bluuebunny/crossref_metadata_2025 huggingface dataset:
Left ventricular energetics: new insight into the plasticity of regional contributions at rest and during exercise
Authors: Stöhr Eric J. , González-Alonso José , Bezodis Ian N. , Shave Rob
Published: November 2013

Although the human left ventricle (LV) operates as a functional syncytium and previous studies have reported a single value for LV stroke work at rest, more intricate plasticity of regional LV energetics may be required during enhanced cardiovascular demand. We compared kinetic energy of the LV base and apex, respectively, during ventricular contraction and relaxation at rest and during continuous and discontinuous incremental exercise. At rest, prior to both exercise trials, the accumulated kinetic energy during contraction and relaxation was significantly higher at the LV base compared with the apex ( P ≤ 0.05). With increasing exercise intensity, kinetic energy during contraction increased significantly more at the LV base (interaction effect: P < 0.0001), while kinetic energy during relaxation increased significantly more at the apex during high-intensity exercise (interaction effect: P < 0.001). Total kinetic energy produced over the entire cardiac cycle was significantly greater at the LV apex during high exercise intensities ( P < 0.05). We further show that the region-specific differences in kinetic energy at rest and during exercise are explained by significantly different wall mechanics, showing heterogenic contributions from radial, circumferential, and angular components at the base and apex, respectively. In conclusion, the present findings provide unique insight into human LV function by demonstrating that within this functional syncytium, significant differences in the regional contributions of kinetic energy to overall LV work exist. Importantly, regional contributions are not fixed but highly plastic and the underpinning LV wall energetics adjust according to the prevailing cardiovascular demand.
Nox-derived ROS are acutely activated in pressure overload pulmonary hypertension: indications for a seminal role for mitochondrial Nox4
Authors: Frazziano Giovanna , Al Ghouleh Imad , Baust Jeff , Shiva Sruti , Champion Hunter C. , Pagano Patrick J.
Published: November 2013

Pulmonary arterial hypertension is a severe progressive disease with marked morbidity and high mortality in which right ventricular (RV) failure is the major cause of death. Thus knowledge of the mechanisms underlying RV failure is an area of active interest. Previous studies suggest a role of NADPH oxidase in cardiomyocyte dysfunction in the left heart. Here we postulate that acute pressure overload induced by pulmonary artery banding (PAB) leads to a Nox4-initiated increase in reactive oxygen species (ROS) in mouse RV that may lead to feed-forward induction of Nox2. To test our hypothesis, ROS production was measured in RV and left ventricle homogenates. The data show that hydrogen peroxide (H2O2), but not superoxide anion (O2·−), was increased in the early phases (within 6 h) of PAB in RV and that this increase was diminished by catalase and diphenyleneiodonium chloride but not by SOD, Nω-nitro-l-arginin methyl ester, febuxostat, or indomethacin. H2O2 production in RV was not attenuated in Nox2 null mice subjected to 6 h PAB. Moreover, we observed an upregulation of Nox4 mRNA after 1 h of PAB and an increase in mitochondrial Nox4 protein 6 h post-PAB. In contrast, we observed an increase in Nox2 mRNA 1 day post-PAB. Expression of antioxidant enzymes SOD, catalase, and glutathione peroxidase did not change, but catalase activity increased 6 h post-PAB. Taken together, these findings show a role of mitochondria-localized Nox4 in the early phase of PAB and suggest an involvement of this isozyme in early ROS generation possibly contributing to progression of RV dysfunction and failure.
Preclinical evaluation of human secretoglobin 3A2 in mouse models of lung development and fibrosis
Authors: Cai Yan , Winn Melissa E. , Zehmer John K. , Gillette William K. , Lubkowski Jacek T. , Pilon Aprile L. , Kimura Shioko
Published: November 2013

Secretoglobin (SCGB) 3A2 is a member of the SCGB gene superfamily of small secreted proteins, predominantly expressed in lung airways. We hypothesize that human SCGB3A2 may exhibit anti-inflammatory, growth factor, and antifibrotic activities and be of clinical utility. Recombinant human SCGB3A2 was expressed, purified, and biochemically characterized as a first step to its development as a therapeutic agent in clinical settings. Human SCGB3A2, as well as mouse SCGB3A2, readily formed a dimer in solution and exhibited novel phospholipase A2 inhibitory activity. This is the first demonstration of any quantitative biochemical measurement for the evaluation of SCGB3A2 protein. In the mouse as an experimental animal, human SCGB3A2 exhibited growth factor activity by promoting embryonic lung development in both ex vivo and in vivo systems and antifibrotic activity in the bleomycin-induced lung fibrosis model. The results suggested that human SCGB3A2 can function as a growth factor and an antifibrotic agent in humans. When SCGB3A2 was administered to pregnant female mice through the tail vein, the protein was detected in the dam's serum and lung, as well as the placenta, amniotic fluids, and embryonic lungs at 10 min postadministration, suggesting that SCGB3A2 readily crosses the placenta. The results warrant further development of recombinant SCGB3A2 as a therapeutic agent in treating patients suffering from lung diseases or preterm infants with respiratory distress.
Deletion of airway cilia results in noninflammatory bronchiectasis and hyperreactive airways
Authors: Gilley Sandra K. , Stenbit Antine E. , Pasek Raymond C. , Sas Kelli M. , Steele Stacy L. , Amria May , Bunni Marlene A. , Estell Kimberly P. , Schwiebert Lisa M. , Flume Patrick , Gooz Monika , Haycraft Courtney J. , Yoder Bradley K. , Miller Caroline , Pavlik Jacqueline A. , Turner Grant A. , Sisson Joseph H. , Bell P. Darwin
Published: November 2013

