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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： Chang-Sheng Zuo Kang Wang Li-Zhen sun Ting-Ting sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

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不同学年医学生的心理特点及教育

辽宁医学院学报（社会科学版） 2009年第3期7卷 46-48页

作者：孙晓楠徐州医学院江苏徐州221000

处在不同阶段的医学生有着不同的心理特点。作为思想政治辅导员,应根据医学院校的实际情况作出及时的分析与把握,从而培养出祖国需要的医学人才。对于初年级同学,主要是帮助其适应大学生活;对于中年级同学,主要是引导其不断完善自己,提... 详细信息

处在不同阶段的医学生有着不同的心理特点。作为思想政治辅导员,应根据医学院校的实际情况作出及时的分析与把握,从而培养出祖国需要的医学人才。对于初年级同学,主要是帮助其适应大学生活;对于中年级同学,主要是引导其不断完善自己,提高自主能力与实践能力;而对于实习毕业年级,则应该加强他们的择业就业心理辅导。

关键词：医学生不同阶段心理特点心理教育

Catalyst design and structure control for photocatalytic refineries of cellulosic biomass to fuels and chemicals

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Journal of Energy Chemistry 2024年第7期94卷 102-127页

作者： Lulu sun Nengchao Luo State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Lignocellulosic biomass is the largest renewable hydrocarbon resource on *** cellulose,one of the major components of lignocellulose,powered by solar energy is a promising way of providing lowcarbon-footprint energy chemicals such as H_(2),HCOOH,CO,and transportation ***-of-the-art biorefineries target the full use of biomass feedstocks as they have a maximum collection radius of 75-100 km,requesting efficient and selective photocatalysts that significantly influence the outcome of photocatalytic ***-performed photocatalysts can harvest a broad solar spectrum and are active in breaking the chemical bonds of cellulose,decreasing the capital investments of ***,photocatalysts should control the selectivity of cellulose conversion,originating target products to level down separation *** separation in photocatalysts and interfacial charge transfer between photocatalysts and cellulose affect the activity and selectivity of cellulose refineries to H2 and carbonaceous *** account for the challenges above,this review summarizes photocatalysts for the refineries of cellulose and downstream platform molecules based on the types of products,with the structure features of different types of photocatalysts discussed in relation to the targets of either improving the activity or product *** addition,this review also sheds light on the methods for designing and regulating photocatalyst structures to facilitate photocatalytic refineries of cellulose and platform molecules,meanwhile summarizing proposed future research challenges and opportunities for designing efficient photocatalysts.

关键词： Photocatalysts Biorefineries Cellulose Fuels Hydrogen

Blindness-free beam scanning antenna with array of array architecture: principle,design,and experiment

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Science China(Information Sciences) 2024年第3期67卷 209-224页

作者： Jianxu sun Yujian CHENG School of Electronic Science and Engineering University of Electronic Science and Technology of China

This paper presents a 66–76-GHz sparsely-excited phased array antenna with the array of array(Ao A) architecture for eliminating the blindness and suppressing the grating lobe when scanning. For the array antennas printed on the thick dielectric layers with high relative permittivity, scanning blindness appears and seriously impacts the radiation performance. To address this issue, the Ao A topology is developed first. It finds that the scanning blindness appears due to the coupling of the radiating Floquet modes to the non-radiating surface wave(SW) modes. Therefore, the array is divided into two types of domino *** inner-phase distributions are introduced into the domino subarrays to break the one-to-one relationship between the Floquet mode and the SW mode. Then, the blindness inside ±60° scanning volume is eliminated by the aperiodic subarrays. Meanwhile, the aperiodic inner-phase distributions enhance the aperiodicity of the array and contribute to suppressing the grating lobe when scanning. Next, the meta-surface-based dipole with the shorted post is chosen as the unit cell for the proposed aperiodic array. Based on these methods,the array achieves the wide-scanning performance of ±60° in the E-plane and ±30° in the H-plane, without the blindness and the grating lobe. Finally, the 16×16 array is built and simulated with the dimension of32 mm × 32 mm. At the highest operating frequency, the simulated gains are 28.42, 25.17, and 24.01 d Bi when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. Compared to the ideal gain, it shows that the simulated radiation efficiency is about 84.13%, 62.08%, and 35.23% when scanning to the broadside, 50° in the E-plane, and 30° in the H-plane, respectively. The worst transmission coefficient, i.e., the worst isolation, is-11.97 d B between the central element and its two adjacent elements in the E-plane. The array prototypes are fabricated, and the experiments are carried out to ver

