1
|
A practical approach to implementing incremental haemodialysis. J Nephrol 2024:10.1007/s40620-024-01939-2. [PMID: 38763995 DOI: 10.1007/s40620-024-01939-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 03/24/2024] [Indexed: 05/21/2024]
Abstract
The majority of end-stage kidney disease patients are treated with haemodialysis (HD). Starting HD can pose physical, social, and psychological challenges to patients, and mortality rates within the first 6 months are disproportionately high, with intensive HD regimens implicated as a potential factor. Starting HD with an incremental approach, taking residual kidney function (RKF) into account, potentially allows for a gentle start with reduced dialysis intensity. Dialysis intensity (session time or frequency) can then be proportionally increased as RKF reduces. This approach to starting HD has been reported in observational studies to result in better patient self-reported health quality of life and reduced costs, and now several definitive randomised controlled trials are underway comparing an incremental approach to the conventional thrice weekly paradigm. Physician concerns over the risk of inadequate dialysis, with consequent increased emergency admissions, and practical challenges of how to estimate RKF and implement incremental dialysis have impeded widespread adoption. Addressing these challenges is paramount to increasing the uptake of incremental HD. Careful patient selection lies at the heart of a successful incremental HD programme. Generally, patients with a residual urea clearance of > 3 ml/min/1.73 m2 can be considered suitable for starting with incremental HD provided they comply with fluid intake, salt and other dietary recommendations. Calculating RKF from regular interdialytic urine collections and appropriately adjusting sessional HD clearance targets are practical and conceptual challenges. In this report we aim to disentangle these complexities and provide a step-by-step guide for patient selection and adjusting dialysis sessional targets.
Collapse
|
2
|
The Dhaka Call to Action to accelerate the control of cardiovascular diseases in South-East Asia. Nat Med 2024; 30:19-20. [PMID: 38167936 DOI: 10.1038/s41591-023-02678-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
|
3
|
Definitive Stereotactic Body Radiation Therapy in Early-Stage Solitary Hepatocellular Carcinoma: An Australian Multi-Institutional Review of Outcomes. Clin Oncol (R Coll Radiol) 2023; 35:787-793. [PMID: 37709623 DOI: 10.1016/j.clon.2023.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/08/2023] [Accepted: 08/30/2023] [Indexed: 09/16/2023]
Abstract
AIMS Standard curative options for early-stage, solitary hepatocellular carcinoma (HCC) are often unsuitable due to liver dysfunction, comorbidities and/or tumour location. Stereotactic body radiation therapy (SBRT) has shown high rates of local control in HCC; however, limited data exist in the treatment-naïve, curative-intent setting. We report the outcomes of patients with solitary early-stage HCC treated with SBRT as first-line curative-intent therapy. MATERIALS AND METHODS A multi-institutional retrospective study of treatment-naïve patients with Barcelona Clinic Liver Cancer stage 0/A, solitary ≤5 cm HCC, Child-Pugh score (CPS) A liver function who underwent SBRT between 2010 and 2019 as definitive therapy. The primary end point was freedom from local progression. Secondary end points were progression-free survival, overall survival, rate of treatment-related clinical toxicities and change in CPS >1. RESULTS In total, 68 patients were evaluated, with a median follow-up of 20 months (range 3-58). The median age was 68 years (range 50-86); 54 (79%) were men, 62 (91%) had cirrhosis and 50 (74%) were Eastern Cooperative Oncology Group 0. The median HCC diameter was 2.5 cm (range 1.3-5) and the median prescription biologically effective dose with a tumour a/b ratio of 10 Gy (BED10) was 93 Gy (interquartile range 72-100 Gy). Two-year freedom from local progression, progression-free survival and overall survival were 94.3% (95% confidence interval 86.6-100%), 59.5% (95% confidence interval 46.3-76.4%) and 88% (95% confidence interval 79.2-97.6%), respectively. Nine patients (13.2%) experienced grade ≥2 treatment-related clinical toxicities. A rise >1 in CPS was observed in six cirrhotic patients (9.6%). CONCLUSION SBRT is an effective and well-tolerated option to consider in patients with solitary, early-stage HCC. Prospective, randomised comparative studies are warranted to further refine its role as a first-line curative-intent therapy.
Collapse
|
4
|
Outcomes of Patients with Oral Cavity Squamous Cell Carcinomas Treated with Adjuvant IMRT with Perineural Invasion. Int J Radiat Oncol Biol Phys 2023; 117:e569-e570. [PMID: 37785737 DOI: 10.1016/j.ijrobp.2023.06.1898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Patients with advanced oral cavity squamous cell carcinoma (OCSCC) have high rates of recurrence and dismal outcomes. Treatment consists of definitive surgery followed by risk-adapted adjuvant radiation therapy based on pathologic review. Perineural invasion (PNI) is thought to be an intermediate risk factor, leading to clinical uncertainty as to adjuvant therapy in the setting of PNI. We performed a single institution retrospective review of patients with OCSCC treated with adjuvant radiation with or without PNI and examined relapse-free survival (RFS) and overall survival (OS). MATERIALS/METHODS We performed a single-institutional retrospective review of patients with OCSCC treated with adjuvant IMRT +/- chemotherapy after surgical resection from July 2002- August 2021 using our institution's Head and Neck SPORE database. Time to recurrence or death was calculated from end of RT. OCSCC within 5 years of RT was considered a recurrence, beyond this timeframe any OCSCC was considered a new primary. Univariate analysis of predictors for RFS and OS were performed using the Kaplan-Meier method with log-rank test. Factors significant on univariable analysis were entered into parsimonious cox multivariable analysis using forward selection methodology. A p-value <0.05 was considered significant in both analyses. RESULTS In total, 494 patients with OCSCC were identified that received surgery and adjuvant IMRT. In this cohort, 48.8% of patients had pT4 tumors, 62.2% of patients had nodal involvement, and 40.3% of patients had extranodal extension. PNI was present in 63.6% of patients (n = 314). With regards to tumor subsite, 40.9% originated from the oral tongue, 21.5% originated from the gums, 18% originated from the floor of mouth, and 19.6% from the other sites. Median age was 59 years, and median adjuvant RT dose was 63 Gy (Interquartile range [IQR]) 60-66 Gy). The majority of patient received platinum-based chemotherapy (51.8%), and 44.1% of patients did not receive adjuvant chemotherapy. The 3-year RFS and OS with a median follow-up of 32 months (IQR 12-69 months) is presented in Table 1. On univariable analysis for OS, T stage (p = 0.003), N stage (p<0.001), PNI (p = 0.005), extranodal extension (ENE) (p<0.001), margin status (p = 0.038), and chemotherapy (p<0.001) were significant. On multivariable analysis, T stage (p<0.001), N stage (p = 0.010), PNI (p = 0.017), and ENE (p = 0.007) remained significant. Similar results were seen in the RFS analysis. CONCLUSION In this large single institution study, PNI was a significant and independent negative predictive factor for RFS and OS in patients with OCSCC that had received definitive surgery followed by adjuvant IMRT. To our knowledge this is the largest study of its kind, and these findings can help guide clinical decision making for these patients.
