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The article focuses on pulsed-field ablation (PFA) as a method of non-thermal ablation for cardiac arrhythmias. It discusses the role of contact force in lesion formation during PFA and suggests that even minimal contact force may be sufficient to create transmural lesions, potentially improving the safety and efficacy of the procedure.

Introduction: The VICTORY AF Study was designed to evaluate the risk of the procedure and/or device‐related strokes in patients with PersAF on warfarin undergoing ablation with a phased radiofrequency (RF) system. Methods: The VICTORY AF trial was a prospective, multicenter, single‐arm, investigational study. PersAF patients on vitamin K antagonism without major structural heart disease or history of stroke/transient ischemic attack undergoing phased RF ablation for atrial fibrillation (AF) were included. The primary outcome was the incidence of the procedure and/or device‐related stroke within 30 days of the ablation by a board‐certified neurologist's assessment. The secondary outcomes were an acute procedural success, 6 months effectiveness (defined as the reduction in AF/atrial flutter episodes lasting ≥10 minutes by 48‐hour Holter 6 months postablation) and the number of patients with pulmonary vein (PV) stenosis. Results: A total of 129 (108 PersAF, 21 long‐standing PersAF) patients were treated (mean age: 60.6 ± 7.7; 79.8% male, 54.3% CHA2Ds2‐VASc score ≥ 2). Two nondisabling strokes were reported (1.6%); one before discharge and the second diagnosed at the 30‐day visit. Due to slow enrollment, the study was terminated before reaching the 95% one‐sided upper confidence boundary for stroke incidence. Acute procedural success was 93.8%, and at 6 months, 72.8% of patients demonstrated ≥90% reduction in AF burden, 78.9% were off all antiarrhythmic drugs. There were no patients with PV stenosis of greater than 70%. Conclusions: VICTORY AF demonstrated a 1.6% incidence of stroke in PersAF undergoing ablation with a phased RF system which did not meet statistical confidence due to poor enrollment. The secondary outcomes suggest comparable efficacy to phased RF in the tailored treatment of permanent AF trial. Rigorous clinical evaluation of the stroke risk of new AF ablation technologies as well as restriction to Vitamin K antagonist anticoagulation appears to be unachievable goals in a clinical multicenter IDE trial of AF ablation in the current era. [ABSTRACT FROM AUTHOR]

We investigated whether and how emotional information would affect analogical reasoning. We hypothesized that task-irrelevant emotional information would impair performance whereas task-relevant emotional information would enhance it. In Study 1, 233 undergraduates completed a novel version of the People Pieces Task (Emotional Faces People Task), an analogical reasoning task in which the task characters displayed emotional or neutral facial expressions (within-participants). The emotional faces were relevant or irrelevant to the task (between-participants). We simulated the behavioral results using the Learning and Inference with Schemas and Analogies (LISA) model of relational reasoning. LISA is a neurally plausible, symbolic-connectionist computational model of analogical reasoning. In comparison to neutral trials, participants were slower but more accurate on emotion-relevant trials, and were faster but less accurate on emotion-irrelevant trials. Simulations using the LISA model demonstrated that it is possible to account for the effects of emotional information on reasoning in terms of how emotional stimuli attract attention during a reasoning task. In Study 2, 255 undergraduates completed the Emotional Faces People Task at either a high- or low-working memory load. The high working memory load condition of Study 2 replicated the findings of Study 1, showing that participants were more accurate on emotion-relevant trials than on emotion-irrelevant trials; in Study 2, this increased accuracy could not be accounted for by a speed-accuracy tradeoff. The working memory manipulation influenced the manner in which the congruence (with the correct answer) of emotion-irrelevant emotion influenced performance. Simulations using the LISA model showed that manipulating the salience of emotion, the error penalty, as well as vigilance (which determines the likelihood that LISA will notice it has attended to an irrelevant relation), could reasonably reproduce the behavioral results of both low and high working memory load conditions of Study 2. [ABSTRACT FROM AUTHOR]

