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The condition known as oral submucous fibrosis (OSMF), which is mostly brought on by the chewing of areca nuts, manifests as a burning sensation, paleness of the oral mucosa, a palpable fibrous band, and restricted mouth opening. The stages of OSMF, which are based on clinical and pathological grading, determine the appropriate course of treatment. For trismus alleviation and repair surgery for any malignant transformation, patients with OSMF need treatment. A 58-year-old woman who had a limited mouth opening and complained about pain as well as a burning sensation when eating was seen. The patient had oral physiotherapy in addition to intralesional steroids (Dexamethasone 4 mg and Hyaluronidase 1500 I.U.). The effects of chewing areca nuts and their propensity to cause cancer have been explained to the patient

Carbon fibre reinforced CVI-SiC matrix (Cf/SiC) composite is well known for its superior properties such as low density, high specific modulus, high fracture toughness, and high temperature mechanical properties. In the present work, 2.5-Directional Cf/SiC composites with (PyC/SiC) n=4 multilayer interface having two different thicknesses with a density of ~2.1 g cm-3 are prepared through isobaric isothermal chemical vapour infiltration technique. High temperature tensile properties of the prepared composites with and without Si-B-C seal coating are studied and the results are presented. Samples prepared without seal coat exhibited a KICof ~ 30 MPa m1/2, and tensile strength of ≥200 MPa at room temperature. Si-B-C seal coated Cf/SiC composites has shown significant increase (28%) in high temperature tensile strength at 1200 °C and 1500 °C respectively compared to uncoated composites. Microstructural observations, XRD, and XPS studies support the observed thermomechanical behaviour of these composites at 1200 °C and 1500 °C.

Continuous carbon fiber (Cf) reinforced silicon carbide (SiC) matrix composite (Cf/SiC) was processed through hot pressing (HP) using polycarbosilane (PCS) in matrix and polysilazane in interphase regions as polymer binders. HP experiments were conducted at 4 MPa, 1200 °C and 1 h; followed by PCS polymer impregnation and pyrolysis (PIP) at 1200 °C under vacuum. The BN/SiC-Si3N4 interphase formed on the Cf cloth during BN dispersed polysilazane polymer coating and pyrolysis. The influence of PCS quantity during HP experiments on Cf/SiC composites was studied. Results suggest that sintering of SiC matrix in Cf/SiC composite improves by increasing PCS content during HP; however, high PCS content increases the liquidity of SiC-PCS mixture to flow out of the composite structure. The Cf/SiC composites with relative density ranging from 79 to 83% and flexural strength from 67 to 138 MPa was achieved.

Hydrothermal method was employed for the synthesis of pure Cobalt ferrite and Nickel doped Cobalt ferrite nanoparticles. The crystallinity, morphological and the electrochemical investigation of the prepared samples were studied using X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM), FT-IR and Cyclic voltammetry (CV) study analysis. The cubic spinel crystal structure was revealed by the XRD pattern. The average crystallite size for the pure cobalt ferrite and the nickel doped cobalt ferrite doped samples were 20 nm and 25 nm respectively. The lattice constant of the pure and the doped samples were 8.29 A and 8.36 A respectively. SEM analysis revealed the presence of nanoclusters. The EDS patterns confirmed the presence of the elements Ni, Co, Fe and O without any impurity. The infra-red spectra showed the features of higher and lower energy bands corresponding to tetrahedral (T-band) and the presence of octahedral (O-band) complexes confirmed the creation of spinel ferrites. The electrochemical behavior of the prepared nanoparticles was investigated through Cyclic Voltammetry (CV) study analysis using 2 M of KOH electrolyte solution. The potential window was limited as 0 V to 0.6 V at various scan rates 10, 30, 50, 80 and 100 mV/s. Cyclic Voltammetry study revealed that the Nickel dopant increased the specific capacitance than the pure Cobalt ferrite. The specific capacitance of the pure cobalt ferrite and the nickel doped cobalt ferrite samples were obtained as 517 F/g and 561 F/g respectively.

