A new species of Urocleidoides Mizelle & Price, 1964 from the gills of Schizodon nasutus Kner, 1858 (Characiformes, Anostomidae) in southeastern Brazil

Based on an integrative approach, this study describes a new species of Urocleidoides infesting Schizodon nasutus in the Paranapanema River basin, Brazil. The new species can be distinguished from its congeners by specific morphological features, including the shape of the male copulatory organ and accessory piece, the ventral bar shape, and the shape and size of the hooks. Molecular analyses, particularly of the 28S rDNA gene, suggest a close relationship between the new species and Urocleidoides paradoxus. The phylogenetic and taxonomic arrangement of Urocleidoides is discussed, as the analyses of the 28S rDNA and COI mtDNA resolved the genus as non-monophyletic, with Diaphorocleidus, Rhinoxenus, and Cacatuocotyle nested within it. Additional morphological and molecular data of other congeneric species are required to investigate the phylogenetic position and classification of Urocleidoides. This study underscores the significance of using integrative approaches in understanding host-parasite associations and phylogenetic relationships, contributing to the description of the freshwater fish parasite biodiversity in South America, particularly in the Paranapanema river basin.

Search for Evidence of Baryogenesis and Dark Matter in B^{+}→ψ_{D}+p Decays at BABAR

A new dark sector antibaryon, denoted ψ_{D}, could be produced in decays of B mesons. This Letter presents a search for B^{+}→ψ_{D}+p (and the charge conjugate) decays in e^{+}e^{-} annihilations at 10.58 GeV, using data collected in the BABAR experiment. Data corresponding to an integrated luminosity of 398  fb^{-1} are analyzed. No evidence for a signal is observed. Branching fraction upper limits in the range from 10^{-7}-10^{-5} are obtained at 90% confidence level for masses of 1.0 Collapse

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Major procedure-related complications in a real-world cohort of patients undergoing transvenous lead extraction

Funding Acknowledgements

Type of funding sources: None.

Background

Transvenous lead extraction (TLE) is the mainstay therapy for device-related infections. Though TLE procedures are associated with low complication and high success rates, risk factors for major procedure-related complications remain not well defined.

Purpose

To evaluate the safety and efficacy of TLE in a large single centre cohort and to identify risk factors for major complications.

Methods

All consecutive patients undergoing TLE in our department between May 2012 and December 2021 were included in a prospective registry. Our protocol for TLE followed a stepwise approach according to lead dwell time and estimated complexity of the procedure: use of simple traction ± locking stylet (LS) ± mechanical and/or powered sheaths ± snare technique via a femoral or jugular access. Patient characteristics, procedural data and complications were gathered and analysed. Logistic regression analysis was applied to identify risk factors for major procedure related complications.

Results

A total of 2218 leads (25.7% ICD leads) were targeted for TLE in 1060 patients (67.7 ± 14.8 years; 74% male). The mean lead dwell time was 82 ± 62 months. The leading indication for TLE was cardiac device related infection (CDRI) in 695 patients (65.6%), 373 (35.2%) had systemic and 322 (30.4%) localized infection. Leads were extracted by simple traction in 30%, traction with LS in 3.7%, dilator sheaths with LS in 47.7%, and additional use of powered mechanical sheaths in 14.6%. The snare technique was used in 3.9%, with additional venous entry from femoral in 3.5% and jugular in 1.0% of all targeted leads. TLE was completely successful in 92.6%, partially successful with lead fragments <4cm in 4.2%, and failed in 3.1% of all patients, which translated to a clinical success rate of 96.9%.

Twenty-nine patients (2.7%) experienced minor and 18 patients (1.7%) had major procedure-related complications (cardiac tamponade/perforation) including 2 intraprocedural deaths (0.2%). Presence of abandoned leads (HR 8.41, 95% CI 3.21–22.02; p<0.001), lead-years-per-patient (HR 1.063, 95% CI 1.037–1.090; p<0.001), dwelling time of the oldest lead (HR 1.011, 95% CI 1.006–1.016; p<0.001), and a right-sided implantation (HR 2.68, 95% CI 1.05–6.83; p=0.04) were significant predictors of major complications in logistic regression analysis.

Conclusion

TLE is feasible, effective and safe in our large single centre experience. Overall complication and failure rates are low. Following our TLE protocol, the presence of abandoned leads, a right-sided implantation and dwelling time of the extracted leads were associated with major procedure-related complications.

Prevalence and clinical impact of major incidental findings detected on routine cardiovascular resonance imaging prior to catheter ablation of atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Preprocedural contrast-enhanced cardiovascular magnetic resonance (CMR) or computed tomography (CT) imaging of the left atrium (LA) and pulmonary veins (PVs) is usually employed to facilitate catheter mapping and ablation of atrial fibrillation (AF). Incidental findings (IFs) are common on cardiac imaging prior to AF catheter ablation (AFCA). However, previous studies were of small size and have mainly focused on radiological extracardiac IFs detected on preprocedural CT scan.

Purpose

To assess the prevalence of major cardiac and extracardiac IFs on routine preprocedural CMR in a large cohort of consecutive patients scheduled for first-time AFCA, and to report its impact on clinical decision-making and management.

Methods

All consecutive patients who underwent routine preprocedural CMR prior to first-time AFCA between April 2015 and March 2019 were considered for analysis. Main exclusion criteria were referral for repeat AFCA; prior cardiac CT or CMR imaging; and general contraindication to CMR or AFCA. All CMR examinations consisted of survey images with full thoracic coverage, cardiac cine and late-gadolinium enhancement imaging, and three-dimensional contrast-enhanced CMR angiography of the LA/PVs. An IF was defined as major when any newly detected finding either resulted in cancellation of the AFCA procedure or intentional deviation from the standard AFCA protocol. In patients with accessory or anomalous PVs the ablation strategy was individually tailored aiming at isolation of all PVs.

Results

Two thousand consecutive patients (62±10 years; 59% male) with paroxysmal (48%) or persistent (52%) AF were included. Among the entire study cohort 172 patients (8.6%) had a total of 184 cardiac (75%) and extracardiac (25%) major IFs (Fig. A+B). Preprocedural detection of a major IF resulted in cancellation of the scheduled AFCA procedure in 88 patients (4.4%). Forty-two patients (2.1%) have thereupon never been ablated, 46 patients (2.3%) underwent postponed AFCA after a median time from CMR imaging of 83 (32-213) days. The remaining 84 patients with major IF (4.2%) underwent an individualized approach to AFCA (Fig. A). The most common major IFs were accessory or anomalous PVs in 76 (3.8%), extracardiac abnormalities suspicious of malignancy in 29 (1.5%), and positive stress perfusion imaging in 19 (1.0% overall; 7.2% of 261 tested) patients. In 19 patients (1.0%) preprocedural CMR detected a previously unknown intracardiac thrombus or structural cardiac disease.

