Communication in Immersive Social Virtual Reality: A Systematic Review of 10 Years' Studies

As virtual reality (VR) technologies have improved in the past decade, more research has investigated how they could support more effective communication in various contexts to improve collaboration and social connectedness. However, there was no literature to summarize the uniqueness VR provided and put forward guidance for designing social VR applications for better communication. To understand how VR has been designed and used to facilitate communication in different contexts, we conducted a systematic review of the studies investigating communication in social VR in the past ten years by following the PRISMA guidelines. We highlight current practices and challenges and identify research opportunities to improve the design of social VR to better support communication and make social VR more accessible.Comment: Chinese CHI '22: The Tenth International Symposium of Chinese CHI (Chinese CHI 2022

Rhodioloside inhibits apoptosis of hippocampal neurons exposed to sevoflurane via cAMP/PKA signaling pathway

Purpose: Neural injury affects patients after using inhalational anesthetics such as sevoflurane. Rhodioloside, a compound which is obtained from the Rhodiola rosea plant has been implicated to be the most commonly used psychostimulant that can improve a range of conditions. The study was aimed at finding the molecular mechanism underlying the Rhodioloside treatment of sevoflurane-injured hippocampal neurons.Methods: Main hippocampal neurons, secluded from Sprague Dawley embryonic rats were employed to create an injury model using 3 % sevoflurane. The sevoflurane-injured hippocampal neurons were treated with varying concentrations (10, 20, 40 and 80 μM/ml) of Rhodioloside to create different experimental groups: RHSD10+SEV, RHSD20+SEV, RHSD40+SEV, RHSD80+SEV, while untreated cells were considered as the Control group. Cell viability was identified using the CCK-8 assay. The CFSE assay was used to verify the promotion function of Rhodioloside on cell differentiation of neurons. FCM assay was employed to determine cell proliferation and apoptosis. Expression levels of apoptosisrelated factors, like Caspase-3, Bcl-2 and Bax were examined by RT-qPCR, while Western blot was used to measure phosphorylation of PKA.Results: Rhodioloside stimulated cell viability and prevented cell apoptosis in sevoflurane-injured hippocampal neurons in doses between 10-80 μM. The apoptosis-inhibitory effect of Rhodioloside was observed to be through cAMP/PKA pathway activation. Also, expression levels of Bcl-2, and PKA were enhanced and the level of Caspase-3 and Bax was reduced in a dose-dependent pattern. The PKA inhibitor reversed the above observation in the 40 μM Rhodioloside-treatment.Conclusion: Rhodioloside promoted cell viability and prevented apoptosis of primary hippocampal neurons injured by sevoflurane, through cAMP/PKA pathway activation. Inhibition of PKA network deteriorated the function of Rhodioloside by stimulating cell apoptosis. Our findings present a novel evidence that Rhodioloside could attenuate neurotoxicity of inhalational anesthetics. Keywords: Cell apoptosis, cAMP/PKA pathway, Hippocampal neurons, Rhodioloside, Sevofluran

Active Open-Vocabulary Recognition: Let Intelligent Moving Mitigate CLIP Limitations

Active recognition, which allows intelligent agents to explore observations for better recognition performance, serves as a prerequisite for various embodied AI tasks, such as grasping, navigation and room arrangements. Given the evolving environment and the multitude of object classes, it is impractical to include all possible classes during the training stage. In this paper, we aim at advancing active open-vocabulary recognition, empowering embodied agents to actively perceive and classify arbitrary objects. However, directly adopting recent open-vocabulary classification models, like Contrastive Language Image Pretraining (CLIP), poses its unique challenges. Specifically, we observe that CLIP's performance is heavily affected by the viewpoint and occlusions, compromising its reliability in unconstrained embodied perception scenarios. Further, the sequential nature of observations in agent-environment interactions necessitates an effective method for integrating features that maintains discriminative strength for open-vocabulary classification. To address these issues, we introduce a novel agent for active open-vocabulary recognition. The proposed method leverages inter-frame and inter-concept similarities to navigate agent movements and to fuse features, without relying on class-specific knowledge. Compared to baseline CLIP model with 29.6% accuracy on ShapeNet dataset, the proposed agent could achieve 53.3% accuracy for open-vocabulary recognition, without any fine-tuning to the equipped CLIP model. Additional experiments conducted with the Habitat simulator further affirm the efficacy of our method

