735 research outputs found

    Double resonant absorption measurement of acetylene symmetric vibrational states probed with cavity ring down spectroscopy

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    A novel mid-infrared/near-infrared double resonant absorption setup for studying infrared-inactive vibrational states is presented. A strong vibrational transition in the mid-infrared region is excited using an idler beam from a singly resonant continuous-wave optical parametric oscillator, to populate an intermediate vibrational state. High output power of the optical parametric oscillator and the strength of the mid-infrared transition result in efficient population transfer to the intermediate state, which allows measuring secondary transitions from this state with a high signal-to-noise ratio. A secondary, near-infrared transition from the intermediate state is probed using cavity ring down spectroscopy, which provides high sensitivity in this wavelength region. Due to the narrow linewidths of the excitation sources, the rovibrational lines of the secondary transition are measured with sub-Doppler resolution. The setup is used to access a previously unreported symmetric vibrational state of acetylene, ν1+ν2+ν3+ν41+ν51\nu_1+\nu_2+\nu_3+\nu_4^1+\nu_5^{-1} in the normal mode notation. Single-photon transitions to this state from the vibrational ground state are forbidden. Ten lines of the newly measured state are observed and fitted with the linear least-squares method to extract the band parameters. The vibrational term value was measured to be at 9775.0018(45) cm1\text{cm}^{-1}, the rotational parameter BB was 1.162222 cm1\text{cm}^{-1}, and the quartic centrifugal distortion parameter DD was 3.998(62)×106cm1\times 10^{-6} \text{cm}^{-1}, where the numbers in the parenthesis are one-standard errors in the least significant digits

    Effectiveness of legislative changes obligating notification of prolonged sickness absence and assessment of remaining work ability on return to work and work participation : a natural experiment in Finland

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    Objectives Policies have been introduced to reduce sickness absence, but their effectiveness is largely unknown. In a natural experiment, we examined effects of legislative changes on return to work and work participation. Methods The source population consisted of up to 72164 Finnish public sector employees with a permanent job contract in 2008-2011 (before) and in 2013-2014 (after). We used employees with a continuous sickness absence of at least 30 calendar-days (n=5708-6393), 60 compensated days (n=1481-1655) and 90 compensated days (n=766-932). We examined sustainable return to work (a minimum of 28 consecutive working days) with survival analysis as well as monthly work participation after a sickness absence, and annual gain in work participation after the intervention, using trajectory analyses. Results Sustainable return to work after 60days of sickness absence occurred earlier after the legislative changes (p value 0.017), although the effect reduced towards the end of the follow-up. There were no differences in return to work after a 30 or 90days of sickness absence. The largest annual gain, postintervention versus preintervention, in monthly work participation was observed among employees with 60days of sickness absence and was 230.9 person-years/10000 employees. The corresponding annual gains among those with 30days and 90days of sickness absence were 51.8 and 39.6, respectively. Conclusions Our findings suggest that the legislative changes, obligating early notification of prolonged sickness absences as well as assessment of remaining work ability and possibilities to continue working, may enhance sustainable return to work in the short term. Other measures will be needed to enhance work participation, especially in the long term.Peer reviewe

    Change in neighborhood disadvantage and change in smoking behaviors in adults: a longitudinal, within-individual study

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    BACKGROUND: Evidence for an association between neighborhood disadvantage and smoking is mixed and mainly based on cross-sectional studies. To shed light on the causality of this association we examined whether change in neighborhood socioeconomic disadvantage is associated with within-individual change in smoking behaviors. METHODS: The study population comprised participants of the Finnish Public Sector study who reported a change in their smoking behavior between surveys in 2008/09 and 2012/13. We linked participants' residential addresses to a total population database on neighborhood disadvantage with 250 × 250m resolution. The outcome variables were changes in smoking status (being a smoker vs. not) as well as the intensity (heavy/moderate vs. light smoker). We used longitudinal case-crossover design, a method that accounts for time-invariant confounders by design. We adjusted models for time-varying covariates. RESULTS: Of the 3443 participants, 1714 quit while 967 began to smoke between surveys. Smoking intensity increased among 398 and decreased among 364 participants. The level of neighborhood disadvantage changed for 1078 participants because they moved residence. Increased disadvantage was associated with increased odds of being a smoker (odds ratio (OR) of taking up smoking 1.23 (95% CI 1.04-1.47) per 1 standard deviation (SD) increase in standardized national disadvantage score). OR for being a heavy/moderate (vs. light) smoker was 1.14 (95% CI 0.85-1.52) when disadvantage increased by 1 SD. CONCLUSIONS: These within-individual results link an increase in neighborhood socioeconomic disadvantage, due to move in residence, with subsequent smoking behaviors

