313 research outputs found
Langzeitanalyse der Polizeilichen Kriminalstatistik und Auswertung von Strafverfahrensakten
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The Influence of Model Resolution on the Simulated Sensitivity Of North Atlantic Tropical Cyclone Maximum Intensity to Sea Surface Temperature
Methodological Advances to Study Contaminant Biotransformation: New Prospects for Understanding and Reducing Environmental Persistence?
Complex microbial communities in environmental systems play a key role in the detoxification of chemical contaminants by transforming them into less active metabolites or by complete mineralization. Biotransformation, i.e., transformation by microbes, is well understood for a number of priority pollutants, but a similar level of understanding is lacking for many emerging contaminants encountered at low concentrations and in complex mixtures across natural and engineered systems. Any advanced approaches aiming to reduce environmental exposure to such contaminants (e.g., novel engineered biological water treatment systems, design of readily degradable chemicals, or improved regulatory assessment strategies to determine contaminant persistence a priori) will depend on understanding the causal links among contaminant removal, the key driving agents of biotransformation at low concentrations (i.e., relevant microbes and their metabolic activities), and how their presence and activity depend on environmental conditions. In this Perspective, we present the current understanding and recent methodological advances that can help to identify such links, even in complex environmental microbiomes and for contaminants present at low concentrations in complex chemical mixtures. We discuss the ensuing insights into contaminant biotransformation across varying environments and conditions and ask how much closer we have come to designing improved approaches to reducing environmental exposure to contaminants
Compound-specific isotope analysis of benzotriazole and its derivatives
Compound-specific isotope analysis (CSIA) is an important tool for the identification of contaminant sources and transformation pathways, but it is rarely applied to emerging aquatic micropollutants owing to a series of instrumental challenges. Using four different benzotriazole corrosion inhibitors and its derivatives as examples, we obtained evidence that formation of organometallic complexes of benzotriazoles with parts of the instrumentation impedes isotope analysis. Therefore, we propose two strategies for accurate C and N measurements of polar organic micropollutants by gas chromatography isotope ratio mass spectrometry (GC/IRMS). Our first approach avoids metallic components and uses a Ni/Pt reactor for benzotriazole combustion while the second is based on the coupling of online methylation to the established GC/IRMS setup. Method detection limits for on-column injection of benzotriazole, as well as its 1-CH -, 4-CH -, and 5-CH -substituted species were 0.1-0.3mM and 0.1-1.0mM for δ13C and δ15N analysis respectively, corresponding to injected masses of 0.7-1.8 nmol C and 0.4-3.0 nmol N, respectively. The Ni/Pt reactor showed good precision and was very long-lived ( 1000 successful measurements). Coupling isotopic analysis to offline solid-phase extraction enabled benzotriazole-CSIA in tap water, wastewater treatment effluent, activated sludge, and in commercial dishwashing products. A comparison of C and N values from different benzotriazoles and benzotriazole derivatives, both from commercial standards and in dishwashing detergents, reveals the potential application of the proposed method for source apportionmen
Burial condition is the most important factor for mtDNA PCR amplification success in Palaeolithic equid remains from the Alpine foreland
Faunal remains from Palaeolithic sites are important genetic sources to study preglacial and postglacial populations and to investigate the effect of climate change and human impact. Post mortem decay, resulting in fragmented and chemically modified DNA, is a key obstacle in ancient DNA analyses. In the absence of reliable methods to determine the presence of endogenous DNA in sub-fossil samples, temporal and spatial surveys of DNA survival on a regional scale may help to estimate the potential of faunal remains from a given time period and region. We therefore investigated PCR amplification success, PCR performance and post mortem damage in c. 47,000 to c. 12,000-year-old horse remains from 14 Palaeolithic sites along the Swiss Jura Mountains in relation to depositional context, tissue type, storage time and age, potentially influencing DNA preservation. The targeted 75 base pair mitochondrial DNA fragment could be amplified solely from equid remains from caves and not from any of the open dry and (temporary) wetland sites. Whether teeth are better than bones cannot be ultimately decided; however, both storage time after excavation and age significantly affect PCR amplification and performance, albeit not in a linear way. This is best explained by the—inevitable—heterogeneity of the data set. The extent of post mortem damage is not related to any of the potential impact factors. The results encourage comprehensive investigations of Palaeolithic cave sites, even from temperate regions
Assessing the links between childhood trauma, C-reactive protein and response to antidepressant treatment in patients with affective disorders
Adverse Childhood Experiences (ACE) are a well-known risk-factor for depression. Additionally, (high-sensitive) C-reactive Protein (hsCRP) is elevated in subgroups of depressed patients and high following ACE. In this context the literature considers hsCRP and ACE to be associated with treatment resistant depression. With the data being heterogenous, this study aimed to explore the associations of ACE, hsCRP levels and response to antidepressant treatment in uni- and bipolar depression. N = 76 patients diagnosed with uni- or bipolar depression and N = 53 healthy controls were included. Treatment was over 6~weeks in an inpatient psychiatric setting within an observatory study design. Depressive symptoms were assessed by the Montgomery-Asberg Depression Rating Scale (MADRS), ACE were assessed by the Childhood Trauma Questionnaire (CTQ); the body-mass-index (BMI) and hsCRP were measured. HsCRP levels did not differ between the study population and the healthy controls. While the depressive symptoms decreased, the hsCRP levels increased. Sexual abuse was associated with significant higher and emotional abuse with lower levels of hsCRP after 6~weeks. The baseline hsCRP levels and the ACE subgroups did not~show significant associations with the treatment response in unipolar depressed patients. The long-lasting effects of specific forms of ACE may have relevant impact on inflammation, supporting hsCRP to be a suitable biomarker. With ACE and hsCRP not showing any significant associations with treatment response in the unipolar depressed subgroup, a more differentiate research concerning biomarkers and treatment regimens is needed when talking about treatment response
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