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Introduction: Anecdotal reports and limited reports suggest a possible link between activities involving rapid acceleration and retinal detachment. We present two novel such cases and review existing literature to investigate the plausibility of this association and delineate in what populations such an association may be more likely. Case Presentation: We report 2 cases of retinal detachment following roller coaster riding. The first, a 24-year-old woman with a family history of retinal detachment, presented with floaters after consecutive rides and was found to have an inferior temporal macula-sparing retinal detachment with associated retinal breaks. The second case, a 25-year-old female with a history of high myopia, presented with visual field defect and was found to have a macula-on retinal detachment with an accompanying tear at the edge of an area of lattice degeneration. Both were successfully treated with pneumatic retinopexy followed by laser retinopexy. Conclusion: Rapid acceleration/deceleration forces, such as those experienced on roller coasters, could potentially lead to retinal detachment. Structural predisposition is likely necessary for acceleration/deceleration injury to lead to retinal detachment, with all known cases having risk factors, including high myopia and positive family history. These same forces in eyes without structural predisposition have resulted in hemorrhage, but not detachment. [ABSTRACT FROM AUTHOR]

The use of teaching aids in learning can provide direct learning experiences to students so that learning becomes more meaningful. Students observe physics phenomena that occur and get physics data from these phenomena. The observed physics phenomena often happen very quickly, so it is impossible to record data manually. Therefore, a method is needed to facilitate data recording and analysis. One way to use a video-based laboratory (VBL) is by utilizing a tracker. This method allows for analyzing the objects contained in a video and displays the data in graphs and tables. This study aims to investigate the motion of objects using tracker video analysis on a mini-roller coaster tool. The video analyzed is a video of a solid ball-shaped object with a mass of 8.6 g moving along a roller-coaster trajectory. By tracking an object, physics data will be obtained to analyze acceleration and the law of conservation of mechanical energy. The analysis results match the experimental results and the physics concepts that apply to the roller coaster motion. [ABSTRACT FROM AUTHOR]

This study presents a rollercoaster activity including virtual reality and following the six-steps engineering design process. In the study, a real-life problem involving a rollercoaster accident was given to 12 pre-service science teachers first. The participants were then asked to imagine, plan, create, and test a rollercoaster without an impulsion or braking system that could prevent this kind of accident. The pre-service teachers worked in groups to design their rollercoaster in three 50-minute sessions. After designing their rollercoasters, the pre-service teachers were shown a rollercoaster video with VR glasses so that they could test their designs by noticing the faulty parts. After they improved their designs, each rollercoaster was evaluated by the researchers using the rubric. The activity is critical in providing pre-service science teachers with an example of integrating the STEM approach into their lessons and incorporating virtual reality in STEM education. The activity also can help students become entrepreneurial thinkers and understand how science is connected to other disciplines such as technology, mathematics, or engineering. The activity can also help students develop 21st-century skills such as collaboration, critical thinking, creativity, problem-solving, and analytical thinking. [ABSTRACT FROM AUTHOR]

The purpose of this study was to propose a model for estimating individual susceptibility to motion sickness by correlating measures of seated postural sway before exposure to a roller coaster movie displayed in a head-mounted display (HMD) with subjective ratings of visually induced motion sickness (VIMS). The participants were required to watch the content for 15 min, and seated center of pressure (sCOP) was measured using a force platform for 5 min before viewing. We developed a VIMS estimating model from 16 subjects and verified it on 15 subjects. SSQ scores for VIMS were strongly correlated with the area of sCOP, the main-to-minor ratio of the sCOP ellipse, and the total length of sCOP, respectively (r = 0.706, r = 0.555, and r = 0.622). When verifying the estimation model, the observed SSQ scores differed by 32.628 ± 29.749 from the expected SSQ scores, and both score sets were positively correlated (r = 0.622). The classification results between nil and mild, moderate, and severe groups for VIMS showed an accuracy of 0.74 using random under-sampling boost (RUSBoost). [ABSTRACT FROM AUTHOR]

The approach of the study is on singularity properties of timelike circular surfaces in Minkowski 3-space. A timelike circular surface is a one-parameter set of Lorentzian circles with stationary radius directing a non-null space curve, which acts as the spine curve, and it has symmetrical properties. In this study, we addressed timelike circular surfaces and gained their geometric and singularity properties such as Gaussian and mean curvatures, comparable with those of ruled surfaces. Consequently, we presented timelike roller coaster surfaces as a special class of timelike circular surfaces. Then, the conditions for timelike roller coaster surfaces to be flat or minimal surfaces are obtained. Meanwhile, we supported the results of the approach with some examples. [ABSTRACT FROM AUTHOR]

