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Drought Tolerance and Recovery of the Sedge Carex planostachys (Cyperaceae) from Central Texas Woodlands
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作者 E. Rob Wayne Oscar William Van Auken 《American Journal of Plant Sciences》 CAS 2024年第9期746-765,共20页
Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditio... Carex planostachys Kunze (Cyperaceae, Cedar sedge) is an herbaceous species in a genus commonly inhabiting mesic or hydric habitats. Carex planostachys is found in arid and semi-arid Juniperus woodlands. Arid conditions impose survival challenges to plants in dry areas. Some plants have plasticity responses to soil water content and continued normal though reduced functions through droughts, but most herbaceous plants do not survive. Limited previous studies have suggested C. planostachys is tolerant of drought. Physiological responses of C. planostachys from Juniperus woodlands was examined is this study to determine how long plants could survive without water and if they are capable of recovery from very negative water potentials beyond what is considered the permanent wilting point for most herbaceous plants. Plants were placed in pots in partial shade in this experiment. Water loss from the soil with plants was an inverse 2nd order polynomial function with soil water decreasing from 32% to 8% by day 28 of the study. Leaf water potential was also an inverse 2nd order polynomial function but did not decline significantly until 14 days without watering. Leaf water potential was −10.0 MPa after 35 days without watering. Non-watered plants Anet, (photosynthetic rate) was significantly lower compared to the water treatment by day 21 as was stomatal conductance and transpiration. When non-watered plants were watered after 21, 28 or 35 days, full recovery of physiological responses occurred within 7 days. The length of time that C. planostachys was able to withstand drought was greater than the annual trends in lack of precipitation during springtime in this area. Carex planostachys can photosynthesize at water stress between −8 and −10 MPa. Carex planostachys drought and shade tolerance enables it to occupy an understory niche devoid of other herbaceous plants. 展开更多
关键词 CO2 Uptake Conductance Gas Exchange Photosynthesis Respiration TRANSPIRATION Water Stress Water Potential.
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Seismic attribute and well-log analysis for channel characterization in the upper San Andres and Grayburg formations of the Midland Basin,Texas
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作者 Sumit Verma Esra Yalçın Yılmaz +3 位作者 Laura Ortiz Sanguino Justin Yandell Miles A.Henderson Robert C.Trentham 《Energy Geoscience》 EI 2024年第2期263-278,共16页
The Permian Basin is one of the most prolific,and currently one of the most active,oil and gas basins in the USA.The Lower Permian strata in the Permian Basin have produced more than 14 billion barrels of oil(BBO),mak... The Permian Basin is one of the most prolific,and currently one of the most active,oil and gas basins in the USA.The Lower Permian strata in the Permian Basin have produced more than 14 billion barrels of oil(BBO),making it the largest volume of hydrocarbon in the basin.Sedimentation in the Midland Basin during late Leonardian through early Guadalupian(ca.272-269 Ma)resulted in progradation of shelf edge and ultimately closure of the basin by Middle Permian time.We analyzed a merged seismic survey covering parts of the Permian Basin(i.e.,Central Basin Platform and Midland Basin)in Andrews,Ector,and Midland Counties,Texas.The seismic survey and well logs show the presence of gently dipping(ca.1°)clinoforms in the Upper San Andres and Grayburg Formations on the eastern edge of the Central Basin Platform and western Midland Basin.The seismic attributes,curvature,and spectral decomposition identify low sinuosity slope channels oriented north-south,but such channels do not appear beyond the slope.The shelf edge shifts from north to south during deposition of the Upper San Andres and Grayburg Formations.We identify five basinward shifts noted by the migration of the shelf edge toward the basin center and the presence of channel features along the depositional slope.The petrophysical analysis indicates that channels cut into carbonate rocks and are filled by siliciclastic sediments;this interpretation is supported by the most negative curvature anomalies along the channel axes caused by the differential compaction between the carbonate and siliciclastic rocks.There are a few channels with a northwest-southeast strike,which matches the direction of the Concho Lineament observed by satellite data.Such observations are consistent with previous interpretations of the northern Midland Basin closure during Middle-Late Permian time. 展开更多
关键词 PERMIAN SHELF CARBONATE
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Geologic characteristics,exploration and production progress of shale oil and gas in the United States:An overview
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作者 MCMAHON T P LARSON T E +1 位作者 ZHANG T SHUSTER M 《Petroleum Exploration and Development》 SCIE 2024年第4期925-948,共24页
