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Geological suitability of natural sponge body for the construction of sponge city——a case study of Shuanghe Lake district in Zhengzhou airport zone 被引量:1
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作者 Yong-jun Su Hui Tang +4 位作者 Ai-min Wu Xue-ping Dai shuang liu Hong-wei liu Heng Kuang 《Journal of Groundwater Science and Engineering》 2023年第2期146-157,共12页
Natural and geological environmental conditions have an important impact on the planning and construction of sponge cities.This paper analyzes geological factors that influence the usage of natural sponge bodies,takin... Natural and geological environmental conditions have an important impact on the planning and construction of sponge cities.This paper analyzes geological factors that influence the usage of natural sponge bodies,taking the Shuanghe lake district of Zhengzhou airport zone as an example.An evaluation system with seven factors has been established and the weights of these factors are determined using the analytic hierarchy process(AHP)method.Overlay analysis is then carried out on all factors using GIS to evaluate the geological suitability of the construction of the sponge city.The results show that geologically suitable area for city construction in Shuanghe lake district accounts for 12.3%,relatively suitable area accounts for 76.1%,and relatively unsuitable area accounts for 11.6%.For suitable and relatively suitable areas,we should make full use of the advantages of surface infiltration,vadose zone transportation and aquifer storage to build a sponge city infrastructure with geological engineering as the main component,supplemented by engineering measures such as surface water storage and drainage,and jointly establish a sustainable urban hydrological cycle.For less suitable areas,artificial rain and flood control works,such as roof garden,should be considered.The findings of this paper can serve as an important reference for sponge city planning and construction not only in the research area but also in other regions with similar geological conditions. 展开更多
关键词 Natural sponge bodies Low impact development Rain flood control Hierarchy analysis
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Self‑Assembly of Binderless MXene Aerogel for Multiple‑Scenario and Responsive Phase Change Composites with Ultrahigh Thermal Energy Storage Density and Exceptional Electromagnetic Interference Shielding
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作者 Chuanbiao Zhu Yurong Hao +8 位作者 Hao Wu Mengni Chen Bingqing Quan shuang liu Xinpeng Hu Shilong liu Qinghong Ji Xiang Lu Jinping Qu 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期367-382,共16页
The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here... The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here,we introduced metal ions to induce the self-assembly of MXene nanosheets and achieve their ordered arrangement by combining suction filtration and rapid freezing.Subsequently,a series of MXene/K^(+)/paraffin wax(PW)phase change composites(PCCs)were obtained via vacuum impregnation in molten PW.The prepared MXene-based PCCs showed versatile applications from macroscale technologies,successfully transforming solar,electric,and magnetic energy into thermal energy stored as latent heat in the PCCs.Moreover,due to the absence of binder in the MXene-based aerogel,MK3@PW exhibits a prime solar-thermal conversion efficiency(98.4%).Notably,MK3@PW can further convert the collected heat energy into electric energy through thermoelectric equipment and realize favorable solar-thermal-electric conversion(producing 206 mV of voltage with light radiation intensity of 200 mw cm^(−2)).An excellent Joule heat performance(reaching 105℃with an input voltage of 2.5 V)and responsive magnetic-thermal conversion behavior(a charging time of 11.8 s can achieve a thermal insulation effect of 285 s)for contactless thermotherapy were also demonstrated by the MK3@PW.Specifically,as a result of the ordered arrangement of MXene nanosheet self-assembly induced by potassium ions,MK3@PW PCC exhibits a higher electromagnetic shielding efficiency value(57.7 dB)than pure MXene aerogel/PW PCC(29.8 dB)with the same MXene mass.This work presents an opportunity for the multi-scene response and practical application of PCMs that satisfy demand of next-generation multifunctional PCCs. 展开更多
