Study on the variation in and selection of Fraxinus mandshurica provenances and families in northeast China

Fraxinus mandshurica Rupr.is one of the main afforestation species in northeast China,and there is great demand for improved F.mandshurica varieties.The results of an investigation into and analysis of the growth traits of F.mandshurica provenances and families showed that there were significant differences in different periods.However,variations in growth traits decreased year by year.There was a significant negative correlation between tree heights of the provenances and sunshine hours in their areas of origin.The provenances of Xinglong,Hailin and Wuchang were selected based on the volume of 18-year-old trees.The average genetic gain from the selection of fast-growing provenances was 19.4%.Ten superior fast-growing families were selected.The average volume of the selected families was22.6%,higher than that of all families.The correlation coefficient between heights at 6-year-old and at 18a was 0.838for provenances,and between heights at 4-year-old and at 18-year-old was 0.303 for families.These results indicate that early selection for height in provenances or families could be performed at 6 years or 4 years,respectively.Early selection for DBH and volume in families could start at 8 years.

Machine Learning Empowered Beam Management for Intelligent Reflecting Surface Assisted MmWave Networks

Recently,intelligent reflecting surface(IRS)assisted mmWave networks are emerging,which bear the potential to address the blockage issue of the millimeter wave(mmWave)communication in a more cost-effective way.In particular,IRS is built by passive and programmable electromagnetic elements that can manipulate the mmWave propagation channel into a more favorable condition that is free of blockage via judicious joint base station(BS)-IRS transmission design.However,the coexistence of IRSs and mmWave BSs complicates the network architecture,and thus poses great challenges for efficient beam management(BM)that is one critical prerequisite for high performance mmWave networks.In this paper,we systematically evaluate the key issues and challenges of BM for IRS-assisted mmWave networks to bring insights into the future network design.Specifically,we carefully classify and discuss the extensibility and limitations of the existing BM of conventional mmWave towards the IRS-assisted new paradigm.Moreover,we propose a novel machine learning empowered BM framework for IRS-assisted networks with representative showcases,which processes environmental and mobility awareness to achieve highly efficient BM with significantly reduced system overhead.Finally,some interesting future directions are also suggested to inspire further researches.

锌金属电镀过程中锌枝晶的生长行为及影响因素

电镀是电化学体系的重要组成部分。为拓宽学生的知识构架,培养学生的创新意识和科学素养,将锌电镀引入应用电化学专业本科实验教学。本实验以锌电镀过程中易产生锌枝晶的问题为出发点,先从理论上剖析其形成原因,据此提出表面异质性消除以及阳离子添加剂两种策略来抑制锌枝晶的产生;并设计通过搭建原位光学显微镜直接观测锌沉积行为变化,以加深学生对锌电镀过程的理解。本实验深入融合贯穿了前沿研究的科学思路与创新理念,引导学生跳出教材内容的框架,激发学生对科学研究的兴趣,有助于学生科学思维能力的培养。

Modeling and simulation of an anatomy teaching system

Specimen observation and dissection have been regarded as the best approach to teach anatomy,but due to the severe lack of anatomical specimens in recent years,the quality of anatomy teaching has been seriously affected.In order to disseminate anatomical knowledge effectively under such circumstances,this study discusses three key factors(modeling,perception,and interaction)involved in constructing virtual anatomy teaching systems in detail.To ensure the authenticity,integrity,and accuracy of modeling,detailed three-dimensional(3D)digital anatomical models are constructed using multi-scale data,such as the Chinese Visible Human dataset,clinical imaging data,tissue sections,and other sources.The anatomical knowledge ontology is built according to the needs of the particular teaching purposes.Various kinds of anatomical knowledge and 3D digital anatomical models are organically combined to construct virtual anatomy teaching system by means of virtual reality equipment and technology.The perception of knowledge is realized by the Yi Chuang Digital Human Anatomy Teaching System that we have created.The virtual interaction mode,which is similar to actual anatomical specimen observation and dissection,can enhance the transmissibility of anatomical knowledge.This virtual anatomy teaching system captures the three key factors.It can provide realistic and reusable teaching resources,expand the new medical education model,and effectively improve the quality of anatomy teaching.

