Exact solution for large amplitude flexural vibration of nanobeams using nonlocal Euler-Bernoulli theory

In this paper, nonlinear free vibration of nanobeams with various end conditions is studied using the nonlocal elasticity within the frame work of Euler-Bernoulli theory with von K´arm´an nonlinearity. The equation of motion is obtained and the exact solution is established using elliptic integrals. Two comparison studies are carried out to demonstrate accuracy and applicability of the elliptic integrals method for nonlocal nonlinear free vibration analysis of nanobeams. It is observed that the phase plane diagrams of nanobeams in the presence of the small scale effect are symmetric ellipses, and consideration the small scale effect decreases the area of the diagram

Evaluation and comparison of SYBR Green I Real-Time PCR and TaqMan Real-Time PCR methods for quantitative assay of Listeria monocytogenes in nutrient broth and milk

Specific traditional plate count method and real-time PCR systems based on SYBR Green I and TaqMan technologies using a specific primer pair and probe for amplification of iap-gene were used for quantitative assay of Listeria monocytogenes in seven decimal serial dilution series of nutrient broth and milk samples containing 1.58 to 1.58×107 cfu /ml and the real-time PCR methods were compared with the plate count method with respect to accuracy and sensitivity. In this study, the plate count method was performed using surface-plating of 0.1 ml of each sample on Palcam Agar. The lowest detectable level for this method was 1.58×10 cfu/ml for both nutrient broth and milk samples. Using purified DNA as a template for generation of standard curves, as few as four copies of the iap-gene could be detected per reaction with both real-time PCR assays, indicating that they were highly sensitive. When these real-time PCR assays were applied to quantification of L. monocytogenes in decimal serial dilution series of nutrient broth and milk samples, 3.16×10 to 3.16×105 copies per reaction (equals to 1.58×103 to 1.58×107 cfu/ml L. monocytogenes) were detectable. As logarithmic cycles, for Plate Count and both molecular assays, the quantitative results of the detectable steps were similar to the inoculation levels

Computed tomography and magnetic resonance imaging of hydatid disease: A pictorial review of uncommon imaging presentations

Hydatid disease (HD), also known as echinococcal disease or echinococcosis, is a worldwide zoonosis with a wide geographic distribution. It can be found in almost all parts of the body and usually remains silent for a long period of time. Clinical history can be varied based on the location, size, host immune response, and complications. The most common imaging modalities used for diagnosis and further evaluations of HD are ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). Although conventional radiography may be the first used tool, rarely can lead to a definite judgment. Clinical indications and cyst location may alter the choice of imaging. MRI and CT would be useful when the involved area is inaccessible for ultrasound or surgical treatment is required. CT is particularly valuable for osseous organ involvements and the presence of calcifications in the cyst and also demonstrates the size, number, and local complications. MRI can differentiate HD from neoplasms in cases with an unusual appearance on imaging. Moreover, it is preferable in biliary or neural involvements. Besides, more detailed images of MRI and CT could help to resolve the diagnostic uncertainty. Imaging is the main stem for HD diagnosis. Brain, orbit, muscle, bone, and vascular structures are less commonly involved areas. Familiarity with typical clinical presentation, CT scan and MR imaging findings of HD in this sites facilitate the radiologic diagnosis and guiding appropriate treatment. © 2021 The Author(s

Molecular identification and antifungal susceptibility pattern of non-albicans candida species isolated from vulvovaginal candidiasis

Background: Vulvovaginal candidiasis (VVC) is an important health problem caused by Candida spp. The aim of this study was molecular identification, phylogenetic analysis, and evaluation of antifungal susceptibility of nonalbicans Candida isolates from VVC. Methods: Vaginal secretion samples were collected from 550 vaginitis patients at Sayyad Shirazi Medical and Educational Center of Gorgan (Golestan Province, Iran) from May to October 2015. Samples were analyzed using conventional mycological and molecular approaches. Clinical isolates were analyzed with specific PCR using CGL primers, and the internal transcribed spacer region and the D1-D2 domain of the large-subunit rRNA gene were amplified and sequenced. Susceptibility to amphotericin B, fluconazole, itraconazole, and clotrimazole was determined by the guidelines of the Clinical and Laboratory Standard Institute. Results: In total, 35 non-albicans Candida isolates were identified from VVC patients. The isolates included 27 strains of Candida glabrata (77.1), 5 Candida krusei (Pichia kudriavzevii; 14.3), 2 Candida kefyr (Kluyveromyces marxianus; 5.7), and 1 Candida lusitaniae (Clavispora lusitaniae; 2.9). The fungicides itraconazole and amphotericin B were effective against all species. One isolate of C. glabrata showed resistance to fluconazole and clotrimazole, and 26 isolates of C. glabrata indicated dose-dependent susceptibility to fluconazole. C. lusitaniae was susceptible in a dose-dependent manner to fluconazole and resistant to clotrimazole. Conclusions: Non-albicans Candida spp. are common agents of vulvovaginitis, and C. glabrata is the most common species in the tested patients. © 2018, Pasteur Institute of Iran. All rights reserved

