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Identifying structural risk factors for overdose following incarceration: a concept mapping study. HEALTH & JUSTICE 2024; 12:11. [PMID: 38472497 DOI: 10.1186/s40352-024-00265-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 02/29/2024] [Indexed: 03/14/2024]
Abstract
BACKGROUND Currently, there are more than two million people in prisons or jails, with nearly two-thirds meeting the criteria for a substance use disorder. Following these patterns, overdose is the leading cause of death following release from prison and the third leading cause of death during periods of incarceration in jails. Traditional quantitative methods analyzing the factors associated with overdose following incarceration may fail to capture structural and environmental factors present in specific communities. People with lived experiences in the criminal legal system and with substance use disorder hold unique perspectives and must be involved in the research process. OBJECTIVE To identify perceived factors that impact overdose following release from incarceration among people with direct criminal legal involvement and experience with substance use. METHODS Within a community-engaged approach to research, we used concept mapping to center the perspectives of people with personal experience with the carceral system. The following prompt guided our study: "What do you think are some of the main things that make people who have been in jail or prison more and less likely to overdose?" Individuals participated in three rounds of focus groups, which included brainstorming, sorting and rating, and community interpretation. We used the Concept Systems Inc. platform groupwisdom for our analyses and constructed cluster maps. RESULTS Eight individuals (ages 33 to 53) from four states participated. The brainstorming process resulted in 83 unique factors that impact overdose. The concept mapping process resulted in five clusters: (1) Community-Based Prevention, (2) Drug Use and Incarceration, (3) Resources for Treatment for Substance Use, (4) Carceral Factors, and (5) Stigma and Structural Barriers. CONCLUSIONS Our study provides critical insight into community-identified factors associated with overdose following incarceration. These factors should be accounted for during resource planning and decision-making.
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Ocular radiation exposure is negligible in normal volume endourological practice. Ann R Coll Surg Engl 2024. [PMID: 38445592 DOI: 10.1308/rcsann.2024.0004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024] Open
Abstract
INTRODUCTION The annual dose limit for radiation exposure to the eye has been reduced recently; the eye is widely recognised as one of the most radiosensitive tissues in the body. There is minimal good quality research as to the radiation dose that the eye receives during endourological surgery and this study aimed to address this. METHODS A prospective study was performed over an 8-month period at a single large teaching hospital in the UK. Three index procedures were included: ureteric stent insertion, ureteroscopy (URS) and percutaneous nephrolithotomy (PCNL). Surgeons wore a dosimeter on the glabella with fluoroscopy time (FT) and dose area product (DAP) recorded for each case. RESULTS A total of 404 procedures were included (247 URSs, 150 ureteric stent insertions and 7 PCNLs). Dosimeters were worn by ten surgeons. Mean FTs (URS 20.56s; ureteric stent 18.96s; PCNL 360.67s) and mean DAP (URS 100.82cGy/m2, ureteric stent 119.82cGy/m2 and PCNL 1121.62cGy/m2) were identified with significant intersurgeon variability. No surgeon had a total dosimeter dose >0.00mSv. CONCLUSIONS The International Commission on Radiological Protection recently reduced the yearly eye dose limit from 150 to 20mSv. Cataractogenesis is no longer considered a typical deterministic effect, with a threshold level below which no effect occurs. Even in higher volume centres, these annual limits are unlikely to be reached. Lead glasses may be considered for surgeons and radiologists with the highest exposure but, for the majority, ocular radiation exposure is negligible.
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Hosing of a Long Relativistic Particle Bunch in Plasma. PHYSICAL REVIEW LETTERS 2024; 132:075001. [PMID: 38427892 DOI: 10.1103/physrevlett.132.075001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 01/16/2024] [Indexed: 03/03/2024]
Abstract
Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, self-modulation in the perpendicular plane, at frequencies close to the plasma electron frequency, and are reproducible. Development of hosing depends on misalignment direction, its growth on misalignment extent and on proton bunch charge. Results have the main characteristics of a theoretical model, are relevant to other plasma-based accelerators and represent the first characterization of hosing.
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Child abuse and neglect and mental health outcomes in adulthood by ethnicity: Findings from a 40-year longitudinal study in New Zealand/Aotearoa. CHILD ABUSE & NEGLECT 2023; 145:106444. [PMID: 37703676 DOI: 10.1016/j.chiabu.2023.106444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 08/23/2023] [Accepted: 08/30/2023] [Indexed: 09/15/2023]
Abstract
BACKGROUND Longitudinal studies consistently report adverse long-term outcomes of childhood maltreatment. Little is known about the impact of childhood maltreatment on mental health among a marginalized population (New Zealand Māori); therefore, we cannot assume the effects of maltreatment are the same across the population. OBJECTIVE Associations were examined between childhood sexual abuse (CSA), childhood physical punishment (CPP) and childhood neglect (CN) (<16 years) and mental health outcomes 18-40 years, by ethnicity (Māori/non-Māori). PARTICIPANTS AND SETTING Data from the Christchurch Health and Development Study, a study of a birth cohort of 1265 children born in Christchurch in 1977. By age 40, 17.8 % (n = 191) reported New Zealand Māori ethnic identity; 82.2 % (n = 883) were non-Māori. METHODS CSA, CPP (<16 years) were measured at 18, 21 years; CN was measured at 40 years. Major depression, anxiety disorder, suicidal ideation, alcohol abuse/dependence and cannabis abuse/dependence were measured at ages 21, 25, 30, 35 and 40 years. Childhood confounding variables controlled. Analyses were extended to include Māori ethnicity. RESULTS After statistical adjustment, experience of severe childhood maltreatment increased odds of mental health problems 1.8-2.6×, compared to no maltreatment; the effects of maltreatment were similar for males and females. For Māori, some higher rates of mental health problems were seen among those maltreated, no statistically significant associations were detected after Bonferroni correction (among severe maltreatment vs. no maltreatment). Limitations should be considered when interpreting results. CONCLUSIONS Exposure to childhood maltreatment has long-term effects into middle-age. Further research employing culturally-sensitive approaches may help clarify Māori childhood maltreatment outcomes.
