Achene mucilage formation process and extrusion from hydrated pericarp of Mirabilis himalaica

Myxospermy is an important feature of achenes of the alpine plant Mirabilis himalaica,and the achene mucilage increases the germination rate and early seedling growth during exposure to abiotic stresses,which has important functions that allow M.himalaica to survive the extreme climate of the Tibet Plateau.However,achene formation and mucilage extrusion are poorly understood.In the present study,comprehensive analyses were performed on mucilage production during achene development and mucilage release from hydrated achene pericarp in M.himalaica.First,fertilization initiated the development of M.himalaica achenes,during which their color,size and texture were altered dramatically.Second,using a metachromatic staining procedure,cytological events,the establishment of mucilage secretory cells in the inner epicarp layer were observed.The hydration of mature achenes led to the rapid bursting of mucilage secretory cells,which released a hydrophilic gel that surrounded the achenes.Finally,enzymatic digestion indicated that major components of the mucilage were pectins;glucose(41.40%),rhamnose(26.58%),galactose(18.33%),trehalose(12.12%),and mannose(1.57%)were found to be the components of achene by using ion-exchange chromatography.

人工智能三维重建辅助规划胸腔镜肺段切除术的应用价值

背景与目的三维重建可辅助规划肺段切除手术,基于人工智能算法的三维重建软件正逐步应用于临床中。本研究旨在评估人工智能三维重建辅助规划胸腔镜肺段切除术的准确性及安全性。方法共纳入兰州大学第二医院胸外科收治的90例经评估拟行胸腔镜肺段切除术的患者,术前使用人工智能三维重建软件制作肺三维图像并进行术前规划,术中保存手术录像,记录围手术期数据。选取38例患者的视频录像,探究人工智能三维重建对于手术规划的效能。将人工智能三维重建图像及Mimics 21软件重建结果与术中实际所见进行对比,比较两种重建方法对支气管、血管的检测及分型能力。结果90例患者均在人工智能三维重建规划下完成手术,其中单一肺段切除57例(63.3%),联合亚段切除33例(36.7%)。人工智能三维重建对病变定位的准确率为100.0%,计算机断层扫描(computed tomography,CT)报告准确率为94.4%(85/90)。人工智能三维重建和Mimics 21软件的检测准确率分别为92.1%(35/38)和89.5%(34/38),解剖分型准确率分别为89.5%(34/38)和84.2%(32/38),总准确率分别为76.3%(29/38)和71.1%(27/38)。在对38例手术视频与重建图像的对比观察中发现,使用人工智能三维重建进行术前规划的靶段规划、手术入路、动脉离断、静脉离断、支气管离断的一致率分别为92.1%(35/38)、92.1%(35/38)、89.5%(34/38)、86.8%(33/38)、94.7%(36/38),总规划操作一致率为68.4%(26/38)。结论使用人工智能三维重建辅助规划胸腔镜肺段切除术是准确且安全的。

基于生物信息学数据探究PKIG与肺鳞癌的相关性及其在肿瘤微环境中的作用

背景与目的肺癌是全球癌症相关死亡的主要原因,患者从手术、放疗和化疗这些传统治疗方法中生存获益有限。免疫疗法作为肺癌的一种新兴治疗手段,显著延长了患者的总生存期(overall survival,OS),然而,仅有一部分患者能够从中获益,需要我们更深入地探索免疫治疗生物标志物以筛选优势人群。方法从癌症基因组图谱(The Cancer Genome Atlas,TCGA)和基因表达综合数据库(Gene Expression Omnibus,GEO)下载原始数据,利用R软件和TIMER数据库筛选肺鳞癌(lung squamous cell carcinoma,LUSC)免疫预后相关基因。在TCGA和GEO数据库中研究了目标基因的表达情况,并通过R软件和TISIDB数据库对目标基因进行基因本体(Gene Ontology,GO)和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析以及与肿瘤免疫特征之间的相关性分析。结果我们筛选出cAMP依赖性蛋白激酶抑制剂γ(protein kinase inhibitor gamma,PKIG)这个免疫预后相关基因,PKIG在LUSC和正常组织中的表达有明显差异,并对LUSC的诊断和预后评估具有重要参考价值。PKIG差异基因主要集中富集在体液免疫反应的调节等过程。PKIG的表达与调节性T细胞(regulatory T cells,Tregs)的浸润水平呈正相关(r=0.340,P<0.001)。此外,PKIG还与LUSC中趋化因子配体2(chemokine C-C motifligand 2,CCL2)(r=0.503,P<0.001)、CXC趋化因子配体12(CXC chemokine ligand 12,CXCL12)(r=0.386,P<0.001)和CXC趋化因子受体4(CXC-chemokine receptor 4,CXCR4)(r=0.492,P<0.00l)等趋化因子/趋化因子受体以及细胞程序性死亡蛋白1(programmed cell death protein 1,PDCD1)(r=0.359,P<0.001)、细胞毒性T淋巴细胞相关蛋白4(cytotoxic T-lymphocyte associated antigen 4,CTLA4)(r=0.375,P<0.001)和T细胞免疫球蛋白ITIM结构域(T cell immunoglobulin and ITIM domains,TIGIT)(r=0.305,P<0.001)等免疫抑制剂的表达水平呈正相关。结论通过生物信息学分析筛选出LUSC免疫预后相关基因PKIG,PKIG与LUSC预后和免疫微环境高度相关,有望成为LUSC免疫治疗的潜在生物分子标志物。

