不同碳源条件下草菇内切型纤维素酶基因（eg1）转录表达的分析

利用Northernblot方法分析了不同碳源条件下草菇切型纤维素酶基因(eg1)的表达.结果发现,在含有纤维素的液体培养基中生长10d,eg1在草菇菌丝中有高效表达;纤维二糖、α-乳糖、β-乳糖,也能诱导eg1的表达,但和纤维素相比,eg1的表达量相对较低,并且它们的诱导效应在加入这类糖12h后迅速减弱;槐糖和龙胆二糖的诱导作用非常弱.在天然稻草为基质的固体栽培料生长时,草菇eg1的表达和草菇菌丝生长与出菇相对应,在菌丝生长期(d8)可见eg1的表达,d12时菌丝已长满,表达减弱,在出菇及菇体的分化及增大期,eg1的表达量逐渐增强,在成熟期达到最高水平;表明在草菇菇体发育中需要更多碳源及能源的补充,eg1在这方面起着非常重要的作用.图4参14     

Diet shifts during egg laying: Implications for measuring contaminants in bird eggs

We combined stable isotope tracers of blood plasma, blood cells and egg contents with faecal analysis during pre-breeding and egg laying phases in two dipper species Cinclus cinclus and Cinclus mexicanus to determine the occurrence of dietary shifts during egg production and to assess consequences for egg contaminant loads. In both species, changes in δ¹³C (C. cinclus) or δ¹⁵N (C. mexicanus) in female plasma relative to red blood cells indicated a dietary shift during laying that was not observed in males. Eurasian dippers increased prey consumption as breeding approached, shifting from primarily trichopteran insect larvae to ephemeropterans and plecopterans. In American dippers, egg-laying females switched to feeding at a higher trophic level by consuming more fish. Eggs derived from higher trophic level diets contained more mercury (American dipper), polychlorinated biphenyls and some organochlorines, especially DDT metabolites. The results demonstrate how dietary changes during egg laying accompany the demands for egg production with consequences for contaminant deposition in avian eggs.     

Enantiomer fractions of polychlorinated biphenyls in three selected Standard Reference Materials

The enantiomer composition of six chiral polychlorinated biphenyls (PCBs) were measured in three different certified Standard Reference Materials (SRMs) from the US National Institute of Standards and Technology (NIST): SRM 1946 (Lake Superior fish tissue), SRM 1939a (PCB Congeners in Hudson River Sediment), and SRM 2978 (organic contaminants in mussel tissue--Raritan Bay, New Jersey) to aid in quality assurance/quality control methodologies in the study of chiral pollutants in sediments and biota. Enantiomer fractions (EFs) of PCBs 91, 95, 136, 149, 174, and 183 were measured using a suite of chiral columns by gas chromatography/mass spectrometry. Concentrations of target analytes were in agreement with certified values. Target analyte EFs in reference materials were measured precisely (<2% relative standard deviation), indicating the utility of SRM in quality assurance/control methodologies for analyses of chiral compounds in environmental samples. Measured EFs were also in agreement with previously published analyses of similar samples, indicating that similar enantioselective processes were taking place in these environmental matrices.     

Waste management models and their application to sustainable waste management

The purpose of this paper is to review the types of models that are currently being used in the area of municipal waste management and to highlight some major shortcomings of these models. Most of the municipal waste models identified in the literature are decision support models and for the purposes of this research, are divided into three categories-those based on cost benefit analysis, those based on life cycle assessment and those based on multicriteria decision making. Shortcomings of current waste management models include that they are concerned with refinements of the evaluation steps (e.g. stage four of AHP or the improvement of weight allocations in ELECTRE) rather than addressing the decision making process itself. In addition, while many models recognise that for a waste management model to be sustainable, it must consider environmental, economic and social aspects, no model examined considered all three aspects together in the application of the model.     

Biodegradable municipal waste (BMW) management strategy in Ireland: A comparison with some key issues in the BMW strategy being adopted in England

Due to increasing pressure from the European Union to meet recycling and recovery targets, (e.g. the packaging waste, waste electronic equipment and landfill directives), both the Irish and England's governments’ policy on waste management is changing to meet these pressures, with major emphasis upon the management of biodegradable municipal waste (BMW). In particular, the EU landfill directive requires reductions in the rate of biodegradable waste going to landfill to 35% by 2016. The objective of this paper is to examine how Ireland plans to meet this challenge and to compare the Irish strategy to that being adopted in England. The approach in England is driven by a clear understanding that the practice in the late 1990s was unlikely to ensure compliance with EU targets by the set dates. England has therefore developed a discrete, programme (Waste Implementation Programme) to drive a new approach, based on rigorous science and international best practice, which includes a Demonstrator Programme for new technologies. The dynamic, high cost, large scale programme in England stands in sharp contrast to that for Ireland and only future, detailed analysis of outcomes will be able to evaluate the cost effectiveness of each.     

