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Genome-wide identification of functional enhancers and their potential roles in pig breeding 被引量:2
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作者 Yinqiao Wu Yuedong Zhang +8 位作者 Hang Liu Yun Gao Yuyan Liu Ling Chen Lu Liu David M.Irwin Chunhui Hou Zhongyin Zhou Yaping Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第6期1690-1702,共13页
Background:The pig is an economically important livestock species and is a widely applied large animal model in medical research.Enhancers are critical regulatory elements that have fundamental functions in evolution,... Background:The pig is an economically important livestock species and is a widely applied large animal model in medical research.Enhancers are critical regulatory elements that have fundamental functions in evolution,development and disease.Genome-wide quantification of functional enhancers in the pig is needed.Results:We performed self-transcribing active regulatory region sequencing(STARR-seq)in the porcine kidney epithelial PK15 and testicular ST cell lines,and reliably identified 2576 functional enhancers.Most of these enhancers were located in repetitive sequences and were enriched within silent and lowly expressed genes.Enhancers poorly overlapped with chromatin accessibility regions and were highly enriched in chromatin with the repressive histone modification H3K9me3,which is different from predicted pig enhancers detected using ChIP-seq for H3K27ac or/and H3K4me1 modified histones.This suggests that most pig enhancers identified with STARR-seq are endogenously repressed at the chromatin level and may function during cell type-specific development or at specific developmental stages.Additionally,the PPP3CA gene is associated with the loin muscle area trait and the QKI gene is associated with alkaline phosphatase activity that may be regulated by distal functional enhancers.Conclusions:In summary,we generated the first functional enhancer map in PK15 and ST cells for the pig genome and highlight its potential roles in pig breeding. 展开更多
关键词 BREEDING Functional enhancers PIG STARR-seq
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Enhancers and hindrances to doctor-nurse interdisciplinary collaborative practice in Nigeria
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作者 Ijeoma L. Okoronkwo John E. Anieche +1 位作者 Anthonia U. Chinweuba Afam C. Ndu 《Open Journal of Nursing》 2013年第2期169-177,共9页
The purpose of this study was to identify factors that enhance and hinder interdisciplinary collaborative practice (ICP) among doctors and nurses at the Nnamdi Azikiwe teaching hospital, Nnewi, southeast Nigeria. The ... The purpose of this study was to identify factors that enhance and hinder interdisciplinary collaborative practice (ICP) among doctors and nurses at the Nnamdi Azikiwe teaching hospital, Nnewi, southeast Nigeria. The study was a cross-sectional descriptive survey and the quantitative method of data collection was employed. The population was all doctors irrespective of area of specialty and all nurses employed and working in the hospital as at the time of study. Proportionate stratified and convenience sampling methods were used to select study participants according to their categories. Using validated structured questionnaire, data were collected from 110 doctors and 95 nurses in the teaching hospital on their perception on ICP and factors that enhance/hinder ICP. Data were analyzed using both descriptive and inferential statistics. Specifically, frequencies, percentages, standard deviation and graphic presentation were used for descriptive analysis of scores while the unpaired t test of mean score using Graph Pad Prism, Version 5.30 was used to determine the influence of profession, gender, and years of experience on perception of ICP at 0.05 level of significance. The study found that both doctors and nurses have positive perception on ICP. Their years of experience have significant influence on their perception. Clear individual roles and good working relationships enhance ICP while giving priority to professional status rather than expertise was seen as a prominent hindrance to ICP. The study recommends collaborative continuing education for doctors and nurses to enhance ICP in patient care. In addition, the inclusion of interdisciplinary collaborative practice programmme into the curriculum of medical and nursing students (where it does not exist) would go a long way to strengthen ICP and decrease hindrances when they graduate. 展开更多
关键词 enhancers Hindrances Doctor-Nurse INTERDISCIPLINARY COLLABORATIVE Practice Nnamdi Azikiwe UNIVERSITY Teaching HOSPITAL Nnewi NIGERIA
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Novel chemical permeation enhancers for transdermal drug delivery 被引量:3
