ABSTRACT
The sky is a natural heat sink that has been extensively used for passive radiative cooling of households. A lot of focus has been on maximizing the radiative cooling power of roof coating in the hot daytime using static, cooling-optimized material properties. However, the resultant overcooling in cold night or winter times exacerbates the heating cost, especially in climates where heating dominates energy consumption. We approached thermal regulation from an all-season perspective by developing a mechanically flexible coating that adapts its thermal emittance to different ambient temperatures. The fabricated temperature-adaptive radiative coating (TARC) optimally absorbs the solar energy and automatically switches thermal emittance from 0.20 for ambient temperatures lower than 15°C to 0.90 for temperatures above 30°C, driven by a photonically amplified metal-insulator transition. Simulations show that this system outperforms existing roof coatings for energy saving in most climates, especially those with substantial seasonal variations.
ABSTRACT
BACKGROUND: Low back pain (LBP) is the most commonly reported musculoskeletal disorder among farmers. There is limited research regarding LBP among farmers in Ireland. AIMS: To explore attributed causes of LBP, investigate the relationship between LBP and personal and work-related factors and measure the impact of LBP. METHODS: A questionnaire survey of Irish farmers was conducted on farmers from each of the main farm enterprise systems in Ireland. Data were analysed using chi-square tests, t-tests, Mann-Whitney tests and logistic regression models. RESULTS: There were 600 farmers included in the survey with 100 from each of the six main farm systems. Lifting/pulling/pushing was identified as the most commonly attributed cause of LBP. In the multiple regression analysis the variables found to be associated with LBP included farm size and self-rated health. The odds ratios (OR) of LBP were greater among operators of medium and large farms [(OR = 1.52; 95% confidence interval (CI): 1.04-2.22 and OR = 1.86; 95% CI: 1.16-3.98, respectively] compared with smaller farms (P < 0.05). Those who perceived health as 'good' (OR = 1.63; 95% CI: 1.14-2.33) by comparison with a rating of 'very good' had greater odds of LBP (P < 0.01). Some farmers changed work habits, sought help and needed time off work due to LBP. CONCLUSIONS: Lifting was identified as the main attributed cause for LBP. LBP leads to work disability that necessitated farmers changing work habits, getting help and needing time off work. In order to reduce LBP-related disability among farmers in the future, work practices involving lifting need to be further investigated.
Subject(s)
Agriculture , Low Back Pain/etiology , Movement , Occupational Diseases/etiology , Occupational Exposure/adverse effects , Physical Exertion , Work , Adolescent , Adult , Aged , Aged, 80 and over , Female , Health , Health Surveys , Humans , Ireland/epidemiology , Male , Middle Aged , Occupations , Odds Ratio , Surveys and Questionnaires , Workplace , Young AdultABSTRACT
We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga-electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega-electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star.
Subject(s)
Consumer Behavior , Medical Record Administrators , Public Relations , Communication , Humans , State Medicine , United KingdomABSTRACT
Given today's environment, the healthcare executive is faced with retooling his institution much like an industrial "turn-around" situation. The basic premise of this article is that the hospital's information resource should be a critical element in formulation, particularly as productivity improvement efforts are concerned. The article identifies specific methods for using both people and systems to maximize the benefits of information management.