Numerical and Experimental Investigation of Residual Stress and Bond Strength in Friction Surface Cladding Process

The bond strength is an essential property of cladded products, which are produced by deposition processes such as friction surface cladding (FSC). Friction and severe plastic deformation of the deposited material cause the process to take place at elevated temperatures, and inhomogeneous cooling after the deposition process can lead to the formation of residual stresses that influence the remaining bond strength. A novel simulation method for the evaluation of the residual stress distribution in clad layer and substrate after the cladding of AA6060 onto an AA2024 substrate is proposed in this study. The effect of residual stresses on the bond strength was correlated with data gathered from 3-point bending tests aimed at the determination of the mechanical properties at the clad layer–substrate interface. The results show that on the one side, the occurrence of a higher compressive residual stress magnitude increases the bond strength, but on the other side, this relationship is not always true for average tool temperature, tool rotating speed, normal force, and tool tilt angle. Therefore, it is necessary to investigate the effect of average tool temperature, tool rotating speed, normal force, and tool tilt angle parameters on the residual stress to find the best process window for carrying out the process to have optimal bond strength.</p

Diversity of virulence factors associated with West Australian methicillin-sensitive staphylococcus aureus isolates of human origin

An extensive array of virulence factors associated with S. aureus has contributed significantly to its success as a major nosocomial pathogen in hospitals and community causing variety of infections in affected patients. Virulence factors include immune evading capsular polysaccharides, poly-N-acetyl glucosamine, and teichoic acid in addition to damaging toxins including hemolytic toxins, enterotoxins, cytotoxins, exfoliative toxin, and microbial surface components recognizing adhesive matrix molecules (MSCRAMM). In this investigation, 31 West Australian S. aureus isolates of human origin and 6 controls were analyzed for relative distribution of virulence-associated genes using PCR and/or an immunoassay kit and MSCRAMM by PCR-based typing. Genes encoding MSCRAMM, namely, Spa, ClfA, ClfB, SdrE, SdrD, IsdA, and IsdB, were detected in >90% of isolates. Gene encoding a-toxin was detected in >90% isolates whereas genes encoding ß-toxin and SEG were detectable in 50-60% of isolates. Genes encoding toxin proteins, namely, SEA, SEB, SEC, SED, SEE, SEH, SEI, SEJ, TSST, PVL, ETA, and ETB, were detectable in >50% of isolates. Use of RAPD-PCR for determining the virulence factor-based genetic relatedness among the isolates revealed five cluster groups confirming genetic diversity among the MSSA isolates, with the greatest majority of the clinical S. aureus (84%) isolates clustering in group IIIa

Correlation of clinical signs and symptoms of Behçet�s disease with mean platelet volume (MPV) and red cell distribution width (RDW)

Background: A strong correlation was previously found between mean platelet volume (MPV), red blood cell distribution width (RDW), and the severity of signs and symptoms in patients suffering from inflammatory and autoimmune diseases. The current study evaluated these correlations in patients with Behçet�s disease (BD) as well the relationship between MPV and RDW and disease activity score on the Iranian Behçet�s Disease Dynamic Activity Measurement (IBDDAM). Methods: This cross-sectional study included 319 patients with BD for whom demographic and epidemiological data, IBDDAM scores, and duration of illness was recorded. Blood samples were then obtained and the relationships between their disease status and manifestations and their laboratory parameters were evaluated with statistical models to find possible correlations. Results: Our analysis showed a significantly higher RDW in patients with BD who had ocular manifestations (p < 0.001) and oral aphthae (p = 0.004). Patients with active BD had higher RDW (p < 0.001) and MPV (p < 0.001) in comparison to those with currently inactive BD. Similarly, patients who had any type of ocular manifestation had higher RDW (p < 0.001) and MPV (p < 0.001). Regression analyses identified a statistically significant model for the effect of RDW and MPV in predicting active BD status (p < 0.001), as well as its significant relationship with active ocular manifestations (p < 0.001). Conclusion: BD was found to be associated with an increase in MPV and RDW, particularly during active phases. RDW and MPV were also found to have predictive value for screening to detect BD activity and its ocular complications. © 2020, The Author(s)

Knowledge, attitude and practice of nuclear medicine staff towards radiation protection

