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91.
92.
ALONZO A. GABRIEL KRISTELLE GAY S. CRUZ JEANE AUBREY D. DE GUZMAN 《Journal of Food Processing and Preservation》2009,33(S1):136-144
The decimal reduction times (D values) of Escherichia coli (American Type Culture Collection 25922) were established in a young coconut endosperm beverage, a famous local drink in the Philippines and in many tropical countries. Artificially inoculated cells were heated to 60, 70 and 80C at various heating times prior to survivor enumeration by surface plating onto pre-solidified Eosine Methylene Blue Agar. Results showed that the surviving populations significantly (P < 0.05) decreased with increasing exposure time and temperature. The calculated D values ranged from 0.26 ± 0.01 to 0.56 ± 0.08 min. Validation of the results by establishing the thermal resistance of other E. coli isolates in the coconut beverage medium was recommended.
The study established the thermal inactivation rates of Escherichia coli (American Type Culture Collection 25922) in a young coconut endosperm beverage medium in various heating temperatures. The results obtained from this study may be used in the calculations of appropriate thermal process schedules for the test beverage against the test organism. 相似文献
PRACTICAL APPLICATION
The study established the thermal inactivation rates of Escherichia coli (American Type Culture Collection 25922) in a young coconut endosperm beverage medium in various heating temperatures. The results obtained from this study may be used in the calculations of appropriate thermal process schedules for the test beverage against the test organism. 相似文献
93.
PATRICIA L. ALVES DE LIMA DANIEL A RIBEIRO MARINA M SUGUI ANA PAULA TEREZAN MARIA APARECIDA C DOMINGUES E R FILHO LUCIANA AZEVEDO DAISY M F SALVADORI LUCIA R RIBEIRO 《Journal of Food Biochemistry》2010,34(1):206-228
In this study, we have investigated the stability of the antigenotoxic properties of dried of Lentinula edodes (Berk.) Singer mushroom powder stored at room and at − 20C. Mice were pretreated by gavage for 15 consecutive days with 0.6 mL/day of an aqueous extract of dried L. edodes powder prepared at 60C. On day 15, the mice were intraperitoneally injected with 50 mg/kg N-ethyl-N-nitrosourea (ENU); 3 h later, peripheral blood was withdrawn from the animals and used to evaluate DNA damage using the comet assay. The mice were sacrificed 24 h after the ENU treatment and the bone marrow used to measure the frequency of micronucleated polychromatic erythrocytes. The results indicated that storage at both room temperature and at − 20C significantly reduced the antigenotoxic effects of the mushroom powder. In addition, whereas freshly dried mushroom powder was nongenotoxic, storage of the powder at − 20C resulted in genotoxic activity ( P < 0.05). Taken together, our data indicate that constituents of L. edodes powder are altered during storage, resulting in both genotoxicity and a reduction in antigenotoxicity. 相似文献
94.
95.
ABSTRACT This work presents a rotor resistance estimation algorithm. The estimation process is based on a recursive least squares method. It is applied to a speed sensorless induction motor drive scheme in order to implement slip adaptation. A discrete approach is considered in which an induction motor model written in form of difference equations is used by the estimation algorithm. All the associated mathematical developments are shown. Simulation results are used to verify the performance of the proposed rotor resistance estimator. 相似文献
96.
M. DE LA SEN 《International journal of control》2013,86(6):1769-1775
In this note, it is proved that stability of composite systems including parallel subsystems can be achieved for certain sets of initial conditions and additional stability assumptions for the non-hyperstable subsystems. It is required that at least one subsystem be asymptotically hyperstable. 相似文献
97.
CK Combs DE Johnson SB Cannady TM Lehman GE Landreth 《Canadian Metallurgical Quarterly》1999,19(3):928-939
Microglial interaction with amyloid fibrils in the brains of Alzheimer's and prion disease patients results in the inflammatory activation of these cells. We observed that primary microglial cultures and the THP-1 monocytic cell line are stimulated by fibrillar beta-amyloid and prion peptides to activate identical tyrosine kinase-dependent inflammatory signal transduction cascades. The tyrosine kinases Lyn and Syk are activated by the fibrillar peptides and initiate a signaling cascade resulting in a transient release of intracellular calcium that results in the activation of classical PKC and the recently described calcium-sensitive tyrosine kinase PYK2. Activation of the MAP kinases ERK1 and ERK2 follows as a subsequent downstream signaling event. We demonstrate that PYK2 is positioned downstream of Lyn, Syk, and PKC. PKC is a necessary intermediate required for ERK activation. Importantly, the signaling response elicited by beta-amyloid and prion fibrils leads to the production of neurotoxic products. We have demonstrated in a tissue culture model that conditioned media from beta-amyloid- and prion-stimulated microglia or from THP-1 monocytes are neurotoxic to mouse cortical neurons. This toxicity can be ameliorated by treating THP-1 cells with specific enzyme inhibitors that target various components of the signal transduction pathway linked to the inflammatory responses. 相似文献
98.