The mechanisms for the development of bronchiectasis and airway hyperreactivity have not been fully elucidated. Although genetic, acquired diseases and environmental influences may play a role, it is also possible that motile cilia can influence this disease process. We hypothesized that deletion of a key intraflagellar transport molecule, IFT88, in mature mice causes loss of cilia, resulting in airway remodeling. Airway cilia were deleted by knockout of IFT88, and airway remodeling and pulmonary function were evaluated. In IFT88− mice there was a substantial loss of airway cilia on respiratory epithelium. Three months after the deletion of cilia, there was clear evidence for bronchial remodeling that was not associated with inflammation or apparent defects in mucus clearance. There was evidence for airway epithelial cell hypertrophy and hyperplasia. IFT88− mice exhibited increased airway reactivity to a methacholine challenge and decreased ciliary beat frequency in the few remaining cells that possessed cilia. With deletion of respiratory cilia there was a marked increase in the number of club cells as seen by scanning electron microscopy. We suggest that airway remodeling may be exacerbated by the presence of club cells, since these cells are involved in airway repair. Club cells may be prevented from differentiating into respiratory epithelial cells because of a lack of IFT88 protein that is necessary to form a single nonmotile cilium. This monocilium is a prerequisite for these progenitor cells to transition into respiratory epithelial cells. In conclusion, motile cilia may play an important role in controlling airway structure and function.
Proteomic landscape of bronchoalveolar lavage fluid in human immunodeficiency virus infection
Authors: Nguyen Elizabeth V. , Gharib Sina A. , Crothers Kristina , Chow Yu-Hua , Park David R. , Goodlett David R. , Schnapp Lynn M.
Published: November 2013

The lung is an important reservoir of human immunodeficiency virus (HIV). Individuals infected with HIV are more prone to pulmonary infections and chronic lung disorders. We hypothesized that comprehensively profiling the proteomic landscape of bronchoalveolar lavage fluid (BALF) in patients with HIV would provide insights into how this virus alters the lung milieu and contributes to pathogenesis of HIV-related lung diseases. BALF was obtained from five HIV-negative (HIV−) and six asymptomatic HIV-positive (HIV+) subjects not on antiretroviral therapy. Each sample underwent shotgun proteomic analysis based on HPLC-tandem mass spectrometry. Differentially expressed proteins between the groups were identified using statistical methods based on spectral counting. Mechanisms of disease were explored using functional annotation to identify overlapping and distinct pathways enriched between the BALF proteome of HIV+ and HIV− subjects. We identified a total of 318 unique proteins in BALF of HIV− and HIV+ subjects. Of these, 87 were differentially up- or downregulated between the two groups. Many of these differentially expressed proteins are known to interact with key HIV proteins. Functional analysis of differentially regulated proteins implicated downregulation of immune responses in lungs of HIV+ patients. Combining shotgun proteomic analysis with computational methods demonstrated that the BALF proteome is significantly altered during HIV infection. We found that immunity-related pathways are underrepresented in HIV+ patients. These findings implicate mechanisms whereby HIV invokes local immunosuppression in the lung and increases the susceptibility of HIV+ patients to develop a wide range of infectious and noninfectious pulmonary diseases.
F-actin scaffold stabilizes lamellar bodies during surfactant secretion
Authors: Islam Mohammad N. , Gusarova Galina A. , Monma Eiji , Das Shonit R. , Bhattacharya Jahar
Published: November 2013

Alveolar type 2 (AT2) cells secrete surfactant that forms a protective layer on the lung's alveolar epithelium. Vesicles called lamellar bodies (LBs) store surfactant. Failure of surfactant secretion, which causes severe lung disease, relates to the manner in which LBs undergo exocytosis during the secretion. However, the dynamics of LBs during the secretion process are not known in intact alveoli. Here, we addressed this question through real-time confocal microscopy of single AT2 cells in live alveoli of mouse lungs. Using a combination of phospholipid and aqueous fluorophores that localize to LBs, we induced surfactant secretion by transiently hyperinflating the lung, and we quantified the secretion in terms of loss of bulk LB fluorescence. In addition, we quantified inter-LB phospholipid flow through determinations of fluorescence recovery after photobleaching. Furthermore, we determined the role of F-actin in surfactant secretion through expression of the fluorescent F-actin probe Lifeact. Our findings indicate that, in AT2 cells in situ, LBs are held in an F-actin scaffold. Although F-actin transiently decreases during surfactant secretion, the LBs remain stationary, forming a chain of vesicles connected by intervesicular channels that convey surfactant to the secretion site on the plasma membrane. This is the first instance of a secretory process in which the secretory vesicles are immobile, but form a conduit for the secretory material.
Recent advances in late lung development and the pathogenesis of bronchopulmonary dysplasia
Authors: Madurga Alicia , Mižíková Ivana , Ruiz-Camp Jordi , Morty Rory E.
Published: November 2013

