494 research outputs found
Erratum: Is it possible to infer the equation of state of a mixture of hard discs from that of the one-component system?
The numerical values in the sixth and seventh columns of table 1 of the paper
Molec. Phys., 1999, 96, 1185-1188 are not correct. Consequently, some of the
comments made in the paper are wrong. The corrected version of table 1 is
reprinted here and the results are briefly discussed.Comment: 2 pages; Erratum to Molec. Phys., 1999, 96, 1185-1188; to be
published in Molec. Phy
Dynamic concentration of motors in microtubule arrays
We present experimental and theoretical studies of the dynamics of molecular
motors in microtubule arrays and asters. By solving a convection-diffusion
equation we find that the density profile of motors in a two-dimensional aster
is characterized by continuously varying exponents. Simulations are used to
verify the assumptions of the continuum model. We observe the concentration
profiles of kinesin moving in quasi two-dimensional artificial asters by
fluorescent microscopy and compare with our theoretical results.Comment: 4pages, 4 figures revte
Modifiable Risk Factors Explain Socioeconomic Inequalities in Dementia Risk: Evidence from a Population-Based Prospective Cohort Study
BACKGROUND: Differences in dementia risk across the gradient of socioeconomic status (SES) exist, but their determinants are not well understood. OBJECTIVE: This study investigates whether health conditions and lifestyle-related risk factors explain the SES inequalities in dementia risk. METHODS: 6,346 participants from the English Longitudinal Study of Ageing were followed up from 2008/2009 until 2014/2015. We used Cox regression adjusted for age, gender, wealth/education, and clustering at the household level to examine the association between SES markers (wealth, education) and time to dementia in a structural equation model including potential mediation or effect modification by a weighted compound score of twelve modifiable risk and protective factors for dementia (‘LIfestyle for BRAin health’ (LIBRA) score). RESULTS: During a median follow-up of 6 years, 192 individuals (3.0%) developed dementia. LIBRA scores decreased with increasing wealth and higher educational level. A one-point increase in the LIBRA score was associated with a 13% increase in dementia risk (hazard ratio (HR) = 1.13, 95% confidence interval 1.07–1.19). Higher wealth was associated with a decreased dementia risk (HR = 0.58, 0.39–0.85). Mediation analysis showed that 52% of the risk difference between the highest and lowest wealth tertile was mediated by differences in LIBRA (indirect effect: HR = 0.75, 0.66–0.85). Education was not directly associated with dementia (HR = 1.05, 0.69–1.59), but was a distal risk factor for dementia by explaining differences in wealth and LIBRA scores (indirect effect high education: HR = 0.92, 0.88–0.95). CONCLUSION: Socioeconomic differences in dementia risk can be partly explained by differences in modifiable health conditions and lifestyle factors
Description and dosimetric verification of the PEREGRINE Monte Carlo dose calculation system for photon beams incident on a water phantom
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134919/1/mp1551.pd
Greater Blood Pressure Variability Is Associated With Lower Cognitive Performance:The Maastricht Study
An increasing number of individuals will face age-related cognitive difficulties because life expectancy has increased. It is, therefore, important to identify modifiable risk factors for cognitive impairment. Very short-term to mid-term blood pressure variability (BPV) may be such a factor because it may cause cerebral ischemia. To this end, we investigated whether greater systolic and diastolic BPV are cross-sectionally associated with memory function (n=1804), information processing speed (n=1793), and executive function (n=1780) in 40- to 75-year-old individuals from The Maastricht Study. A composite BPV-index was derived by standardizing within-visit, 24-hour, and 7-day BPV. We performed linear regression with adjustments for age, sex, educational level, 24-hour systolic or diastolic pressure, and cardiovascular risk factors. We found that a 1-SD greater systolic BPV was not associated with information processing speed (β [SD difference], -0.10; 95% CI, -0.14 to 0.06), or executive function (-0.09; 95% CI, -0.20 to 0.02) but was marginally associated with lower memory function (-0.11; 95% CI, -0.21 to 0.00). A 1-SD greater diastolic BPV was associated with lower information processing speed (-0.10; 95% CI, -0.20 to -0.00) and executive function (-0.12; 95% CI, -0.22 to -0.01) and marginally associated with lower memory function (-0.09; 95% CI, -0.20 to 0.01). These effects on cognitive performance are equivalent to ≈3 additional years of aging. In conclusion, greater very short-term to mid-term diastolic and, to a lesser extent, systolic BPV may be a modifiable risk factor for cognitive deterioration in 40- to 75-year-old, community-dwelling individuals
Effect of the Friendship Bench Intervention on Antiretroviral Therapy Outcomes and Mental Health Symptoms in Rural Zimbabwe: A Cluster Randomized Trial.
IMPORTANCE
Common mental disorders (CMD), which include depression and anxiety, are prevalent among people living with HIV and are associated with suboptimal antiretroviral therapy (ART) adherence.
OBJECTIVE
To assess the effect of a lay health worker-led psychological intervention on ART adherence, virologic suppression, and mental health symptoms.
DESIGN, SETTING, AND PARTICIPANTS
Open-label pragmatic cluster trial with 1:1 block randomization of 16 health facilities in rural Bikita, Zimbabwe. Recruitment occurred from October 2018 to December 2019, and participants were followed up for 12 months, ending in December 2020. Participants were adults aged 18 years and older, who spoke English or Shona, screened positive for CMD (Shona Symptoms Questionnaire [SSQ]-14 score ≥9), received first-line ART for 6 or more months, had no World Health Organization stage 4 disease, no psychosis, were not pregnant, and provided informed consent. Data were analyzed from March 2021 to February 2022.
INTERVENTION
The Friendship Bench, consisting of 6 lay health worker-led weekly problem-solving therapy sessions and optional peer-led group support.
MAIN OUTCOMES AND MEASURES
The primary outcome was mean adherence during 2 to 6 months of follow-up, and the secondary outcomes were mean adherence during 1 to 12 months of follow-up, change in SSQ-14 and Patient Health Questionnaire (PHQ-9) scores (3, 6, 9, and 12 months), and viral load suppression (6 and 12 months).
RESULTS
A total of 516 participants were recruited (244 in Friendship Bench and 272 in enhanced standard care facilities); 438 (84.9%) were female and the mean (SD) age was 45.6 (10.9) years. Mean (SD) adherence between 2 to 6 months was 89.9% (18.4%) in the Friendship Bench group and 87.2% (20.1%) in the control group. The intervention had no statistically significant effect on adherence between 2 to 6 months (unadjusted mean difference, 1.93 percentage points; 95% CI, -1.20 to 5.06 percentage points; P = .23), between months 1 to 12 (mean difference 0.79 percentage points; 95% CI, -2.14 to 3.71 percentage points; P = .60), or viral suppression. Declines in SSQ-14 scores from baseline to 3 months (difference, -1.65; 95% CI, -3.07 to -0.24), 6 months (difference, -1.57; 95% CI, -2.98 to -0.15), and 9 months (difference, -1.63; 95% CI, -3.05 to -0.22) were greater in the Friendship Bench than the standard care group (P < .05). There were no differences in the decline in the SSQ-14 scores from baseline to 12 months and in declines in PHQ-9 scores from baseline to 3, 6, 9, and 12 months.
CONCLUSIONS AND RELEVANCE
In this randomized trial of HIV-positive participants with CMD, the Friendship Bench intervention had no effect on adherence and viral suppression, possibly due to the absence of skill-based adherence training and a ceiling effect.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier: NCT03704805
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