Human Performance Modeling and Rendering via Neural Animated Mesh

We have recently seen tremendous progress in the neural advances for photo-real human modeling and rendering. However, it's still challenging to integrate them into an existing mesh-based pipeline for downstream applications. In this paper, we present a comprehensive neural approach for high-quality reconstruction, compression, and rendering of human performances from dense multi-view videos. Our core intuition is to bridge the traditional animated mesh workflow with a new class of highly efficient neural techniques. We first introduce a neural surface reconstructor for high-quality surface generation in minutes. It marries the implicit volumetric rendering of the truncated signed distance field (TSDF) with multi-resolution hash encoding. We further propose a hybrid neural tracker to generate animated meshes, which combines explicit non-rigid tracking with implicit dynamic deformation in a self-supervised framework. The former provides the coarse warping back into the canonical space, while the latter implicit one further predicts the displacements using the 4D hash encoding as in our reconstructor. Then, we discuss the rendering schemes using the obtained animated meshes, ranging from dynamic texturing to lumigraph rendering under various bandwidth settings. To strike an intricate balance between quality and bandwidth, we propose a hierarchical solution by first rendering 6 virtual views covering the performer and then conducting occlusion-aware neural texture blending. We demonstrate the efficacy of our approach in a variety of mesh-based applications and photo-realistic free-view experiences on various platforms, i.e., inserting virtual human performances into real environments through mobile AR or immersively watching talent shows with VR headsets.Comment: 18 pages, 17 figure

Coupling calculation and analysis of three-dimensional temperature and fluid field for high-power high-speed permanent magnet machine

© The Institution of Engineering and Technology 2019. In order to accurately estimate the temperature rise for high-power high-speed permanent magnet machines (HSPMMs), a novel temperature calculation method considering the non-linear variation of material properties with temperature is proposed based on multi-physics co-simulation analysis. According to the theory of computational fluid dynamics and heat transfer, the computation model of fluid-solid-heat coupling heat transfer is established, and the coupled field is calculated using finite volume method with fundamental assumptions and corresponding boundary conditions. With the influences from temperature gradient and water flow rate considered, the heat transfer coefficients of water pipe surfaces are obtained by the application of the inverse iteration method. Thus, HSPMM temperature and fluid field can be simulated numerically by the finite volume methods, while the spatial temperature distributions for the machine main components are analysed in this study. The 1.12â€.MW, 18,000â€.rpm HSPMM is prototyped with experiments conducted on it, while the test data are then compared with the calculated results, which validate the correctness of the solution method of the coupled field

The paleoclimatic footprint in the soil carbon stock of the Tibetan permafrost region

Data and code availability The authors declare that the majority of the data supporting the findings of this study are available through the links given in the paper. The unpublished data are available from the corresponding author upon request. The new estimate of Tibetan soil carbon stock and R code are available in a persistent repository (https://figshare.com/s/4374f28d880f366eff6d). Acknowledgements This study was supported by the Strategic Priority Research Program (A) of the Chinese Academy of Sciences (XDA20050101), the National Natural Science Foundation of China (41871104), Key Research and Development Programs for Global Change and Adaptation (2017YFA0603604), International Partnership Program of the Chinese Academy of Sciences (131C11KYSB20160061) and the Thousand Youth Talents Plan project in China. Jinzhi Ding acknowledges the General (2017M620922) and the Special Grade (2018T110144) of the Financial Grant from the China Postdoctoral Science Foundation.Peer reviewedPublisher PD

The Changes in Maternal Mortality in 1000 Counties in Mid-Western China by a Government-Initiated Intervention

