Two-dimensional dumbbell silicene as a promising anode material for(Li/Na/K)-ion batteries

Rechargeable ion batteries require anode materials with excellent performance,presenting a key challenge for researchers.This paper explores the potential of using two-dimensional dumbbell silicene as an anode material for alkali metal ion batteries through density functional theory(DFT)calculations.Our findings demonstrate that alkali metal ions have negative adsorption energies on dumbbell silicene,and the energy barriers for Li/Na/K ion diffusion are as low as0.032 e V/0.055 e V/0.21 e V,indicating that metal ions can easily diffuse across the entire surface of dumbbell silicene.Additionally,the average open circuit voltages of dumbbell silicene as anode for Li-ion,Na-ion,and K-ion batteries are 0.42 V,0.41 V,and 0.60 V,respectively,with corresponding storage capacities of 716 m Ah/g,622 m Ah/g,and 716 m Ah/g.These results suggest that dumbbell silicene is an ideal anode material for Li-ion,Na-ion,and K-ion batteries,with high capacity,low open circuit voltage,and high ion diffusion kinetics.Moreover,our calculations show that the theoretical capacities obtained using DFT-D2 are higher than those obtained using DFT-D3,providing a valuable reference for subsequent theoretical calculations.

Bilateral and symmetric C1-C2 dumbbell ganglioneuromas associated with neurofibromatosis type 1: A case report

BACKGROUND Ganglioneuroma(GN) is a rare and benign tumor that originates from autonomic nervous system ganglion cells. The most frequently involved sites are the posterior mediastinum, the abdominal cavity, and the retroperitoneal space. It rarely occurs in the cervical area, compressing the spinal cord. Neurofibromatosis type 1(NF-1) is an autosomal dominant inheritance disorder, whose prevalence rate approximates one per 3000.CASE SUMMARY We report an extremely rare case of bilateral and symmetric dumbbell GNs of the cervical spine with NF-1. A 27-year-old man with NF-1 presented with a one-year history of gradually progressive right upper extremity weakness and numbness in both hands. Magnetic resonance imaging showed bilateral and symmetric dumbbell lesions at the C1-C2 levels compressing the spinal cord. We performed total resection of bilateral tumors, and the postoperative histopathological diagnosis of the resected mass was GN. After operation, the preoperative symptoms were gradually relieved without complications. To our knowledge,this is the sixth report of cervical bilateral dumbbell GNs.CONCLUSION In some cases, cervical bilateral dumbbell GNs could be associated with NF-1.The exact diagnosis cannot be obtained before operation, and pathological outcome is the current gold standard. Surgical resection is the most effective option, and disease outcome is generally good after treatment.

Bone and soft tissue tumors presenting as sciatic notch dumbbell masses: A critical differential diagnosis of sciatica

AIM To study the clinical findings and characteristic features in sciatic notch dumbbell tumors(SNDTs).METHODS We retrospectively reviewed the clinical outcomes and characteristic features of consecutive cases of SNDTs(n = 8). RESULTS Buttock masses occurred in three patients with SNDT(37.5%). Severe buttock tenderness and pain at rest were observed in seven patients with SNDTs(87.5%). Remarkably, none of the patients with SNDTs experienced back pain. Mean tumor size was 8.4 ± 2.0 cm(range, 3.9 to 10.6 cm) and part of the tumor mass was detected in 2 patients in the sagittal view of lumbar magnetic resonance imaging(MRI).CONCLUSION The clinical information regarding to SNDTs is scarce. The authors consider that above mentioned characteristic findings may facilitate the suspicion of pelvic pathology and a search for SNDT by MRI or computed tomography should be considered in patients presenting with sciatica without evidence of spinal diseases.

