For more than a half century, my colleagues and I in the Stony Brook High Pressure Laboratory have profited from collaborations with French scientists in their laboratories in Orsay, Paris, Toulouse, Lille, Lyon, Stra...For more than a half century, my colleagues and I in the Stony Brook High Pressure Laboratory have profited from collaborations with French scientists in their laboratories in Orsay, Paris, Toulouse, Lille, Lyon, Strasbourg and </span><span style="font-family:Verdana;">Rennes. These interactions have included postdoctoral appointments of French colleagues in our laboratory as well as two année sabbatique by me;in 1983-84</span><span style="font-family:Verdana;">, in the Laboratoire de Géophysique et Géodynamique Interne at the Université Paris XI in Orsay and in 2020-2003 in the Laboratoire des Méchanismes et Transfert en Géologie at the Université Paul Sabatier in Toulouse. The objective of this report is to relate this history and to illustrate the scientific advances which </span></span><span style="font-family:Verdana;">resulted</span><span style="font-family:Verdana;"> from these collaborations.展开更多
For the past half-century, I have been fortunate in maintaining collaborations with Czech scientists in the Czech Republic [formerly Czechoslovakia] from the Geofyzikální ústav-GFU [Institute of Geophys...For the past half-century, I have been fortunate in maintaining collaborations with Czech scientists in the Czech Republic [formerly Czechoslovakia] from the Geofyzikální ústav-GFU [Institute of Geophysics] of the <span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">eskoslovenská Akademie Věd-</span><span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">SAV [Czechoslovak Academy of Sciences]. These collaborations have included exchange visits by me to Prague [Praha] and convening international workshops in 1976, 1986 and 1996 in castles used by the </span><span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">SAV as well as visits by Czech colleagues to Stony Brook University. The objective of this report is to relate this history. This paper is dedicated to the memory of Vladislav Babu</span><span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">ka.</span>展开更多
The power grid is undergoing a transformation from synchronous generators(SGs) toward inverter-based resources(IBRs). The stochasticity, asynchronicity, and limited-inertia characteristics of IBRs bring about challeng...The power grid is undergoing a transformation from synchronous generators(SGs) toward inverter-based resources(IBRs). The stochasticity, asynchronicity, and limited-inertia characteristics of IBRs bring about challenges to grid resilience. Virtual power plants(VPPs) are emerging technologies to improve the grid resilience and advance the transformation. By judiciously aggregating geographically distributed energy resources(DERs) as individual electrical entities, VPPs can provide capacity and ancillary services to grid operations and participate in electricity wholesale markets. This paper aims to provide a concise overview of the concept and development of VPPs and the latest progresses in VPP operation, with the focus on VPP scheduling and control. Based on this overview, we identify a few potential challenges in VPP operation and discuss the opportunities of integrating the multi-agent system(MAS)-based strategy into the VPP operation to enhance its scalability, performance and resilience.展开更多
The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental change.It is extremely important to...The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental change.It is extremely important to investigate the interactions among atmospheric CO_(2),the physical climate system,and the carbon cycle of the underlying surface for a better understanding of the Earth system.Earth system models are widely used to investigate these interactions via coupled carbon-climate simulations.The Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0)has successfully fixed a two-way coupling of atmospheric CO_(2)with the climate and carbon cycle on land and in the ocean.Using CAS-ESM2.0,we conducted a coupled carbon-climate simulation by following the CMIP6 proposal of a historical emissions-driven experiment.This paper examines the modeled CO_(2)by comparison with observed CO_(2)at the sites of Mauna Loa and Barrow,and the Greenhouse Gases Observing Satellite(GOSAT)CO_(2)product.The results showed that CAS-ESM2.0 agrees very well with observations in reproducing the increasing trend of annual CO_(2)during the period 1850-2014,and in capturing the seasonal cycle of CO_(2)at the two baseline sites,as well as over northern high latitudes.These agreements illustrate a good ability of CAS-ESM2.0 in simulating carbon-climate interactions,even though uncertainties remain in the processes involved.This paper reports an important stage of the development of CAS-ESM with the coupling of carbon and climate,which will provide significant scientific support for climate research and China’s goal of carbon neutrality.展开更多
