Innovative psychological treatments for depression

A number of high-intensity psychosocial interventions have been shown to be as efficacious as and more enduring than medications in the treatment of nonpsychotic depression. Moreover, there have been important advances in the development of strategies to facilitate the selection of the best treatment for a given patient with a depression diagnosis. However, the demand for services is too great to be met by conventional high-intensity approaches alone. Some of the most exciting work in recent years has focused on the development of low-intensity approaches that can benefit many people and do so cost-effectively

Age and origin of enigmatic megaherbs from the subantarctic islands

Biogeographic relationships in the southern hemisphere have puzzled biologists for the last two centuries. Once joined to form the supercontinent Gondwana, Africa, Antarctica, Australia, New Zealand and South America are widely separated by the Pacific and Indian oceans. Sir Joseph Hooker was the first to suggest that Antarctica served as a corridor for plant migration not unlike the land-bridges in the northern hemisphere. While the Antarctic flora was largely erased by glaciation during the Pleistocene, at least some of these Antarctic plant communities found refuge on the subantarctic islands. Here we provide support for the hypothesis that giant herbs persisted in the subantactic islands prior to the onset of Pleistocene glaciation, then dispersed northward in response to glacial advance. Our findings provide further evidence that Antarctica has played a pivotal role in shaping southern hemisphere biogeography

Simulations of MHD Instabilities in Intracluster Medium Including Anisotropic Thermal Conduction

We perform a suite of simulations of cooling cores in clusters of galaxies in order to investigate the effect of the recently discovered heat flux buoyancy instability (HBI) on the evolution of cores. Our models follow the 3-dimensional magnetohydrodynamics (MHD) of cooling cluster cores and capture the effects of anisotropic heat conduction along the lines of magnetic field, but do not account for the cosmological setting of clusters or the presence of AGN. Our model clusters can be divided into three groups according to their final thermodynamical state: catastrophically collapsing cores, isothermal cores, and an intermediate group whose final state is determined by the initial configuration of magnetic field. Modeled cores that are reminiscent of real cluster cores show evolution towards thermal collapse on a time scale which is prolonged by a factor of ~2-10 compared with the zero-conduction cases. The principal effect of the HBI is to re-orient field lines to be perpendicular to the temperature gradient. Once the field has been wrapped up onto spherical surfaces surrounding the core, the core is insulated from further conductive heating (with the effective thermal conduction suppressed to less than 1/100th of the Spitzer value) and proceeds to collapse. We speculate that, in real clusters, the central AGN and possibly mergers play the role of "stirrers," periodically disrupting the azimuthal field structure and allowing thermal conduction to sporadically heat the core.Comment: 16 pages, 3 tables, 17 figures, accepted to ApJ with minor revisions, to appear in Volume 704, Oct 20, 2009 issu

Are tiled display walls needed for astronomy?

Clustering commodity displays into a Tiled Display Wall (TDW) provides a cost-effective way to create an extremely high resolution display, capable of approaching the image sizes now gen- erated by modern astronomical instruments. Astronomers face the challenge of inspecting single large images, many similar images simultaneously, and heterogeneous but related content. Many research institutions have constructed TDWs on the basis that they will improve the scientific outcomes of astronomical imagery. We test this concept by presenting sample images to astronomers and non- astronomers using a standard desktop display (SDD) and a TDW. These samples include standard English words, wide field galaxy surveys and nebulae mosaics from the Hubble telescope. These experiments show that TDWs provide a better environment for searching for small targets in large images than SDDs. It also shows that astronomers tend to be better at searching images for targets than non-astronomers, both groups are generally better when employing physical navigation as opposed to virtual navigation, and that the combination of two non-astronomers using a TDW rivals the experience of a single astronomer. However, there is also a large distribution in aptitude amongst the participants and the nature of the content also plays a significant role is success.Comment: 19 pages, 15 figures, accepted for publication in PASA (Publications of the Astronomical Society of Australia

The Process of Schema Emergence: Assimilation, Deconstruction, Unitization and the Plurality of Analogies

Schemas are a central concept in strategy and organization theory. Yet, despite the importance of schemas, little is known about how they emerge. Our in-depth historical analysis of how groups in the life insurance industry developed their schema for the computer from 1945-1975 addresses this gap. We identify three key processes— assimilation, deconstruction, and unitization—that collectively explain and resolve an inherent tension related to schema emergence: how to make the unfamiliar familiar but conceptually distinct. We also find that each process relates to analogical transfer, but in a more pluralistic and dynamic way than the existing literature describes. Broadly, these findings have important implications for rganizational change and managerial cognition

