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The COMPASS Collaboration performed measurements of the Drell-Yan process in 2015 and 2018 using a 190 GeV/c π^{-} beam impinging on a transversely polarized ammonia target. Combining the data of both years, we present final results on the amplitudes of five azimuthal modulations, which correspond to transverse-spin-dependent azimuthal asymmetries (TSAs) in the dimuon production cross section. Three of them probe the nucleon leading-twist Sivers, transversity, and pretzelosity transverse-momentum dependent (TMD) parton distribution functions (PDFs). The other two are induced by subleading effects. These TSAs provide unique new inputs for the study of the nucleon TMD PDFs and their universality properties. In particular, the Sivers TSA observed in this measurement is consistent with the fundamental QCD prediction of a sign change of naive time-reversal-odd TMD PDFs when comparing the Drell-Yan process with deep inelastic scattering. Also, within the context of model predictions, the observed transversity TSA is consistent with the expectation of a sign change for the Boer-Mulders function.
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The COMPASS Collaboration experiment recently discovered a new isovector resonancelike signal with axial-vector quantum numbers, the a_{1}(1420), decaying to f_{0}(980)π. With a mass too close to and a width smaller than the axial-vector ground state a_{1}(1260), it was immediately interpreted as a new light exotic meson, similar to the X, Y, Z states in the hidden-charm sector. We show that a resonancelike signal fully matching the experimental data is produced by the decay of the a_{1}(1260) resonance into K^{*}(âKπ)K[over ¯] and subsequent rescattering through a triangle singularity into the coupled f_{0}(980)π channel. The amplitude for this process is calculated using a new approach based on dispersion relations. The triangle-singularity model is fitted to the partial-wave data of the COMPASS experiment. Despite having fewer parameters, this fit shows a slightly better quality than the one using a resonance hypothesis and thus eliminates the need for an additional resonance in order to describe the data. We thereby demonstrate for the first time in the light-meson sector that a resonancelike structure in the experimental data can be described by rescattering through a triangle singularity, providing evidence for a genuine three-body effect.
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The first measurement of transverse-spin-dependent azimuthal asymmetries in the pion-induced Drell-Yan (DY) process is reported. We use the CERN SPS 190 GeV/c π^{-} beam and a transversely polarized ammonia target. Three azimuthal asymmetries giving access to different transverse-momentum-dependent (TMD) parton distribution functions (PDFs) are extracted using dimuon events with invariant mass between 4.3 GeV/c^{2} and 8.5 GeV/c^{2}. Within the experimental uncertainties, the observed sign of the Sivers asymmetry is found to be consistent with the fundamental prediction of quantum chromodynamics (QCD) that the Sivers TMD PDFs extracted from DY have a sign opposite to the one extracted from semi-inclusive deep-inelastic scattering (SIDIS) data. We present two other asymmetries originating from the pion Boer-Mulders TMD PDFs convoluted with either the nucleon transversity or pretzelosity TMD PDFs. A recent COMPASS SIDIS measurement was obtained at a hard scale comparable to that of these DY results. This opens the way for possible tests of fundamental QCD universality predictions.
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BACKGROUND: Simultaneous bilateral retinal detachment (RD) is very rare and its incidence has not been very well characterised. MATERIAL AND METHODS: Retrospective review of RD cases treated at the Jules Gonin Eye Hospital between 1999 and 2010. RESULTS: Over the 11 year period, 10 patients (20 eyes) with simultaneous bilateral RD were identified (average incidence among RD= 0.9â%). Mean age: 46.4 ± 17.6 years, with a Mâ:âF Ratio of 6â:â4. Pseudophakia was present in 10 eyes and myopia ≥-5.0 dioptres in 11 eyes. Visual symptoms were unilateral in 7 patients, bilateral in 2 patients and absent in one patient. RD was macula-on in 15 eyes and macula-off in 5 eyes. Atrophic holes were present in 11 eyes, U-tears in 6 eyes and a combination in 3 eyes. Primary surgery consisted of buckle surgery (11 eyes), vitrectomy (6 eyes) and combines technique (3 eyes). The final anatomical success rate was 100â%. Mean follow-up time was 22.7 ± 4.95 months. CONCLUSION: The incidence of bilateral simultaneous RD appears to be very low and surgical success rates are excellent. Bilateral pre-operative dilated fundoscopy is mandatory, as the majority of patients have unilateral symptoms.