Fluorescence and photoacoustic imaging techniques offer valuable insights into cell- and tissue-level processes. However, these optical imaging modalities are limited by scattering and absorption in tissue, resulting in the low-depth penetration of imaging. Contrast-enhanced imaging in the near-infrared window improves imaging penetration by taking advantage of reduced autofluorescence and scattering effects. Current contrast agents for fluorescence and photoacoustic imaging face several limitations from photostability and targeting specificity, highlighting the need for a novel imaging probe development. This review covers a broad range of near-infrared fluorescent and photoacoustic contrast agents, including organic dyes, polymers, and metallic nanostructures, focusing on their optical properties and applications in cellular and animal imaging. Similarly, we explore encapsulation and functionalization technologies toward building targeted, nanoscale imaging probes. Bioimaging applications such as angiography, tumor imaging, and the tracking of specific cell types are discussed. This review sheds light on recent advancements in fluorescent and photoacoustic nanoprobes in the near-infrared window. It serves as a valuable resource for researchers working in fields of biomedical imaging and nanotechnology, facilitating the development of innovative nanoprobes for improved diagnostic approaches in preclinical healthcare. [ABSTRACT FROM AUTHOR]

The merits of distributed representations are widely discussed but, I believe, largely misunderstood. My purpose in this paper is to put the issue of distributed representations into context. I will argue that the termdistributedis only meaningful with respect to that which is being represented and that degree to which a localist or a distributed code is more desirable depends on the goals of the computation to be performed. I will also argue that localist codes play an essential role in symbolic neural computation. [ABSTRACT FROM PUBLISHER]

Background Left ventricular lead (LVL) implant success rates have historically ranged between 70.5% and 95.5%. To date, there are few large studies that evaluate LVL implant success utilizing a single family of delivery catheters and leads. The Attain Success study was a prospective nonrandomized multicenter global study with the main objectives of assessing single-system LVL implant success and complication rates. Methods Patients undergoing cardiac resynchronization therapy implantation were eligible for enrollment. There was no prespecified level of experience for investigator participation. LVL implant success and complication rates were assessed though 3 months of follow-up. Results A total of 2,014 patients (69.1 ± 12.0 years, 71% male and 38% atrial fibrillation) were enrolled from 114 centers with a follow-up of 3.5 ± 2.1 months. Coronary sinus cannulation success rate was 96.4% with Attain Family delivery catheters. Implant success rate for Attain Family leads using Attain Family catheters was 94.0%; overall LVL implant success rate was 97.1%. Median procedure time was 4 minutes for cannulation and 9 minutes for LVL placement. Median fluoroscopy time was 17 minutes and median contrast used was 25 cc. There were 55 catheter or LVL-related complications in 53 subjects; the majority were LVL dislodgements (34, 1.7%) and extracardiac stimulation (11, 0.5%). The Kaplan-Meier estimate of the 3-month complication probability was 2.6%. Conclusion This study represents the largest prospective evaluation of LVL implantation to date, revealing a high LVL implant success rate and low complication rate using a single family of leads and delivery catheters. [ABSTRACT FROM AUTHOR]

Theories of relational concept acquisition (e.g., schema induction) based on structured intersection discovery predict that relational concepts with a probabilistic (i.e., family resemblance) structure ought to be extremely difficult to learn. We report four experiments testing this prediction by investigating conditions hypothesized to facilitate the learning of such categories. Experiment 1 showed that changing the task from a category-learning task to choosing the 'winning' object in each stimulus greatly facilitated participants' ability to learn probabilistic relational categories. Experiments 2 and 3 further investigated the mechanisms underlying this 'who's winning' effect. Experiment 4 replicated and generalized the 'who's winning' effect with more natural stimuli. Together, our findings suggest that people learn relational concepts by a process of intersection discovery akin to schema induction, and that any task that encourages people to discover a higher order relation that remains invariant over members of a category will facilitate the learning of putatively probabilistic relational concepts. [ABSTRACT FROM AUTHOR]