Using a critical events theoretic analytic lens, we argue that the Covid-19 pandemic had the disruptive power to shake the foundation of sports fanship, much as it affected all aspects of contemporary life across the globe. We conducted a survey of 613 adults in the United States, all of whom self-identified as sports fans. Sports fanship avidity dipped during the height of the pandemic when games, matches, and seasons were cancelled or conducted in protective bubbles without fans in the stands. That dip was temporary. With sports back in full-throttle mode, fanship avidity returned to pre-pandemic levels. Those who identified as strong fans appeared to cherish its return, some even more avid than before. The impact of the pandemic on sports fanship was most acute among those who were not ardent sports fans to begin with—and its impact appears to have extended over time. [ABSTRACT FROM AUTHOR]

In recent years, cryptocurrency has increased in popularity in Indonesia. In Indonesia, based on data from the Ministry of Trade (Kemendag), until the end of May 2021, the number of investors in cryptocurrency assets or crypto money was 6.5 million people. This number has increased by more than 50 percent when compared to 2020 when there were 4 million people. The Pintu application is the first crypto mobile application in Indonesia that is committed to solving crypto investment problems, especially for beginners and ordinary people. Even though it provides benefits, investing in cryptocurrency can provide high profits. In an instant, it can also make a profit. The motion, which is like a roller coaster, requires strong mental readiness to invest in cryptocurrencies. This should also be a critical consideration for investors, especially young investors. Therefore, it is necessary to understand what factors contribute to building stronger attitudes and behavioral intentions toward the PINTU application. This research analyzes the data using the use of technology 2 method with the partial least square (PLS) analysis technique method, which will later be processed in the form of data results in the form of responses of the user when using the application. Facilitating conditions and social influence are the most influential indicators. The results of the study show that behavioral intention to adopt has a relationship with behavioral intention to recommend, and behavioral intention to adopt positively and significantly influences the intention to recommend. [ABSTRACT FROM AUTHOR]

The emergence of vibrations during a roller coaster ride is a recurring phenomenon that can deteriorate the overall experience and accelerate material fatigue. Nevertheless, the causes of such vibrations are still not completely understood and are consequently not fully predictable during the design process. One possible source lies on the irregularities of the rails, acting as a forced external excitation. However, a spectral analysis shows deviations with respect to real measurements [1], as the frequencies are not synchronous with the car velocity divided by the spatial irregularity period. Therefore, there is an indication that the vibrations may be due to self‐excitation and/or that the developed models should consider other phenomena not yet contemplated. This investigation analyses –for the first time to the knowledge of the authors– the plausibility of various causes of self‐excited vibrations during a roller coaster car motion. Given the complex structure of a real roller coaster train and the intricate geometry of the track, the study considers as a first step minimal dynamical models running along a straight track. The cause analyzed in this paper is the contribution of the transversal friction force component that develops in the wheel‐rail contact interface to the destabilization of the longitudinal motion, as well as the effect of the various geometrical and inertial parameters. In this first analysis, no external excitation is considered. For a range of parameters, the minimal system presents a Hopf bifurcation. The results are plausible from the general behavior and thus this cause may be retained as a candidate for the real vibrations occurring in roller coasters. However, the applicability of these preliminary results to general roller coaster motions is not yet confirmed, but a superposition with other causalities may render effective. In further investigations, a complete train motion on curved tracks and external perturbations will be studied to determine the share of the different causes. [ABSTRACT FROM AUTHOR]

Flow field characteristics of Falcon separator are studied by CFD simulation based on Euler-Euler model as multiphase flow model and Reynolds stress model as turbulence model, including particle movement state in delamination area and separation area, three phase (Tangential, radial and axial directions) velocity distribution and turbulence field distribution. Simulation results show that particle movement trajectory is a three-dimensional helical structure with circular motion in groove, which can be regarded as "a circular harmonic motion of a roller coaster"; velocity distribution in the delamination area is almost same as other centrifugal separators but it is quite different in the groove; with feeding of recoil water, the turbulence intensity in the separation area is increased obviously, but it has a lower influence on the disturbance at upper layer of convective membrane, which enhanced the separation effect. [ABSTRACT FROM AUTHOR]

Roller Coaster Dream, a Chinese roller coaster enthusiast club, is a good example of an emerging fanbase in a rapidly developing theme park market.

