55 research outputs found
From Capture to Display: A Survey on Volumetric Video
Volumetric video, which offers immersive viewing experiences, is gaining
increasing prominence. With its six degrees of freedom, it provides viewers
with greater immersion and interactivity compared to traditional videos.
Despite their potential, volumetric video services poses significant
challenges. This survey conducts a comprehensive review of the existing
literature on volumetric video. We firstly provide a general framework of
volumetric video services, followed by a discussion on prerequisites for
volumetric video, encompassing representations, open datasets, and quality
assessment metrics. Then we delve into the current methodologies for each stage
of the volumetric video service pipeline, detailing capturing, compression,
transmission, rendering, and display techniques. Lastly, we explore various
applications enabled by this pioneering technology and we present an array of
research challenges and opportunities in the domain of volumetric video
services. This survey aspires to provide a holistic understanding of this
burgeoning field and shed light on potential future research trajectories,
aiming to bring the vision of volumetric video to fruition.Comment: Submitte
2-Amino-nicotinamide induces apoptosis of prostate cancer cells via inhibition of PI3K/AKT and phosphorylation of STA3/JAK2
Purpose: To study the cytotoxicity of 2-amino-nicotinamide against prostate cancer (PCa) cells, and the underlying molecular mechanism.Methods: The effect of 2-amino-nicotinamide on cell viability and apoptosis was determined by 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) and flow cytometry, respectively, while its effect on cellular production of fluorescent-oxidized product from DCFH-DA was measured using flow cytometry. Apoptosis-related protein expressions were evaluated by western blot assay.Results: 2-Amino-nicotinamide produced cytotoxicity against MCF-7, SGC7901, PCa 22Rv1 and LNCaP cancer cell lines (p < 0.05). Mechanistic data revealed that 2-amino-nicotinamide activated apoptosis, and enhanced cleavage of PARP and caspase-3 in PCa 22Rv1 and LNCaP cells. In PCa 22Rv1 and LNCaP cell lines, cytochrome C and Bax levels were enhanced by treatment with 2-aminonicotinamide, while Bcl-2 protein level was suppressed (p < 0.05). Activated expressions of PI3K, Akt and ERK in PCa 22Rv1 and LNCaP cells were down-regulated, while p38 expression was increased.Moreover, 2-amino-nicotinamide suppressed the activation of JAK2 and STAT3, but did not alter total JAK2 and STAT3 levels in PCa 22Rv1 and LNCaP cells (p < 0.05).Conclusion: 2-Amino-nicotinamide exerts cytotoxic effects on prostate carcinoma cells via activation of apoptosis and down-regulation of PI3K/AKT and STA3/JAK2. Thus, 2-amino nicotinamide is a potential bioactive agent for prostate cancer management.
Keywords: 2-Amino-nicotinamide, Apoptosis, Fluorescent-oxidized, Cytotoxicit
Understanding User Behavior in Volumetric Video Watching: Dataset, Analysis and Prediction
Volumetric video emerges as a new attractive video paradigm in recent years
since it provides an immersive and interactive 3D viewing experience with six
degree-of-freedom (DoF). Unlike traditional 2D or panoramic videos, volumetric
videos require dense point clouds, voxels, meshes, or huge neural models to
depict volumetric scenes, which results in a prohibitively high bandwidth
burden for video delivery. Users' behavior analysis, especially the viewport
and gaze analysis, then plays a significant role in prioritizing the content
streaming within users' viewport and degrading the remaining content to
maximize user QoE with limited bandwidth. Although understanding user behavior
is crucial, to the best of our best knowledge, there are no available 3D
volumetric video viewing datasets containing fine-grained user interactivity
features, not to mention further analysis and behavior prediction. In this
paper, we for the first time release a volumetric video viewing behavior
dataset, with a large scale, multiple dimensions, and diverse conditions. We
conduct an in-depth analysis to understand user behaviors when viewing
volumetric videos. Interesting findings on user viewport, gaze, and motion
preference related to different videos and users are revealed. We finally
design a transformer-based viewport prediction model that fuses the features of
both gaze and motion, which is able to achieve high accuracy at various
conditions. Our prediction model is expected to further benefit volumetric
video streaming optimization. Our dataset, along with the corresponding
visualization tools is accessible at
https://cuhksz-inml.github.io/user-behavior-in-vv-watching/Comment: Accepted by ACM MM'2
LiveVV: Human-Centered Live Volumetric Video Streaming System
Volumetric video has emerged as a prominent medium within the realm of
eXtended Reality (XR) with the advancements in computer graphics and depth
capture hardware. Users can fully immersive themselves in volumetric video with
the ability to switch their viewport in six degree-of-freedom (DOF), including
three rotational dimensions (yaw, pitch, roll) and three translational
dimensions (X, Y, Z). Different from traditional 2D videos that are composed of
pixel matrices, volumetric videos employ point clouds, meshes, or voxels to
represent a volumetric scene, resulting in significantly larger data sizes.
