bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perspectives of Students With Disabilities Toward Physical Education: A Review Update 2014–2019
Authors: Holland Katherine , Haegele Justin A. 
Published: January 2021

The purpose of this article is to review qualitative inquiries examining the perspectives of students with disabilities toward physical education (PE) published from 2014 to 2019, as an update to the 2015 review by Haegele and Sutherland. Keyword searches were used to identify articles from nine electronic databases, and seven articles met all inclusion criteria. The seven selected articles were subjected to a narrative analysis, and three thematic clusters emerged: (a) an “inconvenience”: the PE teacher’s influence on quality of experience, (b) “we play together and I like it”: friendships central to the quality of PE experience, and (c) “no lift access to the gym”: barriers to successful participation. Findings from this review support the notion that students with disabilities may have positive experiences in PE if they are offered appropriate modifications and accommodations and are provided with increased kind and supportive interactions with staff and peers.
Macular buckling versus vitrectomy on macular hole associated macular detachment in eyes with high myopia: a randomised trial
Authors: Zhao Xiujuan , Li Yonghao , Ma Wei , Lian Ping , Yu Xiling , Chen Shida , Huang Xia , Liu Bingqian , Lu Lin 
Published: January 2021

AimTo compare the efficacy of macular buckling (MB) and pars plana vitrectomy (PPV) for full-thickness macular holes (FTMH) and associated macular detachment (MD) in highly myopic eyes.MethodsProspective interventional case series of eyes undergoing PPV or MB for FTMH and MD.Main outcome measuresBest-corrected visual acuity (BCVA) at postoperative month 24. Other measured outcomes include the initial surgical success rate, macular hole closure rate and the progression of myopic maculopathy.ResultsA total of 53 eyes from 53 participants were included in this study (26 participants receiving MB and 27 participants receiving PPV), and finally 49 eyes from 49 participants (25 participants in the MB group and 24 participants in the PPV group) were analysed. At postoperative month 24, the BCVA had improved significantly in those that underwent either MB (p<0.001) or PPV (p=0.04). The difference between the groups was not significant (p=0.653). The surgical failure rate after the primary treatment was significantly higher in the PPV group than the MB group (25.00% vs 4.00%, respectively; p=0.04). The macular closure rate was higher in the MB group compared with the PPV group, but the difference was not statistically significant (64.00% vs 58.33%, respectively; p=0.45). Myopic maculopathy development may be more severe following PPV than following MB surgery.ConclusionPatients with high myopia obtained anatomical and functional improvements from either MB or PPV. However, MB achieved a significantly higher success rate in retinal reattachment compared with PPV.Trial registration numberNCT03433547.
Injury prevention knowledge, beliefs and strategies in elite female footballers at the FIFA Women’s World Cup France 2019
Authors: Geertsema Celeste , Geertsema Liesel , Farooq Abdulaziz , Harøy Joar , Oester Chelsea , Weber Alexis , Bahr Roald 
Published: January 2021

ObjectivesThis study assessed knowledge, beliefs and practices of elite female footballers regarding injury prevention.MethodsA survey was sent to players participating in the FIFA Women’s World Cup France 2019. Questions covered three injury prevention domains: (1) knowledge; (2) attitudes and beliefs; (3) prevention practices in domestic clubs. Additionally, ACL injury history was assessed.ResultsOut of 552 players, 196 women responded (35.5%). More than 80% of these considered injury risk to be moderate or high. Players listed knee, ankle, thigh, head and groin as the most important injuries in women’s football. The most important risk factors identified were low muscle strength, followed by poor pitch quality, playing on artificial turf, too much training, reduced recovery and hard tackles. In these elite players, 15% did not have any permanent medical staff in their domestic clubs, yet more than 75% had received injury prevention advice and more than 80% performed injury prevention exercises in their clubs. Players identified the two most important implementation barriers as player motivation and coach attitude. Two-thirds of players used the FIFA 11+ programme in their clubs.ConclusionsThis diverse group of elite players demonstrated good knowledge of risk level and injury types in women’s football. Of the risk factors emphasised by players, there was only one intrinsic risk factor (strength), but several factors out of their control (pitch quality and type, training volume and hard tackles). Still players had positive attitudes and beliefs regarding injury prevention exercises and indicated a high level of implementation, despite a lack of medical support.
Patient and parent perspectives on transition from paediatric to adult healthcare in rheumatic diseases: an interview study
Authors: Jiang Ivy , Major Gabor , Singh-Grewal Davinder , Teng Claris , Kelly Ayano , Niddrie Fiona , Chaitow Jeffrey , O’Neill Sean , Hassett Geraldine , Damodaran Arvin , Bernays Sarah , Manera Karine , Tong Allison , Tunnicliffe David J 
Published: January 2021