Magnesium (Mg)-titanium aluminum carbide (Ti3AlC2) composites were produced by hot pressing (HP) at 0.15 to 1 MPa, 923 K (650 °C) for 30 minutes; Mg-Ti3AlC2 (10 to 30 vol pct) composite produced at 0.15 MPa, 923 K (650 °C) for 30 minutes exhibited 95 to 99 pct relative density (RD), while Mg-40Ti3AlC2 produced at 1 MPa, 923 K (650 °C) for 30 minutes exhibited full density. Improved densification results are mainly due to the flow of liquid Mg between the Ti3AlC2 particles. The monolithic Mg processed at 5 MPa, 873 K (600 °C) for 5 minutes also exhibited full density. Further, Mg-Ti3AlC2 composites produced at low pressure (1 MPa) exhibited maximum density as compared to other research works. Monolithic Mg exhibited a microhardness of 62 ± 8 HV0.5. Besides, as the Ti3AlC2 content was varied from 10 to 40 vol pct, the microhardness of Mg-Ti3AlC2 composites increased from 62 ± 5 to 158 ± 11 HV0.5. The compressive strength of Mg-Ti3AlC2 (10 to 40 vol pct) composite at room temperature (RT) was in the range of 180 ± 10 to 617 ± 13 MPa. The compressive strengths of Mg-Ti3AlC2 (30 and 40 vol pct) composites at 473 K (200 °C) were 366 ± 20 and 480 ± 71 MPa, respectively. The flexural strength of Mg-Ti3AlC2 composites (20 to 40 vol pct) was determined to be in the range of 335 ± 12 to 513 ± 3 MPa.

An experimental study was undertaken to understand the tensile behavior of metal–ceramic composite joint with bolted configuration. Nickel based super alloy (GTM-Su-263) and SiCf/SiC composite were the material systems with an aerospace grade MJ6 bolt of GTM-Su-718. This bolted assembly was pulled at temperatures 25, 600 and 750 °C which were likely to be experienced in a typical aero engine. In case of metal–ceramic composite joint, the net tensile stress decreased from 110 to 88 MPa with increase in temperature from 25 to 600 °C. Similarly, the bearing stress reduced from 146 to 118 MPa. In all the metal–ceramic composite joints, the fracture initiated at the hole edge experienced the maximum tensile stresses. With further increase in temperature, reduction in the net tensile and bearing strength was significant and was attributed to the oxidation of the interface between the fiber and matrix. SEM studies clearly suggested that debonding and fiber pullout resulted in inferior tensile strength properties at elevated temperatures.

The main objective of this work is to compare the friction stir welding with plasma arc welding processes using dissimilar materials. The materials used AA 8011 and AA 6061.The factors compared in this process are the weld quality, different welding feed and rotation speed. The effects of welding processes on the impact test and micro hardness behaviour were studied. Morphological analysis was carried out using SEM analysis. Taguchi’s, DOE method and ANOVA is done to find the parameters that have highest influence on weld strength. The results show that the FSW joints exhibit superior tensile and fatigue, impact test, and micro hardness properties compared to plasma arc welding. This is mainly due to the presence of mechanical properties are superior to plasma arc welding. Keywords: Friction stir welding, SEM, AA 8011, AA 6061, plasma arc welding, ANOVA, and DOE

This paper presents a case study of DDR3 interface timing jitter of a DDR subsystem on an evaluation module. The total jitter was separated into various Signal Integrity (SI) and Power Integrity (PI) effects, including signal crosstalk, impedance discontinuities, simultaneous switching noise (SSN), and inter-symbol interference (ISI). Good correlation was achieved between the simulation environment and silicon measurements. The paper also discusses how the study helped guide the package selection for a family of SoC designs.

