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PURPOSE: To study the relationship between the angiographic pattern of extrahepatic portal vein obstruction (EHPVO) and its etiology and clinical manifestations. METHODS: Clinical, etiological, and angiographic findings in 155 children with EHPVO were reviewed. Anatomy of extrahepatic portal venous system (EPVS) was categorized into five imaging patterns. Assessment of the severity of esophageal and gastric varices (EV and GV) was performed by upper gastrointestinal endoscopy. RESULTS: Based on multislice CT angiography, most commonly observed pattern of EHPVO was type I (48.4%) and type II (29%). According to anamnesis, 68 (43.8%) children had pathological conditions in neonatal period. Of these, 35 (22.6%) had an umbilical vein catheterization, 11 (7.1%) had a history of omphalitis, and 9 (5.8%) had prolonged jaundice. Thirteen (8.4%) patients had various septic conditions in neonatal period and it was more common associated with widespread thrombosis throughout the EPVS (type 5)-28% of observations. Significantly lower risk of bleeding from EV (p = 0.01) was noted in children with type IV pattern, whereas children with type III and V patterns had higher grades of EV. CONCLUSION: Angiographic pattern of portomesenteric occlusion may provide a clue to its etiology, and clinical manifestation, especially in children with widespread thrombosis throughout the EPVS.
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Várices Esofágicas y Gástricas , Hipertensión Portal , Enfermedades Vasculares , Recién Nacido , Niño , Humanos , Vena Porta/diagnóstico por imagen , Vena Porta/patología , Relevancia Clínica , Hemorragia Gastrointestinal/diagnóstico por imagen , Hemorragia Gastrointestinal/etiología , Hipertensión Portal/complicaciones , Hipertensión Portal/diagnóstico por imagen , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/complicacionesRESUMEN
OBJECTIVE: To evaluate postoperative outcomes in patients with chest wall metastases. MATERIAL AND METHODS: We analyzed 40 patients who underwent surgery for chest wall metastatic lesions. Fourteen (35%) patients had sternal lesion, 26 (65%) ones - rib metastases. We used implants for chest wall defect closure in 15 (37.5%) patients. Chest wall repair with autologous tissues was performed in 19 (47.5%) patients. RESULTS: Median survival was 17 months. Most patients (n=30, 75%) showed improvement in the quality of life according to Karnofsky and EGOG scale after surgery. Continued tumor growth occurred in 4 (10%) patients within 8-16 months after surgery. There were 2 patients who suffered from tumor recurrence accompanied by other metastatic foci (progression). Complications were diagnosed in 5 (12.5%) patients. Tactical errors were identified in 4 (10%) patients and they were associated with progression of cancer in the form of new metastatic foci within 6 months after surgery. CONCLUSION: Active surgical approach for bone metastases in patients with favorable cancer-related prognosis can improve quality of life and survival at least in case of solitary lesions. New program for treatment strategy selection based on prognosis of life expectancy and algorithms of surgical treatment will reduce the risk of erroneous management and increase its effectiveness.
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Neoplasias Óseas , Pared Torácica , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/patología , Neoplasias Óseas/cirugía , Humanos , Recurrencia Local de Neoplasia/cirugía , Pronóstico , Calidad de Vida , Pared Torácica/patología , Pared Torácica/cirugíaRESUMEN
OBJECTIVE: To improve treatment outcomes in patients with anorectal malformations via research of morphological criteria and differentiated approach to surgical correction. MATERIAL AND METHODS: There were 37 children with various types of anorectal malformations for the period 2000-2019. We analyzed morphological features of atretic rectum wall, fistula, anastomosis with adjacent organs and skin of the perineum. RESULTS: Morphological research of anorectal malformations made it possible to differentiate treatment strategy and explain the causes of unsatisfactory results after perineal and abdominal-perineal proctoplasty. Incidence and severity of complications, as well as early disability were reduced that significantly improved postoperative quality of life. CONCLUSION: According to the morphological criteria, deeper mobilization of atretic rectum within at least 2.5-3 cm of the rectal «cone¼ with intact muscular wall is necessary. This approach was valuable to ensure adequate closure function of the rectum, prevent anal incontinence and restore normal appearance of the perineum. These achievements contributed to decrease in the incidence of admissions, redo surgeries and improvement of social adaptation in children.
