基于神经辐射场结构模糊优化的三维重建

少视图三维重建仅需要较少的视图来恢复物体的三维几何形状或场景。但由于少视图存在不同视角上的覆盖不足、缺乏足够的信息来准确还原三维场景的问题,会导致重建结果的不准确或者模糊,尤其针对具有复杂几何结构的场景难以捕获到场景的结构信息。本文提出了一种基于神经辐射场的框架,利用准确成本代价体关联前景和后景深度信息解决结构模糊的问题。首先,利用金字塔网络提取前景和后景的局部特征,加强对场景细节的捕捉,引入了Self-attention机制,以确保在特征提取过程中关注关键区域。然后,通过自适应感受野模块实现特征尺度的平滑传递,以此来构建一个准确的特征代价体。最后,引入随机结构相似性损失,利用局部区域像素作为整体监督替代像素逐点监督,以更全面地捕捉场景中的结构信息。在DTU数据集、LLFF数据集以及NeRF数据集上的PSNR分别提升了0.48 Db、0.1 Db、0.47 Db,实验数据表明,本文方法能有效解决少视图三维重建中信息不足导致的结构模糊问题。

Transcriptional regulation of MdPIN7 by MdARF19 during gravityinduced formation of adventitious root GSA in self-rooted apple stock

Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the considerable difference in the development of a gravitropic set-point angle(GSA)between self-rooted apple stock and seedling rootstock.Therefore,it is crucial to study the molecular mechanism of adventitious root GSA in self-rooted apple stock for breeding self-rooted and deep-rooted apple rootstock cultivars.An apple auxin response factor MdARF19 functioned to establish the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.MdARF19 bound directly to the MdPIN7 promoter,activating its transcriptional expression and thus regulating the formation of the adventitious root GSA in 12-2 self-rooted apple stock.However,MdARF19 influenced the expression of auxin efflux carriers(MdPIN3 and MdPIN10)and the establishment of adventitious root GSA of self-rooted apple stock in response to gravity signals by direct activation of MdFLP.Our findings provide new information on the transcriptional regulation of MdPIN7 by auxin response factor MdARF19 in the regulation of the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.

Isolation of Trichoderma virens 6PS-2 and its effects on Fusarium proliferatum f. sp. Malus domestica MR5 related to apple replant disease in China

Apple replant disease(ARD) is primarily caused by biotic factors that seriously inhibits the development of apple industry. Therefore, the use of biological control measures to inhibit the main pathogens(such as Fusarium spp.) that cause ARD is of great significance to the sustainable development of the apple industry. Trichoderma virens 6PS-2, which exhibited antagonism toward a variety of pathogens, was screened from the rhizosphere soils of healthy apple trees(Malus robusta) in different replanted orchards in the Yantai and Zibo Cities, Shandong Province, China. Its fermentation extract inhibited the growth of pathogenic Fusarium proliferatum f. sp. Malus domestica MR5, which was proportional to the concentration. These substances also increased the hairy root volume and growth of Arabidopsis thaliana lateral roots. The phenotype of Malus hupehensis seedlings and microbial community structure in rhizosphere soils in greenhouse experiment using Highthroughput sequencing were analyzed, and the field experiment with grafted apple trees were used for further verification. Compared with the application of potato dextrose broth(PDB) medium, application of 6PS-2 spore suspension directly to replanted soils could improve the growth of M. hupehensis seedlings as well as the elongation of grafted apple trees. Concomitant decreases in the gene copy number of Fusarium and increases in the culturable bacteria/fungi were also observed in the greenhouse and field experiments. The abundance of Trichoderma,Bacillus, and Streptomyces increased significantly, but that of Fusarium, Pseudarthrobacter, and Humicola decreased. The content of esters, phenols,furans, and amino acids in root exudates of M. hupehensis seedlings increased, which significantly inhibited the multiplication of Fusarium, but was positively correlated with Bacillus and Trichoderma. In summary, T. virens 6PS-2 not only directly inhibits the activity of pathogenic Fusarium but also secrets secondary metabolites with antifungal and growth-promoting potential. In addition, 6PS-2 spore suspension can also promote the growth of plants to a certain extent, and change the soil microbial community structure of rhizosphere soils. It is believed that T. virens 6PS-2 has the potential for the alleviation of apple replant disease(ARD) in China.

