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Coupled multiphysical model for investigation of influence factors in the application of microbially induced calcite precipitation 被引量:1
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作者 Xuerui Wang Pavan Kumar Bhukya +1 位作者 Dali Naidu Arnepalli Shuang Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2232-2249,共18页
The study presents a comprehensive coupled thermo-bio-chemo-hydraulic(T-BCH)modeling framework for stabilizing soils using microbially induced calcite precipitation(MICP).The numerical model considers relevant multiph... The study presents a comprehensive coupled thermo-bio-chemo-hydraulic(T-BCH)modeling framework for stabilizing soils using microbially induced calcite precipitation(MICP).The numerical model considers relevant multiphysics involved in MICP,such as bacterial ureolytic activities,biochemical reactions,multiphase and multicomponent transport,and alteration of the porosity and permeability.The model incorporates multiphysical coupling effects through well-established constitutive relations that connect parameters and variables from different physical fields.It was implemented in the open-source finite element code OpenGeoSys(OGS),and a semi-staggered solution strategy was designed to solve the couplings,allowing for flexible model settings.Therefore,the developed model can be easily adapted to simulate MICP applications in different scenarios.The numerical model was employed to analyze the effect of various factors,including temperature,injection strategies,and application scales.Besides,a TBCH modeling study was conducted on the laboratory-scale domain to analyze the effects of temperature on urease activity and precipitated calcium carbonate.To understand the scale dependency of MICP treatment,a large-scale heterogeneous domain was subjected to variable biochemical injection strategies.The simulations conducted at the field-scale guided the selection of an injection strategy to achieve the desired type and amount of precipitation.Additionally,the study emphasized the potential of numerical models as reliable tools for optimizing future developments in field-scale MICP treatment.The present study demonstrates the potential of this numerical framework for designing and optimizing the MICP applications in laboratory-,prototype-,and field-scale scenarios. 展开更多
关键词 MULTIPHYSICS Microbially induced calcite precipitation(MICP) Coupled thermo-bio-chemo-hydraulic(TBCH) model OpenGeoSys(OGS) Influence factors
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Implications for fault reactivation and seismicity induced by hydraulic fracturing
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作者 Zi-Han Sun Ming-Guang Che +3 位作者 Li-Hong Zhu Shu-Juan Zhang Ji-Yuan Lu Chang-Yu Jin 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1081-1098,共18页
Evaluating the physical mechanisms that link hydraulic fracturing(HF) operations to induced earthquakes and the anticipated form of the resulting events is significant in informing subsurface fluid injection operation... Evaluating the physical mechanisms that link hydraulic fracturing(HF) operations to induced earthquakes and the anticipated form of the resulting events is significant in informing subsurface fluid injection operations. Current understanding supports the overriding role of the effective stress magnitude in triggering earthquakes, while the impact of change rate of effective stress has not been systematically addressed. In this work, a modified critical stiffness was brought up to investigate the likelihood, impact,and mitigation of induced seismicity during and after hydraulic fracturing by developing a poroelastic model based on rate-and-state fraction law and linear stability analysis. In the new criterion, the change rate of effective stress was considered a key variable to explore the evolution of this criterion and hence the likelihood of instability slip of fault. A coupled fluid flow-deformation model was used to represent the entire hydraulic fracturing process in COMSOL Multiphysics. The possibility of triggering an earthquake throughout the entire hydraulic fracturing process, from fracturing to cessation, was investigated considering different fault locations, orientations, and positions along the fault. The competition between the effects of the magnitude and change rate of effective stress was notable at each fracturing stage. The effective stress magnitude is a significant controlling factor during fracturing events, with the change rate dominating when fracturing is suddenly started or stopped. Instability dominates when the magnitude of the effective stress increases(constant injection at each fracturing stage) and the change rate of effective stress decreases(the injection process is suddenly stopped). Fracturing with a high injection rate, a fault adjacent to the hydraulic fracturing location and the position of the junction between the reservoir and fault are important to reduce the Coulomb failure stress(CFS) and enhance the critical stiffness as the significant disturbance of stresses at these positions in the coupled process. Therefore,notable attention should be given to the injection rate during fracturing, fault position, and position along faults as important considerations to help reduce the potential for induced seismicity. Our model was verified and confirmed using the case of the Longmaxi Formation in the Sichuan Basin, China, in which the reported microseismic data were correlated with high critical stiffness values. This work supplies new thoughts of the seismic risk associated with HF engineering. 展开更多