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Malformaciones Anorrectales , Incontinencia Fecal , Procedimientos de Cirugía Plástica , Canal Anal/anomalías , Canal Anal/cirugía , Malformaciones Anorrectales/patología , Malformaciones Anorrectales/cirugía , Niño , Incontinencia Fecal/etiología , Incontinencia Fecal/prevención & control , Incontinencia Fecal/cirugía , Humanos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Calidad de Vida , Procedimientos de Cirugía Plástica/efectos adversos , Procedimientos de Cirugía Plástica/métodos , Recto/anomalías , Recto/cirugíaRESUMEN
Results of ELISA investigation of the pretreatment sPD-1 and sPD-L1 content in blood serum of 133 bone neoplasms patients aged 6-70 years and 57 practically healthy control persons aged 12-70 years are described. In 14 patients the neoplasms were of a benign character, in 16 - borderline giant-cell bone tumor was diagnosed, and in 103 - malignant bone lesions including 39 osteosarcomas and 42 chondrosarcomas were revealed. The sPD-1 receptor concentrations in blood serum did not differ between control healthy persons and primary bone tumor patients, while serum sPD-L1 level in bone tumor patients was statistically significantly increased (p<0.0000001). By means of ROC curve construction a cut-off sPD-L1 level of 16.5 pg/ml was found that imposed 75,9% sensitivity and 75,4% specificity in relation to healthy control. However, the frequency of sPD-L1 levels exceeding 16.5 pg/ml was approximately similar in benign, borderline and malignant bone tumor patients. Analysis of the pattern of sPD-1 and sPD-L1 circulation in the peripheral blood of patients with the most prevalent malignant bone tumors - osteosarcoma and chondrosarcoma - demonstrated that in both sarcoma types sPD-L1 level was significantly higher than in control, but in patients with chondrogenic tumors the soluble ligand sPD-L1 dominates in the circulation, while in those with osteogenic tumors - sPD-1 receptor prevails. In particular, sPD-1 level is statistically significantly higher in patients with typical osteosarcoma than in those with typical chondrosarcoma (p=0.002437), and sPD-L1/sPD-1 concentration ratio in chondrosarcoma is highly significantly more than 2-fold higher than in osteosarcoma (0.81 and 0.35 respectively; p=0.000284). The sensitivity of sPD-L1 ≥16.5 pg/ml test in typical osteosarcoma patients' group comprised only 70.2%, and in those with typical chondrosarcoma - 84.6%. Serum sPD-1 and sPD-L1 concentrations in osteosarcoma and chondrosarcoma patients were not associated with the indices of tumor advancement, its histological grade, localization in the osseous system, and type of affected bone. Thus, it can be concluded that the ratio between circulating soluble forms of the receptor and the ligand of PD-1/PD-L signaling pathway differs between patients with chondrogenic and those with osteogenic tumors, sPD-L1 being diagnostically valuable mostly for chondrogenic bone neoplasms.
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Antígeno B7-H1/sangre , Neoplasias Óseas/sangre , Condrosarcoma/sangre , Osteosarcoma/sangre , Receptor de Muerte Celular Programada 1/sangre , Adolescente , Adulto , Anciano , Antígeno B7-H1/genética , Estudios de Casos y Controles , Niño , Humanos , Ligandos , Persona de Mediana Edad , Receptor de Muerte Celular Programada 1/genética , Adulto JovenRESUMEN
The levels of sPD-1 and sPD-L1 were analyzed in blood serum of 132 patients (age 14-70 years) with primary bone tumors: osteosarcoma (N=39), chondrosarcoma (N=42), Ewing sarcoma (N=9), chordoma (N=12), giant-cell bone tumor (GCBT) (N=16), benign neoplasms (N=14) and in and practically healthy subjects (age 19-58 years; N=27). sPD-L1 levels in all studied bone neoplasms were significantly higher than in the control. Serum sPD-1 level in GCBT patients was significantly higher than in the control, benign neoplasms, chondrosarcoma, and chordoma patients, but did not differ from osteosarcoma group. sPD-1 concentration in Ewing sarcoma was significantly higher than in chordoma and chondrosarcoma, but did not differ from the control. sPD-1 level in chondrosarcoma patients was also lower than in osteosarcoma, Ewing sarcoma, and in the control. Both sPD-1 and sPD-L1 concentrations were not significantly associated with the type of affected bone, process localization, disease stage, tumor histological grade, patients' age and sex. These results suggest the possibility of using these biological markers for preliminary assessment of the character of the process in the bone.