Across many areas of study in cognition, the capacity of working memory (WM) is widely agreed to be roughly three to five items: three to five objects (i.e., bound collections of object features) in the literature on visual WM or three to five role bindings (i.e., objects in specific relational roles) in the literature on memory and reasoning. Three experiments investigated the capacity of observers' WM for the spatial relations among objects in a visual display, and the results suggest that the 'items' in WM are neither simply objects nor simply role bindings. The results of Experiment 1 are most consistent with a model that treats an 'item' in visual WM as an object, along with the roles of all its relations to one other object. Experiment 2 compared observers' WM for object size with their memory for relative size and provided evidence that observers compute and store objects' relations per se (rather than just absolute size) in WM. Experiment 3 tested and confirmed several more nuanced predictions of the model supported by Experiment 1. Together, these findings suggest that objects are stored in visual WM in pairs (along with all the relations between the objects in a pair) and that, from the perspective of WM, a given object in one pair is not the same 'item' as that same object in a different pair. [ABSTRACT FROM AUTHOR]

Relational concepts play a central role in human perception and cognition, but little is known about how they are acquired. For example, how do we come to understand that physical force is a higher-order multiplicative relation between mass and acceleration, or that two circles are the same-shape in the same way that two squares are? A recent model of relational learning, DORA (Discovery of Relations by Analogy; Doumas, Hummel & Sandhofer, 2008), predicts that comparison and analogical mapping play a central role in the discovery and predication of novel higher-order relations. We report two experiments testing and confirming this prediction. [ABSTRACT FROM AUTHOR]

Over the last 20 years, international development agencies like SNV Netherlands Development Organisation have hesitantly become involved in tourism. This paper explains the complex and rarely researched political and technical issues behind the working practices, drivers and beliefs of an aid agency seeking to alleviate poverty via tourism development. Based on insiders’ commentaries and documentary sources, it presents five phases of the conceptual and material ordering of tourism within SNV. The phases took SNV from opposition to tourism work, through Community-Based Tourism (CBT), expansion, links to Millennium Development Goals, working in partnership with the private sector and an overall increasing need to deliver defined short term results – to closure. It explains how and why tourism became an important part of development work and how changing policy discourses and practices of international and national organisations influence the way tourism is practised as part of development work. It shows that SNV itself stimulated strong international debates about tourism and development. It concludes that relations between tourism and development remain highly contested and require the continual production of “success”. SNV is now gradually closing its poverty reduction through tourism work. The paper reflects on lessons that might be learned from the SNV story. [ABSTRACT FROM PUBLISHER]

Abecassis, Sera, Yonas, and Schwade (2001) showed that young children represent shapes more metrically, and perhaps more holistically, than do older children and adults. How does a child transition from representing objects and events as undifferentiated wholes to representing them explicitly in terms of their attributes? According to RBC (Recognition-by-Components theory; Biederman, 1987 ), objects are represented as collections of categorical geometric parts (“geons”) in particular categorical spatial relations. We propose that the transition from holistic to more categorical visual shape processing is a function of the development of geon-like representations via a process of progressive intersection discovery. We present an account of this transition in terms of DORA ( Doumas, Hummel, & Sandhofer, 2008 ), a model of the discovery of relational concepts. We demonstrate that DORA can learn representations of single geons by comparing objects composed of multiple geons. In addition, as DORA is learning it follows the same performance trajectory as children, originally generalizing shape more metrically/holistically and eventually generalizing categorically. [ABSTRACT FROM AUTHOR]

Abstract: Similarity plays a central role in the study of perception and cognition. Previous attempts to model similarity have captured effects of either featural or structural similarity, but typically not both. We simulated both by fitting similarity data with the LISA model of relational reasoning [Hummel, J. E., & Holyoak, K. J. (1997). Distributed representations of structure: A theory of analogical access and mapping. Psychological Review, 104, 427–466, Hummel, J. E., & Holyoak, K. J. (2003a). A symbolic-connectionist theory of relational inference and generalization. Psychological Review, 110, 220–264]. The same mechanisms LISA uses to simulate analogy also provide a natural account of feature-based similarity effects (e.g., violations of symmetry), structural effects (e.g., the advantage of alignable over non-alignable differences), and the combined effects of featural and structured information (i.e., MIPs and MOPs; “Matches In/Out of Place”) on similarity judgments. Our approach differs from most models of similarity in that LISA was not originally designed to simulate similarity judgments, but rather analogical reasoning. LISA’s incidental ability to simulate diverse similarity effects speaks to the plausibility of the model’s account of human knowledge representation. [Copyright &y& Elsevier]

