Effective adsorption of heavy metal ions in water by sulfhydryl modified nano titanium dioxide

Background: The monitoring and removal of heavy metal ions in wastewater will effectively improve the quality of water and promote the green and sustainable development of ecological environment. Using more efficient adsorption materials and more accurate detection means to treat heavy metal ions in water has always been a research focus and target of researchers.Method: A novel titania nanomaterial was modified with sulfhydryl group (nano TiO2-SH) for detection and adsorption of heavy metal ions in water, and accurately characterize the adsorption process using Surface-Enhanced Raman Spectroscopy (SERS) and other effective testing methods.Results: The maximum adsorption efficiency of nano TiO2-SH for the Hg2+, Cd2+, Pb2+ three heavy metal ions reached 98.3%, 98.4% and 98.4% respectively. And more importantly, after five cycles of adsorption and desorption, the adsorption efficiency of nano TiO2-SH for these three metal ions is still above 96%.Conclusion: These results proved the nano TiO2-SH adsorbent has great potential in practical water pollution purification

Neural Super-Resolution for Real-time Rendering with Radiance Demodulation

Rendering high-resolution images in real-time applications (e.g., video games, virtual reality) is time-consuming, thus super-resolution technology becomes more and more crucial in real-time rendering. However, it is still challenging to preserve sharp texture details, keep the temporal stability and avoid the ghosting artifacts in the real-time rendering super-resolution. To this end, we introduce radiance demodulation into real-time rendering super-resolution, separating the rendered image or radiance into a lighting component and a material component, due to the fact that the light component tends to be smoother than the rendered image and the high-resolution material component with detailed textures can be easily obtained. Therefore, we perform the super-resolution only on the lighting component and re-modulate with the high-resolution material component to obtain the final super-resolution image. In this way, the texture details can be preserved much better. Then, we propose a reliable warping module by explicitly pointing out the unreliable occluded regions with a motion mask to remove the ghosting artifacts. We further enhance the temporal stability by designing a frame-recurrent neural network to aggregate the previous and current frames, which better captures the spatial-temporal correlation between reconstructed frames. As a result, our method is able to produce temporally stable results in real-time rendering with high-quality details, even in the highly challenging 4 $\times$ 4 super-resolution scenarios

Multiple-bounce Smith Microfacet BRDFs using the Invariance Principle

Smith microfacet models are widely used in computer graphics to represent materials. Traditional microfacet models do not consider the multiple bounces on microgeometries, leading to visible energy missing, especially on rough surfaces. Later, as the equivalence between the microfacets and volume has been revealed, random walk solutions have been proposed to introduce multiple bounces, but at the cost of high variance. Recently, the position-free property has been introduced into the multiple-bounce model, resulting in much less noise, but also bias or a complex derivation. In this paper, we propose a simple way to derive the multiple-bounce Smith microfacet bidirectional reflectance distribution functions (BRDFs) using the invariance principle. At the core of our model is a shadowing-masking function for a path consisting of direction collections, rather than separated bounces. Our model ensures unbiasedness and can produce less noise compared to the previous work with equal time, thanks to the simple formulation. Furthermore, we also propose a novel probability density function (PDF) for BRDF multiple importance sampling, which has a better match with the multiple-bounce BRDFs, producing less noise than previous naive approximations

SVBRDF Recovery from a Single Image with Highlights Using a Pre‐trained Generative Adversarial Network

International audienceInput SVBRDF maps SVBRDF maps Render Render Figure 1: Our method generates high-quality and natural SVBRDF maps from a single input photograph with overexposed highlight regions, and provides vivid rendering. Our Fourier-based loss function separates the effects due to the specular highlight from those due to the material

Hematite Dodecahedron Crystals with High-index Facets Grown and Grafted on One Dimensional Structures for Efficient Photoelectrochemical H2 Generation

Fe2O3 polyhedrons are one of the most promising morphologies for photoelectrochemical water splitting. In spite of recent reports on the successful synthesis of various Fe2O3 polyhedrons, the fabrication of defined photoelectrodes by anchoring the polyhedron in a suitable configuration remains a great challenge. Herein, we introduce a synthetic strategy to prepare Fe2O3 dodecahedrons with high-index {112} facets directly anchored on a one dimensional Fe2O3 nanoflake ({110} facets) electrode. Key is that the Fe2O3 nanoflakes act as seeds for the initiation of the growth of dodecahedral nanocrystals from an iron nitrate solution. The initial single crystals consist of Fe3O4 with exposed {110} basal surfaces that then in a thermal step can be converted to hematite with {112} facets. The resulting single crystal (bi-crystal) hematite photoanode demonstrates a high efficiency for solar water splitting with an excellent photoresponse due to the synergistic effect of direct grafting of the light harvesting and reactive polyhedron and the 1D transport geometry. Under optimized conditions the hematite polyhedrons on nanoflake-structure show photocurrent densities of 2.4 mA cm-2 at 1.23 VRHE and 3.5 mA cm-2 at 1.5 VRHE under AM 1.5G simulated sunlight