关键词 Self-assembly Multiple-scenario Phase change composites Thermal energy storage Electromagnetic interference shielding
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Long-term prognosis and its associated predictive factors in patients with eosinophilic gastroenteritis
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作者 Kai-Wen Li Ge-Chong Ruan +8 位作者 shuang liu Tian-Ming Xu Ye Ma Wei-Xun Zhou Wei liu Peng-Yu Zhao Zhi-Rong Du Ji Li Jing-Nan Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第2期146-157,共12页
BACKGROUND Eosinophilic gastroenteritis(EGE)is a chronic recurrent disease with abnormal eosinophilic infiltration in the gastrointestinal tract.Glucocorticoids remain the most common treatment method.However,disease ... BACKGROUND Eosinophilic gastroenteritis(EGE)is a chronic recurrent disease with abnormal eosinophilic infiltration in the gastrointestinal tract.Glucocorticoids remain the most common treatment method.However,disease relapse and glucocorticoid dependence remain notable problems.To date,few studies have illuminated the prognosis of EGE and risk factors for disease relapse.AIM To describe the clinical characteristics of EGE and possible predictive factors for disease relapse based on long-term follow-up.METHODS This was a retrospective cohort study of 55 patients diagnosed with EGE admitted to one medical center between 2013 and 2022.Clinical records were collected and analyzed.Kaplan-Meier curves and log-rank tests were conducted to reveal the risk factors for long-term relapse-free survival(RFS).RESULTS EGE showed a median onset age of 38 years and a slight female predominance(56.4%).The main clinical symptoms were abdominal pain(89.1%),diarrhea(61.8%),nausea(52.7%),distension(49.1%)and vomiting(47.3%).Forty-three(78.2%)patients received glucocorticoid treatment,and compared with patients without glucocorticoid treatments,they were more likely to have elevated serum immunoglobin E(IgE)(86.8%vs 50.0%,P=0.022)and descending duodenal involvement(62.8%vs 27.3%,P=0.046)at diagnosis.With a median follow-up of 67 mo,all patients survived,and 56.4%had at least one relapse.Six variables at baseline might have been associated with the overall RFS rate,including age at diagnosis<40 years[hazard ratio(HR)2.0408,95%confidence interval(CI):1.0082–4.1312,P=0.044],body mass index(BMI)>24 kg/m^(2)(HR 0.3922,95%CI:0.1916-0.8027,P=0.014),disease duration from symptom onset to diagnosis>3.5 mo(HR 2.4725,95%CI:1.220-5.0110,P=0.011),vomiting(HR 3.1259,95%CI:1.5246-6.4093,P=0.001),total serum IgE>300 KU/L at diagnosis(HR 0.2773,95%CI:0.1204-0.6384,P=0.022)and glucocorticoid treatment(HR 6.1434,95%CI:2.8446-13.2676,P=0.003).CONCLUSION In patients with EGE,younger onset age,longer disease course,vomiting and glucocorticoid treatment were risk factors for disease relapse,whereas higher BMI and total IgE level at baseline were protective. 展开更多
关键词 Eosinophilic gastroenteritis PROGNOSIS RELAPSE GLUCOCORTICOID Glucocorticoid dependence
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Using MsfNet to Predict the ISUP Grade of Renal Clear Cell Carcinoma in Digital Pathology Images
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作者 Kun Yang Shilong Chang +5 位作者 Yucheng Wang Minghui Wang Jiahui Yang shuang liu Kun liu Linyan Xue 《Computers, Materials & Continua》 SCIE EI 2024年第1期393-410,共18页
Clear cell renal cell carcinoma(ccRCC)represents the most frequent form of renal cell carcinoma(RCC),and accurate International Society of Urological Pathology(ISUP)grading is crucial for prognosis and treatment selec... Clear cell renal cell carcinoma(ccRCC)represents the most frequent form of renal cell carcinoma(RCC),and accurate International Society of Urological Pathology(ISUP)grading is crucial for prognosis and treatment selection.This study presents a new deep network called Multi-scale Fusion Network(MsfNet),which aims to enhance the automatic ISUP grade of ccRCC with digital histopathology pathology images.The MsfNet overcomes the limitations of traditional ResNet50 by multi-scale information fusion and dynamic allocation of channel quantity.The model was trained and tested using 90 Hematoxylin and Eosin(H&E)stained whole slide images(WSIs),which were all cropped into 320×320-pixel patches at 40×magnification.MsfNet achieved a micro-averaged area under the curve(AUC)of 0.9807,a macro-averaged AUC of 0.9778 on the test dataset.The Gradient-weighted Class Activation Mapping(Grad-CAM)visually demonstrated MsfNet’s ability to distinguish and highlight abnormal areas more effectively than ResNet50.The t-Distributed Stochastic Neighbor Embedding(t-SNE)plot indicates our model can efficiently extract critical features from images,reducing the impact of noise and redundant information.The results suggest that MsfNet offers an accurate ISUP grade of ccRCC in digital images,emphasizing the potential of AI-assisted histopathological systems in clinical practice. 展开更多
