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MicroRNAs in blood and cerebrospinal fluid as diagnostic biomarkers of multiple sclerosis and to monitor disease progression 预览
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作者 Bridget Martinez Philip V.Peplow 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期606-619,共14页
Multiple sclerosis is a chronic autoimmune disease of the central nervous system.It is the main cause of non-traumatic neurological disability in young adults.Multiple sclerosis mostly affects people aged 20–50 years... Multiple sclerosis is a chronic autoimmune disease of the central nervous system.It is the main cause of non-traumatic neurological disability in young adults.Multiple sclerosis mostly affects people aged 20–50 years;however,it can occur in young children and much older adults.Factors identified in the distribution of MS include age,gender,genetics,environment,and ethnic background.Multiple sclerosis is usually associated with progressive degrees of disability.The disease involves demyelination of axons of the central nervous system and causes brain and spinal cord neuronal loss and atrophy.Diagnosing multiple sclerosis is based on a patient’s medical history including symptoms,physical examination,and various tests such as magnetic resonance imaging,cerebrospinal fluid and blood tests,and electrophysiology.The disease course of multiple sclerosis is not well correlated with the biomarkers presently used in clinical practice.Blood-derived biomarkers that can detect and distinguish the different phenotypes in multiple sclerosis may be advantageous in personalized treatment with disease-modifying drugs and to predict response to treatment.The studies reviewed have shown that the expression levels of a large number of miRNAs in peripheral blood,serum,exosomes isolated from serum,and cerebrospinal fluid are altered in multiple sclerosis and can distinguish the disease phenotypes from each other.Further studies are warranted to independently validate these findings so that individual or pairs of miRNAs in serum or cerebrospinal fluid can be used as potential diagnostic markers for adult and pediatric multiple sclerosis and for monitoring disease progression and response to therapy. 展开更多
关键词 clinically isolated syndrome CSF disease PROGRESSION EXOSOMES humans microRNA multiple SCLEROSIS PERIPHERAL blood PHENOTYPES serum
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Relationship between MRI perfusion and clinical severity in multiple sclerosis 预览
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作者 Maria Marcella Laganà Laura Pelizzari Francesca Baglio 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期646-652,共7页
Perfusion alterations within several brain regions have been shown in multiple sclerosis patients using different magnetic resonance imaging(MRI)techniques.Furthermore,MRI-derived brain perfusion metrics have been inv... Perfusion alterations within several brain regions have been shown in multiple sclerosis patients using different magnetic resonance imaging(MRI)techniques.Furthermore,MRI-derived brain perfusion metrics have been investigated in association with multiple sclerosis phenotypes,physical disability,and cognitive impairment.However,a review focused on these aspects is still missing.Our aim was to review all the studies investigating the relationship between perfusion MRI and clinical severity during the last fifteen years to understand the clinical relevance of these findings.Perfusion differences among phenotypes were observed both with 1.5T and 3T scanners,with progressive multiple sclerosis presenting with lower perfusion values than relapsing-remitting multiple sclerosis patients.However,only 3T scanners showed a statistically significant distinction.Controversial results about the association between MRI-derived perfusion metrics and physical disability scores were found.However,the majority of the studies showed that lower brain perfusion and longer transit time are associated with more severe physical disability and worse cognitive performances. 展开更多
关键词 brain PERFUSION cerebral blood flow cognition DISABILITY magnetic resonance imaging MRI multiple SCLEROSIS PHENOTYPES PROGRESSIVE relapsing remitting
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Ependymal cells and multiple sclerosis: proposing a relationship 预览
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作者 Dale Hatrock Nina Caporicci-nucci Jo Anne Stratton 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期263-264,共2页