BACKGROUND: Since 2000, the Chinese government has implemented an intervention program to reduce maternal mortality and eliminate neonatal tetanus in accordance with the Millennium Development Goals 5. To assess the effectiveness of this intervention program, we analyzed the level, trend and reasons defining the maternal mortality ratio (MMR) in the 1,000 priority counties before and after implementation of the intervention between 1999 and 2007. METHODOLOGY/PRINCIPAL FINDINGS: The data was obtained from the National Maternal and Child Health Routine Reporting System. The intervention included providing basic and emergency obstetric equipment and supplies to local medical hospitals, and also included providing professional training to local obstetric doctors, development of obstetric emergency centers and "green channel" express referral networks, reducing or waiving the cost of hospital delivery, and conducting community health education. Based on the initiation time of the intervention and the level of poverty, 1,000 counties, containing a total population of 300 million, were categorized into three groups. MMR significantly decreased by about 50%, with an average reduction rate of 9.24%, 16.06%, and 18.61% per year in the three county groups, respectively. The hospital delivery rate significantly increased. Obstetric hemorrhage was the leading cause of maternal deaths and significantly declined, with an average decrease in the MMR of 11.25%, 18.03%, and 24.90% per year, respectively. The magnitude of the MMR, the average reduction rate of the MMR, and the occurrence of the leading causes of death were closely associated with the percentage of poverty. CONCLUSIONS/SIGNIFICANCE: The intervention program implemented by the Chinese government has significantly reduced the MMR in mid-western China, suggesting that well-targeted interventions could be an efficient strategy to reducing MMR in resource-poor areas. Reduction of the MMR not only depends on conducting proven interventions, but also relies on economic development in rural areas with a high burden of maternal death

The number and microlocalization of tumor-associated immune cells are associated with patient's survival time in non-small cell lung cancer

<p>Abstract</p> <p>Background</p> <p>Tumor microenvironment is composed of tumor cells, fibroblasts, endothelial cells, and infiltrating immune cells. Tumor-associated immune cells may inhibit or promote tumor growth and progression. This study was conducted to determine whether the number and microlocalization of macrophages, mature dendritic cells and cytotoxic T cells in non-small cell lung cancer are associated with patient's survival time.</p> <p>Methods</p> <p>Ninety-nine patients with non-small cell lung cancer (NSCLC) were included in this retrospective study. Paraffin-embedded NSCLC specimens and their clinicopathological data including up to 8-year follow-up information were used. Immunohistochemical staining for CD68 (marker for macrophages), CD83 (marker for mature dendritic cells), and CD8 (marker for cytotoxic T cells) was performed and evaluated in a blinded fashion. The numbers of immune cells in tumor islets and stroma, tumor islets, or tumor stroma were counted under a microscope. Correlation of the cell numbers and patient's survival time was analyzed using the Statistical Package for the Social Sciences (version 13.0).</p> <p>Results</p> <p>The numbers of macrophages, mature dendritic cells and cytotoxic T cells were significantly more in the tumor stroma than in the tumor islets. The number of macrophages in the tumor islets was positively associated with patient's survival time, whereas the number of macrophages in the tumor stroma was negatively associated with patient's survival time in both univariate and multivariate analyses. The number of mature dendritic cells in the tumor islets and stroma, tumor islets only, or tumor stroma only was positively associated with patient's survival time in a univariate analysis but not in a multivariate analysis. The number of cytotoxic T cells in the tumor islets and stroma was positively associated with patient's survival time in a univariate analysis but not in a multivariate analysis. The number of cytotoxic T cells in the tumor islets only or stroma only was not associated with patient's survival time.</p> <p>Conclusions</p> <p>The number of macrophages in the tumor islets or stroma is an independent predictor of survival time in NSCLC patients. Counting macrophages in the tumor islets or stroma is more useful in predicting patient's survival time than counting mature dendritic cells or cytotoxic T cells.</p

Preventable maternal mortality: Geographic/rural-urban differences and associated factors from the population-based maternal mortality surveillance system in China