关键词 Renal cell carcinoma computer-aided diagnosis pathology image deep learning machine learning
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Identification of different degrees of processed ginger using GC-IMS combined with machine learning
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作者 shuang liu Hongjing Dong +2 位作者 Minmin Zhang Wei Geng Xiao Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第1期149-151,共3页
Ginger,the rhizomes of Zingiber officinale Roscoe,was a wellknown edible plant species commonly used in China,which has pungent flavor[1].Ginger has numerous chemical compounds,such as phenolic constituents,volatile c... Ginger,the rhizomes of Zingiber officinale Roscoe,was a wellknown edible plant species commonly used in China,which has pungent flavor[1].Ginger has numerous chemical compounds,such as phenolic constituents,volatile compounds(VOCs),and polysaccharides[2].Among them,VOCs are considered one of the effective compounds in ginger due to their functional properties,including anti-inflammatory,antioxidant,and analgesic[3]. 展开更多
关键词 PHENOLIC EDIBLE RHIZOME
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Interception of Layered LP-N and HLP-N at Ambient Conditions by Confined Template
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作者 王冬雪 付静 +3 位作者 李义 姚震 刘爽 刘冰冰 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期61-72,共12页
We propose a feasible strategy of intercepting the layered polymeric nitrogen(LP-N)and hexagonal layered polymeric nitrogen(HLP-N)at ambient conditions by using the confinement templates.The stable mechanism of confin... We propose a feasible strategy of intercepting the layered polymeric nitrogen(LP-N)and hexagonal layered polymeric nitrogen(HLP-N)at ambient conditions by using the confinement templates.The stable mechanism of confined LP-N and HLP-N at ambient conditions is revealed. 展开更多
关键词 AMBIENT LAYERED polymeric
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Finite Element Method Simulation of Wellbore Stability under Different Operating and Geomechanical Conditions
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作者 Junyan liu Ju liu +3 位作者 Yan Wang shuang liu Qiao Wang Yihe Du 《Fluid Dynamics & Materials Processing》 EI 2024年第1期205-218,共14页
The variation of the principal stress of formations with the working and geo-mechanical conditions can trigger wellbore instabilities and adversely affect the well completion.A finite element model,based on the theory... The variation of the principal stress of formations with the working and geo-mechanical conditions can trigger wellbore instabilities and adversely affect the well completion.A finite element model,based on the theory of poro-elasticity and the Mohr-Coulomb rock damage criterion,is used here to analyze such a risk.The changes in wellbore stability before and after reservoir acidification are simulated for different pressure differences.The results indicate that the risk of wellbore instability grows with an increase in the production-pressure difference regardless of whether acidification is completed or not;the same is true for the instability area.After acidizing,the changes in the main geomechanical parameters(i.e.,elastic modulus,Poisson’s ratio,and rock strength)cause the maximum wellbore instability coefficient to increase. 展开更多
关键词 Wellbore stability finite element acidizing operation well completion
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Protein succinylation,hepatic metabolism,and liver diseases
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作者 shuang liu Rui Li +2 位作者 Ya-Wen Sun Hai Lin Hai-Fang Li 《World Journal of Hepatology》 2024年第3期344-352,共9页