Multiple sclerosis (MS) currently affects ~2.5 million people worldwide. MS is typically diagnosed in young adults and is usually not fatal, meaning people live long lives with MS. Affected individuals usually suffer ... Multiple sclerosis (MS) currently affects ~2.5 million people worldwide. MS is typically diagnosed in young adults and is usually not fatal, meaning people live long lives with MS. Affected individuals usually suffer from progressive physical and/or cognitive disability, often including fatigue (89.6%), depression (53.9%), memory loss (49.0%), motor or sensory dysfunction (76.4%, 70.4%) and urinary incontinence (50.8%). 展开更多
关键词 MULTIPLE SCLEROSIS RELATIONSHIP DYSFUNCTION
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Metabolic checkpoints in neurodegenerative T helper 17 (TH17) and neuroregenerative regulatory T (Treg) cells as new therapeutic targets for multiple sclerosis 预览
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作者 Hongxing Shen James A. Bonner Lewis Zhichang Shi 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期267-269,共3页
The central nervous system (CNS) is an immune-privileged site with tightly-regulated immune responses, a concept proposed by Nobel Laureate Sir Peter Medawar in 1960. Under physiological conditions, only a few T lymph... The central nervous system (CNS) is an immune-privileged site with tightly-regulated immune responses, a concept proposed by Nobel Laureate Sir Peter Medawar in 1960. Under physiological conditions, only a few T lymphocytes conducting immunosurveillance can infiltrate the CNS. 展开更多
关键词 METABOLIC CHECKPOINTS multiple SCLEROSIS CNS
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Cerebrospinal fluid neurogranin as a new player in prion disease diagnosis and prognosis 预览
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作者 Anna Villar-Piqué Inga Zerr Franc Llorens 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第5期861-862,共2页
Neurogranin (Ng) and its role as Alzheimer’s disease (AD) biomarker: Ng is a calmodulin-binding protein mainly expressed in cerebral structures such as the cortex,hippocampus and striatum.It is mainly located in the ... Neurogranin (Ng) and its role as Alzheimer’s disease (AD) biomarker: Ng is a calmodulin-binding protein mainly expressed in cerebral structures such as the cortex,hippocampus and striatum.It is mainly located in the dendritic processes,particularly in post-synaptic compartments,but also in the cytosolic compartment,being likely involved in the regulation of the intracellular calcium-calmodulin signaling pathway (Represa et al.,1990).In the last decade,a plethora of studies have demonstrated that cerebrospinal fluid (CSF) Ng is increased in AD patients and in individuals with an ADlike CSF profile (Kester et al.,2015a).This increase seems to be disease-specific because other neurodegenerative conditions including frontotemporal dementia,Lewy body dementia,Parkinson’s disease,progressive supranuclear palsy,multiple system atrophy or Huntington’s disease,present CSF Ng concentrations similar to controls (Wellington et al.,2016).Ng levels in CSF appear to be elevated in mild cognitive impairment (MCI)-affected individuals who progress to AD and are highly related to memory and cognitive function (Kester et al.,2015a;Tarawneh et al.,2016),which indicates that this protein may serve as an early AD biomarker with diagnostic utility in pre-dementia disease stages,and with prognostic utility to predict cognitive decline and MCI-to-AD conversion. 展开更多
关键词 Represa CEREBROSPINAL FLUID MULTIPLE SYSTEM
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User Assisted Cooperative Relaying in Beamspace Massive MIMO NOMA Based Systems for Millimeter Wave Communications 预览
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作者 Jaipreet Kaur Maninder Lal Singh 《中国通信:英文版》 SCIE CSCD 2019年第6期103-113,共11页