Automated sensing of soil macronutrients would be useful in mapping soil nutrient variability for variable-rate nutrient management. Ion-selective electrodes (ISEs) are a promising approach because of their small size, rapid response, and ability to directly measure the analyte. This study reports on the laboratory evaluation of a sensor array including three different ISEs, based on TDDA-NPOE and valinomycin-DOS membranes, and Co rod, for the simultaneous determination of NO3-N, available K, and available P in soil extracts. Thirty-seven Illinois and Missouri soils were extracted using the Kelowna soil extractant (0.25 mol L-1 CH3COOH + 0.015 mol L-1 NH4F). The response of each electrode type in mixed solutions of NO3, K, and P ions was modeled based on the Nikolskii-Eisenman equation with all coefficients of determination (r²) ≥0.95 (P < 0.001). In soil extracts, the NO3 ISEs provided concentrations similar to those obtained with standard laboratory methods (r² = 0.89, P < 0.00 1). Concentrations obtained with the K ISEs were about 50% lower than those obtained with standard methods due to lower K extraction by the Kelowna solution (r² = 0.85, P < 0.001). The P ISEs provided concentrations about 64% lower than those obtained with standard methods due to a combination of decreased P estimates in soil extracts and lower P extraction by the Kelowna solution; however, there was a strong linear relationship (r² = 0.81, P< 0.001). Although P and K concentrations were low in comparison to standard laboratory procedures, a calibration Factor could address this issue. These results show that ISE technology can be implemented successfully for NO3-N, available K, and available P measurement with the Kelowna extracrant. [ABSTRACT FROM AUTHOR]

Identification of objects in a scene may be influenced by functional relations among those objects. In this study, observers indicated whether a target object matched a label. Each target was presented with a distractor object, and these were sometimes arranged to interact (as if being used together) and sometimes not to interact. When the distractor was semantically related to the label, identification was more accurate for targets arranged to interact with that distractor. This effect depended on observers' ability to perceptually integrate the stimulus objects, suggesting that it was perceptual in nature. The effect was not attributable to attentional cuing and did not depend on expectation of certain object pairs. These data suggest that familiar functional groupings of objects are perceptually grouped. [ABSTRACT FROM AUTHOR]

Previous research has shown that synchronized flicker can facilitate detection of a single Kanizsa square. The present study investigated the role of temporally structured priming in discrimination tasks involving perceptual relations between multiple Kanizsa-type figures. Results indicate that visual information presented as temporally structured flicker in the gamma band can modulate the perception of multiple objects in a subsequent display. For judgments of both relative orientation and relative position of 2 rectangles, response time to identify and discriminate relations between the objects was consistently decreased when the vertices corresponding to distinct Kanizsa-type rectangles were primed asynchronously. Implications are discussed for models of the perception of objects and their interrelations. [ABSTRACT FROM AUTHOR]

Human mental representations are both flexible and structured—properties that, together, present challenging design requirements for a model of human thinking. The Learning and Inference with Schemas and Analogies (LISA) model of analogical reasoning aims to achieve these properties within a neural network. The model represents both relations and objects as patterns of activation distributed over semantic units, integrating these representations into propositional structures using synchrony of firing. The resulting propositional structures serve as a natural basis for memory retrieval, analogical mapping, analogical inference, and schema induction. The model also provides an a priori account of the limitations of human working memory and can simulate the effects of various kinds of brain damage on thinking. [ABSTRACT FROM AUTHOR]

Extant theories of decoy effects on evaluations of attribute values were assessed with respect to their ability to account for a one-dimensional analogue of the asymmetric dominance effect. Parducci's (1965, 1995) range-frequency theory, Krumhansl's (1978) distance-density model, Tversky's (1977) diagnosticity principle, and reference point theories (e.g., Holyoak & Mah, 1982) were unable to account for this effect. One version of Helson's (1964) adaptation-level theory and our comparison-induced distortion theory (Choplin & Hummel, 2002) were able to account for the qualitative effect. Quantitative fits revealed that comparison-induced distortion theory provides a better account of this effect than does adaptation-level theory. These results suggest that, in some cases, biases created by language-expressible magnitude comparisons mediate the effects of decoys on evaluation. [ABSTRACT FROM AUTHOR]

