167 research outputs found
Extending Scratch: New pathways into programming
We present the Scratch extension system, a toolkit that enables anyone to extend the vocabulary of the visual Scratch programming language through custom programming blocks written in JavaScript. The extension system is designed to (i) enable innovating on the Scratch programming language itself, in addition to innovating with it through projects, and (ii) enable the creation of new interest-driven pathways into Scratch programming. In this paper, we describe some of the prior work done in this space, our design and implementation, open questions and challenges, and some preliminary outcomes.National Science Foundation (U.S.) (grant number 1002713)National Science Foundation (U.S.) (grant number 1027848)National Science Foundation (U.S.) (grant number 1417952
A longitudinal and experimental study of the impact of knowledge on the bases of institutional trust
This study examined a knowledge-centered theory of institutional trust development. In the context of trust in water regulatory institutions, the moderating impact of knowledge was tested to determine if there were longitudinal changes in the bases of institutional trust as a function of increases in knowledge about a target institution. We hypothesized that as people learn about an institution with which they were previously unfamiliar, they begin to form more nuanced perceptions, distinguishing the new institution from other institutions and relying less upon their generalized trust to estimate their trust in that institution. Prior to having specific, differential information about a new institution, we expected institutional trust to be a function of generalized trust variables such as dispositional trust and trust in government. The longitudinal experiment involved 185 college students randomly assigned to one of three information conditions. Every 3 months for 15 months, participants read information about water regulatory institutions or a control institution. At each time point, participants reported their trust in and perceptions of the trust- and distrust-worthiness of the water regulatory institutions. Participants also completed measures of knowledge of water regulatory institutions, dispositional trust, and governmental trust. Our manipulation check indicated that, as expected, those in the experimental group increased in subjective knowledge of water regulatory institutions to a greater extent than those in the control condition. Consistent with our hypotheses, there was some evidence that, compared to the control group, the experimental group relied less on their general trust in government as a basis for their trust in water regulatory institutions. However, contrary to our hypotheses, there was no evidence the experimental group relied less on dispositional trust as a basis for institutional trust. There also was some evidence the experimental group\u27s trust in water regulatory institutions was less affected by fluctuations of trustworthiness (but not distrustworthiness) perceptions over time. This suggests that knowledge results in the development of more stable institutional trust attitudes, but that trustworthiness and distrustworthiness perceptions may operate somewhat differently when impacting trust in specific institutions
Lessons Learned from the Development and Flight of the First Miniature Tethered Electrodynamics Experiment (MiTEE-1)
The Miniature Tether Electrodynamics Experiment (MiTEE) CubeSat team is a technological advancement project intended to evaluate technology for Electrodynamic Tether (EDT) propulsion on very small pico- and femto-satellite platforms. MiTEE is demonstrating this through a series of missions starting with MiTEE-1, a 3U CubeSat designed to characterize the electron current collection behavior of a biased, simulated picosat mounted at the end of a 1-meter deployable boom. In addition, a miniaturized Langmuir probe electronics board was flown to characterize the ambient plasma environment. MiTEE-1 was launched successfully with Virgin Orbit’s Launch Demo 2 flight on NASA’s 20th Educational Launch of Nanosatellites (ELaNa XX) mission, January 17, 2021
A longitudinal and experimental study of the impact of knowledge on the bases of institutional trust
This study examined a knowledge-centered theory of institutional trust development. In the context of trust in water regulatory institutions, the moderating impact of knowledge was tested to determine if there were longitudinal changes in the bases of institutional trust as a function of increases in knowledge about a target institution. We hypothesized that as people learn about an institution with which they were previously unfamiliar, they begin to form more nuanced perceptions, distinguishing the new institution from other institutions and relying less upon their generalized trust to estimate their trust in that institution. Prior to having specific, differential information about a new institution, we expected institutional trust to be a function of generalized trust variables such as dispositional trust and trust in government. The longitudinal experiment involved 185 college students randomly assigned to one of three information conditions. Every 3 months for 15 months, participants read information about water regulatory institutions or a control institution. At each time point, participants reported their trust in and perceptions of the trust- and distrust-worthiness of the water regulatory institutions. Participants also completed measures of knowledge of water regulatory institutions, dispositional trust, and governmental trust. Our manipulation check indicated that, as expected, those in the experimental group increased in subjective knowledge of water regulatory institutions to a greater extent than those in the control condition. Consistent with our hypotheses, there was some evidence that, compared to the control group, the experimental group relied less on their general trust in government as a basis for their trust in water regulatory institutions. However, contrary to our hypotheses, there was no evidence the experimental group relied less on dispositional trust as a basis for institutional trust. There also was some evidence the experimental group\u27s trust in water regulatory institutions was less affected by fluctuations of trustworthiness (but not distrustworthiness) perceptions over time. This suggests that knowledge results in the development of more stable institutional trust attitudes, but that trustworthiness and distrustworthiness perceptions may operate somewhat differently when impacting trust in specific institutions
Results of a Feasibility Randomized Controlled Trial (RCT) of the Toolkit for Optimal Recovery (TOR): A Live Video Program to Prevent Chronic Pain in At-Risk Adults with Orthopedic Injuries
Background: Orthopedic injuries are the leading cause of hospital admissions in the USA, and many of these patients transition into chronic pain. Currently, there are no evidence-based interventions targeting prevention of chronic pain in patients with orthopedic injuries. We iteratively developed a four-session intervention “The Toolkit for Optimal Recovery” (TOR) which we plan to subsequently test for efficacy in a phase III hybrid efficacy-effectiveness multi-site clinical trial. In order to prevent methodological weaknesses in the subsequent trial, we conducted a feasibility pilot to evaluate the TOR delivered via secure live video versus usual care (UC) in patients with orthopedic injuries from an urban, level I trauma clinic, who screen in as at risk for chronic pain and disability. We tested the feasibility of recruitment, acceptability of screening, and randomization methods; acceptability of the intervention, treatment adherence, and treatment fidelity; satisfaction with the intervention; feasibility of the assessment process at all time points; acceptability of outcome measures for the definitive trial; and within-treatment effect sizes.