p53 codon 72基因多态性与中国女性乳腺癌发生风险关系的系统评价与Meta分析

目的探讨p53 codon 72基因多态性与中国女性乳腺癌发生风险的关系。方法计算机检索PubMed、Embase、Web of Science、中国知网、万方数据库,收集有关p53 codon 72基因多态性与乳腺癌发生风险的相关研究,检索时限为建库至2021年3月31日。采用Stata 16.0、RevMan 5.4软件进行系统评价和Meta分析。结果共纳入13项研究,包括5411例乳腺癌患者和5758例医院非癌患者或社区健康人群。Meta分析结果显示,纯合子模型[PP vs.RR:OR=1.16,95%CI(0.93,1.46),P=0.200]、隐性模型[PP vs.RR+PR:OR=1.09,95%CI(0.91,1.32),P=0.340]及显性模型[PP+PR vs.RR:OR=1.13,95%CI(0.97,1.30),P=0.120]显示p53 codon 72基因多态性与中国女性乳腺癌发生风险无关,而杂合子模型[PR vs.RR:OR=1.15,95%CI(1.05,1.26),P=0.002]则显示有关。亚组分析进一步发现,样本量较大的研究更易得出p53 codon 72基因多态性与中国女性乳腺癌发生风险相关的结论。此外,在杂合子模型中,对照组为社区健康人群或基因型频率符合Hardy-Weinberg平衡时,也易于得出类似结论。漏斗图和Egger's检验均提示无发表偏倚。敏感性分析显示,除显性模型外,其余模型分析均显示单个研究不改变Meta分析结果。结论杂合子模型分析显示p53 codon 72基因多态性可能与中国女性乳腺癌发生风险有关,未来需纳入更多高质量、大样本研究进行验证。

Effects of Soil Texture on the Growth of Young Apple Trees and Soil Microbial Community Structure Under Replanted Conditions

A two-year field experiment was carried out in order to study the occurrence degree and mechanism of apple replant disease(ARD)in the apple orchards with different soil textures.So we can adopt appropriate controlmeasures according to the severity of ARD.Healthy two-year-old seedlings with consistent growth were selected,of which the root stock was T337 and the scion was Yanfu 3.There were significant differences in biomass between methyl bromide fumigation and replanted treatments,and the difference was the largest in clay loam,followed by sandy loam,and loam,which verified ARD in clay loam was most serious,followed by sandy loam and loam.Based on high-throughput sequencing of fungi in soil samples,fungal richness and diversity were the highest in clay loam,followed by sandy loam,and loam.The relative abundance of Fusarium in SX,SL,FX,FL,WX and WL was 7.33%,19.32%,2.70%,4.24%,10.71%and 23.87%,respectively.Based on Real-time quantitative analysis,there were significant differences in the number of Fusarium oxysporum and Fusarium solani between methyl bromide fumigation and replanted treatments,i.e.,clay loam>sandy loam>loam.Fusarium was the main pathogen causing ARD.This shows that ARD is the most serious under replanted clay loam condition.High-throughput sequencing technology was used to prove the difference in Fusarium was one of the important reasons for ARD under different soil textures.This technology provides a new idea for the prevention and control of ARD.