    Shift work, work time control, and informal caregiving as risk factors for sleep disturbances in an ageing municipal workforce

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    Objectives This study aimed to examine the contribution of shift work, work time control (WTC) and informal caregiving, separately and in combination, to sleep disturbances in ageing employees. Methods Survey data were obtained from two prospective cohort studies with repeated measurements of working conditions, informal caregiving, and sleep disturbances. We used fixed-effect conditional logistic regression analysis to examine whether within-individual changes in shift work, WTC and informal caregiving were associated with changes in sleep. Secondary analyses included between-individuals comparison using standard logistic regression models. Results from the two cohorts were pooled using meta-analysis. Results Low WTC and informal caregiving were associated with sleep disturbances in within-individual analyses [odds ratios (OR) ranging between 1.13 (95% confidence interval 1.01-1.27) and 1.48 (95% CI 1.29-1.68)] and in between-individuals analyses [OR 1.14 (95% CI 1.03-1.26) to 1.33 (1.19-1.49)]. Shift work alone was not associated with sleep disturbances, but accumulated exposure to shift work, low WTC and informal caregiving was associated with higher risk of sleep disturbances (OR range 1.21-1.76). For some of the sleep outcomes, informal caregiving was related to a higher risk of sleep disturbances when WTC was low and a lower risk when WTC was high. Conclusions Informal caregiving and low WTC are associated with risk of sleep disturbances among ageing employees. The findings also suggest that low WTC in combination with informal caregiving may increase the risk of sleep disturbances whereas high WTC may alleviate the adverse impact of informal caregiving on sleep

    Change in Job Strain as a Predictor of Change in Insomnia Symptoms: Analyzing Observational Data as a Non-randomized Pseudo-Trial

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    Study objectives: To examine whether change in job strain leads to change in insomnia symptoms. Methods: Among 24873 adults (82% women, mean age 44 years) who participated in a minimum of three consecutive study waves (2000–2012), job strain was assessed at the first and second wave and insomnia symptoms at all three waves. We analyzed observational data as a “pseudo-trial” including participants with no job strain in the first wave and no insomnia symptoms in the first and second wave (n = 7354) to examine whether the onset of job strain between the first and second waves predicted the onset of insomnia symptoms in the third wave. We used a corresponding approach, including those with job strain in the first wave and insomnia symptoms in the first and second wave (n = 2332), to examine whether the disappearance of job strain between the first two waves predicted remission of insomnia symptoms in the third wave. Results: The onset of job strain predicted the onset of subsequent insomnia symptoms after adjustment for sex, age, marital status, education, smoking, physical activity, alcohol consumption, body mass index, and comorbidities (odds ratio compared to no onset of job strain 1.32, 95% CI 1.16–1.51). The disappearance of job strain was associated with lower odds of repeated insomnia symptoms (odds ratio compared to no disappearance of job strain 0.78, 95% CI 0.65–0.94). Further adjustment for shift work or sleep apnea did not change these associations. Conclusions: These results suggest that job strain is a modifiable risk factor for insomnia symptoms

    Changes in physical activity by context and residential greenness among recent retirees : Longitudinal GPS and accelerometer study

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    This study examined the changes in accelerometer-measured physical activity by GPS-measured contexts among Finnish retirees (n = 45 (537 measurement days)) participating in a physical activity intervention. We also assessed whether residential greenness, measured with Normalized Difference Vegetation Index, moderated the changes. Moderate-to-vigorous physical activity (MVPA) increased at home by 7 min/day, (P < 0.001) and during active travel by 5 min/day (P = 0.03). The participants with the highest vs. lowest greenness had 25 min/ day greater increase in MVPA over the follow-up (P for Time*Greenness interaction = 0.04). In conclusion, retirees participating in the intervention increased their MVPA both at home and in active travel, and more so if they lived in a greener area.Peer reviewe

    Cantilever-Enhanced Photoacoustic Spectroscopy of Radioactive Methane

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    We report the first high-resolution spectroscopy study of radiocarbon methane, 14CH4. Several absorption lines of the fundamental vibrational band v3 were measured using a continuous-wave mid-infrared optical parametric oscillator with cantilever-enhanced photoacoustic spectroscopy. © 2020 OSA.Peer reviewe

    Association Between Distance From Home to Tobacco Outlet and Smoking Cessation and Relapse

