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一个基于Mix net的电子投票方案 被引量:8
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作者 高虎明 王继林 王育民 《电子学报》 EI CAS CSCD 北大核心 2004年第6期1047-1049,共3页
电子投票是电子政务活动中的一项基本功能 .本文设计了一个新的具有 (t- 1,N - 2 ) AA弹性的可验证Mixnet协议 ,该协议具有秘密性、正确性和可验证性 .协议所需的通信量和计算量优于已知方案 .利用它给出了一个电子投票方案 ,具有选举... 电子投票是电子政务活动中的一项基本功能 .本文设计了一个新的具有 (t- 1,N - 2 ) AA弹性的可验证Mixnet协议 ,该协议具有秘密性、正确性和可验证性 .协议所需的通信量和计算量优于已知方案 .利用它给出了一个电子投票方案 ,具有选举的秘密性、唯一性、完整性、匿名性、可公开性、可验证性等优点 ,适宜于大规模选举 . 展开更多
关键词 电子投票 mix net 选民的匿名性 公开可验证性
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一个新的(t,N-2)弹性的Mix Net 被引量:3
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作者 高虎明 陈晓峰 王育民 《计算机学报》 EI CSCD 北大核心 2003年第10期1361-1365,共5页
Mixnet是实现匿名通信、电子投票选举、电子支付以及电子投标的有力工具 .该文建立了 (t,N - 2 )Mixnet模型 ,利用Shamir门限方案、ElGamal公钥体制、零知识证明等密码技术设计了一个基于这个模型的Mixnet协议 .该协议将同一密文组让不... Mixnet是实现匿名通信、电子投票选举、电子支付以及电子投标的有力工具 .该文建立了 (t,N - 2 )Mixnet模型 ,利用Shamir门限方案、ElGamal公钥体制、零知识证明等密码技术设计了一个基于这个模型的Mixnet协议 .该协议将同一密文组让不同的两个服务器组进行盲化解密示证和比较 ,从而使得该协议具有 (t - 1,N - 2 ) AA弹性及秘密性、正确性和可验证性等优点 ,同时通信量和计算量方面也少于已知的基于ElGamal公钥体制的可验证Mixnet协议 . 展开更多
关键词 密码 匿名通信 (t N-2)弹性 mixnet 可验证性 秘密性 正确性
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对一种(t,N-2)弹性Mix Net的密码学分析
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作者 李龙海 付少锋 肖国镇 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2007年第6期926-929,934,共5页
分析了Gao等人提出的(t,N-2)弹性Mix Net方案,发现存在严重安全漏洞.主动攻击者利用Elgamal算法的可展性构造具有相关性的密文组,然后通过观察对应明文组的相关性获得输入与输出的对应关系,最终破坏Mix Net的秘密性.两个不同服务器组中... 分析了Gao等人提出的(t,N-2)弹性Mix Net方案,发现存在严重安全漏洞.主动攻击者利用Elgamal算法的可展性构造具有相关性的密文组,然后通过观察对应明文组的相关性获得输入与输出的对应关系,最终破坏Mix Net的秘密性.两个不同服务器组中的恶意服务器可以相互勾结利用共谋攻击使Mix Net输出错误结果,并以不可忽略的概率逃过验证协议的检验.分析结果说明Gao的方案不满足(t,N-2)弹性,且基于该Mix Net的电子投票应用也是不安全的. 展开更多
关键词 匿名通信 mix net 共谋攻击
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An efficient microreactor with continuous serially connected micromixers for the synthesis of superparamagnetic magnetite nanoparticles 被引量:1
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作者 Wenting Fan Fang Zhao +2 位作者 Ming Chen Jian Li Xuhong Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期85-91,共7页
A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM micro... A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM microchannels(V-typed and U-typed)proposed in this work exhibited markedly better mixing performances than the Zigzag and capillary microchannels due to the promotion of Dean vortices.Complete mixing was achieved in the V-typed microchannel in 2.7 s at an inlet Reynolds number of 27.Fe_(3)O_(4) nanoparticles synthesized in a planar glass microreactor with the V-typed microchannel,possessing an average size of 9.3 nm and exhibiting superparamagnetism,had obviously better dispersity and uniformity and higher crystallinity than those obtained in the capillary microreactor.The new CSCM microreactor developed in this work can act as a potent device to intensify the synthesis of similar inorganic nanoparticles via multistep chemical precipitation processes. 展开更多
关键词 MICROREACTOR Continuous serially connected micromixers mixING Nanoparticles
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ARoad Segmentation Model Based on Mixture of the Convolutional Neural Network and the Transformer Network
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作者 Fenglei Xu Haokai Zhao +2 位作者 Fuyuan Hu Mingfei Shen Yifei Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1559-1570,共12页
Convolutional neural networks(CNN)based on U-shaped structures and skip connections play a pivotal role in various image segmentation tasks.Recently,Transformer starts to lead new trends in the image segmentation task... Convolutional neural networks(CNN)based on U-shaped structures and skip connections play a pivotal role in various image segmentation tasks.Recently,Transformer starts to lead new trends in the image segmentation task.Transformer layer can construct the relationship between all pixels,and the two parties can complement each other well.On the basis of these characteristics,we try to combine Transformer pipeline and convolutional neural network pipeline to gain the advantages of both.The image is put into the U-shaped encoder-decoder architecture based on empirical combination of self-attention and convolution,in which skip connections are utilized for localglobal semantic feature learning.At the same time,the image is also put into the convolutional neural network architecture.The final segmentation result will be formed by Mix block which combines both.The mixture model of the convolutional neural network and the Transformer network for road segmentation(MCTNet)can achieve effective segmentation results on KITTI dataset and Unstructured Road Scene(URS)dataset built by ourselves.Codes,self-built datasets and trainable models will be available on https://github.com/xflxfl1992/MCTNet. 展开更多
