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(2004). Tungsten Heavy Alloy For Defence Applications. Materials Technology: Vol. 19, No. 4, pp. 210-215.

(2003). Ceramic Cutting Tools: Challenges And Prospects. Materials Technology: Vol. 18, No. 3, pp. 151-155.

Aesthetic management of maxillary anteriors provide a challenge to the artistic and technical abilities of a prosthodontist. Metal-free crowns in such cases allows for highly aesthetic solutions to reshape fractured teeth or teeth with other defects. In severely compromised anterior teeth, development of non-metallic post systems has made possible the generation of metal-free ceramic restorations. This article describes a case where all-ceramic crown reinforced with post was utilized to improve the esthetics of the patient.

Rehabilitation of patients with mandibular defect requires a multidisciplinary approach involving a head and neck surgeon, maxillofacial prosthodontist and a reconstructive surgeon. A hemimandibulectomy patient can have many debilitating consequences such as eccentric occlusion, disoriented masticatory cycle, facial disfigurement, distorted speech and salivation problem. The aim of this case report is to describe a technique which combines crown with prosthetic rehabilitation to meet the functional and esthetic requirement of the hemimandibulectomy patients.

Production chains featuring industrial vision are becoming more and more widespread. Those processes are often heavy and applied to high definition images with important frame rate. Powerful calculators are thus needed to follow the ever growing production rate. NVIDIA is currently designing interfaces providing a CUDA (Compute Unified Device Architecture) architecture allowing parallel data computation. This could increase the performance of every operating system using graphical processing units (GPU). Pure Data, thanks to its graphical modular development environment, allows fast prototype developments. Those factors led us to start a research program dedicated to the realizations of image processing modules for Pure Data written in CUDA. So in this we have implemented image blurring algorithm to get familiar with GPGPU.

Scientific Cloud Computing has emerged rapidly in the last few years. Scientific Cloud Computing, which targets high performance communities, has caused a shift over of the scientific applications running on conventional physical infrastructure to a more scalable and flexible virtual infrastructure managed by the cloud providers. Scientific Cloud Computing has brought up a lot of advantages (pay-per-use, resource on-demand, high-availability, flexibility, scalability) over the traditional computing models. Traditional computing models, in order to use scientific applications, require in-house infrastructure (servers, storage etc.) and skill to manage this infrastructure, whereas the Scientific Cloud Computing allows the user to focus on applications without worrying about the infrastructure and installations required. Scientific clouds need proper access mechanisms to improve the adoption of such facilities by scientific communities and enhance the usage of scientific clouds. It is very important to have a proper access mechanism in place for Scientific Clouds so as to improve the adoption of such facilities and enhance the usage of cloud. In this paper, the authors present a Web-Based Job Submission Mechanism for Scientific Cloud Computing, SciInterface. SciInterface provides a graphical user-friendly interface to the users for interacting with the Scientific Cloud and a facility to submit scientific jobs in to the cloud for processing. The prominent features of SciInterface are user privileges mapping, job submission, job monitoring and output logs. The authors, in this paper, discuss the architecture and features of SciInterface, along with the challenges faced during the development.

Background: Fewer studies were conducted on resistance form. This study evaluated the effect of different auxiliary features on inadequate resistance form. Aim: The aim of the study is to evaluate the resistance at 22° taper with reduced occluso-cervical height with different auxiliary features. Methodology: An ivorine tooth was prepared with computer-aided design-computer-aided manufacturing with total occlusal convergence (TOC) of 22°, shoulder finish line 0.9 mm wide, reduced occluso-cervical height, i.e., 2.5 mm, and reduced diameter. The crown preparation was subsequently modified to include interproximal grooves, interproximal boxes, and reduced TOC in the axial wall from 22° to 8° in the cervical 1.5 mm of the axial wall. A total of four groups with ten standardized metal dies were prepared for each design with the computer-aided milling machine. Standardized complete metal crowns using silicon mold were fabricated and cemented on metal dies with glass ionomer cement. The resistance of each specimen was evaluated when force was applied at a 45° angulation to the long axis of the die in a lingual to buccal direction by a universal testing machine. The values were then analyzed using one-way analysis of variance test and post hoc Bonferroni test. Results: The comparison of the mean resistance test values was done among all the groups, and there was a significant (P ≤ 0.001) difference found among the groups. Conclusion: The most effective method of enhancing resistance form preparation is to decrease the TOC of the cervical portion of the prepared axial walls. Two interproximal boxes significantly increased the resistance form. However, two interproximal grooves did not significantly increase the resistance form.

