4,324 research outputs found
Observation of b symmetry vibrational levels of the SO \tilde{\mbox{C}} B state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants
The B state of SO has a double-minimum
potential in the antisymmetric stretch coordinate, such that the minimum energy
geometry has nonequivalent SO bond lengths. However, low-lying levels with odd
quanta of antisymmetric stretch (b vibrational symmetry) have not
previously been observed because transitions into these levels from the
zero-point level of the state are vibronically forbidden.
We use IR-UV double resonance to observe the b vibrational levels of the
state below 1600 cm of vibrational excitation. This
enables a direct characterization of the vibrational level staggering that
results from the double-minimum potential. In addition, it allows us to
deperturb the strong -axis Coriolis interactions between levels of a and
b vibrational symmetry, and to determine accurately the vibrational
dependence of the rotational constants in the distorted
electronic state
Management Forecasts in Crowded Sectors
This paper documents a dual role for disclosure. In addition to the traditional role of alleviating information asymmetry, firms are motivated to disclose to attract investors’ limited resources and order flow away from other firms (Fishman and Hagerty, 1989). In periods when firms returns comove more with their sector's returns and thus face more competition for investors, they issue more guidance, especially capex guidance. The effect of firm-sector comovement ("sector crowdedness") on guidance increases with fiercer competition for investors. Guidance increases liquidity and price efficiency (measured as investment sensitivity to price), but the impact of guidance decreases in sector crowdedness, consistent with the proposition that more disclosure in the crowded sectors is investor-seeking rather than precision increasing. Although the impact of guidance on investment-price sensitivity is lower in more crowded sectors, the effect is still positive, suggesting that firms can improve price efficiency by issuing guidance to attract informed investors to the firm
Perceptions of health risk among parents of overweight children: a cross-sectional study within a cohort.
OBJECTIVE: To identify the socio-demographic and behavioural characteristics associated with perceptions of weight-related health risk among the parents of overweight children. METHODS: Baseline data from a cohort of parents of children aged 4-11 years in five areas in England in 2010-2011 were analysed; the sample was restricted to parents of overweight children (body mass index ≥ 91(st) centile of UK 1990 reference; n=579). Associations between respondent characteristics and parental perception of health risk associated with their child's weight were examined using logistic regression analyses. RESULTS: Most parents (79%) did not perceive their child's weight to be a health risk. Perception of a health risk was associated with recognition of the child's overweight status (OR 10.59, 95% CI 5.51 to 20.34), having an obese child (OR 4.21, 95% CI 2.28 to 7.77), and having an older child (OR 2.67, 95% CI 1.32 to 5.41). However, 41% of parents who considered their child to be overweight did not perceive a health risk. CONCLUSIONS: Parents that recognise their child's overweight status, and the parents of obese and older children, are more likely to perceive a risk. However, many parents that acknowledge their child is overweight do not perceive a related health risk
Tgif1 Counterbalances The Activity Of Core Pluripotency Factors In Mouse Embryonic Stem Cells
Core pluripotency factors, such as Oct4, Sox2, and Nanog, play important roles in maintaining embryonic stem cell (ESC) identity by autoregulatory feedforward loops. Nevertheless, the mechanism that provides precise control of the levels of the ESC core factors without indefinite amplification has remained elusive. Here, we report the direct repression of core pluripotency factors by Tgif1, a previously known terminal repressor of TGF beta/activin/nodal signaling. Overexpression of Tgif1 reduces the levels of ESC core factors, whereas its depletion leads to the induction of the pluripotency factors. We confirm the existence of physical associations between Tgif1 and Oct4, Nanog, and HDAC1/2 and further show the level of Tgif1 is not significantly altered by treatment with an activator/inhibitor of the TGF beta/activin/nodal signaling. Collectively, our findings establish Tgif1 as an integral member of the core regulatory circuitry of mouse ESCs that counterbalances the levels of the core pluripotency factors in a TGF beta/activin/nodal-independent manner.Cancer Prevention Research Institute of Texas (CPRIT) R1106Molecular Bioscience
The importance of broadband for socio-economic development: a perspective from rural Australia
