Neutrino-Induced Coherent π

MINERvA has measured the ν_{µ}-induced coherent π^{+} cross section simultaneously in hydrocarbon (CH), graphite (C), iron (Fe), and lead (Pb) targets using neutrinos from 2 to 20 GeV. The measurements exceed the predictions of the Rein-Sehgal and Berger-Sehgal PCAC based models at multi-GeV ν_{µ} energies and at produced π^{+} energies and angles, E_{π}>1 GeV and θ_{π}<10°. Measurements of the cross-section ratios of Fe and Pb relative to CH reveal the effective A scaling to increase from an approximate A^{1/3} scaling at few GeV to an A^{2/3} scaling for E_{ν}>10 GeV.

Simultaneous Measurement of Muon Neutrino ν_{µ} Charged-Current Single π

Neutrino-induced charged-current single π^{+} production in the Δ(1232) resonance region is of considerable interest to accelerator-based neutrino oscillation experiments. In this Letter, high statistic differential cross sections are reported for the semiexclusive reaction ν_{µ}A→µ^{-}π^{+}+ nucleon(s) on scintillator, carbon, water, iron, and lead targets recorded by MINERvA using a wideband ν_{µ} beam with ⟨E_{ν}⟩≈6 GeV. Suppression of the cross section at low Q^{2} and enhancement of low T_{π} are observed in both light and heavy nuclear targets compared with phenomenological models used in current neutrino interaction generators. The cross sections per nucleon for iron and lead compared with CH across the kinematic variables probed are 0.8 and 0.5 respectively, a scaling which is also not predicted by current generators.

Simultaneous Measurement of ν_{µ} Quasielasticlike Cross Sections on CH, C, H_{2}O, Fe, and Pb as a Function of Muon Kinematics at MINERvA.

This Letter presents the first simultaneous measurement of the quasielasticlike neutrino-nucleus cross sections on C, water, Fe, Pb, and scintillator (hydrocarbon or CH) as a function of longitudinal and transverse muon momentum. The ratio of cross sections per nucleon between Pb and CH is always above unity and has a characteristic shape as a function of transverse muon momentum that evolves slowly as a function of longitudinal muon momentum. The ratio is constant versus longitudinal momentum within uncertainties above a longitudinal momentum of 4.5 GeV/c. The cross section ratios to CH for C, water, and Fe remain roughly constant with increasing longitudinal momentum, and the ratios between water or C to CH do not have any significant deviation from unity. Both the overall cross section level and the shape for Pb and Fe as a function of transverse muon momentum are not reproduced by current neutrino event generators. These measurements provide a direct test of nuclear effects in quasielasticlike interactions, which are major contributors to long-baseline neutrino oscillation data samples.

Measurement of the axial vector form factor from antineutrino-proton scattering.

Scattering of high energy particles from nucleons probes their structure, as was done in the experiments that established the non-zero size of the proton using electron beams1. The use of charged leptons as scattering probes enables measuring the distribution of electric charges, which is encoded in the vector form factors of the nucleon2. Scattering weakly interacting neutrinos gives the opportunity to measure both vector and axial vector form factors of the nucleon, providing an additional, complementary probe of their structure. The nucleon transition axial form factor, FA, can be measured from neutrino scattering from free nucleons, νµn → µ-p and [Formula: see text], as a function of the negative four-momentum transfer squared (Q2). Up to now, FA(Q2) has been extracted from the bound nucleons in neutrino-deuterium scattering3-9, which requires uncertain nuclear corrections10. Here we report the first high-statistics measurement, to our knowledge, of the [Formula: see text] cross-section from the hydrogen atom, using the plastic scintillator target of the MINERvA11 experiment, extracting FA from free proton targets and measuring the nucleon axial charge radius, rA, to be 0.73 ± 0.17 fm. The antineutrino-hydrogen scattering presented here can access the axial form factor without the need for nuclear theory corrections, and enables direct comparisons with the increasingly precise lattice quantum chromodynamics computations12-15. Finally, the tools developed for this analysis and the result presented are substantial advancements in our capabilities to understand the nucleon structure in the weak sector, and also help the current and future neutrino oscillation experiments16-20 to better constrain neutrino interaction models.

Simultaneous Measurement of Proton and Lepton Kinematics in Quasielasticlike ν_{µ}-Hydrocarbon Interactions from 2 to 20 GeV.

