Tag: nevin manimala

Environ Int. 2023 Jun 8;178:108005. doi: 10.1016/j.envint.2023.108005. Online ahead of print.

ABSTRACT

Many United States (US) cities are experiencing urban heat islands (UHIs) and climate change-driven temperature increases. Extreme heat increases cardiovascular disease (CVD) risk, yet little is known about how this association varies with UHI intensity (UHII) within and between cities. We aimed to identify the urban populations most at-risk of and burdened by heat-related CVD morbidity in UHI-affected areas compared to unaffected areas. ZIP code-level daily counts of CVD hospitalizations among Medicare enrollees, aged 65-114, were obtained for 120 US metropolitan statistical areas (MSAs) between 2000 and 2017. Mean ambient temperature exposure was estimated by interpolating daily weather station observations. ZIP codes were classified as low and high UHII using the first and fourth quartiles of an existing surface UHII metric, weighted to each have 25% of all CVD hospitalizations. MSA-specific associations between ambient temperature and CVD hospitalization were estimated using quasi-Poisson regression with distributed lag non-linear models and pooled via multivariate meta-analyses. Across the US, extreme heat (MSA-specific 99th percentile, on average 28.6 °C) increased the risk of CVD hospitalization by 1.5% (95% CI: 0.4%, 2.6%), with considerable variation among MSAs. Extreme heat-related CVD hospitalization risk in high UHII areas (2.4% [95% CI: 0.4%, 4.3%]) exceeded that in low UHII areas (1.0% [95% CI: -0.8%, 2.8%]), with upwards of a 10% difference in some MSAs. During the 18-year study period, there were an estimated 37,028 (95% CI: 35,741, 37,988) heat-attributable CVD admissions. High UHII areas accounted for 35% of the total heat-related CVD burden, while low UHII areas accounted for 4%. High UHII disproportionately impacted already heat-vulnerable populations; females, individuals aged 75-114, and those with chronic conditions living in high UHII areas experienced the largest heat-related CVD impacts. Overall, extreme heat increased cardiovascular morbidity risk and burden in older urban populations, with UHIs exacerbating these impacts among those with existing vulnerabilities.

PMID:37437316 | DOI:10.1016/j.envint.2023.108005

J Chem Theory Comput. 2023 Jul 12. doi: 10.1021/acs.jctc.3c00387. Online ahead of print.

ABSTRACT

We report a Monte Carlo simulation study of length-scale-dependent density fluctuations in cavities in the coarse-grained mW representation of water at ambient conditions. Specifically, we use a combination of test particle insertion and umbrella sampling techniques to examine the full range of water occupation states in spherical cavities up to 6.3 Å radius in water. As has previously been observed, water density fluctuations are found to be effectively Gaussian in nature for atomic-scale cavities, but as the cavities get larger, they exhibit a non-Gaussian “fat-tail” distribution for lower occupancy states. We introduce a new statistical thermodynamic approach to analyze non-Gaussian fluctuations based on the radial distribution of waters about cavities with varying numbers of waters within its boundaries. It is shown that the onset of these non-Gaussian fluctuations is a result of the formation of a bubble within the cavity as it is emptied, which is accompanied by the adsorption of waters onto its interior surface. We revisit a theoretical framework we previously introduced to describe Gaussian fluctuations within cavities to incorporate bubble formation by including surface tension contributions. This modified theory accurately describes density fluctuations within both atomic and meso-scale cavities. Moreover, the theory predicts the transition from Gaussian to non-Gaussian fluctuations at a specific cavity occupancy, in excellent agreement with simulation observations.

PMID:37437298 | DOI:10.1021/acs.jctc.3c00387

J Clin Endocrinol Metab. 2023 Jul 13:dgad414. doi: 10.1210/clinem/dgad414. Online ahead of print.

ABSTRACT

CONTEXT: The inclusion of transgender people in elite sport has been a topic of debate. This narrative review examines the impact of gender affirming hormone therapy (GAHT) on physical performance, muscle strength and markers of endurance.

EVIDENCE ACQUISITION: MEDLINE and Embase were searched using terms to define the population (transgender), intervention (GAHT) and physical performance outcomes.

