Home About us Contact
|
Home About us Contact | ||
|
|
||
Desired Effect (desired + effect)
Selected AbstractsFrom dynamic influence nets to dynamic Bayesian networks: A transformation algorithmINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 8 2009Sajjad Haider This paper presents an algorithm to transform a dynamic influence net (DIN) into a dynamic Bayesian network (DBN). The transformation aims to bring the best of both probabilistic reasoning paradigms. The advantages of DINs lie in their ability to represent causal and time-varying information in a compact and easy-to-understand manner. They facilitate a system modeler in connecting a set of desired effects and a set of actionable events through a series of dynamically changing cause and effect relationships. The resultant probabilistic model is then used to analyze different courses of action in terms of their effectiveness to achieve the desired effect(s). The major drawback of DINs is their inability to incorporate evidence that arrive during the execution of a course of action (COA). Several belief-updating algorithms, on the other hand, have been developed for DBNs that enable a system modeler to insert evidence in dynamic probabilistic models. Dynamic Bayesian networks, however, suffer from the intractability of knowledge acquisition. The presented transformation algorithm combines the advantages of both DINs and DBNs. It enables a system analyst to capture a complex situation using a DIN and pick the best (or close-to-best) COA that maximizes the likelihood of achieving the desired effect. During the execution, if evidence becomes available, the DIN is converted into an equivalent DBN and beliefs of other nodes in the network are updated. If required, the selected COA can be revised on the basis of the recently received evidence. The presented methodology is applicable in domains requiring strategic level decision making in highly complex situations, such as war games, real-time strategy video games, and business simulation games. © 2009 Wiley Periodicals, Inc. [source] Training physicians to increase patient trustJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 3 2000David H. Thom MD PhD Abstract Patient trust in the physician is an important aspect of the patient,physician relationship that has recently become a focus of interest, in part due to the rise of managed care in the US healthcare system. In a previous study, we identified physician behaviours reported by patients as important to establishing their trust in the physician. The current study attempted to modify these behaviours via a short training programme and thereby to increase patient trust and improve associated outcomes. After baseline measurements, 10 physicians were randomized to the intervention group and 10 remained as a control group. While intervention physicians showed a net improvement in 16 of 19 specific patient-reported behaviours when compared to control physicians, these differences were not statistically significant. There was also no significant difference in patient trust, patient satisfaction, continuity, self-reported adherence, number of referrals or number of diagnostic tests ordered. This short training course in a group of self-selected physicians was not a sufficiently strong intervention to achieve the desired effect. Suggestions are given for designing a stronger training intervention. [source] Percutaneous Mitral Valve Repair for Mitral RegurgitationJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2003PETER C. BLOCK M.D. Mitral regurgitation (MR) associated with, ischemic, and degenerative (prolapse) disease, contributes to left ventricular (LV) dysfunction due to remodeling, and LV dilation, resulting in worsening of MR. Mitral valve (MV) surgical repair has provided improvement in survival, LV function and symptoms, especially when performed early. Surgical repair is complex, due to diverse etiologies and has significant complications. The Society for Thoracic Surgery database shows that operative mortality for a 1st repair is 2% and for re-do repair is 4 times that. Cardiopulmonary bypass and cardiac arrest are required. The attendant morbidity prolongs hospitalization and recovery. Alfieri simplified mitral repair using an edge-to-edge technique which subsequently has been shown to be effective for multiple etiologies of MR. The MV leaflers are typically brought together by a central suture producing a double orifice MV without stenosis. Umana reported that MR decreased from grade 3.6 +/,0.5 to0.8 +/,0.4 (P < 0.0001)and LV ejection fraction increased from 33 +/,13% to 45 +/,11%(P = 0.0156). In 121 patients, Maisano reported freedom from re-operation of 95 +/,4.8% with up to 6 year follow-up. Oz developed a MV "grasper" that is directly placed via a left ventriculotomy and coapts both leaflets which are then fastened by a graduated spiral screw. An in-vitro model using explanted human valves showed significant reduction in MR and in canine studies, animals followed by serial echo had persistent MV coaptation. At 12 weeks the device was endothelialized. These promising results have paved the way for a percutaneous or minimally invasive off pump mitral repair. Evalve has developed catheter-based technology, which, by apposing the edges of a regurgitant MV, results in edge-to-edge repair. Release of the device is done after echo and fluoroscopic evaluation under normal loading conditions. If the desired effect is not produced the device can be repositioned or retrieved. Animal studies show excellent healing, with incorporation of the device into the leaflets at 6,10 weeks with persistent coaptation. Another percutaneous approach has been to utilize the proximity of the coronary sinus (CS) to the mitral annulus (MA). Placement of a self-compressing device in the CS along the region of the posterior MA has, in canine models, reduced MR and addresses the issues of MA dilation and its contribution to MR. Ongoing studies are underway for both techniques. (J Interven Cardiol 2003;16:93,96) [source] Large subunit rDNA and rbcL gene sequence data place Petrohua bernabei gen. et sp. nov. in the Batrachospermales (Rhodophyta), but do not provide further resolution among taxa in this orderPHYCOLOGICAL RESEARCH, Issue 2 2007Morgan L. Vis SUMMARY The phylogenetic relationship among 12 previously described batrachospermalean taxa and a novel member of the order were investigated using the LSU and rbcL genes separately and in combination. The primary goal of this research was to establish the phylogenetic placement of a previously undescribed freshwater red alga from Chile. The results showed that the new entity with pseudoparenchymatous tube morphology is a member of the Batrachospermales and Petrohua bernabei gen. et sp. nov. is described herein. This is the first record to our knowledge of a Lemanea -like alga from Chile. It would appear that this thallus construction has evolved at least three times in the Batrachospermales and that the switch from a Batrachospermum -like construction to a pseudoparenchymatous construction may be a repeated adaptive response to turbulent waterfall habitats. In addition to providing information about a new freshwater red alga, this study sought to determine whether combining the data from two genes would produce a more robust phylogeny, particularly for intermediate nodes, to resolve familial relationships within the order. As with previous analyses, the Batrachospermales was resolved as a clade and support was high for relationships resolved among relatively recent nodes. Unfortunately, combining the LSU and rbcL data did not have the desired effect of more fully resolving intermediate nodes among the Batrachospermales. [source] Aberration controll with contact lensesACTA OPHTHALMOLOGICA, Issue 2007A LINDSKOOG PETTERSSON Purpose: To investigate and compare the reduction in ocular aberrations with standard hydrogel contact lenses (i.e., lenses not designed to control aberrations) and with aberration controlled hydrogel and silicon-hydrogel contact lenses. Methods: The aberrations with and without contact lenses were measured in 42 subjects between 20 and 37 years of age using a Zywave wave front sensor (B&L). 22 subjects were fitted a standard contact lens and an aberration controlled hydrogel lens. The remaining 20 subjects were fitted aberration controlled silicon-hydrogel lenses Results: With the standard lens the aberrations were controlled (i.e., close to zero) with a 4.0 mm pupil. Whereas, with both the aberration control lenses the residual spherical aberrations became negative. The reduction in aberrations differed significantly (p<0.05) between all lenses. Conclusions: Since aberration controlled contact lenses in many subjects overcorrect the spherical aberrations when the pupil size is normal (~4.0 mm) we suggest measuring wave front aberrations in each patient both with and without contact lenses in order to achieve the desired effect. [source] | ||||||||||