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作者 Yang Chen Peng Quan +2 位作者 Xiaochang Liu Manli Wang Liang Fang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2014年第2期51-64,共14页
Transdermal drug delivery has been accepted as a potential non-invasive route of drug administration,with advantages of prolonged therapeutic action,decreased side effect,easy use and better patient compliance.However... Transdermal drug delivery has been accepted as a potential non-invasive route of drug administration,with advantages of prolonged therapeutic action,decreased side effect,easy use and better patient compliance.However,development of transdermal products is primarily hindered by the low permeability of the skin.To overcome this barrier effect,numerous new chemicals have been synthesized as potential permeation enhancers for transdermal drug delivery.In this review,we presented an overview of the investigations in this field,and further implications on selection or design of suitable permeation enhancers for transdermal drug delivery were also discussed. 展开更多
关键词 TRANSDERMAL Permeation enhancer MECHANISM
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Influence of chemical penetration enhancers on skin permeability of ellagic acid-loaded niosomes 被引量:1
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作者 Varaporn Buraphacheep Junyaprasert Pratyawadee Singhsa Anchalee Jintapattanakit 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2013年第2期110-117,共8页
This study aimed to develop niosomes of ellagic acid(EA),a potent antioxidant phytochemical substance,for dermal delivery and to investigate the influence of chemical penetration enhancers on the physicochemical prope... This study aimed to develop niosomes of ellagic acid(EA),a potent antioxidant phytochemical substance,for dermal delivery and to investigate the influence of chemical penetration enhancers on the physicochemical properties of EA-loaded niosomes.The EA niosomes were prepared by reverse phase evaporation method using Span 60,Tween 60 and cholesterol as vesicle forming agents and Solulan C24 as a steric stabilizer.Polyethylene glycol 400(PEG)was used as a solubilizer while dimethylsulfoxide(DMSO)or Nmethyl-2-pyrrolidone(NMP)was used as a skin penetration enhancer.It was found that the mean particle sizes of EA-loaded niosomes were in the range of 312e402 nm with PI values of lower than 0.4.The niosomes were determined to be spherical multilamellar vesicles as observed by transmission electron microscope and optical microscopy.All niosomes were stable after 4 months storage at 4C.In vitro skin permeation through human epidermis revealed that the skin enhancers affected the penetration of EA from the niosomes at 24 h.The DMSO niosomes showed the highest EA amount in epidermis;whereas the NMP niosomes had the highest EA amount in the acceptor medium.Concomitantly,the skin distribution by confocal laser scanning microscopy showed the high fluorescence intensity of the DMSO niosomes and NMP niosomes at a penetration depth of between 30e90 mm(the epidermis layer)and 90e120 mm(the dermis layer)under the skin,respectively.From the results,it can be concluded that the DMSO niosomes are suitable for epidermis delivery of EA while the NMP niosomes can be used for dermis delivery of EA. 展开更多
关键词 Ellagic acid NIOSOMES Chemical penetration enhancer Skin permeation Dermal delivery
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The enhancing effect and promoting mechanisms of the stereoisomeric monoterpene alcohol esters as enhancers for drugs with different physicochemical properties 被引量:1
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作者 Heping Wang Yan Li +7 位作者 Chunyan Wang Jing Wang Bo Ren Xiaona Li Mingzhu Li Dandan Geng Chensi Wu Ligang Zhao 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2022年第1期139-152,共14页
To explore the structure-activity connections of amphiphilic permeation enhancers containing the length of the hydrophobic chains as well as the properties of the polar head,O-acylgeraniol and O-acylnerol derivatives ... To explore the structure-activity connections of amphiphilic permeation enhancers containing the length of the hydrophobic chains as well as the properties of the polar head,O-acylgeraniol and O-acylnerol derivatives were synthesized from geraniol/nerol(cis-isomer of geraniol) and pharmaceutical excipient acids in this research. Their promotion of the percutaneous absorption of three drugs as the model, flurbiprofen(FP), isosorbide dinitrate(ISDN) and donepezil(DNP), which were selected based on their physicochemical properties,was tested by in vitro skin penetration and in vivo. Molecular simulation, ATR-FTIR, CLSM and histological observation were implement to evaluate the mode of action of the enhancers.The results indicated that(E)-3,7-dimethyl-2,6-octadien-1-yl tetradecanoate(GER-C14, trans-)achieved the highest enhancement ability for the three drugs;additionally, the in vivo results obtained were in good correlation with the in vitro data. Molecular docking results suggested that enhancers loosen the hydrogen bonds between ceramides, and the results of molecular simulation indicated that GER-C14, NER-C14 could insert into the middle of the lipid bilayer to form an independent phase. According to ATR-FTIR and histological evaluation, the enhancers extracted lipids and influenced the protein region, thereby disturbing the skin array. In addition, CLSM described the dynamic effects of enhancers on lipids between stratum corneum(SC) cells. In conclusion, GER-C14 had a better penetration promotion effect, which broadened our understanding of stereoisomeric penetration enhancers. 展开更多