关键词： 6G communication systems phased array AoA aperiodic subarray wideband wide-scanning surface-wave scanning blindness grating lobe

Self-Aligning Multi-Modal Transformer for Oropharyngeal Swab Point Localization

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Tsinghua Science and Technology 2024年第4期29卷 1082-1091页

作者： Tianyu Liu Fuchun sun Department of Computer Science and Technology Tsinghua UniversityBeijing 100083China

The oropharyngeal swabbing is a pre-diagnostic procedure used to test various respiratory diseases, including COVID and Influenza A (H1N1). To improve the testing efficiency of testing, a real-time, accurate, and robust sampling point localization algorithm is needed for robots. However, current solutions rely heavily on visual input, which is not reliable enough for large-scale deployment. The transformer has significantly improved the performance of image-related tasks and challenged the dominance of traditional convolutional neural networks (CNNs) in the image field. Inspired by its success, we propose a novel self-aligning multi-modal transformer (SAMMT) to dynamically attend to different parts of unaligned feature maps, preventing information loss caused by perspective disparity and simplifying overall implementation. Unlike preexisting multi-modal transformers, our attention mechanism works in image space instead of embedding space, rendering the need for the sensor registration process obsolete. To facilitate the multi-modal task, we collected and annotate an oropharynx localization/segmentation dataset by trained medical personnel. This dataset is open-sourced and can be used for future multi-modal research. Our experiments show that our model improves the performance of the localization task by 4.2% compared to the pure visual model, and reduces the pixel-wise error rate of the segmentation task by 16.7% compared to the CNN baseline.

关键词： segmentation localization transformer multi-modal perception robotic perception

基于小波神经网络的航空发动机传感器故障诊断

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机床与液压 2020年第3期48卷 180-186页

作者：白杰张正王伟孙晓楠中国民航大学民航民用航空器适航审定技术重点实验室天津300300

航空发动机传感器故障诊断系统对于保证航空发动机控制系统可靠性和安全性至关重要,针对传统基于发动机模型的传感器故障诊断中存在建模精度不足导致故障诊断存在误诊和漏诊的问题,提出以小波变换和神经网络为基础,使用正常传感器预测... 详细信息

航空发动机传感器故障诊断系统对于保证航空发动机控制系统可靠性和安全性至关重要,针对传统基于发动机模型的传感器故障诊断中存在建模精度不足导致故障诊断存在误诊和漏诊的问题,提出以小波变换和神经网络为基础,使用正常传感器预测故障传感器值。通过对比传感器输出和神经网络预测值的残差来实现传感器的故障诊断,其中神经网络可以在传感器故障后估计出正常的模拟信号代替故障信号供发动机控制系统使用,实现航空发动机控制系统的容错控制;使用改进粒子群优化算法优化BP神经网络的阈值和权值,以提高神经网络诊断和预测信号精度。仿真结果表明:该方法可以有效完成故障诊断,减少漏诊和误诊的发生。

关键词：传感器小波变换神经网络改进粒子群优化算法容错控制

角膜移植术后病毒性角膜内皮炎与内皮型排斥反应的临床特征

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中华实验眼科杂志 2016年第11期34卷 1002-1007页

作者：孙晓楠肖格格冯云裴涌洪晶北京大学第三医院北京大学眼科中心 100191 沈阳市第四人民医院眼科沈阳市第四人民医院眼科 110031

背景角膜移植术后由于糖皮质激素类药物和免疫抑制剂的长期使用而导致眼组织的免疫能力下降,从而引起炎性病变,主要表现为术眼角膜内皮炎症反应,常见有病毒性角膜内皮炎和内皮型排斥反应,二者的临床症状相似,但治疗方法和预后有所不同... 详细信息

