Multi-Objective Optimization of the Ultrasonic Scalpel Rod and Tip with Improved Performance:Vibration Frequency,Amplitude,and Service Life

Ultrasonic scalpel design for minimally invasive surgical procedures is mainly focused on optimizing cutting performance.However,an important issue is the low fatigue life of traditional ultrasonic scalpels,which affects their long-term reliability and effectiveness and creates hidden dangers for surgery.In this study,a multi-objective optimal design for the cutting performance and fatigue life of ultrasonic scalpels was proposed using finite element analysis and fatigue simulation.The optimal design parameters of resonance frequency and amplitude were determined.By setting the transition fillet and keeping the gain structure away from the node position to enable the scalpel to have a high service life with excellent cutting performance.The frequency modulation method of setting the vibration node bosses at the node position and setting the vibration antinode grooves at the antinode position was compared.Then,the mechanism of the influence of various design elements,such as tip,shank,node position,and antinode position,on the resonance frequency,amplitude,and fatigue life of the ultrasonic scalpel was analyzed,and the optimal design principles of the ultrasonic scalpel were obtained.The proposed ultrasonic scalpel design was confirmed by simulations,impedance measurements,and liver tissue cutting experiments,demonstrating its feasibility and enhanced performance.This research introduces innovative design strategies to improve the fatigue life and performance of ultrasonic scalpels to address an important issue in minimally invasive surgery.

6G New Multiple Access Technology

As a basic technology at physical layer of mobile communications,non-orthogonal multiple access has been attracting wide attention across the academia and the industry.During the standardization of the fifth-generation(5G)of mobile communications,3GPP conducted preliminary study on non-orthogonal multiple access without reaching the consensus to standardize the technology.

柚子皮生物炭负载Mg/Al-LDH对废水中U(Ⅵ)的吸附性能研究

采用液相共沉淀法制备了柚子皮生物炭负载镁铝层状双氢氧化物复合材料BC@Mg/Al-LDH,并将其用于废水中U(Ⅵ)的去除。探究了pH、温度、吸附时间、初始质量浓度、干扰离子对BC@Mg/Al-LDH吸附U(Ⅵ)的影响。结果表明,在U(Ⅵ)初始质量浓度为10 mg/L、pH=5、温度为303 K、吸附时间为5 min时,BC@Mg/Al-LDH对U(Ⅵ)的吸附量达到96 mg/g。吸附过程符合准二级动力学模型和Freundlich等温模型。FT-IR和XPS分析发现主要吸附机理为表面羟基络合和层间碳酸盐共沉淀。干扰离子试验表明,Ca^(2+)、Fe^(3+)、Mg^(2+)、Cu^(2+)等对吸附效果无影响。BC@Mg/Al-LDH经5次再生循环利用后吸附率仍可接近80%。

有机化学课程虚拟教研室的建设与实践

提出有机化学课程虚拟教研室的建设目标和建设内容,通过36校联动,分组分层次推进有机化学课程虚拟教研室建设,并开展相关教研活动。系统阐明有机化学课程虚拟教研室的组织形式和机制建设。总结有机化学课程虚拟教研室建设以来的一系列跨校教研活动。重点论述有机化学课程虚拟教研室在教学资源建设方面的进展。通过发挥各成员学校教师在教学、科研上的特色和优势,推动互联互通、共建共享型有机化学课程虚拟教研室建设,实现协同教研新形态。

基于虚拟教研室平台的有机化学课程知识图谱建设探索

依托有机化学课程虚拟教研室优质资源,建设钉钉平台的有机化学课程知识图谱。知识图谱包含由知识单元、知识点等“节点”的层级结构、通过“节点”间的“关系”形成的网状结构,将课程内容前后紧密的联系起来。通过融入虚拟教研室共建共享的教学资源,知识图谱可为有机化学课程的教学活动和人才培养提供全方位的支持。

Effect of soaking time of dithionite-citrate-bicarbonate solution on strength and deformation characteristics of lateritic soil

This study aimed to reveal the influence of different free-iron-oxides contents on the strength and deformation characteristics of in situ lateritic soil.A test method that combined the selective chemical dissolution method and in situ Ménard pressuremeter test(PMT)was proposed.The soaking time in dithioniteecitrateebicarbonate(DCB)solution was used as a variable to control the free-iron-oxides content in lateritic soil.Then,the in situ lateritic soil boreholes with different soaking time were tested by PMT.The results showed that the in situ horizontal pressure p0,critical edge pressure pf,ultimate pressure prediction pl,pressuremeter modulus Em,shear modulus Gm,and foundation-bearing capacity f0k of lateritic soil decreased rapidly after immersing in DCB solution within 1e4 d.With increasing soaking time,the decrease rate reduced gradually.Moreover,the relationship curve between free-iron-oxides content and soaking time declined rapidly and then stabilized,and the free-iron-oxides content at the inflection point was 30.11 g/kg.When the free-iron-oxides content changed to the inflection point,the free-iron-oxides that played a cementing role was largely removed,indicating that the effective cementing iron-content of Miaoling lateritic soil was about 52.9%.This study demonstrated that the proposed test method can determine the influence of free-iron-oxides content on the strength and deformation characteristics of lateritic soil.