EVIDENCE SYNTHESIS: Existing literature is comprised of cross-sectional or small uncontrolled longitudinal studies of short duration. In non-athletic trans men starting testosterone therapy, within 1 year, muscle mass and strength increased, and by 3 years, physical performance (push-ups, sit-ups, run time) improved to the level of cisgender men.In non-athletic trans women, feminising hormone therapy increased fat mass by approximately 30% and decreased muscle mass by approximately 5% after 12 months and steadily declined beyond 3 years. Whilst absolute lean mass remains higher in trans women, relative percentage lean mass and fat mass (and muscle strength corrected for lean mass), hemoglobin and VO2 peak corrected for weight was no different to cisgender women. After 2 years of GAHT, no advantage was observed for physical performance measured by running time or in trans women. By 4 years, there was no advantage in sit-ups. Whilst push-ups performance declined in trans women, a statistical advantage remained relative to cisgender women.

CONCLUSIONS: Limited evidence suggests that physical performance of non-athletic trans people who have undergone GAHT for at least 2 years approaches that of cisgender controls. Further controlled longitudinal research is needed in trans athletes and non-athletes.

PMID:37437247 | DOI:10.1210/clinem/dgad414

Cutan Ocul Toxicol. 2023 Jul 12:1-8. doi: 10.1080/15569527.2023.2235429. Online ahead of print.

ABSTRACT

PURPOSE: To evaluate choroidal thickness and choroidal vascular index (CVI) in healthy women using the combined oral contraceptive pill (COCp).

METHODS: This prospective study included 30 women using COCp (3 mg drospirenone/0.03 mg ethinylestradiol) for contraception for at least 1 year and 30 healthy women who did not use COCp. Intraocular pressure (IOP), axial length (AL) and body mass index (BMI) values ​​of all participants were recorded. Subfoveal choroidal thickness (SCT) and choroidal thickness at 1500 micron distance in nasal and temporal regions (NCT, TCT) were measured through optical coherence tomography (OCT) images. Luminal, stromal and total choroidal area values were evaluated by binarization method. The ratio of the luminal choroidal area to the total choroidal area was determined as the CVI value.

RESULTS: There was no statistically significant difference in IOP and AL values between the two groups at no significant difference age and BMI index (p > 0.05, for all). SCT, NCT and TCT values were no significant difference in the two groups (p> 0.05, for all). Luminal and stromal choroidal area values ​​were found to be lower in the group using COCp (p = 0.01, p = 0.02 respectively). The CVI value was 62.1 ± 3.6% in the COCp group and 65.6 ± 4.3% in the control group. There was a significant difference between the two groups in terms of CVI value (p = 0.002).

CONCLUSION: To our knowledge, this is the first study to evaluate CVI in women using COCp, and CVI was found to be lower in individuals using COCp. Therefore, CVI can be used in the follow-up of possible ocular pathologies that may develop in individuals using COCp.

PMID:37437218 | DOI:10.1080/15569527.2023.2235429

J Am Coll Health. 2023 Jul 12:1-25. doi: 10.1080/07448481.2023.2227725. Online ahead of print.

ABSTRACT

Objective: Examine the impact of the campus food environment on postsecondary students’ dietary behaviors (e.g., dietary intake) and food purchasing. Participants: Students currently attending a postsecondary institution, all ages and geographic locations included. Methods: A systematic search from January 2000-October 2022 was conducted in six databases using postsecondary education, food environment, and diet related keywords. Results: In total, 25 quantitative and 10 qualitative studies were extracted. All quantitative studies that conducted statistical analyses (n = 15) reported a statistically significant relationship between the campus food environment and dietary intake, including both positive and negative effects. All qualitative studies (n = 10) discussed students’ experience of the campus food environment influencing their diet. Conclusions: This review found moderate evidence that the campus food environment has an impact on postsecondary students’ dietary behaviors. A campus environment that has healthy foods accessible, affordable, and acceptable for postsecondary students may have a beneficial impact on students’ dietary intake.

PMID:37437204 | DOI:10.1080/07448481.2023.2227725

Neural Comput. 2023 Jul 12:1-48. doi: 10.1162/neco_a_01601. Online ahead of print.

