3,182 research outputs found

    Temperature measurements of falling droplets

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    The temperature of 225-ixm-dia I Introduction Vaporization in fuel sprays is a complex phenomenon involving heat and mass transfer in a dynamic mixture of droplets, fuel vapor, and ambient gas. Most workers in the field attempt to understand these processes in sprays by treating sprays as aggregates of individual drops, and therefore, understanding the processes that govern vaporization of individual fuel droplets becomes paramount. Many studies, both computational and empirical, of droplet vaporization have been performed, and reviews of the current understanding are available in the literature (Law, 1982; The vaporization of individual fuel droplets is generally studied photographically, a technique that yields only the droplet diameter Determination of the temperature of a droplet using thermocouples unavoidably perturbs both the droplet and the environment surrounding it and may alter the transfer of heat into or away from the droplet. In addition, suspended droplets are in physical contact with a support structure that may similarly make interpretation of the data uncertain. In this paper we describe the determination of the temperature of a decane droplet falling in a hot, relatively quiescent environment. The optical techniques described here can provide instantaneous, minimally perturbing measurement of even the surface temperatures of freely moving fuel droplets. The technique used to measure the droplet surface temperature is exciplex fluorescence thermometry (EFT), which exploits the temperature-dependent fluorescence resulting from the reaction of an excited dopant molecule to form a

    Neuromuscular Adaptions Following a Daily Strengthening Exercise in Individuals with Rotator Cuff Related Shoulder Pain: A Pilot Case-Control Study

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    Background: The goal of therapeutic exercise is to facilitate a neuromuscular response by increasing or decreasing muscular activity in order to reduce pain and improve function. It is not clear what dosage of exercise will create a neuromuscular response. Purpose: The purpose of this study was to assess the effects following a three-week home program of a daily single exercise, the prone horizontal abduction exercise (PHA), on neuromuscular impairments of motor control as measured by scapular muscle EMG amplitudes, strength, and secondarily outcomes of self-reported pain and function between individuals with and without subacromial pain syndrome. Study Design: Prospective Case-Control, Pilot Study. Methods: Twenty-five individuals participated; eleven with shoulder pain during active and resistive motions (Penn Shoulder Score: 77 ± 11) and 14 matched healthy controls (Penn Shoulder Score: 99 ± 27) (p \u3c 0.001). Participants underwent baseline and follow up testing at three weeks including surface electromyography (EMG) of the serratus anterior, upper, and lower trapezius of the involved (painful group) or matched shoulder (control group) during an elevation task and maximal isometric shoulder strength testing. All participants were instructed in a PHA exercise to be performed daily (3 sets; 10 reps). Subjects logged daily exercise adherence. Neuromuscular adaptations were defined by changes in EMG amplitudes (normalized to MVIC) of serratus anterior, upper trapezius, and lower trapezius and strength. Secondary outcomes of self-reported pain and function were also compared between groups following the three-week intervention. Results: After three weeks of a daily PHA exercise, the painful group demonstrated a greater decrease in baseline-elevated EMG amplitudes in the lower trapezius by 7% (95%CI 2.6-11%) during the concentric phase of the overhead lifting task (p 0.006). EMG amplitudes of the healthy control group did not change at three-week follow-up. Additionally, the change in serratus anterior mean EMG amplitude in the painful group -1.6% (IQR -22.9 to 0.8%) was significantly greater (p 0.033) than the healthy group change score, 2.5% (IQR -2.3 to 5.7%) during the eccentric phase (p 0.034). While the painful group was weaker in abduction and flexion at baseline and at follow up, both groups had a significant increase in all strength measures (p≤0.014). Concurrent with increased strength and normalizing EMG amplitudes, the painful group significantly improved on the Penn Shoulder Score with a mean change 9.8 points (95%CI 7.0, 12.6) (p \u3c 0.001). Conclusion: In this pilot case-control study, a single home exercise performed daily for three weeks demonstrated neuromuscular adaptations with improvements in muscle activity and strength. These were concurrent with modest, yet significant improvements pain and function in individuals with mild rotator cuff related shoulder pain. Level of Evidence: 3

    Promoter of a eukaryotic tRNAPro gene is composed of tree noncontiguous regions.

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    Appropriate Practices in College/University Physical Activity Instructional Programs

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    This session will introduce the audience to a new NASPE document that supports basic instructional programming at the college and university level. Based on NASPE’s former K-12 Appropriate Practice documents, this document will serve as an advocacy document for the importance of quality programming at the college/university level. Come and preview this new document

    Fine-tuned Sentiment Analysis of COVID-19 Vaccine-Related Social Media Data: Comparative Study