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A comparison of reward processing during Becker-DeGroot-Marschak and Vickrey auctions: An ERP study. Psychophysiology 2023; 60:e14313. [PMID: 37076995 PMCID: PMC10909440 DOI: 10.1111/psyp.14313] [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: 11/25/2022] [Revised: 02/24/2023] [Accepted: 03/27/2023] [Indexed: 04/21/2023]
Abstract
Vickrey auctions (VA) and Becker-DeGroot-Marschak auctions (BDM) are strategically equivalent demand-revealing mechanisms, differentiated only by a human opponent in the VA, and a random-number-generator opponent in the BDM. Game parameters are such that players are incentivized to reveal their private subjective values (SV) and behavior should be identical in both tasks. However, this has been repeatedly shown not to be the case. In this study, the neural correlates of outcome feedback processing during VA and BDM were directly compared using electroencephalography. Twenty-eight healthy participants bid for household products which were then divided into high- and low-SV categories. The VA included a human opponent deception to induce a social environment, while in reality a random-number-generator was used in both tasks. A P3 component peaking at 336 ms over midline parietal sites showed more positive amplitudes for high bid values, and for win outcomes in the VA but not the BDM. Both auctions also elicited a Reward Positivity potential, maximal at 275 ms along the central midline electrodes, that was not modulated by auction task or SV. Further, an exploratory N170 potential in the right occipitotemporal electrodes and a vertex positive potential component were stronger in the VA relative to the BDM. Results point to an enhanced cortical response to bid outcomes during VA task in a potential component associated with emotional control, and to the occurrence of face-sensitive potentials in VA but not in BDM auction. These findings suggest modulation of bid outcome processing by the social-competitive aspect of auction tasks. Directly comparing two prominent auction paradigms affords the opportunity to isolate the impact of social environment on competitive, risky decision-making. Findings suggest that feedback processing as early as 176 ms is facilitated by the presence of a human competitor, and later processing is modulated by social context and subjective value.
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Complications of vasectomy: Results from a prospective audit of 94,000 procedures. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00724-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Controlled Growth of the Self-Modulation of a Relativistic Proton Bunch in Plasma. PHYSICAL REVIEW LETTERS 2022; 129:024802. [PMID: 35867433 DOI: 10.1103/physrevlett.129.024802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.
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284 Wunderlich Syndrome - Case Report of a Surgical Emergency Due to Spontaneous Non-Traumatic Retroperitoneal Haemorrhage. Br J Surg 2021. [DOI: 10.1093/bjs/znab259.280] [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]
Abstract
Abstract
A 42-year-old female with no other significant co-morbidities presented with complaints of sudden onset abdominal pain, she was in state of shock- her haemoglobin dropped drastically to 6.8g/dl from 11.8g/dl. She was resuscitated and was given blood transfusion.
CT Scan was suggestive of retroperitoneal haemorrhage due to rupture of Renal angiomyolipoma (RAML). Patient underwent selective embolization of renal artery the next day and was discharged after 3 days of post-operative stay.
Wunderlich Syndrome-is a rare condition in which spontaneous nontraumatic renal haemorrhage occurs into the subcapsular and perirenal spaces is most commonly caused due to spontaneous rupture of RAML.It is characterized by Lenk’s triad – Acute flank pain, flank mass, hypovolemic shock. Size of AML (>4 cm), prothrombotic states such as pregnancy are main causes of AML rupture. Patients are managed conservatively or with help of selective arterial embolization. Nephrectomy is last resort in a hemodynamically unstable patient or in cases of embolization failure.
When dealing with acute abdomen with haemodynamic instability in non-traumatic cases it is essential to consider possibility of Wunderlich Syndrome. Early diagnosis, availability of Interventional radiology is key to successful management and potentially avoiding a Nephrectomy.
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Using Data to Drive Improvement: Impact of Reporting Process Compliance Rates on Heart Failure Re-Hospitalizations and 30 Day Mortality. J Heart Lung Transplant 2021. [DOI: 10.1016/j.healun.2021.01.825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Associations of Prenatal Methylmercury Exposure, Maternal PUFA Status and Neurodevelopment. Ann Epidemiol 2020. [DOI: 10.1016/j.annepidem.2020.09.019] [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]
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Quali sono le ragioni delle Missed Care? Risultato di uno studio bilaterale. Ragioni delle Missed Care. IGIENE E SANITA PUBBLICA 2020; 76:355-369. [PMID: 33783434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
BACKGROUND Evidence of missed nursing care in clinical practice has been well documented; however, fewer studies highlighting why care is missed have been conducted and this prevents effective interventions aimed at minimizing the missed care. METHODS A secondary analysis of two cross-sectional study designs was performed to capture the direction and strength of 1,114 Italian and Australian nurses' perceptions about why care was missed in their hospitals. The MISSCARE survey was used to collect data and the specific section aimed at estimating the reasons for missed nursing care was used. Data were analysed using structural equation modelling. RESULTS Six significant variables emerged as predictors of why care is missed, and these were: workplace miscommunication; increased work intensity; inadequate physical and human resources for care work; nurses' age; and years of clinical experience. CONCLUSIONS Australian and Italian findings contribute to growing international studies as to why nursing care is missed and provides a framework for understanding precipitating factors, such as incomplete workplace communication, unpredictable workflows, staffing and material resources issues might contribute to why care is missed and must thus be addressed/improved.
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Feasibility and acceptability of a remotely-delivered behavioural health coaching intervention to limit gestational weight gain. Obes Sci Pract 2020; 6:484-493. [PMID: 33082990 PMCID: PMC7556432 DOI: 10.1002/osp4.438] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 05/27/2020] [Accepted: 05/30/2020] [Indexed: 11/07/2022] Open
Abstract
INTRODUCTION Gestational weight gain (GWG) and postpartum weight retention (PPWR) are significant, potentially modifiable, contributors to women's future weight and health trajectories. There is a need for feasible and patient-centered (i.e., convenient, remotely-delivered, technology-enhanced, and accessible through the prenatal care setting) behavioural interventions that limit GWG and PPWR. This study tests the feasibility and acceptability of a remotely-delivered behavioural health coaching intervention to limit gestational weight gain and postpartum weight retention. METHODS Pregnant women (11-16 weeks gestation) were recruited from two prenatal clinics and randomized to the active intervention or health education comparison group. Completion of the program was monitored and perceived helpfulness was rated (0-100). RESULTS Twenty-six women were randomized (n = 13 per arm; mean age = 31.6 years, SD = 3.6; mean BMI = 26.7 kg/m2, SD = 7.4). Participants completed a median of 18 coaching calls and 16/19 learning activities during pregnancy, and a median of 6 calls and 5/6 learning activities postpartum. They logged weights at least once/week for a median of 36/38 expected weeks and tracked daily calories and exercise for a median of 154/266 days and 72/266 days, respectively. Median (Q1, Q3) helpfulness ratings of the program during pregnancy were 80 (64, 91) and 62 (50, 81) postpartum; helpfulness ratings of coaching calls were 85 (58, 98). At 37 weeks gestation, 77% of participants achieved IOM weight gain recommendations compared to 54% in the comparison group. CONCLUSIONS This study provides evidence for the feasibility and acceptability of a remotely-delivered behavioural weight control intervention in pregnancy and postpartum.