Rearrangement on surface structures by boride to enhanced cycle stability for LiNi0.80Co0.15Al0.05O2 cathode in lithium ion batteries

The side reaction between the active material and liquid-electrolyte cause structural damage and particle pulverization is one of the important factors leading to the capacity decay of LiNi0.80Co0.15Al0.05O2(NCA)materials in Li ion batteries(LIBs).Surface modification is an effective strategy for NCA cathodes,which could alleviate the degradation associated with surface processes.Herein,a surface structure rearrangement of NCA cathode secondary particles was reported by in-situ forming a solid electrolyte LiBO2.The LiBO2 is beneficial for alleviating the stress during charge/discharge process,thereby slowing down the rate of cracks formation in the secondary particles,which facilitates the Li+de-intercalation as well as prevents penetration of the liquid-electrolyte into the interior of the particles.As a result,the surface structure rearrangement NCA(RS-NCA)delivers a high discharge capacity of 202.5 m Ah g^-1 at 0.1 C,and exhibits excellent cycle stability with discharge capacity retaining 148 m Ah g^-1 after 200 cycles at 2 C.This surface structure rearrangement approach provides a new viewpoint in designing high-performance high-voltage LIBs.

Activation of disease resistance against Botryosphaeria dothidea by downregulating the expression of MdSYP121 in apple

In plants,the vesicle fusion process plays a vital role in pathogen defence.However,the importance of the vesicle fusion process in apple ring rot has not been studied.Here,we isolated and characterised the apple syntaxin gene MdSYP121.Silencing the MdSYP121 gene in transgenic apple calli increased tolerance to Botryosphaeria dothidea infection;this increased tolerance was correlated with salicylic acid(SA)synthesis-related and signalling-related gene transcription.In contrast,overexpressing MdSYP121 in apple calli resulted in the opposite phenotypes.In addition,the results of RNA sequencing(RNA-Seq)and quantitative real-time PCR(qRT-PCR)assays suggested that MdSYP121 plays an important role in responses to oxidation–reduction reactions.Silencing MdSYP121 in apple calli enhanced the expression levels of reactive oxygen species(ROS)-related genes and the activity of ROS-related enzymes.The enhanced defence response status in MdSYP121-RNAi lines suggests that syntaxins are involved in the defence response to B.dothidea.More importantly,we showed that MdSYP121 forms a soluble N-ethylmaleimide-sensitive factor attachment protein receptor(SNARE)complex with MdSNAP33,and the complex may participate in regulating resistance to B.dothidea.In conclusion,by regulating the interaction of SA pathway and oxidation–reduction process,MdSYP121 can influence the pathogen infection process in apple.

基于高通量测序分析晚期肺癌患者肺部微生物多样性

背景与目的肺部微生物组与肺部疾病的发生密切相关,微生物可从多方面促进肿瘤的发生与发展。既往研究证实肺癌患者肺部微生物组较健康人发生了变化,但关于不同类型肺癌患者中肺部微生物组的微生物组成尚未明确。本研究旨在探讨不同组织学类型肺癌间的微生物组相关性及差异性。方法采用Illumina HiSeq高通量测序技术对晚期肺癌患者痰样本进行细菌V3-V4区的16S rDNA测序及生物信息学分析。结果经物种分类分析发现肺癌患者痰样本中以链球菌属、奈瑟氏菌属、普雷沃氏菌属为主。腺癌(adenocarcinoma,AD)组以链球菌属及奈瑟氏菌属为主,小细胞肺癌(small cell lung cancer,SCLC)组以奈瑟氏菌属为主,鳞状细胞癌(squamous cell carcinoma,SCC)组以链球菌属为主,混合型小细胞肺癌(combined small cell lung cancer,C-SCLC)组以链球菌属为主。结论不同组织学类型肺癌的肺部细菌微生物组结构及组成存在差异性,不同组织学类型肺癌间优势菌群有所不同,本研究丰富了肺癌肺部细菌微生物组学数据。

Topic Evolution and Emerging Topic Analysis Based on Open Source Software

Purpose:We present an analytical,open source and flexible natural language processing and text mining method for topic evolution,emerging topic detection and research trend forecasting for all kinds of data-tagged text.Design/methodology/approach:We make full use of the functions provided by the open source VOSviewer and Microsoft Office,including a thesaurus for data clean-up and a LOOKUP function for comparative analysis.Findings:Through application and verification in the domain of perovskite solar cells research,this method proves to be effective.Research limitations:A certain amount of manual data processing and a specific research domain background are required for better,more illustrative analysis results.Adequate time for analysis is also necessary.Practical implications:We try to set up an easy,useful,and flexible interdisciplinary text analyzing procedure for researchers,especially those without solid computer programming skills or who cannot easily access complex software.This procedure can also serve as a wonderful example for teaching information literacy.Originality/value:This text analysis approach has not been reported before.