关键词 Image segmentation TRANSFORMER mix block U-shaped structures
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Identification of Key Links in Electric Power Operation Based-Spatiotemporal Mixing Convolution Neural Network
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作者 Lei Feng Bo Wang +2 位作者 Fuqi Ma Hengrui Ma Mohamed AMohamed 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1487-1501,共15页
As the scale of the power system continues to expand,the environment for power operations becomes more and more complex.Existing risk management and control methods for power operations can only set the same risk dete... As the scale of the power system continues to expand,the environment for power operations becomes more and more complex.Existing risk management and control methods for power operations can only set the same risk detection standard and conduct the risk detection for any scenario indiscriminately.Therefore,more reliable and accurate security control methods are urgently needed.In order to improve the accuracy and reliability of the operation risk management and control method,this paper proposes a method for identifying the key links in the whole process of electric power operation based on the spatiotemporal hybrid convolutional neural network.To provide early warning and control of targeted risks,first,the video stream is framed adaptively according to the pixel changes in the video stream.Then,the optimized MobileNet is used to extract the feature map of the video stream,which contains both time-series and static spatial scene information.The feature maps are combined and non-linearly mapped to realize the identification of dynamic operating scenes.Finally,training samples and test samples are produced by using the whole process image of a power company in Xinjiang as a case study,and the proposed algorithm is compared with the unimproved MobileNet.The experimental results demonstrated that the method proposed in this paper can accurately identify the type and start and end time of each operation link in the whole process of electric power operation,and has good real-time performance.The average accuracy of the algorithm can reach 87.8%,and the frame rate is 61 frames/s,which is of great significance for improving the reliability and accuracy of security control methods. 展开更多
关键词 Security risk management key links identifications electric power operation spatiotemporal mixing convolution neural network Mobilenet network
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Mixed Electric and Magnetic Coupling Design Based on Coupling Matrix Extraction
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作者 XIONG Zhiang ZHAO Ping +2 位作者 FAN Jiyuan WU Zengqiang GONG Hongwei 《ZTE Communications》 2023年第4期85-90,共6页
This paper proposes a design and fine-tuning method for mixed electric and magnetic coupling filters.It derives the quantitative relationship between the coupling coefficients(electric and magnetic coupling,i.e.,EC an... This paper proposes a design and fine-tuning method for mixed electric and magnetic coupling filters.It derives the quantitative relationship between the coupling coefficients(electric and magnetic coupling,i.e.,EC and MC)and the linear coefficients of frequencydependent coupling for the first time.Different from the parameter extraction technique using the bandpass circuit model,the proposed approach explicitly relatesEC and MC to the coupling matrix model.This paper provides a general theoretic framework for computer-aided design and tuning of a mixed electric and magnetic coupling filter based on coupling matrices.An example of a 7th-order coaxial combline filter design is given in the paper,verifying the practical value of the approach. 展开更多
关键词 coupling matrix frequency-dependent coupling mixed electric and magnetic coupling parameter extraction
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Effect of aspect ratio of elliptical stirred vessel on mixing time and flow field characteristics in the absence of baffles
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作者 Yuan Yao Peiqiao Liu +5 位作者 Qian Zhang Zequan Li Benjun Xi Changyuan Tao Yundong Wang Zuohua Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期63-74,共12页
