检索结果-南通市图书馆

Pediatric CT of the Lung: Influences on Image Quality

Open Journal of Radiology 2013年第1期3卷 45-50页

作者： Enno Stranzinger Sebastian Tobias Schindera Jennifer Larissa Cullmann Ralph Herrmann shu-fang hsu schmitz Rainer Wolf Department of Diagnostic Interventional and Pediatric Radiology Bern University Hospital Bern Switzerland Institute of Mathematical Statistics and Actuarial Science University of Bern Bern Switzerland

Objective: To assess influential factors of CT on image quality of the lung in children. Materials and methods: Retrospective evaluation of 82 consecutive chest-CT-scans in 50 children (1-16 years, 17 females and 33 males). Two pediatric radiologists evaluated in consensus the subjective image quality on lung windows using a 4-point scale (1 = very good, 2 = good, 3 = moderate, 4 = poor). Ventilation, motion artifacts and beam hardening artifact were included in this score. The effects of the following factors were evaluated: 1) CT-settings (tube energy, tube current);2) Patient’s age, weight, chest size, ventilation;3) Artifacts of devices, tubes and lines;4) Combination MRI of the abdomen prior to CT of the chest with the same sedation/anesthesia in oncological patients. Results: The odds of having a better image quality increase with patient’s age, weight and chest diameter in a multiple-factor model. There was no difference between tube current protocols. In infants (15 kg) subjective image quality was good in only 1 (8%), moderate in 8 (67%) and poor in 3 (25%) scans. In childhood and adolescence (15 - 90 kg) 25 (36%) scans were very good, 28 (40%) good, 15 (21%) moderate and 2 (3%) poor. Artifacts of tubes and lines have no statistical significant influence on image quality. Lower lung densities were related to better ventilation and older children. Conclusion: Increasing dose parameters may not increase necessarily subjective image quality in infants (15 kg), rather than good ventilation, optimal preparation and avoiding artifacts. A possible explanation of the rather moderate image quality in infants may be the alveolar stage of the lung. Up to two years of age the lung has a high specific lung volume per kg and a low total lung volume with a low alveolar surface.

关键词： CT Lung Image Quality Children

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Adaptive Algorithms on Maximizing Monotone Nonsubmodular Functions

引用

Journal of the Operations Research Society of China 2024年第2期12卷 428-445页

作者： Bin Liu Hui Su shu-fang Gong Qi-Zhi fang School of Mathematical Sciences Ocean Universityof ChinaQingdao266100ShandongChina

Submodular optimization is widely used in large *** order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in *** general,the function values are given by a value oracle,but in practice,the oracle queries may consume a lot of ***,how to strike a balance between optimizing them is *** this paper,we focus on maximizing a normalized and strictly monotone set function with the diminishing-return ratio under a cardinality constraint,and propose two algorithms to deal with *** apply the adaptive sequencing technique to devise the first algorithm,whose approximation ratio is arbitrarily close to 1-e^(-γ)in O(logn·log(log k/γ)) adaptive rounds,and requires O(logn^(2)·log(log k/γ)) *** by adding preprocessing and parameter estimation steps to the first algorithm,we get the second *** second algorithm trades a small sacrifice in adaptive complexity for a significant improvement in query *** the same approximation and adaptive complexity,the query complexity is improved *** the best of our knowledge,this is the first paper of designing adaptive algorithms for maximizing a monotone function using the diminishing-return ratio.

关键词： Approximation algorithm Adaptivity Nonsubmodular maximization Cardinality constraint

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Design and Implementation of Nonlinear Precoding for MIMO-SDMA Toward 6G Wireless

引用

China Communications 2024年第1期21卷 69-87页

作者： Chaowu Wu Yue Xiao shu fang Gang Wu National Key Laboratory of Wireless Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we present a novel and robust nonlinear precoding(NLP)design and detection structure specifically tailored for multiple-input multipleoutput space division multiple access(MIMO-SDMA)systems toward 6G *** approach aims to effectively mitigate the impact of imperfect channel estimation by leveraging the channel fluctuation mean square error(MSE)for reconstructing a highly accurate precoding matrix at the ***,we introduce a simplified receiver structure that eliminates the need for equalization,resulting in reduced interference and notable enhancements in overall system *** conduct both computer simulations and experimental tests to validate the efficacy of our proposed *** results reveals that the proposed NLP scheme offers significant performance improvements,making it particularly well-suited for the forthcoming 6G wireless.