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Antígeno B7-H1/genética , Neoplasias Óseas/genética , Carcinoma de Células Gigantes/genética , Condrosarcoma/genética , Cordoma/genética , Osteosarcoma/genética , Receptor de Muerte Celular Programada 1/genética , Sarcoma de Ewing/genética , Adolescente , Adulto , Anciano , Antígeno B7-H1/sangre , Neoplasias Óseas/sangre , Neoplasias Óseas/inmunología , Neoplasias Óseas/patología , Carcinoma de Células Gigantes/sangre , Carcinoma de Células Gigantes/inmunología , Carcinoma de Células Gigantes/patología , Estudios de Casos y Controles , Condrosarcoma/sangre , Condrosarcoma/inmunología , Condrosarcoma/patología , Cordoma/sangre , Cordoma/inmunología , Cordoma/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasias/sangre , Neoplasias/genética , Neoplasias/inmunología , Neoplasias/patología , Osteosarcoma/sangre , Osteosarcoma/inmunología , Osteosarcoma/patología , Receptor de Muerte Celular Programada 1/sangre , Sarcoma de Ewing/sangre , Sarcoma de Ewing/inmunología , Sarcoma de Ewing/patologíaRESUMEN
OBJECTIVE: To perform a meta-analysis of studies examining the effectiveness of the local application of vancomycin powder for the prophylaxis of surgical site infections (SSIs) in spine surgery. MATERIAL AND METHODS: Retrospective cohort studies and prospective randomized clinical trials were searched for in the Pubmed, EMBASE, Cochrane Library and eLibrary databases published from 2008 to December 2018. For the resulting variables, the odds ratio and 95% confidence interval were calculated using random and fixed effects models. Estimation of the degree of heterogeneity is estimated using the coefficient I2. Statistically significant differences were considered differences p<0.05. RESULTS: The meta-analysis included 28 clinical studies that included the results of the local application of vancomycin powder in 17,469 patients after performing various spinal surgical interventions. Two publications had a prospective, randomized, controlled study design. Topical application of vancomycin powder reduces the incidence of SSIs after spine surgery (p<0.0001). The use of vancomycin powder reduces the incidence of SSIs in patients operated on with stabilizing implants (p=0.004). On the other hand, the topical application of vancomycin powder did not affect the prevalence of SSIs in respondents who were operated on without the use of stabilizing implants (p=0.12) or due to deformities of the spine (p=0.06). CONCLUSION: Topical application of vancomycin powder is highly effective in preventing the development of SSIs in patients after spinal surgical interventions.
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Antibacterianos/administración & dosificación , Columna Vertebral/cirugía , Infección de la Herida Quirúrgica/prevención & control , Vancomicina/administración & dosificación , Administración Tópica , Profilaxis Antibiótica , Humanos , Polvos/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto , Enfermedades de la Columna Vertebral/cirugía , Infección de la Herida Quirúrgica/etiologíaRESUMEN
PURPOSE: The aim of the study was to test the feasibility of spleen stiffness measurement (SSM) by two-dimensional shear wave elastography (2D-SWE) and compare data on its diagnostic use with upper gastrointestinal endoscopy in children with extrahepatic portal hypertension (EHPH) before and after surgery. METHODS: A total of 44 children were included in this study [34 children with EHPH (main group)] and 10 controls (7.57 ± 1.22 years), who underwent ultrasonography including SSM by 2D-SWE. Patients in the main group also underwent upper gastrointestinal endoscopy (UGE) and CT angiography. The main group was divided into three subgroups: Group A: patients with EHPH without large spontaneous portosystemic shunts (n = 15); Group B: patients with EHPH with large spontaneous portosystemic shunts (n = 9); Group C: patients with EHPVO and after surgical portosystemic shunts (n = 10). RESULTS: According to UGE, children in group A had significantly higher grades of esophageal varices (EV) (2.3 ± 0.14; p < 0.001) compared to those in groups B and C. After surgical shunting procedures (in group C), the grade of EV declined to 0.37 ± 0.14. There was significant difference (p < 0.001) in the mean SS of children in group A (70 ± 4.64 kPa) compared to those in group B (37.04 ± 4.62 kPa) and group C (26.3 ± 2.9 kPa). After surgery, SS decreased but remained elevated compared with controls (26.3 ± 2.9 vs 17.85 ± 1.3 kPa; p = 0.016). The SS showed a small but significant correlation with grades of EV (r = 0.56, p = 0.002). CONCLUSIONS: The SS measured by 2D-SWE is feasible in children with EHPH and the results reflect the presence or degree of EV, thus elastography of spleen is useful in monitoring portal hypertension before and after shunt surgeries.
