Designing Symmetric Gradient Honeycomb Structures with Carbon‑Coated Iron‑Based Composites for High‑Efficiency Microwave Absorption

The impedance matching of absorbers is a vital factor affecting their microwave absorption(MA)properties.In this work,we controllably synthesized Material of Institute Lavoisier 88C(MIL-88C)with varying aspect ratios(AR)as a precursor by regulating oil bath conditions,followed by one-step thermal decomposition to obtain carbon-coated iron-based composites.Modifying the precursor MIL-88C(Fe)preparation conditions,such as the molar ratio between metal ions and organic ligands(M/O),oil bath temperature,and oil bath time,influenced the phases,graphitization degree,and AR of the derivatives,enabling low filler loading,achieving well-matched impedance,and ensuring outstanding MA properties.The MOF-derivatives 2(MD_(2))/polyvinylidene Difluoride(PVDF),MD_(3)/PVDF,and MD4/PVDF absorbers all exhibited excellent MA properties with optimal filler loadings below 20 wt%and as low as 5 wt%.The MD_(2)/PVDF(5 wt%)achieved a maximum effective absorption bandwidth(EAB)of 5.52 GHz(1.90 mm).The MD_(3)/PVDF(10 wt%)possessed a minimum reflection loss(RL_(min))value of−67.4 at 12.56 GHz(2.13 mm).A symmetric gradient honeycomb structure(SGHS)was constructed utilizing the high-frequency structure simulator(HFSS)to further extend the EAB,achieving an EAB of 14.6 GHz and a RL_(min) of−59.0 dB.This research offers a viable inspiration to creating structures or materials with high-efficiency MA properties.

基于1D-Concatenate的信道估计DNN模型优化方法

为提高DNN模型在无线通信中信道估计精度,提出一种基于1D-Concatenate的信道估计DNN模型优化方法。该方法将Concatenate进行一维(1D)数据转换,以跳跃连接的方式引入DNN模型,抑制梯度消失问题,运用1D-Concatenate恢复网络训练过程中丢失的数据特征,提高DNN信道估计精度。为验证优化方法的有效性,选取较典型的基于DNN的无线通信信道估计模型进行对比仿真实验。实验结果表明,本文提出的优化方法对已有DNN模型的估计增益提升可达77.10%,在高信噪比下信道增益提升可达3 dB。该优化方法能有效提高DNN模型在无线通信中的信道估计精度,特别是高信噪比下提升效果显著。

Cortactin Overexpression Correlates with Poor Prognosis in Hepatocellular Carcinoma

Objective： To investigate cortactin expression in hepatocellular carcinoma （HCC） and explore its significance in the prognosis of HCC patients. Methods： Immunohistochemistry was performed for paraffin samples of 119 pairs of HCC tissues （HCCs） and paratumorous liver tissues （PTLTs） to evaluate cortactin expression. The cortactin expression difference in HCCs and PTLTs were analyzed by the McNemar＇s test. The relationship of cortactin expressions in HCCs and clinicopathologic factors was analyzed with Mann-Whitney U test. The Kaplan-Meier method and log-rank test were employed to compare the overall survival between Cortactin negative expression group, weak expression group and strong expression group. Expression of cortactin was further determined in 19 pairs of fresh HCCs and PTLTs specimens with Western blotting. Results： Cortactin expression rate was significantly higher in HCCs （53/119, 44.5%） than that in PTLTs （2/119, 1.7%） （P〈0.001）. The upregulated cortactin expression in HCCs was significantly correlated to absence of capsule formation （P=0.012）, vascular invasion （P=0.037） and high Edmondson-Steiner grade （P=0.020）, and predicted shorter overall survival. Western blotting demonstrated that cortactin expression was upregulated in 9 out of 19 HCCs （47.4%） compared to corresponding PTLTs. Conclusion： Cortactin expression is upregulated in HCC and is related to shorter overall survival of patients, suggesting that cortactin might play roles in the metastasis of HCC and predict a poor prognosis of HCC patients.