In contrast to early lung development, a process exemplified by the branching of the developing airways, the later development of the immature lung remains very poorly understood. A key event in late lung development is secondary septation, in which secondary septa arise from primary septa, creating a greater number of alveoli of a smaller size, which dramatically expands the surface area over which gas exchange can take place. Secondary septation, together with architectural changes to the vascular structure of the lung that minimize the distance between the inspired air and the blood, are the objectives of late lung development. The process of late lung development is disturbed in bronchopulmonary dysplasia (BPD), a disease of prematurely born infants in which the structural development of the alveoli is blunted as a consequence of inflammation, volutrauma, and oxygen toxicity. This review aims to highlight notable recent developments in our understanding of late lung development and the pathogenesis of BPD.
Angiostatin inhibits acute lung injury in a mouse model
Authors: Aulakh Gurpreet K. , Suri Sarabjeet S. , Singh Baljit
Published: November 2013

Acute lung injury is marked by profound influx of activated neutrophils, which have delayed apoptosis, along with fluid accumulation that impairs lung function and causes high mortality. Inflammatory and antimicrobial molecules, such as reactive oxygen species from activated neutrophils with prolonged lifespan, cause tissue damage and contribute to lung dysfunction. Angiostatin, an endogenous antiangiogenic molecule, is expressed in the lavage fluid of patients with acute respiratory distress syndrome and modifies neutrophil infiltration in a mouse model of peritonitis. Our aim was to investigate the therapeutic role of angiostatin in acute lung injury. We analyzed bronchoalveolar lavage and lung tissues from C57BL/6 mouse model of Escherichia coli LPS-induced acute lung injury to assess the effects of angiostatin treatment. Subcutaneous angiostatin administered at 5 h after LPS treatment reduces histological signs of inflammation, protein accumulation, lung Gr1+ neutrophils, myeloperoxidase activity, and expression of phosphorylated p38 MAPK in lung tissues and peripheral blood neutrophils, while increasing the number of apoptotic cells in the lungs without affecting the levels of macrophage inflammatory protein-1 α, IL-1β, keratinocyte chemoattractant, and monocyte chemoattractant protein-1 in lavage and lung homogenates at 9 and 24 h after LPS treatment. In contrast, angiostatin administered intravenously 5 h after LPS treatment did not reduce histological sign of inflammation, BAL cell recruitment, and protein concentration at 9 h of LPS treatment. We conclude that angiostatin administered subcutaneously after LPS challenge inhibits acute lung inflammation up to 24 h after LPS treatment.
Inflammatory Mechanisms of Idiopathic Epiretinal Membrane Formation
Authors: Joshi Malav , Agrawal Shivi , Christoforidis John Byron
Published: November 2013

The pathogenesis of idiopathic epiretinal membranes (iERMs), a common pathology found in retina clinics, still eludes researchers to date. Ultrastructural studies of iERMs in the past have failed to identify the cells of origin due to the striking morphologic changes of cells involved via transdifferentiation. Thus, immunohistochemical techniques that stain for the cytostructural components of cells have confirmed the importance of glial cells and hyalocytes in iERM formation. The cellular constituents of iERMs are thought to consist of glial cells, fibroblasts, hyalocytes, etc. that, in concert with cytokines and growth factors present in the vitreous, lead to iERM formation. Recently, research has focused on the role of the posterior hyaloid in iERM formation and contraction, particularly the process of anomalous PVD as it relates to iERM formation. Recent advances in proteomics techniques have also elucidated the growth factors and cytokines involved in iERM formation, most notably nerve growth factor, glial cell line-derived growth factor, and transforming growth factorβ1.
Exergaming as a Strategic Tool in the Fight against Childhood Obesity: A Systematic Review
Authors: Lamboglia Carminda Maria Goersch Fontenele , Silva Vanina Tereza Barbosa Lopes da , Vasconcelos Filho José Eurico de , Pinheiro Mônica Helena Neves Pereira , Munguba Marilene Calderaro da Silva , Silva Júnior Francisco Valmar Isaias , Paula Fernando Alberto Ramirez de , Silva Carlos Antônio Bruno da
Published: November 2013

Improper use of electronic media is considered a major contributing factor to childhood obesity. However, exergames, a new generation of active games, have made it possible to combine electronic entertainment with physical exercise. The purpose of this systematic review was to analyze the use of exergaming as a strategic tool in the fight against childhood obesity. Information was retrieved from the databases SciELO, LILACS, Pubmed, Ebsco, and Science Direct, using the search words “egames,” “exergames,” “exergaming,” “new generation of video games,” “active video games,” “energy expenditure,” “body composition,” and “physical activity” in English and Portuguese, covering the period January 2008 to April 2012. Nine articles met the inclusion criteria. Exergaming was found to increase physical activity levels, energy expenditure, maximal oxygen uptake, heart rate, and percentage of physical activity engaged in and to reduce waist circumference and sedentary screen time. Thus, exergaming may be considered a highly relevant strategic tool for the adoption of an active and healthy lifestyle and may be useful in the fight against childhood obesity.
Changes in Otx2 and Parvalbumin Immunoreactivity in the Superior Colliculus in the Platelet-Derived Growth Factor Receptor-βKnockout Mice
Authors: Zhao Juanjuan , Urakawa Susumu , Matsumoto Jumpei , Li Ruixi , Ishii Yoko , Sasahara Masakiyo , Peng Yuwen , Ono Taketoshi , Nishijo Hisao
Published: November 2013