Collapse
|
5
|
TROG 15.03/ANZUP International Multicenter Phase II Trial of Focal Ablative STereotactic RAdiotherapy for Cancers of the Kidney (FASTRACK II). Int J Radiat Oncol Biol Phys 2023; 117:S3. [PMID: 37784470 DOI: 10.1016/j.ijrobp.2023.06.208] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Stereotactic body radiotherapy (SBRT) is an emerging non-invasive alternative for primary renal cell cancer (RCC) in patients unsuitable for surgery. The objective of the FASTRACK II clinical trial was to investigate the efficacy of SBRT for primary RCC. MATERIALS/METHODS This non-randomized, intergroup multi-institutional phase II study was activated in 7 Australian centers and 1 Dutch center, through the Trans Tasman Radiation Oncology Group (TROG) and the Australian and New Zealand Urogenital and Prostate Cancer Trials Group (ANZUP). Eligible patients had biopsy confirmed diagnosis of primary RCC with a single lesion within a kidney, ECOG performance ≤2 and were medically inoperable, high risk or declined surgery. For tumors ≤4 cm a single fraction of 26 Gy was prescribed, for tumors > 4 cm, 42 Gy in three fractions was prescribed. The primary outcome of the study was to estimate the efficacy of SBRT for primary RCC, defined as local control based on RECIST criteria. The study was powered assuming that 1-year local control would be 90%, with the null hypothesis of ≤80% considered undesirable and not worthy of proceeding to a future randomized controlled trial. RESULTS Between July 2016 and February 2020, 70 patients were enrolled with a median follow-up of 42 months. Median age was 77 years. Forty-nine patients were male (70%), median BMI was 32 and median Charlson comorbidity score was 7. The median [IQR] RENAL complexity score was 8 [7-10]. Biopsy confirmation was 100%. Twenty-three patients (33%) had T1a disease. The median (interquartile range [IQR]) tumor size was 4.6cm [3.7-5.5]; it was 3.3cm [3.0-3.6] in those receiving single fraction (n = 23), and 5.3cm [4.6-6.0] in those receiving 3-fraction SBRT (n = 47). During real-time pre-treatment quality assurance review, 10 cases (14.3%) required resubmission for protocol deviation, 2119 variables were assessed at final review, and final protocol compliance was 99.3%. Seven (10%) patients experienced grade 3 treatment-related adverse events, with no grade 4 or 5 events observed. Eleven (16%) patients reported no adverse events. Local control was 100% throughout the lifetime of the trial (p<0.001). Cancer-specific survival was also 100% throughout the lifetime of the trial. Freedom from distant failure (95% CIs) at 1 and 3 years was 99% (90-100%). Overall survival (95% CIs) at 1 and 3 years was 99% (90-100%) and 82% (70-89%), respectively. Baseline mean eGFR (95% CI) was 61.1 mLs/min (56.6; 65.6) and reduced by -10.8 mLs/min (-13.0; -8.6) by 1-year, by -14.6 mLs/min (-17.0; -12.2) by 2-years and plateaued thereafter. CONCLUSION In the first multicenter prospective trial of a non-surgical primary RCC cohort, enrolling mostly T1b+ disease, SBRT was an effective treatment strategy with no observed local failures. We observed an acceptable side effect profile and renal function after SBRT. These outcomes support the design of a future randomized clinical trial of SBRT versus surgery for primary RCC. The trial was registered with ID: NCT02613819.
Collapse
|
6
|
Robust energy management technique for plug-in hybrid electric vehicle with traffic condition identification. Appl Soft Comput 2022. [DOI: 10.1016/j.asoc.2022.109937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
7
|
Response to neoadjuvant targeted therapy in operable head and neck cancer confers survival benefit. Eur J Cancer 2022. [DOI: 10.1016/s0959-8049(22)01141-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
8
|
PO-1871 Viscous Aqueous Gel Illustrating Natural Anatomy; the VAGINA method in gynaecological MRI simulation. Radiother Oncol 2022. [DOI: 10.1016/s0167-8140(22)03834-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
9
|
Emergency Dynamic Central Venous Cannulation in Preterm Neonates- A Case Series. J Clin Diagn Res 2022. [DOI: 10.7860/jcdr/2022/59109.16868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Neonatal venous cannulation is one of the challenges faced by Anaesthesiologists in routine practice. Neonatal cannulation is extremely difficult and time consuming and it has become an inevitable procedure in neonatal intensive care unit, because of the small vessel diameter and sometimes it is impossible to differentiate between artery and vein. Routinely umbilical vein, scalp vein and peripherally inserted central catheters cannulation are done during initial neonatal period. Central vein cannulation is needed in sick neonates for nutrition, antibiotics, venous sampling, and inotropic support and enables haemodynamics monitoring. Even with the point of care ultrasound, neonatal cannulation is technically challenging in well-experienced hands. Cannulation in a preterm neonate is highly demanding and nightmarish for all intensivists. The present case series aimed to show the successful placement of ultrasound guided supraclavicular subclavian cannulation in a very low birth preterm (less than 1500 gm) in three septic neonates. All three cannulations were done bedside in Neonatal Intensive Care Unit (NICU) with close monitoring of heart rate, pulse oximeter and electrocardiogram. Venipuncture was done under ultrasound guidance. After identifying the anatomic landmarks, subclavian cannulation was done using Seldinger technique. Subclavian cannulation was preferred because of easy accessibility, comfortable fixation and low infection rate
Collapse
|
10
|
An unusual presentation of an adrenal tumour-a case report. Int J Surg Case Rep 2021; 89:106662. [PMID: 34894595 PMCID: PMC8668818 DOI: 10.1016/j.ijscr.2021.106662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION AND IMPORTANCE Adrenal myelolipomas are rare, benign tumours with an incidence of 0.08-0.2%. They present between the fifth and seventh decade of life [1]. CASE PRESENTATION Our patient presented with complaints of vomiting and left lumbar pain of four weeks duration. Blood work revealed dyselectrolytemia. Contrast enhanced computed tomography of the abdomen and pelvis confirmed the diagnosis and the patient was planned for an adrenalectomy. Histopathology report revealed the pathology. She is currently on routine follow up and is disease free. Written informed consent was obtained from the patient for publication of this case report and its accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request. This case report has been reported in line with the SCARE criteria [2]. CLINICAL DISCUSSION With the increased use of imaging modalities of the abdomen, they are now considered to be the second most common cause of adrenal incidentalomas (6-16%) [3]. Most tumours are small, asymptomatic and often go undiagnosed. Large tumours can cause chronic pain and other nonspecific symptoms. CONCLUSION Though myelolipomas are identified on routine CT scans, on a background of dyselectrolytemia, a further evaluation is of utmost importance to rule out the possibility of a functioning tumour.
