Determination of <Emphasis Type="Italic">Bacillus cereus</Emphasis> Emetic Toxin in Food Products by Means of LC–MS²

Cereulide is the heat-stable toxin produced by certain strains of Bacillus cereus. It is the main virulence factor of emetic B. cereus strains, which causes the emetic food poisoning syndrome, including rare fatal cases of food intoxications. Due to presumably low intoxication doses, a sensitive, specific, and robust technique is needed for its detection. In 2002, a LC–MS method was developed which allowed absolute quantification of cereulide using valinomycin as standard. This study describes the validation, according to the Commission Decision 2002/657/EC, of the LC–MS2 method, a tandem mass spectrometry technique, which guarantees lower detection limit and higher specificity. The LC–MS2 method, calibrated with valinomycin, was validated in rice and tested on various matrices (i.e., red beans, spices, and chili con carne) containing cereulide. The process combines a simple extraction step from the food matrix followed by LC–MS2 analysis and detection by ion trap mass spectrometer. The detection limit for cereulide in rice was 0.5 ng eq/g, which is 20 to 2,500 times lower than currently understood intoxicative doses between 10 and 1.280 ng/g previously reported for cereulide. The validated method was specific, sensitive, repeatable, and reproducible with recoveries ranging from 77% to 101%.     

Optimization of hydrolysis of sardine (Sardina pilchardus) heads with Protamex: enhancement of lipid and phospholipid extraction

BACKGROUND: Fish by‐products are not considered as valuable raw materials even if they usually contain valuable components such as lipids. Fish lipids are well known for their nutritional potential and health effects but their extraction remains problematic due to the use of organic solvents. Enzymatic hydrolysis such as the proteolysis of tissues can lead to lipid extraction. RESULTS: Hydrolysis of sardine heads by Protamex was studied (temperature, hydrolysis time and enzyme–substrate ratio) using response surface methodology in order to obtain the highest release of lipids and particularly phospholipids. No relation between the degree of hydrolysis and lipid recovery were depicted; however, optimum conditions for both the release of lipids and phospholipids were found to be similar (29 min, 31 °C with 2.6 g kg^?1 enzyme). Under these hydrolysis conditions, rich lipid and phospholipid fractions (oily and aqueous fractions) can be recovered when time, temperature and enzyme consumption are minimized. Analytical data have revealed that they contain high‐quality lipids, especially ω3 fatty acid. CONCLUSION: This study demonstrated that proteolysis can be used for high lipid recovery from little‐exploited biomass like fish heads without requiring solvent or thermal treatment. Resulting phospholipids, fatty acids and peptides could be utilized for nutritional or feed purposes. Copyright © 2009 Society of Chemical Industry     

Fate of alkylphenolic compounds during activated sludge treatment: impact of loading and organic composition

The impact of loading and organic composition on the fate of alkylphenolic compounds in the activated sludge plant (ASP) has been studied. Three ASP designs comprising carbonaceous, carbonaceous/nitrification, and carbonaceous/nitrification/denitrification treatment were examined to demonstrate the impact of increasing levels of process complexity and to incorporate a spectrum of loading conditions. Based on mass balance, overall biodegradation efficiencies for nonylphenol ethoxylates (NPEOs), short chain carboxylates (NP(1-3)EC) and nonylphenol (NP) were 37%, 59%, and 27% for the carbonaceous, carbonaceous/nitrification, and carbonaceous/nitrification/denitrification ASP, respectively. The presence of a rich community of ammonia oxidizing bacteria does not necessarily facilitate effective alkylphenolic compound degradation. However, a clear correlation between alkylphenolic compound loading and long chain ethoxylate compound biodegradation was determined at the three ASPs, indicating that at higher initial alkylphenolic compound concentrations (or load), greater ethoxylate biotransformation can occur. In addition, the impact of settled sewage organic composition on alkylphenolic compound removal was evaluated. A correlation between the ratio of chemical oxygen demand (COD) to alkylphenolic compound concentration and biomass activity was determined, demonstrating the inhibiting effect of bulk organic matter on alkylphenol polyethoxylate transformation activity. At all three ASPs the biodegradation pathway proposed involves the preferential biodegradation of the amphiphilic ethoxylated compounds, after which the preferential attack of the lipophilic akylphenol moiety occurs. The extent of ethoxylate biodegradation is driven by the initial alkylphenolic compound concentration and the proportion of COD constituted by the alkylphenol polyethoxylates (APEOs) and their metabolites relative to the bulk organic concentration of the sewage composed of proteins, acids, fats, and polysaccharides. Secondary effluents from this study are characterized by low bulk organic concentrations and comparatively high micropollutant concentrations. Based on the biodegradation mechanism proposed in this study, application of high rate tertiary biological treatment processes to secondary effluents characterized by low bulk organic concentrations and comparatively high APEO concentrations is predicted to provide a sustainable solution to micropollutant removal.     

