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Theory, Experience, and Instinct: How AAA Game Studio UX Leaders Navigate Pre-Production
(Association for Computing Machinery, 2026-04-13) Randelshofer, Ivana; Tu, Joseph; Cao, Yifan; Mogavi, Reza Hadi; Mäkelä, Ville; Nacke, Lennart E.
Academic frameworks have limited practical application in game pre-production because they do not map well to industry contexts and constraints. Through semi-structured interviews with 15 senior UX leaders from AAA game studios, we examined how practitioners make design decisions during early development. Our findings show a tripartite approach: (1) academically-grounded translation, where practitioners selectively adapt formal theories; (2) experience-based codification, where teams systematize tacit knowledge into reusable artifacts; and (3) intuitive gut feeling, where expertise guides decisions without formal frameworks. We introduce organizational structures (i.e., strike teams and competency teams) that shape how academic knowledge is translated in practice. Our work challenges the traditional view that practitioners should directly apply academic theory. Academia’s unique opportunity here is to provide the conceptual building blocks that enable solutions practitioners need. A change that begins with knowing how practitioners already translate academic knowledge into actionable practice.
User traits mosaic: Understanding the multifaceted landscape of social VR users
(Elsevier, 2026-03-04) Kukshinov, Eugene; Harley, Daniel; Tu, Joseph; Wang, Derrick M.; Hadan, Hilda; Nacke, Lennart E.
Social Virtual Reality (SVR) consists of multi-user digital platforms that afford various co-located activities and collaborations in simulated environments. Despite considerable knowledge about separate ways SVR users engage these platforms, we currently lack a comprehensive categorization of user practices in SVR that also demonstrates connections between these practices. To address this gap, we build upon existing research and report a survey-based, open-ended investigation, analyzing structured qualitative data that reveals how people use SVR, confirming prior research, but also gaining new evidence. We identified 23 distinct SVR user traits based on their activities, motivations, and attitudes towards avatars and social orientations. Our categorization not only clarifies SVR user behaviors and describes the overall current social landscape of SVR, but it also offers valuable insights for design frameworks to enhance the experiential and collaborative potential of SVR. We conclude by providing suggestions for how our categorizations might be used to describe the social connections and relationships between users, address trait-specific challenges, and better cater to users’ needs, whether they seek social connection, solo exploration, or specific practices within SVR.
Z-score differences based on cross-sectional growth charts do not reflect the growth rate of very low birth weight infants
(Public Library of Science, 2019-05-07) Rochow, Niels; Landau-Crangle, Erin; So, Hon Yiu; Pelc, Anna; Fusch, Gerhard; Dabritz, Jan; Gopel, Wolfgang; Fusch, Christoph
Objective To test whether the assessment of growth in very low birth weight infants during the hospital stay using z-score differences (Zdiff) is confounded by gestational age (GA), birth weight percentile (BW%ile), and length of the observation period (LOP). We hypothesize that Zdiff calculated from growth charts based on birth weight data introduces a systematic statistical error leading to falsely classified growth as restricted in infants growing similarly to the 50th percentile. Methods The observational study included 6,926 VLBW infants from the German Neonatal Network (2009 to 2015). Inclusion criterion was discharge between 37 and 41 weeks postmenstrual age. For each infant, Zdiff, weight gain velocity, and reference growth rate (50th percentile Fenton) from birth to discharge were calculated. To account for gestational age dependent growth rates, assessment of growth was standardized calculating the weight gain ratio (WGR) = weight gain velocity/reference growth rate. The primary outcome is the variation of the Zdiff-to-WGR relationship. Results Zdiff and WGR showed a weak agreement with a Zdiff of -0.74 (-1.03, -0.37) at the reference growth rate of the 50th percentile (WGR = 1). A significant proportion (n = 1,585; 23%) of infants with negative Zdiff had weight gain velocity above the 50th percentile's growth rate. Zdiff to WGR relation was significantly affected by the interaction of GA x BW%ile x LOP. Conclusion This study supports the hypothesis that Zdiff, which are calculated using birth weights, are confounded by skewed reference data and can lead to misinterpretation of growth rates. New concepts like individualized growth trajectories may have the potential to overcome this limitation.