背景角膜移植术后由于糖皮质激素类药物和免疫抑制剂的长期使用而导致眼组织的免疫能力下降,从而引起炎性病变,主要表现为术眼角膜内皮炎症反应,常见有病毒性角膜内皮炎和内皮型排斥反应,二者的临床症状相似,但治疗方法和预后有所不同,因此二者的鉴别诊断至关重要,但目前相关研究较少.目的观察和比较角膜移植术后病毒性角膜内皮炎和内皮型移植排斥反应的临床特征,为临床诊断和治疗提供参考依据.方法对2011年1月至2013年9月在北京大学眼科中心接受角膜移植术后发生内皮炎症反应的29例患者的病历资料进行回顾性分析,检查项目包括裂隙灯显微镜检查、激光扫描共焦显微镜检查、病毒血清学检测,并采用Goldmann眼压计测量眼压,根据临床症状将患者分为病毒性角膜内皮炎组17例和内皮型排斥反应组12例,分别行抗病毒药物联合糖皮质激素治疗和局部糖皮质激素联合免疫抑制剂治疗,眼压升高者局部用酒石酸溴莫尼定滴眼液和/或马来酸噻吗心安滴眼液点眼,根据二者的临床表现、检查结果和治疗结果总结2种病变的鉴别点.结果 2个组患者接受的术式均为穿透角膜移植术,组间患者术前不同角膜原发病例数的差异有统计学意义（P=0.000）;内皮型排斥反应组患者眼压为（16.00±3.19） mmHg（l mmHg=0.133 kPa）,明显低于病毒性角膜内皮炎组的（34.00±3.84） mmHg,差异有统计学意义（￡=13.298,P=0.000）;内皮型排斥反应组患者术后发病时间为（21.92±8.60）个月,明显长于病毒性角膜内皮炎组的（14.41±5.79）个月,差异有统计学意义（t=-2.816,P=0.009）;内皮型排斥反应组患者平均年龄为（44.00±16.71）岁,明显小于病毒性角膜内皮炎组的（57.24±12.66）岁,差异有统计学意义（t=2.429,P=0.022）.病毒性角膜内皮炎眼角膜后沉着物（KP）呈色素羊脂状,排列散乱,角膜严重水肿,可累及植片和植床,朗格汉斯巨细胞分布无规律,角膜内皮细胞水肿,治疗后多不能恢复;而内皮型排斥反应组角膜后KP排列规律,角膜内皮层洁净,角膜水肿仅累及植片,朗格汉斯巨细胞分布密集且规律,角膜内皮细胞损害轻微,治疗后可恢复正常.2个组间患者血清lgG水平和性别分布的差异均无统计学意义（均P＞0.05）. 结论角膜移植术后病毒性角膜内皮炎的角膜水肿、KP和炎症反应均重于内皮型排斥反应,且眼压升高主要发生于病毒性角膜内皮炎患者;发病年龄可作为鉴别诊断的重要参考,大于70岁的患者并发病毒性角膜内皮炎的可能性更大;角膜移植术后内皮型排斥反应发生时间晚于病毒性角膜内皮炎,术前角膜原发病对二者的鉴别有重要的参考价值.

关键词：角膜移植角膜内皮/病理穿透角膜移植/不良反应抑制物排斥反应角膜炎/并发症术后并发症角膜内皮炎

同步放化疗和放疗序贯化疗治疗非小细胞肺癌骨转移的临床疗效和安全性

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当代医学 2022年第11期28卷 83-85页

作者：孙晓楠辽宁省朝阳市中心医院肿瘤二科辽宁朝阳122000

目的探讨同步放化疗和放疗序贯化疗治疗非小细胞肺癌骨转移的临床疗效和安全性。方法选取2018年9月至2019年9月本院收治的80例非小细胞肺癌骨转移患者作为研究对象,按照随机抽签法分为对照组与观察组,每组40例,对照组采用放疗序贯化疗治... 详细信息

目的探讨同步放化疗和放疗序贯化疗治疗非小细胞肺癌骨转移的临床疗效和安全性。方法选取2018年9月至2019年9月本院收治的80例非小细胞肺癌骨转移患者作为研究对象,按照随机抽签法分为对照组与观察组,每组40例,对照组采用放疗序贯化疗治疗,观察组采用同步放化疗治疗,比较两组近期疗效、不良反应发生率及生存质量。结果观察组治疗总有效率为62.50%,高于对照组的37.50%,差异有统计学意义(P<0.05)。观察组不良反应发生率为27.50%,对照组不良反应发生率为35.00%,两组比较差异无统计学意义。治疗后,观察组生理功能、心理功能、社会功能、身体机能评分均明显高于对照组,差异有统计学意义(P<0.05)。结论同步化疗方法治疗非小细胞肺癌骨转移患者的近期疗效更佳,两种化疗方式的药物安全性相当,同步放化疗治疗方式在提高患者生存质量方面效果显著,值得临床推广应用。

关键词：非小细胞肺癌骨转移同步放化疗放疗序贯化疗生存质量评分