Methods: We aimed to recruit 50–60 participants, randomize, and retain them for ~ 4 months. Assessments were done electronically via REDCap at baseline, post-intervention (approximately 5 weeks after baseline), and 3 months later. We followed procedures we intend to implement in the full-scale hybrid efficacy-effectiveness trial.
Results: We recruited 54 participants and found that randomization and data collection procedures were generally acceptable. The majority of participants were white, educated, and employed. Warm hand-off referrals were more effective than research assistants directly approaching patients for participation without their providers’ engagement. Feasibility of recruitment, acceptability of screening, and randomization were good. Satisfaction with the program, adherence to treatment sessions, and treatment fidelity were all high. There were no technical issues associated with the live video delivery of the TOR. There was minimal missing data and outcome measures were deemed appropriate. Effect sizes for improvement after participation in TOR were moderate to large. There were many lessons learned for future trials.
Conclusions: This study provided evidence of the feasibility of the planned hybrid efficacy-effectiveness trial design when implemented at our home institution. Establishing feasibility of the intervention and study procedures at other trauma centers with more diverse patient populations and different clinical practices is required before a multi-site phase III efficacy-effectiveness trial.
Trial registration: ClinicalTrials.gov ID: NCT03405610. Registered on January 28, 2018—retrospectively registered
The Impact of Mobile DIS and Rank-Decreased Attacks in Internet of Things Networks
With a predicted 50 billion devices by the end of 2020, the Internet of things has grown exponentially in the last few years. This growth has seen an increasing demand for mobility support in low power and lossy sensor networks, a type of network characterized by several limitations in terms of their resources including CPU, memory and batter, causing manufactures to push products out to the market faster, without the necessary security features. IoT networks rely on the Routing Protocol for Low Power and Lossy Network (RPL) for communication, designed by the Internet Engineering Task Force (IETF). This protocol has been proven to be efficient in relation to the handling of routing in such constrained networks, However, research studies revealed that RPL was inherently designed for static networks, indicating poor handling of mobile or dynamic topologies which is worsen when introducing mobile attacker. In this paper, two IoT routing attacks are evaluated under a mobile attacker with the aim of providing a critical evaluation of the impact the attacks have on the network in comparison to the case with static attacker. The first attack is the Rank attack in which the attacker announces false routing information to its neighbour attracting them to forward their data via the attacker. The second attack is the DIS attack in which the attacker floods the network with DIS messages triggering them to reset their transmission timers and sending messages more frequently. The comparison were conducted in terms of average power consumption and also the packet delivery ratio (PDR). Based on the results collected from the simulations, it was established that when an attacking node is mobile, there’s an average increase of 36.6 in power consumption and a decrease of 14 for packet delivery ratios when compared to a static attacking node
Attitudes and Performance: An Analysis of Russian Workers
This paper investigates the relationship between locus of control and performance among Russian employees, using survey data collected at 28 workplaces in 2002 in Taganrog and at 47 workplaces in 2003 in Ekaterinburg. We develop a measure that allows us to categorize the Russian employees participating in our survey as exhibiting an internal or external locus of control. We then assess the extent to which there are significant differences between “internals” and “externals” in work-related attitudes that may affect performance. In particular, we focus on (1) attitudes about outcomes associated with hard work, (2) level of job satisfaction, (3) expectation of receiving a desired reward, and (4) loyalty to and involvement with one’s organization. In each case we identify where gender and generational differences emerge. Our main objective is to determine whether Russian employees who exhibit an internal locus of control perform better than employees with an external locus of control. Our performance measures include earnings, expected promotions, and assessments of the quantity and quality of work in comparison to others at the same organization doing a similar job. Controlling for a variety of worker characteristics, we find that (1) individuals who exhibit an internal locus of control perform better, but this result is not always statistically significant; (2) even among “internals,” women earn significantly less than men and have a much lower expectation of promotion; (3) even among “internals,” experience with unemployment has a negative influence on performance.http://deepblue.lib.umich.edu/bitstream/2027.42/40144/3/wp758.pd