Within the last few decades, increases in computational resources have contributed enormously to the progress of science and engineering (S & E). To continue making rapid advancements, the S & E community must...Within the last few decades, increases in computational resources have contributed enormously to the progress of science and engineering (S & E). To continue making rapid advancements, the S & E community must be able to access computing resources. One way to provide such resources is through High-Performance Computing (HPC) centers. Many academic research institutions offer their own HPC Centers but struggle to make the computing resources easily accessible and user-friendly. Here we present SHABU, a RESTful Web API framework that enables S & E communities to access resources from Boston University’s Shared Computing Center (SCC). The SHABU requirements are derived from the use cases described in this work.展开更多
BACKGROUND Irritable bowel syndrome(IBS)is the most prevalent gastrointestinal disorder in developed countries and reduces patients’quality of life,hinders their ability to work,and increases health care costs.A grow...BACKGROUND Irritable bowel syndrome(IBS)is the most prevalent gastrointestinal disorder in developed countries and reduces patients’quality of life,hinders their ability to work,and increases health care costs.A growing number of trials have demonstrated an aberrant gut microbiota composition in IBS,also known as‘gut dysbiosis’.Fecal microbiota transplantation(FMT)has been suggested as a treatment for IBS.AIM To assess the efficacy and safety of FMT for the treatment of IBS.METHODS We searched Cochrane Central,MEDLINE,EMBASE and Web of Science up to 24 October 2022 for randomised controlled trials(RCTs)investigating the effectiveness of FMT compared to placebo(including autologous FMT)in treating IBS.The primary outcome was the number of patients with improvements of symptoms measured using a validated,global IBS symptoms score.Secondary outcomes were changes in quality-of-life scores,non-serious and serious adverse events.Risk ratios(RR)and corresponding 95%CI were calculated for dichotomous outcomes,as were the mean differences(MD)and 95%CI for continuous outcomes.The Cochrane risk of bias tool was used to assess the quality of the trials.GRADE criteria were used to assess the overall quality of the evidence.RESULTS Eight RCTs(484 participants)were included in the review.FMT resulted in no significant benefit in IBS symptoms three months after treatment compared to placebo(RR 1.19,95%CI:0.68-2.10).Adverse events were reported in 97 participants in the FMT group and in 45 participants in the placebo group(RR 1.17,95%CI:0.63-2.15).One serious adverse event occurred in the FMT group and two in the placebo group(RR 0.42,95%CI:0.07-2.60).Endoscopic FMT delivery resulted in a significant improvement in symptoms,while capsules did not.FMT did not improve the quality of life of IBS patients but,instead,appeared to reduce it,albeit non significantly(MD-6.30,95%CI:-13.39-0.79).The overall quality of the evidence was low due to moderate-high inconsistency,the small number of patients in the studies,and imprecision.CONCLUSION We found insufficient evidence to support or refute the use of FMT for IBS.Larger trials are needed.展开更多
Mechanical metamaterials such as auxetic materials have attracted great interest due to their unusual properties that are dictated by their architectures.However,these architected materials usually have low stiffness ...Mechanical metamaterials such as auxetic materials have attracted great interest due to their unusual properties that are dictated by their architectures.However,these architected materials usually have low stiffness because of the bending or rotation deformation mechanisms in the microstructures.In this work,a convolutional neural network(CNN)based self-learning multi-objective optimization is performed to design digital composite materials.The CNN models have undergone rigorous training using randomly generated two-phase digital composite materials,along with their corresponding Poisson's ratios and stiffness values.Then the CNN models are used for designing composite material structures with the minimum Poisson's ratio at a given volume fraction constraint.Furthermore,we have designed composite materials with optimized stiffness while exhibiting a desired Poisson's ratio(negative,zero,or positive).The optimized designs have been successfully and efficiently obtained,and their validity has been confirmed through finite element analysis results.This self-learning multi-objective optimization model offers a promising approach for achieving comprehensive multi-objective optimization.展开更多
This study proposes a cost-effective machine-learning based model for predicting velocity and turbulence kineticenergy fields in the wake of wind turbines for yaw control applications.The model consists of an auto-enc...This study proposes a cost-effective machine-learning based model for predicting velocity and turbulence kineticenergy fields in the wake of wind turbines for yaw control applications.The model consists of an auto-encoderconvolutional neural network(ACNN)trained to extract the features of turbine wakes using instantaneous datafrom large-eddy simulation(LES).The proposed framework is demonstrated by applying it to the Sandia NationalLaboratory Scaled Wind Farm Technology facility consisting of three 225 kW turbines.LES of this site is performedfor different wind speeds and yaw angles to generate datasets for training and validating the proposed ACNN.It is shown that the ACNN accurately predicts turbine wake characteristics for cases with turbine yaw angleand wind speed that were not part of the training process.Specifically,the ACNN is shown to reproduce thewake redirection of the upstream turbine and the secondary wake steering of the downstream turbine accurately.Compared to the brute-force LES,the ACNN developed herein is shown to reduce the overall computational costrequired to obtain the steady state first and second-order statistics of the wind farm by about 85%.展开更多