According to the hybrid theory of object recognition (J. E. Hummel, 2001), ignored object images are represented holistically, and attended images are represented both holistically and analytically. This account correctly predicts patterns of visual priming as a function of translation, scale (B. J. Stankiewicz & J. E. Hunmmel, 2002), and left-right reflection (B. J. Stankiewicz, J. E. Hummel, & E. E. Cooper, 1998). The model also predicts that priming for attended images will generalize over configural distortions (split images), whereas priming for ignored images will not. Three experiments tested and confirmed this prediction. Split images visually primed their intact and split counterparts when they were attended but not when they were ignored, whereas intact images primed themselves whether they were attended or not. The data contribute to the growing body of evidence that 1 function of visual attention is to permit the generation of explicitly relational representations of object shape. [ABSTRACT FROM AUTHOR]

: ObjectivesThis study was conducted to assess the safety and effectiveness of cardiac resynchronization therapy (CRT) when combined with an implantable cardioverter defibrillator (ICD).: BackgroundLong-term outcome of CRT was measured in patients with symptomatic heart failure (HF), intraventricular conduction delay, and malignant ventricular tachyarrhythmias (ventricular tachycardia/ventricular fibrillation [VT/VF]) requiring therapy from an ICD.: MethodsPatients (n = 490) were implanted with a device capable of providing both CRT and ICD therapy and randomized to CRT (n = 245) or control (no CRT, n = 245) for up to six months. The primary end point was progression of HF, defined as all-cause mortality, hospitalization for HF, and VT/VF requiring device intervention. Secondary end points included peak oxygen consumption (VO2), 6-min walk (6 MW), New York Heart Association (NYHA) class, quality of life (QOL), and echocardiographic analysis.: ResultsA 15% reduction in HF progression was observed, but this was statistically insignificant (p = 0.35). The CRT, however, significantly improved peak VO2 (0.8 ml/kg/min vs. 0.0 ml/kg/min, p = 0.030) and 6 MW (35 m vs. 15 m, p = 0.043). Changes in NYHA class (p = 0.10) and QOL (p = 0.40) were not statistically significant. The CRT demonstrated significant reductions in ventricular dimensions (left ventricular internal diameter in diastole = −3.4 mm vs. −0.3 mm, p < 0.001 and left ventricular internal diameter in systole = −4.0 mm vs. −0.7 mm, p < 0.001) and improvement in left ventricular ejection fraction (5.1% vs. 2.8%, p = 0.020). A subgroup of patients with advanced HF (NYHA class III/IV) consistently demonstrated improvement across all functional status end points.: ConclusionsThe CRT improved functional status in patients indicated for an ICD who also have symptomatic HF and intraventricular conduction delay. [Copyright &y& Elsevier]

: ObjectivesThe purpose of this multicenter randomized trial was to compare total mortality during therapy with amiodarone or an implantable cardioverter-defibrillator (ICD) in patients with nonischemic dilated cardiomyopathy (NIDCM) and nonsustained ventricular tachycardia (NSVT).: BackgroundWhether an ICD reduces mortality more than amiodarone in patients with NIDCM and NSVT is unknown.: MethodsOne hundred three patients with NIDCM, left ventricular ejection fraction ≤0.35, and asymptomatic NSVT were randomized to receive either amiodarone or an ICD. The primary end point was total mortality. Secondary end points included arrhythmia-free survival, quality of life, and costs.: ResultsThe study was stopped when the prospective stopping rule for futility was reached. The percent of patients surviving at one year (90% vs. 96%) and three years (88% vs. 87%) in the amiodarone and ICD groups, respectively, were not statistically different (p = 0.8). Quality of life was also similar with each therapy (p = NS). There was a trend with amiodarone, as compared to the ICD, towards improved arrhythmia-free survival (p = 0.1) and lower costs during the first year of therapy ($8,879 vs. $22,039, p = 0.1).: ConclusionsMortality and quality of life in patients with NIDCM and NSVT treated with amiodarone or an ICD are not statistically different. There is a trend towards a more beneficial cost profile and improved arrhythmia-free survival with amiodarone therapy. [Copyright &y& Elsevier]

