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1.
Phys Rev Lett ; 130(5): 051802, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800478

RESUMO

The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q^{2} (squared four-momentum transfer) and energy, in the range 1 GeV≤E_{ν}<6 GeV. Detailed comparisons are made to the predictions of the GENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the others consistently across all three cross sections measured, though some models have especially good or poor agreement in the single differential cross section vs Q^{2}.

2.
Phys Rev Lett ; 128(13): 132502, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426711

RESUMO

Differential cross sections for Compton scattering from the proton have been measured at scattering angles of 55°, 90°, and 125° in the laboratory frame using quasimonoenergetic linearly (circularly) polarized photon beams with a weighted mean energy value of 83.4 MeV (81.3 MeV). These measurements were performed at the High Intensity Gamma-Ray Source facility at the Triangle Universities Nuclear Laboratory. The results are compared to previous measurements and are interpreted in the chiral effective field theory framework to extract the electromagnetic dipole polarizabilities of the proton, which gives α_{E1}^{p}=13.8±1.2_{stat}±0.1_{BSR}±0.3_{theo},ß_{M1}^{p}=0.2∓1.2_{stat}±0.1_{BSR}∓0.3_{theo} in units of 10^{-4} fm^{3}.

3.
Phys Rev Lett ; 127(20): 201801, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34860065

RESUMO

This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of 12.51×10^{20} protons-on-target from the NuMI beam at Fermilab running in antineutrino mode. A total of 121 of neutral-current candidates are observed at the far detector, compared to a prediction of 122±11(stat.)±15(syst.) assuming mixing only between three active flavors. No evidence for ν[over ¯]_{µ}→ν[over ¯]_{s} oscillation is observed. Interpreting this result within a 3+1 model, constraints are placed on the mixing angles θ_{24}<25° and θ_{34}<32° at the 90% C.L. for 0.05 eV^{2}≤Δm_{41}^{2}≤0.5 eV^{2}, the range of mass splittings that produces no significant oscillations at the near detector. These are the first 3+1 confidence limits set using long-baseline accelerator antineutrinos.

4.
Hand Surg Rehabil ; 40(2): 167-170, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33309795

RESUMO

Prophylactic antibiotics (PA) have been shown to be ineffective in reducing the incidence of surgical site infection (SSI) in clean wounds associated with elective surgery of the hand. Routine administration of PA for internal fixation of hand fractures is a subject that has been scarcely studied. We hypothesized that PA do not reduce SSI incidence in fixation of closed hand fractures. We did a retrospective comparative study in patients who underwent open or closed reduction and internal fixation of a hand and carpus fracture. Patient demographics, past medical history, fracture characteristics and the type of internal fixation used were extracted from our electronic archives. Follow-up period lasted for 1 year, during which any form of clinically evident SSI, such as pus formation, wound dehiscence and positive bacterial culture was documented. A total of 107 patients met the inclusion criteria, 63 in the control group and 44 in the test group. The overall infection rate was 6.5%. All infections (3 in the control group and 4 in the test group) were pin-tract infections that resolved completely after pin extraction. Our study did not find significant differences between groups (P = 0.442). No specific fracture pattern was associated with increased total infection rate (p = 0.898). In this study, we found no support for routine administration of PA prior to internal fixation of closed fractures of the hand and carpus. PA should still be administered in selected patients, such as those with decreased immunity or open fractures. Further large-scale research is needed to establish proper guidelines, to reduce the adverse effects of antibiotic treatment.


Assuntos
Fraturas Fechadas , Fraturas Expostas , Antibacterianos/uso terapêutico , Fixação Interna de Fraturas , Fraturas Fechadas/cirurgia , Humanos , Estudos Retrospectivos
5.
Phys Rev Lett ; 125(13): 131802, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034464

RESUMO

We report the final measurement of the neutrino oscillation parameters Δm_{32}^{2} and sin^{2}θ_{23} using all data from the MINOS and MINOS+ experiments. These data were collected using a total exposure of 23.76×10^{20} protons on target producing ν_{µ} and ν[over ¯]_{µ} beams and 60.75 kt yr exposure to atmospheric neutrinos. The measurement of the disappearance of ν_{µ} and the appearance of ν_{e} events between the Near and Far detectors yields |Δm_{32}^{2}|=2.40_{-0.09}^{+0.08}(2.45_{-0.08}^{+0.07})×10^{-3} eV^{2} and sin^{2}θ_{23}=0.43_{-0.04}^{+0.20}(0.42_{-0.03}^{+0.07}) at 68% C.L. for normal (inverted) hierarchy.