ObjectivesTo describe the experiences, priorities, and needs of patients with rheumatic disease and their parents during transition from paediatric to adult healthcare.SettingFace-to-face and telephone semistructured interviews were conducted from December 2018 to September 2019 recruited from five hospital centres in Australia.ParticipantsFourteen young people and 16 parents were interviewed. Young people were included if they were English speaking, aged 14–25 years, diagnosed with an inflammatory rheumatic disease (eg, juvenile idiopathic arthritis, juvenile dermatomyositis, systemic lupus erythematosus, panniculitis, familial Mediterranean fever) before 18 years of age. Young people were not included if they were diagnosed in the adult setting.ResultsWe identified four themes with respective subthemes: avoid repeat of past disruption (maintain disease stability, preserve adjusted personal goals, protect social inclusion); encounter a daunting adult environment (serious and sombre mood, discredited and isolated identity, fear of a rigid system); establish therapeutic alliances with adult rheumatology providers (relinquish a trusting relationship, seek person-focused care, redefine personal–professional boundaries, reassurance of alternative medical supports, transferred trust to adult doctor) and negotiate patient autonomy (confidence in formerly gained independence, alleviate burden on patients, mediate parental anxiety).ConclusionsDuring transition, patients want to maintain disease stability, develop a relationship with their adult provider centralised on personal goals and access support networks. Strategies to comprehensively communicate information between providers, support self-management, and negotiate individualised goals for independence during transition planning may improve satisfaction, and health and treatment outcomes.
Temporomandibular disorders in patients with early rheumatoid arthritis and at-risk individuals in the Dutch population: a cross-sectional study
Authors: Kroese Johanna M , Volgenant Catherine M C , Crielaard Wim , Loos Bruno , van Schaardenburg Dirkjan , Visscher Corine M , Lobbezoo Frank 
Published: January 2021

ObjectiveTo evaluate the prevalence of temporomandibular disorders (TMD) in patients with early rheumatoid arthritis (ERA) and individuals at-risk of RA.Methods150 participants were recruited in three groups (50 per group): (1) patients with ERA (2010 EULAR criteria) (2) at-risk individuals and (3) healthy controls. All participants were tested for seropositivity of rheumatoid factor and anticitrullinated protein antibodies. A possible TMD diagnosis was determined according to the standardised and validated diagnostic criteria for TMD (DC/TMD) in five categories: myalgia, arthralgia, articular disc displacement, degenerative joint disease and headache attributed to TMD. Results were tested for the prevalence of TMD (all categories combined) and TMD pain (myalgia and/or arthralgia). To investigate a possible role for bruxism, a probable sleep and/or awake bruxism diagnosis was determined based on self-report and several clinical features.ResultsThe prevalence of any TMD diagnosis did not differ between the three groups. However, at-risk individuals more often had a TMD-pain diagnosis than healthy controls (p=0.046). No such difference was found between the ERA group and the control group. However, within the ERA group, seronegative patients had a TMD-pain diagnosis more often than seropositive patients (4/12 (33%) vs 3/38 (8%), p=0.048). Participants with a TMD-pain diagnosis were more often diagnosed with probable sleep bruxism than those without a TMD-pain diagnosis.ConclusionThe prevalence of TMD pain is increased in individuals at-risk of RA and seronegative ERA patients, and is associated with bruxism signs and symptoms. These results suggest that health professionals should be alert to TMD pain in these groups.
HIV non-occupational postexposure prophylaxis (nPEP) usage among five key populations in China
Authors: Li Haochu , Wei Ran , Piqueiras Eduardo , Chow Eric P F , Jiao Kedi , Lewis Taylor , Ma Wei 
Published: January 2021