While previous works have successfully achieved volumetric video streaming in
video-on-demand scenarios, the live streaming of volumetric video remains an
unresolved challenge due to the limited network bandwidth and stringent latency
constraints. In this paper, we for the first time propose a holistic live
volumetric video streaming system, LiveVV, which achieves multi-view capture,
scene segmentation \& reuse, adaptive transmission, and rendering. LiveVV
contains multiple lightweight volumetric video capture modules that are capable
of being deployed without prior preparation. To reduce bandwidth consumption,
LiveVV processes static and dynamic volumetric content separately by reusing
static data with low disparity and decimating data with low visual saliency.
Besides, to deal with network fluctuation, LiveVV integrates a volumetric video
adaptive bitrate streaming algorithm (VABR) to enable fluent playback with the
maximum quality of experience. Extensive real-world experiment shows that
LiveVV can achieve live volumetric video streaming at a frame rate of 24 fps
with a latency of less than 350ms
Fault-tolerant evolvable hardware using field-programmable transistor arrays
The paper presents an evolutionary approach to the design of fault-tolerant VLSI (very large scale integrated) circuits using EHW (evolvable hardware). The EHW research area comprises a set of applications where GA (genetic algorithms) are used for the automatic synthesis and adaptation of electronic circuits. EHW is particularly suitable for applications requiring changes in task requirements and in the environment or faults, through its ability to reconfigure the hardware structure dynamically and autonomously. This capacity for adaptation is achieved via the use of GA search techniques, in our experiments, a fine-grained CMOS (complementary metal-oxide silicon) FPTA (field-programmable FPGA transistor array) architecture is used to synthesize electronic circuits. The FPTA is a reconfigurable architecture, programmable at the transistor level and specifically designed for EHW applications. The paper demonstrates the power of EA to design analog and digital fault-tolerant circuits. It compares two methods to achieve fault-tolerant design, one based on fitness definition and the other based on population. The fitness approach defines, explicitly, the faults that the component can encounter during its life, and evaluates the average behavior of the individuals. The population approach, on the other hand, uses the implicit information of the population statistics accumulated by the GA over many generations. The paper presents experiment results obtained using both approaches for the synthesis of a fault-tolerant digital circuit (XNOR) and a fault-tolerant analog circuit (multiplier)
Modelling the microclimate in a conical bottomed circular grain silo
A three-dimensional mathematical model for predicting the behaviour of microclimate
in the stored grain silo is presented. This analysis is implemented by calculating the air
pressure field within an aerated conical bottomed circular silo, to continuing prediction
the velocity field. The obtaining results are used to compute the simultaneous heat and
mass transfer processes that occur in non-aerated and aerated grain silos. The
conservation equations of momentum, mass and energy are employed in this study. The
numerical scheme is based on applying a mapping technique with an algebraic grid
generation method, to discretise the governing equations in the arbitrary geometries that
describe the grain stores.
The finite different solution of the governing equations are obtained by using
Alternating Direction Implicit method, Thomas algorithm and explicit method. The
numerical experiments have been performed to investigate the effects of the nonuniform
grid size, time step, duct shape and placement. Results in graphical form are
presented for the pressure, velocity, temperature, moisture content, absolute humidity,
wet bulb temperature, dry matter loss, seed viability and pesticide decay.
Significantly, a novel configuration of an annular aeration duct and a traditional linear
aeration duct in farm silos have been investigated. It was found that the annular
aeration system provides uniform airflow results in better protection of the stored grains
than in the linear aeration system, in that the beneficial grain quality indices remain
high, and the rate of growth of insect population is retarded.
An outcome of the research has been improved the designs of commercially available
grain silos
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