Neutrino charged-current quasielastic-like scattering, a reaction category extensively used in neutrino oscillation measurements, probes nuclear effects that govern neutrino-nucleus interactions. This Letter reports the first measurement of the triple-differential cross section for ν_{µ} quasielastic-like reactions using the hydrocarbon medium of the MINERvA detector exposed to a wideband beam spanning 2≤E_{ν}≤20 GeV. The measurement maps the correlations among transverse and longitudinal muon momenta and summed proton kinetic energies, and compares them to predictions from a state-of-art simulation. Discrepancies are observed that likely reflect shortfalls with modeling of pion and nucleon intranuclear scattering and/or spectator nucleon ejection from struck nuclei. The separate determination of leptonic and hadronic variables can inform experimental approaches to neutrino-energy estimation.

[P300 cognitive event-related potentials in the diagnosis and classification of possible Alzheimer-type neurocognitive disorders]. / Potencial relacionado con eventos cognitivos P300 en el diagnóstico y clasificación del trastorno neurocognitivo debido a enfermedad de Alzheimer posible.

INTRODUCTION: The value of the P300 cognitive event-related potential in the diagnosis of Alzheimer subtype neurocognitive disorders is still incipient. Recent studies suggest that combining it with neuropsychological tests by cognitive domains would allow an objective and early characterisation of the cognitive impairment in its initial stages. AIMS: To characterise the electrophysiological patterns in the P300 potential that obtain a discriminatory value for the diagnosis and classification of the neurocognitive disorders with a possible Alzheimer-type aetiology. SUBJECTS AND METHODS: This study examines 39 patients classified, according to the DSM-5, with possible Alzheimer-type minor and major neurocognitive disorders, aged between 50 and 85 years, and 53 control subjects with normal cognitive functions. The P300 potential is registered in the auditory mode, oddball paradigm and centroparietal recording. RESULTS: P300 latency is significantly prolonged in subjects with neurocognitive disorder; there are significant differences in the mean values and confidence intervals between healthy controls and patients. No significant differences are obtained in P300 latency between groups with minor and major neurocognitive disorder. The mean amplitude value decreases in neurocognitive disorder, and the P300 amplitude logarithm of the control groups and those with minor and major neurocognitive disorder reaches significantly different mean values and confidence intervals. CONCLUSIONS: The parameters quantified in the P300 potential can be used as complementary biomarkers to classify the presence and level of cognitive dysfunction with a possible Alzheimer-type aetiology.

TITLE: Potencial relacionado con eventos cognitivos P300 en el diagnóstico y clasificación del trastorno neurocognitivo debido a enfermedad de Alzheimer posible.Introducción. El valor del potencial relacionado con eventos cognitivos P300 en el diagnóstico de los trastornos neurocognitivos subtipo Alzheimer es aún incipiente. Estudios recientes sugieren que su combinación con tests neuropsicológicos por dominios cognitivos permitiría caracterizar de forma objetiva y precoz el déficit cognitivo en sus etapas iniciales. Objetivo. Caracterizar los patrones electrofisiológicos en el potencial P300 que obtengan un valor discriminativo para el diagnóstico y clasificación de los trastornos neurocognitivos de etiología enfermedad de Alzheimer posible. Sujetos y métodos. Se estudia a 39 pacientes clasificados, según el DSM-5, con trastorno neurocognitivo menor y mayor debido a enfermedad de Alzheimer posible, en un rango de edad de 50-85 años, y a 53 sujetos control con funciones cognitivas normales. Se registra el potencial P300 en la modalidad auditiva, paradigma de oddball y registro centroparietal. Resultados. La latencia P300 se prolonga significativamente en los sujetos con trastorno neurocognitivo; sus valores medios e intervalos de confianza son significativamente diferentes entre los controles sanos y los pacientes. No se obtienen diferencias significativas de latencia P300 entre los grupos con trastorno neurocognitivo menor y mayor. El valor medio de amplitud disminuye en el trastorno neurocognitivo, y el logaritmo de amplitud P300 obtiene valores medios e intervalos de confianza significativamente diferentes entre los grupos control y con trastorno neurocognitivo menor y mayor. Conclusiones. Los parámetros cuantificados en el potencial P300 pueden utilizarse como biomarcadores complementarios clasificadores de la presencia y del nivel de la disfunción cognitiva de etiología enfermedad de Alzheimer posible.