ObjectivesTo examine the feasibility of non-occupational postexposure prophylaxis (nPEP) as a national strategy for HIV prevention in China, we investigated nPEP usage and related sociodemographic and behavioural factors among five key populations at high risk of contracting HIV.MethodsWe conducted a cross-sectional study among five key populations from November 2018 to September 2019 in China using convenience sampling to recruit participants aged ≥18 years, self-reporting HIV status as either negative or unknown and providing written informed consent. Univariable and multivariable logistic regression models were fitted.ResultsOur analysis included data from 2022 participants with a mean age of 35 years (SD=11.62). Only 57 (2.82%) participants had ever used nPEP. Sociodemographic and behavioural factors related to nPEP usage included populations (p<0.0001), age (p<0.05), education (p<0.05), nPEP knowledge (p<0.01), receiving conventional HIV prevention services (p<0.05) and HIV testing (p<0.05). A significant percentage (26%) of nPEP users used nPEP medication more than once. Challenges and concerns, such as multiple use of nPEP and syndemic conditions, were emerging.ConclusionsKey populations in China had low nPEP usage rates. Female sex workers, people who use drugs, older and illiterate individuals with poor nPEP knowledge, not using HIV prevention services or never tested for HIV should be emphasised. Implementing nPEP services would be an important way to access high-risk individuals for intensive and tailored HIV prevention and intervention. Challenges of providing nPEP services and future study foci are highlighted.
Highly Concurrent Latency-tolerant Register Files for GPUs
Authors: Sadrosadati Mohammad , Mirhosseini Amirhossein , Hajiabadi Ali , Ehsani Seyed Borna , Falahati Hajar , Sarbazi-Azad Hamid , Drumond Mario , Falsafi Babak , Ausavarungnirun Rachata , Mutlu Onur 
Published: January 2021

Graphics Processing Units (GPUs) employ large register files to accommodate all active threads and accelerate context switching. Unfortunately, register files are a scalability bottleneck for future GPUs due to long access latency, high power consumption, and large silicon area provisioning. Prior work proposes hierarchical register file to reduce the register file power consumption by caching registers in a smaller register file cache. Unfortunately, this approach does not improve register access latency due to the low hit rate in the register file cache.
In this article, we propose the Latency-Tolerant Register File (LTRF) architecture to achieve low latency in a two-level hierarchical structure while keeping power consumption low. We observe that compile-time interval analysis enables us to divide GPU program execution into intervals with an accurate estimate of a warp’s aggregate register working-set within each interval. The key idea of LTRF is to prefetch the estimated register working-set from the main register file to the register file cache under software control, at the beginning of each interval, and overlap the prefetch latency with the execution of other warps. We observe that register bank conflicts while prefetching the registers could greatly reduce the effectiveness of LTRF. Therefore, we devise a compile-time register renumbering technique to reduce the likelihood of register bank conflicts. Our experimental results show that LTRF enables high-capacity yet long-latency main GPU register files, paving the way for various optimizations. As an example optimization, we implement the main register file with emerging high-density high-latency memory technologies, enabling 8× larger capacity and improving overall GPU performance by 34%.
Reducing Energy in GPGPUs through Approximate Trivial Bypassing
Authors: Atoofian Ehsan , Shaikh Zayan , Jannesari Ali 
Published: January 2021

