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Background: During orthodontic tooth movement friction occurs at the bracket wire interface. Out of the total force applied to the tooth movement, some of it is dissipated as friction, and the remainder is transferred to the supporting structures of the tooth to mediate tooth movement. However many factors affect friction, and method of arch wire ligation being an important contributing factor. Hence, this study was carried out to evaluate the effects of different ligature materials on friction in sliding mechanics and to compare the effect of environment (dry and wet) on friction produced in sliding mechanics. Materials and Methods: The evaluation of friction between the bracket and the archwire consisted of a simulated half arch fixed appliance with archwire ligated in a vertical position. Four 0.022" maxillary stainless steel premolar brackets having a - 0° torque and 0° angulation were aligned with a 0.019" × 0.025" stainless steel arch wire onto a rigid Plexiglass sheet. The movable test bracket was fitted with a 10 mm long, 0.045" thick stainless steel power arm on the bonding surface. Testing was performed on a Hounsfield material testing machine. A total of 100 g weight was suspended from the power arm and the load needed to move the bracket over the distance of not <4 mm across the central span was recorded separately. Fifteen representative readings were taken with one reading per test sample. Results: The results showed that the mean frictional force of different groups in dry and wet state was statistically significantly different. The mean frictional force in a dry state was statistically significantly higher than wet state in elastomeric group. Conclusion: The type of ligation material and environment significantly affected the degree of friction generated during sliding mechanics. Teflon coated stainless steel ligatures produced the least friction among the materials tested in both dry and wet conditions and there was no significant effect on friction in this group caused due to lubrication. [ABSTRACT FROM AUTHOR]

Brief Background: Class II division 1 malocclusion is the most common malocclusion seen in day-to-day practice. This paper describes the use of myofunctional appliance to treat such class II cases at an early age and avoid extractions which may be required at an adult age. Materials and Methods: The case of skeletal class II malocclusion was treated using the bionator appliance. The appliance was worn for 11 months and the mandible was brought forward to a class I skeletal and dental relationship. Final finishing and detailing of occlusion was carried out with 0.022" MBT pre-adjusted edgewise appliance. Discussion: Discussion focuses on the use of myofunctional appliances to modulate growth, advantages of intercepting the malocclusion at an early age by taking advantage of growth spurts thereby improving the profile and in many cases avoiding extractions. Summary and Conclusions: The use of functional jaw orthopaedics, at the correct time during growth can result in class II div 1 patients getting good functional occlusion, straight lateral profile and beautiful smile. Whenever required, it can be followed by comprehensive fixed appliance treatment for detailing of occlusion. [ABSTRACT FROM AUTHOR]

India first adopted minimum energy performance standards (MEPS) in the year 2006. Today, there are standards for a wide range of domestic, commercial and selected industrial products. Concerning about the integrity of the energy information labeling and MEPS, Bureau of Energy Efficiency (BEE) has launched check testing scheme and started to conduct check testing of these products for compliance of standards at the laboratories in India. These labs have been technically competent and accredited by National Accreditation for Testing and Calibration Laboratories (NABL). Government of India has authorized NABL as the sole accreditation body for Testing and Calibration Laboratories. This paper presents the application of Interpretive Structural Modeling (ISM) as a potential decision making tool for identify the knowledge management variables affecting the check testing scheme. The objective of applying the ISM in the area of check testing covered under Standards and Labeling (S&L) Progarmme to analyze the driving power and dependence powers of the variables using MIC MAC analysis based on their nature and characteristics. The MIC MAC analysis has strong influence in clustering the variables for further application to assess the performance of the check testing labs in India. [ABSTRACT FROM AUTHOR]