A new species and a new record of free-living marine nematode of genus Diplolaimelloides(Monhysteridae)from Futian mangrove reservation in Shenzhen,China

A new species and a new record of free-living marine nematode of genus Diplolaimelloides’(Monhysteridae)inhabiting the sediment of mangrove reservation in Shenzhen,China are described and illustrated.Diplolaimelloides contortus sp.nov.is characterized by the combination of the following characters:ocelli present;four pairs of post-cloacal papillae arranged in(2+2)pattern,two midway on bursa and two near posterior extremities;spicules complicated in shape,twisted and curved at middle portion;gubernaculum wedge-shaped,with distal dorsal ridge well cuticularized,proximal dorsal ridge obscure sleeve-like,proximal end wrap the spicule;vulva located at 52.1%-53.6%of body length;male tail slender,10.0-11.4 times of anal body diameter,and female tail long filiform,13.1-13.6 times of anal body diameter.Diplolaimelloides delyi Andras sy,1958 is first recorded from China and redescribed in detail,it differs from the original description by Andrassy in 1958 for having larger body size of male,shorter tail,and posterior situation of vulva.However,it is much conform to the redescription to specimens from East Pakistan by Timm in 1966,except for shorter tail in female and absent pre-anal seta.Specimens are deposited in the Institute of Oceanology,Chinese Academy of Sciences.

3D视频在医学教育中应用的范围综述

目的3D视频在医学教育中的应用方兴未艾。本研究旨在综述3D视频在医学教育中的应用以及对课程活动的影响,为未来该领域的研究提供参考。方法遵循Arksey和O'malley的范围综述指南,采用系统检索策略检索9个英文文献数据库,仅纳人原始文献。2名作者根据纳人排除标准独立筛选了所有文献,并对最终纳入的原始研究文献进行了分析。结果共检索到1302篇文献,最终纳入了23篇。从文献中获得的3个主题包括:在医学教育中使用3D视频的优势,使用3D视频对学生学业成绩和能力的影响,以及学生关于医学教育中使用3D视频的体验。结论在医学教育中使用3D视频得到了广大学生和教育工作者的支持。然而,3D视频在医学教育中的应用效果仍存在争议。医学教育工作者应结合课程特点、学生学习情况和现有教育资源合理使用。

Role of mucilage during achene germination and sprout growth of the endangered Tibetan medicinal herb Mirabilis himalaica (Nyctaginaceae) exposed to abiotic stresses

Aim Mirabilis himalaica(Nyctaginaceae)is an endangered medicinal plant mainly distributed in the plateau region of northern Tibet,China.The outer surface of M.himalaica achenes is covered by a pectinaceous mucilaginous layer upon hydration.However,the role of the achene mucilage is poorly understood.in this study,we inves-tigated the effects of mucilage on achene germination and sprout growth under abiotic stress to explain how M.himalaica survive the alpine environment.Methods We investigated the effect of mucilage on achenes germination by contrast the capacity of water absorption,dehydration and respira-tion of intact achene and the achene with mucilage removal.We performed abiotic stresses experiments including drought stress,salt stress,cold stress and high temperature stress,and quantified the effects of mucilage removal on achene germination rate,root and shoot lengths of seedlings.Important Findings Mucilage is extremely hydrophilic,and the mass of intact achenes can be 9-fold greater than that of demucilaged achenes.The removal of the mucilaginous layer did not significantly change final germination percentages under ideal conditions,but intact achenes(i.e.with muci-lage)took longer to germinate.The mucilage significantly decreased seed respiration rates by acting as a physical barrier that prevented oxygen diffusion.Germination rates,shoot and root growth of intact achenes were higher than those of demucilaged ones during exposures to cold,heat,osmotic and salt stresses.Achene mucilage presumably plays an ecologically important role in the life cycle of M.himalaica by aiding the critical achene germination and early seedling growth in the stressful habitats of the plateau region of northern Tibet.

