bluuebunny/crossref_metadata_2025_split huggingface dataset:
A model of carbon evasion and sedimentation in temperate lakes
Authors: Hanson Paul C. , Pollard Amina I. , Bade Darren L. , Predick Katie , Carpenter Stephen R. , Foley Jonathan A. 
Published: November 2008

AbstractLakes process terrigenous carbon. The carbon load processed by lakes may partially offset estimates made for terrestrial net ecosystem exchange (NEE). The balance within lakes between carbon burial and evasion to the atmosphere determines whether lakes are net sinks or net sources of atmospheric carbon. Here we develop a model to study processing of both autochthonous and allochthonous carbon sources in lakes. We run the model over gradients of dissolved organic carbon (DOC) and total phosphorus (TP) concentrations found in the Northern Highlands Lake District of Wisconsin. In our model, lakes processed between 5 and 28 g C m−2  (watershed)  yr−1 derived from the watershed, which approximates one‐tenth of NEE for similar terrestrial systems without lakes. Most lakes were net heterotrophic and had carbon evasion in excess of carbon burial, making them net sources of carbon to the atmosphere. Only lakes low in DOC and moderate to high in TP were net autotrophic and net sinks of carbon from the atmosphere.
Corporate Carbon Performance Indicators
Authors: Hoffmann Volker H. , Busch Timo 
Published: November 2008

SummaryThe dependency on carbon‐based materials and energy sources and the emission of greenhouse gases have been recognized as major problems of the 21st century. Companies are central to the effort to grapple with these issues due to the large material flows they process and their capabilities for technological innovation. It is important, on the one hand, to determine the individual stake companies have in these issues and, on the other, to measure companies' performance. Since the results of studies thus far have been ambiguous, we define four comprehensive and systematic corporate carbon performance indicators: (1) Carbon intensity is physically oriented and represents a company's carbon use in relation to a business metric. (2) Carbon dependency illustrates the change in physical carbon performance within a given time period. (3) Carbon exposure reveals the financial implications of using and emitting carbon. (4) Carbon risk estimates the change in financial implications of carbon usage within a given time period. On the basis of these general definitions, we specify the indicators for a standardized application that can support two important stakeholders in their decision making: policy makers, who can include such information when evaluating current climate policies and formulating future ones, and investors and financial institutions, which can compare companies with respect to their carbon performance and corresponding financial effects.
Mandatory Disclosure and Operational Risk: Evidence from Hedge Fund Registration
Authors: BROWN STEPHEN , GOETZMANN WILLIAM , LIANG BING , SCHWARZ CHRISTOPHER 
Published: November 2008

ABSTRACTMandatory disclosure is a regulatory tool intended to allow market participants to assess operational risk. We examine the value of disclosure through the controversial SEC requirement, since overturned, which required major hedge funds to register as investment advisors and file Form ADV disclosures. Leverage and ownership structures suggest that lenders and equity investors were already aware of operational risk. However, operational risk does not mediate flow‐performance relationships. Investors either lack this information or regard it as immaterial. These findings suggest that regulators should account for the endogenous production of information and the marginal benefit of disclosure to different investment clienteles.
The Geography of Block Acquisitions
Authors: KANG JUN‐KOO , KIM JIN‐MO 
Published: November 2008

ABSTRACTUsing a large sample of partial block acquisitions, we examine the importance of geographic proximity in corporate governance and target returns. We find that block acquirers have a strong preference for geographically proximate targets and acquirers that purchase shares in such targets are more likely to engage in post‐acquisition target governance activities than are remote block acquirers. Moreover, the targets of these acquirers realize higher announcement returns and better post‐acquisition operating performance than do targets of other types of acquirers, particularly when they face greater information asymmetries.
How Does Size Affect Mutual Fund Behavior?
Authors: POLLET JOSHUA M. , WILSON MUNGO 
Published: November 2008

ABSTRACTIf actively managed mutual funds suffer from diminishing returns to scale, funds should alter investment behavior as assets under management increase. Although asset growth has little effect on the behavior of the typical fund, we find that large funds and small‐cap funds diversify their portfolios in response to growth. Greater diversification, especially for small‐cap funds, is associated with better performance. Fund family growth is related to the introduction of new funds that hold different stocks from their existing siblings. Funds with many siblings diversify less rapidly as they grow, suggesting that the fund family may influence a fund's portfolio strategy.
Average Returns, B/M, and Share Issues
Authors: FAMA EUGENE F. , FRENCH KENNETH R. 
Published: November 2008