阳台花园

阳台花园位于东京中心一座公寓的第五层。它的设计体现"佗寂"的美学理念,色彩搭配与内部环境相协调。典型的花园背景元素——篱笆在这里成为主角。其由黑竹修成,因为黑竹比绿竹更容易保养,且与城市生活更为协调。用自然纤维制成的黑色绳索把竹子的嫩茎绑到木杠上。为增加篱笆密度,竹子分两层种植,而且下层比上层密集。在竹篱和玻璃门之间的阳台地面铺有木板和白色圆形鹅卵石。鹅     

Correlation between water diffusion and adhesion loss: Study of an epoxy primer on steel

Epoxy adhesion to steel is known to be weakened by the presence of water.     

The value of nonhuman primates in drug abuse research.

The use of nonhuman primates (NHP) is invaluable for drug abuse research. The laboratory animals most closely related to humans are NHP. The phylogeny, anatomy, physiology, neurochemistry, and behavior of NHP are more similar to humans than other laboratory species. There is now an extensive body of literature documenting the neuroanatomical, neurochemical, and neuropharmacological similarities between NHP and humans and the differences between NHP and other laboratory species in dopamine, norepinephrine, serotonin, opioid, and gamma aminobutyric acid systems. Comprehensive studies comparing pharmacokinetics in humans, monkeys, dogs, and rats have shown that data in monkeys are the most predictive of human pharmacokinetic parameters. The long life span and extended adolescent period for NHP permits intensive, long-term investigations and the use of within-subject experimental designs similar to those used in human laboratory studies. Within-subject designs require fewer subjects than standard between-group designs and permit the careful evaluation of individual differences. NHP have been used extensively in drug abuse research for over 40 years and have provided useful information on the behavioral processes associated with drug abuse and addiction as well as drug abuse liability in humans. This review focuses on important species differences between rodents and NHP and on the value of NHP in bridging the gap between rodents and humans to enhance the ability to generalize preclinical findings to human drug abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The aftermath of 9/11: Effect of intensity and recency of trauma on outcome.

Does trauma exposure have a long-term impact on the brain and behavior of healthy individuals? The authors used functional magnetic resonance imaging to assess the impact of proximity to the disaster of September 11, 2001, on amygdala function in 22 healthy adults. More than three years after the terrorist attacks, bilateral amygdala activity in response to viewing fearful faces compared to calm ones was higher in people who were within 1.5 miles of the World Trade Center on 9/11, relative to those who were living more than 200 miles away (all were living in the New York metropolitan area at time of scan). This activity mediated the relationship between group status and current symptoms of posttraumatic stress disorder. In turn, the effect of group status on both amygdala activation (fearful vs. calm faces) and current symptoms was statistically explained by time since worst trauma in lifetime and intensity of worst trauma, as indicated by reported symptoms at time of the trauma. These data are consistent with a model of heightened amygdala reactivity following high-intensity trauma exposure, with relatively slow recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developing the competitive organization: Interventions and strategies.

The competitive environment is giving rise to a paradigmatic transformation in how corporations organize and manage people. These transformations typically start with new outlying organizational units and progress slowly as innovations in management diffuse to older, more resistant organizations. Changes in these older units require the involvement of all stakeholders in designing an organization that will demand new behavior of them. Attitudes and new skills are developed through experience with new approaches to management, not education. Effective and rapid corporate transformation requires top management to develop a corporate context that will support diffusion. Champions who will lead change must be carefully placed to move change along, and they can benefit from the support of consultants skilled in both process and structural interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Algorithm 32 automatic computation of integrals with singular integrand,over a finite or an infinite range

A numerical quadrature algorithm is developed, for integrands which may exhibit some kind of singular behaviour within the finite of infinite integration range. Using the automatical FORTRAN IV integration program, one should provide the abscissae the function is not “smooth” at. The quadrature formula has been obtained by applying the trapezoidal rule after transformation of the integrand. Standing severe tests which were based on the test functions of Casaletto et al. and on Kahaner's sample set, the integration scheme turned out to be of a remarkable reliability, efficiency and accuracy.     

Shadows of the Past in International Cooperation: Collaboration Profiles of the Top Five Producers of Science

This article aims at a characterization of the cooperation behavior among five large scientific countries (France, Germany, Japan, United Kingdom and United States of America) from 1986 to 1996. It looks at the cooperation profiles of these countries using classical measures such as the Probabilistic Affinity. The results show the major influence which historical, cultural and linguistic proximities may have on patterns of cooperation, with few changes over the period of time studied.A lack of specific affinities among the three largest European countries is revealed, and this contrasts with the strong linkage demonstrated between United States and Japan. The ensuing discussion raises some questions as to the process of Europeanization in science. The intensity of bilateral cooperation linkages is then studied with regard to field specialization by country, and this analysis yields no general patterns at the scale studied. Specific bilateral behaviors are also analyzed.