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Lipoprotein-associated phospholipase A2 prognostic role in atherosclerotic complications

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World Journal of Cardiology 2015年第10期7卷 609-620页

作者： Giuseppe Maiolino Valeria Bisogni Giacomo rossitto gian paolo rossi Department of Medicine - DIMED Hypertension Clinic University of Padua

Atherosclerosis manifests itself clinically at advanced stages when plaques undergo hemorrhage and/or rupture with superimposed thrombosis, thus abruptly stopping blood supply. Identification of markers of plaque destabilization at a pre-clinical stage is, therefore, a major goal of cardiovascular research. Promising results along this line were provided by studies investigating the lipoprotein-associated phospholipase A2(Lp-PLA2), a member of phospholipase A2 proteins family that plays a key role in the metabolism of pro-inflammatory phospholipids, as oxidized low-density lipoproteins, and in the generation of pro-atherogenic metabolites, including lysophosphatidylcholine and oxidized free fatty acids. We herein review the experimental and clinical studies supporting use of Lp-PLA2 activity for predicting cardiovascular events. To his end we considered not only Lp-PLA2 activity and mass, but also Lp-PLA2 gene variations and their association with incident coronary artery disease, stroke, and cardiovascular mortality. Based on these evidences the major scientific societies have included in their guidelines the measurement of Lp-PLA2 activity among the biomarkers that are useful in risk stratification of adult asymptomatic patients at intermediate cardiovascular risk. The results of two recently published major clinical trials with the LpPLA2 inhibitor darapladib, which seem to challenge the pathogenic role of Lp-PLA2, will also be discussed.

关键词： Lipoprotein-associated phospholipase A2 Atheroscle

Optimal weakening and damping using polynomial control for seismically excited nonlinear structures

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 607-616页

作者： gian paolo Cimellaro Department of Structural & Geotechnical Engineering(DISTR)

This paper presents an approach for the optimal design of a new retrofit technique called weakening and damping that is valid for civil engineering inelastic structures. An alternative design methodology is developed with respect to the existing ones that is able to determine the locations and the magnitude of weakening and/or softening of structural elements and adding damping while insuring structural stability. An optimal polynomial controller that is a summation of polynomials in nonlinear states is used in Phase I of the method to reduce the peak response quantities of seismically excited nonlinear or hysteretic systems. The main advantage of the optimal polynomial controller is that it is able to automatically stabilize the structural system. The optimal design of a shear-type structure is used as an example to illustrate the feasibility of the proposed approach, which leads to a reduction of both peak inter-story drifts and peak total accelerations.

关键词： weakening and damping optimal design optimal polynomial controller inter-story drift acceleration

Spectral and fragility evaluations of retrofitted structures through strength reduction and enhanced damping

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Earthquake Engineering and Engineering Vibration 2009年第1期8卷 115-125页

作者： gian paolo Cimellaro Hwasung Roh Alessandro De Stefano Department of Structural & Geotechnical Engineering (DISTR) Polytechnic of Turin Turin Italy Department of Civil Structural & Environmental Engineering University at Buffalo The State University of New York Buffalo USA

A retrofit procedure for existing buildings called the ＂weakening and damping technique＂（WED） is presented in this paper. Weakening of structures can limit the maximum response accelerations during severe ground motions, but leads to an increase in the displacements or inter-story drifts. Added damping by using viscous dampers, on the other hand, reduces the inter-story drifts and has no significant effect on total accelerations, when structures behave inelastically. The weakening and damping technique addresses the two main causes for both structural and nonstructural damage in structures. The weakening retrofit is particularly suitable for structures that have overstressed components and weak brittle components. In this paper, the advantages of the WeD are verified by nonlinear dynamic analysis and simplified spectral approach that has been modified to fit structures with additional damping devices. A hospital structure located in the San Fernando Valley in California is selected as a case study. The results from both analyses show that the retrofit solution is feasible to reduce both structural acceleration and displacement. A sensitivity analysis is also carried out to evaluate the effectiveness of the retrofitting method using different combinations of performance thresholds in accelerations and displacements through fragility analysis.