High-Statistics Measurement of Neutrino Quasielasticlike Scattering at 6 GeV on a Hydrocarbon Target.

We measure neutrino charged-current quasielasticlike scattering on hydrocarbon at high statistics using the wideband Neutrinos at the Main Injector beam with neutrino energy peaked at 6 GeV. The double-differential cross section is reported in terms of muon longitudinal (p_{∥}) and transverse (p_{⊥}) momentum. Cross section contours versus lepton momentum components are approximately described by a conventional generator-based simulation, however, discrepancies are observed for transverse momenta above 0.5 GeV/c for longitudinal momentum ranges 3-5 and 9-20 GeV/c. The single differential cross section versus momentum transfer squared (dσ/dQ_{QE}^{2}) is measured over a four-decade range of Q^{2} that extends to 10 GeV^{2}. The cross section turnover and falloff in the Q^{2} range 0.3-10 GeV^{2} is not fully reproduced by generator predictions that rely on dipole form factors. Our measurement probes the axial-vector content of the hadronic current and complements the electromagnetic form factor data obtained using electron-nucleon elastic scattering. These results help oscillation experiments because they probe the importance of various correlations and final-state interaction effects within the nucleus, which have different effects on the visible energy in detectors.

Publisher's Note: Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer [Phys. Rev. Lett. 116, 071802 (2016)].

This corrects the article DOI: 10.1103/PhysRevLett.116.071802.

Measurement of Final-State Correlations in Neutrino Muon-Proton Mesonless Production on Hydrocarbon at ⟨E_{ν}⟩=3 GeV.

Final-state kinematic imbalances are measured in mesonless production of ν_{µ}+A→µ^{-}+p+X in the MINERvA tracker. Initial- and final-state nuclear effects are probed using the direction of the µ^{-}-p transverse momentum imbalance and the initial-state momentum of the struck neutron. Differential cross sections are compared to predictions based on current approaches to medium modeling. These models underpredict the cross section at intermediate intranuclear momentum transfers that generally exceed the Fermi momenta. As neutrino interaction models need to correctly incorporate the effect of the nucleus in order to predict neutrino energy resolution in oscillation experiments, this result points to a region of phase space where additional cross section strength is needed in current models, and demonstrates a new technique that would be suitable for use in fine-grained liquid argon detectors where the effect of the nucleus may be even larger.

Antineutrino Charged-Current Reactions on Hydrocarbon with Low Momentum Transfer.

We report on multinucleon effects in low momentum transfer (<0.8 GeV/c) antineutrino interactions on plastic (CH) scintillator. These data are from the 2010-2011 antineutrino phase of the MINERvA experiment at Fermilab. The hadronic energy spectrum of this inclusive sample is well described when a screening effect at a low energy transfer and a two-nucleon knockout process are added to a relativistic Fermi gas model of quasielastic, Δ resonance, and higher resonance processes. In this analysis, model elements introduced to describe previously published neutrino results have quantitatively similar benefits for this antineutrino sample. We present the results as a double-differential cross section to accelerate the investigation of alternate models for antineutrino scattering off nuclei.

Direct Measurement of Nuclear Dependence of Charged Current Quasielasticlike Neutrino Interactions Using MINERvA.

Charged-current ν_{µ} interactions on carbon, iron, and lead with a final state hadronic system of one or more protons with zero mesons are used to investigate the influence of the nuclear environment on quasielasticlike interactions. The transferred four-momentum squared to the target nucleus, Q^{2}, is reconstructed based on the kinematics of the leading proton, and differential cross sections versus Q^{2} and the cross-section ratios of iron, lead, and carbon to scintillator are measured for the first time in a single experiment. The measurements show a dependence on the atomic number. While the quasielasticlike scattering on carbon is compatible with predictions, the trends exhibited by scattering on iron and lead favor a prediction with intranuclear rescattering of hadrons accounted for by a conventional particle cascade treatment. These measurements help discriminate between different models of both initial state nucleons and final state interactions used in the neutrino oscillation experiments.