6.
Phys Rev Lett ; 125(7): 071801, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32857527

RESUMO

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{µe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13 eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.

7.
Hand Surg Rehabil ; 39(4): 328-331, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32387689

RESUMO

The second case of high temperature molten metal, high-pressure injection injury of the hand is reported here. Like in the previous case, there was an innocent-looking entry point with deep thermal injury to the flexor tendons and the digital nerves that appeared a few days after the injury and lead to finger amputation. LEVEL OF EVIDENCE: 5.


Assuntos
Queimaduras/cirurgia , Traumatismos da Mão/cirurgia , Metais/efeitos adversos , Traumatismos Ocupacionais/cirurgia , Pressão , Adulto , Antibacterianos/uso terapêutico , Queimaduras/etiologia , Desbridamento , Gentamicinas/uso terapêutico , Traumatismos da Mão/etiologia , Temperatura Alta/efeitos adversos , Humanos , Masculino
8.
Hand Surg Rehabil ; 39(3): 214-217, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32070790

RESUMO

We sought to report on the use of wide-awake local anesthesia and no tourniquet (WALANT) for internal fixation of metacarpal fractures. We retrospectively examined 10 patients with metacarpal fractures that required either closed reduction and internal fixation (CRIF) or open reduction and internal fixation (ORIF). WALANT was administered 20minutes before the surgery outside the operating room. Once the area was numb, an open or closed reduction was made followed by internal fixation of the fracture using plating, intramedullary screws or Kirshner wires (K-wires). We used intraoperative X-ray to confirm anatomic reduction and correct internal fixation. After proper reduction and fixation, the active range of motion (AROM) was assessed while the patient was awake. Patients were discharged the next day after evaluating their neurovascular status and establishing pain control. Follow-up evaluations were carried out at 2, 6 and 12 weeks postoperatively. All individuals underwent uneventful operations. No significant pain or bleeding was recorded during the operation. Nine out of ten patients regained full AROM at the 12-week follow-up visit in the outpatient clinic. One patient still had slight reduction of range of motion (ROM) of the 5th metacarpophalangeal joint. No neurovascular damage or surgical site morbidity was recorded. CRIF and ORIF of simple metacarpal fractures can be executed successfully using WALANT with good functional results without increased morbidity compared to monitored anesthesia care.


Assuntos
Anestesia Local , Anestésicos Locais/administração & dosagem , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Ossos Metacarpais/cirurgia , Adulto , Redução Fechada , Epinefrina/administração & dosagem , Feminino , Humanos , Injeções , Lidocaína/administração & dosagem , Masculino , Ossos Metacarpais/lesões , Pessoa de Meia-Idade , Redução Aberta , Amplitude de Movimento Articular , Estudos Retrospectivos , Adulto Jovem
9.
Hand Surg Rehabil ; 38(5): 312-316, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31400497

