bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variation in Hospital Risk–Adjusted Mortality Rates Following Transcatheter Aortic Valve Replacement in the United States
Authors: O’Brien Sean M. , Cohen David J. , Rumsfeld John S. , Brennan J. Matthew , Shahian David M. , Dai David , Holmes David R. , Hakim Rosemarie B. , Thourani Vinod H. , Peterson Eric D. , Edwards Fred H. 
Published: September 2016

Background—
The use of transcatheter aortic valve replacement (TAVR) to treat aortic stenosis in the United States is growing, yet little is known about the variation in procedural outcomes in community practice. We developed a TAVR in-hospital mortality risk model and used it to quantify variation in mortality rates across United States (US) TAVR centers.

Methods and Results—
We analyzed data from 22 248 TAVR procedures performed at 318 sites participating in the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry (November 2011 to October 2014). A Bayesian hierarchical model was developed to estimate hospital-specific risk-adjusted mortality rates adjusting for 40 patient baseline factors. A total of 1130 in-hospital deaths (5.1%) were observed. Reliability-adjusted risk-adjusted mortality rate estimates ranged from 3.4% to 7.7% with an interquartile range of 4.8% to 5.4%. A patient’s predicted odds of dying was 80% higher if treated by a hospital 1 standard deviation above the mean compared with a hospital 1 standard deviation below the mean (odds ratio =1.8; 95% credible interval, 1.4%–2.2%).

Conclusions—
Risk modeling of TAVR in-hospital mortality revealed variation in risk-adjusted mortality rates during the US early commercial experience. Transcatheter Valve Therapy Registry analyses using this model will support research, feedback reporting, and the identification of factors associated with quality.
Regional Learning Collaboratives Produce Rapid and Sustainable Improvements in Stroke Thrombolysis Times
Authors: Prabhakaran Shyam , Lee Jungwha , O’Neill Kathleen 
Published: September 2016

Background—
Reduction in door-to-needle (DTN) times in patients with acute ischemic stroke treated with tissue-type plasminogen activator is associated with improved outcomes. We hypothesized that a learning collaborative would rapidly reduce DTN times at Chicago’s primary stroke centers.

Methods and Results—

We analyzed data from all adult patients with out-of-hospital ischemic stroke hospitalized between January 1, 2010 and March 31, 2015 and who received tissue-type plasminogen activator in the emergency department at 15 primary stroke centers in Chicago and 15 primary stroke centers in St. Louis. We implemented a structured learning collaborative in Chicago in quarter 1 of 2013 that included (1) a quality improvement leader, (2) stroke content expert, (3) multidisciplinary teams from each site, (4) a targeted goal for the program (DTN time <60 minutes in >50% of patients treated with tissue-type plasminogen activator), and (5) face-to-face meetings with on-site visits. We used interrupted time-series analysis to compare the impact of the learning collaborative on DTN times in Chicago pre- and post implementation and also concurrently versus St. Louis. We prespecified adjustment for mode of arrival, emergency medical services prenotification, and onset-to-arrival times.
P
values less than 0.05 were considered significant. In adjusted analysis, the reduction in DTN time within 1 quarter of implementation was 15.5 minutes (
P
=0.046) at Chicago sites versus 1.17 minutes at St. Louis sites (
P
=0.601).

Conclusions—
Using a learning collaborative model at Chicago’s 15 primary stroke centers, we observed major reductions in DTN times within 1 quarter of implementation. Regional collaboration and best practices sharing should be a model for rapid and sustainable system-wide quality improvement.
Blood Flow Into Basilar Tip Aneurysms
Authors: Sugiyama Shin-ichiro , Niizuma Kuniyasu , Sato Kenichi , Rashad Sherif , Kohama Misaki , Endo Hidenori , Endo Toshiki , Matsumoto Yasushi , Ohta Makoto , Tominaga Teiji 
Published: September 2016

Background and Purpose—
Hemodynamic forces may play a role in the recanalization of coiled aneurysms. The purpose of this study was to investigate the influence of presurgical hemodynamics on the efficacy of coil embolization for basilar tip aneurysms.