Three dimensional non-Interlaced carbon fibre reinforced silicon carbide (3-D-Cf/SiC) composites with pyrocarbon interphase were fabricated using isothermal chemical vapor infiltration (ICVI) combined with polymer impregnation pyrolysis (PIP) process. Polysilazane (PSZ) is used as a preceramic polymer to obtain silicon carbide matrix. Thermo gravimetric analysis (TGA), Infrared spectroscopic analysis (IR) and X-ray diffraction (XRD) analysis were carried out on PSZ pyrolysed at different temperatures to understand the pyrolysis and obtaining the optimum pyrolysing condition to yield β-SiC phase. The density of the composites was 1.94 g cm-3 after the 3-D carbon preform was SiC infiltrated for 280 h with one intermediate polysilazane pre-ceramic PIP process. Mechanical properties of the composite materials were investigated under tensile, flexural, shear and impact loading. The values of tensile strength were 200 MPa at room temperature (RT) and 195 MPa at 500°C in air. The average RT flexural strength was 243 MPa. The lower flexural strength of these composites is because of the porosity. The fracture toughness obtained from single edge notched beam (SENB) technique was 39 MPa.m1/2. The work of fracture obtained from the load-displacement curve of SENB test was 22.8 kJ.m-2. The composites exhibited excellent impact resistance and the dynamic fracture toughness of 44.8 kJ.m-2 is achieved as determined from instrumented Charpy impact test. The shear strength of the composite was 93 MPa, which is significantly higher compared 2-D Cf/SiC composites. Microstructure evaluation of fracture surfaces revealed the signatures of fracture processes and showed good support for the higher toughness obtained., {"references":["G. O. Young, \"Synthetic structure of industrial plastics (Book style with\npaper title and editor),\" in Plastics, 2nd ed. vol. 3, J. Peters, Ed. 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Current insole systems often require costly equipment and additionally exhibit large form factors and are often of limited in their range of activities that they can measure. These problems can be addressed if spatial resolution in the insole is sacrificed. In this study, a low-resolution smart insole system was designed and developed for the real-time determination of several gait parameters. Tekscan flexi-force sensors were selected to meet the required sensor properties: durability, sensitivity, precision and sensing-area. F-Scan system and PressureStat film were used to accurately position the sensors on the insole to capture the heel and metatarsals. Sensor data from the insole were acquired and wirelessly transmitted to a PC using an Arduino microcontroller with XBee radio. The insole was calibrated for pressure with a Kistler force plate system. Captured ground reaction forces were analyzed for symmetry in external work and gait phase transitions in unilateral lower-limb amputees on both anatomical and prosthetic feet in multiple ambulation tasks, including level-ground and ramp walking. The developed wireless instrumented insole system has the advantages of broadcasting real-time insole forces with minimal computational resources as well as being durable and portable.

SiCf/SiC composites are class of high temperature structural materials being developed for use in nuclear fusion and fission reactor systems because of their superior high temperature mechanical properties, low radiation damage and low induced radioactivity. Two types of 2D SiCf/SiC composites were made through isothermal and isobaric chemical vapor infiltration process using eight harness satin-woven ceramic-grades Nicalon� fibers with boron nitride (BN) interface, namely: one with lower interface thickness and a second type with higher interface thickness. The BN interface was applied to the fiber prior to SiC matrix addition to modify the interfacial bond strength leading to better toughness and improved oxidation resistance. The density achieved was around 2.6 g/cc. The composite specimens were subjected to thermal cycling treatment using an in-house furnace. The mechanical properties such as tensile strength, fracture toughness and interfacial bond strength were also studied for all the composites before and after thermal cycling. It is seen from the results that both composites withstood thermal shocks and thermal cycling treatment. It was also concluded from the present work that good balance between load transfer and crack arresting was established. � 2013 Elsevier B.V. All rights reserved.

Background and Objectives: Chloramphenicol was considered the anti-microbial gold standard for typhoid treatment but, following the increasing worldwide frequency of antibiotic resistance, ciprofloxacin has been the mainstay of therapy since 1980. Recent studies have shown a shifting of susceptibility to conventional drugs like chloramphenicol, ampicillin and cotrimoxazole. The primary objective of the study was to evaluate the in vitro activity of chloramphenicol and other first-line drugs in comparison with cephalosporins and quinolones. Materials and Methods: Fifty isolates of Salmonella obtained from blood culture were subjected to serotyping at the Central Research Institute, Kasauli. Phage typing and biotyping was performed at the National Phage Typing Centre, New Delhi. Antibiotic sensitivity testing was carried out for 10 drugs by the Kirby-Bauer disc diffusion method and minimum inhibitory concentration by broth microdilution for nalidixic acid, chloramphenicol, ciprofloxacin, ceftriaxone, cefixime and ofloxacin. Multi-drug-resistant (MDR) strains were checked for plasmid. Results: In the present study, 70 and 30% of the isolates were Salmonella enterica serovar typhi and paratyphi A, respectively. They were highly sensitive to chloramphenicol (86%), ampicillin (84%) and cotrimoxazole (88%). Highest sensitivity was seen for cephalosporins, followed by quinolones. Seventeen/21 (81%) and 100% of the Salmonella enterica serovar typhi strains belonged to E1 phage type and biotype 1, respectively. Antibiogram showed 2% of the strains to be sensitive to all the drugs tested and 12% were MDR and showed the presence of plasmids. Conclusion: The study indicates reemergence of chloramphenicol-susceptible Salmonella enterica serovar typhi and paratyphi A isolates, a significant decline in MDR strains and high resistance to nalidixic acid. E1 phage type and biotype 1 are found to be most prevalent in Chennai, India.

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