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Shape Coexistence at Zero Spin in ^{64}Ni Driven by the Monopole Tensor Interaction. PHYSICAL REVIEW LETTERS 2020; 125:102502. [PMID: 32955302 DOI: 10.1103/physrevlett.125.102502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
The low-spin structure of the semimagic ^{64}Ni nucleus has been considerably expanded: combining four experiments, several 0^{+} and 2^{+} excited states were identified below 4.5 MeV, and their properties established. The Monte Carlo shell model accounts for the results and unveils an unexpectedly complex landscape of coexisting shapes: a prolate 0^{+} excitation is located at a surprisingly high energy (3463 keV), with a collective 2^{+} state 286 keV above it, the first such observation in Ni isotopes. The evolution in excitation energy of the prolate minimum across the neutron N=40 subshell gap highlights the impact of the monopole interaction and its variation in strength with N.
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0853 Fetal Heart Rate Variability Increases During Maternal Sleep Apnea Events. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.849] [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
Abstract
Introduction
While studies have established that SDB during pregnancy increases the risk of adverse maternal outcomes, fetal effects are less well studied. Evidence suggests that fetal heart rate decelerations, an indicator of fetal distress, may be elicited by SDB. We examined the relationship between maternal SDB events and fetal heart rate (FHR) and fetal heart rate variability (FHRV).
Methods
Obese (BMI≥30kg/m2) non-smoking women carrying singleton fetuses underwent overnight polysomnography (34-37 weeks gestational age), with simultaneous fetal heart rate monitoring. Standard methods were used to score sleep, SDB events (apneas/hypopneas) and to analyze fetal heart rate parameters. Using linear mixed effect models, we examined changes in mean FHR and FHR variability (expressed by FHR SD) between the 10-second period immediately before individual SDB events, during events to the end of the associated oxygen desaturation period, and the 10-second period immediately following the SDB event.
Results
Valid PSG and FHR data were obtained from 85 third trimester maternal-fetal dyads. Across all participants, there were 2779 maternal SDB events (apneas or hypopneas). Mean AHI for individual subjects was 9.04 (SD 13.75). 39 women had OSA (AHI≥5), which was mostly mild. Mean FHR did not change significantly during and after episodes of SDB episodes compared to pre-event FHR, and did not change afterwards compared to during events, in unadjusted or adjusted (sleep stage, apnea type, degree of desaturation, age) analyses. In unadjusted analyses, FHRV significantly increased during SDB episodes compared to pre-SDB FHRV. After SDB events, FHRV was significantly lower than during SDB events. In fully adjusted models, these findings remained highly significant. FHRV was not significantly different after SDB events compared to pre-SDB event FHRV in unadjusted or adjusted models.
Conclusion
We observed consistent changes in FHR variability during and after maternal SDB events. Mean FHRV significantly increased during maternal SDB episodes compared to baseline FHRV, and decreased after SDB episodes. In contrast, mean FHR did not change significantly before, during and after SDB episodes. These data demonstrate that the fetus reacts to maternal SDB events, and raise questions about persistent effects of maternal SDB on the developing fetus.
Support
NIH HD079411
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Examining partnerships within an international knowledge translation network focused on youth mental health promotion. Health Res Policy Syst 2020; 18:29. [PMID: 32131848 PMCID: PMC7057628 DOI: 10.1186/s12961-020-0535-x] [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: 09/03/2019] [Accepted: 02/05/2020] [Indexed: 11/25/2022] Open
Abstract
Background Systems transformation for health promotion, involving engagement from multiple disciplines and levels of influence, requires an investment in partnership development. Integrated youth service is a collaborative model that brings organisations together to provide holistic care for youth. Frayme is an international knowledge translation network designed to support the uptake and scaling of integrated youth service. Social network analysis (SNA) is the study of relationships among social units and is useful to better understand how partners collaborate within a network to achieve major objectives. The purpose of this paper is to apply SNA to the Frayme network in order to (1) examine the level and strength of partnerships, (2) identify the strategies being employed to promote the main objectives and (3) apply the findings to current research in youth mental health and system transformation. Methods The PARTNER tool includes a validated survey and analysis software designed to examine partner interconnections. This tool was used to perform the SNA and 51 of the 75 partners completed the survey (14 researchers, 2 advisory groups and 35 organisations). A network map was created and descriptive frequencies were calculated. Results The overall network scores for the Frayme network were 20.6% for density, 81.5% for centralisation and 71.7% for overall trust. The Frayme secretariat received a 3.84 out of a possible 4 for value. In addition, the youth and family advisories each received a value score of 4 and all Leadership Team organisations received a score of 2.97 or above. Conclusions The Frayme secretariat links many partners who would otherwise be disconnected and acts as a significant conduit for novel information. Frayme may have the opportunity to enhance value perceptions among broader network members by profiling individual organisations and the potential leveraging opportunities that might exist through their work. These findings increase understanding with respect to the mechanisms of network development and will be helpful to inform partnership development in the future. In addition, they contribute to the literature with respect to knowledge translation practice as well as the scaling of collaborative interventions within youth mental health.