RESUMO

High-pressure injection injuries to the fingers resulting from the introduction of a foreign substance, such as oil or paint, through a minor puncture wound are rare but can have serious clinical consequences. The objective of this article was to examine the long-term outcomes after surgical debridement of these injuries. We present a retrospective case series of 8 adults who had a high-pressure injection injury to their hand and underwent surgical debridement in our facility. Data were extracted from our outpatient registry. Assessment included a full physical examination, grip strength, range of motion, two-point discrimination and Quick Disability of the Arm, Shoulder, and Hand (QuickDASH) questionnaire. We followed 8 male patients for an average of 12.7 years. Their average age was 37 at time of injury and all had injured their right dominant hand. Seventy-five percent of the injuries were to the index finger. Seven out of the 8 patients returned to their pre-injury occupation, 4 out of 8 patients had reduced range of motion of the affected digit. Injury sequelae adversely affected activities of daily living (ADL) with an average QuickDASH score of 26. Grip strength in the injured hand was reduced by an average of 35% in 6 out of 8 patients compared with the uninjured hand. Sensation was also reduced in the affected digit in 7 out of 8 patients. All patients suffered from some level of neuropathic pain and/or cold intolerance. High pressure injection injury to the fingers is a serious event found amongst industrial laborers. In most patients, this injury will lead to long-term disability along with a negative impact on ADL. However, most patients eventually return to their pre-injury occupation. Extensive, single or repeat debridement of high-pressure injection injuries remains a valid treatment option with good long-term results.


Assuntos
Ar Comprimido/efeitos adversos , Desbridamento , Traumatismos dos Dedos/cirurgia , Corpos Estranhos/cirurgia , Traumatismos Ocupacionais/cirurgia , Ferimentos Penetrantes/cirurgia , Atividades Cotidianas , Adulto , Avaliação da Deficiência , Seguimentos , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Óleos , Pintura , Amplitude de Movimento Articular , Estudos Retrospectivos , Retorno ao Trabalho , Solventes
10.
Phys Rev Lett ; 122(9): 091803, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932529

RESUMO

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×10^{20} protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter sin^{2}θ_{24} for most values of the sterile neutrino mass splitting Δm_{41}^{2}>10^{-4} eV^{2}.

11.
Phys Rev Lett ; 118(23): 231801, 2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28644674

RESUMO

Results are reported from an improved measurement of ν_{µ}→ν_{e} transitions by the NOvA experiment. Using an exposure equivalent to 6.05×10^{20} protons on target, 33 ν_{e} candidates are observed with a background of 8.2±0.8 (syst.). Combined with the latest NOvA ν_{µ} disappearance data and external constraints from reactor experiments on sin^{2}2θ_{13}, the hypothesis of inverted mass hierarchy with θ_{23} in the lower octant is disfavored at greater than 93% C.L. for all values of δ_{CP}.

12.
Phys Rev Lett ; 118(15): 151802, 2017 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28452513

RESUMO

This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of 6.05×10^{20} protons on target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal θ_{23} mixing (θ_{23}=π/4). Assuming the normal mass hierarchy, we find Δm_{32}^{2}=(2.67±0.11)×10^{-3} eV^{2} and sin^{2}θ_{23} at the two statistically degenerate values 0.404_{-0.022}^{+0.030} and 0.624_{-0.030}^{+0.022}, both at the 68% confidence level. Our data disfavor the maximal mixing scenario with 2.6σ significance.

13.
Phys Rev Lett ; 117(15): 151803, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768323

RESUMO

We report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a ν_{µ}-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.56×10^{20} protons on target, are analyzed using a phenomenological model with one sterile neutrino. We constrain the mixing parameters θ_{24} and Δm_{41}^{2} and set limits on parameters of the four-dimensional Pontecorvo-Maki-Nakagawa-Sakata matrix, |U_{µ4}|^{2} and |U_{τ4}|^{2}, under the assumption that mixing between ν_{e} and ν_{s} is negligible (|U_{e4}|^{2}=0). No evidence for ν_{µ}→ν_{s} transitions is found and we set a world-leading limit on θ_{24} for values of Δm_{41}^{2}≲1 eV^{2}.

14.
Rev. chil. obstet. ginecol ; 81(5): 411-420, 2016. ilus
Artigo em Espanhol | LILACS | ID: biblio-830152

RESUMO

Se presenta el caso de paciente con ascitis, masa pelviana y CA 125 elevado, sugerentes de cáncer ovárico avanzado. Se realizó laparoscopía que demostró lesiones compatibles con tuberculosis peritoneal. La biopsia laparoscópica de las lesiones demostró granulomas, por lo que no se realizó más cirugía y se inició tratamiento antituberculoso específico con buena respuesta clínica. Se revisa en la literatura tuberculosis peritoneal y su dificultad con el diagnóstico diferencial con cáncer de ovario avanzado.