Conclusion

Unexpected major IFs on routine preprocedural CMR affected clinical decision-making and therapeutic management in 8.6% of patients scheduled for first-time AFCA at our institution. Whether preprocedural CMR imaging may improve safety and outcome of AFCA needs to be addressed in future research.

The outcome spectrum for Dilated Cardiomyopathy and Ventricular Tachycardia: results from the prospective, multicenter, DCM-VT ablation study

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): The study was partially supported by an investigator initiated grant from Biosense Webster (a Johnson & Johnson company)

Background

Recurrent sustained ventricular tachycardia (VT) due to nonischemic dilated cardiomyopathy (DCM) is difficult to treat and long-term outcome data are limited.

Objective

We aimed to identify predictors for mortality or heart transplantation (MHT) and VT recurrence.

Methods

Consecutive DCM patients accepted for VT catheter ablation (RFCA) in 9 centers were prospectively enrolled and followed.

Results

Of 281 consecutive patients (age 60±13yrs, 85% men, LVEF 36±12%) 35% had VT storm, 20% incessant VT, and 68% failed amiodarone. During a median follow-up of 21 (IQR 6-30) months after RFCA (epicardial in 58%, no RFCA due to inaccessible target in 6.4%), 67(24%) patients died/underwent HT and 138(49%) had VT recurrence (45 within 30 days defined as early); the cumulative 4-year rate of VT or MHT was 70% and of MHT 38%.

In multivariable analysis predictors of MHT were early VT recurrence (HR 2.92 (CI1.37-6.21), p<0.01), amiodarone at discharge (HR 3.23 (CI1.43-7.33, p<0.01), renal dysfunction (HR 1.92 (CI1.01-3.64), p=0.046), and LVEF (HR 1.36 (CI 1.0-1.84), p=0.052). A LVEF ≤32% was the optimal threshold to identify patients at risk for MHT (AUC 0.75).

MHT per 100 person-years was 40.4 after early VT recurrence and significantly higher, compared to 14.2 after later VT recurrence and to 8.5 after RFCA with no VT recurrence (both p<0.01). Mortality rates for patients with VT recurrence after 30 days were not significantly higher than for patients with no VT recurrences

Patients with early recurrence and LVEF≤32% had a 1-year MHT rate of 55% (figure). VT recurrence was predicted by prior ICD shocks, basal antero-septal VT origin, and procedural failure but not LVEF.

Conclusion

DCM patients needing RFCA for VT are a high-risk group. Following RFCA half remain free of VT recurrences. Early VT recurrence with LVEF<0.32 identifies those with a very high risk and screening for mechanical support/ HT should be considered. Late VT recurrence after RFCA does not predict worse outcome.

Search for an Axionlike Particle in B Meson Decays

Axionlike particles (ALPs) are predicted in many extensions of the standard model, and their masses can naturally be well below the electroweak scale. In the presence of couplings to electroweak bosons, these particles could be emitted in flavor-changing B meson decays. We report herein a search for an ALP, a, in the reaction B^{±}→K^{±}a, a→γγ using data collected by the BABAR experiment at SLAC. No significant signal is observed, and 90% confidence level upper limits on the ALP coupling to electroweak bosons are derived as a function of ALP mass, improving current constraints by several orders of magnitude in the range 0.175  GeV<m_{a}<4.78  GeV.

Search for Lepton Flavor Violation in ϒ(3S)→e^{±}μ^{∓}

We report on the first search for electron-muon lepton flavor violation (LFV) in the decay of a b quark and b antiquark bound state. We look for the LFV decay ϒ(3S)→e^{±}μ^{∓} in a sample of 118 million ϒ(3S) mesons from 27  fb^{-1} of data collected with the BABAR detector at the SLAC PEP-II e^{+}e^{-} collider operating with a 10.36 GeV center-of-mass energy. No evidence for a signal is found, and we set a limit on the branching fraction B[ϒ(3S)→e^{±}μ^{∓}]<3.6×10^{-7} at 90% C. L. This result can be interpreted as a limit Λ_{NP}/g_{NP}^{2}>80  TeV on the energy scale Λ_{NP} divided by the coupling-squared g_{NP}^{2} of relevant new physics (NP).

Search for Darkonium in e^{+}e^{-} Collisions

Collider searches for dark sectors, new particles interacting only feebly with ordinary matter, have largely focused on identifying signatures of new mediators, leaving much of dark sector structures unexplored. In particular, the existence of dark matter bound states (darkonia) remains to be investigated. This possibility could arise in a simple model in which a dark photon (A^{'}) is light enough to generate an attractive force between dark fermions. We report herein a search for a J^{PC}=1^{--} darkonium state, the ϒ_{D}, produced in the reaction e^{+}e^{-}→γϒ_{D}, ϒ_{D}→A^{'}A^{'}A^{'}, where the dark photons subsequently decay into pairs of leptons or pions, using 514  fb^{-1} of data collected with the BABAR detector. No significant signal is observed, and we set bounds on the γ-A^{'} kinetic mixing as a function of the dark sector coupling constant for 0.001<m_{A^{'}}<3.16  GeV and 0.05<m_{ϒ_{D}}<9.5  GeV.

Study into the spread of heat from thermo-optic silicon photonic elements

Phase modulators based upon the thermo-optic effect are used widely in silicon photonics for low speed applications such as switching and tuning. The dissipation of the heat produced to drive the device to the surrounding silicon is a concern as it can dictate how compact and tightly packed components can be without concerns over thermal crosstalk. In this paper we study through modelling and experiment, on various silicon on insulator photonic platforms, how close waveguides can be placed together without significant thermal crosstalk from adjacent devices.

Pleomorphic ventricular tachycardia in dilated cardiomyopathy is a strong predictor of VT recurrence after ablation independent of cardiac function: Comparison with ischemic cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Background

 

Compared to ICM patients, subgroups of DCM patients show higher VT recurrence rates after catheter ablation (CA), despite similar percentages of acute non-inducibility. Pleomorphic VTs (PL-VT) have been reported in ICM patients with fibrotic remodeling and progressive heart failure.  Diffuse fibrosis is the dominant scar pattern in DCM. In these patients PL-VT may occur independent of cardiac function. 