Introduction: Ionizing radiation in medical imaging is one of the dominant sources of exposure, and correct knowledge of radiation protection, affects staff safety behaviors during procedures. This study aimed to assess the radiation protection Knowledge, Attitude and Practice (KAP) amongst nuclear medicine centers' staff in Iran. Methods: To evaluate the level of radiation protection KAP, a validated questionnaire was distributed between 243 participants considering demographic characteristics in different geographical regions in Iran from 2014 to 2015. Results: There were statistically significant differences in the level of nuclear medicine staff KAP radiation protection with gender (p0.05). Conclusion: Our findings have shown that radiation protection KAP level of nuclear medicine staff was inadequate in some regions. This might be due to the lack of continuous training and absence of adequate safety knowledge about ionizing radiation. It seems that awareness about radiation protection rules and regulations, along with continuous training and preparations has a direct effect on radiation practice leading to enhanced KAP of staff in nuclear medicine centers. © 2019 Tehran University of Medical Sciences. All rights reserved

Radiation protection knowledge, attitude, and practice (KAP) in interventional radiology

Objectives: Due to increasing cardiac disease and its mortality rate, the frequency of cardiac imaging has grown and, as a result, interventional cardiologists potentially receive high radiation doses in cardiac examinations. This study aimed to assess the knowledge, attitude, and practice (KAP) level of radiation protection (RP) among interventional radiology staff in Iranian health care centers across the country. Methods: We used a validated questionnaire survey consisting of 30 multiple-choice questions to perform a cross-sectional study. Participants were healthcare personnel working professionally with radiation at different levels (i.e., secretary, radiology technologists, nurse, and physician). The questionnaire was divided into three sections to assess KAP regarding RP. Results: Significant differences exist in RP KAP mean scores based on educational age (p 0.050). We found a significant difference between RP KAP mean scores and different regions (p < 0.050). Conclusions: Educational and practice age, sex, type of hospital, and geographical region affect he KAP of interventional radiology staff regarding RP. Since many of the subjective radiation harms for both medical team and patients, this can be easily controlled and prevented; a checkup for personnel of interventional radiology departments, considering samples from different parts of the country with different levels of education, continuous training, and practical courses may help map the status of KAP. The results of this study may also help authorized health physics officers design strategic plans to enhance the quality of such services in radiation departments. © 2018, Oman Medical Specialty Board. All rights reserved

Assessment of knowledge, attitude and practice of operating room personnelss in selected hospitals of Iran about radiation protection

Introduction: Radiation protection in hospitals is a very important topic due to some economical, health, human and moral considerations. In order to promote a radiological protection program in hospitals, it is very important to have a good knowledge and attitude, as well as proper practice of personnels in this area. Therefore, the purpose of this study was to investigate the current status regarding knowledge, attitude and practice of operating room personnels about radiation protection in Iran. Materials and Methods: This descriptive cross-sectional study was performed on 332 operating room personnels with multi-stage selection in hospitals on the knowledge, attitude and practice at different cities in Iran. To do so, the operating room staff was considered as a statistical society during 2015-2016. The respondents to the questionnaire included physicists, nurses, apprentice and secretaries in different hospitals with low, medium and large number of beds. The selected provinces included: Alborz, East Azarbaijan, Tehran, Khorasan Razavi, Semnan, Qom, Golestan, Gilan, Kurdistan, Kermanshah and Mazandaran. Data were analyzed using SPSS software version 16 and one-way ANOVA test (P<0.05). Results: The findings of this study indicate that there is a significant relationship between the level of knowledge, attitude and practice of operating room personnels in radiation protection and different provinces. Also, the number of hospital beds is related whit the level of knowledge, attitude and performance of the personnels. Conclusion: The findings of current study showed that the provinces of Golestan, West Azarbayjan and Gilan had the highest level of knowledge, attitude and practice, respectively. Semnan, Tehran and Kurdistan were the provinces with the lowest level of knowledge, attitude and practice, respectively. There were also significant differences between the level of knowledge, attitude and practice of the personnel�s operating room with radiation protection and the place of service, which it can be due to the lack of supervision, facilities and lack of experience in deprived provinces, and oversight and inattention to the radiation exposure due to overcrowding of the services in non-deprived provinces. © 2018, Semnan University of Medical Sciences. All rights reserved