Experimental Investigation of Material Removal in Elliptical Vibration Cutting of Cortical Bone

To benefit tissue removal and postoperative rehabilitation,increased efficiency and accuracy and reduced operating force are strongly required in the osteotomy.A novel elliptical vibration cutting(EVC)has been introduced for bone cutting compared with conventional cutting(CC)in this paper.With the assistance of high-speed microscope imaging and the dynamometer,the material removals of cortical bone and their cutting forces from two cutting regimes were recorded and analysed comprehensively,which clearly demonstrated the chip morphology improvement and the average cutting force reduction in the EVC process.It also revealed that the elliptical vibration of the cutting tool could promote fracture propagation along the shear direction.These new findings will be of important theoretical and practical values to apply the innovative EVC process to the surgical procedures of the osteotomy.

聚羟基铝柱撑蛭石对废水中Sb(Ⅲ)的去除性能研究

采用铝的多聚物Al_(30)对蛭石进行柱撑制备聚羟基铝柱撑蛭石(Al-VMT),考察初始pH、Al-VMT投加量、时间、温度等因素对去除Sb(Ⅲ)的影响。利用扫描电子显微镜、能谱仪、X射线衍射、X射线光电子能谱仪和傅里叶红外光谱仪对材料进行表征。该吸附过程符合拟二级动力学和颗粒内扩散模型,Langmuir和Freundlich吸附等温线模型均能很好地描述Al-VMT对Sb(Ⅲ)的吸附行为。结果表明,通过酸预处理以及聚羟基铝柱撑成功对蛭石进行了改性;Al-VMT对Sb(Ⅲ)的吸附机理主要包括静电吸附以及与羟基(—OH)的配位络合等;经过4次吸附-解吸循环后,Sb(Ⅲ)去除率仍达80%以上。

Ambipolar performance improvement of the C-shaped pocket TFET with dual metal gate and gate–drain underlap

Dual-metal gate and gate–drain underlap designs are introduced to reduce the ambipolar current of the device based on the C-shaped pocket TFET(CSP-TFET).The effects of gate work function and gate–drain underlap length on the DC characteristics and analog/RF performance of CSP-TFET devices,such as the on-state current(I_(on)),ambipolar current(I_(amb)),transconductance(g_(m)),cut-off frequency(f_(T))and gain–bandwidth product(GBP),are analyzed and compared in this work.Also,a combination of both the dual-metal gate and gate–drain underlap designs has been proposed for the C-shaped pocket dual metal underlap TFET(CSP-DMUN-TFET),which contains a C-shaped pocket area that significantly increases the on-state current of the device;this combination design substantially reduces the ambipolar current.The results show that the CSP-DMUN-TFET demonstrates an excellent performance,including high I_(on)(9.03×10^(-4)A/μm),high I_(on)/I_(off)(~10^(11)),low SS_(avg)(~13 mV/dec),and low I_(amb)(2.15×10^(-17)A/μm).The CSP-DMUN-TFET has the capability to fully suppress ambipolar currents while maintaining high on-state currents,making it a potential replacement in the next generation of semiconductor devices.

Biochanin A,as the Lrg1/TGF-β/Smad2 pathway blockade,attenuates blood-brain barrier damage after cerebral ischemiareperfusion by modulating leukocyte migration patterns