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SAT-267 AN INTERESTING CASE OF TYPE B DIALYSER REACTION TO POLYSULFONE DIALYSER MEMBRANE. Kidney Int Rep 2020. [DOI: 10.1016/j.ekir.2020.02.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Re "Endoscopic retrieval of retracted flexor tendons: An atraumatic technique". J Plast Reconstr Aesthet Surg 2020; 73:983-1007. [PMID: 32037075 DOI: 10.1016/j.bjps.2019.12.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 12/13/2019] [Indexed: 10/25/2022]
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A point prevalence study to determine the inpatient rate of carbapenemase-producing organisms at a large London NHS Trust. J Hosp Infect 2020; 104:12-19. [DOI: 10.1016/j.jhin.2019.10.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 10/14/2019] [Indexed: 10/25/2022]
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Letter comments on: Additional advancement after elevation of a neurovascular advancement flap with interposition of an artificial nerve conduit. J Plast Reconstr Aesthet Surg 2019; 72:2064-2094. [PMID: 31607589 DOI: 10.1016/j.bjps.2019.08.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 08/18/2019] [Indexed: 10/25/2022]
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Evidence for Rigid Triaxial Deformation in ^{76}Ge from a Model-Independent Analysis. PHYSICAL REVIEW LETTERS 2019; 123:102501. [PMID: 31573317 DOI: 10.1103/physrevlett.123.102501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Indexed: 06/10/2023]
Abstract
An extensive, model-independent analysis of the nature of triaxial deformation in ^{76}Ge, a candidate for neutrinoless double-beta (0νββ) decay, was carried out following multistep Coulomb excitation. Shape parameters deduced on the basis of a rotational-invariant sum-rule analysis provided considerable insight into the underlying collectivity of the ground-state and γ bands. Both sequences were determined to be characterized by the same β and γ deformation parameter values. In addition, compelling evidence for low-spin, rigid triaxial deformation in ^{76}Ge was obtained for the first time from the analysis of the statistical fluctuations of the quadrupole asymmetry deduced from the measured E2 matrix elements. These newly determined shape parameters are important input and constraints for calculations aimed at providing, with suitable accuracy, the nuclear matrix elements relevant to 0νββ.
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Preequilibrium Asymmetries in the ^{239}Pu(n,f) Prompt Fission Neutron Spectrum. PHYSICAL REVIEW LETTERS 2019; 122:072503. [PMID: 30848631 DOI: 10.1103/physrevlett.122.072503] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/09/2019] [Indexed: 06/09/2023]
Abstract
The physical properties of neutrons emitted from neutron-induced fission are fundamental to our understanding of nuclear fission. However, while state-of-the-art fission models still incorporate isotropic fission neutron spectra, it is believed that the preequilibrium prefission component of these spectra is strongly anisotropic. The lack of experimental guidance on this feature has not motivated incorporation of anisotropic neutron spectra in fission models, though any significant anisotropy would impact descriptions of a fissioning system. In the present work, an excess of counts at high energies in the fission neutron spectrum of ^{239}Pu is clearly observed and identified as an excess of the preequilibrium prefission distribution above the postfission neutron spectrum. This excess is separated from the underlying postfission neutron spectrum, and its angular distribution is determined as a function in incident neutron energy and outgoing neutron detection angle. Comparison with neutron scattering models provides the first experimental evidence that the preequilibrium angular distribution is uncorrelated with the fission axis. The results presented here also impact the interpretation of several influential prompt fission neutron spectrum measurements.
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Erratum to: Measurement of the W boson polarisation in t t ¯ events from pp collisions at s = 8 TeV in the lepton + jets channel with ATLAS. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2019; 79:19. [PMID: 31187788 PMCID: PMC6390723 DOI: 10.1140/epjc/s10052-018-6520-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 06/09/2023]
Abstract
[This corrects the article DOI: 10.1140/epjc/s10052-017-4819-4.].
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Letter re "Anaesthesia for collagenase clostridium histolyticom injection in patients with Dupuytren's disease: A cohort analysis". J Plast Reconstr Aesthet Surg 2018; 72:513-527. [PMID: 30583871 DOI: 10.1016/j.bjps.2018.11.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 11/03/2018] [Indexed: 11/18/2022]
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Localizing the Shape Transition in Neutron-Deficient Selenium. PHYSICAL REVIEW LETTERS 2018; 121:082502. [PMID: 30192612 DOI: 10.1103/physrevlett.121.082502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 07/23/2018] [Indexed: 06/08/2023]
Abstract
Neutron-deficient selenium isotopes are thought to undergo a rapid shape change from a prolate deformation near the line of beta stability towards oblate deformation around the line of N=Z. The point at which this shape change occurs is unknown, with inconsistent predictions from available theoretical models. A common feature in the models is the delicate nature of the point of transition, with the introduction of even a modest spin to the system sufficient to change the ordering of the prolate and oblate configurations. We present a measurement of the quadrupole moment of the first-excited state in radioactive ^{72}Se-a potential point of transition-by safe Coulomb excitation. This is the first low-energy Coulomb excitation to be performed with a rare-isotope beam at the reaccelerated beam facility at the National Superconducting Cyclotron Laboratory. By demonstrating a negative spectroscopic quadrupole moment for the first-excited 2^{+} state, it is found that any low-spin shape change in neutron-deficient selenium does not occur until ^{70}Se.
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Management of laser fibre during ureterorenoscopy and laser lithotripsy. Ann R Coll Surg Engl 2018; 100:1. [PMID: 29909676 PMCID: PMC6204501 DOI: 10.1308/rcsann.2018.0091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024] Open
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2.5-O8‘They’re not the flavour of the month’: regional primary health care organisations and primary health care for migrants and people from refugee backgrounds in Australia. Eur J Public Health 2018. [DOI: 10.1093/eurpub/cky047.077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Measurement of the W-boson mass in pp collisions at s = 7 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:110. [PMID: 31265006 PMCID: PMC6560917 DOI: 10.1140/epjc/s10052-018-6354-3 10.1140/epjc/s10052-017-5475-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 12/18/2017] [Indexed: 06/10/2023]
Abstract
A measurement of the mass of the W boson is presented based on proton-proton collision data recorded in 2011 at a centre-of-mass energy of 7 TeV with the ATLAS detector at the LHC, and corresponding to 4.6 fb - 1 of integrated luminosity. The selected data sample consists of 7.8 × 10 6 candidates in the W → μ ν channel and 5.9 × 10 6 candidates in the W → e ν channel. The W-boson mass is obtained from template fits to the reconstructed distributions of the charged lepton transverse momentum and of the W boson transverse mass in the electron and muon decay channels, yielding m W = 80370 ± 7 ( stat. ) ± 11 ( exp. syst. ) ± 14 ( mod. syst. ) MeV = 80370 ± 19 MeV , where the first uncertainty is statistical, the second corresponds to the experimental systematic uncertainty, and the third to the physics-modelling systematic uncertainty. A measurement of the mass difference between the W + and W - bosons yields m W + - m W - = - 29 ± 28 MeV.