The effects of crop rotation combinations on the soil quality of old apple orchard

This study investigated the effects of six crop rotation combinations on the soil quality of old apple orchard and seedling growth of Malus hupehensis Rehd.(apple rootstock) under pot conditions. The inhibitory effects of crops such as Allium fistulosum, Brassica juncea, and Triticum aestivum on four species of Fusarium were observed and compared in six treatments. These were continuous cropping(CK), fumigation with the methyl bromide(FM), rotating A. fistulosum only(R1), rotating A. fistulosum and T. aestivum(R2), rotating A. fistulosum, B. juncea, and T. aestivum(R3), and fallow(FC) in a year. The results showed that the biomass of Malus hupehensis Rehd. seedlings increased significantly. The root length increased and the root architecture was optimized. The respiration rate of the root system was increased by about 1 time after rotation. The treatments of R1, R2, R3, and FC increased bacterial count by 232.17%, 96.04%, 316.21%, and 60.02%, respectively. However, the fungi were reduced in varying degrees and bacteria/fungi ratio was increased by 5–10 times. The enzyme activities, p H, and organic matter were increased, but soil bulk density was decreased. Phenolic acids such as phloridzin was decreased significantly. The copy number of four Fusarium species declined by 85.59%, 74.94%, 69.68%, and 54.41% after rotating three different crops(R3 treatment). The root volatiles of three plants inhibited mycelial growth and spore germination of four Fusarium species.

Study of glass transition kinetics of As_2S_3 and As_2Se_3 by ultrafast differential scanning calorimetry

Ultrafast differential scanning calorimetry(DSC) was employed to investigate the glass transition kinetics of As_2S_3 and As_2Se_3 . By using the Arrhenius method, a fragility index of～22 can be estimated in both As_2S_3 and As_2Se_3 .However, when the scanning rate is more than 200 K·s^(-1), non-Arrhenius behavior can be observed in such "strong" liquids where the Vogel–Fulcher method is more accurate to describe the glass transition kinetics. The fragilities of As_2S_3 and As_2Se_3 glasses are thus extrapolated as 28.3±1.94 and 23.7±1.80, respectively. This indicates that, As_2Se_3 glass has a better structural stability and it is a better candidate for device applications.

Evaluation and prediction of earth pressure balance shield performance in complex rock strata:A case study in Dalian,China

This research explores the potential for the evaluation and prediction of earth pressure balance shield performance based on a gray system model.The research focuses on a shield tunnel excavated for Metro Line 2 in Dalian,China.Due to the large error between the initial geological exploration data and real strata,the project construction is extremely difficult.In view of the current situation regarding the project,a quantitative method for evaluating the tunneling efficiency was proposed using cutterhead rotation(R),advance speed(S),total thrust(F)and torque(T).A total of 80 datasets with three input parameters and one output variable(F or T)were collected from this project,and a prediction framework based gray system model was established.Based on the prediction model,five prediction schemes were set up.Through error analysis,the optimal prediction scheme was obtained from the five schemes.The parametric investigation performed indicates that the relationships between F and the three input variables in the gray system model harmonize with the theoretical explanation.The case shows that the shield tunneling performance and efficiency are improved by the tunneling parameter prediction model based on the gray system model.

