Effect of dietary docosahexaenoic acid on desaturation and uptake in vivo of isotope-labeled oleic, linoleic, and linolenic acids by male subjects

The effect of dietary docosahexaenoic acid (22∶6n−3, DHA) on the metabolism of oleic, linoleic, and linolenic acids was investigated in male subjects (n=6) confined to a metabolic unit and fed diets containing 6.5 or <0.1 g/d of DHA for 90 d. At the end of the diet period, the subjects were fed a mixture of deuterated triglycerides containing 18∶1n−9[d6], 18∶2n−6[d2], and 18∶3n−3[d4]. Blood samples were drawn at 0, 2, 4, 6, 8, 12, 24, 48, and 72 h. Methyl esters of plasma total lipids, triglycerides, phospholipids, and cholesterol esters were analyzed by gas chromatography-mass spectrometry. Chylomicron triglyceride results show that the deuterated fatty acids were equally well absorbed and diet did not influence absorption. Compared to the low-DHA diet (LO-DHA), clearance of the labeled fatty acids from chylomicron triglycerides was modestly higher for subjects fed the high DHA diet (HI-DHA). DHA supplementation significantly reduced the concentrations of most n-6[d2] and n-3[d4] long-chain fatty acid (LCFA) metabolites in plasma lipids. Accumulation of 20∶5n−3[d4] and 22∶6n−3[d4] was depressed by 76 and 88%, respectively. Accumulations of 20∶3n−6[d2] and 20∶4n−6[d2] were both decreased by 72%. No effect of diet was observed on acyltransferase selectivity or on uptake and clearance of 18∶1n−9[d6], 18∶2n−6[d2], and 18∶3n−3[d4]. The results indicate that accumulation of n−3 LCFA metabolites synthesized from 18∶3n−3 in typical U.S. diets would be reduced from about 120 to 30 mg/d by supplementation with 6.5 g/d of DHA. Accumulation of n−6 LCFA metabolites synthesized from 18∶2n−6 in U.S. diets is estimated to be reduced from about 800 to 180 mg/d. This decrease is two to three times the amount of n−6 LCFA in a typical U.S. diet. These results support the hypothesis that health benefits associated with DHA supplementation are the combined result of reduced accretion of n−6 LCFA metabolites and an increase in n−3 LCFA levels in tissue lipids.     

The impact of inspection reports on consumer behavior: A pilot study

This pilot study evaluated the impact of inspection score information on consumer behavior. Protection motivation theory was used to investigate consumer’s behavioral intentions resulting from food safety information provided in the questionnaire. The questionnaire was created to measure consumers’ perceived likelihood of changing behavior based on protection motivation theory after reading restaurant food safety information in the form of inspection reports. The pilot showed that the methodology used to collect the data was sound. While the number of respondents was too small to show significance, several important trends were noted. One of the more important finding was that the affordable cost of selecting an alternative restaurant rose with the number of violations.     

Comparative assessment of pest management practices in potato production at Farmer Field Schools

Farmer field schools (FFS) and other participatory approaches are useful methods for rapid delivery of agricultural technologies, knowledge, and information in resource-constrained agro-ecosystems. Cultivar selection, weekly fungicide applications and integrated disease management (IDM) based on a disease monitoring strategy were evaluated at FFS for late blight control. Farmers’ knowledge and perceptions of pest management and agronomic practices were also assessed for both FFS participants and non-participants from 1999–2002. Late blight development and tuber yield varied among field schools, but cultivars had significant effects on late blight severity and yield over a range of disease management options relative to the untreated check. FFS participants and non-participants used diverse sources of pest management information, but differed significantly (P?<?0.05) in their use of management methods and practices. Cultivar resistance and fungicides were ranked as major components of pest control by 18%–85% and 7%–30% of FFS participants and non-participants, respectively. Differences in knowledge of cropping practices and pest biology, causal agents, disease symptoms, factors favoring disease development and cultural management of insects and storage pests were recorded. Participatory field experiments, access to resistant cultivars, disease management and use of various agronomic practices learnt at FFS can greatly improve pest control and potato production.     

Application of out-of-step relaying for small generators in distributed generation

The recent popularity of distributed generation (DG) has caused an increasing number of small generators (rated between 100 kVA and 12.5 MVA) to be connected to the power system at the distribution level (480 V to 12.47 kV). Some utilities require that out-of-step relays be installed by the generation owner at the point of common coupling (PCC). This paper will examine out-of-step relaying practices as they apply to small generation protection. It will consider the value, purpose, and applicability and provide guidelines for setting of this type of relay when employed.     