It is presented the case of a patient with ascites, pelvic mass and elevated CA 125, all suggested of advanced ovarian cancer. It was made a laparoscopy that evidenced lesions of peritoneal tuberculosis. The laparoscopic biopsy of the lesions demostrated granulomas, for that there was no more surgery made and antituberculosis specific treatment was started, with good clinical response. It is revisited in the literature peritoneal tuberculosis and its difficult differential diagnoses with advanced ovarian cancer.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Peritonite Tuberculosa/diagnóstico , Peritonite Tuberculosa/terapia , Antibacterianos/uso terapêutico , Ascite/etiologia , Diagnóstico Diferencial , Laparoscopia , Neoplasias Ovarianas/diagnóstico , Peritonite Tuberculosa/complicações
15.
J Neonatal Perinatal Med ; 7(3): 247-51, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25322992

RESUMO

Persistent pulmonary hypertension of the newborn (PPHN) results from disruption of the normal fetal-neonatal circulatory transition and may be associated with meconium aspiration, group B streptococcal sepsis, pneumonia, respiratory distress syndrome, congenital diaphragmatic hernia and pulmonary hypoplasia. Seventeen percent of cases are considered idiopathic since there is no identifiable cause. Although it is recognized that acidosis and hypoxia from any cause in neonates may produce pulmonary vasoconstriction and maintain pulmonary hypertension, PPHN has not been reported in inborn errors of metabolism (IEM) associated with metabolic acidosis like methyl malonic acidemia (MMA). We report the first case in the literature of MMA presenting concomitantly with PPHN. Undiagnosed IEMs, like MMA, could represent a subset of idiopathic cases of PPHN. Infants and neonates have a limited repertoire with which to respond to an overwhelming illness. Because metabolic diseases are rare, they are considered only after excluding more common causes of neonatal distress. PPHN is therefore more likely to be attributed to meconium aspiration, sepsis, pneumonia or respiratory distress syndrome than to an IEM. The advent of expanded newborn screening has made pre-symptomatic diagnosis of several IEMs including MMA possible. However, not all IEMs are identified, and in some instances, an infant who has an IEM may become ill before the results of the newborn screen become available. Early diagnosis of IEM is crucial to prevent catastrophic consequences and the awareness of an association with PPHN would lead to an aggressive search of an underlying IEM and its management.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Síndrome da Persistência do Padrão de Circulação Fetal/etiologia , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Feminino , Humanos , Recém-Nascido , Síndrome da Persistência do Padrão de Circulação Fetal/diagnóstico
16.
Phys Rev Lett ; 112(19): 191801, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24877929

RESUMO

We report on a new analysis of neutrino oscillations in MINOS using the complete set of accelerator and atmospheric data. The analysis combines the ν(µ) disappearance and ν(e) appearance data using the three-flavor formalism. We measure |Δm(32)(2)| = [2.28-2.46] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.35-0.65 (90% C.L.) in the normal hierarchy, and |Δm(32)(2)| = [2.32-2.53] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.34-0.67 (90% C.L.) in the inverted hierarchy. The data also constrain δ(CP), the θ(23} octant degeneracy and the mass hierarchy; we disfavor 36% (11%) of this three-parameter space at 68% (90%) C.L.