Valuable information on dynamics of expanding fluids can be inferred from the response of such systems to perturbations in their initial geometry.We apply this technique in high-energy^(96)Ru+^(96)Ru and^(96)Zr+^(96)Z...Valuable information on dynamics of expanding fluids can be inferred from the response of such systems to perturbations in their initial geometry.We apply this technique in high-energy^(96)Ru+^(96)Ru and^(96)Zr+^(96)Zr collisions to scrutinize the expansion dynamics of the quark-gluon plasma,where the initial geometry perturbations are sourced by the differences in deformations and radial profiles between^(96)Ru and^(96)Zr,and the collective response is captured by the change in anisotropic flow Vn between the two collision systems.Using a transport model,we analyze how the nonlinear coupling between lower-order flow harmonics V_(2)and V_(3)to the higher-order flow harmonics V_(4)and V_(5),expected to scale as V_(4)NL= χ_(4)V_(2)2and V_(5)NL= χ_(5)V_(2)V_(3),gets modified as one moves from^(96)Ru+^(96)Ru to^(96)Zr+^(96)Zr systems.We find that these scaling relations are valid to high precision:variations of order 20% in V_(4)NLand V_(5)NLdue to differences in quadrupole deformation,octupole deformation,and nuclear skin modify χ_(4)and χ_(5)by about 1–2%.Percent-level deviations are however larger than the expected experimental uncertainties and could be measured.Therefore,collisions of isobars with different nuclear structures are a unique tool to isolate subtle nonlinear effects in the expansion of the quark-gluon plasma that would be otherwise impossible to access in a single collision system.展开更多
Few previous Reversible Visible Watermarking(RVW)schemes have both good transparency and watermark visibility.An adaptive RVW scheme that integrates Total Variation and visual perception in Block Truncation Coding(BTC...Few previous Reversible Visible Watermarking(RVW)schemes have both good transparency and watermark visibility.An adaptive RVW scheme that integrates Total Variation and visual perception in Block Truncation Coding(BTC)compressed domain,called TVB-RVW is proposed in this paper.A new mean image estimation method for BTC-compressed images is first developed with the help of Total Variation.Then,a visual perception factor computation model is devised by fusing texture and luminance characteristics.An adaptive watermark embedding strategy is used to embed the visible watermark with the effect of the visual perception factor in the BTC domain.Moreover,a lossless embedding method of the encrypted visible watermark is exploited to deter illegal watermark removal.The visible watermark can be removed since the visual perception factor and the estimated mean image remain unchanged before and after watermark embedding.Extensive experiments validate the superiority of the proposed algorithm over previous RVW schemes in BTC in terms of the visual quality of watermarked images and watermark visibility,and it can achieve a good balance between transparency and watermark visibility.展开更多
Background In this work,we focus on the label layout problem:specifying the positions of overlaid virtual annotations in Virtual/Augmented Reality scenarios.Methods Designing a layout of labels that does not violate d...Background In this work,we focus on the label layout problem:specifying the positions of overlaid virtual annotations in Virtual/Augmented Reality scenarios.Methods Designing a layout of labels that does not violate domain-specific design requirements,while at the same time satisfying aesthetic and functional principles of good design,can be a daunting task even for skilled visual designers.Presenting the annotations in 3D object space instead of projection space,allows for the preservation of spatial and depth cues.This results in stable layouts in dynamic environments,since the annotations are anchored in 3D space.Results In this paper we make two major contributions.First,we propose a technique for managing the layout and rendering of annotations in Virtual/Augmented Reality scenarios by manipulating the annotations directly in 3D space.For this,we make use of Artificial Potential Fields and use 3D geometric constraints to adapt them in 3D space.Second,we introduce PartLabeling:an open source platform in the form of a web application that acts as a much-needed generic framework allowing to easily add labeling algorithms and 3D models.This serves as a catalyst for researchers in this field to make their algorithms and implementations publicly available,as well as ensure research reproducibility.The PartLabeling framework relies on a dataset that we generate as a subset of the original PartNet dataset consisting of models suitable for the label management task.The dataset consists of 10003D models with part annotations.展开更多