How to select the quantitative magnetic resonance technique for subjects with fatty liver:A systematic review

BACKGROUND Early quantitative assessment of liver fat content is essential for patients with fatty liver disease.Mounting evidence has shown that magnetic resonance(MR)technique has high accuracy in the quantitative analysis of fatty liver,and is suitable for monitoring the therapeutic effect on fatty liver.However,many packaging methods and postprocessing functions have puzzled radiologists in clinical applications.Therefore,selecting a quantitative MR imaging technique for patients with fatty liver disease remains challenging.AIM To provide information for the proper selection of commonly used quantitative MR techniques to quantify fatty liver.METHODS We completed a systematic literature review of quantitative MR techniques for detecting fatty liver,following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol.Studies were retrieved from PubMed,Embase,and Cochrane Library databases,and their quality was assessed using the Quality Assessment of Diagnostic Studies criteria.The Reference Citation Analysis database(https://www.referencecitationanalysis.com)was used to analyze citation of articles which were included in this review.RESULTS Forty studies were included for spectroscopy,two-point Dixon imaging,and multiple-point Dixon imaging comparing liver biopsy to other imaging methods.The advantages and disadvantages of each of the three techniques and their clinical diagnostic performances were analyzed.CONCLUSION The proton density fat fraction derived from multiple-point Dixon imaging is a noninvasive method for accurate quantitative measurement of hepatic fat content in the diagnosis and monitoring of fatty liver progression.

Analyzing proteins in colonic tissues from mice with ulcerative colitis using the iTRAQ technology

Objective The aim of the study was to investigate the expression of proteins in colonic tissues of mice with ulcerative colitis(UC) by using isobaric tags for relative and absolute quantitation(iTRAQ), probe into the pathogenesis of UC, and find potential biomarkers of UC. Methods Forty C57 mice were randomly divided into the control and model groups(20 mice in each group). The mice in the model group were administered dextran sulphate sodium(DSS) for 7 consecutive days ad libitum to induce acute colitis, and the colon tissue was extracted on the 8 th day after the successful establishment of the UC model. Proteins were identified by the i TRAQ and tandem mass spectrometry techniques,and the identified proteins were analyzed by bioinformatics. Results A total of 4019 proteins were identified among the two groups. Among them, 317 significant differentially expressed proteins(DEPs) were detected according to the screening criteria for selecting DEPs, i.e. fold change ratios ≥ 1.5 or ≤ 0.67 and P-values < 0.05, of which 156 were upregulated and 161 were downregulated. In the Gene Ontology(GO) analysis, the DEPs were classified into 48 functional categories, which contained biological process, cellular component, and molecular function. Based on the 317 DEPs, the KEGG pathway analysis identified 160 vital pathways.Conclusion DEPs in colonic tissues of mice with UC were screened using the iTRAQ technique, which laid a foundation for further studies regarding the pathogenesis of UC.

The role of crm-1 in ionizing radiation-induced nervous system dysfunction in Caenorhabditis elegans

Ionizing radiation can cause changes in nervous system function.However,the underlying mechanism remains unclear.In this study,Coenorhabditis elegans(C.elegans)was irradiated with 75 Gy of ^(60)Co whole-body γ radiation.Behavioral indicators(head thrashes,touch avoidance,and foraging),and the development of dopaminergic neurons related to behavioral function,were evaluated to assess the effects of ionizing radiation on nervous system function in C.elegans.Various behaviors were impaired after whole-body irradiation and degeneration of dopamine neurons was observed.This suggests that 75 Gy of γ radiation is sufficient to induce nervous system dysfunction.The genes nhr-76 and crm-1,which are reported to be related to nervous system function in human and mouse,were screened by transcriptome sequencing and bioinformatics analysis after irradiation or sham irradiation.The expression levels of these two genes were increased after radiation.Next,RNAi technology was used to inhibit the expression of crm-1,a gene whose homologs are associated with motor neuron development in other species.Downregulation of crm-1 expression effectively alleviated the deleterious effects of ionizing radiation on head thrashes and touch avoidance.It was also found that the expression level of crm-1 was regulated by the nuclear receptor gene nhr-76.The results of this study suggest that knocking down the expression level of nhr-76 can reduce the expression level of crm-1,while down-regulating the expression level of crm-1 can alleviate behavioral disorders induced by ionizing radiation.Therefore,inhibition of crm-1 may be of interest as a potential therapeutic target for ionizing radiation-induced neurological dysfunction.

