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共反射面叠加法

石油物探译丛 2001年第3期 1-11页

作者： r.jger 姚云霞李振春石油大学资源系山东东营257061

共反射面(CrS)叠加提供一种从多次覆盖反射数据进行零偏移距(ZO)模拟的方法,它不依赖于速度信息。而常规成像方法(如NMO/DMO叠加、叠前深度偏移)都需要一个准确的宏观速度模型。我们把CrS叠加应用于2D合成地震数据,得到1个高质量的模... 详细信息

共反射面(CrS)叠加提供一种从多次覆盖反射数据进行零偏移距(ZO)模拟的方法,它不依赖于速度信息。而常规成像方法(如NMO/DMO叠加、叠前深度偏移)都需要一个准确的宏观速度模型。我们把CrS叠加应用于2D合成地震数据,得到1个高质量的模拟ZO剖面以及3个重要的运动学波场属性剖面。波场属性可用来建立一2D宏观速度模型。我们用正演模拟对多次覆盖数据给出的属性与模型属性作比较,验证了CrS叠加理论和所得属性的正确性。对2D资料应用CrS叠加,可产生CrS叠加面,它依赖于3个参数,它们是ZO射线的出射角α,以及与ZO有关的两个波前曲率半径r_N和r_(NIP),即法向波和法向入射点波的波前曲率半径。对每一ZO样点可确定一组最佳参数,这组参数能使CrS走时面最好地拟合反射同相轴。兼顾CrS叠加的效果和效率,采用最优化方法求取所有零炮检距样点的全部最佳参数。对于CrS流程的实现,使用CrS叠加面的双曲二阶泰勒展式,因为这一表达式不仅适合于处理不规则的采集观测系统,而且更有利于3参数的寻优。此外,双曲走时展式在特定道集(如CMP道集和ZO剖面)上可简化,因而能够给出不同的观测方案。

关键词：共反射面叠加零偏移距全局优化地震勘探

Gene therapy for spinal muscular atrophy:perspectives on the possibility of optimizing SMN1 delivery to correct all neurological and systemic perturbations

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Neural regeneration research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown rafael j.Yáñez-Muñoz Heidi r.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

Machine Learning Techniques in Predicting Hot Deformation Behavior of Metallic Materials

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela josef Walek jaromír Kopecek Department of Metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.

关键词： Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Experimental investigations of a full model with adaptive elasto-flexible membrane wings

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Chinese journal of Aeronautics 2021年第7期34卷 211-218页

作者： jonathan PFLU ger Christian BrEITSAMTEr Chair of Aerodynamics and Fluid Mechanics Technical University of MunichGarching 85748Germany

The morphing wing concept aims to constantly adapt the aerodynamics to different flight *** wing is able to adapt to different flight conditions by an adjustable Aspect ratio(Ar)and sweep.A high Ar configuration provides high aerodynamic efficiency,while a low Ar configuration,with highly swept wings offers a good ***,the flexible membrane allows the wing surface to stretch and contract in-plane as well as the airfoil to adapt to different aerodynamic *** the context of this work,the aerodynamic characteristics of a full model with form-adaptive elasto-flexible membrane wings are investigated *** focus is on the high-lift regime and on the analysis of the aerodynamic coefficients as well as their ***,the lateral aerodynamic derivatives at asymmetric wing positions are of interest.

关键词： Experimental aerodynamics Flexible wing surface Force and moment measurements Morphing wing Particle image velocimetry

Automatic route planning for GPS art generation

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Computational Visual Media 2019年第3期5卷 303-310页

作者： Andre Waschk jens Krüger University of Duisburg-Essen

In this paper, we present a novel approach to automated route generation of global positioning system(GPS) artwork. The term GPS artwork describes the generation of drawings by leaving virtual traces on digital maps. Until now, the creation of these images has required a manual planning phase in which an artist designs the route by hand. Once the route for this artwork has been planned, GPS devices have been used to track the movement. Using our solution, the lengthy planning phase can be significantly shortened,thereby opening art creation to a broader public.

关键词： GPS art walking routing shape detection navigation

Emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

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Neural regeneration research 2025年第9期20卷 2591-2593页

作者： Alena Salasova Anders Nykjær Danish research Institute of Translational Neuroscience DANDrITE-Nordic EMBL Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2

Gust response of an elasto-flexible morphing wing using fluid–structure interaction simulations

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Chinese journal of Aeronautics 2024年第2期37卷 45-57页

作者： jonathan PFLÜger Christian BrEITSAMTEr Department of Mechanical Engineering Technical University of MunichGarching 85748Germany