Background:Biochanin A is an excellent dietary isoflavone that has the concomitant function of both medicine and foodstuff.The attenuation function of biochanin A on blood-brain barrier(BBB)damage induced by cerebral ischemia-reperfusion remains unclear.Methods:C57BL/6 mice were subjected to 1 h middle cerebral artery occlusion(MCAO)followed by 24 h reperfusion.The infarct volume of the brain was stained by TTC,while leakage of the brain was quantitatively stained by Evans blue,and the neurologic deficit score was measured.Microglial-induced morphologic changes were observed via immunofluorescence staining,and rolling and adhering leukocytes in venules were observed via two-photon imaging,while the inner fluorescein isothiocyanate-albumin of venules were compared with those of surrounding interstitial area through venular albumin leakage.Results:The attenuation effect of biochanin A on tight junction injury was compared in ischemia-reperfusion mice or conventional knockdown of leucine-richα2-glycoprotein 1(Lrg1)mice.Biochanin A could ameliorate BBB injury in mice with cerebral ischemiareperfusion in a dose-dependent manner by strengthening the immunostaining volume of occludin,claudin-5,and zonula occludens-1.The amoeba morphologic changes of microglial combined with the elevated expression of Lrg1 could be relieved under the treatment of biochanin A.Biochanin A played a countervailing role on the rolling leukocytes in the vessel,while the leakage of blood vessels was reduced.Biochanin A diminished its functions to further improved attenuation for tight junction injury on conventional Lrg1-knockout mice,as well as the inhibition effects on TGF-β1,and the phosphorylation of suppressor of mothers against decapentaplegic 2(Smad2)/Smad2 via western blot assay.Conclusion:Biochanin A could alleviate tight junction injury induced by cerebral ischemiareperfusion and blocked the Lrg1/TGF-β/Smad2 pathway to modulate leukocyte migration patterns.

有效构建中小学思想政治教育资源共建共享机制

思想政治教育资源共建共享是深化中小学思政教育改革的必要举措。有效构建中小学思政教育资源共建共享机制,应当契合中小学思想政治教育课程改革的政策精神,以保障课程改革效果为目标导向,搭建中小学内部、中小学之间、中小学与社会之间思想政治教育资源的共建共享平台,在教学过程中推进思政资源融合应用,实现思政资源成果的转化,使中小学思想政治教育水平迈上新台阶。

HDGF、VEGF与肝肿瘤组织MVD水平的关系及对肝癌病人预后的影响

目的:探讨肝癌组织中肝癌衍生生长因子(HDGF)、血管内皮生长因子(VEGF)的表达及与肿瘤组织微血管密度(MVD)、病人远期预后的关系。方法:选取94例肝癌术后病理标本,距离肿瘤病灶边缘2 cm以上的癌旁组进行研究,采用免疫组织化学法检测肿瘤标本、癌旁组织的HDGF、VEGF及MVD情况。结果:肝癌组织中HDGF蛋白、VEGF蛋白阳性表达率分别为62.77%、65.96%,均明显高于癌旁组织的15.96%、19.15%(P<0.01);肝癌组织中MVD明显高于癌旁组织(P<0.01);肝癌组织中HDGF、VEGF蛋白表达与MVD计数均呈明显正相关关系(r=0.824,r=0.839,P<0.01);HDGF蛋白阳性表达病人3年生存率19.61%(10/51),明显低于阴性表达生存率47.06%(16/34)(P<0.01)。VEGF蛋白阳性表达病人3年生存率14.81%(8/54),明显低于阴性表达生存率56.25%(18/32)(P<0.01)。结论:肝癌组织中HDGF、VEGF的表达升高,并且与肝组织MVD呈正相关性,HDGF、VEGF的阳性表达对病人的远期预后不利。

应用基因芯片筛选HBV对肝癌细胞脂代谢相关基因影响的初步研究

目的通过基因芯片技术探测HBV感染对肝癌细胞脂代谢相关基因表达的影响,为深入研究HBV在肝癌脂代谢中的作用及机制提供新的依据。方法本研究以HepG2细胞作为对照,用稳定表达HBV的肝癌细胞HepG2.2.15来模拟HBV感染的肝癌细胞,利用基因芯片对肝癌细胞HepG2和HepG2.2.15进行分析,筛选出脂代谢相关的差异表达基因,对差异基因参与的信号传导通路进行分析。RT-PCR检测显著差异表达基因CYP1A1、CYP1B1和AHR。结果基因芯片共筛选出肝癌细胞HepG2和HepG2.2.15中差异表达基因共1263个,其中涉及脂代谢的基因有92个,具有表达上调的基因53个,表达下调的基因39个,涉及细胞生长、增殖、分化、运动和耐药等多种分子功能。RT-PCR检测脂代谢差异表达基因,其结果与芯片结果一致,确定芯片检测结果可靠。结论应用人类表达芯片成功筛选出HBV转染的人肝癌细胞后的脂代谢相关差异表达基因,为HBV感染在肝癌中的作用提供线索。