Measurement of Neutral-Current K

Neutral-current production of K^{+} by atmospheric neutrinos is a background in searches for the proton decay p→K^{+}ν[over ¯]. Reactions such as νp→νK^{+}Λ are indistinguishable from proton decays when the decay products of the Λ are below detection threshold. Events with K^{+} are identified in MINERvA by reconstructing the timing signature of a K^{+} decay at rest. A sample of 201 neutrino-induced neutral-current K^{+} events is used to measure differential cross sections with respect to the K^{+} kinetic energy, and the non-K^{+} hadronic visible energy. An excess of events at low hadronic visible energy is observed relative to the prediction of the neut event generator. Good agreement is observed with the cross section prediction of the genie generator. A search for photons from π^{0} decay, which would veto a neutral-current K^{+} event in a proton decay search, is performed, and a 2σ deficit of detached photons is observed relative to the genie prediction.

Comprehensive population screening in the Ashkenazi Jewish population for recurrent disease-causing variants.

The Ashkenazi Jewish (AJ) population has an increased risk for a variety of recessive diseases due to historical founder effects and genetic drift. For some, the disease-causing founder mutations have been identified and well-characterized, but for others, further study is necessary. The purpose of this study is to assess the carrier frequencies of 85 pathogenic variants causative of 29 recessive conditions in the AJ population. Up to 3000 AJ individuals were genotyped by Luminex MagPlex® -TAG™ bead array or Agena Bioscience™ MassARRAY assays. We identified seven conditions with carrier frequencies higher than 1 in 100, nine between 1 in 100 and 1 in 200, and four between 1 in 200 and 1 in 500. Variants in nine conditions had a detected carrier rate of less than 1 in 500 or were not identified in approximately 2000 AJ individuals. We assessed the combined AJ carrier frequency for 18 relatively prevalent diseases to be 1 in 6, and the risk of AJ individuals to be a carrier couple for one of these 18 diseases as 1 in 441. We note additional recessive genetic conditions should be considered for AJ carrier screening panels.

Evidence for Neutral-Current Diffractive π

The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current π^{0} production with a broad energy distribution peaking at 7 GeV and a total cross section of 0.26±0.02(stat.)±0.08(sys.)×10^{-39} cm^{2}. The angular distribution, electromagnetic shower energy, and spatial distribution of the energy depositions of the excess are consistent with expectations from neutrino neutral-current diffractive π^{0} production from hydrogen in the hydrocarbon target. These data comprise the first direct experimental observation and constraint for a reaction that poses an important background process in neutrino-oscillation experiments searching for ν_{µ} to ν_{e} oscillations.

Triheptanoin treatment in patients with pediatric cardiomyopathy associated with long chain-fatty acid oxidation disorders.

Long-chain fatty acid oxidation disorders (LC-FAOD) can cause cardiac hypertrophy and cardiomyopathy, often presenting in infancy, typically leading to death or heart transplant despite ongoing treatment. Previous data on triheptanoin treatment of cardiomyopathy in LC-FAOD suggested a clinical benefit on heart function during acute failure. An additional series of LC-FAOD patients with critical emergencies associated with cardiomyopathy was treated with triheptanoin under emergency treatment or compassionate use protocols. Case reports from 10 patients (8 infants) with moderate or severe cardiomyopathy associated with LC-FAOD are summarized. The majority of these patients were detected by newborn screening, with follow up confirmatory testing, including mutation analysis; all patients were managed with standard treatment, including medium chain triglyceride (MCT) oil. While on this regimen, they presented with acute heart failure requiring hospitalization and cardiac support (ventilation, ECMO, vasopressors) and, in some cases, resuscitation. The patients discontinued MCT oil and began treatment with triheptanoin, an investigational drug. Triheptanoin is expected to provide anaplerotic metabolites, to replace deficient TCA cycle intermediates and improve effective energy metabolism. Cardiac function was measured by echocardiography and ejection fraction (EF) was assessed. EF was moderately to severely impaired prior to triheptanoin treatment, ranging from 12-45%. Improvements in EF began between 2 and 21days following initiation of triheptanoin, and peaked at 33-71%, with 9 of 10 patients achieving EF in the normal range. Continued treatment was associated with longer-term stabilization of clinical signs of cardiomyopathy. The most common adverse event observed was gastrointestinal distress. Of the 10 patients, 7 have continued on treatment, 1 elected to discontinue due to tolerability issues, and 2 patients died from other causes. Two of the case histories illustrate that cardiomyopathy may also develop later in childhood and/or persist into adulthood. Overall, the presented cases suggest a therapeutic effect of triheptanoin in the management of acute cardiomyopathy associated with LC-FAOD.