Collapse
|
11
|
691TiP A phase III, randomized study of enzalutamide (ENZA) plus leuprolide (LHRHa), ENZA monotherapy, and placebo plus LHRHa in men with high-risk nonmetastatic hormone-sensitive prostate cancer (nmHSPC) progressing after local therapy: EMBARK final protocol/study status. Ann Oncol 2020. [DOI: 10.1016/j.annonc.2020.08.2085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
12
|
Comprehensive Study on Tropical (10°N-15°N) Mesospheric Inversion Layers Using Lidar and Satellite (Timed-Saber) Observations. EPJ WEB OF CONFERENCES 2020. [DOI: 10.1051/epjconf/202023704001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
One of the interesting and poorly understood features of mesosphere and lower thermosphere (MLT) region is the phenomenon of Mesospheric Inversion Layers (MILs). The poor understanding of MILs is due to limited access of their occurrence height region, however the lidars are more efficient tools which provide stratosphere and mesosphere nocturnal temperatures with high temporal and vertical resolutions. The state-of-the-art lidar system comprising Mie, Rayleigh lidars installed at National Atmospheric Research Laboratory (NARL), Gadanki (13.5°N, 79.2°E), India has provided an excellent opportunity to undertake this study. The Nd:YAG laser source with lower power (11W) has been replaced by the one with higher power (30W) in January 2007. As the laser power has been increased, the molecular back scatter signal is also increased and consequently the top height level of the temperature retrieval has been increased to ~90-95 km. In the present study, the role of dominant causative mechanisms for the occurrence of MILs has been discussed using mainly the lidar and satellite (TIMED-SABER) observations over Gadanki region.
Collapse
|
13
|
Malignant peripheral nerve sheath tumour-A case report. Int J Surg Case Rep 2019; 64:161-164. [PMID: 31670144 PMCID: PMC6831800 DOI: 10.1016/j.ijscr.2019.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/22/2019] [Accepted: 10/02/2019] [Indexed: 11/27/2022] Open
Abstract
Pre-sacral mass presenting with right thigh shooting pain in the setting of Von Recklinghausen. Radiological imaging was crucial in providing a road map pre-op. Mass abutting the internal iliac artery and possibly pressing on the sacral nerve roots.
Introduction Malignant peripheral nerve sheath tumors (MPNST) are rare, aggressive sarcomatous tumors that arise from peripheral nerve sheaths and show schwann cell differentiation (Thangadurai, 2017) [1]. They commonly arise among patients with neurofibromatosis I and following radiation therapy (Farid et al., 2014). High resolution PET scans confirm the diagnosis and the definitive treatment is surgical excision. Post operative radiotherapy plays an important role in disease free survival rates. Chemotherapy is offered to people who have a systemic disease. Presentation of case This case report is on a 47 year old lady, a known case of Von Recklinghausen, who complained of a vague mass in the pelvis with recent history of pain to her right thigh. Pelvic examination revealed a vague mass on the right side of her pelvis. She was planned for excision of the mass. Intraoperative findings were consistent with the clinical and radiological findings. She is currently on regular follow-up and disease free. Discussion MPNSTs are rare tumours that arise in patients with neurofibromatosis I. Mutations at the genetic level is responsible for the development of MPNST. Early presentation, radiological confirmation, aggressive margin free surgery followed by chemoradiation helps in near complete cure of the disease. Conclusion MPNST are difficult to manage because of their aggressive nature and the limitations in early diagnosis and management. In patients with Von Recklinghausens disease, malignancy must be suspected when a patient presents with the complaints as mentioned in this case report.
Collapse
|
14
|
Lessons learned from a comprehensive electronic patient record procurement process-implications for healthcare organisations. BMJ Health Care Inform 2019; 26:bmjhci-2019-000020. [PMID: 31072821 PMCID: PMC7062322 DOI: 10.1136/bmjhci-2019-000020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 02/19/2019] [Accepted: 02/27/2019] [Indexed: 11/21/2022] Open
Abstract
Background This study describes learning from procurement of a comprehensive electronic patient record (EPR/electronic health record (EHR)), system for a specialist clinical academic institution. Method Retrospective review of procurement process in addition to evaluation of peer-reviewed literature in the field. Results Main lessons learned include the importance of detailed preparation of organisational requirements/specifications and organisational ‘readiness’. Early staff involvement, resulting in ownership of the selected system by the organisation was a key achievement. The scoring process used required significant resource commitment but, despite being extensive in scope, provided relatively poor distinction between suppliers, despite significant variation in supplier self-scoring. Other elements, such as demonstrations and site visits, provided superior evaluation of functional abilities, and specification requirements should be regarded as threshold evaluation. Conclusion While principles should be followed, the procurement process must be modified to meet the needs of the specific organisation, in terms of its clinical activities, digital maturity, existing infrastructure and budget.
Collapse
|
15
|
EP-1454 Multi-parametric MRI as a biomarker in anal cancer: a prospective trial. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31874-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
16
|
EP-1455 Post chemoradiotherapy FDG-PET parameters predict for recurrence in anal cancer: a prospective trial. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31875-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
17
|
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^{+}. PHYSICAL REVIEW LETTERS 2018; 120:261801. [PMID: 30004725 DOI: 10.1103/physrevlett.120.261801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/15/2018] [Indexed: 06/08/2023]
Abstract
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.
Collapse
|
18
|
Studies of the resonance structure in D 0 → K ∓ π ± π ± π ∓ decays. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:443. [PMID: 30956546 PMCID: PMC6417441 DOI: 10.1140/epjc/s10052-018-5758-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 03/23/2018] [Indexed: 06/09/2023]
Abstract
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.
Collapse
|
19
|
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. PHYSICAL REVIEW LETTERS 2018; 120:171802. [PMID: 29756810 DOI: 10.1103/physrevlett.120.171802] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 03/05/2018] [Indexed: 06/08/2023]
Abstract
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.