CancerInSilico: An R/Bioconductor package for combining mathematical and statistical modeling to simulate time course bulk and single cell gene expression data in cancer
(Public Library of Science, 2019-04-19) Sherman, Thomas D.; Kagohara, Luciane T.; Cao, Raymon; Cheng, Raymond; Satriano, Matthew; Considine, Michael; Krigsfeld, Gabriel; Ranaweera, Ruchira; Tang, Yong; Jablonski, Sandra A.; Stein-O'Brien, Genevieve; Gaykalova, Daria A.; Weiner, Louis M.; Chung, Christine H.; Fertig, Elana J.
Bioinformatics techniques to analyze time course bulk and single cell omics data are advancing. The absence of a known ground truth of the dynamics of molecular changes challenges benchmarking their performance on real data. Realistic simulated time-course datasets are essential to assess the performance of time course bioinformatics algorithms. We develop an R/Bioconductor package, CancerInSilico, to simulate bulk and single cell transcriptional data from a known ground truth obtained from mathematical models of cellular systems. This package contains a general R infrastructure for running cell-based models and simulating gene expression data based on the model states. We show how to use this package to simulate a gene expression data set and consequently benchmark analysis methods on this data set with a known ground truth. The package is freely available via Bioconductor: http://bioconductor.org/packages/CancerInSilico/
Using EMRALD to assess baseline body mass index among children living within and outside communities participating in the Ontario, Canada Healthy Kids Community Challenge
(Public Library of Science, 2019-04-11) Orr, Sarah K.; Tu, Karen; Carsley, Sarah; Chung, Hannah; Holder, Laura; Jabbari, Shirin; Harrington, Daniel W.; Manson, Heather
Objectives The Healthy Kids Community Challenge is a large-scale, centrally-coordinated, community-based intervention in Ontario, Canada that promotes healthy behaviours towards improving healthy weights among children. With the goal of exploring tools available to evaluators, we leveraged electronic medical records from primary care physicians to assess child weights prior to launch of the Healthy Kids Community Challenge. This study compares the baseline (i.e. pre-intervention) prevalence of overweight and obesity in children 1-12 years of age living within and outside Healthy Kids Community Challenge communities. Design Cross-sectional analysis of a primary care patient cohort. Setting Electronic Medical Record Administrative data Linked Database (EMRALD) in Ontario, Canada. Participants A cohort of 19 920 Ontario children who are rostered to an EMRALD physician. Children were 1-12 years of age as a primary care visit with recorded measured height and weight, between January 1, 2014 and December 31, 2015. Outcome measure Overweight and obesity as determined by age- and sex-standardized body mass index using World Health Organization's Growth Standards. Results In Healthy Kids Community Challenge communities, 25.6% (95% Cl 24.6-26.6%) of children had zBMI above normal (i.e. >1) compared to 26.7% (95% Cl 25.9-27.5%) for children living outside of Healthy Kids Community Challenge communities. Conclusions Despite some differences in sociodemographic characteristics, zBMI of children aged 1-12 years were similar inside and outside of Healthy Kids Community Challenge community boundaries prior to program launch.
Concordance in wetland physicochemical conditions, vegetation, and surroundign land cover is robust to data extraction approach
(Public Library of Science, 2019-05-31) Kraft, Adam J.; Robinson, Derek T.; Evans, Ian S.; Rooney, Rebecca C.
Concordance among wetland physicochemical conditions, vegetation, and surrounding land cover may result from the influence of land cover on the sources of plant propagules, on physicochemical conditions, and their subsequent determination of growing conditions. Alternatively, concordance may result if differences in climate, soils, and species pools are spatially confounded with differences in human population density and land conversion. Further, we expect that land cover within catchment boundaries will be more predictive than land cover in symmetrical buffers if runoff is a major pathway. We measured concordance between land cover, wetland vegetation and physicochemical conditions in 48 prairie pothole wetlands, controlling for inter-wetland distance. We contrasted land-cover data collected over a four-year period by multiple extraction approaches including topographically-delineated catchments and nested 30 m to 5,000 m radius buffers. After factoring out inter-wetland distance, physiochemical conditions were significantly concordant with land cover. Vegetation was not significantly concordant with land cover, though it was strongly and significantly concordant with physicochemical conditions. More, concordance was as strong when land cover was extracted from buffers <500 m in radius as from catchments, indicating the mechanism responsible is not topographically constrained. We conclude that local landscape structure does not directly influence wetland vegetation composition, but rather that vegetation depends on 1) physicochemical conditions in the wetland that are affected by surrounding land cover and on 2) regional factors such as the vegetation species pool and geographic gradients in climate, soil type, and land use.
