Modulation of hepatic and intestinal glutathione S-transferases and other antioxidant enzymes by dietary lipids in streptozotocin diabetic rats

Antioxidant enzymes in liver and small intestine were investigated using control and streptozotocin diabetic rats fed diets with 5% olive, sunflower or fish oil for five weeks. In liver, Glutathione Peroxidase and Superoxide Dismutase decreased and in intestine Glutathione-S-transferase (GST) increased by diabetes. In isolated jejunum and ileum, this increase in GST activity was due to an increase in GST-alpha and -mu isoenzymes in jejunum and GST-alpha, mu and -pi in ileum. Since GST plays an important role in protecting tissues from oxidative damage, our results highlight the role of the intestine against free radicals in physiological or pathological situations.     

Effects of ozone on yield, growth, and root starch concentrations of two alfalfa (Medicago sativ A L.) cultivars

Ozone (O3) is considered to be a major air pollutant that affects the yield of several sensitive crop species. Its concentration may reach phytotoxic levels several times during the growing season in Eastern Canada. This study was initiated to evaluate the O3 effects on alfalfa, a major crop species. The objective was to compare the yield and growth parameters of the main alfalfa cultivar used in Québec, Apica, to a cultivar more tolerant to O3, Team. Effects on root starch concentrations were also examined as this parameter is an important indicator of alfalfa perennity. The results obtained have shown that the forage yield of Apica was more reduced by O3 during two growing seasons than the yield of Team. For O3 concentrations of 20 to 40 nl liter(-1), yield reductions were 14-26% for Apica and 0-20% for Team. Whereas Apica could be considered more susceptible to O3 than Team, the latter has shown contrasting responses from year to year. This fact suggests that the mechanisms involved in O3-tolerance could be modulated by environmental conditions. At low O3 levels, Apica has shown reduced root growth in terms of dry matter and length. However, contrary to the current hypothesis that O3 would affect more root than shoot growth, we were unable to show a consistent alteration of the biomass allocation between the two. Ozone seems to reduce globally the growth of the whole plants. The greater O3-tolerance of Team could partly be associated to its capacity to maintain more leaves, to delay their senescence, or to keep a larger leaf:stem ratio under increasing levels of O3. At the end of the two growing seasons, the amount of starch reserves stored below ground was shown to be reduced by the current O3 levels. This reduction was mainly associated with a decrease in root biomass under O3 stress. This result support the hypothesis that O3 may accelerate alfalfa decline under field conditions.     

城市二级污水灌溉对几种园林植物生长的影响

以新疆乌鲁木齐市东郊七道弯污水处理厂二级出水为研究对象．开展了二级污水对几种园林植物(万寿菊、紫穗槐、高羊茅、早熟禾)生理、生态的影响研究。与对照组相比，结果表明，草坪草、紫穗槐叶绿素含量、净光合速率、地上部分生物量增加。     

Changes in the levels of aspartate and alanine aminotransferase activities of Anabastestudineus (Bloch) exposed to disyston

In $\text{Anabas}$$\text{testudineus}$, the per cent changes noted in the aspartate aminotransferase (AAT) activities of gill, brain, intestine, liver, muscle and kidney until 6 hr of exposure to lethal concentration (10.5 mg/L disyston) were relatively much less when compared to those of sublethal concentration (4.0 mg/L disyston). But in the case of alanine aminotransferase (AIAT) activity, the tissues which showed such effect (paradoxical effect) were gill, brain and liver.     

First Detection of Hepatitis E Virus in Shellfish and in Seawater from Production Areas in Southern Italy

Shellfish samples (n = 384) from production areas, water samples from the same areas (n = 39) and from nearby sewage discharge points (n = 29) were analyzed for hepatitis E virus (HEV) by real-time and nested RT-PCR. Ten shellfish samples (2.6%) and five seawater samples (12.8%) tested positive for HEV; all characterized strains were G3 and showed high degree of sequence identity. An integrated surveillance in seafood and waters is relevant to reduce the risk of shellfish-associated illnesses.     

Nanomaterials for environmental burden reduction, waste treatment, and nonpoint source pollution control: a review

Nanomaterials are applicable in the areas of reduction of environmental burden, reduction/treatment of industrial and agricultural wastes, and nonpoint source (NPS) pollution control. First, environmental burden reduction involves green process and engineering, emissions control, desulfurization/denitrification of nonrenewable energy sources, and improvement of agriculture and food systems. Second, reduction/treatment of industrial and agricultural wastes involves converting wastes into products, groundwater remediation, adsorption, delaying photocatalysis, and nanomembranes. Third, NPS pollution control involves controlling water pollution. Nanomaterials alter physical properties on a nanoscale due to their high specific surface area to volume ratio. They are used as catalysts, adsorbents, membranes, and additives to increase activity and capability due to their high specific surface areas and nano-sized effects. Thus, nanomaterials are more effective at treating environmental wastes because they reduce the amount of material needed.     