Effect of captopril or verapamil on intracellular sodium in cultured vascular smooth muscle cells

The effects of captopril (Cap) and verapamil (Ver)alone and in combination on intracellular Na+ concentration ([Na+]i) in cultured aortic smooth muscle cells (ASMC) of rabbits was evaluated by a direct measurement of [Na+]i with fluorescent dye sodium-binding benzofuran isophthalate (SBFI) combined with digital image. [Na+]i in resting cells was found to be 11.9 ± 0. 7 mmol/L. Angiotensin II (Ang-II, 0.1-10μmol/L) induced an increase of [Na+]i in concentration-dependent manner. Ver (0.1-10μmol/L) inhibited Ang-II (1 μmol/L)-induced increase in [Na+]i, while Cap enhanced Ang-II-induced increase in [Na+]i at 10μmol/L but not at 0.1-1μmol/L. Ver (0.1-1μmol/L)abolished enhancement of Ang-II-induced increase in [Na+]i by Cap. Thus, the inhibition of Capenhanced [Na+]i by Ver may provide a new hypothesis for the underlying molecular mechanism of synergistic effect of the combination of Ca2+ antagonists and angiotensinconverting enzyme inhibitors in controlling blood pressure.

Study on Cellulase Gene Expressed in Pichia pastoris and Analyses of Its Biochemical Characters

Objectives: In order to increase cellulose degradation, cellulase was expressed in this study. Literature Review: Cellulose is the most abundant organic carbon source on Earth;its enzymatic hydrolysis will be very useful for bioenergy production and resource recycling. Methods: Cellobiohydrlase I (CBH I) gene was amplified from genomic DNA of Trichoderma koningii and inserted into pGAPZα A plasmid to construct the vector of pGAPZαA-CBH I. It was linearized and transformed into Pichia pastoris by electroporation. The recombinant Pichia pastoris was selected and incubated with YPD medium for cellulase secretion. Results: The result showed that CMCase and avicelase activity in the supernatant was 1.1798 U/mL and 0.1276 U/mL, the molecular weight of the expressed protein was 53 kDa determined with SDS-PAGE analyses, and the optimal temperature and pH of the expressed cellulase were 45?C - 50?C and 4.5 - 5.0, respectively. Conclusion: Cellulase gene from T. koningii has been successfully cloned and expressed in Pichia pastoris.

Possible Metformin-Induced Toe Nails Disorder

The aim of this article was to report a case of toe nails disorder associated with metformin use in an elderly patient with type2diabetes. Two years ago, after receiving metformin 0.5 g three times daily for 6 months, a 60-year-old Chinese man found his ten toe nails gradually thickened and yellowed (especially two thumbs). The symptoms improved and recovered after metformin discontinuance. Half year ago, metformin 0.5 g three times daily adopted again and toe nails disorder occurred again. Physician modified the therapy plan and replaced metformin with acarbose to control blood glucose level of this patient. According to the follow up 3 months after his discharge, ten toe nails recovered significantly and new parts of the nails were normal. Nail disorder was rarely reported in the worldwide, but the physicians should keep awareness of this adverse drug reaction (ADR), proper actions should be taken once it occurred to avoid unnecessary suffering of the patient.

XeO_(3)中与惰性气体键有关的相变和键的对称化

本文采用第一性原理计算研究了压力诱导下的三氧化氙晶体的结构相变.研究发现在压强约2.18 GPa时,发生了由低压P2_(1)2_(1)2_(1)相到高压Pnma相的结构相变,同时伴随体积的急剧减小.对称性化的Xe-O_(2)键使高压相具有更好的结构对称性.相变可能由O原子在惰性气体键Xe-O_(3)...Xe内部由O_(3)跳跃至O_(2)格点和近邻的两个Xe原子沿y方向的相对运动共同引起.电子空域函数分析显示位于Xe原子同侧的三个Xe-O共价键可能是Xe^(6+)出现孤对电子轮廓外形的原因.

