Inactivation of Escherichia coli and Listeria innocua in kiwifruit and pineapple juices by high hydrostatic pressure

Escherichia coli and Listeria innocua in kiwifruit and pineapple juices were exposed to high hydrostatic pressure (HHP) at 300 MPa for 5 min. Both bacteria showed equal resistance to HHP. Using low (0 degrees C) or sub-zero (-10 degrees C) temperatures instead of room temperature (20 degrees C) during pressurization did not change the effectiveness of HHP treatment on both bacteria in studied juices. Pulse pressure treatment (multiple pulses for a total holding time of 5 min at 300 MPa) instead of continuous (single pulse) treatment had no significant (p>0.05) effect on the microbial inactivation in kiwifruit juice; however, in pineapple juice pulse treatment, especially after 5 pulses, increased the inactivation significantly (p<0.05) for both bacteria. Following storage of pressure-treated (350 MPa, 20 degrees C for 60 s x 5 pulses) juices at 4, 20 and 37 degrees C up to 3 weeks, the level of microbial inactivation further increased and no injury recovery of the bacteria were detected. This work has shown that HHP treatment can be used to inactivate E. coli and L. innocua in kiwifruit and pineapple juices at lower pressure values at room temperature than the conditions used in commercial applications (>400 MPa). However, storage period and temperature should carefully be optimized to increase the safety of HHP treated fruit juices.     

The effect of aprotinin on extraneural scarring in peripheral nerve surgery: an experimental study

BACKGROUND: Although laser resurfacing has become increasingly popular in the treatment of Caucasian skin, concerns about healing and postinflammatory pigmentary changes have limited its use in Asian skin. OBJECTIVE: The purpose of this study was to determine the efficacy and safety of the Erbium(ER):YAG laser used in the treatment of Asian skin. METHODS: Fifty Asian individuals with Rhytids, scars, pigmentary alteration, and a variety of cutaneous growth were treated with the Erbium:YAG laser. Patients were evaluated for clinical efficacy, wound healing, post-operative erythema, and post-inflammatory pigmentary changes. RESULTS: Significant improvement was noted in all individuals. Shorter periods for re-epithelization and erythema duration were noted when compared to previously reported results following carbon dioxide laser resurfacing. CONCLUSION: The Erbium:YAG laser is safe and effective in the treatment of Asian skin.     

A fussy-logic control language for embedded controllers

Microcontrollers are being used in many commercial and consumer products to introduce a higher level of intelligence. There exist an opportunity and need to develop high-level languages to be used specifically in industrial product development. A recent trend in such embedded applications is the use of fuzzy-logic control. An ongoing project in the Industrial Research Laboratory at the University of Florida investigates the various aspects of microcontroller architectures, operating systems and languages. This report summarizes our progress in developing a fuzzy-logic control language for microcontrollers.     

Modeling and Predicting the Drying Kinetics of Apple and Pear: Application of the Weibull Model

Drying data of apple and pear at 40, 50, 60, 70, and 80°C were described by the Weibull model and it was observed that the shape parameter of the Weibull model did not depend on temperature. Therefore the reduced Weibull model with fixed shape parameter was proposed as the primary model to describe drying data with a slight loss of goodness-of-fit. Temperature dependence of time-parameter (time necessary to reduce the initial moisture ratio by 90%) could be described by two ad hoc models as the secondary models. Predictions using the integrated models almost perfectly agreed with the experimental drying data of apple at 45 and 65°C and of pear at 55 and 75°C, respectively. Kinetic analyses with published data have shown that the reduced Weibull model can also successfully be used to describe the drying data of certain fruits. Time-parameters tabulated in this study can be useful for food manufacturers.     

Microstructural analysis of an HT9 fuel assembly duct irradiated in FFTF to 155 dpa at 443 °C

The majority of data on the irradiation response of ferritic/martensitic steels has been derived from simple free-standing specimens irradiated in experimental assemblies under well-defined and near-constant conditions, while components of long-lived fuel assemblies are more complex in shape and will experience progressive changes in environmental conditions. To explore whether the resistance of HT9 to void swelling is maintained under more realistic operating conditions, the radiation-induced microstructure of an HT9 ferritic/martensitic hexagonal duct was examined following a six-year irradiation of a fuel assembly in the Fast Flux Test Reactor Facility (FFTF). The calculated irradiation exposure and average operating temperature of the duct at the location examined were ∼155 dpa at ∼443 °C. It was found that dislocation networks were predominantly composed of (a/2)<1 1 1> Burgers vectors. Surprisingly, for such a large irradiation dose, type a<1 0 0> interstitial loops were observed. Additionally, a high density of precipitation occurred. These two microstructural characteristics may have contributed to the rather low swelling level of 0.3%.     