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Measurement of the W-boson mass in pp collisions at s = 7 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:110. [PMID: 31265006 PMCID: PMC6560917 DOI: 10.1140/epjc/s10052-017-5475-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 12/18/2017] [Indexed: 05/18/2023]
Abstract
A measurement of the mass of the W boson is presented based on proton-proton collision data recorded in 2011 at a centre-of-mass energy of 7 TeV with the ATLAS detector at the LHC, and corresponding to 4.6 fb - 1 of integrated luminosity. The selected data sample consists of 7.8 × 10 6 candidates in the W → μ ν channel and 5.9 × 10 6 candidates in the W → e ν channel. The W-boson mass is obtained from template fits to the reconstructed distributions of the charged lepton transverse momentum and of the W boson transverse mass in the electron and muon decay channels, yieldingm W = 80370 ± 7 ( stat. ) ± 11 ( exp. syst. ) ± 14 ( mod. syst. ) MeV = 80370 ± 19 MeV , where the first uncertainty is statistical, the second corresponds to the experimental systematic uncertainty, and the third to the physics-modelling systematic uncertainty. A measurement of the mass difference between the W + and W - bosons yieldsm W + - m W - = - 29 ± 28 MeV.
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Advances at TRIUMF-ISAC and decay of neutron-rich Cd studied with GRIFFIN. EPJ WEB OF CONFERENCES 2018. [DOI: 10.1051/epjconf/201819304011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The β-decay half lives of nuclei near the r-process path are critical information required for abundance calculations, especially those near neutron number N = 82. Specifically, the nuclei below doubly-magic 132Sn are key, and play an important role in the formation and shape of the second r-process abundance peak. The half lives in this region are challenging to measure due to the significant β-delayed neutron decay branches and the population of isomeric states with half lives comparable to the ground states. However, by measuring the time distribution of γ rays, these complications can be eliminated. This requires, however, a very effcient γ-ray spectrometer since the production of isotopes in this region is very limited. The new GRIFFIN array at TRIUMF-ISAC provides the high effciency required for these measurements. Recent improvements in the quality of the beams produced at TRIUMF, employing the IG-LIS device, are outlined, as well as the current status of the ARIEL facility. The GRIFFIN spectrometer and its use are briefly described. The experiment to measure the half lives of 128-130Cd is outlined and the results given, and some examples of the power of GRIFFIN to expand decay schemes, specifically for the decay of 128Cd to 128In, are given.
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Discovery of ^{72}Rb: A Nuclear Sandbank Beyond the Proton Drip Line. PHYSICAL REVIEW LETTERS 2017; 119:192503. [PMID: 29219499 DOI: 10.1103/physrevlett.119.192503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Indexed: 06/07/2023]
Abstract
In this Letter, the observation of two previously unknown isotopes is presented for the first time: ^{72}Rb with 14 observed events and ^{77}Zr with one observed event. From the nonobservation of the less proton-rich nucleus ^{73}Rb, we derive an upper limit for the ground-state half-life of 81 ns, consistent with the previous upper limit of 30 ns. For ^{72}Rb, we have measured a half-life of 103(22) ns. This observation of a relatively long-lived odd-odd nucleus, ^{72}Rb, with a less exotic odd-even neighbor, ^{73}Rb, being unbound shows the diffuseness of the proton drip line and the possibility of sandbanks to exist beyond it. The ^{72}Rb half-life is consistent with a 5^{+}→5/2^{-} proton decay with an energy of 800-900 keV, in agreement with the atomic mass evaluation proton-separation energy as well as results from the finite-range droplet model and shell model calculations using the GXPF1A interaction. However, we cannot explicitly exclude the possibility of a proton transition between 9^{+}(^{72}Rb)→9/2^{+}(^{71}Kr) isomeric states with a broken mirror symmetry. These results imply that ^{72}Kr is a strong waiting point in x-ray burst rp-process scenarios.
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Fiducial, total and differential cross-section measurements of t-channel single top-quark production in pp collisions at 8 TeV using data collected by the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:531. [PMID: 28943801 PMCID: PMC5589447 DOI: 10.1140/epjc/s10052-017-5061-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 07/12/2017] [Indexed: 06/07/2023]
Abstract
Detailed measurements of t-channel single top-quark production are presented. They use 20.2 fb[Formula: see text] of data collected by the ATLAS experiment in proton-proton collisions at a centre-of-mass energy of 8 TeV at the LHC. Total, fiducial and differential cross-sections are measured for both top-quark and top-antiquark production. The fiducial cross-section is measured with a precision of 5.8% (top quark) and 7.8% (top antiquark), respectively. The total cross-sections are measured to be [Formula: see text] for top-quark production and [Formula: see text] for top-antiquark production, in agreement with the Standard Model prediction. In addition, the ratio of top-quark to top-antiquark production cross-sections is determined to be [Formula: see text]. The differential cross-sections as a function of the transverse momentum and rapidity of both the top quark and the top antiquark are measured at both the parton and particle levels. The transverse momentum and rapidity differential cross-sections of the accompanying jet from the t-channel scattering are measured at particle level. All measurements are compared to various Monte Carlo predictions as well as to fixed-order QCD calculations where available.