Aim

 

To investigate the prevalence, relation with cardiac function, and impact of PL-VT on long-term ablation outcome in patients with ICM and DCM. 

Methods

 

Consecutive patients with ICM or DCM undergoing VT ablation (ICM 2009-2016; DCM 2008-2018) were included. PL-VT was defined as ≥1 spontaneous change of the 12-lead VT morphology lasting for ≥6 consecutive beats during the same induced VT episode. Complete procedural success was defined as non-inducibility of any VT at the end of the procedure. Patients were followed for VT recurrence and mortality. 

Results

 

A total of 247 patients (86% men, age 63 ± 13 years) underwent CA for monomorphic VT, 152 with ICM (62%), and 95 with DCM (38%). Complete procedural success was achieved in 39% in ICM vs. 37% in DCM, respectively. PL-VT was observed in 22 and 29 patients with ICM and DCM, respectively (14% vs. 31%, P = 0.003). Among ICM patients, PL-VT was associated with a lower LVEF (PL-VT+ 28 ± 9% vs. PL-VT- 34 ± 12%, P = 0.02) and only occurred if LVEF was &lt;40%. In contrast, in DCM patients, PL-VT was not related to cardiac function and occurred in 27% of patients with an EF &gt;40%. After propensity score matching to account for baseline differences (age, gender, LVEF, prior VT ablation, VT storm, and amiodarone use), between ICM vs. DCM patients, the PLVT incidence was 4 times higher in DCM patients (7% [4/60] vs. 28% [17/60], P = 0.003).  

During a median follow-up of 30 months, 79 (32%) patients died (ICM 48 [32%), DCM 31 [33%], P = 0.88) and 120 (49%) patients had VT recurrence (ICM 59 [39%], DCM 61 [64%], P &lt; 0.001). In Kaplan-Meier analyses, inducibility of PL-VT was associated with mortality only in ICM but not in DCM patients. In contrast, PL-VT was associated with poorer VT-free survival in both ICM and DCM patients (figure). In multivariate analyses, PL-VT remained a significant predictor of VT recurrence in DCM (HR 3.00, 95% CI 1.75-5.11, P &lt; 0.001), independent of LVEF, (likely) pathogenic genetic mutation, amiodarone, endocardial low bipolar/unipolar voltage areas, dominant anteroseptal substrate, and non-complete acute procedural success, but not in ICM.

Conclusions

 

PL-VT was associated with poor systolic function and mortality in ICM, whereas it was independent of LVEF and the most decisive parameter for VT recurrence in DCM. This data suggests that PL-VT in DCM is a marker of a complex arrhythmic substrate challenging to control by CA. Abstract Figure. Kaplan-Meier analyses

Volume-weighted unipolar endocardial voltage: An excellent, novel parameter for predicting cardiac mortality in patients with dilated cardiomyopathy and ventricular arrhythmias

Funding Acknowledgements

Type of funding sources: None.

Background

Patients with dilated cardiomyopathy (DCM) and ventricular tachyarrhythmias (VT) are at risk for heart failure (HF) death. Global left ventricular endocardial voltage may reflect the amount of excitable viable myocardium and identify patients at risk for rapid progression to end-stage HF. 

Aim

To determine if volume-weighted endocardial voltage, as a surrogate for the total excitable viable myocardium, predicts mortality in patients with DCM and VT. 

Methods

Consecutive patients with DCM, who underwent high-density endocardial voltage mapping for VT or PVC ablation (2012-2018), were included. Mapping data were transferred from CARTO to ParaView after excluding valve areas. The volume-weighted UV and BV (vwUV, vwBW) were calculated by mathematically integrating the UV and BV over the whole LV (thereby correcting for mapping density heterogeneity) divided by the endocardial LV surface area and corrected for LV wall thickness determined by echocardiography. The prognostic values of vwUV and vwBV for cardiac function and cardiac death were evaluated.

Results

One hundred three patients (VT, n = 83 and PVC, n = 20; age, 57 ± 14yrs; LVEF, 39 ± 13%; [likely] pathogenic genetic variants 33 [32%]; amiodarone use 36 [35%]) were included. VwUV and vwBV were 9.94 ± 3.42 and 4.70 ± 1.46. During a median follow-up of 24 months, cardiac mortality was 18% (end-stage HF 16/19, the median time to death 5.7 months). Patients who died had a significantly lower vwUV and vwBV (vwUV 5.62 ± 0.93 vs. 10.91 ± 3.10, P &lt; 0.001; vwBV 2.99 ± 0.70 vs. 5.04 ± 1.28, P &lt; 0.001). The optimal cutoff of vwUV for predicting HF-related death was 6.64 (AUC, 0.98; Sensitivity, 94%; Specificity, 95%), superior to LVEF or vwBV (AUC, 0.77, 0.92, respectively, Figure A). In multivariable analysis, vwUV remained the only significant predictor for cardiac death (for one decrease, HR 2.66, CI 1.41-5.00, P = 0.002), independently of LVEF, NT-proBNP, vwBV, genetic variants, and amiodarone use. In a subanalysis, the correlations between vwUV and changes of LVEF over time after voltage mapping were analyzed in patients with mid-range (HFmrEF, EF40-49%, n = 27) and reduced (HFrEF, EF &lt; 40%, n = 53) LVEF, respectively. In patients with HFmrEF, a significant LVEF deterioration (defined as an EF decrease &gt;5% and transition to HFrEF) occurred in 22% and was strongly related with a low vwUV (6.65 ± 1.15 vs. 10.08 ± 2.92, P = 0.02, Figure B left). Furthermore, in patients with HFrEF, a significant LVEF improvement (defined as an EF increase &gt;5% and transition to HFmrEF) was noted in 32% and was correlated with a high vwUV (11.68 ± 2.70 vs. 8.62 ± 2.69, P = 0.002, Figure B right).

