Packet-based Hierarchal Soft Shadow Mapping

International audienceRecent soft shadow mapping techniques based on back-projection can render high quality soft shadows in real time. However, real time high quality rendering of large penumbrae is still challenging, especially when multi-layer shadow maps are used to reduce single light sample silhouette artifact. In this paper, we present an efficient algorithm to attack this problem. We first present a GPU-friendly packet-based approach rendering a packet of neighboring pixels together to amortize the cost of computing visibility factors. Then, we propose a hierarchical technique to quickly locate the contour edges, further reducing the computation cost. At last, we suggest a multi-view shadow map approach to reduce the single light sample artifact. We also demonstrate its higher image quality and higher efficiency compared to the existing depth peeling approaches

Predicted Virtual Soft Shadow Maps with High Quality Filtering

International audienceIn this paper we present a novel image based algorithm to render visually plausible anti-aliased soft shadows in a robust and efficient manner. To achieve both high visual quality and high performance, it employs an accurate shadow map filtering method which guarantees smooth penumbrae and high quality anisotropic anti-aliasing of the sharp transitions. Unlike approaches based on pre-filtering approximations, our approach does not suffer from light bleeding or losing contact shadows. Discretization artefacts are avoided by creating virtual shadow maps on the fly according to a novel shadow map resolution prediction model. This model takes into account the screen space frequency of the penumbrae via a perceptual metric which has been directly established from an appropriate user study. Consequently, our algorithm always generates shadow maps with minimal resolutions enabling high performance while guarantying high quality. Thanks to this perceptual model, our algorithm can sometimes be faster at rendering soft shadows than hard shadows. It can render game-like scenes at very high frame rates, and extremely large and complex scenes such as CAD models at interactive rates. In addition, our algorithm is highly scalable, and the quality versus performance trade-off can be easily tweaked

Cathepsin B-Mediated NLRP3 Inflammasome Formation and Activation in Angiotensin II -Induced Hypertensive Mice: Role of Macrophage Digestion Dysfunction

Background/Aims: Angiotensin II (Ang II) is an octapeptide hormone that plays a significant role in mediating hypertension. Although hypertension is considered a chronic inflammatory disease, the molecular basis of the sterile inflammatory response involved in hypertension remains unclear. Methods: We investigated the role of macrophage NLRP3 inflammasomes in engulfing and digesting microbes, a key macrophage function, and in early onset of hypertension-associated macrophage injury using biochemical analyses, gene silencing, molecular biotechnology, immunofluorescence, and microbiology. Results: Ang II stimulation decreased nitric oxide (NO) release and macrophage digestion in cultured THP-1 cells and markedly increased NLRP3 inflammasome formation and activation. NO release and macrophage digestion were restored by NLRP3 inflammasome inhibition with isoliquiritigenin and gene silencing. This Ang II-induced upregulation of NLRP3 inflammasomes in macrophages was attributed to lysosomal damage and release of cathepsin B. Mechanistically, losartan, a nonpeptide Ang II receptor antagonist, decreased Ang II-induced NLRP3 inflammasome activation, lysosomal membrane permeability, lysosomal cathepsin B release, and macrophage digestion dysfunction. Similarly, Ang II-induced macrophage microbe digestion and NO production, which were blocked by ATI gene silencing. In addition, in vivo experiments showed that the bacteria scavenging function was clearly decreased in macrophages from Ang II-induced hypertensive mice. Conclusion: Angiotensin II enhances lysosomal membrane permeabilization and the consequent release of lysosomal cathepsin B, resulting in activation of the macrophage NLRP3 inflammasome. This may contribute to NO mediation of dysfunction in digesting microbes

2-D Shape Blending based on Visual Feature Decomposition

2-D polygon shape blending has been widely used in 2-D character animation, pattern matching, and geometric modeling. Previous algorithms mostly tend to use the polygon’s geometric elements such as edge, angle, area and skeleton, to associate the regions on the two shapes which look alike. However they ignore the visual features of two polygonal shapes. This paper presents a new 2-D polygonal shape blending method based on the correspondence of visual features. By decomposing the two shapes into sub-shape pairs which have similar visual features compatibly, the sub-shape in the source polygon can be smoothly transformed into the corresponding sub-shape in the destination polygon. Since the feature-decomposition vertices are introduced and our blending algorithm is so simple , the user can edit the visual correspondence of features flexibly and intuitively in real time. Experimental results show that the source shape can be transformed into the destination shape as prescribed by the user whilst keeping feature correspondence

Impact of Island Nuclear Power Project on the Spatial Distribution Pattern of Mariculture: A case Study of Niushan Island, China

Nuclear power generation is being promoted globally as a clean energy source and is one of China’s key tools for addressing carbon peaking and carbon neutrality. The Niushan Island of China was selected as the research area and conducted detailed seasonal surveys at sea to explore the spatial distribution pattern of marine aquaculture around nuclear power project and analyze the potential impact of island nuclear power project construction on major marine aquaculture species. The results showed that, the spatial distribution pattern of mariculture around the Sea Island Nuclear Power Project is closely related to the aquaculture environment and seasonality. The main mariculture activities include Porphyra cultivation, mudflat breeding and ponding aquaculture. The envelope area of suspended sediment greater than 10 mg/L is 13.0565 km2 during the construction of the project, which may have an impact on the Porphyra cultivation. The average half-moon tide 1.0°C temperature rise envelope is 31.30 km2 in summer and 2.64 km2 in winter for the 6×AP1400 nuclear power units. The temperature rise caused by human factors may have an impact on the breeding activities of “Jiluo Sanniu Marine Ranch”

Deployment of Mobile Air Sensing Network for Urban Air Pollution Monitoring in Hong Kong

Epidemiology studies have demonstrated an association between airborne pollutant and adverse effects [...