Application of Ultrasonic Guided Waves for Surface Roughness Measurement

Surface roughness is inherently a product of manufacturing process and is often undesirable. In surface metrology, the term “roughness” is typically applied to the highfrequency and short-wavelength parameters of a finished surface. In practical applications, the surface roughness is directly associated with the quality of the manufacturing. This study proposes the use of ultrasonic surface guided waves to characterize the surface roughness amplitude and frequency during the manufacturing process. Finite element modeling (FEM) of acoustic wave propagation along a rough surface has revealed that there is a cut-off threshold for Rayleigh wave propagation, which is indicative of the surface roughness description. This cut-off occurs for a particular ratio of the spatial surface waviness and the acoustic wavelength, and the detection of the resulting wave attenuation and decay characterizes the surface roughness. If such a measurement system can be used in-line with the production process then it could signal adjustment of the material deposition rate when needed to achieve the required product quality

Estimating utility value for female genital mutilation

Background: Female genital mutilation/cutting (FGM/C) is a clear violation of women's rights and can have adverse and irreversible health effects as well. Worldwide, more than 200 million women and girls have undergone FGM/C. Utility value of FGM/C has not been estimated yet, so we designed this study to extract the health utility value of FGM/C for the first time in the world. Methods: In a cross-sectional study in Iran, 125 girls and women who underwent FGM/C procedure were examined by the trained midwives in order to determine its type. In addition, a questionnaire was completed for identifying the socio-demographic factors and extracting the health utility of these individuals. Health utility was measured using Time Trade-off method and also to determine the effects of the socio-demographic factors on the health utility a two-limit censored regression model was applied. Results: The mean and median of the health utility of women with FGM/C were 0.971 (SE: 0.003) and 0.968 (IQR: 1-0.95), respectively. Number of non-Traders was 58 (46.4) who reported perfect health utility. However, the mean of health utility among traders was 0.946 (SE: 0.002). Only type 1 (Clitoridectomy) and type 2 (Excision) FGM/C were seen in this study. Women with Type 1 FGM/C had significantly lower health utility value (Mean: 0.968, Median: 0.957) than their type 2 counterparts (Mean: 0.987, Median: 1.00). Moreover, women in the age group of 31-45 years (Mean: 0.962, Median: 0.956), single (Mean: 0.950, Median: 0.954), divorced (Mean: 0.951, Median: 0.950), employed (Mean: 0.959, Median: 0.956), and with supplementary insurance (Mean: 0.962, Median: 0.950) had significantly lower health utility than their counterparts. Conclusion: FGM/C affects physical and psychological well-being of these individuals, resulting in a lack of personal and marital satisfaction, which ultimately leads to a 3 reduction in their health related quality of life. Therefore, preventing from this practice is very important and should be considered by health system policy makers more than before. © 2020 The Author(s)

Development of antimicrobial gelatin-ulvan-beeswax composite films: Optimization of formulation using mixture design methodology

A new generation of antimicrobial film was developed by incorporation of ulvan extracted from Ulva intestinalis into gelatin from common carp scale and its water sensitivity was reduced with addition of beeswax. Optimum composition of gelatin (0–100%w/w), ulvan (0–100%w/w) and beeswax (0–10%w/w) for achieving composite films with minimum water solubility (S) and water vapor permeability (WVP) and maximum tensile strength (TS), elongation at break point (EAB) and antibacterial effect on E. coli (EC) were investigated using mixture design methodology. Both pure gelatin and ulvan films and their composites had relatively good mechanical and optical properties. Addition of ulvan to gelatin produced composite films with good antibacterial properties but water resistance of all the films was weak. Addition of beeswax up to ∼5 % improved the water resistance and mechanical properties of the films without jeopardizing their antibacterial properties. The final optimum formulation with a desirability of 0.709 was achieved as 52.18 % of gelatin, 40.83 % of ulvan and 6.97 % of beeswax resulting in a minimum possible S (40 %) and WVP (1.86 10−10 g/ms Pa) and maximum possible TS (6.23 MPa) and EAB (89 %) with good EC (7.66 mm). Finally, good mechanical, thermal and microstructural properties of the optimum composite film was confirmed. Altogether, a combination of ulvan and beeswax can be a promising solution for development of gelatin films with both antimicrobial properties and lower water sensitivity

A comparative assessment of enamel mineral content and Streptococcus mutans population between conventional composites and composites containing nano amorphous calcium phosphate in fixed orthodontic patients: A split-mouth randomized clinical trial

Objectives: The aim of this 'split-mouth design' trial was to evaluate the effect of the nano amorphous calcium phosphate (NACP) containing composite on enamel mineral contents and streptococcus mutans population in fixed orthodontic patients. Design, setting, participants, and intervention: Randomized, prospective, single-center controlled trial. Twenty-four patients between the ages of 13-18 years participated in this study. The control and test sides were randomly selected by a coin toss (1:1 ratio). On the control side orthodontic brackets were bonded on the buccal surfaces of upper premolars and laterals using an orthodontic composite (Transbond XT), and on the study side NACP-containing composite was used. Outcome measures were the mineral content around the brackets and S.mutans count. The later were calculated in the plaque around the brackets by real-time PCR at 3 months, and 6 months after the initiation of treatment. All stages of the study were blind using coding system. Paired t-test and repeated measurements were used for data analysis. Results: In the third and sixth month, the bacterial population was significantly lower in the study side than the control side (P = 0.01 and 0.000).The mineral content of the study side was significantly higher than the controls, 6 months after brocket bonding (P = 0.004). There were no significant differences between the premolars and lateral teeth for all measurements. Limitations: This research was performed in a single-center by one experienced clinician. Conclusion: NACP-containing composites have the potential to inhibit mineral content loss and S.mutans colonization around orthodontic brackets during fixed orthodontic treatments. Trial registration: This trial was not registered. Protocol: The protocol was not published before trial commencement. © The Author 2016. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved

Enabling affordances of blockchain in agri-food supply chains: A value-driver framework using Q-methodology

The application of blockchain beyond cryptocurrencies has received increasing attention from industry and scholars alike. Given predicted looming food crises, some of the most impactful deployments of blockchains are likely to concern food supply chains. This study outlined how blockchain adoption can result in positive affordances in the food supply chain. Using Q- methodology, this study explored the current status of the agri-food supply chain and how blockchain technology could be useful in addressing existing challenges. This theorization leads to the proposition of the 3TIC value-driver framework for determining the enabling affordances of blockchain that would increase shared value for stakeholders. First, we propose a framework based on the most promising features of blockchain technology to overcome current challenges in the agri-food industry. Our value-driver framework is driven by the Q-study findings of respondents closely associated with the agri-food supply chain. This framework can provide supply chain stakeholders with a clear perception of blockchain affordances and serve as a guideline for utilizing appropriate features of technology that match organizations’ capabilities, core competencies, goals, and limitations. Therefore, it could assist top-level decision-makers in systematically evaluating parts of the organization to focus on and improve the infrastructure for successful blockchain implementation along the agri-food supply chain. We conclude by noting certain significant challenges that must be carefully addressed to successfully adopt blockchain technology

Determination of gyrA and parC mutations and prevalence of plasmid-mediated quinolone resistance genes in Escherichia coli and Klebsiella pneumoniae isolated from patients with urinary tract infection in Iran

Objectives: Fluoroquinolones (FQs) are recommended as the drugs of choice for the empirical treatment of urinary tract infections (UTIs). This study investigated the molecular determinants of FQ resistance in Escherichia coli and Klebsiella pneumoniae isolates in Iran. Methods: A total of 364 clinical isolates of E. coli (n = 144) and K. pneumoniae (n = 220) were collected from patients with UTI. Susceptibility of the isolates to ciprofloxacin, levofloxacin, gatifloxacin and nalidixic acid was evaluated by disk diffusion. The presence of qnrA, qnrB and qnrS genes was assessed by PCR. Nucleotide sequences of the gyrA and parC genes were determined. Results: Eighty-seven (60.4) and 15 (6.8) E. coli and K. pneumoniae isolates, respectively, were resistant to at least one of the tested FQs. Plasmid-mediated quinolone resistance (PMQR) genes were detected in 12.6 and 60.0 of FQ-resistant E. coli and K. pneumoniae, respectively. Whilst qnrB predominated in K. pneumoniae, qnrS was the most prevalent PMQR gene in E. coli. S83L (98.9) and D87N (59.8) were the most frequent mutations identified in GyrA of E. coli, and 55.2 (n = 48) of FQ-resistant E. coli isolates had mutation in ParC harbouring S80I and E84V substitutions. The GyrAS83L substitution was found in only one FQ-resistant K. pneumoniae isolate. Conclusions: FQ resistance was much more common in E. coli isolates than in K. pneumoniae. Whilst mutations in the drug target-encoding genes gyrA and parC were the major mechanisms involved in FQ resistance in E. coli, PMQR determinants commonly mediated FQ resistance in K. pneumoniae. © 201

Determination of gyrA and parC mutations and prevalence of plasmid-mediated quinolone resistance genes in Escherichia coli and Klebsiella pneumoniae isolated from patients with urinary tract infection in Iran

Objectives: Fluoroquinolones (FQs) are recommended as the drugs of choice for the empirical treatment of urinary tract infections (UTIs). This study investigated the molecular determinants of FQ resistance in Escherichia coli and Klebsiella pneumoniae isolates in Iran. Methods: A total of 364 clinical isolates of E. coli (n = 144) and K. pneumoniae (n = 220) were collected from patients with UTI. Susceptibility of the isolates to ciprofloxacin, levofloxacin, gatifloxacin and nalidixic acid was evaluated by disk diffusion. The presence of qnrA, qnrB and qnrS genes was assessed by PCR. Nucleotide sequences of the gyrA and parC genes were determined. Results: Eighty-seven (60.4) and 15 (6.8) E. coli and K. pneumoniae isolates, respectively, were resistant to at least one of the tested FQs. Plasmid-mediated quinolone resistance (PMQR) genes were detected in 12.6 and 60.0 of FQ-resistant E. coli and K. pneumoniae, respectively. Whilst qnrB predominated in K. pneumoniae, qnrS was the most prevalent PMQR gene in E. coli. S83L (98.9) and D87N (59.8) were the most frequent mutations identified in GyrA of E. coli, and 55.2 (n = 48) of FQ-resistant E. coli isolates had mutation in ParC harbouring S80I and E84V substitutions. The GyrAS83L substitution was found in only one FQ-resistant K. pneumoniae isolate. Conclusions: FQ resistance was much more common in E. coli isolates than in K. pneumoniae. Whilst mutations in the drug target-encoding genes gyrA and parC were the major mechanisms involved in FQ resistance in E. coli, PMQR determinants commonly mediated FQ resistance in K. pneumoniae. © 201