Elliptical tanks were used as an alternative to circular tanks in order to improve mixing efficiency and reduce mixing time in unbaffled stirred tanks(USTs). Five different aspect ratios of elliptical vessels were des... Elliptical tanks were used as an alternative to circular tanks in order to improve mixing efficiency and reduce mixing time in unbaffled stirred tanks(USTs). Five different aspect ratios of elliptical vessels were designed to compare their mixing time and flow field. Computational fluid dynamics(CFD) simulations were performed using the k–ε model to calculate the mixing time and simulate turbulent flow field features, such as streamline shape, velocity distribution, vortex core region distribution, and turbulent kinetic energy(TKE) transfer. Visualization was also carried out to track the tinctorial evolution of the liquid phase. Results reveal that elliptical stirred tanks can significantly improve mixing performance in USTs. Specifically, the mixing time at an aspect ratio of 2.00 is only 45.3% of the one of a circular stirred tank. Furthermore, the secondary flow is strengthened and the vortex core region increases with the increase of aspect ratio. The axial velocity is more sensitive to the aspect ratio than the circumferential and radial velocity. Additionally, the TKE transfer in elliptical vessels is altered. These findings suggest that elliptical vessels offer a promising alternative to circular vessels for enhancing mixing performance in USTs. 展开更多
关键词 mixing time CFD Stirred tank Secondary flow mixing performance
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Evaluation of Nonbreaking Wave-Induced Mixing Parameterization Schemes Based on a One-Dimensional Ocean Model
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作者 TANG Ran HUANG Chuanjiang +1 位作者 DAI Dejun WANG Gang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期567-576,共10页
Surface waves have a considerable effect on vertical mixing in the upper ocean.In the past two decades,the vertical mixing induced through nonbreaking surface waves has been used in ocean and climate models to improve... Surface waves have a considerable effect on vertical mixing in the upper ocean.In the past two decades,the vertical mixing induced through nonbreaking surface waves has been used in ocean and climate models to improve the simulation of the upper ocean.Thus far,several nonbreaking wave-induced mixing parameterization schemes have been proposed;however,no quantitative comparison has been performed among them.In this paper,a one-dimensional ocean model was used to compare the performances of five schemes,including those of Qiao et al.(Q),Hu and Wang(HW),Huang and Qiao(HQ),Pleskachevsky et al.(P),and Ghantous and Babanin(GB).Similar to previous studies,all of these schemes can decrease the simulated sea surface temperature(SST),increase the subsurface temperature,and deepen the mixed layer,thereby alleviating the common thermal deviation problem of the ocean model for upper ocean simulation.Among these schemes,the HQ scheme exhibited the weakest wave-induced mixing effect,and the HW scheme exhibited the strongest effect;the other three schemes exhibited roughly the same effect.In particular,the Q and P schemes exhibited nearly the same effect.In the simulation based on observations from the Ocean Weather Station Papa,the HQ scheme exhibited the best performance,followed by the Q scheme.In the experiment with the HQ scheme,the root-mean-square deviation of the simulated SST from the observations was 0.43℃,and the mixed layer depth(MLD)was 2.0 m.As a contrast,the deviations of the SST and MLD reached 1.25℃ and 8.4 m,respectively,in the experiment without wave-induced mixing. 展开更多
关键词 wave-induced mixing surface waves sea surface temperature mixed layer depth General Ocean Turbulence Model
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Mixed neuroendocrine non-neuroendocrine neoplasms in gastroenteropancreatic tract
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作者 Sebastián Díaz-López Jerónimo Jiménez-Castro +2 位作者 Carlos Enrique Robles-Barraza Carlos Ayala-de Miguel Manuel Chaves-Conde 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1166-1179,共14页
