This review article compiles the characteristics of resin based dental composites and an effort is made to point out their future perspectives. Recent research studies along with few earlier articles were studied to compile the synthesis schemes of commonly used monomers, their characteristics in terms of their physical, mechanical and polymerization process with selectivity towards the input parameters of polymerization process. This review covers surface modification processes of various filler particles using silanes, wear behaviour, antimicrobial behaviour along with its testing procedures to develop the fundamental knowledge of various characteristics of resin based composites. In the end of this review, possible areas of further interests are pointed out on the basis of literature review on resin based dental materials.

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We present a simple sealing method to fabricate nanofluidic channels, where plasma treated polysilsesquioxane (PSQ) thin film on a rigid support is used to bond to a hydrophilic glass surface permanently at room temperature. This method shows precise dimension control below 10 nm with easy experimental setup. Using this method, one dimensional confined shallow nanochannels with a depth as small as 8 nm and an aspect ratio of <4 x 10(-5), two dimensional confined nanochannel arrays, and integrated nano/microchannel devices with a micro-to-nano interface have been demonstrated. Smooth transfer of DNA fragments from microchannel to nanochannel through the interface area was observed.

A new concept solution for improving blast survivability of the light tactical military vehicles is proposed and critically assessed using computational engineering methods and tools. The solution is inspired by the principle of operation of the rocket-engine nozzles, in general and the so called "pulse-detonation" rocket-engines, in particular. The proposed concept utilizes side vent channels attached to the V-shaped vehicle underbody whose geometry is optimized with respect to the attainment of the maximum downward thrust on the vehicle. In the course of the channel design optimization, analytical and computational analyses of supersonic flow (analogous to the one often

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Purpose -The recently proposed concept solution for improving blast-survivability of the light tactical military vehicles is critically assessed using combined finite-element/discrete-particle computational methods and tools. The purpose of this paper is to propose a concept that involves the use of side-vent-channels attached to the V-shaped vehicle underbody. Since the solution does not connect the bottom and the roof or pass through the cabin of a light tactical vehicle, this solution is not expected to: first, reduce the available cabin space; second, interfere with the vehicle occupants' ability to scout the surroundings; and third, compromise the vehicle's off-road structural durability/reliability. Furthermore, the concept solution attempts to exploit ideas and principles of operation of the so-called "pulse detonation" rocket engines in order to create a downward thrust on the targeted vehicle. Design/methodology/approach -To maximize the downward thrust effects and minimize the extent of vehicle upward movement, standard engineering-optimization methods and tools are employed for the design of side-vent-channels. Findings -The results obtained confirmed the beneficial effects of the side-vent-channels in reducing the blast momentum, although the extent of these effects is relatively small (3-4 percent). Originality/value -To the authors' knowledge, the present work is the first public-domain report of the side-vent-channel blast-mitigation concept.

Functionalized multiwalled carbon nanotubes (a-MWCNTs) and non-functionalized MWCNTs were melt mixed with polycarbonate polymer by utilizing twin screw micro compounder having a back flow channel to obtain nanocomposites with varying composition from 0.5 to 10 wt% MWCNT and 2 wt% a-MWCNT. Mechanical properties of composite samples were studied using dynamic mechanical analyzer, flexural and tensile tests. Both DMA and flexural and tensile tests suggest formation of continuous network of CNT-polymer that is supported by measured storage modulus for different loading of MWCNT and a-MWCNT. The composite sample showed lower glass transition temperature (T g ) as compared to pure PC. Effect of functionalization of MWCNTs on T g of its of polycarbonate composites is studied and showed higher T g depression in functionalized MWCNTs compared to non functionalized MWCNTs based composites over pure polycarbonate. In DMA, lowering of height of tan delta peak indicates that polymer in composite material participating in T g was reduced along with loading of MWCNT, consistent with immobilization of polymer material present at the CNT interface.Effect of functionalization on morphology was investigated using scanning electron microscope and confirms the better interaction in case of a-MWCNTs compare to MWCNTs based composites. Further, Raman spectroscopic analysis indicates higher interaction between a-MWCNT and PC matrix as compared to as synthesized MWCNT.

SSDs could be attributed as a risk factor in a fifth of the cases of stillbirths. The number needed to harm for the use of SSDs in causing adverse effect of stillbirths was 5, suggesting thereby that for every five mothers exposed to SSDs, one would have stillbirth. Greater efforts are required to inform people about the harmful effects of SSD consumption during pregnancy.