E®ect of laser acupuncture combined with electrical stimulation on recovery from exercise fatigue in mice

In sports events,the rapid recovery after high-intensity training or sport competition performance is very important for athletes'performance and health.The aim of this study is to evaluate the effect of laser acupuncture and electrical stimulation on the recovery from exercise fatigue,using mice with swimming fatigue as experimental model and the electromyography(EMG)and the Raman spectroscopy of blood as evaluation indicators.Root mean square(RMS)and mean power frequency(MPF)of EMG were analyzed after laser acupuncture and electrical stimulation.The amplitude frequency combined analysis(JASA)showed that the proportion of muscles in the fatigue recovery area of the control group,the laser acupuncture group,the multi-channel laser acupuncture group and the laser combined with electrical stimulation group were 34.78%,39.13%,39.13%and 43.48%,respectively.Raman spectroscopy of the mice blood during fatigue recovery showed there is a significant difference between the multi-channel laser acupuncture group and the laser combined with electric stimulation group compared with the recovery period and fatigue period(P<0:05)at the peak of 997 cm^(-1) and the laser combined electrical stimulation group had a statistical difference in the recovery period compared with the fatigue period(P<0.05)at the peak of 1561 cm^(-1).The results showed that laser acupuncture combined with electrical stimulation was beneficial to fatigue recovery in mice,and had the potential value in sports fatigue recovery.

Potential regulatory effects of stem cell exosomes on inflammatory response in ischemic stroke treatment

The high incidence and disability rates of stroke pose a heavy burden on society.Inflammation is a significant pathological reaction that occurs after an ischemic stroke.Currently,therapeutic methods,except for intravenous thrombolysis and vascular thrombectomy,have limited time windows.Mesenchymal stem cells(MSCs)can migrate,differentiate,and inhibit inflammatory immune responses.Exosomes(Exos),which are secretory vesicles,have the characteristics of the cells from which they are derived,making them attractive targets for research in recent years.MSC-derived exosomes can attenuate the inflammatory response caused by cerebral stroke by modulating damage-associated molecular patterns.In this review,research on the inflammatory response mechanisms associated with Exos therapy after an ischemic injury is discussed to provide a new approach to clinical treatment.

Multiomics reveal human umbilical cord mesenchymal stem cells improving acute lung injury via the lung-gut axis