Ventricular Tachycardia in the Absence of Structural Heart Disease

In up to 10% of patients who present with ventricular tachycardia (VT), obvious structural heart disease is not identified. In such patients, causes of ventricular arrhythmia include right ventricular outflow tract (RVOT) VT, extrasystoles, idiopathic left ventricular tachycardia (ILVT), idiopathic propranolol-sensitive VT (IPVT), catecholaminergic polymorphic VT (CPVT), Brugada syndrome, and long QT syndrome (LQTS). RVOT VT, ILVT, and IPVT are referred to as idiopathic VT and generally do not have a familial basis. RVOT VT and ILVT are monomorphic, whereas IPVT may be monomorphic or polymorphic. The idiopathic VTs are classified by the ventricle of origin, the response to pharmacologic agents, catecholamine dependence, and the specific morphologic features of the arrhythmia. CPVT, Brugada syndrome, and LQTS are inherited ion channelopathies. CPVT may present as bidirectional VT, polymorphic VT, or catecholaminergic ventricular fibrillation. Syncope and sudden death in Brugada syndrome are usually due to polymorphic VT. The characteristic arrhythmia of LQTS is torsades de pointes. Overall, patients with idiopathic VT have a better prognosis than do patients with ventricular arrhythmias and structural heart disease. Initial treatment approach is pharmacologic and radiofrequency ablation is curative in most patients. However, radiofrequency ablation is not useful in the management of inherited ion channelopathies. Prognosis for patients with VT secondary to ion channelopathies is variable. High-risk patients (recurrent syncope and sudden cardiac death survivors) with inherited ion channelopathies benefit from implantable cardioverter-defibrillator placement. This paper reviews the mechanism, clinical presentation, and management of VT in the absence of structural heart disease

Investigation of water vapor motion winds from geostationary satellites

Water vapor imagery from geostationary satellites has been available for over a decade. These data are used extensively by operational analysts and forecasters, mainly in a qualitative mode (Weldon and Holmes 1991). In addition to qualitative applications, motions deduced in animated water vapor imagery can be used to infer wind fields in cloudless regimes, thereby augmenting the information provided by cloud-drift wind vectors. Early attempts at quantifying the data by tracking features in water vapor imagery met with modest success (Stewart et al. 1985; Hayden and Stewart 1987). More recently, automated techniques have been developed and refined, and have resulted in upper-level wind observations comparable in quality to current operational cloud-tracked winds (Laurent 1993). In a recent study by Velden et al. (1993) it was demonstrated that wind sets derived from Meteosat-3 (M-3) water vapor imagery can provide important environmental wind information in data void areas surrounding tropical cyclones, and can positively impact objective track forecasts. M-3 was repositioned to 75W by the European Space Agency in 1992 in order to provide complete coverage of the Atlantic Ocean. Data from this satellite are being transmitted to the U.S. for operational use. Compared with the current GOES-7 (G-7) satellite (positioned near 112W), the M-3 water vapor channel contains a superior horizontal resolution (5 km vs. 16 km ). In this paper, we examine wind sets derived using automated procedures from both GOES-7 and Meteosat-3 full disk water vapor imagery in order to assess this data as a potentially important source of large-scale wind information. As part of a product demonstration wind sets were produced twice a day at CIMSS during a six-week period in March and April (1994). These data sets are assessed in terms of geographic coverage, statistical accuracy, and meteorological impact through preliminary results of numerical model forecast studies

Will Small-Scale Dairy Producers in Kenya Disappear Due to Economies of Scale in Production?

There is growing policy concern regarding the competitiveness of small-scale livestock production in the wake of the contemporary livestock revolution in many developing countries. In Kenya, this debate has focused on economies of scale and the undue influence of policy distortions on promoting the scaling up of dairy farms. This paper seeks to investigate economies of scale in Kenyan dairy in terms of relative profit efficiency at different levels of output, and identify policy and technology options to help small-scale farmers develop solutions to the challenges of competition. Data were collected from 204 dairy producers of different farm sizes in rural Kiambu and Thika, and urban Nairobi districts and a stochastic frontier model approach was used to analyze the determinants of profitability and inefficiency. Unit profitability per farm ranged between US$0.13 - US$0.16 per liter of milk with no significant variation across scales of farm. However, at all given levels of scale of farm, inefficiency significantly contributed to variability in profitability across farms. Scale had no significant effect on efficiency, confirming the relative competitiveness of small-scale dairy producers. Dairy farmers with commercial poultry achieved higher relative profit efficiency as poultry waste was fed to cattle. Rural location relative to Nairobi also increased efficiency. Linking rural areas and major market centre with good roads, strengthening of farmers' co-operative societies and exploring use of cheaper raw materials in the manufacture of concentrate feeds may strengthen the competitive position small dairy farms versus large ones.Dairy Production, Stochastic Production Frontier, Efficiency, Profitability, Livestock Production/Industries, C21, Q12,