Technical Innovation of Electrostimulation Biofeedback Combined with Vaginal Dumbbell in the Treatment of Postpartum Pelvic Floor Dysfunction

Objective: To investigate the application value of electrostimulation biofeedback therapy in combination with vaginal dumbbell therapy to postpartum pelvic floor dysfunction. Methods: Retrospective analysis of 200 cases of postpartum pelvic floor dysfunction patients discharged from the hospital from January 2016 to March 2019 as study subjects who were excluded other underlying diseases and were randomly divided into two groups of 100 cases per group, using electrostimulation biofeedback therapy combined vaginal dumbbell therapy as a treatment group. The treatment of electrostimulation biofeedback therapy in combination with kegel was treated as a control group. Then the curative effects of the two groups were compared and statistically analyzed. Results: There was no significant difference in EMG value of postpartum pelvic floor treatment, type I muscle strength, type II muscle strength, muscle type I fatigue, type II fatigue and POP-Q detection results between the two groups before treatment, p > 0.05. There were significant differences in type I muscle strength, type II muscle strength and muscle type I fatigue between the pelvic floor muscles and the muscles at the end of the treatment day, the sixth month and one year after treatment, p ?There was no statistically significant difference at?the end of muscle type II fatigue?treatment day, p > 0.05;while after the treatment of six months and one year, the difference was statistically significant, p 0.05. In addition, the treatment group and the control group were compared before and after treatment, the difference of myoelectric potential value, pelvic floor muscle type I muscle strength, type II muscle strength, muscle type I fatigue degree, type II fatigue degree and POP-Q test result were significant, and the changes in the indicators before and after treatment in the treatment group were significantly higher than the control group. Comparison of urinary incontinence between the two groups before and after treatment, the difference between pre-treatment and the end of treatment day was not statistically significant, p > 0.05;there was significant difference between half a year and one year after treatment (p 0.05, respectively). Comparing?the satisfaction with sexual life after the time of treatment day, half a year and one year after the end of treatment, the difference was statistically significant (p ?Conclusion: Electrical stimulation biofeedback therapy combined with vaginal dumbbell therapy has a good effect in the treatment of postpartum pelvic floor dysfunction, and it is worthy of popularization and application.

The Synthesis of a New Dumbbell-shaped Compound of Bis-4,4'-bipyridine Bridged by 2,2'-Bipyridine

The title compound 5 was synthesized in 45% yield by the reaction of compound 3 with a, a-bis (bromomethyl)-2, 2-bipyridine in CH3CN at 70℃ for 24 h.

Controllable synthesis of Au-TiO2 nanodumbbell photocatalysts with spatial redox region

Photocatalytic water splitting has increasingly attracted attention as one of the most useful methods of converting solar energy into chemical fuel.However,the undesirable reverse reaction significantly limits the enhancement of efficiency.Herein,we fabricated an Au nanorods/TiO2 nanodumbbells structure photocatalyst(Au NRs/TiO2 NDs)via a facile synthetic strategy,which has spatially separated oxidation and reduction reaction zones.Owing to the unique structure,the charge separation of these photocatalysts can be significantly improved and the reverse reaction can be efficiently inhibited.The photogenerated electrons were injected from the TiO2 to the Au NRs,and a positively charged TiO2 region and negatively charged Au region were formed under UV irradiation.An enhanced hydrogen production performance was obtained compared with that seen in normal Au-TiO2 heterostructure.Under optimized conditions,the H2-production rate can reach up to 60,264μmol/g/h,about six times higher than previously reported Au/TiO2 photocatalysts.Besides this,our work also demonstrates the key factors of precise synthesis of the Au NRs/TiO2 NDs structure,which provides a new perspective and experience for the design of similar catalysts.

Lattice Boltzmann simulations of a dumbbell moving in a Poiseuille flow

In this paper, the lattice Boltzmann method is applied to simulate a dumbbell moving in a pressure-driven flow in a planar channel with the stress-integration method for the evaluation of hydrodynamic force acting on the cylinders. The simulation results show that the dumbbell also has the important feature of the Segr^-Silberberg effect like a particle in a Poiseuille flow. The dumbbell trajectories, orientations, the cylinders vertical velocities and angular velocities all reach their equilibrium values separately independent of their initial positions. It is also found that the dumbbell equilibrium positions depend on the flow Reynolds number, blockage ratio and elastic coefficient. This study is expected to be helpful to understand the dynamics of polymer solutions, polymer synthesis and reaction, etc.

