Curbing Cream-Skimming: Evidence on Enrolment Incentives

Can enrolment incentives reduce the incidence of cream-skimming in the delivery of public sector services (e.g. education, health, job training)? In the context of a large government job training program, we investigate whether the use of enrolment incentives that set different 'shadow prices' for serving different demographic subgroups of clients, influence case workers' choice of intake population. Exploiting exogenous variation in these shadow prices, we show that training agencies change the composition of their enrollee populations in response to changes in the incentives, increasing the relative fraction of subgroups whose shadow prices increase. We also show that the increase is due to training agencies enrolling at the margin weaker members, in terms of performance, of that subgroup.performance measurement, cream-skimming, enrolment incentives, bureaucrat behavior, public organizations

Curbing cream-skimming: Evidence on enrolment incentives

Using data from a large, U.S. federal job training program, we investigate whether enrolment incentives that exogenously vary the ‘shadow prices’ for serving different demographic subgroups of clients influence case workers’ intake decisions. We show that case workers enroll more clients from subgroups whose shadow prices increase but select at the margin weaker-performing members from those subgroups. We conclude that enrolment incentives curb cream-skimming across subgroups leaving a residual potential for cream-skimming within a subgroup.Performance measurement, cream-skimming, enrolment incentives, bureaucrat behavior, public organizations

Current Trends and New Challenges of Databases and Web Applications for Systems Driven Biological Research

Dynamic and rapidly evolving nature of systems driven research imposes special requirements on the technology, approach, design and architecture of computational infrastructure including database and Web application. Several solutions have been proposed to meet the expectations and novel methods have been developed to address the persisting problems of data integration. It is important for researchers to understand different technologies and approaches. Having familiarized with the pros and cons of the existing technologies, researchers can exploit its capabilities to the maximum potential for integrating data. In this review we discuss the architecture, design and key technologies underlying some of the prominent databases and Web applications. We will mention their roles in integration of biological data and investigate some of the emerging design concepts and computational technologies that are likely to have a key role in the future of systems driven biomedical research

Inverse Association between High Blood 25-Hydroxyvitamin D Levels and Diabetic Retinopathy in a Representative Korean Population

Purpose To investigate the association between 25-hydroxyvitamin D and diabetic retinopathy (DR). Methods: A population-based cross-sectional study using a nation-wide, systemically stratified, multistage, clustered sampling method included a total of 18,363 subjects aged ≥40 years who participated in the Korean National Health and Nutrition Examination Survey during 2008–2012. All participants participated in standardized interviews, blood 25-hydroxyvitamin D level evaluations, and comprehensive ophthalmic examinations. Seven standard retinal fundus photographs were obtained from both eyes after pupil dilatation. DR was graded according to the modified Airlie House classification system. Results: The blood 25-hydroxyvitamin D levels were 19.2 ng/mL in men and 17.9 ng/mL in women. After adjusting for potential confounders, including age, sex, diabetes duration, hemoglobin A1c levels, and hypertension, the odds ratios (OR) for any DR and proliferative DR among men decreased significantly in the highest blood 25-hydroxyvitamin D level quintile relative to the lowest quintile (OR, 0.37; 95% confidence interval [CI], 0.18–0.76; P for trend = 0.004 and OR, 0.15; 95% CI, 0.03–0.83; P for trend = 0.043). Conclusions: This study provides the first epidemiologic findings of the inverse relationships of blood 25-hydroxyvitamin D levels with any DR and proliferative DR only in men. Considering anti-angiogenic and anti-fibrotic action of vitamin D, further studies including longitudinal and interventional analysis are warranted

An O.D.E. Framework of Distributed TD-Learning for Networked Multi-Agent Markov Decision Processes

The primary objective of this paper is to investigate distributed ordinary differential equation (ODE) and distributed temporal difference (TD) learning algorithms for networked multi-agent Markov decision problems (MAMDPs). In our study, we adopt a distributed multi-agent framework where individual agents have access only to their own rewards, lacking insights into the rewards of other agents. Additionally, each agent has the ability to share its parameters with neighboring agents through a communication network, represented by a graph. Our contributions can be summarized in two key points: 1) We introduce novel distributed ODEs, inspired by the averaging consensus method in the continuous-time domain. The convergence of the ODEs is assessed through control theory perspectives. 2) Building upon the aforementioned ODEs, we devise new distributed TD-learning algorithms. A standout feature of one of our proposed distributed ODEs is its incorporation of two independent dynamic systems, each with a distinct role. This characteristic sets the stage for a novel distributed TD-learning strategy, the convergence of which can potentially be established using Borkar-Meyn theorem