<p>Abstract</p> <p>Background</p> <p>Most maternal deaths in developing countries can be prevented. China is among the 13 countries with the most maternal deaths; however, there has been a marked decrease in the maternal mortality ratio (MMR) over the last 3 decades. China's reduction in the MMR has contributed significantly to the global decline of the MMR. This study examined the geographic and rural-urban differences, time trends and related factors in preventable maternal deaths in China during 1996-2005, with the aim of providing reliable evidence for effective interventions.</p> <p>Methods</p> <p>Data were retrieved from the population-based maternal mortality surveillance system in China. Each death was reviewed by three committees to determine whether it was avoidable. The preventable maternal mortality ratio (PMMR), the ratios of PMMR (risk ratio, RR) and 95% confidence intervals (CI) were used to analyze regional disparities (coastal, inland and remote regions) and rural-urban variations. Time trends in the MMR, along with underlying causes and associated factors of death, were also analysed.</p> <p>Results</p> <p>Overall, 86.1% of maternal mortality was preventable. The RR of preventable maternal mortality adjusted by region was 2.79 (95% CI 2.42-3.21) and 2.38 (95% CI: 2.01-2.81) in rural areas compared to urban areas during the 1996-2000 and 2001-2005 periods, respectively. Meanwhile, the RR was the highest in remote areas, which was 4.80(95%CI: 4.10-5.61) and 4.74(95%CI: 3.86-5.83) times as much as that of coastal areas. Obstetric haemorrhage accounted for over 50% of preventable deaths during the 2001-2005 period. Insufficient information about pregnancy among women in remote areas and out-of-date knowledge and skills of health professionals and substandard obstetric services in coastal regions were the factors frequently associated with MMR.</p> <p>Conclusions</p> <p>Preventable maternal mortality and the distribution of its associated factors in China revealed obvious regional differences. The PMMR was higher in underdeveloped regions. In future interventions in remote and inland areas, more emphasis should be placed on improving women's ability to utilize healthcare services, enhancing the service capability of health institutions, and increasing the accessibility of obstetric services. These approaches will effectively lower PMMR in those regions and narrow the gap among the different regions.</p

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Assessing Soil Quality for Sustainable Cropland Management Based on Factor Analysis and Fuzzy Sets: A Case Study in the Lhasa River Valley, Tibetan Plateau

Ecologically fragile cropland soils and intensive agricultural production are characteristic of the valley area of the Tibetan Plateau. A systematic assessment of soil quality is necessary and important for improving sustainable cropland management in this area. This study aims to establish a minimum data set (MDS) for soil quality assessment and generate an integrated soil quality index for sustainable cropland management in the Tibetan Plateau. Soil samples were collected from the 0&ndash;20 cm depths of agricultural land in the middle and lower reaches of the Lhasa River. These samples were analyzed by routine laboratory methods. Significant differences were identified via statistical test between different soil types and land use types for each soil property. Principal component analysis was used to define a MDS of indicators that determine soil quality. Consequently, effective porosity, pH, total organic C, total N, available P, and catalase were identified as the final MDS. The soil quality index was obtained by the fuzzy-set membership function and the linear weighted additive method. The soil quality index differed significantly between the soil types and land use types. The soil quality can be ranked based on their indices in the following order: 1. Grain land with meadow soils, 2. Grain land with steppe soils, 3. Greenhouse vegetable land with fluvo-aquic soils, 4. Grain land with fluvo-aquic soils. The soils with higher soil quality indices exhibited better soil structure, higher nutrient contents, and superior resistance to water and nutrient loss. While the intensive tillage practices associated with vegetable production could reduce the values for effective porosity, pH and catalase, the application of appropriate fertilizers increased the values for total organic C, total N and available P. Therefore, the MDS method is an effective and useful tool to identify the key soil properties for assessing soil quality, and provides guidance on adaptive cropland management to a variety of soil types and land use types

Partitioning of Cotton Field Evapotranspiration under Mulched Drip Irrigation Based on a Dual Crop Coefficient Model

Estimation of field crop evapotranspiration (ETc) and its partitioning into evaporation and transpiration, are of great importance in hydrological modeling and agricultural water management. In this study, we used a dual crop coefficient model SIMDualKc to estimate the actual crop evapotranspiration (ETc act ) and the basal crop coefficients over a cotton field in Northwestern China. A two-year field experiment was implemented in the cotton field under mulched drip irrigation. The simulated ETc act is consistent with observed ETc act as derived based on the eddy covariance system in the field. Basal crop coefficients of cotton for the initial, mid-season, and end-season are 0.20, 0.90, and 0.50, respectively. The transpiration components of ETc  act are 96% (77%) and 94% (74%) in 2012 and 2013 with (without) plastic mulch, respectively. The impact of plastic mulch cover on soil evaporation is significant during drip irrigation ranging from crop development stage to mid-season stage. The extent of the impact depends on the variation of soil moisture, available energy of the soil surface, and the growth of the cotton leaves. Our results show that the SIMDualKc is capable of providing accurate estimation of ETc act for cotton field under mulched drip irrigation, and could be used as a valuable tool to establish irrigation schedule for cotton fields in arid regions as Northwestern China