Isolation of phloridzin-degrading,IAA-producing bacterium Ochrobactrum haematophilum and its effects on the apple replant soil environment

We isolated and identified a bacterium that could produce IAA and degrade phloridzin in the rhizosphere soil of healthy replanted apple(the rootstock is M9T337 and the scion is Yanfu 3),providing a theoretical basis for reducing the obstacles associated with apple replant disease(ARD).Isolates were screened using Salkowski colorimetry and screening medium for phloridzin.The isolate of interest(W6)was identified as Ochrobactrum haematophilum based on morphological analysis,physiological and biochemical tests,and 16S rDNA sequencing.In a laboratory experiment,W6 produced auxin and promoted the growth of Arabidopsis thaliana roots,and its degradation rate of 100 mg.L^(-1 )phloridzin was 62.0%.In a pot experiment,W6 significantly reduced the phenolic acid contents of replanted soil,lowered the abundance of the harmful fungus Fusarium solani,and increased soil enzyme activities,thereby improving the micro-ecological environment of replant soil.W6 increased the root antioxidant enzyme activity and leaf photosynthetic pigment content of replanted Malus hupehensis Rehd.seedlings,effectively alleviating the decrease in net photosynthetic rate,transpiration rate and stomatal conductance caused by ARD.In a field experiment,W6 also promoted the growth of replanted apple(the rootstock is M9T337 and the scion is Yanfu 3)saplings.Therefore,W6 can promote apple growth and degrade phenolic acids,and it can be used as an effective treatment for the reduction of ARD.

Ultrabroadband mid-infrared emission from Cr^(2+):ZnSe-doped chalcogenide glasses prepared via hot uniaxial pressing and melt-quenching

We reported an ultrabroadband mid-infrared(MIR)emission in the range of 1800 nm-3100 nm at room temperature(RT)from a Cr^(2+):ZnSe-doped chalcogenide glasses(ChGs)and studied the emission-dependent properties on the doping methods.A series of Cr^(2+):ZnSe/As_(40)S_(57)Se_(3)(in unit wt.%)glass-ceramics were prepared by hot uniaxial pressing(HUP)and melt-quenching methods,respectively.The glass-ceramics with MIR emission bands greater than 1000 nm were successfully prepared by both methods.The effects of matrix glass composition and grain doping concentration on the optical properties of the samples were studied.The occurrence state,morphology of the grains,and the microscopic elemental distributions were characterized using x-ray diffraction(XRD),scanning electron microscope(SEM),and energy dispersive spectrometer(EDS)analyses.

Thermal stability of magnetron sputtering Ge-Ga-S films

Ge-Ga-S thin films were deposited by magnetron sputtering with mean coordination number(MCN)ranging from 2.46 to 2.94.The physical properties of the Ge-Ga-S films,including optical band gap,refractive index,and thickness,vary with the time of heat treatment.Based on the analysis of the topology model,it is concluded that the Ge-Ga-S thin films with components close to the stoichiometric ratio can form the most Ga-S bonds and Ga-S bonds,and the physical properties of the Ge27.3Ga6.3S66.3(MCN=2.62)film are the most stable.This is an important reference for thin film photonic devices.

川南地区ABO血型与不同病理类型肺癌的关系

目的探讨川南地区ABO血型与不同病理类型肺癌的关系。方法回顾性分析西南医科大学附属医院2017年8月—2020年12月收治的903例肺癌患者(肺癌组)的临床资料和ABO血型。根据病理类型将肺癌组分为小细胞肺癌组(n=154)和非小细胞肺癌组(n=749),后者再分为肺腺癌组(n=442)、肺鳞癌组(n=307)。选取该院同期1061例健康体检者为对照组。比较各肺癌组与对照组的ABO血型分布。结果肺鳞癌组的ABO血型分布为A型(31.9%)、B型(39.7%)、O型(21.2%)、AB型(7.2%),对照组的ABO血型分布为A型(32.2%)、B型(24.4%)、O型(35.7%)、AB型(7.6%),两组的血型构成比较,差异有统计学意义(P<0.001)。调整年龄、性别、吸烟史及饮酒史后,多因素Logistic回归分析显示:B型血患肺鳞癌的风险较O型血高(P<0.05),年龄<60岁患肺鳞癌风险较年龄≥60岁低(P<0.05),不吸烟者患肺鳞癌风险较吸烟者低(P<0.05)。小细胞肺癌组、肺腺癌组与对照组ABO血型构成比较,差异无统计学意义(P>0.05)。结论川南地区ABO血型与肺鳞癌的发生可能有相关性,与小细胞肺癌、肺腺癌无相关性。

