A froth velocity measurement method based on improved U-Net++semantic segmentation in flotation process

During flotation,the features of the froth image are highly correlated with the concentrate grade and the corresponding working conditions.The static features such as color and size of the bubbles and the dynamic features such as velocity have obvious differences between different working conditions.The extraction of these features is typically relied on the outcomes of image segmentation at the froth edge,making the segmentation of froth image the basis for studying its visual information.Meanwhile,the absence of scientifically reliable training data with label and the necessity to manually construct dataset and label make the study difficult in the mineral flotation.To solve this problem,this paper constructs a tungsten concentrate froth image dataset,and proposes a data augmentation network based on Conditional Generative Adversarial Nets(cGAN)and a U-Net++-based edge segmentation network.The performance of this algorithm is also evaluated and contrasted with other algorithms in this paper.On the results of semantic segmentation,a phase-correlationbased velocity extraction method is finally suggested.

Unified deep learning model for predicting fundus fluorescein angiography image from fundus structure image

The prediction of fundus fluorescein angiography(FFA)images from fundus structural images is a cutting-edge research topic in ophthalmological image processing.Prediction comprises estimating FFA from fundus camera imaging,single-phase FFA from scanning laser ophthalmoscopy(SLO),and three-phase FFA also from SLO.Although many deep learning models are available,a single model can only perform one or two of these prediction tasks.To accomplish three prediction tasks using a unified method,we propose a unified deep learning model for predicting FFA images from fundus structure images using a supervised generative adversarial network.The three prediction tasks are processed as follows:data preparation,network training under FFA supervision,and FFA image prediction from fundus structure images on a test set.By comparing the FFA images predicted by our model,pix2pix,and CycleGAN,we demonstrate the remarkable progress achieved by our proposal.The high performance of our model is validated in terms of the peak signal-to-noise ratio,structural similarity index,and mean squared error.

Imaging of human parafoveal area with large field of view in adaptive optics line scanning ophthalmoscope

The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological changes.The current adaptive optics scanning laser ophthalmoscope(AOSLO)provides an excellent tool to acquire accurate and detailed information about the parafoveal area with cellular resolution.However,limited by the scanning speed of two-dimensional scanning,thefield of view(FOV)in the AOSLO system was usually less than or equal to 2,and the stitching for the parafoveal area required dozens of images,which was time-consuming and laborious.Unfortunately,almost half of patients are unable to obtain stitched images because of their poorfixation.To solve this problem,we integrate AO technology with the line-scan imaging method to build an adaptive optics line scanning ophthalmoscope(AOLSO)system with a larger FOV.In the AOLSO,afocal spherical mirrors in pairs are nonplanar arranged and the distance and angle between optical elements are optimized to minimize the aberrations,two cylinder lenses are orthogonally placed before the imaging sensor to stretch the point spread function(PSF)for su±ciently digitizing light energy.Captured human retinal images show the whole parafoveal area with 55FOV,60 Hz frame rate and cellular resolutions.Take advantage of the 5FOV of the AOLSO,only 9 frames of the retina are captured with several minutes to stitch a montage image with an FOV of 99,in which photoreceptor counting is performed within approximately 5eccentricity.The AOLSO system not only provides cellular resolution but also has the capability to capture the parafoveal region in a single frame,which offers great potential for noninvasive studying of the parafoveal area.

Effective Improvement of the Photovoltaic Performance of Carbon-Based Perovskite Solar Cells by Additional Solvents

A solvent-assisted methodology has been developed to synthesize CH_3NH_3 PbI_3perovskite absorber layers.It involved the use of a mixed solvent of CH_3NH_3 I,PbI_2,c-butyrolactone,and dimethyl sulfoxide(DMSO) followed by the addition of chlorobenzene(CB).The method produced ultra-flat and dense perovskite capping layers atop mesoporous TiO_2 films,enabling a remarkable improvement in the performance of free hole transport material(HTM) carbon electrode-based perovskite solar cells(PSCs).Toluene(TO) was also studied as an additional solvent for comparison.At the annealing temperature of 100 °C,the fabricated HTM-free PSCs based on drop-casting CB demonstrated power conversion efficiency(PCE) of 9.73 %,which is 36 and 71 % higher than those fabricated from the perovskite films using TO or without adding an extra solvent,respectively.The interaction between the PbI_2–DMSO–CH_3NH_3I intermediate phase and the additional solvent was discussed.Furthermore,the influence of the annealing temperature on the absorber film formation,morphology,and crystalline structure was investigated and correlated with the photovoltaic performance.Highly efficient,simple,and stable HTM-free solar cells with a PCE of 11.44 % were prepared utilizing the optimum perovskite absorbers annealed at 120 °C.