The superior colliculus (SC), a relay nucleus in the subcortical visual pathways, is implicated in socioemotional behaviors. Homeoprotein Otx2 andβsubunit of receptors of platelet-derived growth factor (PDGFR-β) have been suggested to play an important role in development of the visual system and development and maturation of GABAergic neurons. Although PDGFR-β-knockout (KO) mice displayed socio-emotional deficits associated with parvalbumin (PV-)immunoreactive (IR) neurons, their anatomical bases in the SC were unknown. In the present study, Otx2 and PV-immunolabeling in the adult mouse SC were investigated in the PDGFR-βKO mice. Although there were no differences in distribution patterns of Otx2 and PV-IR cells between the wild type and PDGFR-βKO mice, the mean numbers of both of the Otx2- and PV-IR cells were significantly reduced in the PDGFR-βKO mice. Furthermore, average diameters of Otx2- and PV-IR cells were significantly reduced in the PDGFR-βKO mice. These findings suggest that PDGFR-βplays a critical role in the functional development of the SC through its effects on Otx2- and PV-IR cells, provided specific roles of Otx2 protein and PV-IR cells in the development of SC neurons and visual information processing, respectively.
Gene Network and Proteomic Analyses of Cardiac Responses to Pathological and Physiological Stress
Authors: Drozdov Ignat , Didangelos Athanasios , Yin Xiaoke , Zampetaki Anna , Abonnenc Mélanie , Murdoch Colin , Zhang Min , Ouzounis Christos A. , Mayr Manuel , Tsoka Sophia , Shah Ajay M.
Published: November 2013

Background—

The molecular mechanisms underlying similarities and differences between physiological and pathological left ventricular hypertrophy (LVH) are of intense interest. Most previous work involved targeted analysis of individual signaling pathways or screening of transcriptomic profiles. We developed a network biology approach using genomic and proteomic data to study the molecular patterns that distinguish pathological and physiological LVH.

Methods and Results—

A network-based analysis using graph theory methods was undertaken on 127 genome-wide expression arrays of in vivo murine LVH. This revealed phenotype-specific pathological and physiological gene coexpression networks. Despite >1650 common genes in the 2 networks, network structure is significantly different. This is largely because of rewiring of genes that are differentially coexpressed in the 2 networks; this novel concept of differential wiring was further validated experimentally. Functional analysis of the rewired network revealed several distinct cellular pathways and gene sets. Deeper exploration was undertaken by targeted proteomic analysis of mitochondrial, myofilament, and extracellular subproteomes in pathological LVH. A notable finding was that mRNA–protein correlation was greater at the cellular pathway level than for individual loci.

Conclusions—

This first combined gene network and proteomic analysis of LVH reveals novel insights into the integrated pathomechanisms that distinguish pathological versus physiological phenotypes. In particular, we identify differential gene wiring as a major distinguishing feature of these phenotypes. This approach provides a platform for the investigation of potentially novel pathways in LVH and offers a freely accessible protocol (
http://sites.google.com/site/cardionetworks
) for similar analyses in other cardiovascular diseases.
Transesophageal Echocardiography in Cryptogenic Stroke and Patent Foramen Ovale
Authors: Wessler Benjamin S. , Thaler David E. , Ruthazer Robin , Weimar Christian , Di Tullio Marco R. , Elkind Mitchell S.V. , Homma Shunichi , Lutz Jennifer S. , Mas Jean-Louis , Mattle Heinrich P. , Meier Bernhard , Nedeltchev Krassen , Papetti Federica , Di Angelantonio Emanuele , Reisman Mark , Serena Joaquín , Kent David M.
Published: November 2013

Background—

Patent foramen ovale (PFO) is associated with cryptogenic stroke (CS), although the pathogenicity of a discovered PFO in the setting of CS is typically unclear. Transesophageal echocardiography features such as PFO size, associated hypermobile septum, and presence of a right-to-left shunt at rest have all been proposed as markers of risk. The association of these transesophageal echocardiography features with other markers of pathogenicity has not been examined.

Methods and Results—

We used a recently derived score based on clinical and neuroimaging features to stratify patients with PFO and CS by the probability that their stroke is PFO-attributable. We examined whether high-risk transesophageal echocardiography features are seen more frequently in patients more likely to have had a PFO-attributable stroke (n=637) compared with those less likely to have a PFO-attributable stroke (n=657). Large physiologic shunt size was not more frequently seen among those with probable PFO-attributable strokes (odds ratio [OR], 0.92;
P
=0.53). The presence of neither a hypermobile septum nor a right-to-left shunt at rest was detected more often in those with a probable PFO-attributable stroke (OR, 0.80;
P
=0.45; OR, 1.15;
P
=0.11, respectively).