Conclusion

VwUV is a newly proposed surrogate for the amount of LV viable myocardium, available from routine endocardial mapping and an excellent parameter to identify patients with DCM at high risk for rapid progression to HF-related death. Abstract Figure. vwUV and outcomes

Efficacy of Retreatment After Failed Direct-acting Antiviral Therapy in Patients With HCV Genotype 1-3 Infections

Hepatitis C virus infection is causing chronic liver disease, cirrhosis, and hepatocellular carcinoma. By combining direct-acting antivirals (DAAs), high sustained virologic response rates (SVRs) can be achieved. Resistance-associated substitutions (RASs) are commonly observed after DAA failure, and especially nonstructural protein 5A (NS5A) RASs may impact retreatment options.^1-3 Data on retreatment of DAA failure patients using first-generation DAAs are limited.^4-7 Recently, a second-generation protease- and NS5A-inhibitor plus sofosbuvir (voxilaprevir/velpatasvir/sofosbuvir [VOX/VEL/SOF]) was approved for retreatment after DAA failure.⁸ However, this and other second-generation regimens are not available in many resource-limited countries or are not reimbursed by regular insurance, and recommendations regarding the selection of retreatment regimens using first-generation DAAs are very important. This study aimed to analyze patients who were re-treated with first-generation DAAs after failure of a DAA combination therapy.

Precision Measurement of the Ratio B(ϒ(3S)→τ^{+}τ^{-})/B(ϒ(3S)→μ^{+}μ^{-})

We report on a precision measurement of the ratio R_{τμ}^{ϒ(3S)}=B(ϒ(3S)→τ^{+}τ^{-})/B(ϒ(3S)→μ^{+}μ^{-}) using data collected with the BABAR detector at the SLAC PEP-II e^{+}e^{-} collider. The measurement is based on a 28  fb^{-1} data sample collected at a center-of-mass energy of 10.355 GeV corresponding to a sample of 122 million ϒ(3S) mesons. The ratio is measured to be R_{τμ}^{ϒ(3S)}=0.966±0.008_{stat}±0.014_{syst} and is in agreement with the standard model prediction of 0.9948 within 2 standard deviations. The uncertainty in R_{τμ}^{ϒ(3S)} is almost an order of magnitude smaller than the only previous measurement.

Incidence and causes of in-hospital mortality in cardiac device-related infections

Introduction

Cardiac device-related infections (CDRI) are associated with increased in-hospital mortality despite effective treatment by transvenous lead extraction (TLE) and antibiotic therapy. Data on mortality and causes of death are scarce and predictors of mortality are not well defined.

Purpose

To analyse the incidence and causes of mortality in CDRI and identify predictors of mortality in a large single centre experience.

Methods

All patients undergoing TLE for CDRI in our department between May 2012 and January 2020 were included in a prospective registry. Patient characteristics, procedural and follow-up data were collected and analysed. A Kaplan-Meier analysis was used to analyse the influence of different infection types on mortality. Univariate and multivariate cox regression analysis was applied to identify risk factors for mortality.

Results

Among 561 consecutive patients (72±12 years; 77% male) treated for CDRI (51.2% systemic and 48.8% localized infection), 61 patients (10.9%) died during the index hospitalization. The most frequent cause of death was severe systemic infection or sepsis in 38 patients (6.8%), followed by end-stage heart failure (9; 1.6%), respiratory insufficiency (3; 0.5%), ventricular arrhythmias (3; 0.5%), asystole (2; 0.4%), pulmonary embolism (2; 0.4%), acute enteric ischemia (2; 0.4%), mechanical ileus (1; 0.2%), and unwitnessed sudden death (1; 0.2%). Patients who died had significantly more often systemic infections (p&lt;0.001), positive blood cultures (p&lt;0.001), severe renal dysfunction (GFR &lt;30ml/min; p&lt;0.001), heart failure with reduced ejection fraction (HFrEF; p=0.001), and diabetes (p=0.004). Kaplan-Meier survival analysis showed a significantly higher mortality in patients with systemic CDRI as compared to localized infection (log-rank p&lt;0.001). Several factors were predictors of mortality in univariate analysis: systemic infection (HR 4.64, 95% CI 2.18–9.84; p&lt;0.001), GFR &lt;30 ml/min (HR 4.27, 95% CI 2.57–7.09; p&lt;0.001), vegetation in TOE (HR 3.68, 95% CI 1.78–7.43; p&lt;0.001), positive blood cultures (HR 2.52, 95% CI 1.46–4.37; p=0.001), diabetes (HR 1.89, 95% CI 1.12–3.18; p=0.018), HFrEF (HR 1.83, 95% CI 1.09–3.05; p=0.021), tricuspid regurgitation (HR 1.79, 95% CI 1.21–2.65, p=0.004), and days from hospital admission to explant (HR 1.04, 95% CI 1.02–1.06; p&lt;0.001). Multivariate analysis revealed severe renal dysfunction (HR 2.71, 95% CI 1.47–5.00; p=0.001) and days from hospital admission to TLE (HR 1.029, 95% CI 1.004–1.055, p=0.021) as independent predictors of in-hospital mortality.

Conclusion

In-hospital mortality in CDRI is particularly high in patients with severe systemic infection and sepsis despite state-of the-art treatment. Delayed TLE is associated with an increased in-hospital mortality. Therefore, TLE should be performed early in the course of CDRI, particularly in patients with severe systemic infection.

Funding Acknowledgement

Type of funding source: None

Predictors of major procedure-related complications in transvenous lead extraction

Background

Transvenous lead extraction (TLE) has become the mainstay therapy for device-related infections. Though TLE procedures are associated with low complication and high success rates, risk factors for major procedure-related complications remain not well defined.

Purpose

To evaluate the safety and efficacy of TLE in a large single centre cohort and to identify risk factors for major complications.

Methods

All consecutive patients who had undergone TLE in our department between May 2012 and January 2020 were included in a prospective registry. Our protocol for TLE followed a stepwise approach according to lead dwell time and estimated complexity of the procedure: use of simple traction ± locking stylet (LS) ± mechanical and/or powered sheaths ± snare technique. In case of unsuccessful extraction from the venous entry site, femoral or jugular access was approached. Patient characteristics, procedural data and complications were gathered and analysed. Logistic regression analysis was applied to identify risk factors for major procedure-related complications.

