A spectrum-driven damage Identification technique : application and validation through the numerical simulation of the Z24 Bridge

The present paper focuses on a damage identification method based on the use of the second order spectral properties of the nodal response processes. The explicit dependence on the frequency content of the outputs power spectral densities makes them suitable for damage detection and localization. The well-known case study of the Z24 Bridge in Switzerland is chosen to apply and further investigate this technique with the aim of validating its reliability. Numerical simulations of the dynamic response of the structure subjected to different types of excitation are carried out to assess the variability of the spectrum-driven method with respect to both type and position of the excitation sources. The simulated data obtained from random vibrations, impulse, ramp and shaking forces, allowed to build the power spectrum matrix from which the main eigenparameters of reference and damage scenarios are extracted. Afterwards, complex eigenvectors and real eigenvalues are properly weighed and combined and a damage index based on the difference between spectral modes is computed to pinpoint the damage. Finally, a group of vibration-based damage identification methods are selected from the literature to compare the results obtained and to evaluate the performance of the spectral index.

Design and validation of a biomechanical bioreactor for cartilage tissue culture

Specific tissues, such as cartilage undergo mechanical solicitation under their normal performance in human body. In this sense, it seems necessary that proper tissue engineering strategies of these tissues should incorporate mechanical solicitations during cell culture, in order to properly evaluate the influence of the mechanical stimulus. This work reports on a user-friendly bioreactor suitable for applying controlled mechanical stimulation - amplitude and frequency - to three dimensional scaffolds. Its design and main components are described, as well as its operation characteristics. The modular design allows easy cleaning and operating under laminar hood. Different protocols for the sterilization of the hermetic enclosure are tested and ensure lack of observable contaminations, complying with the requirements to be used for cell culture. The cell viability study was performed with KUM5 cells.

Validation of a method to measure light distortion surrounding a source of glare

Our objective was to validate a new device dedicated to measure the light disturbances surrounding bright sources of light under different sources of potential variability. Twenty subjects were involved in the study. Light distortion was measured using an experimental prototype (light distortion analyzer, CEORLab, University of Minho, Portugal) comprising twenty-four LED arrays panel at 2 m. Sources of variability included: intrasession and intersession repeated measures, pupil size (3 versus 6 mm), defocus (þ0.50) correction for the working distance, angular resolution (15 deg versus 30 deg), temporal stimuli presentation, and pupil size. Size, shape, location, and irregularity parameters have been obtained. At a low speed of presentation of the stimuli, changes in angular resolution did not have an effect on the results of the parameters measured. Results did not change with pupil size. Intensity of the central glare source significantly influenced the outcomes. Examination time was reduced by 30% when a 30 deg angular resolution was explored instead of 15 deg. Measurements were fast and repeatable under the same experimental conditions. Size and shape parameters showed the highest consistency, whereas location and irregularity parameters showed lower consistency. The system was sensitive to changes in the intensity of the central glare source but not to pupil changes in this sample of healthy subjects.

Implementation and validation of a strain rate dependent anisotropic continuum model for masonry

A newly developed strain rate dependent anisotropic continuum model is proposed for impact and blast applications in masonry. The present model adopted the usual approach of considering different yield criteria in tension and compression. The analysis of unreinforced block work masonry walls subjected to impact is carried out to validate the capability of the model. Comparison of the numerical predictions and test data revealed good agreement. Next, a parametric study is conducted to evaluate the influence of the tensile strengths along the three orthogonal directions and of the wall thickness on the global behavior of masonry walls.

