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1.
Circulation ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39166326

RESUMO

BACKGROUND: Coronary microvascular dysfunction has been implicated in the development of hypertensive heart disease and heart failure, with subendocardial ischemia identified as a driver of sustained myocardial injury and fibrosis. We aimed to evaluate the relationships of subendocardial perfusion with cardiac injury, structure, and a composite of major adverse cardiovascular and cerebral events consisting of death, heart failure hospitalization, myocardial infarction, and stroke. METHODS: Layer-specific blood flow and myocardial flow reserve (MFR; stress/rest myocardial blood flow) were assessed by 13N-ammonia perfusion positron emission tomography in consecutive patients with hypertension without flow-limiting coronary artery disease (summed stress score <3) imaged at Brigham and Women's Hospital (Boston, MA) from 2015 to 2021. In this post hoc observational study, biomarkers, echocardiographic parameters, and longitudinal clinical outcomes were compared by tertiles of subendocardial MFR (MFRsubendo). RESULTS: Among 358 patients, the mean age was 70.6±12.0 years, and 53.4% were male. The median MFRsubendo was 2.57 (interquartile range, 2.08-3.10), and lower MFRsubendo was associated with older age, diabetes, lower renal function, greater coronary calcium burden, and higher systolic blood pressure (P<0.05 for all). In cross-sectional multivariable regression analyses, the lowest tertile of MFRsubendo was associated with myocardial injury and with greater left ventricular wall thickness and volumes compared with the highest tertile. Relative to the highest tertile, low MFRsubendo was independently associated with an increased rate of major adverse cardiovascular and cerebral events (adjusted hazard ratio, 2.99 [95% CI, 1.39-6.44]; P=0.005) and heart failure hospitalization (adjusted hazard ratio, 2.76 [95% CI, 1.04-7.32; P=0.042) over 1.1 (interquartile range, 0.6-2.8) years median follow-up. CONCLUSIONS: Among patients with hypertension without flow-limiting coronary artery disease, impaired MFRsubendo was associated with cardiovascular risk factors, elevated cardiac biomarkers, cardiac structure, and clinical events.

2.
Nat Mater ; 22(9): 1144-1151, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37580369

RESUMO

Ferroelectricity in binary oxides including hafnia and zirconia has riveted the attention of the scientific community due to the highly unconventional physical mechanisms and the potential for the integration of these materials into semiconductor workflows. Over the last decade, it has been argued that behaviours such as wake-up phenomena and an extreme sensitivity to electrode and processing conditions suggest that ferroelectricity in these materials is strongly influenced by other factors, including electrochemical boundary conditions and strain. Here we argue that the properties of these materials emerge due to the interplay between the bulk competition between ferroelectric and structural instabilities, similar to that in classical antiferroelectrics, coupled with non-local screening mediated by the finite density of states at surfaces and internal interfaces. Via the decoupling of electrochemical and electrostatic controls, realized via environmental and ultra-high vacuum piezoresponse force microscopy, we show that these materials demonstrate a rich spectrum of ferroic behaviours including partial-pressure-induced and temperature-induced transitions between ferroelectric and antiferroelectric behaviours. These behaviours are consistent with an antiferroionic model and suggest strategies for hafnia-based device optimization.

3.
Environ Res ; 256: 119212, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38797462

RESUMO

INTRODUCTION: Adverse pregnancy outcomes (APOs) include stillbirth, preterm birth, and low birthweight (LBW). Studies exploring the impact of weather factors and air pollution on APOs are scarce in Nepal. We examined the impacts of prenatal exposure to temperature, precipitation, and air pollution (PM2.5) on APOs among women living in Kavre, Nepal. METHODS: We conducted a hospital and rural health centers-based historical cohort study that included health facility birth records (n = 1716) from the Nepali fiscal year 2017/18 through 2019/20. We linked health records to temperature, precipitation, and PM2.5 data for Kavre for the six months preceding each birth. A random intercept model was used to analyze birthweight, while a composite APO variable, was analyzed using multivariable logistic regression in relation to environmental exposures. RESULTS: The proportion of LBW (<2500 gm), preterm birth (babies born alive before 37 weeks of gestation), and stillbirth was 13%, 4.3%, and 1.5%, respectively, in this study. Overall, around 16% of the study participants had one or more APOs. Total precipitation (ß: 0.17, 95% CI 0.01 to 0.33, p = 0.03) had a positive effect on birthweight in the wetter season. Negative effects for mean maximum (ß: 33.37, 95% CI -56.68 to -10.06, p = 0.005), mean (ß: 32.35, 95% CI -54.44 to -10.27, p = 0.004), and mean minimum temperature (ß: 29.28, 95% CI -49.58 to -8.98, p = 0.005) on birthweight was also observed in the wetter season. CONCLUSION: A positive effect of temperature (mean maximum, mean, and mean minimum) and total precipitation on birthweight was found in the wetter season. This study emphasizes the need for future research using larger cohorts to elucidate these complex relationships in Nepal.