Analysis of Leaf Volatiles of Crabapple (<i>Malus</i>sp.) Individuals in Different Aphids’ Resistance

The aim of this experiment was to analyze the leaf volatiles of crabapple (Malus sp.) individuals at different aphid’s resistance, to ascertain the particular ingredients which has lure or aversion effects on aphid, and to provide reference for finding out a simple method to control effectively aphids. Volatiles of leaves from twenty-one different crabapple individuals were evaluated with the method of head space-solid phase micro-extraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS). Volatiles profiles of them were then compared. There are one hundred eighty-six kinds of volatiles were detected with varied contents found in different individuals. And all plants contain eight kinds of common components: 3-Hexen-1-ol, acetate, (Z)-, 4-Hexen-1-ol, (Z)-, n-Decanal, n-Tetradecane, .alpha.-Farnesene, Diethyl Phthalate, Oxime-, methoxy-phenyl- and Dibenzofuran-, wherein the relative content of higher have 3-Hexen-1-ol, acetate, (Z)- and 4-Hexen-1-ol, (Z)-. Specific volatile substances in high resistance plants contain 3-Hexenal, (Z)- and 2-Hexenal, (E)-. Leaf volatiles differ in twenty-one crabapple individuals. High resistance plants specific volatile substances contains 3-Hexenal, (Z)-, 2-Hexenal, (E)- and other small molecular volatile substances, and no-resistance plants all have .beta.-Farnesene.

Variable angle spectroscopic ellipsometry and its applications in determining optical constants of chalcogenide glasses in infrared

The principle of variable angle spectroscopic ellipsometry（VASE） and the data analysis models, as well as the applications of VASE in the characterization of chalcogenide bulk glasses and thin films are reviewed. By going through the literature and summarizing the application scopes of various analysis models, it is found that a combination of various models, rather than any single data analysis model, is ideal to characterize the optical constants of the chalcogenide bulk glasses and thin films over a wider wavelength range. While the reliable optical data in the mid-and far-infrared region are limited, the VASE is flexible and reliable to solve the issues, making it promising to characterize the optical properties of chalcogenide glasses.

Effect of thickness of antimony selenide film on its photoelectric properties and microstructure

Antimony selenide(Sb2Se3) films are widely used in phase change memory and solar cells due to their stable switching effect and excellent photovoltaic properties. These properties of the films are affected by the film thickness. A method combining the advantages of Levenberg–Marquardt method and spectral fitting method(LM–SFM) is presented to study the dependence of refractive index(RI), absorption coefficient, optical band gap, Wemple–Di Domenico parameters, dielectric constant and optical electronegativity of the Sb2Se3films on their thickness. The results show that the RI and absorption coefficient of the Sb2Se3films increase with the increase of film thickness, while the optical band gap decreases with the increase of film thickness. Finally, the reasons why the optical and electrical properties of the film change with its thickness are explained by x-ray diffractometer(XRD), energy dispersive x-ray spectrometer(EDS), Mott–Davis state density model and Raman microstructure analysis.

Design and fabrication of GeAsSeS chalcogenide waveguides with thermal annealing

We reported a chalcogenide glass-based rib waveguide fabricated using photolithography and dry etching method. A commercial software(COMSOL Multiphysics) was used to optimize the waveguide structure and the distribution of the fundamental modes in the waveguide based on the complete vector finite component. We further employed thermal annealing to optimize the surface and sidewalls of the rib waveguides. It was found that the optimal annealing temperature for Ge As Se S films is 220℃, and the roughness of the films could be significantly reduced by annealing. The zero-dispersion wavelength(ZDW) could be shifted to a short wavelength around ~2.1 μm via waveguide structural optimization, which promotes supercontinuum generation with a short wavelength pump laser source. The insertion loss of the waveguides with cross-sectional areas of 4.0 μm×3.5 μm and 6.0 μm×3.5 μm was measured using lens fiber and the cut-back method. The propagation loss of the 220℃ annealed waveguides could be as low as 1.9 d B/cm at 1550 nm.