Mixed neuroendocrine non-neuroendocrine neoplasms(MiNENs)are a hetero-geneous group of malignant neoplasms that can settle in the gastroenteropan-creatic tract.They are composed of a neuroendocrine(NE)and a non-NE com... Mixed neuroendocrine non-neuroendocrine neoplasms(MiNENs)are a hetero-geneous group of malignant neoplasms that can settle in the gastroenteropan-creatic tract.They are composed of a neuroendocrine(NE)and a non-NE compo-nent in at least 30%of each tumour.The non-NE component can include different histological combinations of glandular,squamous,mucinous and sarcomatoid phenotypes,and one or both of the components can be low-or high grade malignant.Recent changes in the nomenclature of these neoplasms might lead to great deal of confusion,and the lack of specific clinical trials is the main reason why their management is difficult.The review aims to clarify the definition of MiNEN and analyze available evidence about their diagnosis and treatment options according to their location and extension through careful analysis of the available data.It would be important to reach a general consensus on their diagnosis in order to construct a classification that remains stable over time and facilitates the design of clinical trials that,due to their low incidence,will require long recruitment periods. 展开更多
关键词 mixed neuroendocrine non-neuroendocrine neoplasms mixed adenoneuroendocrine carcinomas mixed tumours Gastroenteropancreatic Treatment Etiology Diagnosis
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Soil properties and not plant factors affect both abundant and rare microbial taxa after thinning in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu
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作者 Wanxia Peng Tongqing Song +5 位作者 Hu Du Feng Wang Fuping Zeng Yang Wang Shulin Chen Yinzhu Chen 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期81-94,共14页
Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communiti... Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communities(i.e.,bacterial,fungal),were evaluated under various thinning treatments in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu using Mi Seq sequencing.Thinning did not significantly change either abundant or rare bacterial and fungal community composition,but affected their alpha diversity.The Shannon–Wiener indexes of rare fungal taxa under medium thinning were significantly lower than in the light thinning(P<0.05 level).Xanthobacteraceae dominated the abundant bacterial taxa,and Saitozyma and Mortierlla the abundant fungal taxa.The most common rare bacterial taxa varied;there was no prevalent rare fungal taxa under different thinnings.In addition,soil available nitrogen,total phosphorus,and p H had significant effects on rare bacterial taxa.Nutrients,especially available phosphorus,but not nitrogen,affected abundant and rare soil fungi.The results indicate that soil properties rather than plant factors affect abundant and rare microbial communities in soils of mixed stands.Thinning,through mediating soil properties,influences both abundant and rare bacterial and fungal communities in the mixed C.lanceolata and S.tzumu stand. 展开更多
关键词 Diversity Abundant taxa Rare taxa THINNING mixed stand
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Assessing mixing uniformity in microreactors via in-line spectroscopy
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作者 Shusaku Asano Shinji Kudo +3 位作者 Taisuke Maki Yosuke Muranaka Kazuhiro Mae Jun-ichiro Hayashi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期119-124,共6页
Mixing behavior is critical for enhancing the selectivity of fast chemical reactions in microreactors.A high Reynolds number(Re)improves the mixing rate and selectivity of the reactions,but some exceptions of increasi... Mixing behavior is critical for enhancing the selectivity of fast chemical reactions in microreactors.A high Reynolds number(Re)improves the mixing rate and selectivity of the reactions,but some exceptions of increasing side product yield with the higher Re have been reported.This study investigated the mixing uniformity in microreactors with in-line UV-vis spectroscopy to clarify the relationship between reaction selectivity and chaotic mixing with the higher Re.A colorization experiment of thymolphthalein in an acidic solution was conducted with an excess acid amount to the base to indicate a non-uniformly mixed region.Non-uniformity significantly increased with Re.At the same time,the degree of mixing,which was measured by a usual decolorization experiment,showed that the mixing rate increased with Re.The in-line analysis of the Villermaux-Dushman reaction during the mixing clarified that side product yield significantly increased with Re at around 300 and then decreased at around 1100.These results suggest the compensation effect between the mixing uniformity and mixing rate on the selectivity of the mixing-sensitive reactions.Faster mixing,characterized by a larger Re,can disturb mixing uniformity and,in some cases,decrease reaction selectivity. 展开更多
