Intrinsic expansions for averaged diffusion processes

We show that the rate of convergence of asymptotic expansions for solutions of SDEs is generally higher in the case of degenerate (or partial) diffusion compared to the elliptic case, i.e. it is higher when the Brownian motion directly acts only on some components of the diffusion. In the scalar case, this phenomenon was already observed in (Gobet and Miri 2014) using Malliavin calculus techniques. In this paper, we provide a general and detailed analysis by employing the recent study of intrinsic functional spaces related to hypoelliptic Kolmogorov operators in (Pagliarani et al. 2016). Relevant applications to finance are discussed, in particular in the study of path-dependent derivatives (e.g. Asian options) and in models incorporating dependence on past information

A Semantic Grid Service for Experimentation with an Agent-Based Model of Land-Use Change

Agent-based models, perhaps more than other models, feature large numbers of parameters and potentially generate vast quantities of results data. This paper shows through the FEARLUS-G project (an ESRC e-Social Science Initiative Pilot Demonstrator Project) how deploying an agent-based model on the Semantic Grid facilitates international collaboration on investigations using such a model, and contributes to establishing rigorous working practices with agent-based models as part of good science in social simulation. The experimental workflow is described explicitly using an ontology, and a Semantic Grid service with a web interface implements the workflow. Users are able to compare their parameter settings and results, and relate their work with the model to wider scientific debate.Agent-Based Social Simulation, Experiments, Ontologies, Replication, Semantic Grid

Impact of COVID-19 on health risk behaviors in northern California: A cross-sectional survey

The COVID-19 pandemic has been disruptive, unevenly impacting health behaviors in different geographical regions and population groups. We examined how COVID-19 affected perceived changes in physical activity, sleep, and diet and the impact of socio-demographic variables on a calculated health risk behavior score. In this cross-sectional study, 505 residents of northern California completed a web-based survey from August to November of 2020. Chi-square and multivariable linear regression analyses examined the association between socio-demographic variables and the health risk behavior score. Approximately 84 % of respondents experienced at least one unfavorable behavior change after the pandemic, with 49.5 % indicating a reduction in physical activity, 29.7 % a decrease in sleep, 33.1 % an increase in sugary snack consumption, and 29.3 % a decrease in fruit and vegetable intake. Multivariate analyses indicated a higher health risk behavior score (less favorable) for females compared to males (male beta = -0.815, p \u3c 0.0001) and Hispanics compared to Whites (Hispanics beta = 0.396, p = 0.033). The negative changes in health behavior observed in females could be attributed to a higher reduction in fruit and vegetable consumption, and a larger increase in sugary and salty snacks when compared to males. A higher reduction in exercise, sleep, and fruit and vegetable intake were the main drivers of the unfavorable results seen for Hispanics when compared to Whites. Findings highlight the detrimental behavioral changes during the COVID-19 pandemic and the disproportionate impact on Hispanics and women. These results are valuable to policymakers to identify ways to support those most affected by the pandemic and its potential long-term effects

e-Social Science and Evidence-Based Policy Assessment : Challenges and Solutions

Peer reviewedPreprin

How old are you? Newborn gestational age discriminates neonatal resuscitation practices in the Italian debate

<p>Abstract</p> <p>Background</p> <p>Multidisciplinary study groups have produced documents in an attempt to support decisions regarding whether to resuscitate "at risk" newborns or not. Moreover, there has been an increasingly insistent request for juridical regulation of neonatal resuscitation practices as well as for clarification of the role of parents in decisions regarding this kind of assistance. The crux of the matter is whether strict guidelines, reference standards based on the parameter of gestational age and authority rules are necessary.</p> <p>Discussion</p> <p>The Italian scenario reflects the current animated debate, illustrating the difficulty intrinsic in rigid guidelines on the subject, especially when gestational age is taken as a reference parameter for the medical decision.</p> <p>Summary</p> <p>Concerning the decision to interrupt or not to initiate resuscitation procedures on low gestational age newborns, physicians do not need rigid rules based on inflexible gestational age and birth weight guidelines. Guidance in addressing the difficult and trying issues associated with infants born at the margins of viability with a realistic assessment of the infant's clinical condition must be based on the infant's best interests, with clinicians and parents entering into what has been described as a "partnership of care".</p

Exponential stability of the wave equation with memory and time delay

We study the asymptotic behaviour of the wave equation with viscoelastic damping in presence of a time-delayed damping. We prove exponential stability if the amplitude of the time delay term is small enough

Development of a digital tool to overcome the challenges of rural food SMEs

It has been recognised that throughout the UK, rural economies have a significant potential for growth but despite the potential for growth, many rural businesses face barriers that prohibit their expansion. In this study, we focus on one particular group of rural small- to medium-sized enterprises (SMEs): food and drink producers. Through user engagement activities, we identify the issues and needs associated with distributing products to the market, in order to understand the main issues which prevent rural food and drink SMEs from expansion, and to establish the requirements for a digital solution to this challenge

tert-Butyl 2-(4-chloro­benzo­yl)-2-methyl­propanoate

The title compound, C15H19ClO3, is bent with a dihedral angle of 72.02 (9)° between the mean planes of the benzene ring and a group encompassing the ester functionality (O=C—O—C). In the crystal, mol­ecules related by inversion symmetry are connected by weak C—H⋯O inter­actions into infinite chains. These inter­actions involve H atoms from a methyl group of the dimethyl residue and the O atoms of the ketone on one side of a mol­ecule; on the other side there are inter­actions between H atoms of the benzene ring and the carbonyl O atoms of the ester functionality. There are no directional inter­actions between the chains

A novel comprehensive clinical stratification model to refine prognosis of glioblastoma patients undergoing surgical resection

Despite recent discoveries in genetics and molecular fields, glioblastoma (GBM) prognosis still remains unfavorable with less than 10% of patients alive 5 years after diagnosis. Numerous studies have focused on the research of biological biomarkers to stratify GBM patients. We addressed this issue in our study by using clinical/molecular and image data, which is generally available to Neurosurgical Departments in order to create a prognostic score that can be useful to stratify GBM patients undergoing surgical resection. By using the random forest approach [CART analysis (classification and regression tree)] on Survival time data of 465 cases, we developed a new prediction score resulting in 10 groups based on extent of resection (EOR), age, tumor volumetric features, intraoperative protocols and tumor molecular classes. The resulting tree was trimmed according to similarities in the relative hazard ratios amongst groups, giving rise to a 5-group classification tree. These 5 groups were different in terms of overall survival (OS) (p < 0.000). The score performance in predicting death was defined by a Harrell\u2019s c-index of 0.79 (95% confidence interval [0.76\u20130.81]). The proposed score could be useful in a clinical setting to refine the prognosis of GBM patients after surgery and prior to postoperative treatment