Collapse
|
20
|
Determination of thiamethoxam residues in banana stem and fruit through LC-MS/MS. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:293. [PMID: 29671070 DOI: 10.1007/s10661-018-6655-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 04/02/2018] [Indexed: 06/08/2023]
Abstract
An analytical method based on liquid chromatography coupled with mass spectroscopy/mass spectroscopy was developed and validated for the determination of thiamethoxam residues in banana fruit and stem tissue samples. In this study, Waters Alliance LC and Acquity TQD were used with an electrospray ionization interface in the positive ion mode. An isocratic flow of 0.5% HCOOH in water and 0.05% HCOOH in CH3CN was used for separation. Thiamethoxam residue was extracted from the samples using CH3CN and a dispersive solid-phase extraction method was used for subsequent cleanup. Linearity studies were conducted between 0.001 and 0.1 μg mL-1 of standard solution with three replicates for each concentration. Satisfactory recoveries (107.21 to 115.16% and 90.94 to 109.22%) and high precision (relative standard deviations of 3.71 to 12.83% and 3.24 to 10.78%) were obtained for the banana stem and banana fruit matrix, respectively. The lower limits of detection and quantification achieved were 0.002 and 0.008 μg g-1 for banana stem and 0.001and 0.005 μg g-1for banana fruit, respectively. The developed method was used to analyze the banana stem and fruit samples collected from thiamethoxam-treated fields and stems from the local market.
Collapse
|
21
|
Measurement of the Ratio of Branching Fractions B(B_{c}^{+}→J/ψτ^{+}ν_{τ})/B(B_{c}^{+}→J/ψμ^{+}ν_{μ}). PHYSICAL REVIEW LETTERS 2018; 120:121801. [PMID: 29694106 DOI: 10.1103/physrevlett.120.121801] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 01/19/2018] [Indexed: 06/08/2023]
Abstract
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.
Collapse
|
22
|
Search for Dark Photons Produced in 13 TeV pp Collisions. PHYSICAL REVIEW LETTERS 2018; 120:061801. [PMID: 29481252 DOI: 10.1103/physrevlett.120.061801] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Indexed: 06/08/2023]
Abstract
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.
Collapse
|
23
|
Rayleigh lidar observation of tropical mesospheric inversion layer: a comparison between dynamics and chemistry. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201817603003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Rayleigh lidar at National Atmospheric Research Laboratory, Gadanki (13.5°N, 79.2°E), India operates at 532 nm green laser with ~600 mJ/pulse since 2007. The vertical temperature profiles are derived above ~30 km by assuming the atmosphere is in hydrostatic equilibrium and obeys ideal gas law. A large mesospheric inversion layer (MIL) is observed at ~77.4-84.6 km on the night of 22 March 2007 over Gadanki. Although dynamics and chemistry play vital role, both the mechanisms are compared for the occurrence of the MIL in the present study.
Collapse
|
24
|
Abstract
C5a is a potent anaphylatoxin that modulates inflammation through the C5aR1 and C5aR2 receptors. The molecular interactions between C5a-C5aR1 receptor are well defined, whereas C5a-C5aR2 receptor interactions are poorly understood. Here, we describe the generation of a human antibody, MEDI7814, that neutralizes C5a and C5adesArg binding to the C5aR1 and C5aR2 receptors, without affecting complement-mediated bacterial cell killing. Unlike other anti-C5a mAbs described, this antibody has been shown to inhibit the effects of C5a by blocking C5a binding to both C5aR1 and C5aR2 receptors. The crystal structure of the antibody in complex with human C5a reveals a discontinuous epitope of 22 amino acids. This is the first time the epitope for an antibody that blocks C5aR1 and C5aR2 receptors has been described, and this work provides a basis for molecular studies aimed at further understanding the C5a-C5aR2 receptor interaction. MEDI7814 has therapeutic potential for the treatment of acute inflammatory conditions in which both C5a receptors may mediate inflammation, such as sepsis or renal ischemia-reperfusion injury.
Collapse
MESH Headings
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/genetics
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- Antibody Affinity
- Antibody Specificity
- Binding Sites, Antibody
- Complement C5a/antagonists & inhibitors
- Complement C5a/chemistry
- Complement C5a/immunology
- Complement C5a/metabolism
- Epitope Mapping/methods
- Epitopes
- HEK293 Cells
- Humans
- Protein Binding
- Protein Conformation
- Protein Engineering
- Receptor, Anaphylatoxin C5a/antagonists & inhibitors
- Receptor, Anaphylatoxin C5a/chemistry
- Receptor, Anaphylatoxin C5a/immunology
- Receptor, Anaphylatoxin C5a/metabolism
- Receptors, Chemokine/antagonists & inhibitors
- Receptors, Chemokine/chemistry
- Receptors, Chemokine/immunology
- Receptors, Chemokine/metabolism
- Structure-Activity Relationship
Collapse
|
25
|
First Observation of the Rare Purely Baryonic Decay B^{0}→pp[over ¯]. PHYSICAL REVIEW LETTERS 2017; 119:232001. [PMID: 29286678 DOI: 10.1103/physrevlett.119.232001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Indexed: 06/07/2023]
Abstract
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.
Collapse
|
26
|
χ_{c1} and χ_{c2} Resonance Parameters with the Decays χ_{c1,c2}→J/ψμ^{+}μ^{-}. PHYSICAL REVIEW LETTERS 2017; 119:221801. [PMID: 29286773 DOI: 10.1103/physrevlett.119.221801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Indexed: 06/07/2023]
Abstract
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.
Collapse
|
27
|
Updated search for long-lived particles decaying to jet pairs. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:812. [PMID: 31997934 PMCID: PMC6956870 DOI: 10.1140/epjc/s10052-017-5178-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/31/2017] [Indexed: 06/10/2023]
Abstract
A search is presented for long-lived particles with a mass between 25 and 50 GeV / c 2 and a lifetime between 2 and 500 ps, using proton-proton collision data corresponding to an integrated luminosity of 2.0 fb - 1 , collected by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. The particles are assumed to be pair-produced in the decay of a 125 GeV / c 2 Standard-Model-like Higgs boson. The experimental signature is a single long-lived particle, identified by a displaced vertex with two associated jets. No excess above background is observed and limits are set on the production cross-section as a function of the mass and lifetime of the long-lived particle.
Collapse
|
28
|
Abstract
Complementarity-determining regions (CDRs) are antibody loops that make up the antigen binding site. Here, we show that all CDR types have structurally similar loops of different lengths. Based on these findings, we created length-independent canonical classes for the non-H3 CDRs. Our length variable structural clusters show strong sequence patterns suggesting either that they evolved from the same original structure or result from some form of convergence. We find that our length-independent method not only clusters a larger number of CDRs, but also predicts canonical class from sequence better than the standard length-dependent approach. To demonstrate the usefulness of our findings, we predicted cluster membership of CDR-L3 sequences from 3 next-generation sequencing datasets of the antibody repertoire (over 1,000,000 sequences). Using the length-independent clusters, we can structurally classify an additional 135,000 sequences, which represents a ∼20% improvement over the standard approach. This suggests that our length-independent canonical classes might be a highly prevalent feature of antibody space, and could substantially improve our ability to accurately predict the structure of novel CDRs identified by next-generation sequencing.