Monitoring of multi-frequency polarization of gamma-ray bright AGNs

We started two observing programs with the Korean VLBI Network (KVN) monitoring changes in the flux density and polarization of relativistic jets in gamma-ray bright AGNs simultaneously at 22, 43, 86, 129 GHz. One is a single-dish weekly-observing program in dual polarization with KVN 21-m diameter radio telescopes beginning in 2011 May. The other is a VLBI monthly-observing program with the three-element VLBI network at an angular resolution range of 1.0--9.2 mas beginning in 2012 December. The monitoring observations aim to study correlation of variability in gamma-ray with that in radio flux density and polarization of relativistic jets when they flare up. These observations enable us to study the origin of the gamma-ray flares of AGNs.Comment: 4 pages, 4 figures, Proceedings of the conference "The innermost regions of relativistic jets and their magnetic fields", Granada, Spai

Calcium Uptake and Release through Sarcoplasmic Reticulum in the Inferior Oblique Muscles of Patients with Inferior Oblique Overaction

We characterized and compared the characteristics of Ca2+ movements through the sarcoplasmic reticulum of inferior oblique muscles in the various conditions including primary inferior oblique overaction (IOOA), secondary IOOA, and controls, so as to further understand the pathogenesis of primary IOOA. Of 15 specimens obtained through inferior oblique myectomy, six were from primary IOOA, 6 from secondary IOOA, and the remaining 3 were controls from enucleated eyes. Ryanodine binding assays were performed, and Ca2+ uptake rates, calsequestrins and SERCA levels were determined. Ryanodine bindings and sarcoplasmic reticulum Ca2+ uptake rates were significantly decreased in primary IOOA (p<0.05). Western blot analysis conducted to quantify calsequestrins and SERCA, found no significant difference between primary IOOA, secondary IOOA, and the controls. Increased intracellular Ca2+ concentration due to reduced sarcoplasmic reticulum Ca2+ uptake may play a role in primary IOOA

Ultimate strength performance of tankers associated with industry corrosion addition Practices

In the ship and offshore structure design, age-related problems such as corrosion damage, local denting, and fatigue damage are important factors to be considered in building a reliable structure as they have a significant influence on the residual structural capacity. In shipping, corrosion addition methods are widely adopted in structural design to prevent structural capacity degradation. The present study focuses on the historical trend of corrosion addition rules for ship structural design and investigates their effects on the ultimate strength performance such as hull girder and stiffened panel of double hull oil tankers. Three types of rules based on corrosion addition models, namely historic corrosion rules (pre-CSR), Common Structural Rules (CSR), and harmonised Common Structural Rules (CSR-H) are considered and compared with two other corrosion models namely UGS model, suggested by the Union of Greek Shipowners (UGS), and Time-Dependent Corrosion Wastage Model (TDCWM). To identib) the general trend in the effects of corrosion damage on the ultimate longitudinal strength performance, the corrosion addition rules are applied to four representative sizes of double hull oil tankers namely Panamax, Aframax, Suezmax, and VLCC. The results are helpful in understanding the trend of corrosion additions for tanker structures.11Ysciescopu

Improvement of Information Transfer Rates Using a Hybrid EEG-NIRS Brain-Computer Interface with a Short Trial Length: Offline and Pseudo-Online Analyses

Electroencephalography (EEG) and near-infrared spectroscopy (NIRS) are non-invasive neuroimaging methods that record the electrical and metabolic activity of the brain, respectively. Hybrid EEG-NIRS brain-computer interfaces (hBCIs) that use complementary EEG and NIRS information to enhance BCI performance have recently emerged to overcome the limitations of existing unimodal BCIs, such as vulnerability to motion artifacts for EEG-BCI or low temporal resolution for NIRS-BCI. However, with respect to NIRS-BCI, in order to fully induce a task-related brain activation, a relatively long trial length (≥10 s) is selected owing to the inherent hemodynamic delay that lowers the information transfer rate (ITR; bits/min). To alleviate the ITR degradation, we propose a more practical hBCI operated by intuitive mental tasks, such as mental arithmetic (MA) and word chain (WC) tasks, performed within a short trial length (5 s). In addition, the suitability of the WC as a BCI task was assessed, which has so far rarely been used in the BCI field. In this experiment, EEG and NIRS data were simultaneously recorded while participants performed MA and WC tasks without preliminary training and remained relaxed (baseline; BL). Each task was performed for 5 s, which was a shorter time than previous hBCI studies. Subsequently, a classification was performed to discriminate MA-related or WC-related brain activations from BL-related activations. By using hBCI in the offline/pseudo-online analyses, average classification accuracies of 90.0 ± 7.1/85.5 ± 8.1% and 85.8 ± 8.6/79.5 ± 13.4% for MA vs. BL and WC vs. BL, respectively, were achieved. These were significantly higher than those of the unimodal EEG- or NIRS-BCI in most cases. Given the short trial length and improved classification accuracy, the average ITRs were improved by more than 96.6% for MA vs. BL and 87.1% for WC vs. BL, respectively, compared to those reported in previous studies. The suitability of implementing a more practical hBCI based on intuitive mental tasks without preliminary training and with a shorter trial length was validated when compared to previous studies