Reducing Packet Overhead in Mobile IPv6

Common Mobile IPv6 mechanisms, Bidirectional tunneling and Route optimization, show inefficient packet overhead when both nodes are mobile. Researchers have proposed methods to reduce packet overhead regarding to maintain compatible with standard mechanisms. In this paper, three mechanisms in Mobile IPv6 are discussed to show their efficiency and performance. Following discussion, a new mechanism called Improved Tunneling-based Route Optimization is proposed and due to performance analysis, it is shown that proposed mechanism has less overhead comparing to common mechanisms. Analytical results indicate that Improved Tunneling-based Route Optimization transmits more payloads due to send packets with less overhead

Antibacterial Activity of Diode Laser and Sodium Hypochlorite in Enterococcus Faecalis-Contaminated Root Canals

Introduction: The aim of the present in vitro study was to evaluate the disinfection ability of 980-nm diode laser in comparison with sodium hypochlorite (NaOCl) as a common root canal irrigant in canals infected with Enterococcus faecalis (E. faecalis). Methods and Materials: The root canals of 18 extracted single-rooted premolars were prepared by rotary system. After decoronation, the roots were autoclaved. One specimen was chosen for the negative control, and the remaining teeth were incubated with E. faecalis suspension for two weeks. Subsequently, one specimen was selected as the positive control and the remaining samples were divided into two groups (n=8). The samples of the first group were irrigated with 5.25% NaOCl and the second group were treated with a 980-nm diode laser. Microbial samples were taken from the root canals and bacterial cultivation was carried out. The average value and the standard deviation of colony-forming units (CFU) of each specimen were measured using descriptive statistics. The student’s t-test was used to compare the reduction in CFU in each group. The equality of variance of CFU was measured by the Levene’s test. Results: NaOCl resulted in 99.87% removal of the bacteria and showed significantly more antibacterial effect  compared to the 980-nm diode laser which led to 96.56% bacterial reduction (P<0.05). Conclusion: Although 5.25% NaOCl seems to reduce E. faecalis more effectively, the diode laser also reduced the bacterial count. Therefore a 980-nm diode laser could be considered as a complementary disinfection method in root canal treatment.Keywords: Diode Laser; Enterococcus faecalis; Root Canal Disinfection; Root Canal Irrigan

Retinal Vessels Segmentation Techniques and Algorithms: A Survey

Retinal vessels identification and localization aim to separate the different retinal vasculature structure tissues, either wide or narrow ones, from the fundus image background and other retinal anatomical structures such as optic disc, macula, and abnormal lesions. Retinal vessels identification studies are attracting more and more attention in recent years due to non-invasive fundus imaging and the crucial information contained in vasculature structure which is helpful for the detection and diagnosis of a variety of retinal pathologies included but not limited to: Diabetic Retinopathy (DR), glaucoma, hypertension, and Age-related Macular Degeneration (AMD). With the development of almost two decades, the innovative approaches applying computer-aided techniques for segmenting retinal vessels are becoming more and more crucial and coming closer to routine clinical applications. The purpose of this paper is to provide a comprehensive overview for retinal vessels segmentation techniques. Firstly, a brief introduction to retinal fundus photography and imaging modalities of retinal images is given. Then, the preprocessing operations and the state of the art methods of retinal vessels identification are introduced. Moreover, the evaluation and validation of the results of retinal vessels segmentation are discussed. Finally, an objective assessment is presented and future developments and trends are addressed for retinal vessels identification techniques.https://doi.org/10.3390/app802015

Cognitive Taxonomy of Items Based on Capability- Complexity Model Case Study: differential calculi test items

Developing hard items with complicate calculation algorithms cause to in appropriate trends such as teaching to the test and test preparation strategies in examinees. Having exact educational standards and applying taxonomy models, however, will help to obtain fine evaluation of educational programs, contents and students achievement.  In this manuscript, a small sample of differential calculi multiple choice items test has been studied in behavioral objectives framework which is based on combining the Bloom and Web approaches; the goal was to illustration of capability- complexity approach in taxonomy of test items. Twenty items of a 30 items test battery which administered on a 3409 sample of students has been classified by capability-complexity approach. Outcomes of 3 items have been reported in this article.  Results had shown all the test items measuring procedural knowledge at level three. 92% of items were abstract, and simultaneously recalling multiple calculation algorithms require for responding correctly to each item. Tasks with one calculation algorithm and lower complexity had better statistical parameters such as scalability and their item information functions yielded much more information about examinees capability

A New Label-Free Technique for Analysing Evaporation Induced Self-Assembly of Viral Nanoparticles Based on Enhanced Dark-Field Optical Imaging

Nanoparticle self-assembly is a complex phenomenon, the control of which is complicated by the lack of appropriate tools and techniques for monitoring the phenomenon with adequate resolution in real-time. In this work, a label-free technique based on dark-field microscopy was developed to investigate the self-assembly of nanoparticles. A bio-nanoparticle with complex shape (T4 bacteriophage) that self-assembles on glass substrates upon drying was developed. The fluid flow regime during the drying process, as well as the final self-assembled structures, were studied using dark-field microscopy, while phage diffusion was analysed by tracking of the phage nanoparticles in the bulk solutions. The concentrations of T4 phage nanoparticles and salt ions were identified as the main parameters influencing the fluid flow, particle motion and, consequently, the resulting self-assembled structure. This work demonstrates the utility of enhanced dark-field microscopy as a label-free technique for the observation of drying-induced self-assembly of bacteriophage T4. This technique provides the ability to track the nano-sized particles in different matrices and serves as a strong tool for monitoring self-assembled structures and bottom-up assembly of nano-sized building blocks in real-time

A numerical study of the nanofluid mixtures inside a Buoyancy-driven cavity in the presence of a variable magnetic field

While magnetic flow applications have become a topic of great interest for decades, the coupling between fluid flow and electromagnetic forces is not straightforward. Therefore, the necessity of a robust guideline to simulate these types of problems has become apparent. Moreover, the heat transfer capabilities and the interaction between electromagnetic forces such as Lorentz and Kelvin require further investigation.In this regard, two objectives are pursued to address the noted issues. First, a robust and flexible solution framework using User-Defined-Functions (UDF)s is presented so that magnetic flow applications can be investigated without software limitations such as discretization scheme, solution setup, and simultaneous use of other advanced modules. Next, the impact of electromagnetic forces on streamlines and isotherms has been studied, and the forces’ area of influence is carefully investigated.Based on the results, the introduced framework has successfully predicted consistent results for three previous studies. Next, by considering a wide range of Rayleigh (Ra), Hartmann (Ha), and Magnetic (Mn) numbers, valuable revelations regarding the force interactions, thermofluidic properties, and force area of influence were revealed. Finally, the situations in which the Kelvin and Lorentz forces are influential are identified based on dimensional analysis