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World Journal of Gastroenterology 2007年第38期13卷 5116-5120页

作者： Michael Economou Grigoris Filis Zoi Tsianou John Alamanos antonios kogevinas Kostas Masalas Anna Petrou Epameinondas V Tsianos 1st Department of Internal Medicine and Hepato- gastroenterology Unit University of Ioannina School of Medicine Ioannina Greece Department of Hygiene and Epidemiology University of Ioannina School of Medicine Ioannina Greece

AIM: To assess the trends in the incidence of inflammatory bowel disease (IBD) over 23 years in the same area and to identify genetic factors related to incidence evolution. METHODS: Patients with IBD arising from North- western Greece were systematically recorded through the 1983-2005 period. Trends in disease incidence and genetic patterns related to CARD15 variants were documented and correlated. RESULTS: A total of 447 patients with IBD were recorded (23.5% Crohn’s disease, 72.7% Ulcerative colitis and 3.8% indeterminate colitis). Mean annual incidence rates of CD and UC were 0.9/100 000 (95% CI 0.1-1.7) and 2.7/100 000 (95% CI 1.7-4.1) inhabitants, respectively. There was a statistically significant increase of CD incidence (P < 0.01) during the study period, in contrast to the UC incidence. There were no statistical differences in CARD15 variants over the study period. CONCLUSION: The incidence of CD in North-western Greece has risen disproportionately to that of UC in the 21st century. This is not related to alterations of genetic background though.

关键词： Inflammatory bowel disease Crohn's disease Epidemiology CARD15

3D micropattern force regulates stem cell function

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National Science Review 2023年第8期10卷 69-70页

作者： antonios G. Mikos Department of Bioengineering Rice University

Biophysical cues of the cellular microenvironment significantly influence cell behaviors by mechanotransduction [1,2].For example, the mechanical properties of the extracellular matrix modulate human mesenchymal stem ...

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Deleting Outliers in Robust Regression with Mixed Integer Programming

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Acta Mathematicae Applicatae Sinica 2005年第2期21卷 323-334页

作者： Georgios Zioutas antonios Avramidis Division of Computational Methods and Computer Programming General Department Faculty of Technology Aristotle University of Thessaloniki 541 24 Thessaloniki GreeceDivision of Computational Methods and Computer Programming General Department Faculty of Technology Aristotle University of Thessaloniki 541 24 Thessaloniki Greece

In robust regression we often have to decide how many are the unusualobservations, which should be removed from the sample in order to obtain better fitting for the restof the observations. Generally, we use the basic principle of LTS, which is to fit the majority ofthe data, identifying as outliers those points that cause the biggest damage to the robust ***, in the LTS regression method the choice of default values for high break down-point affectsseriously the efficiency of the estimator. In the proposed approach we introduce penalty cost fordiscarding an outlier, consequently, the best fit for the majority of the data is obtained bydiscarding only catastrophic observations. This penalty cost is based on robust design weights andhigh break down-point residual scale taken from the LTS estimator. The robust estimation is obtainedby solving a convex quadratic mixed integer programming problem, where in the objective functionthe sum of the squared residuals and penalties for discarding observations is minimized. Theproposed mathematical programming formula is suitable for small-sample data. Moreover, we conduct asimulation study to compare other robust estimators with our approach in terms of their efficiencyand robustness.

关键词： Robust regression quadratic mixed integer programming least trimmedsquares deleting outliers penalty methods

High-fidelity trajectory optimization for aeroassisted vehicles using variable order pseudospectral method

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Chinese Journal of Aeronautics 2021年第1期34卷 237-251页

作者： Runqi CHAI antonios TSOURDOS AI SAVVARIS Senchun CHAI Yuanqing XIA School of Aerospace Transport and ManufacturingCranfield UniversityBedfordshire MK43OALUnited Kingdom School of Automation Beijing Institute of TechnologyBeijing 100081China

In this study,the problem of time-optimal reconnaissance trajectory design for the aeroassisted vehicle is *** from most works reported previously,we explore the feasibility of applying a high-order aeroassisted vehicle dynamic model to plan the optimal flight trajectory such that the gap between the simulated model and the real system can be narrowed.A highly-constrained optimal control model containing six-degree-of-freedom vehicle dynamics is *** solve the formulated high-order trajectory planning model,a pipelined optimization strategy is *** approach is based on the variable order Radau pseudospectral method,indicating that the mesh grid used for discretizing the continuous system experiences several adaption *** of such a strategy can potentially smooth the flight trajectory and improve the algorithm convergence *** simulations are reported to demonstrate some key features of the optimized flight trajectory.A number of comparative studies are also provided to verify the effectiveness of the applied method as well as the high-order trajectory planning model.