Assuntos
Poluição do Ar , Material Particulado , Resultado da Gravidez , Nascimento Prematuro , Tempo (Meteorologia) , Nepal/epidemiologia , Humanos , Feminino , Gravidez , Material Particulado/análise , Adulto , Resultado da Gravidez/epidemiologia , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Adulto Jovem , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/induzido quimicamente , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Estudos de Coortes , Recém-Nascido , Recém-Nascido de Baixo Peso , Natimorto/epidemiologia , Exposição Materna/efeitos adversos , Exposição Materna/estatística & dados numéricos
4.
Can J Neurol Sci ; 51(2): 289-292, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37519226

RESUMO

Exposure to industrial pollutants is a potential risk factor not fully explored in ASD with regression (ASD+R). We studied geographical collocation patterns of industrial air chemical emissions and the location of homes of children with ASD+R at different exposure times, compared with ASD cases without regression (ASD-R). Fifteen of 111 emitted chemicals collocated with ASD+R, and 65 with ASD-R. ASD+R collocated more strongly with different neurotoxicants/immunotoxicants a year before diagnosis, whereas ASD-R were moderately collocated with chemicals across all exposure periods. This preliminary exploratory analysis of differences in exposure patterns raises a question regarding potential pathophysiological differences between the conditions.


Assuntos
Poluentes Atmosféricos , Transtorno do Espectro Autista , Transtorno Autístico , Criança , Humanos , Poluentes Atmosféricos/análise , Fatores de Risco , Razão de Chances , Exposição Ambiental/efeitos adversos
5.
Soc Psychiatry Psychiatr Epidemiol ; 59(4): 695-704, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37017657

RESUMO

INTRODUCTION: Existing literature shows that increased community engagement is associated with decreased depressive symptoms. To our knowledge, no existing studies have investigated the relationship between community engagement and adverse mental health among mothers in a Canadian context, nor has this relationship been studied over time. The current study aims to address these gaps by modelling the association between community engagement and anxiety and depression longitudinally using a cohort of prenatal and postnatal mothers living in Calgary, Alberta. METHODS: We used data from the All our Families (AOF) study, a prospective cohort study of expectant and new mothers in Calgary, Alberta from 2008 to 2017 across seven timepoints. We used three-level latent growth curves to model the relationship between individual-level community engagement and maternal depression and anxiety scores, while adjusting for both individual and neighborhood-level characteristics. RESULTS: The study sample consisted of 2129 mothers across 174 neighborhoods in Calgary. Adjusted latent growth curve models demonstrated that community engagement was associated with lower depression (b = - 0.28, 95% CI - 0.33, - 0.23) and anxiety (b = - 0.07, 95% CI - 0.12, - 0.02) scores among mothers over time. DISCUSSION: Adjusted results show that community engagement has a protective effect against depression and anxiety amongst mothers. The results of this study are in line with existing evidence suggesting that social cohesion, civic participation, and community engagement are protective against adverse mental health outcomes.


Assuntos
Saúde Mental , Mães , Feminino , Gravidez , Humanos , Alberta/epidemiologia , Estudos Prospectivos , Mães/psicologia , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/epidemiologia , Depressão/psicologia
6.
BMC Pregnancy Childbirth ; 23(1): 710, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794335

