We investigate the thermally induced morphological and crystalline development of methylammonium lead mixed halide perovskite (CH3NH3PbI3–x Cl x ) thin films and photovoltaic device performance with ...meso-superstructured and planar heterojunction architectures. We observe that a short rapid thermal annealing at 130 °C leads to the growth of large micron-sized textured perovskite domains and improved the short circuit currents and power conversion efficiencies up to 13.5% for the planar heterojunction perovskite solar cells. This work highlights the criticality of controlling the thin film crystallization mechanism of hybrid perovskite materials for high-performing photovoltaic applications.
Sexually transmitted infections (STIs) and HIV disproportionately affect young persons; gay, bisexual and other men who have sex with men (GBMSM) and transgender women; persons of colour; and the ...U.S. South. Complex issues contribute to these high STI/HIV rates. Our community‐based participatory research (CBPR) partnership conducted a community‐driven needs assessment to inform an intervention addressing STI/HIV disparities and related social determinants of health (SDH) among young GBMSM and transgender women of colour in a high‐incidence STI/HIV community in North Carolina. In 2018, in‐depth interviews were conducted with 21 community members and 29 community organisation representatives to explore needs, priorities and assets. Interview data were analysed using constant comparison, an approach to grounded theory, and an empowerment theory‐based planning process was used to develop multilevel intervention strategies based on findings. Thirteen themes emerged from the interviews that were organised into five domains: health (e.g., limited health services use; need for lesbian, gay, bisexual and transgender LGBT‐friendly providers; prioritisation of mental health and gender transition and limited knowledge of and access to pre‐exposure prophylaxis PrEP for HIV); employment (e.g., employment as a priority and relying on sex work to ‘make ends meet’); education (e.g., barriers to education and needs for training to improve employment opportunities); social support (e.g., few welcoming activities and groups; strong informal support networks and little interaction between GBMSM and transgender women) and discrimination (e.g., frequent experiences of discrimination and the impact of frontline staff on services use). Three strategies – community‐based peer navigation, use of social media, and anti‐discrimination trainings for organisations – were identified and integrated into a new intervention known as Impact Triad. CBPR was successfully applied to identify needs, priorities and assets and develop a multilevel intervention focused on health disparities and SDH among young GBMSM and transgender women of colour in the U.S. South.
Abstract only
Background
Screen time and physical inactivity have dramatically increased in the last 20 yrs contributing to the obesity epidemic. Children now report upwards of 4 hours of game ...playing per day occupying time previously spent active.
Purpose
To examine the physiological responses to playing active video games (AVG), walking, and watching television.
Methods
Twenty youth with severe obesity (11–17 yrs.) were recruited and tested at the Healthy Lifestyle Clinic at Le Bonheur Children's Hospital. A counterbalanced, crossover design was used. Following a familiarization period with the Kinect, participants completed six randomized conditions: 1) walking on a treadmill at a self‐selected speed (TM), 2) watching television (TV), 3) Fitnexx, 4) river rush (RRH), 5) reflex ridge (RFR), and 6) space pop (SP). RRH, RFR, and SP are mini games within
Kinect Adventures
!, an active video game for the Xbox 360. Fitnexx is a prototype active video game. Conditions lasted ten minutes with a washout period of five minutes between each condition. Heart rate (HR), ΔHR, respiratory rate (RR), rating of perceived exertion (RPE), activity level, and posture were recorded for each condition. Physiological responses were recorded in 15 second intervals using a wireless physiological monitor (BioHarness 3 by Zephyr Performance Systems). Repeated‐measures ANOVA (with Bonferroni correction) was used to examine condition differences.