Role of ferroptosis in esophageal cancer and corresponding immunotherapy

Esophageal cancer(EC)is one of the most common digestive system malignancies in the world.The combined modality treatment of EC is usually surgery and radiation therapy,however,its clinical efficacy for advanced patients is relatively limited.Ferroptosis,a new type of iron-dependent programmed cell death,is different from apoptosis,necrosis and autophagy.In recent years,many studies have further enlightened that ferroptosis plays an essential role in the occurrence,development and metastasis of tumors.Targeting ferroptosis stimulates a new direction for further exploration of oncologic treatment regimens.Furthermore,ferroptosis has a critical role in the immune microenvironment of tumors.This paper reviews the mechanism of ferroptosis and the ferroptosis research progress in the treatment of EC.We further elaborate the interaction between ferroptosis and immunotherapy,and the related mechanisms of ferroptosis participation in the immunotherapy of EC,so as to provide new directions and ideas for the treatment of EC.

Effects of different pelvic osteotomies on acetabular morphology in developmental dysplasia of hip in children

Developmental dysplasia of hip seriously affects the health of children,and pelvic osteotomy is an important part of surgical treatment.Improving the shape of the acetabulum,preventing or delaying the progression of osteoarthritis is the ultimate goal of pelvic osteotomies.Re-directional osteotomies,reshaping osteotomies and salvage osteotomies are the three most common types of pelvic osteotomy.The influence of different pelvic osteotomy on acetabular morphology is different,and the acetabular morphology after osteotomy is closely related to the prognosis of the patients.But there lacks comparison of acetabular morphology between different pelvic osteotomies,on the basis of retrospective analysis and measurable imaging indicators,this study predicted the acetabular shape after developmental dysplasia of the hip pelvic osteotomy in order to help clinicians make reasonable and correct decisions and improve the planning and performance of pelvic osteotomy.

Simultaneous bottom-up double-layer synergistic engineering by multifunctional natural molecules for efficient and stable SnO2-based planar perovskite solar cells

The performance and stability of perovskite solar cells(PSCs)is limited by detrimental defects,mostly distributed at the grain boundary(GB)of bulk perovskite film and interface,which induce serious carrier non-radiative recombination.Therefore,there is particularly urgent to realize simultaneous passivation of bulk defects and interfacial defects.In this work,a simple,low-cost and effective multifunctional modification strategy is developed by introducing theλ-Carrageenan(λ-C)as the interfacial layer of SnO_(2)/perovskite.The sulfate groups ofλ-C not only play a positive role in passivating the Sn4+from SnO_(2)film,resulting in high conductivity,but also effectively passivate the defects at the SnO_(2)/perovskite interface.Meanwhile,λ-C can effectively passivate the defects in the perovskite film due to the strong binding force between the high content of sulfate groups and PbI2.The synergistic effect ofλ-C simultaneously achieves interfacial defects and bulk defects passivation,better crystalline quality,suppressed charge recombination,released interfacial stress and more favorable interfacial energy level alignment.Based on the above efficient synergy,theλ-C-modified device achieves a high efficiency of 23.81%,which is~24.53%higher than the control device(19.12%).To our best knowledge,23.81%of power conversion efficiency(PCE)is the highest reported PCE value of PSCs employing green natural additives.Moreover,long-term and thermal stabilities are significantly improved after interface modification.Thus,this work provides an idea for developing multifunctional natural materials towards the attainment of the efficient and stable PSCs.

Comparative Analysis of Rice Export Competitiveness in Heilongjiang Province of China Based on Index Method

Based on the analysis of rice planting and export development in Heilongjiang Province in 2013-2021,this paper comprehensively used three export competitiveness analysis methods,namely,trade competitiveness index,revealed comparative advantage(RCA)analysis and international market share analysis,to compare the four major rice exporters in the world and the three major rice export provinces and cities in China.Besides,it evaluated the rice export competitiveness of Heilongjiang Province from multiple perspectives.It analyzed the reasons for low competitiveness in terms of export product structure,export market structure,production and processing technology,and brand building.Finally,it is recommended to clarify the positioning of rice export quality and take more measures to ensure product quality;improve the level of industrialization of rice production and processing,and extend the rice industry chain;develop diversified rice export markets and improve export flexibility;adhere to the principle of"opening the door and going out",expand the international popularity of high-quality brands,so as to enhance the rice export competitiveness of Heilongjiang Province.