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Descolamento Retiniano/epidemiologia , Descolamento Retiniano/cirurgia , Recurvamento da Esclera/estatística & dados numéricos , Transtornos da Visão/epidemiologia , Transtornos da Visão/prevenção & controle , Vitrectomia/estatística & dados numéricos , Causalidade , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Descolamento Retiniano/diagnóstico , Estudos Retrospectivos , Fatores de Risco , Suíça/epidemiologia , Resultado do Tratamento , Transtornos da Visão/diagnóstico , Acuidade VisualRESUMO
The COMPASS Collaboration at CERN has measured diffractive dissociation of 190 GeV/c pions into the π(-)π(-)π(+) final state using a stationary hydrogen target. A partial-wave analysis (PWA) was performed in bins of 3π mass and four-momentum transfer using the isobar model and the so far largest PWA model consisting of 88 waves. A narrow peak is observed in the f0(980)π channel with spin, parity and C-parity quantum numbers J(PC)=1(++). We present a resonance-model study of a subset of the spin-density matrix selecting 3π states with J(PC)=2(++) and 4(++) decaying into ρ(770)π and with J(PC)=1(++) decaying into f0(980)π. We identify a new a1 meson with mass (1414(-13)(+15)) MeV/c2 and width (153(-23)(+8)) MeV/c2. Within the final states investigated in our analysis, we observe the new a1(1420) decaying only into f0(980)π, suggesting its exotic nature.
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Precise knowledge of the group velocity dispersion in gas-filled hollow-core photonic crystal fiber is essential for accurate modeling of ultrafast nonlinear dynamics. Here we study the validity of the capillary approximation commonly used to calculate the modal refractive index in kagomé-style photonic crystal fibers. For area-preserving core radius a(AP) and core wall thickness t, measurements and finite element simulations show that the approximation has an error greater than 15% for wavelengths longer than 0.56â(a(AP)t), independently of the gas-filling pressure. By introducing an empirical wavelength-dependent core radius, the range of validity of the capillary approximation is extended out to a wavelength of at least 0.98â(a(AP)t).
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STUDY DESIGN: Mixed methods study design. OBJECTIVES: The Work Rehabilitation Questionnaire-Self-Report Version (WORQ-SELF) is an assessment tool based on the International Classification of Functioning, Disability and Health (ICF) developed to evaluate functioning in different patient populations in vocational rehabilitation (VR) settings. The objective of this study is to establish the content validity of WORQ-SELF in a subgroup of spinal cord injury (SCI) patients in the early post-acute context. SETTING: Swiss Paraplegic Research and Swiss Paraplegic Centre, Nottwil, Switzerland. METHODS: Contents of WORQ-SELF were compared with semi-guided interviews with SCI patients in Switzerland, the Comprehensive ICF Core Set for SCI early post-acute, and outcome instruments used in VR and SCI. A frequency analysis was performed. RESULTS: WORQ-SELF represented 46 different ICF categories and of these 37 categories were confirmed by the patient interviews. The Comprehensive ICF Core Set for SCI confirmed 25 categories. Four instruments used in VR and SCI setting were identified. Contents of those instruments confirmed 14 categories of WORQ-SELF. Overall, 26 categories of the WORQ-SELF were confirmed by at least 2 of the 3 sources, 13 categories by 1 source and 7 were not confirmed by any of the sources. CONCLUSION: The WORQ-SELF proved to have content validity for utility in patients with SCI within the context of VR. WORQ-SELF can be used to assess the functioning and disability of patients in the return to work process.
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Avaliação da Deficiência , Traumatismos da Medula Espinal/reabilitação , Adolescente , Adulto , Feminino , Humanos , Classificação Internacional de Doenças , Masculino , Pessoa de Meia-Idade , Reabilitação Vocacional/métodos , Autorrelato , Inquéritos e Questionários , Suíça , Adulto JovemRESUMO
The COMPASS Collaboration at CERN has investigated the π- γ â π- π- π+ reaction at center-of-momentum energy below five pion masses, sqrt[s]<5m(π), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t'<0.001 GeV2/c2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3π-invariant mass m(3π)=sqrt[s] were extracted. The absolute cross section was determined in seven bins of sqrt[s] with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.
