Evolution of the Dependence of Residual Lifetimes

We investigate the dependence properties of a vector of residual lifetimes by means of the copula associated with the conditional distribution function. In particular, the evolution of positive dependence properties (like quadrant dependence and total positivity) are analyzed and expressions for the evolution of measures of association are given

Water-waves modes trapped in a canal by a body with the rough surface

The problem about a body in a three dimensional infinite channel is considered in the framework of the theory of linear water-waves. The body has a rough surface characterized by a small parameter $\epsilon>0$ while the distance of the body to the water surface is also of order $\epsilon$. Under a certain symmetry assumption, the accumulation effect for trapped mode frequencies is established, namely, it is proved that, for any given $d>0$ and integer $N>0$, there exists $\epsilon(d,N)>0$ such that the problem has at least $N$ eigenvalues in the interval $(0,d)$ of the continuous spectrum in the case $\epsilon\in(0,\epsilon(d,N))$. The corresponding eigenfunctions decay exponentially at infinity, have finite energy, and imply trapped modes.Comment: 25 pages, 8 figure

The localization effect for eigenfunctions of the mixed boundary value problem in a thin cylinder with distorted ends

A simple sufficient condition on curved end of a straight cylinder is found that provides a localization of the principal eigenfunction of the mixed boundary value for the Laplace operator with the Dirichlet conditions on the lateral side. Namely, the eigenfunction concentrates in the vicinity of the ends and decays exponentially in the interior. Similar effects are observed in the Dirichlet and Neumann problems, too.Comment: 25 pages, 10 figure

A model for the analysis of security policies in service function chains

Two emerging architectural paradigms, i.e., Software Defined Networking (SDN) and Network Function Virtualization (NFV), enable the deployment and management of Service Function Chains (SFCs). A SFC is an ordered sequence of abstract Service Functions (SFs), e.g., firewalls, VPN-gateways,traffic monitors, that packets have to traverse in the route from source to destination. While this appealing solution offers significant advantages in terms of flexibility, it also introduces new challenges such as the correct configuration and ordering of SFs in the chain to satisfy overall security requirements. This paper presents a formal model conceived to enable the verification of correct policy enforcements in SFCs. Software tools based on the model can then be designed to cope with unwanted network behaviors (e.g., security flaws) deriving from incorrect interactions of SFs in the same SFC

Courts in more republican-leaning counties sentence black individuals to longer prison terms than white individuals

The United States puts more people in prison than any other country in the world, and Black and Latinx individuals are disproportionately incarcerated and for longer. In new research which examines over 500,000 people admitted to state prisons through county courts, Katherine A. Durante finds that Black and Latinx individuals are sentenced, on average, for longer than White individuals, and that Black individuals are sentenced more harshly as the percentage of voters for Donald Trump in a county increases. These findings, she writes, raise questions of bias and unequal justice in the US justice system

Decision tree for identifying pertinent integration procedures and joint displays in mixed methods research

Aims: To propose a decision tree for identifying appropriate integration procedures and joint displays for achieving integration in mixed methods studies. Design: A methodological discussion. Data Sources: Methodological literature including mixed methods textbooks, methodological reviews and studies published in the last 10 years (2012–2022). Implications for Nursing: Mixed methods are instrumental to study complex nursing care processes and health-human phenomena. Nurse researchers can use this decision tree to choose the most appropriate integration procedures to overcome the integration challenge when designing and conducting mixed methods nursing studies. Conclusion: Integration procedures and joint displays are the most widely used methods for tackling the integration challenge in mixed methods research (MMR). The multifaceted and contingent nature of these methods are beneficial for their tailored and adapted use at the data collection, analysis, interpretation and reporting levels. The use of the most pertinent integration procedures and joint displays is critical for ensuring quality in MMR. Impact: A growing methodological literature on MMR offers a wide range of integration procedures and techniques. Therefore, choosing appropriate integration procedures and analysis methods can be challenging for nurse researchers interested in conducting mixed methods studies. A decision tree is developed outlining 14 integration procedures and their corresponding mixed methods designs, purposes and joint displays. Examples of mixed methods studies in the discipline of nursing are presented to illustrate the implementation of the integration procedures. The decision tree can serve as a straightforward methodological tool for decision making in MMR. Nurse researchers can effectively use this decision tree for research and teaching purposes. Patient or Public Contribution: No direct patient or public contribution

Chromosome Aberrations in Astronauts

A review of currently available data on in vivo induced chromosome damage in the blood lymphocytes of astronauts proves that, after protracted exposure of a few months or more to space radiation, cytogenetic biodosimetry analyses of blood collected within a week or two of return from space provides a reliable estimate of equivalent radiation dose and risk. Recent studies indicate that biodosimetry estimates from single spaceflights lie within the range expected from physical dosimetry and biophysical models, but very large uncertainties are associated with single individual measurements and the total sample population remains low. Retrospective doses may be more difficult to estimate because of the fairly rapid time-dependent loss of "stable" aberrations in blood lymphocytes. Also, biodosimetry estimates from individuals who participate in multiple missions, or very long (interplanetary) missions, may be complicated by an adaptive response to space radiation and/or changes in lymphocyte survival and repopulation. A discussion of published data is presented and specific issues related to space radiation biodosimetry protocols are discussed