We present a systematic summary of the geological characteristics,exploration and development history and current state of shale oil and gas in the United States.The hydrocarbon-rich shales in the major shale basins o... We present a systematic summary of the geological characteristics,exploration and development history and current state of shale oil and gas in the United States.The hydrocarbon-rich shales in the major shale basins of the United States are mainly developed in six geological periods:Middle Ordovician,Middle-Late Devonian,Early Carboniferous(Middle-Late Mississippi),Early Permian,Late Jurassic,and Late Cretaceous(Cenomanian-Turonian).Depositional environments for these shales include intra-cratonic basins,foreland basins,and passive continental margins.Paleozoic hydrocarbon-rich shales are mainly developed in six basins,including the Appalachian Basin(Utica and Marcellus shales),Anadarko Basin(Woodford Shale),Williston Basin(Bakken Shale),Arkoma Basin(Fayetteville Shale),Fort Worth Basin(Barnett Shale),and the Wolfcamp and Leonardian Spraberry/Bone Springs shale plays of the Permian Basin.The Mesozoic hydrocarbon-rich shales are mainly developed on the margins of the Gulf of Mexico Basin(Haynesville and Eagle Ford)or in various Rocky Mountain basins(Niobrara Formation,mainly in the Denver and Powder River basins).The detailed analysis of shale plays reveals that the shales are different in facies and mineral components,and"shale reservoirs"are often not shale at all.The United States is abundant in shale oil and gas,with the in-place resources exceeding 0.246×10^(12)t and 290×10^(12)m^(3),respectively.Before the emergence of horizontal well hydraulic fracturing technology to kick off the"shale revolution",the United States had experienced two decades of exploration and production practices,as well as theory and technology development.In 2007-2023,shale oil and gas production in the United States increased from approximately 11.2×10^(4)tons of oil equivalent per day(toe/d)to over 300.0×10^(4)toe/d.In 2017,the shale oil and gas production exceeded the conventional oil and gas production in the country.In 2023,the contribution from shale plays to the total U.S.oil and gas production remained above 60%.The development of shale oil and gas has largely been driven by improvements in drilling and completion technologies,with much of the recent effort focused on“cube development”or“co-development”.Other efforts to improve productivity and efficiency include refracturing,enhanced oil recovery,and drilling of“U-shaped”wells.Given the significant resources base and continued technological improvements,shale oil and gas production will continue to contribute significant volumes to total U.S.hydrocarbon production. 展开更多
关键词 United States shale oil shale gas shale reservoirs unconventional reservoirs oil and gas production resource assessment
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Research progress in friction stir processing of magnesium alloys and their metal matrix surface composites: Evolution in the 21^(st )century
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作者 Roshan Vijay Marode Tamiru Alemu Lemma +3 位作者 Nabihah Sallih Srinivasa Rao Pedapati Mokhtar Awang Adeel Hassan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2091-2146,共56页
Rising concerns about climate change drive the demand for lightweight components.Magnesium(Mg)alloys are highly valued for their low weight,making them increasingly important in various industries.Researchers focusing... Rising concerns about climate change drive the demand for lightweight components.Magnesium(Mg)alloys are highly valued for their low weight,making them increasingly important in various industries.Researchers focusing on enhancing the characteristics of Mg alloys and developing their Metal Matrix Composites(MMCs)have gained significant attention worldwide over the past decade,driven by the global shift towards lightweight materials.Friction Stir Processing(FSP)has emerged as a promising technique to enhance the properties of Mg alloys and produce Mg-MMCs.Initially,FSP adapted to refine grain size from the micro to the nano level and accelerated the development of MMCs due to its solid-state nature and the synergistic effects of microstructure refinement and reinforcement,improving strength,hardness,ductility,wear resistance,corrosion resistance,and fatigue strength.However,producing defect-free and sound FSPed Mg and Mg-MMCs requires addressing several variables and their interdependencies,which opens up a broad range of practical applications.Despite existing reviews on individual FSP of Mg,its alloys,and MMCs,an attempt has been made to analyze the latest research on these three aspects collectively to enhance the understanding,application,and effectiveness of FSP for Mg and its derivatives.This review article discusses the literature,classifies the importance of Mg alloys,provides a historical background,and explores developments and potential applications of FSPed Mg alloys.It focuses on novel fabrication methods,reinforcement strategies,machine and tool design parameters,material characterization,and integration with other methods for enhanced properties.The influence of process parameters and the emergence of defects are examined,along with specific applications in mono and hybrid composites and their microstructure evolution.The study identifies promising reinforcement materials and highlights research gaps in FSP for Mg alloys and MMCs production.It concludes with significant recommendations for further exploration,reflecting ongoing advancements in this field. 展开更多
