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A Climatological Study of the Relationship between Alpine Treeline and Thermally-driven Upslope Winds on Niwot Ridge, Colorado
Thermally-driven upslope winds are one of the many different wind patterns unique to mountainous terrain. While the general mechanics of these winds have been widely studied, there is a lack of information on how transitions in land cover influence these wind systems. Questions also remain about how these wind systems affect the biological functioning of mountain ecosystems. This two year measurement program indentified the upslope flow regimes common to the southeast face of Niwot Ridge, an east-west running ridge directly east of the Continental Divide in the Colorado Front Range. The study focused on the role that alpine treeline played in the generation of upslope winds, as well as whether the airmass composition of upslope versus downslope winds influenced the spatial distribution of alpine vegetation. Observations showed that thermally-driven upslope winds were most common in summer daytime hours. Differentiation between two different types of thermally-driven upslope winds, land cover-induced flow and anabatic flow, was done through an investigation of surface pressure and sensible heat flux at sites in the subalpine forest and alpine tundra. It was found that anabatic forces, not transitions in land cover from forest to tundra, were responsible for the generation of upslope winds on Niwot Ridge. Analyses on the composition of airmasses showed that upslope winds were generally cooler, more humid, and weaker in strength than downslope, westerly winds. These characteristics, combined with the higher frequency of upslope winds in the subalpine forest compared to the alpine tundra, suggested that upslope winds played an important role in the spatial distribution of vegetation in the alpine treeline ecotone
Space‐Scale Resolved Surface Fluxes Across a Heterogeneous, Mid‐Latitude Forested Landscape
The Earth\u27s surface is heterogeneous at multiple scales owing to spatial variability in various properties. The atmospheric responses to these heterogeneities through fluxes of energy, water, carbon, and other scalars are scale-dependent and nonlinear. Although these exchanges can be measured using the eddy covariance technique, widely used tower-based measurement approaches suffer from spectral losses in lower frequencies when using typical averaging times. However, spatially resolved measurements such as airborne eddy covariance measurements can detect such larger scale (meso-β, meso-γ) transport. To evaluate the prevalence and magnitude of these flux contributions, we applied wavelet analysis to airborne flux measurements over a heterogeneous mid-latitude forested landscape, interspersed with open water bodies and wetlands. The measurements were made during the Chequamegon Heterogeneous Ecosystem Energy-balance Study Enabled by a High-density Extensive Array of Detectors intensive field campaign. We ask, how do spatial scales of surface-atmosphere fluxes vary over heterogeneous surfaces across the day and across seasons? Measured fluxes were separated into smaller-scale turbulent and larger-scale mesoscale contributions. We found significant mesoscale contributions to sensible and latent heat fluxes through summer to autumn which would not be resolved in single-point tower measurements through traditional time-domain half-hourly Reynolds decomposition. We report scale-resolved flux transitions associated with seasonal and diurnal changes of the heterogeneous study domain. This study adds to our understanding of surface-atmospheric interactions over unstructured heterogeneities and can help inform multi-scale model-data integration of weather and climate models at a sub-grid scale
Does living in remote Australia lessen the impact of hardship on psychological distress?
AIMS
Rural and remote regions tend to be characterised by poorer socioeconomic conditions than urban areas, yet findings regarding differences in mental health between rural and urban areas have been inconsistent. This suggests that other features of these areas may reduce the impact of hardship on mental health. Little research has explored the relationship of financial hardship or deprivation with mental health across geographical areas.
METHODS
Data were analysed from a large longitudinal Australian study of the mental health of individuals living in regional and remote communities. Financial hardship was measured using items from previous Australian national population research, along with measures of psychological distress (Kessler-10), social networks/support and community characteristics/locality, including rurality/remoteness (inner regional; outer regional; remote/very remote). Multilevel logistic regression modelling was used to examine the relationship between hardship, locality and distress. Supplementary analysis was undertaken using Australian Household, Income and Labour Dynamics in Australia (HILDA) Survey data.
RESULTS
2161 respondents from the Australian Rural Mental Health Study (1879 households) completed a baseline survey with 26% from remote or very remote regions. A significant association was detected between the number of hardship items and psychological distress in regional areas. Living in a remote location was associated with a lower number of hardships, lower risk of any hardship and lower risk of reporting three of the seven individual hardship items. Increasing hardship was associated with no change in distress for those living in remote areas. Respondents from remote areas were more likely to report seeking help from welfare organisations than regional residents. Findings were confirmed with sensitivity tests, including replication with HILDA data, the use of alternative measures of socioeconomic circumstances and the application of different analytic methods.
