Control of Clostridium perfringens spores by green tea leaf extracts during cooling of cooked ground beef, chicken, and pork

We investigated the inhibition of Clostridium perfringens spore germination and outgrowth by two green tea extracts with low (green tea leaf powder [GTL]; 141 mg of total catechins per g of green tea extract) and high (green tea leaf extract [GTE]; 697 mg of total catechins per g of extract) catechin levels during abusive chilling of retail cooked ground beef, chicken, and pork. Green tea extracts were mixed into the thawed beef, chicken, and pork at concentrations of 0.5, 1.0, and 2.0% (wt/ wt), along with a heat-activated (75 degrees C for 20 min) three-strain spore cocktail to obtain a final concentration of approximately 3 log spores per g. Samples (5 g) of the ground beef, chicken, and pork were then vacuum packaged and cooked to 71 degrees C for 1 h in a temperature-controlled water bath. Thereafter, the products were cooled from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h, resulting in significant increases (P < 0.05) in the germination and outgrowth of C. perfringens populations in the ground beef, chicken, and pork control samples without GTL or GTE. Supplementation with 0.5 to 2% levels of GTL did not inhibit C. perfringens growth from spores. In contrast, the addition of 0.5 to 2% levels of GTE to beef, chicken, and pork resulted in a concentration-and time-dependent inhibition of C. perfringens growth from spores. At a 2% level of GTE, a significant (P < 0.05) inhibition of growth occurred at all chill rates for cooked ground beef, chicken, and pork. These results suggest that widely consumed catechins from green tea can reduce the potential risk of C. perfringens spore germination and outgrowth during abusive cooling from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h of cooling for ground beef, chicken, and pork.     

Triple‐junction effect and its electric field relaxation in three dielectrics

This paper analyzes the electric field distribution near a wedge‐like edge in arrangements consisting of three dielectrics using analytical and numerical methods. The electric potential behaves exponentially as rⁿ (r is the distance from the edge) near the edge, leading to an infinitely high field with decreasing r for all cases. The value of the analytically derived exponent n agreed well with that obtained from the numerical field calculations. It has also been demonstrated that rounded contact of the spacer with a zero contact angle can make the electric field constant without showing an exponential rise near the edge. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(1): 1– 8, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20670     

Crystal Growth of Thiol-Stabilized Gold Nanoparticles by Heat-Induced Coalescence

A monolayer of dodecanethiol-stabilized gold nanoparticles changed into two-dimensional and three-dimensional self-organized structures by annealing at 323 K. Subsequent crystal growth of gold nanoparticles occurred. Thiol molecules, although chemisorbed, form relatively unstable bonds with the gold surface; a few thiols desorbed from the surface and oxidized to disulfides at 323 K, because the interaction energy between thiol macromolecules is larger than that between a thiol and a nanoparticle. The gold nanoparticles approached each other and grew into large single or twinned crystals because of the van der Waals attraction and the heat generated by the exothermic formation of disulfides.     

Correction of instrument measurement data for improving the visual color match between monitor and hardcopy

Abstract— Soft proofing, which can confirm the color reproduction of printed matter on a monitor, is coming into wide use in the field of graphic arts. However, there is a problem in that the color on the monitor looks different from that of printed matter, even though the L*a*b* value of the monitor's white point has been adjusted to that of the paper by using a spectroradiometer. After the color rendition of an LCD is visually adjusted to that of the paper, the measured color of the LCD shows color with L*a*b* values corresponding to a more greenish‐blue white than that of paper. For CRTs, this corresponds to a more bluish‐white. In this paper, it was assumed that bright lines in the measured spectrums of the monitors and the illuminations spread to the next wavelength band by the optical systems of the spectroradiometer. To solve the problem, a method is proposed to enhance the bright line by using a three‐tap digital filter. The effect of this method on two types of monitors under three types of illumination is also reported. After enhancing the bright lines, ΔE between the monitor and paper becomes smaller than that for the original one.     