关键词 Hydraulic fracturing Coulomb failure stress Rate-and-state fraction model Linear stability analysis Critical stiffness Seismically induced fault
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Using induced pluripotent stem cells as a tool for modelling carcinogenesis 被引量:5
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作者 Emma L Curry Mohammad Moad +1 位作者 Craig N Robson Rakesh Heer 《World Journal of Stem Cells》 SCIE CAS 2015年第2期461-469,共9页
Cancer is a highly heterogeneous group of diseases that despite improved treatments remain prevalent accounting for over 14 million new cases and 8.2 million deaths per year. Studies into the process of carcinogenesis... Cancer is a highly heterogeneous group of diseases that despite improved treatments remain prevalent accounting for over 14 million new cases and 8.2 million deaths per year. Studies into the process of carcinogenesis are limited by lack of appropriate models for the development and pathogenesis of the disease based on human tissues. Primary culture of patient samples can help but is difficult to grow for a number of tissues. A potential opportunity to overcome these barriers is based on the landmark study by Yamanaka which demonstrated the ability of four factors;Oct4, Sox2, Klf4, and c-Myc to reprogram human somatic cells in to pluripotency. These cells were termed induced pluripotent stem cells(i PSCs) and display characteristic properties of embryonic stem cells. This technique has a wide range of potential uses including disease modelling, drug testing and transplantation studies. Interestingly i PSCs also share a number of characteristics with cancer cells including self-renewal and proliferation, expression of stem cell markers and altered metabolism. Recently, i PSCs have been generated from a number of human cancer cell lines and primary tumour samples from a range of cancers in an attempt to recapitulate the development of cancer and interrogate the underlying mechanisms involved. This review will outline the similarities between the reprogramming process and carcinogenesis, and how these similarities have been exploited to generate i PSC models for a number of cancers. 展开更多
关键词 induced PLURIPOTENT STEM CELLS CANCER model REPROGRAMMING
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Fault activation and induced seismicity in geological carbon storage--Lessons learned from recent modeling studies 被引量:7
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作者 Jonny Rutqvist Antonio P. Rinaldi +5 位作者 Frederic Cappa Pierre Jeanne Alberto Mazzoldi Luca Urpi Yves Guglielmi Victor Vilarrasa 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第6期789-804,共16页
In the light of current concerns related to induced seismicity associated with geological carbon sequestration(GCS),this paper summarizes lessons learned from recent modeling studies on fault activation,induced seismi... In the light of current concerns related to induced seismicity associated with geological carbon sequestration(GCS),this paper summarizes lessons learned from recent modeling studies on fault activation,induced seismicity,and potential for leakage associated with deep underground carbon dioxide(CO2) injection.Model simulations demonstrate that seismic events large enough to be felt by humans require brittle fault properties and continuous fault permeability allowing pressure to be distributed over a large fault patch to be ruptured at once.Heterogeneous fault properties,which are commonly encountered in faults intersecting multilayered shale/sandstone sequences,effectively reduce the likelihood of inducing felt seismicity and also effectively impede upward CO2leakage.A number of simulations show that even a sizable seismic event that could be felt may not be capable of opening a new flow path across the entire thickness of an overlying caprock and it is very unlikely to cross a system of multiple overlying caprock units.Site-specific model simulations of the In Salah CO2storage demonstration site showed that deep fractured zone responses and associated microseismicity occurred in the brittle fractured sandstone reservoir,but at a very substantial reservoir overpressure close to the magnitude of the least principal stress.We conclude by emphasizing the importance of site investigation to characterize rock properties and if at all possible to avoid brittle rock such as proximity of crystalline basement or sites in hard and brittle sedimentary sequences that are more prone to injection-induced seismicity and permanent damage. 展开更多
关键词 Carbon dioxide(CO_2) injection Fault rupture induced seismicity Ground motion LEAKAGE modelING
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Model Test Study on Ice Induced Vibration of A Compliant Conical Structure 被引量:3
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作者 黄焱 史庆增 宋安 《China Ocean Engineering》 SCIE EI 2005年第3期443-456,共14页