The Application of Specific Nursing in Perioperative Patients of Thoracic Surgery and Postoperative Recovery and Improvement of Patients’ Negative Emotions

Objective: To study the application of specific nursing in perioperative patients of thoracic surgery and postoperative recovery and improvement of patients’ negative emotions. Patients and Methods: A total of 88 patients in the thoracic surgery operating room of our hospital were selected and divided into group A (specific nursing, n = 44) and group B (routine nursing, n = 44). The anxiety and depression status of the two groups were assessed by the Self-rating Anxiety Scale (SAS) and the Self-rating Depression Scale (SDS). The relevant respiratory parameters after surgery, including total lung capacity, maximum respiration flow-rate, tidal volume, and vital capacity were observed. The extubation time, ICU hospitalization time, and VAS scores of postoperative pain were compared, with a score of 10 being full. The higher the score, the higher the pain. The in-cidence of postoperative wound infection, pulmonary infection, respiratory tract infection and the satisfaction with the operation were compared. Sf-36 scale was used to score the physical function, life function, psychological function and quality of life of the patients in the two groups. Results: The surgical effect of group A was significantly higher than that of group B (all p < 0.05). The total lung capacity, maximum respiration flow-rate, tidal volume and vital capacity of group A were significantly higher than those of group B (all p < 0.05). The extubation time and hospitalization time of group A were significantly higher than those of group B (all p < 0.05). VAS score of group A was significantly lower than that of group B (all p < 0.05). The infection rate of group A was significantly lower than that in group B (all p < 0.05). Conclusion: Specific nursing has higher application value than routine nursing, which is worth further promotion in clinic.

考虑旅客携行行为的安检系统服务参数优化研究

为提高公共交通安检系统服务效率,考虑旅客“绕行取行李”“等待取行李”的携行行为,分析安检系统服务流程,构建安检系统的Jackson排队网络模型;分析旅客人体安检和行李安检之间的速度差,厘定在携行行为条件下及不同情境中旅客提取行李前的等待时间,并修正安检系统的Jackson排队网络模型;优化安检系统服务参数,实现系统服务设施的最优配置;以某公共客运站为研究对象,进行案例验证分析。结果表明:优化模型不仅能改善安检服务设施配置效率,而且显著降低系统稳态条件下的平均等待队长;增加“绕行取行李”行为的旅客比例能显著降低旅客提取行李前的平均等待时间。

公共空间导视系统的空间视域模型及其眼动验证

为研究公共空间导视系统的空间视域,考虑人口学统计特征,引入垂直视场角、水平视场角和视域比例等空间视域概念,构建导视系统的视觉空间模型。以某公共客运站为研究对象,根据现场调查结果筛选出旅客购票乘车活动的主流线;兼容被试者的自然状态、准确度和精确度,采用眼动追踪技术观察旅客购票乘车过程的视觉行为特征;提取被试者注视、眼跳、瞳孔等眼动特征值,生成聚类树状谱系图。眼动实验结果表明:导视标识在水平视场角5.69°~19.51°、垂直视场角8.42°~25.73°、视域比例0.45~2.38的空间视域范围内的视觉搜索效率高。设计者宜按此范围对导视系统进行规划布置。