关键词 Magnesium alloys Friction stir processing Metal matrix composites LIGHTWEIGHT Surface modification
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Data-driven diagnosis of high temperature PEM fuel cells based on the electrochemical impedance spectroscopy: Robustness improvement and evaluation
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作者 Dan Yu Xingjun Li +2 位作者 Samuel Simon Araya Simon Lennart Sahlin Vincenzo Liso 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期544-558,共15页
Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a cr... Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a critical and challenging task in real application. To enhance the robustness of diagnosis and achieve a more thorough evaluation of diagnostic performance, a robust diagnostic procedure based on electrochemical impedance spectroscopy (EIS) and a new method for evaluation of the diagnosis robustness was proposed and investigated in this work. To improve the diagnosis robustness: (1) the degradation mechanism of different faults in the high temperature PEM fuel cell was first analyzed via the distribution of relaxation time of EIS to determine the equivalent circuit model (ECM) with better interpretability, simplicity and accuracy;(2) the feature extraction was implemented on the identified parameters of the ECM and extra attention was paid to distinguishing between the long-term normal degradation and other faults;(3) a Siamese Network was adopted to get features with higher robustness in a new embedding. The diagnosis was conducted using 6 classic classification algorithms—support vector machine (SVM), K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), and Naive Bayes employing a dataset comprising a total of 1935 collected EIS. To evaluate the robustness of trained models: (1) different levels of errors were added to the features for performance evaluation;(2) a robustness coefficient (Roubust_C) was defined for a quantified and explicit evaluation of the diagnosis robustness. The diagnostic models employing the proposed feature extraction method can not only achieve the higher performance of around 100% but also higher robustness for diagnosis models. Despite the initial performance being similar, the KNN demonstrated a superior robustness after feature selection and re-embedding by triplet-loss method, which suggests the necessity of robustness evaluation for the machine learning models and the effectiveness of the defined robustness coefficient. This work hopes to give new insights to the robust diagnosis of high temperature PEM fuel cells and more comprehensive performance evaluation of the data-driven method for diagnostic application. 展开更多
关键词 PEM fuel cell Data-driven diagnosis Robustness improvement and evaluation Electrochemical impedance spectroscopy
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Role of peripheral amyloid-β aggregates in Alzheimer’s disease: mechanistic, diagnostic, and therapeutic implications
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作者 Nazaret Gamez Rodrigo Morales 《Neural Regeneration Research》 SCIE CAS 2025年第4期1087-1089,共3页
Compelling evidence demonstrates that the levels of peripheral amyloid-β(Aβ)fluctuate in Alzheimer’s disease(AD)patients.Moreover,Aβdeposits have been identified in peripheral tissues.However,the relevance of peri... Compelling evidence demonstrates that the levels of peripheral amyloid-β(Aβ)fluctuate in Alzheimer’s disease(AD)patients.Moreover,Aβdeposits have been identified in peripheral tissues.However,the relevance of peripheral Aβ(misfolded or not)in pathological situations,and the temporal appearance of these pathological fluctuations,are not well understood.The presence of misfolded Aβin peripheral compartments raises concerns on potential inter-individual transmissions considering the well-reported prion-like properties of this disease-associated protein.The latter is supported by multiple reports demonstrating that Aβmisfolding can be transmitted between humans and experimental animals through multiple routes of exposure.In this mini-review,we discuss the potential implications of peripheral,disease-associated Aβin disease mechanisms,as well as in diagnostic and therapeutic approaches. 展开更多
关键词 therapeutic AMYLOID latter
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Assessing the Performance of a Dynamical Downscaling Simulation Driven by a Bias-Corrected CMIP6 Dataset for Asian Climate
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作者 Zhongfeng XU Ying HAN +4 位作者 Meng-Zhuo ZHANG Chi-Yung TAM Zong-Liang YANG Ahmed M.EL KENAWY Congbin FU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期974-988,共15页