Recognizing the dynamic nature of affect, we consider observed leader affect and its variability as important social signals that jointly impact employees' daily affective reactions and work engagement. Integrating the emotion as social information model and adaptation-level theory, we hypothesized that the impact of daily observed leader affect on employees' affect and subsequent work engagement is moderated by observed leader affect variability. To test the model, an experience sampling method (ESM) involving two surveys per day over 10 days was employed with a sample of 75 employees. Results indicated that observed leader affect variability weakened the positive relationship between observed leader positive affect and employee work engagement via employee positive affect. Also, observed leader negative affect was negatively related to employee work engagement via employee negative affect, but this indirect effect was not moderated by observed leader affect variability. Our results highlight the critical role of observed leader affect variability in understanding leaders' affective influence on employee affect and engagement. [ABSTRACT FROM AUTHOR]

Following the advances in modern head-mounted displays, research exploring the human experience of virtual environments has seen a surge in interest. Researchers have examined how to promote individuals' sense of presence, i.e., their experience of "being" in the VE, as well as to diminish the negative side effects of cybersickness. Studies investigating the relationship between sense of presence and cybersickness have reported heterogeneous results. Authors that found a positive relation have argued that the phenomena have shared cognitive underpinnings. However, recent literature has reported that positive associations can be explained by the confounding factor of immersion. The current study aims to investigate how cybersickness and sense of presence are associated and develop over time. During the experiment, participants were exposed to a virtual roller coaster and presented orally with questions aimed to quantify their perceived sense of presence and cybersickness. The results of the experiment indicate that cybersickness and sense of presence are both modulated by the time spent in the virtual setting. The utilized short measures for sense of presence and cybersickness were found to be reliable alternatives to multi-item questionnaires. [ABSTRACT FROM AUTHOR]

Studying overseas may offer myriad riches of extraordinary experiences, especially due to the opportunities to immerse into a different academic culture. However, for some, the difference may be a hurdle that brings them into a mental roller coaster along with their academic career. In this reflective paper, against the backdrop of my overseas studies experiences, I recount my bumpy journey of battling the so-called impostor syndrome which prevented me from being productive until I found the lights at the end of the tunnel and finally found a way to move on with my journey and earned my degree. Self-appreciation and community support seemed to be the most important influences that may have led me to be free from the syndrome and to finally achieve my main objectives. [ABSTRACT FROM AUTHOR]

Introduction. Acute compartment syndrome (ACS) occurs secondary to increasing pressure within a fascial compartment that exceeds perfusion pressure. This can be caused by spontaneous hematomas, which can be secondary to prolonged anticoagulation therapy. Eliquis® has not been associated with ACS of the thigh in any of the currently published literature. Identifying ACS early is important because it can reduce the risk of permanent structural damage, limb amputations, and mortality rates. Case Report. A 43-year-old male with past medical history of unprovoked Deep Vein Thrombosis (DVT) eight months prior to presentation on Eliquis® presented to the emergency department for significant right thigh pain after riding a roller coaster. There was increased tone/firmness of the anterior compartment and tenderness on palpation of the proximal two-thirds of the anterior thigh. Imaging, clinical findings, and Stryker needle measurements confirmed ACS secondary to hematoma, which required fasciotomy and evacuation of the hematoma. The patient was temporarily switched to aspirin for DVT prophylaxis postoperatively to prevent new hematoma formation. Six weeks later, the patient arrived at the ED with a DVT that was treated with Eliquis®. Eight months later, the same patient presented with acute right thigh pain that started while lying in bed. A diagnosis of recurrent ACS in the right anterior thigh was made, requiring a fasciotomy. Surgery was successful without any complications. Discussion. Eliquis® is associated with an increased risk of hematoma formation, which can lead to ACS. This is a rare adverse effect that providers should be aware of because it requires early management to prevent ACS-associated complications. This is significant because no currently published literature has identified an association of Eliquis® with ACS in the thigh. In cases of atraumatic ACS, we were unable to find any protocols advocating for or against the use of DVT prophylaxis postfasciotomy in the literature. [ABSTRACT FROM AUTHOR]

Examining the motion of the roller coaster qualitatively, we see that there is a period of deceleration that starts when the leading car enters the loop. The deceleration continues until the entire loop is traversed. The coaster then continues at constant speed until the tail of the train enters the loop. There is a period of acceleration that ends when the tail of the train leaves the loop. The coaster then continues at constant speed, v, equal to the speed before the loop was encountered. [Extracted from the article]

We examined the effects of using mobile devices with immersive virtual reality for a short period on the physiological parameters of both eyes. The average age of the 50 participants (23 men and 27 women) was 17.72 ± 1.48 years, and refractive error ranged from 0 D to − 5.00 D. All the participants wore + 3.00 D glasses and underwent a 5-min relaxation adjustment through the atomization method. The participants wore immersive virtual reality (VR) glasses to watch a movie on a roller coaster for 10 min. Their relevant physiological parameters of the eyes were measured both before and after using VR glasses. Compared with before VR use, no significant difference (P > 0.05) was observed in the near-horizontal vergence and refractive error but a significant difference (P < 0.05) was observed in the amplitude of accommodation, intraocular pressure, divergence/convergence, and stereopsis after VR use. The corneal elastic coefficient was > 0.2 MPa, and we used Friedenwald's eye rigidity relationship to obtain the K value (0.065–0.09). Approximately 10% of the participants experienced cybersickness symptoms such as nausea and dizziness. The use of VR to watch three-dimensional movies reduced intraocular pressure, which may help prevent or treat glaucoma. Moreover, the binocular convergence was higher when viewing near-field objects in VR than in the real world. Therefore, individuals with convergence excess may experience symptoms. Binocular parallax is the most likely cause of cybersickness symptoms. Thus, mobile VR devices with higher quality and comfort are necessary. [ABSTRACT FROM AUTHOR]