关键词 MICROREACTOR Villermaux-Dushman reaction In-line analysis mixING Mass transfer UNIFORMITY
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Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau
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作者 Teng Li Jianfeng Peng +3 位作者 Tsun Fung Au Jingru Li Jinbao Li Yue Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期72-82,共11页
Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-e... Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although S.saltuaria was more sensitive than A.faxoniana.The strong-est correlation was between S.saltuaria chronology and regional mean temperatures from June to November.Based on this relationship,a regional mean temperature from June to November for the period 1605-2016 was constructed.Reconstruction explained 37.3%of the temperature variance during th period 1961-2016.Six major warm periods and five major cold periods were identified.Spectral analysis detected significant interannual and multi-decadal cycles.Reconstruction also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau. 展开更多
关键词 Tree-ring analysis mixed forests DENDROCLIMATOLOGY Qionglai Mountains
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Amino-functionalized UiO-66-doped mixed matrix membranes with high permeation performance and fouling resistance
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作者 Yi Zhang Di Liu +6 位作者 Zhaoli Wang Junjian Yu Yanyin Cheng Wenjing Li Zhe Wang Hongzhe Ni Yuchao Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期68-77,共10页
For the reduction of bovine serum proteins from wastewater,a novel mixed matrix membrane was prepared by functionalizing the substrate material polyaryletherketone(PAEK),followed by carboxyl groups(C-SPAEKS),and then ... For the reduction of bovine serum proteins from wastewater,a novel mixed matrix membrane was prepared by functionalizing the substrate material polyaryletherketone(PAEK),followed by carboxyl groups(C-SPAEKS),and then adding amino-functionalized UiO-66-NH_(2)(Am-UiO-66-NH_(2)).Aminofunctionalization of UiO-66 was accomplished by melamine,followed by an amidation reaction to immobilize Am-UiO-66-NH_(2),which was immobilized on the surface of the membrane as well as in the pore channels,which enhanced the hydrophilicity of the membrane surface while increasing the negative potential of the membrane surface.This nanoparticle-loaded ultrafiltration membrane has good permeation performance,with a pure water flux of up to 482.3 L·m^(-2)·h^(-1) for C-SPAEKS/AmUiO-66-NH_(2) and a retention rate of up to 98.7%for bovine serum albumin(BSA)-contaminated solutions.Meanwhile,after several hydrophilic modifications,the flux recovery of BSA contaminants by this series of membranes increased from 56.2%to 80.55%of pure membranes.The results of ultra-filtration flux time tests performed at room temperature showed that the series of ultrafiltration membranes remained relatively stable over a test time of 300 min.Thus,the newly developed mixed matrix membrane showed potential for high efficiency and stability in wastewater treatment containing bovine serum proteins. 展开更多
关键词 ULTRAFILTRATION mixed matrix membranes Amino functionalization Hydrophilic modification Negatively charged
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Mixed neuroendocrine and adenocarcinoma of gastrointestinal tract:A complex diagnosis and therapeutic challenge
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作者 Santosh Shenoy 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2295-2299,共5页
In this editorial we comment on the manuscript describing a case of adenocarcinoma mixed with a neuroendocrine carcinoma of the gastroesophageal junction.Mixed neuroendocrine and non-neuroendocrine neoplasms of the ga... In this editorial we comment on the manuscript describing a case of adenocarcinoma mixed with a neuroendocrine carcinoma of the gastroesophageal junction.Mixed neuroendocrine and non-neuroendocrine neoplasms of the gastrointestinal system are rare heterogeneous group of tumors characterized by a high malignant potential,rapid growth,and poor prognosis.Due to the rarity of these cancers,the standard therapy is poorly defined.The diagnosis of these tumors is based