BACKGROUND Acute lung injury(ALI)and its final severe stage,acute respiratory distress syndrome,are associated with high morbidity and mortality rates in patients due to the lack of effective specific treatments.Gut microbiota homeostasis,including that in ALI,is important for human health.Evidence suggests that the gut microbiota improves lung injury through the lung-gut axis.Human umbilical cord mesenchymal cells(HUC-MSCs)have attractive prospects for ALI treatment.This study hypothesized that HUC-MSCs improve ALI via the lung-gut microflora.AIM To explore the effects of HUC-MSCs on lipopolysaccharide(LPS)-induced ALI in mice and the involvement of the lung-gut axis in this process.METHODS C57BL/6 mice were randomly divided into four groups(18 rats per group):Sham,sham+HUC-MSCs,LPS,and LPS+HUC-MSCs.ALI was induced in mice by intraperitoneal injections of LPS(10 mg/kg).After 6 h,mice were intervened with 0.5 mL phosphate buffered saline(PBS)containing 1×10^(6) HUC-MSCs by intraperitoneal injections.For the negative control,100 mL 0.9%NaCl and 0.5 mL PBS were used.Bronchoalveolar lavage fluid(BALF)was obtained from anesthetized mice,and their blood,lungs,ileum,and feces were obtained by an aseptic technique following CO_(2) euthanasia.Wright’s staining,enzyme-linked immunosorbent assay,hematoxylin-eosin staining,Evans blue dye leakage assay,immunohistochemistry,fluorescence in situ hybridization,western blot,16S rDNA sequencing,and non-targeted metabolomics were used to observe the effect of HUC-MSCs on ALI mice,and the involvement of the lung-gut axis in this process was explored.One-way analysis of variance with post-hoc Tukey’s test,independent-sample Student’s t-test,Wilcoxon rank-sum test,and Pearson correlation analysis were used for statistical analyses.RESULTS HUC-MSCs were observed to improve pulmonary edema and lung and ileal injury,and decrease mononuclear cell and neutrophil counts,protein concentrations in BALF and inflammatory cytokine levels in the serum,lung,and ileum of ALI mice.Especially,HUC-MSCs decreased Evans blue concentration and Toll-like receptor 4,myeloid differentiation factor 88,p-nuclear factor kappa-B(NF-κB)/NF-κB,and p-inhibitorαof NF-κB(p-IκBα)/IκBαexpression levels in the lung,and raised the pulmonary vascular endothelial-cadherin,zonula occludens-1(ZO-1),and occludin levels and ileal ZO-1,claudin-1,and occludin expression levels.HUC-MSCs improved gut and BALF microbial homeostases.The number of pathogenic bacteria decreased in the BALF of ALI mice treated with HUCMSCs.Concurrently,the abundances of Oscillospira and Coprococcus in the feces of HUS-MSC-treated ALI mice were significantly increased.In addition,Lactobacillus,Bacteroides,and unidentified_Rikenellaceae genera appeared in both feces and BALF.Moreover,this study performed metabolomic analysis on the lung tissue and identified five upregulated metabolites and 11 downregulated metabolites in the LPS+MSC group compared to the LPS group,which were related to the purine metabolism and the taste transduction signaling pathways.Therefore,an intrinsic link between lung metabolite levels and BALF flora homeostasis was established.CONCLUSION This study suggests that HUM-MSCs attenuate ALI by redefining the gut and lung microbiota.

就诊的独生子女家庭及二胎家庭家长焦虑状况及其影响因素分析

目的:通过分析就诊的独生子女家庭及二胎家庭养育过程中引发家长焦虑状况的各种因素,揭示相关的社会问题,为缓解现代家长的育儿焦虑提供部分理论基础。方法:于2021年11~12月在湖北省武汉市第一医院儿科门诊及云南省昆明市昆明医科大学附属延安医院儿科门诊就诊的儿童及家长,自愿在线完整填写自制问卷的714例一胎、二胎儿童的家庭为研究对象,采用GAD-7广泛性焦虑量表对家长的焦虑状况进行调查研究,并分析影响独生子女家庭及二胎家庭家长焦虑状况的各种因素。结果:714例完整填写问卷的家长焦虑发生率为13.17%(94/714);单因素分析显示,地域、家庭年收入、养育态度、出生后住院情况是独生子女及二胎家庭家长产生焦虑的共同影响因素;多因素Logistic回归分析显示,地域差异、家庭年收入较低、儿童出生后住过院是独生子女及二胎家庭家长焦虑的影响因素(P<0.05)。结论:现代社会中独生子女家庭及二胎家庭养育子女过程中家长易产生焦虑,多种因素与家长产生养育焦虑相关,在独生子女家庭中更为突出,应采取针对性干预措施,缓解家长焦虑,进而提高家庭生活质量,促进儿童健康成长。

Semantic and spatial‐spectral feature fusion transformer network for the classification of hyperspectral image

Recently,transformer‐based networks have been introduced for the classification of hyperspectral image(HSI).Although transformer‐based methods can well capture spectral sequence information,their ability to fuse different types of information contained in HSI is still insufficient.To exploit rich spectral,spatial and semantic information in HSI,a novel semantic and spatial‐spectral feature fusion transformer(S3FFT)network is proposed in this study.In the proposed S3FFT method,spatial attention and efficient channel attention(ECA)modules are employed for the extraction of shallow spatialspectral features.Then,a transformer‐based module is designed to extract advanced fused features and to produce the pseudo‐label and class probability of each pixel for semantic feature extraction.Finally,the semantic,spatial and spectral features are combined by the transformer for classification.Compared with traditional deep learning methods and recently transformer‐based methods,the proposed S3FFT shows relatively better results on three HSI datasets.