MicroRNA-29a对人正常滋养细胞迁移和侵袭功能的影响及其可能的机制

目的检测microRNA-29a(miR-29a)在子痫前期孕妇胎盘组织中的表达及其对人正常滋养细胞系HTR8/Svneo迁移和侵袭能力的影响及可能的作用机制。方法收集行剖宫产分娩的30例子痫前期孕妇及30例正常妊娠孕妇的胎盘组织,应用实时聚合酶链反应(real-time PCR)检测胎盘组织miR-29a的表达水平。应用生物信息学软件预测miR-29a的潜在靶基因,选取ITGB1作为研究靶基因。将miR-29a模拟物(miR-29a mimics)转染人正常滋养细胞系HTR8/Svneo,real-time PCR检测转染后HTR8/Svneo细胞中miR-29a的表达变化,划痕实验和Transwell侵袭实验检测转染后HTR8/Svneo细胞迁移和侵袭能力的变化,Western blot检测转染后HTR8/Svneo细胞ITGB1蛋白的表达变化。结果 real-time PCR结果显示子痫前期孕妇胎盘组织中miR-29a表达水平均较正常妊娠孕妇增高(P<0.05)。人正常滋养细胞系HTR8/Svneo细胞转染miR-29a mimics后,miR-29a表达水平增高(P<0.05),ITGB1蛋白表达水平降低(P<0.05),划痕实验和Transwell侵袭实验显示细胞迁移和侵袭能力降低(P<0.05)。结论 miR-29a在子痫前期孕妇胎盘组织中高表达,可能通过调控ITGB1的表达参与子痫前期的发生发展。

表面增强拉曼光谱在胃癌诊断和分期中的应用

目的探讨表面增强拉曼光谱技术(surface-enhanced Raman spectroscopy,SERS)在胃癌(gastric cancer,GC)诊断中的应用价值,并评估SERS在GC分期中的可行性.方法利用In Via+Plus型激光共焦显微拉曼光谱仪检测63例经病理学确诊GC患者,45例GC前病变患者,50例健康志愿者的血清,分析不同血清SERS光谱的特征,采用单因素方差分析(ANOVA)、独立样本t检验、主成分分析(principal component analysis,PCA)、线性判别分析(linear discriminant analysis,L D A)等统计分析方法进行统计学处理,利用受试样品工作特征曲线(receiver operating characteristic curve,ROC)评价诊断效能.结果 GC、GC前病变、正常组血清的平均SERS光谱存在差异,在725、1099、1133、1589/cm位移处,GC组血清SERS强度高于正常组;在1004、1328、1446、1657/cm位移处,GC前病变组和GC组血清SERS强度均弱于正常组.相比正常组和癌前病变组,GC患者血清在815/cm处有特征峰.在1133、1446、1589/cm位移处,GC TNMⅢ-Ⅳ期患者血清SERS强度明显强于Ⅰ-Ⅱ期;在1004/cm位移处,Ⅰ-Ⅱ期血清SERS谱峰强度则明显强于Ⅲ-Ⅳ期.利用PCA-LDA统计方法得到SERS技术诊断GC的灵敏度、特异性和准确率分别为96.8%(61/63),78%(39/50)和88.5%(100/113);ROC曲线下面积为0.927;SERS技术区分GC TNMⅠ-Ⅱ期和Ⅲ-Ⅳ期的灵敏度、特异性和准确率分别为97.5%(39/40),73.9%(17/23)和88.9%(56/63);ROC曲线下面积为0.857.结论基于表面增强拉曼光谱技术对GC、GC前病变及健康人的血清进行检测和分析,可有效鉴别GC、GC前病变及健康人,并且能够对不同分期的GC做出有效区分,有望成为GC的早期诊断、临床决策指导以及预后评估的新方法.

融合多元用户特征和内容特征的微博谣言实时检测模型

针对目前基于单文本语义特征深度学习的微博谣言实时检测模型泛化能力不足的问题,提出一种融合多元用户特征和内容特征的实时检测模型.首先,在传统用户基本特征和内容统计特征的基础上,利用用户的历史行为数据,挖掘用户理性值和用户专业度两个深层次特征;然后,基于词向量和带有注意力机制的双向GRU神经网络构建文本语义特征学习模型;最后,采用分层特征级联和全连接的方式进行特征融合,把融合特征输入分类模型进行训练.实验结果表明,该模型的检测准确率达到了91.74%,相比其他只关注文本语义特征的深度学习实时检测模型具有更好的识别效果,相比于其他改进型的实时检测模型F1-Measure值也提高了2.19%.