A Decentralized Virtual Machine Migration Approach of Data Centers for Cloud Computing

As cloud computing offers services to lots of users worldwide, pervasive applications from customers are hosted by large-scale data centers. Upon such platforms, virtualization technology is employed to multiplex the underlying physical resources. Since the incoming loads of different application vary significantly, it is important and critical to manage the placement and resource allocation schemes of the virtual machines (VMs) in order to guarantee the quality of services. In this paper, we propose a decentralized virtual machine migration approach inside the data centers for cloud computing environments. The system models and power models are defined and described first. Then, we present the key steps of the decentralized mechanism, including the establishment of load vectors, load information collection, VM selection, and destination determination. A two-threshold decentralized migration algorithm is implemented to further save the energy consumption as well as keeping the quality of services. By examining the effect of our approach by performance evaluation experiments, the thresholds and other factors are analyzed and discussed. The results illustrate that the proposed approach can efficiently balance the loads across different physical nodes and also can lead to less power consumption of the entire system holistically

Synapse: Interactive Guidance by Demonstration with Trial-and-Error Support for Older Adults to Use Smartphone Apps

As smartphones are widely adopted, mobile applications (apps) are emerging to provide critical services such as food delivery and telemedicine. While bring convenience to everyday life, this trend may create barriers for older adults who tend to be less tech-savvy than young people. In-person or screen sharing support is helpful but limited by the help-givers' availability. Video tutorials can be useful but require users to switch contexts between watching the tutorial and performing the corresponding actions in the app, which is cumbersome to do on a mobile phone. Although interactive tutorials have been shown to be promising, none was designed for older adults. Furthermore, the trial-and-error approach has been shown to be beneficial for older adults, but they often lack support to use the approach. Inspired by both interactive tutorials and trial-and-error approach, we designed an app-independent mobile service, \textit{Synapse}, for help-givers to create a multimodal interactive tutorial on a smartphone and for help-receivers (e.g., older adults) to receive interactive guidance with trial-and-error support when they work on the same task. We conducted a user study with 18 older adults who were 60 and over. Our quantitative and qualitative results show that Synapse provided better support than the traditional video approach and enabled participants to feel more confident and motivated. Lastly, we present further design considerations to better support older adults with trial-and-error on smartphones

Same Environment, Stratified Impacts? Air Pollution, Extreme Temperatures, and Birth Weight in South China

This paper investigates whether associations between birth weight and prenatal ambient environmental conditions—pollution and extreme temperatures—differ by 1) maternal education; 2) children’s innate health; and 3) interactions between these two. We link birth records from Guangzhou, China, during a period of high pollution, to ambient air pollution (PM10 and a composite measure) and extreme temperature data. We first use mean regressions to test whether, overall, maternal education is an “effect modifier” in the relationships between ambient air pollution, extreme temperature, and birth weight. We then use conditional quantile regressions to test for effect heterogeneity according to the unobserved innate vulnerability of babies after conditioning on other confounders. Results show that 1) the negative association between ambient exposures and birth weight is twice as large at lower conditional quantiles of birth weights as at the median; 2) the protection associated with college-educated mothers with respect to pollution and extreme heat is heterogeneous and potentially substantial: between 0.02 and 0.34 standard deviations of birth weights, depending on the conditional quantiles; 3) this protection is amplified under more extreme ambient conditions and for infants with greater unobserved innate vulnerabilities

Combat molten aluminum corrosion of AISI H13 steel by lowtemperature liquid nitrocarburizing

