Frailty and Respiratory Impairment in Older Persons Vaz Fragoso, Carlos A., MD; Enright, Paul L., MD; McAvay, Gail, PhD ...
The American journal of medicine,
2012, 2012-Jan, 2012-01-00, 20120101, Volume:
125, Issue:
1
Journal Article
Peer reviewed
Open access
Abstract Background Among older persons, the association between frailty and spirometry-confirmed respiratory impairment has not been evaluated yet. Methods By using data on white participants aged ...65 to 80 years (Cardiovascular Health Study, N = 3578), we evaluated cross-sectional and longitudinal associations between frailty and respiratory impairment, including their combined effect on mortality. Baseline assessments included frailty status (Fried phenotype: non-frail, pre-frail, and frail) and spirometry. Outcomes included development of frailty features (pre-frail or frail) at year 3 and respiratory impairment (airflow limitation or restrictive pattern) at year 4, and death (median follow-up, 13.2 years). Results At baseline, 48.3% of participants were pre-frail, 5.8% of participants were frail, 13.8% of participants had airflow limitation, and 9.3% of participants had restrictive pattern; 46.1% of participants subsequently died. At baseline, pre-frail and frail were cross-sectionally associated with airflow limitation (adjusted odds ratio OR, 1.62; 95% confidence interval CI, 1.29-2.04 and adjusted OR 1.88; 95% CI, 1.15-3.09) and restrictive pattern (adjusted OR, 1.80; 95% CI, 1.37-2.36 and adjusted OR, 3.05; 95% CI, 1.91-4.88), respectively. Longitudinally, participants with baseline frailty features had an increased likelihood of developing respiratory impairment (adjusted OR, 1.42; 95% CI, 1.11-1.82). Conversely, participants with baseline respiratory impairment had an increased likelihood of developing frailty features (adjusted OR, 1.58; 95% CI, 1.17-2.13). Mortality was highest among participants who were frail and had respiratory impairment (adjusted hazard ratio, 3.91; 95% CI, 2.93-5.22), compared with those who were non-frail and had no respiratory impairment. Conclusion Frailty and respiratory impairment are strongly associated with one another and substantially increase the risk of death when both are present. Establishing these associations may inform interventions designed to reverse or prevent the progression of either condition and to reduce adverse outcomes.
•A new generation expansion planning (GEP) model is presented.•The model formulation and results are compared to a traditional GEP model.•Short term impacts of variable renewable energy sources (RES) ...need to be considered on GEP.•High RES reliance will increase the system’s sensitivity to resources seasonality.•Assuming average operating conditions in traditional GEP can result on sub-optimal solutions.
This study presents a new generation expansion planning (GEP) incorporating the effects of renewables variable generation on thermal power plants efficiency. An hourly unit commitment problem was integrated in the GEP problem with the overall goal of supporting the selection of future mixes of power plants through long term planning. The problem resulted in a binary mixed integer non-linear cost optimization model. The model application was demonstrated for the design of electricity plans for a 10year planning period under different CO2 assumptions for a thermal, hydroelectric and wind power system. The results were compared with the ones obtained using a traditional GEP model, which assumed average operating conditions for thermal power plants. The scenario analysis shows that the impact of renewables variability on the performance of thermal power plants and on the generation expansion planning is non-negligible. The results suggest that assuming average operating conditions can result on the underestimation of the system costs which highlights the importance of the proposed integrated model to strategic decision making.
A number of first-order methods have been proposed for smooth multiobjective optimization for which some form of convergence to first-order criticality has been proved. Such convergence is global in ...the sense of being independent of the starting point. In this paper, we analyse the rate of convergence of gradient descent for smooth unconstrained multiobjective optimization, and we do it for non-convex, convex, and strongly convex vector functions. These global rates are shown to be the same as for gradient descent in single-objective optimization and correspond to appropriate worst-case complexity bounds. In the convex cases, the rates are given for implicit scalarizations of the problem vector function.
Facing the ever-growing demand for data storage will most probably require a new paradigm. Nanoscale magnetic skyrmions are anticipated to solve this issue as they are arguably the smallest spin ...textures in magnetic thin films in nature. We designed cobalt-based multilayered thin films in which the cobalt layer is sandwiched between two heavy metals and so provides additive interfacial Dzyaloshinskii-Moriya interactions (DMIs), which reach a value close to 2 mJ m(-2) in the case of the Ir|Co|Pt asymmetric multilayers. Using a magnetization-sensitive scanning X-ray transmission microscopy technique, we imaged small magnetic domains at very low fields in these multilayers. The study of their behaviour in a perpendicular magnetic field allows us to conclude that they are actually magnetic skyrmions stabilized by the large DMI. This discovery of stable sub-100 nm individual skyrmions at room temperature in a technologically relevant material opens the way for device applications in the near future.
Understanding the motion of magnetic skyrmions is essential if they are to be used as information carriers in devices. It is now shown that topological confinement endows the skyrmions with an ...unexpectedly large mass, which plays a key role in their dynamics.