Optimal β-blocker for prevention of atrial fibrillation after on-pump coronary artery bypass graft surgery: Carvedilol versus metoprolol

Background: Atrial fibrillation (AF) is the most common arrhythmia after coronary artery bypass graft (CABG) surgery. It has been shown that prophylactic oral β-blocker administration reduces the incidence of post-CABG AF. However, the optimal β-blocker has not been identified. Objective: This study sought to determine whether oral carvedilol (with its unique anti-inflammatory and antioxidant properties) is more effective than oral metoprolol for prevention of AF after CABG surgery. Methods: Between April 2006 and December 2006, 120 patients (63 men, mean age 61 ± 9.4 years) who were scheduled to undergo their first on-pump CABG were enrolled in this study. The patients were randomized in a prospective 1:1 manner to receive either oral carvedilol (n = 60) or oral metoprolol (n = 60). The end point of the study was the occurrence of the new-onset AF during the first 5 days aftere CABG. Results: AF occurred in 29 of 120 patients (24.0). The incidence of postoperative AF was 15.0 (9 of 60) in the carvedilol group and 33 (20 of 60) in the metoprolol group (P = .022). The carvedilol group was treated with mean daily dose of 46 ± 9 mg and metoprolol group with mean daily dose of 93 ± 11 mg. There were no differences between the study groups regarding any known preoperative, perioperative, or postoperative characteristics (all values were P >.05). No significant adverse effect was observed in either group. Conclusion: This prospective study suggested that oral carvedilol is more effective than oral metoprolol in the prevention of AF after on-pump CABG. It is well tolerated when started before and continued after the surgery. However, further prospective studies are needed to clarify this issue. © 2007 Heart Rhythm Society

Fungal peritonitis in Iranian children on continuous ambulatory peritoneal dialysis: a national experience.

INTRODUCTION. Fungal peritonitis (FP), causing catheter obstruction, dialysis failure, and peritoneal dysfunction, is a rare but serious complication of peritoneal dialysis. In this study, the frequency and risk factors of FP are evaluated in children who underwent peritoneal dialysis. MATERIALS AND METHODS. A retrospective multicenter study was performed at the 5 pediatric peritoneal dialysis centers in Iran from 1971 to 2006, and FP episodes among 93 children were reviewed. Risk ratios were calculated for the clinical and demographic variables to determine the risk factors of FP. RESULTS. Ninety-three children aged 39 months on average were included in study. Sixteen out of 155 episodes of peritonitis were fungi infections, all by Candida albicans. The risk of FP was higher in those with relapsing bacterial peritonitis (P = .009). Also, all of the patients had received antibiotics within the 1 month prior to the development of FP. Catheters were removed in all patients after 1 to 7 days of developing FP. Six out of 12 patients had catheter obstruction and peritoneal loss after the treatment and 5 died due to infection. CONCLUSIONS. Fungal peritonitis, accompanied by high morbidity and mortality in children should be reduced by prevention of bacterial peritonitis. Early removal of catheter after recognition of FP should be considered

Fungal peritonitis in Iranian children on continuous ambulatory peritoneal dialysis: a national experience.

INTRODUCTION. Fungal peritonitis (FP), causing catheter obstruction, dialysis failure, and peritoneal dysfunction, is a rare but serious complication of peritoneal dialysis. In this study, the frequency and risk factors of FP are evaluated in children who underwent peritoneal dialysis. MATERIALS AND METHODS. A retrospective multicenter study was performed at the 5 pediatric peritoneal dialysis centers in Iran from 1971 to 2006, and FP episodes among 93 children were reviewed. Risk ratios were calculated for the clinical and demographic variables to determine the risk factors of FP. RESULTS. Ninety-three children aged 39 months on average were included in study. Sixteen out of 155 episodes of peritonitis were fungi infections, all by Candida albicans. The risk of FP was higher in those with relapsing bacterial peritonitis (P = .009). Also, all of the patients had received antibiotics within the 1 month prior to the development of FP. Catheters were removed in all patients after 1 to 7 days of developing FP. Six out of 12 patients had catheter obstruction and peritoneal loss after the treatment and 5 died due to infection. CONCLUSIONS. Fungal peritonitis, accompanied by high morbidity and mortality in children should be reduced by prevention of bacterial peritonitis. Early removal of catheter after recognition of FP should be considered