Drinking Water Treatment Options for Eliminating Freshwater Algae

A massive mixed algal growth may have many adverse effects on the water quality and causes acute problems, especially in different treatment steps for the production of drinking water. The effectiveness of drinking water treatment options for eliminating the nuisance created by River Nile water algae was the main objective of this study. The algal removal rate increased when using oxidants combined with alum-potassium permanganate; this was the most effective treatment combination for algal removal. When natural flocculant seeds of Moringa oleifera were used, the algal removal rate increased by more than 18% than that obtained by a chemical coagulant.     

Effect of ball mill grinding parameters of hydrated lime fine grinding on consumed energy

The influence of several grinding parameters such as charged material volume, ball filling ratio, and mill rotation speed on energy efficiency of fine grinding of hydrated lime and the product fineness of hydrated lime was studied experimentally using a laboratory scale ball mill. The product size and surface area of the ground samples were determined with respect to the above variables, and changes in energy input during the grinding were described in detailed. Finally, the optimum conditions for the grinding of the hydrated lime with the ball mill were obtained. The results from this study showed that the ball mill load and mill speed are the most important parameters rather than ball mill charged material volume for the fine grinding of the hydrated lime using the ball mill in terms of energy efficiency associated with external surfaces.     

Effect of Molecular Weight on Thermal Conductivity of Gases

A new formula has been developed to estimate thermal conductivity of hydrocarbon gases dependent on molecular weight of the range 20-100 and under temperatures ranging between 0 and 400°F. In this work an introduction of the available observed data develops a new correlation for the effect of molecular weight on the predication of thermal conductivity of gases.     

A framework for integrating manufacturing process design and analysis

Product design and evaluation requires a broad and varied set of information and analysis tools. Yet effective design and evaluation of a product during its design phase is critical if production costs are to be minimized. A system is described that integrates product design specifications with material and process databases, and a simulation-based analysis module. The system allows product designs to be evaluated in terms of economic and technical criteria, and to identify the best production environment.     

Design of selective M-channel perfect reconstruction FIR filterbanks

A new method is presented for the optimal design of M-channel perfect reconstruction FIR quadrature mirror filter (QMF) banks which is based on the orthogonal matrix concept. The parameters of the analysis filters are adjusted so that they have a linear phase and minimum stopband energy. Comparison with a recently published method reveals that the resulting design procedure gives better stopband characteristics. A numerical design example is included to validate the theory and to demonstrate the superiority of the designed filters from selectivity, reconstruction and distortion points of view     

Rupture of a presumed hydatid cyst of the interventricular septum diagnosed by transoesophageal echocardiography

In a sample of 34 study subjects, Cook and Jamshidi intraosseous (IO) needles were compared for ease of insertion into turkey bones. The averaged lapsed time of insertion was significantly shorter using the Jamshidi needle (25.5 v 56.2 seconds, P < .0001). The mean difficulty of insertion score was lower using the Jamshidi needle (3.0 v 7.1 on a 10-cm visual analog scale, P < .0001). The less costly Jamshidi needle is easier to use in IO insertion in this turkey bone model.     

Two Phase Flow Pressure Drop for the Coalescence of Secondary Dispersions in Ballotini Glass Particulate Beds

Steady state and unsteady state operation of ballotini glass particulate bed coalesces were studied for separation of oil-in-water secondary dispersions at constant temperature. The study was made of pressure drop during two-phase flow to determine the pressure drop characteristic of the porous media (i.e., spherical ballotini glass particulate beds) for coalescence. The main variables affecting the two-phase flow pressure drop are inlet drop size, properties of dispersed and continuous phases, superficial velocity, phase ratio, particle size, bed depth, bed material, packing arrangement, wettability of the packing, bed voidage or porosity, and sphericity or shape of particles.     