The problem of ice induced vibration is common to ocean engineering of cold region countries. To study the ice induced vibration of a compliant conical structure, a series of model tests have been performed and some b... The problem of ice induced vibration is common to ocean engineering of cold region countries. To study the ice induced vibration of a compliant conical structure, a series of model tests have been performed and some breakthrough progresses made. The ice sheet before the compliant conical structure is found to fail by two-time breaking in the tests. The process of two-time breaking behaves in two modes, and the general control of the ice and structural conditions determine the mode in which the ice force would behave. Two dynamic ice force functions are established respectively for the two modes of two-time breaking process in this paper. The numerical simulation results are in good agreement with the measured results, indicating that the dynamic ice force functions given in this paper can fully reflect the real situation of the dynamic ice force on a compliant conical structure. 展开更多
关键词 ice induced vibration compliant conical structure model test
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Three-dimensional distinct element modeling of fault reactivation and induced seismicity due to hydraulic fracturing injection and backflow 被引量:7
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作者 Zirui Yin Hongwei Huang +2 位作者 Fengshou Zhang Lianyang Zhang Shawn Maxwell 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第4期752-767,共16页
This paper presents a three-dimensional fully hydro-mechanical coupled distinct element study on fault reactivation and induced seismicity due to hydraulic fracturing injection and subsequent backflow process,based on... This paper presents a three-dimensional fully hydro-mechanical coupled distinct element study on fault reactivation and induced seismicity due to hydraulic fracturing injection and subsequent backflow process,based on the geological data in Horn River Basin,Northeast British Columbia,Canada.The modeling results indicate that the maximum magnitude of seismic events appears at the fracturing stage.The increment of fluid volume in the fault determines the cumulative moment and maximum fault slippage,both of which are essentially proportional to the fluid volume.After backflow starts,the fluid near the joint intersection keeps flowing into the critically stressed fault,rather than backflows to the wellbore.Although fault slippage is affected by the changes of both pore pressure and ambient rock stress,their contributions are different at fracturing and backflow stages.At fracturing stage,pore pressure change shows a dominant effect on induced fault slippage.While at backflow stage,because the fault plane is under a critical stress state,any minor disturbance would trigger a fault slippage.The energy analysis indicates that aseismic deformation takes up a majority of the total deformation energy during hydraulic fracturing.A common regularity is found in both fracturing-and backflow-induced seismicity that the cumulative moment and maximum fault slippage are nearly proportional to the injected fluid volume.This study shows some novel insights into interpreting fracturing-and backflowinduced seismicity,and provides useful information for controlling and mitigating seismic hazards due to hydraulic fracturing. 展开更多
关键词 induced seismicity Fault reactivation Hydraulic fracturing BACKFLOW Geomechanical modeling Distinct element method
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Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam 被引量:8
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作者 张小刚 宋玉普 吴智敏 《Transactions of Tianjin University》 EI CAS 2005年第1期59-65,共7页
By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture t... By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer′s optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice. 展开更多
关键词 roller-compacted concrete (RCC) arch dam induced crack double-K fracture parameters equivalent strength calculation model optimizing setting
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Hepatitis B virus infection modeling using multi-cellular organoids derived from human induced pluripotent stem cells 被引量:3
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作者 Di Cao Jian-Yun Ge +2 位作者 Yun Wang Tatsuya Oda Yun-Wen Zheng 《World Journal of Gastroenterology》 SCIE CAS 2021年第29期4784-4801,共18页
Chronic infection with hepatitis B virus(HBV)remains a global health concern despite the availability of vaccines.To date,the development of effective treatments has been severely hampered by the lack of reliable,repr... Chronic infection with hepatitis B virus(HBV)remains a global health concern despite the availability of vaccines.To date,the development of effective treatments has been severely hampered by the lack of reliable,reproducible,and scalable in vitro modeling systems that precisely recapitulate the virus life cycle and represent virus-host interactions.With the progressive understanding of liver organogenesis mechanisms,the development of human induced pluripotent stem cell(iPSC)-derived hepatic sources and stromal cellular compositions provides novel strategies for personalized modeling and treatment of liver disease.Further,advancements in three-dimensional culture of self-organized liver-like organoids considerably promote in vitro modeling of intact human liver tissue,in terms of both hepatic function and other physiological characteristics.Combined with our experiences in the investigation of HBV infections using liver organoids,we have summarized the advances in modeling reported thus far and discussed the limitations and ongoing challenges in the application of liver organoids,particularly those with multi-cellular components derived from human iPSCs.This review provides general guidelines for establishing clinical-grade iPSC-derived multi-cellular organoids in modeling personalized hepatitis virus infection and other liver diseases,as well as drug testing and transplantation therapy. 展开更多
