Optimum tilt angles of a solar collector

Optimum tilt angles for solar collectors at 171 locations in North America were determined. As a matter of user convenience, equations predicting optimum collector tilt angle were derived by using regression analysis based on the results obtained for the 171 locations for several different periods of the year. These equations adequately predict the optimum tilt angles as indicated by the R² values of 0.814 to 0.920.     

Bone SPECT imaging of vertebral hemangioma correlation with MR imaging and symptoms

To evaluate the bone SPECT findings of vertebral hemangioma and their relationship to symptoms and MRI findings, the authors reviewed planar and SPECT bone scans and MR images of 15 vertebral hemangioma in 10 patients. All planar bone scan images demonstrated normal findings, except one, SPECT images demonstrated normal findings in 11 vertebral hemangioma less than 3 cm in diameter. Three of four vertebral hemangioma that were 3 cm or larger showed abnormally increased or decreased uptake on SPECT images. There was a disparity between SPECT imaging and MRI.     

Circulation liquid velocity,gas holdup and volumetric oxygen transfer coefficient in external-loop airlift reactors

The effects of the horizontal connection length (0.1 ± L_e ± 0.5 m), the cross-sectional area ratio of downcomer-to-riser (0.11 ± A_d/A_r± 0.53), and the superficial gas velocity on gas phase holdups in the riser and downcomer were studied. The circulation liquid velocity, the mixing performance and the volumetric mass transfer coefficient in the external-loop airlift reactors were also measured. The horizontal connection length and A_d/A_r were major parameters which strongly affected the performance of external-loop airlift reactors. Useful correlations in the external-loop airlift reactors were obtained for gas holdups, the volumetric mass transfer coefficient, the circulation liquid velocity, and the mixing time.     

Suppression of natural killer cell activity in mouse spleen lymphocytes by several dopamine receptor antagonists

Glomerular diseases are associated with changes in glomerular membrane permeability properties that alter filtration rate of plasma water and barrier function of the capillary wall. To estimate intrinsic permeability properties that regulate transmembrane transport of water and macromolecules, theoretical analysis of renal clearance of tracer molecules can be used. The development of adequate theoretical models is required to achieve sufficient accuracy to simulate complicated biological processes. Current research in this area is aimed at improving and validating the presently available models in order to characterize the nature of permeability changes associated with pathological conditions. This is a key step in understanding the pathophysiological nature of glomerular diseases and in the development of effective treatments.     

Robust adaptive beamforming based on the eigenstructure method

In a linearly constrained beamformer with imperfect arrays, the authors investigate the cause of cancelling the desired signal from a viewpoint based on the eigenstructure properties of the array covariance matrix. Based on this cause, they propose a robust beamforming algorithm. As an adaptive algorithm of the proposed beamformer, the present a data-domain signal subspace updating algorithm     

The effect of quenching media on the heat transfer coefficient of polycrystalline alumina

Surface heat transfer coefficient values were measured for polycrystalline alumina quenched into water, into oil, and into liquid nitrogen. Since the measurements of the surface heat transfer coefficient h for alumina (and ceramics in general) are very limited, we compare our measurements with calculations of h for the water quench and with measurements of h on non-ceramic materials for the oil and liquid nitrogen quenches.     

Bioinformatics and its role in the study of the evolution and probiotic potential of lactic acid bacteria

Food Science and Biotechnology - Due to their numerous well-established applications in the food industry, there have been many studies regarding the adaptation and evolution of lactic acid...     

Enhanced surface morphology and transport property of poly(N‐vinylcarbazole)/gold nanocomposite Langmuir–Schaefer films

A composite of poly(N‐vinylcarbazole) (PVK) containing gold nanoparticles (GNPs) was synthesized via simple solid‐state in situ bulk polymerization of N‐vinylcarbazole in the presence of GNPs at a high temperature. Both PVK and PVK–GNP composites were characterized by Fourier transform infrared (FTIR) and UV–vis spectroscopy. The surface morphology of the composites was studied by scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy, and transmission electron microscopy (TEM). Thermal stability was identified via thermogravimetric analysis. The composites were fabricated into films using the Langmuir–Schaefer process. The enhancement in the characteristics of room temperature I–V, pressure–area isotherms, and photoelectrochemical behaviors was observed in the composite films. Results suggest that a charge transfer process occurs across the hybrid at the interface of the PVK–GNP composites. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers     

Effect of fermentation temperature on the microbial and physicochemical properties of silver carp sausages inoculated with Pediococcus pentosaceus

The effect of fermentation with Pediococcus pentosaceus at different temperatures ranging from 15 to 37 °C on the quality characteristics of silver carp sausages was investigated. Higher temperature stimulated the rapid growth of lactic acid bacteria, resulting in a rapid decline in pH, and consequently suppressed the growth of Pseudomonas, Micrococcaceae and Enterobacteriaceae. However, increasing fermentation temperature gave a progressive increase in total volatile basic nitrogen and biogenic amines in fermented silver carp sausages. Histamine was the main biogenic amine, exceeding 100 mg/kg after 48 h of fermentation at temperatures above 30 °C. Higher content of non-protein nitrogen and α-amino nitrogen correlated with the electrophoretic studies, which showed that proteolysis of high molecular weight myofibrillar and sarcoplasmic proteins was more prominent at higher fermentation temperatures. Products fermented at 23–30 °C showed greatest consumer preference and most favourable textural properties.     

Determination of coffee origins by integrated metabolomic approach of combining multiple analytical data

The flavor and taste of coffee are the most important criteria for evaluating its quality and they are influenced by environmental as well as genetic factors. Because of these factors, including soil, climate and species, diverse components of coffee have been developed. To observe the variation of coffee components by region, a metabolomic approach was applied. In this study, 21 coffee samples of different origin were analyzed by various measuring devices. The acquired data was then integrated and processed by principal component analysis (PCA) using SAS 9.1 software. We found that we could successfully identify the origins of the coffee, dividing the samples in the regions of Asia, South America, and Africa, using the integrated metabolomic approach of combining diverse analytical data with multivariate analysis. In particular, the enhancement of subtle differences by combining data from several instruments resulted in the accurate discrimination of coffee origins.