关键词： Aeroassisted vehicle High-order Radau pseudospectral method Six-degree-of-freedom Trajectory design Variable order

A numerical case study on the long-term seismic assessment of reinforced concrete tunnels in corrosive environments

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 551-572页

作者： Maria Antoniou antonios Mantakas Nikolaos Nikitas Raul Fuentes ETH Zurich ZurichSwitzerland National Technical University of Athens AthensGreece University of Leeds LeedsUK RWTH Aachen University AachenGermany

The paper investigates the long-term seismic behaviour of an underground reinforced concrete(RC)metro tunnel in Santiago,Chile,considering the combined effects of chloride-induced corrosion and cumulative,low-amplitude seismic shaking on the structure’s *** soil-tunnel response is evaluated with the aid of transient,nonlinear finite element analysis using a two-dimensional(2D)plane strain numerical model that adopts advanced nonlinear models for the simulation of soil and concrete plasticity and the dynamic stiffness *** effects of corrosion deterioration are demonstrated in terms of time-dependent loss of rebar area and cover concrete stiffness and *** study illustrates the influence of ageing and repeated seismic shaking on lining deformation,crack development,and the modal characteristics of the intact and degrading *** results indicate that multiple lowamplitude events drive the non-degrading RC tunnel beyond its elastic regime without significant structural response consequences.A noticeable impact of corrosion deterioration on the structure’s seismic performance is revealed,increasing with the number and intensity of earthquake *** different tunnel embedment depths are comparatively *** analyses demonstrate larger coseismic section convergence in the case of the deeper tunnel,yet a less pronounced effect of ageing and successive seismic loading compared to the shallow section,which is evident in the RC lining cracks at the end of shaking.

关键词： Tunnels Reinforcement corrosion Ageing Earthquakes Numerical modelling Long-term performance Concrete cracking behaviour

Advances in In Vitro and In Vivo Bioreactor-Based Bone Generation for Craniofacial Tissue Engineering

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Biomedical Engineering Frontiers 2023年第1期4卷 203-216页

作者： Emma Watson antonios G.Mikos Department of Bioengineering Rice UniversityHoustonTX 77030USA

Craniofacial reconstruction requires robust bone of specified geometry for the repair to be both functional and *** native bone from elsewhere in the body can be harvested,shaped,and implanted within a defect,using either an in vitro or in vivo bioreactors eliminates donor site morbidity while increasing the customizability of the generated *** vitro bioreactors utilize cells harvested from the patient,a scaffold,and a device to increase mass transfer of nutrients,oxygen,and waste,allowing for generation of larger viable *** vivo bioreactors utilize the patient’s own body as a source of cells and of nutrient transfer and involve the implantation of a scaffold with or without growth factors adjacent to vasculature,followed by the eventual transfer of vascularized,mineralized tissue to the defect *** different models of in vitro bioreactors exist,and several different implantation sites have been successfully utilized for in vivo tissue generation and defect repair in *** this review,we discuss the specifics of each bioreactor strategy,as well as the advantages and disadvantages of each and the future directions for the engineering of bony tissues for craniofacial defect repair.

关键词： defect implantation utilize

Osteitis pubis in elite athletes:Diagnostic and therapeutic approach

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World Journal of Orthopedics 2015年第9期6卷 672-679页

作者： antonios G Angoules Department of Medical Laboratories Technological Educational Institute of Athens

Osteitis pubis(OP) is a debilitating overuse syndrome characterizing by pelvic pain and local tenderness over the pubic symphysis commonly encountered in athletes often involved in kicking, twisting and cutting activities in sports such as soccer and rugby and to a lesser degree distance running. It is a common source of groin pain in elite athletes attributable to pubis sympysis instability as the result of microtrauma caused by repetitive muscle strains on pubic bones. Diagnosis is based mainly on detailed sports history and a meticulous clinical examination, although occasionally is difficult to distinguish this nosological entity from other pathologies affecting the involved area which may occur concomitantly in the same patient. Radiologic examinations such as plain radiographs, magnetic resonance imaging and 3 phase bone isotope scanning may be helpful to differentiate from other clinical entities with similar clinical presentation. Most cases respond well to conservative treatment which includes several physical modalities and especially a progressive rehabilitation programmed individualized to each one of patients diagnosed with OP. Local injection therapies have been also been proposed as a non-operative therapeutic option for the efficient management of these patients. In refractory cases, surgical therapeutic strategies are warranted. These include several open or minimally invasive surgical interventions such as arthroscopic or open symphysis curettage, wedge or total resection of pubic sympysis, polypropylene mesh placement and pubic fusion. In this review a critical analysis of OP in elite athletes is performed with special focus on current concepts of diagnosis and management of this source of athletic groin pain.