Methods—
We identified 82 patients who underwent endovascular coil embolization for basilar tip aneurysms with a follow-up of >1 year. Presurgical hemodynamics were investigated using computational fluid dynamics with 3-dimensional data derived from rotational angiography. During postprocessing, we quantified the rate of net flow entering the aneurysm through its neck and calculated the proportion of the aneurysmal inflow rate to the basilar artery flow rate. In addition, we investigated the correlation between the basilar bifurcation configuration and the hemodynamics.

Results—
Twenty-five of the 82 patients were excluded because of difficult vascular geometry reconstruction. Among the 57 examined patients, angiographic recanalization was observed in 19 patients (33.3%). The proportion of the aneurysmal inflow rate to the basilar artery flow rate and a coil packing density <30% were independent and significant predictors for the recanalization of coiled aneurysms. Additional investigation revealed that a small branch angle formed by the basilar artery and the posterior cerebral artery increased blood flow into the aneurysm.

Conclusions—
The proportion of the aneurysmal inflow rate to the basilar artery flow rate, influenced by the basilar bifurcation configuration, was an independent and significant predictor for recanalization after coil embolization in basilar tip aneurysms.
Antiphospholipid Antibodies and the Risk of Stroke in Urban and Rural Tanzania
Authors: de Mast Quirijn , Molhoek Jessica E. , van der Ven André J. , Gray William K. , de Groot Philip G. , Jusabani Ahmed , Mugusi Ferdinand , Urbanus Rolf T. , Walker Richard W. 
Published: September 2016

Background and Purpose—
The burden of stroke is high in sub-Saharan Africa, and improved knowledge of risk factors is needed. Antiphospholipid antibodies are a common acquired stroke risk factor in young individuals. Antiphospholipid antibodies may be induced by infectious diseases. Sub-Saharan Africa has a high infectious burden, and we analyzed the contribution of antiphospholipid antibodies to the risk of stroke in an incident population from rural and urban Tanzania.

Methods—

Stroke cases and age- and sex-matched community-acquired controls from the rural Hai district and urban Dar-es-Salaam areas of Tanzania were recruited in a wider study of stroke incidence between June 2003 and June 2006. Lupus anticoagulant, anticardiolipin, anti-β2-glycoprotein I, and antiphosphatidylserine/prothrombin antibodies were determined in stored plasma, as well as IgG antibodies against
Treponema pallidum
.

Results—

Data from 158 stroke cases and 369 controls were analyzed. Thirty cases (19%) and 4 controls (1%) had a lupus anticoagulant (odds ratio, 20.8; 95% confidence interval, 7.2–60.5). Anticardiolipin IgG was the only other antiphospholipid antibody subtype associated with increased stroke risk (odds ratio, 2.1; 95% confidence interval, 1.0–4.3), but this association disappeared when corrected for IgG antibodies against
Treponema pallidum
results. The prevalence of anti-β2-glycoprotein I IgG antibodies in the Tanzanian healthy population was high when Dutch cutoff values were applied (67%), whereas presence of anti-β2-glycoprotein I IgM was associated with a reduced stroke risk (odds ratio 0.3; 95% confidence interval, 0.1–1.1).

Conclusions—
The presence of lupus anticoagulant is a strong, and to date unrecognized, risk factor for stroke in Tanzania, especially in young and middle-aged individuals.
Applicability of Clinical Trials in an Unselected Cohort of Patients With Intracerebral Hemorrhage
Authors: Hansen Björn M. , Ullman Natalie , Norrving Bo , Hanley Daniel F. , Lindgren Arne 
Published: September 2016

Background and Purpose—
Patient selection in clinical trials on intracerebral hemorrhage (ICH) affects overall applicability of results. We estimated eligibility for completed, ongoing, and planned clinical trials in an unselected cohort of patients with ICH.

Methods—
Large clinical ICH trials were identified using trial registration databases. Each trial’s inclusion criteria were applied to a consecutive group of patients with ICH from the prospective hospital-based Lund Stroke Register. Survival status was obtained from the National Census Office and 90-day poor functional outcome (modified Rankin Scale ≥4) from the Swedish Stroke Register or medical files.

