Validity and Reliability of the Greek Version of the Multiple Sclerosis International Quality-of-Life Questionnaire

Nikos Triantafyllou,Aris Triantafillou,Georgios Tsivgoulis 대한신경과학회 2009 Journal of Clinical Neurology Vol.5 No.4

Background and Purpose There are no data regarding psychometrically validated, healthrelated quality-of-life instruments designed specifically for patients with multiple sclerosis (MS) in Greece. Recently, the MS International Quality-of-Life questionnaire (MusiQoL), a multidimensional, self-administered questionnaire, which is available in 14 languages (including Greek), has been validated using a large international sample. We investigated the validity and reliability of the Greek version of the MusiQoL. Methods Consecutive patients with different types and severities of MS were recruited from two tertiary-care centers in Greece. All patients completed the MusiQoL, the Short-Form-36 quality-of-life questionnaire (SF-36), and a symptom checklist at baseline and 21±7 days (mean± SD) later. Data regarding sociodemographic status, MS history, and functional outcome were also collected prospectively. Construct validity, internal consistency, reproducibility, and external consistency were tested. Results A total of 92 patients was evaluated. The construct validity was confirmed in terms of satisfactory item-internal consistency correlations and scaling success (87.5-100%) of itemdiscriminant validity. The dimensions of the MusiQoL exhibited high internal consistency (Cronbach’s alpha: 0.63-0.96), and reproducibility was satisfactory (intraclass correlation coefficients: 0.69-0.99). External validity testing indicated that the MusiQoL correlated significantly with all SF-36 dimension scores (Spearman’s correlation: 0.43-0.76). Conclusions The Greek version of the MusiQoL appears to be a valid and reliable instrument for measuring quality of life in Greek MS patients.

Simulation of PZT monitoring of reinforced concrete beams retrofitted with CFRP

Providakis, C.P.,Triantafillou, T.C.,Karabalis, D.,Papanicolaou, A.,Stefanaki, K.,Tsantilis, A.,Tzoura, E. Techno-Press 2014 Smart Structures and Systems, An International Jou Vol.14 No.5

A numerical study has been carried out to simulate an innovative monitoring procedure to detect and localize damage in reinforced concrete beams retrofitted with carbon fiber reinforced polymer (CFRP) unidirectional laminates. The main novelty of the present simulation is its ability to conduct the electromechanical admittance monitoring technique by considerably compressing the amount of data required for damage detection and localization. A FEM simulation of electromechanical admittance-based sensing technique was employed by applying lead zirconate titanate (PZT) transducers to acquire impedance spectrum signatures. Response surface methodology (RSM) is finally adopted as a tool for solving inverse problems to estimate the location and size of damaged areas from the relationship between damage and electromechanical admittance changes computed at PZT transducer surfaces. This statistical metamodel technique allows polynomial models to be produced without requiring complicated modeling or numerous data sets after the generation of damage, leading to considerably lower cost of creating diagnostic database. Finally, a numerical example is carried out regarding a steel-reinforced concrete (RC) beam model monotonically loaded up to its failure which is also retrofitted by a CFRP laminate to verify the validity of the present metamodeling monitoring technique. The load-carrying capacity of concrete is predicted in the present paper by utilizing an Ottosen-type failure surface in order to better take into account the passive confinement behavior of retrofitted concrete material under the application of FRP laminate.

Damage detection of reinforced concrete columns retrofitted with FRP jackets by using PZT sensors

Tzoura, Efi A.,Triantafillou, Thanasis C.,Providakis, Costas,Tsantilis, Aristomenis,Papanicolaou, Corina G.,Karabalis, Dimitris L. Techno-Press 2015 Structural monitoring and maintenance Vol.2 No.2

In this paper lead zirconate titanate transducers (PZT) are employed for damage detection of four reinforced concrete (RC) column specimens retrofitted with carbon fiber reinforced polymer (CFRP) jackets. A major disadvantage of FRP jacketing in RC members is the inability to inspect visually if the concrete substrate is damaged and in such case to estimate the extent of damage. The parameter measured during uniaxial compression tests at random times for known strain values is the real part of the complex number of the Electromechanical Admittance (Conductance) of the sensors, obtained by a PXI platform. The transducers are placed in specific positions along the height of the columns for detecting the damage in different positions and carrying out conclusions for the variation of the Conductance in relation to the position the failure occurred. The quantification of the damage at the concrete substrate is achieved with the use of the root-mean-square-deviation (RMSD) index, which is evaluated for the corresponding strain values. The experimental results provide evidence that PZT transducers are sensitive to damage detection from an early stage of the experiment and that the use of PZT sensors for monitoring and detecting the damage of FRP-retrofitted reinforced concrete members, by using the Electromechanical Admittance (EMA) approach, can be a highly promising method.

