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Neutrinos exist in one of three types or 'flavours'-electron, muon and tau neutrinos-and oscillate from one flavour to another when propagating through space. This phenomena is one of the few that cannot be described using the standard model of particle physics (reviewed in ref. 1), and so its experimental study can provide new insight into the nature of our Universe (reviewed in ref. 2). Neutrinos oscillate as a function of their propagation distance (L) divided by their energy (E). Therefore, experiments extract oscillation parameters by measuring their energy distribution at different locations. As accelerator-based oscillation experiments cannot directly measure E, the interpretation of these experiments relies heavily on phenomenological models of neutrino-nucleus interactions to infer E. Here we exploit the similarity of electron-nucleus and neutrino-nucleus interactions, and use electron scattering data with known beam energies to test energy reconstruction methods and interaction models. We find that even in simple interactions where no pions are detected, only a small fraction of events reconstruct to the correct incident energy. More importantly, widely used interaction models reproduce the reconstructed energy distribution only qualitatively and the quality of the reproduction varies strongly with beam energy. This shows both the need and the pathway to improve current models to meet the requirements of next-generation, high-precision experiments such as Hyper-Kamiokande (Japan)3 and DUNE (USA)4.
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We report the first measurement of monoenergetic muon neutrino charged current interactions. MiniBooNE has isolated 236 MeV muon neutrino events originating from charged kaon decay at rest (K^{+}âµ^{+}ν_{µ}) at the NuMI beamline absorber. These signal ν_{µ}-carbon events are distinguished from primarily pion decay in flight ν_{µ} and ν[over ¯]_{µ} backgrounds produced at the target station and decay pipe using their arrival time and reconstructed muon energy. The significance of the signal observation is at the 3.9σ level. The muon kinetic energy, neutrino-nucleus energy transfer (ω=E_{ν}-E_{µ}), and total cross section for these events are extracted. This result is the first known-energy, weak-interaction-only probe of the nucleus to yield a measurement of ω using neutrinos, a quantity thus far only accessible through electron scattering.
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The MiniBooNE experiment at Fermilab reports results from a search for ¯ν_{µ}â¯ν_{e} oscillations, using a data sample corresponding to 5.66×10²° protons on target. An excess of 20.9±14.0 events is observed in the energy range 475
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BACKGROUND AND PURPOSE: The glycosaminoglycan heparin has anti-inflammatory activity and is exclusively found in mast cells, which are localized within airway smooth muscle (ASM) bundles of asthmatic airways. Interleukin (IL)-13 induces the production of multiple inflammatory mediators from ASM including the eosinophil chemoattractant chemokine, eotaxin-1. Heparin and related glycosaminoglycan polymers having structurally heterogeneous polysaccharide side chains that varied in molecular weight, sulphation and anionic charge were used to identify features of the heparin molecule linked to anti-inflammatory activity. EXPERIMENTAL APPROACH: Cultured human ASM cells were stimulated with interleukin (IL)-13 in the absence or presence of heparin and related polymers. Eotaxin-1 was quantified using chemokine antibody arrays and ELISA. KEY RESULTS: Unfractionated heparin attenuated IL-13-dependent eotaxin-1 production and this effect was reproduced with low molecular weight heparins (3 and 6 kDa), demonstrating a minimum activity fragment of at least 3 kDa. N-desulphated, 20% re-N-acetylated heparin (anticoagulant) was ineffective against IL-13-dependent eotaxin-1 production compared with 90% re-N-acetylated (anticoagulant) or O-desulphated (non-anticoagulant) heparin, suggesting a requirement for N-sulphation independent of anticoagulant activity. Other sulphated molecules with variable anionic charge and molecular weight exceeding 3 kDa (dextran sulphate, fucoidan, chondroitin sulphate B) inhibited IL-13-stimulated eotaxin-1 release to varying degrees. However, non-sulphated dextran had no effect. CONCLUSIONS: Inhibition of IL-13-dependent eotaxin-1 release by heparin involved but did not depend upon sulphation, though loss of N-sulphation reduced the attenuating activity, which could be restored by N-acetylation. This anti-inflammatory effect was also partially dependent on anionic charge, but independent of molecular size above 3 kDa and the anticoagulant action of heparin.