The authors present a theory of how relational inference and generalization can be accomplished within a cognitive architecture that is psychologically and neurally realistic. Their proposal is a form of symbolic connectionism: a connectionist system based on distributed representations of concept meanings, using temporal synchrony to bind fillers and roles into relational structures. The authors present a specific instantiation of their theory in the form of a computer simulation model, Learning and Inference with Schemas and Analogies (LISA). By using a kind of self-supervised learning, LISA can make specific inferences and form new relational generalizations and can hence acquire new schemas by induction from examples. The authors demonstrate the sufficiency of the model by using it to simulate a body of empirical phenomena concerning analogical inference and relational generalization. [ABSTRACT FROM AUTHOR]

Attended objects visually prime both themselves and their left–right reflections, whereas ignored objects prime themselves but not their left–right reflections (Stankiewicz, Hummel, & Cooper, 1998). Two experiments extended this research by investigating the role of attention in priming across changes in size and location in the visual field. Experiment 1 showed that visual priming for both attended and ignored images is invariant with translation across the visual field. Experiment 2 showed that visual priming for both attended and ignored images is invariant with scale. In combination with the findings of Stankiewicz et al., these findings support the hypothesis that object recognition is based on a hybrid representation of shape. [ABSTRACT FROM AUTHOR]

Focuses on the importance of various cognitive processes to the mental representation of magnitude. Effect of asymmetric dominance on decision-making literature; Initial assessment of magnitude; Determination of the value of magnitude.

Behavioural, neural, and computational considerations suggest that the visual system may use (at least) two approaches to binding an object's features and/or parts into a coherent representation of shape: Dynamically bound (e.g., by synchrony of firing) representations of part attributes and spatial relations form a structural description of an object's shape, while units representing shape attributes at specific locations (i.e., a static binding of attributes to locations) form an analogue (image-like) representation of that shape. I will present a computational model of object recognition based on this proposal and empirical tests of the model. The model accounts for a large body of findings in human object recognition, and makes several novel and counter intuitive predictions. In brief, it predicts that visual priming for attended objects will be invariant with translation, scale, and left–right reflection, whereas priming for unattended objects will be invariant with translation and scale, but sensitive to left–right reflection. Five experiments demonstrated the predicted relationships between visual attention and patterns of visual priming as a function of variations in viewpoint. The implications of these findings for theories of visual binding and shape perception will be discussed. [ABSTRACT FROM AUTHOR]

Examines the impact of perceptual properties on the effectiveness of diagrams in analogical problem solving. Use of convergence diagrams as source analogue for the radiation problem; Role of a verbal statement in the accessibility of a static diagram; Influence of animation in analogical transfer.

Investigates the role of connectedness in the use of part-relation conjunctions for shape category learning. Variations of topological relationship between the parts of learning shapes; Increase of speed and accuracy of category learning when an object's parts were connected than when an object is separated; Influence of connectedness on the integration of parts with their relations.

Investigates potential perceptual constraint on property interactions in object category learning. Question of the existence of a perceptual constraint that makes part-location conjunctions particularly salient in object category learning.

Examines the role of visual attention in priming for object images and their left-right reflections relating to dual representation of object shape and visual perception. Information on the effect of attention; What results suggested; Details on visual priming and invariance with left-right reflection; Effect of attended images on their left-right reflections; Role of attention in visual perception.

Provides information on a study of seven experiments investigating whether part connectedness would facilitate the perception of spatial relations among object parts. Detailed information on the effects of connectedness in temporal visual search; Methodology used to conduct the experiments; Results of the experiments; Discussion on the results.

A striking aspect of the human capacity for object recognition is that it is largely unaffected by where the object's image falls on the retina, the size of the image, or the orientation in depth from which the object is viewed. A fundamental challenge for theories of human object recognition is to explain how to achieve this invariance with viewpoint. In this article, the author reviews four general approaches to this problem in the computational modeling literature and discuss evidence bearing on each as an account of human object recognition. Some of the earliest computer models of object recognition were based on structural descriptions in 3-D object-centered reference frames. According to most early structural description theories, object recognition is accomplished by using the 2-D image of an object to derive a 3-D structural description, which is then matched against similar descriptions stored in memory. Some view-matching models exploit specific transformations, such as translation, scaling, and rotation, to bring novel images into correspondence with a small number of stored views.