关键词 Hepatitis B virus induced pluripotent stem cells Liver organoid Multicellular organoid modelING Transplantable
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Groundwater Flow Modeling by Using the Permeability Induced by Satellite Lineaments in Discontinuous Aquifers and Semi-Arid Context: A Case Study of the Liptako Region (South-West of Niger) 被引量:1
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作者 Saidou Garba Inaytoulaye Youssouf Koussoube +3 位作者 Abdel Kader Hassane Saley Issoufou Sandao Paul Hayes Boureima Ousmane 《Journal of Water Resource and Protection》 2019年第8期1090-1109,共20页
The study area, located in the Liptako basement of Niger, faces a serious problem of drinking water supply in recent decades. This is linked to exponential population growth and reduced rainfall. The purpose of this s... The study area, located in the Liptako basement of Niger, faces a serious problem of drinking water supply in recent decades. This is linked to exponential population growth and reduced rainfall. The purpose of this study is to map fracture networks from Landsat 7 satellite imagery to identify major subterranean flow corridors in the area. The methodological approach based on the collection of data (Landsat 7 images, DEM/SRTM, flow, transmissivity, static level) and the geological and hydrogeological field reconnaissance and the processing of these data with the following software (ArcGis, Envi, Surfer and RStudio) The results of this study yielded that the number of satellite lineaments is 995, the preferred directions of these satellite lineament are: N0°-10° (13%) and N90°-100° (12%). On the hydrographic network, in situ, the most frequent fracture, vein and dike directions are: N90°-100° (12%), N130°-150° (11%), and N50°-60° (10%). The structural domains identified probably correspond to the main corridors and reservoirs of underground flows. The values of the induced permeability are between 0.05 × 10-8 and 3.4 × 10-7 m/s. The permeability induced by satellite lineaments, which is strongly related to high fracturing densities and major water stream is involved in the hydrodynamic functioning of discontinuous aquifers in the study area. 展开更多
关键词 SATELLITE Image Circulation Corridor induced PERMEABILITY Hydrogeological modeling Tamou
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A Modified Monte Carlo Model of Speckle Tracking of Shear Wave Induced by Acoustic Radiation Force for Acousto-Optic Elasticity Imaging 被引量:3
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作者 李玉娇 黄伟骏 +3 位作者 马风超 王睿 陆明珠 万明习 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期54-57,共4页
A modified Monte Carlo model of speckle tracking of shear wave propagation in scattering media is proposed. The established Monte Carlo model mainly concerns the variations of optical electric field and speckle. The t... A modified Monte Carlo model of speckle tracking of shear wave propagation in scattering media is proposed. The established Monte Carlo model mainly concerns the variations of optical electric field and speckle. The two- dimensional intensity distribution and the time evolution of speckles in different probe locations are obtained. The fluctuation of speckle intensity tracks the acoustic-radiation-force shear wave propagation, and especially the reduction of speckle intensity implies attenuation of shear wave. Then, the shear wave velocity is estimated quantitatively on the basis of the time-to-peak algorithm and linear regression processing. The results reveal that a smaller sampling interval yields higher estimation precision and the shear wave velocity is estimated more efficiently by using speckle intensity difference than by using speckle contrast difference according to the estimation error. Hence, the shear wave velocity is estimated to be 2.25 m/s with relatively high accuracy for the estimation error reaches the minimum (0.071). 展开更多
关键词 of on IS for A Modified Monte Carlo model of Speckle Tracking of Shear Wave induced by Acoustic Radiation Force for Acousto-Optic Elasticity Imaging by in
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Establishing an experimental model of photodynamic induced anterior ischemic optic neuropathy 被引量:3
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作者 Runsheng Wang Xiaodi Wang +6 位作者 Peilin Lue Jianwei Bai Jianzhou Wang Xiaoqin Lei Xiao- liang Zhou Hongfen Sun Aizhu Pan 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第4期339-342,共4页