In this study,we aim to assess dynamical downscaling simulations by utilizing a novel bias-corrected global climate model(GCM)data to drive a regional climate model(RCM)over the Asia-western North Pacific region.Three... In this study,we aim to assess dynamical downscaling simulations by utilizing a novel bias-corrected global climate model(GCM)data to drive a regional climate model(RCM)over the Asia-western North Pacific region.Three simulations were conducted with a 25-km grid spacing for the period 1980–2014.The first simulation(WRF_ERA5)was driven by the European Centre for Medium-Range Weather Forecasts Reanalysis 5(ERA5)dataset and served as the validation dataset.The original GCM dataset(MPI-ESM1-2-HR model)was used to drive the second simulation(WRF_GCM),while the third simulation(WRF_GCMbc)was driven by the bias-corrected GCM dataset.The bias-corrected GCM data has an ERA5-based mean and interannual variance and long-term trends derived from the ensemble mean of 18 CMIP6 models.Results demonstrate that the WRF_GCMbc significantly reduced the root-mean-square errors(RMSEs)of the climatological mean of downscaled variables,including temperature,precipitation,snow,wind,relative humidity,and planetary boundary layer height by 50%–90%compared to the WRF_GCM.Similarly,the RMSEs of interannual-tointerdecadal variances of downscaled variables were reduced by 30%–60%.Furthermore,the WRF_GCMbc better captured the annual cycle of the monsoon circulation and intraseasonal and day-to-day variabilities.The leading empirical orthogonal function(EOF)shows a monopole precipitation mode in the WRF_GCM.In contrast,the WRF_GCMbc successfully reproduced the observed tri-pole mode of summer precipitation over eastern China.This improvement could be attributed to a better-simulated location of the western North Pacific subtropical high in the WRF_GCMbc after GCM bias correction. 展开更多
关键词 bias correction multi-model ensemble mean dynamical downscaling interannual variability day-to-day variability validation
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A New Definition of P-Value Involving the Maximum Likelihood Estimator
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作者 H. W. Corley 《Open Journal of Statistics》 2024年第5期546-552,共7页
We present here an alternative definition of the P-value for statistical hypothesis test of a real-valued parameter for a continuous random variable X. Our approach uses neither the notion of Type I error nor the assu... We present here an alternative definition of the P-value for statistical hypothesis test of a real-valued parameter for a continuous random variable X. Our approach uses neither the notion of Type I error nor the assumption that null hypothesis is true. Instead, the new P-value involves the maximum likelihood estimator, which is usually available for a parameter such as the mean μ or standard deviation σ of a random variable X with a common distribution. 展开更多
关键词 Hypothesis Testing P-VALUE EVIDENCE STATISTICS
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The ALMA-QUARKS Survey.Ⅱ.The ACA 1.3 mm Continuum Source Catalog and the Assembly of Dense Gas in Massive Star-Forming Clumps
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作者 许峰玮 Ke Wang +30 位作者 Tie Liu Lei Zhu Guido Garay Xunchuan Liu Paul Goldsmith Qizhou Zhang Patricio Sanhueza Shengli Qin Jinhua He Mika Juvela Anandmayee Tej Hongli Liu Shanghuo Li Kaho Morii Siju Zhang Jianwen Zhou Amelia Stutz Neal JEvans Kee-Tae Kim Shengyuan Liu Diego Mardones Guangxing Li Leonardo Bronfman Ken’ichi Tatematsu Chang Won Lee Xing Lu Xiaofeng Mai Sihan Jiao James O.Chibueze Keyun Su Viktor L.Tóth 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期119-139,共21页
Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation... Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data reduction.Combining multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star formation.The ACA 1.3 mm catalog includes 207 continuum sources that are called ACA sources.Their gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission model.The ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming protoclusters.We find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the two.When considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster formation.With the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary stage.We observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process. 展开更多
关键词 stars:formation ISM:kinematics and dynamics ISM:clouds stars:protostars
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Overexpression of mitogen-activated protein kinase phosphatase-1 in endothelial cells reduces blood-brain barrier injury in a mouse model of ischemic stroke 被引量:2
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作者 Xiu-De Qin Tai-Qin Yang +6 位作者 Jing-Hui Zeng Hao-Bin Cai Shao-Hua Qi Jian-Jun Jiang Ying Cheng Long-Sheng Xu Fan Bu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第8期1743-1749,共7页
