Experimental analysis of different mail follow-up techniques within a national sample of hard-core nonrespondents

This paper is an initial endeavor to bridge the gap between powerful Deep Reinforcement Learning methodologies and the problem of exploration/coverage of unknown terrains. Within this scope, MarsExplorer, an openai-gym compatible environment tailored to exploration/coverage of unknown areas, is presented. MarsExplorer translates the original robotics problem into a Reinforcement Learning setup that various off-the-shelf algorithms can tackle. Any learned policy can be straightforwardly applied to a robotic platform without an elaborate simulation model of the robot’s dynamics to apply a different learning/adaptation phase. One of its core features is the controllable multi-dimensional procedural generation of terrains, which is the key for producing policies with strong generalization capabilities. Four different state-of-the-art RL algorithms (A3C, PPO, Rainbow, and SAC) are trained on the MarsExplorer environment, and a proper evaluation of their results compared to the average human-level performance is reported. In the follow-up experimental analysis, the effect of the multi-dimensional difficulty setting on the learning capabilities of the best-performing algorithm (PPO) is analyzed. A milestone result is the generation of an exploration policy that follows the Hilbert curve without providing this information to the environment or rewarding directly or indirectly Hilbert-curve-like trajectories. The experimental analysis is concluded by evaluating PPO learned policy algorithm side-by-side with frontier-based exploration strategies. A study on the performance curves revealed that PPO-based policy was capable of performing adaptive-to-the-unknown-terrain sweeping without leaving expensive-to-revisit areas uncovered, underlying the capability of RL-based methodologies to tackle exploration tasks efficiently.

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Risk of Parkinson’s disease after colectomy: longitudinal follow-up study using a national sample cohort

Journal of Neurology ◽

10.1007/s00415-019-09617-1 ◽

2019 ◽

Vol 267 (2) ◽

pp. 513-521 ◽

Cited By ~ 1

Author(s):

Young-Ju Kim ◽

Chang-Min Lee ◽

Seongheon Kim ◽

Jae-Won Jang ◽

Seo-Young Lee ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

National Sample ◽

Follow Up Study

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Light-Intensity Physical Activity and All-Cause Mortality

American Journal of Health Promotion ◽

10.4278/ajhp.150515-arb-882 ◽

2016 ◽

Vol 31 (4) ◽

pp. 340-342 ◽

Cited By ~ 35

Author(s):

Paul D. Loprinzi

Keyword(s):

Physical Activity ◽

Light Intensity ◽

Mortality Risk ◽

Weight Status ◽

Vigorous Physical Activity ◽

National Sample ◽

Poverty Level ◽

All Cause Mortality ◽

Intensity Physical Activity

Purpose. Research demonstrates that moderate-to-vigorous physical activity (MVPA) is associated with a reduced risk of all-cause mortality. Few studies have examined the effects of light-intensity physical activity on mortality. Therefore, the purpose of this study was to examine the association between objectively measured light-intensity physical activity and all-cause mortality risk. Design. Longitudinal. Setting. National Health and Nutrition Examination Survey 2003–2006 with follow-up through December 31, 2011. Subjects. Five thousand five hundred seventy-five U.S. adults. Measures. Participants wore an accelerometer for at least 4 days and completed questionnaires to assess sociodemographics and chronic disease information, with blood samples taken to assess biological markers. Follow-up mortality status was assessed via death certificate data from the National Death Index. Analysis. Cox proportional hazard model. Results. After adjusting for accelerometer-determined MVPA, age, gender, race-ethnicity, cotinine, weight status, poverty level, C-reactive protein, and comorbid illness, for every 60-minute increase in accelerometer-determined light-intensity physical activity, participants had a 16% reduced hazard of all-cause mortality (hazard ratio = .84; 95% confidence interval: .78–.91; p < .001). Conclusion. In this national sample of U.S. adults, light-intensity physical activity was inversely associated with all-cause mortality risk, independent of age, MVPA, and other potential confounders. In addition to MVPA, promotion of light-intensity physical activity is warranted.

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Chronic rhinosinusitis increases the risk of hemorrhagic and ischemic stroke: A longitudinal follow-up study using a national sample cohort

PLoS ONE ◽

10.1371/journal.pone.0193886 ◽

2018 ◽

Vol 13 (3) ◽

pp. e0193886 ◽

Cited By ~ 3

Author(s):

Woo Hyun Lee ◽

Jeong-Whun Kim ◽

Jae-Sung Lim ◽

Il Gyu Kong ◽

Hyo Geun Choi

Keyword(s):

Ischemic Stroke ◽

Chronic Rhinosinusitis ◽

National Sample ◽

Follow Up Study

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A comparison of mortality between patients treated with hemodialysis and peritoneal dialysis.

Journal of the American Society of Nephrology ◽

10.1681/asn.v62177 ◽

1995 ◽

Vol 6 (2) ◽

pp. 177-183

Author(s):

W E Bloembergen ◽

F K Port ◽

E A Mauger ◽

R A Wolfe

Keyword(s):

Peritoneal Dialysis ◽

Mortality Rate ◽

High Mortality ◽

Epidemiologic Study ◽

National Sample ◽

National Study ◽

Dialysis Patients ◽

All Cause Mortality ◽

Males And Females

Patients with ESRD treated with dialysis have a high mortality rate. Controversy exists as to whether this high mortality rate is affected by modality choice. The purpose of this epidemiologic study was to compare mortality in prevalent hemodialysis-treated (HD) and peritoneal dialysis-treated (PD) patients in a large national sample, adjusting for demographic characteristics. Data were obtained from the U.S. Renal Data System for patients prevalent on January 1 of the years 1987, 1988, and 1989, each with 1 yr of follow-up. Patients were censored at transplantation. Death rates per 100 patient years were compared between HD and PD, adjusting for age, race, gender, cause of ESRD (diabetes versus nondiabetes) and < 1 yr or > 1 yr of prior ESRD, by the use of Poisson regression. There were 42,372 deaths occurring over 170,700 patient years at risk. On average, prevalent patients treated with PD had a 19% higher adjusted mortality risk (relative risk (RR) = 1.19; P < 0.001) than did those treated with HD. This risk was found to be insignificant (P > 0.05) and small for ages < 55 and increasingly large and significant for ages > 55 yr. It was accentuated in diabetics (RR = 1.38; P < 0.001) but was also present in nondiabetics (RR = 1.11; P < 0.001). Although present in both males and females, this risk was accentuated in females (RR = 1.30 versus 1.11; both P < 0.001). In this national study of prevalent U.S. dialysis patients, treatment assignment to PD was associated with a 19% higher all-cause mortality rate than HD.(ABSTRACT TRUNCATED AT 250 WORDS)

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