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Diagnóstico por Imagen de Elasticidad/métodos , Hipertensión Portal/diagnóstico , Monitoreo Fisiológico/métodos , Vena Porta/diagnóstico por imagen , Bazo/diagnóstico por imagen , Enfermedades Vasculares/diagnóstico , Adolescente , Niño , Preescolar , Angiografía por Tomografía Computarizada , Constricción Patológica , Elasticidad , Endoscopía del Sistema Digestivo , Femenino , Humanos , Hipertensión Portal/fisiopatología , Hipertensión Portal/cirugía , Masculino , Vena Porta/cirugía , Derivación Portosistémica Quirúrgica , Bazo/fisiopatología , Enfermedades Vasculares/cirugíaRESUMEN
[This corrects the article DOI: 10.1140/epjc/s10052-017-4819-4.].
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AIM: The study aim was to perform a meta-analysis based on the results of randomized clinical trials comparing long-term outcomes of total intervertebral disc arthroplasty (TA) and anterior cervical spinal fusion (ACSF) in the surgical treatment of cervical degenerative disc disease. MATERIAL AND METHODS: We searched Pubmed, EMBASE, ELibrary, and Cochrane Library databases for randomized clinical trials reported between 2008 and August 2018. The relative risk and 95% confidence interval were calculated for dichotomous variables; for continuous variables, we used the standardized mean difference and their 95% CI with application of a random effects model. RESULTS: The metaanalysis involved 9 randomized controlled clinical trials including the long-term outcomes of surgical treatment in 2,439 patients. A pooled analysis of the data showed that regression of neurological symptoms (p<0.00001), improvement in the quality of life of patients (Neck Disability Index), and lower pain severity (visual analogue scale for upper extremities) were significantly more often observed (p=0.02) in the group of TA patients. In addition, the TA technique was characterized by a statistically significantly lower rate of re-surgery (p<0.0005) and degeneration of the superjacent segment (p<0.0001), with the rate of adverse events being slightly increased (p=0.04). CONCLUSION: Compared to anterior cervical spinal fusion, TA of cervical intervertebral discs is characterized by significantly better clinical efficacy in patients with cervical degenerative disc disease in the long-term postoperative follow-up.
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Artroplastia , Degeneración del Disco Intervertebral , Fusión Vertebral , Reeemplazo Total de Disco , Artroplastia/métodos , Vértebras Cervicales , Discectomía , Humanos , Disco Intervertebral/cirugía , Degeneración del Disco Intervertebral/cirugía , Calidad de Vida , Resultado del TratamientoRESUMEN
A search for new heavy particles that decay into top-quark pairs is performed using data collected from proton-proton collisions at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The integrated luminosity of the data sample is 36.1 fb - 1 . Events consistent with top-quark pair production are selected by requiring a single isolated charged lepton, missing transverse momentum and jet activity compatible with a hadronic top-quark decay. Jets identified as likely to contain b-hadrons are required to reduce the background from other Standard Model processes. The invariant mass spectrum of the candidate top-quark pairs is examined for local excesses above the background expectation. No significant deviations from the Standard Model predictions are found. Exclusion limits are set on the production cross-section times branching ratio for hypothetical Z ' bosons, Kaluza-Kein gluons and Kaluza-Klein gravitons that decay into top-quark pairs.
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Jet substructure observables have significantly extended the search program for physics beyond the standard model at the Large Hadron Collider. The state-of-the-art tools have been motivated by theoretical calculations, but there has never been a direct comparison between data and calculations of jet substructure observables that are accurate beyond leading-logarithm approximation. Such observables are significant not only for probing the collinear regime of QCD that is largely unexplored at a hadron collider, but also for improving the understanding of jet substructure properties that are used in many studies at the Large Hadron Collider. This Letter documents a measurement of the first jet substructure quantity at a hadron collider to be calculated at next-to-next-to-leading-logarithm accuracy. The normalized, differential cross section is measured as a function of log_{10}ρ^{2}, where ρ is the ratio of the soft-drop mass to the ungroomed jet transverse momentum. This quantity is measured in dijet events from 32.9 fb^{-1} of sqrt[s]=13 TeV proton-proton collisions recorded by the ATLAS detector. The data are unfolded to correct for detector effects and compared to precise QCD calculations and leading-logarithm particle-level Monte Carlo simulations.