Results

A total of 1717 leads (443 [25.9%] ICD leads) were targeted for TLE in 810 patients (67±15 years; 76% male). The mean lead dwell time was 83±60 months. The leading indication for TLE was cardiac device related infection (CDRI) in 527 patients (65.1%), of whom 273 (51.8%) had systemic and 254 (48.2%) localized infection. Two hundred eighty-three patients (34.9%) underwent TLE for non-CDRI causes. Leads were extracted by simple traction in 28.2%, traction with LS in 4.1%, dilator sheaths with LS in 50.1%, and additional use of powered mechanical sheaths in 13.0%. The snare technique was used in 4.6%. Venous access for TLE was exclusively from the entry site in 94.8%, combined from femoral in 4.0% and jugular in 1.2%. TLE was completely successful in 96.2%, partially successful in 2.1%, and failed in 1.7% of all attempted leads, which translated to a clinical success rate of 96.8%.

Eighteen patients (2.2%) experienced minor and 12 patients (1.5%) had major procedure-related complications (cardiac tamponade/perforation) including one intraprocedural death (0.1%) from fulminant pulmonary embolism. Lead-years-per-patient (HR 1.064, 95% CI 1.032–1.096; p&lt;0.001), dwelling time of the oldest lead (HR 1.013, 95% CI 1.007–1.019; p&lt;0.001), and BMI (HR 0.877, 95% CI 0.772–0.997; p=0.020) were significant predictors for major complications in logistic regression analysis.

Conclusion

TLE is feasible, effective and safe in our large single centre experience. Overall complication and failure rates are low. Following our TLE protocol, dwelling time of the extracted leads and low BMI were associated with major procedure-related complications.

Funding Acknowledgement

Type of funding source: None

Search for a Dark Leptophilic Scalar in e^{+}e^{-} Collisions

Many scenarios of physics beyond the standard model predict the existence of new gauge singlets, which might be substantially lighter than the weak scale. The experimental constraints on additional scalars with masses in the MeV to GeV range could be significantly weakened if they interact predominantly with leptons rather than quarks. At an e^{+}e^{-} collider, such a leptophilic scalar (ϕ_{L}) would be produced predominantly through radiation from a τ lepton. We report herein a search for e^{+}e^{-}→τ^{+}τ^{-}ϕ_{L}, ϕ_{L}→ℓ^{+}ℓ^{-} (ℓ=e, μ) using data collected by the BABAR experiment at SLAC. No significant signal is observed, and we set limits on the ϕ_{L} coupling to leptons in the range 0.04<m_{ϕ_{L}}<7.0  GeV. These bounds significantly improve upon the current constraints, excluding almost entirely the parameter space favored by the observed discrepancy in the muon anomalous magnetic moment below 4 GeV at 90% confidence level.

Integration of low loss vertical slot waveguides on SOI photonic platforms for high efficiency carrier accumulation modulators

Silicon accumulation type modulators offer prospects of high power efficiency, large bandwidth and high voltage phase linearity making them promising candidates for a number of advanced electro-optic applications. A significant challenge in the realisation of such a modulator is the fabrication of the passive waveguide structure which requires a thin dielectric layer to be positioned within the waveguide, i.e. slotted waveguides. Simultaneously, the fabricated slotted waveguide should be integrated with conventional rib waveguides with negligible optical transition losses. Here, successful integration of polysilicon and silicon slot waveguides enabling a low propagation loss 0.4-1.2 dB/mm together with an ultra-small optical mode conversion loss 0.04 dB between rib and slot waveguides is demonstrated. These fabricated slot waveguide with dielectric thermal SiO₂ layer thicknesses around 6 nm, 8 nm and 10 nm have been characterized under transmission electron microscopy allowing for strong carrier accumulation effects for MOS-capacitor electro-optic modulators.

Measurements of the Absolute Branching Fractions of B^{±}→K^{±}X_{cc[over ¯]}

A study of the two-body decays B^{±}→X_{cc[over ¯]}K^{±}, where X_{cc[over ¯]} refers to one charmonium state, is reported by the BABAR Collaboration using a data sample of 424  fb^{-1}. The absolute determination of branching fractions for these decays are significantly improved compared to previous BABAR measurements. Evidence is found for the decay B^{+}→X(3872)K^{+} at the 3σ level. The absolute branching fraction B[B^{+}→X(3872)K^{+}]=[2.1±0.6(stat)±0.3(syst)]×10^{-4} is measured for the first time. It follows that B[X(3872)→J/ψπ^{+}π^{-}]=(4.1±1.3)%, supporting the hypothesis of a molecular component for this resonance.

A clinical decision support system improves antibiotic therapy for upper urinary tract infection in a randomized single-blinded study

BACKGROUND

Due to increasing bacterial resistance rates choosing a correct empiric antibiotic therapy is getting more and more complex. Often medical doctors use information tools to make the right treatment choice.

METHODS

One hundred sixty six participants (77 medical doctors and 89 medical students) were asked to provide a diagnosis and antibiotic therapy in a simple fictive paper case of upper urinary tract infection (UTI) in a randomized single-blinded study. Participants were randomized to one of four information tools they were allowed to use in the study or control: 1. free internet access, 2. pharmaceutical pocket guide, 3. pocket guide antibiotic therapy, 4. clinical decision support system (CDSS), and control (no information tool). The CDSS was designed for the study. The adherence to the national German UTI guideline was evaluated.

RESULTS

Only 27.1% (n = 45/166) provided a correct diagnosis of upper UTI and 19.4% (n = 32/166) an antibiotic treatment recommended by national German treatment guidelines indicating their need for information tools. This result was not significantly different between medical doctors and medical students, residents and medical specialists or level of working experience. Using CDSS improved results significantly compared to conventional tools (diagnosis 57.1%; treatment recommendation 40.5%; p < 0,01). Processing time was not different between the use of CDSS and conventional information tools. CDSS users based their decision making on their assigned information tool more than users of conventional tools (73.8% vs. 48.0%; p < 0.01). Using CDSS improved the confidence of participants in their recommendation significantly compared to conventional tools (p < 0.01).

CONCLUSIONS

Our study suggests that medical professionals require information tools in diagnosing and treating a simple case of upper UTI correctly. CDSS appears to be superior to conventional tools as an information source.

Search for Rare or Forbidden Decays of the D^{0} Meson

We present a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type D^{0}→h^{'-}h^{-}ℓ^{'+}ℓ^{+} and D^{0}→h^{'-}h^{+}ℓ^{'±}ℓ^{∓}, where h and h^{'} represent a K or π meson and ℓ and ℓ^{'} an electron or muon. The analysis is based on 468  fb^{-1} of e^{+}e^{-} annihilation data collected at or close to the ϒ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the twelve modes, and we establish 90% confidence level upper limits on the branching fractions in the range (1.0-30.6)×10^{-7}. The limits are between 1 and 3 orders of magnitude more stringent than previous measurements.