ABSTRACTThe book‐to‐market ratio (B/M) is a noisy measure of expected stock returns because it also varies with expected cashflows. Our hypothesis is that the evolution of B/M, in terms of past changes in book equity and price, contains independent information about expected cashflows that can be used to improve estimates of expected returns. The tests support this hypothesis, with results that are largely but not entirely similar for Microcap stocks (below the 20th NYSE market capitalization percentile) and All but Micro stocks (ABM).
Limited Attention and the Allocation of Effort in Securities Trading
Authors: CORWIN SHANE A. , COUGHENOUR JAY F. 
Published: November 2008

ABSTRACTWhile limited attention has been analyzed in a variety of economic and psychological settings, its impact on financial markets is not well understood. In this paper, we examine individual NYSE specialist portfolios and test whether liquidity provision is affected as specialists allocate their attention across stocks. Our results indicate that specialists allocate effort toward their most active stocks during periods of increased activity, resulting in less frequent price improvement and increased transaction costs for their remaining assigned stocks. Thus, the allocation of effort due to limited attention has a significant impact on liquidity provision in securities markets.
The ECG Lead I Paradox in Cardiac Resynchronization Therapy
Authors: VAN GELDER BERRY M. , BRACKE FRANK A. 
Published: November 2008

Background: In cardiac resynchronization therapy (CRT), the morphology of the QRS complex plays an important role in the determination of the pacing site and effectiveness of stimulation.
Patients and Methods: Review of the electrocardiograms (ECGs) of 737 patients with a CRT device showed a negative QRS complex in lead I during right ventricular (RV) pacing and a positive QRS complex during left ventricular (LV) pacing in four patients. The RV lead was positioned in the high RV septum and the coronary sinus leads in a posterior or postero‐lateral basal level. Reversed ECG lead or pacemaker lead connection, anodal RV stimulation, and scar tissue‐related depolarization abnormalities were excluded as possible causes.
Conclusion: Pacing from the high RV septum may rarely lead to a negative QRS complex and basal positions of the LV lead to a positive QRS complex in lead I during LV pacing. The lead I paradox becomes obvious when both phenomena, that are not interrelated, are present in the same patient.
Age‐Specific Differences in Women with Implantable Cardioverter Defibrillators: An International Multi Center Study
Authors: VAZQUEZ LAUREN D. , KUHL EMILY A. , SHEA JULIE BISHOP , KIRKNESS ANN , LEMON JIM , WHALLEY DAVID , CONTI JAMIE B. , SEARS SAMUEL F. 
Published: November 2008

Background: Common psychological adjustment difficulties have been identified for groups of implantable cardioverter defibrillator patients, such as those who are young (<50 years old), have been shocked, and are female. Specific aspects and concerns, such as fears of death or shock and body image concerns, that increase the chance of distress, have not been examined in different aged female implantable cardioverter defibrillator (ICD) recipients. The aim of the study was to investigate these areas of adjustment across three age groups of women from multiple centers.
Methods: Eighty‐eight female ICD patients were recruited at three medical centers: Shands Hospital at the University of Florida, Brigham and Women's Hospital in Boston, and Royal North Shore Hospital in Sydney, Australia. Women completed individual psychological assessment batteries, measuring the constructs of shock anxiety, death anxiety, and body image concerns. Medical record review was conducted for all patients regarding cardiac illnesses and ICD‐specific data.
Results: Multivariate and univariate analyses of variance revealed that younger women reported significantly higher rates of shock and death anxiety (Pillai's F = 3.053, P = 0.018, η2p= 0.067) and significantly greater body image concerns (Pillai's F = 4.198, P = 0.018, η2p= 0.090) than middle‐ and older‐aged women.
Conclusions: Women under the age of 50 appear to be at greater risk for the development of psychosocial distress associated with shock anxiety, death anxiety, and body image. Clinical‐based strategies and interventions targeting these types of adjustment difficulties in younger women may allow for improved psychosocial and quality of life outcomes.
Analysis during Sinus Rhythm and Ventricular Pacing of Reentry Circuit Isthmus Sites in Right Ventricular Cardiomyopathy
Authors: REITHMANN CHRISTOPHER , ULBRICH MICHAEL , HAHNEFELD ANTON , HUBER ARMIN , MATIS TOMAS , STEINBECK GERHARD 
Published: November 2008

