bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analyzing the Tax Benefits from Employee Stock Options
Authors: BABENKO ILONA , TSERLUKEVICH YURI 
Published: July 2009

ABSTRACTEmployees tend to exercise stock options when corporate taxable income is high, shifting corporate tax deductions to years with higher tax rates. If firms paid employees the same dollar value in wages instead of stock options, the average annual tax bill for large U.S. companies would increase by $12.6 million, or 9.8%. These direct tax benefits of options increase in the convexity of the tax function. In addition, profitable firms can realize indirect tax benefits because stock options increase debt capacity. Although tax minimization is probably not the main motive for option grants, firms with larger potential tax benefits grant more options.
Rewriting History
Authors: LJUNGQVIST ALEXANDER , MALLOY CHRISTOPHER , MARSTON FELICIA 
Published: July 2009

ABSTRACTWe document widespread changes to the historical I/B/E/S analyst stock recommendations database. Across seven I/B/E/S downloads, obtained between 2000 and 2007, we find that between 6,580 (1.6%) and 97,582 (21.7%) of matched observations are different from one download to the next. The changes include alterations of recommendations, additions and deletions of records, and removal of analyst names. These changes are nonrandom, clustering by analyst reputation, broker size and status, and recommendation boldness, and affect trading signal classifications and back‐tests of three stylized facts: profitability of trading signals, profitability of consensus recommendation changes, and persistence in individual analyst stock‐picking ability.
Limitations of Dower's Inverse Transform for the Study of Atrial Loops during Atrial Fibrillation
Authors: GUILLEM MARÍA S. , CLIMENT ANDREU M. , BOLLMANN ANDREAS , HUSSER DANIELA , MILLET JOSÉ , CASTELLS FRANCISCO 
Published: July 2009

Introduction: Spatial characteristics of atrial fibrillatory waves have been extracted by using a vectorcardiogram (VCG) during atrial fibrillation (AF). However, the VCG is usually not recorded in clinical practice and atrial loops are derived from the 12‐lead electrocardiogram (ECG). We evaluated the suitability of the reconstruction of orthogonal leads from the 12‐lead ECG for fibrillatory waves in AF.
Methods: We used the Physikalisch‐Technische Bundesanstalt diagnostic ECG database, which contains 15 simultaneously recorded signals (12‐lead ECG and three Frank orthogonal leads) of 13 patients during AF. Frank leads were derived from the 12‐lead ECG by using Dower's inverse transform. Derived leads were then compared to true Frank leads in terms of the relative error achieved. We calculated the orientation of AF loops of both recorded orthogonal leads and derived leads and measured the difference in estimated orientation. Also, we investigated the relationship of errors in derivation with fibrillatory wave amplitude, frequency, wave residuum, and fit to a plane of the AF loops.
Results: Errors in derivation of AF loops were 68 ± 31% and errors in the estimation of orientation were 35.85 ± 20.43°. We did not find any correlation among these errors and amplitude, frequency, or other parameters.
Conclusions: In conclusion, Dower's inverse transform should not be used for the derivation of orthogonal leads from the 12‐lead ECG for the analysis of fibrillatory wave loops in AF. Spatial parameters obtained after this derivation may differ from those obtained from recorded orthogonal leads.
Atrial Fibrillation Significantly Increases Total Mortality and Stroke Risk Beyond that Conveyed by the CHADS2 Risk Factors
Authors: CRANDALL MARK A. , HORNE BENJAMIN D. , DAY JOHN D. , ANDERSON JEFFREY L. , MUHLESTEIN JOSEPH B. , CRANDALL BRIAN G. , WEISS J. PETER , OSBORNE JEFFREY S. , LAPPÉ DONALD L. , BUNCH T. JARED 
Published: July 2009