Exploring correlations between neuropsychological measures and domain-specific consistencty in associations with n-3 LCPUFA status in 8-9 year-old boys and girls
(Public Library of Science, 2019-05-22) Teisen, Marie N.; Niclasen, Janni; Vuholm, Stine; Lundbye-Jensen, Jesper; Stark, Ken D.; Damsgaard, Camilla T.; Geertsen, Svend S.; Lauritzen, Lotte
Long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFA) have in some studies been associated with cognitive and socioemotional outcomes in children, but results are inconsistent possibly due to the use of different tests and potential gender-specific effects. The objective of this cross-sectional study was to explore overall patterns in neuropsychological scores as well as correlations between scores within specific domains, and to examine potential gender differences and consistency in associations with n-3 LCPUFA status. In 199 Danish 8–9 year-old children, we performed a large battery of tests and questionnaires on attention, processing speed, executive functions, memory, and socioemotional traits, and measured erythrocyte fatty acid composition. Principal component analyses (PCA) showed that most of the variation in both cognitive performance and socioemotional traits was explained by overall performance, followed by speed-accuracy trade off and externalizing vs. internalizing problems, respectively. Boys had higher speed, lower attention and higher externalizing problem scores than girls. Measures of performance within both processing speed and attention domains correlated moderately, whereas no correlations were found for measures of executive functions apart from some weak correlations for impulsivity. Parent-rated scores for both externalizing and internalizing problems correlated strongly, whereas correlations with child-rated scores were weak. Scores within specific domains did not consistently associate with n-3 LCPUFA, except for processing speed measures which all pointed to faster processing with increased n-3 LCPUFA status. Gender differences in the associations were observed for attention and impulsivity. Child- but not parent-rated internalizing and social problems tended to associate directly with n-3 LCPUFA, supported by increased internalizing problems measured by the PCA component. In conclusion, measures of speed and attention seem to represent these domains in general, whereas single measures of more complex cognitive functions should be interpreted with caution. One approach could be to use multiple tests and create multivariate scores to guide interpretations. Furthermore, the results indicate a need to consider both parent- and child-rated socioemotional scores and gender differences in neuropsychological functions e.g. in investigations of n-3 LCPUFA effects.
Severe wildfire affects the thermal and moisture regimes of at-risk turtle nesting habitat
(BioOne, 2024-06) Markle, Chantel; Simone, Kyra; Wilkinson, Sophie; Freeman, Hope; Wiebe, Sarah; Sherwood, Emma; Waddington, James
Natural wildfire regimes are important for ecosystem succession, but increased frequency and severity of wildfire due to climate change can negatively alter habitat characteristics. In 2018, over 11,000 ha of a granite rock barrens landscape that extends along the eastern shoreline of Georgian Bay, Lake Huron, burned in a wildfire. This landscape is a biodiversity hotspot providing habitat for many species at risk, including Emydoidea blandingii (Blanding's Turtle) and Clemmys guttata (Spotted Turtle), where turtles nest in shallow soil deposits in cracks and crevices in the bedrock. The burned, open rock-barren habitat had ∼70% fewer available nesting sites, but suitability of remaining nest habitat was unknown. To assess the impact of the wildfire on the suitability of turtle nesting habitat, we compared soil properties and in situ thermal and moisture regimes at turtle-selected nest sites, burned and unburned rock barren habitat, and burned forested uplands that may provide newly available habitat as a result of increased canopy openness following fire. Burned and unburned rock barren habitats drained quickly following rainfall, similar to turtle-selected sites, whereas burned forested uplands drained more slowly and provided wetter incubation conditions. Burned forested uplands provided a comparable thermal regime to turtle-selected nest sites and were often moss-dominated, with a relatively open canopy. Hatch success was estimated to be 20% lower at burned rock-barren habitats compared to unburned sites. Our findings suggest that severe wildfire affects soil thermal and moisture regimes, which can negatively alter the suitability of nest habitat, but burned upland forests are likely to provide suitable nesting habitat for at-risk turtles in the first years following fire.