Convergent validation study of the Contemplation Ladder for application via telephone in tobacco users

OBJECTIVE: This work was designed to validate the Portuguese version of the Contemplation Ladder, whose purpose is to assess the motivational phase to quit smoking among tobacco users using a telephone service. METHOD: A cross-sectional study was conducted in a nationwide drug use information hotline. In order to assess the convergent validation, the correlation between the Contemplation Ladder and the URICA Scale was calculated, which was previously validated. RESULTS: The study included 271 tobacco users. Statistically significant correlations were found between the Contemplation Ladder scores and the scores of the URICA precontemplation (r=-0.16; p<0.01), action (r=0.15; p<0.01) and maintenance (r=0.18; p<0.01) subscales. The correlation between the URICA Scale compound score and the Contemplation Ladder was also significant (r=0.31; p<0.01). CONCLUSION: The results of our study suggest that the Contemplation Ladder can be an efficient substitute for the URICA scale (whose application lasts at least 20 minutes), without submitting the interviewee to a heavy load of questions. The study presented evidences of convergent validity for the Contemplation Ladder when applied via telephone in tobacco users.

Validation of the Portuguese version of the Evidence-Based Practice Questionnaire

OBJECTIVES: To describe the process of translation and linguistic and cultural validation of the Evidence Based Practice Questionnaire for the Portuguese context: Questionário de Eficácia Clínica e Prática Baseada em Evidências (QECPBE). METHOD: A methodological and cross-sectional study was developed. The translation and back translation was performed according to traditional standards. Principal Components Analysis with orthogonal rotation according to the Varimax method was used to verify the QECPBE's psychometric characteristics, followed by confirmatory factor analysis. Internal consistency was determined by Cronbach's alpha. Data were collected between December 2013 and February 2014. RESULTS: 358 nurses delivering care in a hospital facility in North of Portugal participated in the study. QECPBE contains 20 items and three subscales: Practice (α=0.74); Attitudes (α=0.75); Knowledge/Skills and Competencies (α=0.95), presenting an overall internal consistency of α=0.74. The tested model explained 55.86% of the variance and presented good fit: χ2(167)=520.009; p = 0.0001; χ2df=3.114; CFI=0.908; GFI=0.865; PCFI=0.798; PGFI=0.678; RMSEA=0.077 (CI90%=0.07-0.08). CONCLUSION: confirmatory factor analysis revealed the questionnaire is valid and appropriate to be used in the studied context.

Embedding, evolution, and validation of model-driven spreadsheets

This paper proposes and validates a model-driven software engineering technique for spreadsheets. The technique that we envision builds on the embedding of spreadsheet models under a widely used spreadsheet system. This means that we enable the creation and evolution of spreadsheet models under a spreadsheet system. More precisely, we embed ClassSheets, a visual language with a syntax similar to the one offered by common spreadsheets, that was created with the aim of specifying spreadsheets. Our embedding allows models and their conforming instances to be developed under the same environment. In practice, this convenient environment enhances evolution steps at the model level while the corresponding instance is automatically co-evolved.Finally,wehave designed and conducted an empirical study with human users in order to assess our technique in production environments. The results of this study are promising and suggest that productivity gains are realizable under our model-driven spreadsheet development setting.

Global validation of the WSES Sepsis Severity Score for patients with complicated intra-abdominal infections: a prospective multicentre study (WISS Study).

BACKGROUND To validate a new practical Sepsis Severity Score for patients with complicated intra-abdominal infections (cIAIs) including the clinical conditions at the admission (severe sepsis/septic shock), the origin of the cIAIs, the delay in source control, the setting of acquisition and any risk factors such as age and immunosuppression. METHODS The WISS study (WSES cIAIs Score Study) is a multicenter observational study underwent in 132 medical institutions worldwide during a four-month study period (October 2014-February 2015). Four thousand five hundred thirty-three patients with a mean age of 51.2 years (range 18-99) were enrolled in the WISS study. RESULTS Univariate analysis has shown that all factors that were previously included in the WSES Sepsis Severity Score were highly statistically significant between those who died and those who survived (p < 0.0001). The multivariate logistic regression model was highly significant (p < 0.0001, R2 = 0.54) and showed that all these factors were independent in predicting mortality of sepsis. Receiver Operator Curve has shown that the WSES Severity Sepsis Score had an excellent prediction for mortality. A score above 5.5 was the best predictor of mortality having a sensitivity of 89.2 %, a specificity of 83.5 % and a positive likelihood ratio of 5.4. CONCLUSIONS WSES Sepsis Severity Score for patients with complicated Intra-abdominal infections can be used on global level. It has shown high sensitivity, specificity, and likelihood ratio that may help us in making clinical decisions.

