47 research outputs found

    Genetic Determinants of Time Perception Mediated by the Serotonergic System

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    Background: The present study investigates neurobiological underpinnings of individual differences in time perception. Methodology: Forty-four right-handed Russian Caucasian males (18–35 years old) participated in the experiment. The polymorphism of the genes related to the activity of serotonin (5-HT) and dopamine (DA)-systems (such as 5-HTT, 5HT2a, MAOA, DAT, DRD2, COMT) was determined upon the basis of DNA analysis according to a standard procedure. Time perception in the supra-second range (mean duration 4.8 s) was studied, using the duration discrimination task and parametric fitting of psychometric functions, resulting in individual determination of the point of subjective equality (PSE). Assuming the ‘dual klepsydra model ’ of internal duration representation, the PSE values were transformed into equivalent values of the parameter k (kappa), which is a measure of the ‘loss rate ’ of the duration representation. An association between time representation parameters (PSE and k, respectively) and 5-HT-related genes was found, but not with DArelated genes. Higher ‘loss rate ’ (k) of the cumulative duration representation were found for the carriers of genotypes characterized by higher 5-HT transmission, i.e., 1) lower 5-HT reuptake, known for the 5-HTTLPR SS polymorphism compared with LL, 2) lower 5-HT degradation, described for the ‘low expression ’ variant of MAOA VNTR gene compared with ‘high expression ’ variant, and 3) higher 5-HT2a receptor density, proposed for the TT polymorphism of 5-HT2a T102C gene compared with CC

    Degradation of haloaromatic compounds

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    An ever increasing number of halogenated organic compounds has been produced by industry in the last few decades. These compounds are employed as biocides, for synthetic polymers, as solvents, and as synthetic intermediates. Production figures are often incomplete, and total production has frequently to be extrapolated from estimates for individual countries. Compounds of this type as a rule are highly persistent against biodegradation and belong, as "recalcitrant" chemicals, to the class of so-called xenobiotics. This term is used to characterise chemical substances which have no or limited structural analogy to natural compounds for which degradation pathways have evolved over billions of years. Xenobiotics frequently have some common features. e.g. high octanol/water partitioning coefficients and low water solubility which makes for a high accumulation ratio in the biosphere (bioaccumulation potential). Recalcitrant compounds therefore are found accumulated in mammals, especially in fat tissue, animal milk supplies and also in human milk. Highly sophisticated analytical techniques have been developed for the detection of organochlorines at the trace and ultratrace level

    Historical Pollution: In Search of a Legal Definition

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    The chapter introduces and investigates the concept of \u201chistorical pollution\u201d in the context of environmental law. The subject is complex, as the principal consideration in our analysis concerns the role of time in the causation of harmful consequences (both for the environment and human health), notably in view of the prolonged timeframe that separates the conduct (pollution) and the effect (contamination). The phenomenon under scrutiny has significant implications for both the legal and the social fields. Indeed, legal enforcement of putative crimes against the environment is generally ineffective precisely because of this temporal factor, and this also has consequences for social perceptions and the dynamics of victimization. Yet these considerations could also contribute to a definition of historical pollution, as\u2014 given the complexity and uncertainties that surround the phenomenon\u2014they suggest ways in which material cases could be used to frame a general understanding of the concept. Attention here is focused on pollution related to industrial activities since such cases are prominent in the field. The proposed definition strives to establish a general framework within which domestic analyses can be located, consistent with the particularities of each legal system. It represents one of the first steps into the unexplored terrain of historical pollution
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