Background: Atrial fibrillation (AF) is associated with an increased risk of mortality and stroke. However, it is unclear if AF is independently associated with these poor outcomes or it is merely a risk marker of other processes that convey the risk.
Methods: Consecutive patients who underwent angiography for suspicion of coronary artery disease, but without a history of AF, were studied. Traditional CHADS2 (congestive heart failure, hypertension, age >75 years, diabetes, stroke/transient ischemic attack) risk factors for each patient were recorded.
Results: A total of 343 AF patients (age = 69 ± 10 years, 215 [63%] male) and 2,945 non‐AF patients (age = 63 ± 12 years, 2,012 [67%] male) were studied. Among AF patients, 51 (15%) had a myocardial infarction (MI), 35 (10%) had a stroke, and 180 (52%) died. CHADS2 score incrementally increased risk of stroke (adjusted hazard ratio [HR] for 1:1.92, 2:2.30, 3:1.14, 4:3.83, 5:10.96; P‐trend = 0.14), death (HR for 1:1.83, 2:2.34, 3:3.69, 4:2.27, 5:4.53; P‐trend < 0.001), and major adverse cardiac event (MACE)
(HR for 1:1.29, 2:1.54, 3:2.07, 4:2.41, 5:2.68; P‐trend = 0.002). Among non‐AF patients, CHADS2 score incrementally increased risk of stroke (HR for 1:1.18, 2:3.17, 3:5.08, 4:10.78, 5:7.50; P‐trend < 0.001), MI (HR for 1:1.05, 2:1.46, 3:1.57, 4:0.53, 5:4.76; P‐trend = 0.002), death (HR for 1:1.79, 2:3.22, 3:6.23, 4:9.09, 5:14.00; P‐trend < 0.001), and MACE (HR for 1:1.47, 2:2.36, 3:4.16, 4:5.91, 5:7.56; P‐trend < 0.001). Among all patients, both CHADS2 score (all P ≤ 0.001) and AF were independent risk factors for stroke (AF: P = 0.002), MI (AF: P = 0.035), death (AF: P < 0.001), and MACE (AF: P < 0.001).
Conclusion: The CHADS2 score is a powerful predictor of stroke and death. AF increases the risk of these outcomes in an independent manner. These data support the concept that AF is a risk factor of future cardiovascular disease.
Catheter Ablation versus Standard Conventional Treatment in Patients with Left Ventricular Dysfunction and Atrial Fibrillation (CASTLE‐AF) ‐ Study Design
Authors: MARROUCHE NASSIR F. , BRACHMANN JOHANNES ,   on behalf of the CASTLE‐AF Steering Committee
Published: July 2009

Background: Electrical isolation of the pulmonary veins by catheter ablation is an emerging treatment modality for the treatment of atrial fibrillation (AF) and is increasingly used in patients with heart failure.
Methods: The catheter ablation versus standard conventional treatment in patients with left ventricular dysfunction and atrial fibrillation trial (CASTLE‐AF) is a randomized evaluation of ablative treatment of atrial fibrillation in patients with left ventricular dysfunction. The primary endpoint is the composite of all‐cause mortality or worsening of heart failure requiring unplanned hospitalization using a time to first event analysis. Secondary endpoints are all‐cause mortality, cardiovascular mortality, cerebrovascular accidents, worsening of heart failure requiring unplanned hospitalization, unplanned hospitalization due to cardiovascular reason, all‐cause hospitalization, quality of life, number of therapies (shock and antitachycardia pacing) delivered by the implantable cardioverter‐defibrillator (ICD), time to first ICD therapy, number of device‐detected ventricular tachycardia and ventricular fibrillation episodes, AF burden, AF free interval, left ventricular function, exercise tolerance, and percentage of right ventricular pacing. CASTLE‐AF will randomize 420 patients for a minimum of 3 years at 48 sites in the United States, Europe, Australia, and South America.
Atrial Fibrillation Ablation in Patients with Therapeutic International Normalized Ratios
Authors: SCHMIDT MARTIN , SEGERSON NATHAN M. , MARSCHANG HARALD , AKOUM NAZEM , RITTGER HARALD , CLIFFORD SARAH M. , BRACHMANN JOHANNES , DACCARETT MARCOS , MARROUCHE NASSIR F 
Published: July 2009