关键词 O-acylgeraniol derivatives O-acylnerol derivatives Transdermal drug delivery system In vitro and in vivo correlation Enhancing mechanism
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The untold story between enhancers and skeletal muscle development
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作者 ZHANG Yong-sheng LU Dan +2 位作者 LIU Yu-wen YI Guo-qiang TANG Zhong-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第9期2137-2149,共13页
Currently,enhancers have key transcriptional regulatory roles in muscle development.Skeletal muscle formation involves various molecules,and in animals,enhancers are one of the main types of transcriptional regulatory... Currently,enhancers have key transcriptional regulatory roles in muscle development.Skeletal muscle formation involves various molecules,and in animals,enhancers are one of the main types of transcriptional regulatory regions that are of great importance to regulate myogenic gene expression.In muscle development,enhancers can generate enhancer RNAs(eRNAs)that are involved in the regulation of gene transcription.The regulation of gene expression by eRNAs offers great potential in improving animal production traits.Herein we comprehensively review the roles of enhancers in muscle formation and its potential function in skeletal muscle development.This review will describe the future application of enhancers in skeletal muscle development and discuss the prospects that enhancer studies offer for agriculture,biotechnology,and animal breeding. 展开更多
关键词 ANIMAL ENHANCER eRNA skeletal muscle growth and development
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Potential of Essential Oils as Alternative Permeation Enhancers for Transdermal Delivery
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作者 Jayshree Mahanty Sofi Haamid Rasheed +2 位作者 Sudhir Kumar Harjeet Singh Alok Sharma 《World Journal of Traditional Chinese Medicine》 CAS CSCD 2023年第3期258-269,共12页
Transdermal drug delivery plays a significant part in the drug delivery system when compared to other routes of drug administration.The function of the stratum corneum(SC)is a barrier.Recently,numerous methods have be... Transdermal drug delivery plays a significant part in the drug delivery system when compared to other routes of drug administration.The function of the stratum corneum(SC)is a barrier.Recently,numerous methods have been thrived to improve the perforation of drugs across the skin.The most effective method is to use enhancers since these agents enhance skin permeability.Natural penetration enhancers like essential oils demonstrate higher enhancement activity and are more widely accepted than synthetic penetration enhancers.High potential in the expansion and interaction with the SC intercellular lipids has led to an increasing interest in these oils as penetration enhancers.This article gives an overview of a few essential oils,including their mode of action and important parameters for permeation improvement.The present work can provide essential oils as alternative enhancers,and this could be useful in transdermal administration. 展开更多
关键词 Essential oil natural permeation enhancers SKIN stratum corneum transdermal drug delivery
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Steering Against Wind: A New Network of NamiRNAs and Enhancers 被引量:1
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作者 ying liang qingping zou wenqiang yu 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2017年第5期331-337,共7页