Harpin-induced expression and transgenic overexpression of the phloem protein gene AtPP2-A1 in Arabidopsis repress phloem feeding of the green peach aphid Myzus persicae

<p>Abstract</p> <p>Background</p> <p>Treatment of plants with HrpN_Ea, a protein of harpin group produced by Gram-negative plant pathogenic bacteria, induces plant resistance to insect herbivores, including the green peach aphid <it>Myzus persicae</it>, a generalist phloem-feeding insect. Under attacks by phloem-feeding insects, plants defend themselves using the phloem-based defense mechanism, which is supposed to involve the phloem protein 2 (PP2), one of the most abundant proteins in the phloem sap. The purpose of this study was to obtain genetic evidence for the function of the <it>Arabidopsis thaliana </it>(Arabidopsis) PP2-encoding gene <it>AtPP2-A1 </it>in resistance to <it>M. persicae </it>when the plant was treated with HrpN_Eaand after the plant was transformed with <it>AtPP2-A1</it>.</p> <p>Results</p> <p>The electrical penetration graph technique was used to visualize the phloem-feeding activities of apterous agamic <it>M. persicae </it>females on leaves of Arabidopsis plants treated with HrpN_Eaand an inactive protein control, respectively. A repression of phloem feeding was induced by HrpN_Eain wild-type (WT) Arabidopsis but not in <it>atpp2-a1</it>/E/142, the plant mutant that had a defect in the <it>AtPP2-A1 </it>gene, the most HrpN_Ea-responsive of 30 <it>AtPP2 </it>genes. In WT rather than <it>atpp2-a1</it>/E/142, the deterrent effect of HrpN_Eatreatment on the phloem-feeding activity accompanied an enhancement of <it>AtPP2-A1 </it>expression. In PP2OETAt (<it>AtPP2-A1</it>-overexpression transgenic <it>Arabidopsis thaliana</it>) plants, abundant amounts of the <it>AtPP2-A1 </it>gene transcript were detected in different organs, including leaves, stems, calyces, and petals. All these organs had a deterrent effect on the phloem-feeding activity compared with the same organs of the transgenic control plant. When a large-scale aphid population was monitored for 24 hours, there was a significant decrease in the number of aphids that colonized leaves of HrpN_Ea-treated WT and PP2OETAt plants, respectively, compared with control plants.</p> <p>Conclusions</p> <p>The repression in phloem-feeding activities of <it>M. persicae </it>as a result of <it>AtPP2-A1 </it>overexpression, and as a deterrent effect of HrpN_Eatreatment in WT Arabidopsis rather than the <it>atpp2-a1</it>/E/142 mutant suggest that <it>AtPP2-A1 </it>plays a role in plant resistance to the insect, particularly at the phloem-feeding stage. The accompanied change of aphid population in leaf colonies suggests that the function of <it>AtPP2-A1 </it>is related to colonization of the plant.</p

Tenrec: A Large-scale Multipurpose Benchmark Dataset for Recommender Systems

Existing benchmark datasets for recommender systems (RS) either are created at a small scale or involve very limited forms of user feedback. RS models evaluated on such datasets often lack practical values for large-scale real-world applications. In this paper, we describe Tenrec, a novel and publicly available data collection for RS that records various user feedback from four different recommendation scenarios. To be specific, Tenrec has the following five characteristics: (1) it is large-scale, containing around 5 million users and 140 million interactions; (2) it has not only positive user feedback, but also true negative feedback (vs. one-class recommendation); (3) it contains overlapped users and items across four different scenarios; (4) it contains various types of user positive feedback, in forms of clicks, likes, shares, and follows, etc; (5) it contains additional features beyond the user IDs and item IDs. We verify Tenrec on ten diverse recommendation tasks by running several classical baseline models per task. Tenrec has the potential to become a useful benchmark dataset for a majority of popular recommendation tasks

