Underwater sensor networks (UWSNs) have become a hot research topic because of their various aquatic applications. As the underwater sensor nodes are powered by built-in batteries which are difficult to replace, extending the network lifetime is a most urgent need. Due to the low and variable transmission speed of sound, the design of reliable routing algorithms for UWSNs is challenging. In thi...

BACKGROUND Awareness of chronic kidney disease (CKD), defined by kidney damage or reduced glomerular filtration rate, remains low in the United States, and few estimates of its future burden exist. STUDY DESIGN We used the CKD Health Policy Model to simulate the residual lifetime incidence of CKD and project the prevalence of CKD in 2020 and 2030. The simulation sample was based on nationally...

BACKGROUND Ecstasy is a widely used psychoactive drug that users often take because they experience positive effects such as increased euphoria, sociability, elevated mood, and heightened sensations. Ecstasy use is not harmless and several immediate and long term side effects have been identified. Lifetime ecstasy use is likely to be partly influenced by genetic factors, but no twin study has d...

Life is inherently risky. Some individuals manage to avoid the consequences of these risks over many years, whereas others are not so fortunate. The lifetime risk of dying, of course, is 100%. However, the magnitude of the risk for acquiring a diagnosis of a specific disease or groupofdiseases overa lifetime (also called cumulative incidence of diseases) varies widely according to the frequency...

Using a mean field approximation we calculate the lifetime of thermotlynamically unstable bilayers of a specific initial conformation in the Witlom mortel of microemulsions. For itlentical initial conformations of these mode[ bilayers, we study the tlepentlence of the lifetime on the initial magnetization of the central layer, the temperature. antl the elastic curvature of the amphiphilic membr...

Wireless sensor networks (WSNs) are composed of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it. Energy efficiency and network lifetime are two challenges that most of researchers deal with. In general, base station (BS) used to retrieve data from sensor nodes is far from the sensor field and how to adjust the communication between nodes...

This paper is about how to use data from a random sample of customer relationships to calculate an appropriate average Customer Lifetime Value (CLV). When the sample contains only completed relationships, the simple unweighted average is appropriate. When the sample contains a mix of active and completed relationships, the lifetimes of the active relationships are said to be right censored beca...

As a generalization of the accelerated failure time models, we consider parametric models of lifetime Y, where the conditional mean E(Y|X;beta) can depend nonlinearly on the covariates X and some parameters beta. The error distribution can be heteroscedastic and dependent on X. With observed data subject to right censoring, we propose regression analysis for beta based on Kaplan- Meier estimate...