Succinylation is a highly conserved post-translational modication that is processed via enzymatic and non-enzymatic mechanisms.Succinylation exhibits strong effects on protein stability,enzyme activity,and transcripti... Succinylation is a highly conserved post-translational modication that is processed via enzymatic and non-enzymatic mechanisms.Succinylation exhibits strong effects on protein stability,enzyme activity,and transcriptional regulation.Protein succinylation is extensively present in the liver,and increasing evidence has demonstrated that succinylation is closely related to hepatic metabolism.For instance,histone acetyltransferase 1 promotes liver glycolysis,and the sirtuin 5-induced desuccinylation is involved in the regulation of the hepatic urea cycle and lipid metabolism.Therefore,the effects of succinylation on hepatic glucose,amino acid,and lipid metabolism under the action of various enzymes will be discussed in this work.In addition,how succinylases regulate the progression of different liver diseases will be reviewed,including the desuccinylation activity of sirtuin 7,which is closely associated with fatty liver disease and hepatitis,and the actions of lysine acetyltransferase 2A and histone acetyltransferase 1 that act as succinyltransferases to regulate the succinylation of target genes that influence the development of hepatocellular carcinoma.In view of the diversity and significance of protein succinylation,targeting the succinylation pathway may serve as an attractive direction for the treatment of liver diseases. 展开更多
关键词 Protein succinylation Hepatic metabolism Fatty liver HEPATITIS Hepatocellular carcinoma
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Discussion on the Ideological and Political Education for Poor College Students
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作者 Jie Li Yang liu +1 位作者 shuang liu Cen Yan 《Journal of Contemporary Educational Research》 2024年第1期133-139,共7页
At present,ideological and political education is significant for poor college students.The focus of funding for poor students has gradually transformed from providing economic support for them to ideological and spir... At present,ideological and political education is significant for poor college students.The focus of funding for poor students has gradually transformed from providing economic support for them to ideological and spiritual help,which puts forward higher requirements on how to carry out ideological and political work.It also requires us to advance the work of ideological and moral education and put it in the most important position in the ideological and educational work for poor college students.Combined with the reality of poor college students,we will adhere to the idea of being student-oriented and endeavor to enhance the effectiveness,pertinence,and relevance of the work of ideological and political education.This paper analyzes the significance and problems of ideological and political education for poor college students and puts forward effective ways to solve the problems from the levels of ideology,cognition,and teaching staff. 展开更多
关键词 Ideological and political education Poor college students Mechanism improvement
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BODIPY荧光探针的合成及次氯酸检测的综合实验
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作者 刘振波 肖佳月 +4 位作者 刘爽 姜文硕 兰欣宇 贾文萱 李天愉 《大学化学》 CAS 2023年第5期193-201,共9页
有机实验和仪器分析实验是本科生阶段化学教学的重点内容,虽然现有的教学实验内容已十分丰富与完善,但缺少两者之间的融合以及与科研领域的联系。针对上述不足,我们将科学研究前沿和热点的荧光检测技术引入教学实践。实验通过对BODIPY ... 有机实验和仪器分析实验是本科生阶段化学教学的重点内容,虽然现有的教学实验内容已十分丰富与完善,但缺少两者之间的融合以及与科研领域的联系。针对上述不足,我们将科学研究前沿和热点的荧光检测技术引入教学实践。实验通过对BODIPY (氟硼二吡咯)荧光染料结构的设计改良,合成一种具有快速响应、选择性高和灵敏度好的新型次氯酸荧光探针,对荧光探针结构进行表征,并测定荧光探针的荧光性质。通过对探针结构与荧光性质之间关系的研究,有助于加深学生荧光发光原理的理解。实验内容涵盖有机合成、产物仪器表征、光谱分析等方面,综合性强且易于学生操作。教学实践过程有助于培养学生的科学思维、理论与实践相结合的能力。 展开更多
关键词 荧光探针 有机实验 仪器分析实验 综合性
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1例碘美普尔肾损伤致依诺肝素严重肝损伤病例的药学实践 被引量:1
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作者 杨强 刘双 +1 位作者 米佳丽 张鹏 《药物流行病学杂志》 CAS 2023年第7期836-840,共5页
1例67岁的男性肺腺癌合并心力衰竭患者在使用碘美普尔后出现急性肾损伤(血清肌酐149μmol·L^(-1),尿素氮13.23 mmol·L^(-1),尿酸439μmol·L^(-1))和严重肝损伤(丙氨酸氨基转移酶592 U·L^(-1),天冬氨酸氨基转移酶782... 1例67岁的男性肺腺癌合并心力衰竭患者在使用碘美普尔后出现急性肾损伤(血清肌酐149μmol·L^(-1),尿素氮13.23 mmol·L^(-1),尿酸439μmol·L^(-1))和严重肝损伤(丙氨酸氨基转移酶592 U·L^(-1),天冬氨酸氨基转移酶782 U·L^(-1),γ-谷氨酰转移酶121 U·L^(-1))。通过用药分析,药师判断该患者使用碘美普尔对比剂后引发急性肾损伤,导致依诺肝素钠在体内蓄积,继发严重肝损伤。药师建议观察肾功能变化并停用依诺肝素钠、暂停甲磺酸阿美替尼,此后患者肝肾功能均恢复正常。该病例提示对于具有对比剂肾病高危因素的患者,使用对比剂后可能出现急性肾损伤,引起药物蓄积性不良反应。对这类患者药师应做好药学监护,发生不良反应后及时进行用药分析和充分的临床评估,协助医生调整治疗方案。 展开更多
关键词 碘美普尔 肾损伤 依诺肝素 肝损伤 药学监护
