Statistical Design of Low Power Square-Law CMOS Cells for High Yield

A robust design of low voltage low power square law CMOS composite cells using statistical VLSI design techniques is presented. Since random device/process variations do not scale down with feature size or supply voltage, the statistical design of low voltage circuits is essential in order to keep functional yields of low voltage circuits at levels that are competitive and cost effective. The Response Surface Methodology and Design of Experiment techniques were used as statistical techniques. This article shows that statistical techniques will result in area/layout optimization which will enhance functional yield of low voltage analog ICs.     

Biological activities of the essential oil and methanolic extract of Micromeria fruticosa (L) Druce ssp serpyllifolia (Bieb) PH Davis plants from the eastern Anatolia region of Turkey

The in vitro antimicrobial and antioxidant activities of the essential oil and methanolic extract of Micromeria fruticosa ssp serpyllifolia as well as the composition of the essential oil were examined. The essential oil exhibited activity against 14 bacteria, three fungi and a yeast, with minimal inhibitory concentration (MIC) values ranging from 31.25 to 125 µl ml^?1, whilst the methanolic extract was inactive. Antioxidant activity was measured by two methods, namely scavenging of the free radical DPPH and inhibition of linoleic acid oxidation. The methanolic extract exhibited significant antioxidant activity in both assays, providing 50% inhibition at 70.9 ± 0.5 µg ml^?1 concentration in the DPPH assay and inhibiting linoleic acid oxidation to 59% at 2 mg ml^?1 concentration, whilst the essential oil showed activity only at higher concentrations. The gallic acid equivalent total phenolic content of the methanolic extract was found to be 55.2 ± 2.00 µg mg^?1 dry weight extract (5.5% w/w). The chemical composition of the hydrodistilled essential oil was analysed by means of GC/MS. Twenty‐nine constituents were identified, the main ones being piperitenone (50.61%) and pulegone (29.19%). Copyright © 2004 Society of Chemical Industry     

Model Predictive Control Coupled with Artificial Intelligence for Eddy Current Dynamometers

The recent studies on Artificial Intelligence (AI) accompanied by enhanced computing capabilities supports increasing attention into traditional control methods coupled with AI learning methods in an attempt to bringing adaptiveness and fast responding features. The Model Predictive Control (MPC) technique is a widely used, safe and reliable control method based on constraints. On the other hand, the Eddy Current dynamometers are highly nonlinear braking systems whose performance parameters are related to many processes related variables. This study is based on an adaptive model predictive control that utilizes selected AI methods. The presented approach presents an updated the mathematical model of an Eddy Current Dynamometer based on experimentally obtained system operational data. Finally, the comparison of AI methods and related learning performances based on the assessment technique of mean absolute percentage error (MAPE) issues are discussed. The results indicate that Single Hidden Layer Neural Network (SHLNN), General Regression Neural Network (GRNN), Radial Basis Network (RBNN), Neuro Fuzzy Network (ANFIS) coupled MPC have quite satisfying performances. The presented results indicate that, amongst them, GRNN appears to provide the best performance.     

New current–mode special function continuous-time active filters employing only OTAs and OPAMPs

This paper reports three current mode second order filters, each of which realizes a specific function without any external passive elements. These filters realize low-pass notch (LPN), high-pass notch (HPN) and all-pass (AP) functions. Two OPAMPs, a double output OTA and a single output OTA are employed for each circuit. The filter structures can be easily cascaded since they have high output impedances. This property is especially useful for achieving high-order filters using these LPN and HPN filters as building blocks. The presented theory is verified with macro models in SPICE simulations and, using the SPICE parameters of the layout technology, post layout simulations are carried out, with parasitics extracted from the layouts of the filter chips.     

Realization of Current-Mode Third Order Butterworth Filters Employing Equal Valued Passive Elements and Unity Gain Buffers

This paper describes current-mode third-order Butterworth filter topologies realized with unity gain active elements and minimum number of passive components. All capacitors and resistors are equal valued. The core of the circuit realizes HP, BP and LP functions easily. The filter exhibits high output impedance. Experimental results are included to verify theory.     

Effects of surface-finishing forms and cement-filling on porous dimension limestone deterioration in cold regions

This work studies the influences of both surface-finishing forms and cement-filling on the durability of dimension limestone in cold regions. Freeze-thaw cycles, aqueous saline solution and their interactions with surface-finishing forms and cement-filling on stones were investigated for two types of porous limestone, Caribbean and Pewter Blend. Both deionised water and saline water composed of 20% NaCl by weight were used, and 28 freeze-thaw cycles were applied to the samples. The change in dry weight, porosity, and Böhme abrasion loss value was obtained for all test samples. It was observed that two types of porous limestone with cement-filling and different types of surface-finishing were influenced to different extents by freeze-thaw and salt. Experiments showed that stones to be used outdoors in cold regions should have relatively low initial porosity and that they should be fine-finished and cement-filled; these modifications to the stones will maximise the benefit received from the stones.     

Clozapine Increases Nestin Concentration in the Adult Male Rat Hippocampus: A Preliminary Study

Patients with schizophrenia, and rodent models of the disease, both exhibit suppressed neurogenesis, with antipsychotics possibly enhancing neurogenesis in pre-clinical models. Nestin, a cytoskeletal protein, is implicated in neuronal differentiation and adult neurogenesis. We hypothesized that schizophrenia pathogenesis involves nestin downregulation; however, few studies have related nestin to schizophrenia. We assessed nestin protein concentration, prepulse inhibition (PPI), and social interaction in the MK-801 model of schizophrenia, with or without antipsychotic (clozapine) treatment. Adult male Sprague–Dawley rats were intraperitoneally administered saline or MK-801 (0.1 mg/kg) to produce a schizophrenia-like phenotype, with concomitant subcutaneous injections of vehicle or clozapine (5 mg/kg). PPI was assessed on days 1, 8, and 15, and social interaction was assessed on day 4. Hippocampus tissue samples were dissected for Western blotting of nestin concentration. MK-801 alone did not alter nestin concentration, while clozapine alone enhanced hippocampal nestin concentration; this effect was not apparent in animals with MK-801 and clozapine co-administration. MK-801 also produced schizophrenia-like PPI disruptions, some of which were reversed by clozapine. Social interaction deficits were not detected in this model. This is the first report of clozapine-induced enhancements of hippocampal nestin concentration that might be mediated by NMDA receptors. Future studies will explore the impact of neurodevelopmental nestin concentration on symptom onset and antipsychotic treatment.