Background: The entrainment mapping algorithm is used for ablation of ventricular tachycardia (VT) in right ventricular (RV) cardiomyopathy, but ablation at endocardial isthmus sites has only a moderate success rate. This study was performed to identify additional local electrogram characteristics associated with successful ablation.
Patients and Methods: Using entrainment mapping, 45 reentry circuit isthmus sites were detected in 11 patients with RV cardiomyopathy presenting with 13 monomorphic VTs. Local bipolar electrograms were retrospectively analyzed at reentry circuit isthmus sites during VT, sinus rhythm, and programmed stimulation from the right ventricular apex (RVA), and compared between successful and unsuccessful ablation sites.
Results: Ablation was successful at 10 reentry circuit isthmus sites and unsuccessful at 35 isthmus sites. During VT, a longer endocardial activation time relative to QRS onset, an increased electrogram‐QRS interval as a percentage of VT cycle length, and a longer electrogram duration were found at successful in comparison to unsuccessful ablation sites. The presence of isolated diastolic potentials during sinus rhythm at reentry circuit isthmus sites, consistent with slow conduction or unidirectional conduction block, was associated with successful catheter ablation. Prolongation of the duration of the local multipotential electrogram by >100 ms during programmed RVA pacing at reentry circuit exit sites, indicating functional conduction disorder was also a marker of successful ablation.
Conclusions: The demonstration of multipotential electrogram characteristics indicating fixed or functional conduction block may increase the likelihood of successful VT ablation at exit and central isthmus sites of reentry circuits in RV cardiomyopathy.
Experimental Measures of Ventricular Activation and Synchrony
Authors: SUTHERLAND DAVID R. , NI QUAN , MacLEOD ROB S. , LUX ROBERT L. , PUNSKE BONNIE B. 
Published: November 2008

Background:A widened QRS complex as a primary indication for cardiac resynchronization therapy (CRT) for heart failure patients has been reported to be an inconsistent indicator for dyssynchronous ventricular activation. The purpose of this study was to conduct a detailed experimental investigation of total ventricular activation time (TVAT), determine how to measure it accurately, and compare it to the commonly used measure of QRS width. In addition, we investigated a measure of electrical synchrony and determined its relationship to the duration of ventricular activation.Methods:Unipolar electrograms (EGs) were recorded from the myocardial volume using plunge needle electrodes, from the epicardial surface using “sock” electrode arrays, and from the surface of an electrolytic torso‐shaped tank. EGs were analyzed to determine a root mean square (RMS)‐based measure of ventricular activation and electrical ventricular synchrony.Results:The RMS‐based technique provided an accurate means of measuring TVAT from unipolar EGs recorded from the heart, the entire tank surface, or the precordial leads. In normal canine hearts, a quantification of ventricular electrical synchrony (VES) for normal ventricular activation showed that the ventricles activate, on average, within 3 ms of each other with the left typically activating first.Conclusion:Conclusions from this study are: (1) ventricular activation was reflected accurately by the RMS width obtained from direct cardiac measurements and from precordial leads on the tank surface and (2) VES was not strongly correlated with TVAT.
Long‐term Follow‐up of P‐wave Duration and Dispersion in Patients with Mitral Stenosis
Authors: GUNTEKIN UNAL , GUNES YILMAZ , TUNCER MUSTAFA , GUNES AHMET , SAHIN MUSA , SIMSEK HAKKI 
Published: November 2008

