Synthesis of Co–Fe 1D Nanocone Array Electrodes Using Aluminum Oxide Template

Porous anodic alumina oxide (AAO) obtained via two-step anodization is a material commonly used as a template for fabricating 1D nanostructures. In this work, copper and cobalt-iron 1D nanocones were obtained by an electrodeposition method using AAO templates. The templates were produced using two-step anodization in H₂C₂O₄. The Co–Fe nanostructures are characterized by homogeneous pore distribution. The electrocatalytic activity of the produced nanomaterials was determined in 1 M NaOH using the linear sweep voltammetry (LSV) and chronopotentiometry (CP) methods. These materials can be used as catalysts in the water-splitting reaction. The sample’s active surface area was calculated and compared with bulk materials.     

虚拟现实技术应用于髋部骨折手术仿真的建立*△

背景:髋部骨折的病情较复杂,临床医师选择适当治疗方案和手术入路的主要依据来源于影像学检查,常难以准确判断空间立体关系. 目的:探讨基于64排螺旋 CT 扫描数据对髋部骨折进行虚拟手术设计的可行性和临床应用价值. 方法:将髋部骨折患者.dicom 格式 CT 数据导入 Mimics 软件,进行图像分割,建立骨折三维模型并进行虚拟复位,将.stl 格式复位模型导入 Imageware12.0,根据钢板放置位置选择合适长度钢板,螺钉固定.并快速成型形成实体与导航模板. 结果与结论:重建三维可视模型可准确反映出骨折特点、骨折移位方向和程度,并可进行任意旋转观察,实现了内固定手术模拟.可见术前应用计算机辅助虚拟现实手术设计可以制定合理的个体化手术方案,有很好的临床应用价值.     

基于超分子“印迹模板”理论探讨中药升降浮沉

在前期提出超分子化学对中药四性理论特殊影响的基础上,进一步分析中药升降浮沉的历史沿革、研究概况,并运用超分子印迹模板理论对中药升降浮沉理论进行解析,提出对中药升降浮沉的评价方法。人体与中药均是印迹模板印迹作用的聚集体,在印迹模板作用规律下,不同类型的中药成分与人体的靶点通过锁-钥关系以非共价键结合,中药客体超分子通过键的作用可纠正人体主体超分子在自识别、自组织、自组装、自复制过程时发生的寒热、气机失调。人体具备抵抗外界病邪侵袭的能力,有赖于其气机升降出入的正常;中药具有升降浮沉的性能并能祛除病疾,有赖于其能调整人体气机紊乱,或顺应气机、祛邪外出以增强机体免疫的能力。基于此,在分析中药升降浮沉药理作用的基础上,探究其物质基础,并建立中药升降浮沉的评价方法,通过超分子印迹模板理论对中药升降浮沉进行剖析,揭示其科学内涵,推动中药药性理论不断创新。     

3D打印模板辅助CT引导放射性125I粒子植入治疗肿瘤专家共识

放射性粒子组织间永久植入治疗（简称粒子植入）肿瘤属于近距离范畴,它具有局部剂量高和周围正常组织损伤小的特点,已成为早期前列腺癌标准治疗手段之一。粒子植入借助超声、CT、MRI影像引导将放射性粒子送入到肿瘤靶区,因此,放射性粒子治疗兼具外科和介入治疗的特点。而粒子植入治疗的剂量学评估、危及器官剂量控制又隶属放射治疗范畴,因此,粒子治疗是跨学科、跨专业的技术。建立一支多学科合作团队,才有可能实现精准的粒子植入治疗。目前前列腺癌粒子植入技术已经非常成熟,而其他部位肿瘤粒子植入技术流程、标准尚处于研究阶段。本文主要基于3D打印模板技术建立起的规范和共识,内容包括：粒子物理学、剂量学、技术流程、适应证、不良反应。粒子治疗是非常有效的局部治疗手段,但是鉴于目前尚缺少大规模循证医学证据,还需要多中心的前瞻性、随机Ⅲ期临床研究,以及发表高水平文章,提高循证医学等级,确立粒子植入治疗在肿瘤综合治疗中的地位和作用。     

