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1.
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.

2.
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}.

3.
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}.

4.
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.

5.
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.

6.
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.

7.
Phys Rev Lett ; 108(19): 191801, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-23003026

RESUMO

We report an improved measurement of ν(µ) disappearance over a distance of 735 km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a ν(µ)-enhanced configuration. From a total exposure of 2.95×10(20) protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of Δm2=[2.62(-0.28)(+0.31)(stat)±0.09(syst)]×10(-3) eV2 and constrain the ν(µ) mixing angle sin2(2θ)>0.75 (90% C.L.). These values are in agreement with Δm2 and sin2(2θ) measured for ν(µ), removing the tension reported in [P. Adamson et al. (MINOS), Phys. Rev. Lett. 107, 021801 (2011).].

8.
Nat Microbiol ; 7(6): 810-819, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35618773

RESUMO

Animals and microorganisms often establish close ecological relationships. However, much of our knowledge about animal microbiomes comes from two deeply studied groups: vertebrates and arthropods. To understand interactions on a broader scale of diversity, we characterized the bacterial microbiomes of close to 1,000 microscopic marine invertebrates from 21 phyla, spanning most of the remaining tree of metazoans. Samples were collected from five temperate and tropical locations covering three marine habitats (sediment, water column and intertidal macroalgae) and bacterial microbiomes were characterized using 16S ribosomal RNA gene sequencing. Our data show that, despite their size, these animals harbour bacterial communities that differ from those in the surrounding environment. Distantly related but coexisting invertebrates tend to share many of the same bacteria, suggesting that guilds of microorganisms preferentially associated with animals, but not tied to any specific host lineage, are the main drivers of the ecological relationship. Host identity is a minor factor shaping these microbiomes, which do not show the same correlation with host phylogeny, or 'phylosymbiosis', observed in many large animals. Hence, the current debate on the varying strength of phylosymbiosis within selected lineages should be reframed to account for the possibility that such a pattern might be the exception rather than the rule.


Assuntos
Microbiota , Animais , Bactérias/genética , Microbiota/genética , Filogenia , Vertebrados
9.
Phys Rev Lett ; 106(18): 181801, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21635083

RESUMO

Measurements of neutrino oscillations using the disappearance of muon neutrinos from the Fermilab NuMI neutrino beam as observed by the two MINOS detectors are reported. New analysis methods have been applied to an enlarged data sample from an exposure of 7.25×10(20) protons on target. A fit to neutrino oscillations yields values of |Δm(2)|=(2.32(-0.08)(+0.12))×10(-3) eV(2) for the atmospheric mass splitting and sin(2)(2θ)>0.90 (90% C.L.) for the mixing angle. Pure neutrino decay and quantum decoherence hypotheses are excluded at 7 and 9 standard deviations, respectively.

10.
Phys Rev Lett ; 107(1): 011802, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21797535

RESUMO

Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on the observation of neutral-current neutrino interactions, from an exposure to the NuMI neutrino beam of 7.07×10(20) protons on target. A total of 802 neutral-current event candidates is observed in the Far Detector, compared to an expected number of 754 ± 28(stat) ± 37(syst) for oscillations among three active flavors. The fraction f(s) of disappearing ν(µ) that may transition to ν(s) is found to be less than 22% at the 90% C.L.

11.
Phys Rev Lett ; 107(2): 021801, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21797594

RESUMO

This Letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ν(µ) production, accumulating an exposure of 1.71 × 10²° protons on target. In the Far Detector, 97 charged current ν(µ) events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3σ. The best fit to oscillation yields |Δm²| = [3.36(-0.40)(+0.46)(stat) ± 0.06(syst)] × 10⁻³ eV², sin²(2θ) = 0.86(-0.12)(+0.11)(stat) ± 0.01(syst). The MINOS ν(µ) and ν(µ) measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

12.
Phys Rev Lett ; 107(18): 181802, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22107623

RESUMO

We report the results of a search for ν(e) appearance in a ν(µ) beam in the MINOS long-baseline neutrino experiment. With an improved analysis and an increased exposure of 8.2 × 10(20) protons on the NuMI target at Fermilab, we find that 2 sin(2) (θ(23))sin(2)(2θ(13))<0.12(0.20) at 90% confidence level for δ = 0 and the normal (inverted) neutrino mass hierarchy, with a best-fit of 2sin(2) (θ(23))sin(2)(2θ(13)) = 0.041(-0.031)(+0.047) (0.079(-0.053) (+0.071)). The θ(13) = 0 hypothesis is disfavored by the MINOS data at the 89% confidence level.

13.
Phys Rev Lett ; 105(15): 151601, 2010 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-21230890

RESUMO

We searched for a sidereal modulation in the MINOS far detector neutrino rate. Such a signal would be a consequence of Lorentz and CPT violation as described by the standard-model extension framework. It also would be the first detection of a perturbative effect to conventional neutrino mass oscillations. We found no evidence for this sidereal signature, and the upper limits placed on the magnitudes of the Lorentz and CPT violating coefficients describing the theory are an improvement by factors of 20-510 over the current best limits found by using the MINOS near detector.