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Resident consultant obstetrician presence on the labour ward versus other models of consultant cover: a systematic review of intrapartum outcomes. BJOG 2017; 124:1311-1320. [PMID: 28244641 PMCID: PMC5574016 DOI: 10.1111/1471-0528.14527] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2016] [Indexed: 11/28/2022]
Abstract
BACKGROUND Several key policy documents have advocated 24-hour consultant obstetrician presence on the labour ward as a means of improving the safety of birth. However, it is unclear what published evidence exists comparing the outcomes of intrapartum care with 24-hour consultant labour ward presence and other models of consultant cover. OBJECTIVES To collate and critically appraise evidence of the effect of continuous resident consultant obstetrician cover on the labour ward on outcomes of intrapartum care compared with other models of consultant cover. SEARCH STRATEGY Studies were included which quantitatively compared intrapartum outcomes for women and babies where continuous resident consultant obstetric cover was provided with other models of consultant cover. SELECTION CRITERIA Quantitative studies within healthcare systems with mixed obstetric-midwifery models of care. DATA COLLECTION AND ANALYSIS Two researchers independently screened titles and full-text publications, extracted data and assessed the quality of included studies. Meta-analysis was performed using REVIEW MANAGER 5.3. MAIN RESULTS About 1508 publications were screened resulting in two papers, three conference abstracts and one letter being included. All were single-site time-period comparison studies. The quality of studies overall was poor with significant risk of bias. The only significant finding in meta-analysis related to instrumental deliveries, which occurred more frequently when there was on-call consultant cover (unadjusted risk ratio 1.14; 95% CI 1.04-1.24). CONCLUSION No reliable evidence of the effects of 24-hour resident consultant presence on the labour ward on intrapartum outcomes was identified. TWEETABLE ABSTRACT More robust research is needed to assess intrapartum outcomes with resident consultant labour ward presence.
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Topological cell clustering in the ATLAS calorimeters and its performance in LHC Run 1. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:490. [PMID: 28943797 PMCID: PMC5586976 DOI: 10.1140/epjc/s10052-017-5004-5] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 06/21/2017] [Indexed: 05/07/2023]
Abstract
The reconstruction of the signal from hadrons and jets emerging from the proton-proton collisions at the Large Hadron Collider (LHC) and entering the ATLAS calorimeters is based on a three-dimensional topological clustering of individual calorimeter cell signals. The cluster formation follows cell signal-significance patterns generated by electromagnetic and hadronic showers. In this, the clustering algorithm implicitly performs a topological noise suppression by removing cells with insignificant signals which are not in close proximity to cells with significant signals. The resulting topological cell clusters have shape and location information, which is exploited to apply a local energy calibration and corrections depending on the nature of the cluster. Topological cell clustering is established as a well-performing calorimeter signal definition for jet and missing transverse momentum reconstruction in ATLAS.
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Measurements of electroweak [Formula: see text] production and constraints on anomalous gauge couplings with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:474. [PMID: 28943794 PMCID: PMC5586972 DOI: 10.1140/epjc/s10052-017-5007-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 06/21/2017] [Indexed: 06/07/2023]
Abstract
Measurements of the electroweak production of a W boson in association with two jets at high dijet invariant mass are performed using [Formula: see text] 7 and 8 [Formula: see text] proton-proton collision data produced by the Large Hadron Collider, corresponding respectively to 4.7 and 20.2 fb[Formula: see text] of integrated luminosity collected by the ATLAS detector. The measurements are sensitive to the production of a W boson via a triple-gauge-boson vertex and include both the fiducial and differential cross sections of the electroweak process.
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Jet reconstruction and performance using particle flow with the ATLAS Detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:466. [PMID: 28943792 PMCID: PMC5586971 DOI: 10.1140/epjc/s10052-017-5031-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/27/2017] [Indexed: 06/07/2023]
Abstract
This paper describes the implementation and performance of a particle flow algorithm applied to 20.2 fb[Formula: see text] of ATLAS data from 8 TeV proton-proton collisions in Run 1 of the LHC. The algorithm removes calorimeter energy deposits due to charged hadrons from consideration during jet reconstruction, instead using measurements of their momenta from the inner tracker. This improves the accuracy of the charged-hadron measurement, while retaining the calorimeter measurements of neutral-particle energies. The paper places emphasis on how this is achieved, while minimising double-counting of charged-hadron signals between the inner tracker and calorimeter. The performance of particle flow jets, formed from the ensemble of signals from the calorimeter and the inner tracker, is compared to that of jets reconstructed from calorimeter energy deposits alone, demonstrating improvements in resolution and pile-up stability.
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Measurement of jet fragmentation in Pb+Pb and pp collisions at sNN=2.76 TeV with the ATLAS detector at the LHC. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:379. [PMID: 30215625 PMCID: PMC6129395 DOI: 10.1140/epjc/s10052-017-4915-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 05/12/2017] [Indexed: 06/08/2023]
Abstract
The distributions of transverse momentum and longitudinal momentum fraction of charged particles in jets are measured in Pb+Pb and pp collisions with the ATLAS detector at the LHC. The distributions are measured as a function of jet transverse momentum and rapidity. The analysis utilises an integrated luminosity of 0.14 nb - 1 of Pb+Pb data and 4.0 pb - 1 of pp data collected in 2011 and 2013, respectively, at the same centre-of-mass energy of 2.76 TeV per colliding nucleon pair. The distributions measured in pp collisions are used as a reference for those measured in Pb+Pb collisions in order to evaluate the impact on the internal structure of jets from the jet energy loss of fast partons propagating through the hot, dense medium created in heavy-ion collisions. Modest but significant centrality-dependent modifications of fragmentation functions in Pb+Pb collisions with respect to those in pp collisions are seen. No significant dependence of modifications on jet p T and rapidity selections is observed except for the fragments with the highest transverse momenta for which some reduction of yields is observed for more forward jets.
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Measurements of the production cross section of a [Formula: see text] boson in association with jets in pp collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:361. [PMID: 29200941 PMCID: PMC5689544 DOI: 10.1140/epjc/s10052-017-4900-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 05/08/2017] [Indexed: 06/01/2023]
Abstract
Measurements of the production cross section of a [Formula: see text] boson in association with jets in proton-proton collisions at [Formula: see text] TeV are presented, using data corresponding to an integrated luminosity of 3.16 fb[Formula: see text] collected by the ATLAS experiment at the CERN Large Hadron Collider in 2015. Inclusive and differential cross sections are measured for events containing a [Formula: see text] boson decaying to electrons or muons and produced in association with up to seven jets with [Formula: see text] GeV and [Formula: see text]. Predictions from different Monte Carlo generators based on leading-order and next-to-leading-order matrix elements for up to two additional partons interfaced with parton shower and fixed-order predictions at next-to-leading order and next-to-next-to-leading order are compared with the measured cross sections. Good agreement within the uncertainties is observed for most of the modelled quantities, in particular with the generators which use next-to-leading-order matrix elements and the more recent next-to-next-to-leading-order fixed-order predictions.
