A subthreshold low-power CMOS LC-VCO with high immunity to PVT variations

This paper presents a current driver with a novel high voltage (HV) switch schematic for the use as a protective switch for recording circuits during the stimulation sequence in neural measurement system. The current driver can source and sink currents of amplitudes up to ±8.2 mA with a HV tolerance from 30 V up to 120 V. The proposed HV switch also tolerates the voltage difference up to 120 V between its terminals. Between stimulation sequences the driver provides the effective isolation of the stimulation electrode from ground and HV supply voltage. The inter pulse current is no more than 60 pA. The chip was fabricated with AMS HV 0.35 \(\mu\)m CMOS technology. For test purposes the complete stimulation system including the proposed chip and the external C8051F410 controller was build. For the proposed system the mismatch between the sourced and sinked current does not exceed 20 \(\mu\)A. The possibility to stimulate with frequencies up to 1 kHz is proven by measurement along with the electrode-tissue model.     

Experimental Visualization and Investigation of Multiphase Flow Regime Transitions in Two-Dimensional Trickle Bed Reactors

Different flow regimes are known to occur in the interaction of multiphase gas–liquid flows over packed beds of solid particles, such as those observed in trickle bed reactors (TBRs). There are four major flow regimes that are known to occur in downward cocurrent flow in TBRs, namely: trickle, pulse, bubble, and mist flow regimes. In this work, the focus is on macro-scale experimental visualizations and investigations of the flow regimes in a two-dimensional TBR.

Experimental observations are made to investigate the development and transition of these flow regimes over a wide range of liquid and gas velocities. Cylindrical particles are placed between two glass plates that are sealed on the sides, and water and air are injected over them using an injection manifold to simulate multiphase flow in a TBR. A diffused light emitting device (LED) light table is used to illuminate the experimental window, while real time images are obtained using a high-speed camera. Flow maps are reported depicting all four regimes and the transition regions between them. Transition regions occur where the characteristics of more than one flow regime coexist.

The 2D experimental results are then compared with the existing literature data of three dimensional results and found to be in good agreement. Emphasis is placed on the transition between the trickle and pulse regimes, since that is the most important mode of operation in industrial TBRs. It is observed that the change in diameters of the cylindrical particles in a two-dimensional TBR has little effect on the transition between the flow regimes when the porosity of the bed is kept constant.     

Synthetic Co-Attractants of the Aggregation Pheromone of the Date Palm Root Borer <Emphasis Type="Italic">Oryctes agamemnon</Emphasis>

Laboratory and field investigations to identify and evaluate plant co-attractants of the aggregation pheromone of the date palm pest Oryctes agamemnon are reported. Volatiles emitted by freshly cut palm core and palm core with feeding males, were collected, analyzed by gas chromatography coupled to mass spectrometry and evaluated in olfactometers alone or combined with synthetic pheromone. A collection of palm odor without male effluvia was attractive alone and enhanced attraction to synthetic pheromone in an olfactometer similar to that to a collection of palm odor emitted with feeding males and containing natural pheromone. Behavioral responses to collections of palm volatiles were correlated to the amount of volatiles material in them. Enhancement of the attractiveness of the pheromone was not correlated to chemicals specific to beetle feeding. The chemicals common to the active collections extracts were benzoate esters, mostly ethyl benzoate, anisole derivatives and sesquiterpenes. Blends of the most abundant components of the extracts were evaluated for enhancement of the attractiveness of pheromone (1 μg) in olfactometers at 1 or 10 μg doses. The mixtures were further evaluated by field trapping in Tunisia at 3–10 mg/day using reference (6 mg/day) or experimental pheromone formulations. A mixture of ethyl benzoate, 4-methylanisole and farnesol (1:1:1 w/w at 6.5 mg/day) enhanced captures in pheromone baited traps in 2014 and 2015 and this mixture was as active as the natural palm bait. The practical prospect of the result for the management for O. agamemnon, and other palm beetles is discussed.     