Designer Sinorhizobium meliloti strains and multi-functional vectors enable direct inter-kingdom DNA transfer
(Public Library of Science, 2019-06-17) Brumwell, Stephanie L.; MacLeod, Michael R.; Huang, Tony; Cochrane, Ryan R.; Meaney, Rebecca S.; Zamani, Maryam; Matysiakiewicz, Ola; Dan, Kaitlyn N.; Janakirama, Preetam; Edgell, David R.; Charles, Trevor C.; Finan, Turlough M.; Karas, Bogumil J.
Storage, manipulation and delivery of DNA fragments is crucial for synthetic biology applications, subsequently allowing organisms of interest to be engineered with genes or pathways to produce desirable phenotypes such as disease or drought resistance in plants, or for synthesis of a specific chemical product. However, DNA with high G+C content can be unstable in many host organisms including Saccharomyces cerevisiae. Here, we report the development of Sinorhizobium meliloti, a nitrogen-fixing plant symbioticα-Proteobacterium, as a novel host that can store DNA, and mobilize DNA to E. coli, S. cerevisiae, and the eukaryotic microalgae Phaeodactylum tricornutum. To achieve this, we deleted the hsdR restriction-system in multiple reduced genome strains of S. meliloti that enable DNA transformation with up to 1.4 x 105 and 2.1 x 103 CFU μg-1 of DNA efficiency using electroporation and a newly developed polyethylene glycol transformation method, respectively. Multi-host and multi-functional shuttle vectors (MHS) were constructed and stably propagated in S. meliloti, E. coli, S. cerevisiae, and P. tricornutum. We also developed protocols and demonstrated direct transfer of these MHS vectors via conjugation from S. meliloti to E. coli, S. cerevisiae, and P. tricornutum. The development of S. meliloti as a new host for inter-kingdom DNA transfer will be invaluable for synthetic biology research and applications, including the installation and study of genes and biosynthetic pathways into organisms of interest in industry and agriculture.
Statistical methods for classification of 5hmC levels based on the Illumina Inifinium HumanMethylation450 (450k) array data, under the paired bisulfite (BS) and oxidative bisulfite (oxBS) treatment
(Public Library of Science, 2019-06-13) Slynko, Alla; Benner, Axel
Hydroxymethylcytosine (5hmC) methylation is a well-known epigenetic mark that is involved in gene regulation and may impact genome stability. To investigate a possible role of 5hmC in cancer development and progression, one must be able to detect and quantify its level first. In this paper, we address the issue of 5hmC detection at a single base resolution, starting with consideration of the well-established 5hmC measure Δβ and, in particular, with an analysis of its properties, both analytically and empirically. Then we propose several alternative hydroxymethylation measures and compare their properties with those of Δβ. In the absence of a gold standard, the (pairwise) resemblance of those 5hmC measures to Δβ is characterized by means of a similarity analysis and relative accuracy analysis. All results are illustrated on matched healthy and cancer tissue data sets as derived by means of bisulfite (BS) and oxidative bisulfite converting (oxBS) procedures.
