Dense Mapping From an Accurate Tracking SLAM

In recent years, reconstructing a sparse map from a simultaneous localization and mapping(SLAM) system on a conventional CPU has undergone remarkable progress. However,obtaining a dense map from the system often requires a highperformance GPU to accelerate computation. This paper proposes a dense mapping approach which can remove outliers and obtain a clean 3D model using a CPU in real-time. The dense mapping approach processes keyframes and establishes data association by using multi-threading technology. The outliers are removed by changing detections of associated vertices between keyframes. The implicit surface data of inliers is represented by a truncated signed distance function and fused with an adaptive weight. A global hash table and a local hash table are used to store and retrieve surface data for data-reuse. Experiment results show that the proposed approach can precisely remove the outliers in scene and obtain a dense 3D map with a better visual effect in real-time.

Copyright Rules for UGC Platforms: From the Safe Harbor Rule to a Levy Scheme

The safe harbor rule was introduced to exempt Internet service providers(ISPs)from liability for copyright infringement committed by ISP users.Nevertheless,the safe harbor rule was crafted for ISPs that provide passive,content-neutral service to distribute copyrighted works.Therefore,the safe harbor rule is difficult to accommodate UGC(user-generated-content)platforms due to their active role in facilitating the distribution and even the creation of copyrighted works.The uncertainty of UGC platforms’liability has led copyright owners to directly target individual UGC creators.In order to unleash the creativity of users without harming the interests of copyright owners,a levy scheme should be introduced.Under the levy scheme,users are allowed to freely use copyrighted works to create UGC for non-commercial purpose.UGC platforms are required to remunerate the copyright owners of the copyrighted works used in the UGC posted on the platforms based on the popularity of the UGC.

Introducing a Levy Scheme to Online Educational Use of Copyrighted Works

It is common for teachers to use others'copyrighted works for the purpose of teaching.The current copyright law in many nations only exempts educational use in the context of offline classroom teaching.The use of others’copyrighted material in online teaching may still constitute copyright infringement.To protect teachers from the chilling effect of copyright infringement,to safeguard the public's freedom to obtain knowledge,and to ensure the commensurability of the profits and responsibilities of online teaching platforms,this paper proposes a levy scheme for online teaching.Under the levy scheme,teachers are free to use others’published work for the purpose of online teaching,provided that such use does not conflict with a normal exploitation of the work and does not unreasonably prejudice the legitimate interest of the copyright owner.Online teaching platforms should remunerate the copyright owner of the work used in the platform according to the number of participants of the course that uses such work.

Compositional characteristics and toxicological responses of human lung epithelial cells to inhalable particles (PM_(10)) from ten typical biomass fuel combustions

As the primary component of haze,atmospheric inhalable particulate matters(PMio)are highly detri-mental to human health.Biomass combustion is one of China's most pivotal sources to aerosols pollution,inducing non-negligible emissions and uncertain risks.PMio samples directly from 10 representative biomass fuel combustion sources(2 groups covering the reality widely:straws of rice,wheat,corn,corncob,soybean,peanut,rape,sesame;and branches of pine,peach)were collected using the dilution channel sampler and analyzed for chemical compositions and in vitro cytotoxicity to human lung epithelial cell lines A549.The components of PMio are dominated by organic carbon(OC),followed by Water-soluble K+and Cl,and rich in metals Fe,Zn,Cr,and Ni.Generally,PMio emitted from biomass fuel combustions can weaken the antioxidant capacity of cells,and straws emissions,especially rape and peanut straws,show stronger ability to further induce oxidative stress and inflammatory damage than fuelwoods,owing to the key toxic roles of Cr,Ni,and Co.Therefore,reducing the specific source emis--sions of PMio from crop straw combustions rich in heavy metals could be an effective oriented strategy to improve environmental air quality and control aerosols pollution precisely for protecting public health.

Biosynthesis and Regulation of Salicylic Acid and N-Hydroxypipecolic Acid in Plant Immunity

Salicylic acid(SA)has long been known to be essential for basal defense and systemic acquired resistance(SAR).N-Hydroxypipecolic acid(NHP),a recently discovered plant metabolite,also plays a key role in SAR and to a lesser extent in basal resistance.Following pathogen infection,levels of both compounds are dramatically increased.Analysis of SA-or SAR-deficient mutants has uncovered how SA and NHP are biosynthesized.The completion of the SA and NHP biosynthetic pathways in Arabidopsis allowed better understanding of how they are regulated.In this review,we discuss recent progress on SA and NHP biosynthesis and their regulation in plant immunity.