Validation of the Portuguese Version of EHP-30 (The Endometriosis Health Profile-30)

Introduction: Endometriosis Health Profile Questionnaire-30 is currently the most used questionnaire for quality of life measurement in women with endometriosis. The aim of this study is to evaluate the psychometric properties and to validate the Portuguese Endometriosis Health Profile Questionnaire-30 version. MATERIAL AND METHODS A sequential sample of 152 patients with endometriosis, followed in a Portugal reference center, were asked to complete a questionnaire on social and demographic features, the Portuguese version of the Endometriosis Health Profile Questionnaire-30 and of the Short Form Health Survey 36 Item â version 2. Appropriate statistical analysis was performed using descriptive statistics, factor analysis, internal consistency, item-total correlation and convergent validity. RESULTS Factorial analysis confirmed the validity of the five-dimension structure of the Endometriosis Health Profile Questionnaire-30 core questionnaire, which explained 83.2% of the total variance. All item-total correlations presented acceptable results and high internal consistency, with Cronbach's alpha ranging between 0.876 and 0.981 for the core questionnaire and between 0.863 and 0.951 for the modular questionnaire. Significant negative associations between similar scales of Endometriosis Health Profile Questionnaire-30 and Short Form Health Survey 36 Item â version 2 were demonstrated. Data completeness achieved was high for all dimensions. The emotional well-being scale in the core questionnaire and the infertility scale in the modular section had the highest median scores, and therefore the most negative impact on the quality of life of participating women. DISCUSSION The test-retest reliability and responsiveness of the questionnaire should be evaluated in future studies. CONCLUSION The present study demonstrates that the Portuguese version of the Endometriosis Health Profile Questionnaire-30 is a valid, reliable and acceptable tool for evaluating the health-related quality of life of Portuguese women with endometriosis.

Validation of the Disordered Eating Attitude Scale for adolescents

ABSTRACT Objective To perform the psychometric evaluation of the Disordered Eating Attitude Scale (DEAS) for adolescents. Methods Sample consisted of 1,119 Brazilian adolescents (12-18 years old; 59.6% female) studying at technical schools in São Paulo state-Brazil, who answered an online survey with the DEAS, the Eating Attitude Test (EAT-26), and the Restraint Scale (RS). The internal consistency of the DEAS was assessed using Cronbach’s alpha. The convergent validity of DEAS was evaluated by means of Pearson’s coefficient correlation with EAT-26 and RS. The test-retest reliability was evaluated using a sub-sample of 61 adolescents. Known-groups validity was determined by comparing female student mean scores with scores of 33 female adolescents with eating disorders. Results The reliability of the DEAS was 0.79. EAT-26 and RS scores were positively correlated with DEAS scores (EAT: 0.78 for females and 0.59 for males, p < 0.001; RS: 0.63 for females and 0.48 for males, p < 0.001). The DEAS total and subscale scores differentiated students and patients with eating disorders (p < 0.001). The intra-class correlation coefficient for test-retest reliability was 0.87. Conclusion Results indicate that the DEAS adolescent version showed good internal consistency, convergent validity, known-groups validity, and test-retest reliability, suggesting its potential in identifying disordered eating attitudes among adolescents. It could also be helpful in identifying adolescents at risk from eating disorders, assisting in prevention programs.