Results—

Among 253 patients with ICH, estimated eligibility proportions ranged between 2% and 36% for the 11 identified clinical trials. Patients not eligible for any trial (n=96) had more intraventricular hemorrhage, lower baseline level of consciousness, higher rates of cerebellar ICH, and lower rates of lobar ICH (
P
≤0.001). Thirty-day case fatality for noneligible patients was 54% versus 18% among patients eligible in ≥1 trial (95% confidence interval, 44%–64% versus 13%–25%;
P
<0.001). Noneligible ICH patients more frequently had poor functional outcome (75% versus 48%; 95% confidence interval, 65%–83% versus 40%–56%;
P
<0.001).

Conclusions—
There is large variation in proportions of patients with ICH eligible for inclusion in clinical trials and over a third of patients with ICH are not eligible for any trial.
Rhythmic Activity and Individual Variability in Recognition Memory: Theta Oscillations Correlate with Performance whereas Alpha Oscillations Correlate with ERPs
Authors: Chen Yvonne Y. , Caplan Jeremy B. 
Published: September 2016

AbstractDuring study trials of a recognition memory task, alpha (∼10 Hz) oscillations decrease, and concurrently, theta (4–8 Hz) oscillations increase when later memory is successful versus unsuccessful (subsequent memory effect). Likewise, at test, reduced alpha and increased theta activity are associated with successful memory (retrieval success effect). Here we take an individual-differences approach to test three hypotheses about theta and alpha oscillations in verbal, old/new recognition, measuring the difference in oscillations between hit trials and miss trials. First, we test the hypothesis that theta and alpha oscillations have a moderately mutually exclusive relationship; but no support for this hypothesis was found. Second, we test the hypothesis that theta oscillations explain not only memory effects within participants, but also individual differences. Supporting this prediction, durations of theta (but not alpha) oscillations at study and at test correlated significantly with d′ across participants. Third, we test the hypothesis that theta and alpha oscillations reflect familiarity and recollection processes by comparing oscillation measures to ERPs that are implicated in familiarity and recollection. The alpha-oscillation effects correlated with some ERP measures, but inversely, suggesting that the actions of alpha oscillations on memory processes are distinct from the roles of familiarity- and recollection-linked ERP signals. The theta-oscillation measures, despite differentiating hits from misses, did not correlate with any ERP measure; thus, theta oscillations may reflect elaborative processes not tapped by recollection-related ERPs. Our findings are consistent with alpha oscillations reflecting visual inattention, which can modulate memory, and with theta oscillations supporting recognition memory in ways that complement the most commonly studied ERPs.
Sleep Spindles and Intellectual Ability: Epiphenomenon or Directly Related?
Authors: Fang Zhuo , Sergeeva Valya , Ray Laura B. , Viczko Jeremy , Owen Adrian M. , Fogel Stuart M. 
Published: September 2016

Abstract
Sleep spindles—short, phasic, oscillatory bursts of activity that characterize non-rapid eye movement sleep—are one of the only electrophysiological oscillations identified as a biological marker of human intelligence (e.g., cognitive abilities commonly assessed using intelligence quotient tests). However, spindles are also important for sleep maintenance and are modulated by circadian factors. Thus, the possibility remains that the relationship between spindles and intelligence quotient may be an epiphenomenon of a putative relationship between good quality sleep and cognitive ability or perhaps modulated by circadian factors such as morningness–eveningness tendencies. We sought to ascertain whether spindles are directly or indirectly related to cognitive abilities using mediation analysis. Here, we show that fast (13.5–16 Hz) parietal but not slow (11–13.5 Hz) frontal spindles in both non-rapid eye movement stage 2 sleep and slow wave sleep are directly related to reasoning abilities (i.e., cognitive abilities that support “fluid intelligence,” such as the capacity to identify complex patterns and relationships and the use of logic to solve novel problems) but not verbal abilities (i.e., cognitive abilities that support “crystalized intelligence”; accumulated knowledge and experience) or cognitive abilities that support STM (i.e., the capacity to briefly maintain information in an available state). The relationship between fast spindles and reasoning abilities is independent of the indicators of sleep maintenance and circadian chronotype, thus suggesting that spindles are indeed a biological marker of cognitive abilities and can serve as a window to further explore the physiological and biological substrates that give rise to human intelligence.
Frontostriatal Contribution to the Interplay of Flexibility and Stability in Serial Prediction
Authors: Trempler Ima , Schiffer Anne-Marike , El-Sourani Nadiya , Ahlheim Christiane , Fink Gereon R. , Schubotz Ricarda I. 
Published: September 2016

