Egg Thiamine Status of Lake Ontario Salmonines 1995–2004 with Emphasis on Lake Trout

Alewives (Alosa pseudoharengus), the major prey fish for Lake Ontario, contain thiaminase. They are associated with development of a thiamine deficiency in salmonines which greatly increases the potential for developing an early mortality syndrome (EMS). To assess the possible effects of thiamine deficiency on salmonine reproduction we measured egg thiamine concentrations for five species of Lake Ontario salmonines. From this we estimated the proportion of families susceptible to EMS based on whether they were below the ED20, the egg thiamine concentration associated with 20% mortality due to EMS. The ED20s were 1.52, 2.63, and 2.99 nmol/g egg for Chinook salmon (Oncorhynchus tshawytscha), lake trout (Salvelinus namaycush), and coho salmon (Oncorhynchus kisutch), respectively. Based on the proportion of fish having egg thiamine concentrations falling below the ED20, the risk of developing EMS in Lake Ontario was highest for lake trout, followed by coho (O. kisutch), and Chinook salmon, with the least risk for rainbow trout (O. mykiss). For lake trout from western Lake Ontario, mean egg thiamine concentration showed significant annual variability during 1994 to 2003, when the proportion of lake trout at risk of developing EMS based on ED20 ranged between 77 and 100%. Variation in the annual mean egg thiamine concentration for western Lake Ontario lake trout was positively related (p < 0.001, r² = 0.94) with indices of annual adult alewife biomass. While suggesting the possible involvement of density-dependent changes in alewives, the changes are small relative to egg thiamine concentrations when alewife are not part of the diet and are of insufficient magnitude to allow for natural reproduction by lake trout.     

An integrated energy planning model for Illinois

An integrated energy supply and demand model for the state of Illinois is described. This equilibrium model is an important tool for integrating information from a variety of planning studies and data bases. A wide range of energy issues affecting diverse areas of the energy system, such as Illinois coal production under alternate oil price assumptions, renewable energy resource potential, and conservation options, can be analyzed by using the model.     

Occurrence of Lawn Care and Agricultural Pesticides in the Don River and Humber River Watersheds (1998–2002)

Between 1998 and 2002, surface water samples were collected from several sites in the Don River and Humber River watersheds, both tributaries to Lake Ontario, and analyzed for a variety of pesticides, including those used for urban lawn care. Analyses included 152 pesticide active ingredients and eight metabolites. Samples were collected during base flow periods (i.e., dry events) and rainfall events (i.e., wet events). The objectives of the study were to determine which pesticides were detectable, whether there was a difference in the detection frequency between the two watersheds and between upstream and downstream in each river, and whether precipitation influenced the frequency of detection. Eleven pesticides and one metabolite were detected in surface waters of the Don and Humber rivers or their tributaries, with approximately 72% of samples containing at least one pesticide attributable to lawn care use. The pesticides and pesticide metabolite detected in this study included 2,4-D, atrazine, bromacil, carbofuran, chlorpyrifos, cypermethrin, diazinon, dicamba, MECOPROP, metolachlor, metribuzin, and an atrazine metabolite (des-ethyl atrazine). Four pesticides exceeded federal or provincial water quality guidelines/objectives. Diazinon exceeded the provincial water quality objective in 28% of the samples taken. For the three other pesticides (atrazine, carbofuran and chlorpyrifos) exceedance of a water quality criteria occurred in less than 1% of the samples.     

Spatio-Temporal Short-Term Urban Traffic Volume Forecasting Using Genetically Optimized Modular Networks

Abstract:   Current interest in short-term traffic volume forecasting focuses on incorporating temporal and spatial volume characteristics in the forecasting process. This article addresses the problem of integrating and optimizing predictive information from multiple locations of an urban signalized arterial and proposes a modular neural predictor consisting of temporal genetically optimized structures of multilayer perceptrons (MLP) that are fed with volume data from sequential locations to improve the accuracy of short-term forecasts. The results show that the proposed methodology provides more accurate forecasts compared to the conventional statistical methodologies applied, as well as to the static forms of neural networks.     

Cytokine responses of human lung cells (BEAS-2B) treated with micron-sized and nanoparticles of metal oxides compared to soil dusts

Background  

The induction of cytokines by airway cells in vitro has been widely used to assess the effects of ambient and occupational particles. This study measured cytotoxicity and the release of the proinflammatory cytokines IL-6 and IL-8 by human bronchial epithelial cells treated with manufactured nano- and micron-sized particles of Al₂O₃, CeO₂, Fe₂O₃, NiO, SiO₂, and TiO₂, with soil-derived particles from fugitive dust sources, and with the positive controls LPS, TNF-α, and VOSO₄.     

