Intersection of microwire electrodes with proximal CA1 stratum-pyramidale neurons at insertion for multiunit recordings predicted by a 3-D computer model

It is of broad interest in the context of neuronal multiunit extracellular recordings to understand electrode-tissue interactions in order to maximize the number of recordable units and to minimize experimental artifacts due to mechanical tissue alteration. Toward this goal, a computer model of microwire electrode insertion in hippocampus CA1 area was developed, firstly to provide estimates of the number of electrode-neuron intersections affecting recordable (local) neurons and, secondly, to determine optimal insertion/electrode parameters that minimize the number of intersections. The model predicts that in hippocampus CA1 area, using an electrode 50 microm in diameter, only 10% of the recordable neurons (those within 50 microm of the electrode), would remain collision free. Moreover, the model also predicts that inhibitory neurons are less prone to be intersected by the electrode, resulting in a 2 to threefold higher percentage of collision-free interneurons than expected from the relative densities of pyramidal cells and interneurons. Furthermore, the model confirms, in agreement with experimental observations, that electrode tilting with respect to the main neuronal axis increases the number of intact neurons (fourfold for a 50-microm electrode at 45 degrees when compared to 0 degrees , i.e., an insertion normal to the cell body layer).     

Linkages between spouses' psychological distress and marital conflict in the home.

To elucidate the processes that underlie the established association between psychopathology and marital functioning, researchers have given attention to how symptomatic individuals manage their interpersonal contexts, particularly during the handling of disagreements. In the current study, the authors evaluate the role of marital conflict strategies in relation to wives' and husbands' psychological distress levels. A sample of 100 community-based couples completed assessments of psychological distress and diaries describing marital conflict that occurred at home during a 15-day reporting period. Findings from multilevel modeling of dyadic data revealed associations between both spouses' psychological distress and multiple behavioral and emotional conflict expressions in the home. Psychological symptoms uniquely predicted the occurrence of certain conflict expressions, even when accounting for global negative marital sentiments. The findings encourage subsequent consideration of marital conflict expressions and resolution strategies when studying processes involved in the marriage-psychological adjustment link. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The aditi deductive database system

Deductive databases generalize relational databases by providing support for recursive views and non-atomic data. Aditi is a deductive system based on the client-server model; it is inherently multi-user and capable of exploiting parallelism on shared-memory multiprocessors. The back-end uses relational technology for efficiency in the management of disk-based data and uses optimization algorithms especially developed for the bottom-up evaluation of logical queries involving recursion. The front-end interacts with the user in a logical language that has more expressive power than relational query languages. We present the structure of Aditi, discuss its components in some detail, and present performance figures.     

Current and voltage based bit errors and their combined mitigation for the Kirchhoff-law–Johnson-noise secure key exchange

We classify and analyze bit errors in the current measurement mode of the Kirchhoff-law–Johnson-noise (KLJN) key distribution. The error probability decays exponentially with increasing bit exchange period and fixed bandwidth, which is similar to the error probability decay in the voltage measurement mode. We also analyze the combination of voltage and current modes for error removal. In this combination method, the error probability is still an exponential function that decays with the duration of the bit exchange period, but it has superior fidelity to the former schemes.     

Romantic partners' individual coping strategies and dyadic coping: Implications for relationship functioning.

Individual coping strategies and dyadic coping independently predict partner well-being and relationship functioning; however, it is unclear whether the coping processes are inter-related and whether they uniquely contribute to romantic relationship functioning. One hundred heterosexual dating couples rated the individual coping strategy of negative mood regulation as well as positive and negative dyadic coping. Relationship functioning was assessed via partners' reports of relationship satisfaction and observers' ratings of negative interaction in conflict. Actor-Partner Interdependence Models (APIMs; Cook & Kenny, 2005; Kashy & Kenny, 2000) revealed associations between individual coping and dyadic coping in the predicted directions. APIMs also indicated the unique contributions of positive and negative dyadic coping to relationship functioning, above and beyond contributions of individual coping strategies. Implications of dyadic coping as a target of efforts to prevent or treat partner and/or relational distress are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thermal dynamic model of precision wire-wound resistors

Wire-wound type resistors are often used as reference elements in high-precision electronic instruments of industrial frequencies (50-60 Hz). One of the main factors in the measurement uncertainty of these instruments is the "self-heating" affected drift of the built-in wire-wound resistors. The materials, geometry, construction and the thermal environment of the resistors determine the dynamics of the load-affected drift. This paper investigates a thermal model that can be used for on-line estimation of the load-affected thermal dynamic drift of commercially available encapsulated precision wire-wound resistors. Using the suggested model, the achievable estimation error of the relative change in resistance is below 10%. The model and the model-based on-line error estimation allow reducing the measurement uncertainty of industrial high-precision calibrators and extending the power range of standard resistors in laboratories.     

Simultaneous biohydrogen production and wastewater treatment based on the selective enrichment of the fermentation ecosystem

Biohydrogen production from synthetic wastewater as substrate was studied in anaerobic small scale batch reactors. Enriched anaerobic mixed consortia sampled from various environments were used as parent inocula to start the bioreactors. Selective enrichments were achieved by various physical and chemical pretreatments and changes in the microbial communities were monitored by metagenomic and molecular diagnostics approaches. Experimental data showed the feasibility of biohydrogen production using synthetic wastewater as substrate. The hydrogen generation capability of the different mixed consortia is clearly dependent on the pretreatment methods. The described approach opens the possibility for an alternative way towards simultaneous wastewater treatment and renewable energy generation.