MicroRNAs (miRNAs) are a class of endogenous non-coding RNAs with regulatory functions. Traditionally, miRNAs are thought to play a negative regulatory role in the cytoplasm by binding to the YUTR of target genes to... MicroRNAs (miRNAs) are a class of endogenous non-coding RNAs with regulatory functions. Traditionally, miRNAs are thought to play a negative regulatory role in the cytoplasm by binding to the YUTR of target genes to degrade mRNA or inhibit translation. However, it remains a challenge to interpret the potential function of many miRNAs located in the nucleus. Recently, we reported a new type of miRNAs present in the nucleus, which can activate gene expres- sion by binding to the enhancer, and named them nuclear activating miRNAs (NamiRNAs). The discovery of NamiRNAs showcases a complementary regulatory mechanism of miRNA, demon- strating their differential roles in the nucleus and cytoplasm. Here, we reviewed miRNAs in nucleus to better understand the function of NamiRNAs in their interactions with the enhancers. Accord- ingly, we propose a NamiRNA--enhancer-target gene activation network model to better under- stand the crosstalk between NamiRNAs and enhancers in regulating gene transcription. Moreover, we hypothesize that NamiRNAs may be involved in cell identity or cell fate determina- tion during development, although further study is needed to elucidate the underlying mechanisms in detail. 展开更多
关键词 Nuclear activating miRNAs Tissue-specific enhancers Transcriptional gene activa-tion Cell identity Cell fate
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Liquid injectivity in a SAG foam process:Effect of permeability
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作者 Jia-Kun Gong Yuan Wang +4 位作者 Ridhwan-Zhafri B.Kamarul Bahrim Raj-Deo Tewari Mohammad-Iqbal Mahamad Amir Rouhi Farajzadeh William Rossen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期302-314,共13页
Foam is utilized in enhanced oil recovery and CO_(2) sequestration.Surfactant-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in fa... Foam is utilized in enhanced oil recovery and CO_(2) sequestration.Surfactant-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in facilities.Our previous studies with similar permeability cores show that during SAG injection,several banks occupy the area near the well where fluid exhibits distinct behaviour.However,underground reservoirs are heterogeneous,often layered.It is crucial to understand the effect of permeability on fluid behaviour and injectivity in a SAG process.In this work,coreflood experiments are conducted in cores with permeabilities ranging from 16 to 2300 mD.We observe the same sequence of banks in cores with different permeabilities.However,the speed at which banks propagate and their overall mobility can vary depending on permeability.At higher permeabilities,the gas-dissolution bank and the forced-imbibition bank progress more rapidly during liquid injection.The total mobilities of both banks decrease with permeability.By utilizing a bank-propagation model,we scale up our experimental findings and compare them to results obtained using the Peaceman equation.Our findings reveal that the liquid injectivity in a SAG foam process is misestimated by conventional simulators based on the Peaceman equation.The lower the formation permeability,the greater the error. 展开更多
关键词 Foam Enhanced oil recovery Surfactant-alternating-gas INJECTIVITY PERMEABILITY
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Evaluating Ignition and Combustion Performance with Al-Metal- Organic Frameworks and Nano-Aluminum in HTPB Fuel
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作者 Sri Nithya Mahottamananda Yash Pal +2 位作者 Yarravarapu Sai Sriram Subha S Djalal Trache 《火炸药学报》 EI CAS CSCD 北大核心 2024年第5期413-421,I0003,共10页
Incorporating aluminum metal-organic frameworks(Al-MOFs)as energetic additives for solid fuels presents a promising avenue for enhancing combustion performance.This study explores the potential benefits of Al-MOF(MIL-... Incorporating aluminum metal-organic frameworks(Al-MOFs)as energetic additives for solid fuels presents a promising avenue for enhancing combustion performance.This study explores the potential benefits of Al-MOF(MIL-53(Al))energetic additive on the combustion performance of hydroxyl-terminated polybutadiene(HTPB)fuel.The HTPB-MOF fuel samples were manufactured using the vacuum-casting technique,followed by a comprehensive evaluation of their ignition and combustion properties using an opposed flow burner(OFB)setup utilizing gaseous oxygen as an oxidizer.To gauge the effectiveness of Al-MOFs as fuel additives,their impact is compared with that of nano-aluminum(nAl),another traditional additive in HTPB fuel.The results indicate that the addition of 15%(mass fraction)nAl into HTPB resulted in the shortest ignition delay time(136 ms),demonstrating improved ignition performance compared to pure HTPB(273 ms).The incorporation of Al-MOF in HTPB also reduced ignition delay times to 227 ms and 189 ms,respectively.Moreover,under high oxidizer mass flux conditions(79—81 kg/(m^(2)s)),HTPB fuel with 15%nAl exhibited a substantial 83.2%increase in regression rate compared to the baseline HTPB fuel,highlighting the positive influence of nAl on combustion behavior.In contrast,HTPB-MOF with a 15%Al-MOF additive showed a 32.7%increase in regression rate compared to pure HTPB.These results suggest that HTPB-nAl outperforms HTPB-MOF in terms of regression rates,indicating a more vigorous and rapid burning behavior. 展开更多
关键词 IGNITION combustion enhancement MOF HTPB regression rate