A Rare Case of Cervical Dumbbell Meningioma with the C2 Spinous Process Preservation

Dumbbell growth is often observed in schwannoma but rarely in meningioma. In particular, the occurrence of dumbbell meningioma at the cervical cord level in Japan is markedly rare. We reported an elderly case with symptomatic meningioma that developed in a dumbbell shape from cervical spine and was treated successfully by surgery.

An Improved Parameters Extraction Method for Dumbbell-Shaped Defected Ground Structure

The paper presents an improved equivalent circuit parameters extraction method for the dumbbell-shaped defected ground structure (DGS). The new extraction parameters equations are obtained in closed-form expressions, which contain S11 and S21. The DGS unit with center frequency of 5 GHz is designed and fabricated on a TLX substrate with thickness of 1 mm and dielectric constant of 2.55. The circuit simulated results are in good agreement with the measured results. This parameters extraction method can be widely used for the design and analysis of DGS .

The surgical strategy of upper cervical dumbbell tumors

Objective To investigate the surgical strategy and prognosis of upper cervical dumbbell tumors.Methods From January 2001 to December 2009,46 consecutive cases with upper cervical dumbbell tumor were retrospec-tively studied on

多学科协作手术治疗颈静脉孔区颅内外沟通型肿瘤的临床分析

目的总结分析多学科协作手术切除颈静脉孔区哑铃型肿瘤的临床疗效。方法回顾性分析2011年4月—2023年7月重庆医科大学附属第一医院神经外科后颅底脑干组收治的5例多学科协作手术治疗的颈静脉孔区颅内外沟通型肿瘤患者的临床资料。采集信息包括一般情况、临床表现、专科检查、辅助检查、手术方法、术后并发症、病理及随访结果。结果所有病例均由神经外科、耳鼻咽喉科、颌面外科行MDT讨论并采用MDT手术治疗方案,其中2例行颞下窝Fisch A型联合颈部入路,3例行颅颈联合入路。5例患者中次全切除4例,部分切除1例。术后病理结果提示脑膜瘤2例,神经鞘瘤1例,副神经节瘤1例,脊索瘤1例。术后后组颅神经损伤3例,面瘫3例,听力下降2例,脑脊液漏2例,颅内感染3例。平均随访时间51.8个月(8~150个月);平均随访卡氏功能状态评分(KPS)90分(80~100分)。结论多学科协作手术不仅增加了颈静脉孔区哑铃型肿瘤的切除程度,而且提高了颈静脉孔区哑铃型肿瘤的手术安全性。当全切除较为困难或可能导致较为严重的并发症时,次全切除后辅助放疗也是一种较好的治疗方案。

基于PCA-XGBoost算法的哑铃状SIR差分滤波器设计

随着多业务无线通信技术的发展,具有共模抑制能力的差分带通滤波器越来越受到人们的关注,但是设计差分微带滤波器的传统方法过程复杂且耗时较长。针对这些问题,结合非线性赋权的极限梯度提升(eXtreme Gradient Boosting,XGBoost)算法,通过训练和学习滤波器结构参数和相应频率响应S参数的关系辅助进行滤波器的设计,设计了一款基于改进阶跃阻抗谐振器(Stepped Impedance Resonator,SIR)的哑铃状差分带通滤波器。该滤波器的中心频率为2.6 GHz,相对带宽为7.3%,通带内插入损耗优于0.95 dB,回波损耗优于20 dB,通带内共模抑制优于42 dB,并且具有较宽的阻带。实物测试结果与算法预测结果的一致性,验证了PCA-XGBoost算法(Principal Component Analysis,PCA)用于滤波器辅助设计的可行性。