Clinical study of transcatheter occlusion in treating ventricular septal defect combined with right coronary cusp bulge

Background: Perimembranous ventricular septal defect combined with right coronary cusp bulge generally should be treated with surgical thoracotomy, owing to the potential aortic regurgitation. However, the minimally invasive method of transcatheter closure has always attracted the attention of cardiologists and patients. The present study aimed to apply transcatheter occlusion in treating ventricular septal defect with right coronary cusp bulge and further evaluate the clinical effect through follow-up. Materials and methods: A total of 40 children diagnosed as having a ventricular septal defect with right coronary cusp bulge, examined using transthoracic echocardiography and cardiovascular angiography, were enrolled in this study. The ventricular septal defects were closed by placing occluders through transcatheter occlusion treatment. During the operation process, the children underwent angiography and transthoracic echocardiography examinations to check the position of the occlude and the extent of aortic regurgitation. The influence of occlusion on the conduction system was evaluated using a surface electrocardiogram. The children were followed up after their procedures. Results: All 40 patients were immediately and successfully occluded. Three patients with filament residual shunts were observed during the operations. No major surgical complications occurred during the perioperative period. During the follow-up period, the positions of all the occluders were good, the residual shunts in the three patients disappeared, and no new or aggravated aortic regurgitation occurred. Electrocardiogram did not reveal any atrioventricular blocks. Only one patient suffered from an incomplete right bundle branch block. Conclusions: Children diagnosed with ventricular septal defect combined with right coronary cusp bulge could be considered for transcatheter occlusion. With appropriate indications and methods, the effect may be favorable.

Automated cone photoreceptor cell identication in confocal adaptive optics scanning laser ophthalmoscope images based on object detection

Cone photoreceptor cell identication is important for the early diagnosis of retinopathy.In this study,an object detection algorithm is used for cone cell identication in confocal adaptive optics scanning laser ophthalmoscope(AOSLO)images.An effectiveness evaluation of identication using the proposed method reveals precision,recall,and F_(1)-score of 95.8%,96.5%,and 96.1%,respectively,considering manual identication as the ground truth.Various object detection and identication results from images with different cone photoreceptor cell distributions further demonstrate the performance of the proposed method.Overall,the proposed method can accurately identify cone photoreceptor cells on confocal adaptive optics scanning laser ophthalmoscope images,being comparable to manual identication.

Accuracy characterization of Shack-Hartmann sensor with residual error removal in spherical wavefront calibration

The widely used Shack-Hartmann wavefront sensor(SHWFS)is a wavefront measurement system.Its measurement accuracy is limited by the reference wavefront used for calibration and also by various residual errors of the sensor itself.In this study,based on the principle of spherical wavefront calibration,a pinhole with a diameter of 1μm was used to generate spherical wavefronts with extremely small wavefront errors,with residual aberrations of 1.0×10^(−4)λRMS,providing a high-accuracy reference wavefront.In the first step of SHWFS calibration,we demonstrated a modified method to solve for three important parameters(f,the focal length of the microlens array(MLA),p,the sub-aperture size of the MLA,and s,the pixel size of the photodetector)to scale the measured SHWFS results.With only three iterations in the calculation,these parameters can be determined as exact values,with convergence to an acceptable accuracy.For a simple SHWFS with an MLA of 128×128 sub-apertures in a square configuration and a focal length of 2.8 mm,a measurement accuracy of 5.0×10^(−3)λRMS was achieved across the full pupil diameter of 13.8 mm with the proposed spherical wavefront calibration.The accuracy was dependent on the residual errors induced in manufacturing and assembly of the SHWFS.After removing these residual errors in the measured wavefront results,the accuracy of the SHWFS increased to 1.0×10^(−3)λRMS,with measured wavefronts in the range ofλ/4.Mid-term stability of wavefront measurements was confirmed,with residual deviations of 8.04×10^(−5)λPV and 7.94×10^(−5)λRMS.This study demonstrates that the modified calibration method for a high-accuracy spherical wavefront generated from a micrometer-scale pinhole can effectively improve the accuracy of an SHWFS.Further accuracy improvement was verified with correction of residual errors,making the method suitable for challenging wavefront measurements such as in lithography lenses,astronomical telescope systems,and adaptive optics.