RESUMO

BACKGROUND: Independently, active maternal and environmental tobacco smoke exposure and maternal stress have been linked to an increased risk of preterm birth and low birth weight. An understudied relationship is the potential for interactive effects between these risk factors. METHODS: Data was obtained from the All Our Families cohort, a study of 3,388 pregnant women < 25 weeks gestation recruited from those receiving prenatal care in Calgary, Canada between May 2008 and December 2010. We investigated the joint effects of active maternal smoking, total smoke exposure (active maternal smoking plus environmental tobacco smoke) and prenatal stress (Perceived Stress Scale, Spielberger State-Trait Anxiety Inventory), measured at two time points (< 25 weeks and 34-36 weeks gestation), on preterm birth and low birth weight. RESULTS: A marginally significant association was observed with the interaction active maternal smoking and Spielberger State-Trait Anxiety Inventory scores in relation to low birth weight, after imputation (aOR = 1.02, 95%CI: 1.00-1.03, p = 0.06). No significant joint effects of maternal stress and either active maternal smoking or total smoke exposure with preterm birth were observed. Active maternal smoking, total smoke exposure, Perceived Stress Scores, and Spielberger State-Trait Anxiety Inventory scores were independently associated with preterm birth and/or low birth weight. CONCLUSIONS: Findings indicate the role of independent effects of smoking and stress in terms of preterm birth and low birthweight. However, the etiology of preterm birth and low birth weight is complex and multifactorial. Further investigations of potential interactive effects may be useful in helping to identify women experiencing vulnerability and inform the development of targeted interventions.


Assuntos
Nascimento Prematuro , Fumar , Poluição por Fumaça de Tabaco , Feminino , Humanos , Recém-Nascido , Gravidez , Recém-Nascido de Baixo Peso , Exposição Materna/efeitos adversos , Nascimento Prematuro/etiologia , Nascimento Prematuro/induzido quimicamente , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Gestantes/psicologia
7.
BMC Geriatr ; 23(1): 439, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464306

RESUMO

BACKGROUND AND OBJECTIVES: Although the positive influence of social activity on health is now well-established, a complex relationship exists among social participation, personal, social and the environment. Social participation of older adults was examined in rural and urban settings to identify features of the built-environment and perception of neighborhood specific to the locale. RESEARCH DESIGN AND METHODS: Using cross-sectional data from the Canadian Longitudinal Study on Aging (CLSA), we examined social participation and health of older people (65 + yrs) in relation to the built environment and sociocultural contexts for urban and rural areas. A social participation index was derived from responses on the frequency of participating in 8 social activities over the past 12 months. Personal, household and neighborhood indicators were examined to develop multivariable regression models for social participation in urban and rural cohorts. RESULTS: No meaningful differences were seen with the frequency of social participation between rural and urban settings; however, the type of community-related activities differed in that a greater proportion of urban participants reported sports and educational/cultural events than rural participants. Service club activities were greater for rural than urban participants. Different neighborhood features were statistically significant factors in explaining social participation in rural than in urban locales, although transportation was a significant factor regardless of locale. Trustworthiness, belonging and safety were perceived factors of the neighborhood associated with higher social participation for rural participants. DISCUSSION AND IMPLICATIONS: The relationship between home and health becomes stronger as one ages. Social and physical features of built environment specific to urban and rural settings need to be considered when implementing appropriate social activities for older people.


Assuntos
Envelhecimento , Participação Social , Humanos , Idoso , Estudos Longitudinais , Canadá/epidemiologia , Estudos Transversais , População Urbana , População Rural
8.
Eur Spine J ; 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36740609

RESUMO

PURPOSE: To utilize natural language processing (NLP) of MRI reports and various clinical variables to develop a preliminary model predictive of the need for surgery in patients with low back and neck pain. Such a model would be beneficial for informing clinical practice decisions and help reduce the number of unnecessary surgical referrals, streamlining the surgical process. METHODS: A historical cohort study was conducted using de-identified data from patients referred to a spine assessment clinic. Various demographic, clinical, and radiological variables were included as potential predictors. Full-text radiology reports of patients' MRI findings were vectorized using NLP before applying machine learning algorithms to develop models predicting who underwent surgery. Outputs from these models were then entered into a logistic regression model with clinical variables to develop a preliminary model predictive of surgical recommendations. RESULTS: Of the 398 patients assessed, 71 underwent spine surgery. NLP variables were significant predictors in univariate analysis but did not remain in the final logistic regression model. An outcome of receiving surgery was predicted by a primary symptom of low back and leg pain (adjusted odds ratio 2.81), distal pain indicated by a pain diagram (adjusted odds ratio 2.49) and self-reported difficulties walking (adjusted odds ratio 2.73). CONCLUSION: A logistic regression model was created to predict which patients may require spine surgery. Simple clinical variables appeared more predictive than variables created using NLP. However, additional research with more data samples is needed to validate this model and fully evaluate the usefulness of NLP for this task.

