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1.
Phys Rev Lett ; 132(15): 151801, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38683006

ABSTRACT

We present a measurement of η production from neutrino interactions on argon with the MicroBooNE detector. The modeling of resonant neutrino interactions on argon is a critical aspect of the neutrino oscillation physics program being carried out by the DUNE and Short Baseline Neutrino programs. η production in neutrino interactions provides a powerful new probe of resonant interactions, complementary to pion channels, and is particularly suited to the study of higher-order resonances beyond the Δ(1232). We measure a flux-integrated cross section for neutrino-induced η production on argon of 3.22±0.84(stat)±0.86(syst) 10^{-41} cm^{2}/nucleon. By demonstrating the successful reconstruction of the two photons resulting from η production, this analysis enables a novel calibration technique for electromagnetic showers in GeV accelerator neutrino experiments.

2.
Phys Rev Lett ; 131(10): 101802, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37739352

ABSTRACT

We report the first measurement of flux-integrated double-differential quasielasticlike neutrino-argon cross sections, which have been made using the Booster Neutrino Beam and the MicroBooNE detector at Fermi National Accelerator Laboratory. The data are presented as a function of kinematic imbalance variables which are sensitive to nuclear ground-state distributions and hadronic reinteraction processes. We find that the measured cross sections in different phase-space regions are sensitive to different nuclear effects. Therefore, they enable the impact of specific nuclear effects on the neutrino-nucleus interaction to be isolated more completely than was possible using previous single-differential cross section measurements. Our results provide precision data to help test and improve neutrino-nucleus interaction models. They further support ongoing neutrino-oscillation studies by establishing phase-space regions where precise reaction modeling has already been achieved.

3.
Eur Phys J C Part Fields ; 83(6): 467, 2023.
Article in English | MEDLINE | ID: mdl-37303462

ABSTRACT

The ICARUS collaboration employed the 760-ton T600 detector in a successful 3-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous νe appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV2. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS then started its operations collecting the first neutrino events from the booster neutrino beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022. The first goal of the ICARUS data taking will be a study to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurement of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will search for evidence of sterile neutrinos jointly with the Short-Baseline Near Detector, within the Short-Baseline Neutrino program. In this paper, the main activities carried out during the overhauling and installation phases are highlighted. Preliminary technical results from the ICARUS commissioning data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and of capability to select and reconstruct neutrino events.

4.
Phys Rev Lett ; 130(23): 231802, 2023 Jun 09.
Article in English | MEDLINE | ID: mdl-37354393

ABSTRACT

We present the first measurement of the cross section of Cabibbo-suppressed Λ baryon production, using data collected with the MicroBooNE detector when exposed to the neutrinos from the main injector beam at the Fermi National Accelerator Laboratory. The data analyzed correspond to 2.2×10^{20} protons on target running in neutrino mode, and 4.9×10^{20} protons on target running in anti-neutrino mode. An automated selection is combined with hand scanning, with the former identifying five candidate Λ production events when the signal was unblinded, consistent with the GENIE prediction of 5.3±1.1 events. Several scanners were employed, selecting between three and five events, compared with a prediction from a blinded Monte Carlo simulation study of 3.7±1.0 events. Restricting the phase space to only include Λ baryons that decay above MicroBooNE's detection thresholds, we obtain a flux averaged cross section of 2.0_{-1.7}^{+2.2}×10^{-40} cm^{2}/Ar, where statistical and systematic uncertainties are combined.


Subject(s)
Mesons , Protons , Computer Simulation , Monte Carlo Method
5.
Phys Rev Lett ; 130(1): 011801, 2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36669216

ABSTRACT

We present a search for eV-scale sterile neutrino oscillations in the MicroBooNE liquid argon detector, simultaneously considering all possible appearance and disappearance effects within the 3+1 active-to-sterile neutrino oscillation framework. We analyze the neutrino candidate events for the recent measurements of charged-current ν_{e} and ν_{µ} interactions in the MicroBooNE detector, using data corresponding to an exposure of 6.37×10^{20} protons on target from the Fermilab booster neutrino beam. We observe no evidence of light sterile neutrino oscillations and derive exclusion contours at the 95% confidence level in the plane of the mass-squared splitting Δm_{41}^{2} and the sterile neutrino mixing angles θ_{µe} and θ_{ee}, excluding part of the parameter space allowed by experimental anomalies. Cancellation of ν_{e} appearance and ν_{e} disappearance effects due to the full 3+1 treatment of the analysis leads to a degeneracy when determining the oscillation parameters, which is discussed in this Letter and will be addressed by future analyses.

