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Modern longitudinal studies collect feature data at many timepoints, often of the same order of sample size. Such studies are typically affected by dropout and positivity violations. We tackle these problems by generalizing effects of recent incremental interventions (which shift propensity scores rather than set treatment values deterministically) to accommodate multiple outcomes and subject dropout. We give an identifying expression for incremental intervention effects when dropout is conditionally ignorable (without requiring treatment positivity) and derive the nonparametric efficiency bound for estimating such effects. Then we present efficient nonparametric estimators, showing that they converge at fast parametric rates and yield uniform inferential guarantees, even when nuisance functions are estimated flexibly at slower rates. We also study the variance ratio of incremental intervention effects relative to more conventional deterministic effects in a novel infinite time horizon setting, where the number of timepoints can grow with sample size and show that incremental intervention effects yield near-exponential gains in statistical precision in this setup. Finally, we conclude with simulations and apply our methods in a study of the effect of low-dose aspirin on pregnancy outcomes.

Weighting is a general and often-used method for statistical adjustment. Weighting has two objectives: first, to balance covariate distributions, and second, to ensure that the weights have minimal dispersion and thus produce a more stable estimator. A recent, increasingly common approach directly optimizes the weights toward these two objectives. However, this approach has not yet been feasible in large-scale datasets when investigators wish to flexibly balance general basis functions in an extended feature space. To address this practical problem, we describe a scalable and flexible approach to weighting that integrates a basis expansion in a reproducing kernel Hilbert space with state-of-the-art convex optimization techniques. Specifically, we use the rank-restricted Nyström method to efficiently compute a kernel basis for balancing in nearly linear time and space, and then use the specialized first-order alternating direction method of multipliers to rapidly find the optimal weights. In an extensive simulation study, we provide new insights into the performance of weighting estimators in large datasets, showing that the proposed approach substantially outperforms others in terms of accuracy and speed. Finally, we use this weighting approach to conduct a national study of the relationship between hospital profit status and heart attack outcomes in a comprehensive dataset of 1.27 million patients. We find that for-profit hospitals use interventional cardiology to treat heart attacks at similar rates as other hospitals but have higher mortality and readmission rates. [ABSTRACT FROM AUTHOR]

Computer Adaptive Testing (CAT) has been highlighted as a promising assessment method to fulfill two testing purposes: estimating student academic ability and classifying student academic level. In this paper, assessment for we introduced the Web-based Adaptive Testing System (WATS) developed to support a cost effective assessment for classifying students' ability into different academic levels. Instead of using a traditional paper and pencil test, the WATS is expected to serve as an alternate method to promptly diagnosis and identify underachieving students through Web-based testing. The WATS can also help provide students with appropriate learning contents and necessary academic support in time. In this paper, theoretical background and structure of WATS, item construction process based upon item response theory, and user interfaces of WATS were discussed. (Contains 10 figures.)

Electroless composite plating enables uniform and thin surface treatment along with composite deposition using nanoparticles. Among such particles, polytetrafluoroethylene (PTFE) is capable of dry lubrication because of its self-lubricating properties. Specifically, the PTFE content in a plating layer increases with the concentration of PTFE in the plating bath. However, a high concentration of PTFE interferes with the co-deposition of Ni and P, thereby reducing the plating speed. Additionally, PTFE is unevenly deposited on the surface of the plating layer. Consequently, a method for increasing the PTFE content at low PTFE concentrations is required. Therefore, in this study, a stirring process in a low-PTFE-concentration plating bath and a process wherein PTFE precipitates on a specimen without stirring were combined. The PTFE content of the plated layer deposited on high carbon steel, plated layer deposition rate, average friction co-efficient, static contact angle, and surface energy were evaluated as 25.96%, 3.44 µm/40 min, 0.195, 141.9°, and 2.74 mN/m, respectively. This technique prevented the decrease in the deposition rate of the plating layer and led to high PTFE content in the plating layer. Notably, even a thin plating layer (5 μm or less in thickness) showed excellent surface characteristics. [ABSTRACT FROM AUTHOR]

An architect applies glazing to a building envelope to express an expansiveness and hi-tech quality through transparency. However, in small over-glazed buildings, the glazed envelopes often lead to an inadequate comfort level in summer, when much cooling energy is needed to improve the comfort level and occupants are forced to avoid the use of glazed envelopes. This paper presents the results of comfort survey and measurements on the indoor environment of an architecturally significant small glazed-envelope building that has received many awards for its architectural design quality, and analyzes design approaches to improve the comfort level of its occupants. During the late summer of 2002, the comfort survey was conducted, polling responses from 57 office workers, while simultaneously measuring air/surface temperatures and daylight factors. Numerical simulations were performed to investigate 13 design approaches for the improvement of the comfort level. From the temperature/daylight factor measurements, the indoor air temperature did not maintain the set-point temperature of 24.0 [degrees]C even with the operation of the air-conditioning system. When using the roller shades, the intensities of illumination and luminance on each measured desk surface were unevenly distributed from 650 Lux and 51 cd/[m.sup.2] to 6291 Lux and 310 cd/[m.sup.2]. From the survey, office workers suffered thermal discomfort and uncomfortable glare from high or non-uniform brightness distributions in the working areas. From the numerical analyses using computer simulations, the double-skin envelopes with the sufficient intermediate space and shading devices were suggested to improve the comfort level. Keywords: Comfort level; Glazed envelope; Small-sized building; Comfort survey; Measurement; Over-glazed building

The Receptor for Advanced Glycation End products (RAGE) is a pattern recognition receptor that signals for inflammation via the NF‐κB pathway. RAGE has been pursued as a potential target to suppress symptoms of diabetes and is of interest in a number of other diseases associated with chronic inflammation, such as inflammatory bowel disease and bronchopulmonary dysplasia. Screening and optimization have previously produced small molecules that inhibit the activity of RAGE in cell‐based assays, but efforts to develop a therapeutically viable direct‐binding RAGE inhibitor have yet to be successful. Here, we show that a fragment‐based approach can be applied to discover fundamentally new types of RAGE inhibitors that specifically target the ligand‐binding surface. A series of systematic assays of structural stability, solubility, and crystallization were performed to select constructs of the RAGE ligand‐binding domain and optimize conditions for NMR‐based screening and co‐crystallization of RAGE with hit fragments. An NMR‐based screen of a highly curated ~14 000‐member fragment library produced 21 fragment leads. Of these, three were selected for elaboration based on structure‐activity relationships generated through cycles of structural analysis by X‐ray crystallography, structure‐guided design principles, and synthetic chemistry. These results, combined with crystal structures of the first linked fragment compounds, demonstrate the applicability of the fragment‐based approach to the discovery of RAGE inhibitors. [ABSTRACT FROM AUTHOR]