High rates of health care utilization in pediatric multiple sclerosis: A Canadian population-based study
(Public Library of Science, 2019-06-11) Marrie, Ruth Ann; O'Mahony, Julia; Maxwell, Colleen J.; Ling, Vicki; Yeh, E. Ann; Arnold, Douglas L.; Bar-Or, Amit; Banwell, Brenda
We aimed to compare health care utilization of children with pediatric-onset multiple sclerosis to that of age, sex and geographically-matched children without multiple sclerosis. Using population-based administrative data from Ontario, Canada for the period 2003–2014, we applied a validated case definition to identify persons aged ≤18 years with multiple sclerosis. We identified up to 5 children without multiple sclerosis matched on sex, age, and region of residence. In each cohort, we determined annual rates of any hospitalization and physician services use. Using general linear models we compared utilization rates adjusting for age, sex, region, socioeconomic status and year. Subsequently, we limited the analysis to incident cases of multiple sclerosis and their matches, and compared rates of utilization in the year of multiple sclerosis diagnosis, and the three years thereafter. We identified 659 youth with multiple sclerosis (428 incident cases), and 3,294 matched controls. Two-thirds of both cohorts were female. After adjustment for sociodemographic factors and year, the multiple sclerosis cohort was more likely to be hospitalized than the matched cohort (odds ratio 15.2; 95%CI: 12.0, 19.1), and had higher rates of ambulatory physician visits (rate ratio 4.58; 95%CI: 4.26, 4.92). The odds of hospitalization (odds ratio 40.1; 95%CI: 27.1, 59.5) and physician visits (rate ratio 5.14; 95%CI: 4.63, 5.71) were markedly elevated in the year of MS diagnosis, declining thereafter but remaining elevated versus the matched cohort. Children with multiple sclerosis have substantially elevated rates of health care utilization as compared to matched children without multiple sclerosis, over calendar time and throughout the early disease course.
Charting pathways to climate change mitigation in a coupled socio-climate model
(Public Library of Science, 2019-06-06) Bury, Thomas M.; Bauch, Chris T.; Anand, Madhur
Geophysical models of climate change are becoming increasingly sophisticated, yet less effort is devoted to modelling the human systems causing climate change and how the two systems are coupled. Here, we develop a simple socio-climate model by coupling an Earth system model to a social dynamics model. We treat social processes endogenously—emerging from rules governing how individuals learn socially and how social norms develop—as well as being influenced by climate change and mitigation costs. Our goal is to gain qualitative insights into scenarios of potential socio-climate dynamics and to illustrate how such models can generate new research questions. We find that the social learning rate is strongly influential, to the point that variation of its value within empirically plausible ranges changes the peak global temperature anomaly by more than 1°C. Conversely, social norms reinforce majority behaviour and therefore may not provide help when we most need it because they suppress the early spread of mitigative behaviour. Finally, exploring the model’s parameter space for mitigation cost and social learning suggests optimal intervention pathways for climate change mitigation. We find that prioritising an increase in social learning as a first step, followed by a reduction in mitigation costs provides the most efficient route to a reduced peak temperature anomaly. We conclude that socio-climate models should be included in the ensemble of models used to project climate change.
A local optimization framework for addressing conservation conflicts in mosaic ecosystems
(Public Library of Science, 2019-05-31) Nowack, Shane; Bauch, Chris T.; Anand, Madhur
An effective strategy to resolve conservation conflicts on lands outside of nature reserves is to consider the spatial arrangement of agricultural and native vegetation parcels such that the ecological value of the landscape is improved without reducing the amount of land used for agricultural production. Global optimization methods have been used to identify the best spatial arrangement of land parcels for a given project goal, but these methods are not designed to provide pathways to reach the optimum from the initial landscape. Here we describe how local search algorithms can be used to develop land parcel rearrangement pathways to obtain a landscape that sustains greater species richness than the initial landscape without changing the amount of land used for agricultural production. To demonstrate how the local optimization framework can be applied, an ecological setting based on a forest-grassland mosaic ecosystem in Rio Grande do Sul, Brazil was constructed. Plant samples collected from this region were used to construct species area curves. Multiple locally optimal solutions that improved the modeled species richness of the landscape almost to globally optimal levels were