on combination of morphological features,immunohistochemical and neuroendocrine and epithelial cell markers.Both endocrine and epithelial cell components can act independently of each other and thus,careful grading of each component separately is required.These cancers are aggressive in nature and the potential of each component has paramount importance in the choice of treatment and response.Regardless of the organ of origin,these tumors portend poor prognosis with increased proportion of neuroendocrine component.Multidisciplinary services and strategies are required for the management of these mixed malignancies to provide the best oncological outcomes.The etiopathogenesis of these mixed tumors remains obscure but poses interesting question.We briefly discuss a few salient points in this editorial. 展开更多
关键词 mixed adenocarcinoma and neuroendocrine carcinoma mixed neuroendocrine and non-neuroendocrine neoplasm mixed adeno-neuroendocrine cancer Cell reprograming Tumor plasticity
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Dual-functional poly(2-methyl-2-oxazoline)/poly(2-(dimethylamine)ethyl methacrylate)mixed brushes with switchable protein adsorption and antibacterial properties
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作者 Kang He Liangyu Zhu Yanmei Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期19-30,共12页
Herein,binary mixed brushes consisting of poly(2-methyl-2-oxazoline)(PMOXA)and poly(2-(dimethylamine)ethyl methacrylate)(PDMAEMA)with different chain lengths were fabricated by successive grafting of NH_(2)-terminated... Herein,binary mixed brushes consisting of poly(2-methyl-2-oxazoline)(PMOXA)and poly(2-(dimethylamine)ethyl methacrylate)(PDMAEMA)with different chain lengths were fabricated by successive grafting of NH_(2)-terminated PMOXA and SH-terminated PDMAEMA onto polydopamine-anchored substrates.The mixed-brush coating was characterized by variable-angle spectroscopic ellipsometry,X-ray photoelectron spectroscopy,Fourier transform infrared spectroscopy,zeta potential measurements,water contact angle,and atomic force microscopy.The mixed brushes showed tunable surface charge,wettability,and surface roughness,depending on the degree of PDMAEMA swelling under varying pH and ionic strength(Ⅰ).Then the adsorption behaviors of pepsin,bovine serum albumin(BSA),γ-globulin,and lysozyme,four very different proteins with regard to isoelectric point,on the mixed brushes coating were studied by using fluorescence microscopy and surface plasmon resonance.When the chain length of PDMAEMA was about twice as long as PMOXA,the mixed brushes not only had high adsorption capacity for pepsin,BSA,and y-globulin but also had a desorption efficiency of 86.9%,87.1%,and 93.5%,respectively.It is explained that electrostatic attraction between the protonated PDMAEMA and positively charged acidic proteins(pepsin and BSA,whose isoelectric points were below the pK_(a) of PDMAEMA)would drive the intensive adsorption(at pH 3,I=10^(-3)mol·L^(-1)for pepsin,and pH 5,I=10^(-5)mol·L^(-1)for BSA),while desorption was dominated by the hydrophilic PMOXA when PDMAEMA was shrinking(at pH 7,I=10^(-1)mol·L^(-1)for pepsin,and pH 9,I=10^(-1)mol·L^(-1)for BSA).Furthermore,the isoelectric precipitation led to the adsorption of neutral protein(γ-globulin,whose isoelectric point was near the pK_a of PDMAEMA)at pH 7,I=10^(-5)mol·L^(-1),while electrostatic repulsion and antifouling PMOXA triggered the desorption of y-globulin at pH 3,I-10^(-1)mol·L^(-1).However,alkaline protein(lysozyme,whose isoelectric point was higher than the pK_(a) of PDMAEMA)exhibited slight adsorption on PMOXA/PDMAEMA mixed brushes under test conditions,regardless of whether PMOXA or PDMAEMA occupied the outermost layer.The antibacterial property of the mixed brushes against Escherichia coli was investigated.PMOXA/PDMAEMA mixed brushes showed significant bactericidal activity at pH 3,I=10^(-3)mol·L^(-1),while the rinse of pH 9,I=10^(-1)mol·L^(-1)solution could remove most of the residual bacteria.This work not only enables controlled adsorption of proteins with different isoelectric points but also ensures that the surface of the coating is minimized from bacterial contamination. 展开更多
关键词 Switchable conformation transition Controllable protein adsorption mixed brushes Isoelectric point Antibacterial surface
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On the Application of Mixed Models of Probability and Convex Set for Time-Variant Reliability Analysis