9.
BMC Pediatr ; 22(1): 432, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858855

RESUMO

BACKGROUND: Research on intra- and inter-regional variations in emergency department (ED) visits among children can provide a better understanding of the patterns of ED utilization and further insight into how contextual features of the urban environment may be associated with these health events. Our objectives were to assess intra-urban and inter-urban variation in paediatric emergency department (PED) visits in census metropolitan areas (CMAs) in Ontario and Alberta, Canada and explore if contextual factors related to material and social deprivation, proximity to healthcare facilities, and supply of family physicians explain this variation. METHODS: A retrospective, population-based analysis of data on PED visits recorded between April 1, 2015 and March 31, 2017 was conducted. Random intercept multilevel regression models were constructed to quantify the intra- (between forward sortation areas [FSAs]) and inter- (between CMAs) variations in the rates of PED visits. RESULTS: In total, 2,537,442 PED visits were included in the study. The overall crude FSA-level rate of PED visits was 415.4 per 1,000 children population. Across CMAs, the crude rate of PED visits was highest in Thunder Bay, Ontario (771.6) and lowest in Windsor, Ontario (237.2). There was evidence of substantial intra- and inter-urban variation in the rates of PED visits. More socially deprived FSAs, FSAs with decreased proximity to healthcare facilities, and CMAs with a higher rate of family physicians per 1,000 children population had higher rates of PED visits. CONCLUSIONS: The variation in rates of PED visits across CMAs and FSAs cannot be fully accounted for by age and sex distributions, material and social deprivation, proximity to healthcare facilities, or supply of family physicians. There is a need to explore additional contextual factors to better understand why some metropolitan areas have higher rates of PED visits.


Assuntos
Serviço Hospitalar de Emergência , Alberta/epidemiologia , Criança , Humanos , Análise Multinível , Ontário/epidemiologia , Estudos Retrospectivos
10.
J Occup Rehabil ; 31(4): 768-784, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33751310

RESUMO

PURPOSE: Public safety personnel (PSP) are at risk of developing posttraumatic stress injury (PTSI) due to exposure to traumatic experiences and accidents. Rehabilitation programs are available, but their success varies. We studied: (1) characteristics of PSP undergoing PTSI rehabilitation in comparison to non-PSP workers; and (2) predictive value of various factors for return to work. Methods A population-based cohort study was conducted using data on injured workers undergoing PTSI rehabilitation. Of the 488 workers included, 131 were PSP. Outcome measures were: (1) return to pre-accident work at rehabilitation discharge; (2) days receiving wage replacement benefits in the year following rehabilitation. Results PSP were mainly employed (90.8%), male (59.5%), paramedics/ambulance workers (58.0%); a minority (43.5%) returned to pre-accident work after rehabilitation. Compared to non-PSP workers, PSP were more likely to initially be diagnosed with psychological injuries (94.7% versus 59.4%, p < 0.001) rather than musculoskeletal injuries. Return to pre-accident work was predicted by shorter injury duration, having a primary mental health diagnosis, working at time of admission, and not having symptoms requiring treatment in a complex rehabilitation program. PSPs were slower to experience full recovery in the year after rehabilitation. Factors predicting fewer benefit days included not having a secondary psychological injury, being employed, and working at time of admission. Conclusions Most PSP did not return to work in full after PTSI rehabilitation. Outcomes are likely to improve by starting treatment earlier and maintaining connections with the workplace.


Assuntos
Doenças Musculoesqueléticas , Transtornos de Estresse Pós-Traumáticos , Estudos de Coortes , Humanos , Masculino , Prognóstico , Retorno ao Trabalho , Indenização aos Trabalhadores
11.
Neuroimage ; 199: 57-69, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31128246

RESUMO

Trends toward encephalization and technological complexity ∼1.8 million years ago may signify cognitive development in the genus Homo. Using functional near-infrared spectroscopy, we measured relative brain activity of 33 human subjects at three different points as they learned to make replicative Oldowan and Acheulian Early Stone Age tools. Here we show that the more complex early Acheulian industry recruits left dorsolateral prefrontal cortex when skills related to this task are first being learned. Individuals with increased activity in this area are the most proficient at the Acheulian task. The Oldowan task, on the other hand, transitions to automatic processing in less than 4 h of training. Individuals with increased sensorimotor activity demonstrate the most skill at this task. We argue that enhanced working memory abilities received positive selection in response to technological needs during the early Pleistocene, setting Homo on the path to becoming human.


