Dietary manipulation of muscle long-chain omega-3 and omega-6 fatty acids and sensory properties of lamb meat

The effects of dietary manipulation of muscle long-chain omega-3 fatty acids (FA) on sensory properties of cooked meat in second cross ([Merino×Border Leicester]×Poll Dorset) wether lambs were evaluated. Lambs fed dietary supplements of fish meal (FM, Exp. 1) and fish oil (FO, Exp. 2) showed moderately (P<0.01) and markedly (P<0.001) increased muscle long-chain omega-3 FA content compared with those fed the basal diet of lucerne chaff and oat chaff. Protected canola seed (PCS, Exp. 1) significantly (P<0.001) increased omega-6 FA content of the longissimus muscle. In each of the 2 experiments (1 and 2), after being fed experimental diets for 6 weeks lambs were slaughtered at a commercial abattoir. At 24 h post-mortem (PM) the semitendinosus and biceps femoris muscles were removed from animals and stored at -20°C until evaluation of sensory properties using experienced panel members. The muscle samples were stored for 3 (Exp. 1) and 12 (Exp. 2) months then removed, thawed and cooked for sensory evaluation. The meat samples were cooked under standardized conditions in a convection microwave at 180°C (20-25 min) to an internal temperature of 75°C. Cooked samples were tested for flavour, aroma, juiciness and overall palatability. The significant increase in muscle long-chain omega-3 with FM (Exp. 1 and 2) and FO (Exp. 2) or omega-6 FA with PCS (Exp. 1) were not detrimental to sensory panel evaluations of flavour or aroma of cooked meat when compared with the basal diet. However, meat from FM (Exp. 1) had lower juiciness and FO (Exp. 2) had lower overall palatability. Protected sunflower meal protein with FO (Exp. 2) significantly lowered ratings for flavour, juiciness and overall palatability. Lamb meat with increased levels of long-chain omega-3 FA can be produced without altering the sensory quality (flavour or aroma) of the cooked meat.     

Empirical analysis of the intrinsic–extrinsic distinction of judgments of learning (JOLs): Effects of relatedness and serial position on JOLs.

A. Koriat's (1997) cue-utilization framework provided a significant advance in understanding how people make judgments of learning (JOLs). A major distinction is made between intrinsic and extrinsic cues. JOLs are predicted to be sensitive to intrinsic cues (e.g., item relatedness) and less sensitive to extrinsic cues (e.g., serial position) because JOLs are comparative across items in a list. The authors evaluated predictions by having people make JOLs after studying either related (poker flush) or unrelated (dog-spoon) items. Although some outcomes confirmed these predictions, others could not be readily explained by the framework. Namely, relatedness influenced JOLs even when manipulated between participants, primacy effects were evident on JOLs, and the order in which blocks of items were presented (either all related items first or all unrelated items first) influenced JOLs. The authors discuss the framework in relation to these and other outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Control of Histamine‐Producing Bacteria and Histamine Formation in Fish Muscle by Trisodium Phosphate

Scombrotoxin fish poisoning remains the primary cause of seafood poisoning outbreaks despite preventive guidelines. The purpose of this study was to investigate the use of pH for the control of growth and histamine formation by histamine‐producing bacteria in fish muscle. We examined pH effects on growth and histamine formation in tuna fish infusion broth and in inoculated tuna and mahi‐mahi fish muscle. Histamine production was significantly less for all bacterial strains at pH 8.5 compared to pH 5.5 in tuna fish infusion broth with no significant difference in growth. Elevated pH due to phosphate treatment of fish muscle tissues significantly reduced histamine formation with no effect on the growth of histamine‐producing bacteria. This study revealed that phosphate treatment of mahi‐mahi and tuna fish muscle resulted in significantly lower histamine production over 4 d of storage at 10 °C. Phosphate treatment of fish muscle may serve as a secondary barrier in addition to FDA recommended time and temperature controls for reducing public health concerns of scombrotoxin fish poisoning.     

Long-term recovery of PCB-contaminated sediments at the Lake Hartwell superfund site: PCB dechlorination. 1. End-member characterization

