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At least 181 records · Page 10Linked to original sources
PubMed1997

Deconstructing the myth of the neutral analyst: an alternative from intersubjective systems theory.

A critique is offered of four conceptions of neutrality that have been prominent in the psychoanalytic literature: neutrality as (1) abstinence, (2) anonymity, (3) equidistance, and (4) empathy. It is argued that once the psychoanalytic situation is recognized as an intersubjective system of reciprocal mutual influence, the concept of neutrality is revealed to be an illusion. Hence, interpretations are always suggestions, transference is always contaminated, and analysis are never objective. An alternative to neutrality is found in the investigatory stance of empathic-introspective inquiry. This mode of inquiry is sharply distinguished from the prescribing of self-expressive behavior on the part of analysis, and the distinction is illustrated with a clinical vignette.

Adult↗
PubMed2005

Modified isotope pairing technique to study N transformations in polluted aquatic systems: theory.

Denitrification of nitrate in sediments of polluted aquatic systems has the potential to release considerable nitrogen amounts into the atmosphere in the form of dinitrogen (N2) and/or nitrous oxide (N2O). Nitrate may diffuse into the anoxic sediment layer either from the oxic sediment layer (after being produced there by nitrifiers) or directly from the overlying water. Currently, the most common technique that explicitly distinguishes between the two main nitrate sources is the Isotope Pairing Technique (IPT). 15N-labeled nitrate is added to the water column, and formation of 15N labeled N2 molecules is subsequently monitored. The main shortcoming of the IPT is that the formation of N20 is ignored, thus resulting in an underestimation of sediment denitrification. Another limitation is the inability to account for a possible influx of nitrate through the hyporheic zone (e.g., nitrate-polluted groundwater) into the anoxic sediment layer. We have further developed and analyzed the theoretical basis of the original IPT. The two important factors that we took into account are the isotopic composition of N20 and the input of an external source of nitrate. We also examined the option of adding 15N-labeled ammonium to the water column to specifically adjustthe technique to field studies. The presented modified technique allows us to (i) improve the estimation of sediment denitrification capacity, (ii) gain an insight into the N20 formation mechanism(s) and fluxes, and (iii) assess inputs of nitrate-polluted water through the hyporheic zone.

Environmental Monitoring↗
PubMed2005

Surface-directed capillary system; theory, experiments and applications.

We present a capillary flow system for liquid transport in microsystems. Our simple microfluidic system consists of two planar parallel surfaces, separated by spacers. One of the surfaces is entirely hydrophobic, the other mainly hydrophobic, but with hydrophilic pathways defined on it by photolithographic means. By controlling the wetting properties of the surfaces in this manner, the liquid can be confined to certain areas defined by the hydrophilic pathways. This technique eliminates the need for alignment of the two surfaces. Patterned plasma-polymerized hexafluoropropene constitutes the hydrophobic areas, whereas the untreated glass surface constitutes the hydrophilic pathways. We developed a theoretical model of the capillary flow and obtained analytical solutions which are in good agreement with the experimental results. The capillarity-driven microflow system was also used to pattern and immobilize biological material on planar substrates: well-defined 200 microm wide strips of human cells (HeLa) and fluorescence labelled proteins (fluorescein isothiocyanate-labelled bovine serum albumin, i.e., FITC-BSA) were fabricated using the capillary flow system presented here.

Adsorption↗
PubMed2006

Chaotic dynamics in simple neuronal systems: theory and applications.

The ubiquitous feature of the nervous system of wide spread occurrence of complex dynamics behaviour is treated. The cardinal question concerning the nature of generators of such complex behaviour, namely if it is ad hoc random or deterministic but strongly nonlinear, is analyzed. It is proved analytically that the discrete dynamics of single neurons with the sigmoidal transfer function is potentially chaotic. As the by-product the functional gain-threshold mechanism in neurons is derived. This allows for the new interpretations of famous experiments by Miyashita on squirell monkeys. Then it is shown that the continuous dynamics of the neural circuits of two-three neurons are endowed with the potentiality of chaotic firing, too. Finally, it will be argued that the classical dogma of stochastic or the ad hoc random neural coding can be taken as the limiting case of presenting new approach of deterministic or chaotic paradigm.

Animals↗