Abstract The importance of obtaining a perfect core of a petroleum reservoir is undisputed. Despite tremendous advances in coring techniques, some basic problems remain as challenging as ever. One of these is the coring of unconsolidated formations. Most side-wall cores result in partially damaged cores, totally damaged cores or no core at all, especially in unconsolidated formations. This proposed technique promises to greatly improve the recovery, quality and longevity of the core, thereby resulting in a much better interpretation. Freezing has long been used to preserve cores on the surface, but never before used in-situ. Here in this technique, part of the formation is frozen before being drilled out. Freeze coring promises to be highly beneficial in percussion side-wall coring, as it increases localised formation strength thus increasing impact resistance. Hence, the chances of recovering the core intact increase significantly. This paper discusses the science of the proposed process, explains the mechanism and puts forward a new design for coring, which will help bring back virgin cores to the surface. Changes in the current techniques are proposed which is backed by experimental work. Overall, this work will help determine petrophysical properties of the reservoir to a much higher accuracy while drilling, thus helping in identifying prolific reservoirs.

Steering and guiding an endoscope in a patient's body has been a challenge for doctors for many years now. Present endoscopic technology allows passive bending of the scope by one or more cables attached to the tip. Bending motions of the tip of a conventional endoscope are controlled from outside the body by wire traction. Therefore, precise operation of the endoscope is difficult in areas of complex shape such as the intestine. Furthermore, patients suffer pain during a procedure with an endoscope. This paper aims at deciphering a solution for the above problems by introducing the concept of active bending of the endoscope with Shape Memory Alloy (SMA) micro-actuators. A Teflon prototype is developed to establish the concept. Many Teflon segments are connected with ball and socket joint and each segment bending is controlled independently which gives high degree of maneuverability to the device. The dexterous device prototype developed is capable of following complex trajectories and can steer tight bends. The same concept of bending can be extended to devices like borescopes, to be used for internal visualization of mechanical systems such as jet engines, turbines, satellites etc. These devices are again expected to follow complex trajectories with tight bends for visualization of specific areas within the highly integrated structure without dismantling.

The prospect of oil production from the Arctic region is attracting attention as the world is becoming more aware about the end of cheap and easy oil. The security and economic risks associated with the expensive and difficult oil remains very high. In deep-water projects, thousands of feet below the sea level, temperatures are near freezing. Combined with the high pressures present at these depths, oil congealment and ice-like hydrate formation is a commonly occurring phenomenon which results into flow restriction. This in turn leads to various production problems and hence substantial financial loss. To counter these problems, Soya slurry is proposed as an anti oil-congealer in this paper. The soybean slurry consists of chemicals like Glycoprotein and unsaturated fats, which act as an anti freeze and suppresses ice nucleation effect. It is introduced in low concentration into the well bore which prevents the well bore fluid from congealing by increasing its thermal hysteresis and acting as an ice nucleation barrier. Even the viscosity of the wellbore fluid substantially reduces resulting in an easy and smooth flow through the pipeline with very less amount of friction experienced between the fluid and tubing. Based on a detailed study, we have inferred that as soybeans are easy available, they have low cost and require simple application techniques, therefore they can provide an appropriate solution to the oil congealment problem. This study will provide fresh physical insight into the phenomenon of anti oil congealer and help in countering the congealment problem in a more effective, economical and environment friendly way.

To compare the temperature changes in the pulpal chamber during fabrication of provisional restorations by direct method. A total of 108 three-unit FPD provisional restorations were fabricated on a study model and divided into three main groups according to the material used for the fabrication of matrix. Group A—Alginate impression index group, Group B—Polyvinylsiloxane putty impression index group, Group C—Vacuum formed template group. Each group comprising of 36 specimens, was subdivided into three subgroups based on the provisional restorative material used: polymethylmethacrylate (subgroup 1), polyethylmethacrylate (subgroup 2), bis-acryl composite resin (subgroup 3). Intrapulpal temperature changes were observed with the help of a thermocouple probe (connected to a digital microprocessor thermometer) inserted into the pulp chamber of an extracted mandibular second molar mounted on a study model, during the fabrication of provisional restorations by direct method. The subgroups mean temperature rise observed in Group A—A1, A2, A3 was 2.6250 ± 0.2491, 1.0500 ± 0.1382, 0.4083 ± 0.1165, respectively. The subgroups mean temperature rise observed in Group B—B1, B2, B3 was 4.6250 ± 0.2454, 3.3750 ± 0.3415, 2.5917 ± 0.2678, respectively. The subgroups mean temperature rise observed in Group C—C1, C2, C3 was 4.7694 ± 1.8361, 3.0611 ± 1.5767, 2.3806 ± 1.5713, respectively. The observations were statistically significant. The intrapulpal temperature rise during fabrication of a provisional restoration depended both on the type of provisional restorative material and the type of matrix used. The clinician should choose carefully the resin and the matrix material while fabricating provisional restorations with direct method.

