Nonlinear association structures in flexible Bayesian additive joint models

Joint models of longitudinal and survival data have become an important tool for modeling associations between longitudinal biomarkers and event processes. The association between marker and log-hazard is assumed to be linear in existing shared random effects models, with this assumption usually remaining unchecked. We present an extended framework of flexible additive joint models that allows the estimation of nonlinear, covariate specific associations by making use of Bayesian P-splines. Our joint models are estimated in a Bayesian framework using structured additive predictors for all model components, allowing for great flexibility in the specification of smooth nonlinear, time-varying and random effects terms for longitudinal submodel, survival submodel and their association. The ability to capture truly linear and nonlinear associations is assessed in simulations and illustrated on the widely studied biomedical data on the rare fatal liver disease primary biliary cirrhosis. All methods are implemented in the R package bamlss to facilitate the application of this flexible joint model in practice.Comment: Changes to initial commit: minor language editing, additional information in Section 4, formatting in Supplementary Informatio

Cruise report RV "Alkor" Cruise No. AL451

This report is based on preliminary data. Ventspils (Latvia). 01-02 March 2015 and 07-09 March 2015 Purpose of the cruise The original scientific goal of this cruise, conducted in the framework of the WGL/Pakt project ILWAO-II, was the investigation of the role of internal waves for basin-scale vertical mixing in the deep basins of the Baltic Sea. In agreement with IOW’s board, however, it was decided to devote a substantial part of the cruise time to the observation of one of the rare major saline inflow events that reached the central Baltic Sea exactly at the time of this cruise. In addition to the physical measurements, microbiological and chemical investigations were conducted, focusing on the role of methane-oxidizing bacteria in pelagic redoxclines

Cruise Report R/V Alkor Cruise- No. AL400

04.-20. September 2012; Dates and names of ports of call Visby (Sweden) from 13 to 15 September 2012; This interdisciplinary cruise aimed at exploring the effects of lateral intrusions and turbulent mixing on the microbiology and biogeochemistry of the redoxcline in the deep basins of the Baltic Sea

Intercountry Adoption and Child Sponsorship in Vietnam: A Practicum-Based Exploration of a Complex Relationship

For over a decade, Vietnam ranked in the top ten countries providing the most children for intercountry adoption (ICA), sending almost 11,000 children abroad since 2003 (U.S. State Department, 2015). It is likely that many of these children, however, were not orphans; evidence reveals that a lucrative baby-buying industry falsified information and trafficked children for years in order to meet the high international demand for healthy infants. In this paper, I relate this history of ICA fraud to contemporary child sponsorship in Vietnam. I find that ICA and child sponsorship are intertwined in two contradictory ways. First, child sponsorship programs justly work to reduce the systematic need for ICA; through a combination of community development programs and individualized support, these programs combat the root causes that lead to child abandonment. At the same time, however, child sponsorship also mirrors ICA’s most fundamental problems, such as the prioritization of foreign needs over effective outcomes. Child sponsorship is thus simultaneously working to reduce the past problems of ICA while also inadvertently carrying on its most problematic legacies. I investigated models and applications of child sponsorship in Vietnam through a practicum at the Center for Community Health and Development (COHED) in Hanoi, Vietnam. I worked with COHED for a total of 90 hours in three weeks. My practicum focus project was to create a child sponsorship program implementation strategy; upon completion, I presented my research and preliminary recommendations to COHED’s directors. For my research, I also interviewed the country director of Holt International

Triangular Gk-splines

In this paper a new approach is presented to construct piecewise polynomial G^k-surfaces of arbitrary topology and smoothness order k>= 1 of degree O(k). This approach generalizes some results presented in 1997 in CAGD and in 1999 at the St. Malo conference, respectively. In our construction only 4n polynomial patches are needed to fill an n-sided hole in a generalized C^k-(half)-boxspline surface. This is achieved by coalescing certain control points while at the same time maintaining a regular parametrization

A generic length-scale equation for geophysical turbulence models

A generalization of a class of differential length-scale equations typically used in second-order turbulence models for oceanic flows is suggested. Commonly used models, like the k-ε model and the Mellor-Yamada model, can be recovered as special cases of this generic model, and thus can be rationally compared. In addition, a method is proposed that yields a generalized framework for the calibration of the most frequently used class of differential length-scale equations. The generic model, calibrated with this method, exhibits a greater range of applicability than any of the traditional models. Stratified flows, plane mixing layers, and turbulence introduced by breaking surface waves are considered besides some classical test cases

Survey on Benchmarks for a GPU Based Multi Camera Stereo Matching Algorithm

Stereo matching algorithms and multi camera reconstruction algorithms are usually compared using benchmarks. These benchmarks compare the quality of the resulting depth map or reconstructed surface mesh. We describe the differences between several known stereo and multi-view stereo benchmarks and their various datasets. Also the modifications that are necessary to use our own GPU based multi camera stereo matching algorithm with the data from these benchmarks are discussed

Reply to: “Comments on ‘A generic length-scale equation for geophysical turbulence models’ ”by L. Kantha and S. Carniel

Recently, Kantha and Carniel (2003) commented on some earlier work of Kantha (2003) and Umlauf and Burchard (2003) on the formulation of a generalized length-scale equation in Reynolds stress models for geophysical flows. With the present short note, we respond to their major criticism of the Umlauf and Burchard (2003) generic two-equation model..