The role of positive emotion in the therapeutic process of family therapy.

Historically, the role of positive emotions has been somewhat obscured in family therapy by focus on relational processes, behavioral sequences, and interactional patterns. Despite increasing interest in the role of positive emotions in the field of psychology, little attention has been given to these issues in family therapy. As a result, the specific role of positive emotions is neither theoretically nor clinically well understood. The authors analyze the role of positive emotions in Functional Family Therapy, a model in which positive emotions serve as a key element in the proximal and distal outcomes of the phase-based systematic change process. The authors suggest that the important question is not if but how positive emotions are important. It is apparent that positive emotions play a vital role in family therapy. However, the authors are only beginning to uncover the abundant complexities tied to the therapeutic role of positive emotions within the relational patterns of families. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nuclear heat for hydrogen production: Coupling a very high/high temperature reactor to a hydrogen production plant

Hydrogen has been dubbed the fuel of the future. As fossil fuel reserves become depleted and greenhouse gas emissions are reduced inline with the Kyoto protocol, alternative energy sources and vectors, such as hydrogen, must be developed. Hydrogen produced from water splitting, as opposed to from hydrocarbons, has the potential to be a carbon neutral energy solution. There are several methods to extract hydrogen from water, three leading candidates being high temperature electrolysis, the SI thermochemical cycle and the HyS hybrid thermochemical cycle. All three of these processes involve a section requiring very high temperatures. The Very High Temperature Reactor (VHTR), a gas cooled Generation IV reactor, is ideally suited for providing this high temperature heat. Nuclear hydrogen production is being investigated around the world. The four leading consortiums are the Japan Atomic Energy Agency (JAEA), PBMR/Westinghouse, GA, and AREVA NP/CEA/EDF. There are also many smaller R&D efforts focussing on the development of particular materials and components and on process flowsheeting.A nuclear hydrogen plant involves four key pieces of equipment: the VHTR, the hydrogen production plant (HPP), the intermediate heat exchanger (IHX) and the power conversion system (PCS). The choice of all four items varies dramatically between programmes. Both pebble bed and prismatic fuel block VHTRs are being developed, which can be directly or indirectly coupled to a HPP and PCS placed either in series or parallel. Either a Rankine steam cycle or a Brayton gas turbine cycle can be employed in the PCS. This report details the choices made and research being carried out around the world.Predicted process efficiencies and plant costs are currently at a preliminary stage and are very similar, regardless of the options chosen. The cost of hydrogen produced from water splitting using nuclear technologies is around $2/kg H₂. This is competitive with hydrogen produced by other methods, particularly if carbon emissions are regulated and costed. The technological feasibility and testing of key components will be one of the determining factors in plant viability.     

Overgeneral autobiographical memory in depressed adolescents with, versus without, a reported history of trauma.

Autobiographical memory retrieval is fundamental to the developing self-concept in adolescence, to emotion regulation, and to social problem solving and has been shown to be compromised in adolescents diagnosed with depression (R. J. Park, I. M. Goodyer, & J. D. Teasdale, 2002). The authors of the present study assessed autobiographical memory overgenerality in a sample of depressed adolescent participants with, versus without, a reported history of trauma and never-depressed control participants by using an emotion word-cueing paradigm. The authors' analyses showed for the first time that adolescents with major depression and with no reported history of trauma exhibited an overgeneral memory bias. They also revealed that depressed adolescents who reported a history of trauma retrieved fewer overgeneral memories than did depressed adolescents who reported no history of trauma. Among depressed adolescents who reported a history of trauma, more severe posttraumatic stress symptoms were associated with less overgenerality. Possible accounts of these findings are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Optical design of a dual-polarization receiver for 220–280 GHz

A 220–280 GHz dual polarization receiver has been built for the James Clerk Maxwell Telescope. Schottky diode mixers cooled to ～15K by a closed-cycle refrigerator are used to give DSB noise temperatures of 300K and 420K in the two channels. The optical design is based on gaussian-beam optics, and is frequency independent; it allows the significant higher order gaussian modes to propagate unhindered, thus offering the prospect of very high aperture efficiency. The receiver includes a number of novel optical components, including a completely symmetric dual polarization Martin-Puplett interferometer, used as the L.O. injection diplexer; a dielectric waveplate used as an in-line variable polarization splitter; and a dual-polarization in-line tunable Fabry-Perot SSB filter. Measurements of the performance of the optical system are presented.     