Evaluation of a system of wind tunnels for field studies of ammonia loss from grassland through volatilisation

Rates of ammonia (NH₃) loss from a ryegrass sward measured using a system of small wind tunnels were compared with concurrent measurements made using a micrometeorological mass balance method. Measurements were made during two experiments within a circular plot (radius 10m) treated with urea at a rate of 200kgNha^?1. In the first experiment, air speed through the tunnels was adjusted as necessary to maintain a value of approximately 1ms^?1. This value differed on most occasions from the mean ambient wind speed which was measured at a height of 250mm and which ranged from 0.61 to 2.95ms^?1. Rates of loss measured using the wind tunnels differed by a factor of between two and five from those measured using the mass balance method; there was no consistent pattern in the differences between the rates of loss. The total losses of NH₃ measured during 15 days were equivalent to 49.1 and 30.2kg Nha^?1 for the mass balance and wind tunnel methods, respectively. In the second experiment, air speed through the tunnels was adjusted as necessary to maintain a value as close as possible to the mean ambient wind speed measured at a height of 250mm. Rates of NH₃ loss measured using the two methods did not differ significantly; total losses of NH₃ during 17 days were equivalent to 96.9 and 101kg Nha^?1 for the mass balance and wind tunnel methods, respectively. The difference between the findings of the two experiments could be attributed to the direct effect of air speed through the tunnels rather than to differences between ambient temperatures and those inside the tunnels. During and following periods of rain the rates of loss measured using the tunnels were up to six times greater than those observed with the mass balance method. Rates of loss measured by the two methods became similar again when the tunnels were moved following rain. The study demonstrates that enclosures can be designed and operated to provide reliable measurements of the rate of NH₃ loss from grassland. Potential applications of the two methods are discussed.     

An LP-based heuristic procedure for the generalized assignment problem with special ordered sets

The generalized assignment problem with special ordered sets (GAPS2), is the problem of allocating n tasks to m time-periods, where each task must be assigned to a time-period, or shared between two consecutive time-periods. For reasonably large values of m and n the NP-hard combinatorial problem GAPS2 becomes intractable for standard mathematical programming software, hence there is a need for heuristic algorithms to solve such problems. It will be shown how an LP-based heuristic developed previously for the well-established generalized assignment problem can be modified and extended to solve GAPS2. Encouraging results, in terms of speed and accuracy, in particular when compared to an existing heuristic for GAPS2, are described.     

An improved enzymic method for the determination of native and modified starch

An improved method for the determination of starch by sequential hydrolysis with thermostable bacterial α-amylase and fungal amyloglucosidase is described. Glucose was determined colorimetrically by a glucose oxidase-peroxidase-chromogen system at pH 7. Native normal and waxy starches, and distarch phosphate, gave quantitative yields of glucose with a high degree of precision (coefficient of variation less than 1%). Acetylated distarch phosphate, high-amylose starch and retrograded amylose were initially treated with 1M NaOH for 30 min, then neutralised and analysed successfully as normal starch. Oxidised starch did not give a quantitative yield of glucose because of the presence of dicarboxylic groups in the polymer. For samples containing normal and waxy starch the analysis was carried out in about 4 h. The method was applied to a range of starch-containing foodstuffs and the results are reported.     

Some nitrosoamino acids in bacon adipose tissue and their contribution to the total N-nitroso compound concentration

Zusammenfassung Der Gehalt an Nitrosoaminosäuren und ihr Anteil an den Gesamt-N-Nitrosoverbindungen im Fettgewebe von rohem Schinkenspeck wurde untersucht. In 80% der Proben wurde ein Gehalt an Nitrosoaminosäuren von bis zu 0,2 mg/kg festgestellt. Scheinbare Gesamt-N-Nitrosoverbindungen waren in allen Proben in einer Konzentration von 0,4 bis 3,7 mg (N-NO)/kg vorhanden. Die eigentlichen Nitrosoaminosäuren machen nur etwa 1% der scheinbaren Gesamt-N-Nitrosoverbindungen aus. Die Mehrzahl der scheinbaren Gesamt-N-Nitrosoverbindungen im Fettgewebe findet sich im nichtlöslichen Bindegewebe, wobei der verbleibende Rest chloroformlöslich ist.Summary The levels of nitrosoamino acids and apparent total N-nitroso compounds in the adipose tissue of raw bacon have been examined. Nitrosoamino acids were detected in 80% of the samples in levels of up to 0.2 mg/kg. Apparent total N-nitroso compounds were present in all samples in concentrations of between 0.4 and 3.7 mg (N-NO)/kg. Nitrosoamino acids accounted for approximately only 1 % of the apparent total N-nitroso compounds. The majority of the apparent total N-nitroso compounds in the adipose tissue were associated with the insoluble connective tissue fraction, with the remainder present as chloroform soluble species.

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Einige Nitrosoaminosäuren im fettgewebe von Schinkenspeck und ihr anteil an der Konzentration der Gesamt-N-Nitrosoverbindungen

     

Type A behavior, aerobic power, and cardiovascular recovery from a psychosocial stressor.

Investigated the relationship between Type A (coronary prone) behavior, aerobic fitness, and cardiovascular recovery from stress in 56 male undergraduates. Ss were tested for actual aerobic power and Type A behavior on the Jenkins Activity Survey—Form T before performing the Stroop Color–Word Interference Test. Type A behavior was related to speed of recovery following the test, with Type As being slower to return to baseline heart rate levels than Type B (noncoronary prone) Ss. Physiological and cognitive variables affecting speed of recovery from stress are examined, and the lack of effect of fitness on recovery is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)