BACKGROUND Ewing sarcoma(ES)is a malignant neoplasm of neuroectodermal origin and is commonly observed in children and young adults.The musculoskeletal system is the main body system impacted and ES is rarely seen in ...BACKGROUND Ewing sarcoma(ES)is a malignant neoplasm of neuroectodermal origin and is commonly observed in children and young adults.The musculoskeletal system is the main body system impacted and ES is rarely seen in the visceral organs particularly the adrenal gland.AIM To present a comprehensive review of primary adrenal ES,with emphasis on diagnosis,therapy and oncological outcomes.METHODS A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020.PubMed/MEDLINE,EMBASE and Google Scholar bibliographic databases were searched to identify articles from 1989 to 2022 and included patients with ES/primitive neuroectodermal tumor(PNET)of the adrenal gland.PubMed,Google Scholar and EMBASE medical databases were searched,combining the terms“adrenal”,“ES”and“PNET”.Demographic,clinical,pathological and oncological data of patients were analyzed by SPSS version 29.0.RESULTS A total of 52 studies were included for review(47 case reports and 5 case series)with 66 patients reported to have primary adrenal ES.Mean age at diagnosis was 26.4±15.4 years(37.9%males,57.6%females,sex not reported in 3 cases).The most frequent complaint was abdominal/flank pain or discomfort(46.4%)followed by a palpable mass(25.0%),and the average duration of symptoms was 2.6±3.1 mo.The imaging modality of choice was computed tomography scan(81.5%),followed by magnetic resonance imaging(20.4%).Preoperative staging revealed that 17 tumors(27.9%)were metastatic and 14 patients had inferior vena cava or renal vein neoplastic thrombus at initial diagnosis.Open adrenalectomy was performed in the majority of cases(80.0%),of which 27.9%required more extensive resection.Minimally invasive surgery was attempted in 8.2%of tumors.Complete surgical resection was achieved in 89.4%of the patients.Adjuvant therapy was administered to 32 patients,in the form of chemotherapy(62.5%),radiotherapy(3.1%)or combination(34.4%).Median overall survival was 15 mo and 24-mo overall survival was 40.5%.Median disease-free survival was 10 mo and 24-mo disease-free survival was 33.3%.CONCLUSION The significant progress in molecular biology and genetics of ES does not reflect on patient outcomes.ES remains an aggressive tumor with a poor prognosis and high mortality.展开更多
文摘For more than a half century, my colleagues and I in the Stony Brook High Pressure Laboratory have profited from collaborations with French scientists in their laboratories in Orsay, Paris, Toulouse, Lille, Lyon, Strasbourg and </span><span style="font-family:Verdana;">Rennes. These interactions have included postdoctoral appointments of French colleagues in our laboratory as well as two année sabbatique by me;in 1983-84</span><span style="font-family:Verdana;">, in the Laboratoire de Géophysique et Géodynamique Interne at the Université Paris XI in Orsay and in 2020-2003 in the Laboratoire des Méchanismes et Transfert en Géologie at the Université Paul Sabatier in Toulouse. The objective of this report is to relate this history and to illustrate the scientific advances which </span></span><span style="font-family:Verdana;">resulted</span><span style="font-family:Verdana;"> from these collaborations.
文摘For the past half-century, I have been fortunate in maintaining collaborations with Czech scientists in the Czech Republic [formerly Czechoslovakia] from the Geofyzikální ústav-GFU [Institute of Geophysics] of the <span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">eskoslovenská Akademie Věd-</span><span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">SAV [Czechoslovak Academy of Sciences]. These collaborations have included exchange visits by me to Prague [Praha] and convening international workshops in 1976, 1986 and 1996 in castles used by the </span><span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">SAV as well as visits by Czech colleagues to Stony Brook University. The objective of this report is to relate this history. This paper is dedicated to the memory of Vladislav Babu</span><span style="font-family:Verdana;">?</span><span style="font-family:Verdana;">ka.</span>
基金Department of Navy Awards N00014-22-1-2001 and N00014-23-1-2124 issued by the Office of Naval Research。
文摘The power grid is undergoing a transformation from synchronous generators(SGs) toward inverter-based resources(IBRs). The stochasticity, asynchronicity, and limited-inertia characteristics of IBRs bring about challenges to grid resilience. Virtual power plants(VPPs) are emerging technologies to improve the grid resilience and advance the transformation. By judiciously aggregating geographically distributed energy resources(DERs) as individual electrical entities, VPPs can provide capacity and ancillary services to grid operations and participate in electricity wholesale markets. This paper aims to provide a concise overview of the concept and development of VPPs and the latest progresses in VPP operation, with the focus on VPP scheduling and control. Based on this overview, we identify a few potential challenges in VPP operation and discuss the opportunities of integrating the multi-agent system(MAS)-based strategy into the VPP operation to enhance its scalability, performance and resilience.