Tide Gauge Benchmark Monitoring Working Group Technical Report 2022

editorial reviewedApplications of the Global Navigation Satellite Systems (GNSS) to Earth Sciences are numerous. The International GNSS Service (IGS), a voluntary federation of government agencies, universities and research institutions, combines GNSS resources and expertise to provide the highest–quality GNSS data, products, and services in order to support high–precision applications for GNSS–related research and engineering activities. This IGS Technical Report 2022 includes contributions from the IGS Governing Board, the Central Bureau, Analysis Centers, Data Centers, station and network operators, working groups, pilot projects, and others highlighting status and important activities, changes and results that took place and were achieved during 2022

A survey on the radiation protection status among radiology staff

Introduction: Radiation exposure during radiological examination is a health concern, of which radiology professionals should be cognizant. We sought to evaluate the radiation protection knowledge, attitudes, and practice (KAP) amongst radiology staff of hospitals across 10 provinces of Iran. Materials and Methods: For evaluating the level of radiation protection KAP, 553 radiology staff were enrolled. A 32-item questionnaire was designed to assess radiation protection KAP, the validity which was confirmed by members of the Medical Physics and Biostatistics departments. The questionnaire evaluated the respondents' knowledge, practice, and attitudes towards the basic principles of radiation protection, the necessity of using protective equipment, and their performance in the implementation of radiation protection recommendations. Results: We found no significant difference in the level of radiation protection KAP between male and female radiology staff and among those with different educational levels and ages (P > 0.05). However, there was a significant association between radiation protection KAP and working experience, hospital size, and hospital type (P 0.05). Conclusion: Our results showed that the level of radiation protection KAP among radiology staff is inadequate. This might be due to the lack of ongoing training courses concerning protection against ionizing radiation. Thus, sustained training of radiation protection principles can promote KAP among the staff of radiology departments, and in turn, reduce public dose from medical diagnostic modalities. © 2018, Mashhad University of Medical Sciences

Analysis of baseline parameters in the HALT polycystic kidney disease trials

HALT PKD consists of two ongoing randomized trials with the largest cohort of systematically studied patients with autosomal dominant polycystic kidney disease to date. Study A will compare combined treatment with an angiotensin-converting inhibitor and receptor blocker to inhibitor alone and standard compared with low blood pressure targets in 558 early-stage disease patients with an eGFR over 60ml/min per 1.73m2. Study B will compare inhibitor-blocker treatment to the inhibitor alone in 486 late-stage patients with eGFR 25–60ml/min per 1.73m2. We used correlation and multiple regression cross-sectional analyses to determine associations of baseline parameters with total kidney, liver, or liver cyst volumes measured by MRI in Study A and eGFR in both studies. Lower eGFR and higher natural log-transformed urine albumin excretion were independently associated with a larger natural log–transformed total kidney volume adjusted for height (ln(HtTKV)). Higher body surface area was independently associated with a higher ln(HtTKV) and lower eGFR. Men had larger height-adjusted total kidney volume and smaller liver cyst volumes than women. A weak correlation was found between the ln(HtTKV) and natural log–transformed total liver volume adjusted for height or natural log liver cyst volume in women only. Women had higher urine aldosterone excretion and lower plasma potassium. Thus, our analysis (1) confirms a strong association between renal volume and functional parameters, (2) shows that gender and other factors differentially affect the development of polycystic disease in the kidney and liver, and (3) suggests an association between anthropomorphic measures reflecting prenatal and/or postnatal growth and disease severity

A qualitative study of nursing student experiences of clinical practice

BACKGROUND: Nursing student's experiences of their clinical practice provide greater insight to develop an effective clinical teaching strategy in nursing education. The main objective of this study was to investigate student nurses' experience about their clinical practice. METHODS: Focus groups were used to obtain students' opinion and experiences about their clinical practice. 90 baccalaureate nursing students at Shiraz University of Medical Sciences (Faculty of Nursing and Midwifery) were selected randomly from two hundred students and were arranged in 9 groups of ten students. To analyze the data the method used to code and categories focus group data were adapted from approaches to qualitative data analysis. RESULTS: Four themes emerged from the focus group data. From the students' point of view," initial clinical anxiety", "theory-practice gap"," clinical supervision", professional role", were considered as important factors in clinical experience. CONCLUSION: The result of this study showed that nursing students were not satisfied with the clinical component of their education. They experienced anxiety as a result of feeling incompetent and lack of professional nursing skills and knowledge to take care of various patients in the clinical setting