Conclusions—

We found no evidence that the proposed transesophageal echocardiography risk markers of large PFO size, hypermobile septum, and presence of right-to-left shunt at rest are associated with clinical features suggesting that a CS is PFO-attributable. Additional tools to describe PFOs may be useful in helping to determine whether an observed PFO is incidental or pathogenically related to CS.
Evaluation of Vegetation Size and Its Relationship With Embolism in Infective Endocarditis
Authors: Berdejo Javier , Shibayama Kentaro , Harada Kenji , Tanaka Jun , Mihara Hirotsugu , Gurudevan Swaminatha V. , Siegel Robert J. , Shiota Takahiro
Published: November 2013

Background—

Two-dimensional (2D) echocardiography studies have shown that the maximum length of vegetation (MLV) ≥10 mm is a predictor of embolic events (EEs) in patients with infective endocarditis. However, 2D measurements probably underestimate the vegetation dimensions. In this study, we evaluated the feasibility of real-time 3-dimensional transesophageal echocardiography (RT3DTEE) in determining MLV and its accuracy in identifying the risk for EEs compared with 2D transesophageal echocardiography (2DTEE).

Methods and Results—

We analyzed 60 patients with vegetations. RT3DTEE measurement of MLV was obtained with Advanced QLAB Quantification Software by cropping the 3D volume with the appropriate 2D plane to obtain the largest value. The standard 2DTEE images were also evaluated to determine the MLV. Major EEs were registered from medical records, and a logistic regression analysis was performed to determine the association between MLV and EEs. The RT3DTEE MLV was larger than the 2DTEE value with a mean difference of 3.2 mm (95% confidence interval, 2.1–4.2 mm). The best cut-off value for prediction of EEs was MLV ≥20 mm with RT3DTEE and MLV ≥16 mm with 2DTEE. The positive predictive value increased from 59.1% to 65.2% when RT3DTEE was used. The accuracy of classification of patients with EEs increased from 65% to 70% with this new technique.

Conclusions—

RT3DTEE is a feasible technique for the analysis of vegetation morphology and size that may overcome the shortcoming of 2DTEE, leading to a better prediction of the embolism risk in patients with infective endocarditis.
Role of Hemostatic Factors on the Risk of Venous Thrombosis in People With Impaired Kidney Function
Authors: Ocak Gürbey , Vossen Carla Y. , Lijfering Willem M. , Verduijn Marion , Dekker Friedo W. , Rosendaal Frits R. , Cannegieter Suzanne C.
Published: November 2013

Background—

Factors explaining the association between impaired kidney function and venous thrombosis have not been identified so far. The aim of our study was to determine whether the association between impaired kidney function and venous thrombosis can be explained by the concurrent presence of genetic or acquired venous thrombosis risk factors.

Methods and Results—

The glomerular filtration rate was estimated (eGFR) in 2473 venous thrombosis patients and 2936 controls from a population-based case–control study. Kidney function was grouped into 6 categories based on percentiles of the eGFR in the controls (>50th [reference], 10th–50th, 5th–10th, 2.5th–5th, 1st–2.5th, and <1st percentile). Several hemostatic factors showed a procoagulant shift with decreasing kidney function in controls, most notably factor VIII and von Willebrand factor. Compared with eGFR >50th percentile, factor VIII levels (adjusted mean difference, 60 IU/dL for the <1st eGFR percentile category) and von Willebrand factor levels (adjusted mean difference, 60 IU/dL for the <1st eGFR percentile category) increased with each percentile category. The odds ratios for venous thrombosis similarly increased across the categories from 1.1 (95% confidence interval, 0.9–1.3) for the 10th to 50th percentile to 3.7 (95% confidence interval, 2.4–5.7) for the <1st percentile category. Adjustment for factor VIII or von Willebrand factor attenuated these odds ratios, indicating an effect of eGFR on thrombosis through these factors. Adjustments for other risk factors for venous thrombosis did not affect the odds ratios.

Conclusion—

Impaired kidney function affects venous thrombosis risk via concurrently raised factor VIII and von Willebrand factor levels.
Outcomes in Catheter Ablation of Ventricular Tachycardia in Dilated Nonischemic Cardiomyopathy Compared With Ischemic Cardiomyopathy
Authors: Dinov Borislav , Fiedler Lukas , Schönbauer Robert , Bollmann Andreas , Rolf Sascha , Piorkowski Christopher , Hindricks Gerhard , Arya Arash
Published: November 2013

Background—

Data on the outcomes of ventricular tachycardia (VT) ablation in nonischemic dilated cardiomyopathy (NIDCM) are insufficient. The Heart Center of Leipzig VT (HELP-VT) study was conducted prospectively to compare outcomes after radiofrequency catheter ablation of VT in patients with NIDCM compared with ischemic cardiomyopathy (ICM).

Methods and Results—

Two hundred twenty-seven patients, 63 with NIDCM and 164 with ICM, presenting with sustained VT were ablated with radiofrequency catheter ablation. Noninducibility of any clinical and nonclinical VT was achieved in 66.7% of NIDCM and in 77.4% of ICM patients. Ablation of the clinical VT only was achieved in 18.3% of ICM and in 22.2% of NIDCM patients. There was no statistically significant difference in short-term outcomes between the 2 groups. At the 1-year follow-up, VT-free survival in NIDCM was 40.5% compared with 57% in ICM. In univariate analysis, the hazard ratio for VT recurrence was significantly higher for NIDCM (1.62; 95% confidence interval, 1.12– 2.34;
P
=0.01). In both the ICM and NIDCM subgroups, procedure failure and incomplete procedural success were independent predictors of VT recurrence.