identified. To support the results, the algorithm was also applied to a 306,250 ha forest-grassland region of Rio Grande do Sul. The case study results suggested that conservation polices solely based on landowners satisfying a legal reserve percentage on their property should be revised to consider landscape-level connectivity. Providing multiple possible solutions for landscape configurations using local optimization methods may improve managerial flexibility for decision-makers, compared to global optimization approaches providing a single solution. Furthermore, the algorithm details the parcel exchange pathways that are required to reach the optimal land state. We conclude that local and global optimization approaches can be used in combination to improve land use decision-making for conservation, in mosaic ecosystems as well as other terrestrial ecosystems
An acoustic source model for asymmetric intraglottal flow with application to reduced-order models of the vocal folds
(Public Library of Science, 2019-07-25) Erath, Byron D.; Peterson, Sean D.; Weiland, Kelley S.; Plesniak, Michael W.; Zanartu, Matias
The complex three-way interaction between airflow, tissue, and sound, for asymmetric vocal fold vibration, is not well understood. Current modeling efforts are not able to explain clinical observations where drastic differences in sound production are often observed, with no noticeable differences in the vocal fold kinematics. To advance this understanding, an acoustical model for voiced sound generation in the presence of asymmetric intraglottal flows is developed. The source model operates in conjunction with a wave reflection analog propagation scheme and an asymmetric flow description within the glottis. To enable comparison with prior work, the source model is evaluated using a well-studied two-mass vocal fold model. The proposed source model is evaluated through acoustic measures of interest, including radiated sound pressure level, maximum flow declination rate, and spectral tilt, and also via its effects on the vocal fold dynamics. The influence of the model, in comparison to the standard symmetric Bernoulli flow description, results in an increased transfer of energy from the fluid to the vocal folds, increased radiated sound pressure level and maximum flow declination rate, and decreased spectral tilt. These differences are most pronounced for asymmetric vocal fold configurations that mimic unilateral paresis and paralysis, where minor kinematic changes can result in significant acoustic and aerodynamic differences. The results illustrate that fluid effects arising from asymmetric glottal flow can play an important role in the acoustics of pathological voiced speech.
How to build a fruit: Transcriptomics of a novel fruit type in the Brassiceae
(Public Library of Science, 2019-07-18) Carey, Shane; Mendler, Kerrin; Hall, Jocelyn C.
Comparative gene expression studies are invaluable for predicting how existing genetic pathways may be modified or redeployed to produce novel and variable phenotypes. Fruits are ecologically important organs because of their impact on plant fitness and seed dispersal, modifications in which results in morphological variation across species. A novel fruit type in the Brassicaceae known as heteroarthrocarpy enables distinct dispersal methods in a single fruit through segmentation via a lateral joint and variable dehiscence at maturity. Given the close relationship to Arabidopsis, species that exhibit heteroarthrocarpy are powerful models to elucidate how differences in gene expression of a fruit patterning pathway may result in novel fruit types. Transcriptomes of distal, joint, and proximal regions from Erucaria erucarioides and Cakile lanceolata were analyzed to elucidate within fruit and between species differences in whole transcriptome, gene ontology, and fruit patterning expression profiles. Whole transcriptome expression profiles vary between fruit regions in patterns that are consistent with fruit anatomy. These transcriptomic variances do not correlate with changes in gene ontology, as they remain generally stable within and between both species. Upstream regulators in the fruit patterning pathway, FILAMENTOUS FLOWER and YABBY3, are expressed in the distal and proximal regions of E. erucarioides, but not in the joint, implicating alterations in the pathway in heteroarthrocarpic fruits. Downstream gene, INDEHISCENT, is significantly upregulated in the abscissing joint region of C. lanceolata, which suggests repurposing of valve margin genes for novel joint disarticulation in an otherwise indehiscent fruit. In summary, these data are consistent with modifications in fruit patterning genes producing heteroarthrocarpic fruits through different components of the pathway relative to other indehiscent, non-heteroarthrocarpic, species within the family. Our understanding of fruit development in Arabidopsis is now extended to atypical siliques within the Brassicaceae, facilitating future studies on seed shattering in important Brassicaceous crops and pernicious weeds.