Assuntos
Anti-Inflamatórios/farmacologia , Anticoagulantes/farmacologia , Quimiocina CCL11/efeitos dos fármacos , Heparina/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Adulto , Idoso , Ânions/química , Anti-Inflamatórios/química , Anticoagulantes/química , Células Cultivadas , Quimiocina CCL11/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Heparina/química , Heparina de Baixo Peso Molecular/química , Heparina de Baixo Peso Molecular/farmacologia , Humanos , Interleucina-13/farmacologia , Masculino , Pessoa de Meia-Idade , Peso Molecular , Sulfatos/químicaRESUMO
Recognition of facial expressions of emotion was investigated in people with medicated and unmedicated Parkinson's disease (PD) and matched controls (unmedicated PD, n=16; medicated PD, n=20; controls, n=40). Participants in the medicated group showed some visual impairment (impaired contrast sensitivity) and performed less well on perception of unfamiliar face identity, but did not show significant deficits in the perception of sex, gaze direction, or familiar identity from the face. For both Parkinson's disease groups, there was evidence of impaired recognition of facial expressions in comparison to controls. These deficits were more consistently noted in the unmedicated group, who were also found to perform worse than the medicated group at recognising disgust from prototypical facial expressions, and at recognising anger and disgust in computer-manipulated images. Although both Parkinson's disease groups showed impairments of facial expression recognition, the consistently worse recognition of disgust in the unmedicated group is consistent with the hypothesis from previous studies that brain regions modulated by dopaminergic neurons are involved in the recognition of disgust.
Assuntos
Dopaminérgicos/farmacologia , Expressão Facial , Doença de Parkinson/fisiopatologia , Reconhecimento Psicológico/efeitos dos fármacos , Idoso , Estudos de Casos e Controles , Comportamento de Escolha , Sinais (Psicologia) , Aprendizagem por Discriminação , Dopaminérgicos/uso terapêutico , Emoções/fisiologia , Feminino , Percepção de Forma , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/tratamento farmacológico , Reconhecimento Visual de Modelos/efeitos dos fármacos , Sexo , Percepção VisualRESUMO
The present study, involving 972 laying hens divided into 162 groups (n = 6), was aimed at the development of an immunisation protocol for laying hens to produce specific egg yolk antibodies. Recombinant bovine somatotropin (rbst), Escherichia coli pilus antigen K88 (K88), human serum immunoglobulin G (IgG), and low density lipoprotein (LDL) were used as antigens, each at four different doses (rbst, K88, LDL : 1µg, 10µg, 100µg, 1mg ; IgG : 0.5µg, 5µg, 50µg, 0.5mg). Three subcutaneous or intramuscular immunisations were performed at intervals of four weeks. The adjuvant used was either the lipopeptide Pam3Cys-Ser-(Lys)4 (PCSL) or Freund ` s incomplete adjuvant (FIA), in two different doses (PCSL: 0.1 and 0.25mg ; FIA: 0.1 and 0.25ml). In the four antigen control groups, hens were immunised without any adjuvant. In two negative control groups, only physiological saline was injected. The mean egg weight and egg yield were not influenced by the immunisation procedures. An antigen dose of 10-100g per injection was sufficient to induce high specific antibody titres in the egg yolk. The adjuvant efficacy of PCSL and FIA was proved to be the same (p < 0.05 versus antigen control). With PCSL as adjuvant, some groups showed a tendency to produce even higher specific antibody titres than did FIA groups. A second booster often caused a further significant increase in the amounts of specific antibodies, especially with PCSL. Subcutaneous administration of the antigen together with 250µg PCSL, resulted in a significantly higher immune response than when FIA was used.
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The MiniBooNE Collaboration reports initial results from a search for nu(mu)-->nu(e) oscillations. A signal-blind analysis was performed using a data sample corresponding to 3.39x10(20) protons on target. The data are consistent with background prediction across the full range of neutrino energy reconstructed assuming quasielastic scattering, 200
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The MiniBooNE Collaboration reports a search for nu_{micro} and nu[over]_{micro} disappearance in the Deltam;{2} region of 0.5-40 eV;{2}. These measurements are important for constraining models with extra types of neutrinos, extra dimensions, and CPT violation. Fits to the shape of the nu_{micro} and nu[over]_{micro} energy spectra reveal no evidence for disappearance at the 90% confidence level (C.L.) in either mode. The test of nu[over]_{micro} disappearance probes a region below Deltam;{2} = 40 eV;{2} never explored before.
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Using high statistics samples of charged-current numu interactions, the MiniBooNE [corrected] Collaboration reports a measurement of the single-charged-pion production to quasielastic cross section ratio on mineral oil (CH2), both with and without corrections for hadron reinteractions in the target nucleus. The result is provided as a function of neutrino energy in the range 0.4 GeV
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We report the first observation of off-axis neutrino interactions in the MiniBooNE detector from the NuMI beam line at Fermilab. The MiniBooNE detector is located 745 m from the NuMI production target, at 110 mrad angle (6.3 degrees) with respect to the NuMI beam axis. Samples of charged-current quasielastic numicro and nue interactions are analyzed and found to be in agreement with expectation. This provides a direct verification of the expected pion and kaon contributions to the neutrino flux and validates the modeling of the NuMI off-axis beam.
