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21.
We reported previously that trichodiene, a volatile trichothecene derivative, was produced by a Stachybotrys isolate, also known to produce highly cytotoxic, non-volatile, macrocyclic trichothecenes (satrotoxins). We investigated the relationship between the production of trichodiene and various non-volatile trichothecenes for several molds. Volatile metabolites were concentrated by adsorption on Tenax TA and analyzed by GC/MS, while non-volatile metabolites were separated by HPLC, derivatized and analyzed by GC/MS. Stachybotrys chartarum isolates producing macrocyclic trichothecenes secreted significantly larger amounts of trichodiene and other sesquiterpenes than isolates which only produced simple trichothecenes. The amounts of secreted trichodiene were relatively small in all cases. With the exception of Memnoniella, which excreted small amounts of sesquiterpenes, the other isolates produced varying amounts of sesquiterpenes, including trichodiene, as well as simple tricothecenes, no detectable trichodiene, but large amounts of griseofulvin derivatives. In Stachybotrys there is apparently a correlation between trichodiene and macrocyclic trichothecene production. In the remaining isolates, there was no simple relationship between trichodiene and non-volatile trichothecene synthesis. Trichodiene is produced in larger amounts by Stachybotrys isolates, which also produce satratoxins, but it will be difficult to utilize this metabolite to detect toxic isolates in buildings due to the relatively small amounts excreted.  相似文献   
22.
We examined the dark survival strategy of the cold-water dinoflagellate Scrippsiella hangoei from the Baltic Sea. Cultures of S. hangoei were placed in dark and light and we followed the morphological developmentand, determined respiration rate and activity of extracellular leucine aminopeptidase (LAP). S. hangoei had LAP activity in the light, but not in the dark, suggesting that the degradation and use of organic substrates is not part of the dark survival strategy. After prolonged time in darkness (>5 days), S. hangoei started to shed flagella and theca, and produced a previously undescribed temporary cyst. The transformation from vegetative cell into the temporary cyst initially increased respiration rate tenfold, but after the transformation the respiration rate decreased to almost undetectable levels. The presented temporary cyst enables survival through long periods in dark by reducing the respiration rate.  相似文献   
23.
It is generally accepted that viral particles in source water are likely to be found as aggregates attached to other particles. For this reason, it is important to investigate the disinfection efficacy of chlorine on aggregated viruses. A method to produce adenovirus particle aggregation was developed for this study. Negative stain electron microscopy was used to measure aggregation before and after addition of virus particles to surface water at different pH and specific conductance levels. The impact of aggregation on the efficacy of chlorine disinfection was also examined. Disinfection experiments with human adenovirus 2 (HAdV2) in source water were conducted using 0.2 mg/L free chlorine at 5 °C. Aggregation of HAdV2 in source water (≥3 aggregated particles) remained higher at higher specific conductance and pH levels. However, aggregation was highly variable, with the percentage of particles present in aggregates ranging from 43 to 71 %. Upon addition into source water, the aggregation percentage dropped dramatically. On average, chlorination CT values (chlorine concentration in mg/L × time in min) for 3-log10 inactivation of aggregated HAdV2 were up to three times higher than those for dispersed HAdV2, indicating that aggregation reduced the disinfection rate. This information can be used by water utilities and regulators to guide decision making regarding disinfection of viruses in water.  相似文献   
24.
Metal recovery is an essential part of the recycling of hybrid electric vehicle battery waste and the first step in a hydrometallurgical treatment is dissolution of the solid material. The properties of separated battery electrode materials were investigated. Focus was put on both the solid waste and then the dissolution behaviour. The cathode contains metallic nickel that remains undissolved when utilizing non-oxidizing conditions such as hydrochloric or sulphuric acid in combination with a low oxygen atmosphere. In these conditions the cathode active electrode material is fully dissolved. Not dissolving the nickel metal saves up to 37% of the acid consumption for the cathode electrode material. In the commonly used case of oxidizing conditions the nickel metal dissolves and a cobalt-rich phase remains undissolved from the cathode active material. For the anode material a complete and rapid dissolution can be achieved at mild conditions with hydrochloric, nitric or sulphuric acid. Optimal parameters for all cases of dissolution was pH 1 with a reaction time of approximately ?20,000 s.  相似文献   
25.
26.
Demersal fish cannot readily be tracked using satellite-based or light-based geolocation techniques. As an alternative, we describe the tidal location method, which uses tidal data recorded by electronic data storage tags (DSTs), to determine geoposition. Times of high water (H) and tidal ranges (R) recorded by DSTs moored at known locations, and from free-swimming tagged plaice, Pleuronectes platessa, were compared with a North Sea tidal database to identify all positions with matching values of H and R. Within the recording precision of the tag (ǂ.2 m, ᆞ min) and the predicted accuracy of the model generated tidal data (ǂ.15 m, ᆨ min), geolocations over much of the North Sea and eastern English Channel were predicted to be accurate to within 40 km, sometimes to within 10 km. Positional estimates of the moored tags were within 15.7Dž.5 km of the actual locations. Geolocations made from tagged plaice within 5 days of release and 5 days pre-recapture were within 35ᆬ km and 37ᆫ km of release and recapture positions respectively. Our results demonstrate the ability of this method to accurately describe the migrations of North Sea plaice throughout their geographical range with a level of accuracy unattainable using light-based geolocation. The method could equally be applied to any shelf-dwelling demersal fish that periodically rests on the sea-bed for the duration of a tidal cycle. In fisheries management, the method has clear potential application in defining the movements and migrations of other commercial species.  相似文献   
27.
Objectives: The objective of this study was to examine the frequency of psychoactive drugs and alcohol in drivers under suspicion of driving under the influence of drugs and alcohol in 2015 and 2016 in the eastern part of Denmark. The trends in the number of traffic cases sent for drug analysis since 2000 and alcohol analysis since 2011 are also discussed.

