Effects of mistuning on dynamic behavior of nonlinear cyclic systems with lump masses and cubic nonlinearity

Mistuning in cyclic symmetric systems increases severely the forced response of system and splits the modes. This paper concerns with nonlinear behavior of mistuned cyclic systems. A nonlinear, mistuned model based on the method of multiple scales is proposed and formulated in which nonlinearity and mistuning parameter is assumed to be in of low order. Next, two mistuned systems were considered and solved by the multiple scale technique. Numerical results demonstrate that mistuning can lead to repeating and scattering of jump phenomena during the excitation frequency whereas in tuned cyclic system it occurs simultaneously (synchronously).Peer ReviewedPostprint (published version

Prevalence of Panton-valentine gene in Staphylococcus aureus isolated from clinical samples and healthy carriers in Gorgan city, north of Iran

Aim. Staphylococcus aureus (S. aureus) is a nosocomial and community acquired pathogen. S. aureus is a pathogen that causes several types of disease from skin infections to systemic diseases that is because of having several virulence factors such as enzymes, toxins, superantigens and Panton-Valentine leukocidin (pvl). pvl is a bi-component leukotoxin that destroy PMNs and monocytes and causes furunculosis, abscesses and necrotizing soft tissue infections in patients without any risk factors for such infections. The goal of this study was determine the prevalence of pvl gene in S. aureus isolated from patients and healthy carriers in Gorgan city, north of Iran. Methods. One hundred seventy isolates of S. aureus, 95 from patients and 75 healthy carriers, were collected during one year. After identification and purification, DNA extraction was done by phenol-chloroform method. Amplification of pvl gene was done by specific primer and polymerase chain reaction method. Results. Among the 170 isolates of S. aureus, 20 contained pvl gene. The frequency of isolates contained pvl gene in MRSA and MSSA isolates were 21.6, 19.3, which was not statistically significant. The frequency of these genes was not related to age, sex and source of isolation from patients. Conclusion. The frequency of pvl gene in this region were much higher than expected. © Copyright 2016 Edizioni Minerva Medica

Quantum teleportation with nonclassical correlated states in noninertial frames

Quantum teleportation is studied in noninertial frame, for fermionic case, when Alice and Bob share a general nonclassical correlated state. In noninertial frames two fidelities of teleportation are given. It is found that the average fidelity of teleportation from a separable and nonclassical correlated state is increasing with the amount of nonclassical correlation of the state. However, for any particular nonclassical correlated state, the fidelity of teleportation decreases by increasing the acceleration.Comment: 10 pages, 3 figures, expanded version to appear in Quantum Inf. Proces

Thermal stability of a special class of black hole solutions in F(R) gravity

In this paper, we work on the topological Lifshitz-like black hole solutions of a special class of vacuum $F(R)-$gravity that are static and spherically symmetric. We investigate geometric and thermodynamic properties of the solutions with due respect to the validity of the first law of thermodynamics. We examine the van der Waals like behavior for asymptotically AdS solutions with spherical horizon by studying the $P-v$, $G-T$ and $C_{Q,P}-r_{+}$ diagrams and find a consistent result. We also investigate the same behavior for hyperbolic horizon and interestingly find that the system under study can experience a phase transition with negative temperature.Comment: 14 pages with 7 captioned figures. Some additional notes are added. Accepted in EPJ

Frequency of Antimicrobial-Resistant Genes in Salmonella enteritidis Isolated from Traditional and Industrial Iranian White Cheeses

Iranian white cheese is one of the most important kinds of cheese produced in large scale with high consumption in the country. This dairy product transmits bacterial pathogens like Salmonella spp. Antibiotic resistant Salmonella are widespread in the world. This study was performed to evaluate the frequency of antimicrobial-resistant Salmonella enteritidis and related genes isolated from traditional and industrial Iranian white cheeses. A total of 200 traditional and industrial Iranian white cheeses were collected within Chaharmahal Va Bakhtiari province (southwest Iran). After culturing on specific media using standard bacterial tests the Salmonella sp. was isolated. For specific detection of S. enteritidis from other Salmonella strains sefA gene was studied. Finally, the antibiotic susceptibility patterns were investigated. Results showed that 17 % of cheese samples were contaminated by Salmonella and 5.5 % of specimens by S. enteritidis. The frequencies of resistance genes including tetA, tetB, tetC, cat3, and floR in isolated S. enteritidis were 36.4, 54.5, 81.8, 54.5, and 36.4 %, respectively. All isolated S. enteritidis were susceptible to ciprofloxacin, cefotaxime, and ceftazidime (100 %). In addition, most of them were resistance to chloramphenicol (64 %) and susceptible to gentamicin (98 %). The Salmonella contamination was more frequent in traditional Iranian white cheeses (11.5 %) as compared to industrial (5.5 %) samples (p < 0.05). As compared to industrial samples, high level of resistant genes in Salmonella enteritidis isolated from traditional Iranian white cheeses were observed (p < 0.05). Therefore, traditional Iranian white cheeses are important source of Salmonella contamination in the country hence examination of dairy products for the presence of this pathogen is importan