Suppression subtractive hybridization identifies bacterial genomic regions that are possibly involved in hBD-2 regulation by enterocytes

Scope: Human β‐defensin 2 (hBD‐2) is an inducible antimicrobial peptide synthesized by the epithelium to counteract bacterial adherence and invasion. It has been suggested that probiotic bacteria sustain gut barrier function via induction of defensins. The goals of this study were (i) to evaluate the potential immunomodulatory effects of 11 different Lactobacillus fermentum strains isolated from Kimere, an African fermented pearl millet (Pennisetum glaucum) dough, on the hBD‐2 secretion by human intestinal CaCo‐2 cell line and (ii) to examine genetic differences between two strains of L. fermentum (K2‐Lb4 and K11‐Lb3) which differed in their effect on the production of hBD‐2 in this study. Methods and results: Totally, 46 strains of L. fermentum from Kimere were isolated and characterized using molecular biology methods including pulsed‐field gel electrophoresis patterns. After performing time‐ and dose‐experiments, CaCo‐2 cells were incubated with or without bacteria for 12 h. L. fermentum PZ1162 was included as the positive control. Cell‐free supernatants were analyzed for hBD‐2 protein by enzyme‐linked immunosorbent assay (ELISA). To identify potential bacterial genes associated with hBD‐2 regulation, suppression subtractive hybridization (SSH) was used. Among the 11 strains tested, only two strains of bacteria, K11‐Lb3 and K2‐Lb6, significantly induced the production of hBD‐2 by CaCo‐2 cells. This effect was strain‐specific, dose‐dependent and particularly seems to be bacterial genomic‐dependent as manifested by SSH. L. fermentum strains with and without hBD‐2 inducing effect differed in genes encoding proteins involved in glycosylation of cell‐wall proteins e.g. glycosyltransferase, UDP‐N‐acetylglucosamine 2‐epimerase, rod shape‐determining protein MreC, lipoprotein precursors, sugar ABC transporters, and glutamine ABC transporter ATP‐binding protein. Conclusion: This study implies that certain strains of L. fermentum isolated from Kimere may stimulate the intestinal innate defense through the induction of hBD‐2. The molecular basis of hBD‐2 induction by L. fermentum strain K11‐Lb3 may be based on glycosylated cell‐surface structures synthesized with the aid of glycosyltransferase, UDP‐N‐acetylglucosamine 2‐epimerase, and rod shape‐determining protein MreC.     

Use of organic acids for the control of Clostridium perfringens in cooked vacuum-packaged restructured roast beef during an alternative cooling procedure

This study was conducted to determine how well Clostridium perfringens spores germinate and grow in restructured roast beef treated with different commercial organic salts during an alternative chilling procedure. The meat was prepared according to an industrial recipe (10% water, 1.5% sodium chloride, and 0.5% sodium triphosphate). The base meat was treated with sodium citrate at 2 or 4.8% (wt/wt), buffered to a pH of 5.6, 5.0, or 4.4 (six treatments); a 60% (wt/wt) solution of sodium lactate at 2 or 4.8% (wt/wt); sodium acetate at 0.25% (wt/wt); or sodium diacetate at 0.25% (wt/wt). Untreated meat was used as a control. Meat samples were inoculated with a three-strain cocktail of C. perfringens spores (strains ATCC 10388, NCTC 8238, and NCTC 8239). Meat was vacuum packaged in bags and cooked in a stirred water bath to an internal temperature of 75 degrees C for 20 min, and then the bags were cooled from 54.4 to 4.4 degrees C within 18 h. Samples were taken after inoculation, after cooking, and after chilling. Spore and vegetative cell counts were obtained after incubation at 37 degrees C for 8 to 10 h in Fung's Double Tubes containing tryptose sulfite agar without egg yolk enrichment. Cooking was not sufficient to eliminate C. perfringens spores. Over the 18-h cooling period, sodium citrate, sodium lactate, and sodium diacetate reduced the growth of C. perfringens to < 1 log unit, a growth level that meets U.S. Department of Agriculture performance standards. The use of sodium citrate or sodium lactate at a concentration of > or = 2% (wt/wt) inhibited C. perfringens growth over the 18-h cooling period.