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Broadband Dual-Input Doherty Power Amplifier Design Based on a Simple Adaptive Power Dividing Ratio Function
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作者 Dai Zhijiang Zhong Kang +2 位作者 Li Mingyu Pang Jingzhou Jin Yi 《China Communications》 SCIE CSCD 2024年第5期97-112,共16页
In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency poi... In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency points can be characterized by a polynomial.And in the practical test,the coefficients of SSF can be determined by measuring a small number of data points of input power.Same as other dualinput DPAs,the proposed approach can also achieve high output power and back-off efficiency in a broadband operation band by adjusting the power distribution ratio flexibly.Finally,a 1.5-2.5 GHz highefficiency dual-input Doherty power amplifier is implemented according to this approach.The test results show that the peak power is 48.6-49.7d Bm,and the 6-d B back-off efficiency is 51.0-67.0%,and the saturation efficiency is 52.4-74.6%.The digital predistortion correction is carried out at the frequency points of 1.8/2.1GHz,and the adjacent channel power ratio is lower than-54.5d Bc.Simulation and experiment results can verify the effectiveness and correctness of the proposed method. 展开更多
关键词 BROADBAND doherty power amplifier dualinput efficiency enhancement load modulation
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Finesse measurement for high-power optical enhancement cavity
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作者 陆心怡 柳兴 +3 位作者 田其立 王焕 汪嘉俊 颜立新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期414-421,共8页
Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the a... Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range(FSR) modulation method is proposed and compared with three other finesse measurement methods, i.e., the fast-switching cavity ring-down(CRD) method, the rapidly swept-frequency(SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications. 展开更多
关键词 optical enhancement cavity finesse measurement cavity ring-down ringing effect
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Ground threat prediction-based path planning of unmanned autonomous helicopter using hybrid enhanced artificial bee colony algorithm
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作者 Zengliang Han Mou Chen +1 位作者 Haojie Zhu Qingxian Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期1-22,共22页
Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning system.Aiming to reduce the influence of non-complete ground threat information on UAH path planning,a gro... Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning system.Aiming to reduce the influence of non-complete ground threat information on UAH path planning,a ground threat prediction-based path planning method is proposed based on artificial bee colony(ABC)algorithm by collaborative thinking strategy.Firstly,a dynamic threat distribution probability model is developed based on the characteristics of typical ground threats.The dynamic no-fly zone of the UAH is simulated and established by calculating the distribution probability of ground threats in real time.Then,a dynamic path planning method for UAH is designed in complex environment based on the real-time prediction of ground threats.By adding the collision warning mechanism to the path planning model,the flight path could be dynamically adjusted according to changing no-fly zones.Furthermore,a hybrid enhanced ABC algorithm is proposed based on collaborative thinking strategy.The proposed algorithm applies the leader-member thinking mechanism to guide the direction of population evolution,and reduces the negative impact of local optimal solutions caused by collaborative learning update strategy,which makes the optimization performance of ABC algorithm more controllable and efficient.Finally,simulation results verify the feasibility and effectiveness of the proposed ground threat prediction path planning method. 展开更多
关键词 UAH Path planning Ground threat prediction Hybrid enhanced Collaborative thinking
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PAPS: Progressive Attention-Based Pan-sharpening
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作者 Yanan Jia Qiming Hu +2 位作者 Renwei Dian Jiayi Ma Xiaojie Guo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期391-404,共14页