A novel scheme‘user assisted cooperative relaying in beamspace massive multiple input multiple output(M-MIMO)non-orthogonal multiple access(NOMA)system’has been proposed to improve coverage area,spectrum and energy ... A novel scheme‘user assisted cooperative relaying in beamspace massive multiple input multiple output(M-MIMO)non-orthogonal multiple access(NOMA)system’has been proposed to improve coverage area,spectrum and energy efficiency for millimeter wave(mmWave)communications.A downlink system for M users,where base station(BS)is equipped with beamforming lens antenna structure having NRF radio frequency(RF)chains,has been considered.A dynamic cluster of users is formed within a beam and the intermediate users(in that cluster)between beam source and destination(user)act as relaying stations.By the use of successive interference cancellation(SIC)technique of NOMA within a cluster,the relaying stations relay the symbols with improved power to the destination.For maximizing achievable sum rate,transmit precoding and dynamic power allocation for both intra and inter beam power optimization are implemented.Simulations for performance evaluation are carried out to validate that the proposed system outperforms the conventional beamspace M-MIMO NOMA system for mmWave communications in terms of spectrum and energy efficiency. 展开更多
关键词 cooperative RELAYING system(CRS) millimeter wave(mmWave) MASSIVE MULTIPLE input MULTIPLE output(M-MIMO) non-orthogonal MULTIPLE access(NOMA) power allocation sum rate
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Frameworks of Non-Orthogonal Multiple Access Techniques in Cognitive Radio Communication Systems 预览
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作者 Prabhat Thakur Alok Kumar +2 位作者 S Pandit G Singh S N Satashia 《中国通信:英文版》 SCIE CSCD 2019年第6期129-149,共21页
Recently,the increasing demand of radio spectrum for the next generation communication systems due to the explosive growth of applications appetite for bandwidths has led to the problem of spectrum scarcity.The potent... Recently,the increasing demand of radio spectrum for the next generation communication systems due to the explosive growth of applications appetite for bandwidths has led to the problem of spectrum scarcity.The potential approaches among the proposed solutions to resolve this issue are well explored cognitive radio(CR)technology and recently introduced non-orthogonal multiple access(NOMA)techniques.Both the techniques are employed for efficient spectrum utilization and assure the significant improvement in the spectral efficiency.Further,the significant improvement in spectral efficiency can be achieved by combining both the techniques.Since the CR is well-explored technique as compared to that of the NOMA in the field of communication,therefore it is worth and wise to implement this technique over the CR.In this article,we have presented the frameworks of NOMA implementation over CR as well as the feasibility of proposed frameworks.Further,the differences between proposed CR-NOMA and conventional CR frameworks are discussed.Finally,the potential issues regarding the implementation of CR-NOMA are explored. 展开更多
关键词 cognitive radio channel state information non-orthogonal MULTIPLE ACCESS power DIVISION MULTIPLE ACCESS superposition-coding successive-interference-cancellation
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MIMO-WiMAX system incorporated with diverse transformation for 5G applications
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作者 Lavish KANSAL Vishal SHARMA Jagjit Singh MALHOTRA 《中国光电子学前沿:英文版》 EI CSCD 2019年第3期296-310,共15页
Wireless systems and standards are now progressing toward the implementation of fifth generation (5G) to combat with an expected and explosive growth of demands of wireless services in future. Consequently, wireless i... Wireless systems and standards are now progressing toward the implementation of fifth generation (5G) to combat with an expected and explosive growth of demands of wireless services in future. Consequently, wireless interoperability for microwave access (WiMAX) with orthogonal frequency division multiplexing (OFDM) technology at its physical layer is being utilized for the uplink and downlink transmission to afford the high spectral efficiency in fading environments. However, the 5G implementation requires additional improvements to meet the futuristic stress. This work proposes an innovative solution that combines WiMAX system with multiple input multiple output (MIMO) technology to meet the required elevated data rates as desired by the growing application needs of 5G. MIMO is capable to fulfil the vision of 5G to realize a huge number of base stations equipped with a large number of terminals to be served in the same time-frequency resource without severe inter-user interference. Furthermore, the proposed system is demon- strated incorporation with discrete wavelet transform (DWT), and fractional Fourier transforms (FrFTs) in the physical layer of the WiMAX system. The evaluated outcomes exemplify a considerable improvement in bit error rate (BER) performance in contrast with the earlier reported work. 展开更多
