure over one week (lag06) was associated with higher cause-specific mortality outcomes including hypertensive disease [2.28% (95%CI: 0.26%-4.33%)], acute ischemic heart disease [1.61% (95%CI: 0.59%-2.64%)], other forms of heart disease [2.39% (95%CI: -0.35%-5.20%)], hemorrhagic stroke [3.63% (95%CI: 0.79%-6.55%)], influenza and pneumonia [4.91% (95%CI: 2.84%-7.02%)], chronic respiratory disease [2.49% (95%CI: 0.71%-4.31%)], diseases of the liver [1.85% (95%CI: 0.31%-3.41%)], and renal failure [3.48% (95%CI: 0.79%-6.24%)]. No differences in effect size of associations were observed between SES strata. Conclusions: Exposure to PM2.5 was associated with mortality outcomes beyond the cardiovascular and respiratory systems, including specific death-causes from the digestive and genitourinary systems, with no indications of effect modification by individual SES-related characteristics.
RESUMEN
OBJECTIVE: To evaluate if distinct 20%-22% carbamide peroxide bleaching gels present similar decomposition pattern and pH during the clinical use in both arches, as well as gels viscosity. METHODS: Participants randomly received treatments with carbamide peroxide gels (n = 10): OPF (OpalescencePF-20%); PNT (Polanight-22%); and WPC (Whiteness Perfect-22%) in three different days, with 2-day washout. Decomposition pattern was assessed by peroxide concentration. Both PC and pH of bleaching gels were measured in different time points in upper and lower trays during a total of 120 min of clinical use. Viscosity of bleaching gels was measured in triplicate. ANOVA and Tukey's test were applied (α = 0.05). RESULTS: Regarding decomposition pattern, no significant differences were observed for the interaction between gel, time, and tray position factors. The peroxide concentration progressively reduced until 120 min of trays use (p < 0.001), being overall more notable in lower trays (p < 0.001). Regarding pH, the lowest values were verified in WPC within time. At 120 min, an increase of pH was observed for both WPC and OPF (p < 0.001) compared to baseline means. PNT exhibited constant pH values over time. The values of viscosity were: OPF (1.682.000 ± 19 cP)a, WPC (1.388.667 ± 172.63 cP)ab, PNT (579.567 ± 0.98 cP)b. CONCLUSIONS: The bleaching gels presented overall decomposition pattern clinically equivalent, being more notable in lower trays over time. Nevertheless, distinct pH and viscosities were observed among the products. CLINICAL SIGNIFICANCE: Although the manufacturers recommend different times of use for bleaching gels with similar peroxide concentrations, the commercial products tested did not exhibit clinically relevant difference in the decomposition pattern during the 120 min of clinical procedure.
Asunto(s)
Blanqueadores Dentales , Blanqueamiento de Dientes , Humanos , Peróxido de Carbamida , Geles , Peróxido de Hidrógeno , Peróxidos/química , Blanqueamiento de Dientes/métodos , Blanqueadores Dentales/química , Urea/química , Estudios CruzadosRESUMEN
Specific classes of cyberspaces emphasize different types of digital transactions given the user's context, thus making it essential to take into account what these environments can afford. In this way, we can portray the niches of technological use as ecologies of particular possibilities and compare how they differ between distinct spheres of human life. The present research is focused on describing the conceptual integration of a taxonomic crossover between Virtual Learning Environments and Educational Affordances of Technology, while also performing empirical testing and determining the psychometric properties in a scale regarding the aforementioned taxonomy. The study sample consisted of 320 students in the departments of foreign languages from three different universities in Sonora (northwestern region of Mexico). Students were given a questionnaire of 21 items organized into four subscales with a Likert-type response option to measure the notions concerning their usage of Virtual Learning Environments. Internal consistency procedures and confirmatory factor analysis by means of Cronbach's alpha and Structural modeling support the derived factorial structure, which contains Cyber-Communications, Virtual Behavior Settings, Virtual Communities, and Availability and Access to Connectivity. This structure traces the environmental properties perceived by learners in a virtual environment. Results sustain the initial conceptual construction regarding the proposed taxonomy, conclude that the 'Virtual Learning Environments Questionnaire' demonstrates adequate psychometric properties, and validate it as a fitting measure to assess the perceived psychological experience of students in a digital educational setting.
RESUMEN
The one-dimensional Galerkin-truncated Burgers equation, with both dissipation and noise terms included, is studied using spectral methods. When the truncation-scale Reynolds number [Formula: see text] is varied, from very small values to order 1 values, the scale-dependent correlation time [Formula: see text] is shown to follow the expected crossover from the short-distance [Formula: see text] Edwards-Wilkinson scaling to the universal long-distance Kardar-Parisi-Zhang scaling [Formula: see text]. In the inviscid limit, [Formula: see text], we show that the system displays another crossover to the Galerkin-truncated inviscid-Burgers regime that admits thermalized solutions with [Formula: see text]. The scaling forms of the time-correlation functions are shown to follow the known analytical laws and the skewness and excess kurtosis of the interface increments distributions are characterized. This article is part of the theme issue 'Scaling the turbulence edifice (part 2)'.
RESUMEN
Background: Climate change is increasing the risks of injuries, diseases, and deaths globally. However, the association between ambient temperature and renal diseases has not been fully characterized. This study aimed to quantify the risk and attributable burden for hospitalizations of renal diseases related to ambient temperature. Methods: Daily hospital admission data from 1816 cities in Brazil were collected during 2000 and 2015. A time-stratified case-crossover design was applied to evaluate the association between temperature and renal diseases. Relative risks (RRs), attributable fractions (AFs), and their confidence intervals (CIs) were calculated to estimate the associations and attributable burden. Findings: A total of 2,726,886 hospitalizations for renal diseases were recorded during the study period. For every 1°C increase in daily mean temperature, the estimated risk of hospitalization for renal diseases over lag 0-7 days increased by 0·9% (RR = 1·009, 95% CI: 1·008-1·010) at the national level. The associations between temperature and renal diseases were largest at lag 0 days but remained for lag 1-2 days. The risk was more prominent in females, children aged 0-4 years, and the elderly ≥ 80 years. 7·4% (95% CI: 5·2-9·6%) of hospitalizations for renal diseases could be attributable to the increase of temperature, equating to 202,093 (95% CI: 141,554-260,594) cases. Interpretation: This nationwide study provides robust evidence that more policies should be developed to prevent heat-related hospitalizations and mitigate climate change. Funding: China Scholarship Council, and the Australian National Health and Medical Research Council.