6.
Phys Rev Lett ; 128(24): 241801, 2022 Jun 17.
Article in English | MEDLINE | ID: mdl-35776450

ABSTRACT

We present a measurement of ν_{e} interactions from the Fermilab Booster Neutrino Beam using the MicroBooNE liquid argon time projection chamber to address the nature of the excess of low energy interactions observed by the MiniBooNE Collaboration. Three independent ν_{e} searches are performed across multiple single electron final states, including an exclusive search for two-body scattering events with a single proton, a semi-inclusive search for pionless events, and a fully inclusive search for events containing all hadronic final states. With differing signal topologies, statistics, backgrounds, reconstruction algorithms, and analysis approaches, the results are found to be either consistent with or modestly lower than the nominal ν_{e} rate expectations from the Booster Neutrino Beam and no excess of ν_{e} events is observed.

7.
Phys Rev Lett ; 128(15): 151801, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35499871

ABSTRACT

We report a measurement of the energy-dependent total charged-current cross section σ(E_{ν}) for inclusive muon neutrinos scattering on argon, as well as measurements of flux-averaged differential cross sections as a function of muon energy and hadronic energy transfer (ν). Data corresponding to 5.3×10^{19} protons on target of exposure were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab booster neutrino beam with a mean neutrino energy of approximately 0.8 GeV. The mapping between the true neutrino energy E_{ν} and reconstructed neutrino energy E_{ν}^{rec} and between the energy transfer ν and reconstructed hadronic energy E_{had}^{rec} are validated by comparing the data and Monte Carlo (MC) predictions. In particular, the modeling of the missing hadronic energy and its associated uncertainties are verified by a new method that compares the E_{had}^{rec} distributions between data and a MC prediction after constraining the reconstructed muon kinematic distributions, energy, and polar angle to those of data. The success of this validation gives confidence that the missing energy in the MicroBooNE detector is well modeled and underpins first-time measurements of both the total cross section σ(E_{ν}) and the differential cross section dσ/dν on argon.

8.
Phys Rev Lett ; 128(11): 111801, 2022 Mar 18.
Article in English | MEDLINE | ID: mdl-35363017

ABSTRACT

We report results from a search for neutrino-induced neutral current (NC) resonant Δ(1232) baryon production followed by Δ radiative decay, with a ⟨0.8⟩ GeV neutrino beam. Data corresponding to MicroBooNE's first three years of operations (6.80×10^{20} protons on target) are used to select single-photon events with one or zero protons and without charged leptons in the final state (1γ1p and 1γ0p, respectively). The background is constrained via an in situ high-purity measurement of NC π^{0} events, made possible via dedicated 2γ1p and 2γ0p selections. A total of 16 and 153 events are observed for the 1γ1p and 1γ0p selections, respectively, compared to a constrained background prediction of 20.5±3.65(syst) and 145.1±13.8(syst) events. The data lead to a bound on an anomalous enhancement of the normalization of NC Δ radiative decay of less than 2.3 times the predicted nominal rate for this process at the 90% confidence level (C.L.). The measurement disfavors a candidate photon interpretation of the MiniBooNE low-energy excess as a factor of 3.18 times the nominal NC Δ radiative decay rate at the 94.8% C.L., in favor of the nominal prediction, and represents a greater than 50-fold improvement over the world's best limit on single-photon production in NC interactions in the sub-GeV neutrino energy range.

9.
Phys Rev Lett ; 127(15): 151803, 2021 Oct 08.
Article in English | MEDLINE | ID: mdl-34678031

ABSTRACT

We present a search for the decays of a neutral scalar boson produced by kaons decaying at rest, in the context of the Higgs portal model, using the MicroBooNE detector. We analyze data triggered in time with the Fermilab NuMI neutrino beam spill, with an exposure of 1.93×10^{20} protons on target. We look for monoenergetic scalars that come from the direction of the NuMI hadron absorber, at a distance of 100 m from the detector, and decay to electron-positron pairs. We observe one candidate event, with a standard model background prediction of 1.9±0.8. We set an upper limit on the scalar-Higgs mixing angle of θ<(3.3-4.6)×10^{-4} at the 95% confidence level for scalar boson masses in the range (100-200) MeV/c^{2}. We exclude, at the 95% confidence level, the remaining model parameters required to explain the central value of a possible excess of K_{L}^{0}→π^{0}νν[over ¯] decays reported by the KOTO collaboration. We also provide a model-independent limit on a new boson X produced in K→πX decays and decaying to e^{+}e^{-}.