Methods: Blood samples from drivers suspected of being under the influence of alcohol and/or medication and/or illicit drugs in 2015 and 2016 were investigated as requested by the police. The blood samples were screened for alcohol and/or tetrahydrocannabinol (THC) alone, for other drugs (covering all drugs, except THC, listed in the Danish list of narcotic drugs), or for THC and other drugs. Age and gender were also recorded. The number of drug traffic cases since 2000 and the number of alcohol cases since 2011 were extracted from our Laboratory Information Management System (LIMS).

Results: In total, 11,493 traffic cases were investigated. Alcohol and/or drugs exceeded the legal limit in 9,657 (84%) cases. Men constituted 95% of the drivers investigated for drugs and 88% of the alcohol cases. The drivers investigated for drugs consisted primarily of young men, whereas drivers investigated for alcohol were older.

The frequency was higher for positive alcohol cases above the legal limit (87%) than for drug cases (76%) above the fixed concentration limit. THC (67–69%) was the most frequently detected drug above the legal limit, followed by cocaine (27–28.5%), amphetamine (17%), and clonazepam (6–7%) in both years. Morphine (5.4%), included among the 5 most frequent drugs in 2015, was replaced by methadone (4.6%) in 2016. Few new psychoactive drugs (NPS) were detected.

The number of traffic cases sent for drug analysis has increased more than 30-fold since 2000–2006, and the number of traffic cases submitted in 2016 for drug analysis was higher than the number for alcohol analysis; the latter has decreased since 2011.