关键词 wireless interoperability for microwave access (WiMAX) ORTHOGONAL frequency division MULTIPLEXING (OFDM) MULTIPLE input MULTIPLE output (MIMO) fast FOURIER TRANSFORM (FFT) discrete wavelet TRANSFORM (DWT) fractional FOURIER TRANSFORM (FrFT)
A Case Report of Double Malignancy—Recurrent Nasopharyngeal Carcinoma and Adenocarcinoma of the Uterus 预览
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作者 Ihab E Ali Farid Razali +2 位作者 Sobani Din Tang Phing Phing K. Y. Loh 《耳鼻喉(英文)》 2019年第6期198-203,共6页
Multiple primary malignancies (MPMs) is a rare clinical condition where a patient is diagnosed with two or more cancers around the same time. Published literature reported the incidence of multiple primaries is in the... Multiple primary malignancies (MPMs) is a rare clinical condition where a patient is diagnosed with two or more cancers around the same time. Published literature reported the incidence of multiple primaries is in the range of 2% - 17%. The risk factors for MPMs are smoking, chronic alcoholism, genetic factors and previous treatment of cancer using radiotherapy that may lead to the development of other cancer. This case report describes a rare and unfortunate case of middle-aged Malaysian Chinese lady diagnosed with adenocarcinoma of the uterus and around the same time she had a recurrent nasopharyngeal carcinoma which was first diagnosed and treated 11 years ago. There were no clear risk factors identified in her and she defaulted follow up which eventually led to a fatal complication in which the nasopharyngeal cancer caused massive bleeding in her and she finally succumbed to the complication despite emergency resuscitations. 展开更多
关键词 Multiple PRIMARY MALIGNANCIES
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Is China’s Economy Overestimated?*——Counter-Evidence from the Underground Economy 预览
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作者 王永兴 《中国经济学人:英文版》 2019年第3期30-43,共14页
Over the past four decades of reform and opening up since 1978, China’s GDP has been growing at 9.5% on an annual average basis. While some scholars believe that China’s economic growth is systematically overestimat... Over the past four decades of reform and opening up since 1978, China’s GDP has been growing at 9.5% on an annual average basis. While some scholars believe that China’s economic growth is systematically overestimated, this paper carries out an estimation of China’s underground economy and finds that due to the existence of the underground economy, China’s real GDP is systematically underestimated. China’s official GDP statistics generally reflect a real picture of its economic growth. The size of China’s underground economy is significantly influenced by total electricity consumption, the selfemployed ratio, labor participation rate and money supply. These findings are of great significance for policy-making. 展开更多
关键词 underground economy LATENT variable CASH ratio MODEL MULTIPLE indicators MULTIPLE causes (MIMIC) MODEL
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Temporal variability of visibility and its parameterizations in Ningbo,China
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作者 Jingjing Zhang Lei Tong +4 位作者 Chenghui Peng Huiling Zhang Zhongwen Huang Jun He Hang Xiao 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期372-382,共11页
Simultaneous and continuous measurements of visibility, meteorological parameters and air pollutants were carried out at a suburban site in Ningbo from June 1, 2013 to May 31,2015. The characteristics of visibility an... Simultaneous and continuous measurements of visibility, meteorological parameters and air pollutants were carried out at a suburban site in Ningbo from June 1, 2013 to May 31,2015. The characteristics of visibility and their relationships with air pollutants and meteorological factors were investigated using multiple statistical methods. Daily visibility ranged from 0.6 to 34.1 km, with a mean value of 11.8 km. During the 2-year experiment,43.4% of daily visibility was found to be less than 10.0 km and only 9.2% was greater than 20.0 km. Visibility was lower in winter with a frequency of 53.4% in the range of 0.0–5.0 km.Annual visibility had an obvious diurnal variation, with the lowest and highest visibility being 7.5 km at approximately 06:00 local time and 15.6 km at approximately 14:00 local time, respectively. Multiple correspondence analysis(MCA) indicated that the different ranges of visibility were significantly affected by different levels of pollutants and meteorological conditions. Based on the analyses, visibility was found to be an exponential function of PM2.5 concentrations within a certain range of relative humidity. Thus, nonlinear models combining multiple linear regressions with exponential regression were subsequently developed using the data collected from June 2014 to May 2015, and the data from June 2013 to May 2014 was used to evaluate the performance of the model. It was demonstrated that the derived models can quantitatively describe the relationships between visibility, air quality and meteorological parameters in Ningbo. 展开更多