Ischemic stroke can cause blood-brain barrier(BBB)injury,which worsens brain damage induced by stroke.Abnormal expression of tight junction proteins in endothelial cells(ECs)can increase intracellular space and BBB le... Ischemic stroke can cause blood-brain barrier(BBB)injury,which worsens brain damage induced by stroke.Abnormal expression of tight junction proteins in endothelial cells(ECs)can increase intracellular space and BBB leakage.Selective inhibition of mitogen-activated protein kinase,the negative regulatory substrate of mitogen-activated protein kinase phosphatase(MKP)-1,improves tight junction protein function in ECs,and genetic deletion of MKP-1 aggravates ischemic brain injury.However,whether the latter affects BBB integrity,and the cell type-specific mechanism underlying this process,remain unclear.In this study,we established an adult male mouse model of ischemic stroke by occluding the middle cerebral artery for 60 minutes and overexpressed MKP-1 in ECs on the injured side via lentiviral transfection before stroke.We found that overexpression of MKP-1 in ECs reduced infarct volume,reduced the level of inflammatory factors interleukin-1β,interleukin-6,and chemokine C-C motif ligand-2,inhibited vascular injury,and promoted the recovery of sensorimotor and memory/cognitive function.Overexpression of MKP-1 in ECs also inhibited the activation of cerebral ischemia-induced extracellular signal-regulated kinase(ERK)1/2 and the downregulation of occludin expression.Finally,to investigate the mechanism by which MKP-1 exerted these functions in ECs,we established an ischemic stroke model in vitro by depriving the primary endothelial cell of oxygen and glucose,and pharmacologically inhibited the activity of MKP-1 and ERK1/2.Our findings suggest that MKP-1 inhibition aggravates oxygen and glucose deprivation-induced cell death,cell monolayer leakage,and downregulation of occludin expression,and that inhibiting ERK1/2 can reverse these effects.In addition,co-inhibition of MKP-1 and ERK1/2 exhibited similar effects to inhibition of ERK1/2.These findings suggest that overexpression of MKP-1 in ECs can prevent ischemia-induced occludin downregulation and cell death via deactivating ERK1/2,thereby protecting the integrity of BBB,alleviating brain injury,and improving post-stroke prognosis. 展开更多
关键词 blood-brain barrier brain injury cerebral ischemia endothelial cells extracellular signal-regulated kinase 1/2 functional recovery mitogenactivated protein kinase phosphatase 1 OCCLUDIN oxygen and glucose deprivation transient middle cerebral artery occlusion
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A Comprehensive View on the Progress of Organoid Research with an Emphasis on its Relevance to Disease Characterization 被引量:1
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作者 Chandra KISHORE Vaishali Ji +7 位作者 Saurav Mallik Ayan MUKHERJI Namrata TOMAR Soumen Kumar Pati LI Ai Min Sinthia Roy BANERJEE Soumadip GHOSH Raza Ali NAQVI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第10期959-971,共13页
INTRODUCTION Organoids are primary tissue or stem cells derived cell aggregates that have the capacity for self-organization,self-renewal,and the capacity to mimic cellular and tissue level functions.Organoids can ove... INTRODUCTION Organoids are primary tissue or stem cells derived cell aggregates that have the capacity for self-organization,self-renewal,and the capacity to mimic cellular and tissue level functions.Organoids can overcome the shortcomings of traditional 2D cell culture models and closely mimic 3D primary tissue composition. 展开更多
关键词 functions. OVERCOME SHORTCOMINGS
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Management of pancreaticobiliary disease using a new intra-ductal endoscope:The Texas experience 被引量:23
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作者 Douglas S Fishman Paul R Tarnasky +1 位作者 Sandeep N Patel Isaac Raijman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第11期1353-1358,共6页
AIM:To evaluate a new single-operator mini-endoscope, Spyglass,for its performance,feasibility and safety in the management of pancreaticobiliary disease. METHODS:In a multicenter retrospective analysis of patients un... AIM:To evaluate a new single-operator mini-endoscope, Spyglass,for its performance,feasibility and safety in the management of pancreaticobiliary disease. METHODS:In a multicenter retrospective analysis of patients undergoing intraductal endoscopy,we evaluated 128 patients(71 men,mean age 57.6 years).Indications were therapeutic(TX)in 72(56%) and diagnostic(DX)in 56(44%). RESULTS:Peroral endoscopy was performed in 121 and percutaneous in seven.TX indications included CBD stones in 41,PD stones in six,and biliary strictures in 25.DX indications included abnormal LFT’s in 15, abnormal imaging in 38 and cholangiocarcinoma staging in three.Visualization of the stone(s)was considered good in 31,fair in six,and poor in four. Advancement of the electrohydraulic lithotripsy probe was not possible in three patients and proper targeting of the lesion was partial in four patients.A holmium laser was used successfully in three patients.Ductal clearance was achieved in 37 patients after one procedure and in four patients after two procedures.Diagnosis of biliary strictures was modified in 20/29 and confirmed to be malignant in 10/23.Of the modified patients,no diagnosis was available in 17.Spyglass demonstrated malignancy in 8/17 and non-malignancy in nine.Suspected pathology by imaging studies and abnormal LFT’s was modified in 43/63(66%).Staging of cholangiocarcinoma demonstrated multicentric cholangiocarcinoma in 2/3.There was no morbidity associated with the use of Spyglass. CONCLUSION:Spyglass Spyscopeis a first generation, single operator miniature endoscope that can evaluate and treat various biliary and pancreatic tract diseases. 展开更多
关键词 Intra-ductal endoscopy CHOLEDOCHOSCOPY Cholangiopancreatoscopy Endoscopic retrogradecholangiopancreatography Biliary disease Sclerosingcholangitis CHOLANGIOCARCINOMA LITHOTRIPSY Pancreaticdisease Spyglass