Abstract
Surprising events may be relevant or irrelevant for behavior, requiring either flexible adjustment or stabilization of our model of the world and according response strategies. Cognitive flexibility and stability in response to environmental demands have been described as separable cognitive states, associated with activity of striatal and lateral prefrontal regions, respectively. It so far remains unclear, however, whether these two states act in an antagonistic fashion and which neural mechanisms mediate the selection of respective responses, on the one hand, and a transition between these states, on the other. In this study, we tested whether the functional dichotomy between striatal and prefrontal activity applies for the separate functions of updating (in response to changes in the environment, i.e., switches) and shielding (in response to chance occurrences of events violating expectations, i.e., drifts) of current predictions. We measured brain activity using fMRI while 20 healthy participants performed a task that required to serially predict upcoming items. Switches between predictable sequences had to be indicated via button press while sequence omissions (drifts) had to be ignored. We further varied the probability of switches and drifts to assess the neural network supporting the transition between flexible and stable cognitive states as a function of recent performance history in response to environmental demands. Flexible switching between models was associated with activation in medial pFC (BA 9 and BA 10), whereas stable maintenance of the internal model corresponded to activation in the lateral pFC (BA 6 and inferior frontal gyrus). Our findings extend previous studies on the interplay of flexibility and stability, suggesting that different prefrontal regions are activated by different types of prediction errors, dependent on their behavioral requirements. Furthermore, we found that striatal activation in response to switches and drifts was modulated by participants' successful behavior toward these events, suggesting the striatum to be responsible for response selections following unpredicted stimuli. Finally, we observed that the dopaminergic midbrain modulates the transition between different cognitive states, thresholded by participants' individual performance history in response to temporal environmental demands.
On the Role of the Inferior Intraparietal Sulcus in Visual Working Memory for Lateralized Single-feature Objects
Authors: Brigadoi Sabrina , Cutini Simone , Meconi Federica , Castellaro Marco , Sessa Paola , Marangon Mattia , Bertoldo Alessandra , Jolicœur Pierre , Dell'Acqua Roberto 
Published: September 2016

Abstract
A consolidated practice in cognitive neuroscience is to explore the properties of human visual working memory through the analysis of electromagnetic signals using cued change detection tasks. Under these conditions, EEG/MEG activity increments in the posterior parietal cortex scaling with the number of memoranda are often reported in the hemisphere contralateral to the objects' position in the memory array. This highly replicable finding clashes with several reported failures to observe compatible hemodynamic activity modulations using fMRI or fNIRS in comparable tasks. Here, we reconcile this apparent discrepancy by acquiring fMRI data on healthy participants and employing a cluster analysis to group voxels in the posterior parietal cortex based on their functional response. The analysis identified two distinct subpopulations of voxels in the intraparietal sulcus (IPS) showing a consistent functional response among participants. One subpopulation, located in the superior IPS, showed a bilateral response to the number of objects coded in visual working memory. A different subpopulation, located in the inferior IPS, showed an increased unilateral response when the objects were displayed contralaterally. The results suggest that a cluster of neurons in the inferior IPS is a candidate source of electromagnetic contralateral responses to working memory load in cued change detection tasks.
Continuous Online Sequence Learning with an Unsupervised Neural Network
Model
Authors: Cui Yuwei , Ahmad Subutai , Hawkins Jeff 
Published: September 2016