Pan-sharpening aims to seek high-resolution multispectral(HRMS) images from paired multispectral images of low resolution(LRMS) and panchromatic(PAN) images, the key to which is how to maximally integrate spatial and ... Pan-sharpening aims to seek high-resolution multispectral(HRMS) images from paired multispectral images of low resolution(LRMS) and panchromatic(PAN) images, the key to which is how to maximally integrate spatial and spectral information from PAN and LRMS images. Following the principle of gradual advance, this paper designs a novel network that contains two main logical functions, i.e., detail enhancement and progressive fusion, to solve the problem. More specifically, the detail enhancement module attempts to produce enhanced MS results with the same spatial sizes as corresponding PAN images, which are of higher quality than directly up-sampling LRMS images.Having a better MS base(enhanced MS) and its PAN, we progressively extract information from the PAN and enhanced MS images, expecting to capture pivotal and complementary information of the two modalities for the purpose of constructing the desired HRMS. Extensive experiments together with ablation studies on widely-used datasets are provided to verify the efficacy of our design, and demonstrate its superiority over other state-of-the-art methods both quantitatively and qualitatively. Our code has been released at https://github.com/JiaYN1/PAPS. 展开更多
关键词 High-resolution multispectral image image fusion pan-sharpening progressive enhancement
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Atomically Substitutional Engineering of Transition Metal Dichalcogenide Layers for Enhancing Tailored Properties and Superior Applications
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作者 Zhaosu Liu Si Yin Tee +1 位作者 Guijian Guan Ming‑Yong Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期248-284,共37页
Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor behav... Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor behavior.Binary MX2 layers with different metal and/or chalcogen elements have similar structural parameters but varied optoelectronic properties,providing opportunities for atomically substitutional engineering via partial alteration of metal or/and chalcogenide atoms to produce ternary or quaternary TMDs.The resulting multinary TMD layers still maintain structural integrity and homogeneity while achieving tunable(opto)electronic properties across a full range of composition with arbitrary ratios of introduced metal or chalcogen to original counterparts(0–100%).Atomic substitution in TMD layers offers new adjustable degrees of freedom for tailoring crystal phase,band alignment/structure,carrier density,and surface reactive activity,enabling novel and promising applications.This review comprehensively elaborates on atomically substitutional engineering in TMD layers,including theoretical foundations,synthetic strategies,tailored properties,and superior applications.The emerging type of ternary TMDs,Janus TMDs,is presented specifically to highlight their typical compounds,fabrication methods,and potential applications.Finally,opportunities and challenges for further development of multinary TMDs are envisioned to expedite the evolution of this pivotal field. 展开更多
关键词 Transition metal dichalcogenides Atomic substitution Tailored structure Tunable bandgap Enhanced applications
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Recent advances in protein conformation sampling by combining machine learning with molecular simulation
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作者 唐一鸣 杨中元 +7 位作者 姚逸飞 周运 谈圆 王子超 潘瞳 熊瑞 孙俊力 韦广红 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期80-87,共8页
The rapid advancement and broad application of machine learning(ML)have driven a groundbreaking revolution in computational biology.One of the most cutting-edge and important applications of ML is its integration with... The rapid advancement and broad application of machine learning(ML)have driven a groundbreaking revolution in computational biology.One of the most cutting-edge and important applications of ML is its integration with molecular simulations to improve the sampling efficiency of the vast conformational space of large biomolecules.This review focuses on recent studies that utilize ML-based techniques in the exploration of protein conformational landscape.We first highlight the recent development of ML-aided enhanced sampling methods,including heuristic algorithms and neural networks that are designed to refine the selection of reaction coordinates for the construction of bias potential,or facilitate the exploration of the unsampled region of the energy landscape.Further,we review the development of autoencoder based methods that combine molecular simulations and deep learning to expand the search for protein conformations.Lastly,we discuss the cutting-edge methodologies for the one-shot generation of protein conformations with precise Boltzmann weights.Collectively,this review demonstrates the promising potential of machine learning in revolutionizing our insight into the complex conformational ensembles of proteins. 展开更多
关键词 machine learning molecular simulation protein conformational space enhanced sampling