Accuracy of a computerized tomography-guided template-assisted implant placement system: an in vitro study

Objectives: To evaluate the accuracy of computer-assisted 3D planning and implant insertion using computerized tomography (CT).
Materials and methods: Nine implants were planned on pre-operative CTs of six resin models, which were acquired with radiographic templates, using a planning software (E implants). Each resin model contained three pre-existing control implants (C implants). Radiographic templates were converted into operative guides containing 4.8-mm-diameter titanium sleeves. A single set of insertable sleeves was used for consecutively drilling the six models, followed by implant insertion through the guide sleeves. Models were further divided into group A (the first three models) and group B (the last three models). Post-operative CTs were used to compare implant positions with pre-operative planned positions. Statistical analysis included the Mann–Whitney U test for E and C implants and the Wilcoxon's signed ranks test for groups A and B.
Results: The mean apex depth deviations for E and C implants [0.49 mm±0.36 standard deviation (SD) and 0.32 mm±0.21 SD, respectively], and the mean apex radial deviations (0.63 mm±0.38 SD and 0.49 mm±0.17 SD, respectively) were similar ( P >0.05). The mean angulation deviations for E and C implants were 2.17±1.06°SD and 1.33±0.69°SD, P <0.05. E implant deviations of all the parameters in group A were significantly smaller than E implant deviations in group B.
Conclusions: Computer-assisted implant planning and insertion provides good accuracy. Deviations are mainly related to system and reproducibility errors. Multiple use of drills and titanium sleeves significantly reduces system accuracy.     

Image‐based coronary tracking and beat‐to‐beat motion compensation: Feasibility for improving coronary MR angiography

A method to reduce the effect of motion variability in MRI of the coronary arteries is proposed. It involves acquiring real‐time low‐resolution images in specific orthogonal orientations, extracting coronary motion from these images, and then using this motion information to guide high‐resolution MR image acquisition on a beat‐to‐beat basis. The present study establishes the feasibility and efficacy of the proposed approach using human motion data in an offline implementation, prior to future online implementation on an MRI scanner. To track the coronary arteries in low‐resolution real‐time MR images in an accurate manner, a tracking approach is presented and validated. The tracking algorithm was run on real‐time images acquired at 15–20 frames per second in four‐chamber, short‐axis, and coronal views in five volunteers. The systolic and diastolic periods in the cardiac cycles, computed from the extracted motion information, had significant variability during the short time periods typical of cardiac MRI. It is also demonstrated through simulation analysis using human tracked coronary motion data that accounting for this cardiac variability by adaptively changing the trigger delay for acquisition on a beat‐to‐beat basis improves overall motion compensation and hence MR image quality evaluated in terms of SNR and CNR values. Magn Reson Med 60:604–615, 2008. © 2008 Wiley‐Liss, Inc.     

Porous Ba Ferrite Prepared from Wood Template

Ba ferrite materials with porous microstructures were prepared from a natural cedar wood template in order to investigate new electromagnetic shielding materials. The wood templates were infiltrated with barium nitrate and iron nitrate solutions (molar ratio = 1:12) and dried to form ferrite gel, then, they were sintered in air at a temperature between 800 °C and 1400 °C. The 1-dimensional porous structures were retained after sintering and the pore size was approximately 10–20 μm. These ferrites show large coercive force and anisotropy field. The largest coercive force was obtained for the specimen sintered at 800 °C.     

Chiral recognition of Nα-protected amino acids and derivatives in non-covalently molecularly imprinted polymers

Highly crosslinked synthetic polymers, selective for various N^α-protected amino acids and derivatives, were prepared by non-covalent molecular imprinting. Methacrylic acid and ethylene glycol dimethacrylate were copolymerized in the presence of the print molecules, which were subsequently extracted from the polymers. The recognition of the polymers for the print molecules and molecules of similar structures was investigated by using the polymers as stationary phases in HPLC. The functional groups of the print molecules interact via hydrogen bonds with the positioned carboxyls of the polymer. It was shown that the N^α-protecting group, the C^α-protecting group and the amino acid side chain are also recognized by the binding sites in the polymer. © Munksgaard 1994.