基金the National Key Research and Development Program of China(Grant No.2022YFE0106500)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2022076)+1 种基金the National Key Scientific and Technological Infrastructure project“Earth System Numerical Simulation Facility”(EarthLab2023-EL-ZD-00012)。
文摘The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental change.It is extremely important to investigate the interactions among atmospheric CO_(2),the physical climate system,and the carbon cycle of the underlying surface for a better understanding of the Earth system.Earth system models are widely used to investigate these interactions via coupled carbon-climate simulations.The Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0)has successfully fixed a two-way coupling of atmospheric CO_(2)with the climate and carbon cycle on land and in the ocean.Using CAS-ESM2.0,we conducted a coupled carbon-climate simulation by following the CMIP6 proposal of a historical emissions-driven experiment.This paper examines the modeled CO_(2)by comparison with observed CO_(2)at the sites of Mauna Loa and Barrow,and the Greenhouse Gases Observing Satellite(GOSAT)CO_(2)product.The results showed that CAS-ESM2.0 agrees very well with observations in reproducing the increasing trend of annual CO_(2)during the period 1850-2014,and in capturing the seasonal cycle of CO_(2)at the two baseline sites,as well as over northern high latitudes.These agreements illustrate a good ability of CAS-ESM2.0 in simulating carbon-climate interactions,even though uncertainties remain in the processes involved.This paper reports an important stage of the development of CAS-ESM with the coupling of carbon and climate,which will provide significant scientific support for climate research and China’s goal of carbon neutrality.
文摘Within the last few decades, increases in computational resources have contributed enormously to the progress of science and engineering (S & E). To continue making rapid advancements, the S & E community must be able to access computing resources. One way to provide such resources is through High-Performance Computing (HPC) centers. Many academic research institutions offer their own HPC Centers but struggle to make the computing resources easily accessible and user-friendly. Here we present SHABU, a RESTful Web API framework that enables S & E communities to access resources from Boston University’s Shared Computing Center (SCC). The SHABU requirements are derived from the use cases described in this work.
文摘BACKGROUND Irritable bowel syndrome(IBS)is the most prevalent gastrointestinal disorder in developed countries and reduces patients’quality of life,hinders their ability to work,and increases health care costs.A growing number of trials have demonstrated an aberrant gut microbiota composition in IBS,also known as‘gut dysbiosis’.Fecal microbiota transplantation(FMT)has been suggested as a treatment for IBS.AIM To assess the efficacy and safety of FMT for the treatment of IBS.METHODS We searched Cochrane Central,MEDLINE,EMBASE and Web of Science up to 24 October 2022 for randomised controlled trials(RCTs)investigating the effectiveness of FMT compared to placebo(including autologous FMT)in treating IBS.The primary outcome was the number of patients with improvements of symptoms measured using a validated,global IBS symptoms score.Secondary outcomes were changes in quality-of-life scores,non-serious and serious adverse events.Risk ratios(RR)and corresponding 95%CI were calculated for dichotomous outcomes,as were the mean differences(MD)and 95%CI for continuous outcomes.The Cochrane risk of bias tool was used to assess the quality of the trials.GRADE criteria were used to assess the overall quality of the evidence.RESULTS Eight RCTs(484 participants)were included in the review.FMT resulted in no significant benefit in IBS symptoms three months after treatment compared to placebo(RR 1.19,95%CI:0.68-2.10).Adverse events were reported in 97 participants in the FMT group and in 45 participants in the placebo group(RR 1.17,95%CI:0.63-2.15).One serious adverse event occurred in the FMT group and two in the placebo group(RR 0.42,95%CI:0.07-2.60).Endoscopic FMT delivery resulted in a significant improvement in symptoms,while capsules did not.FMT did not improve the quality of life of IBS patients but,instead,appeared to reduce it,albeit non significantly(MD-6.30,95%CI:-13.39-0.79).The overall quality of the evidence was low due to moderate-high inconsistency,the small number of patients in the studies,and imprecision.CONCLUSION We found insufficient evidence to support or refute the use of FMT for IBS.Larger trials are needed.