Arabidopsis CALMODULIN-BINDING PROTEIN 60b plays dual roles in plant immunity

Arabidopsis SYSTEMIC ACQUIRED RESISTANCE DEFICIENT 1(SARD1)and CALMODULIN-BINDING PROTEIN 60g(CBP60g)are two master transcription factors that regulate many defense-related genes in plant immunity.They are required for immunity downstream of the receptor-like protein SUPPRESSOR OF NPR1-1,CONSTITUTIVE 2(SNC2).Constitutive defense responses in the gain-of-function autoimmune snc2-1D mutant are modestly affected in either sard1 or cbp60g single mutants but completely suppressed in the sard1 cbp60g double mutant.Here we report that CBP60b,another member of the CBP60 family,also functions as a positive regulator of SNC2-mediated immunity.Loss-of-function mutations of CBP60b suppress the constitutive expression of SARD1 and enhanced disease resistance in cbp60g-1 snc2-1D,whereas overexpression of CBP60b leads to elevated SARD1 expression and constitutive defense responses.In addition,transient expression of CBP60b in Nicotiana benthamiana activates the expression of the pSARD1::luciferase reporter gene.Chromatin immunoprecipitation assays further showed that CBP60b is recruited to the promoter region of SARD1,suggesting that it directly regulates SARD1 expression.Interestingly,knocking out CBP60b in the wild-type background leads to ENHANCED DISEASE SUSCEPTIBILITY 1(EDS1)-dependent autoimmunity,suggesting that CBP60b is required for the expression of a guardee/decoy or a negative regulator of immunity mediated by receptors carrying an N-terminal Toll-interleukin-1 receptor-like domain.

Bacterial Vector-Borne Plant Diseases:Unanswered Questions and Future Directions

Vector-borne plant diseases have significant ecological and economic impacts,affecting farm profitability and forest composition throughout the world.Bacterial vector-borne pathogens have evolved sophisticated strategies to interact with their hemipteran insect vectors and plant hosts.These pathogens reside in plant vascular tissue,and their study represents an excellent opportunity to uncover novel biological mechanisms regulating intracellular pathogenesis and to contribute to the control of some of the world's most invasive emerging diseases.In this perspective,we highlight recent advances and major unanswered questions in the realm of bacterial vector-borne disease,focusing on liberibacters,phytoplasmas,spiroplasmas,and Xylella fastidiosa.

Differences in postembryonic dorsal fin development resulted in phenotypic divergence in two goldfish strains, Red Cap Oranda and Ranchu

Goldfish(Carassius auratus auratus)are important ornamental fish that have experienced extreme anthropogenic selection and exhibit diverse phenotypes.Loss of the dorsal fin is a key characteristic that distinguishes the Egg-goldfish from the Wen-goldfish.However,the mechanisms underlying the divergence in dorsal fin development are still unknown between the Egg-goldfish and the Wen-goldfish.In this study,we sought to unravel the postembryonic developmental processes of two goldfish strains,Red Cap Oranda,a representative of the Wen-goldfish,and Ranchu,a representative of the Egg-goldfish.We examined the developmental morphology of the dorsal fin in five-month-old goldfish larvae using both Alcian blue-alizarin red staining and X-ray photography.We showed that the developmental processes of the dorsal fin fold were different in Ranchu compared to Red Cap Oranda,despite similarity in their general developmental processes.We categorized the postembryonic development of Ranchu larvae into four types based on the number of the initial residual dorsal fin fold appearing at protruding-mouth stage.The number,size and position of the initial residual dorsal fin fold appeared at hatching affected and eventually determined the phenotypic variations in dorsal fin defects in Ranchu.In addition,we genotyped the eomesa gene to determine whether it would be a candidate gene responsible for the loss of the dorsal fin in Ranchu.The eomesa CDS sequence exhibited no nonsense mutation in Ranchu.In summary,the absence of the dorsal fin fold during postembryonic development eventually resulted in the loss of the dorsal fin in Ranchu.Further investigation is required to determine whether other genes and developmental pathways play important roles in the loss of the dorsal fin in Ranchu.

A MIXED FINITE ELEMENT METHOD FOR MULTI-CAVITY COM PUTATION IN INCOMPRESSIBLE NONLINEAR ELASTICITY

A mixed finite element method combining an iso-parametric Q 2-P 1 element and an isoparametric P^-Pi element is developed for the computation of multiple cavities in incompressible nonlinear elasticity. The method is analytically proved to be locking-free and convergent, and it is also shown to be numerically accurate and efficient by numerical experiments. Furthermore, the newly developed accurate method enables us to find an interesting new bifurcation phenomenon in multi-cavity growth.

A θ-L APPROACH FOR SOLVING SOLID-STATE DEWETTING PROBLEMS

We propose a θ-L approach for solving a sharp-interface model about simulating solid-state dewetting of thin films with isotropic/weakly anisotropic surface energies.The sharp-interface model is governed by surface diffusion and contact line migration.For solving the model,traditional numerical methods usually suffer from the severe stability constraint and/or the mesh distribution trouble.In the θ-L approach,we introduce a useful tangential velocity along the evolving interface and utilize a new set of variables(i.e.,the tangential angle 6 and the total length L of the interface curve),so that it not only could reduce the stiffness resulted from the surface tension,but also could ensure the mesh equidistri-bution property during the evolution.Furthermore,it can achieve second-order accuracy when implemented by a semi-implicit linear finite element method.Numerical results are reported to demonstrate that the proposed θ-L approach is efficient and accurate.