Percursos profissionais na área do emprego e educação e formação de adultos: estudo acerca do papel da orientação vocacional na gestão de carreiras na atualidade

Dissertação de mestrado em Sociologia (área de especialização em Desenvolvimento e Políticas Socias)

Validation study of an automated wrist monitor, omron model HEM-608, compared with the standard methods for blood pressure measurement

OBJECTIVE - The aim of our study was to assess the profile of a wrist monitor, the Omron Model HEM-608, compared with the indirect method for blood pressure measurement. METHODS - Our study population consisted of 100 subjects, 29 being normotensive and 71 being hypertensive. Participants had their blood pressure checked 8 times with alternate techniques, 4 by the indirect method and 4 with the Omron wrist monitor. The validation criteria used to test this device were based on the internationally recognized protocols. RESULTS - Our data showed that the Omron HEM-608 reached a classification B for systolic and A for diastolic blood pressure, according to the one protocol. The mean differences between blood pressure values obtained with each of the methods were -2.3 +7.9mmHg for systolic and 0.97+5.5mmHg for diastolic blood pressure. Therefore, we considered this type of device approved according to the criteria selected. CONCLUSION - Our study leads us to conclude that this wrist monitor is not only easy to use, but also produces results very similar to those obtained by the standard indirect method.

Study of validation of the Portuguese version of the inventory «Experiences in Close Relationships»

The Experiences in Close Relationships Inventory permits to evaluate attachment in close relationships during adulthood based on two dimensions able to be present in this kind of relationships: the avoidance of proximity and the anxiety related with to abandonment. It is a self-report 7- points likert scale composed by 36 items. The Portuguese version was administered to a sample of 551 university students (60% female), the majority with ages between 19 and 24 years old (88%) in a dating relationship (86%). The principal components analysis with oblimin rotation was performed. The total scale has good internal consistency (α=.86), as also has the 2 sub-scales: anxiety (α=.86) and avoidance (α=.88). The two dimensions evaluated are significantly correlated with socio-demographics, relational characteristics (jealousy, relationship distress, and compromise), wishes (enmeshment versus differentiation) and fears (abandonment versus control) related to attitudes in significant relationships, which testify the construct validity of the instrument. The results obtained are coherent with the original version and other ECR‘s adaptations. Practitioners and researchers in the context of clinical psychology and related areas have now at their disposal the Portuguese version of the ECR inventory, which has shown its very high usefulness in the study of close relationships, and specifically attachment in adulthood.

Experimental validation of a proposed single-phase five-level active rectifier operating with model predictive current control

This paper presents a model predictive current control applied to a proposed single-phase five-level active rectifier (FLAR). This current control strategy uses the discrete-time nature of the active rectifier to define its state in each sampling interval. Although the switching frequency is not constant, this current control strategy allows to follow the reference with low total harmonic distortion (THDF). The implementation of the active rectifier that was used to obtain the experimental results is described in detail along the paper, presenting the circuit topology, the principle of operation, the power theory, and the current control strategy. The experimental results confirm the robustness and good performance (with low current THDF and controlled output voltage) of the proposed single-phase FLAR operating with model predictive current control.

Assessment of the DIXTAL DX-2710 Automated Oscillometric Device for Blood Pressure Measurement with the Validation Protocols of the British Hypertension Society (BHS) and the Association for the Advancement of Medical Instrumentation (AAMI)

OBJECTIVE: To assess the Dixtal DX2710 automated oscillometric device used for blood pressure measurement according to the protocols of the BHS and the AAMI. METHODS: Three blood pressure measurements were taken in 94 patients (53 females 15 to 80 years). The measurements were taken randomly by 2 observers trained to measure blood pressure with a mercury column device connected with an automated device. The device was classified according to the protocols of the BHS and AAMI. RESULT: The mean of blood pressure levels obtained by the observers was 148±38/93±25 mmHg and that obtained with the device was 148±37/89±26 mmHg. Considering the differences between the measurements obtained by the observer and those obtained with the automated device according to the criteria of the BHS, the following classification was adopted: "A" for systolic pressure (69% of the differences < 5; 90% < 10; and 97% < 15 mmHg); and "B" for diastolic pressure (63% of the differences < 5; 83% < 10; and 93% < 15 mmHg). The mean and standard deviation of the differences were 0±6.27 mmHg for systolic pressure and 3.82±6.21 mmHg for diastolic pressure. CONCLUSION: The Dixtal DX2710 device was approved according to the international recommendations.