CA McGibbon DE Krebs CA Trahan SB Trippel RW Mann 《Canadian Metallurgical Quarterly》1999,14(1):52-58
The mitochondrial, inner-membrane-associated, reversible NADPH-->NAD transhydrogenase of adult Hymenolepis diminuta physiologically couples matrix-localized, NADP-specific "malic" enzyme with NADH-dependent anaerobic electron transport. Employing submitochondrial particles (SMP) as the source of enzyme activity and both spectrophotometric and fluorometric assessments, the present study made evident that in its catalysis of transhydrogenation between NADPH and NAD, the cestode enzyme engages in the concomitant transmembrane translocation of protons. As assessed spectrophotometrically, the catalysis of NADPH-dependent NAD reduction by H. diminuta SMP was stimulated significantly by carbonyl cyanide 3-chlorophenylhydrazone (CCCP), carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP), as well as by the protonophoric anthelmintic, niclosamide. In addition, N,N'-dicyclohexylcarbodiimide (DCCD) markedly diminished SMP-catalyzed hydride ion transfer between NADPH and NAD. The catalysis by SMP of concomitant, transhydrogenase-mediated proton translocation was evaluated more directly via fluorometric assays using 8-anilino-1-napthalenesulfonic acid (ANS) as the probe. These latter evaluations revealed a transhydrogenase-dependent enhancement of ANS fluorescence in accord with an intravesicular accumulation of protons. ANS fluorescence was quenched rapidly when the assay system was supplemented with CCCP, FCCP, or niclosamide. Consistent with the helminth transhydrogenase acting as a proton pump, transhydrogenase-mediated enhanced fluorescence also was inhibited by DCCD. Considered collectively, these data indicated, apparently for the first time for any invertebrate system, that the transhydrogenase, in catalyzing the NADPH-->NAD reaction, acts in the translocation of protons from the matrix to the intermembrane space mitochondrial compartment. 相似文献
99.
P Mooney M Sarmiento JM Bishop N Biswas NM Cason L Dauwe J Godfrey VP Kenney R Pemper E Rojek RC Ruchti WD Shephard G Ginther RM Edelstein CP Forsyth K Gamarnik AE Kreymer RJ Lipton JM McQuade DM Potter JS Russ L Spiegel DE Johnson D Buchholz LM Cremaldi SW Delchamps HS Mao JL Rosen W Sakumoto RA Schluter SB Sontz C Winter 《Canadian Metallurgical Quarterly》1989,39(9):2494-2498
100.
L Ohno-Machado JH Gennari SN Murphy NL Jain SW Tu DE Oliver E Pattison-Gordon RA Greenes EH Shortliffe GO Barnett 《Canadian Metallurgical Quarterly》1998,5(4):357-372
Carboxylate and sulfate groups were introduced at the surface of poly(ethylene) (PE) samples. This was accomplished by coating and immobilizing sodium 10-undecenoate (C11(:)) and 10-undecene sulfate (S11(:)) on the polymer by means of an argon plasma treatment. The composition of the coated surfactant layer was proportional to the composition of the coating solution. The thickness of the surfactant layer on the surface of PE samples, which were precoated from an aqueous solution with a total surfactant concentration of 0.30 M, was about 55 A. The presence of carboxylate and sulfate groups after plasma treatment of the precoated surfaces was confirmed by X-ray photoelectron spectroscopy (XPS). About 20% of the initial amount of functional groups of the coated surfactants was retained at the PE surface. The ratio of carboxylate/sulfate groups at the plasma treated surfaces was dependent on the composition of the precoated surfaces. The minimum surface density of these groups on the resulting samples was about one group per 40 A2. 相似文献