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Effects of fracture evolution and non-Darcy flow on the thermal performance of enhanced geothermal system in 3D complex fractured rock
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作者 Yachen Xie Jianxing Liao +2 位作者 Pengfei Zhao Kaiwen Xia Cunbao Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期443-459,共17页
In fractured geothermal reservoirs,the fracture networks and internal fluid flow behaviors can significantly impact the thermal performance.In this study,we proposed a non-Darcy rough discrete fracture network(NR-DFN)... In fractured geothermal reservoirs,the fracture networks and internal fluid flow behaviors can significantly impact the thermal performance.In this study,we proposed a non-Darcy rough discrete fracture network(NR-DFN)model that can simultaneously consider the fracture evolution and non-Darcy flow dynamics in studying the thermo-hydro-mechanical(THM)coupling processes for heat extraction in geothermal reservoir.We further employed the model on the Habanero enhanced geothermal systems(EGS)project located in Australia.First,our findings illustrate a clear spatial-temporal variation in the thermal stress and pressure perturbations,as well as uneven spatial distribution of shear failure in 3D fracture networks.Activated shear failure is mainly concentrated in the first fracture cluster.Secondly,channeling flow have also been observed in DFNs during heat extraction and are further intensified by the expansion of fractures driven by thermal stresses.Moreover,the combined effect of non-Darcy flow and fracture evolution triggers a rapid decline in the resulting heat rate and temperature.The NR-DFN model framework and the Habanero EGS's results illustrate the importance of both fracture evolution and non-Darcy flow on the efficiency of EGS production and have the potential to promote the development of more sustainable and efficient EGS operations for stakeholders. 展开更多
关键词 Coupled THM model Non-Darcy flow Deformable DFN Enhanced geothermal systems
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Enhanced structural damage behavior of liquid-filled tank by reactive material projectile impact
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作者 Jianwen Xie Yuanfeng Zheng +4 位作者 Zhenyang Liu Chengzhe Liu Aoxin Liu Pengwan Chen Haifu Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期211-229,共19页
A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles(RMPs) impacting liquid-filled tanks,and the corresponding hydrodynamic ram(HRAM) was s... A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles(RMPs) impacting liquid-filled tanks,and the corresponding hydrodynamic ram(HRAM) was studied in detail.PTFE/Al/W RMPs with steel-like and aluminum-like densities were prepared by a pressing/sintering process.The projectiles impacted a liquid-filled steel tank with front aluminum panel at approximately 1250 m/s.The corresponding cavity evolution characteristics and HRAM pressure were recorded by high-speed camera and pressure acquisition system,and further compared to those of steel and aluminum projectiles.Significantly different from the conical cavity formed by the inert metal projectile,the cavity formed by the RMP appeared as an ellipsoid with a conical front.The RMPs were demonstrated to enhance the radial growth velocity of cavity,the global HRAM pressure amplitude and the front panel damage,indicating the enhanced HRAM and structural damage behavior.Furthermore,combining the impact-induced fragmentation and deflagration characteristics,the cavity evolution of RMPs under the combined effect of kinetic energy impact and chemical energy release was analyzed.The mechanism of enhanced HRAM pressure induced by the RMPs was further revealed based on the theoretical model of the initial impact wave and the impulse analysis.Finally,the linear correlation between the deformation-thickness ratio and the non-dimensional impulse for the front panel was obtained and analyzed.It was determined that the enhanced near-field impulse induced by the RMPs was the dominant reason for the enhanced structural damage behavior. 展开更多
关键词 Reactive material projectile Hydrodynamic ram Enhanced structural damage Liquid-filled tank Impact
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Hyperspectral image super resolution using deep internal and self-supervised learning
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作者 Zhe Liu Xian-Hua Han 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期128-141,共14页