Cryo-EM structure of cannabinoid receptor CB1-β-arrestincomplex

Dear Editor,G protein-coupled receptors(GPCRs)play a vital role in regulating almost every aspect of human physiology,making up more than one-third of marketed drug targets(Santos et al.,2017).GPCRs orchestrate their signalling through interactions with three distinct downstream protein families:G proteins,G protein-coupled receptor kinases(GRKs),and arrestins(Santos et al.,2017).While G protein-mediated signalling is initiated upon GPCR stimulation,activated GPCRs return to their basal levels through a GRK-and arrestin-regulated desensitization process(Santos et al.,2017).In addition to modulating receptor desensitization,β-arrestin also regulates downstream events that are distinct from classical G protein signalling(Ahn et al.,2020).

激光虹膜成形术联合YAG激光与传统小梁切除术治疗闭角型青光眼的疗效比较

目的:探讨激光虹膜成形术联合YAG激光治疗青光眼与传统小梁切除术治疗青光眼的临床效果。方法:回顾性分析60例60眼闭角型青光眼患者临床资料,行激光虹膜成形术联合YAG激光虹膜切开术者纳入观察组(38例38眼),行传统小梁切除术者纳入对照组(22例22眼)。比较术前和术后1、3、12mo时,两组患者眼压(intraocular pressure,IOP)、房角开放距离(angle open distance,AOD500)、中央前房深度(anterior chamber depth,ACD)、角膜内皮细胞密度(corneal endothelial cell density,ECD)变化,分析术后12mo内两组患者并发症发生情况。结果:术后1、3、12mo时,两组患者IOP水平均较术前有显著下降,且观察组明显低于同期对照组(P<0.05);观察组患者AOD500、ACD水平均较治疗前有显著提升,且明显高于同期对照组(P<0.05);观察组患者ECD水平与术前比较均无统计学意义(P>0.05),但明显高于同期对照组(P<0.05)。术后12mo内,观察组患者并发症总发生率明显低于对照组(P<0.05)。结论:激光虹膜成形术联合YAG激光治疗青光眼可获得较为理想的治疗效果,其安全性较传统小梁切除术更佳,有利于患者预后眼功能恢复。

构建组织工程人工角膜的天然生物材料的研究进展

当角膜失去透明性或者形状发生改变时,可能会造成视力的丧失。最有效的治疗手段是使用全层或者部分层供体角膜进行角膜移植手术。然而,在全球范围内捐赠角膜的来源严重不足,约有超过98.5%的角膜盲患者在等待捐赠角膜。此外,在角膜移植后,存在感染的可能以及异体移植免疫排斥反应等问题。因此,多年以来组织工程角膜作为供体角膜的可行替代品,不同材料和方法已被广泛研究。并且在近十几年来,有了突破性的进展。研究的最终目的是为了构建具有良好透明性、生物相容性以及合适机械强度的组织工程全层或部分层人工角膜,以修复、再生或替换病变角膜。本综述讨论了近年来最常被研究的天然生物材料包括羊膜、脱细胞角膜、胶原、蚕丝,作为人工角膜支架的研究进展以及目前存在的问题。并进一步说明了该领域中上述讨论的生物材料所面临的其他挑战,以及今后的研究方向。

