Paired and altruistic kidney donation in the UK: algorithms and experimentation

We study the computational problem of identifying optimal sets of kidney exchanges in the UK. We show how to expand an integer programming-based formulation [1, 19] in order to model the criteria that constitute the UK definition of optimality. The software arising from this work has been used by the National Health Service Blood and Transplant to find optimal sets of kidney exchanges for their National Living Donor Kidney Sharing Schemes since July 2008.We report on the characteristics of the solutions that have been obtained in matching runs of the scheme since this time. We then present empirical results arising from the real datasets that stem from these matching runs, with the aim of establishing the extent to which the particular optimality criteria that are present in the UK influence the structure of the solutions that are ultimately computed. A key observation is that allowing 4-way exchanges would be likely to lead to a significant number of additional transplants

Fathers of special needs infants and toddlers enrolled in early intervention programs : patterns of involvement.

EducationDoctor of Education (Ed.D.

Human placental cytotrophoblasts produce the immunosuppressive cytokine interleukin 10.

The mechanism by which the mammalian mother accepts the implanting fetus as an allograft remains unexplained, but is likely to be the result of a combination of factors. Mononuclear cytotrophoblasts, the specialized fetal cells of the placenta that invade the uterus, play an important role. These cells express HLA-G, an unusual major histocompatibility complex class I-B molecule, and secrete cytokines and pregnancy-specific proteins that can regulate immune function. We investigated whether cytotrophoblasts secrete interleukin 10 (IL-10), a cytokine that potently inhibits alloresponses in mixed lymphocyte reactions. Cytotrophoblasts from all stages of pregnancy produced IL-10 in vitro, but neither placental fibroblasts nor choriocarcinoma (malignant trophoblast) cell lines did so. Spontaneous IL-10 production averaged 650, 853, and 992 pg/10(6) cells in the first, second, and third trimesters of pregnancy, respectively. IL-10 secretion dropped approximately 10-fold after the first 24 h of culture, and was paralleled by a decrease in messenger RNA. IL-10 messenger RNA was detected in biopsies of the placenta and the portion of the uterus that contains invasive cytotrophoblasts, suggesting that this cytokine is also produced in vivo. IL-10 secreted by cytotrophoblasts in vitro is bioactive, as determined by its ability to suppress interferon gamma production in an allogeneic mixed lymphocyte reaction. We conclude that human cytotrophoblast IL-10 may be an important factor that contributes to maternal tolerance of the allogeneic fetus

A likelihood method to cross-calibrate air-shower detectors

We present a detailed statistical treatment of the energy calibration of hybrid air-shower detectors, which combine a surface detector array and a fluorescence detector, to obtain an unbiased estimate of the calibration curve. The special features of calibration data from air showers prevent unbiased results, if a standard least-squares fit is applied to the problem. We develop a general maximum-likelihood approach, based on the detailed statistical model, to solve the problem. Our approach was developed for the Pierre Auger Observatory, but the applied principles are general and can be transferred to other air-shower experiments, even to the cross-calibration of other observables. Since our general likelihood function is expensive to compute, we derive two approximations with significantly smaller computational cost. In the recent years both have been used to calibrate data of the Pierre Auger Observatory. We demonstrate that these approximations introduce negligible bias when they are applied to simulated toy experiments, which mimic realistic experimental conditions.Comment: 10 pages, 7 figure