关键词 VISIBILITY MULTIPLE CORRESPONDENCE analysis(MCA) MULTIPLE NON-LINEAR regression
Establishment and verification of a surgical prognostic model for cervical spinal cord injury without radiological abnormality 预览
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作者 Jie Wang Shuai Guo +2 位作者 Xuan Cai Jia-Wei Xu Hao-Peng Li 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第4期713-720,共8页
Some studies have suggested that early surgical treatment can effectively improve the prognosis of cervical spinal cord injury without radiological abnormality,but no research has focused on the development of a progn... Some studies have suggested that early surgical treatment can effectively improve the prognosis of cervical spinal cord injury without radiological abnormality,but no research has focused on the development of a prognostic model of cervical spinal cord injury without radiological abnormality.This retrospective analysis included 43 patients with cervical spinal cord injury without radiological abnormality.Seven potential factors were assessed:age,sex,external force strength causing damage,duration of disease,degree of cervical spinal stenosis,Japanese Orthopaedic Association score,and physiological cervical curvature.A model was established using multiple binary logistic regression analysis.The model was evaluated by concordant profiling and the area under the receiver operating characteristic curve.Bootstrapping was used for internal validation.The prognostic model was as follows:logit(P)=-25.4545+21.2576VALUE+1.2160SCORE-3.4224TIME,where VALUE refers to the Pavlov ratio indicating the extent of cervical spinal stenosis,SCORE refers to the Japanese Orthopaedic Association score(0–17)after the operation,and TIME refers to the disease duration(from injury to operation).The area under the receiver operating characteristic curve for all patients was 0.8941(95%confidence interval,0.7930–0.9952).Three factors assessed in the predictive model were associated with patient outcomes:a great extent of cervical stenosis,a poor preoperative neurological status,and a long disease duration.These three factors could worsen patient outcomes.Moreover,the disease prognosis was considered good when logit(P)≥-2.5105.Overall,the model displayed a certain clinical value.This study was approved by the Biomedical Ethics Committee of the Second Affiliated Hospital of Xi’an Jiaotong University,China(approval number:2018063)on May 8,2018. 展开更多
关键词 nerve REGENERATION SURGICAL prognostic model CERVICAL SPINAL cord injury retrospective study MULTIPLE binary logistic regression analysis BOOTSTRAPPING internal validation MULTIPLE imputations CERVICAL SPINAL stenosis duration of disease Pavlov ratio neural REGENERATION
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QSM-IDM -A novel quadrature spatial modulation based on interleaving division multiplexing for multiple antenna system 预览
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作者 Sherif K. El Dyasti Esam A.A. Hagras Hadia El-Hennawy 《数字通信与网络:英文版》 2019年第3期183-188,共6页
Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless communication systems. The main concept of QSM is t... Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless communication systems. The main concept of QSM is to extend the spatial constellation of the conventional Spatial Modulation (SM) in both the in-phase and quadrature components of the data symbol. In this paper, because QSM-based on Interleaxdng Division Multiplexing (IDM) has not been introduced in the literature as a multiple antenna system, we introduced a novel scheme, called QSM system based on Interleaving Division Multiplexing (QSM-IDM). The antenna sets are also applied to a spreader, before being used to assign an antenna number for information transmission. Analysis and simulations for a flat fading channel show that the proposed QSM-IDM method significantly outperforms the original QSM system with the same data rate, while maintaining a relatively acceptable complexity. The obtained simulation results show that the conducted analysis yields significant improvements for the accuracy of the proposed scheme, with satisfactory complexity. 展开更多