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High expression of PD-L1 mainly occurs in non-small cell lung cancer patients with squamous cell carcinoma or poor differentiation 被引量:2
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作者 LU liu BIN XIE +5 位作者 WEI ZHU QIUYAN HE JIANHUA ZHOU shuang liu YONGGUANG TAO DESHENG XIAO 《Oncology Research》 SCIE 2023年第3期275-286,共12页
Background:Lung cancer is one of the most lethal cancers worldwide,but studies have shown that the higher the expression of programmed cell death protein 1 ligand 1(PD-L1)in non-small cell lung cancer(NSCLC),the more ... Background:Lung cancer is one of the most lethal cancers worldwide,but studies have shown that the higher the expression of programmed cell death protein 1 ligand 1(PD-L1)in non-small cell lung cancer(NSCLC),the more likely it will benefit from anti-PD-L1 immunotherapy.The purpose of our study was to collect and analyze abundant clinical samples in order to provide evidence for clinicians and patients who might consider anti-PD-L1 immunotherapy while jointly formulating treatment plans.Methods:On the one hand,we obtained cases from The Cancer Genome Atlas(TCGA)database,including 498 lung squamous cell cancer(LUSC)patients and 515 lung adenocarcinoma(LUAD)patients.We studied the lung caner driver gene in LUSC and LUAD.On the other hand,PD-L1 expression was detected in lung cancer tissues of 1,008 NSCLC patients with immunohistochemistry staining(IHC),and we studied the correlation between PD-L1 protein expression and clinicopathological characteristics.Results:PD-L1 expression was higher in LUSC than in LUAD at the mRNA level.In univariate analysis,PD-L1 expression at the protein level was higher in patients who were males,were LUSC,were smokers,had a tumor diameter>3 cm,had poor differentiation,or had stages Ⅲ-Ⅳ disease.In multivariate analysis,PD-L1 expression was higher in patients who were LUSC or in poor differentiation.Conclusion:In term of protein level,PD-L1 expression was higher in NSCLC patients who were LUSC or in poor differentiation.We recommend that PD-L1 IHC detection can be routinely performed in such populations that are likely to benefit most from PD-L1 immunotherapy. 展开更多
关键词 NSCLC PD-L1 IMMUNOTHERAPY LUSC LUAD
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Residual Feature Attentional Fusion Network for Lightweight Chest CT Image Super-Resolution 被引量:1
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作者 Kun Yang Lei Zhao +4 位作者 Xianghui Wang Mingyang Zhang Linyan Xue shuang liu Kun liu 《Computers, Materials & Continua》 SCIE EI 2023年第6期5159-5176,共18页
The diagnosis of COVID-19 requires chest computed tomography(CT).High-resolution CT images can provide more diagnostic information to help doctors better diagnose the disease,so it is of clinical importance to study s... The diagnosis of COVID-19 requires chest computed tomography(CT).High-resolution CT images can provide more diagnostic information to help doctors better diagnose the disease,so it is of clinical importance to study super-resolution(SR)algorithms applied to CT images to improve the reso-lution of CT images.However,most of the existing SR algorithms are studied based on natural images,which are not suitable for medical images;and most of these algorithms improve the reconstruction quality by increasing the network depth,which is not suitable for machines with limited resources.To alleviate these issues,we propose a residual feature attentional fusion network for lightweight chest CT image super-resolution(RFAFN).Specifically,we design a contextual feature extraction block(CFEB)that can extract CT image features more efficiently and accurately than ordinary residual blocks.In addition,we propose a feature-weighted cascading strategy(FWCS)based on attentional feature fusion blocks(AFFB)to utilize the high-frequency detail information extracted by CFEB as much as possible via selectively fusing adjacent level feature information.Finally,we suggest a global hierarchical feature fusion strategy(GHFFS),which can utilize the hierarchical features more effectively than dense concatenation by progressively aggregating the feature information at various levels.Numerous experiments show that our method performs better than most of the state-of-the-art(SOTA)methods on the COVID-19 chest CT dataset.In detail,the peak signal-to-noise ratio(PSNR)is 0.11 dB and 0.47 dB higher on CTtest1 and CTtest2 at×3 SR compared to the suboptimal method,but the number of parameters and multi-adds are reduced by 22K and 0.43G,respectively.Our method can better recover chest CT image quality with fewer computational resources and effectively assist in COVID-19. 展开更多