文摘Mechanical metamaterials such as auxetic materials have attracted great interest due to their unusual properties that are dictated by their architectures.However,these architected materials usually have low stiffness because of the bending or rotation deformation mechanisms in the microstructures.In this work,a convolutional neural network(CNN)based self-learning multi-objective optimization is performed to design digital composite materials.The CNN models have undergone rigorous training using randomly generated two-phase digital composite materials,along with their corresponding Poisson's ratios and stiffness values.Then the CNN models are used for designing composite material structures with the minimum Poisson's ratio at a given volume fraction constraint.Furthermore,we have designed composite materials with optimized stiffness while exhibiting a desired Poisson's ratio(negative,zero,or positive).The optimized designs have been successfully and efficiently obtained,and their validity has been confirmed through finite element analysis results.This self-learning multi-objective optimization model offers a promising approach for achieving comprehensive multi-objective optimization.
基金supported by the National Offshore Wind Research and Development Consortium (NOWRDC) under agreement number 147503a grant from the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) under the Water Power Technologies Office (WPTO) Award Number DE-EE0009450
文摘This study proposes a cost-effective machine-learning based model for predicting velocity and turbulence kineticenergy fields in the wake of wind turbines for yaw control applications.The model consists of an auto-encoderconvolutional neural network(ACNN)trained to extract the features of turbine wakes using instantaneous datafrom large-eddy simulation(LES).The proposed framework is demonstrated by applying it to the Sandia NationalLaboratory Scaled Wind Farm Technology facility consisting of three 225 kW turbines.LES of this site is performedfor different wind speeds and yaw angles to generate datasets for training and validating the proposed ACNN.It is shown that the ACNN accurately predicts turbine wake characteristics for cases with turbine yaw angleand wind speed that were not part of the training process.Specifically,the ACNN is shown to reproduce thewake redirection of the upstream turbine and the secondary wake steering of the downstream turbine accurately.Compared to the brute-force LES,the ACNN developed herein is shown to reduce the overall computational costrequired to obtain the steady state first and second-order statistics of the wind farm by about 85%.
基金supported by DOE DE-FG02-87ER40331funded by the Deutsche Forschungsgemeinschaft (DFG,German Research Foundation) under Germanys Excellence Strategy EXC2181/1-390900948 (the Heidelberg STRUCTURES Excellence Cluster),within the Collaborative Research Center SFB1225 (ISOQUANT,Project-ID 273811115)。
文摘Valuable information on dynamics of expanding fluids can be inferred from the response of such systems to perturbations in their initial geometry.We apply this technique in high-energy^(96)Ru+^(96)Ru and^(96)Zr+^(96)Zr collisions to scrutinize the expansion dynamics of the quark-gluon plasma,where the initial geometry perturbations are sourced by the differences in deformations and radial profiles between^(96)Ru and^(96)Zr,and the collective response is captured by the change in anisotropic flow Vn between the two collision systems.Using a transport model,we analyze how the nonlinear coupling between lower-order flow harmonics V_(2)and V_(3)to the higher-order flow harmonics V_(4)and V_(5),expected to scale as V_(4)NL= χ_(4)V_(2)2and V_(5)NL= χ_(5)V_(2)V_(3),gets modified as one moves from^(96)Ru+^(96)Ru to^(96)Zr+^(96)Zr systems.We find that these scaling relations are valid to high precision:variations of order 20% in V_(4)NLand V_(5)NLdue to differences in quadrupole deformation,octupole deformation,and nuclear skin modify χ_(4)and χ_(5)by about 1–2%.Percent-level deviations are however larger than the expected experimental uncertainties and could be measured.Therefore,collisions of isobars with different nuclear structures are a unique tool to isolate subtle nonlinear effects in the expansion of the quark-gluon plasma that would be otherwise impossible to access in a single collision system.
基金This work was supported in part by the National Natural Science Foundation of China under Grant 61872408the Natural Science Foundation of Hunan Province under Grant 2020JJ4238+1 种基金the Social Science Foundation of Hunan Province under Grant 19YBA098the Research Fund of Hunan provincial key laboratory of informationization technology for basic education under Grant 2015TP1017.
