Effect of Sieve Size for wet and Dry Screening on the Physical Properties of Lactose Granules and Their Corresponding Tablets

Various batches of lactose granules were prepared by wet granulation process using acacia, cassava starch and polyvinylpyrrolidone separately as binders by inter-changing sieves for wet and dry screening, The effects of wet and dry screen aperture sizes together with the effects of the binders used on the physical properties of such granules and the corresponding tablets were investigated. The bulk volume of granules was found to be increased as the aperture size of sieves for dry screening increased while keeping a particular sieve constant for wet screening. No significant difference was observed with regards to the effect of sieve size upon the flow rate.

It was also observed that keeping the sieve size for wet screening constant, the mean tablet weight increased while the tablet weight variation decreased as the sieve size for dry screening decreased. There found to be an observable relationship between the sieve sizes used for dry and wet screening, average granule size and hardness of tablets. When a particular sieve was kept constant for wet screening, an increase in the sieve aperture size for dry screening resulted in an increase in average granule size and a decrease in tablet hardness. This may be due to increase in void space, decrease in die fill and less bonding between the granules. The disintegration time of the tablets was found to be significantly influenced by the sieve size combination used for wet and dry screening. When sieves for wet screening were kept constant, an increase in the sieve size for dry screening generally produced tablets of lower disintegration time.     

Low frequency of Ras gene mutation in spontaneous and gamma-ray-induced thymic lymphomas of scid mice

BACKGROUND: Workers in the poultry industry have increased frequencies of respiratory health problems. The aim of the present study was to investigate acute health effects from exposure in poultry houses and to compare the health effects observed in a cage rearing system and the alternative "cage-less" rearing system for laying hens. METHODS: Thirty-four subjects were exposed for 3 hr in confined poultry houses. The subjects were randomized into three groups: one was exposed in a building with a cage rearing system and the two other groups were exposed in buildings with a cage-less system, with either young hens and fresh bedding material or with older hens and old bedding material. RESULTS: Inhalable dust levels were approximately 4 mg/m3 in the buildings with the cage-less system and 2 mg/m3 in the building with cage rearing system; the endotoxin concentration was approximately 100 ng/m3 in both systems. Bronchial responsiveness to methacholine increased approximately fivefold in all groups following exposure. The concentration of the proinflammatory cytokine interleukin-6 (IL-6) increased in nasal lavage fluid and in peripheral blood as a result of the exposure. The number of leukocytes in peripheral blood increased only in the groups exposed among loose laying hens. CONCLUSION: In the present study, we have demonstrated among previously non-exposed subjects, that 3-hr exposure in confined buildings for egg production induces an acute inflammatory reaction in the upper airways and increased bronchial responsiveness. There is a tendency towards stronger reactions in the groups exposed in the buildings with loose housing for laying hens.     

On zeros and responses of linear regulators and linear observers

In the pole assignment of the single input and output regulator, there is a case where the integrated square output becomes infinite and the response of the output has an infinitely large maximal amplitude when all poles of the closed loop system are assigned to negative infinity in the numericals-plane. This paper deeply investigates this problem from the linear structure point of view and applies the obtained results to the pole specification problem of observers.     

β-galactosidase immobilization on premodified Teflon membranes using γ-radiation grafting

γ-Radiations have been used to immobilize, by mutual grafting, the β-galactosidase enzyme and monomers of 2-hydroxyethyl methacrylate on Teflon (polytetrafluoroethylene) membrane previously grafted with acrylic acid monomers. This double grafting technique improved the catalytic activity of the membrane. Membrane activity has been studied as a function of some of the most relevant parameters affecting the grafting degree and of the amount of enzyme used for immobilization. Experimental conditions producing the best membrane activity have been characterized. The advantages in using Teflon catalytic membrane in nonisothermal bioreactors, more efficient than the analogous isothermal bioreactors, are also discussed. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 625–636, 1998     

Complete solution of the 4‐block H∞ control problem with infinite and finite jω‐axis zeros

This paper discusses the 4‐block H^∞ control problem with infinite and finite jω‐axis invariant zeros in the state‐space realizations of the transfer functions from the control input to the controlled output and from the disturbance input to the measurement output, where these realizations are induced from a stabilizable and detectable realization of the generalized plant. This paper extends the DGKF approach to the H^∞ control problem but permitting infinite and finite jω‐axis invariant zeros by using the eigenstructures related to these zeros. Necessary and sufficient conditions are presented for checking solvability through checking the stabilizing solutions of two reduced‐order Riccati equations and examining matrix norm conditions related to the jω‐axis zeros. The parameterization of all suitable controllers is given in terms of a linear fractional transformation involving a certain fixed transfer function matrix and together with a stable transfer function matrix with gain less than 1 which is free apart from satisfying certain interpolation conditions. Copyright © 2000 John Wiley & Sons, Ltd.     

