Correlation of ciprofloxacin resistance with the AdeABC efflux system in Acinetobacter baumannii clinical isolates

Background: Acinetobacter baumannii is one of the most important pathogens capable of colonization in burn patients, leading to drug-resistant wound infections. This study evaluated the distribution of the AdeABC efflux system genes and their relationship to ciprofloxacin resistance in A. baumannii isolates collected from burn patients. Methods: A total of 68 A. baumannii clinical strains were isolated from patients hospitalized in Motahari Burns Center in Tehran, Iran. Ciprofloxacin susceptibility was tested by the disk diffusion and agar dilution methods. PCR amplification of the adeRS-adeB drug efflux genes was performed for all resistant and susceptible isolates. To assess the role of the drug efflux pump in ciprofloxacin susceptibility, carbonyl cyanide 3-chlorophenylhydrazone (CCCP) was used as an efflux pump inhibitor (EPI). Results: Approximately 95.6% of the Acinetobacter isolates were resistant to ciprofloxacin, with minimum inhibitory concentration (MIC) values ranging from 4 to ≥128 μg/mL. The susceptibility of 86.1% of the resistant isolates increased by factors of 2 to 64 in the presence of CCCP. All resistant isolates were positive for the adeRS-adeB genes, and 73.2% of them had mutations in the AdeRS regulatory system. Conclusions: The results showed that AdeABC genes are common in A. baumannii, which might be associated with ciprofloxacin non-susceptibility, as indicated by the observed linkage to the presence of the genes essential for the activity of the AdeABC, several single mutations occurring in the adeRS regulatory system, and an increase of ciprofloxacin susceptibility in the presence of a CCCP EPI. © The Korean Society for Laboratory Medicin

Simultaneous effect of temperature and site altitude on generators output

The effect of environmental conditions of the site must be considered as one of the most important aspects of designing generators as well as theoretic calculations and considerations. The real amounts which are measurable on the sites under real conditions are usually different from the rated values of the generators. In this paper we exerted this consideration and a typical model of generator produced by Ansaldo Energia was selected and studied. The material of the generator application guide and the measured values on site are used to get related curves of the environmental conditions effect, such as the effect the site altitude and the ambient temperature, on generator rated values. The practical and measured values of this model of generator which has been installed on Parand and Oroumieh sites in Iran are used for verification of the results of this paper and the related error is calculated. We claim this technical research has not been done before with such mentioned considerations and necessities. This paper gives the necessary instruction to evaluate the applicability and the generator characteristic data at different operating conditions (load, voltage, power factor, site and cooling condition). This study enables the designer to evaluate the generator behavior under the customer requirements and environmental conditions as well as to prepare the necessary proposed documentation for the client. © 2011 Praise Worthy Prize S.r.l. - All rights reserved

Hybrid Turbo-Shaft Engine Digital Twinning for Autonomous Aircraft via AI and Synthetic Data Generation

Autonomous aircraft are the key enablers of future urban services, such as postal and transportation systems. Digital twins (DTs) are promising cutting-edge technologies that can transform the future transport ecosystem into an autonomous and resilient system. However, since DT is a data-driven solution based on AI, proper data management is essential in implementing DT as a service (DTaaS). One of the challenges in DT development is the availability of real-life data, particularly for training algorithms and verifying the functionality of DT. The current article focuses on data augmentation through synthetic data generation. This approach can facilitate the development of DT in case the developers do not have enough data to train the machine learning (ML) algorithm. The current twinning approach provides a prospective ideal state of the engine used for proactive monitoring of the engine’s health as an anomaly detection service. In line with the track of unmanned aircraft vehicles (UAVs) for urban air mobility in smart city applications, this paper focuses specifically on the common hybrid turbo-shaft in drones/helicopters. However, there is a significant gap in real-life similar synthetic data generation in the UAV domain literature. Therefore, rolling linear regression and Kalman filter algorithms were implemented on noise-added data, which simulate the data measured from the engine in a real-life operational life cycle. For both thermal and hybrid models, the corresponding DT model has shown high efficiency in noise filtration and a certain amount of predictions with a lower error rate on all engine parameters except the engine torque