Emotions are crucial ingredients of meaningful and memorable tourism experiences. Research methods borrowed from experimental psychology are prime candidates for quantifying emotions while experiences are unfolding. The present article empirically evaluates the methodological feasibility and usefulness of ambulatory recordings of skin conductance responses (SCRs) during a tourism experience. We recorded SCRs in participants while they experienced a roller-coaster ride with or without a virtual reality (VR) headset. Ride elements were identified that related to physical aspects (such as accelerations and braking), to events in the VR environment, and to the physical theming of the roller coaster. VR rides were evaluated more positively than normal rides. SCR time series were meaningfully related to the different ride elements. SCR signals did not significantly predict overall evaluations of the ride. We conclude that psychophysiological measurements are a new avenue for understanding how hospitality, tourism and leisure experiences dynamically develop over time. [ABSTRACT FROM AUTHOR]

We have all experienced the “coronavirus roller coaster” feeling in the previous months. The same metaphor could be applied to work from home, which took adrenaline or melatonin forms depending on the day and activity. For many of us, this was the first experience of working from home, since Serbian legislation does not recognize this form of work engagement. The first analyzes of work from home i our country have shown that such work has both advantages and disadvantages, just like the one in the workplace. However, some of the librarians had the opportunity to learn from those already experienced in working from home, through international projects and activities. Engagement in Europeana and other international initiatives, as well as in several international projects, have made the difficult period of quarantine and pandemic an opportunity for learning and adaptation. And a special advantage was the participation in a series of online workshops Digital Transformation in the time of COVID-19, organized by Europeana for a limited number of participants [ABSTRACT FROM AUTHOR]

The United Nations completed 75 years of its existence in 2020. The last 75 years have been a roller coaster ride for this global institution mandated to maintain peace. However, the UN has received widespread criticism for not reforming its various institutions, particularly the United Nations Security Council (UNSC). The G-4 nations which includes India, have led the call for accelerating the long-awaited reform process. This article analyses the history of the UNSC reform process with a particular focus on India's attempts to become a permanent member to achieve its global ambitions, as well as the major hurdles along the way. [ABSTRACT FROM AUTHOR]

This autoethnographic essay captures fifteen-years of struggles and ephemeral victories associated with developing and sustaining a critical educational leadership doctoral program within a conservative college of education located in the Midwestern United States. Despite having to grapple with non-critical faculty members and neoliberal forces designed to increase enrollment and gut the transformative focus of our program, we were able to keep the program vibrant for over 12 years. To our surprise, the dismantling of the doctoral program began to unfold when one of the core members of the program, a self-professed radical scholar, became a neoliberal administrator obedient to the interests of a new administrative team. The essay provides critical fodder for thinking about the limits and possibilities of sustaining critical educational initiatives amid a sociopolitical context designed to commercialize knowledge, to depoliticize radical intellectuals, and to divide faculty in the struggle to build an egalitarian society. [ABSTRACT FROM AUTHOR]

Stroke rehabilitation suffers from low levels of patient engagement, impeding recovery. Virtual rehabilitation (VR) approaches can improve patient outcomes; however, there is limited understanding of the participant's user experience and the field lacks a validated, objective measure of VR engagement. A neurophysiological measure of engagement in healthy adults was therefore examined, to inform future clinical studies. Twenty-four participants (Mage 26.7 years, range 18–47) interacted with a tabletop VR system (Elements DNA, or EDNA), after which they rated their experience on the presence questionnaire (PQ). Separately, participants completed tasks eliciting low (resting eyes-open and -closed) and high (EDNA VR and roller coaster simulation) levels of engagement while continuous electroencephalogram (EEG) was recorded from a single, left pre-frontal electrode. EEG differences between the resting and simulation conditions included an increase in theta power (p < 0.01) and a decrease in alpha power (p < 0.01). Importantly, theta power in simulation conditions correlated with PQ scores expressing the hands-on EDNA VR experience (rs = 0.38–0.48). In conclusion, the current results provide proof of concept that increased frontal theta power in healthy adults provides a valid measure of user engagement in VR simulation and participation. As the practical potential of VR is increasingly realised in stroke rehabilitation, objective EEG-based measures of engagement may provide a convenient and sensitive technique to assist in evaluating these interventions. [ABSTRACT FROM AUTHOR]