The new science of protective relaying in the petrochemicalindustry

The multifunction digital relay has greatly expanded the science of protective relaying. The new science of protective relaying has resulted in the following improvements and benefits to the petrochemical industry. The multifunction relays typically have a large array of functions that can be used for electrical equipment protection. The multifunction relays are typically less costly than the equivalent package of discrete electromechanical and solid state relays. The programming logic provided by most multifunction relays allows for sophisticated protection schemes that were either not possible or economical with the discrete protection components of the past. The burden requirements of the multifunction relays are typically very low. With increases in technology, the testing and calibration of protective relays is changing. Advances in technology in the future may result in a decreased life expectancy of protective relay packages of the future     

Use of ozone to reduce molds in a cheese ripening room

Cheese ripening rooms have an unusual environment, an environment that encourages mold growth. Ozone has been applied in various ways in the food industry. One useful advantage of ozone is that it inactivates molds. In this study, a cheese ripening room was ozonated, and the effectiveness of this treatment was evaluated both in air and on surfaces through sampling on a weekly basis over a 3-month period. The results obtained indicate that ozone treatment reduced the viable airborne mold load but did not affect viable mold on surfaces. Only by wiping the surfaces with a commercial sanitizer was it possible to decrease the viable mold load on surfaces. To improve overall hygiene in the ripening room, a combination of cleaning regimes is recommended. The mold genera occurring most frequently in the air of the cheese ripening room were Penicillium, Cladosporium, and Aspergillus, which accounted for 89.9% of the mold isolates. Penicillium and Aspergillus were identified to the species level, and data showed that P. brevicompactum and P. aurantiogriseum, as well as A. versicolor, were the species most frequently isolated.     

Sensitivity of water quality indicators in a large tropical reservoir to selected climate and land‐use changes

This study compared the sensitivity of water quality in tropical Aguamilpa Reservoir, as represented by normalized algae mass and dissolved oxygen, to selected projected changes from global climate change and development. The sensitivity of reservoir stratification as an indicator of reservoir sensitivity also was analysed. Model simulations indicated the reservoir was more sensitive to changes during the warm‐dry season than at other times. Both indexes (normalized algal mass and dissolved oxygen mass) were more sensitive to changes in air temperature (climate change) and nitrogen loading (development) than to changes in flow. The sensitivity to air temperature was similar to, but generally less than, the sensitivity to nutrient inflow. At the bounding values for change (3 °C for temperature; 50% increase in nitrogen loading), the algae mass sensitivities were 0.15 mg L^?1 per 3 °C and 0.2 mg L^?1 per 50% nitrogen load increase, and the dissolved oxygen mass sensitivities were 0.7 mg L^?1 per 3 °C and 2.0 mg L^?1 per 50% load increase. Changes in air temperature and nitrogen loadings affect the reservoir in different ways, air temperature mostly changing the timing of the algal growth with little change in peak values, while nutrient loadings change the peak values with little change in the timing. While the sensitivities are similar, the total algal mass change is significantly larger for nitrogen loading, compared to air temperature changes. These results imply global climate change effects can be partially mitigated by implementing management measures in the surrounding watersheds to minimize nutrient inflows, especially nitrogen in the case of Aguamilpa Reservoir.     

Quantitative contamination and transfer of Escherichia coli from foods by houseflies, Musca domestica L. (Diptera: Muscidae)

The housefly, Musca domestica L. (Diptera: Muscidae), is recognized as an important factor in the dissemination of various infectious diseases such as cholera, shigellosis, and salmonellosis. They can also serve as a cross-contamination vector for other foodborne pathogens. However, the potential for bacterial transfer by houseflies has been demonstrated in a qualitative rather than quantitative manner. In this study, the numbers of bacteria a housefly can carry on its body and transfer to a clean surface after exposure to a sugar-milk aqueous solution, steak, and potato salad contaminated with a fluorescent gene Escherichia coli (8 log10 CFU/ml) were determined. In the first series of experiments to quantify bacterial numbers on the flies, about 40-60 flies were transferred into a sterile cage, exposed to the food for 30 min, the flies immobilized and the attached E. coli on each fly enumerated. Detectable E. coli (>1.7 log10 CFU/fly) were found on 43% (29/67), 53% (23/43), and 62% (32/52) of the flies in the cages with sugar/milk, steak, and potato salad, respectively. For the positive flies, the geometric mean carriage (log10 CFU/fly) was 2.93+/-1.24 for sugar-milk, 3.77+/-1.28 for steak, and 2.25+/-0.64 for the potato salad. In the second series of experiments, the transfer of bacteria by individual flies from contaminated food to the inner surface of a sterile jar per each landing was determined. E. coli transferred from the sugar-milk was 3.5+/-0.7 log10 CFU/fly-landing, 3.9+/-0.7 for steak and 2.61+/-1.16 for the potato salad. From the initial contamination levels of bacteria and the number of transferred bacteria, it can be calculated that flies contaminate clean surfaces with approximately 0.1 mg of food per landing.