关键词 SUPER-RESOLUTION COVID-19 chest CT lightweight network contextual feature extraction attentional feature fusion
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Multi-Classification of Polyps in Colonoscopy Images Based on an Improved Deep Convolutional Neural Network 被引量:1
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作者 shuang liu Xiao liu +9 位作者 Shilong Chang Yufeng Sun Kaiyuan Li Ya Hou Shiwei Wang Jie Meng Qingliang Zhao Sibei Wu Kun Yang Linyan Xue 《Computers, Materials & Continua》 SCIE EI 2023年第6期5837-5852,共16页
Achieving accurate classification of colorectal polyps during colonoscopy can avoid unnecessary endoscopic biopsy or resection.This study aimed to develop a deep learning model that can automatically classify colorect... Achieving accurate classification of colorectal polyps during colonoscopy can avoid unnecessary endoscopic biopsy or resection.This study aimed to develop a deep learning model that can automatically classify colorectal polyps histologically on white-light and narrow-band imaging(NBI)colonoscopy images based on World Health Organization(WHO)and Workgroup serrAted polypS and Polyposis(WASP)classification criteria for colorectal polyps.White-light and NBI colonoscopy images of colorectal polyps exhibiting pathological results were firstly collected and classified into four categories:conventional adenoma,hyperplastic polyp,sessile serrated adenoma/polyp(SSAP)and normal,among which conventional adenoma could be further divided into three sub-categories of tubular adenoma,villous adenoma and villioustublar adenoma,subsequently the images were re-classified into six categories.In this paper,we proposed a novel convolutional neural network termed Polyp-DedNet for the four-and six-category classification tasks of colorectal polyps.Based on the existing classification network ResNet50,Polyp-DedNet adopted dilated convolution to retain more high-dimensional spatial information and an Efficient Channel Attention(ECA)module to improve the classification performance further.To eliminate gridding artifacts caused by dilated convolutions,traditional convolutional layers were used instead of the max pooling layer,and two convolutional layers with progressively decreasing dilation were added at the end of the network.Due to the inevitable imbalance of medical image data,a regularization method DropBlock and a Class-Balanced(CB)Loss were performed to prevent network overfitting.Furthermore,the 5-fold cross-validation was adopted to estimate the performance of Polyp-DedNet for the multi-classification task of colorectal polyps.Mean accuracies of the proposed Polyp-DedNet for the four-and six-category classifications of colorectal polyps were 89.91%±0.92%and 85.13%±1.10%,respectively.The metrics of precision,recall and F1-score were also improved by 1%∼2%compared to the baseline ResNet50.The proposed Polyp-DedNet presented state-of-the-art performance for colorectal polyp classifying on white-light and NBI colonoscopy images,highlighting its considerable potential as an AI-assistant system for accurate colorectal polyp diagnosis in colonoscopy. 展开更多
关键词 Colorectal polyps four-and six-category classifications convolutional neural network dilated residual network
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Joint computation offloading and resource allocation in vehicular edge computing networks
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作者 shuang liu Jie Tian +1 位作者 Chao Zhai Tiantian Li 《Digital Communications and Networks》 SCIE CSCD 2023年第6期1399-1410,共12页
