Effects of seasonal variation in precipitation on estimation of non-point source pollution.

The extent of nonpoint source pollution (NPSP) generated from upstream catchment areas of a reservoir is normally estimated based on a design rainfall. However, rainfall generally varies in different seasons. This seasonal change may significantly influence the estimation of runoff volume and associated NPSP arising within a reservoir watershed. The NPSP management, reservoir operation, and water treatment operation strategies developed based on the estimation will also be altered. This study analyzes the effects of monthly and seasonal variation in precipitation on the estimation of pollution levels from nonpoint sources in a reservoir watershed. The area studied is the Derchi reservoir watershed located in central Taiwan. This watershed is subdivided into twenty-six sub-watersheds, and the Thiessen method is used to determine the rainfall intensity in each sub-watershed. Runoff pattern and NPSP contributions for each sub-watershed are estimated using the AGNPS model. Results show significant seasonal variation in precipitation; estimated NPSP loads likewise vary significantly over time. Seven- to one hundred-fold differences among monthly and seasonal estimations of phosphorus and sediment loads are observed.

A multiobjective model for non-point source pollution control for an off-stream reservoir catchment.

Phosphorus loads from agricultural non-point source pollution (NPSP) significantly degrade reservoir water quality, making adequate control of agricultural NPSP necessary for improving the water quality. Controlling NPSP is generally accomplished using various Best Management Practices (BMPs). The present study applies the Agricultural Non-Point Source Pollution (AGNPS) model to simulate NPSP loading and BMP efficiencies and establishes an enhanced multiobjective mixed-integer programming model for NPSP control strategy analyses based on these results. Cost, phosphorus load, sediment load and equity are the four major objectives considered. A case study for the Posan reservoir is presented. Four commonly proposed and applicable BMPs are chosen. Non-inferior solutions obtained using the constraint method and trade-off relationships among different control objectives are described and discussed. Compared with a previously proposed fertilizer control model, results show that the model established herein is more cost-effective and achieves better phosphorus and sediment loading reduction and equity goals. Furthermore, the current model is expected to facilitate decision-making analysis for development of an appropriate cost-sharing program to encourage adoption of appropriate BMPs by farmers.

Forecasts using neural network versus Box-Jenkins methodology for ambient air quality monitoring data.

This study explores ambient air quality forecasts using the conventional time-series approach and a neural network. Sulfur dioxide and ozone monitoring data collected from two background stations and an industrial station are used. Various learning methods and varied numbers of hidden layer processing units of the neural network model are tested. Results obtained from the time-series and neural network models are discussed and compared on the basis of their performance for 1-step-ahead and 24-step-ahead forecasts. Although both models perform well for 1-step-ahead prediction, some neural network results reveal a slightly better forecast without manually adjusting model parameters, according to the results. For a 24-step-ahead forecast, most neural network results are as good as or superior to those of the time-series model. With the advantages of self-learning, self-adaptation, and parallel processing, the neural network approach is a promising technique for developing an automated short-term ambient air quality forecast system.

Ibuprofen: new explanation for an old phenomenon.

Nuclear factor-kappaB (NF-kappaB) translocation from the cytoplasm into the nucleus and the subsequent DNA binding is an essential prerequisite in the up-regulation of many pro-inflammatory genes, e.g. tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta). The anti-inflammatory drug ibuprofen, thought to exert its beneficial effects mainly by suppressing the production of eicosanoids, inhibited the up-regulation of the pro-inflammatory cytokines IL-1beta and TNF-alpha. This effect was independent of the described potential of ibuprofen as a cyclooxygenase inhibitor. Ibuprofen inhibited the activation and translocation of the key transcription factor NF-kappaB by blocking the degradation of inhibitor-kappaBalpha, a protein that forms a complex with NF-kappaB, thereby preventing the release and subsequent translocation of NF-kappaB into the nucleus and the expression of inflammatory cytokines. The presented data offer a new explanation for the anti-inflammatory effect of ibuprofen.

Arachidonic acid influences proinflammatory gene induction by stabilizing the inhibitor-kappaBalpha/nuclear factor-kappaB (NF-kappaB) complex, thus suppressing the nuclear translocation of NF-kappaB.

Arachidonic acid (AA), through its myriad metabolites, is involved in inflammation in a number of ways. AA is produced and released by several cell types, including endothelial cells (EC), and acts on a variety of cells. EC activation plays a key role in inflammation presumably by modulating the immune response through up- or down-regulation of several genes. We have previously shown that AA and its nonmetabolizable analogue, 5,8,11,14-eicosatetraynoic acid (ETYA), inhibit up-regulation of proinflammatory genes in EC. In the present study we identify a mechanism to explain the inhibitory effects: AA and ETYA both inhibit the translocation of nuclear factor-kappaB (NF-kappaB) to the nucleus by blocking the degradation of the inhibitor of NF-kappaB (IkappaB) and thus stabilizing the IkappaB/NF-kappaB complex. To investigate the mechanism whereby AA inhibits up-regulation of genes encoding proinflammatory mediators, we examined the ability of ETYA to inhibit tumor necrosis factor-alpha (TNF-alpha) mediated phosphorylation and degradation of IkappaBalpha. Western blot analysis revealed that preincubation of EC with ETYA for 40 min prior to stimulation with TNF-alpha inhibits the phosphorylation and degradation of IkappaBalpha. These findings establish a mechanism by which AA inhibits nuclear translocation of NF-kappaB and thereby explaining its modulatory role in the induction of proinflammatory genes.

Characterization of glycoconjugates in the bovine endometrium and chorion by lectin histochemistry.

Lectin binding patterns were examined on normal bovine endometrium and bovine placentomes during four stages of pregnancy using 13 biotinylated lectins. Lectin binding intensity increased in early pregnancy for many lectins, whereas binding to fucosyl residues decreased. Persistence of strong lectin binding later in pregnancy usually was limited to the arcade and intercotyledonary trophoblastic cells. Binding of some lectins to cell surfaces was prominent, particularly in early pregnancy. A few lectins were excellent markers for binucleate trophoblastic cells. These distinctive surface and binucleate cell binding patterns on placentomes and endometrial epithelium are useful markers of trophoblastic cell-endometrial epithelial cell surface interactions and of binucleate cell differentiation.

Chinese alchemy: confluence and transformation.

The study of China's alchemical tradition can provide considerable insight into early Chinese medical theory, pharmaco-therapeutic practice and psychosomatic concepts. Chinese alchemy is a complex blending of philosophical, cosmological, physiological and natural scientific thought. This article presents a historical survey and analysis of some important aspects of Chinese alchemical research and theory.

The cardiovascular effects of lithium in man. A review of the literature.

The medical literature since 1900 has been reviewed to determine the nature of lithium's cardiovascular effects. In therapeutic doses, lithium produces reversible T wave flattening and inversion in the electrocardiogram: rarely, it may cause sinus node dysfunction or ventricular arrhythmias. Patients with lithium toxicity almost always present with neurologic signs and symptoms. "Hypotension and cardiovascular collapse," alleged cardiotoxic manifestations of lithium, invariably follow days of coma. Given the possible cardiotoxic effect other psychopharmacologic agents and the hazards of withholding effective therapy in mania, it is concluded that lithium may be used safely in patients with cardiac disease if the dose is adjusted to the rate of lithium excretion and if serum levels of lithium are followed carefully. When used in patients with cardiac arrhythmias, frequent electrocardiographic monitoring is advised.