Results
Twenty patients (13.3 ± 2.1 yrs., 163.7 ± 0.1 cm, 104.8 ± 28.1 kg, and 38.7 ± 7.9 BMI) completed the study. Activity during Fitnexx (0.63 ± 0.19 g) was significantly higher than all other conditions and approached a high activity level (i.e. run). Activity during TV (0.02 ± 0.01 g) was significantly lower than all conditions and considered a static activity level. TM (0.21 ± 0.04 g), RRH (0.28 ± 0.06 g), RFR (0.3 ± 0.07 g), and SP (0.2 ± 0.05 g) were moderate activity levels (i.e. walk). HR for Fitnexx (156.8 ± 12.5 bpm) was significantly higher than all other conditions. HR during TV (92.3 ± 14.9 bpm) was significantly lower than all conditions. The difference between TM (117.2 ± 18.3 bpm), RRH (128 ± 18.8 bpm), RFR (127.4 ± 17.9 bpm), and SP (121.5 ± 17.4 bpm) was not significant. ΔHR for Fitnexx (66.3 ± 13.8 bpm) was significantly higher than all other conditions. ΔHR during TV (−5.1 ± 16.5 bpm) was significantly lower than all conditions. The difference between TM (24.9 ± 11.7 bpm), RR (33.6 ± 11.8 bpm), RFR (37.3 ± 10.2 bpm), and SP (29.7 ± 8.9 bpm) was not significant. RR during TM (38.7 ± 6.1 bpm) was significantly higher than Fitnexx (29.3 ± 3.4 bpm). RR during TV (10.9 ± 4.8 bpm) was significantly lower than all conditions. RR during RRH (24.5 ± 2.7 bpm) and SP (24 ± 4.2 bpm) was not significantly different. RPE for Fitnexx (5.3 ± 3.5) was significantly higher than all other conditions. RPE during TV (0.1 ± 0.4) was significantly lower than all conditions. RPE during SP (1.4 ± 1.3) was similar to TM (1.5 ± 1.9), RRH (2.3 ± 1.8), and RFR (3.2 ± 2.6). Patients reported greater interest and enjoyment in AVG trials than walking.
Conclusion
AVG can increase energy expenditure and activity levels in children and adolescents with obesity. The individual movement patterns driven by story lines influence responses which may inform use in targeted exercise prescriptions. Our results support the use of AVG as a therapeutic tool to improve health and quality of life including cardiovascular fitness, muscular strength, and body awareness.
Support or Funding Information
Collaborative Research Network (CORNET) Award. University of Tennessee Health Science Center. 2016
The purpose of this study was to examine the physiological responses to playing different active video games (AVG), as well as document the activity level exerted during AVG in relation to treadmill ...walking (TM) and watching television (TV). 20 youth (age 11–17 yr) with obesity were recruited from the Healthy Lifestyle Clinic and underwent testing under six randomized conditions: 1) TM, 2) TV, 3) Fitnexx, 4) river rush (RRH), 5) reflex ridge (RFR), and 6) space pop (SP). RRH, RFR, and SP are active video games for the Xbox 360. Fitnexx is a prototype AVG. Each test lasted approximately ten minutes each with ten minutes between conditions and participants wore a wireless physiological monitor (Zephyr BioHarness™3) for all tests. Physical activity was assessed via accelerometer, along with heart rate (HR). Rating of Perceived Exertion (RPE) was also gathered for each condition. Repeated-measures ANOVA examined condition differences. Subjects were age 13.3 ± 2.1 years old with BMI 38.7 ± 7.9 (kg·m·s
−2
). Fitnexx had the highest activity level (0.63 ± 0.19g ~ jog), while activity levels for TM (0.20 ± 0.04g), RRH (0.29 ± 0.05g), RFR (0.31 ± 0.07g), and SP (0.21 ± 0.05g) were moderate (~walk),
Ps
< 0.05. Fitnexx had the highest HR (157 ± 13 bpm;
Ps
< 0.001), compared to TM (117 ± 18 bpm), RRH (128 ± 19 bpm), RFR (127 ± 18 bpm), and SP (122 ± 17 bpm), which were statistically similar. Rating of Perceived Exertion (RPE) was highest for Fitnexx (5 ± 4 RPE) compared to TM (2 ± 1 RPE) on 0–10 scale. TV had lowest activity, HR, and RPE (
p
< 0.04). Given these results, AVG can increase activity levels in youth with obesity and has potential as a therapeutic tool for obese children.
In the United States, transgender women are disproportionately affected by HIV. However, few evidence-based prevention interventions exist for this key population. We describe two promising, locally ...developed interventions that are currently being implemented and evaluated through the Centers for Disease Control and Prevention Combination HIV Prevention for Transgender Women Project: (a) ChiCAS, designed to promote the uptake of pre-exposure prophylaxis (PrEP), condom use, and medically supervised hormone therapy among Spanish-speaking transgender Latinas, and (b) TransLife Care, designed to address the structural drivers of HIV risk through access to housing, employment, legal services, and medical services, including HIV preventive care (e.g., PrEP use) among racially/ethnically diverse urban transgender women. If the evaluation trials determine that these interventions are effective, they will be among the first such interventions for use with transgender women incorporating PrEP, thereby contributing to the evidence-based resources that may be used to reduce HIV risk among this population.