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A search for new phenomena in final states containing an e+e- or µ+µ- pair, jets, and large missing transverse momentum is presented. This analysis makes use of proton-proton collision data with an integrated luminosity of 36.1fb-1 , collected during 2015 and 2016 at a centre-of-mass energy s=13TeV with the ATLAS detector at the Large Hadron Collider. The search targets the pair production of supersymmetric coloured particles (squarks or gluinos) and their decays into final states containing an e+e- or µ+µ- pair and the lightest neutralino ( χ~10 ) via one of two next-to-lightest neutralino ( χ~20 ) decay mechanisms: χ~20âZχ~10 , where the Z boson decays leptonically leading to a peak in the dilepton invariant mass distribution around the Z boson mass; and χ~20ââ+â-χ~10 with no intermediate â+â- resonance, 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 using simplified models, and exclude gluinos and squarks with masses as large as 1.85 and 1.3 Te at 95% confidence level, respectively.
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Li-Fraumeni syndrome (LFS) is a clinically and genetically heterogeneous hereditary syndrome with predominantly oncological manifestations, which is associated with mutations in the TP53, MDM2, and CHEK2 genes. The most common variant is a TP53 mutation. OBJECTIVE: To analyze the literature and present a clinical case of a patient with Li-Fraumeni syndrome and multiple anaplastic oligodendrogliomas of the brain. CLINICAL CASE: A 42-year-old male patient presented with complaints of headaches, word finding difficulty, memory loss, right hemianopsia, and generalized convulsive attacks. For 10 years, he underwent multiple interventions and chemotherapy courses for colon adenocarcinoma and recurrent B-cell lymphoma. MRI revealed multiple space-occupying lesions of the cerebraln hemispheres, which were located in the left temporo-occipital and right frontal regions. RESULTS: The patient underwent resection of multiple space-occupying lesions of the left temporo-occipital and right frontal regions. The postoperative period proceeded without complications. The histological diagnosis was WHO grade III anaplastic oligodendroglioma. The patient and one of his sons were detected with a R248W missense mutation in the TP53 gene. The patient underwent six courses of temozolomide chemotherapy. At a follow-up examination 20 months after surgery and chemotherapy, the patient's condition was satisfactory; he returned to work. Control MRI of the brain revealed no signs of continued tumor growth. CONCLUSION: An analysis of the literature and the clinical case indicate the success of multiple surgical interventions and chemotherapy courses performed for a long time in the patient with Li-Fraumeni syndrome manifested by colon adenocarcinoma, recurrent B-cell lymphoma, and multiple anaplastic oligodendroglioma of the brain. The patient had a good quality of life and returned to professional activity.
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Genes p53/genética , Síndrome de Li-Fraumeni/diagnóstico por imagen , Oligodendroglioma/diagnóstico por imagen , Adulto , Humanos , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/cirugía , Imagen por Resonancia Magnética , Masculino , Mutación Missense , Oligodendroglioma/genética , Oligodendroglioma/cirugía , Resultado del TratamientoRESUMEN
A search for the narrow structure, X(5568), reported by the D0 Collaboration in the decay sequence XâB_{s}^{0}π^{±}, B_{s}^{0}âJ/ψÏ, is presented. The analysis is based on a data sample recorded with the ATLAS detector at the LHC corresponding to 4.9 fb^{-1} of pp collisions at 7 TeV and 19.5 fb^{-1} at 8 TeV. No significant signal was found. Upper limits on the number of signal events, with properties corresponding to those reported by D0, and on the X production rate relative to B_{s}^{0} mesons, ρ_{X}, were determined at 95% confidence level. The results are N(X)<382 and ρ_{X}<0.015 for B_{s}^{0} mesons with transverse momenta above 10 GeV, and N(X)<356 and ρ_{X}<0.016 for transverse momenta above 15 GeV. Limits are also set for potential B_{s}^{0}π^{±} resonances in the mass range 5550 to 5700 MeV.