Background: Patients with mitral stenosis have prolonged P‐wave duration and increased P‐wave dispersion (PWD) that have been associated with increased risk for atrial fibrillation.
Methods: Thirty mild‐to‐moderate mitral stenosis patients were followed for 38.4 ± 10.7 (23–48) months. Baseline and last 12‐lead electrocardiographic and transthoracic echocardiographic measurements were evaluated. Maximum and minimum P‐wave durations (Pmax and Pmin) and PWD were calculated.
Results: Pmax and PWD were significantly higher in patients compared to control group. Left atrial (LA) size, mitral gradient, and pulmonary artery systolic pressure (PASP) were significantly increased and mitral valve area (MVA) was decreased during follow‐up. There were significant increases in Pmax and PWD and significant decrease in Pmin (Pmax: 101.0 ± 12.5 ms vs 105.0 ± 16.5 ms, P = 0.005; Pmin: 59.3 ± 8.5 ms vs 55.0 ± 12.3 ms P = 0.004; PWD: 41.7 ± 5.5 ms vs 50.0 ± 6.2 ms, P < 0.001). Baseline Pmax, Pmin, and PWD were significantly correlated with MVA (Pmax: r =−0.605, P < 0.001, Pmin: r =−0.632, P < 0.001, PWD: r =−0.402, P = 0.0028) and mean mitral gradient (Pmax: r = 0.412, P = 0.024, Pmin: r = 0.632, P = 0.049, PWD: r = 0.378, P = 0.039). In addition to MVA and mean mitral gradient follow‐up P‐wave variables were significantly correlated with LA size (Pmax: r = 0.573, P = 0.001, Pmin: r = 0.636, P = 0.001, PWD: r = 0.265, P = 0.046) and PASP (Pmax: r = 0.462, P = 0.011, Pmin: r = 0.472, P = 0.008 PWD: r = 0.295, P = 0.047).
Conclusions: P‐wave duration and PWD increase progressively in accordance with the progression of mitral stenosis.
Prospective Study of Cardiac Sarcoid Mimicking Arrhythmogenic Right Ventricular Dysplasia
Authors: VASAIWALA SMIT C. , FINN CYNTHIA , DELPRIORE JEANNE , LEYA FRED , GAGERMEIER JAMES , AKAR JOSEPH G. , SANTUCCI PETER , DAJANI KHALED , BOVA DAVIDE , PICKEN MARIA M. , BASSO CRISTINA , MARCUS FRANK , WILBER DAVID J. 
Published: November 2008

Introduction:
Case studies indicate that cardiac sarcoid may mimic the clinical presentation of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C); however, the incidence and clinical predictors to diagnose cardiac sarcoid in patients who meet International Task Force criteria for ARVD/C are unknown.
Methods and Results:
Patients referred for evaluation of left bundle branch block (LBBB)‐type ventricular arrhythmia and suspected ARVD/C were prospectively evaluated by a standardized protocol including right ventricle (RV) cineangiography‐guided myocardial biopsy. Sixteen patients had definite ARVD/C and four had probable ARVD/C. Three patients were found to have noncaseating granulomas on biopsy consistent with sarcoid. Age, systemic symptoms, findings on chest X‐ray or magnetic resonance imaging (MRI), type of ventricular arrhythmia, RV function, ECG abnormalities, and the presence or duration of late potentials did not discriminate between sarcoid and ARVD/C. Left ventricular dysfunction (ejection fraction <50%) was present in 3/3 patients with cardiac sarcoid, but only 2/17 remaining patients with definite or probable ARVD/C (P = 0.01).
Conclusions:
In this prospective study of consecutive patients with suspected ARVD/C evaluated by a standard protocol including biopsy, the incidence of cardiac sarcoid was surprisingly high (15%). Clinical features, with the exception of left ventricular dysfunction and histological findings, did not discriminate between the two entities.
Predicting Recurrence of Vasovagal Syncope: A Simple Risk Score for the Clinical Routine
Authors: AYDIN MUHAMMET A. , MAAS RENKE , MORTENSEN KAI , STEINIG TOBIAS , KLEMM HANNO , RISIUS TIM , MEINERTZ THOMAS , WILLEMS STEPHAN , MORILLO CARLOS A. , VENTURA RODOLFO 
Published: November 2008