Collapse
|
29
|
Observation of D^{0} Meson Decays to π^{+}π^{-}μ^{+}μ^{-} and K^{+}K^{-}μ^{+}μ^{-} Final States. PHYSICAL REVIEW LETTERS 2017; 119:181805. [PMID: 29219589 DOI: 10.1103/physrevlett.119.181805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Indexed: 06/07/2023]
Abstract
The first observation of the D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} decays is reported using a sample of proton-proton collisions collected by LHCb at a center-of-mass energy of 8 TeV, and corresponding to 2 fb^{-1} of integrated luminosity. The corresponding branching fractions are measured using as normalization the decay D^{0}→K^{-}π^{+}[μ^{+}μ^{-}]_{ρ^{0}/ω}, where the two muons are consistent with coming from the decay of a ρ^{0} or ω meson. The results are B(D^{0}→π^{+}π^{-}μ^{+}μ^{-})=(9.64±0.48±0.51±0.97)×10^{-7} and B(D^{0}→K^{+}K^{-}μ^{+}μ^{-})=(1.54±0.27±0.09±0.16)×10^{-7}, where the uncertainties are statistical, systematic, and due to the limited knowledge of the normalization branching fraction. The dependence of the branching fraction on the dimuon mass is also investigated.
Collapse
|
30
|
Search for Baryon-Number Violating Ξ_{b}^{0} Oscillations. PHYSICAL REVIEW LETTERS 2017; 119:181807. [PMID: 29219549 DOI: 10.1103/physrevlett.119.181807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Indexed: 06/07/2023]
Abstract
A search for baryon-number violating Ξ_{b}^{0} oscillations is performed with a sample of pp collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 3 fb^{-1}. The baryon number at the moment of production is identified by requiring that the Ξ_{b}^{0} come from the decay of a resonance Ξ_{b}^{*-}→Ξ_{b}^{0}π^{-} or Ξ_{b}^{'-}→Ξ_{b}^{0}π^{-}, and the baryon number at the moment of decay is identified from the final state using the decays Ξ_{b}^{0}→Ξ_{c}^{+}π^{-},Ξ_{c}^{+}→pK^{-}π^{+}. No evidence of baryon-number violation is found, and an upper limit at the 95% confidence level is set on the oscillation rate of ω<0.08 ps^{-1}, where ω is the associated angular frequency.
Collapse
|
31
|
Sanitation marketing: A systematic review and theoretical critique using the capability approach. Soc Sci Med 2017; 194:128-134. [PMID: 29100137 DOI: 10.1016/j.socscimed.2017.10.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/03/2017] [Accepted: 10/17/2017] [Indexed: 11/17/2022]
Abstract
Sanitation is a human right that benefits health. As such, technical and behavioural interventions are widely implemented to increase the number of people using sanitation facilities. These include sanitation marketing interventions (SMIs), in which external support agencies (ESAs) use a hybrid of commercial and social marketing tools to increase supply of, and demand for, sanitation products and services. However, there is little critical discourse on SMIs, or independent rigorous analysis on whether they increase or reduce well-being. Most available information is from ESAs about their own SMI implementation. We systematically reviewed the grey and peer-reviewed literature on sanitation marketing, including qualitatively analysing and calculating descriptive statistics for the parameters measured, or intended to be measured, in publications reporting on 33 SMIs. Guided by the capability approach to development we identified that publications for most SMIs (n = 31, 94%) reported on commodities, whilst fewer reported on parameters related to impacts on well-being (i.e., functionings, n = 22, 67%, and capabilities, n = 20, 61%). When evaluating future SMIs, it may be useful to develop a list of contextualised well-being indicators for the particular SMI's location, taking into account local cultural norms, with this list ideally co-produced with local stakeholders. We identified two common practices in SMIs that can reduce well-being and widen well-being inequalities; namely, the promotion of conspicuous consumption and assaults on dignity, and we discuss the mechanisms by which such impacts occur. We recommend that ESAs understand sanitation marketing's potential to reduce well-being and design SMIs to minimize such detrimental impacts. Throughout the implementation phase ESAs should continuously monitor for well-being impacts and adapt practices to optimise well-being outcomes for all involved.
Collapse
|
32
|
Improved limit on the branching fraction of the rare decay K S 0 → μ + μ - . THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:678. [PMID: 31997922 PMCID: PMC6956924 DOI: 10.1140/epjc/s10052-017-5230-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 09/18/2017] [Indexed: 06/10/2023]
Abstract
A search for the decay K S 0 → μ + μ - is performed, based on a data sample of proton-proton collisions corresponding to an integrated luminosity of 3 fb - 1 , collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV . The observed yield is consistent with the background-only hypothesis, yielding a limit on the branching fraction of B ( K S 0 → μ + μ - ) < 0.8 ( 1.0 ) × 10 - 9 at 90 % ( 95 % ) confidence level. This result improves the previous upper limit on the branching fraction by an order of magnitude.
Collapse
|
33
|
Observation of the Doubly Charmed Baryon Ξ_{cc}^{++}. PHYSICAL REVIEW LETTERS 2017; 119:112001. [PMID: 28949228 DOI: 10.1103/physrevlett.119.112001] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Indexed: 06/07/2023]
Abstract
A highly significant structure is observed in the Λ_{c}^{+}K^{-}π^{+}π^{+} mass spectrum, where the Λ_{c}^{+} baryon is reconstructed in the decay mode pK^{-}π^{+}. The structure is consistent with originating from a weakly decaying particle, identified as the doubly charmed baryon Ξ_{cc}^{++}. The difference between the masses of the Ξ_{cc}^{++} and Λ_{c}^{+} states is measured to be 1334.94±0.72(stat.)±0.27(syst.) MeV/c^{2}, and the Ξ_{cc}^{++} mass is then determined to be 3621.40±0.72(stat.)±0.27(syst.)±0.14(Λ_{c}^{+}) MeV/c^{2}, where the last uncertainty is due to the limited knowledge of the Λ_{c}^{+} mass. The state is observed in a sample of proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.7 fb^{-1}, and confirmed in an additional sample of data collected at 8 TeV.