CONCLUSIONS
Using a conventional and nationally used measure of financial hardship, people residing in the most remote regions reported fewer hardships than other rural residents. In contrast to other rural residents, and national population data, there was no association between such hardship and mental health among residents in remote areas. The findings suggest the need to reconsider the experience of financial hardship across localities and possible protective factors within remote regions that may mitigate the psychological impact of such hardshipThe Australian Rural Mental Health Study was funded
by the National Health and Medical Research Council
(Project Grant #401241, #631061); and also supported
by a Research Capacity Building Grant to the
Australian Rural Health Research Collaboration.
Tonelle Handley is supported by a postdoctoral fellowship from Australian Rotary Health, which is
acknowledged with gratitude
Reviews
Reviews of Workers' participation in decisions within undertakings, Industrial democracy in Europe, European industrial relations, Australian Unions: an Industrial relations perspective, The history of the A.C.T.U., Tackling discrimination at the workplace: an analysis of sex discrimination in Britain, Brothers: male dominance and technological change, Microelectronics and office jobs: women's employment, Women at Work, Married to the job: wives' incorporation in men's work, The future of work, Safety at work and the unions, The system of industrial relations in New Zealand, and The economics of Australian labour market
Modulating attentional load affects numerosity estimation: evidence against a pre-attentive subitizing mechanism
Traditionally, the visual enumeration of a small number of items (1 to about 4), referred to as subitizing, has been thought of as a parallel and pre-attentive process and functionally different from the serial attentive enumeration of larger numerosities. We tested this hypothesis by employing a dual task paradigm that systematically manipulated the attentional resources available to an enumeration task. Enumeration accuracy for small numerosities was severely decreased as more attentional resources were taken away from the numerical task, challenging the traditionally held notion of subitizing as a pre-attentive, capacity-independent process. Judgement of larger numerosities was also affected by dual task conditions and attentional load. These results challenge the proposal that small numerosities are enumerated by a mechanism separate from large numerosities and support the idea of a single, attention-demanding enumeration mechanism
Novel approach to observing system simulation experiments improves information gain of surface-atmosphere field measurements
The observing system design of multidisciplinary field measurements involves a variety of considerations on logistics, safety, and science objectives. Typically, this is done based on investigator intuition and designs of prior field measurements. However, there is potential for considerable increases in efficiency, safety, and scientific success by integrating numerical simulations in the design process. Here, we present a novel numerical simulation-environmental response function (NS-ERF) approach to observing system simulation experiments that aids surface-atmosphere synthesis at the interface of mesoscale and microscale meteorology. In a case study we demonstrate application of the NS-ERF approach to optimize the Chequamegon Heterogeneous Ecosystem Energy-balance Study Enabled by a High-density Extensive Array of Detectors 2019 (CHEESEHEAD19). During CHEESEHEAD19 pre-field simulation experiments, we considered the placement of 20 eddy covariance flux towers, operations for 72h of low-altitude flux aircraft measurements, and integration of various remote sensing data products. A 2h high-resolution large eddy simulation created a cloud-free virtual atmosphere for surface and meteorological conditions characteristic of the field campaign domain and period. To explore two specific design hypotheses we super-sampled this virtual atmosphere as observed by 13 different yet simultaneous observing system designs consisting of virtual ground, airborne, and satellite observations. We then analyzed these virtual observations through ERFs to yield an optimal aircraft flight strategy for augmenting a stratified random flux tower network in combination with satellite retrievals. We demonstrate how the novel NS-ERF approach doubled CHEESEHEAD19's potential to explore energy balance closure and spatial patterning science objectives while substantially simplifying logistics. Owing to its modular extensibility, NS-ERF lends itself to optimizing observing system designs also for natural climate solutions, emission inventory validation, urban air quality, industry leak detection, and multi-species applications, among other use cases. © 2021 Stefan Metzger et al
Superhumps in Cataclysmic Binaries. XXIII. V442 Ophiuchi and RX J1643.7+3402
We report the results of long observing campaigns on two novalike variables:
V442 Ophiuchi and RX J1643.7+3402. These stars have high-excitation spectra,
complex line profiles signifying mass loss at particular orbital phases, and
similar orbital periods (respectively 0.12433 and 0.12056 d). They are
well-credentialed members of the SW Sex class of cataclysmic variables. Their
light curves are also quite complex. V442 Oph shows periodic signals with
periods of 0.12090(8) and 4.37(15) days, and RX J1643.7+3402 shows similar
signals at 0.11696(8) d and 4.05(12) d. We interpret these short and long
periods respectively as a "negative superhump" and the wobble period of the
accretion disk. The superhump could then possibly arise from the heating of the
secondary (and structures fixed in the orbital frame) by inner-disk radiation,
which reaches the secondary relatively unimpeded since the disk is not
coplanar.