乙肝肝硬化与乙肝肝硬化合并糖尿病患者肠道菌群结构初步探讨

目的研究乙肝肝硬化与乙肝肝硬化合并糖尿病患者肠道菌群结构是否存在差异性.方法收集9例乙肝肝硬化和6例乙肝肝硬化合并糖尿病患者粪便标本,提取粪便DNA,进行PCR扩增(上游引物:5’CCATCTCATCCCTGCGTGTCTCCGACTCA GACACGACTCCTACGGGAGGCAGCAG-3’,下游引物:5’CCTATCCCCTGTGTGCCTTGGCAGTCTC AGACGAGCTGACGACARCCATG-3’)并对产物进行纯化,利用Roche454高通量测序平台对两组患者的粪便菌群16SrDNA的V3-V6区域进行测序及生物信息学分析.结果乙肝肝硬化及乙肝肝硬化合并糖尿病两组间的多样性参数(OTU数、chao1指数、simpson指数、shannon指数)均无统计学差异.后者肠道中的变形菌门明显多于前者(P<0.05),拟杆菌门与厚壁菌门的比例无明显差异;纲的水平上,γ-变形菌纲在后者明显较多(P<0.05),其余纲水平未见差异;目的水平上,后者伯克氏菌目较前者明显增多(P<0.05),而脱硫弧菌目明显减少(P<0.05),其余无统计学差异;科的水平上,韦荣球菌科、产碱菌科在后者的肠道菌群中的比例明显增多(P<0.05),而链球菌科、梭菌科在前者肠道中占优势(P<0.05),其余的在科水平中无统计学差异;属的水平上,Parabacteroides、Roseburia、韦荣氏球菌属、萨特氏菌属在后者的肠道菌群中的比例较多(P<0.05),而Faecalibacterium、链球菌属在前者肠道中更占优势(P<0.05),其余未见明显差异.结论乙肝肝硬化与乙肝肝硬化合并糖尿病患者的肠道菌群结构具有相似性但又存在各自的特异性,某些菌群的差异有可能成为治疗乙肝肝硬化合并糖尿病的新靶点.

上转换纳米粒子的Y(OH)CO3壳层包覆及壳层转化

制备如异质核-壳结构等不同结构的镧系离子掺杂的上转换纳米材料对上转换纳米材料的基本性质研究及应用至关重要。在本工作中,我们采用简单的共沉淀方法在NaGdF4:Yb/Tm上转换纳米粒子表面包覆了无定形的Y(OH)CO3壳层。通过透射电子显微镜,X射线衍射,能量色散X射线荧光光谱等物理表征手段研究了所得纳米粒子的结构和形貌,结果表明Y(OH)CO3壳层可以在300°C附近转化形成YOF,形成异质核-壳结构。同时,初步研究结果显示该方法也可拓展用于其他无定形壳层的包覆及蛋黄-蛋壳结构纳米粒子的制备。这些结果表明这种方法在制备不同结构的上转换纳米材料方面有良好的应用前景。

融合语义相似度的矩阵分解推荐算法

针对矩阵分解推荐算法没有考虑推荐对象本身内涵特征的问题,提出一种融合对象语义相似度的矩阵分解推荐算法。首先利用知识图谱分布式表示学习算法将推荐对象所属领域的语义数据嵌入到一个低维语义向量空间;其次计算对象间语义相似度,把该语义相似度融入矩阵分解的目标优化函数中,从语义视角弥补矩阵分解推荐算法没有考虑推荐对象本身内涵特征的不足。结果表明,该改进算法相比于传统矩阵分解推荐算法具有更高的准确率、召回率和覆盖率。