氨肟化法己内酰胺生产废水处理技术研究及应用现状

氨肟化法己内酰胺生产废水成分复杂,处理难度较大,已成为我国己内酰胺生产领域的研究热点。综述了氨肟化法己内酰胺生产废水的预处理技术、生化处理技术和深度处理技术,以及各类组合处理技术的研究和应用现状,指出己内酰胺生产废水处理工程化技术的开发,不仅要考虑到工艺技术的有效性,也要考虑到运行成本等因素,设计出抗冲击能力强、运行效率高、处理成本低、自动化程度高的己内酰胺生产废水处理系统是今后的发展方向。

AFP对裸鼠肝癌移植瘤生长的促进作用及对血管形成相关因子的影响

目的:探讨AFP对肝癌移植瘤生长及血管生成调节因子表达的影响。方法:采用pEGFP-N1-AFP和pEGFP-N1质粒分别转染SMMC-7721细胞构建SMMC-7721/AFP和SMMC-7721/CON细胞,将裸鼠分为实验组和对照组,分别于裸鼠皮下接种SMMC-7721/AFP和SMMC-7721/CON,从而建立人肝癌移植瘤模型,动态观测裸鼠肿瘤体积和质量变化;取肿瘤组织用实时定量RT-PCR和Western blot检测组织中的HOXA7、eIF4E、VEGFA和FGF2表达。结果:构建SMMC-7721/AFP和SMMC-7721/CON细胞,并将其接种到裸鼠皮下成功建立肝癌移植瘤模型。与对照组比较,实验组移植瘤体积与质量显著增高,成瘤后第12天,实验组移植瘤体积和质量分别为(307.71±47.63)mm 3和(20.243±0.411)g,差异均具有显著性(P=0.012,P=0.04)。实时定量RT-PCR结果显示AFP过表达提高了肝癌移植瘤细胞HOXA7、eIF4E和FGF2 mRNA表达水平,分别为2.488±1.155、23.828±2.465和4.407±1.164,与对照组相比增高程度具有显著性差异,但VEGFA mRNA表达未见显著增强。Western blot结果显示:SMMC-7721/AFP较SMMC-7721/CON细胞显著提高HOXA7蛋白表达水平,但对FGF2和VEGFA无显著影响。结论:AFP基因转染可明显促进裸鼠肝癌移植瘤的生长,该作用可能与其促进肿瘤血管形成因子在mRNA水平的调控有关。

消癌平对肝癌细胞HepG2差异表达基因及可变剪接的影响

目的通过RNA-seq分析消癌平作用前后肝癌细胞HepG2的差异表达基因(differentially expressed genes,DEG)及可变剪接(alternative splicing,AS)。方法本研究以HepG2细胞作为对照组,以质量浓度为40 mg/L消癌平作用24 h后的肝癌细胞为实验组,利用Illumina HiSeq平台对实验组和对照组进行分析,使用PossionDis方法进行DEG检测,使用rMATS软件检测不同样品间的AS和差异剪接基因(differentially spliced genes,DSG),并利用基因本体(gene ontology,GO)对其功能进行分类及富集分析。结果与对照组比较,消癌平作用后共得到DEG 608个,其中上调基因147个,下调基因461个。对照组发生AS 21387个,消癌平使HepG2 AS减少到19265个,且两组均以外显子(SE)跳跃最多而内含子(RI)保留最少为主。对差异表达的AS行GO富集分析,提示其中生物过程相关的22个,细胞成分相关13个,分子功能相关的有8个。结论消癌平诱导HepG2产生的大量DEG及AS在抑制肝癌生长增殖过程中发挥作用。

新型除氟吸附材料的研究进展

半导体、稀土开采等行业所排放的氟废水所引发氟中毒现象备受关注。吸附法是去除废水中氟离子的有效方法之一,但传统吸附剂存在吸附容量低、选择性差等缺点,亟需研发具有高吸附容量、可再生且无二次污染的吸附材料。本文归纳了一些新型吸附材料,如高分子材料吸附剂、生物炭、层状双氢氧化物、工业废弃物、纳米材料及其改性材料在含氟废水中的研究应用;总结了这些改性材料的制备过程,介绍了这些材料吸附除氟的能力,分析了新型吸附材料吸附除氟的机理以及共存离子干扰、pH适用范围等影响因素,并指出了材料制备存在的问题,提出了制备对氟离子具有高选择性能的改性吸附材料的发展方向和材料循环利用所需解决的重要问题。

Effects of physical properties on electrical conductivity of compacted lateritic soil

Natural soils of various types have different electrical properties due to the composition,structure,water content,and temperature.In order to investigate the electrical properties of lateritic soil,electrical conductivity experiments have been conducted on a self-developed testing device.Test results show that the electrical conductivity of laterite increases with the increase of water content,degree of saturation and dry density.When the water content is below the optimum water content,the electrical conductivity of soils increases nonlinearly and the variation rate increases dramatically.However,when the water content,degree of saturation,or dry density increases to a certain value,the electrical conductivity tends to be a constant.In addition,soil electrical conductivity increases with the increase of temperature,and it is observed that the electrical conductivity decreases with the increase of the number of wetting–drying cycles.