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Towards a unified nonlocal, peridynamics framework for the coarse-graining of molecular dynamics data with fractures
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作者 H.Q.YOU X.XU +3 位作者 Y.YU S.SILLING M.D'ELIA J.FOSTER 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第7期1125-1150,共26页
Molecular dynamics(MD)has served as a powerful tool for designing materials with reduced reliance on laboratory testing.However,the use of MD directly to treat the deformation and failure of materials at the mesoscale... Molecular dynamics(MD)has served as a powerful tool for designing materials with reduced reliance on laboratory testing.However,the use of MD directly to treat the deformation and failure of materials at the mesoscale is still largely beyond reach.In this work,we propose a learning framework to extract a peridynamics model as a mesoscale continuum surrogate from MD simulated material fracture data sets.Firstly,we develop a novel coarse-graining method,to automatically handle the material fracture and its corresponding discontinuities in the MD displacement data sets.Inspired by the weighted essentially non-oscillatory(WENO)scheme,the key idea lies at an adaptive procedure to automatically choose the locally smoothest stencil,then reconstruct the coarse-grained material displacement field as the piecewise smooth solutions containing discontinuities.Then,based on the coarse-grained MD data,a two-phase optimizationbased learning approach is proposed to infer the optimal peridynamics model with damage criterion.In the first phase,we identify the optimal nonlocal kernel function from the data sets without material damage to capture the material stiffness properties.Then,in the second phase,the material damage criterion is learnt as a smoothed step function from the data with fractures.As a result,a peridynamics surrogate is obtained.As a continuum model,our peridynamics surrogate model can be employed in further prediction tasks with different grid resolutions from training,and hence allows for substantial reductions in computational cost compared with MD.We illustrate the efficacy of the proposed approach with several numerical tests for the dynamic crack propagation problem in a single-layer graphene.Our tests show that the proposed data-driven model is robust and generalizable,in the sense that it is capable of modeling the initialization and growth of fractures under discretization and loading settings that are different from the ones used during training. 展开更多
关键词 nonlocal model machine learning HOMOGENIZATION PERIDYNAMICS material fracture
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Functional phenotyping of microglia highlights the dark relationship between chronic traumatic brain injury and normal age-related pathology
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作者 Rodney M.Ritzel Junfang Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第4期811-813,共3页
Traumatic brain injury(TBI) is a major cause of death and disability worldwide. Age-related TBI differences demonstrate the third peak of prevalence and incidence of TBI within the elderly population. This is due to t... Traumatic brain injury(TBI) is a major cause of death and disability worldwide. Age-related TBI differences demonstrate the third peak of prevalence and incidence of TBI within the elderly population. This is due to the elderly being at a higher risk of sustaining falls, which have been identified as the main cause(40–50%) of TBI. 展开更多
关键词 TBI death injury
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Facile synthesis of chromium chloride/poly(methyl methacrylate) core/shell nanocapsules by inverse miniemulsion evaporation method and application as delayed crosslinker in secondary oil recovery
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作者 Jing-Yang Pu Keith P.Johnston +4 位作者 Ping-Keng Wu Muaaz Ahmad Ming-Liang Luo Na Zhang Ju-Tao He 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期396-406,共11页
Cr(III)ehydrolyzed polyacrylamide(HPAM)gels have been extensively studied as a promising strategy controlling waste water production for mature oilfields.However,the gelation time of the current technologies is not lo... Cr(III)ehydrolyzed polyacrylamide(HPAM)gels have been extensively studied as a promising strategy controlling waste water production for mature oilfields.However,the gelation time of the current technologies is not long enough for in-depth placement.In this study,we report a novel synthesis method to obtain chromium chloride/poly(methyl methacrylate)(PMMA)nanocapsules which can significantly delay the gelation of HPAM through encapsulating the chromium chloride crosslinker.The chromium chloride-loaded nanocapsules(CreNC)are prepared via a facile inverse miniemulsion evaporation method during which the hydrophobic PMMA polymers,pre-dispersed in an organic solvent,were carefully controlled to precipitate onto stable aqueous miniemulsion droplets.The stable aqueous nanodroplets(W)containing Cr(III)are dispersed in a mixture of organic solvent(O1)with PMMA and nonsolvent medium(O2)to prepare an inverse miniemulsion.With the evaporation of the O1,PMMA forms CreNCs around the aqueous droplets.The CreNCs are readily transferred into water from the organic nonsolvent phase.The CreNCs exhibit the tunable size(358-983 nm),Cr loading(7.1%-19.1%),and Cr entrapment efficiency(11.7%-80.2%),with tunable zeta potentials in different PVA solutions.The CreNCs can delay release of Cr(III)and prolong the gelation time of HPAM up to 27 days. 展开更多