两类加权哑铃网络的一致性分析

网络的一致性是复杂网络科学的一个重要分支,其研究结果可以为理解网络的动力学行为提供理论依据。网络拓扑结构对网络一致性的鲁棒性有重要影响。文章首先根据经典的哑铃网络模型,分配边的权重,建立了符合实际应用的加权网络模型,其次结合网络一致性、图论等理论推导出加权网络的一阶和二阶一致性指标的具体解析式,进一步使用MATLAB软件数值模拟出两类哑铃网络的一致性指标对网络规模及耦合强度的依赖关系。研究结果表明,耦合强度的增大会使网络一致性增强,且节点全连接的哑铃网络具有更优的一阶与二阶一致性的鲁棒性。

糖尿病哑铃健身操对早期糖尿病肾病治疗效果及炎症因子的影响

目的:探讨糖尿病哑铃健身操对早期糖尿病肾病的治疗效果以及对炎症因子的调控作用,为早期糖尿病肾病患者制定合理的运动治疗模式提供参考。方法:选取2022年1月至2022年12月在盱眙人民医院内分泌科收治的早期糖尿病肾病患者,按照入选标准选取60例患者,根据SAS 9.4软件生成的随机数字表,分为照组和试验组,各30例。对照组接受常规治疗,试验组在常规治疗的基础上进行糖尿病哑铃健身操锻炼。治疗6个月后,比较两组糖脂代谢指标、肾功能指标和炎症因子水平。结果:对照组和试验组治疗后的血糖、血脂、肾功能指标均低于治疗前(P<0.05),且试验组降低更显著(P<0.05)。两组患者治疗后的白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)及单核细胞趋化蛋白-1(MCP-1)水平均显著低于治疗前(P<0.05),且试验组降低更显著(P<0.05)。结论:糖尿病哑铃健身操应用于早期糖尿病肾病患者的治疗中,有助于改善患者的血糖、血脂和肾功能,并能进一步下调炎症因子水平,疗效显著,值得临床推广。

基于DGS的紧凑型低通滤波器

文中提出一种基于缺陷地结构的新型低通滤波器。其由位于微带结构顶部的加宽微带线、位于接地层中的经典哑铃型缺陷地结构(DGS)和蛇形缝隙缺陷地结构(DGS)组成,结构设计紧凑,容易调整。文中选用0.01 dB等波纹的切比雪夫型低通滤波器,分别采用哑铃型DGS、蛇形缝隙DGS替换LPF原型电路中的电感,加宽微带线替换并联电容,同时将加宽微带线产生的寄生电感考虑进去。哑铃型DGS产生的高频衰减点加宽阻带,蛇形缝隙DGS提供的低频衰减点使得通带到阻带陡峭过渡。实验结果表明,所设计的截止频率为2.54 GHz的低通滤波器具有明显的截止频率响应,通带内插损均在0.9dB以下,阻带抑制均在21dB以下。经实物加工测试验证,所设计的低通滤波器实际结果与仿真结果基本一致,具有可行性。

阴道哑铃结合热敏灸、Kegel运动训练治疗产后盆底功能障碍的效果

目的分析阴道哑铃结合热敏灸、Kegel运动训练治疗产后盆底功能障碍(PFD)的效果。方法选择2021年1月至2023年12月诊治的PFD初产妇118例,依照随机抽签法分为观察组和对照组,每组59例。对照组采用阴道哑铃结合Kegel运动训练,观察组给予阴道哑铃结合热敏灸、Kegel运动训练。比较2组治疗效果,干预前后阴道收缩力、盆底肌力、盆底功能、女性性功能指数、尿失禁分级情况。结果观察组总有效率[98.31%(58/59)]高于对照组[84.75%(50/59)](P<0.05)。干预后,观察组阴道收缩力相关指标、盆底肌力、性功能指数均高于对照组(P<0.01);干预后,观察组盆底功能相关评分低于对照组(P<0.01);干预后,观察组尿失禁分级优于对照组(P<0.05)。结论PFD患者经阴道哑铃结合热敏灸、Kegel运动训练干预盆底肌力、盆底功能、尿失禁分级得到了改善,女性性功能指数、阴道收缩力得到了提升,效果较好。

论环境保护地役权构造中的“需役地”