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We report the observation of a steepening in the cosmic ray energy spectrum of heavy primary particles at about 8×10(16) eV. This structure is also seen in the all-particle energy spectrum, but is less significant. Whereas the "knee" of the cosmic ray spectrum at 3-5×10(15) eV was assigned to light primary masses by the KASCADE experiment, the new structure found by the KASCADE-Grande experiment is caused by heavy primaries. The result is obtained by independent measurements of the charged particle and muon components of the secondary particles of extensive air showers in the primary energy range of 10(16) to 10(18) eV. The data are analyzed on a single-event basis taking into account also the correlation of the two observables.
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Two classes of rotating neutron stars-soft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars-are magnetars, whose X-ray emission is powered by a very strong magnetic field (B approximately 10(15) G). SGRs occasionally become 'active', producing many short X-ray bursts. Extremely rarely, an SGR emits a giant flare with a total energy about a thousand times higher than in a typical burst. Here we report that SGR 1806-20 emitted a giant flare on 27 December 2004. The total (isotropic) flare energy is 2 x 10(46) erg, which is about a hundred times higher than the other two previously observed giant flares. The energy release probably occurred during a catastrophic reconfiguration of the neutron star's magnetic field. If the event had occurred at a larger distance, but within 40 megaparsecs, it would have resembled a short, hard gamma-ray burst, suggesting that flares from extragalactic SGRs may form a subclass of such bursts.
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Degeneração Macular/diagnóstico , Degeneração Macular/etiologia , Descolamento Retiniano/cirurgia , Recurvamento da Esclera/efeitos adversos , Transtornos da Visão/etiologia , Transtornos da Visão/prevenção & controle , Idoso , Diagnóstico Diferencial , Humanos , Degeneração Macular/prevenção & controle , Masculino , Descolamento Retiniano/complicações , Resultado do Tratamento , Transtornos da Visão/diagnóstico , Acuidade VisualRESUMO
The COMPASS experiment at the CERN SPS has studied the diffractive dissociation of negative pions into the π- π- π+ final state using a 190 GeV/c pion beam hitting a lead target. A partial wave analysis has been performed on a sample of 420,000 events taken at values of the squared 4-momentum transfer t' between 0.1 and 1 GeV2/c2. The well-known resonances a1(1260), a2(1320), and π2(1670) are clearly observed. In addition, the data show a significant natural-parity exchange production of a resonance with spin-exotic quantum numbers J(PC)=1-+ at 1.66 GeV/c2 decaying to ρπ. The resonant nature of this wave is evident from the mass-dependent phase differences to the J(PC)=2-+ and 1++ waves. From a mass-dependent fit a resonance mass of (1660±10(-64)(+0)) MeV/c2 and a width of (269±21(-64)(+42)) MeV/c2 are deduced, with an intensity of (1.7±0.2)% of the total intensity.
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INTRODUCTION: Cytomegalovirus (CMV) infection is a relevant cause of morbidity and mortality in transplantation patients. Its major incidence is in the first year and viral replication is related to acute rejection, survival reduction, and graft vascular disease. OBJECTIVE: This study aims to evaluate retrospectively whether a high dose of calcineurin inhibitors correlates with CMV-positive polymerase chain reaction (PCR), need for treatment, and death in cardiac transplantation patients. METHODS: This is a case-control study including patients who underwent transplantation between 2014 and 2016. They were separated into two groups (positive or negative PCR) and evaluated for dosage serum levels of cyclosporine and tacrolimus. Patients were classified with adequate dose of immunosuppressant or high dose, and was analyzed that there was any association with those and positive CMV-PCR, need for treatment for CMV, and deaths. For statistical analysis, the Student t test was used for the quantitative variables and the Fisher's Exact Test for qualitative variables. To show CMV-free survival, the Kaplan-Meier curve was used. The level of significance was set at 5%. RESULTS: CMV-positive PCR in the sample was 72% for a total of 50 individuals. Positive PCR correlated with a high dose of calcineurin inhibitors in a statistically significant way (P = .002), as did a high dose of cyclosporine (P = .004); however, a high dose of tacrolimus had no such association (P = .17). When a high dose was assessed with a need for treatment, the chance of needing treatment increased more than eight times (P = .024; odds ratio = 8.25; 95% CI = 1.33 to 51.26), which was different from results found with high-dose tacrolimus (P = 1.0). However, no significant association was found in relation to deaths. CONCLUSIONS: Tacrolimus serum levels showed no association with CMV-PCR, which was different from serum cyclosporine, which showed association with CMV-PCR positivity, increasing the need for treatment approximately 8-fold, without association with death.
