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In this paper, a flexible laser beam profiler is proposed to easily measure the profile of a train wheel for railway inspection. It only requires two laser beams (together and in parallel) to obtain two three-dimensional point-clouds based on the laser triangulation principle. Either the laser beam profiler or the wheel can be freely moved. The motion need not be known. The wheel profile will be obtained in two steps. First, the wheel axis position and orientation are obtained by minimizing the distance between one of the point-clouds and the other translated point-cloud, and translation is defined as a rotation of any point on the point-cloud around the wheel axis until it lies on the other point-cloud's laser plane. In the second step, the wheel profile is extracted by selecting one of the point-clouds and rotating it about the wheel axis and by finding the intersection of rotating points and a perpendicular plane, the perpendicular plane is defined as any arbitrary plane which passes through the wheel axis. This method is useful particularly for obtaining geometrical parameters of a wheel such as flange height, flange slope and flange thickness. In order to commission the proposed method, a prototype system was designed and manufactured. The performance of the system, evaluated in different circumstances, shows a measurement error of up to 2%. Compared with classical methods utilizing a caliper or those which use expensive equipment or additional parts such as reference guides, the proposed method is easy to use and flexible. Also, a novel calibration method is utilized to calibrate the system accurately and freely. [ABSTRACT FROM AUTHOR]

The effects of process atmosphere pO2, annealing time, and a minor Sn addition on the selective oxidation of a Fe-0.1C-2Mn-1.7Si (wt pct) advanced high-strength steel during continuous galvanizing heat treatments were determined. The reference and 0.05 wt pct Sn-added steels were intercritically annealed at 1113 K (840 °C) for annealing times between 60 and 600 seconds in a N2-5 vol pct H2 gas atmosphere, where the process atmosphere pO2 was controlled by varying the dew points at 223 K, 243 K, and 278 K (−50 °C, −30 °C and +5 °C). It was found that both the internal and external oxidation kinetics followed a parabolic rate law and were significantly reduced by the Sn addition to the alloy. For the lowest pO2 223 K (−50 °C) dew point atmosphere, the external oxides comprised compact, film-like MnSiO3, SiO2, and granular MnO. The addition of Sn to the alloy reduced the compactness of the granular oxides. Increasing the atmosphere dew point to 243 K and 278 K (−30 °C and +5 °C) reduced the thickness of the external oxides and increased the depth of internal oxidation for both alloys. Under the highest pO2 278 K (+5 °C) dew point atmosphere, although the reference steel surface was covered with small, closely packed MnSiO3 nodule-like particles, the addition of Sn altered their morphology to larger, more widely spaced nodules and decreased the depth of internal oxidation. The effect of Sn was found to be the result of its segregation at the surface oxide/substrate interface, as shown by 3D atom probe tomography. The alterations in oxide morphology resulting from the Sn addition are expected to enhance the reactive wetting of the substrate surfaces by the continuous galvanizing bath. [ABSTRACT FROM AUTHOR]

Background: This study aimed to determine the prevalence of serum IgG and IgM antibodies against cytomegalovirus (CMV), rubella and herpes simplex virus (HSV) in the women with spontaneous abortion compared to women with normal delivery. Materials and Methods: This case-control study was performed on 81 women with spontaneous abortion (case) and 98 women with normal delivery (control) referred to the obstetrics and gynecology clinics of Tehran hospitals in 2013. All the serum samples were tested for CMV, HSV and rubella IgM and IgG antibodies using ELISA kits. The data along with demographics and the gestational age of the mothers were recorded in the questionnaire and analyzed using SPSS. Results: The positive IgG antibodies against CMV were 87.7% (n=71) and 90.8% (n=89) in the case and control groups, respectively. Moreover, the positive IgM antibodies were 25.9% (n=21) and 12.2 %( n=12) in the case and control groups, respectively (P= 0.02). IgG antibodies against rubella in the case and control groups were 75.3% (n=61) and 86.7% (n=85), respectively. Also, IgM antibodies were 1.2% (n=1) and 2% (n=2), respectively (P=0.03). IgG antibody against herpes was 79% (n=64) and 85.7% (n=84) in the case and control groups, respectively; IgM was positive (3.1%) in only 3 cases. Conclusion: Results of the present study reveal that the IgM antibody against CMV in case group was significantly higher than the control group, which shows the role of CMV in the occurrence of abortion. [ABSTRACT FROM AUTHOR]

Background and Aim: It is known that personal behavior influences one's health. The present study was designed to investigate lifestyle of non-medical students of governmental and private (Azad) universities in Kashan, Iran and factors affecting it. Materials and Methods: A cross-sectional study was carried out on 520 non-medical students in Kashan, Iran, selected by convenience sampling, in academic year 2013-14. Data on demographic characteristics and health behaviors were collected using standard valid questionnaires, for the latter the questionnaire being the Pender's Health Promoting Lifestyle Profile II (HPLP II). The data were analyzed using the Kolmogorov-Smirnov test, followed by t-test, and U Mann-Whitney test to compare the means of the two populations. Results: The mean age of the students was 21.75 ± 2.5 years. Their overall health-promoting lifestyle score was of 2.43 (SD = 0.38). This score, as well as scores for the subcategories – nutritional behavior, spiritual development, physical activity, health responsibility, and stress management – were lower for the subjects with an experience of stressful events. Further analysis of the data showed that there were significant differences between boys and girls as regards physical activity (P = 0.000), between single and married students as regards nutritional status (P = 0.032), and between working and non-working students as regards spiritual development (P = 0.014). Conclusion: The findings indicate that experienced stressful events lay the ground for the adoption of risky behaviors in university students. Therefore, universities should design and implement programs aiming at improving lifestyle of the students and promoting their health. [ABSTRACT FROM AUTHOR]