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The MiniBooNE Collaboration observes unexplained electronlike events in the reconstructed neutrino energy range from 200 to 475 MeV. With 6.46x10;{20} protons on target, 544 electronlike events are observed in this energy range, compared to an expectation of 415.2+/-43.4 events, corresponding to an excess of 128.8+/-20.4+/-38.3 events. The shape of the excess in several kinematic variables is consistent with being due to either nu_{e} and nu[over ]_{e} charged-current scattering or nu_{mu} neutral-current scattering with a photon in the final state. No significant excess of events is observed in the reconstructed neutrino energy range from 475 to 1250 MeV, where 408 events are observed compared to an expectation of 385.9+/-35.7 events.
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The observation of neutrino oscillations is clear evidence for physics beyond the standard model. To make precise measurements of this phenomenon, neutrino oscillation experiments, including MiniBooNE, require an accurate description of neutrino charged current quasielastic (CCQE) cross sections to predict signal samples. Using a high-statistics sample of nu_(mu) CCQE events, MiniBooNE finds that a simple Fermi gas model, with appropriate adjustments, accurately characterizes the CCQE events observed in a carbon-based detector. The extracted parameters include an effective axial mass, M_(A)(eff)=1.23+/-0.20 GeV, that describes the four-momentum dependence of the axial-vector form factor of the nucleon, and a Pauli-suppression parameter, kappa=1.019+/-0.011. Such a modified Fermi gas model may also be used by future accelerator-based experiments measuring neutrino oscillations on nuclear targets.
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Stretch is known to stimulate myometrial hyperplasia and hypertrophy in early pregnancy and uterine contraction at term. We propose that transduction of the stretch signal involves alteration of intracellular calcium signalling, including changes in transient receptor potential canonical (TRPC) isoform expression. The aim of the present study was to investigate the effect of prolonged mechanical (tonic) stretch in vitro on human myometrial smooth muscle cell calcium signalling and TRPC expression. Cells were cultured from myometrial biopsies, obtained from women undergoing elective Caesarean section at term, grown on Flexiplates and subjected to 25% tonic mechanical stretch for 1, 4 and 14 h. Time-matched control cells were not stretched. Mechanical stretch (14 h) increased basal calcium entry and cyclopiazonic acid (CPA)-induced calcium/Mn(2+) entry (P < 0.05) in Fura-2 loaded cells. The calcium selectivity of CPA-thapsigarin induced inward currents, measured by patch clamp electrophysiology, was also increased in stretched cells compared with control cells (P < 0.05). Real time PCR and Western blot data demonstrated that TRPC3 and TRPC4 mRNA and TRPC3 protein expression were increased by stretch (P < 0.05), respectively. These data support the hypothesis that uterine stretch modulates uterine growth and contractility in pregnancy via alterations in calcium signalling.
Assuntos
Sinalização do Cálcio , Mecanotransdução Celular , Miócitos de Músculo Liso/metabolismo , Miométrio/metabolismo , Canais de Cátion TRPC/metabolismo , Contração Uterina , Western Blotting , Sinalização do Cálcio/efeitos dos fármacos , ATPases Transportadoras de Cálcio/antagonistas & inibidores , ATPases Transportadoras de Cálcio/metabolismo , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Indóis/farmacologia , Mecanotransdução Celular/efeitos dos fármacos , Potenciais da Membrana , Miócitos de Músculo Liso/efeitos dos fármacos , Miométrio/citologia , Miométrio/efeitos dos fármacos , Técnicas de Patch-Clamp , Gravidez , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Canais de Cátion TRPC/genética , Tapsigargina/farmacologia , Fatores de Tempo , Regulação para CimaRESUMO
The left lateral frontopolar (LFP) cortex showed dimension change-related activation in previous event-related functional magnetic resonance imaging studies of visual singleton feature search with non-brain-lesioned participants. Here, we tested the hypothesis that LFP actively supports changes of attention from the old to the new target-defining dimension in singleton feature search. Singleton detection was selectively slowed in this task when the target-defining dimension changed in patients with left LFP lesions, compared with patients with frontomedian lesions as well as with matched controls without brain lesions. We discuss a potential role of LFP in change detection when the optimal allocation of dimension-based attention is not clearly defined by the task.
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Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Córtex Pré-Frontal/lesões , Percepção Visual/fisiologia , Adulto , Idoso , Aneurisma Roto/psicologia , Atenção/fisiologia , Lesões Encefálicas/psicologia , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/psicologia , Transtornos Cognitivos/patologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Aneurisma Intracraniano/psicologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Córtex Pré-Frontal/patologiaRESUMO
The MiniBooNE Collaboration reports first results of a search for nu e appearance in a nu mu beam. With two largely independent analyses, we observe no significant excess of events above the background for reconstructed neutrino energies above 475 MeV. The data are consistent with no oscillations within a two-neutrino appearance-only oscillation model.