This paper presents a succinct review of attempts in the literature to use game theory to model decision-making scenarios relevant to defence applications. Game theory has been proven as a very ...effective tool in modelling the decision-making processes of intelligent agents, entities, and players. It has been used to model scenarios from diverse fields such as economics, evolutionary biology, and computer science. In defence applications, there is often a need to model and predict the actions of hostile actors, and players who try to evade or out-smart each other. Modelling how the actions of competitive players shape the decision making of each other is the forte of game theory. In past decades, there have been several studies that applied different branches of game theory to model a range of defence-related scenarios. This paper provides a structured review of such attempts, and classifies existing literature in terms of the kind of warfare modelled, the types of games used, and the players involved. After careful selection, a total of 29 directly relevant papers are discussed and classified. In terms of the warfares modelled, we recognise that most papers that apply game theory in defence settings are concerned with Command and Control Warfare, and can be further classified into papers dealing with (i) Resource Allocation Warfare (ii) Information Warfare (iii) Weapons Control Warfare, and (iv) Adversary Monitoring Warfare. We also observe that most of the reviewed papers are concerned with sensing, tracking, and large sensor networks, and the studied problems have parallels in sensor network analysis in the civilian domain. In terms of the games used, we classify the reviewed papers into papers that use non-cooperative or cooperative games, simultaneous or sequential games, discrete or continuous games, and non-zero-sum or zero-sum games. Similarly, papers are also classified into two-player, three-player or multi-player game based papers. We also explore the nature of players and the construction of payoff functions in each scenario. Finally, we also identify gaps in literature where game theory could be fruitfully applied in scenarios hitherto unexplored using game theory. The presented analysis provides a concise summary of the state-of-the-art with regards to the use of game theory in defence applications and highlights the benefits and limitations of game theory in the considered scenarios.
Oxidative stress is a common mediator in pathogenicity of established cardiovascular risk factors. Furthermore, it likely mediates effects of emerging, less well-defined variables that contribute to ...residual risk not explained by traditional factors. Functional oxidative modifications of cellular proteins, both reversible and irreversible, are a causal step in cellular dysfunction. Identifying markers of oxidative stress has been the focus of many researchers as they have the potential to act as an "integrator" of a multitude of processes that drive cardiovascular pathobiology. One of the major challenges is the accurate quantification of reactive oxygen species with very short half-life. Redox-sensitive proteins with important cellular functions are confined to signalling microdomains in cardiovascular cells and are not readily available for quantification. A popular approach is the measurement of stable by-products modified under conditions of oxidative stress that have entered the circulation. However, these may not accurately reflect redox stress at the cell/tissue level. Many of these modifications are "functionally silent". Functional significance of the oxidative modifications enhances their validity as a proposed biological marker of cardiovascular disease, and is the strength of the redox cysteine modifications such as glutathionylation. We review selected biomarkers of oxidative stress that show promise in cardiovascular medicine, as well as new methodologies for high-throughput measurement in research and clinical settings. Although associated with disease severity, further studies are required to examine the utility of the most promising oxidative biomarkers to predict prognosis or response to treatment.
A large, prospective international registry was developed to evaluate the initial clinical applications of transcatheter tricuspid valve intervention (TTVI) with different devices.
TTVI for native ...tricuspid valve dysfunction has been emerging during the last few years as an alternative therapeutic option to serve a large high-risk population of patients with severe symptomatic tricuspid regurgitation (TR).
The TriValve Registry included 312 high-risk patients with severe TR (76.4 ± 8.5 years of age; 57% female; EuroSCORE II 9 ± 8%) at 18 centers. Interventions included repair at the level of the leaflets (MitraClip, Abbott Vascular, Santa Clara, California; PASCAL Edwards Lifesciences, Irvine, California), annulus (Cardioband, Edwards Lifesciences; TriCinch, 4tech, Galway, Ireland; Trialign, Mitraling, Tewksbury, Massachusetts), or coaptation (FORMA, Edwards Lifesciences) and replacement (Caval Implants, NaviGate, NaviGate Cardiac Structures, Lake Forest, California). Clinical outcomes were prospectively determined during mid-term follow-up.