文摘Few previous Reversible Visible Watermarking(RVW)schemes have both good transparency and watermark visibility.An adaptive RVW scheme that integrates Total Variation and visual perception in Block Truncation Coding(BTC)compressed domain,called TVB-RVW is proposed in this paper.A new mean image estimation method for BTC-compressed images is first developed with the help of Total Variation.Then,a visual perception factor computation model is devised by fusing texture and luminance characteristics.An adaptive watermark embedding strategy is used to embed the visible watermark with the effect of the visual perception factor in the BTC domain.Moreover,a lossless embedding method of the encrypted visible watermark is exploited to deter illegal watermark removal.The visible watermark can be removed since the visual perception factor and the estimated mean image remain unchanged before and after watermark embedding.Extensive experiments validate the superiority of the proposed algorithm over previous RVW schemes in BTC in terms of the visual quality of watermarked images and watermark visibility,and it can achieve a good balance between transparency and watermark visibility.
文摘Background In this work,we focus on the label layout problem:specifying the positions of overlaid virtual annotations in Virtual/Augmented Reality scenarios.Methods Designing a layout of labels that does not violate domain-specific design requirements,while at the same time satisfying aesthetic and functional principles of good design,can be a daunting task even for skilled visual designers.Presenting the annotations in 3D object space instead of projection space,allows for the preservation of spatial and depth cues.This results in stable layouts in dynamic environments,since the annotations are anchored in 3D space.Results In this paper we make two major contributions.First,we propose a technique for managing the layout and rendering of annotations in Virtual/Augmented Reality scenarios by manipulating the annotations directly in 3D space.For this,we make use of Artificial Potential Fields and use 3D geometric constraints to adapt them in 3D space.Second,we introduce PartLabeling:an open source platform in the form of a web application that acts as a much-needed generic framework allowing to easily add labeling algorithms and 3D models.This serves as a catalyst for researchers in this field to make their algorithms and implementations publicly available,as well as ensure research reproducibility.The PartLabeling framework relies on a dataset that we generate as a subset of the original PartNet dataset consisting of models suitable for the label management task.The dataset consists of 10003D models with part annotations.
文摘BACKGROUND Ewing sarcoma(ES)is a malignant neoplasm of neuroectodermal origin and is commonly observed in children and young adults.The musculoskeletal system is the main body system impacted and ES is rarely seen in the visceral organs particularly the adrenal gland.AIM To present a comprehensive review of primary adrenal ES,with emphasis on diagnosis,therapy and oncological outcomes.METHODS A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020.PubMed/MEDLINE,EMBASE and Google Scholar bibliographic databases were searched to identify articles from 1989 to 2022 and included patients with ES/primitive neuroectodermal tumor(PNET)of the adrenal gland.PubMed,Google Scholar and EMBASE medical databases were searched,combining the terms“adrenal”,“ES”and“PNET”.Demographic,clinical,pathological and oncological data of patients were analyzed by SPSS version 29.0.RESULTS A total of 52 studies were included for review(47 case reports and 5 case series)with 66 patients reported to have primary adrenal ES.Mean age at diagnosis was 26.4±15.4 years(37.9%males,57.6%females,sex not reported in 3 cases).The most frequent complaint was abdominal/flank pain or discomfort(46.4%)followed by a palpable mass(25.0%),and the average duration of symptoms was 2.6±3.1 mo.The imaging modality of choice was computed tomography scan(81.5%),followed by magnetic resonance imaging(20.4%).Preoperative staging revealed that 17 tumors(27.9%)were metastatic and 14 patients had inferior vena cava or renal vein neoplastic thrombus at initial diagnosis.Open adrenalectomy was performed in the majority of cases(80.0%),of which 27.9%required more extensive resection.Minimally invasive surgery was attempted in 8.2%of tumors.Complete surgical resection was achieved in 89.4%of the patients.Adjuvant therapy was administered to 32 patients,in the form of chemotherapy(62.5%),radiotherapy(3.1%)or combination(34.4%).Median overall survival was 15 mo and 24-mo overall survival was 40.5%.Median disease-free survival was 10 mo and 24-mo disease-free survival was 33.3%.CONCLUSION The significant progress in molecular biology and genetics of ES does not reflect on patient outcomes.ES remains an aggressive tumor with a poor prognosis and high mortality.