关键词： weakening damping retrofit inelastic spectral response fragility analysis nonlinear dynamic analysis

Discovery of an unknown conduction mechanism in insulating polymers

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High Voltage 2020年第4期5卷 403-408页

作者： gian Carlo Montanari paolo Seri Leonard A.Dissado Center for Advanced Power Systems Florida State University2000 Levy AvenueFL 32310USA DEI University of BolognaViale del Risorgimento2–40136BolognaItaly Department of Engineering University of LeicesterUniversity RoadLeicesterLE17RHUK

Polymer dielectrics are widely used in electrical and electronic apparatus and devices because of their capability to insulate conductors,withstand high fields and suffer negligible conductive *** near-to-zero conductivity has been explained in terms of long-accepted theories of electronic and ionic transport that lead to the accumulation of local net charge regions at high electric *** the authors describe a previously unknown conduction mechanism consisting of small bipolar ultra-fast charge pulses crossing the polymer with the mobility,as large as,4 to 5 orders of magnitude greater than that of the previously *** authors show that this motion is a consequence of molecular relaxation processes triggered by the electric field locally enhanced by the pulses *** accumulation at the electrodes increases interface field and thus contributes substantially towards premature failure in insulating dielectrics in DC fields.

关键词： conduction mechanism negligible

Introspection on improper seismic retrofit of Basilica Santa Maria di Collemaggio after 2009 Italian earthquake

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Earthquake Engineering and Engineering Vibration 2011年第1期10卷 153-161页

作者： gian paolo Cimellaro Andrei M. Reinhorn Alessandro De Stefano Department of Structural & Geotechnical Engineering (DISTR) Politecnico di Torino Department of Civil Structural & Environmental Engineering University at Buffalo The State University of New York

The 2009 L’Aquila, Italy earthquake highlighted the seismic vulnerability of historic masonry building structures due to improper ＂strengthening＂ retrofit work that has been done in the last 50 years. Italian seismic standards recommend the use of traditional reinforcement techniques such as replacing the original wooden roof structure with new reinforced concrete （RC） or steel elements, inserting RC tie-beams in the masonry and new RC floors, and using RC jacketing on the shear walls. The L’Aquila earthquake revealed the numerous limitations of these interventions, because they led to increased seismic forces （due to greater additional weight） and to deformation incompatibilities of the incorporated elements with the existing masonry walls. This paper provides a discussion of technical issues pertaining to the seismic retrofit of the Santa Maria di Collemaggio Basilica and in particular, the limitations of the last （2000） retrofit intervention. Considerable damage was caused to the church because of questionable actions and incorrect and improper technical choices.

关键词： seismic vulnerability historic masonry building wooden roof structure seismic retrofit L’Aquila earthquake

Modelling infrastructure interdependencies and cascading effects using temporal networks

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Resilient Cities and Structures 2024年第3期3卷 28-42页

作者： gian paolo Cimellaro Alessandro Cardoni Andrei Reinhorn Department of Structural Geotechnical and Building EngineeringPolitecnico di TorinoCorso Duca degli Abruzzi 2410129TurinItaly Department of Civil Structural and Environmental EngineeringUniversity at Buffalo(SUNY)135 Ketter HallBuffalo NY 14260United States

Lifelines are critical infrastructure systems characterized by a high level of interdependency that can lead to cascading failures after any *** approaches can be used to analyze infrastructural interdependencies,but they are usually not able to describe the sequence of events during ***,interdependencies need to be modeled also taking into account the time *** methodology proposed in this paper is based on a modified version of the Input-output Inoperability Model and returns the probabilities of failure for each node of the *** are modeled using graph theory,while perturbations,representing a natural or man-made disaster,are applied to the elements of the network following predetermined *** cascading effects among interdependent networks have been simulated using a spatial multilayer approach,while the use of an adjacency tensor allows to consider the temporal dimension and its *** method has been tested on a case study based on the 2011 Fukushima Dai-ichi nuclear *** configurations of the system have been analyzed and their probability of occurrence *** models of the nuclear power plant have been developed to evaluate how different spatial scales and levels of detail affect the results.