A total of 108 patients (34.6%) had prior left heart valve intervention (84 surgical and 24 transcatheter, respectively). TR etiology was functional in 93%, and mean annular diameter was 46.9 ± 9 mm. In 75% of patients the regurgitant jet was central (vena contracta 1.1 ± 0.5; effective regurgitant orifice area 0.78 ± 0.6 cm
). Pre-procedural systolic pulmonary artery pressure was 41 ± 14.8 mm Hg. Implanted devices included: MitraClip in 210 cases, Trialign in 18 cases, TriCinch first generation in 14 cases, caval valve implantation in 30 cases, FORMA in 24 cases, Cardioband in 13 cases, NaviGate in 6 cases, and PASCAL in 1. In 64% of the cases, TTVI was performed as a stand-alone procedure. Procedural success (defined as the device successfully implanted and residual TR ≤2+) was 72.8%. Greater coaptation depth (odds ratio: 24.1; p = 0.002) was an independent predictor of reduced device success. Thirty-day mortality was 3.6% and was significantly lower among patients with procedural success (1.9% vs. 6.9%; p = 0.04); Actuarial survival at 1.5 years was 82.8 ± 4% and was significantly higher among patients who had procedural success achieved.
TTVI is feasible with different technologies, has a reasonable overall procedural success rate, and is associated with low mortality and significant clinical improvement. Mid-term survival is favorable in this high-risk population. Greater coaptation depth is associated with reduced procedural success, which is an independent predictor of mortality.
The clinical course of patients with moderate aortic stenosis (AS) remains incompletely defined.
This study sought to analyze the clinical course of moderate AS and compare it with other stages of ...the disease.
Multiple electronic databases were searched to identify studies on adult moderate AS. Random-effects models were used to derive pooled estimates. The primary endpoint was all-cause death. The secondary endpoints were cardiac death, heart failure, sudden death, and aortic valve replacement.
Among a total of 25 studies (12,143 moderate AS patients, 3.7 years of follow-up), pooled rates per 100 person-years were 9.0 (95% CI: 6.9 to 11.7) for all-cause death, 4.9 (95% CI: 3.1 to 7.5) for cardiac death, 3.9 (95% CI: 1.9 to 8.2) for heart failure, 1.1 (95% CI: 0.8 to 1.5) for sudden death, and 7.2 (95% CI: 4.3 to 12.2) for aortic valve replacement. Meta-regression analyses detected that diabetes (P = 0.019), coronary artery disease (P = 0.017), presence of symptoms (P < 0.001), and left ventricle (LV) dysfunction (P = 0.009) were associated with a significant impact on the overall estimate of all-cause death. All-cause mortality was higher in patients with reduced LV ejection fraction (<50%) than with normal LV ejection fraction: 16.5 (95% CI: 5.2 to 52.3) and 4.2 (95% CI: 1.4 to 12.8) per 100 person-years, respectively. Compared with moderate AS, the incidence rate difference of all-cause mortality was -3.9 (95% CI: -6.7 to -1.1) for no or mild AS and +2.2 (95% CI: +0.8 to +3.5) for severe AS patients.
Moderate AS appears to be associated with a mortality risk higher than no or mild AS but lower than severe AS, which increases in specific population subsets. The impact of early intervention in moderate AS patients having high-risk features deserves further investigation.
The molecular signatures of cells in the brain have been revealed in unprecedented detail, yet the ageing-associated genome-wide expression changes that may contribute to neurovascular dysfunction in ...neurodegenerative diseases remain elusive. Here, we report zonation-dependent transcriptomic changes in aged mouse brain endothelial cells (ECs), which prominently implicate altered immune/cytokine signaling in ECs of all vascular segments, and functional changes impacting the blood-brain barrier (BBB) and glucose/energy metabolism especially in capillary ECs (capECs). An overrepresentation of Alzheimer disease (AD) GWAS genes is evident among the human orthologs of the differentially expressed genes of aged capECs, while comparative analysis revealed a subset of concordantly downregulated, functionally important genes in human AD brains. Treatment with exenatide, a glucagon-like peptide-1 receptor agonist, strongly reverses aged mouse brain EC transcriptomic changes and BBB leakage, with associated attenuation of microglial priming. We thus revealed transcriptomic alterations underlying brain EC ageing that are complex yet pharmacologically reversible.