Conclusions—

Although the short-term success rates after VT ablation in NIDCM and ICM patients were similar, the long-term outcomes in NIDCM patients were significantly worse. Complete VT noninducibility at the end of the ablation is associated with beneficial long-term outcome in NIDCM. Pursuing compete elimination of all inducible VTs is desirable and may improve the long-term success in NIDCM.
Robust Common Spatial Filters with a Maxmin Approach
Authors: Kawanabe Motoaki , Samek Wojciech , Müller Klaus-Robert , Vidaurre Carmen
Published: November 2013

Electroencephalographic signals are known to be nonstationary and easily affected by artifacts; therefore, their analysis requires methods that can deal with noise. In this work, we present a way to robustify the popular common spatial patterns (CSP) algorithm under a maxmin approach. In contrast to standard CSP that maximizes the variance ratio between two conditions based on a single estimate of the class covariance matrices, we propose to robustly compute spatial filters by maximizing the minimum variance ratio within a prefixed set of covariance matrices called the tolerance set. We show that this kind of maxmin optimization makes CSP robust to outliers and reduces its tendency to overfit. We also present a data-driven approach to construct a tolerance set that captures the variability of the covariance matrices over time and shows its ability to reduce the nonstationarity of the extracted features and significantly improve classification accuracy. We test the spatial filters derived with this approach and compare them to standard CSP and a state-of-the-art method on a real-world brain-computer interface (BCI) data set in which we expect substantial fluctuations caused by environmental differences. Finally we investigate the advantages and limitations of the maxmin approach with simulations.
A New Class of Metrics for Spike Trains
Authors: Rusu Cătălin V. , Florian Răzvan V.
Published: November 2013

The distance between a pair of spike trains, quantifying the differences between them, can be measured using various metrics. Here we introduce a new class of spike train metrics, inspired by the Pompeiu-Hausdorff distance, and compare them with existing metrics. Some of our new metrics (the modulus-metric and the max-metric) have characteristics that are qualitatively different from those of classical metrics like the van Rossum distance or the Victor and Purpura distance. The modulus-metric and the max-metric are particularly suitable for measuring distances between spike trains where information is encoded in bursts, but the number and the timing of spikes inside a burst do not carry information. The modulus-metric does not depend on any parameters and can be computed using a fast algorithm whose time depends linearly on the number of spikes in the two spike trains. We also introduce localized versions of the new metrics, which could have the biologically relevant interpretation of measuring the differences between spike trains as they are perceived at a particular moment in time by a neuron receiving these spike trains.
Improved Sparse Coding Under the Influence of Perceptual Attention
Authors: Amiri Ashkan , Haykin Simon
Published: November 2013

Sparse coding has established itself as a useful tool for the representation of natural data in the neuroscience as well as signal-processing literature. The aim of this letter, inspired by the human brain, is to improve on the performance of the sparse coding algorithm by trying to bridge the gap between neuroscience and engineering. To this end, we build on the localized perception-action cycle in cognitive neuroscience by categorizing it under the umbrella of perceptual attention, which lends itself to increase gradually the contrast between relevant information and irrelevant information. Stated in another way, irrelevant information is filtered away, while relevant information about the environment is enhanced from one cycle to the next. We may thus think in terms of the information filter, which, in a Bayesian context, was introduced in the literature by Fraser ( 1967 ). In a Bayesian context, the information filter provides a method for algorithmic implementation of perceptual attention. The information filter may therefore be viewed as the basis for improving the algorithmic performance of sparse coding. To support this performance improvement, the letter presents two computer experiments. The first experiment uses simulated (real-valued) data that are generated to purposely make the problem challenging. The second uses real-life radar data that are complex valued, hence the proposal to introduce Wirtinger calculus into derivation of the new algorithm.
Spontaneous Clustering via Minimum Gamma-Divergence
Authors: Notsu Akifumi , Komori Osamu , Eguchi Shinto
Published: November 2013

We propose a new method for clustering based on local minimization of the gamma-divergence, which we call spontaneous clustering. The greatest advantage of the proposed method is that it automatically detects the number of clusters that adequately reflect the data structure. In contrast, existing methods, such as K-means, fuzzy c-means, or model-based clustering need to prescribe the number of clusters. We detect all the local minimum points of the gamma-divergence, by which we define the cluster centers. A necessary and sufficient condition for the gamma-divergence to have local minimum points is also derived in a simple setting. Applications to simulated and real data are presented to compare the proposed method with existing ones.
Likelihood Methods for Point Processes with Refractoriness
Authors: Citi Luca , Ba Demba , Brown Emery N. , Barbieri Riccardo
Published: November 2013

Likelihood-based encoding models founded on point processes have received significant attention in the literature because of their ability to reveal the information encoded by spiking neural populations. We propose an approximation to the likelihood of a point-process model of neurons that holds under assumptions about the continuous time process that are physiologically reasonable for neural spike trains: the presence of a refractory period, the predictability of the conditional intensity function, and its integrability. These are properties that apply to a large class of point processes arising in applications other than neuroscience. The proposed approach has several advantages over conventional ones. In particular, one can use standard fitting procedures for generalized linear models based on iteratively reweighted least squares while improving the accuracy of the approximation to the likelihood and reducing bias in the estimation of the parameters of the underlying continuous-time model. As a result, the proposed approach can use a larger bin size to achieve the same accuracy as conventional approaches would with a smaller bin size. This is particularly important when analyzing neural data with high mean and instantaneous firing rates. We demonstrate these claims on simulated and real neural spiking activity. By allowing a substantive increase in the required bin size, our algorithm has the potential to lower the barrier to the use of point-process methods in an increasing number of applications.
Begonia tandangii (Begoniaceae, section Baryandra), a new species from Luzon Island, the Philippines
Authors: Nakamura Koh , Rubite Rosario Rivera , Kono Yoshiko , Callado John Rey , Peng Ching-I
Published: November 2013