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A direct search for the standard model Higgs boson decaying to a pair of charm quarks is presented. Associated production of the Higgs and Z bosons, in the decay mode ZHââ^{+}â^{-}cc[over ¯] is studied. A data set with an integrated luminosity of 36.1 fb^{-1} of pp collisions at sqrt[s]=13TeV recorded by the ATLAS experiment at the LHC is used. The Hâcc[over ¯] signature is identified using charm-tagging algorithms. The observed (expected) upper limit on σ(ppâZH)×B(Hâcc[over ¯]) is 2.7 (3.9_{-1.1}^{+2.1}) pb at the 95% confidence level for a Higgs boson mass of 125 GeV, while the standard model value is 26 fb.
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A search for high-mass resonances decaying to τν using proton-proton collisions at sqrt[s]=13 TeV produced by the Large Hadron Collider is presented. Only τ-lepton decays with hadrons in the final state are considered. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 36.1 fb^{-1}. No statistically significant excess above the standard model expectation is observed; model-independent upper limits are set on the visible τν production cross section. Heavy W^{'} bosons with masses less than 3.7 TeV in the sequential standard model and masses less than 2.2-3.8 TeV depending on the coupling in the nonuniversal G(221) model are excluded at the 95% credibility level.
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The inclusive and fiducial t t ¯ production cross-sections are measured in the lepton+jets channel using 20.2 fb - 1 of proton-proton collision data at a centre-of-mass energy of 8 TeV recorded with the ATLAS detector at the LHC. Major systematic uncertainties due to the modelling of the jet energy scale and b-tagging efficiency are constrained by separating selected events into three disjoint regions. In order to reduce systematic uncertainties in the most important background, the W +\,jets process is modelled using Z + jets events in a data-driven approach. The inclusive t t ¯ cross-section is measured with a precision of 5.7% to be σ inc ( t t ¯ ) = 248.3 ± 0.7 ( stat . ) ± 13.4 ( syst . ) ± 4.7 ( lumi . ) pb , assuming a top-quark mass of 172.5 GeV. The result is in agreement with the Standard Model prediction. The cross-section is also measured in a phase space close to that of the selected data. The fiducial cross-section is σ fid ( t t ¯ ) = 48.8 ± 0.1 ( stat . ) ± 2.0 ( syst . ) ± 0.9 ( lumi . ) pb with a precision of 4.5%.
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A search for massive coloured resonances which are pair-produced and decay into two jets is presented. The analysis uses 36.7 fb - 1 of s = 13 TeV pp collision data recorded by the ATLAS experiment at the LHC in 2015 and 2016. No significant deviation from the background prediction is observed. Results are interpreted in a SUSY simplified model where the lightest supersymmetric particle is the top squark, t ~ , which decays promptly into two quarks through R-parity-violating couplings. Top squarks with masses in the range 100 GeV < m t ~ < 410 GeV are excluded at 95% confidence level. If the decay is into a b-quark and a light quark, a dedicated selection requiring two b-tags is used to exclude masses in the ranges 100 GeV < m t ~ < 470 GeV and 480 GeV < m t ~ < 610 GeV . Additional limits are set on the pair-production of massive colour-octet resonances.
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The results of a search for new heavy W ' bosons decaying to an electron or muon and a neutrino using proton-proton collision data at a centre-of-mass energy of s = 13 TeV are presented. The dataset was collected in 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 36.1 fb - 1 . As no excess of events above the Standard Model prediction is observed, the results are used to set upper limits on the W ' boson cross-section times branching ratio to an electron or muon and a neutrino as a function of the W ' mass. Assuming a W ' boson with the same couplings as the Standard Model W boson, W ' masses below 5.1 TeV are excluded at the 95% confidence level.
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A search for heavy resonances decaying into a pair of Z bosons leading to â + â - â + â - and â + â - ν ν ¯ final states, where â stands for either an electron or a muon, is presented. The search uses proton-proton collision data at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 36.1 fb - 1 collected with the ATLAS detector during 2015 and 2016 at the Large Hadron Collider. Different mass ranges for the hypothetical resonances are considered, depending on the final state and model. The different ranges span between 200 and 2000 GeV . The results are interpreted as upper limits on the production cross section of a spin-0 or spin-2 resonance. The upper limits for the spin-0 resonance are translated to exclusion contours in the context of Type-I and Type-II two-Higgs-doublet models, while those for the spin-2 resonance are used to constrain the Randall-Sundrum model with an extra dimension giving rise to spin-2 graviton excitations.