Parallel coupled microstrip filters are extensively used as band pass filter in microwave communication because they are compact in size, easy to fabricate due to its planar structure. The responses of these filters are satisfactory for narrow bandwidth due to their relatively weak coupling. A severe limitation of the conventionally designed parallel coupled filters is parasitic response at harmonics. In this paper some techniques are discussed to minimize the spurious bands, and also an effective design to suppress these spurious pass bands has been proposed.

The fractal geometries such as Koch curve, Sierpinsky gasket, and Hilbert curve, etc. have been widely studied and applied to design several microwave devices, such as antennas, frequency selective surfaces (FSS), and photonic band gap (PBG) devices. There are several advantages of these fractal devices including reduction of resonant frequencies, smaller size and broadband width. In this paper a critical study has been presented on application of fractal geometry to design the microstrip antenna, microstrip filters and frequency selective surfaces.

Minimally invasive surgery is well-accepted in the society because it involves lesser operative trauma for a patient than an equivalent invasive procedure. It causes less pain and scarring, faster recovery, and reduces the incidence of post-surgical complications. An endoscope is considered as one of the most powerful diagnostic and therapeutic tool for dealing abnormalities inside the body. This article aims at deciphering a solution to the problem of passive bending of conventional endoscopes by introducing a concept of active bending by using shape memory alloy (SMA) micro actuators. The developed prototype has many small segments connected to one another by a ball and socket joint, actuated independently which gives rigidity and high degree of manoeuvrability to the scope. The article proposes an algorithm for traversing the scope inside the body and addresses a very important issue of taking it out without causing any damage to the track. A graphical interface gives the practitioner a number of options to orient the scope [on the basis of three-dimensional (3D) discrete points reached by the tip and segment orientations based on camera image] and simultaneously shows a 3D view of orientation of the full scope.

Purpose: This study was aimed to determine the effect of various tray spacer thickness and subsequent repeated pours on the accuracy and dimensional stability of the impression made from monophasic polyvinyl siloxane material. Materials and Methods: Custom trays with different spacer thickness (2, 4 and 6 mm) were used for making an impression of a master model simulating 3 unit fixed partial denture with monophasic polyvinyl siloxane material. These impressions were poured with die stone and repoured. Distance between the reference points were measured and subjected to statistical analysis. Result: Casts obtained from 1 st , 2 nd and 3 rd pour of the impression in 2, 4 and 6 mm spacer thickness tray have similar dimensional accuracy amongst each other and with the master model except in molar diameter and inter-abutment distances of cast obtained from 6 mm spacer thickness tray. Conclusion: The vertical distance of stone dies were decreased, whereas horizontal distance increased as the thickness of impression material is increased. There were statistically non-significant changes occurring among the repeated pours in 2, 4 and 6 mm spacer thickness. Clinical Implication: 2 and 4 mm spacer thickness are acceptable for making an impression for three unit fixed partial denture with monophasic polyvinyl siloxane material and it was not affected by two subsequent (1 st and 2 nd ) repeated pours.

Predictable retrievability of cement retained prosthesis has been a major clinical concern. This article presents review of techniques used for implant prosthesis removal without any potential damage to abutments and implants.

Nervous excitement. That was how I felt the night before my life as a ‘real GP’ began. 3 August 2010 was my final day as a registrar and I remember counting down the last days of ‘training’ fluctuating between feelings of fear and the happy realisation that what I had worked towards for 10 years was imminent. Of course ‘training’ had not finished and I was actually embarking upon the steepest learning curve since I started as a junior doctor back in 2005. The transition has proved to be challenging, rewarding, and at times slightly unnerving, and I look back on it with a quiet sense of pride. Day 1. I turn up in my new suit (to one of the surgeries where I had been ‘the trainee’ just a day before) and before I have a chance to brew a coffee, the first call …