Amorphous magnetic semiconductors with Curie temperatures above room temperature

Recently, amorphous magnetic semiconductors as a new family of magnetic semiconductors have been developed by oxidizing ferromagnetic amorphous metals/alloys. Intriguingly, tuning the relative atomic ratios of Co and Fe in a Co-Fe-Ta-B-O system leads to the formation of an intrinsic magnetic semiconductor. Starting from high Curie-temperature amorphous ferromagnets, these amorphous magnetic semiconductors show Curie temperatures well above room temperature. Among them, one typical example is a p-type Co28.6Fe12.4Ta4.3B8.7O46 magnetic semiconductor, which has an optical bandgap of ~2.4 eV, roomtemperature saturation magnetization of ~433 emu/cm3, and the Curie temperature above 600 K. The amorphous Co28.6Fe12.4Ta4.3B8.7O46 magnetic semiconductor can be integrated with n-type Si to form p-n heterojunctions with a threshold voltage of ~1.6 V, validating its p-type semiconducting character. Furthermore, the demonstration of electric field control of its room-temperature ferromagnetism reflects the interplay between the electricity and ferromagnetism in this material. It is suggested that the carrier density, ferromagnetism and conduction type of an intrinsic magnetic semiconductor are controllable by means of an electric field effect. These findings may pave a new way to realize magnetic semiconductor-based spintronic devices that work at room temperature.

Role of ranulas in early diagnosis of Sjögren’s syndrome: A case report

BACKGROUND Although the presentations of Sjögren’s syndrome(SS)are variable,ranging from mild dryness to wider systemic involvement,ranulas as early clinical signs were scarcely reported.Here,we present an adult patient with SS,who developed a unilateral simple ranula and was diagnosed primary SS 3 years later.We also provide a review of cases of SS and ranulas from 1980 to 2020.CASE SUMMARY A 22-year-old girl was found to have a left painless floor-of-mouth lesion 3 years ago,without obvious trauma or inducement.The diagnosis of a unilateral(left)simple ranula was made,and the ranula was surgically treated.Within 3 years after the ranula surgery,she developed acute lymphadenectasis in unilateral parotid twice without inducement,and ultrasonic examination revealed diffuse lesions in bilateral parotids and submandibular glands,which strongly suggested SS.Serologic tests and the unstimulated whole saliva flow rate confirmed the SS diagnosis.CONCLUSION Our study underlines that ranulas are early clinical signs of SS.As early diagnosis and early intervention of SS are important to obtain better outcomes,our findings underline the need for histopathological test after sublingual adenectomy and imaging detection of exocrine glands for the patients with ranulas.

Tislelizumab-related enteritis successfully treated with adalimumab:A case report

BACKGROUND With programmed death-1(PD-1) inhibitors becoming the standard treatment for lung cancer,PD-1-related adverse reactions and treatment have gradually become prominent.CASE SUMMARY First reported case of tislelizumab-related enteritis successfully treated with adalimumab 40mg every 2 wk for 3 times in an advanced lung cancer patient who received first-line tislelizumab/pemetrexed/carboplatin for 4 cycles.The patient continued receiving the treatment of pemetrexed/carboplatin after symptoms,abdominal computed tomography and colonoscopy improved,significant diarrhea was not occurred.CONCLUSION Adalimumab can be an effective treatment option for patients with PD-1 antibody related enteritis if they do not respond well to glucocorticoid treatment.

基于3DCS的毫米波雷达安装角度偏差分析方法

偏差分析方法分为一维尺寸链和三维尺寸链分析,其中通过三维软件仿真分析能够实现空间多维度的尺寸链模拟计算,如三维角度偏差仿真分析。文章针对ADAS前毫米波雷达安装基准面角度偏差要求,基于3DCS分析软件,采用蒙特卡洛模拟法,对雷达安装面偏差建模分析,通过仿真分析结果确定设计结构及相关链环的公差定义是否合理,并进行优化设计。

基于3DCS的双横臂空气悬架定位参数仿真和关键尺寸识别方法

四轮定位参数对底盘综合性能非常关键,参数角度受实物制造过程偏差影响,因此尺寸工程需要在前期设计阶段进行角度偏差校核。定位参数角度偏差通过2D尺寸链计算比较复杂,准确率低,文章通过使用3DCS软件,介绍某车型双横臂空气悬架系统模型的定位参数仿真分析及识别建立关键尺寸的方法。