Aims: Pulmonary vein antrum isolation (PVAI) plays a pivotal role in the comprehensive treatment of atrial fibrillation (AF). The need for effective anticoagulation bridging following PVAI is associated with significant vascular complication rates and increased costs. We investigated the safety of PVAI in patients with therapeutic international normalized ratios (INR) the day of the procedure.
Methods: A case‐control analysis was performed on patients who underwent PVAI with therapeutic INR (>2). Patients with normal preprocedure INR served as controls. The incidence of major and minor hematomas, fistulas, vascular injury, and cardiac perforation or tamponade were catalogued. PVAI was performed under fluoroscopic, electro‐anatomical, and intracardiac echocardiographic guidance, with an open irrigation ablation technique.
Results: A total of 194 patients (mean age 64 ± 12) were included; 87 patients underwent PVAI with therapeutic INR (cases) and 107 with normal INR (controls). Persistent AF was more prevalent than paroxysmal AF in the therapeutic INR group. The mean INR for cases was 2.8 ± 0.7 compared to 1.4 ± 0.3 in the control group (P < 0.01). All procedures were completed without acute complications. Two major adverse events were observed, one in each arm. No significant difference in terms of minor (6.5% vs. 5.7%, P = 0.23) or major (0.93% vs. 1.15%, P = 0.49) vascular events or bleeding was detected between the therapeutic INR and the control group. The combined endpoint of major and minor complications did not differ among groups (9.35% vs. 8.05%, P = 0.19).
Conclusion: Atrial fibrillation ablation in patients with therapeutic INR on the day of a procedure appears to be safe and feasible. Expensive outpatient anti‐coagulation bridging may be safely avoided in this type of population.
Relevance of Echocardiographic Evaluation of Right Ventricular Function in Patients Undergoing Cardiac Resynchronization Therapy
Authors: SCUTERI LEA , RORDORF ROBERTO , MARSAN NINA AJMONE , LANDOLINA MAURIZIO , MAGRINI GIULIA , KLERSY CATHERINE , FRATTINI FOLCO , PETRACCI BARBARA , VICENTINI ALESSANDRO , CAMPANA CARLO , TAVAZZI LUIGI , GHIO STEFANO 
Published: July 2009

Aims: Right ventricular (RV) dysfunction is a marker of poor prognosis in heart failure (HF) patients. It is still unclear whether RV function might influence response to cardiac resynchronization therapy (CRT).
Methods: Forty‐four consecutive patients with HF, large QRS, and either intraventricular or interventricular dyssynchrony underwent echocardiographic evaluation before, 1 month after, and 6 months after CRT. Response to CRT was considered in case of significant LV reverse remodeling, defined as the occurrence of LV end‐systolic volume (LVESV) reduction ≥15% at 6 months.
Results: All echocardiographic indexes of baseline RV function and dimensions were significantly more impaired in nonresponders versus responders to CRT: tricuspid annular plane systolic excursion (TAPSE 15 ± 4 mm vs 20 ± 5 mm, P = 0.001), RV systolic pulmonary artery pressure (RVSP 39 ± 14 mmHg vs 27 ± 8 mmHg, P = 0.02), RV end‐diastolic area (RVEDA 23 ± 6 cm2 vs 16 ± 3 cm2 P < 0.001), RV end‐systolic area (RVESA 16 ± 6 cm2 vs 8 ± 2 cm2, P = 0.001), and RV fractional area change (30 ± 12% vs 48 ± 8%, P < 0.001). All the indexes of RV function significantly correlated with the percentage of LVESV reduction after CRT. Severe RV dysfunction was defined as TAPSE ≤14 mm and the population was stratified into two groups based on baseline TAPSE ≤ or > 14 mm. As compared to those with high TAPSE (n = 30), patients with low TAPSE (n = 14) were less likely to show LV reverse remodeling after CRT (76% vs 14%, P < 0.001).
Conclusions: Our study suggests that RV function significantly affects response to CRT. Poor LV reverse remodeling occurs after CRT in patients with HF having severe RV dysfunction at baseline.
Electrical Performance and Automatic Capture Characteristics of a 3.5‐mm2 Passive Fixation Lead during 1‐Year Follow‐Up
Authors: LOTZE ULRICH , FISCHER SVEN , HÖFS TILL , LIEBETRAU JOHANNES , FETTIN WOLFGANG , SCHEINER JÖRG , LANG ANDREAS ,   for the German IsoFlex Lead Registry Investigators
Published: July 2009