Assuntos
Evolução Biológica , Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Atividade Motora/fisiologia , Destreza Motora/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Feminino , Humanos , Masculino , Neuroimagem , Córtex Pré-Frontal/diagnóstico por imagem , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
12.
Appetite ; 142: 104328, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31238080

RESUMO

Geophagy, the craving and intentional consumption of soil, is common especially among pregnant women in some low- and middle-income settings. Soils may contain a variety of non-nutritive components such as heavy metals and microbes or substances that interfere with gastrointestinal absorptive processes, posing health risks to pregnant women. Several hypotheses regarding the practice have been proposed but very few have examined the role of maternal stress. The practice of geophagy may help to alleviate stress or anxiety during gestation from perceived dietary or other pregnancy-related concerns. In this study, we evaluated several measures of maternal stress (general anxiety, Pregnancy-Related Anxiety Scores (10-item revised), and Perceived Stress Scores) and other covariates in relation to geophagic behaviour in early pregnancy in 227 women (12-19 weeks gestation) recruited from two hospitals in the Nyamagana district of Mwanza City, Tanzania. Geophagy was reported by 24.7% of the pregnant women. Using LASSO regression, self-reported treatment of nausea or vomiting during pregnancy (adjusted OR = 3.12, 95%CI: 1.43 to 6.83), paternal education level (adjusted OR = 2.79, 95%CI: 1.32 to 5.87 for primary or lower education level), antenatal hospital site (adjusted OR = 3.71, 95%CI: 1.78 to 7.75), prescription drug use prior to pregnancy (adjusted OR = 1.76, 95%CI: 0.87 to 3.56) and general anxiety (feeling worried, tense or anxious in the past four weeks) (adjusted OR = 1.81, 95%CI: 0.88 to 3.72) were associated with geophagic behaviour. Given that relatively little has been done to examine geophagy in relation to the public health risk it may pose to pregnant women, these findings suggest the need for further investigations regarding maternal stress.


Assuntos
Ansiedade/psicologia , Pica/psicologia , Complicações na Gravidez/psicologia , Gestantes/psicologia , Estresse Psicológico/psicologia , Adulto , Feminino , Idade Gestacional , Humanos , Pica/epidemiologia , Gravidez , Tanzânia/epidemiologia
14.
Matern Child Health J ; 22(11): 1563-1567, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29936655

RESUMO

Purpose Home visiting programs have produced inconsistent outcomes. One challenge for the field is the design and implementation of effective training to support home visiting staff. In part due to a lack of formal training, most home visitors need to develop the majority of their skills on the job. Home visitors typically receive training in their agency's specific model (e.g., HFA, NFP) and, if applicable, curriculum. Increasingly, states and other home visiting systems are developing and/or coordinating more extensive training and support systems beyond model-specific and curricula trainings. To help guide these training efforts and future evaluations of them, this paper reviews research on effective training, particularly principles of training transfer and adult learning. Description Our review summarizes several meta-analyses, reviews, and more recent publications on training transfer and adult learning principles. Assessment Effective training involves not only the introduction and modeling of concepts and skills but also the practice of, evaluation of, and reflection upon these skills. Further, ongoing encouragement of, reward for, and reflection upon use of these skills, particularly by a home visitor's supervisor, are critical for the home visitor's continued use of these skills with families. Conclusion Application of principles of adult learning and training transfer to home visiting training will likely lead to greater transfer of skills from the training environment to work with families. The involvement of both home visitors and their supervisors in training is likely important for this transfer to occur.