Background:
Predictors for recurrence of syncope are lacking in patients with vasovagal syncope. The aim of this study was to identify risk factors for recurrence of syncope and develop a simple prognostic risk score of clinical value.
Methods:
Two hundred seventy‐six patients with a history of vasovagal syncope were prospectively followed for 2 years. Diagnosis of vasovagal syncope was based on clinical history and negative standard work‐up. Inclusion in the study was independent from the result of the head‐up tilt test, which was performed in all cases. Risk factors for syncope recurrence were evaluated by the Cox proportional hazards regression model and implemented in a risk score, which was validated with the log‐rank test and an internal cross‐validation.
Results:
The Cox‐regression analysis identified the number of previous syncopal events, history of bronchial asthma, and female gender as predictors for syncope recurrence (all P < 0.05). In contrast, head‐up tilt test response had no predictive value (P = 0.881). Developing a risk score, study patients were identified as having high (recurrence rate during 2 years of follow‐up: 37.2%), intermediate (24.8%), and low (6.5%) risk for syncope recurrence (receiver operating characteristic [ROC] of score 0.83, P < 0.01; Log‐rank test for event‐free survival, P < 0.005).
Conclusions:
In patients with vasovagal syncope, risk of recurrence can be stratified and is predictable based on a simple risk score.
Relationship Between Catheter Forces, Lesion Characteristics, “Popping,” and Char Formation: Experience with Robotic Navigation System
Authors: DI BIASE LUIGI , NATALE ANDREA , BARRETT CONOR , TAN CARMELA , ELAYI CLAUDE S. , CHING CHI KEONG , WANG PAUL , AL‐AHMAD AMIN , ARRUDA MAURICIO , BURKHARDT J. DAVID , WISNOSKEY BRIAN J. , CHOWDHURY PUNAM , DE MARCO SHARI , ARMAGANIJAN LUCIANA , LITWAK KENNETH N. , SCHWEIKERT ROBERT A. , CUMMINGS JENNIFER E. 
Published: November 2008

Introduction:
Popping, char and perforation are complications that can occur following catheter ablation. We measured the amount of grams (g) applied to the endocardium during ablation using a sensor incorporated in the long sheath of a robotic system. We evaluated the relationship between lesion formation, pressure, and the development of complications.
Methods:
Using a robotic navigation system, lesions were placed in the left atrium (LA) at six settings, using a constant duration (40 seconds) and flow rate of either 17 cc/min or 30 cc/min with an open irrigated catheter (OIC). Evidence of complications was noted and lesion location recorded for later analysis at necropsy.
Results:
Lesions using 30 Watts (W) were more likely to be transmural at higher (>40 g) than lower (<30 g) pressures (75% vs 25%, P < 0.001). Significantly higher number of lesions using >40 g of pressure demonstrated “popping” and crater formation as compared with lesions with 20–30 g of pressure (41% vs 15%, P = 0.008). A majority of lesions placed using higher power (45 W) with higher pressures (>40 g) were associated with char and crater formation (66.7%). No lesions using 10 g of pressure were transmural, regardless of the power. Lesions placed with a power setting less than 35 W were more likely to result in “relative” sparing of the endocardial surface than lesions at a power setting higher than 35 W (62% vs 33.3%, P = 0.02) regardless of the pressure.
Conclusions:
When using an OIC, lower power settings (≤35 W) and lower/medium contact pressure were more likely to show a “relative” spared endocardial surface. Overall, contact pressure between 20 g and 30 g and a power setting of 40 W appeared to achieve transmurality by preserving safety.
Severity of personality disorders and suicide attempt
Authors: Blasco‐Fontecilla H. , Baca‐Garcia E. , Dervic K. , Perez‐Rodriguez M. M. , Saiz‐Gonzalez M. D. , Saiz‐Ruiz J. , Oquendo M. A. , De Leon J. 
Published: November 2008

Objective:  Severity of personality disorders (PDs) may be more useful in estimating suicide risk than the diagnosis of specific PDs. We hypothesized that suicide attempters with severe PD would present more attempts and attempts of greater severity/lethality.Method:  Four hundred and forty‐six suicide attempters were assessed. PD diagnosis was made using the International Personality Disorder Questionnaire – Screening Questionnaire. PDs were classified using Tyrer and Johnson’s classification of severity (no PD, simple PD, diffuse PD). Severity/lethality of attempts was measured with the Suicide Intent Scale, Risk‐Rescue Rating Scale and Lethality Rating Scale.Results:  Attempters with severe (diffuse) PD had more attempts than the other groups. After controlling for age and gender, this difference remained significant only for the younger age group and women. There was no relationship between severity of PDs and severity/lethality of attempts.Conclusion:  Younger female attempters with severe PD are prone to repeated attempts. However, the severity of PD was not related to the severity/lethality of suicide attempts.