Background: Bipolar low polarization electrodes are recommended for a regular AutoCapture™ (St. Jude Medical, Inc., Sylmar, CA, USA) function in order to effectively detect the evoked response (ER) signal. The objective of this national multicenter registry was to evaluate the electrical performance and the AutoCapture™ characteristics of the bipolar ventricular pacing lead IsoFlex S, model 1636T or 1646T (St. Jude Medical), in combination with single‐ and dual‐chamber pacemakers.
Methods: Ventricular pacing and sensing thresholds, lead impedance, ER amplitude, and polarization signals were measured at discharge and routine follow‐up visits after 1, 3, 6, 9, and 12 months. AutoCapture™ activation was recommended based on the results of the ER sensitivity test.
Results: Of the 252 patients initially included, 109 (43%) have completed the follow‐up. The mean ventricular pacing threshold was 0.43 ± 0.19 V at discharge and 0.68 ± 0.32 V at 12 months postimplant. The values for the ventricular sensing threshold were between 9.51 ± 4.12 and 9.99 ± 4.09 mV at discharge and at the 12‐month follow‐up. The unipolar lead impedance decreased from 533 ± 94 to 476 ± 73 ohms during the follow‐up. The mean ER amplitude was 16.47 ± 6.70 mV at discharge and 17.42 ± 7.43 mV after 12 months, and the corresponding mean polarization signals were 0.59 ± 1.00 and 0.74 ± 1.24 mV, respectively. AutoCapture™ activation was recommended in at least 95% of the patients investigated over the 12‐month follow‐up.
Conclusion: The bipolar ventricular pacing lead IsoFlex S 1636/1646T shows a good electrical performance and is mostly compatible with the AutoCapture™ algorithm.
Impact of grazing regime on a Mongolian forest steppe
Authors: Van Staalduinen Marja A. , During Heinjo , Werger Marinus J.A. 
Published: July 2009

AbstractQuestion: What is the impact of grazing regime on plant species abundance, plant growth form, plant productivity and plant nutrient concentrations in a forest steppe?Location: Hustai National Park in the forest steppe region of Mongolia.Methods: On the Stipa steppe we applied three different grazing regimes by using; (1) one type of exclosure which excluded grazing by large mammalian herbivores, mainly takh (Przewalski horse), (2) another type of exclosure that excluded both large and small (Siberian marmots) mammalian herbivores, and (3) control plots which were freely grazed. We measured species frequencies, tiller densities, plant biomass and nitrogen concentrations of the vegetation.Results: Exclusion from grazing by takh and marmots significantly increased plant standing crop, but marmot grazing and full grazing did not show significant differences. Protection from grazing decreased forage quality, shown by a lower N‐concentration of the standing crop. However, this was solely the result of the lower live‐dead ratio of the vegetation. The frequency of the rhizomatous Leymus chinensis decreased under reduced grazing, as did the frequency of the total of rhizomatous species. The frequency of Stipa krylovii increased under reduced grazing, as did its basal areas, tiller density and tussock height.Conclusion: Reduced grazing leads to a lower abundance of rhizomatous species and an increase in tussock species.
Dynamics of species‐rich upland hay meadows over 15 years and their relation with agricultural management practices
Authors: Critchley C.N.R. , Fowbert J.A. , Wright B. 
Published: July 2009

AbstractQuestions: Has the species‐rich vegetation of upland hay meadows been maintained under low intensity management imposed by an agri‐environment scheme? Is the target plant community re‐establishing where it has been modified previously by intensive agricultural practices? What combinations of management practices and soil properties are associated with changes towards or away from the target community?Location: The Pennines, northern England, UK.Methods: A survey of 116 hay meadows in 1987 was repeated in 2002 by recording plant species in permanent quadrats. Changes in community variables (species richness, Ellenberg values, upland hay meadow community coefficients) were analysed in species‐rich, modified species‐rich and degraded grassland types. Redundancy Analysis and Generalised Linear Models were used to show the relationship between management practices and soil properties and change in species composition and community variables.Results: Few sites contained the species‐rich grassland type, and here forb richness declined. In the modified species‐rich type, total and grass species richness increased but Ellenberg N‐values also increased. Total and grass species richness increased in the degraded type and the community coefficient increased. Management was weakly related to change in species composition but showed clear relationships with the community variables. Re‐establishment of the target species‐rich community was more likely with late cutting, in the absence of cattle or prolonged spring grazing, and at lower soil nutrient status.Conclusion: The species‐rich community was not maintained but some reversion occurred in degraded grassland. Inorganic fertiliser application and intensive spring grazing should be avoided and cutting delayed until late July.
Using satellite imagery to assess plant species richness: The role of multispectral systems
Authors: Rocchini D. , Ricotta C. , Chiarucci A. 
Published: July 2009