广州市生活饮用水地表水源地微量元素调查

对广州市秀全、巴江、江村、石门、西村、刘屋洲、南洲和沙湾等主要生活饮用水地表水源地中钼、钴、铍、硼、锑、镍、钒、钛、锡、银和钡等微量元素含量水平进行了调查,并采用单因子污染指数法和内梅罗综合污染指数法对微量元素水质进行了评价。结果表明,硼和锡在所有地表水源地均未检出,铍在部分地表水源地有检出,其他检测项目在所有地表水源地均有检出。整体而言,微量元素含量水平不高,地表水源地由北往南微量元素内梅罗指数呈逐渐降低态势,南部水源地水质优于北部水源地。巴江和西部水源地镍含量相对较高,电镀企业排污监管力度有待进一步加强。     

Fire ant venom alkaloids act as key attractants for the parasitic phorid fly, Pseudacteon tricuspis (Diptera: Phoridae)

The phorid fly, Pseudacteon tricuspis Borgmeier, is an introduced parasitoid of imported fire ants, Solenopsis spp., in the USA. Although the assumption that phorid flies use fire ant alarm pheromones for host location is probably true, we demonstrated in a previous study the possible involvement of other ant semiochemicals in the response of P. tricuspis to fire ants. This study was conducted to determine the glandular sources and identity of the semiochemicals mediating this interaction. First, we tested the electroantennogram response of P. tricuspis to extracts of key body parts and glands of workers of the red imported fire ant, S. invicta Buren. The results confirm that the poison (venom) gland/sac is the key source of compounds which elicited strong antennal activity in P. tricuspis. Follow-up studies were conducted by using a combination of bioassay-guided fractionation and behavioral bioassays to test the hypothesis that attraction of this parasitoid to fire ants is mediated by venom alkaloids. The results confirm the response of P. tricuspis to physiologically relevant amounts of the two venom alkaloid fractions (cis and trans alkaloid fractions) of S. invicta. Further analysis by coupled gas chromatography–electroantennogram detection revealed nine venom alkaloid components including two novel 2,6-dialkylpiperideines that elicited significant antennal activity in P. tricuspis. This is the first demonstration of the role of venom alkaloids of ants as attractants for their natural enemies. We propose a semiochemical-mediated host location mechanism for P. tricuspis involving both alarm pheromones and venom alkaloids. The ecological significance of these findings, including the attraction of male P. tricuspis to fire ant venom alkaloids, possibly for mate location, is discussed.     

Error Assessment for Height Above the Nearest Drainage Inundation Mapping

Real‐time flood inundation mapping is vital for emergency response to help protect life and property. Inundation mapping transforms rainfall forecasts into meaningful spatial information that can be utilized before, during, and after disasters. While inundation mapping has traditionally been conducted on a local scale, automated algorithms using topography data can be utilized to efficiently produce flood maps across the continental scale. The Height Above the Nearest Drainage method can be used in conjunction with synthetic rating curves (SRCs) to produce inundation maps, but the performance of these inundation maps needs to be assessed. Here we assess the accuracy of the SRCs and calculate statistics for comparing the SRCs to rating curves obtained from hydrodynamic models calibrated against observed stage heights. We find SRCs are accurate enough for large‐scale approximate inundation mapping while not as accurate when assessing individual reaches or cross sections. We investigate the effect of terrain and channel characteristics and observe reach length and slope predict divergence between the two types of rating curves, and SRCs perform poorly for short reaches with extreme slope values. We propose an approach to recalculate the slope in Manning’s equation as the weighted average over a minimum distance and assess accuracy for a range of moving window lengths.     

Motorcycle safety among motorcycle taxi drivers and nonoccupational motorcyclists in developing countries: A case study of Maoming,South China

Objective: An increasing number of motorcycle taxis have been involved in traffic crashes in many developing countries. This study examines the characteristics of both motorcycle taxi drivers and nonoccupational motorcyclists, investigates the risks they pose to road safety, and provides recommendations to minimize their risks.

Methods: Based on the data collected from a questionnaire survey of 867 motorcycle taxi drivers and 2,029 nonoccupational motorcyclists in Maoming, South China, comparisons were made to analyze differences of personal attributes, attitudes toward road safety, and self-reported behavior of the 2 groups.

Results: Results of the chi-square tests show that not only motorcycle taxi drivers but also nonoccupational motorcyclists in Maoming held poor attitudes toward road safety and both groups reported unsafe driving behavior. There is much room for improving local road safety education among all motorcyclists in Maoming. Yet, motorcycle taxi drivers were more likely to pose road safety risks than nonoccupational motorcyclists under some circumstances, such as speeding late at night or early in the morning, not requiring passengers to wear helmets, and running a red light. The results of the binary logistic regression model show that possessing a vehicle license for a motorcycle or not was the common significant predictor for unsafe driving behavior of motorcycle taxi drivers and nonoccupational motorcyclists. Therefore, enforcement against all motorcyclists not showing vehicle licenses for their motorcycles should be stepped up.

Conclusion: Motorcycle safety is largely poor in Maoming. Therefore, efforts to improve motorcycle safety should be strengthened by targeting not only motorcycle taxi drivers but also nonoccupational motorcyclists.