IST Austria Technical Report

We consider the problem of expected cost analysis over nondeterministic probabilistic programs, which aims at automated methods for analyzing the resource-usage of such programs. Previous approaches for this problem could only handle nonnegative bounded costs. However, in many scenarios, such as queuing networks or analysis of cryptocurrency protocols, both positive and negative costs are necessary and the costs are unbounded as well. In this work, we present a sound and efficient approach to obtain polynomial bounds on the expected accumulated cost of nondeterministic probabilistic programs. Our approach can handle (a) general positive and negative costs with bounded updates in variables; and (b) nonnegative costs with general updates to variables. We show that several natural examples which could not be handled by previous approaches are captured in our framework. Moreover, our approach leads to an efficient polynomial-time algorithm, while no previous approach for cost analysis of probabilistic programs could guarantee polynomial runtime. Finally, we show the effectiveness of our approach by presenting experimental results on a variety of programs, motivated by real-world applications, for which we efficiently synthesize tight resource-usage bounds

Psychology and Sustainability, Homo Technicusand Slow Tech

Psychology and Sustainability, Homo Technicus and Slow TechIn previous issues of Visions for Sustainabilitywe have often published papers that consider the relationship between psychology and sustainability. On the one hand, researchers have examined various aspects of the incompatibility between how human societies and individuals behave in order to satisfy their needs and their desires and the natural processes that are essential for maintaining ecological balance and integrity, both for the people themselves and the environments they inhabit. Problems of sustainability are clearly related to human behaviours and therefore are a part of the psychological sphere. Studies have often focused on examining ways of promoting pro-environmental and reducing anti-environmental behaviours

Association Between Objectively Sleep Pattern and Obesity in the Elderly

Background: Previous studies on the relationship between sleep patterns and obesity in the elderly are limited and have conflicting results. Moreover, few studies have measured sleep patterns objectively. In this study, we investigated objective sleep patterns and their relationship with obesity in the elderly in Tehran, Iran.Methods: In this cross-sectional study, 88 elderly (≥60 years old) who were members of health homes of zone 5 in Tehran, Iran, were included by simple random sampling method in 2014. Sleep patterns were objectively assessed using waist actigraphy for a mean of 4.3 ± 1.7 days). Height, weight, and waist circumference (WC) were measured by standard methods and body mass index (BMI) was calculated. Data entry and statistical analyses were performed using SPSS version 21.Results: Mean actigraphy-assessed sleep duration, sleep efficiency (percentage of time in bed spent sleeping), and sleep latency (time required to fall asleep) were 427 ± 62 min, 71.3 ± 18%, and 14.2 ± 3.8 min, respectively. A negative relationship was found between BMI and sleep duration (r = −0.2, p = 0.03), BMI and sleep efficiency (r = −0.3, p=0.01), and WC and sleep efficiency (r = −0.2, p = 0.04). Also, a positive association was observed between BMI and sleep latency (r = 0.4, p = 0.006).Conclusions: In the elderly, actigraphy-assessed sleep duration was associated with obesity and the sleep efficiency was poor in obese participants. It seems that sleep patterns and BMI are correlated with each other. However, there is a need for prospective studies to affirm causal relationships between these constructs

Association Between Objectively Sleep Pattern and Obesity in the Elderly

Background: Previous studies on the relationship between sleep patterns and obesity in the elderly are limited and have conflicting results. Moreover, few studies have measured sleep patterns objectively. In this study, we investigated objective sleep patterns and their relationship with obesity in the elderly in Tehran, Iran.Methods: In this cross-sectional study, 88 elderly (≥60 years old) who were members of health homes of zone 5 in Tehran, Iran, were included by simple random sampling method in 2014. Sleep patterns were objectively assessed using waist actigraphy for a mean of 4.3 ± 1.7 days). Height, weight, and waist circumference (WC) were measured by standard methods and body mass index (BMI) was calculated. Data entry and statistical analyses were performed using SPSS version 21.Results: Mean actigraphy-assessed sleep duration, sleep efficiency (percentage of time in bed spent sleeping), and sleep latency (time required to fall asleep) were 427 ± 62 min, 71.3 ± 18%, and 14.2 ± 3.8 min, respectively. A negative relationship was found between BMI and sleep duration (r = −0.2, p = 0.03), BMI and sleep efficiency (r = −0.3, p=0.01), and WC and sleep efficiency (r = −0.2, p = 0.04). Also, a positive association was observed between BMI and sleep latency (r = 0.4, p = 0.006).Conclusions: In the elderly, actigraphy-assessed sleep duration was associated with obesity and the sleep efficiency was poor in obese participants. It seems that sleep patterns and BMI are correlated with each other. However, there is a need for prospective studies to affirm causal relationships between these constructs