Thermal and chemical inactivation of lactococcal bacteriophages

Ten lactococcal bacteriophages in M17 broth were treated by heat (72 °C, 15 min and 90 °C, 5 min), ethanol and isopropanol at concentrations of 10%, 50%, 75% and 100% (v/v). The heat treatments were not sufficient to inactivate all the bacteriophages studied whereas ethanol, which was also more efficient biocide than isopropanol, at a concentration of 75% could inactivate all the phages in 1 min. The 50% and 75% of ethanol were more effective than 100%, which was also observed for isopropanol. Survival curves’ deviations from linearity as sigmoidal shapes could be described via an empirical model with four parameters. The parameters of the model could be reduced from four to two with a slight loss of goodness-of-fit. The reduced model also provided good fit to describe the isopropanol inactivation kinetics of the phages at concentrations of 50% and 75%. This demonstration may also be a useful tool for further inactivation studies in which ethanol or other biocides are used with sufficient survival data points at selected time intervals. Although more studies should be carried out with different phages, this study confirmed the lethal effect of ethanol, commonly used to disinfect utensils and laboratory equipment, on lactoccocal bacteriophages.     

An exact reanalysis algorithm using incremental Cholesky factorization and its application to crack growth modeling

In this paper, an exact reanalysis algorithm based on an incremental Cholesky factorization is presented, which can solve a linear system of equations when a small portion of the coefficient matrix is modified. The efficiency of the proposed algorithm is demonstrated by modeling quasi‐static crack growth in the extended finite element method. The example presented shows that a 60% to 70% reduction in computational time is achievable by using the reanalysis approach for solving crack growth problems. It is shown that the reanalysis approach has increasing benefits as the mesh density increases. Copyright © 2012 John Wiley & Sons, Ltd.     

Moisture Distribution Changes and Wetwood Behavior in Subalpine Fir Wood during Drying Using High X-Ray Energy Industrial CT Scanner

In some species, such as subalpine fir (Abies lasiocarpa [Hook] Nutt), the water content of the confined zones in heartwood is as high as or greater than that of sapwood. Such wet zones of heartwood are referred to as “wetpocket” or “wetwood.” Wood products from subalpine fir forests are adversely affected by the wetwood-associated problems, particularly during the drying process. The objectives of the study were as follows: (1) to investigate feasibility of a high X-ray energy industrial computed tomography (ICT) scanner for imaging wetwood; and (2) to determine changes of the 2-D and 3-D moisture profiles (from core to shell) at different drying times.

Although medical CT scanning has been used for attaining signal intensity profiles of typical wood at different drying times, the technology has not, to date, been used for the study of wetwood phenomenon. This study presents, for the first time, results from the ICT imaging of the wetwood phenomenon. The results indicate that the ICT imaging system provides a powerful technique for imaging wetwood at different drying times. In addition, the results show that during the initial phase of drying, almost flat moisture profiles were observed in all wood types except for the wetwood, which showed a relatively higher moisture profile. A much slower (sluggish) drying development pattern at each increment from core to shell was found within the wetwood zone than normal wood regions along the width, thickness, and length of the board.     

Fatty acid composition of 19 species of fish from the black sea and the Marmara Sea

Evidence suggests that differences in fatty acid composition among various fish species may be due to differences in diet or to environmental factors such as temperature, salinity, and depth at which the fish are caught. The beneficial effects of a diet containing fish on cardiovascular or other diseases have been associated with their high content of eicosapentaenoic (20∶5n-3) and docosahexaenoic (22∶6n-3) acids. In this study we analyzed the fatty acid composition of the flesh of 18 different species of marine fish and of cultured rainbow trout. The fish were obtained from the Black and the Marmara Seas, both of which have unique biological and ecological systems as well as eutrophication and pollution. The contents of 20∶5n-3 and 22∶6n-3 in the marine fish ranged from 4.2 to 13.3 wt% of total fatty acids, and from 6.6 to 40.8 wt%, respectively. The most important differences from other studies on oceanic fish were the tendencies toward higher percentages of 16∶0 and 22∶6n-3. The n-3 series of polyunsaturated fatty acids were present as 32.4±1.9% of the total fatty acids. The present study suggests that mature and immature Pomatomus saltator, as well as Engraulis encrasicolus, Mullus surmuletus, Sardina pilchardus, Mugil cephalus, and Sarda sarda may be preferred for the Turkish diet as a result of their high 20∶5 n-3 and 22∶6 n-3 contents. The cultured rainbow trout Oncorhynchus mykiss is not as good a source of n-3 fatty acids as are the marine fish.