Improved solvation routes for the Bunsen reaction in the sulphur iodine thermochemical cycle: Part II – Molecular solvent properties

Operating the Bunsen reaction in the presence of a molecular solvent has the potential to decrease the large excesses of water and iodine currently required and therefore to increase the efficiency of the sulphur iodine cycle. Tri-n-butyl phosphate (TBP) has been shown to extract HI into the solvent phase, however the TBP breaks down when treated thermally to recover the HI. Alternative solvents which also show a high extraction of HI, but that are stable in the presence of HI at high temperature, are needed. This paper investigates dibutylbutylphosphonate (DBBP) and Cyanex^® 923 as alternatives to TBP. Both DBBP and Cyanex^® 923 were shown to perform as well as or better than TBP against metrics including: HI extraction, H₂SO₄ extraction, SO₂ solubility and I₂ solubility. Using TGA, thermal recovery of the HI was not successful from DBBP, as the solvent broke down in a similar way to TBP. Small amounts of HI were recovered through distillation of Cyanex^® 923, however the yield was low. Partial success was achieved by backwashing the HI loaded Cyanex^® 923 with water. Further work is needed to assess the performance of the actual Bunsen reaction in each of these solvents and to find ways of recovering the HI from the solvent.     

Experimental Determination of Supermicrometer Particle Fate Subsequent to a Point Release within a Room under Natural and Forced Mixing

The fate of mono-dispersed fluorescein-tagged particles with nominal aerodynamic diameters 3 μ m and 14 μ m has been measured in a room-scale chamber under natural and forced mixing conditions. The mixing time scales were measured as the time to mixing of carbon monoxide tracer gas. In the forced mixing condition, 3-axis ultrasonic anemometry was used to determine the mean and fluctuating velocity for each vector component at 106 locations. Cumulative deposited fluorescein mass at 61 locations on the chamber floor showed size-dependent and mixing-dependent particle dispersion patterns. More uniform deposition was produced under conditions with relatively shorter mixing time scales, and longer particle settling time scales. A unique data set has been generated for the evaluation of particulate contaminant transport models.     

Phenomenological model of diffuse global and regional atrophy using finite-element methods

The main goal of this work is the generation of ground-truth data for the validation of atrophy measurement techniques, commonly used in the study of neurodegenerative diseases such as dementia. Several techniques have been used to measure atrophy in cross-sectional and longitudinal studies, but it is extremely difficult to compare their performance since they have been applied to different patient populations. Furthermore, assessment of performance based on phantom measurements or simple scaled images overestimates these techniques' ability to capture the complexity of neurodegeneration of the human brain. We propose a method for atrophy simulation in structural magnetic resonance (MR) images based on finite-element methods. The method produces cohorts of brain images with known change that is physically and clinically plausible, providing data for objective evaluation of atrophy measurement techniques. Atrophy is simulated in different tissue compartments or in different neuroanatomical structures with a phenomenological model. This model of diffuse global and regional atrophy is based on volumetric measurements such as the brain or the hippocampus, from patients with known disease and guided by clinical knowledge of the relative pathological involvement of regions and tissues. The consequent biomechanical readjustment of structures is modelled using conventional physics-based techniques based on biomechanical tissue properties and simulating plausible tissue deformations with finite-element methods. A thermoelastic model of tissue deformation is employed, controlling the rate of progression of atrophy by means of a set of thermal coefficients, each one corresponding to a different type of tissue. Tissue characterization is performed by means of the meshing of a labelled brain atlas, creating a reference volumetric mesh that will be introduced to a finite-element solver to create the simulated deformations. Preliminary work on the simulation of acquisition artefacts is also presented. Cross-sectional and longitudinal sets of simulated data are shown and a visual classification protocol has been used by experts to rate real and simulated scans according to their degree of atrophy. Results confirm the potential of the proposed methodology.     

Temporal and spatial trends of organochlorines and mercury in fishes from the St. Clair River/Lake St. Clair corridor,Canada

The temporal and spatial relationships of a suite of organochlorine contaminants and mercury were examined in various fish species of the St. Clair River/Lake St. Clair corridor, Canada, in order to evaluate the effectiveness of remediation efforts and to assess the risk to human and wildlife fish consumers. In Lake St. Clair, fish tissue concentrations of mercury, polychlorinated biphenyls (PCBs), octachlorostyrene (OCS), hexachlorobenzene (HCB), and dichlorodiphenyltrichloroethane (DDT) decreased consistently from the 1970s until the 1980s and 1990s, after which the rate of contaminant decline slowed or concentrations stabilized. This trend was consistent in up to 13 species (both young-of-the-year and adult fishes) comprising different trophic positions and dietary habits, suggesting that the changes were reflective of ambient conditions rather than food web processes. Elevated concentrations of mercury, PCBs, OCS, HCB, and DDT were detected in St. Clair River young-of-the-year spottail shiner compared with fish from Lake Huron, indicating that non-atmospheric inputs of these chemicals, likely originating from sediment, remain in the St. Clair River. Current concentrations of mercury and PCBs, and mercury, PCBs, and DDT remain of concern to human and wildlife fish consumers, respectively. Given that contaminant decreases have generally stabilized in fish, we suggest that further natural recovery of contaminants in St. Clair corridor fishes will be slow since contaminants will likely continue to be influenced by sediment levels.