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.
We present the results of 16 Swift-triggered Gamma-ray burst (GRB) follow-up observations taken with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) telescope array from 2007 ...January to 2009 June. The median energy threshold and response time of these observations were 260 GeV and 320 s, respectively. Observations had an average duration of 90 minutes. Each burst is analyzed independently in two modes: over the whole duration of the observations and again over a shorter timescale determined by the maximum VERITAS sensitivity to a burst with a t --1.5 time profile. This temporal model is characteristic of GRB afterglows with high-energy, long-lived emission that have been detected by the Large Area Telescope on board the Fermi satellite. No significant very high energy (VHE) gamma-ray emission was detected and upper limits above the VERITAS threshold energy are calculated. The VERITAS upper limits are corrected for gamma-ray extinction by the extragalactic background light and interpreted in the context of the keV emission detected by Swift. For some bursts the VHE emission must have less power than the keV emission, placing constraints on inverse Compton models of VHE emission.
Here, we report on the discovery of high-energy (HE; E > 0.1 GeV) and very high energy (VHE; E > 100 GeV) γ-ray emission from the high-frequency-peaked BL Lac object RBS 0413. VERITAS, a ground-based ...γ-ray observatory, detected VHE γ rays from RBS 0413 with a statistical significance of 5.5 standard deviations (σ) and a γ-ray flux of (1.5 ± 0.6stat ± 0.7syst) × 10–8 photons m–2 s–1 (~1% of the Crab Nebula flux) above 250 GeV. The observed spectrum can be described by a power law with a photon index of 3.18 ± 0.68stat ± 0.30syst. Contemporaneous observations with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope detected HE γ rays from RBS 0413 with a statistical significance of more than 9σ, a power-law photon index of 1.57 ± 0.12stat +0.11 – 0.12sys, and a γ-ray flux between 300 MeV and 300 GeV of (1.64 ± 0.43stat +0.31 – 0.22sys) × 10–5 photons m–2 s–1. We also present the results from Fermi-LAT and VERITAS, including a spectral energy distribution modeling of the γ-ray, quasi-simultaneous X-ray (Swift-XRT), ultraviolet (Swift-UVOT), and R-band optical (MDM) data. We finally find that, if conditions close to equipartition are required, both the combined synchrotron self-Compton/external-Compton and the lepto-hadronic models are preferred over a pure synchrotron self-Compton model.
Although boys are disproportionately affected by tics in Tourette syndrome (TS), this gender bias is attenuated in adulthood and a recent study has suggested that women may experience greater ...functional interference from tics than men. The authors assessed the gender distribution of adults in a tertiary University-based TS clinic population and the relative influence of gender and other variables on adult tic severity (YGTSS score) and psychosocial functioning (GAF score). We also determined retrospectively the influence of gender on change in global tic severity and overall TS impairment (YGTSS) since adolescence. Females were over-represented in relation to previously published epidemiologic surveys of both TS children and adults. Female gender was associated with a greater likelihood of tic worsening as opposed to tic improvement in adulthood; a greater likelihood of expansion as opposed to contraction of motor tic distribution; and with increased current motor tic severity and tic-related impairment. However, gender explained only a small percentage of the variance of the YGTSS global severity score and none of the variance of the GAF scale score. Psychosocial functioning was influenced most strongly by tic severity but also by a variety of comorbid neuropsychiatric disorders.
Students with autism spectrum disorder have been found to experience difficulty with reading comprehension despite intact decoding and word recognition. This identified need for targeted reading ...comprehension remediation results in a need for teachers to utilize research-based practices and to individualize instruction for students with autism spectrum disorder; however, teachers report a lack of access to such practices. This study utilized survey methodology to gather perceptions and experiences of teachers and to compare teacher preparedness to use effective instructional practices emerging from the extant research to teacher-reported effective practices in the classroom. Study findings, based on 112 participants, reveal a discrepancy between teacher-reported effective practices, and the practices identified as effective through research, indicating a research to practice gap. Implications for practice include professional development recommendations, and the need for increased communication between researchers and teachers.
The structure of the nitrogenase MoFe-protein from Azotobacter vinelandii has been refined to 2.0 Å resolution in two oxidation states. EPR studies on the crystals indicate that the structures ...correspond to the spectroscopically assigned oxidized (POX/MOX) and the native or dithionite-reduced (PN/MN) forms of the enzyme. Both MoFe-protein structures are essentially identical, with the exception of the P-cluster. The MoFe-protein P-cluster in each state is found to contain eight Fe and seven S atoms. Interconversion between the two redox states involves movement of two Fe atoms and an exchange of protein coordination for ligands supplied by a central S atom. In the oxidized POX state, the cluster is coordinated by the protein through six cysteine ligands, Ser-β188 Oγ, and the backbone amide of Cys-α88. In the native PN state, Ser-β188 Oγ and the amide N of Cys-α88 no longer coordinate the cluster due to movement of their coordinated Fe atoms toward the central sulfur. Consequently, this central sulfur adopts a distorted octahedral environment with six surrounding Fe atoms. A previously described model of the P-cluster containing 8Fe-8S likely reflects the inappropriate modeling of a single structure to a mixture of these two P-cluster redox states. These observed redox-mediated structural changes of the P-cluster suggest a role for this cluster in coupling electron transfer and proton transfer in nitrogenase.
Building on previous research in the area of written expression for individuals with ASD a research synthesis was conducted to identify (1) writing interventions that have been studied and their ...effect in improving writing skills of individuals with ASD, (2) intervention features that influence the writing skills of learners with ASD, and (3) the quality of the research. A total of 62 participants were represented across the 24 single case design studies meeting inclusion criteria. Nine interventions emerged with a majority focused on self-regulated strategy development. Effective interventions (PND above 70%) are reported, along with the emergent feature of “packages” using co-occurring combinations of visual, motivational, choice, technology, behavioral, peer, auditory, and tactile supports in conjunction with writing interventions.
Low back pain (LBP) is the most commonly reported musculoskeletal disorder among farmers. There is limited research regarding LBP among farmers in Ireland.
To explore attributed causes of LBP, ...investigate the relationship between LBP and personal and work-related factors and measure the impact of LBP.
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.
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.
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.
This study compared pronoun use in individuals with autism to their typically developing peers via meta-analysis and systematic review of 20 selected articles to examine differences in overall ...pronoun usage as well as in personal, ambiguous, possessive, reflexive, and clitic pronoun usage. Summary effects indicated significant differences between individuals with autism and their typically developing peers in the use of pronouns overall as well as in ambiguous, clitic, and reflexive pronoun usage, but not in personal and possessive pronoun usage. Results indicate wide variation in the way individuals with autism use pronouns, and individual outcomes appeared to be moderated by multiple factors, including cognitive ability, first language, and overall language development. Implications and recommendations for assessment and intervention practices are discussed.
Lay abstract
This research compared pronoun use in individuals with autism and typically developing peers. Meta-analysis and systematic review of 20 selected articles were used to determine whether significant differences existed in the use of pronouns overall as well as in personal, ambiguous, possessive, reflexive, and clitic pronoun usage. Summary effects indicated significant differences between individuals with autism and their typically developing peers in the use of pronouns overall as well as in ambiguous, clitic, and reflexive pronoun usage, but not in personal and possessive pronoun usage. Results indicate wide variation in the way individuals with autism use pronouns. Since individual outcomes appear to be moderated by multiple factors, including cognitive ability, first language, and overall language development, it is recommended these be considered in assessment and treatment.
PDF