Optimal FRP Jacket Placement in RC Frame Structures Towards a Resilient Seismic Design

This paper proposes an optimal plan for seismically retrofitting reinforced concrete (RC) frame structures. In this method, the columns are wrapped by fiber-reinforced polymer (FRP) layers along their plastic hinges. This technique enhances their ductility and increases the resiliency of the structure. Two meta-heuristic algorithms (i.e., genetic algorithm and particle swarm optimization) are adopted for this purpose. The number of FRP layers is assumed to be the design variable. The objective of the optimization procedure was to provide a uniform usage of plastic hinge rotation capacity for all the columns, while minimizing the consumption of the FRP materials. Toward this aim, a single objective function containing penalty terms is introduced. The seismic performance of the case study RC frame was assessed by means of nonlinear pushover analyses, and the capacity of the plastic hinge rotation for FRP-confined columns was evaluated at the life safety performance level. The proposed framework was then applied to a non-ductile low-rise RC frame structure. The optimal retrofit scheme for the frame was determined, and the capacity curve, inter-story drift ratios, and fragility functions were computed and compared with alternative retrofit schemes. The proposed algorithm offers a unique technique for the design of more resilient structures.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

On the Dynamic Capacity of Concrete Dams

The purpose of this joint contribution is to study the maximum dynamic load concrete dams can withstand. The so-called "dynamic capacity functions" for these infrastructures seems now technically and commercially feasible thanks to the modern finite element techniques, hardware capabilities, and positive experiences collected so far. The key topics faced during the dynamic assessment of dams are also discussed using different point of view and examples, which include: the selection of dynamic parameters, the progressive level of detail for the numerical simulations, the implementation of nonlinear behaviors, and the concept of the service and collapse limit states. The approaches adopted by local institutions and engineers on the subject of dam capacity functions are discussed using the authors' experiences, and an overview of time and resources is outlined to help decision makers. Three different concrete dam types (i.e., gravity, buttress, and arch) are used as case studies with different complexities. Finally, the paper is wrapped up with a list of suggestions for analysts, the procedure limitations, and future research needs

Interventions based on PRECEDE-PROCEED for promoting safety behaviors in Primary school boys

Introduction & Objective: Pedestrian injuries are a significant source of morbidity, mortality and disability among children. Prevention of these injuries is thus a major priority for public health and requires a comprehensive approach and educational strategies. The purpose of this study was designing and evaluation of an educational program, based on the PRECEED-PROCEED model for improvement of safety behavior in primary school boys. Materials & Methods: This study is a field trial carried out in 6th areas of Tehran in 2007. Participants (n=88) were 10 – 11 year old who followed by items measuring the PRECEED-PROCEED model before and after two months of intervention. The collected data were analyzed with T test, X2 and pair T test using SPSS software. Results: After participating in educational program, significant improvements were found in knowledge, attitude, behavior, enabling and reinforcing factors of the components of PRECEEDPROCEED model. Conclusion: The findings suggest the beneficial effects of educational intervention based on the PRECEDE-PROCEED model on improving the safety behavior. It can be recommended that health education plan be used on educational models

Metallo�β�lactamase�mediated resistance among clinical carbapenem�resistant Pseudomonas aeruginosa isolates in northern Iran: A potential threat to clinical therapeutics