Under anaerobic conditions, such as those typically found in buried sediments, the primary metabolic pathway for polychlorinated biphenyls (PCBs) is reductive dechlorination in which chlorine removal and substitution with hydrogen by bacteria result in a reduced organic compound with fewer chlorines. Vertical sediment cores were collected from Lake Hartwell (Pickens County, SC) and analyzed in 5-cm intervals for 107 PCB congeners in a total of more than 280 samples from 18 sediment cores and surface samples. This paper reports on extensive PCB dechlorination measured in Lake Hartwell sediments and the characterization of dechlorination end-member (EM) patterns using chemical forensic methods. PCB congener fingerprinting and a multivariate receptor modeling method, polytopic vector analysis (PVA), were used for identification and characterization of weathered and dechlorinated PCB congener patterns. Dechlorination resulted in a substantial shift in buried sediments from tetra- through decachlorobiphenyl congeners to mono- through trichlorobiphenyl congeners. Mono- through trichlorobiphenyls comprised approximately 80% of the PCBs in buried sediments that underwent maximum dechlorination as compared to approximately 20% in surface sediments. The major concentration decreases were seen in the tetra- through hexachlorobiphenyl homologues, which accounted for over 90% of the dechlorination. Octa- through decachlorobiphenyl congeners also were dechlorinated, but their overall contribution to dechlorination was relatively small due to their low initial concentrations (< 5%). The net accumulation of 2-CB, 2,2'/2,6-DCBs, 2,4'-DCB, 2,2',4-TCB, and 2,2',6-TCB at Lake Hartwell matched characteristic PCB dechlorination products reported in the literature, such as those for Processes M, Q, and C; and the persistence of tetrachlorobiphenyls (TeCBs) that contained 24- and 25-congener groups resembled dechlorination Processes H or H'. Although dechlorination tended to be very extensive in most of the cores, it was not always consistent from core to core or at various depth intervals within a single core. The reason for this variability in dechlorination extent could not be determined from the existing data and did not appear to correlate with such factors as PCB concentration, total organic carbon, or age. The authors used fingerprinting analysis and a PVA multivariate receptor model as exploratory data analysis tools to characterize PCB sources and their alteration patterns. Dominant sources and alteration patterns were determined in this large data set by comparing PVA EM patterns with known source patterns (i.e., Aroclors or Aroclor mixtures) and literature-reported alteration patterns. PVA also afforded an opportunity to characterize the vertical and lateral distributions of the weathered and unweathered PCB source patterns and dechlorination patterns, a task that would have been much more difficult to accomplish through comparison of chromatograms alone.     

澳大利亚的摩天轮

澳大利亚墨尔本海边城市开发区的南星观象摩天轮高120m．建筑技术相当先进，2008年下半年完工后，将是南半球最大的摩天轮。     

水平定向钻进帮助新南威尔士扩大自来水供应

本文简要介绍了在Shannon Creek的储存设施工程采用水平定向钻进施工的情况。     

Estimating urban trail traffic: Methods for existing and proposed trails

The paper presents findings from the most comprehensive, continuous trail monitoring system in the United States, a network of 30 infrared monitors on five multiuse trails in Indianapolis, Indiana operating for periods of one to more than four years. We describe variation in traffic across different trails and segments of individual trails and present traffic ratios that describe variations in traffic by month, day of week, and time of day. We also present regression models for estimating traffic from temporal, weather, socio-demographic, and urban form variables. We propose and validate procedures for use of traffic ratios to extrapolate hourly counts to annual estimates and use of regression models to estimate traffic. Our procedures provide estimates within 20–30% of actual counts. Limitations of the models are noted. Potential applications range from forecasting traffic on proposed new trails to assessing the need for safety improvements such as stop lights at intersections.     

Parallel implementation of synthetic aperture radar algorithms

Two sequences of operations necessary for implementation of high resolution image formation in strip and spotlight modes of the synthetic aperture radar (SAR) are presented. The sequences are mapped onto a mesh-connected SIMD architecture. The mapping includes not only parallel implementation of all the basic computation steps, but also all the necessary data transformation and communication operations. Detailed estimates of the processing times are provided for Hughes Research Laboratories Systolic/Cellular architecture.This work was partially supported by NSF grant No MIP-8714689     

Refractive‐index matching between liquid crystals and photopolymers

Abstract— Refractive indices of two photocurable polymers, NOA65 and NOA81 (Norland Optical Adhesive), and two series of Merck liquid crystals, E‐series (E44, E48, and E7) and BL‐series (BL038, BL003 and BL006), and two UCF high‐birefringence liquid‐crystal mixtures were measured using an Abbe refractometer in the visible spectral region and 15–55°C temperature range. Some liquid crystals have excellent index matching with NOA65 in the red, while some fit better in the blue spectral region. To validate this index‐matching property found in the material level, we prepared some polymer‐dispersed liquid‐crystal devices. Good correlations between material and device performances are obtained.     

Listen while you work? Quasi-experimental relations between personal-stereo headset use and employee work responses.

Using a quasi-experimental design, this study examined relations between stereo headset use and employee work responses. Employees (N?=?256) worked on 32 jobs in an office of a retail organization. Employees indicated whether they were interested in using stereos at work. From those expressing an interest, a random sample (n?=?75) was assigned to a stereo condition. These employees used headsets at work for 4 weeks. The remaining employees (n?=?181) were assigned to a control condition and were not allowed to use stereos. Results indicated that employees in the stereo condition exhibited significant improvements in performance, turnover intentions, organization satisfaction, mood states, and other responses. The mood state of relaxation best explained the relation between stereo use and performance. Finally, employees in relatively simple jobs responded most positively to the stereos. (PsycINFO Database Record (c) 2010 APA, all rights reserved)