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1.
Phys Rev Lett ; 129(20): 201801, 2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36461983

ABSTRACT

This Letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone and in combination with MicroBooNE electron-neutrino data. The best-fit parameters of the combined fit with the exclusive charged-current quasielastic analysis (inclusive analysis) are Δm^{2}=0.209 eV^{2}(0.033 eV^{2}), |U_{e4}|^{2}=0.016(0.500), |U_{µ4}|^{2}=0.500(0.500), and sin^{2}(2θ_{µe})=0.0316(1.0). Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a Δχ^{2}/d.o.f.=24.7/3(17.3/3), a 4.3σ(3.4σ) preference assuming the asymptotic approximation given by Wilks's theorem.

2.
Phys Rev Lett ; 121(22): 221801, 2018 Nov 30.
Article in English | MEDLINE | ID: mdl-30547637

ABSTRACT

The MiniBooNE experiment at Fermilab reports results from an analysis of ν_{e} appearance data from 12.84×10^{20} protons on target in neutrino mode, an increase of approximately a factor of 2 over previously reported results. A ν_{e} charged-current quasielastic event excess of 381.2±85.2 events (4.5σ) is observed in the energy range 200

3.
Phys Rev Lett ; 120(14): 141802, 2018 Apr 06.
Article in English | MEDLINE | ID: mdl-29694148

ABSTRACT

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^{+}→µ^{+}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.

4.
Phys Rev Lett ; 110(16): 161801, 2013 Apr 19.
Article in English | MEDLINE | ID: mdl-23679593

ABSTRACT

The MiniBooNE experiment at Fermilab reports results from an analysis of ν[over ¯](e) appearance data from 11.27×10(20) protons on target in the antineutrino mode, an increase of approximately a factor of 2 over the previously reported results. An event excess of 78.4±28.5 events (2.8σ) is observed in the energy range 200

5.
Phys Rev Lett ; 103(6): 061802, 2009 Aug 07.
Article in English | MEDLINE | ID: mdl-19792551

ABSTRACT

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.

6.
Phys Rev Lett ; 103(8): 081801, 2009 Aug 21.
Article in English | MEDLINE | ID: mdl-19792715

ABSTRACT

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

7.
Phys Rev Lett ; 102(21): 211801, 2009 May 29.
Article in English | MEDLINE | ID: mdl-19519094

ABSTRACT

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.

8.
Phys Rev Lett ; 102(10): 101802, 2009 Mar 13.
Article in English | MEDLINE | ID: mdl-19392103

ABSTRACT

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.

9.
Phys Rev Lett ; 100(3): 032301, 2008 Jan 25.
Article in English | MEDLINE | ID: mdl-18232974

ABSTRACT

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.

10.
Phys Rev Lett ; 98(23): 231801, 2007 Jun 08.
Article in English | MEDLINE | ID: mdl-17677898

ABSTRACT

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.

12.
J Am Diet Assoc ; 91(6): 691-4, 1991 Jun.
Article in English | MEDLINE | ID: mdl-2040784

ABSTRACT

The purpose of this study was to develop an inventory control system achievement test that measures cognitive achievement of students in a foodservice management information systems course. We developed a table of specifications for inventory control systems that included the following content areas: receiving, storing, issuing, inventory control, inventory valuation, and inventory control computer systems. We composed 114 test items in a multiple-choice format on the basis of the table of specifications. A sample of 105 students responded to the test; each had previously received 3 hours of instruction on inventory control systems in a foodservice management information systems course. The 50 best items, judged on the basis of item-analysis data and adherence to the table of specification, were selected for the final form of the inventory control system achievement test. The 50-item test was reliable as indicated by a Kuder-Richardson 20 value of .84. The test may be used to evaluate individual student's achievement, to evaluate the effectiveness of instruction, and to compare achievement of different groups.


Subject(s)
Dietetics/education , Educational Measurement , Food Services , Information Systems , Humans
13.
J Nutr ; 119(2): 215-20, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2918394

ABSTRACT

The concentration of selenium (Se) in milk samples obtained from 26 lacto-ovo-vegetarian (vegetarian) women was significantly greater (22.2 +/- 0.8 ng/ml) than from 12 nonvegetarian women (16.8 +/- 1.3). Mean GSH-Px activity (EC 1.11.1.9) in milk from vegetarians was 146% of that in milk from nonvegetarians. A significant correlation between GSH-Px activity and Se concentration was observed (r = 0.76). Likewise a significant correlation was observed between milk linoleic acid content and GSH-Px activity (r = 0.68). In undialyzed samples from vegetarian women, most of the increased content of Se was found in fractions containing proteins of 100 kdaltons (kD) or more. The high glutathione peroxidase activity in milk from vegetarians was associated with selenoproteins in the 90 to 100 kD range. A distinct 40 kD Se peak was also detected in milk from vegetarians. There was no difference in Se intake between the two groups of women. Therefore, although data from the present study show that both the quantity and distribution of Se in human milk can be modified by the maternal diet, the increased Se content and GSH-Px activity in milk from vegetarians cannot be explained by an increased Se intake.