Presents information on the computational model called LISA (Learning and Interference with Schemes and Analogies) with reference to its integrated theory of analogical access and mapping. What are the characteristics of the model; Discussion on the analogical access and mapping; Information on the architecture and operation of LISA.

Presents a neural network that generates a viewpoint-invariant structural description specifying an object's parts and the relations among them. How structural description is made possible; What the model uses; Approaches to visual recognition; Method; Results; Discussion.

Simulation models are an important tool used in health care and other disciplines to support operational research and decision-making. In the child protection literature, simulation models are an under-utilized source of research evidence. In this paper, we describe the rationale for and the development of an agent-based simulation of a child protection system in the US. Using the investigation, prevention service, and placement histories of 600,000 children served in an urban child welfare system, we walk the reader through the development of a prototype known as OSPEDALE. The governing equations built into OSPEDALE probabilistically simulate the onset of investigations. Then, drawing from empirical survival distributions, the governing equations trace the probability of subsequent interactions with the system (recurrence of maltreatment, service referrals, and placement) conditional on the characteristics of children, their assessed risk level, and prior child protection system involvement. As an initial test of OSPEDALE 's utility, we compare empirical admission counts with counts generated from OSPEDALE. Though the verification step is admittedly simple, the comparison shows that OSPEDALE replicates the empirical count of new admissions closely enough to justify further investment in OSPEDALE. Management of public child protection systems is increasingly research evidence-dependent. The emphasis on research evidence as a decision-support tool has elevated evidence acquired through randomized clinical trials. Though important, the evidence from clinical trials represents only one type of research evidence. Properly specified, simulation models are another source of evidence with real-world relevance. [ABSTRACT FROM AUTHOR]

The author reflects on importance of Cardiac Magnetic resonance imaging (MRI) prior to repeat ablation of ventricular tachycardia. Topics discussed include Myocardial scar as the common substrate for ventricular tachycardia (VT) in the setting of underlying cardiomyopathy (CMP); advantages of a CMR guided ablation procedure; and adequacy and efficiency of the available ablation toolset.

Introduction: Among patients with non‐valvular atrial fibrillation (AF) and percutaneous left atrial appendage closure (LAAC) undergoing direct current cardioversion (DCCV), the need for and use of LAA imaging and oral anticoagulation (OAC) is unclear. Objective: The purpose of this study is to evaluate the real‐world use of transesophageal echocardiography (TEE) or cardiac computed tomography angiography (CCTA) before DCCV and use of OAC pre‐ and post‐DCCV in patients with AF status post percutaneous LAAC. Methods: This retrospective single center study included all patients who underwent DCCV after percutaneous LAAC from 2016 to 2022. Key measures were completion of TEE or CCTA pre‐DCCV, OAC use pre‐ and post‐DCCV, incidence of left atrial thrombus (LAT) or device‐related thrombus (DRT), incidence of peri‐device leak (PDL), and DCCV‐related complications (stroke, systemic embolism, device embolization, major bleeding, or death) within 30 days. Results: A total of 76 patients with AF and LAAC underwent 122 cases of DCCV. LAAC consisted of 47 (62%), 28 (37%), and 1 (1%) case of Watchman 2.5, Watchman FLX, and Lariat, respectively. Among the 122 DCCV cases, 31 (25%) cases were identified as "non‐guideline based" due to: (1) no OAC for 3 weeks and no LAA imaging within 48 h before DCCV in 12 (10%) cases, (2) no OAC for 4 weeks following DCCV in 16 (13%) cases, or (3) both in 3 (2%) cases. Among the 70 (57%) cases that underwent TEE or CCTA before DCCV, 16 (23%) cases had a PDL with a mean size of 3.0 ± 1.1 mm, and 4 (6%) cases had a LAT/DRT on TEE resulting in cancellation. There were no DCCV‐related complications within 30 days. Discussion: There is a widely varied practice pattern of TEE, CCTA, and OAC use with DCCV after LAAC, with a 6% rate of LAT/DRT. LAA imaging before DCCV appears prudent in all cases, especially within 1 year of LAAC, to assess for device position, PDL, and LAT/DRT. [ABSTRACT FROM AUTHOR]

