Argyrophilic nucleolar organiser regions (AgNORs) in breast lesions

Nucleolar organiser regions (NORs) demonstrated by argyrophilia of NOR-proteins are indicator of cellular proliferative activity. The NORs can be identified in the nuclei as brown or black dots with silver colloidal staining technique in formalin fixed paraffin sections and in cytology smears. Seventy-five cases including 45 tissue sections and 30 fine needle aspiration cytology (FNAC) smears of benign and malignant lesions of breast have been studied to evaluate the significance and practical application of AgNOR count per nucleus. Out of 45 tissue sections 15 belonged to fibrocystic disease, 10 fibro-adenomas and 20 carcinomas and of the 30 FNAC smears, 10 were fibrocystic disease, 8 fibro-adenomas and 12 carcinomas. In fibrocystic disease the mean AgNOR count was 1.60 (FNAC group-0.75, tissue section-1.61). In fibro-adenomas it was 1.61 (FNAC-1.63, tissue section-1.59). The mean count in carcinoma was 12.10 (FNAC-12.08, tissue section-12.10). The difference in AgNOR count in fibrocystic disease and fibro-adenoma was not significant, but that between benign breast lesion and carcinoma was significant. No difference was observed between FNAC and tissue section groups in benign or malignant lesions. The simple staining technique can be used as an additional criterion to differentiate the benign and malignant lesions of breast.     

A note on assessing the superiority of a combination drug with a specific alternative

The gas atmosphere and medium composition are critical factors in the in vitro development of one- and two-cell embryos of several species. The present study evaluated the effect of different O2/CO2 concentrations (2/5, 2/10, 5/2.5, 5/5, 5/10, 10/10 and 21/5) on pig one- and two-cell embryo development. The embryos were individually cultured, for 6 days at 39 degrees C in a medium rich in bicarbonate and glutamine and containing pyruvate and lactate but lacking glucose. When the CO2 levels increased from 2.5% to 10%, the pH of the medium decreased from 8.2 to 7.5 and the development of the embryos was affected, but this depended mainly on the O2 levels. Pig embryo development was inhibited by 2 and 21% O2 levels. The optimum level for pig embryo development was 5% O2 and 5% CO2, whatever the criteria used to evaluate embryo development. At these optimal levels, the mean number of cells per embryo was 26 +/- 1.7 (ls mean +/- SE), and 50% of the one- and two-cell embryos developed to blastocysts. The substitution of 0.5% bovine serum albumin (BSA) in the medium by 0.3% polyvinyl-pyrrolidone (PVP) significantly decreased the one- and two-cell embryo development. When the calcium and chloride contents of the medium with PVP were reduced, however, the embryo development was similar to that observed in the medium containing BSA. Pig embryo development in vitro was found to be optimal under an atmosphere of 5% O2 and 5% CO2 and PVP could replace BSA as the high molecular weight supplement.     

Integral equation solution for analyzing scattering fromone-dimensional periodic coated strips

A set of integral equations based on the surface/surface formulation are developed for analyzing electromagnetic scattering by one-dimensional periodic structures. To compare the accuracy, efficiency, and robustness of the formulation, the electric field integral equation (EFIE), magnetic field integral equation (MFIE), and combined field integral equation (CFIE) are developed for analyzing the same structure for different excitations. Due to the periodicity of the structure, the integral equations are formulated in the spectral domain using the Fourier transform of the integrodifferential operators. The generalized-biconjugate-gradient-fast Fourier transform method with subdomain basis functions is used to solve the matrix equation     

Effect of second phase precipitates on recovery and recrystallization behaviour of cold-worked Al2024-SiCp composites

