Head injury mechanisms and the concept of preventive management: a review and critical synthesis

Recent advances in head injury research have produced a plethora of useful data coupled with a paucity of conceptual integration across the four ways in which this research is pursued. These research orientations are the epidemiological, biomechanical, basic neuroscientific, and clinicopathologic/therapeutic (including rehabilitation). This overview of the history and current state of the art assumes that biomechanics is the basic science of causation in head injury research and when fully integrated with its counterparts, physiology and pathology, it can serve to overcome our conceptual handicaps. A paradigm integrating biomechanics; into the sequence of preventive, protective, acute therapeutic, and rehabilitative interventions will be described as the concept of preventive management. From this we derive the hypothesized claim that the exact biomechanics and the physiopathologic response at the time of injury (at the macroscopic and microscopic levels) determine the sequence of so-called secondary effects that are conceived as the inexorable delayed manifestations of the primary events and concomitant boundary conditions. Knowledge of these events will enable accurate predictions of the natural history and outcome of head injuries from observations carried out in the early acute phase. Examples to test this claim will be given with particular reference to the two types of traumatic brain injury (TBI) phenomenologically associated with disturbances of consciousness, the onset of which can be either immediate or delayed. The current economics and availability of computational power provide a significant opportunity for the development of selected experimental, physical, and simulated models of head injury on the basis of which the complex neurovascular and nonneural cellular and fluid elements of the nervous system may be accurately modeled. This approach will significantly improve the efficiency and quality of the essential biological and clinical observations and model experiments required to validate the theoretical methods and their predictions.     

Influence of Nano Silica on Mechanical and Durability Characteristic of Mortar made by Partial Replacement of Natural Fine Aggregate with Recycled Fine Aggregate

Silicon - To implement sustainability concepts in the construction industry, the possibility of utilizing the recycled fine aggregate obtained from the crushing of coarse aggregate debris of...     

Alkylation of naphthalene with alcohols over mesoporous MCM-41

Mesoporous MCM-41 is found to promote alkylation of naphthalene by alcohols. In addition to the preferred branched side chain productsn-alkylated product is also observed in the case of propylation of naphthalene.     

Lightweight graphics instrumentation for game state-specific power management in Android

Battery life is a major concern on portable devices like smartphones and tablet PCs. On these devices, games constitute the class of most popular applications and are at the same time highly compute-intensive. Every game consists of several states like the loading, main menu and the gaming state. Each of those states has its own workload characteristics, e.g., the loading phase is likely to be memory bound and the main menu state is less interactive than the gaming state. We propose an interception technique that allows to profile the game and detect its current state based on the game’s communication with the underlying OS. Current power management governors are unaware of the running applications and scale the processor’s voltage and frequency merely based on the system’s utilization. We provide the game’s state information and workload profile to our governor which selects the processing frequency such that the desired frame rate of the current state is ensured. This leads to an optimal choice of processing frequencies and thereby significantly reduces power consumption. We have implemented the scheme on an Android-based Samsung Galaxy Nexus smartphone using popular games like Jetpack Joyride and Temple Run. We reduced the CPU’s power consumption by up to 43.2 % compared to the Android interactive governor without impacting the gaming experience. Motivated by these results we propose a power management API that would allow game developers to significantly reduce the power consumption of their game using simple API calls.     

Studies on engineering properties of PVC–PMMA semi‐interpenetrating polymer networks

Semi1 and semi2 interpenetrating polymer networks (IPNs) of PVC and in situ formed PMMA have been synthesized using diallyl phthalate and ethylene glycol dimethacrylate as the crosslinkers of PVC and PMMA, respectively. These two types of IPNs have been compared w.r.t their physical, mechanical, and thermal properties and an endeavor has been made to find a correlation of these properties with the morphology generated in these systems. The semi1 IPNs displayed a decrease in their mechanical parameters and the physical properties as well, while in contrast, the semi2 IPNs exhibited a marginal increase in the corresponding values after an initial drop upto about 15% of crosslinked PMMA incorporation when compared to the crosslinked PVC in the case of semi1 IPN and linear PVC in the case of semi2 IPN. The various samples of semi1 and semi2 IPNs showed a two‐stage degradation typical of PVC, while confirming the increased stability with the samples having higher percentages of PMMA. The influence of crosslinking of the major matrix in semi1 IPN was almost counterbalanced by the influence of crosslinking in the dispersed PMMA phase in the case of semi2 IPN. The softening characteristics as detected by the extent of penetration of the probe, as has been detected by thermomechanical analysis, are in conformity with their mechanicals. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1725–1735, 2005     