Objective: Carbapenems are effective agents to treat multidrug�resistant (MDR) strains of bacteria, including Pseudomonas aeruginosa. However, there is a potential threat of emergence of carbapenem�resistant P. aeruginosa (CRPA). The aim of this study was to determine antibiotic susceptibility patterns and metallo�beta�lactamase (MBL)�mediated resistance in clinical P. aeruginosa isolates. Materials and Methods: Different clinical specimens were subjected to conventional culture�based identification of P. aeruginosa. Antimicrobial susceptibility patterns and MBL production were evaluated using the Kirby�Bauer and combined double�disk synergy test methods, respectively. Multiplex polymerase chain reaction was performed to investigate the presence of the blaIMP, blaVIM, blaNDM, blaSPM, and blaSIM genes. Results: A total of 71 clinical P. aeruginosa isolates were recovered, of which 28.17 were identified as CRPA. The most active antibiotics were colistin and polymyxin B (92.96 susceptibility to each). A total of 35 and 50 of CRPA isolates were MDR and extensively drug�resistant (XDR), respectively. MBL activity was shown in 20 of CRPA. A total of 90, 40, and 5 of CRPA isolates harbored the blaIMP, blaVIM, and blaNDM genes, respectively. No correlation was found between the MBL�encoding genes of P. aeruginosa and patient characteristics. Conclusion: Although the prevalence of CRPA in our therapeutic centers was relatively low, this rate of carbapenem resistance reflects a threat limiting treatment choices. A high prevalence of MDR/XDR phenotypes among the MBL�producer isolates suggests the need for continuous assessment of antimicrobial susceptibility and surveillance of antibiotic prescription. In addition, infection control measures are needed to prevent further dissemination of these organisms. © 2018 Tzu Chi Medical Journal | Published by Wolters Kluwer - Medknow

Fine-structure diagnostics of neutral carbon toward HE 0515-4414

New high-resolution high signal-to-noise spectra of the $z=1.15$ damped Lyman $\alpha$ (DLA) system toward the quasi-stellar object HE 0515-4414 reveal absorption lines of the multiplets 2 and 3 in \ion{C}{i}. The resonance lines are seen in two components with total column densities of $\log N=13.79\pm0.01$ and $\log N=13.36\pm0.01$, respectively. The comparision of theoretical calculations of the relative fine-structure population with the ratios of the observed column densities suggests that the \ion{C}{i} absorbing medium is either very dense or exposed to very intense UV radiation. The upper limit on the local UV energy density is 100 times the galactic UV energy density, while the upper limit on the \ion{H}{i} number density is 110 cm$^{-3}$. The excitation temperatures of the ground state fine-structure levels of $T=15.7$ and $T=11.1$ K, respectively, are consistent with the temperature-redshift relation predicted by the standard Friedmann cosmology. The cosmic microwave background radiation (CMBR) is only a minor source of the observed fine-structure excitation.Comment: 5 pages, 5 figures, uses A&A macro package, gzipped tar archive, accepted by A&

Prevalence of Subclinical Hypothyroidism in Chronic Kidney Disease in a Population-based Study: Tehran Thyroid Study

Background: Chronic kidney disease (CKD) is a rising public health concern that has detrimental effects on cardiovascular health and overall survival. Subclinical hypothyroidism (SCH) has been associated with poor outcomes in the general population. It is thought to be more prevalent in CKD subjects, and their coexistence may contribute to poor outcomes in these patients. We aimed to determine the prevalence of SCH in CKD. Methods: Using data from the Tehran thyroid study, which is a prospective population-based cohort study, adult subjects with an estimated Glomerular Filtration Rate (eGFR) of 60 mL/min/1.73 m2 or less were selected for studying the prevalence of thyroid abnormalities, as well as other known cardiovascular risk factors. Results: Of 5,626 subjects recruited, 823 (14.6) individuals had CKD. Individuals with CKD were older, heavier, had a higher prevalence of diabetes, higher serum thyrotropin, and thyroid peroxidase anti-body levels, but lower free thyroxine levels. The prevalence of SCH was 7.3 and 5.2 (P < 0.001) in kidney disease and non-kidney disease subjects, respectively. However, there was no difference in the risk of SCH between CKD and non-CKD subjects after adjustment for age, sex, BMI, smoking, and TPOAb (OR: 1.28; 95CI, 0.89 - 1.83). None of the metabolic markers compared between the CKD subgroups of those with and without SCH remained statistically significantly different after adjusting for age and gender. Conclusions: The prevalence of SCH was not higher in CKD after controlling for confounding factors. Besides, CKD subjects with and without SCH had no different metabolic parameters. © 2021, International Journal of Endocrinology and Metabolism