General-purpose computing using graphics processing units (GPGPUs) is an attractive option for acceleration of applications with massively data-parallel tasks. While performance of modern GPGPUs is increasing rapidly, the power consumption of these devices is becoming a major concern. In particular, execution units and register file are among the top three most power-hungry components in GPGPUs. In this work, we exploit trivial instructions to reduce power consumption in GPGPUs.
Trivial instructions are those instructions that do not need computations, i.e., multiplication by one. We found that, during the course of a program's execution, a GPGPU executes many trivial instructions. Execution of these instructions wastes power unnecessarily. In this work, we propose trivial bypassing which skips execution of trivial instructions and avoids unnecessary allocation of resources for trivial instructions. By power gating execution units and skipping trivial computing, trivial bypassing reduces both static and dynamic power. Also, trivial bypassing reduces dynamic energy of register file by avoiding access to register file for source and/or destination operands of trivial instructions. While trivial bypassing reduces energy of GPGPUs, it has detrimental impact on performance as a power-gated execution unit requires several cycles to resume its normal operation. Conventional warp schedulers are oblivious to the status of execution units. We propose a new warp scheduler that prioritizes warps based on availability of execution units. We also propose a set of new power management techniques to reduce performance penalty of power gating, further. To increase energy saving of trivial bypassing, we also propose approximating operands of instructions. We offer a set of new techniques to approximate both integer and floating-point instructions and increase the pool of trivial instructions. Our evaluations using a diverse set of benchmarks reveal that our proposed techniques are able to reduce energy of execution units by 11.2% and dynamic energy of register file by 12.2% with minimal performance and quality degradation.
Internalizing representation independence with univalence
Authors: Angiuli Carlo , Cavallo Evan , Mörtberg Anders , Zeuner Max 
Published: January 2021

In their usual form, representation independence metatheorems provide an external guarantee that two implementations of an abstract interface are interchangeable when they are related by an operation-preserving correspondence. If our programming language is dependently-typed, however, we would like to appeal to such invariance results within the language itself, in order to obtain correctness theorems for complex implementations by transferring them from simpler, related implementations. Recent work in proof assistants has shown that Voevodsky's univalence principle allows transferring theorems between isomorphic types, but many instances of representation independence in programming involve non-isomorphic representations.
In this paper, we develop techniques for establishing internal relational representation independence results in dependent type theory, by using higher inductive types to simultaneously quotient two related implementation types by a heterogeneous correspondence between them. The correspondence becomes an isomorphism between the quotiented types, thereby allowing us to obtain an equality of implementations by univalence. We illustrate our techniques by considering applications to matrices, queues, and finite multisets. Our results are all formalized in Cubical Agda, a recent extension of Agda which supports univalence and higher inductive types in a computationally well-behaved way.
Simplifying dependent reductions in the polyhedral model
Authors: Yang Cambridge , Atkinson Eric , Carbin Michael 
Published: January 2021

A Reduction – an accumulation over a set of values, using an associative and commutative operator – is a common computation in many numerical computations, including scientific computations, machine learning, computer vision, and financial analytics. Contemporary polyhedral-based compilation techniques make it possible to optimize reductions, such as prefix sums, in which each component of the reduction’s output potentially shares computation with another component in the reduction. Therefore an optimizing compiler can identify the computation shared between multiple components and generate code that computes the shared computation only once.
These techniques, however, do not support reductions that – when phrased in the language of the polyhedral model – span multiple dependent statements. In such cases, existing approaches can generate incorrect code that violates the data dependences of the original, unoptimized program.
In this work, we identify and formalize the optimization of dependent reductions as an integer bilinear program. We present a heuristic optimization algorithm that uses an affine sequential schedule of the program to determine how to simplfy reductions yet still preserve the program’s dependences.

