Preliminary studies on the identification of vaccinal mimotopes of bovine viral diarrhoea virus using combinatorial peptide libraries

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Harmonic Response of Large Engineering Structures with Nonlinear Modifications

In a structural design, the structure may need to be modified and for each modification its dynamic characteristics may need to be determined by reanalyzing the structure dynamically. Since computational time and cost are very critical in design processes, structural modification methods become decisive, particularly for large systems, in predicting the dynamic behavior of modified structures from those of the original and modifying structures. Due to nonlinearity in most engineering structures, linearity assumption may not be applicable to all cases. Then, well known structural modification methods can not be directly used, and it is required to employ a nonlinear structural modification method. In this paper, a structural modification/coupling method proposed in an earlier study is extended for nonlinear modification/coupling. The nonlinearities are quasilinearised using describing function method, and thus nonlinear internal force vector is expressed in terms of a response-dependent matrix which can be regarded as a response level dependent "equivalent stiffness matrix", called "nonlinearity matrix". Then the method developed for linear structural modification/coupling is employed by using an iterative solution procedure. Three case studies are presented in this paper. In the first case study, a nonlinear test structure used in an earlier study is employed and the frequency responses of the system at different forcing levels are calculated by using the approach suggested. Then they are compared with experimental results. Secondly, a simple discrete system is analyzed to demonstrate the accuracy of the approach proposed. Lastly, a large scale model is considered to illustrate the applicability of the approach proposed to large order systems

Dynamic Decoupling of Nonlinear Systems

Structural decoupling problem has been well investigated for three decades and led to several decoupling methods. In spite of the inherent nonlinearities in a structural system in various forms all decoupling studies are for linear systems. In this study, decoupling problem for nonlinear systems is addressed for the first time and a method is proposed for calculating the frequency response functions of a substructure decoupled from a coupled nonlinear structure where nonlinearity can be modelled as a single nonlinear element. The method proposed is validated through simulated case studies

Nonlinear structural modification and nonlinear coupling

Structural modification methods were proved to be very useful for large structures, especially when modification is local. Although there may be inherent nonlinearities in a structural system in various forms such as clearances, friction and cubic stiffness, most of the structural modification methods are for linear systems. The method proposed in this work is a structural modification/coupling method developed previously, and extended to systems with nonlinear modification and coupling. The method is most useful for large linear structures with nonlinear local modification or coupling. It is based on expressing nonlinear internal force vector in a nonlinear system as a response level dependent "equivalent stiffness matrix" (the so-called "nonlinearity matrix") multiplied by the displacement vector, through quasilinearizing the nonlinearities using describing functions. Once nonlinear internal force vector is expressed as a matrix multiplication form then several structural modification and/or coupling methods can easily be used for nonlinear systems, provided that an iterative solution procedure is employed and convergence is obtained. In the proposed approach the nonlinear FRFs of a modified/ coupled system are calculated from those of the original system and dynamic stiffness matrix of the nonlinear modifying system. Formulations and sample applications of the proposed approach for each of the following cases are given, nonlinear modification of a linear system with and without adding new degrees of freedom, and elastic coupling of a nonlinear subsystem to a main linear system with linear or nonlinear elements. Case studies are given for the verification of the method and then a real life application of the method is presented

Efficacy of proximal tibial focal-dome type osteotomy on medial joint laxity

Objective

Evaluation of Antioxidant, Antimicrobial, Antityrosinase and Cytotoxic Potentials of Isatis cappadocica subsp. alyssifoli as a Potent Pharmaceutical Resource

WOS: 000464004500002Isatis species, which are endemic across most of Turkey, exhibit antibacterial, anticancer and antiviral effects. the aim of this study was to determine of antioxidant, antimicrobial, tyrosinase inhibitor, cytotoxic activities, and phenolic profile of polar extracts of Isatis cappadocica Desv. We analyzed the antioxidant properties of extracts using total phenolic content (TPC), ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), and 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging activity. the phenolic composition of methanolic extract of I. cappadocica was analyzed by reverse phase high performance liquid chromatography (RP-HPLC). Extracts' antimicrobial properties were evaluated based on the agar well diffusion technique. Tyrosinase inhibitory activity was measured colorimetrically. Methanolic extract yielded better FRAP and CUPRAC results and aqueous extract yielded better DPPH activity. Benzoic acid, and sinapic acid were detected as major phenolic compounds. Methanolic extract was particularly effective against all the bacteria investigated, apart from Yersinia pseudotuberculosis. Methanol extract was exhibited tyrosinase inhibitory activity. the methanol extract has caused to death of cells by dosage in the high concentrations cytotoxic activity on the PC-3 and 3T3 cell lines. the results showed that I. cappadocica could be used as a natural source in the food, cosmetic, and drug industries due to their rich antioxidant, antimicrobial, cytotoxic and tyrosinase inhibitor activities

Prevalence of rotavirus genotypes in children younger than 5 years of age before the introduction of a universal rotavirus vaccination program: Report of Rotavirus Surveillance in Turkey

PubMedID: 25437502Background: Group A rotaviruses are the most common causative agent of acute gastroenteritis among children less than 5 years of age throughout the world. This sentinel surveillance study was aimed to obtain baseline data on the rotavirus G and P genotypes across Turkey before the introduction of a universal rotavirus vaccination program. Methods: Rotavirus antigen-positive samples were collected from 2102 children less than 5 years of age who attended hospitals participating in the Turkish Rotavirus Surveillance Network. Rotavirus antigen was detected in the laboratories of participating hospitals by commercial serological tests such as latex agglutination, immunochromatographic test or enzyme immunoassay. Rotavirus G and P genotypes were determined by reverse transcription polymerase chain reaction (RT-PCR) using consensus primers detecting the VP7 and VP4 genes, followed by semi-nested type-specific multiplex PCR. Results: RT-PCR found rotavirus RNA in 1644 (78.2%) of the samples tested. The highest rate of rotavirus positivity (38.7%) was observed among children in the 13 to 24 month age group, followed by children in the age group of 25 to 36 months (28.3%). A total of eight different G types, six different P types, and 42 different G-P combinations were obtained. Four common G types (G1, G2, G3, and G9) and two common P types (P[8] and P[4]) accounted for 95.1% and 98.8% of the strains, respectively. G9P[8] was the most common G/P combination found in 40.5% of the strains followed by G1P[8] (21.6%), G2P[8] (9.3%), G2P[4] (6.5%), G3P[8] (3.5%), and finally, G4P[8] (3.4%). These six common genotypes included 83.7% of the strains tested in this study. The rate of uncommon genotypes was 14%. Conclusion: The majority of the strains analyzed belonged to the G1-G4 and G9 genotypes, suggesting high coverage of current rotavirus vaccines. This study also demonstrates a dramatic increase in G9 genotype across the country. © 2014 Durmaz et al

Prevalence of Rotavirus Genotypes in Children Younger than 5 Years of Age before the Introduction of a Universal Rotavirus Vaccination Program: Report of Rotavirus Surveillance in Turkey

Background: Group A rotaviruses are the most common causative agent of acute gastroenteritis among children less than 5 years of age throughout the world. This sentinel surveillance study was aimed to obtain baseline data on the rotavirus G and P genotypes across Turkey before the introduction of a universal rotavirus vaccination program

The total number of rotavirus RNA-positive samples and distribution of major genotypes in different age groups.

<p>The total number of rotavirus RNA-positive samples and distribution of major genotypes in different age groups.</p