Commissioned by the Ministry for the Environment Baden-Württemberg a proficiency testing on the analysis of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) was ...carried out. With sixty participating laboratories from eight countries, mainly from the Federal Republic of Germany, this study is the largest proficiency testing in the field of dioxin analysis ever organised. In the study involved were the determination of the seventeen 2,3,7,8-substituted PCDD/PCDF congeners, the toxicity equivalent according to NATO/CCMS (I-TEQ) and of the homologue groups of the tetra- to heptaCDD/CDF. The laboratories were instructed to use their preferred method of clean-up and quantitative determination of PCDD/PCDF. No significant influence of the type of mass spectrometric equipment (high or low resolution GC/MS) or of the type of capillary column (polar and/or non-polar) or any combination of capillary columns upon the quality of the analysis measured by the z-score of the I-TEQ values is apparent. According to a proposal of the IUPAC and derived from the Ordinance on Sewage Sludge (AbfKlärV), the fulfilment of the Q-score and the ‘z-score 75 %’ was defined as the decisive quality criterion for successful participation in the proficiency test. 41 participants (according to 68 %) met this quality criterion for both sewage sludge samples.
Zusammenfassung
Fetale Prägung beschreibt den Zusammenhang zwischen dem Einfluss exogener und endogener Faktoren in sensiblen Phasen der Fetalentwicklung und dem Zellwachstum und der ...Organentwicklung, letztendlich mit dem Resultat einer anhaltenden postnatalen Veränderung in Organ- und Gewebsfunktionen. Hierbei kann eine Fehlanpassung mit dem Auftreten von Erkrankungen im gesamten späteren Leben assoziiert sein. Suboptimale intrauterine Bedingungen, wie etwa maternale Fehlernährung, Hypoxie, psychischer Stress oder aber die GC(Glukokortikoid)-Exposition, können die fetale Entwicklung nachhaltig beeinflussen und sind häufig mit einer Verringerung des Geburtsgewichts assoziiert. Das mögliche Spektrum der Spätfolgen ist hierbei weit gefächert. Die antenatale Behandlung mit GC scheint mit einer geschlechtsspezifischen fetalen Wachstumsrestriktion sowie strukturellen und funktionellen Veränderungen in der Plazenta assoziiert zu sein, die potenziell die Gesundheit im späteren Leben beeinflussen können. Während bei den weiblichen Feten eine eher kontinuierliche Sensibilität gegenüber GC zu bestehen scheint, möglicherweise im Sinne einer präferentiellen Überlebensstrategie zur Sicherung der Reproduktionsfähigkeit mit Spezieserhalt, scheint bei männlichen Feten nach GC-Exposition die Plazenta zumindest temporär eine Resistenz gegenüber GC zu entwickeln. Die geschlechtsspezifische Sensibilität gegenüber GC wird vermutlich durch ein unterschiedliches GR(GC-Rezeptoren)-Verteilungsmuster, Expression und/oder Interaktion verursacht und durch die Behandlung mit GC beeinflusst. Ein verbessertes Verständnis für die plazentavermittelten Signalwege, die zur fetalen Programmierung beitragen, wird von entscheidender Bedeutung bei den Bemühungen sein, interventionelle Strategien für Risikogruppen zu entwickeln.
Interpretation of acoustic seismic records have allowed mapping of shallow gas accumulations and gas escape features in the Rias Baixas. X-ray photographs and voids of cores are semi-direct evidence ...of gassy sediments. Mapping of fluid-escape areas shows that these are related to the gas accumulations or at the intersections of faults. Analyses (GC-MS) of bubble samples collected in Simon Bay (Ria de Vigo) and across the whole ria confirm the presence of methane. The spatial distribution of gas escapes/accumulations and their vertical variations are interpreted as evidence of sedimentary facies control. The appearance of authigenic minerals (gypsum, pyrite and aragonite) and microbiological activity related to the seal facies are taken as evidence of the biogeochemical coupling processes. It is evident that these shallow-water coastal environments make significant contributions to the methane budget of the hydrosphere and atmosphere. It is also suggested that microbiological activity is favoured by gas escapes.