关键词 Interleaver DIVISION MULTIPLEXING (IDM) MULTIPLE Input MULTIPLE Output (MIMO) Spatial MODULATION (SM) QUADRATURE Spatial MODULATION (QSM)
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Internal Transactions for Multiple Risky Assets 预览
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作者 Qiong Zhang Shuang Chen 《统计学期刊(英文)》 2019年第1期85-99,共15页
Most of the articles about insider trading assume that there is only one risky asset in the market. On the basis of these papers, this thesis is mainly divided into three parts to study the situation of multiple risky... Most of the articles about insider trading assume that there is only one risky asset in the market. On the basis of these papers, this thesis is mainly divided into three parts to study the situation of multiple risky assets in the market. In the first part, the situation of multiple risky assets in the market when two transactions are in progress is studied and then, the equilibrium when the market requires the internal traders to disclose the trading volume after each transaction is analyzed. In the second part, the equilibrium of multi-period based on the two phases of transaction is derived. The third part is the summary of the paper. 展开更多
关键词 INSIDER TRADING MULTIPLE Risky ASSETS MULTI-PERIOD Noise TRADER
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Wideband MIMO Radar Waveform Optimization Based on Range Profile 预览
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作者 Qun Zhang Yishuai Gong Yijun Chen 《北京理工大学学报:英文版》 EI CAS 2019年第1期137-145,共9页
Aiming at the signal bandwidth design problem for multi-target imaging task,a kind of multiple input multiple output(MIMO)radar waveform design method is proposed.At first,the closed-loop feedback between the range pr... Aiming at the signal bandwidth design problem for multi-target imaging task,a kind of multiple input multiple output(MIMO)radar waveform design method is proposed.At first,the closed-loop feedback between the range profile and the signal bandwidth,which can design the minimum bandwidth of a transmitting signal that can distinguish each scatterer of the target in range direction,is established.Then,considering the request of beam pattern and the bandwidth limitation,a waveform optimization model is established and solved.Therefore,the multi-target observation and the dynamic adjustment of the signal bandwidth are accomplished.In the end,the simulation results prove the performance of the algorithm in a low SNR circumstance. 展开更多
关键词 MULTIPLE input MULTIPLE output(MIMO)radar COGNITION WAVEFORM design RANGE profile RANGE RESOLUTION
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Design of Power Amplifier for mm Wave 5G and Beyond 预览
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作者 LI Lianming SI Jiachen CHEN Linhui 《南京航空航天大学学报:英文版》 EI CSCD 2019年第4期579-588,共10页
With targets of cost reduction per bit and high energy efficiency,5G and beyond call for innovation in the mmWave transmitter architecture and the power amplifier(PA)circuit.To illustrate these points,this paper first... With targets of cost reduction per bit and high energy efficiency,5G and beyond call for innovation in the mmWave transmitter architecture and the power amplifier(PA)circuit.To illustrate these points,this paper firstly explains the benefits and design implications of the hybrid beamforming structure in terms of the mmWave spectrum characteristics,energy efficiency,data rate,communication capacity,coverage and implementation technology choices.Then after reviewing the techniques to improve the power amplifier(PA)output power and efficiency,the design considerations and test results of 60 GHz and 90 GHz mmWave PAs in bulk complementary metal oxide semiconductor(CMOS)process are shown. 展开更多
关键词 5G and BEYOND 6G BEAMFORMING COMPLEMENTARY metal oxide semiconductor(CMOS) mmWave MULTIPLE input MULTIPLE output(MIMO) power amplifier TRANSMITTER
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Resonant multiple wave solutions to some integrable soliton equations
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作者 刘建根 杨小军 冯忆颖 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第11期92-98,共7页