BACKGROUND: Scholars have supposed to establish animal models of optic neuropathy by pressing and partially amputating optic nerve, increasing intraocular pressure and injecting vasoconstrictor, etc., but the models ... BACKGROUND: Scholars have supposed to establish animal models of optic neuropathy by pressing and partially amputating optic nerve, increasing intraocular pressure and injecting vasoconstrictor, etc., but the models are greatly different from anterior ischemia optic neuropathy. Therefore, a more ideal method is needed to establish animal model of anterior ischemic optic neuropathy (AION). OBJECTIVE : To establish AION models in rats, observe the functional changes of fundus, fundus fluorescein angiography (FFA), optical coherence tomography (OCT), flash visual evoked potential (F-VEP), and histopathologically confirm its reliability. DESIGN: A randomized control tria SETTINGS : Department of Ophthalmology, Xi'an Fourth Hospital; Xi'an Institute of Ocular Fundus Diseases MATERIALS : The experiments were carried out in the research room of Xi'an Institute of Ocular Fundus Diseases from February 2005 to May 2006. Thirty healthy male SD rats of 4-5 weeks old, weighing 140-160 g, were provided by the animal experimental center of the Fourth Military Medical University of Chinese PLA [SCXK (Military)2002-005], and those without eye disease examined by slit lamp and direct ophthalmoscope after mydriasis were enrolled. The conditions for feeding mice without special pathogen were strictly followed. The rats were randomly divided into blank control group (n =5), laser group (n =5), hematoporphyrin derivative (HPD) group and AION group (n =15), each group was numbered randomly. For each rat, the right eye was taken as the experimental eye, and the left one as the control one. METHODS: In the AION group, the rats were injected with HPD (10 mg/kg) via caudal vein, and then the optic discs were exposed to krypton red (647 nm, 80 mV) for 120 s, and the rats were in avoidance of light for 2 weeks postoperatively. Rats in the laser group were only exposed to krypton red (647 rim, 80 mV) for 120 s, and in avoidance of light for 2 weeks postoperatively; Those in the HPD group were only injected with HPD (10 mg/kg) via caudal vein; Those in the blank control group were untouched. (1) Visual electrophysiological test: The F-VEP was used to evaluate the function of visual nerve. (2) FFA: After mydriasis and anesthesia as describe above, the fluorescein sodium parenteral solution (1 mL/kg) was injected v/a caudal vein and finished within about 3 s, the time of FFA was recorded from the beginning of injection, the video sight aimed at the optic disc and the surrounding area. (3) After mydriasis and anesthesia as describe above, the rats were examined with OCT. (4) Histological observation: After hematoxylin and eosin (HE) staining, the optic disc and surrounding blood vessels of retina were observed under light microscope at high power field. MAIN OUTCOME MEASURES: The results of fundus, FFA, visual electrophysiological test and OCT detection within 90 days after model establishment were observed. RESULTS: Of the 30 rats, 1 died after anesthesia in the laser group and 2 died in the AION group respectively, and finally 27 rats were involved in the analysis of results. (1) Changes in fundus: In the AION group, there was edema in upper optic disc and unclear boundary at 1 day after establishment, edema still could be observed at 6 days, and upper optic disc atrophied and appeared as pale at 90 days. (2) FFA results: In the AION group, early "low fluorescence", middle and late "high fluorescence" were observed in upper optic disc 1 day after model establishment, and there was "low fluorescence" at 6 days, and the low fluorescence could be observed all the time at 23 days. (3) Visual electrophysiological changes: In the AION group as compared with the control eyes, the experimental ones had prolonged F-VEP P100 latency [(71.65±8.81), (57.58±8.38) ms, t =3.148, P =0.012], and decreased wave amplitude [(4.77±1.90), (10.06±3.66) μV, t =4.082, P =0.003], and these changes lasted to 35 days after model establishment. (4) OCT results: In the AION group, the reflection surface of part nerve fiber layer was higher than the retina plane, the surface was rough and the thickness was increased at 6 days after model establishment. (5) Histopathological results: At 1 day after model establishment, part optic discs had highly edema, edema of nerve fibers, and loose tissue, also accompanied by the displacement of surrounding retina; At 23 days, the optic disc and surrounding nerve fiber layers became thinner, and the numbers of ganglion nuclei in the retina tissue sections were obviously decreased. These changes were not observed in the laser group, HPD group and blank control group. CONCLUSION : The changes of fundus, FFA, OCT, visual electrophysiology and histopathology confirmed that the krypton red laser irradiation (647 nm) at 2 hours after HPD was injected via caudal vein can establish more ideal animal models of AION. 展开更多
关键词 AION Establishing an experimental model of photodynamic induced anterior ischemic optic neuropathy
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An Induced Demand Model for High Speed 1 in UK 被引量:1
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作者 Francesca Pagliara John Preston 《Journal of Transportation Technologies》 2013年第1期44-51,共8页