Vehicular Edge Computing(VEC)is a promising technique to accommodate the computation-intensive and delaysensitive tasks through offloading the tasks to the RoadSide-Unit(RSU)equipped with edge computing servers or nei... Vehicular Edge Computing(VEC)is a promising technique to accommodate the computation-intensive and delaysensitive tasks through offloading the tasks to the RoadSide-Unit(RSU)equipped with edge computing servers or neighboring vehicles.Nevertheless,the limited computation resources of edge computing servers and the mobility of vehicles make the offloading policy design very challenging.In this context,through considering the potential transmission gains brought by the mobility of vehicles,we propose an efficient computation offloading and resource allocation scheme in VEC networks with two kinds of offloading modes,i.e.,Vehicle to Vehicle(V2V)and Vehicle to RSU(V2R).We define a new cost function for vehicular users by incorporating the vehicles’offloading delay,energy consumption,and expenses with a differentiated pricing strategy,as well as the transmission gain.An optimization problem is formulated to minimize the average cost of all the task vehicles under the latency and computation capacity constraints.A distributed iterative algorithm is proposed by decoupling the problem into two subproblems for the offloading mode selection and the resource allocation.Matching theorybased and Lagrangian-based algorithms are proposed to solve the two subproblems,respectively.Simulation results show the proposed algorithm achieves low complexity and significantly improves the system performance compared with three benchmark schemes. 展开更多
关键词 Vehicular edge computing Task offloading Matching theory Lagrangian method Distributed algorithm
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Pressure-induced structural transition and low-temperature recovery of sodium pentazolate
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作者 赵梓彤 刘然 +6 位作者 郭琳琳 刘爽 隋明宏 刘波 姚震 王鹏 刘冰冰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期529-533,共5页
Pentazolate compounds have attracted extensive attention as high energy density materials.The synthesis and recovery of pentazolate compounds is of great importance for their potential applications.Here,we report the ... Pentazolate compounds have attracted extensive attention as high energy density materials.The synthesis and recovery of pentazolate compounds is of great importance for their potential applications.Here,we report the synthesis of Pmn2_(1)-NaN_(5)and Pm-Na_(2)N_(5)through compressing and laser heating pure NaN_(3)at~60 GPa.Upon decompression,the pressureinduced structural transition from Pmn2_(1)-NaN_(5)into Cm-NaN_(5)is observed in the pressure range of 14-23 GPa for the first time.The cyclo-N_(5)^(-)can be traced down to 4.7 GPa at room temperature and recovered to ambient pressure under low temperature condition(up to 160 K).The Pm-Na_(2)N_(5)is suggested to decompose into the P4/mmm-NaN_(2)at 23 GPa,and be stable at ambient conditions.This work provides insight into the high-pressure behaviors of pentazolate compounds and an alternative way to stabilize energetic polynitrogen compounds. 展开更多
关键词 sodium pentazolate high pressure laser heating structural transition
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Study of the geomagnetic field's regional gradients in Chinese continent using three-dimensional surface Spline model
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作者 Yan Feng YiJun Li +3 位作者 JinYan Zhang shuang liu Abbas Nasir Ya Huang 《Earth and Planetary Physics》 EI CSCD 2023年第1期74-83,共10页
We combined domestic ground-based and satellite magnetic measurements to create a regional three-dimensional surface Spline(3DSS)gradient model of the main geomagnetic field over the Chinese continent.To improve the p... We combined domestic ground-based and satellite magnetic measurements to create a regional three-dimensional surface Spline(3DSS)gradient model of the main geomagnetic field over the Chinese continent.To improve the precision of the model,we considered the data gap between the ground and satellite data.We compared and analyzed the results of the Taylor polynomial,surface Spline,and CHAOS-6(the CHAMP,?rsted and SAC-C model of Earth’s magnetic field)gradient models.Results showed that the gradients in the south-north and east-west directions of the four models were consistent.The 3DSS model was able to express not only gradients at different altitudes,but also average gradients inside the research area.The two Spline models were able to capture more information on gradient anomalies than were the fitted models.Strong local anomalies were observed in northern Xinjiang,Beijing,and the junction area between Jiangsu and Zhejiang,and the total intensity F decreased whereas the altitude increased.The gradient decreased by 21.69%in the south-north direction and increased by 11.78%in the east-west direction.In addition,the altitude gradient turned from negative to positive while the altitude increased.The Spline model and the two fitted models differed mainly in the field sources they expressed and the modeling theory. 展开更多