Assuntos
Enfermagem em Saúde Comunitária/normas , Educação Profissionalizante/organização & administração , Visita Domiciliar , Capacitação em Serviço , Competência Profissional , Adulto , Feminino , Humanos , Masculino
15.
J Educ Psychol ; 110(7): 974-991, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30778263

RESUMO

This 14 year prospective study investigated the effect of retention in grades 1-5 on high school completion (diploma, GED, or drop out). Participants were 734 (52.7% males) ethnically diverse, academically at-risk students recruited from Texas schools into the study when they were in first grade (mean age = 6.57). Propensity score weighting successfully equated the 256 retained students and the 478 students continuously promoted students on 65 covariates assessed in grade 1. At the end of 14 years, 477 had earned a diploma, 21 had obtained a GED, 110 had dropped out, and 126 were missing school completion status. Using multinomial logistic regression with high school graduation as the reference outcome, retention led to a significant increase in the likelihood of dropping out of high school (odds ratio = 2.61), above students' propensity to be retained and additional covariates. The contrast between graduation and GED outcomes was not significant. A significant Retention X Ethnicity X Gender interaction was obtained: The negative effect of retention was strongest for African American and Hispanic girls. Even though grade retention in the elementary grades does not harm students in terms of their academic achievement or educational motivation at the transition to high school, retention increases the odds that a student will drop out of school before obtaining a high school diploma.

16.
Appetite ; 87: 160-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25555536

RESUMO

Differences in parental feeding practices revealed across and within different ethnic/cultural groups indicate that cultural examinations of feeding practices in understudied non-European-American populations require urgent attention. China ranks as the second largest source country for children in foreign-born U.S. households. Contrary to the stereotype of slender Asians, Chinese-American young children are at high risk for obesity but have not received sufficient attention from researchers and practitioners dealing with parental feeding practices and childhood obesity. The present study aimed to understand food-related parenting practices among Chinese immigrants in the U.S. using qualitative focus groups. Twenty-two mothers with preschool aged children participated in a discussion regarding parent-child food-related interactions and feeding practices. A thematic approach was adopted to analyze the focus group data following five stages of framework analysis. Thirteen key themes of feeding practices were identified, including 9 that are in existing feeding measures (pre-exiting practices) and 4 practices that have not been documented or emphasized in previous feeding measures (culturally-emphasized practices), including regulating healthy routines and food energy, spoon-feeding, using social comparison to pressure the child to eat, and making an effort to prepare/cook specific foods. Through the use of an emic approach and meaning-centered evidence, the complexities of parent-child interactions and unique nuances of parental feeding in this understudied population were revealed. Our findings can guide future development of culturally-appropriate measurement and inform intervention programs to promote the healthy development of Chinese-American children.


Assuntos
Cultura , Emigrantes e Imigrantes , Comportamento Alimentar , Mães , Relações Pais-Filho , Obesidade Infantil/etiologia , Adulto , Criança , Educação Infantil , Pré-Escolar , Emigração e Imigração , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Poder Familiar , Pesquisa Qualitativa , Estados Unidos/etnologia
17.
Tob Induc Dis ; 222024.
Artigo em Inglês | MEDLINE | ID: mdl-38560550

RESUMO

INTRODUCTION: The use of e-cigarettes (ECs) has reached unprecedented levels, due to a variety of reasons, including the misconception regarding their safety. Thus, there have been efforts to characterize the effects of EC exposure, including in the context of thirdhand EC (THEC) on a host of disorders, such as cardiovascular disease (CVD). METHODS: To address this issue, we sought to characterize the effects of THEC on platelet function and thrombus formation, using a novel mouse exposure protocol that resembles real life scenarios. To assess these effects, a host of related in vivo (i.e. tail bleeding time, and ferric chloride injury induced thrombosis model) assays and in vitro platelet specific (e.g. aggregation, and dense granule secretion) investigative assays were conducted. RESULTS: Our in vivo characterization demonstrated that THEC exposed mice exhibited a prothrombotic phenotype reflected by their shortened tail bleeding (THEC: 37 ± 15 seconds, versus clean air: 183 ± 56 s) and occlusion times (THEC: 188 ± 39 s, versus clean air: 519 ± 70 s), relative to those exposed to clean air. Importantly, we found no difference in the platelet counts between the THEC and clean air mice. As for the underlying mechanism, separate experiments revealed significantly enhanced platelet aggregation, dense and alpha granule secretion, as well as integrin/GPIIb-IIIa activation and phosphatidylserine exposure in response to thrombin and ADP agonist stimulation. CONCLUSIONS: Taken together, these results provide evidence that THEC does have the capacity to increase the risk of thrombotic disease, which should increase awareness regarding its underappreciated negative health effects.