Performance of Multipath Routing for On-Demand Protocols in Mobile Ad Hoc Networks

Mobile ad hoc networks are characterized by multi-hop wireless links, absence of any cellular infrastructure, and frequent host mobility. Design of efficient routing protocols in such networks is a challenging issue. A class of routing protocols called on-demand protocols has recently found attention because of their low routing overhead. The on-demand protocols depend on query floods to discover routes whenever a new route is needed. Such floods take up a substantial portion of network bandwidth. We focus on a particular on-demand protocol, called Dynamic Source Routing, and show how intelligent use of multipath techniques can reduce the frequency of query floods. We develop an analytic modeling framework to determine the relative frequency of query floods for various techniques. Our modeling effort shows that while multipath routing is significantly better than single path routing, the performance advantage is small beyond a few paths and for long path lengths. It also shows that providing all intermediate nodes in the primary (shortest) route with alternative paths has a significantly better performance than providing only the source with alternate paths. We perform some simulation experiments which validate these findings.     

A fast driver circuit for single-photon sensors

A fast active quenching and recharging circuit (AQRC) for single-photon avalanche diodes (SPAD) is presented in this paper. The proposed driver exhibits a lower than 10 ns overall quenching time allowing a tunable excess voltage from 5 to 12 V. The circuit was designed by using the dielectrically insulated BiCMOS technology supplied by ST Microelectronics. Many post-layout ELDO simulations have validated the high performance of the proposed topology, which is actually the fastest AQRC reported in the literature.     

Real-time road surface and semantic lane estimation using deep features

In this article, we present a robust real-time road surface and semantic lane marker estimation algorithm using the deconvolution neural network and extra trees-based decision forest. Our proposed algorithm simultaneously performs three environment perception tasks on colour and depth images, even under challenging conditions, namely road surface estimation, lane marker localization, and lane marker semantic information estimation. The lane marker semantic information implies the lane marker type such as dotted lane marker or continuous lane marker. The task of road surface estimation is performed with a trained deconvolution neural network. For the lane marker localization task, a scene-based extra trees regression framework is used to localize the lane markers in the given road. To account for the variations in the number and characteristics of the lane markers in the road scene, multiple regression models indexed with scene labels are used. The pre-defined scene labels correspond to the lane marker variations in a given scene, and an extra trees-based classification model is trained to estimate them from the road features. The road features, given as an input to the extra trees frameworks, are extracted from the road image using the trained filters of the deconvolution network. The proposed algorithm is validated using multiple acquired datasets. A comparative analysis is also conducted with baseline algorithms, and an improved accuracy is reported. Moreover, a detailed parameter evaluation is also performed. We report a computational time of 90 ms per frame.     

Systolic array architecture implementing Berlekamp-Massey-Sakata algorithm for decoding codes on a class of algebraic curves

We construct a two-dimensional systolic array implementing the Berlekamp-Massey-Sakata (BMS) algorithm to provide error-locator polynomials for codes on selected algebraic curves. This array is constructed by introducing some new polynomials in order to increase the parallelism of the algorithm. The introduced polynomials are used in the majority logic scheme by Sakata et al. to correct errors up to the designed minimum distance without affecting its high speed. The arrangement of the nearest local connection of processing units in the systolic array is obtained for the general case. Furthermore, shortened systolic arrays that reduce the circuit scale and have the same function are constructed with only a slight modification of the connections and controls; this enables the adjustment of the circuit scale for different types of systems.     

High reversible capacities of graphite and SiO/graphite with solvent-free solid polymer electrolyte for lithium-ion batteries

The combination of graphite or silicon monoxide (SiO)/graphite = 1/1 mixture with a solvent-free solid polymer electrolyte (SPE) was fabricated using a new preparation process, involving precoating the electrode with vapor-grown carbon fiber (VGCF) and binders (polyvinyl difluoride: PVdF or polyimide: PI), followed by the overcoating of the SPE. The reversible capacity of [graphite | SPE | Li] and [SiO/graphite | SPE | Li] cells were >360 and >1000 mAh g⁻¹ with 78% and 77% for the 1st Coulombic efficiency, respectively. The reversible capacities were 75% at the 250th cycle for [graphite | SPE | Li] and 72% at the 100th cycle for [SiO/graphite | SPE | Li]. The electrode used was compatible with that of the conventional liquid electrolyte system, and the SPE film could be formed on the electrode by the continuous overcoating process, which will lead to a low-cost electrodes and low-cost battery production. The solid-state lithium-ion polymer battery (SSLiPB) developed in this study, which consisted of [LiFePO₄ | SPE | graphite], showed the reversible capacity of 128 mAh g⁻¹ (based on the LiFePO₄ capacity) with favorable cycle performance.