关键词 geomagnetic field main field gradients regional model three-dimensional modeling
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飞秒激光术中角膜基质不透明气泡层的研究进展
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作者 刘爽 秦兵 +1 位作者 王珞羽 孙红艳 《国际眼科杂志》 CAS 北大核心 2023年第11期1859-1864,共6页
飞秒激光辅助的准分子激光原位角膜磨镶术(FS-LASIK)和飞秒激光小切口角膜基质透镜取出术(SMILE)是目前主流的角膜屈光手术方式。虽然临床研究显示其具有很高的安全性、有效性和可预测性,但制作角膜瓣或透镜时需要依赖飞秒激光,不可避... 飞秒激光辅助的准分子激光原位角膜磨镶术(FS-LASIK)和飞秒激光小切口角膜基质透镜取出术(SMILE)是目前主流的角膜屈光手术方式。虽然临床研究显示其具有很高的安全性、有效性和可预测性,但制作角膜瓣或透镜时需要依赖飞秒激光,不可避免地会发生飞秒激光相关并发症,如负压失吸、不透明气泡层(OBL)等。OBL是飞秒激光在角膜组织中发生光爆破作用时产生的二氧化碳和水蒸气聚集体在角膜基质中无法及时排出而形成,是飞秒激光手术特有的并发症。气泡可能会干扰术中操作和影响术后视觉质量。本文就OBL形成的机制、分级和分类、影响因素及其对术中操作和术后效果的影响进行综述,以期为进一步临床工作提供参考和依据。 展开更多
关键词 不透明气泡层(OBL) 飞秒激光 飞秒激光辅助的准分子激光原位角膜磨镶术(FS-LASIK) 飞秒激光小切口角膜基质透镜取出术(SMILE)
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化妆品中防腐剂的应用现状及检测技术研究进展
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作者 朱海荣 孙胜敏 +3 位作者 张娟 刘爽 刘倩倩 邹惠玲 《日用化学工业(中英文)》 CAS 北大核心 2023年第6期679-685,共7页
化妆品中的防腐剂在抑制微生物生长、延长产品保质期方面发挥了重要作用,但其使用不当会损害人体健康并对环境和生态安全造成潜在危害。随着化妆品安全事件的频发,居民消费安全意识的提升和行业监管法规趋严,防腐剂的添加状况成为社会... 化妆品中的防腐剂在抑制微生物生长、延长产品保质期方面发挥了重要作用,但其使用不当会损害人体健康并对环境和生态安全造成潜在危害。随着化妆品安全事件的频发,居民消费安全意识的提升和行业监管法规趋严,防腐剂的添加状况成为社会各界的关注焦点。文章总结了当前化妆品中防腐剂的使用现状,梳理了近年来常规检测技术在化妆品中防腐剂领域的最新应用,介绍了高效液相色谱-电感耦合等离子体质谱法和激光解吸附离子化质谱等新型检测手段。分析了化妆品中防腐剂的市场发展前景和检测技术发展方向,为今后化妆品中防腐剂的监管和高通量快速检测提供借鉴。 展开更多
关键词 化妆品 防腐剂 应用 检测技术
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The study of geomagnetic jerk from 2010 to 2021 based on hourly mean data from global geomagnetic observatories
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作者 YiJun Li Yan Feng +3 位作者 SuQin Zhang shuang liu JinYuan Zhang GuanChun Wei 《Earth and Planetary Physics》 EI CSCD 2023年第1期39-48,共10页
The secular variation in the global geomagnetic field was analyzed in terms of the annual differences in monthly means by using the hourly mean data from 18 foreign(outside China)observatories of the World Data Center... The secular variation in the global geomagnetic field was analyzed in terms of the annual differences in monthly means by using the hourly mean data from 18 foreign(outside China)observatories of the World Data Center(WDC)for Geomagnetism from January 2010 to January 2020 as well as 9 observatories in the Geomagnetic Network of China from January 2015 to April 2021.In addition,according to the correlation of noisy components from the observatories,a covariance matrix was constructed based on residuals between observations and the CHAOS-7.4 model to remove external contamination.Through a comparison before and after denoising,we found that the overall average standard deviations were reduced by 29.97%in China and by 41.4%outside China.Results showed the correlation coefficient between external noise(mainly the magnetosphere ring current)and the Dst index was 0.82,and the correlation coefficient between external noise and the Ring Current(RC)index reached 0.94.A geomagnetic jerk was globally discovered around 2018.0 on the geomagnetic eastward component Y.The jerk timing in China was around 2020.0,and the earliest one was in2018.75,whereas the timing outside China was around 2018.0,and the earliest one was in 2017.67.This 2-year lag may have been caused by the higher electrical conductivity of the deep mantle.After more data were added,this jerk event was found to occur in an orderly manner in the northern hemisphere as the longitude increased and the intensity gradually increased as well.The variations in location of the jerk center were analyzed according to the CHAOS-7.4 model.Results revealed six extreme points distributed nearby the equator.The strongest was near the equator,at 170°E,and the strength gradually decreased as it extended to the northern and southern hemispheres.Another extreme point with the opposite sign was located at the equator,at 20°W,in the south-central part of the Atlantic,and the strength gradually decreased as it extended into Europe.The covariance matrix method can be used to analyze data from the Macao Science Satellite-1 mission in the future,and this method is expected to play a positive role in modeling and separating the large-scale external field. 展开更多
关键词 geomagnetic field secular variation JERK covariance matrix
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