Two Lipoxygenases from Germinated Barley-Heat and Kilning Stability

Using ammonium sulfate precipitation followed by hydrophobic and ion exchange chromatography, two lipoxygenase isoenzymes, LOX 1 and LOX 2, were 18.3- and 44.5-fold purified from germinated barley, with 18 and 24% recovery of activity respectively. LOX 1 and LOX 2 were characterized by isoelectric points 4.9 and 6.4, and molecular weights of 90 kd and 110 kd, respectively. Apparent Km values for linoleic acid were 0.06 mM for LOX 1 and 0.18 mM for LOX 2. LOX 1 converted linoleic acid to 9 and 13 hydroperoxides at about 4:1, whereas the 13 hydroperoxide was the major product formed by LOX 2 (ratio 3:7). For both isoforms, thermal inactivation data indicated first order kinetics with activation energies influenced by ionic strength and pH. Isoenzymes composition was analyzed for three kilning schemes: the 1:3 ratio between LOX 1 and LOX 2 observed in germinated barley increased during the course of kilning.     

Effect of Antioxidants on Malonaldehyde Production and Fatty Acid Composition in Pieces of Bovine Muscle and Adipose Tissue Stored Fresh and Frozen

TBA-reactive material was produced in pieces of bovine semitendinosus muscle and adipose tissue during storage at 2° 2°C and ?10° 2°C. The process was faster in muscle than in adipose tissue and the total content, higher at 2°C than at ?10°C. The effect of sprying butylated hydroxytoluene and a citric acid-EDTA-ascorbic acid mixture on the production of malonaldehyde was studied. Declines in both saturated and unsaturated fatty acid proportions of the polar lipids without increases in the content of free fatty acids suggests that enzymes involved in lipid catabolism remain active at low temperatures. Whereas lipid breakdown was unaffected, malonaldehyde production was inhibited by sprying antioxidants in early stages of the slaughtering process.     

Inhibition of Horse Bean and Germinated Barley Lipoxygenases by Some Phenolic Compounds

Phenolic compounds have been repeatedly implicated as potent antioxidants. Efficiency has been frequently estimated by radical scavenging activity and few reports have considered lipoxygenase (LOX) inhibition. Horse bean LOX was inhibited by a range of phenolic acids, gallates and flavonoids. All compounds tested were uncompetitive inhibitors with the exception of flavonol aglycons which were non competitive type. In each class of compounds, inhibition constants were strongly affected by structures. Inhibition patterns of (-)-epicatechin on germinated barley LOXs were detailed: (-)-epicatechin acted as an uncompetitive inhibitor while (-)-epicatechin reduced hydroperoxide formation by its radical scavenging activity and thus limited enzyme activation.     

Socialization in an Open Source Software Community: A Socio-Technical Analysis

Open Source Software (OSS) development is often characterized as a fundamentally new way to develop software. Past analyses and discussions, however, have treated OSS projects and their organization mostly as a static phenomenon. Consequently, we do not know how these communities of software developers are sustained and reproduced over time through the progressive integration of new members. To shed light on this issue I report on my analyses of socialization in a particular OSS community. In particular, I document the relationships OSS newcomers develop over time with both the social and material aspects of a project. To do so, I combine two mutually informing activities: ethnography and the use of software specially designed to visualize and explore the interacting networks of human and material resources incorporated in the email and code databases of OSS. Socialization in this community is analyzed from two perspectives: as an individual learning process and as a political process. From these analyses it appears that successful participants progressively construct identities as software craftsmen, and that this process is punctuated by specific rites of passage. Successful participants also understand the political nature of software development and progressively enroll a network of human and material allies to support their efforts. I conclude by discussing how these results could inform the design of software to support socialization in OSS projects, as well as practical implications for the future of these projects.     

INTERACTION PATTERNS IN CHILDREN WITH PHENYLKETONURIA.