The restoration behaviour of SiC particle reinforced 2024-aluminium composite has been studied under conditions where recrystallization-grain growth and precipitation occur concurrently. An emphasis has been given to understanding the recrystallization-precipitation interaction, in the presence of SiC_p, during annealing. The composite was fabricated by a casting route followed by hot extrusion. Samples were cold deformed to a reduction in height of either 30 or 42 per cent following a heat treatment. The kinetics of recrystallization has been studied in the temperature range 100–485°C. Recrystallization has been monitored by optical microscopy, coupled with hardness measurements. It has been observed that the composite has a lower recrystallization temperature compared to that of an unreinforced alloy under identical annealing conditions. Following recrystallization, grain growth has been noticed in the composite. Although the degree of cold deformation showed some effect on the recrystallization temperature of the composite, it was found to be a weak controlling factor for average recrystallized grain size. Results showed that, in spite of the hardness reduction due to recrystallization-grain growth, the hardness of a composite can be partially restored by concurrent solid solution hardening (dissolution of precipitates) and also by the generation of dislocations during quenching to a low temperature.     

Noise response of tri-state phase frequency detector

An analytical expression describing the characteristics of a tri-state phase frequency detector is presented. Using this relation, uniform phase jitter and additive noise responses of the said system are analytically studied and the results are compared with simulated responses     

Comparative thermal performance evaluation of an active solar distillation system

In this paper, thermal models of all types of solar collector‐integrated active solar stills are developed based on basic energy balance equations in terms of inner and outer glass temperatures. In this paper, hourly yield, hourly exergy efficiency, and hourly overall thermal efficiency of active solar stills are evaluated for 0.05 m water depth. All numerical computations had been performed for a typical day in the month of 07 December 2005 for the climatic conditions of New Delhi (28°35′N, 77°12′E, 216 m above MSL). The thermal model of flat‐plate collector integrated with active solar still was validated using the experimental test set‐up results. Total daily yield from active solar still integrated with evacuated tube collector with heat pipe is 4.24 kg m^?2 day^?1, maximum among all other types of active solar stills. Copyright © 2007 John Wiley & Sons, Ltd.     

Learning while solving problems in best first search

We investigate the role of learning in search-based systems for solving optimization problems. We use a learning model, where the values of a set of features can be used to induce a clustering of the problem state space. The feasible set of h* values corresponding to each cluster is called h*set. If we relax the optimality guarantee, and tolerate a risk factor, the distribution of h*set can be used to expedite search and produce results within a given risk of suboptimality. The off-line learning method consists of solving a batch of problems by using A* to learn the distribution of the h*set in the learning phase. This distribution can be used to solve the rest of the problems effectively. We show how the knowledge acquisition phase can be integrated with the problem solving phase. We present a continuous online learning scheme that uses an “anytime” algorithm to learn continuously while solving problems     

Energetic and Exergetic Performances of Plate Heat Exchanger Using Brine-Based Hybrid Nanofluid for Milk Chilling Application

Abstract

Theoretical study on the energetic and exergetic performances of a counter-flow corrugated plate heat exchanger using hybrid nanofluids for the milk chilling application has been done in the present investigation. Magnesia-silver and Alumina-silver nanoparticles have been dispersed in the ethylene glycol–water mixture and propylene glycol–water mixture (20:80 brine solutions) with different particle volume concentration separately. Effect of particle volume concentration and flow rate of the hybrid nanofluid on the heat transfer rate, convective, and overall heat transfer coefficients, mass flow rate of milk, pressure drop, pumping power, entropy generation rate, second law efficiency, irreversibility, irreversibility distribution ratio, non-dimensional exergy (NDE) destruction, and performance index have been studied. It has been observed that heat transfer rate, convective and overall heat transfer coefficients, pressure drop, pumping power, irreversibility, entropy generation rate, second law efficiency, and milk flow rate increase; while NDE destruction, performance index, and irreversibility distribution ratio decrease with the hybrid nanofluid flow rate and the volume concentration of the nanofluid. Within studied ranges, the hybrid nanofluid yields the maximum improvement of heat transfer rate and convective heat transfer coefficient of about 1.6% and 9.4%, respectively, compared to base fluid. It has also been found that silver?+?alumina shows slightly better performance improvement and hence hybrid nanofluid is recommended as a suitable alternative for the milk chilling units.