The study of magnetoelectric materials has recently received renewed interest, in large part stimulated by breakthroughs in the controlled growth of complex materials and by the search for novel ...materials with functionalities suitable for next generation electronic devices. In this Progress Report, we present an overview of recent developments in the field, with emphasis on magnetoelectric coupling effects in complex oxide multiferroic composite materials.
Recent developments in the design of novel complex oxide multiferroic heterostructures—materials systems where magnetic and ferroelectric orders coexist, as the adjacent figure illustrates—are reviewed. By exploring proximity effects at the interface between different complex oxides, new couplings between the order parameters develop. This results in strong magnetoelectric couplings with added functionality, as required for next generation electronic devices.
Demand-Response (DR) has emerged as a valuable resource option for balancing electricity supply and demand. However, traditional power system models have neglected to include DR within long-term ...expansion problems. We can summarize our scientific contributions in the following aspects: (i) design of a new integrated co-optimization planning model for supply and demand coordination; (ii) assessment of the technical and economic impact of DR for systems with a high share of Renewable Energy Sources (RES) and (iii) proposal of the ‘opportunity cost’ concept for computing the price of not meeting the demand. Findings of this research support the hypothesis that DR scenarios reveal a high potential for delaying future investments in power capacity compared to scenario BAU (Business as Usual). However, it was found a limited potential of DR to integrate additional renewable plants. This research has provided further evidence concerning the potential of DR to decrease the levels of CO2 emissions that is strictly related to the reduced need for fossil fuel thermal power plants. Given the high RES share, uncertainties related to future weather conditions must be however highlighted. This study concludes on the importance of DR for power systems planning and lays the groundwork for future research.
•Design of a new integrated co-optimization planning model for supply and demand coordination.•Technical and economic DR potentials are assessed for a renewable-based energy system.•DR shows a high potential for reducing the need for additional thermal capacity.•Uncertainties related to future weather conditions might affect the cost-effective DR potential.•The spot prices might significantly affect the optimal scenarios with DR.
Anti-Inflammatory Effects of Peripheral Dopamine Moore, Shaun C; Vaz de Castro, Pedro A. S; Yaqub, Daniel ...
International journal of molecular sciences,
09/2023, Volume:
24, Issue:
18
Journal Article
Peer reviewed
Open access
Dopamine is synthesized in the nervous system where it acts as a neurotransmitter. Dopamine is also synthesized in a number of peripheral organs as well as in several types of cells and has ...organ-specific functions and, as demonstrated more recently, is involved in the regulation of the immune response and inflammatory reaction. In particular, the renal dopaminergic system is very important in the regulation of sodium transport and blood pressure and is particularly sensitive to stimuli that cause oxidative stress and inflammation. This review is focused on how dopamine is synthesized in organs and tissues and the mechanisms by which dopamine and its receptors exert their effects on the inflammatory response.
Background.
Older persons have an increased risk of developing respiratory impairment because the aging lung is likely to have experienced exposures to environmental toxins as well as reductions in ...physiological capacity.
Methods.
Systematic review of risk factors and measures of pulmonary function that are most often considered when defining respiratory impairment in aging populations.
Results.
Across the adult life span, there are frequent exposures to environmental toxins, including tobacco smoke, respiratory infections, air pollution, and occupational dusts. Concurrently, there are reductions in physiological capacity that may adversely affect ventilatory control, respiratory muscle strength, respiratory mechanics, and gas exchange. Recent work has provided a strong rationale for defining respiratory impairment as an age-adjusted reduction in spirometric measures of pulmonary function that are independently associated with adverse health outcomes. Specifically, establishing respiratory impairment based on spirometric Z-scores has been shown to be strongly associated with respiratory symptoms, frailty, and mortality. Alternatively, respiratory impairment may be defined by the peak expiratory flow, as measured by a peak flow meter. The peak expiratory flow, when expressed as a Z-score, has been shown to be strongly associated with disability and mortality. However, because it has a reduced diagnostic accuracy, peak expiratory flow should only define respiratory impairment when spirometry is not readily available or an older person cannot adequately perform spirometry.
Conclusions.
Aging is associated with an increased risk of developing respiratory impairment, which is best defined by spirometric Z-scores. Alternatively, in selected cases, respiratory impairment may be defined by peak expiratory flow, also expressed as a Z-score.
Exoplanet detections have revolutionized astronomy, offering new insights into solar system architecture and planet demographics. While nearly 1,900 exoplanets have now been discovered and confirmed, ...none are still in the process of formation. Transition disks, protoplanetary disks with inner clearings best explained by the influence of accreting planets, are natural laboratories for the study of planet formation. Some transition disks show evidence for the presence of young planets in the form of disk asymmetries or infrared sources detected within their clearings, as in the case of LkCa 15 (refs 8, 9). Attempts to observe directly signatures of accretion onto protoplanets have hitherto proven unsuccessful. Here we report adaptive optics observations of LkCa 15 that probe within the disk clearing. With accurate source positions over multiple epochs spanning 2009-2015, we infer the presence of multiple companions on Keplerian orbits. We directly detect Hα emission from the innermost companion, LkCa 15 b, evincing hot (about 10,000 kelvin) gas falling deep into the potential well of an accreting protoplanet.
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