关键词： MIMO-SDMA nonlinear precoding Tomlinson-Harashima precoding(THP) vector perturbation(VP)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reconceptualization of immune checkpoint inhibitor-associated gastritis

引用

World Journal of Gastroenterology 2024年第36期30卷 4031-4035页

作者： Ying-fang Deng Xian-shu Cui Liang Wang Department of Oncology Affiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina Department of Gastrointestinal Oncology Surgery Affiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina

In recent years,with the extensive application of immunotherapy in clinical practice,it has achieved encouraging therapeutic *** enhancing clinical efficacy,however,it can also cause autoimmune damage,triggering immunerelated adverse events(irAEs).Reports of immunotherapy-induced gastritis have been increasing annually,but due to its atypical clinical symptoms,early diagnosis poses a certain ***,it can lead to severe complications such as gastric bleeding,elevating the risk of adverse outcomes for solid tumor patients if immunotherapy is ***,gaining a thorough understanding of the pathogenesis,clinical manifestations,diagnostic criteria,and treatment of immune-related gastritis is of utmost importance for early identification,diagnosis,and ***,the treatment of immune-related gastritis should be personalized according to the specific condition of each *** patients with grade 2-3 irAEs,restarting immune checkpoint inhibitors(ICIs)therapy may be considered when symptoms subside to grade *** restarting ICIs therapy,it is often recommended to use different types of *** grade 4 irAEs,permanent discontinuation of the medication is necessary.

关键词： Programmed cell death receptor-1 Programmed cell death-ligand 1 Cytotoxic T lymphocyte-associated antigen 4 Immune-related adverse events Immune-related gastritis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Low Cost, Green Sustainable and Biodegradable Biomass-based Fluorine-free Water and Oil Repellent

引用

Chinese Journal of Polymer Science 2024年第4期42卷 480-491页

作者： Zhi-Wei Shen shu-Feng Hu Chen Zeng Wei-Qing Kong Mei-fang Zhu State Key Laboratory for Modification of Chemical Fibers&Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510630China

With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.

关键词： Biomass Fluoride-free Oil-andwater-resistant Plasticfree

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Relationship between clinical belonging,professional identity,and nursing information ability among nursing interns:Model construction

引用

World Journal of Clinical Cases 2024年第13期12卷 2210-2217页

作者： Gai Zhang Shao-Juan Huang shu-fang Li Department of Nursing Foshan Hospital of Traditional Chinese MedicineFoshan 528000Guangdong ProvinceChina

BACKGROUND Clinical belonging refers to the feeling that clinical medical staff feel recognized and accepted by others or *** level of clinical belonging of nursing interns affects students’learning motivation and confidence,which in turn affects their clinical practice *** To explore the effects of professional identity and nursing information ability on clinical belonging among nursing interns and establish a relationship model for these *** The researchers used the convenience sampling method to select 682 nursing interns from *** survey was conducted using a general information questionnaire,clinical sense of belonging scale,nursing information ability self-assessment scale,and a nursing student professional identity *** mediating effect of nursing information ability between their professional identity and clinical sense of belonging was analyzed using SPSS 21.0 and the path analysis in structural equation *** The total scores of clinical belonging,professional identity,and nursing information ability of nursing interns were(104.29±13.11)points,(57.89±7.16)points,and(70.29±6.20)points,*** information ability had a direct effect on the clinical sense of belonging(effect value=0.46,P<0.05).Occupational identity had a direct effect(effect value=0.52,P<0.05)and an indirect effect(effect value=0.21,P<0.05)on clinical *** Nursing administrators in nursing colleges and hospitals should take effective measures to improve the professional identity and nursing information ability of nursing interns,as well as the clinical sense of belonging among nursing interns.

关键词： Belongingness Nursing Education Undergraduate Information literacy Models

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Strategies to advance thermoelectric performance of PbSe and PbS materials

引用

Rare Metals 2024年第9期43卷 4099-4114页

作者： Zheng-Hao Hou Xin Qian Qiu-Juan Cui shu-fang Wang Li-Dong Zhao Shijiazhuang Key Laboratory of Low Carbon Energy Materials College of Chemical EngineeringShijiazhuang UniversityShijiazhuang 050035China Hebei Key Lab of Optic-Electronic Information and Materials College of Physics Science and TechnologyHebei UniversityBaoding 071002China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Thermoelectric materials possess the unique capability to convert thermal energy into electric energy and vice versa,making them promising for waste heat recovery and efficient cooling ***,extensively investigated thermoelectric materials such as Bi2Te3,PbTe and GeTe exhibit superior thermoelectric properties at room temperature and medium temperature ***,the broad application of these thermoelectric materials has been impeded by the high cost and restricted accessibility of Te and Ge in the earth's *** the past few years,researchers have shown increasing interest in PbSe-and PbS-based materials,primarily attributed to their abundant elemental supply and relatively low *** assessment of research progress and a comprehensive overview of optimization strategies in time can significantly contribute to further improving the thermoelectric *** strategies include optimizing carrier concentration(aliovalent doping,dynamic doping and defect state),enhancing density-of-state effective mass(band convergence,band flattening and energy filtering effect),optimizing carrier mobility(band sharpening and band alignment)and reducing lattice thermal conductivity(all-scale hierarchical defect structures designing).This systematic summary and analysis provide novel insights and perspectives for the development of thermoelectric materials.