ABSTRACT

Understanding the effect of spike-timing-dependent plasticity (STDP) is key to elucidating how neural networks change over long timescales and to design interventions aimed at modulating such networks in neurological disorders. However, progress is restricted by the significant computational cost associated with simulating neural network models with STDP and by the lack of low-dimensional description that could provide analytical insights. Phase-difference-dependent plasticity (PDDP) rules approximate STDP in phase oscillator networks, which prescribe synaptic changes based on phase differences of neuron pairs rather than differences in spike timing. Here we construct mean-field approximations for phase oscillator networks with STDP to describe part of the phase space for this very high-dimensional system. We first show that single-harmonic PDDP rules can approximate a simple form of symmetric STDP, while multiharmonic rules are required to accurately approximate causal STDP. We then derive exact expressions for the evolution of the average PDDP coupling weight in terms of network synchrony. For adaptive networks of Kuramoto oscillators that form clusters, we formulate a family of low-dimensional descriptions based on the mean-field dynamics of each cluster and average coupling weights between and within clusters. Finally, we show that such a two-cluster mean-field model can be fitted to synthetic data to provide a low-dimensional approximation of a full adaptive network with symmetric STDP. Our framework represents a step toward a low-dimensional description of adaptive networks with STDP and could, for example inform the development of new therapies aimed at maximizing the long-lasting effects of brain stimulation.

PMID:37437202 | DOI:10.1162/neco_a_01601

J Am Coll Health. 2023 Jul 12:1-6. doi: 10.1080/07448481.2023.2230303. Online ahead of print.

ABSTRACT

Objective: To examine the interaction between high school (HS) sports participation and injury history with current moderate-to-vigorous physical activity (MVPA) among young adults. Participants: Participants (N = 236) were 18-25 years old, not currently injured, and reported no physical activity limitations. Methods: Participants completed online demographic, injury history, and physical activity surveys. A two-way analysis of covariance was used to test the interaction between HS athlete status and previous injury severity on current self-reported MVPA. Results: Participants were 22.2 ± 2.1 years, primarily White (81.8%) or Asian (6.4%), and female (77.5%). After including body mass index and race as covariates, there was a statistically significant interaction between HS athlete status and previous injury history such that current MVPA was higher among former HS athletes compared to HS recreational/nonathletes when individuals reported no injuries or mild injury severity. MVPA was similar across athlete status groups when participants reported high levels of injury severity. Conclusions: Future studies should examine whether young adults who have experienced multiple and/or severe injuries as competitive HS athletes have unique physical activity barriers.

PMID:37437201 | DOI:10.1080/07448481.2023.2230303

J Am Coll Health. 2023 Jul 12:1-10. doi: 10.1080/07448481.2023.2228425. Online ahead of print.

ABSTRACT

Objective: The purpose of this study was: (a) to determine COVID-19 vaccination rates among college students, (b) to assess what proportion of college students self-report currently or previously having COVID-19, and (c) to test theory of planned behavior (TPB)-based constructs in predicting the COVID-19 booster vaccination behavioral intentions. Methods: A non-experimental, cross-sectional study design was applied. Participants: The sample consisted of 288 college students ages 18 years and older. Results: The stepwise multiple regression revealed that attitude (β = .329; p < .001) and subjective norm (β = .244; p < .001) were statistically significant predictors of intention to receive the COVID-19 booster, accounting for 86.7% (Adjusted R² = .867, F (2, 204 = 673.002, p < .001) of the variance. Conclusions: College students are at high risk for more severe complications of COVID-19 infection due to low vaccination rates. The instrument designed for this study may be used to design TPB-based interventions to increase COVID-19 vaccination and booster intentions of college students.

PMID:37437193 | DOI:10.1080/07448481.2023.2228425

Epilepsia Open. 2023 Jul 12. doi: 10.1002/epi4.12790. Online ahead of print.

ABSTRACT

OBJECTIVE: Cortical stimulation is an important component of stereo-electroencephalography (SEEG). Despite this, there is currently no standardised approach and significant heterogeneity in the literature regarding cortical stimulation practices. Via an international survey of SEEG clinicians, we sought to examine the spectrum of cortical stimulation practices to reveal areas of consensus and variability.