Urgent coronary artery bypass surgery by only arterial graft for acute myocardial infarction

The authors conducted urgent coronary artery bypass grafting (CABG) using only arterial graft for mild and moderate acute myocardial infarction (AMI) in 9 cases from January, 1995 through December, 1996. Mild and moderate AMI means free from cardiogenic shock by catecholamines alone or catecholamines and intra aortic balloon pumping (IABP). The period from the onset of AMI to admission was 2-24 (average 8 +/- 6) hours. Coronary arteriography (CAG) was performed immediately following admission. CABG was done immediately after CAG. CPK-MB on admission was 14-184 (average 67 +/- 61) IU/l. Three cases were main trunk disease over 90% stenosis, three cases were main trunk disease equivalent if another stenotic lesion over 99% were occluded, three cases would fall into cardiogenic shock if another stenotic lesion over 99% were occluded. Postoperative IABP was necessary for three cases. No case required repetition of IABP. For minimal operation time and to attain high graft flow, saphenous vein (SV) graft are generally used for emergencies. CABG was conducted here using only arterial graft (Mean anastomosis number was 2.3). There were 8 RITA grafts, 9 LITA grafts, and 4 RGEA grafts. Post operative CAG showed all the grafts to be patent, but string sign was noted for two LITA grafts. Prognosis was favorable in all cases. We could conduct urgent CABG surgery safely for mild and moderate AMI using only arterial grafts.     

Deep-submicrometer BiCMOS circuit technology for sub-10-ns ECL 4-MbDRAM's

A 0.3-μm sub-10-ns ECL 4-Mb BiCMOS DRAM design is described. The results obtained are: (1) a V_cc connection limiter with a BiCMOS output circuit is chosen due to ease of design, excellent device reliability and layout area; (2) a mostly CMOS periphery with a specific bipolar use provides better performances at high speed and low power; (3) the direct sensing scheme of a single-stage MOS preamplifier combined with a bipolar main amplifier offers high speed; and (4) the strict control of MOS transistor parameters has been proven to be more important in obtaining high speed DRAMs, based on the 4-Mb design     

Rapid Reconstitution of Biosynthetic Machinery for Fungal Metabolites in Aspergillus oryzae: Total Biosynthesis of Aflatrem

Reconstitution of the biosynthetic machinery for fungal secondary metabolites in Aspergillus oryzae provides an opportunity both for stepwise determination of the biosynthetic pathways and the total biosynthesis of fungal natural products. However, to maximize the utility of the reconstitution system, a simple and rapid strategy for the introduction of heterologous genes into A. oryzae is required. In this study, we demonstrated an effective method for introducing multiple genes involved in the biosynthesis of fungal metabolites by using the expression vectors pUARA2 and pUSA2, each of which contains two cloning sites. The successful introduction of all the aflatrem biosynthetic genes (seven genes in total) after two rounds of transformation enabled the total biosynthesis of aflatrem. This rapid reconstitution strategy will facilitate the functional analysis of the biosynthetic machinery of fungal metabolites.     

Tensile fatigue behaviour of ultra-high performance fibre reinforced concrete (UHPFRC)

The tensile fatigue behaviour of ultra-high performance fibre reinforced concrete (UHPFRC) under constant amplitude fatigue cycles is presented. Three series of uniaxial tensile fatigue tests up to a maximum of 10 million cycles were conducted with the objective to determine the endurance limit of UHPFRC that was supposed to exist for this material. The fatigue tests reveal that an endurance limit exists in all three domains of UHPFRC tensile behaviour at S-ratios ranging from 0.70 to 0.45 with S being the ratio of the maximum fatigue stress to the elastic limit strength of UHPFRC. Rather large variation in local specimen deformations indicates significant stress and deformation redistribution capacity of the UHPFRC bulk material enhancing the fatigue behaviour. The fatigue fracture surface of UHPFRC shows features of the fatigue fracture surfaces of steel, i.e. fatigue crack propagation is identified by a smooth surface while final fracture leads to rather rough surface. Various fatigue damaging mechanisms due to fretting and grinding as well as tribocorrosion are identified.