17.
Mol Genet Metab ; 112(3): 242-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24797656

RESUMO

Biotinidase deficiency (BD) is an autosomal recessive disorder resulting in the inability to recycle the vitamin biotin. Individuals with biotinidase deficiency can develop neurological and cutaneous symptoms if they are not treated with biotin. To date, more than 165 mutations in the biotinidase gene (BTD) have been reported. Essentially all the mutations result in enzymatic activities with less than 10% of mean normal serum enzyme activity (profound biotinidase deficiency) with the exception of the c.1330G>C (p.D444H) mutation, which results in an enzyme having 50% of mean normal serum activity and causes partial biotinidase deficiency (10-30% of mean normal serum biotinidase activity) if there is a mutation for profound biotinidase deficiency on the second allele. We now reported eight novel mutations in ten children identified by newborn screening in Michigan from 1988 to the end of 2012. Interestingly, one intronic mutation, c.310-15delT, results in an approximately two-fold down-regulation of BTD mRNA expression by Quantitative real-time reverse-transcription PCR (qRT-PCR). This is the first report of an intronic mutation in the BTD gene with demonstration of its effect on enzymatic activity by altering mRNA expression. This study identified three other mutations likely to cause partial biotinidase deficiency. These results emphasize the importance of full gene sequencing of BTD on patients with biotinidase deficiency to better understand the genotype and phenotype correlation in the future.


Assuntos
Deficiência de Biotinidase/diagnóstico , Deficiência de Biotinidase/genética , Biotinidase/genética , Íntrons , Mutação , RNA Mensageiro , Biotinidase/metabolismo , Análise Mutacional de DNA , Ativação Enzimática , Regulação da Expressão Gênica , Ordem dos Genes , Loci Gênicos , Humanos , Recém-Nascido , Michigan , Triagem Neonatal , RNA Mensageiro/genética
18.
Phys Rev Lett ; 113(26): 262506, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615318

RESUMO

The electromagnetic polarizabilities of the nucleon are fundamental properties that describe its response to external electric and magnetic fields. They can be extracted from Compton-scattering data-and have been, with good accuracy, in the case of the proton. In contradistinction, information for the neutron requires the use of Compton scattering from nuclear targets. Here, we report a new measurement of elastic photon scattering from deuterium using quasimonoenergetic tagged photons at the MAX IV Laboratory in Lund, Sweden. These first new data in more than a decade effectively double the world data set. Their energy range overlaps with previous experiments and extends it by 20 MeV to higher energies. An analysis using chiral effective field theory with dynamical Δ(1232) degrees of freedom shows the data are consistent with and within the world data set. After demonstrating that the fit is consistent with the Baldin sum rule, extracting values for the isoscalar nucleon polarizabilities, and combining them with a recent result for the proton, we obtain the neutron polarizabilities as αn=[11.55±1.25(stat)±0.2(BSR)±0.8(th)]×10(-4) fm(3) and ßn=[3.65∓1.25(stat)±0.2(BSR)∓0.8(th)]×10(-4) fm(3), with χ(2)=45.2 for 44 degrees of freedom.

19.
Phys Rev Lett ; 110(25): 251801, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23829728

RESUMO

We report measurements of oscillation parameters from ν(µ) and ν(µ) disappearance using beam and atmospheric data from MINOS. The data comprise exposures of 10.71×10(20) protons on target in the ν(µ)-dominated beam, 3.36×10(20) protons on target in the ν(µ)-enhanced beam, and 37.88 kton yr of atmospheric neutrinos. Assuming identical ν and ν oscillation parameters, we measure |Δm2| = (2.41(-0.10)(+0.09))×10(-3) eV2 and sin2(2θ) = 0.950(-0.036)(+0.035). Allowing independent ν and ν oscillations, we measure antineutrino parameters of |Δm2| = (2.50(-0.25)(+0.23))×10(-3) eV2 and sin2(2θ) = 0.97(-0.08)(+0.03), with minimal change to the neutrino parameters.

20.
Phys Rev Lett ; 110(17): 171801, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23679706

RESUMO

We report on ν(e) and ν(e) appearance in ν(µ) and ν(µ) beams using the full MINOS data sample. The comparison of these ν(e) and ν(e) appearance data at a 735 km baseline with θ13 measurements by reactor experiments probes δ, the θ23 octant degeneracy, and the mass hierarchy. This analysis is the first use of this technique and includes the first accelerator long-baseline search for ν(µ) → ν(e). Our data disfavor 31% (5%) of the three-parameter space defined by δ, the octant of the θ23, and the mass hierarchy at the 68% (90%) C.L. We measure a value of 2sin(2)(2θ13)sin(2)(θ23) that is consistent with reactor experiments.

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