Rydberg-Mediated Entanglement in a Two-Dimensional Neutral Atom Qubit Array

We demonstrate high fidelity two-qubit Rydberg blockade and entanglement on a pair of sites in a large two-dimensional qubit array. The qubit array is defined by a grid of blue detuned lines of light with 121 sites for trapping atomic qubits. Improved experimental methods have increased the observed Bell state fidelity to F_{Bell}=0.86(2). Accounting for errors in state preparation and measurement we infer a fidelity of F_{Bell}^{-SPAM}=0.88. Accounting for errors in single qubit operations we infer that a Bell state created with the Rydberg mediated C_{Z} gate has a fidelity of F_{Bell}^{C_{Z}}=0.89. Comparison with a detailed error model based on quantum process matrices indicates that finite atom temperature and laser noise are the dominant error sources contributing to the observed gate infidelity.

P5701Impact of VT pleomorphism on the prognostic value of non-inducibility after catheter ablation in patients with non-ischemic cardiomyopathy

Background

In patients with non-ischemic cardiomyopathy (NICM), non-inducibility after catheter ablation has been associated with lower VT recurrence rates. We hypothesized that induced VT pleomorphism (PL-VT) may be indicative for a complex VT substrate that might be associated with poor ablation outcome independently of non-inducibility at the end of the procedure.

Methods

Consecutive patients with left-dominant NICM undergoing VT ablation (2008–2018) were included. All patients underwent genetic screening. PL-VT was defined as occurrence of ≥1 morphologically distinct QRS lasting for ≥6 consecutive beats during the same induced VT episode. Complete acute success was defined as non-inducibility of any VT at the end of procedure.

Results

Eighty-five patients (56±15 yrs, LVEF 38±12%), inducible for 365 VTs (median 3/patient, IQR 1–6) were included. PL-VT was observed in 29 patients (34%). Patients with PL-VT had more often anteroseptal substrates, a higher number of induced VTs, and larger endocardial bipolar (<1.5 mV) and unipolar low voltage (<8.01 mV) areas. Pathogenic genetic mutations were more frequently recognized in patients with PL-VT than in those without (59 vs. 34%, P=0.03), but there was no significant correlation in each representative mutation (Lamin A/C, Phospholamban, or Titin). Complete acute success was achieved in 34 patients (40%) and comparable between patients with PL-VT and those without (41 vs. 39%, P=0.85). After a median of 24 months, 53 patients (62%) had VT recurrence and 23 (27%) died. In multivariate Cox regression analysis, PL-VT and inducibility of any VT were significantly associated with VT recurrence (HR 4.07, CI 1.82–8.92; P=0.001, HR 2.22, CI 1.10–4.78; P=0.026, respectively) independent of NYHA, LVEF, electrical storm, genetic mutations, low voltage area, substrate location, and number of induced VTs. Of importance, the co-existence of PL-VT and persistent VT inducibility identified those at highest risk for VT recurrence after 2-years. (PL-VT (−)/complete success, 27%, PL-VT (−)/non-complete success, 50%, PL-VT (+)/complete success, 58%, PL-VT (+)/non-complete success 94%, Log-rank P<0.001, see figure).

Figure 1

Conclusions

Induced PL-VT was not associated with acute outcome but higher VT recurrence rate after catheter ablation in patients with NICM. Moreover, co-existence of PL-VT and persistent VT inducibility identifies patients at highest risk for VT recurrence whereas non-inducible patients without PL-VT have a favorable prognosis.

Extraction of form Factors from a Four-Dimensional Angular Analysis of B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ}

An angular analysis of the decay B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ}, ℓ∈{e,μ}, is reported using the full e^{+}e^{-} collision data set collected by the BABAR experiment at the ϒ(4S) resonance. One B meson from the ϒ(4S)→BB[over ¯] decay is fully reconstructed in a hadronic decay mode, which constrains the kinematics and provides a determination of the neutrino momentum vector. The kinematics of the semileptonic decay is described by the dilepton mass squared, q^{2}, and three angles. The first unbinned fit to the full four-dimensional decay rate in the standard model is performed in the so-called Boyd-Grinstein-Lebed approach, which employs a generic q^{2} parametrization of the underlying form factors based on crossing symmetry, analyticity, and QCD dispersion relations for the amplitudes. A fit using the more model-dependent Caprini-Lellouch-Neubert (CLN) approach is performed as well. Our form factor shapes show deviations from previous fits based on the CLN parametrization. The latest form factors also provide an updated prediction for the branching fraction ratio R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ})=0.253±0.005. Finally, using the well-measured branching fraction for the B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ} decay, a value of |V_{cb}|=(38.36±0.90)×10^{-3} is obtained that is consistent with the current world average for exclusive B[over ¯]→D^{(*)}ℓ^{-}ν[over ¯]_{ℓ} decays and remains in tension with the determination from inclusive semileptonic B decays to final states with charm.

Test of the Einstein Equivalence Principle near the Galactic Center Supermassive Black Hole

During its orbit around the four million solar mass black hole Sagittarius A* the star S2 experiences significant changes in gravitational potential. We use this change of potential to test one part of the Einstein equivalence principle: the local position invariance (LPI). We study the dependency of different atomic transitions on the gravitational potential to give an upper limit on violations of the LPI. This is done by separately measuring the redshift from hydrogen and helium absorption lines in the stellar spectrum during its closest approach to the black hole. For this measurement we use radial velocity data from 2015 to 2018 and combine it with the gravitational potential at the position of S2, which is calculated from the precisely known orbit of S2 around the black hole. This results in a limit on a violation of the LPI of |β_{He}-β_{H}|=(2.4±5.1)×10^{-2}. The variation in potential that we probe with this measurement is six magnitudes larger than possible for measurements on Earth, and a factor of 10 larger than in experiments using white dwarfs. We are therefore testing the LPI in a regime where it has not been tested before.