Collapse
|
34
|
Study of charmonium production in b -hadron decays and first evidence for the decay B s 0 → ϕ ϕ ϕ. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:609. [PMID: 31997939 PMCID: PMC6956955 DOI: 10.1140/epjc/s10052-017-5151-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 08/20/2017] [Indexed: 06/10/2023]
Abstract
Using decays to ϕ -meson pairs, the inclusive production of charmonium states in b -hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0 fb - 1 , collected by the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. Denoting by B C ≡ B ( b → C X ) × B ( C → ϕ ϕ ) the inclusive branching fraction of a b hadron to a charmonium state C that decays into a pair of ϕ mesons, ratios R C 2 C 1 ≡ B C 1 / B C 2 are determined as R η c ( 1 S ) χ c 0 = 0.147 ± 0.023 ± 0.011 , R η c ( 1 S ) χ c 1 = 0.073 ± 0.016 ± 0.006 , R η c ( 1 S ) χ c 2 = 0.081 ± 0.013 ± 0.005 , R χ c 0 χ c 1 = 0.50 ± 0.11 ± 0.01 , R χ c 0 χ c 2 = 0.56 ± 0.10 ± 0.01 and R η c ( 1 S ) η c ( 2 S ) = 0.040 ± 0.011 ± 0.004 . Here and below the first uncertainties are statistical and the second systematic. Upper limits at 90% confidence level for the inclusive production of X(3872), X(3915) and χ c 2 ( 2 P ) states are obtained as R χ c 1 X ( 3872 ) < 0.34 , R χ c 0 X ( 3915 ) < 0.12 and R χ c 2 χ c 2 ( 2 P ) < 0.16 . Differential cross-sections as a function of transverse momentum are measured for the η c ( 1 S ) and χ c states. The branching fraction of the decay B s 0 → ϕ ϕ ϕ is measured for the first time, B ( B s 0 → ϕ ϕ ϕ ) = ( 2.15 ± 0.54 ± 0.28 ± 0 . 21 B ) × 10 - 6 . Here the third uncertainty is due to the branching fraction of the decay B s 0 → ϕ ϕ , which is used for normalization. No evidence for intermediate resonances is seen. A preferentially transverse ϕ polarization is observed. The measurements allow the determination of the ratio of the branching fractions for the η c ( 1 S ) decays to ϕ ϕ and p p ¯ as B ( η c ( 1 S ) → ϕ ϕ ) / B ( η c ( 1 S ) → p p ¯ ) = 1.79 ± 0.14 ± 0.32 .
Collapse
|
35
|
Measurement of B_{s}^{0} and D_{s}^{-} Meson Lifetimes. PHYSICAL REVIEW LETTERS 2017; 119:101801. [PMID: 28949189 DOI: 10.1103/physrevlett.119.101801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Indexed: 06/07/2023]
Abstract
We report on a measurement of the flavor-specific B_{s}^{0} lifetime and of the D_{s}^{-} lifetime using proton-proton collisions at center-of-mass energies of 7 and 8 TeV, collected by the LHCb experiment and corresponding to 3.0 fb^{-1} of integrated luminosity. Approximately 407 000 B_{s}^{0}→D_{s}^{(*)-}μ^{+}ν_{μ} decays are partially reconstructed in the K^{+}K^{-}π^{-}μ^{+} final state. The B_{s}^{0} and D_{s}^{-} natural widths are determined using, as a reference, kinematically similar B^{0}→D^{(*)-}μ^{+}ν_{μ} decays reconstructed in the same final state. The resulting differences between widths of B_{s}^{0} and B^{0} mesons and of D_{s}^{-} and D^{-} mesons are Δ_{Γ}(B)=-0.0115±0.0053(stat)±0.0041(syst) ps^{-1} and Δ_{Γ}(D)=1.0131±0.0117(stat)±0.0065(syst) ps^{-1}, respectively. Combined with the known B^{0} and D^{-} lifetimes, these yield the flavor-specific B_{s}^{0} lifetime, τ_{B_{s}^{0}}^{fs}=1.547±0.013(stat)±0.010(syst)±0.004(τ_{B}) ps and the D_{s}^{-} lifetime, τ_{D_{s}^{-}}=0.5064±0.0030(stat)±0.0017(syst)±0.0017(τ_{D}) ps. The last uncertainties originate from the limited knowledge of the B^{0} and D^{-} lifetimes. The results improve upon current determinations.
Collapse
|
36
|
Observation of the Decays Λ_{b}^{0}→χ_{c1}pK^{-} and Λ_{b}^{0}→χ_{c2}pK^{-}. PHYSICAL REVIEW LETTERS 2017; 119:062001. [PMID: 28949591 DOI: 10.1103/physrevlett.119.062001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Indexed: 06/07/2023]
Abstract
The first observation of the decays Λ_{b}^{0}→χ_{c1}pK^{-} and Λ_{b}^{0}→χ_{c2}pK^{-} is reported using a data sample corresponding to an integrated luminosity of 3.0 fb^{-1}, collected by the LHCb experiment in pp collisions at center-of-mass energies of 7 and 8 TeV. The following ratios of branching fractions are measured: B(Λ_{b}^{0}→χ_{c1}pK^{-})/B(Λ_{b}^{0}→J/ψpK^{-})=0.242±0.014±0.013±0.009,B(Λ_{b}^{0}→χ_{c2}pK^{-})/B(Λ_{b}^{0}→J/ψpK^{-})=0.248±0.020±0.014±0.009,B(Λ_{b}^{0}→χ_{c2}pK^{-})/B(Λ_{b}^{0}→χ_{c1}pK^{-})=1.02±0.10±0.02±0.05,where the first uncertainty is statistical, the second systematic, and the third due to the uncertainty on the branching fractions of the χ_{c1}→J/ψγ and χ_{c2}→J/ψγ decays. Using both decay modes, the mass of the Λ_{b}^{0} baryon is also measured to be m_{Λ_{b}^{0}}=5619.44±0.28±0.26 MeV/c^{2}, where the first and second uncertainties are statistical and systematic, respectively.
Collapse
|
37
|
First Observation of a Baryonic B_{s}^{0} Decay. PHYSICAL REVIEW LETTERS 2017; 119:041802. [PMID: 29341762 DOI: 10.1103/physrevlett.119.041802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Indexed: 06/07/2023]
Abstract
We report the first observation of a baryonic B_{s}^{0} decay, B_{s}^{0}→pΛ[over ¯]K^{-}, using proton-proton collision data recorded by the LHCb experiment at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3.0 fb^{-1}. The branching fraction is measured to be B(B_{s}^{0}→pΛ[over ¯]K^{-})+B(B_{s}^{0}→p[over ¯]ΛK^{+})=[5.46±0.61±0.57±0.50(B)±0.32(f_{s}/f_{d})]×10^{-6}, where the first uncertainty is statistical and the second systematic, the third uncertainty accounts for the experimental uncertainty on the branching fraction of the B^{0}→pΛ[over ¯]π^{-} decay used for normalization, and the fourth uncertainty relates to the knowledge of the ratio of b-quark hadronization probabilities f_{s}/f_{d}.