Conclusion: Overall, alcohol was the most frequent compound detected above the legal limit in both years, followed by the well-known illicit drugs THC, cocaine, and amphetamine. NPS were seldom seen. One consequence of the increased focus on drugs in traffic has been an immense increase in drug traffic cases sent for analysis since 2006 in the eastern part of Denmark. Although this survey revealed only minimal changes compared to earlier investigations, surveys like this are invaluable for monitoring abuse patterns and trends in drugged and drunken driving.  相似文献   

28.
Urban displacement is frequently portrayed as a new and unfamiliar dilemma for the humanitarian sector, yet broad awareness of its characteristics and challenges has been developing since the 1970s. In the past decade, however, there has been greater attention to, and recognition of, the implications of rapid urbanisation in the developing world. This has led to some policy development and a mounting body of NGO (non-governmental organisation) and think-tank literature on the topic. Assuming displacement to be a key lens on urban vulnerability more broadly, this paper presents an overview of the historical development of debates on urban displacement since the 1970s. Drawing examples from the contributions in this special issue of Disasters, as well as from other sources of information on recent humanitarian responses in various contexts, it assesses the ramifications of urban vulnerability for humanitarian practitioners. The paper contends that the humanitarian sector has failed to galvanise on the issue, and has struggled therefore to employ existing knowledge and to adapt practice.  相似文献   
29.
Dewatered municipal biosolids (DMBs) were applied to a field at a rate of ~22 Mg dw ha(-1) in October 2008. Pharmaceuticals and personal care products (PPCPs) were monitored in groundwater, tile drainage, soil, DMB aggregates incorporated into the soil post-land application, and in the grain of wheat grown on the field for a period of ~1 year following application. Over 80 PPCPs were analyzed in the source DMB. PPCPs selected for in-depth monitoring included: antibiotics (tetracyclines, fluoroquinolones), bacteriocides (triclosan, triclocarban), beta-blockers (atenolol, propranolol, metaprolol), antidepressants (fluoxetine, citalopram, venlafaxine, sertraline), antifungals (miconazole), analgesics (acetaminophen, ibuprofen) and anticonvulsants (carbamazepine). PPCPs in tile were observed twice, ~3 weeks and 2 months post-application. Of all PPCPs measured in tile drainage, only carbamazepine, ibuprofen, acetaminophen, triclosan, triclocarban, venlafaxine, and citalopram were detected (5-74 ng L(-1)). PPCPs were not detected in groundwater >2 m depth below the soil surface, and concentrations above detection limits at 2 m depth were only observed once just after the first rain event post-application. In groundwater, all compounds found in tile, except carbamazepine, acetaminophen and citalopram, were detected (10-19 ng L(-1)). PPCPs were detected in DMB aggregates incorporated in soil up to 1 year post-application, with miconazole and fluoxetine having the lowest percent reductions over 1 year (~50%). For several compounds in these aggregates, concentration declines were of exponential decay form. No PPCPs were detected in the grain of wheat planted post-application on the field. No PPCPs were ever detected in water, soil or grain samples from the reference plot, where no DMB was applied.  相似文献   
30.
Proponents of using genetically modified (GM) crops and food in the developing world often claim that it is unjust not to use GMOs (genetically modified organisms) to alleviate hunger and malnutrition in developing countries. In reply, the critics of GMOs claim that while GMOs may be useful as a technological means to increase yields and crop quality, stable and efficient institutions are required in order to provide the benefits from GMO technology. In this debate, the GMO proponents tend to rely on a simple utilitarian type of calculus that highlights the benefits of GMOs to the poor, but that overlooks the complex institutional requirements necessary for GMO production. The critics, recognizing the importance of institutional conditions, focus primarily on the negative impacts of institutional deficiencies, thereby overlooking the basically Rawlsian claim that institutions per se may generate claims to justice. This article investigates how GMOs might generate claims to global justice and what type of justice is involved. The paper argues that the debate on GMOs and global justice can be categorized into three views, i.e., the cosmopolitan, the pluralist, and the sceptic. The cosmopolitan holds that GMOs can and should be used for alleviating global hunger, whereas the sceptic rejects this course of action. I will argue here for a moderately cosmopolitan approach, relying on the pluralist view of institutions and the need to exploit the benefits of GMOs. This argument rests on the premise that global cooperation on GMO production provides the relevant basis for assessing the use of GMOs by the standard of global distributive justice.  相似文献   
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