Advanced connectivity offers rural communities prospects for socio-economic development. Despite Australia’s national broadband infrastructure plans, inferior availability and quality of rural Internet connections remain persistent issues. This article examines the impact of limited connectivity on rural socio-economic opportunities, drawing from the views of twelve citizens from the Boorowa local government area in New South Wales. The available fixed wireless and satellite connections in Boorowa are slow and unreliable, and remote regions in the municipality are still without any Internet access. Participants identified four key areas in their everyday lives that are impacted by insufficient connectivity: business development, education, emergency communication, and health. Rural citizens often already face challenges in these areas, and infrastructure advancements in urban spaces can exacerbate rural-urban disparities. Participants’ comments demonstrated apprehension that failure to improve connectivity would result in adverse long-term consequences for the municipality. This article suggests that current broadband policy frameworks require strategic adaptations to account for the socio-economic and geographic contexts of rural communities. In order to narrow Australia’s rural-urban digital divide, infrastructure developments should be prioritised in the most underserved regions
Digital biomarkers of physical frailty and frailty phenotypes using sensor-based physical activity and machine learning
Remote monitoring of physical frailty is important to personalize care for slowing down the frailty process and/or for the healthy recovery of older adults following acute or chronic stressors. Taking the Fried frailty criteria as a reference to determine physical frailty and frailty phenotypes (slowness, weakness, exhaustion, inactivity), this study aimed to explore the benefit of machine learning to determine the least number of digital biomarkers of physical frailty measurable from a pendant sensor during activities of daily living. Two hundred and fifty-nine older adults were classified into robust or pre-frail/frail groups based on the physical frailty assessments by the Fried frailty criteria. All participants wore a pendant sensor at the sternum level for 48 h. Of seventeen sensor-derived features extracted from a pendant sensor, fourteen significant features were used for machine learning based on logistic regression modeling and a recursive feature elimination technique incorporating bootstrapping. The combination of percentage time standing, percentage time walking, walking cadence, and longest walking bout were identified as optimal digital biomarkers of physical frailty and frailty phenotypes. These findings suggest that a combination of sensor-measured exhaustion, inactivity, and speed have potential to screen and monitor people for physical frailty and frailty phenotypes
The influence of acetaminophen on sprint interval treadmill running: a randomized crossover trial
Although considerable research concerning the efficacy of analgesics in sport exists, there is a paucity of data concerning effects of acute acetaminophen (ACT) ingestion on sprint interval running exercise. This investigation concerned the effect of acute ACT ingestion on eight 30 s maximal treadmill sprints on a non-motorized treadmill, interspersed with two minutes rest in males (n=8, age 26±3 years, height 174±7 cm, mass 71±8 kg) in a placebo-controlled, randomized crossover design. A time x condition repeated measures analysis of variance (ANOVA) determined ACT ingestion did not influence mean power output, peak power output, peak vertical ground reaction force, peak oxygen uptake, or total distance completed (p>.05). Perceived pain was reduced by 8-15% during the final three sprints following ACT ingestion (p<.05). Data presented here suggest ACT may reduce exercise-induced pain during the latter stages of sprint interval treadmill running, without influencing performance
XIAP upregulates expression of HIF target genes by targeting HIF1 alpha for Lys(63)-linked polyubiquitination
The cellular response to hypoxia is characterised by a switch in the transcriptional program, mediated predominantly by the hypoxia inducible factor family of transcription factors (HIF). Regulation of HIF1 is primarily controlled by post-translational modification of the HIF1α subunit, which can alter its stability and/or activity. This study identifies an unanticipated role for the X-linked inhibitor of apoptosis (XIAP) protein as a regulator of Lys63-linked polyubiquitination of HIF1α. Lys63-linked ubiquitination of HIF1α by XIAP is dependent on the activity of E2 ubiquitin conjugating enzyme Ubc13. We find that XIAP and Ubc13 dependent Lys63-linked polyubiquitination promotes HIF1α nuclear retention leading to an increase in the expression of HIF1 responsive genes. Inhibition of the Lys63-linked polyubiquitination pathway leads to reduced levels of nuclear HIF1α, promoter occupancy, HIF-dependent gene expression and cell viability. Our data reveals an additional and significant level of control of the HIF1 by XIAP, with important implications in understanding the role of HIF1 and XIAP in human disease
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