Validation of the six-and-twelve criteria among patients with hepatocellular carcinoma and performance score 1 receiving transarterial chemoembolization

BACKGROUND Transarterial chemoembolization(TACE)is recommended for patients with intermediate hepatocellular carcinoma(HCC)according to treatment guidelines.However,a large number of patients with advanced HCC also receive TACE in clinical practice,especially for those with liver-confined HCC and Eastern Cooperative Oncology Group score(ECOG)1.In view of previous studies,such patients have different prognoses from advanced HCC patients with macrovascular invasion or extrahepatic spread;therefore,patients with ECOG 1 alone might be classified into the intermediate stage and benefit from TACE treatment,but a study particularly focusing on such patients and exploring the effectiveness of TACE therapy is lacking.AIM To investigate treatment outcomes of TACE in HCC patients with ECOG 1 alone and propose a specific prognostic model.METHODS Patients from 24 Chinese tertiary hospitals were selected in this nationwide multicenter observational study from January 2010 to May 2016.Overall survival(OS)was estimated using Kaplan–Meier curves and compared by the log-rank test.Multivariate Cox regression was used to develop the potential prognostic models.The discriminatory ability of the models was compared and validated in various patient subgroups.The individual survival prediction for six-and-twelve(6&12)criteria,defined as the algebraic sum of tumor size(cm)and tumor number,was illustrated by contour plot of 3-year survival probability and nomogram.RESULTS A total of 792 eligible patients were included.During follow-up,median OS reached 18.9 mo[95%confidence interval(CI):16.9-21.0].Three independent multivariate analyses demonstrated that tumor size,tumor number,α-fetoprotein level,albumin–bilirubin grade and total bilirubin were prognostic factors of OS(P<0.05).The previously proposed 6&12 criteria was comparable or even better than currently proposed with the highest predictive ability.In addition,the 6&12 criteria was correlated with OS in various subgroups of patients.The patients were stratified into three strata with score≤6,>6 but≤12,and>12 with different median OS of 39.8 mo(95%CI:23.9-55.7),21.1 mo(95%CI:18.4-23.8)and 9.8 mo(95%CI:8.3-11.3),respectively(P<0.001).CONCLUSION TACE is effective for advanced HCC patients with ECOG 1 alone,and the 6&12 criteria may help with clinical decision-making.

Clinical Impact of t(14;18) in Diffuse Large B-cell Lymphoma

Objective： Recent studies have suggested that t（14;18） is present in a significant proportion of diffuse large B-cell lymphomas （DLBCLs）. However, the prognostic significance of this translocation and its relationship with BCL-2 protein expression remains controversial. Our study aimed to investigate the predictive power of t（14;18） and BCL-2 protein expression in the prognosis of DLBCLs. Methods： Biopsy specimens from 106 DLBCLs were analyzed using interphase fluorescence in situ hybridization （FISH）. Immunophenotypic analysis of CD20, CD3, CD10, BCL-6, MUM1 and BCL-2 was performed by immunohistochemistry. SPSS 13.0 software was used for statistical analysis. Results： The t（14;18） was identified in 27 of 106 cases （25.5%）. The percentages of tumor cells expressing CD10, BCL-6, MUM1 and BCL-2 were 21.7%, 26.4%, 56.6% and 73.6%, respectively. The presence of this translocation was significantly correlated with the expression of CD10 and immunophenotypic subtype （p0.001）. No association was observed between BCL-2 protein expression and the presence of t（14;18）. Multivariate analysis confirmed that both t（14;18） and BCL-2 expression were significantly associated with survival. Moreover, patients with t（14;18） had worse prognosis, compared with those with BCL-2 expression （for overall survival： hazard ratio, 4.235; 95%CI, 2.153-8.329, p0.001 vs. hazard ration, 2.743; 95%CI, 1.262-5.962, p=0.011）. Conclusions： The t（14;18） is a useful prognostic tool for the evaluation of DLBCL immunophenotype and prognosis. The prognosis of GCB （germinal centre-like B cell） DLBCL patients should be made with the consideration of the presence of this translocation, and the detection of t（14;18） should be included as a routine diagnostic test in these cases.