Possibility of improving the resistance of AISI H13 steel to molten aluminum corrosion by liquid nitrocarburizing (LNC) was explored. The effects of the LNC parameters in terms of temperatures (703/723/743K) and soaking time (4/8/12h) on phase transformation, microstructure, and resistance to molten aluminum were fully studied. The surface phase compositions and the cross-sectional phase distribution of the LNC treated specimens were studied by implementable X-ray diffraction analysis. Microstructure, element distribution, microhardness, and the kinetics of the nitrocarburized case formation were fully researched. Immersion test of corrosion resistance to molten aluminum was carried out at 1023K for 30min. It is observed that an oxide layer can be produced on the top of the nitrocarburized case during LNC treatment, which cannot be regularly produced by other nitriding methods. The nitrocarburized case consists of a compound layer, a diffusion layer, and a transition layer. The growth of the nitrocarburized case is proportional to the squared treatment time and follows the Arrhenius law for the treatment temperature. The activation energy is estimated to be 195.4 kJ·mol−1. While the nitrocarburized case provided limited resistance to molten aluminum, the oxide layer formed on the top of the nitrocarburized case conferred significantly improved molten aluminum corrosion resistance, especially a duplex oxide layer produced at 743

An Image Filter Based on Shearlet Transformation and Particle Swarm Optimization Algorithm

Digital image is always polluted by noise and made data postprocessing difficult. To remove noise and preserve detail of image as much as possible, this paper proposed image filter algorithm which combined the merits of Shearlet transformation and particle swarm optimization (PSO) algorithm. Firstly, we use classical Shearlet transform to decompose noised image into many subwavelets under multiscale and multiorientation. Secondly, we gave weighted factor to those subwavelets obtained. Then, using classical Shearlet inverse transform, we obtained a composite image which is composed of those weighted subwavelets. After that, we designed fast and rough evaluation method to evaluate noise level of the new image; by using this method as fitness, we adopted PSO to find the optimal weighted factor we added; after lots of iterations, by the optimal factors and Shearlet inverse transform, we got the best denoised image. Experimental results have shown that proposed algorithm eliminates noise effectively and yields good peak signal noise ratio (PSNR)

Exploring the Opportunity of Augmented Reality (AR) in Supporting Older Adults Explore and Learn Smartphone Applications

The global aging trend compels older adults to navigate the evolving digital landscape, presenting a substantial challenge in mastering smartphone applications. While Augmented Reality (AR) holds promise for enhancing learning and user experience, its role in aiding older adults' smartphone app exploration remains insufficiently explored. Therefore, we conducted a two-phase study: (1) a workshop with 18 older adults to identify app exploration challenges and potential AR interventions, and (2) tech-probe participatory design sessions with 15 participants to co-create AR support tools. Our research highlights AR's effectiveness in reducing physical and cognitive strain among older adults during app exploration, especially during multi-app usage and the trial-and-error learning process. We also examined their interactional experiences with AR, yielding design considerations on tailoring AR tools for smartphone app exploration. Ultimately, our study unveils the prospective landscape of AR in supporting the older demographic, both presently and in future scenarios

Intravenous tPA therapy does not worsen acute intracerebral hemorrhage in mice

Tissue plasminogen activator (tPA) is the only FDA-approved treatment for reperfusing ischemic strokes. But widespread use of tPA is still limited by fears of inadvertently administering tPA in patients with intracerebral hemorrhage (ICH). Surprisingly, however, the assumption that tPA will worsen ICH has never been biologically tested. Here, we assessed the effects of tPA in two models of ICH. In a mouse model of collagenase-induced ICH, hemorrhage volumes and neurological deficits after 24 hrs were similar in saline controls and tPA-treated mice, whereas heparin-treated mice had 3-fold larger hematomas. In a model of laser-induced vessel rupture, tPA also did not worsen hemorrhage volumes, while heparin did. tPA is known to worsen neurovascular injury by amplifying matrix metalloproteinases during cerebral ischemia. In contrast, tPA did not upregulate matrix metalloproteinases in our mouse ICH models. In summary, our experimental data do not support the assumption that intravenous tPA has a deleterious effect in acute ICH. However, due to potential species differences and the inability of models to fully capture the dynamics of human ICH, caution is warranted when considering the implications of these findings for human therapy