Purpose
Data on mental disorder prevalence and health service utilization required to inform healthcare management and planning are lacking in Hong Kong. The current study determined the prevalence ...of common mental disorders (CMD), and examined the patterns of mental health service utilization and associated factors.
Methods
We analyzed data from the Hong Kong Mental Morbidity Survey (HKMMS) of 5,719 Chinese adults aged 16–75 years in the general Hong Kong population, using the Chinese Revised Clinical Interview Schedule (CIS-R).
Results
The weighted prevalence estimate for any past-week CMD was 13.3 %, with mixed anxiety and depressive disorder being the most frequent diagnoses. CMD was positively associated with female gender, being divorced or separated, alcohol misuse, substance dependence, lack of regular physical exercise, and a family history of mental disorder. Among individuals with CMD, only 26 % had consulted mental health services in the past year; less than 10 % consulted general practitioners or family physicians. Lack of mental health service usage was significantly more likely in men and those with lower educational attainment.
Conclusions
Apart from attention to psychosocial risks, health and lifestyle factors are important considerations for mental health promotion. Service utilization for individuals with CMD in Hong Kong remains suboptimal, and would be enhanced by strengthening community primary care.
We aimed to identify the clinical characteristics and examine outcomes in patients with significant tricuspid regurgitation (TR) who received transcatheter tricuspid valve intervention (TTVI) ...compared with guideline directed medical therapy (GDMT).
Between 2015 and 2019, 124 patients with symptomatic severe TR were assessed at St. Michael's Hospital. Seventy-one patients were ineligible and received GDMT only while 53 patients received TTVI and GDMT. During follow-up, TTVI was associated with significant improvements in NYHA functional class and 6-min walk distance (p < .001). GDMT patients had lower survival (46.9% vs 75.1%, p = .047) and lower freedom from heart failure hospitalization (HHF) and mortality (33.2% vs 62.7%, p = .027), higher incidences per 100 person-year of gastrointestinal bleeding 15.58 (95% CI 8.90–25.31) vs 4.24 (95% CI 0.85–12.37), p = .04 and acute kidney injury 36.98 (95% CI 26.17–50.76) vs 14.12 (95% CI 6.76–25.96), p = .001 compared with TTVI patients.
TTVI in addition to GDMT was effective at improving TR symptoms, functional status, and was associated with lower rates of all-cause mortality, the combined endpoint of HHF and mortality, AKI and GI bleeding. Future randomized controlled trials on TTVI are needed.
•Severe tricuspid regurgitation (TR) is associated with significant morbidity and mortality.•Transcathether tricuspid valve intervention (TTVI) may reduce severity of TR.•TTVI may improve functional capacity and symptom burden.•TTVI may reduce hospitalization for heart failure and mortality.•TTVI may reduce incidence of renal injury and gastrointestinal bleed.
Aim
Young people in Hong Kong have been facing numerous population‐level events over the past year, including social unrest and the COVID‐19 pandemic. Representative data concerning the mental health ...of youths, however, is limited. The Hong Kong Youth Epidemiological Study of Mental Health (HK‐YES) is commissioned to provide the first representative prevalence estimates and correlates of mental disorders among young people in Hong Kong. It will also examine the help‐seeking behaviours, treatment rates, quality of life, and functional outcomes of the young people. More importantly, the direct and indirect economic costs of mental disorders in youths will be estimated.
Methods
A total of 4500 community‐dwelling participants aged 15–24 years from Hong Kong will be surveyed. Participants will be selected using a multistage stratified sampling design to provide representative estimates of the youth population in Hong Kong. All interviews will be conducted using computer‐assisted personal interviewing methods for assessments covering areas of psychiatric diagnoses, symptomatology, functioning, quality of life, disability, service utilization, health economic costs of mental disorders, and sociodemographic and lifestyle characteristics. A population‐weighted prevalence will be estimated using survey weights. Methods such as multivariate logistic and linear regression analyses will be used to calculate the risks and odds of factors that might be associated with different mental disorders.
Conclusion
As the first population‐based youth study in Hong Kong, HK‐YES collects extensive and representative data on different mental conditions and their associated factors among young people. The information gathered will be important for future planning on youth mental health services in Hong Kong and will offer the opportunity for a more meaningful comparison of data with other youth populations.
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