10.
Phys Rev Lett ; 125(20): 201803, 2020 Nov 13.
Article in English | MEDLINE | ID: mdl-33258649

ABSTRACT

We report on the first measurement of flux-integrated single differential cross sections for charged-current (CC) muon neutrino (ν_{µ}) scattering on argon with a muon and a proton in the final state, ^{40}Ar (ν_{µ},µp)X. The measurement was carried out using the Booster Neutrino Beam at Fermi National Accelerator Laboratory and the MicroBooNE liquid argon time projection chamber detector with an exposure of 4.59×10^{19} protons on target. Events are selected to enhance the contribution of CC quasielastic (CCQE) interactions. The data are reported in terms of a total cross section as well as single differential cross sections in final state muon and proton kinematics. We measure the integrated per-nucleus CCQE-like cross section (i.e., for interactions leading to a muon, one proton, and no pions above detection threshold) of (4.93±0.76_{stat}±1.29_{sys})×10^{-38} cm^{2}, in good agreement with theoretical calculations. The single differential cross sections are also in overall good agreement with theoretical predictions, except at very forward muon scattering angles that correspond to low-momentum-transfer events.

11.
Phys Rev Lett ; 123(13): 131801, 2019 Sep 27.
Article in English | MEDLINE | ID: mdl-31697542

ABSTRACT

We report the first measurement of the double-differential and total muon neutrino charged current inclusive cross sections on argon at a mean neutrino energy of 0.8 GeV. Data were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab Booster neutrino beam and correspond to 1.6×10^{20} protons on target of exposure. The measured differential cross sections are presented as a function of muon momentum, using multiple Coulomb scattering as a momentum measurement technique, and the muon angle with respect to the beam direction. We compare the measured cross sections to multiple neutrino event generators and find better agreement with those containing more complete treatment of quasielastic scattering processes at low Q^{2}. The total flux integrated cross section is measured to be 0.693±0.010(stat)±0.165(syst)×10^{-38} cm^{2}.

12.
Inf. psiquiátr ; (236): 29-47, abr.-jun. 2019. tab
Article in Spanish | IBECS | ID: ibc-188432

ABSTRACT

Introducción: En personas con Discapacidad Intelectual (DI) que presentan alteración de la conductwa es frecuente el uso de psicofármacos. Estos fármacos pueden provocar efectos secundarios. Así, la elevación de prolactina está frecuentemente asociada al uso de antipsicóticos y puede generar problemas clínicos. Objetivo: Conocer el nivel de prolactina en un grupo de personas con DI y alteración de la conducta que toman psicofármacos. Conocer su relación con las distintas variables: tipo de fármaco, sexo, edad, grado de discapacidad intelectual y diagnósticos psiquiátricos concurrentes. Población: 80 personas con discapacidad intelectual y alteración de la conducta ingresadas en un centro residencial. Edad media 50 años.53 mujeres, 27 hombres. El 38.8% presentan una DI moderada, el 33.8% leve, el 25% severa y el 2.5% no especificada. Método: Prueba analítica para determinar el nivel de prolactina. Tratamiento farmacológico de cada paciente. Estudiar diferencias significativas entre nivel de prolactina y sexo, edad, grado de DI, diagnósticos psiquiátricos concurrentes, y diferentes fármacos. Resultados: El 78.8% de los pacientes estudiados toma antipsicóticos, de los que el 52.4% toma uno y el 47.6% toma dos o más. El 54% fueron tratados con antipsicóticos de 2ª generación. El nivel medio de prolactina fue en monoterapia de 38.9 ng/ml y en politerapia de 49.4 ng/ml; antipsicóticos de 2ªgeneración: 44.6 ng/ml, antipsicóticos de 1ª generación: 43.1 ng/ml. Además, el 63.8% toma benzodiacepinas y el 58.8% antiepilépticos. Existen diferencias significativas en el nivel medio de prolactina y consumo de antipsicóticos y benzodiacepinas, pero no con los diferentes tipos de antipsicóticos, o con tomar uno o más, o con cada uno de los distintos fármacos. Realizada una regresión logística para predecir niveles de prolactina elevados, las benzodiacepinas presentan una razón de odds 3.02 y tomar antipsicóticos una razón de odds de 12.70. Conclusiones: El nivel de prolactina elevado está asociado a la toma de antipsicóticos y de benzodiacepinas. La toma de antipsicóticos predice una posibilidad de elevar la prolactina de 12.7 veces, que el no tomarlos, y la toma de benzodiacepinas de 3.02 veces superior