Miscibility and fracture toughness of thermoplastic polyurethane/poly(vinyl chloride)/nitrile rubber ternary blends with special reference to the blend composition

Ternary blends of thermoplastic polyurethane and a poly(vinyl chloride)/nitrile rubber blend were investigated in this work. The blends, with weight ratios of 100/0, 80/20, 40/60, 60/40, 80/20, and 0/100, were prepared via melt blending. Dynamic mechanical analysis showed that the blends with ratios of 20/80 and 80/20 were miscible, whereas the 40/60 and 60/40 blends were partially miscible. IR spectroscopy studies showed shifts in the peaks due to specific interactions in the blends. The blends showed degradation behavior between the blend components. The fracture toughness was investigated with the J‐integral by the locus method; the components and the miscible blends had good fracture toughness, whereas the other blends had lower toughness. Similar behavior was observed for the tensile properties. Scanning electron microscopy studies showed the morphological variations in the blends. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1763–1770, 2005     

Performance evaluation of saponin over other organic acid and tap water for removal of chromium in tannery sludge by electrokinetic enhancement

The performance of Saponin over different electrolyte-mediated electrokinetic (EK) process for removal of Cr(III) from tannery sludge was assessed. Saponin exhibited maximum Cr(III) removal efficiency, i.e. 67.6–80.75% as compared to other groups of processing fluids. The possible mechanistic approach for the highest removal efficiency of saponin over other electrolytes may be attributed to synchronized effect of micelle formation and subsequent complexation and sorption of chromium ions. The highest electroosmotic flow rate of saponin indicated low electroosmotic resistance during EK process, which validates the observed trend. Therefore, saponin can be considered as a promising electrolyte for EK treatment of tannery sludge.

Abbreviation: CA: Citric acid; LA: lactic acid; OA: oxalic acid; BOD: biochemical oxygen demand; COD: chemical oxygen demand; EK: electokinetic.     

一种高效又经济的混炼方法——在配方中添加塑解剂Acimel

一种高效又经济的混炼方法———在配方中添加塑解剂ＡｃｉｍｅｌＤｒ．ＣｈａｋｒａｂｏｒｔｙＳ（ＩＣＩＩｎｄｉａＬｉｍｉｔｅｄ）橡胶是一种弹性体，相对分子质量比较高，在加工温度下有较高的粘度。若不加入配合剂，橡胶本身是无法使用的。由于要加入的配合剂大多...     

Measurement of AC conductivity and dielectric properties of flexible conductive styrene–butadiene rubber‐carbon black composites

Flexible conductive polymer composites were prepared using styrene–butadiene rubber (SBR) as a matrix and conductive carbon black as filler. The filler loading was varied from 10 to 60 phr. The effect of frequency, filler loading, temperature, and applied pressure on the AC conductivity, permittivity, and loss factor of the composites was studied. The AC conductivity of low and high loaded composites was found to be frequency dependent and independent respectively. The permittivity and the loss factor were continuously decreasing with increasing frequency. The increase in filler loading increased the AC conductivity, dielectric constant, and loss factor of the composites. Increase in temperature imposed increase in conductivity and permittivity of the composites. With increasing applied pressure the properties showed exponential increase. The effect of time under a constant compressive stress was studied and dielectric relaxation times were evaluated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 986–995, 2007     

Epoxy/poly(methyl methacrylate) interpenetrating polymer networks—morphology,mechanical and thermal properties

Full and semi-IPNs were prepared from epoxy and poly methyl methacrylate (PMMA), by the sequential mode of synthesis and were characterized by measurements of ultimate tensile strength (UTS), elongation at break, modulus, and toughness. Aromatic polyamine adducts and ethylene glycol dimethacrylate were used as the crosslinkers for epoxy and comonomer/crosslinker for methyl methacrylate monomer, respectively. Higher UTS and modulus of the semi-IPNs over full IPNs were attributed to the higher probability of interpenetration. The weight retention in the thermal decomposition of the IPNs and semi-IPNs were higher than the epoxy homopolymer. This enhancement was presumably related to the presence of the unzipped methyl methacrylate monomer which acted as radical scavangers in the epoxy degradation. © 1994 John Wiley & Sons, Inc.