Bone defects above critical size do not heal completely by itself and thus represent major clinical challenge to reconstructive surgery. Numerous bone substitutes have already been used to promote bone regeneration, however their use, particularly for critical-sized bone defects along with their long term in vivo safety and efficacy remains a concern. The present study was designed to obtain a complete healing of critical-size defect made in the proximal tibia of New Zealand White rabbit, using nano-hydroxyapatite/gelatin and chemically carboxymethylated chitin (n-HA/gel/CMC) scaffold construct. The bone-implant interfaces and defect site healing was evaluated for a period up to 25 weeks using radiography, micro-computed tomography, fluorescence labeling, and histology and compared with respective SHAM (empty contra lateral control). The viscoelastic porous scaffold construct allows easy surgical insertion and post-operatively facilitate oxygenation and angiogenesis. Radiography of defect treated with scaffold construct suggested expedited healing at defect edges and within the defect site, unlike confined healing at edges of the SHAM sites. The architecture indices analyzed by micro-computed tomography showed a significant increase in percentage of bone volume fraction, resulted in reconciled cortico-trabecular bone formation at n-HA/gel/CMC constructs treated site (15.2% to 52.7%) when compared with respective SHAM (10.2% to 31.8%). Histological examination and fluorescence labeling revealed that the uniformly interconnected porous surface of scaffold construct enhanced osteoblasts’ activity and mineralization. These preclinical data suggest that, n-HA/gel/CMC construct exhibit stimulation of bone's innate regenerative capacity, thus underscoring their use in guided bone regeneration. [ABSTRACT FROM AUTHOR]

In this article, we present an accurate and easy to use augmented reality (AR) application for mobile devices. In addition, we show how to better organize and track artifacts using augmented reality for museum employees using both the mobile device and a 3D graphic model of the museum in a PC server. The AR mobile application can connect to the server, which maintains the status of artifacts including its 3D location and respective room location. The system relies on 3D measurements of the rooms in the museum as well as coordinates of the artifacts and reference markers in the respective rooms. The measured coordinates of the artifacts through the AR mobile application are stored in the server and displayed at the corresponding location of the 3D rendered representation of the room. The mobile application allows museum managers to add, remove, or modify artifacts' locations simply by touching the desired location on the touch screen showing live video with AR overlay. Therefore, the accuracy of the touch screen-based artifact positioning is very important. The accuracy of the proposed technique is validated by evaluating angular error measurements with respect to horizontal and vertical field of views that are 60 ∘ and 47 ∘ , respectively. The worst-case angular errors in our test environment exhibited 0.60 ∘ for horizontal and 0.29 ∘ for vertical, which is calculated to be well within the error due to touch screen sensing accuracy. [ABSTRACT FROM AUTHOR]

Salmonella enterica serovar Kentucky has become the most frequently isolated serovar from poultry in the United States over the past decade. Despite its prevalence in poultry, it causes few human illnesses in the United States. The dominance of S. Kentucky in poultry does not appear to be due to single introduction of a clonal strain, and its reduced virulence appears to correlate with the absence of virulence genes grvA, sseI, sopE, and sodC1. S. Kentucky's prevalence in poultry is possibly attributable to its metabolic adaptation to the chicken cecum. While there were no difference in the growth rate of S. Kentucky and S. Typhimurium grown microaerophilically in cecal contents, S. Kentucky persisted longer when chickens were coinfected with S. Typhimurium. The in vivo advantage that S. Kentucky has over S. Typhimurium appears to be due to differential regulation of core Salmonella genes via the stationary-phase sigma factor rpoS. Microarray analysis of Salmonella grown in cecal contents in vitro identified several metabolic genes and motility and adherence genes that are differentially activated in S. Kentucky. The contributions of four of these operons (mgl, prp, nar, and csg) to Salmonella colonization in chickens were assessed. Deletion of mgl and csg reduced S. Kentucky persistence in competition studies in chickens infected with wild-type or mutant strains. Subtle mutations affecting differential regulation of core Salmonella genes appear to be important in Salmonella's adaptation to its animal host and especially for S. Kentucky's emergence as the dominant serovar in poultry. [ABSTRACT FROM AUTHOR]