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    This study investigated and compared public sentiment related to COVID-19 vaccines expressed on two popular social media platforms, Reddit and Twitter, harvested from January 1, 2020, to March 1, 2022. To accomplish this task, we created a fine-tuned DistilRoBERTa model to predict sentiments of approximately 9.5 million Tweets and 70 thousand Reddit comments. To fine-tune our model, our team manually labeled the sentiment of 3600 Tweets and then augmented our dataset by the method of back-translation. Text sentiment for each social media platform was then classified with our fine-tuned model using Python and the Huggingface sentiment analysis pipeline. Our results determined that the average sentiment expressed on Twitter was more negative (52% positive) than positive and the sentiment expressed on Reddit was more positive than negative (53% positive). Though average sentiment was found to vary between these social media platforms, both displayed similar behavior related to sentiment shared at key vaccine-related developments during the pandemic. Considering this similar trend in shared sentiment demonstrated across social media platforms, Twitter and Reddit continue to be valuable data sources that public health officials can utilize to strengthen vaccine confidence and combat misinformation. As the spread of misinformation poses a range of psychological and psychosocial risks (anxiety, fear, etc.), there is an urgency in understanding the public perspective and attitude toward shared falsities. Comprehensive educational delivery systems tailored to the population's expressed sentiments that facilitate digital literacy, health information-seeking behavior, and precision health promotion could aid in clarifying such misinformation.Comment: 11 Pages, 5 Figures, and 1 Tabl

    Exploring celebrity influence on public attitude towards the COVID-19 pandemic: social media shared sentiment analysis

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    The COVID-19 pandemic has introduced new opportunities for health communication, including an increase in the public use of online outlets for health-related emotions. People have turned to social media networks to share sentiments related to the impacts of the COVID-19 pandemic. In this paper we examine the role of social messaging shared by Persons in the Public Eye (i.e. athletes, politicians, news personnel) in determining overall public discourse direction. We harvested approximately 13 million tweets ranging from 1 January 2020 to 1 March 2022. The sentiment was calculated for each tweet using a fine-tuned DistilRoBERTa model, which was used to compare COVID-19 vaccine-related Twitter posts (tweets) that co-occurred with mentions of People in the Public Eye. Our findings suggest the presence of consistent patterns of emotional content co-occurring with messaging shared by Persons in the Public Eye for the first two years of the COVID-19 pandemic influenced public opinion and largely stimulated online public discourse. We demonstrate that as the pandemic progressed, public sentiment shared on social networks was shaped by risk perceptions, political ideologies and health-protective behaviours shared by Persons in the Public Eye, often in a negative light.Comment: 7 Pages, 4 Figure

    Comparison of engagement and emotional responses of older and younger adults interacting with 3D cultural heritage artefacts on personal devices

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    The availability of advanced software and less expensive hardware allows museums to preserve and share artefacts digitally. As a result, museums are frequently making their collections accessible online as interactive, 3D models. This could lead to the unique situation of viewing the digital artefact before the physical artefact. Experiencing artefacts digitally outside of the museum on personal devices may affect the user's ability to emotionally connect to the artefacts. This study examines how two target populations of young adults (18–21 years) and the elderly (65 years and older) responded to seeing cultural heritage artefacts in three different modalities: augmented reality on a tablet, 3D models on a laptop, and then physical artefacts. Specifically, the time spent, enjoyment, and emotional responses were analysed. Results revealed that regardless of age, the digital modalities were enjoyable and encouraged emotional responses. Seeing the physical artefacts after the digital ones did not lessen their enjoyment or emotions felt. These findings aim to provide an insight into the effectiveness of 3D artefacts viewed on personal devices and artefacts shown outside of the museum for encouraging emotional responses from older and younger people

    In Solidarity

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    This edition of Next Page is a departure from our usual question and answer format with a featured campus reader. Instead, we asked speakers who participated in the College’s recent Student Solidarity Rally (March 1, 2017) to recommend readings that might further our understanding of the topics on which they spoke

    Reducing prescribing errors through creatinine clearance alert redesign

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    Background Literature has shown that computerized creatinine clearance alerts reduce errors during prescribing, and applying human factors principles may further reduce errors. Our objective was to apply human factors principles to creatinine clearance alert design and assess whether the redesigned alerts increase usability and reduce prescribing errors compared with the original alerts. Methods Twenty Veterans Affairs (VA) outpatient providers (14 physicians, 2 nurse practitioners, and 4 clinical pharmacists) completed 2 usability sessions in a counterbalanced study to evaluate original and redesigned alerts. Each session consisted of fictional patient scenarios with 3 medications that warranted prescribing changes because of renal impairment, each associated with creatinine clearance alerts. Quantitative and qualitative data were collected to assess alert usability and the occurrence of prescribing errors. Results There were 43% fewer prescribing errors with the redesigned alerts compared with the original alerts (P = .001). Compared with the original alerts, redesigned alerts significantly reduced prescribing errors for allopurinol and ibuprofen (85% vs 40% and 65% vs 25%, P = .012 and P = .008, respectively), but not for spironolactone (85% vs 65%). Nine providers (45%) voiced confusion about why the alert was appearing when they encountered the original alert design. When laboratory links were presented on the redesigned alert, laboratory information was accessed 3.5 times more frequently. Conclusions Although prescribing errors were high with both alert designs, the redesigned alerts significantly improved prescribing outcomes. This investigation provides some of the first evidence on how alerts may be designed to support safer prescribing for patients with renal impairment

    Cleaning verification by air/water impingement

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    This paper will discuss how the Kennedy Space Center intends to perform precision cleaning verification by Air/Water Impingement in lieu of chlorofluorocarbon-113 gravimetric nonvolatile residue analysis (NVR). Test results will be given that demonstrate the effectiveness of the Air/Water system. A brief discussion of the Total Carbon method via the use of a high temperature combustion analyzer will also be given. The necessary equipment for impingement will be shown along with other possible applications of this technology
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