Satellite telemetry and prey sampling reveal contaminant sources to Pacific Northwest Ospreys.

Migratory behavior can be an important factor in determining contaminant exposure in avian populations. Accumulation of organochlorine (OC) pesticides while birds are wintering in tropical regions has been cited often as the reason for high concentrations in migrant populations. To explore this issue, we satellite tracked 16 Ospreys (Pandion haliaetus) over the period 1996-2003 from breeding sites in British Columbia, Canada, and integrated the results into a database on 15 Ospreys that were satellite tracked over the period 1995-1999, from breeding locations in Washington and Oregon, USA. Data on wintering sites of 31 Ospreys in Mexico and Central America were used for spatially targeted sampling of prey fish. Concentrations of the main organochlorine contaminant, p,p'-dichloro-diphenyl-dichloroethylene (DDE), in fish composites from Mexico ranged from 0.005 to 0.115 nicrog/g wet mass. Significant differences existed among fish families in p,p'-DDE, total dichloro-diphenyl-trichloroethane (sigmaDDT), sigmachlordanes, and total polychlorinated biphenyls (sigmaPCBs). Catfish (family Ariidae) generally had significantly higher levels of DDT metabolites and other organochlorine contaminants compared to other fish families collected. Differences in prey contaminant levels were detected among the collection sites around coastal Mexico, with fish from Veracruz State generally having higher levels of DDT metabolites, sigmachlordanes, sigmaPCBs, and hexachlorobenzene. Eggs collected from 16 nests throughout the Pacific Northwest (nine from British Columbia, seven from Oregon and Washington) where Ospreys had been satellite tagged, showed marked variation in levels of DDT metabolites (p,p'-DDE; range 0.02-10.14 microg/g). Wintering site had no significant effect on contaminant concentrations in sample eggs from those specific Ospreys; rather concentrations of p,p'-DDE, were predicted by breeding sites with highest levels in eggs of Ospreys breeding in the lower Columbia River, consistent with published reports of continued high concentrations of DDT and related compounds in that system.     

Influence of size on primary production in the reef coral Pocillopora damicornis and the macroalga Acanthophora spicifera

Size influences the photosynthesis-irradiance (P-I) relationship in colonies of the branched reef-coral Pocillopora damicornis and in intact plants of the branched redmacroalga Acanthophora spicifera. The light saturation constant is proportional to size. Maximum net rate of oxygen production (net photosynthesis) per colony and nocturnal dark oxygen-uptake rate per colony (respiration) increase with increasing size, but the latter increases at a much lower rate. Therefore, the photosynthesis to respiration ratio increases with increasing canopy size. Large increases in chlorophyll per unit reef area also accompany increase in size. The initial slope (alpha) of the chlorophyll-specific P-I curve and assimilation number are inversely related to size. Integrated daytime oxygen production increases with size more rapidly than nighttime oxygen consumption. Consequently, net primary production of an entire colony or plant (or rate per unit area of reef) increases with increasing size of the canopy. Production efficiency also increases with size. The coral is rigid, symmetrical and highly organized. Chlorophyll distribution is more stratified in comparison to the macroalga. The coral shows higher photosynthetic efficiency, as would be expected according to the stratified production model of Odum et al. (1958). This research was conducted on specimens from Kaneohe Bay, Oahu, Hawaii, USA in 1981.     

Pesticide treatments affect mountain pine beetle abundance and woodpecker foraging behavior.

In British Columbia, Canada, management efforts used to control mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks have included treatment of infested trees with an organic arsenic pesticide, monosodium methanearsonate (MSMA). Cumulative pesticide applications over a large geographic area have generated concerns about arsenic loading in the environment and potential toxicity to nontarget wildlife. We investigated woodpecker foraging patterns in infested stands with and without MSMA treatment using a combination of tree debarking indices, point count surveys, and radiotelemetry methods in addition to insect flight traps to measure mountain pine beetle emergence. Debarking indices indicated woodpecker foraging of MSMA-treated trees was significantly lower than nontreated trees in all sampling years. However, approximately 40% of MSMA trees had some evidence of foraging. Focal observations of foraging woodpeckers and point count surveys in MSMA treatment areas further confirmed that several species of woodpeckers regularly used MSMA stands during the breeding season. Radio-tagged Hairy (Picoides villosus) and Three-toed (Picoides dorsalis) Woodpeckers spent on average 13% and 23% (range 0-66%) of their time, respectively, in treated stands, despite the fact that these areas only comprised on average 1-2% of their core home range (1 km2). MSMA strongly reduced the emergence of several bark beetle (Coleoptera, Scolytidae) species including the mountain pine beetle, and there was a highly significant positive relationship between Dendroctonus beetle abundance and Three-toed Woodpecker abundance. This study identifies the potential negative impact that forest management practices using pesticides can have on woodpecker populations that depend on bark beetles and their host trees.