关键词： Interdependent infrastructure Nuclear power plant Cascading effects Temporal networks Input-output methods

Ageing and reliability of electrical insulation: the risk of hybrid AC/DC grids

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High Voltage 2020年第5期5卷 620-627页

作者： gian Carlo Montanari Peter Morshuis paolo Seri Riddhi Ghosh CAPS Florida State UniversityTallahasseeUSA School of Electrical Engineering Xi'an Jiaotong UniversityXi'anPeople's Republic of China University of Bologna BolognaItaly

With an impetuous growth of DC links and future grids that will be often hybrid,providing AC and DC supply to nearby or the same customer,an important element is often neglected,that is,electrical *** are no doubts that overhead lines will step back compared to insulated cables,for known reasons of environmental impact,right of way and reliability,especially in an urban or harsh *** the other hand,while AC insulation systems have been investigated and used for decades,there is no analogue experience for DC polymeric insulation,nor for insulation systems subjected to power electronics *** study aims at enhancing the attention on this topic,focusing on insulation ageing mechanisms and models of relevance for hybrid AC/DC assets and *** and life models for AC,DC and power electronics supply are discussed and compared to experimental data,focusing on partial discharge and space *** is shown how these two phenomena affect lifetime for different AC,DC and transient operating *** main drivers for insulation design and material selection are discussed,showing that insulation reliability can be achieved only if operating stresses,ageing mechanisms and life models are known and accounted for properly by insulation designers.

关键词： insulation electrical properly

A first order evaluation of the capacity of a healthcare network under emergency

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 663-677页

作者： gian paolo Cimellaro Sebastiano Marasco Ali Zamani Noori Stephen A. Mahin Department of Civil and Environmental Engineering University of California Berkeley CA 94720-1710 USA Department of Civil Structural & Geotechnical Engineering Politecnico di Torino Turin 10129 Italy

Immediately after an earthquake a healthcare system within a city, comprising several hospitals, endures an extraordinary demand. This paper proposes a new methodology to estimate whether the hospital network has enough capacity to withstand the emergency caused by an earthquake. The ability of healthcare facilities and to provide a broad spectrum of emergency services immediately after a seismic event is assessed through a metamodel that assumes waiting time as main response parameter to assess the hospital network performance. The First Aid network of San Francisco subjected to a 7.2 Mw magnitude earthquake has been used as case study. The total number of injuries and their distributions among the six major San Francisco’s Emergency Departments have been assessed and compared with their capacity that has been determined using a survey conducted by the medical staff of the hospitals. The numerical results have shown that three of the six considered San Francisco’s hospitals cannot provide emergency services to the estimated injured. Two alternatives have been proposed to improve the performance of the network. The fi rst one redistributes existing resources while the second one considers additional resources by designing a new Emergency Department.

关键词： resilience hospital networks earthquake injured performance San Francisco

Reply to "Discussion 1 on 'Introspection on improper seismic retrofit of Basilica Santa Maria di Collemaggio after 2009 Italian earthquake' by ***,*** and *** Stefano" by Vincenzo Ciampi

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Earthquake Engineering and Engineering Vibration 2012年第2期11卷 283-288页

作者： gian paolo Cimellaro Andrei M.Reinhorn Alessandro De Stefano Department of Structural Geotechnical & Building Engineering(DISEG)Politecnico di TorinoCorso Duca degli Abruzzi 2410129 TurinItaly Department of Civil Structural & Environmental EngineeringUniversity at Buffalothe State University of New York135 Ketter HallBuffalo NYUSA

The authors thank the discusser for his interest and careful review of the paper and his valuable comments. They also welcome this discussion,because it gives the authors the opportunity to clarify several points whic... 详细信息

关键词： Introspection on improper seismic retrofit of Basilica Santa Maria di Collemaggio after 2009 Italian earthquake by Vincenzo Ciampi Discussion 1 on Reply to De