Critical gap analysis of merging sections at Kuala Lumpur middle ring road

At merging sections, drivers normally slow down and sometimes need to stop while seeking a suitable gap before merging with the mainstream. Thus, there will always be several observed rejected gaps and an accepted gap which can be used to determine the smallest average gap, so-called critical gap. This study was carried out to determine critical gap values at selected merging sections at the Jalan Tun Razak and the DUKE Expressway uses the Maximum Likelihood method. Data were collected by using videotaping method and the gap acceptance data were extracted for analysis. A gap acceptance event at highway merging sections in this study was redefined due to unavailability of stopping vehicles at the ramp junction. Therefore, the gap data were estimated starting from a ramp’s vehicle passing the end of gore marking to where it merges with the mainstream. The analysis of the critical gap takes into consideration accepted gaps greater than 5 seconds to avoid forced entry due to lead impedance of successive vehicles on mainstream. The critical gap values obtained in this study, according to vehicle classification were ranged between 4.5 to 5.0 seconds, which are slightly smaller if compared to critical gap values for particularly left turn from minor movement at priority junction of the Arahan Teknik (Jalan) 11/87 and the United States Highway Capacity Manual 2000. The findings shall help to study driving behavior of local drivers, especially at priority control facilities such as merging sections

Temperature Dependence Of The Electrical Resistivity Of LaxLu1-xAs

We investigate the temperature-dependent resistivity of single-crystalline films of LaxLu1-xAs over the 5-300 K range. The resistivity was separated into lattice, carrier and impurity scattering regions. The effect of impurity scattering is significant below 20 K, while carrier scattering dominates at 20-80 K and lattice scattering dominates above 80 K. All scattering regions show strong dependence on the La content of the films. While the resistivity of 600 nm LuAs films agree well with the reported bulk resistivity values, 3 nm films possessed significantly higher resistivity, suggesting that interfacial roughness significantly impacts the scattering of carriers at the nanoscale limit. (C) 2013 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.Microelectronics Research Cente

The effect of endurance and circuit resistance training on serum brain-derived neurotrophic factor and cortisol in inactive male students: A randomized clinical trial

زمینه و هدف: عامل رشد عصبی مشتق از مغز نقش مهمی در رشد و تکامل دستگاه عصبی دارد. تحقیقات حیوانی نشان داده اند که سطوح سرمی این فاکتور تحت تأثیر فعالیت ورزشی قرار می گیرد. هدف از انجام تحقیق حاضر تعیین تأثیر تمرین استقامتی و مقاومتی دایره ای بر عامل رشد عصبی مشتق شده از مغز و کورتیزول سرمی در مردان غیر فعال بود. روش بررسی: در این مطالعه کارآزمایی بالینی، 30 دانشجوی پسر غیر فعال به طور تصادفی به سه گروه تمرین استقامتی، تمرین مقاومتی و کنترل تقسیم شدند. آزمودنی های گروه استقامتی برنامه تمرینی استقامتی شامل 45-30 دقیقه دوی تناوبی با شدت 75-60 درصد ضربان قلب بیشینه را به مدت چهار هفته اجرا کردند. آزمودنی های گروه های تمرین مقاومتی نیز سه جلسه در هفته، به مدت چهار هفته تمرین مقاومتی دایره ای با شدت 75-60 درصد یک تکرار بیشینه را انجام دادند. قبل و 48 ساعت بعد از دوره‌ی تحقیق، نمونه گیری خونی برای سنجش مقادیر سرمی عامل رشد عصبی مشتق شده از مغز و کورتیزول از آزمودنی ها به عمل آمد. یافته ها: تمرین استقامتی و مقاومتی دایره ای غلظت سرمی عامل رشد عصبی مشتق شده از مغز را به طور معنی داری افزایش داد. در بررسی نتایج پس آزمون تفاوتی بین گروه های تمرینی مشاهده نشد؛ ولی بین دو گروه تمرین استقامتی و گروه کنترل تفاوت معنی دار بود. تمرین استقامتی و مقاومتی تأثیر معنی داری بر سطوح کورتیزول سرمی نداشت. نتیجه گیری: بر اساس یافته های این مطالعه، تمرین استقامتی و مقاومتی دایره ای باعث افزایش فاکتورهای نروتروفیک می شود که ممکن است بدین طریق باعث ایجاد سازگاری های ساختاری و عملکردی در دستگاه عصبی شود

Antibiotic resistance pattern of some Vibrio strains isolated from seafood

The present study was aimed to evaluate the antimicrobial resistance and the presence of antibiotic resistance genes in Vibrios spp. isolated from seafood. A total of 72 isolates of Vibrio in 6 species including V. parahaemolyticus, V. vulnificus, V. alginolyticus, V. harveyi, V. mimicus and V. cholerae were examined. The results revealed that all isolates were expressing multiple antibiotic resistances. Of the 72 strains tested, 70 were resistant to ampicillin (97.2%), 60 to gentamycin (83.3%) and 56 to penicillin (77.7%). Eight strains were resistant to 4 antibiotic, 19 resistant to five antibiotics, 10 to six antibiotics, 34 to seven antibiotics and one to eight antibiotics. Results also revealed that 20 Vibrio strains (27.7% of total examined strains) contained one to three of the antibiotic resistance genes. StrB, tetS and ermB genes coding for streptomycin, tetracycline and erythromycin resistance were found in 18, 6, 5 isolates, respectively and Sulfamethoxazole resistance gene, sul2, was not detected in this study. Detection of resistance genes in Vibrio strains obtained from seafood is considered as a potential danger for consumers and also suggests that these resistance determinants might be further disseminated in habitats, thus constituting a serious health risks to human