Mean increases in bone mineral density at each skeletal site were greatest for men
with the highest levels of serum C-telopeptide and tartrate-resistant alkaline phosphatase 5b.
Conclusions: Denosumab significantly and consistently increased bone mineral density at all skeletal sites and in every subgroup, including men at greatest risk for bone loss and fractures.”
“What biological mechanisms underlie the reward-predictive firing properties of midbrain dopaminergic neurons, and how do they relate to the complex constellation of empirical findings understood as Pavlovian and instrumental conditioning? We previously presented PVLV, a biologically inspired Pavlovian learning algorithm accounting for DA activity in terms of two interrelated systems: a primary value (PV) system, which governs how DA cells respond to a US (reward) and; a learned click here value (LV) system, which governs how DA cells respond to a CS. Here, we provide a more extensive review of the biological mechanisms supporting phasic DA firing and their relation to the spate of Pavlovian conditioning phenomena and their sensitivity to focal brain lesions. We further extend the model by incorporating a new NV (novelty JNK-IN-8 concentration value) component reflecting the ability of novel stimuli
to trigger phasic DA firing, providing “”novelty bonuses”" which encourages exploratory working memory updating and in turn speeds learning Selleck MX69 in trace conditioning and other working memory-dependent paradigms. The
evolving PVLV model builds upon insights developed in many earlier computational models, especially reinforcement learning models based on the ideas of Sutton and Barto, biological models, and the psychological model developed by Savastano and Miller. The PVLV framework synthesizes these various approaches, overcoming important shortcomings of each by providing a coherent and specific mapping to much of the relevant empirical data at both the micro- and macro-levels, and examines their relevance for higher order cognitive functions. (C) 2009 Elsevier Ltd. All rights reserved.”
“Purpose: It has been clearly demonstrated that surgeons with increased yearly caseloads have lower complication rates. Moreover it has been shown that a surgeon needs to conduct at least 250 radical prostatectomies to maximize cancer control (the surgical learning curve).
Materials and Methods: To determine typical annual radical prostatectomy caseloads of surgeons in the United States we analyzed data from 2 independent data sets for 2005, that of a nationally representative sample (Nationwide Inpatient Sample) and a complete record of all hospital discharges from New York State (Statewide Planning and Research Cooperative System).