关键词 NANOCAPSULES Inverse miniemulsion evaporation Chromium chloride crosslinker HPAM gelation Secondary oil recovery
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Collagen matrix scaffolds:Future perspectives for the management of chronic liver diseases
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作者 Moises Martinez-Castillo Itzel Altamirano-Mendoza +3 位作者 Rafal Zielinski Waldemar Priebe Cristina Piña-Barba Gabriela Gutierrez-Reyes 《World Journal of Clinical Cases》 SCIE 2023年第6期1224-1235,共12页
Approximately 1.5 billion chronic liver disease(CLD)cases have been estimated worldwide,encompassing a wide range of liver damage severities.Moreover,liver disease causes approximately 1.75 million deaths per year.CLD... Approximately 1.5 billion chronic liver disease(CLD)cases have been estimated worldwide,encompassing a wide range of liver damage severities.Moreover,liver disease causes approximately 1.75 million deaths per year.CLD is typically characterized by the silent and progressive deterioration of liver parenchyma due to an incessant inflammatory process,cell death,over deposition of extracellular matrix proteins,and dysregulated regeneration.Overall,these processes impair the correct function of this vital organ.Cirrhosis and liver cancer are the main complications of CLD,which accounts for 3.5%of all deaths worldwide.Liver transplantation is the optimal therapeutic option for advanced liver damage.The liver is one of the most common organs transplanted;however,only 10%of liver transplants are successful.In this context,regenerative medicine has made significant progress in the design of biomaterials,such as collagen matrix scaffolds,to address the limitations of organ transplantation(e.g.,low donation rates and biocompatibility).Thus,it remains crucial to continue with experimental and clinical studies to validate the use of collagen matrix scaffolds in liver disease. 展开更多
关键词 LIVER Chronic liver disease Collagen matrix scaffold TRANSPLANT MANAGEMENT
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Adsorption of methane onto mudstones under supercritical conditions: Mechanisms, physical properties and thermodynamic parameters
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作者 Yang Wang Hong-Fei Cheng +4 位作者 Qin-Hong Hu Lang-Bo Jia Xi-Meng Wang Sha-Sha Gao Luo-Fu Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期34-47,共14页
Since the mechanisms of methane-mudstone interactions are important for estimating shale gas reserves,methane adsorption under supercritical conditions of 30 MPa pressure and 303.15,333.15,363.15 K temperatures was st... Since the mechanisms of methane-mudstone interactions are important for estimating shale gas reserves,methane adsorption under supercritical conditions of 30 MPa pressure and 303.15,333.15,363.15 K temperatures was studied to measure the excess methane adsorption in two mudstone samples from Yanchang Formation,Ordos Basin.Excess adsorption features inflection points where the amount of adsorbed gas changes from increasing to decreasing concentrations.Three methods(fixed,slope,and freely fitted density)were applied to calculate the adsorbed-phase density(rad),which was then used to fit the measured excess adsorption.Two criteria,the goodness-of-fit and whether the fitting can obtain reasonable absolute adsorption,were applied to determine the most accurate model.Results indicated that the supercritical Dubinin-Radushkevich(SDR)model with freely fitted rad was the most reasonable model.The volume of adsorbed methane at 363.15 K is close to the micropore(d<2 nm)volume of the corresponding mudstone.Considering the actual geological conditions,the adsorbed gas should be predominantly stored in micropores.Thermodynamic parameters reveal that the methane adsorption on mudstone is a physisorption process that is jointly controlled by the heterogeneity of,and interaction forces between the methane molecule and,the rock surface. 展开更多
关键词 Supercritical methane adsorption Excess adsorption Adsorbed-phase density Adsorption model Thermodynamic feature
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Concentrated ternary ether electrolyte allows for stable cycling of a lithium metal battery with commercial mass loading high-nickel NMC and thin anodes
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作者 Jun Yang Xing Li +17 位作者 Ke Qu Yixian Wang Kangqi Shen Changhuan Jiang Bo Yu Pan Luo Zhuangzhi Li Mingyang Chen Bingshu Guo Mingshan Wang Junchen Chen Zhiyuan Ma Yun Huang Zhenzhong Yang Pengcheng Liu Rong Huang Xiaodi Ren David Mitlin 《Carbon Energy》 SCIE CSCD 2023年第3期2-18,共17页
