Proton-gated Ca(2+)-permeable TRP channels damage myelin in conditions mimicking ischaemia

The myelin sheaths wrapped around axons by oligodendrocytes are crucial for brain function. In ischaemia myelin is damaged in a Ca(2+)-dependent manner, abolishing action potential propagation. This has been attributed to glutamate release activating Ca(2+)-permeable N-methyl-d-aspartate (NMDA) receptors. Surprisingly, we now show that NMDA does not raise the intracellular Ca(2+) concentration ([Ca(2+)]i) in mature oligodendrocytes and that, although ischaemia evokes a glutamate-triggered membrane current, this is generated by a rise of extracellular [K(+)] and decrease of membrane K(+) conductance. Nevertheless, ischaemia raises oligodendrocyte [Ca(2+)]i, [Mg(2+)]i and [H(+)]i, and buffering intracellular pH reduces the [Ca(2+)]i and [Mg(2+)]i increases, showing that these are evoked by the rise of [H(+)]i. The H(+)-gated [Ca(2+)]i elevation is mediated by channels with characteristics of TRPA1, being inhibited by ruthenium red, isopentenyl pyrophosphate, HC-030031, A967079 or TRPA1 knockout. TRPA1 block reduces myelin damage in ischaemia. These data suggest that TRPA1-containing ion channels could be a therapeutic target in white matter ischaemia

Metamorphosis of Subarachnoid Hemorrhage Research: from Delayed Vasospasm to Early Brain Injury

Delayed vasospasm that develops 3–7 days after aneurysmal subarachnoid hemorrhage (SAH) has traditionally been considered the most important determinant of delayed ischemic injury and poor outcome. Consequently, most therapies against delayed ischemic injury are directed towards reducing the incidence of vasospasm. The clinical trials based on this strategy, however, have so far claimed limited success; the incidence of vasospasm is reduced without reduction in delayed ischemic injury or improvement in the long-term outcome. This fact has shifted research interest to the early brain injury (first 72 h) evoked by SAH. In recent years, several pathological mechanisms that activate within minutes after the initial bleed and lead to early brain injury are identified. In addition, it is found that many of these mechanisms evolve with time and participate in the pathogenesis of delayed ischemic injury and poor outcome. Therefore, a therapy or therapies focused on these early mechanisms may not only prevent the early brain injury but may also help reduce the intensity of later developing neurological complications. This manuscript reviews the pathological mechanisms of early brain injury after SAH and summarizes the status of current therapies

The surveying of soil and groundwater pollution in a petroleum refinery and the potential of bioremediation for oil decontamination

Published online: 30 Oct 2013Soil contamination with crude oil is an important worldwide issue and the remediation of oil contaminated soils, sediments and groundwater is a major environmental challenge. In the target area of this survey, which is a petroleum refinery near Tehran, soil and groundwater pollution, and its source, contaminated area, and distribution of pollution were studied by means of different measurements. Oil content and volatile organic compounds were measured to determine soil and groundwater contamination. The investigations showed that the contamination of soil which is mainly silt and clay has reached to the groundwater which is around 20 m underground and formed an oily layer mainly containing gasoline, kerosene, and gas oil with different thicknesses in the whole area. The free oil existing over the groundwater table could be removed by physical ways such as pump and treat method but decontamination of soil is more complex. Due to long-lasting contamination of the field, the existence of accumulated indigenous microorganisms and the probable ability of them to effectively biodegrade pollutants by man-assisted interventions are expected. In this survey in order to clarify the contamination problem, some experiments have been done on the region soil and groundwater. Besides, the feasibility assessment of bioremediation in the investigated area is performed.M. Zargar, M. H. Sarrafzadeh, B. Taheri, and O. Tavakol

Computerized sales assistants: the application of computer technology to measure consumer interest - a conceptual framework