Static analysis of elastic cable structures under mechanical load using discrete catenary theory

In this paper,the nonlinear mechanical response of elastic cable structures under mechanical load is studied based on the discrete catenary theory.A cable net is discretized into multiple nodes and edges in our numerical approach,which is followed by an analytical formulation of the elastic energy and the associated Hessian matrix to realize the dynamic simulation.A fully implicit framework is proposed based on the discrete differential geometry(DDG)theory.The equilibrium configuration of a target object is derived by adding damping force into the system,known as the dynamic relaxation method.The mechanical response of a single suspended cable is investigated and compared with the analytical solution for cross-validation.A more intricate scenario is further discussed in detail,where a structure consisting of multiple slender cables is connected through joints.Utilizing the robustness and efficiency of our discrete numerical framework,a systematic parameter sweep is performed to quantify the force displacement relationships of nets with the different number of cables and different directions of fibers.Finally,an empirical scaling law is provided to account for the rigidity of elastic cable net in terms of its geometric properties,material characteristics,component numbers,and cable orientations.Our results would provide new insight in revealing the connections between flexible structures and tensegrity structures,and could motivate innovative designs in both mechanical and civil engineered equipment.

Facile synthesis of graphene-supported Ni-CeOx nano-composites as highly efficient catalysts for hydrolytic dehydrogenation of ammonia borane

Development of low-cost and high-performance catalysts for hydrogen generation via hydrolysis of ammonia borane （NH3BH3, AB） is a highly desirable pathway for future hydrogen utilization. In this work, Ni nanocatalysts doped with CeOx and supported on graphene （Ni-CeOdgraphene） were synthesized via a facile chemical reduction route and applied as robust catalysts for the hydrolysis of AB in aqueous solution at room temperature. The as-synthesized Ni-CeOdgraphene nanocomposites （NCs） exhibited excellent catalytic activity with a turnover frequency （TOF） as high as 68.2 min-1, which is 49-fold higher than that for a simple Ni nanoparticle catalyst and is among the highest values reported for non-noble metal catalysts in AB hydrolysis. The development of efficient and low-cost Ni-CeOdgraphene catalysts enhances the feasibility of using ammonia borane as a chemical hydrogen storage material, which may find application in a hydrogen fuel-cell based economy.

Smartphone-powered iontophoresis-microneedle array patch for controlled transdermal delivery

The incidence rate of diabetes has been increasing every year in nearly all nations and regions.The traditional control of diabetes using transdermal insulin delivery by metal needles is generally associated with pain and potential infections.While microneedle arrays(MAs)have emerged as painless delivery techniques,the integration of MA systems with electronic devices to precisely control drug delivery has rarely been realized.In this study,we developed an iontophoresis-microneedle array patch(IMAP)powered by a portable smartphone for the active and controllable transdermal delivery of insulin.The IMAP in situ integrates iontophoresis and charged nanovesicles into one patch,achieving a one-step drug administration strategy of“penetration,diffusion and iontophoresis”.The MA of the IMAP is first pressed on the skin to create microholes and then is retracted,followed by the iontophoresis delivery of insulin-loaded nanovesicles through these microholes in an electrically controlled manner.This method has synergistically and remarkably enhanced controlled insulin delivery.The amount of insulin can be effectively regulated by the IMAP by applying different current intensities.This in vivo study has demonstrated that the IMAP effectively delivers insulin and produces robust hypoglycemic effects in a type-1 diabetic rat model,with more advanced controllability and efficiency than delivery by a pristine microneedle or iontophoresis.The IMAP system shows high potential for diabetes therapy and the capacity to provide active as well as long-term glycemic regulation without medical staff care.

Identification of various food residuals on denim based on hyperspectral imaging system and combination optimal strategy

As the science and technology develop,crime methods and scenes have become increasingly complex and diverse.Trace evidence analysis has become amore and more important criminal investigation technology and liquid is the main form of trace evidence.Food can provide not only energy,but clues to solve crimes.In this study,we build a hyperspectral imaging system to detect liquid residue traces,including apple juice,coffee,cola,milk and tea,on denims with light,middle and dark colors.The obtained hyperspectral images are first subjected to spectral calibration and hyperspectral data pretreatment.Subsequently,Partial Least Squares(PLS)is applied to select the informative wavelengths from the preprocessed spectra.For modeling phase,the combination optimal strategy,support vector machine(SVM)combined with random forest(RF),is developed to establish classification models.The experimental results demonstrate that the combination optimal model can achieve TPR,FPR,Precision,Recall,F1,and AUC of 83.5%,2.30%,79.7%,83.5%,81.6%,and 94.7%for classifying fabrics contaminated by various food residuals.With respect to the classification of liquid and fabric types,the combination optimalmodel also yields satisfactory classification performance.In future work,wewill expand the types of liquid,and make appropriate adjustment to algorithms for improving the robustness of classification models.This research may play a positive role in the construction of a harmonious society.