Evidence of Coherent K

Neutrino-induced charged-current coherent kaon production ν_{µ}A→µ^{-}K^{+}A is a rare, inelastic electroweak process that brings a K^{+} on shell and leaves the target nucleus intact in its ground state. This process is significantly lower in rate than the neutrino-induced charged-current coherent pion production because of Cabibbo suppression and a kinematic suppression due to the larger kaon mass. We search for such events in the scintillator tracker of MINERvA by observing the final state K^{+}, µ^{-}, and no other detector activity, and by using the kinematics of the final state particles to reconstruct the small momentum transfer to the nucleus, which is a model-independent characteristic of coherent scattering. We find the first experimental evidence for the process at 3σ significance.

Measurement of Electron Neutrino Quasielastic and Quasielasticlike Scattering on Hydrocarbon at ⟨E_{ν}⟩=3.6 GeV.

The first direct measurement of electron neutrino quasielastic and quasielasticlike scattering on hydrocarbon in the few-GeV region of incident neutrino energy has been carried out using the MINERvA detector in the NuMI beam at Fermilab. The flux-integrated differential cross sections in the electron production angle, electron energy, and Q^{2} are presented. The ratio of the quasielastic, flux-integrated differential cross section in Q^{2} for ν_{e} with that of similarly selected ν_{µ}-induced events from the same exposure is used to probe assumptions that underpin conventional treatments of charged-current ν_{e} interactions used by long-baseline neutrino oscillation experiments. The data are found to be consistent with lepton universality and are well described by the predictions of the neutrino event generator GENIE.

Identification of Nuclear Effects in Neutrino-Carbon Interactions at Low Three-Momentum Transfer.

Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current ν_{µ} interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

Glutamine and hyperammonemic crises in patients with urea cycle disorders.

UNLABELLED: Blood ammonia and glutamine levels are used as biomarkers of control in patients with urea cycle disorders (UCDs). This study was undertaken to evaluate glutamine variability and utility as a predictor of hyperammonemic crises (HACs) in UCD patients. METHODS: The relationships between glutamine and ammonia levels and the incidence and timing of HACs were evaluated in over 100 adult and pediatric UCD patients who participated in clinical trials of glycerol phenylbutyrate. RESULTS: The median (range) intra-subject 24-hour coefficient of variation for glutamine was 15% (8-29%) as compared with 56% (28%-154%) for ammonia, and the correlation coefficient between glutamine and concurrent ammonia levels varied from 0.17 to 0.29. Patients with baseline (fasting) glutamine values >900 µmol/L had higher baseline ammonia levels (mean [SD]: 39.6 [26.2]µmol/L) than patients with baseline glutamine ≤ 900 µmol/L (26.6 [18.0]µmol/L). Glutamine values >900 µmol/L during the study were associated with an approximately 2-fold higher HAC risk (odds ratio [OR]=1.98; p=0.173). However, glutamine lost predictive significance (OR=1.47; p=0.439) when concomitant ammonia was taken into account, whereas the predictive value of baseline ammonia ≥ 1.0 upper limit of normal (ULN) was highly statistically significant (OR=4.96; p=0.013). There was no significant effect of glutamine >900 µmol/L on time to first HAC crisis (hazard ratio [HR]=1.14; p=0.813), but there was a significant effect of baseline ammonia ≥ 1.0 ULN (HR=4.62; p=0.0011). CONCLUSIONS: The findings in this UCD population suggest that glutamine is a weaker predictor of HACs than ammonia and that the utility of the predictive value of glutamine will need to take into account concurrent ammonia levels.

Urinary phenylacetylglutamine (U-PAGN) concentration as biomarker for adherence in patients with urea cycle disorders (UCD) treated with glycerol phenylbutyrate.

Urinary phenylacetylglutamine (U-PAGN) concentrations in spot urine samples were analyzed as a dosing biomarker during glycerol phenylbutyrate (GPB) dosing in 68 healthy adults and 66 adult and pediatric patients with urea cycle disorders who participated in GPB clinical trials. Age- and body surface area (BSA)-specific 25th percentile cutoff points for spot U-PAGN concentrations (<~9000 µg/mL for < 2 years old patients, < 7000 µg/mL for > 2 years with BSA ≤ 1.3 m2, and <~5000 µg/mL for > 2 years of age with BSA > 1.3 m2) were determined as an approach to identify patients for whom increased dosing and/or adherence to prescribed dosing should be assessed.