AbstractQuestion: The use of variations in the spectral responses of remotely sensed images was recently proposed as an indicator of plant species richness (Spectral Variation Hypothesis, SVH). In this paper we addressed the issue of the potential use of multispectral sensors by testing the hypothesis that only some of the bands recorded in a remotely sensed image contain information related to the variation in species richness.Location: Montepulciano Lake, central Italy.Methods: We assessed how data compression techniques, such as Principal Component Analysis (PCA), influence the relationship between spectral heterogeneity and species richness and evaluated which spectral interval is the most adequate for predicting species richness by means of linear regression analysis.Results: The original multispectral data set and the first two non‐standardized principal components can both be used as predictors of plant species richness (R2∼ 0.48; p < 0.001), confirming that PCA is an effective tool for compressing multi‐spectral data without loss of information. Using single spectral bands, the near infrared band explained 41% of variance in species richness (p < 0.01), while the visible wavelengths had much lower prediction powers.Conclusions: The potential of satellite data for estimating species richness is likely to be due to the near infrared bands, rather than to the visible bands, which share highly redundant information. Since optimal band selection for image processing is a crucial task and it will assume increasing importance with the growing availability of hyperspectral data, in this paper we suggest a ‘near infrared way’for assessing species richness directly from remotely sensed data.
Long‐term effects of nitrogen deposition on vegetation in a deciduous forest near Munich, Germany
Authors: Bernhardt‐Römermann M. , Kudernatsch T. , Pfadenhauer J. , Kirchner M. , Jakobi G. , Fischer A. 
Published: July 2009

AbstractQuestion: What are the main reasons for changes in the spatial distribution of vegetation types during the last four decades?Location: Isolated small deciduous forest; surrounded by farmland in the northeast of Munich (Germany).Methods: Based on sequential vegetation mapping from the last four decades the spatial development of the vegetation was analysed. Additionally, environmental parameters (soil parameters, PAR, N‐deposition) have been analysed to describe the different vegetation types.Results: By linking the vegetation types to environmental parameters, it was possible to identify N‐deposition as the most important factor for the changes. In the 1960s to 1980s the replacement of vegetation types adapted to N‐poor conditions by N‐rich vegetation was very fast. A vegetation type containing species signifying soil impoverishment vanished totally, another vegetation type indicating nutrient poor conditions decreased dramatically. However, since 1985 up to now the decrease of N‐poor vegetation types has slowed, but is still ongoing. As a reason for the decreased rate of replacement, we stressed changes in the vertical structure: From 1961 to 1985 both N‐deposition as well as changes in vertical vegetation structure seem to be important. Since 1985 up to now only minor changes in vertical structure could be found; changes are mainly due to N‐availability.Conclusion: In this paper, the limitations of different methods to detect vegetation changes are discussed. We focus on the potentials of historical vegetation data and vegetation maps. It is shown that valuable information on N‐induced vegetation changes can be retrieved from historical vegetation data.
Using long‐term monitoring of fen hydrology and vegetation to underpin wetland restoration strategies
Authors: Large A.R.G. , Mayes W.M. , Newson M.D. , Parkin G. 
Published: July 2009

AbstractQuestion: How can long‐term monitoring of hydrological and ecological parameters support management strategies aimed towards wetland restoration and re‐creation in a complex hydrological system?Location: Newham Bog National Nature Reserve, Northumberland, UK, a site with a long history of active management, and recorded as drought‐sensitive over the last 100 years.Methods: Water level readings are correlated with longer‐term hydrological databases, and these data related to vegetation data collected intermittently over a 12 year period. Two analyses are undertaken: (1) a composite DCA analysis of 1993 and 2002 survey data to assess plant community transitions within the wetland and over time, and (2) analysis of recent vegetation data to explore wider vegetation gradients. This allows (3) communities to be classified using NVC classes and (4) integrated with revised Ellenberg F‐values.Results: Drought impact and subsequent hydrological recovery over a 22‐year period are quantified. Vegetation data display strong moisture and successional gradients. Analysis shows a shift from grassland communities toward mire communities across much of the site.Conclusion: The site is regionally unique in that it has a detailed long‐term monitoring record. Hydrological data and vegetation survey have allowed the impact of the most recent ‘groundwater’drought (1989–1997) to be quantified. This information on system resilience, combined with eco‐hydrological analyses of plant community‐water regime/quality relationships, provide a basis for recommendations concerning conservation and restoration.