Induced travel is an important component of travel demand and increasing attention has been paid to building analytical model to get more precise travel demand forecasting. In general, induced demand can be defined in... Induced travel is an important component of travel demand and increasing attention has been paid to building analytical model to get more precise travel demand forecasting. In general, induced demand can be defined in terms of additional trips that would be made if travel conditions improved (less congested, lower vehicle costs or tolls). In this paper the induced demand resulting from higher design speeds and, therefore by less travel time, for the High Speed 1 in UK will be modelled on the basis of the relationship between existing High Speed Rail demand (dependent variable) to existing High Speed Rail travel times and costs. The covariates include socioeconomic variables related to population and employment in the zones connected by the High Speed Rail services. This model has been calibrated by mean of a before and after study carried on the corridor, when the new High Speed Rail services was introduced. Elasticities of induced travel (trips and VMT) have been computed with respect to fares, travel time and service frequency. 展开更多
关键词 High SPEED RAIL induced DEMAND Regression models ELASTICITIES
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Ground State Meson Spectrum in a Relativistic Model with Instanton Induced Interaction 被引量:1
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作者 Antony Prakash Monteiro K.B.Vijaya Kumar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期325-330,共6页
The mass spectrum of the S-wave mesons is considered in the frame work of relativistic harmonic model (RHM). The full Hamiltonian used in the investigation has the Lorentz scalar plus a vector harmonic-oscillator po... The mass spectrum of the S-wave mesons is considered in the frame work of relativistic harmonic model (RHM). The full Hamiltonian used in the investigation has the Lorentz scalar plus a vector harmonic-oscillator potential, the confined-one-gluon-exchange potential (COGEP) and the instanton-induced quark-antiquak interaction (Ⅲ). A good description of the mass spectrum is obtained. The respective role of Ⅲ and COGEP in the S-wave meson spectrum is discussed. 展开更多
关键词 quark model confined-one-gluon-exchange potential instanton induced interaction S-wave spectra
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Mucosal-associated invariant T cells from induced pluripotent stem cells:A novel approach for modeling human diseases 被引量:2
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作者 Chie Sugimoto Hiroyoshi Fujita Hiroshi Wakao 《World Journal of Stem Cells》 SCIE CAS 2016年第4期158-169,共12页
Mice have frequently been used to model human diseases involving immune dysregulation such as autoimmune and inflammatory diseases.These models help elucidatethe mechanisms underlying the disease and in the developmen... Mice have frequently been used to model human diseases involving immune dysregulation such as autoimmune and inflammatory diseases.These models help elucidatethe mechanisms underlying the disease and in the development of novel therapies.However,if mice are deficient in certain cells and/or effectors associated with human diseases,how can their functions be investigated in this species?Mucosal-associated invariant T(MAIT)cells,a novel innate-like T cell family member,are a good example.MAIT cells are abundant in humans but scarce in laboratory mice.MAIT cells harbor an invariant T cell receptor and recognize nonpeptidic antigens vitamin B2metabolites from bacteria and yeasts.Recent studies have shown that MAIT cells play a pivotal role in human diseases such as bacterial infections and autoimmune and inflammatory diseases.MAIT cells possess granulysin,a human-specific effector molecule,but granulysin and its homologue are absent in mice.Furthermore,MAIT cells show poor proliferation in vitro.To overcome these problems and further our knowledge of MAIT cells,we have established a method to expand MAIT cells via induced pluripotent stem cells(iP SCs).In this review,we describe recent advances in the field of MAIT cell research and our approach for human disease modeling with iP SCderived MAIT cells. 展开更多
关键词 Mucosal-associated invariant T cells induced pluripotent stem cells DIFFERENTIATION Adoptive transfer Inflammatory diseases Autoimmune diseases Disease modeling Infectious diseases Immunocompromised mouse
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Induced pluripotent stem cells for modeling neurological disorders 被引量:4
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作者 Fabiele B Russo Fernanda R Cugola +2 位作者 Isabella R Fernandes Graciela C Pignatari Patricia C B Beltrão-Braga 《World Journal of Transplantation》 2015年第4期209-221,共13页