This paper describes a computerized intelligent sales assistant that gives sales personnel the ability to allocate their time where it will produce the best results, both for the customer, and for the business. Upon entering the shop, a potential customer has his features scanned and analyzed by the computer and the customer is categorized as a browser, future customer, potential customer or buyer. The customers‟ facial data are also used to retrieve their details, if available, from the shop‟s database, and the data are used to determine whether a human sales assistant is required. The intelligent assistant‟s expression recognition feature would also tell the sales personnel whether or not the customer requires or desires assistance in the first place. The paper also proposes a scenario whereby the system could be used to give online sales systems the ability to automatically tailor the services they offer to the customer based on their facial reactions. While browsing the contents of an e-shop, a customer has his facial expressions scanned and analyzed by the computer and, based on the results, the system can suggest further products that may be of interest to the customer. This, for the customer, can mean being directed to products they have been recognized to be more interested in, resulting in savings in time. The framework described in this paper could also be used for applications such as new product screening, marketing and advertising. This paper describes the theoretical and conceptual framework for such an intelligent sales assistant and discusses the technology used in its implementation

A scheduling algorithm for optimization and early planning in high-level synthesis

Complexities of applications implemented on embedded and programmable systems grow with the advances in capacities and capabilities of these systems. Mapping applications onto them manually is becoming a very tedious task. This draws attention to using high-level synthesis within design flows. Meanwhile, it is essential to provide a flexible formulation of optimization objectives as well as to perform efficient planning for various design objectives early on in the design flow. In this work, we address these issues in the context of data flow graph (DFG) scheduling, which is an essential element within the high-level synthesis flow. We present an algorithm that schedules a chain of operations with data dependencies among consecutive operations at a single step. This local problem is repeated to generate the schedule for the whole DFG. The local problem is formulated as a maximum weight noncrossing bipartite matching. We use a technique from the computational geometry domain to solve the matching problem. This technique provides a theoretical guarantee on the solution quality for scheduling a single chain of operations. Although still being local, this provides a relatively wider perspective on the global scheduling objectives. In our experiments we compared the latencies obtained using our algorithm with the optimal latencies given by the exact solution to the integer linear programming (ILP) formulation of the problem. In 9 out of 14 DFGs tested, our algorithm found the optimal solution, while generating latencies comparable to the optimal solution in the remaining five benchmarks. The formulation of the objective function in our algorithm provides flexibility to incorporate different optimization goals. We present examples of how to exploit the versatility of our algorithm with specific examples of objective functions and experimental results on the ability of our algorithm to capture these objectives efficiently in the final schedules

Handle transmitted vibration of electrical demolition hammers: Frequency and magnitude investigation in field measurements from different bits

Using a demolition hammer among the power tools is one of the most challenging job tasks for the operators of these tools, which exposes users to high levels of hand-transmitted vibrations. The focus of this study was for finding the vibration levels transmitted to the handles, the frequency content transmitted by the tool, and the effect of using insert bits with different tip shapes and lengths using conventional demolition hammers under controlled operating conditions on typical concrete slabs in the field. Three demolition hammers (weighing between 14 and 27 kg) with two handles installed were subjected to simultaneous measurements based on ISO 5349 as the field measurement technique. The findings demonstrated that even while the vertical axis dominated, several samples also produced equivalent x-axis results. The impact energy of the tools employed and the transmitted vibration to the tool handles are not significantly correlated with each other. All mean values were higher in the slabs with a thickness of 15 than those with 10 cm. The mean values of the total results for the two forms of flat and point tip inserted bits were 16.85 and 15.86 m/s(2), respectively, and in the samples with the same operating factors, this difference was more than 3 m/s(2) (p < .03). The a( wrms ) (frequency-weighted root mean square acceleration) produced at tools using 60 cm bits were more than those with a length of 40 cm, both for the average of the total results and the average of the results of each hammer. The difference between the average bit length groups over samples with the same factors reached 4.65 m/s(2) (p = .02). Frequency analysis for the flat and point insert bits with 60 cm length in the concrete slabs with a thickness of 15 cm showed that the dominant frequencies detected at lower frequencies for point bits. This difference is almost two frequency parts of 1/3 octave band