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Recent results in the literature highlight the impact of nonlinear inertial forces on the post-flutter limit cycle oscillation (LCO) characteristics of highly deflected structures in supersonic axial flow. The current investigation examines how the ability to passively modulate nonlinear inertial forces may alter the overall aeroelastic response. The structural model is a one-dimensional nonlinear inextensible plate subject to nonlinear aerodynamic forces in accordance with a new, geometrically modified third-order Piston Theory. For the linear aeroelastic case, we find that nonhomogeneous mass distribution elicits discontinuous increases in the critical Mach number for flutter and several flutter mode-switching phenomena that are not observed when mass is added homogeneously. The existence of several different flutter mode mechanisms as a function of a concentrated mass location leads to different post-flutter LCO amplitude behavior. This is found to transition the underlying nonlinear structural dynamics to either be stiffening (when lower-order modes merge) or softening (when higher-order modes merge), which in turn alter the influence of nonlinear aerodynamic forces. We also address discrepancies in LCO amplitude trends due to the nonlinear inertial forces previously reported in the literature.

Enterprises are increasingly considering security as an added cost, making it necessary for those enterprises to see a tangible incentive in adopting security measures. Despite data breach laws, prior studies have suggested that only 4% of reported data breach incidents have resulted in litigation in federal courts, showing the limited legal ramifications of security breaches and vulnerabilities. In this paper, we study the hidden cost of software vulnerabilities reported in the National Vulnerability Database (NVD) through stock price analysis. We perform a high-fidelity data augmentation to ensure data reliability and to estimate vulnerability disclosure dates as a baseline for estimating the implication of software vulnerabilities. We further build a model for stock price prediction using the nonlinear autoregressive neural network with exogenous factors (NARX) Neural Network model to estimate the effect of vulnerability disclosure on the stock price. Compared to prior work, which relies on linear regression models, our approach is shown to provide better prediction performance. Our analysis also shows that the effect of vulnerabilities on vendors varies, and greatly depends on the specific software industry. Whereas some industries are shown statistically to be affected negatively by the release of software vulnerabilities, even when those vulnerabilities are not broadly covered by the media, some others were not affected at all.

Background Data breaches are an inevitable risk to hospitals operating with information technology. The financial costs associated with data breaches are also growing. The costs associated with a data breach may divert resources away from patient care, thus negatively affecting hospital productivity. Objective After a data breach, the resulting regulatory enforcement and remediation are a shock to a hospital’s patient care delivery. Exploiting this shock, this study aimed to investigate the association between hospital data breaches and productivity by using a generalized difference-in-differences model with multiple prebreach and postbreach periods. Methods The study analyzed the hospital financial data of the California Office of Statewide Health Planning and Development from 2012 to 2016. The study sample was an unbalanced panel of hospitals with 2610 unique hospital-year observations, including general acute care hospitals. California hospital data were merged with breach data published by the US Department of Health and Human Services. The dependent variable was hospital productivity measured as value added. The difference-in-differences model was estimated using fixed effects regression. Results Hospital productivity did not significantly differ from the baseline for 3 years after a breach. Data breaches were not significantly associated with a reduction in hospital productivity. Before a breach, the productivity of hospitals that experienced a data breach maintained a parallel trend with control hospitals. Conclusions Hospital productivity was resilient against the shocks from a data breach. Nonetheless, data breaches continue to threaten hospitals; therefore, health care workers should be trained in cybersecurity to mitigate disruptions.

Introduction In juvenile idiopathic arthritis (JIA), interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) are associated with development and progression of JIA. We investigated whether IL-1, IL-6, and TNF-α polymorphisms were associated with susceptibility to JIA. Evidence acquisition A meta-analysis was conducted on the associations between IL-1α- 899 C/T, IL-1β-511 C/T, IL-6-174 G/C, and TNF-α-308 G/A and -238 G/A polymorphisms, and JIA (PubMed and Embase). Evidence synthesis A total of 27 studies involving 4,678 JIA patients and 7,634 controls were considered in the meta-analysis. There was no association between the IL-1α-899 C/T, IL-1β- 511 C/T, IL-6-174 G/C, and TNF-α-308 G/A and -238 G/A polymorphisms, and JIA in allele contrast or any other genetic models. In subgroup analysis based on subtype, except for the dominant model of TNF-α-238 G/A, systemic JIA was not significantly associated with IL-6 and TNF-α polymorphisms. In Caucasians, the dominant and additive models of IL-1β-511 C/T were significantly associated with JIA (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.09-2.00, P =0.01; OR 1.46, 95% CI 1.05-2.03, P =0.02, respectively). Conclusions This meta-analysis showed no association between IL-1, IL-6, and TNF-α polymorphisms, and JIA, but the TT genotype of IL-1β -511 C/T was associated with higher prevalence of JIA in Caucasians.