Several diseases have been successfully modeled since the development of induced pluripotent stem cell(i PSC) technology in 2006. Since then, methods for increased reprogramming efficiency and cell culture maintenance... Several diseases have been successfully modeled since the development of induced pluripotent stem cell(i PSC) technology in 2006. Since then, methods for increased reprogramming efficiency and cell culture maintenance have been optimized and many protocols for differentiating stem cell lines have been successfully developed, allowing the generation of several cellular subtypes in vitro. Gene editing technologies have also greatly advanced lately, enhancing disease-specific phenotypes by creating isogenic cell lines, allowing mutations to be corrected in affected samples or inserted in control lines. Neurological disorders have benefited the most from i PSC-disease modeling for its capability for generating disease-relevant cell types in vitro from the central nervous system, such as neurons and glial cells, otherwise only available from post-mortem samples. Patient-specific i PSC-derived neural cells can recapitulate the phenotypes of these diseases and therefore, considerably enrich our understanding of pathogenesis, disease mechanism and facilitate the development of drug screening platforms for novel therapeutic targets. Here, we review the accomplishments and the current progress in human neurological disorders by using i PSC modeling for Alzheimer's disease, Parkinson's disease, Huntington's disease, spinal muscular atrophy, amyotrophic lateral sclerosis, duchenne muscular dystrophy, schizophrenia and autism spectrum disorders, which include Timothy syndrome, Fragile X syndrome, Angelman syndrome, Prader-Willi syndrome, PhelanMc Dermid, Rett syndrome as well as Nonsyndromic Autism. 展开更多
关键词 Neurological disorders induced pluripotent stem cells Disease modeling Human neurons Drug screening
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Rabbit model of radiation-induced lung injury 被引量:2
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作者 Zhen-Zong Du Hua Ren +3 位作者 Jian-Fei Song Li-Fei Zhang Feng Lin Hai-Yong Wang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第3期237-241,共5页
Objective:To explore the feasibility of establishing an animal model of chronic radiationinduced lung injury.Methods:Twenty-eight New Zealand white rabbits were randomly divided into 3 groups(the right lung irradiatio... Objective:To explore the feasibility of establishing an animal model of chronic radiationinduced lung injury.Methods:Twenty-eight New Zealand white rabbits were randomly divided into 3 groups(the right lung irradiation group,the whole lung irradiation group and the control group).Animal model of radiation-induced lung injury was established b) highdoes radiotherapy in the irradiation groups,then all rabbits underwent CT and pathological examinations at 1.2.4.8.12.16 weeks,respectively after radiation.Results:Within 4 weeks of irradiation,some rabbits in the right lung irradiation group and whole lung irradiation group died. CT and pathological examinations all showed acute radiation pneumonitis.At 8-12 weeks after irradiation,CT scanning showed ground glass samples signs,patchy shadows and fibrotic stripes. Pathological examination showed the fibrosis pulmonary alveolar wall thickened obviously. Conclusions:The clinical animal model of chronic radiation-induced lung injury which corresponds to practical conditions in clinic can be successfully established. 展开更多
关键词 New Zealand RABBIT CHRONIC RADIATION-induced INJURY model
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Simplified Prediction Model for Vortex-Induced Vibrations of Top Tensioned Risers 被引量:4
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作者 薛鸿祥 唐文勇 张圣坤 《China Ocean Engineering》 SCIE EI 2008年第2期291-302,共12页
According to the characteristics of deepwater top tensioned risers, a simplified model is presented to predict the multi-modal response of vortex-induced vibration (VIV) in non-uniform flow based on energy equilibri... According to the characteristics of deepwater top tensioned risers, a simplified model is presented to predict the multi-modal response of vortex-induced vibration (VIV) in non-uniform flow based on energy equilibrium theory and the exporimental data from VIV self-excited and forced oscillations of rigid cylinders. The response amplitude of each mode is determined by a balance between the energy fed into the riser over the lock-in regions and the energy dissipated by the fluid damping over the remainders. Compared with the previous prediction models, this method can take fully account of the intrinsic nature of VIV for low mass ratio structures on lock-in regions, added mass and nonlinear fluid damping effect, etc. Moreover, it is the first time to propose the accurate calculating procedure for VIV amplitude correction factor by solving energy equilibrium equation and a closed form solution is presented for the case of a riser of uniform mass and cross-section oscillating in a uniform flow. The predicted values show a reasonable agreement with VIV experiments of riser models in stepped and sheared currents. 展开更多
关键词 top-tensioned riser vortex-induced vibration LOCK-IN simplified prediction model
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A Novel Wake Oscillator Model for Vortex-Induced Vibrations Prediction of A Cylinder Considering the Influence of Reynolds Number 被引量:2
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作者 GAO Xi-feng XIE Wu-de +2 位作者 XU Wan-hai BAI Yu-chuan ZHU Hai-tao 《China Ocean Engineering》 SCIE EI CSCD 2018年第2期132-143,共12页