At higher frequencies, both stars show another type of variability:
quasi-periodic oscillations (QPOs) with a period near 1000 seconds. Underlying
these strong signals of low stability may be weak signals of higher stability.
Similar QPOs, and negative superhumps, are quite common features in SW Sex
stars. Both can in principle be explained by ascribing strong magnetism to the
white dwarf member of the binary; and we suggest that SW Sex stars are
borderline AM Herculis binaries, usually drowned by a high accretion rate. This
would provide an ancestor channel for AM Hers, whose origin is still
mysterious.Comment: PDF, 41 pages, 4 tables, 16 figures; accepted, in press, to appear
December 2002, PASP; more info at http://cba.phys.columbia.edu
Association of Triglyceride-Lowering LPL Variants and LDL-C-Lowering LDLR Variants With Risk of Coronary Heart Disease.
IMPORTANCE: Triglycerides and cholesterol are both carried in plasma by apolipoprotein B (ApoB)-containing lipoprotein particles. It is unknown whether lowering plasma triglyceride levels reduces the risk of cardiovascular events to the same extent as lowering low-density lipoprotein cholesterol (LDL-C) levels. OBJECTIVE: To compare the association of triglyceride-lowering variants in the lipoprotein lipase (LPL) gene and LDL-C-lowering variants in the LDL receptor gene (LDLR) with the risk of cardiovascular disease per unit change in ApoB. DESIGN, SETTING, AND PARTICIPANTS: Mendelian randomization analyses evaluating the associations of genetic scores composed of triglyceride-lowering variants in the LPL gene and LDL-C-lowering variants in the LDLR gene, respectively, with the risk of cardiovascular events among participants enrolled in 63 cohort or case-control studies conducted in North America or Europe between 1948 and 2017. EXPOSURES: Differences in plasma triglyceride, LDL-C, and ApoB levels associated with the LPL and LDLR genetic scores. MAIN OUTCOMES AND MEASURES: Odds ratio (OR) for coronary heart disease (CHD)-defined as coronary death, myocardial infarction, or coronary revascularization-per 10-mg/dL lower concentration of ApoB-containing lipoproteins. RESULTS: A total of 654 783 participants, including 91 129 cases of CHD, were included (mean age, 62.7 years; 51.4% women). For each 10-mg/dL lower level of ApoB-containing lipoproteins, the LPL score was associated with 69.9-mg/dL (95% CI, 68.1-71.6; P = 7.1 × 10-1363) lower triglyceride levels and 0.7-mg/dL (95% CI, 0.03-1.4; P = .04) higher LDL-C levels; while the LDLR score was associated with 14.2-mg/dL (95% CI, 13.6-14.8; P = 1.4 × 10-465) lower LDL-C and 1.9-mg/dL (95% CI, 0.1-3.9; P = .04) lower triglyceride levels. Despite these differences in associated lipid levels, the LPL and LDLR scores were associated with similar lower risk of CHD per 10-mg/dL lower level of ApoB-containing lipoproteins (OR, 0.771 [95% CI, 0.741-0.802], P = 3.9 × 10-38 and OR, 0.773 [95% CI, 0.747-0.801], P = 1.1 × 10-46, respectively). In multivariable mendelian randomization analyses, the associations between triglyceride and LDL-C levels with the risk of CHD became null after adjusting for differences in ApoB (triglycerides: OR, 1.014 [95% CI, 0.965-1.065], P = .19; LDL-C: OR, 1.010 [95% CI, 0.967-1.055], P = .19; ApoB: OR, 0.761 [95% CI, 0.723-0.798], P = 7.51 × 10-20). CONCLUSIONS AND RELEVANCE: Triglyceride-lowering LPL variants and LDL-C-lowering LDLR variants were associated with similar lower risk of CHD per unit difference in ApoB. Therefore, the clinical benefit of lowering triglyceride and LDL-C levels may be proportional to the absolute change in ApoB.Dr. Ference is supported by the National Institute for Health Research Cambridge Biomedical Research Centre at the Cambridge University Hospitals NHS Foundation Trust. Dr. Clare Oliver-Williams is supported by Homerton College, University of Cambridge. Dr. Butterworth is supported by the European Research Council. Dr Danesh is supported by the Medical Research Council, British Heart Foundation, and the National Institute for Health Research
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