By automatically learning the priors embedded in images with powerful modelling ca-pabilities,deep learning-based algorithms have recently made considerable progress in reconstructing the high-resolution hyperspectral... By automatically learning the priors embedded in images with powerful modelling ca-pabilities,deep learning-based algorithms have recently made considerable progress in reconstructing the high-resolution hyperspectral(HR-HS)image.With previously collected large-amount of external data,these methods are intuitively realised under the full supervision of the ground-truth data.Thus,the database construction in merging the low-resolution(LR)HS(LR-HS)and HR multispectral(MS)or RGB image research paradigm,commonly named as HSI SR,requires collecting corresponding training triplets:HR-MS(RGB),LR-HS and HR-HS image simultaneously,and often faces dif-ficulties in reality.The learned models with the training datasets collected simultaneously under controlled conditions may significantly degrade the HSI super-resolved perfor-mance to the real images captured under diverse environments.To handle the above-mentioned limitations,the authors propose to leverage the deep internal and self-supervised learning to solve the HSI SR problem.The authors advocate that it is possible to train a specific CNN model at test time,called as deep internal learning(DIL),by on-line preparing the training triplet samples from the observed LR-HS/HR-MS(or RGB)images and the down-sampled LR-HS version.However,the number of the training triplets extracted solely from the transformed data of the observation itself is extremely few particularly for the HSI SR tasks with large spatial upscale factors,which would result in limited reconstruction performance.To solve this problem,the authors further exploit deep self-supervised learning(DSL)by considering the observations as the unlabelled training samples.Specifically,the degradation modules inside the network were elaborated to realise the spatial and spectral down-sampling procedures for transforming the generated HR-HS estimation to the high-resolution RGB/LR-HS approximation,and then the reconstruction errors of the observations were formulated for measuring the network modelling performance.By consolidating the DIL and DSL into a unified deep framework,the authors construct a more robust HSI SR method without any prior training and have great potential of flexible adaptation to different settings per obser-vation.To verify the effectiveness of the proposed approach,extensive experiments have been conducted on two benchmark HS datasets,including the CAVE and Harvard datasets,and demonstrate the great performance gain of the proposed method over the state-of-the-art methods. 展开更多
关键词 computer vision deep learning deep neural networks HYPERSPECTRAL image enhancement
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A New Encrypted Traffic Identification Model Based on VAE-LSTM-DRN
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作者 Haizhen Wang Jinying Yan Na Jia 《Computers, Materials & Continua》 SCIE EI 2024年第1期569-588,共20页
Encrypted traffic identification pertains to the precise acquisition and categorization of data from traffic datasets containing imbalanced and obscured content.The extraction of encrypted traffic attributes and their... Encrypted traffic identification pertains to the precise acquisition and categorization of data from traffic datasets containing imbalanced and obscured content.The extraction of encrypted traffic attributes and their subsequent identification presents a formidable challenge.The existing models have predominantly relied on direct extraction of encrypted traffic data from imbalanced datasets,with the dataset’s imbalance significantly affecting the model’s performance.In the present study,a new model,referred to as UD-VLD(Unbalanced Dataset-VAE-LSTM-DRN),was proposed to address above problem.The proposed model is an encrypted traffic identification model for handling unbalanced datasets.The encoder of the variational autoencoder(VAE)is combined with the decoder and Long-short term Memory(LSTM)in UD-VLD model to realize the data enhancement processing of the original unbalanced datasets.The enhanced data is processed by transforming the deep residual network(DRN)to address neural network gradient-related issues.Subsequently,the data is classified and recognized.The UD-VLD model integrates the related techniques of deep learning into the encrypted traffic recognition technique,thereby solving the processing problem for unbalanced datasets.The UD-VLD model was tested using the publicly available Tor dataset and VPN dataset.The UD-VLD model is evaluated against other comparative models in terms of accuracy,loss rate,precision,recall,F1-score,total time,and ROC curve.The results reveal that the UD-VLD model exhibits better performance in both binary and multi classification,being higher than other encrypted traffic recognition models that exist for unbalanced datasets.Furthermore,the evaluation performance indicates that the UD-VLD model effectivelymitigates the impact of unbalanced data on traffic classification.and can serve as a novel solution for encrypted traffic identification. 展开更多
关键词 Data enhancement LSTM deep residual network VAE
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