Introduction: In people with Intellectual Disability (ID) who exhibit behavior disorders, the use of psychoactive drugs is frequent. These medications can cause side effects. Thus, the elevation of prolactin is frequently associated with the use of antipsychotics and can generate clinical problems. Objective: To know the level of prolactin in a group of people with ID and behavior alteration who take psychotropic drugs. Acknowledge the relation with different variables: type of drug, gender, age, degree of intellectual disability and comorbid psychiatric diagnoses. Population: 80 people with intellectual disabilities and behavior disorders located in a residential centre. Average age 50 years.53 women, 27 men. 38.8% have moderate ID, 33.8% mild, 25% severe and 2.5% unspecified. Method: Analytical test to determine prolactin serum levels. Pharmacological treatment of each patient. Study significant differences between prolactin level and sex, age, degree of ID, concurrent psychiatric diagnoses, and different drugs. Results: 78.8% of patients studied take antipsychotics, of which 52.4% take one and 47.6% take two or more. 54% were treated with 2nd generation antipsychotics. The mean level of prolactin was of 38.9 ng/ml in monotherapy and of 49.4 ng/ml in polytherapy; 2nd generation antipsychotics: 44.6 ng / ml, 1st generation antipsychotics: 43.1 ng / ml. In addition, 63.8% take benzodiazepines and 58.8% antiepileptic drugs. There are significant differences in the mean level of prolactin and consumption of antipsychotics and benzodiazepines, but not with the different types of antipsychotics, or with taking one or more, or with each of the different drugs. A logistic regression was performed to predict elevated prolactin levels, benzodiazepines presented an odds ratio of 3.02 and antipsychotics, an odds ratio of 12.70. Conclusions: The elevation of prolactin is associated with the taking of antipsychotics and benzodiazepines. Taking antipsychotics predicts a possibility of elevating prolactin by 12.7 times, than not taking them, and taking benzodiazepines by 3.02 times higher


Subject(s)
Humans , Male , Female , Middle Aged , Hyperprolactinemia/chemically induced , Intellectual Disability/complications , Antipsychotic Agents/administration & dosage , Psychotropic Drugs/administration & dosage , Intellectual Disability/psychology , Prolactin/therapeutic use , Benzodiazepines/therapeutic use , Logistic Models , Odds Ratio , Anticonvulsants/therapeutic use , Psychopharmacology
13.
Mol Biol Rep ; 36(6): 1311-21, 2009 Jul.
Article in English | MEDLINE | ID: mdl-18636236

ABSTRACT

We have isolated and characterized the gene encoding a Drosophila melanogaster homolog of Caenorhabditis elegans UNC-51 (uncoordinated movement-51): Pegarn. Developmental Northern blot shows the Pegarn gene is expressed at all stages of development. The protein is detected throughout the Drosophila third instar larval central nervous system (CNS) in axons projecting out from the ventral ganglion and in the optic anlagen of the optic lobe. Heterozygous Pegarn mutant embryos show defects in larval axonal neuronal patterning, but survive to adulthood. Homozygous mutants have an even more deformed pattern of neuronal development and do not survive through the larval stages. The data from this research suggest the critical roles of Pegarn in CNS and PNS axonal formation in Drosophila melanogaster and indicates its similar role in other multicellular species.