关键词： PbSe and PbS thermoelectric materials Carrier concentration Density-of-state effective mass Carrier mobility Lattice thermal conductivity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Research on Hepatocyte Regulation of PCSK9-LDLR and Its Related Drug Targets

引用

Chinese Journal of Integrative Medicine 2024年第7期30卷 664-672页

作者： LIU Su-su YU Tong QIAO Yan-fang GU shu-xiao CHAI Xin-lou School of Traditional Chinese Medicine Beijing University of Traditional Chinese MedicineBeijing102401China

The prevalence of hyperlipidemia has increased significantly due to genetic, dietary, nutritional and pharmacological factors, and has become one of the most common pathological conditions in humans. Hyperlipidemia can lead to a range of diseases such as atherosclerosis, stroke, coronary heart disease, myocardial infarction, diabetes, and kidney failure, etc. High circulating low-density lipoprotein cholesterol (LDL-C) is one of the causes of hyperlipidemia. LDL-C in the blood binds to LDL receptor (LDLR) and regulates cholesterol homeostasis through endocytosis. In contrast, proprotein convertase subtilisin/kexin type 9 (PCSK9) mediates LDLR degradation via the intracellular and extracellular pathways, leading to hyperlipidemia. Targeting PCSK9-synthesizing transcription factors and downstream molecules are important for development of new lipid-lowering drugs. Clinical trials regarding PCSK9 inhibitors have demonstrated a reduction in atherosclerotic cardiovascular disease events. The purpose of this review was to explore the target and mechanism of intracellular and extracellular pathways in degradation of LDLR and related drugs by PCSK9 in order to open up a new pathway for the development of new lipid-lowering drugs.

关键词： hyperlipidemia proprotein convertase subtilisin/kexin type 9 low-density lipoprotein receptor intracellular pathway extracellular pathway

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Copper oxide-modified highly reversible Zn powder anode for aqueous Zn metal batteries

引用

Rare Metals 2024年第10期43卷 5005-5016页

作者： Guan-Qun Liu Biao Fu Zhe-Xuan Liu Lan-Yan Li shu-Quan Liang Guo-Zhao fang School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan ProvinceCentral South University School of Science Hunan University of Technology and Business National Energy Metal Resources and New Materials Key Laboratory Central South University

With the advantages of mature preparation technology,structural adjustability and suitability for large-scale application,Zn powder anode is considered to be an ideal electrode for realizing low-cost,high-energy-density aqueous Zn metal ***,the high specific surface of Zn powders leads to severe side reactions such as hydrogen evolution and corrosion,thus limiting their widespread use Here,this work develops a novel CuO@Zn powder anode with a synergy effect of surface wrapping and *** powders are uniformly wrapped by small CuO particles due to the strong adsorption between Zn and *** wrapped CuO particles build a good conductive framework to inhibit the structural collapse of the Zn powder caused by corrosion and non-uniform ***,CuO can also be used as a seed to guide the uniform deposition of Zn ions through its strong binding energy with *** a result,the Cu O@Zn anode can maintain a long cyclic life of 900 h at current density of 1 mA·cm-2and capacity of 1 mAh·cm-2,as well as contribute to an excellent capacity retention of 92%after 800cycles for CuO@Zn||NH4V4O10full *** at high current density of 5 A·g-1,the full cell exhibits a specific capacity of more than 200 mAh·g-1after 800 cycles,with a good capacity retention of 89%.This work provides a new idea for developing high-performance Zn powder-based anodes.

关键词： Aqueous Zn metal batteries Copper oxide Surface wrapping Zn anode Zn powder

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Advance in reversible Zn anodes promoted by 2D materials

引用

Rare Metals 2024年第4期43卷 1350-1369页

作者： shu-Yuan Lei Jin-Xiu Feng Yu-Chao Chen Dong Zheng Wen-Xian Liu Wen-Hui Shi fang-fang Wu Xie-Hong Cao School of Materials Science and Engineering Zhejiang University of TechnologyHangzhou310014China Center for Membrane Separation and Water Science and Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

With the growing energy demand associated with high safety and low-cost requirement,aqueous zinc-ion batteries(AZIBs)have been considered as one of the most promising next-generation ***,some key issues,such as uncontrollable dendrites growth,severe corrosion,hydrogen evolution and side reactions of Zn anodes during charge/discharge process,have hindered its pragmatic ***-dimensional(2D)materials hold advantages of unique physical and chemical properties,large surface areas and abundant active sites,which have been successfully used to overcome the above shortcomings of Zn anodes in recent *** this review,the issues and challenges of Zn anodes are ***,the state-of-the-art progress on Zn anodes modification based on 2D materials such as graphene,2D metal carbides and nitrides(MXenes),2D metal-organic frameworks(MOFs),2D covalent organic frameworks(COFs),2D transition metal compounds and other 2D materials is discussed in ***,the perspectives of employing 2D materials in highly reversible Zn anodes are summarized and discussed.

关键词： 2D materials Aqueous zinc-ion battery Zn anodes Dendrites growth

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：