Collapse
|
38
|
Measurement of the CP Violation Parameter A_{Γ} in D^{0}→K^{+}K^{-} and D^{0}→π^{+}π^{-} Decays. PHYSICAL REVIEW LETTERS 2017; 118:261803. [PMID: 28707946 DOI: 10.1103/physrevlett.118.261803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Indexed: 06/07/2023]
Abstract
Asymmetries in the time-dependent rates of D^{0}→K^{+}K^{-} and D^{0}→π^{+}π^{-} decays are measured in a pp collision data sample collected with the LHCb detector during LHC Run 1, corresponding to an integrated luminosity of 3 fb^{-1}. The asymmetries in effective decay widths between D^{0} and D[over ¯]^{0} decays, sensitive to indirect CP violation, are measured to be A_{Γ}(K^{+}K^{-})=(-0.30±0.32±0.10)×10^{-3} and A_{Γ}(π^{+}π^{-})=(0.46±0.58±0.12)×10^{-3}, where the first uncertainty is statistical and the second systematic. These measurements show no evidence for CP violation and improve on the precision of the previous best measurements by nearly a factor of two.
Collapse
|
39
|
Search for the Decays B_{s}^{0}→τ^{+}τ^{-} and B^{0}→τ^{+}τ^{-}. PHYSICAL REVIEW LETTERS 2017; 118:251802. [PMID: 28696756 DOI: 10.1103/physrevlett.118.251802] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Indexed: 06/07/2023]
Abstract
A search for the rare decays B_{s}^{0}→τ^{+}τ^{-} and B^{0}→τ^{+}τ^{-} is performed using proton-proton collision data collected with the LHCb detector. The data sample corresponds to an integrated luminosity of 3 fb^{-1} collected in 2011 and 2012. The τ leptons are reconstructed through the decay τ^{-}→π^{-}π^{+}π^{-}ν_{τ}. Assuming no contribution from B^{0}→τ^{+}τ^{-} decays, an upper limit is set on the branching fraction B(B_{s}^{0}→τ^{+}τ^{-})<6.8×10^{-3} at the 95% confidence level. If instead no contribution from B_{s}^{0}→τ^{+}τ^{-} decays is assumed, the limit is B(B^{0}→τ^{+}τ^{-})<2.1×10^{-3} at the 95% confidence level. These results correspond to the first direct limit on B(B_{s}^{0}→τ^{+}τ^{-}) and the world's best limit on B(B^{0}→τ^{+}τ^{-}).
Collapse
|
40
|
Abstract
The production of J/ψ mesons in jets is studied in the forward region of proton-proton collisions using data collected with the LHCb detector at a center-of-mass energy of 13 TeV. The fraction of the jet transverse momentum carried by the J/ψ meson, z(J/ψ)≡p_{T}(J/ψ)/p_{T}(jet), is measured using jets with p_{T}(jet)>20 GeV in the pseudorapidity range 2.5<η(jet)<4.0. The observed z(J/ψ) distribution for J/ψ mesons produced in b-hadron decays is consistent with expectations. However, the results for prompt J/ψ production do not agree with predictions based on fixed-order nonrelativistic QCD. This is the first measurement of the p_{T} fraction carried by prompt J/ψ mesons in jets at any experiment.
Collapse
|
41
|
Measurement of the B_{s}^{0}→μ^{+}μ^{-} Branching Fraction and Effective Lifetime and Search for B^{0}→μ^{+}μ^{-} Decays. PHYSICAL REVIEW LETTERS 2017; 118:191801. [PMID: 28548525 DOI: 10.1103/physrevlett.118.191801] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Indexed: 06/07/2023]
Abstract
A search for the rare decays B_{s}^{0}→μ^{+}μ^{-} and B^{0}→μ^{+}μ^{-} is performed at the LHCb experiment using data collected in pp collisions corresponding to a total integrated luminosity of 4.4 fb^{-1}. An excess of B_{s}^{0}→μ^{+}μ^{-} decays is observed with a significance of 7.8 standard deviations, representing the first observation of this decay in a single experiment. The branching fraction is measured to be B(B_{s}^{0}→μ^{+}μ^{-})=(3.0±0.6_{-0.2}^{+0.3})×10^{-9}, where the first uncertainty is statistical and the second systematic. The first measurement of the B_{s}^{0}→μ^{+}μ^{-} effective lifetime, τ(B_{s}^{0}→μ^{+}μ^{-})=2.04±0.44±0.05 ps, is reported. No significant excess of B^{0}→μ^{+}μ^{-} decays is found, and a 95% confidence level upper limit, B(B^{0}→μ^{+}μ^{-})<3.4×10^{-10}, is determined. All results are in agreement with the standard model expectations.
Collapse
|
42
|
Observation of Five New Narrow Ω_{c}^{0} States Decaying to Ξ_{c}^{+}K^{-}. PHYSICAL REVIEW LETTERS 2017; 118:182001. [PMID: 28524669 DOI: 10.1103/physrevlett.118.182001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Indexed: 06/07/2023]
Abstract
The Ξ_{c}^{+}K^{-} mass spectrum is studied with a sample of pp collision data corresponding to an integrated luminosity of 3.3 fb^{-1}, collected by the LHCb experiment. The Ξ_{c}^{+} is reconstructed in the decay mode pK^{-}π^{+}. Five new, narrow excited Ω_{c}^{0} states are observed: the Ω_{c}(3000)^{0}, Ω_{c}(3050)^{0}, Ω_{c}(3066)^{0}, Ω_{c}(3090)^{0}, and Ω_{c}(3119)^{0}. Measurements of their masses and widths are reported.
Collapse
|
43
|
Search for massive long-lived particles decaying semileptonically in the LHCb detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:224. [PMID: 28515664 PMCID: PMC5408995 DOI: 10.1140/epjc/s10052-017-4744-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 03/07/2017] [Indexed: 06/07/2023]
Abstract
A search is presented for massive long-lived particles decaying into a muon and two quarks. The dataset consists of proton-proton interactions at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of 1 and 2[Formula: see text], respectively. The analysis is performed assuming a set of production mechanisms with simple topologies, including the production of a Higgs-like particle decaying into two long-lived particles. The mass range from 20 to 80 [Formula: see text] and lifetimes from 5 to 100[Formula: see text] are explored. Results are also interpreted in terms of neutralino production in different R-Parity violating supersymmetric models, with masses in the 23-198 GeV/[Formula: see text] range. No excess above the background expectation is observed and upper limits are set on the production cross-section for various points in the parameter space of theoretical models.