WHAT'S IN A NAME? GRASPING NEW PUBLIC GOVERNANCE AS A POLITICALADMINISTRATIVE SYSTEM

JACOB TORFING,PETER TRIANTAFILLOU 한국행정학회 2013 International Review of Public Administration Vol.18 No.2

New participatory, interactive, and less direct forms of governing seem currently to be unfolding in many liberal democracies. Some scholars have tried to conceptualize these forms of governing by using the notion of new public governance (NPG). While promising, the notion remains conceptually underdeveloped. This article first aims to develop NPG from an empirical to an analytical concept that enables categorization and evaluation of new forms of governing. In order to gauge the full scope of the current transformations we draw on David Easton’s system theoretical model to identify the constitutive elements of NPG and show how they differ from those elements underpinning classical public administration and new public management. The second aim of the article is to delineate the main challenges that NPG poses for public management and policymaking in a complex and fragmented world. We conclude by reflecting on the need for metagovernance in order to handle the challenges and bring out the positive impact of NPG on normative performance goals such as efficiency, democracy, and innovation.

Simulation of PZT monitoring of reinforced concrete beams retrofitted with CFRP

C.P. Providakis,K. Stefanaki,T.C. Triantafillou,D. Karabalis,A. Papanicolaou,A. Tsantilis,E. Tzoura 국제구조공학회 2014 Smart Structures and Systems, An International Jou Vol.14 No.5

A numerical study has been carried out to simulate an innovative monitoring procedure to detect and localize damage in reinforced concrete beams retrofitted with carbon fiber reinforced polymer (CFRP) unidirectional laminates. The main novelty of the present simulation is its ability to conduct the electro-mechanical admittance monitoring technique by considerably compressing the amount of data required for damage detection and localization. A FEM simulation of electromechanical admittance-based sensing technique was employed by applying lead zirconate titanate (PZT) transducers to acquire impedance spectrum signatures. Response surface methodology (RSM) is finally adopted as a tool for solving inverse problems to estimate the location and size of damaged areas from the relationship between damage and electro-mechanical admittance changes computed at PZT transducer surfaces. This statistical metamodel technique allows polynomial models to be produced without requiring complicated modeling or numerous data sets after the generation of damage, leading to considerably lower cost of creating diagnostic database. Finally, a numerical example is carried out regarding a steel-reinforced concrete (RC) beam model monotonically loaded up to its failure which is also retrofitted by a CFRP laminate to verify the validity of the present metamodeling monitoring technique. The load-carrying capacity of concrete is predicted in the present paper by utilizing an Ottosen-type failure surface in order to better take into account the passive confinement behavior of retrofitted concrete material under the application of FRP laminate.

Dietary Supplementation of Benzoic Acid and Essential Oil Compounds Affects Buffering Capacity of the Feeds, Performance of Turkey Poults and Their Antioxidant Status, pH in the Digestive Tract, Intestinal Microbiota and Morphology

Giannenas, I.,Papaneophytou, C.P.,Tsalie, E.,Pappas, I.,Triantafillou, E.,Tontis, D.,Kontopidis, G.A. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.2

Three trials were conducted to evaluate the effect of supplementation of a basal diet with benzoic acid or thymol or a mixture of essential oil blends (MEO) or a combination of benzoic acid with MEO (BMEO) on growth performance of turkey poults. Control groups were fed a basal diet. In trial 1, benzoic acid was supplied at levels of 300 and 1,000 mg/kg. In trial 2, thymol or the MEO were supplied at levels of 30 mg/kg. In trial 3, the combination of benzoic acid with MEO was evaluated. Benzoic acid, MEO and BMEO improved performance, increased lactic acid bacteria populations and decreased coliform bacteria in the caeca. Thymol, MEO and BMEO improved antioxidant status of turkeys. Benzoic acid and BMEO reduced the buffering capacity compared to control feed and the pH values of the caecal content. Benzoic acid and EOs may be suggested as an effective alternative to AGP in turkeys.