Subject(s)
Diet, Vegetarian , Glutathione Peroxidase/analysis , Milk, Human/analysis , Selenium/analysis , Adult , Chromatography/methods , Female , Humans , Milk, Human/enzymology
14.
J Am Diet Assoc ; 85(6): 678-85, 1985 Jun.
Article in English | MEDLINE | ID: mdl-3998337

ABSTRACT

Data on food choices and nutrient intake were obtained from 60 lactating women, including 29 vegetarians. The most common changes in consumption patterns during pregnancy were increased intake of high-protein foods, especially milk products, and decreased intake of coffee, tea, and alcohol. The changes were partially based on food cravings and/or aversions. In addition to high-protein foods, some of the women craved fruits and sweets. Items most commonly eliciting aversive reactions were vegetables, strong-smelling and strong-tasting combination dishes, and greasy foods. Aversions to coffee, tea, and alcohol were almost as frequent as those to greasy foods. Nutrient intake during lactation was measured using 24-hour recalls and 2-day diet records that also considered dietary supplements. A total of 332 intake records were evaluated relative to the RDAs for lactating women. Mean energy intake was 2,200 kcal (88% of the recommendation), and mean protein intake was 86 gm (134% of the RDA). Mean nutrient intakes from diet alone ranged from 89% of the RDA for iron to 154% for vitamin A; mean intakes from diet plus supplements ranged from 133% of the RDA for calcium to 581% of the RDA for thiamin. Dietary supplementation provided a substantial part of the intake of some nutrients; for most women, however, the RDAs were met by diet alone.


Subject(s)
Diet, Vegetarian , Diet , Food Preferences , Lactation , Adult , Diet Surveys , Energy Intake , Female , Humans , Mental Recall , Nutritional Requirements , Pregnancy
15.
J Nutr ; 115(6): 772-81, 1985 Jun.
Article in English | MEDLINE | ID: mdl-3998870

ABSTRACT

Changes in concentrations of minerals, trace elements, protein, lactose and total lipids during 20 mo of lactation and correlations between levels of these milk constituents were studied in a carefully defined set of 222 milk samples collected from 52 women, one-half of whom were vegetarians. Milk samples from vegetarians and those from nonvegetarians contained similar levels of iron, copper, zinc, sodium, potassium, calcium, magnesium, lactose and fat. Following a brief but sharp initial decrease, levels of protein and iron did not change significantly between mo 2 and 20 of lactation. Levels of zinc, copper, sodium and potassium declined for the first 6 mo of lactation. Levels of lipid, sodium and zinc increased during later months of lactation while that of calcium decreased. Levels of lactose, copper, potassium and magnesium remained unchanged during mo 7-20. Stepwise multiple regression analysis showed positive correlations between levels of three pairs of inorganic constituents during the first 6 mo of lactation: copper and zinc, copper and potassium, and potassium and calcium. During the subsequent 14 mo of lactation, potassium was correlated with copper. The level of iron was positively correlated with that of lipid, while that of calcium was negatively correlated with that of lipid. These relationships, and others reported in the paper, are discussed in relation to current hypotheses of the mechanism of milk secretion and the binding of inorganic to organic milk constituents.


Subject(s)
Diet, Vegetarian , Milk, Human/analysis , Minerals/analysis , Trace Elements/analysis , Adult , Diet , Female , Humans , Lactose/analysis , Lipids/analysis , Longitudinal Studies , Metals/analysis , Milk Proteins/analysis
16.
Am J Clin Nutr ; 41(4): 787-800, 1985 Apr.
Article in English | MEDLINE | ID: mdl-3984932

ABSTRACT

Milk from vegetarians contained a lower proportion of fatty acids derived from animal fat and a higher proportion of polyunsaturated fatty acids derived from dietary vegetable fat. No significant differences were observed between dietary groups in percent fat in the milk or in proportions of fatty acids synthesized de novo in the mammary gland. Among women consuming less than 35 g animal fat per day, percent milk fat was significantly correlated with animal fat intake. Among women consuming greater than 35 g animal fat, percent fat in milk was positively correlated with percent of C10:0, C12:0, and C18:3 and negatively correlated with percent of C16:0 and C18:0 in the milk fat. These findings suggest that there is a maximum amount of C16:0 and C18:0 that can be taken up from the blood and subsequently secreted into the milk.


Subject(s)
Diet, Vegetarian , Dietary Fats/analysis , Fatty Acids/analysis , Milk, Human/analysis , Adult , Chemical Phenomena , Chemistry , Diet , Fatty Acids, Unsaturated/analysis , Female , Humans , Longitudinal Studies
17.
J Pediatr Gastroenterol Nutr ; 3(5): 713-20, 1984 Nov.
Article in English | MEDLINE | ID: mdl-6502372

ABSTRACT

Breast milk composition of 119 samples collected by 46 women during months 7-20 of lactation was compared with composition of 101 samples collected at 4-6 months. Breast milk intake of 10 infants was determined by test-weighing for 1 or more months during months 7-16 of lactation. Longitudinal decreases in milk concentrations of zinc, copper, and potassium, previously documented for the first 6 months, continued into the second 6 months, while protein, iron, and sodium concentrations showed no further decline. Lactose, fat, calcium, and magnesium concentrations were similar to those in earlier stages of lactation. Weaning was associated with significant changes in milk composition: When milk volume fell below 300 ml/day, there was an increase in protein and sodium and a decrease in lactose, calcium, and zinc. Breast milk intake of infants not supplemented with cow's milk or formula averaged 875 ml/day (93% of total energy intake) at 7 months and 550 ml/day (50% of total energy intake) at 11-16 months. Total energy intake increased from 610 to 735 kcal/day, but energy intake per kilogram remained constant at a relatively low 70-79 kcal/kg/day. Our results suggest the need for further studies of nutrient intake and requirements of breast-fed infants during late lactation.


Subject(s)
Lactation , Milk, Human/analysis , Adult , Energy Intake , Energy Metabolism , Female , Humans , Infant , Infant Food , Male , Milk, Human/metabolism , Milk, Human/physiology , Nutritive Value , Pregnancy
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