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Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton-proton collisions at the LHC. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:332. [PMID: 28943786 PMCID: PMC5586242 DOI: 10.1140/epjc/s10052-017-4887-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 05/05/2017] [Indexed: 05/30/2023]
Abstract
This paper presents the method and performance of primary vertex reconstruction in proton-proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of [Formula: see text] TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy. The measurement of the position and size of the luminous region and its use as a constraint to improve the primary vertex resolution are discussed. A longitudinal vertex position resolution of about [Formula: see text] is achieved for events with high multiplicity of reconstructed tracks. The transverse position resolution is better than [Formula: see text] and is dominated by the precision on the size of the luminous region. An analytical model is proposed to describe the primary vertex reconstruction efficiency as a function of the number of interactions per bunch crossing and of the longitudinal size of the luminous region. Agreement between the data and the predictions of this model is better than 3% up to seventy interactions per bunch crossing.
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Performance of the ATLAS trigger system in 2015. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:317. [PMID: 28943784 PMCID: PMC5586243 DOI: 10.1140/epjc/s10052-017-4852-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 04/23/2017] [Indexed: 05/07/2023]
Abstract
During 2015 the ATLAS experiment recorded [Formula: see text] of proton-proton collision data at a centre-of-mass energy of [Formula: see text]. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHC and shows the performance of the trigger system and its components based on the 2015 proton-proton collision data.
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Measurements of top-quark pair differential cross-sections in the [Formula: see text] channel in pp collisions at [Formula: see text] TeV using the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:292. [PMID: 28579920 PMCID: PMC5435111 DOI: 10.1140/epjc/s10052-017-4821-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 04/12/2017] [Indexed: 06/07/2023]
Abstract
This article presents measurements of [Formula: see text] differential cross-sections in a fiducial phase-space region, using an integrated luminosity of 3.2 fb[Formula: see text] of proton-proton data at a centre-of-mass energy of [Formula: see text] TeV recorded by the ATLAS experiment at the LHC in 2015. Differential cross-sections are measured as a function of the transverse momentum and absolute rapidity of the top quark, and of the transverse momentum, absolute rapidity and invariant mass of the [Formula: see text] system. The [Formula: see text] events are selected by requiring one electron and one muon of opposite electric charge, and at least two jets, one of which must be tagged as containing a b-hadron. The measured differential cross-sections are compared to predictions of next-to-leading order generators matched to parton showers and the measurements are found to be consistent with all models within the experimental uncertainties with the exception of the Powheg-Box [Formula: see text] Herwig++ predictions, which differ significantly from the data in both the transverse momentum of the top quark and the mass of the [Formula: see text] system.
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Measurement of the W boson polarisation in [Formula: see text] events from pp collisions at [Formula: see text] = 8 TeV in the lepton + jets channel with ATLAS. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:264. [PMID: 28515670 PMCID: PMC5409031 DOI: 10.1140/epjc/s10052-017-4819-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 04/11/2017] [Indexed: 06/07/2023]
Abstract
This paper presents a measurement of the polarisation of W bosons from [Formula: see text] decays, reconstructed in events with one high-[Formula: see text] lepton and at least four jets. Data from pp collisions at the LHC were collected at [Formula: see text] = 8 TeV and correspond to an integrated luminosity of 20.2 fb[Formula: see text]. The angle [Formula: see text] between the b-quark from the top quark decay and a direct W boson decay product in the W boson rest frame is sensitive to the W boson polarisation. Two different W decay products are used as polarisation analysers: the charged lepton and the down-type quark for the leptonically and hadronically decaying W boson, respectively. The most precise measurement of the W boson polarisation via the distribution of [Formula: see text] is obtained using the leptonic analyser and events in which at least two of the jets are tagged as b-quark jets. The fitted fractions of longitudinal, left- and right-handed polarisation states are [Formula: see text], [Formula: see text] and [Formula: see text], and are the most precisely measured W boson polarisation fractions to date. Limits on anomalous couplings of the Wtb vertex are set.
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Performance of algorithms that reconstruct missing transverse momentum in [Formula: see text]= 8 TeV proton-proton collisions in the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:241. [PMID: 28515666 PMCID: PMC5409168 DOI: 10.1140/epjc/s10052-017-4780-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 03/21/2017] [Indexed: 05/23/2023]
Abstract
The reconstruction and calibration algorithms used to calculate missing transverse momentum ([Formula: see text] ) with the ATLAS detector exploit energy deposits in the calorimeter and tracks reconstructed in the inner detector as well as the muon spectrometer. Various strategies are used to suppress effects arising from additional proton-proton interactions, called pileup, concurrent with the hard-scatter processes. Tracking information is used to distinguish contributions from the pileup interactions using their vertex separation along the beam axis. The performance of the [Formula: see text] reconstruction algorithms, especially with respect to the amount of pileup, is evaluated using data collected in proton-proton collisions at a centre-of-mass energy of 8 [Formula: see text] during 2012, and results are shown for a data sample corresponding to an integrated luminosity of [Formula: see text]. The simulation and modelling of [Formula: see text] in events containing a Z boson decaying to two charged leptons (electrons or muons) or a W boson decaying to a charged lepton and a neutrino are compared to data. The acceptance for different event topologies, with and without high transverse momentum neutrinos, is shown for a range of threshold criteria for [Formula: see text] , and estimates of the systematic uncertainties in the [Formula: see text] measurements are presented.
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Measurement of jet activity produced in top-quark events with an electron, a muon and two b-tagged jets in the final state in pp collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:220. [PMID: 28515663 PMCID: PMC5408996 DOI: 10.1140/epjc/s10052-017-4766-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 03/20/2017] [Indexed: 06/07/2023]
Abstract
Measurements of jet activity in top-quark pair events produced in proton-proton collisions are presented, using 3.2 fb[Formula: see text] of pp collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS experiment at the Large Hadron Collider. Events are chosen by requiring an opposite-charge [Formula: see text] pair and two b-tagged jets in the final state. The normalised differential cross-sections of top-quark pair production are presented as functions of additional-jet multiplicity and transverse momentum, [Formula: see text]. The fraction of signal events that do not contain additional jet activity in a given rapidity region, the gap fraction, is measured as a function of the [Formula: see text] threshold for additional jets, and is also presented for different invariant mass regions of the [Formula: see text] system. All measurements are corrected for detector effects and presented as particle-level distributions compared to predictions with different theoretical approaches for QCD radiation. While the kinematics of the jets from top-quark decays are described well, the generators show differing levels of agreement with the measurements of observables that depend on the production of additional jets.