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Ciclosporina/efeitos adversos , Infecções por Citomegalovirus/induzido quimicamente , Transplante de Coração/efeitos adversos , Imunossupressores/efeitos adversos , Complicações Pós-Operatórias/induzido quimicamente , Tacrolimo/efeitos adversos , Adulto , Inibidores de Calcineurina/efeitos adversos , Estudos de Casos e Controles , Infecções por Citomegalovirus/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/virologia , Estudos Retrospectivos , Fatores de RiscoRESUMO
Prostatic tissue specimens derived from transurethral resections of patients with metastatic prostate cancer were analyzed for genetic alterations in the hormone-binding domain of the androgen receptor (AR) gene. Direct sequencing of the polymerase chain reaction-derived DNAs of 6 of 24 specimens revealed a codon 877 mutation (ACT-->GCT, Thr-->Ala) in the hormone-binding domain of the AR gene. This same AR mutation has been reported previously in a metastatic prostate cancer cell line, LNCaP, where this mutation confers upon the AR an altered ligand-binding specificity which is stimulated by estrogens, progestagens, and antiandrogens. It is possible that analogous to an activated/altered growth factor receptor oncogene, codon 877 mutant AR with altered ligand binding may provide a selective growth advantage in the genesis of a subset of advanced prostate cancer. Although estrogens are used infrequently, antiandrogens are used increasingly in hormonal therapy for patients with advanced prostate cancer. The stimulatory effect of these therapeutic agents on the codon 877 mutant AR further suggests that this frequently observed AR mutation may contribute to the treatment refractory disease.
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Códon/genética , Mutação Puntual/genética , Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Códon/química , DNA de Neoplasias/análise , Humanos , Masculino , Dados de Sequência Molecular , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Receptores Androgênicos/química , Análise de Sequência de DNA , Células Tumorais CultivadasRESUMO
Previously described primers for PCR amplification of variable immunoglobulin (Ig) genes were based on gene sequences. To include the large number of amino acid sequences of antibodies whose DNA has not been sequenced and to ensure a maximal fit to rearranged human Ig variable region genes, we have made a comprehensive comparison of both protein and nucleotide sequences. The resulting set of 15 primers was able to amplify a wide range of rearranged antibody variable region genes. Restriction sites included in the primers facilitate cloning of the PCR products into various expression vectors. Sequence analyses of PCR-amplified cDNA derived from a polyclonal B cell population showed that maximal enrichment is obtained for highly represented variable Ig gene subgroups. Rarely occurring V kappa 4 and V lambda 5 subgroups were not detected. Rearranged Ig variable region genes from each of 19 human B cell lines were also amplified. Comparisons to germline sequences allowed the allocation of rearranged genes to the original Ig genes. This primer set should be very useful for generating large repertoires of rearranged V genes and for amplifying genes of individual B cell clones.
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Rearranjo Gênico do Linfócito B , Genes de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Sequência Consenso , Primers do DNA , Humanos , Dados de Sequência Molecular , Mapeamento por Restrição , Alinhamento de Sequência , Homologia de Sequência de AminoácidosRESUMO
We present a case report where improper patient use of patient-controlled analgesia (PCA) in the postoperative period resulted in a significant delay in diagnosis of a postoperative myocardial infarction. Despite its excellent safety record and documented efficacy in controlling pain, PCA does have its limitations and can present a danger to the patient if operator error, patient error, or mechanical errors occur. Although the latter is rarely of concern, the two former possibilities exist. Other reported complications of PCA are discussed. We recommended that physicians, when considering use of patient-controlled anesthesia, discuss the qualitative and quantitative aspects of pain associated with the particular type of surgery performed to avoid missed postoperative complications.
