A MEMS-based pneumatic micro-conveyor for planar micromanipulation

This paper present a two dimensional pneumatic actuator based on silicon MEMS technology for objects micro-manipulation using tilted air jets. The device is composed of three layers stacked together, two micro-machined silicon wafers and a Pyrex glass wafer. The system is composed of a set of micro-conveyors in about 9 mm × 9 mm area. Each micro-conveyor has four nozzles and can generate tilted air-jets which allow four conveyance directions. An experiment of the conveyance of a silicon chip of 3 mm diameter and weighing approximately 2 mg was performed with pulsed air flow.     

Silicon nanowire arrays-induced graphene oxide reduction under UV irradiation

This paper reports on efficient UV irradiation-induced reduction of exfoliated graphene oxide. Direct illumination of an aqueous solution of graphene oxide at λ = 312 nm for 6 h resulted in the formation of graphene nanosheets dispersible in water. X-Ray photoelectron spectroscopy (XPS), UV-vis spectroscopy, atomic force microscopy (AFM) and electrochemical measurements (cyclic voltammetry and electrochemical impedance spectroscopy) suggest a restoration of the sp(2) carbon network. The results were compared with graphene nanosheets prepared by photochemical irradiation of a GO aqueous solution in the presence of hydrogenated silicon nanowire (SiNW) arrays or silicon nanowire arrays decorated with silver (SiNW/Ag NPs) or copper nanoparticles (SiNW/Cu NPs). Graphene nanosheets obtained by illumination of the GO aqueous solution at 312 nm for 6 h in the presence of SiNW/Cu NPs exhibited superior electrochemical charge transfer characteristics. This is mainly due to the higher amount of sp(2)-hybridized carbon in these graphene sheets found by XPS analysis. The high level of extended conjugated carbon network was also evident by the water insoluble nature of the resulting graphene nanosheets, which precipitated upon photochemical reduction.     

Development of energy-efficient passive solar building design in Nicosia Cyprus

Analyses have been done on different techniques of passive solar control using local climatic data (for 25-year period) to obtain physical building design. Our main aim is to provide general and appropriate information at strategic pre-design stages to make better use of passive solar energy in urban planning and building design for better indoor ‘comfort’ climate. It utilizes manual analysis techniques or Mahoney tables and ACHIPAK to develop ‘comfort zones’, and ‘control potential zones’, for the Capital City of Nicosia (Cyprus). The use of the control potential zones (CPZs) in pre-design of buildings and their objectives are discussed. Opportunities and limitations of the pre-design guidelines are also discussed.     

Recovering metal values hydrometallurgically from spent dry battery cells

A hydro-pyrometallurgical method was used to recover metal values from spent dry battery cells. Water-soluble ingredients were filtered, and solid residue was sorted by magnetic separation and water flotation. Parameters affecting the recovery efficiency were also studied. Results revealed that metallic parts, carbon rods, and paper were safely recovered; pure NH₄Cl, MnO₂, and ZnCl₂ salts were obtained. Maximum recovery efficiencies reached 93 percent for manganese and 99.5 percent for zinc and NH₄. For more information, contact M.A. Barakat, Central Metallurgical Research and Development Institute, Extractive Metallurgy Department, P.O. Box 87, Helwan, Cairo, Egypt; telephone 202-5010-647; fax 202-5010-639; e-mail rucmrdi@rusys.eg.net.     

Generalized infantile myofibromatosis in a patient with Turner's syndrome: a trial of interferon-alpha

A patient with Turner's syndrome was found to have generalized infantile myofibromatosis with visceral involvement at birth. The infant was treated with interferon-alpha because of the size of the lesions. Two months after treatment, the lesions appeared to have decreased in size and showed evidence of maturation with decreased apoptosis on histologic examination. Interferon-alpha treatment might induce regression of myofibromatosis.     

Integrated solar energy systems for rural electrification in Kenya

In sub-Saharan Africa where population is projected to increase by 124% in the next 20 years, grid extension has advanced more slowly than in any other major regions; only about a third of the urban residents, and a mere 8% of the rural population, are served by grid electricity. Today, it is estimated that nearly two billion people worldwide remain without access to electricity or the immediate prospect of grid electrification. The situation in Kenya is no different. About 80% urban and 99.5% rural households, respectively, in Kenya have no access to electricity and its services. The annual electricity demand currently stands at 6% and increasing. However, we have shown that Kenya is well endowed with abundant renewable energy (RE) potential, especially solar energy resources. In our study, we have observed that Kenya gets an annual average exposure to sunshine of about 10 h per day in most regions, and an annual mean radiation of 6.98 kW h/m², which if harnessed efficiently could contribute to improve quality of life in rural and poor urban sector in Kenya.     

Arteritis and fatal subarachnoid hemorrhage complicating occult Candida meningitis: unusual presentation in pediatric acquired immunodeficiency syndrome

We report the case of an 11-month-old child with acquired immunodeficiency syndrome, who despite treatment for systemic candidiasis developed undetected Candida meningitis. This uncommon manifestation of candidiasis was accompanied by basilar granulomatous inflammation and fibrosis of meninges with arteritis, vascular invasion by fungi, and terminal subarachold hemorrhage. To our knowledge, this constellation of findings has not been reported previously in pediatric acquired immunodeficiency syndrome.     

Decoupling without prediction of linear systems with delays: A structural approach

We exhibit, using a new structural approach specific for linear systems with delays, a necessary and sufficient condition for static row-by-row decoupling without prediction. Moreover, the decoupling problem is analyzed through two different concepts: the total one (without any time assumption), and the partial one (in a temporal mean), which can be considered if the total one has no solution.     

Digital embedded refractometer with temperature compensation

Temperature is one of the single most important factors influencing accurate refractometer readings and is one of the largest sources of error in measurement. A model based on neural networks, has been implemented to generate solution concentration data, knowing fluid temperature measurements in this solution. The neural network chosen in this study, is the hidden layer feed forward network. Its learning rule is based on the backpropagation of the error. Its training basis consists of concentration measurement, temperature data recorded every time. An in-line process measurement of refractive index (RI) works as a real-time predictive tool for the final concentration in process parameters is proposed. The acquired signal is transmitted, via the Bluetooth, to the processing and diagnostic unit. A predictive modelling using the neural networks enables us to predict its operation under various conditions within a temperature range from 0 up to 40 °C.     

Contrôle de topologie orienté stratégie basé sur des routeurs mobiles dédiés

Due to the inherent mobility within the ad hoc environment, network topology plays a key role on routing and network performance. In this paper we propose to control the ad hoc network morphology using a set of dedicated routers. The idea is to use positively the mobility, in order to enhance ad hoc network performance. Two deployment policies are studied for a global network connectivity or a limited network diameter. We describe the Mixed Integer Linear Programming (Milp) models for these deployment policies with respect to the constraints, and show the efficiency, of the described approach through simulations (NS-2).