MATLAB for All Steps of Dynamic Vibration Test of Structures

With the recent advances in computer technology and digital simulation software, it is now possible to rapidly and accurately build computer models for complex linear and nonlinear dynamic systems. MATLAB is a unique system that can be used for structural and earthquake engineering problems. This study presents MATLAB tools developed for numerical process of all steps of dynamic vibration test of structures. The functions of the tools are processing the signals obtained from forced and ambient vibration tests of structures, determining the dynamic characteristics of structural systems, and automatically updating the analytical finite element (FE) models. The software group is composed of three programs named as SignalCAD, ModalCAD, and FemUP. The SignalCAD program is developed for processing raw measured data obtained from forced and ambient vibration tests of engineering structures. The ModalCAD program is developed for dynamic characteristic identification and validation procedure. The peak picking method, complex exponential method, and polyreference time domain method are used for modal identification process. The FemUP program is developed for automatically updating the numerical models of structures compared to modal testing results. Each program has a unique graphical user interface and is designed as user friendly. The possibilities of the programs are demonstrated with the model vibration test of a steel cantilever beam. The obtained results are compared to the analytical model, and the FE model is automatically updated, whereas the experimental model is considered as the reference model. Finally, it is seen that MATLAB can be used as a scientific programming platform in all vibration test and modal analysis applications

Context, Process and Change: The Status of Prospective Teachers\u27 Perceptions of Teaching Process

Teacher candidates come to teacher education programs with beliefs shaped out of traditional contexts in their earlier lives. Those beliefs influence their new learning outcomes. It is therefore important for teacher education programs to identify the degree of perceptions that entry- and exit-level candidates hold. The purpose of this study is to identify and compare entry- and exit-level candidates’ degree of perceptions about teaching process and to understand if their perceptions relate to their personal variables. This is a descriptive study. The data were gathered by 28-item Teaching Process Perception Scale developed by the researchers. Collected from 267 teacher candidates in a primary level teacher education program, the data were analyzed by using frequencies, percentages, t-test, and ANOVA. Comparing the perceptions of both groups, the results indicate a significant difference on behalf of the last year candidates, though the difference is small. The variables of gender, high school education, mother-father’s education and mother-father’s job do not significantly relate to the perceptions of the participants. The last-year female participants, however, scored significantly higher than their male counterparts. The results propose a need for practitioners to invite experiences that best challenge perceptions

Neutrophil-lymphocyte ratio in catatonia

There is growing evidence of subclinical inflammation in mental disorders. Objective: The aim of this study was to investigate frequency of symptoms of catatonia and the newly diagnosed subclinical inflammatory markers which are neutrophil/lymphocyte (NLR), platelet/lymphocyte (PLR), monocyte/lymphocyte (MLR) ratios in catatonia patients due to mental disorders. Methods: Patients who were admitted to psychiatry clinic with the diagnosis of catatonia according to DSM 5 in the last two years and equal number of control group were included in this retrospective study. Univariate analysis of covariance controlled for possible confounders was used to compare NLR, PLR, MLR ratios between patients and the control group. Results: A total of 34 catatonia patients and 34 healthy controls were included in the study. Patients’ mean age was 30.88 + 13.4. NLR value was significantly higher in the patient group than control group. There was no significant difference between the patients and control group according to PLR, MLR values. Discussion: The presence of subclinical inflammation in catatonic syndrome due to mental disorders should be considered. Subclinical inflammation that was observed in numerous mental disorders continues in catatonia due to mental disorders. Large-scale studies are needed to determine the role of inflammation in catatonia