Collapse
|
44
|
Observation of B_{c}^{+}→D^{0}K^{+} Decays. PHYSICAL REVIEW LETTERS 2017; 118:111803. [PMID: 28368647 DOI: 10.1103/physrevlett.118.111803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Indexed: 06/07/2023]
Abstract
Using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb^{-1}, recorded by the LHCb detector at center-of-mass energies of 7 and 8 TeV, the B_{c}^{+}→D^{0}K^{+} decay is observed with a statistical significance of 5.1 standard deviations. By normalizing to B^{+}→D[over ¯]^{0}π^{+} decays, a measurement of the branching fraction multiplied by the production rates for B_{c}^{+} relative to B^{+} mesons in the LHCb acceptance is obtained, R_{D^{0}K}=(f_{c}/f_{u})×B(B_{c}^{+}→D^{0}K^{+})=(9.3_{-2.5}^{+2.8}±0.6)×10^{-7}, where the first uncertainty is statistical and the second is systematic. This decay is expected to proceed predominantly through weak annihilation and penguin amplitudes, and is the first B_{c}^{+} decay of this nature to be observed.
Collapse
|
45
|
Measurement of the phase difference between short- and long-distance amplitudes in the [Formula: see text] decay. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:161. [PMID: 28408857 PMCID: PMC5368951 DOI: 10.1140/epjc/s10052-017-4703-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/16/2017] [Indexed: 06/07/2023]
Abstract
A measurement of the phase difference between the short- and long-distance contributions to the [Formula: see text] decay is performed by analysing the dimuon mass distribution. The analysis is based on pp collision data corresponding to an integrated luminosity of 3[Formula: see text] collected by the LHCb experiment in 2011 and 2012. The long-distance contribution to the [Formula: see text] decay is modelled as a sum of relativistic Breit-Wigner amplitudes representing different vector meson resonances decaying to muon pairs, each with their own magnitude and phase. The measured phases of the [Formula: see text] and [Formula: see text] resonances are such that the interference with the short-distance component in dimuon mass regions far from their pole masses is small. In addition, constraints are placed on the Wilson coefficients, [Formula: see text] and [Formula: see text], and the branching fraction of the short-distance component is measured.
Collapse
|
46
|
Observation of the Annihilation Decay Mode B^{0}→K^{+}K^{-}. PHYSICAL REVIEW LETTERS 2017; 118:081801. [PMID: 28282211 DOI: 10.1103/physrevlett.118.081801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Indexed: 06/06/2023]
Abstract
A search for the B^{0}→K^{+}K^{-} decay is performed using pp-collision data collected by LHCb. The data set corresponds to integrated luminosities of 1.0 and 2.0 fb^{-1} at center-of-mass energies of 7 and 8 TeV, respectively. This decay is observed for the first time, with a significance of more than 5 standard deviations. The analysis also results in an improved measurement of the branching fraction for the B_{s}^{0}→π^{+}π^{-} decay. The measured branching fractions are B(B^{0}→K^{+}K^{-})=(7.80±1.27±0.81±0.21)×10^{-8} and B(B_{s}^{0}→π^{+}π^{-})=(6.91±0.54±0.63±0.19±0.40)×10^{-7}. The first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the B^{0}→K^{+}π^{-} branching fraction used as a normalization. For the B_{s}^{0} mode, the fourth accounts for the uncertainty on the ratio of the probabilities for b quarks to hadronize into B_{s}^{0} and B^{0} mesons.
Collapse
|
47
|
Observation of the Decay Ξ_{b}^{-}→pK^{-}K^{-}. PHYSICAL REVIEW LETTERS 2017; 118:071801. [PMID: 28256886 DOI: 10.1103/physrevlett.118.071801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Indexed: 06/06/2023]
Abstract
Decays of the Ξ_{b}^{-} and Ω_{b}^{-} baryons to the charmless final states ph^{-}h^{'-}, where h^{(')} denotes a kaon or pion, are searched for with the LHCb detector. The analysis is based on a sample of proton-proton collision data collected at center-of-mass energies sqrt[s]=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb^{-1}. The decay Ξ_{b}^{-}→pK^{-}K^{-} is observed with a significance of 8.7 standard deviations, and evidence at the level of 3.4 standard deviations is found for the Ξ_{b}^{-}→pK^{-}π^{-} decay. Results are reported, relative to the B^{-}→K^{+}K^{-}K^{-} normalization channel, for the products of branching fractions and b-hadron production fractions. The branching fractions of Ξ_{b}^{-}→pK^{-}π^{-} and Ξ_{b}^{-}→pπ^{-}π^{-} relative to Ξ_{b}^{-}→pK^{-}K^{-} decays are also measured.
Collapse
|
48
|
Observation of [Formula: see text] and [Formula: see text] decays. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:72. [PMID: 28331428 PMCID: PMC5341203 DOI: 10.1140/epjc/s10052-017-4610-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 01/07/2017] [Indexed: 06/06/2023]
Abstract
The decays [Formula: see text] and [Formula: see text] are observed for the first time using a data sample corresponding to an integrated luminosity of 3.0 fb[Formula: see text], collected by the LHCb experiment in proton-proton collisions at the centre-of-mass energies of 7 and 8[Formula: see text]. The branching fractions relative to that of [Formula: see text] are measured to be [Formula: see text]where the first uncertainties are statistical and the second are systematic.
Collapse
|
49
|
Measurement of the b-Quark Production Cross Section in 7 and 13 TeV pp Collisions. PHYSICAL REVIEW LETTERS 2017; 118:052002. [PMID: 28211722 DOI: 10.1103/physrevlett.118.052002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Indexed: 06/06/2023]
Abstract
Measurements of the cross section for producing b quarks in the reaction pp→bb[over ¯]X are reported in 7 and 13 TeV collisions at the LHC as a function of the pseudorapidity η in the range 2<η<5 covered by the acceptance of the LHCb experiment. The measurements are done using semileptonic decays of b-flavored hadrons decaying into a ground-state charmed hadron in association with a muon. The cross sections in the covered η range are 72.0±0.3±6.8 and 154.3±1.5±14.3 μb for 7 and 13 TeV. The ratio is 2.14±0.02±0.13, where the quoted uncertainties are statistical and systematic, respectively. The agreement with theoretical expectation is good at 7 TeV, but differs somewhat at 13 TeV. The measured ratio of cross sections is larger at lower η than the model prediction.
Collapse
|
50
|
Rate of Asparagine Deamidation in a Monoclonal Antibody Correlating with Hydrogen Exchange Rate at Adjacent Downstream Residues. Anal Chem 2017; 89:2361-2368. [DOI: 10.1021/acs.analchem.6b04158] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|