Scopolamine injection into the olfactory bulb impairs short-term olfactory memory in rats.

A previous experiment showed that systemic administration of the muscarinic antagonist scopolamine altered delayed matching in an olfactory task in rats. The present experiment tested whether the impairment could result from blockade of the cholinergic transmission in the first relay structure of the olfactory system, the olfactory bulb. 25 rats served as Ss. The drug was infused directly into both olfactory bulbs before test sessions. Results show that the intrabulbar infusion reproduced the effect of the systemic administration. With a 4-sec delay between target odor and choice test, performances of treated rats remained unchanged; however, with a 30-sec delay, rats performed randomly. Results from a complementary electrophysiological experiment in anesthetized rats support the idea that scopolamine injected into the olfactory bulb was unlikely to have reached more central structures. Further evidence for the involvement of pure sensory areas in short-term memory is concluded. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An improved adaptive dual prediction scheme for reducing data transmission in wireless sensor networks

Wireless Networks - Currently one of the main problem for wireless networks is the medium access control. Hence, the number of data transmissions in wireless sensor networks should be optimized to...     

Extended equivalent linear model (X-ELM) to assess liquefaction triggering: Application to the City of Urayasu during the 2011 Tohoku earthquake

This paper proposes a hybrid iterative approach to evaluating the liquefaction potential and settlements when liquefaction is not triggered for a saturated sand deposit subjected to seismic motion. The proposed method is a combination of an equivalent linear dynamic analysis and an empirical pore pressure build-up model. The two concepts are combined to account for the increase of pore-water pressure in the dynamic response. This extended equivalent linear model, or X-ELM, introduces a parameter $\chi$ identified by means of an extensive set of computations and observations. The approach has been validated in the case of Urayasu City during the 2011 Great East Japan Earthquake. The X-ELM enables the assessment of the triggering of the soil liquefaction of 12 representative soil profiles, namely, four profiles representing non-liquefied grounds in the old town of Urayasu and eight profiles representing the liquefaction-prone grounds in the reclaimed area of the city. The X-ELM computed areas of triggered liquefaction or non-liquefaction are found to be in good agreement with qualitative observations and in-situ measured responses.     

Photocatalytic degradation of two volatile fatty acids in an annular plug-flow reactor; kinetic modeling and contribution of mass transfer rate

This study investigates the influence of inlet concentration and of flow rate on the degradation rate of two Volatile Fatty Acids (butyric and propionic acids). TiO2-coated nonwoven fiber textile was used as the photocatalyst in an annular plug-flow reactor at laminar flow regime. The kinetic follows a Langmuir-Hinshelwood form. The oxidation rate increased with the flow rate, which emphasizes the influence of the mass transfer. A first design equation is proposed considering that the mass transfer could be neglected. Despite a good accuracy of the model, the determined kinetic constants are dependent on the flow rate which highlights the contribution of the mass transfer rate on the global degradation rate. Thus, a new design equation which includes the mass transfer rate was developed. Using this model, the degradation rate can be determined for any given flow rate. Moreover, it allows the estimation of the contribution of mass transfer and chemical reaction steps at given experimental conditions; and thus providing an interesting tool for reactor optimization or design.     

Algerian Silica Behavior Study at High Temperature for Carbothermic Process

Silicon - Silica is used as raw material for metallurgical grade silicon production intended for photovoltaic field. Our work consists to study the silica behavior (sandstones, quartz) from two...     

Wireless sensor networks for rehabilitation applications: Challenges and opportunities

Rehabilitation supervision has emerged as a new application of wireless sensor networks (WSN), with unique communication, signal processing and hardware design requirements. It is a broad and complex interdisciplinary research area on which more than one hundred papers have been published by several research communities (electronics, bio-mechanical, control and computer science). In this paper, we present WSN for rehabilitation supervision with a focus on key scientific and technical challenges that have been solved as well as interdisciplinary challenges that are still open. We thoroughly review existing projects conducted by several research communities involved in this exciting field. Furthermore, we discuss the open research issues and give directions for future research works. Our aim is to gather information that encourage engineers, clinicians and computer scientists to work together in this field to tackle the arising challenges. We believe that bridging researchers with different scientific backgrounds could have a significant impact on the development of WSN for rehabilitation and could improve the way rehabilitation is provided today.     

Optimal state filter from sequential unknown input reconstruction: Application to distributed state filtering

This paper generalizes Kalman filtering with an intermittent unknown input problem to be left invertible discrete‐time stochastic linear systems with zero, one, or more structural delays. Contrary to the state filtering–based system inversion where the unknown input vector is reconstructed with a time delay that is equal to the structural delay of the plant, we propose an optimal state filtering by reconstructing some linear combinations of the unknown input vector with a time delay less than the structural delay. Designed under a sequential unknown input decoupling constraint, which has never been previously studied in the literature, all presented filters are very computationally efficient. The proposed state filtering is used to solve the autonomous distributed state filtering problem in large‐scale networked control systems when the unknown input vector represents interactions between subsystems and when each subsystem receives intermittent information about the interaction from unreliable networks. The stochastic stability conditions of the extended intermittent unknown input Kalman filter are established when the arrival binary sequence of packet dropouts follows a random Bernoulli process.     

Finite element analysis of linear plates buckling under in-plane patch loading

The elastic buckling load is physically important in design because it is actually the critical step in the changing plate configuration that will eventually lead to complete failure. The present work investigates the problem of linear buckling of simply supported thin plates subjected to patch compression. In order to satisfy the boundary conditions in a rigorous way, the authors chose the finite element method using the exact stress distribution throughout the plate.In the present paper, the stability problem treated using the total energy is briefly outlined. The plate modelling is made by means of an eight noded rectangular element and a reduction of variable strategy is applied to estimate the number of degrees of freedom leading to little or no loss in seeking solution accuracy.The buckling coefficient is determined for different load cases applied to a range of plate with various edge ratios. The achieved results are summarised through different graphs representing variation of the buckling coefficient against the plate ratio for each load case treated. A comparison with previous works is made. Finally, it is shown that the resolution of the plate buckling problem using true stress distribution with the finite element method leads to a good agreement with results previously obtained by means of analytical methods using an exact stress distribution.     

Assessment of green roof thermal behavior: A coupled heat and mass transfer model

Green roofs have a positive effect on the energy performance of buildings, providing a cooling effect in summer, along with a more efficient harnessing of the solar radiation due to the reflective properties found inside the foliage. For assessing these effects, the thermodynamic model was developed as well as the thermo-physical properties of the green roof components were characterized. Its typologies and vegetation styles should also be studied. The proposed model is based on energy balance equations expressed for foliage and soil media. In this study, the influence of the mass transfer in the thermal properties and evapotranspiration were taken into account. We then added the water balance equation into our model and performed a numerical simulation. By assuming the outdoor conditions, the roof support temperature and the drainage water as inputs, the model evaluates the temperatures evolution at foliage and soil ground levels. A parametric study was performed using the proposed model to classify green roofs depending on the considered climate condition. Comparisons were undertaken with a roof slab concrete model; a significant difference (of up to 30 °C) in temperature between the outer surfaces of the two roofs was noticed in summer. The model was experimentally validated according to green roof platform, which was elaborated. The mass transfer effect in the subtract was very effective in reducing the model errors. Simulation results show that the use of vegetation in the roof building improves not only thermal comfort conditions, but the energy performance of a building.