Abstract
The ability to recognize and predict temporal sequences of sensory inputs is vital for survival in natural environments. Based on many known properties of cortical neurons, hierarchical temporal memory (HTM) sequence memory recently has been proposed as a theoretical framework for sequence learning in the cortex. In this letter, we analyze properties of HTM sequence memory and apply it to sequence learning and prediction problems with streaming data. We show the model is able to continuously learn a large number of variable order temporal sequences using an unsupervised Hebbian-like learning rule. The sparse temporal codes formed by the model can robustly handle branching temporal sequences by maintaining multiple predictions until there is sufficient disambiguating evidence. We compare the HTM sequence memory with other sequence learning algorithms, including statistical methods—autoregressive integrated moving average; feedforward neural networks—time delay neural network and online sequential extreme learning machine; and recurrent neural networks—long short-term memory and echo-state networks on sequence prediction problems with both artificial and real-world data. The HTM model achieves comparable accuracy to other state-of-the-art algorithms. The model also exhibits properties that are critical for sequence learning, including continuous online learning, the ability to handle multiple predictions and branching sequences with high-order statistics, robustness to sensor noise and fault tolerance, and good performance without task-specific hyperparameter tuning. Therefore, the HTM sequence memory not only advances our understanding of how the brain may solve the sequence learning problem but is also applicable to real-world sequence learning problems from continuous data streams.
The Lamellar Structure of the Brain Fiber Pathways
Authors: Galinsky Vitaly L. , Frank Lawrence R. 
Published: September 2016

We present a quantitative statistical analysis of pairwise crossings for all fibers obtained from whole brain tractography that confirms with high confidence that the brain grid theory (Wedeen et al., 2012a ) is not supported by the evidence. The overall fiber tracts structure appears to be more consistent with small angle treelike branching of tracts rather than with near-orthogonal gridlike crossing of fiber sheets. The analysis uses our new method for high-resolution whole brain tractography that is capable of resolving fibers crossing of less than 10 degrees and correctly following a continuous angular distribution of fibers even when the individual fiber directions are not resolved. This analysis also allows us to demonstrate that the whole brain fiber pathway system is very well approximated by a lamellar vector field, providing a concise and quantitative mathematical characterization of the structural connectivity of the human brain.
Four Paraphrases and a Gospel or How to Rewrite Without Repeating Yourself
Authors: Cottier Jean-François 
Published: September 2016

In his preface to Emperor Charles V, Erasmus denies any intention of making his Paraphrases on the Gospels an evangelical harmony that would contradict his desire for legibility.1 We can therefore assume that, when in paraphrasing one gospel he has recourse to another, he does so for the sake of clarity, as when he proposes a harmonized version of the baptism of Christ or of his passion. Based on a textual comparison of certain passages from the Paraphrases on Matthew, Mark, Luke, and John, this article studies how Erasmus rewrites the text of the four gospels, reconciling them without repeating himself, while conserving to each its own unique character.
A Comparison of X-Band Polarization Parameters with In Situ Microphysical Measurements in the Comma Head of Two Winter Cyclones
Authors: Finlon Joseph A. , McFarquhar Greg M. , Rauber Robert M. , Plummer David M. , Jewett Brian F. , Leon David , Knupp Kevin R. 
Published: September 2016

AbstractSince the advent of dual-polarization radar, methods of classifying hydrometeors by type from measured polarization variables have been developed. The deterministic approach of existing hydrometeor classification algorithms of assigning only one dominant habit to each radar sample volume does not properly consider the distribution of habits present in that volume, however. During the Profiling of Winter Storms field campaign, the “NSF/NCAR C-130” aircraft, equipped with in situ microphysical probes, made multiple passes through the comma heads of two cyclones as the Mobile Alabama X-band dual-polarization radar performed range–height indicator scans in the same plane as the C-130 flight track. On 14–15 February and 21–22 February 2010, 579 and 202 coincident data points, respectively, were identified when the plane was within 10 s (~1 km) of a radar gate. For all particles that occurred for times within different binned intervals of radar reflectivity ZHH and of differential reflectivity ZDR, the reflectivity-weighted contribution of each habit and the frequency distributions of axis ratio and sphericity were determined. This permitted the determination of habits that dominate particular ZHH and ZDR intervals; only 40% of the ZHH–ZDR bins were found to have a habit that contributes over 50% to the reflectivity in that bin. Of these bins, only 12% had a habit that contributes over 75% to the reflectivity. These findings show the general lack of dominance of a given habit for a particular ZHH and ZDR and suggest that determining the probability of specific habits in radar volumes may be more suitable than the deterministic methods currently used.