We describe Begonia tandangii, a new species of Begonia sect. Baryandra from the Sierra Madre Mountain Range of Luzon Island, the Philippines. Begonia tandangii has a close resemblance to B. fenicis in gross morphology, differing in having leaf margin sparsely fringed with minute hairs (vs. glabrous or with minute hairs only on teeth) and capsules with broadly-ovate outline and an acuminate apex (vs. capsules with broadly-obovate outline and a rounded to truncate apex). Phylogenetic analyses of Philippines species of sect. Baryandra based on ITS sequences revealed that B. tandangii was clearly separated from B. fenicis. Begonia tandangii is currently known only from the type locality in a coastal forest of Baler, Aurora Province, which is in the neighborhood of Aurora Memorial National Park.
Toward an Understanding of the Emotional and Behavioral Reactions to Stalking
Authors: Ngo Fawn T. , Paternoster Raymond
Published: November 2013

Using data from the Supplemental Victimization Survey and relying on theoretical direction provided by Agnew’s general strain theory, we examine whether specific types of stalking experiences trigger specific types of negative emotional states and whether specific negative emotional states are in turn associated with specific types of noncriminal coping mechanisms. We find that while several of the stalking experiences trigger a variety of negative emotional states, other stalking experiences do not exhibit any association with negative emotions. We also uncover that negative emotional states in response to strain can trigger legitimate coping mechanisms. One notable finding that emerged from our results is that feeling annoyed/angry is significantly associated with noncriminal coping strategies. The policy implications of our findings are also discussed.
Internal Migration and Citizenship Education in China’s Shenzhen City
Authors: Ye Wangbei
Published: November 2013

Migration’s influences on citizenship education were widely discussed in the literature. However, most studies were based on international migration that drew experience from, for example, North America and Europe. Less attention was paid to internal migration or developing areas. This article takes China as an example, which is a country that has experienced and will experience extensive internal migration, to analyze the relationship between internal migration and citizenship education. This article selects Shenzhen as a study site, for it reflects China’s population movements and city development in the last three decades. Interviews with 38 teachers in six schools and relevant university scholars, education bureau officers in 2008 were analyzed for this article. The article reports Shenzhen citizenship education’s responses to three challenges brought by internal migration. The analyses of the findings reveal that different from assimilation and multiculturalism approaches in citizenship education, Shenzhen’s citizenship education paid less efforts to diminish/reconcile migrants’ ethnic, cultural differences. Instead, it inclined to address the general problems caused by the migration phenomenon. Similarly, it also laid efforts on migrant integration and social cohesion.
Biomechanical and Performance Implications of Weapon Design
Authors: Stone Richard T. , Moeller Brandon F. , Mayer Robert R. , Rosenquist Bryce , Van Ryswyk Darin , Eichorn Drew
Published: November 2013

Objective:

Shooter accuracy and stability were monitored while firing two bullpup and two conventional configuration rifles of the same caliber in order to determine if one style of weapon results in superior performance.

Background:

Considerable debate exists among police and military professionals regarding the differences between conventional configuration weapons, where the magazine and action are located ahead of the trigger, and bullpup configuration, where they are located behind the trigger (closer to the user). To date, no published research has attempted to evaluate this question from a physical ergonomics standpoint, and the knowledge that one style might improve stability or result in superior performance is of interest to countless military, law enforcement, and industry experts.

Method:

A live-fire evaluation of both weapon styles was performed using a total of 48 participants. Shooting accuracy and fluctuations in biomechanical stability (center of pressure) were monitored while subjects used the weapons to perform standard drills.

Results:

The bullpup weapon designs were found to provide a significant advantage in accuracy and shooter stability, while subjects showed considerable preference toward the conventional weapons.

Conclusion:

Although many mechanical and maintenance issues must be considered before committing to a bullpup or conventional weapon system, it is clear in terms of basic human stability that the bullpup is the more advantageous configuration.