关键词： Osteitis pubis Groin pain Sports overuse injuries Conservative management Surgery

Review of hybrid electric powered aircraft,its conceptual design and energy management methodologies

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Chinese Journal of Aeronautics 2021年第4期34卷 432-450页

作者： Ye XIE Al SAVVARISAL antonios TSOURDOS Dan ZHANG Jason GU Intelligent Robot Research Centre Zhejiang LabHangzhou311100China School of Aerospace Transport and ManufacturingCranfield UniversityBedford MK430ALUnited Kingdom York University North YorkToronto M3J 1P3Canada Dalhousie University HalifaxNova Scotia B3H 4R2Canada

The paper overviews the state-of-art of aircraft powered by hybrid electric propulsion *** research status of the design and energy management of hybrid aircraft and hybrid propulsion systems are further *** first contribution of the review is to demonstrate that,in the context of relatively underdeveloped electrical storage technologies,the study of mid-scale hybrid aircraft can contribute the most to both theoretical and practical ***,the profits and potential drawbacks of applying hybrid propulsion to mid-scale hybrid airplanes have not been thoroughly ***,as summed in the overview of design methodologies,the multi-objective optimization transcends the single-objective *** potential of the hybrid propulsion system can be thoroughly evaluated in only one optimization run,if several objectives optimized *** there are few researches covering the conceptual design of hybrid aircraft using multi-objective *** review of the most popular energy management strategies discloses the third research gap—current methodologies favoured in hybrid ground vehicles do not consider the aircraft ***,both non-causal and causal energy management are needed for performing a complicated flight mission with several sub-tasks.

关键词： Aircraft Convex optimization Energy management Fuzzy logic control Hybrid electric propulsion system Non-dominated sorting genetic algorithm Sizing

Optimal three-dimensional impact time guidance with seeker’s field-of-view constraint

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Chinese Journal of Aeronautics 2021年第2期34卷 240-251页

作者： Shaoming HE Chang-Hun LEE Hyo-Sang SHIN antonios TSOURDOS School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Department of Aerospace Engineering Korea Advanced Institute of Science and TechnologyDaejeon 34141Republic of Korea School of Aerospace Transport and ManufacturingCranfield UniversityCranfiehMK43 OALUnited Kingdom

This paper proposes a new three-dimensional optimal guidance law for impact time control with seeker’s Field-of-View(FOV) constraint to intercept a stationary target. The proposed guidance law is devised in conjunction with the concept of biased Proportional Navigation Guidance(PNG). The guidance law developed leverages a nonlinear function to ensure the boundedness of velocity lead angle to cater to the seeker’s FOV limit. It is proven that the impact time error is nullified in a finite-time under the proposed method. Additionally, the optimality of the biased command is theoretically analyzed. Numerical simulations confirm the superiority of the proposed method and validate the analytic findings.

关键词： Applied optimal control Field-of-view constraint Impact time control Missile guidance Optimal error dynamics

CNN-based novelty detection for terrestrial and extra-terrestrial autonomous exploration

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IET Cyber-Systems and Robotics 2021年第2期3卷 116-127页

作者： Loukas Bampis antonios Gasteratos Evangelos Boukas Department of Production and Management Engineering Democritus University of ThraceXanthiGreece Department of Electrical Engineering Technical University of DenmarkKongens LyngbyDenmark

Novelty detection is concerned with detecting features that do not belong to any known class or are not well represented by existing ***,in autonomous navigation novelty detection determines whether an input camera frame contains certain entities of high interest which do not correspond to a known *** of the key requirements for the future space exploration missions is the reduction of the information to be transferred back to ***,novelty detection techniques have been developed to select the subset of acquired images with significant measurements that justify utilisation of the limited bandwidth from the available information *** methods are based on the identification of salient regions,which are then evaluated against a set of trained *** explore a novelty detection approach,based on the reasoning properties of Neural Networks,which follow the same guidelines while also being trainable in an end-to-end *** characteristic allows for the intertwined optimisation of the individual components leading to a closer estimation of a global *** experiments reveal that the proposed novelty detection system achieves better performance,as compared to handcrafted techniques,when the learning and testing examples refer to similar environments.

关键词： solution. autonomous closer