Small and micro unmanned aircraft are the focus of scientific interest due to their wide range of *** often operate in a highly unstable flight environment where the application of new morphing wing technologies offers the opportunity to improve flight *** investigated concept comprises port and starboard adjustable wings,and an adaptive elastoflexible membrane serves as the lifting *** focus is on the benefits of the deforming membrane during the impact of a one-minus-cosine type *** a low reynolds number of re=264000,the morphing wing model is investigated numerically by unsteady fluid-structure interaction ***,the numerical results are validated by experimental data from force and moment,flow field,and deformation ***,with the rigid wing as the baseline,the flexible case is investigated,focusing on the advantages of the elastic *** all configurations studied,the maximum amplitude of the lift coefficient under gust load shows good agreement between the experimental and numerical *** the decay of the gust,they differ more the higher the aspect ratio of the *** considering the flow field,the main differences are due to the separation behavior on the upper side of the *** flow reattaches earlier in the experiments than in the simulations,which explains the higher lift values observed in the *** at one intermediate configuration does the lift amplitude of the rigid configuration exceeds that of the flexible by about 12%,with the elastic membrane resulting in a smaller and more uniform peak load,which is also evident in the wing loading and hence in the root bending moment.

关键词： Membrane wing Morphing wing Flexible wing surface Computational fluid dynam-ics Fluid-structure interaction Unsteady inflow condition Gust response

Targeting cell death signaling in colorectal cancer:Current strategies and future perspectives

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World journal of Gastroenterology 2014年第8期20卷 1923-1934页

作者： Bruno Christian Koehler Dirk jger Henning Schulze-Bergkamen National Center for Tumor Diseases University Hospitals Heidelberg69120 HeidelbergGermany

The evasion from controlled cell death induction has been considered as one of the hallmarks of cancer cells. Defects in cell death signaling are a fundamental phenomenon in colorectal cancer. Nearly any non-invasive cancer treatment finally aims to induce cell death. However, apoptosis resistance is the major cause for insufficient therapeutic success and disease relapse in gastrointestinal oncology. Various compounds have been developed and evaluated with the aim to meet with this obstacle by triggering cell death in cancer cells. The aim of this review is to illustrate current approaches and future directions in targeting cell death signaling in colorectal cancer. The complex signaling network of apoptosis will be demonstrated and the “druggability” of targets will be identified. In detail, proteins regulating mitochondrial cell death in colorectal cancer, such as Bcl-2 and survivin, will be discussed with respect to potential therapeutic exploitation. Death receptor signaling and targeting in colorectal cancer will be outlined. Encouraging clinical trials including cell death based targeted therapies for colorectal cancer are under way and will be demonstrated. Our conceptual understanding of cell death in cancer is rapidly emerging and new types of controlled cellular death have been identified. To meet this progress in cell death research, the implication of autophagy and necroptosis for colorectal carcinogenesis and therapeutic approaches will also be depicted. The main focus of this topic highlight will be on the revelation of the complex cell death concepts in colorectal cancer and the bridging from basic research to clinical use.

关键词： Colorectal cancer Apoptosis Necroptosis Autophagy Clinical trial Bcl-2 proteins BH-3 mimetics Inflammatory bowel disease

Epigenetics and pancreatic cancer:Pathophysiology and novel treatment aspects

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World journal of Gastroenterology 2014年第24期20卷 7830-7848页

作者： Daniel Neureiter Tarkan jger Matthias Ocker Tobias Kiesslich Institute of Pathology Paracelsus Medical University/Salzburger Landeskliniken (SALK)5020 SalzburgAustria Department of Surgery Paracelsus Medical University/Salzburger Landeskliniken (SALK)5020 SalzburgAustria Experimental Medicine Oncology Bayer Pharma AG13342 BerlinGermany Department of Internal Medicine I Paracelsus Medical University/Salzburger Landeskliniken (SALK)5020 SalzburgAustria Institute of Physiology and Pathophysiology Paracelsus Medical University5020 SalzburgAustria

An improvement in pancreatic cancer treatment represents an urgent medical goal. Late diagnosis and high intrinsic resistance to conventional chemotherapy has led to a dismal overall prognosis that has remained unchanged during the past decades. Increasing knowledge about the molecular pathogenesis of the disease has shown that genetic alterations, such as mutations of K-ras, and especially epigenetic dysregulation of tumor-associated genes, such as silencing of the tumor suppressor p16ink4a, are hallmarks of pancreatic cancer. Here, we describe genes that are commonly affected by epigenetic dysregulation in pancreatic cancer via DNA methylation, histone acetylation or mirNA (microrNA) expression, and review the implications on pancreatic cancer biology such as epithelial-mesenchymal transition, morphological pattern formation, or cancer stem cell regulation during carcinogenesis from PanIN (pancreatic intraepithelial lesions) to invasive cancer and resistance development. Epigenetic drugs, such as DNA methyltransferases or histone deactylase inhibitors, have shown promising preclinical results in pancreatic cancer and are currently in early phases of clinical development. Combinations of epigenetic drugs with established cytotoxic drugs or targeted therapies are promising approaches to improve the poor response and survival rate of pancreatic cancer patients.

关键词： Pancreatic cancer Epigenetics DNA methylation Histone modification microrNA Targeted therapy Epithelial-mesenchymal transition