Synthesis,Crystal Structure,Electrochemical and Catalytic Properties of Hybrid Polyoxomolybdate Clusters-Based Terbium Complex

The inorganic–organic compound based on polyoxomolybdate [Tb(C₂H₆SO)₈][PMo₁₂ O₄₀]·2C₂H₆SO·½H₂O (I) has been isolated and structurally characterized by single-crystal X-ray molecular structure, IR spectra, thermogravimetric analysis and cyclic voltammetry measurements. The catalytic activities of (I) were also tested. The title compound crystallizes in monoclinic crystal system with C2/c space group. In the crystal, the polyoxidometalate anions are arranged in chains parallel to the [010] direction. The complex cations are located between these layers and linked to the neighbouring anions via weak C–H?O hydrogen bonding interactions leading to the formation of three dimensional network structure. Their catalytic activity toward organic dye is quite sizeable since the target removal is about 68% in the presence of the system POM-Tb/H₂O₂ after 120 min.     

Influence of sulfur fertilization on S-containing, phenolic, and carbohydrate metabolites in rosy garlic (Allium roseum L.): a wild edible species in North Africa

Allium roseum L., a North African endemic species, is a rich source of many important nutrients and bioactive compounds responsible for many promising beneficial health physiological effects. The influence of sulfur fertilization (S fertilization) on the flavor, total polyphenols, and carbohydrates content in A. roseum was studied, using three sulfur concentrations (0.01, 1.50 and 4.50 mmol L^?1) under controlled conditions. S fertilization showed a significant increase in the allicin concentration of A. roseum bulbs with an average of 0.859–2.285 g kg^?1 FW for bulbs grown at 0.01 and 1.50 mmol L^?1 SO₄ ^2?, respectively. The same trend was observed for total polyphenol content. On the contrary, the highest level of S decreased the content of reduced carbohydrates. These results provide evidence that the concentrations of allicin and polyphenols in A. roseum are increased by S fertilization, potentially amplifying its beneficial impacts on health.     

Virgin olive oil (VOO) production in Tunisia: The commercial potential of the major olive varieties from the arid Tataouine zone

The commercial potential of olive oils from three consecutive crop years, derived from the main autochthonous olive varieties Chemlali Tataouine, Fakhari Douirat, Zarrazi Douirat and Dhokar Douirat grown in the arid region of Tataounine (Tunisia) was examined with regards to stability and nutrition aspects. Several characteristics such as fatty acid composition, the extremely high phenol-type antioxidant content, and the low levels of green pigments suggested that these oils, the only fat source for the local people, are of promising composition. Efforts to develop commercial products from these varieties could improve antioxidant intake of the local population. The introduction of Good Manufacturing Practices is a prerequisite so that the quality observed for oils obtained by an Abencor system to be achieved also in real life. This can be feasible through appropriate oleoculture, which is often the only viable agricultural activity in remote arid regions such as Tataouine.     

An Optimized SW/HW AVMF Design Based on High-Level Synthesis Flow for Color Images

In this paper, a software/hardware High-level Synthesis (HLS) design is proposed to compute the Adaptive Vector Median Filter (AVMF) in real-time. In fact, this filter is known by its excellent impulsive noise suppression and chromaticity conservation. The software (SW) study of this filter demonstrates that its implementation is too complex. The purpose of this work is to study the impact of using an HLS tool to design ideal floating-point and optimized fixed-point hardware (HW) architectures for the AVMF filter using square root function (ideal HW) and ROM memory (optimized HW), respectively, to select the best HLS architectures and to design an efficient HLS software/hardware (SW/HW) embedded AVMF design to achieve a trade-off between the processing time, power consumption and hardware cost. For that purpose, some approximations using ROM memory were proposed to perform the square root and develop a fixed-point AVMF algorithm. After that, the best solution generated for each HLS design was integrated in the SW/HW environment and evaluated under ZC702 FPGA platform. The experimental results showed a reduction of about 65% and 98% in both the power consumption and processing time for the ideal SW/HW implementation relative to the ideal SW implementation for an AVMF filter with the same image quality, respectively. Moreover, the power consumption and processing time of the optimized SW/HW are 70% and 97% less than the optimized SW implementation, respectively. In addition, the Look Up Table (LUTs) percentage, power consumption and processing time used by the optimized SW/HW design are improved by nearly 45%, 18% and 61% compared the ideal SW/HW design, respectively, with slight decrease in the image quality.