To transform the exponential traveling wave solutions to bilinear differential equations, a sufficient and necessary condition is proposed. Motivated by the condition, we extend the results to the(2+1)-dimensional Kad... To transform the exponential traveling wave solutions to bilinear differential equations, a sufficient and necessary condition is proposed. Motivated by the condition, we extend the results to the(2+1)-dimensional Kadomtsev–Petviashvili(KP) equation, the(3+1)-dimensional generalized Kadomtsev–Petviashvili(g-KP) equation, and the B-type Kadomtsev–Petviashvili(BKP) equation. Aa a result, we obtain some new resonant multiple wave solutions through the parameterization for wave numbers and frequencies via some linear combinations of exponential traveling waves. Finally, these new resonant type solutions can be displayed in graphs to illustrate the resonant behaviors of multiple wave solutions. 展开更多
关键词 linear superposition principle resonant multiple wave solutions (2+1)-dimensional Kadomtsev–Petviashvili(KP) equation (3+1)-dimensional g-KP and BKP equations
Evaluating Suitability of Multiple Precipitation Products for the Lancang River Basin 预览
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作者 TANG Xiongpeng ZHANG Jianyun +7 位作者 WANG Guoqing YANG Qinli YANG Yanqing GUAN Tiesheng LIU Cuishan JIN Junliang LIU Yanli BAO Zhenxin 《中国地理科学:英文版》 SCIE CSCD 2019年第1期37-57,共21页
Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sour... Global reanalysis precipitation products could provide valuable meteorological information for flow forecasting in poorly gauged areas, helping to overcome a long-standing challenge in the field. But not all data sources are suitable for all regions or perform the same way in hydrological modeling, so it is essential to test the suitability of precipitation products before applying them. In this study, five widely used global high-resolution precipitation products-Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation of Water Resources(APHRODITE), National Centers for Environmental Prediction Climate Forecast System Reanalysis(NCEP-CFSR), Climate Hazards Group InfraRed Precipitation with Station Data(CHIRPS), China Gauge-based Daily Precipitation Analysis developed by China Meteorological Administration(CMA) and Agricultural Model Intercomparison and Improvement Project based on the NASA Modern-Era Retrospective Analysis for Research and Applications(AgMERRA)-were evaluated using statistical methods and a hydrological approach for their suitability for the Lancang River Basin. The results indicated that APHRODITE, CMA, AgMERRA and CHIRPS were more accurate precipitation indicators than NCEP-CFSR in terms of the multiyear average and seasonal spatial distribution pattern, all of the CHIRPS, Ag MERRA and APHRODITE perform better than CMA and NCEP-CFSR at the small, medium and high precipitation intensities ranges in subbasin11 and sunbabsin46. All five products performed better in subbasin46(a low-altitude region) than in subbasin11(a high-altitude region) on the daily and monthly scales. In addition to NCEP-CFSR, the other four products all presented encouraging potential for streamflow simulation at daily(Yunjinghong) and monthly(Yunjinghong, Jiuzhou and Gajiu) scale. Hydrological simulations forced with APHRODITE were the best of the five for the Yunjinghong station in capturing daily and monthly measured streamflow. Except for NCEP-CFSR, all products were very good for hydrologic 展开更多
关键词 MULTIPLE PRECIPITATION PRODUCTS SUITABILITY evaluation the Lancang River BASIN
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Weather induced subtidal flows through multiple inlets of an arctic microtidal lagoon 预览
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作者 Chunyan Li Kevin M.Boswell +2 位作者 Nazanin Chaichitehrani Wei Huang Renhao Wu 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期1-16,共16页
Estuarine processes in the arctic lagoons are among the least studied but important subjects, especially considering the rapid warming of arctic water which may change the length of ice-free period in the summer. In t... Estuarine processes in the arctic lagoons are among the least studied but important subjects, especially considering the rapid warming of arctic water which may change the length of ice-free period in the summer. In this paper, wind-driven exchange flows in the micro-tidal Elson Lagoon of northern Alaska with multiple inlets of contrasting widths and depths are studied with in situ observations, statistical analysis, numerical experiments, a regression model on the basis of dynamics, and remote sensing