Application:

Results can be used by competitive shooter, military, law enforcement, and industry experts while outfitting personnel with a weapon system that leads to superior performance.
Does respect for human rights vary across ‘civilizations’? A statistical reexamination
Authors: Cole Wade M
Published: November 2013

The cultural content of international human rights standards has inspired much discussion and debate, but cross-cultural levels of compliance with these standards remains understudied. Using Samuel Huntington’s controversial ‘clash-of-civilizations’ thesis as a point of departure, this article analyzes whether human rights practices differ systematically across dominant cultural and religious traditions, with a focus on two sets of rights: bodily integrity and civil/political. Net of standard political, social, economic, and demographic factors, countries identified as Western countries and Japan generally have better rated practices than other countries, but differences are especially pronounced with respect to Buddhist, Catholic/Latin, Islamic, and Orthodox nations. These countries are closely scrutinized by watchdogs such as Amnesty International, which might account for their lower human rights scores. Variation in human rights scores also tends to be durable over time; in contrast with Huntington’s thesis, the end of the Cold War mattered little for cross-cultural differences in countries’ practices. Finally, cultural and religious effects are more pronounced for bodily integrity rights than for civil and political rights. All told, the analyses offer little support for the clash-of-civilizations approach, insofar as it predicts increased cultural conflict over putatively ‘Western’ human rights standards.
Opposite Ends of the Same Stick? Multi-Method Test of the Dimensionality of Individualism and Collectivism
Authors: Taras Vas , Sarala Riikka , Muchinsky Paul , Kemmelmeier Markus , Singelis Theodore M. , Avsec Andreja , Coon Heather M. , Dinnel Dale L. , Gardner Wendi , Grace Sherry , Hardin Erin E. , Hsu Sandy , Johnson Joel , Karakitapoğlu Aygün Zahide , Kashima Emiko S. , Kolstad Arnulf , Milfont Taciano L. , Oetzel John , Okazaki Sumie , Probst Tahira M. , Sato Toru , Shafiro Maggie , Schwartz Seth J. , Sinclair H. Colleen
Published: November 2013

The construct of individualism–collectivism (IND-COL) has become the definitive standard in cross-cultural psychology, management, and related fields. It is also among the most controversial, in particular, with regard to the ambiguity of its dimensionality: Some view IND and COL as the opposites of a single continuum, whereas others argue that the two are independent constructs. We explored the issue through seven different tests using original individual-level data from 50 studies and meta-analytic data from 149 empirical publications yielding a total of 295 sample-level observations that were collected using six established instruments for assessing IND and COL as separate constructs. Results indicated that the dimensionality of IND-COL may depend on (a) the specific instrument used to collect the data, (b) the sample characteristics and the cultural region from which the data were collected, and (c) the level of analysis. We also review inconsistencies, deficiencies, and challenges of conceptualizing IND-COL and provide guidelines for developing and selecting instruments for measuring the construct, and for reporting and meta-analyzing results from this line of research.
The Connections Between Substance Dependence, Offense Type, and Offense Severity
Authors: Kopak Albert M. , Vartanian Lisa , Hoffmann Norman G. , Hunt Dana E.
Published: November 2013

The link between drug use and crime has been broadly described, but little detail is known about the contributions of alcohol and drug dependence to different types of offending. Data were drawn from the 2010 Arrestee Drug Abuse Monitoring II (ADAM II) program to examine the relationships between dependence, offense type, and severity among recent male arrestees ( N = 3,006). A substantial proportion (ranging from 15% to 39%) of arrestees across all offense types and severity levels endorsed drug-dependent items. Smaller proportions (between 5% and 16%) of arrestees endorsed alcohol-dependent items. Drug dependence was associated with higher odds of receiving felony charges and higher probability of being charged with a substance-related offense. Alcohol dependence was associated with lower odds of felony charges, but greater probability of being charged with a violent offense. Assessment and treatment provisions need to be systematically implemented to reduce these types of offenses.
Structures and properties of polyphosphoric acid/acetic acid functionalized HMPBO fibres
Authors: Wang Jieliang , Pan Xiaochun , Zhang Wulong , Hu Zhiyi
Published: November 2013

The surfaces of high-modulus poly ( p-phenylene-2, 6-benzobisoxazole) (HMPBO) fibres have been treated by a solution of polyphosphoric acid/acetic acid (PPA/AA). The single fibre pull-out strength, chemical compositions and surface morphologies of HMPBO fibres were tested and characterized by single fibre pull-out tests, contact angles, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscopy and thermogravimetric analyzer. Results show that this method has great potential in the surface treatment of HMPBO fibres.
Control of non-linear non-integer-order systems using variable structure control theory
Authors: Aghababa Mohammad Pourmahmood
Published: November 2013

This paper deals with the problem of robust control of uncertain non-integer-order non-linear complex systems in finite time. First, a novel fractional-order integral-type switching manifold is introduced. Then, the fractional-order stability theory is used to prove the finite time stability of the resulting sliding mode dynamics in a given finite time. Afterward, using the variable structure control theory, a novel robust non-integer control law is proposed to guarantee the convergence of the system trajectories to the prescribed sliding manifold within a given finite time. Simulation results reveal that the proposed fractional variable structure controller works well for finite-time chaos suppression of fractional-order hyperchaotic Chen and chaotic Lorenz systems with system uncertainties.
A combination forecast method based on cross entropy theory for wind power and application in power control
Authors: Tang Yi , Qi Wang , Sha Qian , Chen Ning , Zhu Lingzhi
Published: November 2013

Predication of large-scale grid-connected wind power is important for a power system operation’s stability and security. To avoid the problem of being excessively dependent on reference samples, cross entropy theory-based information fusion technology is utilized to set up a new combination predication model for wind power prediction. In this new model, wind power prediction is regarded as an information fusion problem, and the weights of each predication method are dynamically determined by the cross degree of prediction methods obtained by cross entropy theory. The case studies of a practical wind farm validate the effectiveness and correctness of the proposed method to predict wind power and the design of the power dispatching scheme.