Subject(s)
Drosophila Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Animals , Autophagy-Related Protein-1 Homolog , Axons/chemistry , Caenorhabditis elegans Proteins , Drosophila Proteins/analysis , Embryo, Nonmammalian , Gene Expression Regulation, Developmental , Life Cycle Stages/genetics , Neurons/chemistry , Neurons/ultrastructure , Protein Serine-Threonine Kinases/analysis , Sequence Homology
14.
Infect Immun ; 67(5): 2522-30, 1999 May.
Article in English | MEDLINE | ID: mdl-10225916

ABSTRACT

The Taenia crassiceps recombinant antigen KETc7 has been shown to be effective as a vaccine against experimental murine cysticercosis, a laboratory model used to test potentially promising molecules against porcine Taenia solium cysticercosis. Based on the deduced amino acid sequence of this proline-rich polypeptide, three fragments, GK-1, GK-2, and GK-3, were chemically synthesized in linear form. Of the three peptides, only GK-1 induced sterile protection against T. crassiceps cysticercosis in 40 to 70% of BALB/cAnN male mice. GK-1 is an 18-amino-acid peptide which contains at least one B-cell epitope, as demonstrated by its ability to induce an antibody response to the peptide and T. crassiceps antigen without need of a carrier protein. Immunofluorescence studies revealed that anti-GK1 antibodies strongly react with the native protein in the tegument of T. crassiceps and also with anatomical structures of T. solium eggs, oncospheres, cysticercus, and tapeworm. GK-1 also contains at least one T-cell epitope, capable of stimulating the proliferation of CD8(+) and to a lower extent CD4(+) T cells primed either with the free peptide or T. crassiceps total antigen. The supernatant of the stimulated cells contained high levels of gamma interferon and low levels of interleukin-4. Similar results were obtained with T cells tested for intracellular cytokine production, an indication of the peptide's capacity to induce an inflammatory response. The remarkable protection induced by GK-1 immunization, its physicochemical properties, and its presence in all developmental stages of T. solium point to this synthetic peptide as a strong candidate in the construction of a synthetic vaccine against T. solium pig cysticercosis.


Subject(s)
Cysticercosis/immunology , Cysticercosis/prevention & control , Taenia/immunology , Vaccines, Synthetic/pharmacology , Amino Acid Sequence , Animals , Antibodies, Helminth/blood , Antigens, Helminth/chemistry , Antigens, Helminth/genetics , B-Lymphocytes/immunology , Epitopes/chemistry , Epitopes/genetics , Helminth Proteins/chemistry , Helminth Proteins/genetics , Helminth Proteins/immunology , Immunization , Interferon-gamma/biosynthesis , Interleukin-4/biosynthesis , Lymphocyte Activation , Male , Mice , Mice, Inbred BALB C , Models, Molecular , Molecular Sequence Data , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Species Specificity , T-Lymphocytes/immunology , Taenia/genetics , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology
15.
J Steroid Biochem Mol Biol ; 52(6): 575-80, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7779761

ABSTRACT

Female mice are more susceptible to Taenia crassiceps (TC) infection than males. However, after a month parasite load increases massively in both genders reaching thousands of parasites per host. The possibility of hormonal changes in the infected mice was envisaged. Sex hormones levels were assayed after different periods of infection, the parasites present in the peritoneal cavity were collected and gonads, uterus and seminal vesicles were weighed. In male mice, serum estradiol increased to levels 200 times their normal values whilst those of testosterone decreased 90% relative to controls. The weight of seminal vesicles was significantly diminished. Infected female mice also showed a slight increase in estrogen blood levels after 8 weeks of infection and the weight of the uterus was significantly increased relative to controls. Serum estradiol and testosterone were almost undetectable after gonadectomy. Cytokines such as IL-6 are capable of stimulating aromatase activity and we found that splenocytes from infected mice produced amounts of IL-6 higher than control as measured by ELISA. In conclusion T. crassiceps infection triggers a feminization process in the infected hosts. The gonads are required for the parasite to induce higher estrogen synthesis. IL-6 could be involved in the immunoendocrine mechanism used by the parasite to maintain a highly permissive environment for its rapid growth.


Subject(s)
Androgen-Insensitivity Syndrome/etiology , Cysticercosis/complications , Cysticercosis/metabolism , Gonadal Steroid Hormones/metabolism , Androgen-Insensitivity Syndrome/metabolism , Animals , Cysticercosis/pathology , Cysticercus/pathogenicity , Dihydrotestosterone/pharmacology , Estradiol/blood , Female , Interleukin-6/blood , Male , Mice , Mice, Inbred BALB C , Orchiectomy , Organ Size , Ovariectomy , Seminal Vesicles/pathology , Sex Characteristics , Testosterone/blood , Testosterone/pharmacology , Uterus/pathology
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