To estimate the relationship between data breaches and hospital advertising expenditures.Observational data on hospital expenditures were analyzed using a propensity score-matched regression. The regression was specified as a generalized linear model using a gamma distribution and log link.The study sample included Medicare hospitals captured by a survey of traditional media outlets. Hospitals included were nonfederal acute care inpatient hospitals from 2011 to 2014. Voicetrak provided data on hospital advertising expenditures. The Healthcare Cost Report Information System provided data on hospital characteristics and financial variables. Study groups were matched using observable characteristics, such as revenue, number of beds, discharges, ownership, and teaching status. The study excluded hospitals in Maryland and the US territories for financial reporting consistency. Data breaches included theft, loss, unauthorized access/disclosure, improper disposal, and hacking. Advertising expenditures were collected from media outlets including television, radio, newspapers and business journals, and local magazines in a city/metropolitan area.Breached hospitals (n = 72) were more likely to be large, teaching, and urban hospitals relative to the control group (unweighted n = 915). A data breach was associated with a 64% (95% CI, 7.2%-252%; P = .023) increase in annual advertising expenditures, holding observable characteristics constant.Breached hospitals were associated with significantly higher advertising expenditures in the 2 years after the breach. Efforts to repair the hospital's image and minimize patient loss to competitors are potential drivers of the increased spending. Advertising costs subsequent to a breach are another cost to the healthcare system that could be avoided with better data security.

Hospital capital investment is important for acquiring and maintaining technology and equipment needed to provide health care. Reduction in capital investment by a hospital has negative implications for patient outcomes. Most hospitals rely on debt and internal cash flow to fund capital investment. The great recession may have made it difficult for hospitals to borrow, thus reducing their capital investment. I investigated the impact of the great recession on capital investment made by California hospitals. Modeling how hospital capital investment may have been liquidity constrained during the recession is a novel contribution to the literature. I estimated the model with California Office of Statewide Health Planning and Development data and system generalized method of moments. Findings suggest that not-for-profit and public hospitals were liquidity constrained during the recession. Comparing the changes in hospital capital investment between 2006 and 2009 showed that hospitals used cash flow to increase capital investment by $2.45 million, other things equal.

ObjectivePain and depression are prevalent and treatable symptoms among patients with cancer, yet they are often undetected and undertreated. The Indiana Cancer Pain and Depression (INCPAD) trial demonstrated that telecare management can improve pain and depression outcomes. This article investigates the incremental cost effectiveness of the INCPAD intervention.MethodsThe INCPAD trial was conducted in 16 community-based urban and rural oncology practices in Indiana. Of the 405 participants, 202 were randomized to the intervention group and 203 to the usual-care group. Intervention costs were determined, and effectiveness outcomes were depression-free days and quality-adjusted life years.ResultsThe intervention group was associated with a yearly increase of 60.3 depression-free days (S.E.=15.4; P

The 2007-09 recession led to an overall slowing in health care spending growth, but it is unclear whether the slowed spending growth had different impacts on adults and children. Although most children are healthy, forgoing routine health care could have long-term adverse implications for public health. Furthermore, children with special health care needs are at risk of adverse outcomes if they do not receive adequate care. Focusing on privately insured families with children, we investigated how out-of-pocket spending trends changed before and during the recession. Medical Expenditure Panel Survey data from the period 2001-09 revealed that the recession did not affect out-of-pocket spending for most children, but it led to a decline in spending for children with special needs, who had much higher out-of-pocket spending at baseline. Adults had significantly lower out-of-pocket spending during the recession, which suggests that parents may reduce their own medical care in difficult economic times to meet their children's health care needs.

“Catalyst-free” trimethylsilyl end-blocked polydimethylsiloxanes of Mn = 68,300 and 111,000 were isothermally depolymerized above 400°C. The volatilized products were a mixture of cyclic oligomers and trace quantities of Me3Si(OSiMe2)nOSiMe3 (n = 0,1). The relative degree of polymerization was followed as a function of fractional conversion. The data were consistent with the oretical curves for a mechanism involving initiation by random siloxane bond cleavage followed by a rapid and complete unzipping of the kinetically active fragments. It is suggested that catalysis may be responsible for the initiation process, thus accounting for the low activation energy (43 Kcal/mol) relative to the siloxane bond energy (108 kcal/mol).