Observation of the Decay D^{0}→K^{-}π^{+}e^{+}e^{-}

We report the observation of the rare charm decay D^{0}→K^{-}π^{+}e^{+}e^{-}, based on 468  fb^{-1} of e^{+}e^{-} annihilation data collected at or close to the center-of-mass energy of the ϒ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. We find the branching fraction in the invariant mass range 0.675<m(e^{+}e^{-})<0.875  GeV/c^{2} of the electron-positron pair to be B(D^{0}→K^{-}π^{+}e^{+}e^{-})=(4.0±0.5±0.2±0.1)×10^{-6}, where the first uncertainty is statistical, the second systematic, and the third due to the uncertainty in the branching fraction of the decay D^{0}→K^{-}π^{+}π^{+}π^{-} used as a normalization mode. The significance of the observation corresponds to 9.7 standard deviations including systematic uncertainties. This result is consistent with the recently reported D^{0}→K^{-}π^{+}μ^{+}μ^{-} branching fraction, measured in the same invariant mass range, and with the value expected in the standard model. In a set of regions of m(e^{+}e^{-}), where long-distance effects are potentially small, we determine a 90% confidence level upper limit on the branching fraction B(D^{0}→K^{-}π^{+}e^{+}e^{-})<3.1×10^{-6}.

Search for a Stable Six-Quark State at BABAR

Recent investigations have suggested that the six-quark combination uuddss could be a deeply bound state (S) that has eluded detection so far, and a potential dark matter candidate. We report the first search for a stable, doubly strange six-quark state in ϒ→SΛ[over ¯]Λ[over ¯] decays based on a sample of 90×10^{6}ϒ(2S) and 110×10^{6}ϒ(3S) decays collected by the BABAR experiment. No signal is observed, and 90% confidence level limits on the combined ϒ(2S,3S)→SΛ[over ¯]Λ[over ¯] branching fraction in the range (1.2-1.4)×10^{-7} are derived for m_{S}<2.05  GeV. These bounds set stringent limits on the existence of such exotic particles.

First Evidence for cos2β>0 and Resolution of the Cabibbo-Kobayashi-Maskawa Quark-Mixing Unitarity Triangle Ambiguity

We present first evidence that the cosine of the CP-violating weak phase 2β is positive, and hence exclude trigonometric multifold solutions of the Cabibbo-Kobayashi-Maskawa (CKM) Unitarity Triangle using a time-dependent Dalitz plot analysis of B^{0}→D^{(*)}h^{0} with D→K_{S}^{0}π^{+}π^{-} decays, where h^{0}∈{π^{0},η,ω} denotes a light unflavored and neutral hadron. The measurement is performed combining the final data sets of the BABAR and Belle experiments collected at the ϒ(4S) resonance at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The data samples contain (471±3)×10^{6}BB[over ¯] pairs recorded by the BABAR detector and (772±11)×10^{6}BB[over ¯] pairs recorded by the Belle detector. The results of the measurement are sin2β=0.80±0.14(stat)±0.06(syst)±0.03(model) and cos2β=0.91±0.22(stat)±0.09(syst)±0.07(model). The result for the direct measurement of the angle β of the CKM Unitarity Triangle is β=[22.5±4.4(stat)±1.2(syst)±0.6(model)]°. The measurement assumes no direct CP violation in B^{0}→D^{(*)}h^{0} decays. The quoted model uncertainties are due to the composition of the D^{0}→K_{S}^{0}π^{+}π^{-} decay amplitude model, which is newly established by performing a Dalitz plot amplitude analysis using a high-statistics e^{+}e^{-}→cc[over ¯] data sample. CP violation is observed in B^{0}→D^{(*)}h^{0} decays at the level of 5.1 standard deviations. The significance for cos2β>0 is 3.7 standard deviations. The trigonometric multifold solution π/2-β=(68.1±0.7)° is excluded at the level of 7.3 standard deviations. The measurement resolves an ambiguity in the determination of the apex of the CKM Unitarity Triangle.

Multichannel ZnO nanowire field effect transistors by lift-off process

This paper describes a new, low-cost, top-down fabrication process, which makes it possible to define nanowire field effect transistor arrays with different numbers of nanowires simultaneously and systematically comparing their electrical performance. The main feature of this process is a developed bilayer photoresist pattern with a retrograde profile, which enables the modification of the nanowire in width, length, height and the number of transistor channels. The approach is compatible with low-cost manufacture without electron beam lithography, and benefits from process temperatures below 190 °C. Process reliability has been investigated by scanning electron microscopy, transmission electron microscopy and atomic force microscopy. Electrical measurements demonstrate enhancement mode transistors, which show a scalable correlation between the number of nanowires and the electrical characteristics. Devices with 100 nanowires exhibit the best performance with a high field effect mobility of 11.0 cm² Vs^-1, on/off current ratio of 3.97 × 10⁷ and subthreshold swing of 0.66 V dec^-1.

Amplitude Analysis of the Decay B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} and First Observation of the CP Asymmetry in B[over ¯]^{0}→K^{*}(892)^{-}π^{+}

The time-integrated untagged Dalitz plot of the three-body hadronic charmless decay B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} is studied using a pp collision data sample recorded with the LHCb detector, corresponding to an integrated luminosity of 3.0  fb^{-1}. The decay amplitude is described with an isobar model. Relative contributions of the isobar amplitudes to the B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} decay branching fraction and CP asymmetries of the flavor-specific amplitudes are measured. The CP asymmetry between the conjugate B[over ¯]^{0}→K^{*}(892)^{-}π^{+} and B^{0}→K^{*}(892)^{+}π^{-} decay rates is determined to be -0.308±0.062.

Studies of the resonance structure in D 0 → K ∓ π ± π ± π ∓ decays

Amplitude models are constructed to describe the resonance structure of D 0 → K - π + π + π - and D 0 → K + π - π - π + decays using pp collision data collected at centre-of-mass energies of 7 and 8 TeV with the LHCb experiment, corresponding to an integrated luminosity of 3.0  f b - 1 . The largest contributions to both decay amplitudes are found to come from axial resonances, with decay modes D 0 → a 1 ( 1260 ) + K - and D 0 → K 1 ( 1270 / 1400 ) + π - being prominent in D 0 → K - π + π + π - and D 0 → K + π - π - π + , respectively. Precise measurements of the lineshape parameters and couplings of the a 1 ( 1260 ) + , K 1 ( 1270 ) - and K ( 1460 ) - resonances are made, and a quasi model-independent study of the K ( 1460 ) - resonance is performed. The coherence factor of the decays is calculated from the amplitude models to be R K 3 π = 0.459 ± 0.010 ( stat ) ± 0.012 ( syst ) ± 0.020 ( model ) , which is consistent with direct measurements. These models will be useful in future measurements of the unitary-triangle angle γ and studies of charm mixing and C P violation.