In this article the authors discuss the benefits and disadvantages which are associated with deep sedation and general anesthesia in patients undergoing atrial fibrillation ablation. In the article the authors offer their opinions on several points which are raised in the article "Deep Sedation for Catheter Ablation of Atrial Fibrillation:A Prospective Study in 650 Consecutive Patients" by H. Kottkamp, G. Hindricks, C. Eitel, K. Muller, A. Siedziako, J. Koch, M. Anastasiou, C. Varounis, A. Arya, P. Sommer, T. Gaspar, C. Piorkowski and N. Dagres.

Humans, including preschool children, exhibit role-based relational reasoning, of which analogical reasoning is a canonical example. The "role-less" connectionist model proposed in the target article is only capable of conditional paired-associate learning. [ABSTRACT FROM AUTHOR]

The article comments on the evolution of curative ablation of atrial fibrillation (AF) from a surgical procedure to a percutaneous technique that has experienced a rapid time course despite the complexities of the clinical problem. The time period from the first description of pulmonary vein triggers and the elimination of AF by their ablation to the subsequent development of a reasonably safe and routine procedure routinely used in large ablation programs spans around 5 years.

The article comments on the study regarding cryoablation of atrial fibrillation. Cryoablation systems incorporate a mechanism to occlude pulmonary vein (PV) flow during lesion formation that may result in a higher percentage of permanent PV isolation. A noted advantage of this new circular cryoablation system is the ability to isolate a PV in an expedient manner. Isolation of a single vein PV can require 60 minutes of cryothermy. The reduced time to achieve acute PV isolation with the 64-mm freezing segment of this cryocatheter likely accounts for decreased fluoroscopy time and enhances the clinical feasibility of PV isolation using cryoablation.

Deals with the role of localist mental representations as the starting point for connectionist representations of symbolic or relational structures. Significance of localist nodes for the representation of relational structures; Notion of a localist representation.

Background: Transesophageal echocardiography (TEE) and cardiac computed tomography angiography (CCTA) are currently utilized for left atrial appendage closure (LAAC) planning. During the recent global iodine contrast media shortage in 2022, cardiac magnetic resonance imaging (CMR) was utilized for the first time for LAAC planning. This study sought to assess the utility of CMR versus TEE for LAAC planning. Methods: This single center retrospective study consisted of all patients who underwent preoperative CMR for LAAC with Watchman FLX or Amplatzer Amulet. Key measures were accuracy of LAA thrombus exclusion, ostial diameter, depth, lobe count, morphology, accuracy of predicted device size, and devices deployed per case. Bland‐Altman Analysis was used to compare CMR versus TEE measurements of LAA ostial diameter and depth. Results: 25 patients underwent preoperative CMR for LAAC planning. A total of 24 (96%) cases were successfully completed with 1.2 ± 0.5 devices deployed per case. Among the 18 patients who underwent intraoperative TEE, there was no significant difference between CMR versus TEE in LAA thrombus exclusion (CMR 83% vs. TEE 100% cases, p =.229), lobe count (CMR 1.7 ± 0.8 vs. TEE 1.4 ± 0.6, p =.177), morphology (p =.422), and accuracy of predicted device size (CMR 67% vs. TEE 72% cases, p = 1.000). When comparing the difference between CMR and TEE measurements, Bland‐Altman analysis demonstrated no significant difference in LAA ostial diameter (CMR‐TEE bias 0.7 mm, 95% CI [−1.1, 2.4], p =.420), but LAA depth was significantly larger with CMR versus TEE (CMR‐TEE bias 7.4 mm, 95% CI [1.6, 13.2], p =.015). Conclusions: CMR is a promising alternative for LAAC planning in cases where TEE or CCTA are contraindicated or unavailable. [ABSTRACT FROM AUTHOR]

The article offers information on First clinical use of real‐time remote programming in cardiac implantable electronic devices. It mentions technology that affords real‐time remote testing and programming of a cardiac implantable electronic device (CIED) without the need for clinical device specialists (manufacturer's representatives and device clinic nurses) in the electrophysiology (EP) lab.