Background: Uropathogenic Escherichia coli (UPEC) is one of the most important etiologic agent of urinary tract infection (UTI). UPEC strains have various types of virulence factors such as adhesins, toxins and iron uptake systems. Virulence genes are located on transmissible genetic elements and/or in particular locus on the chromosome called pathogenicity islands (PAI). The aim of this study was to investigate the prevalence of UPEC and the virulence factors among the UPEC isolates. Materials and Methods: Of 370 urine samples collected from hospitalized patients with UTI in Kashan Shahid-Beheshti hospital, a total of 150 E.coli strains were isolated between December 2012 and June 2013. Biochemical and standard microbiological techniques were used to identify the E.coli followed by screening for virulence genes using the polymerase chain reaction (PCR). Results: The prevalence of UTI infection was 40.5% and the frequency of UPEC virulence genes was traT (74%), aer (30.7%), PAI (61.4%), sfa (0%), pap ( 16.7%), cnf1 (0%), afa (0%) and hly ( 4.5 %). Conclusion: Our study showed that the traT, PAI and aer virulence genes were highly prevalent among the UPEC strains isolated from hospitalized patients in our region; therefore, these genes could be studied as targets for medical interventions. [ABSTRACT FROM AUTHOR]

Background: Streptococcus pneumoniae, as an important human pathogen, is a leading cause of serious infections (e.g., sepsis, pneumonia and meningitis). Nasopharyngeal colonization is often the first step in the development of pneumococcal infections. The aim of this study was to determine the prevalence of S. pneumoniae serotypes in the nasopharynx of students in Kashan and its related risk factors. Materials and Methods: This cross-sectional study was conducted on 1289 students in Kashan from November 2011 to December 2012. Demographic and clinical data were collected from patients using a questionnaire. Samples were cultured on a selective media. Moreover, S. pneumoniae strains were identified using gram staining, detecting alpha hemolysis, catalase, optochin susceptibility and bile solubility tests. Results: One-hundred eighty one out of 1289 (14%) students were carriers for nasopharyngeal S. pneumoniae. There was a significant correlation between sex, age, previous respiratory infections, asthma, runny nose and previous hospitalization with an increased rate of the pneumococcal carriers. Conclusion: According to the high prevalence of pneumococcal carriers and a significant correlation between increased rates of colonization and sex, age, previous respiratory infections, asthma, runny nose and previous hospitalization, applying preventive strategies such as student vaccination seems to be necessary. [ABSTRACT FROM AUTHOR]

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important pathogen in the hospital and community. Therefore, a precise identification of the antibiotic-resistant strains is essential to control the infection and prevent the MRSA transmission rates. The aim of this study was to determine a diagnostic value of cefoxitin susceptibility test compared with the oxacillin susceptibility test and E-test (Epsilometer test) for detection of MRSA. Materials and Methods: This study was conducted on 296 S.aureus isolated from the nasal specimen patients of referred to emergency department of Kashsn Shahid-Beheshti hospital. Resistance to methicillin was determined by oxacillin (1μg), and cefoxitin (30μg) disk diffusion methods based on CLSI guideline and according to no growth zone size and the minimum inhibitory antibiotic concentration by E-test. PCR assay was used as a gold standard for detecting mecA gene in MRSA isolates. Results: Thirty-two (10.8%), 28 (9.5%), 30 (10.1%), 26 (8.8%) out of 296 S.aureus were considered as MRSA strains using the oxacillin and cefoxitin disk diffusion methods, E-test and PCR, respectively. Sensitivity, specificity, positive and negative predictive values for the oxacillin diffusion method were 100% , 97.7% , 81.2% and 100%; for the cefoxitin disk diffusion method 96.2%, 98.8%, 89.3% and 99.6% and for E-test 100%, 98.5%, 86.7% and 100%, respectively. Conclusion: PCR assay is the best method for detecting MRSA; however, it is an expensive method. Phenotypic methods, especially the cefoxitin disk diffusion method, can be a good alternative to PCR for detection of MRSA. [ABSTRACT FROM AUTHOR]

Background: Fibrinolytic therapy of myocardial infarction (MI) should be started as soon as possible after the onset of symptoms. Since efforts to reduce pre-hospital delay have shown limited success in treatment, substantial emphasis should be placed on reducing in-hospital delay. This study aimed to evaluate the in-hospital delay for fibrinolytic therapy in Kashan Shahid-Beheshti hospital during 2007-2010. Materials and Methods: This cross-sectional study was performed on 300 patients with ST-elevated myocardial infarction. Exclusion criteria were the previous MIs, incomplete data regarding the time of hospital admission or fibrinolysis and patients who were referred to the hospital by physicians outside the hospital. Demographic data, the time of symptom onset, admission time and fibrinolysis were collected and then analyzed. Results: Two hundred and twenty-five (75.3%) out of 300 patients were male. Most patients (63.7%) were in the age range of greater than 55 years. The mean of in-hospital delay was 57 minutes. Sixty-three percent of patients experienced an unacceptable delay of greater than 30 minutes and only 37% of the patients experienced an acceptable delay of equal or less than 30 minutes. The mean of pre-hospital delay was 136 minutes. Half (53.7%) of the patients had a total delay of less than 3 hours. There was no association between the in-hospital mortality and total or in-hospital delay. Conclusion: The majority of patients (63%) had an optimal in-hospital delay and the mean door-to-needle time was about two times more than the optimal. Furthermore, identifying and modifying of the contributing factors in triage and emergency wards seem to be effective for decreasing in-hospital delay in reperfusion therapy. [ABSTRACT FROM AUTHOR]