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作者 Fangyi Li Dachang Zhu Huimin Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1981-1999,共19页
In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems... In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of computation.To this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set model.In this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability problem.Further,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis model.The effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem. 展开更多
关键词 mixed uncertainty probability model convex model time-variant reliability analysis
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A unified Minorization-Maximization approach for estimation of general mixture models
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作者 HUANG Xi-fen LIU Deng-ge +1 位作者 ZHOU Yun-peng ZHU Fei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期343-362,共20页
The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling analysis.When the density function of mixed distribution is complicated or the variable dimension is high... The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling analysis.When the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution model.The application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective function.In this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution model.The method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices. 展开更多
关键词 MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation
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Stability Analysis and Performance Evaluation of Additive Mixed-Precision Runge-Kutta Methods
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作者 Ben Burnett Sigal Gottlieb Zachary J.Grant 《Communications on Applied Mathematics and Computation》 EI 2024年第1期705-738,共34页
Additive Runge-Kutta methods designed for preserving highly accurate solutions in mixed-precision computation were previously proposed and analyzed.These specially designed methods use reduced precision for the implic... Additive Runge-Kutta methods designed for preserving highly accurate solutions in mixed-precision computation were previously proposed and analyzed.These specially designed methods use reduced precision for the implicit computations and full precision for the explicit computations.In this work,we analyze the stability properties of these methods and their sensitivity to the low-precision rounding errors,and demonstrate their performance in terms of accuracy and efficiency.We develop codes in FORTRAN and Julia to solve nonlinear systems of ODEs and PDEs using the mixed-precision additive Runge-Kutta(MP-ARK)methods.The convergence,accuracy,and runtime of these methods are explored.We show that for a given level of accuracy,suitably chosen MP-ARK methods may provide significant reductions in runtime. 展开更多
关键词 mixed precision Runge-Kutta methods Additive methods ACCURACY
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Effectively modulating spatial vortex four-wave mixing in a diamond atomic system
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作者 巴诺 姜明奇 +4 位作者 费金友 王丹 蒋海林 王磊 王海华 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期473-478,共6页
Due to the spatial characteristics of orbital angular momentum,vortex fields can be applied in the fields of quantum storage and quantum information.We study the realization of spatially modulated vortex fields based ... Due to the spatial characteristics of orbital angular momentum,vortex fields can be applied in the fields of quantum storage and quantum information.We study the realization of spatially modulated vortex fields based on four-wave mixing in a four-level atomic system with a diamond structure.The intensity and spiral phase of the vortex field are effectively transferred to the generated four-wave mixing field.By changing the detuning of the probe field,the phase and intensity of the generated vertex four-wave mixing field can be changed.When the probe field takes a large detuning value,the spatial distribution of the intensity and phase of the vertex four-wave mixing field can be effectively tuned by adjusting the Rabi frequency or detuning value of the coupled field.At the same time,we also provide a detailed explanation based on the dispersion relationship,and the results agree well with our simulation results. 展开更多
关键词 coherent optical effects four-wave mixing orbital angular momentum
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