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Analgesia Controlada pelo Paciente/efeitos adversos , Cistectomia/efeitos adversos , Infarto do Miocárdio/diagnóstico , Dor Pós-Operatória/tratamento farmacológico , Prostatectomia/efeitos adversos , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Morfina/administração & dosagem , Infarto do Miocárdio/etiologia , Segunda Neoplasia Primária/cirurgia , Dor Pós-Operatória/etiologia , Neoplasias da Próstata/cirurgia , Neoplasias da Bexiga Urinária/cirurgiaRESUMO
OBJECTIVES: To study, in a prospective fashion, acute traumatic effects on the gastrointestinal tract of patients treated by extracorporeal shock wave lithotripsy (ESWL). METHODS: Stool samples from each of 54 patients were tested before and after ESWL for conversion to hemoccult positive. A minimum of one negative pre-ESWL stool guaiac test was required for inclusion into the study. A minimum of two stool guaiac tests were done after ESWL to verify negativity. Patients who converted to a positive hemoccult test after ESWL were then evaluated by colonoscopy for the source of bleeding. RESULTS: Fifty patients completed the study. A single patient (2.0%) converted to a positive post-ESWL hemoccult test and was evaluated with colonoscopy. This patient was found to have two benign adenomatous polyps in the sigmoid and descending colon after treatment for a left renal pelvis calculus. An additional patient with a slightly positive post-ESWL conversion refused further evaluation. The overall post-ESWL conversion rate to guaiac positive, therefore, was less than 4% (2 of 51 patients). CONCLUSIONS: There is no evidence of significant trauma or detectable bleeding in the normal gastrointestinal tract caused by ESWL as measured by postprocedure stool guaiac testing. Guaiac testing of the stool after ESWL may unmask pre-existing gastrointestinal disease. Therefore a positive guaiac test after ESWL warrants further evaluation. This study reaffirms that ESWL is a safe, minimally invasive technique for the treatment of urolithiasis, without significant adverse side effects on the gastrointestinal tract.
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Sistema Digestório/lesões , Fezes/química , Guaiaco/metabolismo , Indicadores e Reagentes/metabolismo , Litotripsia/efeitos adversos , Sistema Digestório/metabolismo , Guaiaco/análise , Humanos , Incidência , Indicadores e Reagentes/análise , Estudos Prospectivos , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/etiologiaRESUMO
BACKGROUND: Transcranial sonography (TCS) identifies hyperechogenic basal ganglia in extrapyramidal disorders such as Parkinson's disease or dystonia and reveals brain atrophy reflecting the stage of degeneration in Huntington's disease. Aim of the present study was to evaluate the diagnostic potential of TCS in spinocerebellar ataxia type 3 (SCA3), a neurodegenerative disease affecting the cerebellum, multiple pontine nuclei, substantia nigra, pallidum, putamen, caudate nucleus and long spinal tracts. METHODS: 15 patients with a molecular diagnosis of SCA3 and 15 age- and sex-matched healthy control individuals were examined with TCS. Echogenicity of the substantia nigra, caudate nucleus, pallidum, putamen, dentate nucleus and cerebellar white matter were determined quantitatively (substantia nigra by measuring the area of incresed echogenicity) or semiquantitatively (0 = none, 1 = mild, 2 = marked) on both sides and compared with the echotexture of defined brain structures. Additionally, the width of the lateral ventricles, the 3rd and 4th ventricle was measured in both groups. RESULTS: SCA3 patients exhibited hyperechogenicities of the cerebellar white matter (57%), substantia nigra (40%), the dentate nucleus (54%), putamen (40%) and pallidum (40%) significantly more frequently (p <0.05) than controls (20%, 13%, 9%, 0%, and 0% in the corresponding areas). In none of the healthy individuals a marked signal increase could be observed, whereas 53% of SCA3 subjects had at least one region with marked echogenicity. Cerebellar atrophy as demonstrated by an enlarged 4th ventricle was observed in all SCA3 patients whereas this structure could not be differentiated from surrounding parenchyma due to its small size in healthy individuals. 3rd and lateral ventricles were significantly larger in SCA patients as compared to controls (p < 0.05). CONCLUSIONS: TCS is a suitable and non-invasive bed-side method to detect basal ganglia hyperechogenic lesions and posterior fossa abnormalities in SCA3 patients. The pattern of echotexture alterations and brain atrophy most likely reflects distribution and morphology of the neurodegenerative process.
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Encéfalo/patologia , Doença de Machado-Joseph/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Adulto , Idoso , Atrofia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não ParamétricasRESUMO
We describe a 48-year-old woman with loin pain-hematuria syndrome. Her renal abnormalities included conspicuous microaneurysmal and glomeruloid (plexiform) angiomatous changes. The deposition of both properdin and the C5b-9 complex, as well as the usual C3, in arterioles argues for complement activation. To our knowledge, neither of these features has been previously described. We speculate about the cause of loin pain-hematuria syndrome and note the uncommonness of this entity in the United States as opposed to Great Britain.