A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes ... A new concentrated ternary salt ether-based electrolyte enables stable cycling of lithium metal battery(LMB)cells with high-mass-loading(13.8 mg cm^(−2),2.5 mAh cm^(−2))NMC622(LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2))cathodes and 50μm Li anodes.Termed“CETHER-3,”this electrolyte is based on LiTFSI,LiDFOB,and LiBF4 with 5 vol%fluorinated ethylene carbonate in 1,2-dimethoxyethane.Commer-cial carbonate and state-of-the-art binary salt ether electrolytes were also tested as baselines.With CETHER-3,the electrochemical performance of the full-cell battery is among the most favorably reported in terms of high-voltage cycling stability.For example,LiNi_(x)Mn_(y)Co_(1-x-y)O_(2)(NMC)-Li metal cells retain 80%capacity at 430 cycles with a 4.4 V cut-off and 83%capacity at 100 cycles with a 4.5 V cut-off(charge at C/5,discharge at C/2).According to simulation by density functional theory and molecular dynamics,this favorable performance is an outcome of enhanced coordination between Li^(+)and the solvent/salt molecules.Combining advanced microscopy(high-resolution transmission electron microscopy,scanning electron microscopy)and surface science(X-ray photoelectron spectroscopy,time-of-fight secondary ion mass spectroscopy,Fourier-transform infrared spectroscopy,Raman spectroscopy),it is demonstrated that a thinner and more stable cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)are formed.The CEI is rich in lithium sulfide(Li_(2)SO_(3)),while the SEI is rich in Li_(3)N and LiF.During cycling,the CEI/SEI suppresses both the deleterious transformation of the cathode R-3m layered near-surface structure into disordered rock salt and the growth of lithium metal dendrites. 展开更多
关键词 concentrated electrolyte density functional theory ether electrolyte high‐nickel cathode high‐voltage battery molecular dynamics
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An Uneven Impact of Emerging Technologies on Taxpayers With Various Income Levels Audited by the IRS: Empirical Evidence From an AI Technology Application and Regression Models
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作者 Gordon Leeroy 《Journal of Modern Accounting and Auditing》 2023年第4期83-92,共10页
This study aims to investigate the influence of emerging technology adoption on tax compliance, encompassing both the Internal Revenue Service’s (IRS) compliance audits and taxpayers’ compliance performance (collect... This study aims to investigate the influence of emerging technology adoption on tax compliance, encompassing both the Internal Revenue Service’s (IRS) compliance audits and taxpayers’ compliance performance (collectively, tax compliance). We employed the Gradient Descent optimization algorithm, an artificial intelligence (AI) technology application, to scrutinize the connection between the quality of US tax filings and the development of emerging technology, among other contributing factors. Additionally, we utilized multiple linear regression to evaluate the relationships between dependent variables, specifically IRS audit rates and the no-change rate at different income levels,1 and several independent variables, including a proxy for emerging technology in the form of tax software. Our findings reveal that while emerging technology significantly impacts tax compliance within the IRS and taxpayers’ performance, its effects vary across income groups. Notably, emerging technology seems to confer greater advantages to higher-income individuals compared to their lower-income counterparts. These study results hold considerable policy implications for government decision-makers in promoting the adoption of emerging technology among lower-income taxpayers. 展开更多
关键词 IRS Audit taxpayer compliance emerging technology artificial intelligence tax software income levels
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A unified fractional flow framework for predicting the liquid holdup in two-phase pipe flows
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作者 Fuqiao Bai Yingda Lu Mukul M.Sharma 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2614-2624,共11页
Two-phase pipe flow occurs frequently in oil&gas industry,nuclear power plants,and CCUS.Reliable calculations of gas void fraction(or liquid holdup)play a central role in two-phase pipe flow models.In this paper w... Two-phase pipe flow occurs frequently in oil&gas industry,nuclear power plants,and CCUS.Reliable calculations of gas void fraction(or liquid holdup)play a central role in two-phase pipe flow models.In this paper we apply the fractional flow theory to multiphase flow in pipes and present a unified modeling framework for predicting the fluid phase volume fractions over a broad range of pipe flow conditions.Compared to existing methods and correlations,this new framework provides a simple,approximate,and efficient way to estimate the phase volume fraction in two-phase pipe flow without invoking flow patterns.Notably,existing correlations for estimating phase volume fraction can be transformed and expressed under this modeling framework.Different fractional flow models are applicable to different flow conditions,and they demonstrate good agreement against experimental data within 5%errors when compared with an experimental database comprising of 2754 data groups from 14literature sources,covering various pipe geometries,flow patterns,fluid properties and flow inclinations.The gas void fraction predicted by the framework developed in this work can be used as inputs to reliably model the hydraulic and thermal behaviors of two-phase pipe flows. 展开更多
关键词 Pipe fractional flow Liquid holdup Multiphase pipe flow Gas void fraction
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