Effects of anthropogenic emissions on aerosol formation from isoprene and monoterpenes in the southeastern United States
Secondary organic aerosol (SOA) constitutes a substantial fraction of fine particulate matter and has important impacts on climate and human health. The extent to which human activities alter SOA formation from biogenic emissions in the atmosphere is largely undetermined. Here, we present direct observational evidence on the magnitude of anthropogenic influence on biogenic SOA formation based on comprehensive ambient measurements in the southeastern United States (US). Multiple high-time-resolution mass spectrometry organic aerosol measurements were made during different seasons at various locations, including urban and rural sites in the greater Atlanta area and Centreville in rural Alabama. Our results provide a quantitative understanding of the roles of anthropogenic SO(2) and NO(x) in ambient SOA formation. We show that isoprene-derived SOA is directly mediated by the abundance of sulfate, instead of the particle water content and/or particle acidity as suggested by prior laboratory studies. Anthropogenic NO(x) is shown to enhance nighttime SOA formation via nitrate radical oxidation of monoterpenes, resulting in the formation of condensable organic nitrates. Together, anthropogenic sulfate and NO(x) can mediate 43–70% of total measured organic aerosol (29–49% of submicron particulate matter, PM(1)) in the southeastern US during summer. These measurements imply that future reduction in SO(2) and NO(x) emissions can considerably reduce the SOA burden in the southeastern US. Updating current modeling frameworks with these observational constraints will also lead to more accurate treatment of aerosol formation for regions with substantial anthropogenic−biogenic interactions and consequently improve air quality and climate simulations
'To live and die [for] Dixie': Irish civilians and the Confederate States of America
Around 20,000 Irishmen served in the Confederate army in the Civil War. As a result, they left behind, in various Southern towns and cities, large numbers of friends, family, and community leaders. As with native-born Confederates, Irish civilian support was crucial to Irish participation in the Confederate military effort. Also, Irish civilians served in various supporting roles: in factories and hospitals, on railroads and diplomatic missions, and as boosters for the cause. They also, however, suffered in bombardments, sieges, and the blockade. Usually poorer than their native neighbours, they could not afford to become 'refugees' and move away from the centres of conflict. This essay, based on research from manuscript collections, contemporary newspapers, British Consular records, and Federal military records, will examine the role of Irish civilians in the Confederacy, and assess the role this activity had on their integration into Southern communities. It will also look at Irish civilians in the defeat of the Confederacy, particularly when they came under Union occupation. Initial research shows that Irish civilians were not as upset as other whites in the South about Union victory. They welcomed a return to normalcy, and often 'collaborated' with Union authorities. Also, Irish desertion rates in the Confederate army were particularly high, and I will attempt to gauge whether Irish civilians played a role in this. All of the research in this paper will thus be put in the context of the Drew Gilpin Faust/Gary Gallagher debate on the influence of the Confederate homefront on military performance. By studying the Irish civilian experience one can assess how strong the Confederate national experiment was. Was it a nation without a nationalism
Thoracolumbar injury classification and severity score: a new paradigm for the treatment of thoracolumbar spine trauma
BACKGROUND: Contemporary understanding of the biomechanics, natural history, and methods of treating thoracolumbar spine injuries continues to evolve. Current classification schemes of these injuries, however, can be either too simplified or overly complex for clinical use.
METHODS: The Spine Trauma Group was given a survey to identify similarities in treatment algorithms for common thoracolumbar injuries, as well as to identify characteristics of injury that played a key role in the decision-making process.
RESULTS: Based on the survey, the Spine Trauma Group has developed a classification system and an injury severity score (thoracolumbar injury classification and severity score, or TLICS), which may facilitate communication between physicians and serve as a guideline for treating these injuries. The classification system is based on the morphology of the injury, integrity of the posterior ligamentous complex, and neurological status of the patient. Points are assigned for each category, and the final total points suggest a possible treatment option.
CONCLUSIONS: The usefulness of this new system will have to be proven in future studies investigating inter- and intraobserver reliability, as well as long-term outcome studies for operative and nonoperative treatment methods
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