Determining the root cause of performance regression for microservices is challenging. The topological cascading performance implications among microservices hide the source of the problem. ...Additionally, the lack of knowledge about application phases can potentially lead to false-positive critical service detection. Service resource utilization is an imperfect proxy for application performance, potentially leading to false positives. Therefore, in this work, we propose a new performance testing framework that leverages hidden Berkeley Packet Filter (BPF) kernel metrics to locate root causes of performance regression. The framework applies a systematic multi-level approach to analyze microservice performance without intrusive code instrumentation. First, the framework constructs an attributed graph with microservice requests, scores the services to identify the critical paths, and ranks the low-level metrics to highlight the root cause of performance regression. Through judiciously designed experiments, we evaluated the metric collection overhead, showing less than 18% more latency when the application is running across hosts and 9% within the same host. In addition, depending on the application, no overhead is experienced, while the state-of-the-art approach presented up to 1060% more latency. The microservice benchmark evaluation shows that MicroLens can successfully identify the set of root causes and that the causes vary when the application is running in different infrastructures.
This study explores digital media-based design that facilitates event-driven collaboration. The research focus is to identify the design necessary to create features, applications and a rich ...collaborative environment that engages users and aligns participation to achieve tangible outcomes beyond content creation. Media theorist Clay Shirky writes of a different world because social tools are removing the obstacles of collective actions. In the absence of these obstacles, natural occurrences of collective efforts and community based-efforts are emerging. This study proposes a new design perspective and attention to facilitation that affords these collective actions. It develops a model that identifies critical elements in the design of a collaborative environment, and a communication discipline that facilitates a deeper level of connectivity. This work distinguishes between a network of friends and the coordination of a collaborative community formed to accomplish a task. The research explores the stages of creating an event, in the moment design to tailor the collaborative environment to achieve the expectations of the participants, and a design perspective that emphasizes the stakeholders. A predictable collaborative effort can be facilitated by designing to the group process and by utilizing dialogic elements to capture the attributes of online, social media and to create events. To design a digital collaborative environment, there are three areas identified as instrumental. The three areas that must be reconsidered and reestablished to support a new collaborative environment include full-representation opposed to equal-participation, relevance in place of interests, and new definitions of “enrolled,” “participation,” and “contributor” which indicates a type of information instead of a degree of contribution. The digital collaborative environment proposed accommodates a dedicated community with a published vision and purpose, and provides the tools that enable actions toward an event that reflects the shared mission of the group. The unique aspect of this study is rethinking collaboration with an emphasis on communication and design that highlights, promotes and facilitates the development of new ideas that today get lost as simple posts.
Containerization and application variety bring many challenges in automating evaluations for performance tuning and comparison among infrastructure choices. Due to the tightly-coupled design of ...benchmarks and evaluation tools, the present automated tools on Kubernetes are limited to trivial microbenchmarks and cannot be extended to complex cloudnative architectures such as microservices and serverless, which are usually managed by customized operators for setting up workload dependencies. In this paper, we propose AutoDECK, a performance evaluation framework with a fully declarative manner. The proposed framework automates configuring, deploying, evaluating, summarizing, and visualizing the benchmarking workload. It seamlessly integrates mature Kubernetes-native systems and extends multiple functionalities such as tracking the image-build pipeline, and auto-tuning. We present five use cases of evaluations and analysis through various kinds of bench-marks including microbenchmarks and HPC/AI benchmarks. The evaluation results can also differentiate characteristics such as resource usage behavior and parallelism effectiveness between different clusters. Furthermore, the results demonstrate the benefit of integrating an auto-tuning feature in the proposed framework, as shown by the 10% transferred memory bytes in the Sysbench benchmark.
Containerization on the cloud offers several crucial benefits. However, these benefits are negated by the effects of virtual network stack and address encapsulation, especially for workloads that ...require intense communication. Socket replacement is a promising approach to breach this wall without changing the underlay infrastructure by replacing a nested network stack with a simple host network stack. Current state-of-the-art approaches perform this replacement by preloading the overridden socket library in a containerized process. However, the preloading approach requires user effort to modify the deploying manifests and a compromised security policy configuration of privileged containers to access the host namespace. This paper introduces a new replacement framework where a secured control plane agent performs the replacement by utilizing low-overhead BPF kernel tracing technology. As a result, containers can obtain host-native network performance and neither modification nor escalated privileges are required for user containers. Experiments on multiple benchmarks including iPerf, MPI, memslap, and GROMACS have been conducted to confirm efficacy.
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