Viral load kinetics of the severe acute respiratory syndrome coronavirus 2 Omicron variant in children aged 0 to 3 years and their parents

The Omicron variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)was first confirmed in November 2021 in South Africa^([1])and is more transmissible than other sub-variants.^([2])The influence of Omicron in children has been recognized with increased hospital admission rate than Delta wave.^([3,4])But severe clinical outcomes and comorbidity of Omicron are less than Delta in children.^([5])Hospitalized children during the Omicron period were more likely to be younger than that in the pre-Omicron period.^([6])

Effects of Low-pressure Annealing on the Performance of 3D Printed CF/PEEK Composites

The interlayer bonding properties are normally unsatisfying for 3D printed composites owing to the layer-by-layer formation process.In this study,low-pressure annealing was performed on 3D printed carbon fiber reinforced polyether ether ketone(CF/PEEK)to improve the interlayer bonding strength.The effects of annealing parameters on the mechanical properties and microstructure were studied.The results showed that the interlaminar shear strength(ILSS)of CF/PEEK improved by up to 55.4%after annealing.SEM and𝜇-CT were also applied to reveal the reinforcing mechanism.This improvement could mainly be attributed to the increased crystallinity of the CF/PEEK after annealing.Additionally,annealing reduced the porosity of the printed CF/PEEK and improved the fiber-resin interface.This resulted in a reduction in the stress concentration areas during loading,thereby enhancing the interlayer bonding strength of CF/PEEK.

影响Omicron变异株感染轻型和普通型COVID-19患儿核酸转阴时间缩短因素分析

目的探讨Omicron变异株感染轻型与普通型新型冠状病毒疾病(COVID-19)患儿的临床特征及影响其核酸检测结果转为阴性(以下简称为"核酸转阴")时间缩短因素。方法选取2022年4月7日至5月20日上海交通大学医学院附属仁济医院南院区"亲子病房"集中收治的150例Omicron变异株感染轻型和普通型COVID-19患儿为研究对象。采用回顾性分析方法,根据这150例患儿的核酸转阴中位时间为13 d,将其分别纳入快转阴组(n=84,核酸转阴时间<13 d)和慢转阴组(n=66,核酸转阴时间≥13 d)。对2组患儿年龄、性别、轻型与普通型COVID-19患儿构成比、疫苗接种率、COVID-19相关临床表现及COVID-19发病48 h内系统炎症指数(SII)、中性粒细胞与淋巴细胞比值(NLR)、淋巴细胞与单核细胞比值(LMR)、血小板与淋巴细胞比值(PLR)等,进行成组t检验、Mann-Whitney U检验或χ2检验。采用多因素非条件logistic回归分析方法,分析影响Omicron变异株感染轻型与普通型COVID-19患儿核酸转阴时间缩短的因素。2组患儿合并基础疾病占比、采取对症治疗率等一般临床资料分别比较,差异均无统计学意义(P>0.05)。本研究遵循的程序符合2013修订的《世界医学协会赫尔辛基宣言》要求。结果①快转阴组患儿年龄、女性患儿比例、普通型COVID-19患儿比例、疫苗接种率,发热、咽痛、胃肠道症状发生率,均显著高于慢转阴组,而热峰、肌肉酸痛发生率,则均显著低于慢转阴组,2组比较,差异均有统计学意义(P<0.05)。②多因素非条件logistic回归分析结果显示,伴有咽痛、接种疫苗是轻型与普通型COVID-19患儿核酸转阴时间缩短的独立保护因素(OR=14.609、7.866,95%CI:1.108~192.697、1.313~47.121,P=0.042、0.024),而伴有肌肉酸痛、男性患儿则是其独立危险因素(OR=0.275、0.206,95%CI:0.087~0.874、0.083~0.511,P=0.029、0.001)。③快转阴组患儿SII为250.9×109/L(111.1×109/L,466.9×109/L),NLR为1.0(0.6,2.2),均分别显著高于慢转阴组的109.8×109/L(47.2×109/L,266.7×109/L)与0.5(0.2,1.2),并且差异均有统计学意义(Z=6.48、5.34,P=0.011、0.021)。快转阴组患儿LMR为4.1(2.5,9.4),显著低于慢转阴组的8.2(3.4,11.1),并且差异有统计学意义(Z=4.50,P=0.034)。结论轻型与普通型COVID-19患儿临床表现不典型,以发热、咳嗽为主,高SII、NLR及低LMR患儿核酸转阴时间较短,接种疫苗、伴有咽痛是促进核酸转阴时间缩短的保护性因素,伴有肌肉酸痛及男性是影响核酸转阴时间缩短的危险因素。

Vegfa signaling regulates diverse artery/vein formation in vertebrate vasculatures

Vascular endothelial growth factor A（Vegfa） signaling regulates vascular development during embryogenesis and organ formation.However,the signaling mechanisms that govern the formation of various arteries/veins in various tissues are incompletely understood.In this study,we utilized transcription activator-like effector nuclease（TALEN） to generate zebrafish vegfaa mutants.vegfaa^-/- embryos are embryonic lethal,and display a complete loss of the dorsal aorta（DA） and expansion of the cardinal vein.Activation of Vegfa signaling expands the arterial cell population at the expense of venous cells during vasculogenesis of the axial vessels in the trunk.Vegfa signaling regulates endothelial cell（EC） proliferation after arterial-venous specification.Vegfa deficiency and overexpression inhibit the formation of tip cell filopodia and interfere with the pathfinding of intersegmental vessels（ISVs）.In the head vasculature,vegfaa^-/- causes loss of a pair of mesencephalic veins（MsVs） and central arteries（CtAs）,both of which usually dvelop via sprouting angiogenesis.Our results indicate that Vegfa signaling induces the formation of the DA at the expense of the cardinal vein during the trunk vasculogenesis,and that Vegfa is required for the angiogenic formation of MsVs and CtAs in the brain.These findings suggest that Vegfa signaling governs the formation of diverse arteries/veins by distinct cellular mechanisms in vertebrate vasculatures.