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Electron efficiency measurements with the ATLAS detector using 2012 LHC proton-proton collision data. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:195. [PMID: 28579919 PMCID: PMC5434979 DOI: 10.1140/epjc/s10052-017-4756-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 03/14/2017] [Indexed: 05/23/2023]
Abstract
This paper describes the algorithms for the reconstruction and identification of electrons in the central region of the ATLAS detector at the Large Hadron Collider (LHC). These algorithms were used for all ATLAS results with electrons in the final state that are based on the 2012 pp collision data produced by the LHC at [Formula: see text] = 8 [Formula: see text]. The efficiency of these algorithms, together with the charge misidentification rate, is measured in data and evaluated in simulated samples using electrons from [Formula: see text], [Formula: see text] and [Formula: see text] decays. For these efficiency measurements, the full recorded data set, corresponding to an integrated luminosity of 20.3 fb[Formula: see text], is used. Based on a new reconstruction algorithm used in 2012, the electron reconstruction efficiency is 97% for electrons with [Formula: see text] [Formula: see text] and 99% at [Formula: see text] [Formula: see text]. Combining this with the efficiency of additional selection criteria to reject electrons from background processes or misidentified hadrons, the efficiency to reconstruct and identify electrons at the ATLAS experiment varies from 65 to 95%, depending on the transverse momentum of the electron and background rejection.
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Search for new phenomena in events containing a same-flavour opposite-sign dilepton pair, jets, and large missing transverse momentum in [Formula: see text] [Formula: see text][Formula: see text] collisions with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:144. [PMID: 28690423 PMCID: PMC5479494 DOI: 10.1140/epjc/s10052-017-4700-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 02/16/2017] [Indexed: 05/23/2023]
Abstract
Two searches for new phenomena in final states containing a same-flavour opposite-sign lepton (electron or muon) pair, jets, and large missing transverse momentum are presented. These searches make use of proton-proton collision data, collected during 2015 and 2016 at a centre-of-mass energy [Formula: see text] [Formula: see text] by the ATLAS detector at the large hadron collider, which correspond to an integrated luminosity of [Formula: see text]. Both searches target the pair production of supersymmetric particles, squarks or gluinos, which decay to final states containing a same-flavour opposite-sign lepton pair via one of two mechanisms: a leptonically decaying Z boson in the final state, leading to a peak in the dilepton invariant-mass distribution around the Z boson mass; and decays of neutralinos (e.g. [Formula: see text]), yielding a kinematic endpoint in the dilepton invariant-mass spectrum. The data are found to be consistent with the Standard Model expectation. Results are interpreted in simplified models of gluino-pair (squark-pair) production, and provide sensitivity to gluinos (squarks) with masses as large as 1.70 [Formula: see text] (980 [Formula: see text]).
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Search for triboson [Formula: see text] production in pp collisions at [Formula: see text] [Formula: see text] with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:141. [PMID: 28331433 PMCID: PMC5341259 DOI: 10.1140/epjc/s10052-017-4692-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 02/10/2017] [Indexed: 06/06/2023]
Abstract
This paper reports a search for triboson [Formula: see text] production in two decay channels ([Formula: see text] and [Formula: see text] with [Formula: see text]) in proton-proton collision data corresponding to an integrated luminosity of 20.3 [Formula: see text] at a centre-of-mass energy of 8 [Formula: see text] with the ATLAS detector at the Large Hadron Collider. Events with exactly three charged leptons, or two leptons with the same electric charge in association with two jets, are selected. The total number of events observed in data is consistent with the Standard Model (SM) predictions. The observed 95% confidence level upper limit on the SM [Formula: see text] production cross section is found to be 730 fb with an expected limit of 560 fb in the absence of SM [Formula: see text] production. Limits are also set on WWWW anomalous quartic gauge couplings.
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Search for anomalous electroweak production of
WW/WZ
in association with a high-mass dijet system in
pp
collisions at
s=8 TeV
with the ATLAS detector. Int J Clin Exp Med 2017. [DOI: 10.1103/physrevd.95.032001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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49
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Measurement of the prompt J/[Formula: see text] pair production cross-section in pp collisions at [Formula: see text] TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:76. [PMID: 28331429 PMCID: PMC5341209 DOI: 10.1140/epjc/s10052-017-4644-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 01/24/2017] [Indexed: 06/06/2023]
Abstract
The production of two prompt [Formula: see text] mesons, each with transverse momenta [Formula: see text] GeV and rapidity [Formula: see text], is studied using a sample of proton-proton collisions at [Formula: see text] TeV, corresponding to an integrated luminosity of 11.4 fb[Formula: see text] collected in 2012 with the ATLAS detector at the LHC. The differential cross-section, assuming unpolarised [Formula: see text] production, is measured as a function of the transverse momentum of the lower-[Formula: see text] [Formula: see text] meson, di-[Formula: see text] [Formula: see text] and mass, the difference in rapidity between the two [Formula: see text] mesons, and the azimuthal angle between the two [Formula: see text] mesons. The fraction of prompt pair events due to double parton scattering is determined by studying kinematic correlations between the two [Formula: see text] mesons. The total and double parton scattering cross-sections are compared with predictions. The effective cross-section of double parton scattering is measured to be [Formula: see text] mb.
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50
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Search for lepton-flavour-violating decays of the Higgs and Z bosons with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2017; 77:70. [PMID: 28775664 PMCID: PMC5512745 DOI: 10.1140/epjc/s10052-017-4624-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 01/15/2017] [Indexed: 06/06/2023]
Abstract
Direct searches for lepton flavour violation in decays of the Higgs and Z bosons with the ATLAS detector at the LHC are presented. The following three decays are considered: [Formula: see text], [Formula: see text], and [Formula: see text]. The searches are based on the data sample of proton-proton collisions collected by the ATLAS detector corresponding to an integrated luminosity of 20.3 [Formula: see text] at a centre-of-mass energy of [Formula: see text] TeV. No significant excess is observed, and upper limits on the lepton-flavour-violating branching ratios are set at the 95[Formula: see text] confidence level: Br[Formula: see text], Br[Formula: see text], and Br[Formula: see text].
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