An enhanced heuristic XoR network coding-based method for high quality video streaming over VANETs
(Public Library of Science, 2019-06-28) Mosaarab, Maryam; Barekatain, Behrang; Raahemifar, Kaamran; Movahednejad, Homa
One of the most important challenges in live video streaming in mobile vehicular networks is the optimal use of broadband and point-to-point packet delay. Recent studies show that the sheer use of frames flow compression methods (such as H.264 or HEVC) and the proper communication overlay, such as Peer-to-Peer (P2P), has no absolute influence on increasing the quality of received video in VANET networks. Therefore, the use of an appropriate data exchange method, such as network coding, seems to be of great importance. Compared to Random Network Coding (RNC), XoR Network Coding (XNC) method has the least computational load for the network which is an important factor in optimal use of limited energy of nodes in a wireless network. The basic problem in XNC is that when a node is supposed to combine several frames and transmit them through an encoded frame, how this combination could be made to enable other nodes of the network to be broadcasted through receiving this packet and how can the available packets in their buffers decode as well as extract the largest number of frames in order to experience a higher video quality. To fulfil this aim, an encoding intelligent method is required which is based on the buffers’ status of neighbours. In the proposed method in this article, the best frame combination is reached through buffers status of neighbours and AHP methods or AHP-TOPSIS methods, and the encoded frames are broadcasted through XNC. Simulation results show that due to the reduction in number of transmitted packets in the network, parameters such as congestion and point-to-point delay are significantly reduced and vehicles experience a higher video quality compared with other similar methods.
Spatial optimization for radiation therapy of brain tumours
(Public Library of Science, 2019-06-28) Meaney, Cameron; Stastna, Marek; Kardar, Mehran; Kohandel, Mohammad
Glioblastomas are the most common primary brain tumours. They are known for their highly aggressive growth and invasion, leading to short survival times. Treatments for glioblastomas commonly involve a combination of surgical intervention, chemotherapy, and external beam radiation therapy (XRT). Previous works have not only successfully modelled the natural growth of glioblastomas in vivo, but also show potential for the prediction of response to radiation prior to treatment. This suggests that the efficacy of XRT can be optimized before treatment in order to yield longer survival times. However, while current efforts focus on optimal scheduling of radiotherapy treatment, they do not include a similarly sophisticated spatial optimization. In an effort to improve XRT, we present a method for the spatial optimization of radiation profiles. We expand upon previous results in the general problem and examine the more physically reasonable cases of 1-step and 2-step radiation profiles during the first and second XRT fractions. The results show that by including spatial optimization in XRT, while retaining a constant prescribed total dose amount, we are able to increase the total cell kill from the clinically-applied uniform case.
The Flooring for Injury Prevention (FLIP) Study of complaint flooring for the prevention of fall-related injuries in long-term care: A randomized trial
(Public Library of Science, 2019-06-24) Mackey, Dawn C.; Lachance, Chantelle C.; Wang, Peiwei T.; Feldman, Fabio; Laing, Andrew C.; Leung, Pet M.; Hu, X. Joan; Robinovitch, Stephen N.
Background Fall-related injuries exert an enormous health burden on older adults in long0term care (LTC). Softer landing surfaces, such as those provided by low-stiffness "compliant" flooring, may prevent fall-related injuries by decreasing the forces applied to the body during fall impact. Our primary objective was to assess the clinical effectiveness of compliant flooring at preventing serious fall-related injuries among LTC residents. Methods and findings The Flooring for Injury Prevention (FLIP) Study was a 4-year, randomized superiority trial in 150 single-occupancy resident rooms at a single Canadian LTC site. In April 2013, resident rooms were block randomized (1:1) to installation of intervention compliant flooring (2.54 cm SmartCells) or rigid control flooring (2.54 cm plywood) covered with identical hospital-grade vinyl. The primary outcome was serious fall-related injury over 4 years that required an emergency department visit or hospital admission and a treatment procedure or diagnostic evaluation in hospital. Secondary outcomes included minor fall-related injury, any fall-related injury, falls, and fracture. Outcomes were ascertained by blinded assessors between September 1, 2013 and August 31, 2017 and analyzed by intention to treat. Adverse outcomes were not assessed. During follow-up, 184 residents occupied 74 intervention rooms, and 173 residents occupied 76 control rooms. Residents were 64.3% female with mean (SD) baseline age 81.7 (9.5) years (range 51.1 to 104.6 years), body mass index 25.9 (7.7) kg/m2, and follow-up 1.64 (1.39) years. 