Automated superpixels-based identification and mosaicking of cone photoreceptor cells for adaptive optics scanning laser ophthalmoscope

An automated superpixels identification/mosaicking method is presented for the analysis of cone photoreceptor cells with the use of adaptive optics scanning laser ophthalmoscope(AO-SLO) images. This is an image oversegmentation method used for the identification and mosaicking of cone photoreceptor cells in AO-SLO images.It includes image denoising, estimation of the cone photoreceptor cell number, superpixels segmentation, merging of superpixels, and final identification and mosaicking processing steps. The effectiveness of the presented method was confirmed based on its comparison with a manual method in terms of precision, recall, and F1-score of 77.3%, 95.2%, and 85.3%, respectively.

Personalized cancer vaccines from bacteria-derived outer membrane vesicles with antibody-mediated persistent uptake by dendritic cells

Nanocarriers with intrinsic immune adjuvant properties can activate the innate immune system while delivering tumor antigen,thus efficiently facilitating antitumor adaptive immunity.Bacteria-derived outer membrane vesicles(OMVs)are an excellent candidate due to their abundance of pathogen associated molecular patterns.However,during the uptake of OMVs by dendritic cells(DCs),the interaction between lipopolysaccharide and toll-like receptor 4 induces rapid DC maturation and uptake blockage,a phenomenon we refer to as“maturation-induced uptake obstruction"(MUO).Herein we decorated OMV with the DC-targeting aDEC205 antibody(OMV-DEC),which endowed the nanovaccine with an uptake mechanism termed as 4<not restricted to maturation via antibody modifying”(Normandy),thereby overcoming the MUO phenomenon.We also proved the applicability of this nanovaccine in identifying the human tumor neoantigens through rapid antigen display.In summary,this engineered OMV represents a powerful nanocarrier for personalized cancer vaccines,and this antibody modification strategy provides a reference to remodel the DC uptake pattern in nanocarrier design.

Bronsted酸催化的2-萘偶氮邻位胺化反应

独特的分子结构和理化性质使得N-芳基咔唑类化合物在有机发光半导体(OLED)材料以及药物化学领域展现出了重要的应用潜力.因此,发展高效的、条件温和的合成策略实现N-芳基咔唑类骨架的构建具有十分重要的意义.传统过渡金属催化的N-芳基偶联策略需要芳烃原料的预官能化,同时副产物的产生也显著影响了该方法的合成效率.已报道的C-H/N-H脱氢偶联方法一般需要大量的氧化剂,而且存在反应条件剧烈、化学选择性差和底物普适性不足等诸多问题.本研究基于芳烃极性翻转策略,实现了一种Bronsted酸催化的芳烃C-H胺化途径用于N-芳基咔唑的高效构建,该方法反应条件温和、原子经济性高,且避免了对于金属催化剂的依赖.实验结果表明,磷酸与底物间的氢键作用以及催化剂上大共轭芳香基团与底物间的π-π堆积作用对该转化的化学选择性调控起到了至关重要的作用.

Nutrition Metabolism and Infections

Infection and nutrition are intricately interacted and further influence human health.Infections are a worldwide health problem and malnutrition plays a significant role in the emergence of infection.Growing evidence suggests that the optimization of dietary nutrients intake is crucial in maintaining systemic immunity and may help improve resistance to infections.In this review,we explore a wide range of topics including interactions between nutrients and various infectious diseases.We also discuss the role of diet-induced gut microbiota in the infection-nutrition cycle and review how dietary-microbiome crosstalk may affect disease development and progression,which may provide an attractive option to the design of a diet leading to favorable outcomes in the future.We will also present evidence and propose mechanisms of nutrients that may specifically modulate host immunity and metabolism to infectious pathogens and also cover its influence on nutrition,focusing on immuno-nutrients.We provide representative nutrients in the present review based on their intensive studies and wide acceptance of their immuno-modulating properties.Moreover,the efficacy and translational cost of their plausible utility to be anti-infective nutrients are also reviewed.Finally,we highlight the current progress and challenges to gain a better understanding of the research into microbiota,infectious diseases,and nutrition with an emphasis on future research directions.