Short-lived signatures

A short-lived signature is a digital signature with one distinguishing feature: with the passage of time, the validity of the signature dissipates to the point where valid signatures are no longer distinguishable from simulated forgeries (but the signing key remains secure and reusable). This dissipation happens "naturally" after signing a message and does not require further involvement from the signer, verifi�er, or a third party. This thesis introduces several constructions built from sigma protocols and proof of work algorithms and a framework by which to evaluate future constructions. We also describe some applications of short-lived signatures and proofs in the domains of secure messaging and voting

The Influence Of Learning Styles On Student Perception And Satisfaction In A Highly Collaborative Team Taught Course

Team teaching an undergraduate business capstone course has the potential of providing students with an enhanced learning experience in a number of ways. This study examines the relationship between faculty and student learning styles and their impact on student perception and satisfaction in a highly collaborative team taught undergraduate business capstone course.The faculty members as well as students in the control and experimental groups completed Kolb’s Learning Style Inventory. Research data revealed that the learning styles of the three member faculty team influenced student perception of course material and their overall level of satisfaction. This study suggests that the diversity of faculty learning styles present in the classroom provides a common connection with groups of students with the same or similar learning style which enhances the learning environment. In addition, the highly collaborative team teaching model created an environment of cohesion and commitment among the faculty members

An Examination Of The Impact Of Team Teaching On Student Learning Outcomes And Student Satisfaction In Undergraduate Business Capstone Courses

This study examines the impact of team teaching on student learning outcomes and student satisfaction in the context of three undergraduate business capstone courses. Students in three undergraduate business capstone course sections were selected for the study. One section of the capstone course was taught using a team delivery model and the other two sections were taught by a single faculty member. The study found that students’ GPA had a significant correlation with their performance in the team taught course. The data suggests that students with a GPA of less than 3.28 in the team taught course, performed higher than would be expected. Moreover their individual performance scores appeared to be higher than the regression line would predict. Students in the team taught course also were satisfied with the team teaching method

What are the Actual Flaws in Important Smart Contracts (and How Can We Find Them)?

An important problem in smart contract security is understanding the likelihood and criticality of discovered, or potential, weaknesses in contracts. In this paper we provide a summary of Ethereum smart contract audits performed for 23 professional stakeholders, avoiding the common problem of reporting issues mostly prevalent in low-quality contracts. These audits were performed at a leading company in blockchain security, using both open-source and proprietary tools, as well as human code analysis performed by professional security engineers. We categorize 246 individual defects, making it possible to compare the severity and frequency of different vulnerability types, compare smart contract and non-smart contract flaws, and to estimate the efficacy of automated vulnerability detection approaches

Taxonomy of USA East Coast Fishing Communities in Terms of Social Vulnerability and Resilience

Increased concern with the impacts that changing coastal environments can have on coastal fishing communities led to a recent effort by NOAA Fisheries social scientists to develop a set of indicators of social vulnerability and resilience for the U.S. Southeast and Northeast coastal communities. A goal of the NOAA Fisheries social vulnerability and resilience indicator program is to support time and cost effective use of readily available data in furtherance of both social impact assessments of proposed changes to fishery management regulations and climate change adaptation planning. The use of the indicators to predict the response to change in coastal communities would be enhanced if community level analyses could be grouped effectively. This study examines the usefulness of combining 1130 communities into 35 relevant subgroups by comparing results of a numerical taxonomy with data collected by interview methods, a process herein referred to as “ground-truthing.” The validation of the taxonomic method by the method of ground-truthing indicates that the clusters are adequate to be used to select communities for in-depth research

Indicators of Climate Change and Social Vulnerability in Fishing Dependent Communities Along the Eastern and Gulf Coasts of the U.S. Marine Policy

Changing climatic conditions are affecting the relationship between fishing communities and the marine resources they depend on. This shift will require an adaptive response on the part of policy makers and fishery managers. In the U.S., the National Oceanic and Atmospheric Administration (NOAA) established, in its fisheries agency (NOAA Fisheries), a set of social indicators of fishing community vulnerability and resilience to evaluate the impacts of changes in fishery management regimes. These indicators enhance the analytical capabilities within NOAA Fisheries for conducting fisheries social impact assessments and informing ecosystem-based fishery management. Building on the existing Community Social Vulnerability Indicators (CSVIs), new measures of climate change vulnerability are defined for the U.S. Eastern and Gulf coasts. These new indicators are used to assess the impact of sea level rise on critical commercial fishing infrastructure and the dependence of communities on species identified as vulnerable to the effects of climate change. Examples are provided in this article to demonstrate the utility of these new indicators to policy makers and the NOAA strategic goal for building resilient coastal communities that are environmentally and economically sustainable. Integration of CSVIs and the new climate change vulnerability indices highlight community needs for unique solutions in order to adapt to environmental and social changes and maintain their well-being

Estimating adolescent sleep patterns: parent reports versus adolescent self-report surveys, sleep diaries, and actigraphy

In research and clinical contexts, parent reports are often used to gain information about the sleep patterns of their adolescents; however, the degree of concordance between parent reports and adolescent-derived measures is unclear. The present study compares parent estimates of adolescent sleep patterns with adolescent self-reports from surveys and sleep diaries, together with actigraphy. Methods: A total of 308 adolescents (59% male) aged 13–17 years completed a school sleep habits survey during class time at school, followed by a 7-day sleep diary and wrist actigraphy. Parents completed the Sleep, Medical, Education and Family History Survey. Results: Parents reported an idealized version of their adolescent’s sleep, estimating significantly earlier bedtimes on both school nights and weekends, significantly later wake times on weekends, and significantly more sleep than either the adolescent self-reported survey, sleep diary, or actigraphic estimates. Conclusion: Parent reports indicate that the adolescent averages a near-optimal amount of sleep on school nights and a more than optimal amount of sleep on weekends. However, adolescent-derived averages indicate patterns of greater sleep restriction. These results illustrate the importance of using adolescent-derived estimates of sleep patterns in this age group and the importance of sleep education for both adolescents and their parents

Cigarette smoking increases the development of intimal hyperplasia after vascular injury

Purpose: Our purpose was to determine whether exposure to cigarette smoke increases the development of intimal hyperplasia (IH) after vascular injury.Methods: Sixteen adult male Sprague-Dawley rats underwent standardized balloon catheter injury of the left common carotid artery. For 4 weeks before and 4 weeks after injury, animals in the experimental group (n=8) were exposed to cigarette smoke with an automated vacuum pump device. Animals in the control group (n=8) were restrained in the smoking device for an identical amount of time and underwent arterial injury at 4 weeks but were not exposed to cigarette smoke. Carotid arteries were perfusion-fixed in vivo, prepared as histologic cross sections, and stained for elastin. IH was measured by planimetry and is reported both as the absolute area of IH and as the ratio (IH/IEL) of the absolute area of IH to the normalized area enclosed by the internal elastic lamina (expressed as a percent).Results: The absolute area of IH was 2.09±0.34 for the experimental group compared with 0.94±0.25 for the control group; mean IH/IEL was 43.7%±7.1% for the experimental group versus 17.7%±4.7% for the control group (p<0.05, two-tailed unpaired t test).Conclusions: Inhalation of cigarette smoke increases the development of intimal hyperplasia in a rat model of balloon catheter arterial injury