环境保护地役权的需役地“虚化”,导致供役地拼接临近意义上的需役地块实体范畴消失,却可在行政划定的“自然保护地”辖区整体范畴上,以环境生态保护整体价值的形式重聚,由此形成对自然保护地辖区范围内各地块与资源要素(供役地)财产权利中的生产经营与生活价值的制衡手段,从而与传统民法中地役权构造形成基础性技术通约。这有利于形成适应保护地核心保护区向一般控制区保护目的渐变调整,以及相应保护方法中私法与公法保护手段衔接协同与配比变化的方案。

清至民国黄淮地区中产缺失与社会衰变

在中国皇朝时代,清代的“盛世”持续时间最长,清代君主的执政能力也被誉超越前代。历史上,黄淮之间的豫、鲁、皖、苏长期是中国政治核心区及文化最繁荣地区,但清代以后,这里却成为盗匪渊薮,根源就在于皇权的独大及官权的寻租。有权者极易上升为富贵的顶层,无权者基本上沦为贫困的底层,从而消灭了社会稳定的基本力量中产阶层。通过权力寻租造就的社会上层是国家破坏性的力量,使传统体制更加不公正;底层民众为了对抗不公的体制,要么趋向于“江湖”式的拉帮结会,要么体现为搏命式的“剽疾轻死”。即便民国开启共和法治之路,由于中产的缺乏,作为既得利益者的上层群体非常容易地对新政、新法进行狙击和破坏,使共和政制被抹黑并背上恶名,民众并不知道谁是自己真正的利益代言人,无以摆脱对传统上层的依赖。

胸腰交界椎旁巨大哑铃形肿瘤的手术策略

目的明确胸腰交界椎旁巨大哑铃形肿瘤定义,建立其临床分型,并根据术前临床分型选择胸腰交界椎旁巨大哑铃形肿瘤手术治疗策略。方法回顾性分析2018年1月—2023年1月南部战区总医院收治的11例胸腰交界椎旁巨大哑铃形肿瘤患者。根据肿瘤与胸腰椎相对解剖位置的关系,将横向最远端距脊柱后正中线距离≥6 cm的肿瘤定义为胸腰交界椎旁巨大哑铃形肿瘤,并制定新的临床分型,即椎旁型(肿瘤未超过椎体前缘)和椎前型(肿瘤超过椎体前缘)。对椎旁型采用后路肿瘤切除术,对椎前型行后路联合前路肿瘤切除术。术后1周、3个月、6个月、12个月及每年行X线、CT及MRI检查,评价肿瘤切除情况、是否复发及脊柱稳定性、内固定情况;定期随访并评估术后疼痛改善情况。结果椎旁型8例,5例行后路肿瘤切除术+内固定术,3例行后路肿瘤切除术。椎前型3例,2例行后路+前路肿瘤切除术,1例行后路+前路肿瘤切除术+内固定术。术前与术后JOA及VAS评分差异有统计学意义(分别为P=0.03;P<0.001)。术后组织病理学确诊为神经鞘瘤9例,神经纤维瘤2例。11例均获随访。随访时间6个月~2年。所有患者术后复查均未见肿瘤复发,神经症状均明显改善,胸腰背部无酸痛感,内固定无松动、断裂。结论肿瘤横向最远端距脊柱后正中线距离≥6 cm为胸腰交界椎旁巨大哑铃形肿瘤,可分为椎旁型和椎前型。椎旁型采用单纯后路肿瘤切除术即可实现满意切除;椎前型宜采用后路联合前路肿瘤切除术方能实现满意切除。

论房屋建筑结构设计优化措施中的优化技术

随着中国经济快速发展,人们对房屋建筑要求日益升高,房屋建筑结构的优化便成了当下建筑设计行业的重要任务。房屋建筑设计需以安全性、适用性、美观性为基础,因此在房屋结构设计过程中,须采用科学有效的设计方法以及先进的设计技术等,以此来确保房屋结构设计的实用性与科学性。但目前我国部分房屋建筑结构设计依旧存在安全水平不规范,设计水平参差不齐,局部细节处理不完善等问题,因此本文针对目前现状问题进行措施分析,提升结构的整体性能,并对未来房屋建筑行业的发展进行了展望。