TO ELUCIDATE THE ROLE OF EMOTIONAL FACTORS IN PHENYLKETONURIA (PKU), 4 S GROUPS COMPRISED OF PKU, RETARDED AND/OR BRAIN DAMAGED, PSYCHOTIC, AND NORMAL CHILDREN WERE COMPARED ON A MEASURE OF INTERACTION BEHAVIOR. ON TOTAL INTERACTION SCORES, THE PKU GROUP WAS FOUND TO PERFORM SIGNIFICANTLY MORE POORLY THAN THE NORMALS, BUT SIGNIFICANTLY BETTER THAN THE PSYCHOTICS. DIFFERENCES BETWEEN THE PKU GROUP AND RETARDED AND/OR BRAIN-DAMAGED GROUP TENDED TOWARD SIGNIFICANCE, ALTHOUGH ON SEPARATE COMPARISONS FOR THE 3 SOCIAL STIMULUS CONDITIONS THE DIFFERENCES BETWEEN THESE 2 GROUPS WERE NOT SIGNIFICANT. THE PKU GROUP WAS FOUND TO BE THE MOST HETEROGENEOUS, AND THE CLUSTERING OF SCORES SUGGESTED THAT PHENYLKETONURIA IS BEHAVIORALLY NOT A UNITARY DISORDER. CORRELATIONS OF INTELLIGENCE CRITERIA AND INTERACTION SCORES FOR THE PKU GROUP FURTHER INDICATED THAT THE INTERACTION MEASURE MAY TAP FUNCTIONS NOT ASSESSED BY STANDARDIZED IQ TESTS. (18 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ISOMETRIC TENSION STUDIES ON CHICKEN PECTORALIS MAJOR MUSCLE

Broiler Pectoralis major developed and released isometric tension in phosphate buffer at varying temperatures and pH levels. The presence of 1 mM calcium or magnesium in the incubation buffer enhanced tension release as did EDTA and combinations of calcium-EDTA or magnesium-EDTA. Tension release rate varied among birds being fastest in those with the shortest time to maximum tension. Amount of tension released 2 hr post-maximum tension correlated significantly (P < 0.01) with amount released from 3 through 12 hr. 2-hr values correlated negatively (P < 0.01) with time to maximum tension but not tenderness (shear value), suggesting that amount of tension release is not indicative of tenderness differences among birds.     

Thermoluminescence Spectra of Inorganic Dust from Irradiated Herbs and Spices

Thermoluminescence (TL) is used to determine whether certain foodstuffs have been irradiated. A high sensitivity TL spectrometer was used to analyze irradiated and unirradiated inorganic dusts from herbs and spices. Unlike earlier TL work using emissions in the UV-green spectral range, the spectrometer monitored transient TL emissions across the spectral range from UV to infra-red as samples were heated to 400°C. A strong high temperature red emission peak was detected in all irradiated samples. This signal was much higher than the background level, insensitive to post-irradiation light exposure, and has potential for irradiation exposure determination.     

影像磨坊 城市历史的多媒体表达

影像磨坊,世界上最大的室外多媒体工程,旨在庆祝魁北克市400周年纪念而设计。这座影像磨坊有个40分钟的视听工程设计以魁北克港口的谷粮仓为背景。这座庞大的混凝土建筑成为了叙述魁北克市400年历史故事的讲说员。     

Abbeystead Outfall Works: Background to Repairs and Modifications – and Lessons Learned

The explosion at the Abbeystead valve house in May 1984, with its attendant loss of life and injury, forcibly drew the attention of the public to the dangers of methane and other natural gases. It also reaffirmed to the water industry and engineering professions the pervasive nature of the gas and the need to take appropriate measures in the construction, design and operation of any scheme which involves a possible methane presence. The investigations into the source and mechanism of the methane gas ingress, and the design of the permanent repairs and modifications to the scheme, have illustrated many of the risks and problems associated with methane and the measures for dealing with them.
The paper describes the essential repairs and modifications which had to be carried out, the main lessons learned, and the recommendations which are felt to be applicable to new and existing water schemes where methane may be present.