METHODS: A 68-item questionnaire was developed to understand cortical stimulation practices including neurostimulation parameters, interpretation of epileptogenicity, functional and cognitive assessment and subsequent surgical decisions. Multiple recruitment pathways were pursued, with the questionnaire distributed directly to 183 clinicians.

RESULTS: Responses were received from 56 clinicians across 17 countries with experience ranging from 2 to 60 years (M=10.73, SD=9.44). Neurostimulation parameters varied considerably, with maximum current ranging from 3-10mA (M=5.33, SD=2.29) for 1Hz and 2-15mA (M=6.54, SD=3.68) for 50Hz stimulation. Charge density ranged from 8-200μC/cm² , with up to 43% of responders utilising charge densities higher than recommended upper safety limits i.e.55μC/cm² . North American responders reported statistically significant higher maximum current (p<0.001) for 1Hz stimulation and lower pulse width for 1Hz and 50Hz stimulation (p=0.008, p<0.001, respectively) compared to European responders. All clinicians evaluated language, speech, and motor function during cortical stimulation; in contrast, 42% assessed visuospatial or visual function, 29% memory, and 13% executive function. Striking differences were reported in approaches to assessment, classification of positive sites and surgical decisions guided by cortical stimulation. Patterns of consistency were observed for interpretation of the localising capacity of stimulated electroclinical seizures and auras, with habitual electroclinical seizures induced by 1Hz stimulation considered the most localising.

SIGNIFICANCE: SEEG cortical stimulation practices differed vastly across clinicians internationally, highlighting the need for consensus based clinical guidelines. In particular, an internationally standardised approach to assessment, classification, and functional prognostication will provide a common clinical and research framework for optimising outcomes for people with drug-resistant epilepsy.

PMID:37437189 | DOI:10.1002/epi4.12790

Environ Sci Technol. 2023 Jul 12. doi: 10.1021/acs.est.2c09264. Online ahead of print.

ABSTRACT

Particulate matter air pollution is a leading cause of global mortality, particularly in Asia and Africa. Addressing the high and wide-ranging air pollution levels requires ambient monitoring, but many low- and middle-income countries (LMICs) remain scarcely monitored. To address these data gaps, recent studies have utilized low-cost sensors. These sensors have varied performance, and little literature exists about sensor intercomparison in Africa. By colocating 2 QuantAQ Modulair-PM, 2 PurpleAir PA-II SD, and 16 Clarity Node-S Generation II monitors with a reference-grade Teledyne monitor in Accra, Ghana, we present the first intercomparisons of different brands of low-cost sensors in Africa, demonstrating that each type of low-cost sensor PM_2.5 is strongly correlated with reference PM_2.5, but biased high for ambient mixture of sources found in Accra. When compared to a reference monitor, the QuantAQ Modulair-PM has the lowest mean absolute error at 3.04 μg/m³, followed by PurpleAir PA-II (4.54 μg/m³) and Clarity Node-S (13.68 μg/m³). We also compare the usage of 4 statistical or machine learning models (Multiple Linear Regression, Random Forest, Gaussian Mixture Regression, and XGBoost) to correct low-cost sensors data, and find that XGBoost performs the best in testing (R²: 0.97, 0.94, 0.96; mean absolute error: 0.56, 0.80, and 0.68 μg/m³ for PurpleAir PA-II, Clarity Node-S, and Modulair-PM, respectively), but tree-based models do not perform well when correcting data outside the range of the colocation training. Therefore, we used Gaussian Mixture Regression to correct data from the network of 17 Clarity Node-S monitors deployed around Accra, Ghana, from 2018 to 2021. We find that the network daily average PM_2.5 concentration in Accra is 23.4 μg/m³, which is 1.6 times the World Health Organization Daily PM_2.5 guideline of 15 μg/m³. While this level is lower than those seen in some larger African cities (such as Kinshasa, Democratic Republic of the Congo), mitigation strategies should be developed soon to prevent further impairment to air quality as Accra, and Ghana as a whole, rapidly grow.

PMID:37437161 | DOI:10.1021/acs.est.2c09264