18.
Artigo em Inglês | MEDLINE | ID: mdl-37703163

RESUMO

As ferroelectric hafnium zirconium oxide (HZO) becomes more widely utilized in ferroelectric microelectronics, integration impacts of intentional and nonintentional dielectric interfaces and their effects upon the ferroelectric film wake-up (WU) and circuit parameters become important to understand. In this work, the effect of the addition of a linear dielectric aluminum oxide, Al2O3, below a ferroelectric Hf0.58Zr0.42O2 film in a capacitor structure for FeRAM applications with niobium nitride (NbN) electrodes was measured. Depolarization fields resulting from the linear dielectric is observed to induce a reduction of the remanent polarization of the ferroelectric. Addition of the aluminum oxide also impacts the WU of the HZO with respect to the cycling voltage applied. Intricately linked to the design of a FeRAM 1C/1T cell, the metal-ferroelectric-insulator-metal (MFIM) devices are observed to significantly shift charge related to the read states based on aluminum oxide thickness and WU cycling voltage. A 33% reduction in the separation of read states are measured, which complicates how a memory cell is designed and illustrates the importance of clean interfaces in devices.

19.
J Cardiovasc Pharmacol Ther ; 29: 10742484241242702, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38592084

RESUMO

INTRODUCTION: It is well documented that cardiovascular disease (CVD) is the leading cause of death in the US and worldwide, with smoking being the most preventable cause. Additionally, most smokers die from thrombotic-based diseases, in which platelets play a major role. To this end, because of the proven harm of smoking, several novel tobacco products such as electronic(e)-waterpipe have been gaining popularity among different sectors of the population, partly due to their "false" safety claims. While many investigators have focused on the negative health effects of traditional cigarettes and e-cigarettes on the cardiovascular system, virtually little or nothing is known about e-waterpipes, which we investigated herein. METHODS AND MATERIALS: To investigate their occlusive CVD effects, we employed a whole-body mouse exposure model of e-waterpipe vape/smoke and exposed C57BL/6J male mice (starting at 7 weeks of age) for 1 month, with the controls exposed to clean air. Exposures took place seven times a week, according to the well-known Beirut protocol, which has been employed in many studies, as it mimics real-life waterpipe exposure scenarios; specifically, 171 puffs of 530 ml volume of the e-liquid at 2.6 s puff duration and 17 s puff interval. RESULTS: The e-waterpipe exposed mice had shortened bleeding and occlusion times, when compared to the clean air controls, indicating a prothrombotic phenotype. As for the mechanism underlying this phenotype, we found that e-waterpipe exposed platelets exhibited enhanced agonist-triggered aggregation and dense granule secretion. Also, flow cytometry analysis of surface markers of platelet activation showed that both P-selectin and integrin GPIIb-IIIa activation were enhanced in the e-waterpipe exposed platelets, relative to the controls. Finally, platelet spreading and Akt phosphorylation were also more pronounced in the exposed mice. CONCLUSION: We document that e-waterpipe exposure does exert untoward effects in the context of thrombosis-based CVD, in part, via promoting platelet hyperreactivity.


Assuntos
Doenças Cardiovasculares , Sistemas Eletrônicos de Liberação de Nicotina , Fumar Cachimbo de Água , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Doenças Cardiovasculares/etiologia , Modelos Animais de Doenças , Eletrônica
20.
ACS Nano ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017620

RESUMO

Better techniques for imaging ferroelectric polarization would aid the development of new ferroelectrics and the refinement of old ones. Here we show how scanning transmission electron microscope (STEM) electron beam-induced current (EBIC) imaging reveals ferroelectric polarization with obvious, simply interpretable contrast. Planar imaging of an entire ferroelectric hafnium zirconium oxide (Hf0.5Zr0.5O2, HZO) capacitor shows an EBIC response that is linearly related to the polarization determined in situ with the positive-up, negative-down (PUND) method. The contrast is easily calibrated in MV/cm. The underlying mechanism is magnification-independent, operating equally well on micrometer-sized devices and individual nanoscale domains. Coercive-field mapping reveals that individual domains are biased "positive" and "negative", as opposed to being "easy" and "hard" to switch. The remanent background E-fields generating this bias can be isolated and mapped. Coupled with STEM's native capabilities for structural identification, STEM EBIC imaging provides a revolutionary tool for characterizing ferroelectric materials and devices.

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