Student Centered Education Scale: A Validity and Reliability Study

The purpose of the study is to develop a valid and reliable scale to measure the teachers’ levels of student-centered education practices. The Exploratory Factor Analysis sample included a total of 426 teachers and the Confirmatory Factor Analysis of the scale was conducted on a total of 160 teachers working in the province of Duzce during the spring term of 2014-2015 education year. Exploratory Factor Analysis was performed to test the construct validity of the scale and the model was tested through the Confirmatory Factor Analysis. For the reliability, Cronbach’s Alpha internal coefficient was calculated and item analysis was performed based on the corrected item total correlation. The final form of the scale included 32 items and one dimension. These 32 items explained 40.04% of the total variance. The results of the item total correlation analysis indicated that none of the item was below 0.30 and the lowest item correlation coefficient was 0.51. Cronbach’s Alpha was found to be 0.95 for the internal consistency of the scale. The reliability and validity results for the Student-Centered Education Scale suggest that this scale is a reliable and valid tool to measure the levels of student-centered educational practices among teachers

Improved arterial stiffness in mitral stenosis after successful percutaneous balloon valvuloplasty

Background: Rheumatic mitral stenosis (MS) is still a common disease in developing countries with high morbidity and mortality rates. The purpose of the study was to evaluate arterial stiffness in severe MS before and after percutaneous mitral balloon valvuloplasty (PMBV). Methods: Thirty patients with MS in sinus rhythm requiring PMBV and 20 age-gender matched healthy volunteers. The analyze of pulse wave velocities (PWV) were performed using of the carotid artery at the femoral by PWV technique on patients at baseline and a week after PMBV. Results: The values of PWV were significantly decreased after successful PMBW in MS patients. Mitral mean gradients and systolic pulmonary artery pressures (sPAP) both on echocardiography and catheterization also had a significant decrease after PMBW. The mitral valve areas were significantly increased after PMBW. There was a highly significant negative correlation between mitral valve areas and PWV values. A highly significant positive correlation was seen between mitral mean gradient on catheterization and PWV (r = 0.830, p < 0.001). There was also a significant correlation between sPAP on catheterization and PWV values (r = 0.639, p < 0.001). Echocardiographic mitral mean gradients and PWV were highly positive correlated with each other (r = 0.841, p < 0.001). The sPAP on echocardiography had also a highly positive correlation with PWV (r = 0.681, p < 0.001). Conclusions: Mitral stenosis is a cause of impaired arterial stiffness and after the enlargened mitral valve area arterial stiffness improved in patients with MS

The frequency of microscopic and focal active colitis in patients with irritable bowel syndrome

<p>Abstract</p> <p>Background</p> <p>Irritable bowel syndrome (IBS) is a chronic functional bowel disorder. The frequency of microscopic colitis and focal active colitis in the colonic mucosa has been investigated in IBS patients.</p> <p>Methods</p> <p>Between June 2007 and September 2010, 378 patients (between 16 and 84 years) were recruited prospectively. Of these 378 patients, 226 patients were diagnosed with IBS using the Rome III criteria. 152 control patients were also enrolled who were undergoing colonoscopy for colorectal cancer screening or investigation of anemia. Histopathological abnormalities identified during colonoscopy were compared between the IBS and control groups.</p> <p>Results</p> <p>The average age of the IBS group was 46.13 ± 14.16 years and and the average age of the control group was 57.01 ± 13.07 years. The prevalence of microscopic colitis (MC) in the diarrhea predominant and the mixed subgroup of IBS patients was 4.32% (7/162) whereas in all IBS patients, the prevalence was 3.09% (7/226). MC was not found in the 152 control cases, (p = 0.045). Lymphocytic colitis was seen in 7 IBS patients, with 1 case in the mixed group and 6 cases in the diarrhea group and there was a significant difference in the frequency of lymphocytic colitis between the IBS subgroups (p < 0.01). Focal active colitis was found in 6.6% (15/226) of the IBS patients and in none of the controls (p < 0.01), and there was no differences between IBS subtypes.</p> <p>Conclusion</p> <p>Microscopic colitis was more often found in the diarrhea predominant/mixed subgroups of IBS patients and in patients who were older women. In patients who are older woman with non-constipated IBS, it may be reasonable to perform a biopsy to screen for microscopic colitis. Focal active colitis was significantly increased in patients with IBS compared to controls.</p