Elongating shoots of rapidly growing clones of Salix viminalis L. (clone 683-4) and Salix dasyclados Wimm. (clone 908) harvested in early August were analyzed for endogenous gibberellins (GA). ...Distribution of GA-like activity, determined by Tan-ginbozu dwarf rice microdrop bioassay after reverse phase C18 high performance chromatography, was similar for both species. For S. dasyclados, combined gas chromatography-selected ion monotoring (GC-SIM) yielded identifications of $\text{GA}_{1}$, $\text{GA}_{8}$, $\text{GA}_{19}$, $\text{GA}_{20}$, and $\text{GA}_{29}$. Identifications of GA4 and GA9 were also made using coinjections of known amounts of 17, 17-^{2}\text{H}{}_{2}$GAs. By bioassay, the main activity was $\text{GA}_{19}$-like in both species. Gibberellin A1, $\text{GA}_{19}$, and $\text{GA}_{20}$ concentrations were approximated by GC-SIM using co-injections of known amounts of 17,17-^{2}\text{H}{}_{2}$GAs. Both bioassay and GC-SIM results indicated very high concentrations of $\text{GA}_{19}$ and $\text{GA}_{20}$ (about 6000 nanograms per kilogram fresh weight shoot tissue using GC-SIM: 800 ng using bioassay), compared to the concentration of $\text{GA}_{1}$ (about 130 nanograms per kilogram fresh weight using either GC-SIM or bioassay).
The petrochemical industry generates series of liquid and solid wastes containing large amounts of priority pollutants during the petroleum-refining process. These residues must be treated through ...depuration processes. The bioremediation process, presenting countless advantages in relation to other processes employed, is an evolving method for the removal and the transformation of many environmental pollutants including those produced by the petroleum industry. In a first step, a continuously stirred tank bioreactor (CSTR) was used to optimize feasible and reliable bioprocess system for successful bioremediation of industrial effluent and to develop an efficient microbial consortium for the degradation of petroleum hydrocarbons. After an experimental period of 175 days, the process was shown to be highly efficient in decontaminating the wastewater. The performance of the bio augmented reactor was demonstrated by the reduction of COD rates up to 95%. Six microbial isolates from the CSTR were characterized and species identification was confirmed by sequencing the 16 S rRNA genes. Besides, the treated wastewater could be considered as non toxic according to the micro-toxicity test. In a second step, bioremediation of a refinery soil containing hydrocarbons climate was investigated. The objective of this study was to assess the ability of bioremediation technique in the presence of the acclimatized consortium to reduce the total petroleum hydrocarbon (TPH) content in the contaminated soil. Results clearly demonstrated that an enhanced bioremediation was carried when the acclimatized bacterial consortium was added to the hydrocarbons contaminated soil. The proposed bioremediation technology has proved significantly higher hydrocarbons removal efficiencies. TPH analysis showed that 50% of the hydrocarbons were eliminated during the first 15 days of bio remediation. TPH removal reached 96% at the end of the treatment. Further, GC/MS profile has proved that the acclimatized bacterial consortium could effectively remove the medium- and long-chain alkanes in the contaminated soil such as the alkanes were undetectable after a 30-day of incubation period. In a third step, a Halomonas sp. strain C2SS100 had been isolated and characterized from Sercina petroleum reservoir. The strain had shown potential hydrocarbon degradation under halophilic condition (100 g 1−1 NaCl). During growth on n-Hexadecane (C16), C2SS100 produced biosurfactant that could solubilise phenanthrene, a three-ring aromatic hydrocarbon. The halophilic character of this bacterium could add further advantages for its use in marine and saline environments-oil bioremediation.
The Kascade-Grande experiment Brüggemann, M.; Stümpert, M.; van Buren, J. ...
Neutrinos and Explosive Events in the Universe
Book Chapter
Odprti dostop
The KASCADE-Grande experiment measures extensive air showers induced by primary cosmic rays in the energy range 1014 – 1018 eV. The major motivation for KASCADE-Grande is the investigation of the so ...called ”knee” in the energy spectrum of cosmic rays and its presumed rigidity dependence. A short overview of the experimental setup with focus on the Grande array and its new data acquisition system is given. As an example of analysis the reconstruction of the total muon number is presented.
The cooperative effects in the substrate vapor binding by solid receptors and their relevance for structure-property relationships in the odor sensor applications are discussed and reviewed.
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