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    IMPORTANCE: Reduced availability of tobacco outlets is hypothesized to reduce smoking, but longitudinal evidence on this issue is scarce. OBJECTIVE: To examine whether changes in distance from home to tobacco outlet are associated with changes in smoking behaviors. DESIGN, SETTING, AND PARTICIPANTS: The data from 2 prospective cohort studies included geocoded residential addresses, addresses of tobacco outlets, and responses to smoking surveys in 2008 and 2012 (the Finnish Public Sector [FPS] study, n = 53 755) or 2003 and 2012 (the Health and Social Support [HeSSup] study, n = 11 924). All participants were smokers or ex-smokers at baseline. We used logistic regression in between-individual analyses and conditional logistic regression in case-crossover design analyses to examine change in walking distance from home to the nearest tobacco outlet as a predictor of quitting smoking in smokers and smoking relapse in ex-smokers. Study-specific estimates were pooled using fixed-effect meta-analysis. EXPOSURES: Walking distance from home to the nearest tobacco outlet. MAIN OUTCOMES AND MEASURES: Quitting smoking and smoking relapse as indicated by self-reported current and previous smoking at baseline and follow-up. RESULTS: Overall, 20 729 men and women (age range 18-75 years) were recruited. Of the 6259 and 2090 baseline current smokers, 1744 (28%) and 818 (39%) quit, and of the 8959 and 3421 baseline ex-smokers, 617 (7%) and 205 (6%) relapsed in the FPS and HeSSup studies, respectively. Among the baseline smokers, a 500-m increase in distance from home to the nearest tobacco outlet was associated with a 16% increase in odds of quitting smoking in the between-individual analysis (pooled odds ratio, 1.16; 95% CI, 1.05-1.28) and 57% increase in within-individual analysis (pooled odds ratio, 1.57; 95% CI, 1.32-1.86), after adjusting for changes in self-reported marital and working status, substantial worsening of financial situation, illness in the family, and own health status. Increase in distance to the nearest tobacco outlet was not associated with smoking relapse among the ex-smokers. CONCLUSIONS AND RELEVANCE: These data suggest that increase in distance from home to the nearest tobacco outlet may increase quitting among smokers. No effect of change in distance on relapse in ex-smokers was observed

    Infrared Excess in the Be Star Delta Scorpii

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    We present infrared photometric observations of the Be binary system delta Scorpii obtained in 2006. The J,H and K magnitudes are the same within the errors compared to observations taken 10 months earlier. We derive the infrared excess from the observation and compare this to the color excess predicted by a radiative equilibrium model of the primary star and its circumstellar disk. We use a non-LTE computational code to model the gaseous envelope concentrated in the star's equatorial plane and calculate the expected spectral energy distribution and Halpha emission profile of the star with its circumstellar disk. Using the observed infrared excess of delta Sco, as well as Halpha spectroscopy bracketing the IR observations in time, we place constraints on the radial density distribution in the circumstellar disk. Because the disk exhibits variability in its density distribution, this work will be helpful in understanding its dynamics.Comment: 12 pages, 14 figures, to be published in PASP May 200

    Changes in Smoking During Retirement Transition: A Longitudinal Cohort Study

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    AIMS: We examined the effect of retirement transition on changes in smoking, identified trajectories of smoking around the retirement transition, and investigated factors predicting the membership in the trajectories. METHODS: This longitudinal cohort study included 1,432 current or former smokers who entered into statutory retirement in 2000-2011 and who filled out two to four questionnaires sent at four-year intervals. Effect of retirement on smoking was analysed as a non-randomized pseudo-trial in which we compared the likelihood of quitting and relapsing smoking between two subsequent survey waves among those who retired and did not retire. We used latent class analysis to identify trajectories of smoking status and smoking intensity (low: <10 cigarettes/day or high: ⩾10 cigarettes/day), and multinomial logistic regression models to assess pre-retirement factors associated with smoking trajectories. RESULTS: Retirement transition was associated with 1.7-fold odds of quitting smoking (95% confidence intervals 1.3-2.2) compared with no retirement transition. We identified three smoking status trajectories: 'sustained non-smoking' (61% of the participants), 'sustained smoking' (23%) and 'decreasing smoking' (16%). For 489 baseline smokers, we identified three smoking intensity trajectories: 'sustained high intensity smoking' (32% of the participants), 'sustained low intensity smoking' (32%) and 'decreasing high intensity smoking' (35%). Living outside an inner urban area predicted membership in the 'decreasing smoking' versus 'sustained smoking' trajectory. CONCLUSIONS: Smokers are more likely to quit smoking during transition to retirement than before or after it. Characteristics of the smoking environment may affect smoking behaviour around retirement
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