We demonstrate that the algorithm provides optimal complexity for a set of benchmark programs from the literature on probabilistic inference algorithms, whose performance critically relies on simplifying these reductions. The complexities for 10 of the 11 programs improve siginifcantly by factors at least of the sizes of the input data, which are in the range of 10
4
to 10
6
for typical real application inputs. We also confirm the significance of the improvement by showing speedups in wall-clock time that range from 1.1x to over 10
6
x.
An abstract interpretation for SPMD divergence on reducible control flow graphs
Authors: Rosemann Julian , Moll Simon , Hack Sebastian 
Published: January 2021

Vectorizing compilers employ divergence analysis to detect at which program point a specific variable is uniform, i.e. has the same value on all SPMD threads that execute this program point. They exploit uniformity to retain branching to counter branch divergence and defer computations to scalar processor units. Divergence is a hyper-property and is closely related to non-interference and binding time. There exist several divergence, binding time, and non-interference analyses already but they either sacrifice precision or make significant restrictions to the syntactical structure of the program in order to achieve soundness.
In this paper, we present the first abstract interpretation for uniformity that is general enough to be applicable to reducible CFGs and, at the same time, more precise than other analyses that achieve at least the same generality.
Our analysis comes with a correctness proof that is to a large part mechanized in Coq. Our experimental evaluation shows that the compile time and the precision of our analysis is on par with LLVM's default divergence analysis that is only sound on more restricted CFGs. At the same time, our analysis is faster and achieves better precision than a state-of-the-art non-interference analysis that is sound and at least as general as our analysis.
Context-bounded verification of liveness properties for multithreaded shared-memory programs
Authors: Baumann Pascal , Majumdar Rupak , Thinniyam Ramanathan S. , Zetzsche Georg 
Published: January 2021

We study context-bounded verification of liveness properties of multi-threaded, shared-memory programs, where each thread can spawn additional threads. Our main result shows that context-bounded fair termination is decidable for the model; context-bounded implies that each spawned thread can be context switched a fixed constant number of times. Our proof is technical, since fair termination requires reasoning about the composition of unboundedly many threads each with unboundedly large stacks. In fact, techniques for related problems, which depend crucially on replacing the pushdown threads with finite-state threads, are not applicable. Instead, we introduce an extension of vector addition systems with states (VASS), called VASS with balloons (VASSB), as an intermediate model; it is an infinite-state model of independent interest. A VASSB allows tokens that are themselves markings (balloons). We show that context bounded fair termination reduces to fair termination for VASSB. We show the latter problem is decidable by showing a series of reductions: from fair termination to configuration reachability for VASSB and thence to the reachability problem for VASS. For a lower bound, fair termination is known to be non-elementary already in the special case where threads run to completion (no context switches).
We also show that the simpler problem of context-bounded termination is 2EXPSPACE-complete, matching the complexity bound---and indeed the techniques---for safety verification. Additionally, we show the related problem of fair starvation, which checks if some thread can be starved along a fair run, is also decidable in the context-bounded case. The decidability employs an intricate reduction from fair starvation to fair termination. Like fair termination, this problem is also non-elementary.
A practical mode system for recursive definitions
Authors: Reynaud Alban , Scherer Gabriel , Yallop Jeremy 
Published: January 2021

In call-by-value languages, some mutually-recursive definitions can be safely evaluated to build recursive functions or cyclic data structures, but some definitions (let rec x = x + 1) contain vicious circles and their evaluation fails at runtime. We propose a new static analysis to check the absence of such runtime failures.
We present a set of declarative inference rules, prove its soundness with respect to the reference source-level semantics of Nordlander, Carlsson, and Gill [2008], and show that it can be directed into an algorithmic backwards analysis check in a surprisingly simple way.
Our implementation of this new check replaced the existing check used by the OCaml programming language, a fragile syntactic criterion which let several subtle bugs slip through as the language kept evolving. We document some issues that arise when advanced features of a real-world functional language (exceptions in first-class modules, GADTs, etc.) interact with safety checking for recursive definitions.