data. Water velocity profiles were obtained from a bottom deployed acoustic Doppler current profiler(ADCP) in the northwestern Eluitkak Pass connecting the Beaufort Sea to the Elson Lagoon during a 4.9 day ice-free period in the summer of 2013. The subtidal flow is found correlated with wind(R~2 value ~96%). Frequently occurring east, northeast and north winds from the arctic atmospheric high-and low-pressure systems push water from the Beaufort Sea into the lagoon through the wide inlets on the eastern side of the lagoon, resulting in an outward flow against the wind at the narrow northwestern inlet. The counter-wind flow is a result of an uneven wind forcing acting through the asymmetric inlets and depth,an effect of 'torque' or vorticity. Under northwest wind, the exchange flow at the northwestern inlet reverses its direction, with inward flows through the upwind northwestern inlet and outward flows through the downwind eastern inlets. A regression model is established based on the momentum equations and Taylor series expansions. The model is used to predict flows in July and August of 2015 and July of 2017, supported by available Landsat satellite images. About 73%–80% of the time the flows at Eluitkak Pass are out of Elson Lagoon for the summer of 2015 and 2017. Numerical experiments are conducted to corroborate the findings and illustrate the effects under various wind conditions. A quasi-steady state balance between wind force and surface pressure gradient is confirmed. 展开更多
关键词 WIND-DRIVEN FLOWS MULTIPLE INLETS micro-tidal numerical model experiments counter-wind FLOWS quasi-steady state
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Synchronous resection of esophageal cancer and other organ malignancies:A systematic review 预览
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作者 Dimitrios Papaconstantinou Diamantis I Tsilimigras +7 位作者 Dimitrios Moris Adamantios Michalinos Aikaterini Mastoraki Efstratia Mpaili Natasha Hasemaki Anargyros Bakopoulos Dimitrios Filippou Dimitrios Schizas 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第26期3438-3449,共12页
BACKGROUND Neoplasms arising in the esophagus may coexist with other solid organ or gastrointestinal tract neoplasms in 6%to 15%of patients.Resection of both tumors synchronously or in a staged procedure provides the ... BACKGROUND Neoplasms arising in the esophagus may coexist with other solid organ or gastrointestinal tract neoplasms in 6%to 15%of patients.Resection of both tumors synchronously or in a staged procedure provides the best chances for long-term survival.Synchronous resection of both esophageal and second primary malignancy may be feasible in a subset of patients;however,literature on this topic remains rather scarce.AIM To analyze the operative techniques employed in esophageal resections combined with gastric,pancreatic,lung,colorectal,kidney and liver resections and define postoperative outcomes in each case.METHODS We conducted a systematic review according to PRISMA guidelines.We searched the Medline database for cases of patients with esophageal tumors coexisting with a second primary tumor located in another organ that underwent synchronous resection of both neoplasms.All English language articles deemed eligible for inclusion were accessed in full text.Exclusion criteria included:(1)Hematological malignancies;(2)Head/neck/pharyngeal neoplasms;(3)Second primary neoplasms in the esophagus or the gastroesophageal junction;(4)Second primary neoplasms not surgically excised;and(5)Preclinical studies.Data regarding the operative strategy employed,perioperative outcomes and longterm outcomes were extracted and analyzed using descriptive statistics.RESULTS The systematic literature search yielded 23 eligible studies incorporating a total of 117 patients.Of these patients,71%had a second primary neoplasm in the stomach.Those who underwent total gastrectomy had a reconstruction using either a colonic(n=23)or a jejunal(n=3)conduit while for those who underwent gastric preserving resections(i.e.,non-anatomic/wedge/distal gastrectomies)a conventional gastric pull-up was employed.Likewise,in cases of patients who underwent esophagectomy combined with pancreaticoduodenectomy(15%of the cohort),the decision to preserve part of the stomach or not dictated the reconstruction method(whether by a gastric pullup or a colonic/jej 展开更多
关键词 ESOPHAGECTOMY Esophageal neoplasm Second PRIMARY Multiple PRIMARY CONCURRENT neoplasms Management
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