Block copolymer/ferroelectric nanoparticle nanocomposites

Nanocomposites composed of diblock copolymer/ferroelectric nanoparticles were formed by selectively constraining ferroelectric nanoparticles (NPs) within diblock copolymer nanodomains via judicious surface modification of ferroelectric NPs. Ferroelectric barium titanate (BaTiO3) NPs with different sizes that are permanently capped with polystyrene chains (i.e., PS-functionalized BaTiO3NPs) were first synthesized by exploiting amphiphilic unimolecular star-like poly(acrylic acid)-block-polystyrene (PAA-b- PS) diblock copolymers as nanoreactors. Subsequently, PS-functionalized BaTiO3 NPs were preferentially sequestered within PS nanocylinders in the linear cylinder-forming polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) diblock copolymer upon mixing the BaTiO3 NPs with PS-b-PMMA. The use of PS-b-PMMA diblock copolymers, rather than traditional homopolymers, offers the opportunity for controlling the spatial organization of PS-functionalized BaTiO3 NPs in the PS-b-PMMA/BaTiO3 NP nanocomposites. Selective solvent vapor annealing was utilized to control the nanodomain orientation in the nanocomposites. Vertically oriented PS nanocylinders containing PS-functionalized BaTiO3 NPs were yielded after exposing the PS-b-PMMA/BaTiO3 NP nanocomposite thin film to acetone vapor, which is a selective solvent for PMMA block. The dielectric properties of nanocomposites in the microwave frequency range were investigated. The molecular weight of PS-b-PMMA and the size of BaTiO3 NPs were found to exert an apparent influence on the dielectric properties of the resulting nanocomposites

Constant-Cost Spatio-Angular Prefiltering of Glinty Appearance Using Tensor Decomposition

International audienceThe detailed glinty appearance from complex surface microstructures enhances the level of realism but is both - and time-consuming to render, especially when viewed from far away (large spatial coverage) and/or illuminated by area lights (large angular coverage). In this article, we formulate the glinty appearance rendering process as a spatio-angular range query problem of the Normal Distribution Functions (NDFs), and introduce an efficient spatio-angular prefiltering solution to it. We start by exhaustively precomputing all possible NDFs with differently sized positional coverages. Then we compress the precomputed data using tensor rank decomposition, which enables accurate and fast angular range queries. With our spatio-angular prefiltering scheme, we are able to solve both the storage and performance issues at the same time, leading to efficient rendering of glinty appearance with both constant storage and constant performance, regardless of the range of spatio-angular queries. Finally, we demonstrate that our method easily applies to practical rendering applications that were traditionally considered difficult. For example, efficient bidirectional reflection distribution function evaluation accurate NDF importance sampling, fast global illumination between glinty objects, high-frequency preserving rendering with environment lighting, and tile-based synthesis of glinty appearance

Sphere-forming cell subpopulations with cancer stem cell properties in human hepatoma cell lines

<p>Abstract</p> <p>Background</p> <p>Cancer stem cells (CSCs) are regarded as the cause of tumor formation and recurrence. The isolation and identification of CSCs could help to develop novel therapeutic strategies specifically targeting CSCs.</p> <p>Methods</p> <p>Human hepatoma cell lines were plated in stem cell conditioned culture system allowed for sphere forming. To evaluate the stemness characteristics of spheres, the self-renewal, proliferation, chemoresistance, tumorigenicity of the PLC/PRF/5 sphere-forming cells, and the expression levels of stem cell related proteins in the PLC/PRF/5 sphere-forming cells were assessed, comparing with the parental cells. The stem cell RT-PCR array was performed to further explore the biological properties of liver CSCs.</p> <p>Results</p> <p>The PLC/PRF/5, MHCC97H and HepG2 cells could form clonal nonadherent 3-D spheres and be serially passaged. The PLC/PRF/5 sphere-forming cells possessed a key criteria that define CSCs: persistent self-renewal, extensive proliferation, drug resistance, overexpression of liver CSCs related proteins (Oct3/4, OV6, EpCAM, CD133 and CD44). Even 500 sphere-forming cells were able to form tumors in NOD/SCID mice, and the tumor initiating capability was not decreased when spheres were passaged. Besides, downstream proteins DTX1 and Ep300 of the CSL (CBF1 in humans, Suppressor of hairless in Drosophila and LAG1 in C. elegans) -independent Notch signaling pathway were highly expressed in the spheres, and a gamma-secretase inhibitor MRK003 could significantly inhibit the sphere formation ability.</p> <p>Conclusions</p> <p>Nonadherent tumor spheres from hepatoma cell lines cultured in stem cell conditioned medium possess liver CSC properties, and the CSL-independent Notch signaling pathway may play a role in liver CSCs.</p