Measurement of the Ratio of the B^{0}→D^{*-}τ^{+}ν_{τ} and B^{0}→D^{*-}μ^{+}ν_{μ} Branching Fractions Using Three-Prong τ-Lepton Decays

The ratio of branching fractions R(D^{*-})≡B(B^{0}→D^{*-}τ^{+}ν_{τ})/B(B^{0}→D^{*-}μ^{+}ν_{μ}) is measured using a data sample of proton-proton collisions collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3  fb^{-1}. For the first time, R(D^{*-}) is determined using the τ-lepton decays with three charged pions in the final state. The B^{0}→D^{*-}τ^{+}ν_{τ} yield is normalized to that of the B^{0}→D^{*-}π^{+}π^{-}π^{+} mode, providing a measurement of B(B^{0}→D^{*-}τ^{+}ν_{τ})/B(B^{0}→D^{*-}π^{+}π^{-}π^{+})=1.97±0.13±0.18, where the first uncertainty is statistical and the second systematic. The value of B(B^{0}→D^{*-}τ^{+}ν_{τ})=(1.42±0.094±0.129±0.054)% is obtained, where the third uncertainty is due to the limited knowledge of the branching fraction of the normalization mode. Using the well-measured branching fraction of the B^{0}→D^{*-}μ^{+}ν_{μ} decay, a value of R(D^{*-})=0.291±0.019±0.026±0.013 is established, where the third uncertainty is due to the limited knowledge of the branching fractions of the normalization and B^{0}→D^{*-}μ^{+}ν_{μ} modes. This measurement is in agreement with the standard model prediction and with previous results.

Measurement of the Ratio of Branching Fractions B(B_{c}^{+}→J/ψτ^{+}ν_{τ})/B(B_{c}^{+}→J/ψμ^{+}ν_{μ})

A measurement is reported of the ratio of branching fractions R(J/ψ)=B(B_{c}^{+}→J/ψτ^{+}ν_{τ})/B(B_{c}^{+}→J/ψμ^{+}ν_{μ}), where the τ^{+} lepton is identified in the decay mode τ^{+}→μ^{+}ν_{μ}ν[over ¯]_{τ}. This analysis uses a sample of proton-proton collision data corresponding to 3.0  fb^{-1} of integrated luminosity recorded with the LHCb experiment at center-of-mass energies of 7 and 8 TeV. A signal is found for the decay B_{c}^{+}→J/ψτ^{+}ν_{τ} at a significance of 3 standard deviations corrected for systematic uncertainty, and the ratio of the branching fractions is measured to be R(J/ψ)=0.71±0.17(stat)±0.18(syst). This result lies within 2 standard deviations above the range of central values currently predicted by the standard model.

Search for Dark Photons Produced in 13 TeV pp Collisions

Searches are performed for both promptlike and long-lived dark photons, A^{'}, produced in proton-proton collisions at a center-of-mass energy of 13 TeV, using A^{'}→μ^{+}μ^{-} decays and a data sample corresponding to an integrated luminosity of 1.6  fb^{-1} collected with the LHCb detector. The promptlike A^{'} search covers the mass range from near the dimuon threshold up to 70 GeV, while the long-lived A^{'} search is restricted to the low-mass region 214<m(A^{'})<350  MeV. No evidence for a signal is found, and 90% confidence level exclusion limits are placed on the γ-A^{'} kinetic-mixing strength. The constraints placed on promptlike dark photons are the most stringent to date for the mass range 10.6<m(A^{'})<70  GeV, and are comparable to the best existing limits for m(A^{'})<0.5  GeV. The search for long-lived dark photons is the first to achieve sensitivity using a displaced-vertex signature.

Intensification of ice nucleation observed in ocean ship emissions

Shipping contributes primary and secondary emission products to the atmospheric aerosol burden that have implications for climate, clouds, and air quality from regional to global scales. In this study we exam the potential impact of ship emissions with regards to ice nucleating particles. Particles that nucleate ice are known to directly affect precipitation and cloud microphysical properties. We have collected and analyzed particles for their ice nucleating capacity from a shipping channel outside a large Scandinavia port. We observe that ship plumes amplify the background levels of ice nucleating particles and discuss the larger scale implications. The measured ice nucleating particles suggest that the observed amplification is most likely important in regions with low levels of background particles. The Arctic, which as the sea ice pack declines is opening to transit and natural resource exploration and exploitation at an ever increasing rate, is highlighted as such a region.

First Observation of the Rare Purely Baryonic Decay B^{0}→pp[over ¯]

The first observation of the decay of a B^{0} meson to a purely baryonic final state, B^{0}→pp[over ¯], is reported. The proton-proton collision data sample used was collected with the LHCb experiment at center-of-mass energies of 7 and 8 TeV and corresponds to an integrated luminosity of 3.0  fb^{-1}. The branching fraction is determined to be B(B^{0}→pp[over ¯])=(1.25±0.27±0.18)×10^{-8}, where the first uncertainty is statistical and the second systematic. The decay mode B^{0}→pp[over ¯] is the rarest decay of the B^{0} meson observed to date. The decay B_{s}^{0}→pp[over ¯] is also investigated. No signal is seen and the upper limit B(B_{s}^{0}→pp[over ¯])<1.5×10^{-8} at 90% confidence level is set on the branching fraction.

χ_{c1} and χ_{c2} Resonance Parameters with the Decays χ_{c1,c2}→J/ψμ^{+}μ^{-}

The decays χ_{c1}→J/ψμ^{+}μ^{-} and χ_{c2}→J/ψμ^{+}μ^{-} are observed and used to study the resonance parameters of the χ_{c1} and χ_{c2} mesons. The masses of these states are measured to be m(χ_{c1})=3510.71±0.04(stat)±0.09(syst)  MeV and m(χ_{c2})=3556.10±0.06(stat)±0.11(syst)  MeV, where the knowledge of the momentum scale for charged particles dominates the systematic uncertainty. The momentum-scale uncertainties largely cancel in the mass difference m(χ_{c2})-m(χ_{c1})=45.39±0.07(stat)±0.03(syst)  MeV. The natural width of the χ_{c2} meson is measured to be Γ(χ_{c2})=2.10±0.20(stat)±0.02(syst)  MeV. These results are in good agreement with and have comparable precision to the current world averages.