It is well known that the Reynolds number has a significant effect on the vortex-induced vibrations(VIV) of cylinders. In this paper, a novel in-line(IL) and cross-flow(CF) coupling VIV prediction model for circular c... It is well known that the Reynolds number has a significant effect on the vortex-induced vibrations(VIV) of cylinders. In this paper, a novel in-line(IL) and cross-flow(CF) coupling VIV prediction model for circular cylinders has been proposed, in which the influence of the Reynolds number was comprehensively considered. The Strouhal number linked with the vortex shedding frequency was calculated through a function of the Reynolds number. The coefficient of the mean drag force was fitted as a new piecewise function of the Reynolds number, and its amplification resulted from the CF VIV was also taken into account. The oscillating drag and lift forces were modelled with classical van der Pol wake oscillators and their empirical parameters were determined based on the lock-in boundaries and the peak-amplitude formulas. A new peak-amplitude formula for the IL VIV was developed under the resonance condition with respect to the mass-damping ratio and the Reynolds number. When compared with the results from the experiments and some other prediction models, the present model could give good estimations on the vibration amplitudes and frequencies of the VIV both for elastically-mounted rigid and long flexible cylinders. The present model considering the influence of the Reynolds number could generally provide better results than that neglecting the effect of the Reynolds number. 展开更多
关键词 vortex-induced vibrations Reynolds number wake oscillator model CYLINDER
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Prediction Model for Vortex-Induced Vibration of Circular Cylinder with Data of Forced Vibration 被引量:3
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作者 潘志远 崔维成 刘应中 《China Ocean Engineering》 SCIE EI 2007年第2期239-254,共16页
A model based on the data from forced vibration experiments is developed for predicting the vortex-induced vibra- tions (VIV) of elastically mounted circular cylinders in flow. The assumptions for free and forced vi... A model based on the data from forced vibration experiments is developed for predicting the vortex-induced vibra- tions (VIV) of elastically mounted circular cylinders in flow. The assumptions for free and forced vibration tests are explored briefly. Energy equilibrium is taken into account to set up the relationship between the dynamic response of selfexcited oscillations and the force coemcients from forced vibration experiments. The gap between these two cases is bridged straightforwardly with careful treatment of key parameters. Given reduced mass m^# and material damping ratio of an elastically mounted circular cylinder in flow, the response characteristics such as amplitude, frequency, lock-in range, added mass coefficient, cross-flow fluid force and the corresponding phase angle can be predicted all at once. In- stances with different combination of reduced mass and material damping ratio are compared to investigate their effects on VIV. The hysteresis phenomenon can be interpreted reasonably. The predictions and the results from recent experiments carried out by Wifliamson' s group are in rather good agreement. 展开更多
关键词 vortex-induced vibration (VIV) forced oscillation experiments response prediction model
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Evaluation model of landslide hazards induced by the 2008 Wenchuan earthquake using strong motion data 被引量:3
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作者 Xiuying Wang Gaozhong Nie Mujun Ma 《Earthquake Science》 CSCD 2011年第3期311-319,共9页
Landslides induced by the 2008 Wenchuan earthquake in the Longmenshan area were relatively well instrumented, which makes it possible to investigate the landslides using ground motion records. Firstly, this paper anal... Landslides induced by the 2008 Wenchuan earthquake in the Longmenshan area were relatively well instrumented, which makes it possible to investigate the landslides using ground motion records. Firstly, this paper analyzes the data from Wenchuan earthquake on both regional and local site scale. The analyses show that the Newmark accumulative displacement calculated from the ground motion recorded in a particular geological hazard zone corresponds to the hazard intensity in that zone; the larger the displacement, the more serious the geologic hazard. The calculated result also shows that the displacement is related to the Arias intensity, which represents the total energy released during the earthquake at the observation site. Secondly, this paper constructs an evaluation model of Newmark displacement calculated with Arias intensities to estimate the subsequent slope failure resulting from the earthquake. The calculated results based on the model fit well with the distribution of actual landslides, suggesting that this method is useful for hazard evaluation. Therefore, this type of model can be used for estimating regional-scale distribution of earthquake-induced landslides and their associated hazards immediately after an earthquake. 展开更多
关键词 Wenchuan earthquake earthquake-induced landslide evaluation model Arias intensity earthquake intensity
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