1,907 falls were reported; 23 intervention residents experienced 38 serious injuries (from 29 falls in 22 rooms), while 23 control residents experienced 47 serious injuries (from 34 falls in 23 rooms). Compliant flooring did not affect odds of ≥1 serious fall-related injury (12.5% intervention versus 13.3% control, odds ratio [OR]: 0.98, 95% CI: 0.52 to 1.84, p = 0.950) or ≥2 serious fall-related injuries (5.4% versus 7.5%, OR: 0.74, 95% CI: 0.31 to 1.75, p = 0.500). Compliant flooring did not affect rate of serious fall-related injuries (0.362 versus 0.422 per 1,000 bed nights, rate ratio [RR]: 1.04, 95% CI: 0.45 to 2.39, p = 0.925; 0.038 versus 0.053 per fall, RR: 0.81, 95% CI: 0.38 to 1.71, p = 0.560), rate of falls with ≥1 serious fall-related injury (0.276 versus 0.303 per 1,000 bed nights, RR: 0.97, 95% CI: 0.52 to 1.79, p = 0.920), or time to first serious fall-related injury (0.237 versus 0.257, hazard ratio [HR]: 0.92, 95% CI: 0.52 to 1.62, p = 0.760). Compliant flooring did not affect any secondary outcome in this study. Study limitations included the following: findings were specific to 2.54 cm SmartCells compliant flooring installed in LTC resident rooms, standard fall and injury prevention interventions were in use throughout the study and may have influenced the observed effect of compliant flooring, and challenges with concussion detection in LTC residents may have prevented estimation of the effect of compliant flooring on fall-related concussions. Conclusions In contrast to results from previous retrospective and nonrandomized studies, this study found that compliant flooring underneath hospital-grade vinyl was not effective at preventing serious fall-related injuries in LTC. Future studies are needed to identify effective methods for preventing fall-related injuries in LTC.
Re-evaluating whether bilateral eye movements influence memory retrieval
(Public Library of Science, 2020-01-27) Roberts, Brady R. T.; Fernandes, Myra A.; MacLeod, Colin M.
Several recent studies have reported enhanced memory when retrieval is preceded by repetitive horizontal eye movements, relative to vertical or no eye movements. The reported memory boost has been referred to as the Saccade-Induced Retrieval Enhancement (SIRE) effect. Across two experiments, memory performance was compared following repetitive horizontal or vertical eye movements, as well as following a control condition of no eye movements. In Experiment 1, we conceptually replicated Christman and colleagues’ seminal study, finding a statistically significant SIRE effect, albeit with weak Bayesian evidence. We therefore sought to conduct another close extension. In Experiment 2, horizontal and vertical eye movement conditions were manipulated separately, and sample size was increased. No evidence of a SIRE effect was found: Bayesian statistical analyses demonstrated significant evidence for a null effect. Taken together, these experiments suggest that the SIRE effect is inconsistent. The current experiments call into question the generalizability of the SIRE effect and suggest that its presence is very sensitive to experimental design. Future work should further assess the robustness of the effect before exploring related theories or underlying mechanisms.
Young women's reproductive health conversations: Roles of maternal figures and clinical practices
(Public Library of Science, 2020-01-23) Richards, Nicole K.; Crockett, Elizabeth; Morley, Christopher P.; Levandowski, Brooke A.
Objective To explore the role of clinical providers and mothers on young women's ability to have confidential, candid reproductive health conversations with their providers. Methods We conducted 14 focus groups with 48 women aged 15-28 years (n = 9), and 32 reproductive healthcare workers (n = 5). Focus groups were audio recorded and transcribed. Data were analyzed using inductive coding and thematic analyses. We examined findings through the lens of paternalism, a theory that illustrates adults' role in children's autonomy and wellbeing. Results Mothers have a substantial impact on young women's health values, knowledge, and empowerment. Young women reported bringing information from their mothers into patient-provider health discussions. Clinical best practices included intermingled components of office policies, state laws, and clinical guidelines, which supported health workers' actions to have confidential conversations. There were variations in how health workers engaged young women in a confidential conversation within the exam room. Conclusions Both young women and health workers benefit from situations in which health workers firmly ask the parent to leave the exam room for a private conversation with the patient. Young women reported this improves their comfort in asking the questions they need to make the best decision for themselves. Clinic leadership needs to ensure that confidentiality surrounding young women's reproductive health is uniform throughout their practice and integrated into patient flow.

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