14.
Phys Rev Lett ; 103(26): 261802, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-20366304

RESUMO

This Letter reports on a search for nu(mu) --> nu(e) transitions by the MINOS experiment based on a 3.14x10(20) protons-on-target exposure in the Fermilab NuMI beam. We observe 35 events in the Far Detector with a background of 27+/-5(stat)+/-2(syst) events predicted by the measurements in the Near Detector. If interpreted in terms of nu(mu) --> nu(e) oscillations, this 1.5sigma excess of events is consistent with sin2(2theta(13)) comparable to the CHOOZ limit when |Delta m2|=2.43x10(-3) eV2 and sin2(2theta(23))=1.0 are assumed.

15.
Mol Cell Endocrinol ; 26(3): 341-51, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-6176479

RESUMO

RNA transcription in the silk glands of the wax moth, Galleria mellonella, decreases during cocoon spinning and particularly later in pharate pupae, when the glands begin to degenerate. Application of juvenile hormone to insects at those developmental stages enhances synthesis of polyadenylated RNA 4-6 times and to lesser extent synthesis of total RNA. The newly formed poly(A)RNA appears identical with that from the normally fully functioning and silk-producing glands: it contains the same predominant poly(A)RNA class and is equally readily translated in the wheat-germ system. The results indicate that the hormone restores the function of silk glands at the transcriptional level.


Assuntos
Glândulas Exócrinas/metabolismo , Hormônios Juvenis/farmacologia , Lepidópteros/fisiologia , Mariposas/fisiologia , RNA/metabolismo , Animais , Glândulas Exócrinas/efeitos dos fármacos , Metamorfose Biológica , Poli A/metabolismo , Biossíntese de Proteínas , RNA Mensageiro , Transcrição Gênica
16.
Insect Biochem Mol Biol ; 24(2): 133-44, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8111425

RESUMO

We cloned and sequenced a composite cDNA corresponding to the 2.6 kb last instar-specific, juvenile hormone-suppressible Lhp82 mRNA from Galleria mellonella. The identity of the cDNA was confirmed by N-terminal amino acid sequencing of the purified Lhp82 subunit. In addition, we sequenced all coding regions and most of the intronic DNA as well as 1300 nucleotides of 5' flanking DNA from the Lhp82 gene. The eight exons of the Lhp82 gene specify a pre-protein of 706 residues, including the signal peptide of 18 amino acids. The deduced amino acid sequence of Lhp82 contains four potential N-glycosylation sites, and the calculated isoelectric point and molecular weight of secreted Lhp82 are pI = 6.43 and 79.9 kDa, respectively. Inspection of the 5' flanking and intronic regions of Lhp82 DNA revealed a 301 nucleotide cassette in intron 6 that appears to be a recently inserted repetitive element. We also performed Northern blot and nuclear run-off transcription experiments in order to determine the basis for Lhp82 gene inactivity after day 2 of the pupal stage. The results of these studies indicate that Lhp82 transcription is permanently shut off by the ecdysteroid pulse which occurs in the absence of juvenile hormone beginning 24 h post-pupation.


Assuntos
Proteínas de Drosophila , Genes de Insetos , Hormônios de Inseto/genética , Proteínas de Insetos , Mariposas/genética , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Sequência de Bases , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/genética , Éxons , Regulação da Expressão Gênica , Genes de Insetos/efeitos dos fármacos , Hormônios de Inseto/química , Íntrons , Hormônios Juvenis/farmacologia , Dados de Sequência Molecular , Peso Molecular , Mariposas/crescimento & desenvolvimento , Conformação Proteica , Homologia de Sequência de Aminoácidos
17.
Acta Biochim Pol ; 38(1): 53-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1796707

RESUMO

Synthesis of the low molecular mass silk proteins of 24 and 30 kDa in the last larval instar of Galleria mellonella starts between 24 and 48 h; synthesis of the former protein significantly preceding that of the latter. Posterior silk glands (PSG) from day-1 last instar larvae are transiently sensitive in vitro to exogenous 20-hydroxyecdysone (20-HE), which stimulates transcription of the 24 kDa protein gene and induces transcription of the gene for the 30 kDa protein. The glands from the day -3 last instar larvae are insensitive to this hormone. The brain extract acts directly on RNA synthesis in silk gland in vitro at the concentration of 0.1 brain equivalent per gland. This factor is protease sensitive and thermostable.


Assuntos
Ecdisterona/farmacologia , Proteínas de Insetos , Mariposas/metabolismo , Biossíntese de Proteínas , Animais , Encéfalo/fisiologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Peso Molecular , Mariposas/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Proteínas/efeitos dos fármacos , Proteínas/genética , Seda , Transcrição Gênica
18.
Acta Biochim Pol ; 43(4): 639-44, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9104500

RESUMO

In developing Galleria mellonella larvae (reared at 30 degrees C) three proteins of 74, 76 and 81/82 kDa were identified. They represent a group of storage proteins (LHP proteins). In Galleria larvae, the development of which is arrested by low temperature (18 degrees C), accumulation of the 74, 76 and 81/82 kDa proteins was detected in the hemolymph. The synthesis of 74 kDa and 76 kDa proteins started after 24 h, and that of about 80 kDa after 96 h following the transfer of larvae from 30 degrees C to 18 degrees C. 20-Hydroxyecdysone inhibited synthesis of the 74 and 76 kDa proteins in larvae exposed to low temperature. The arrest of development of Galleria larvae is associated with the synthesis and accumulation of storage proteins, and ecdysteroids are involved in these processes.


Assuntos
Proteínas de Insetos/biossíntese , Animais , Temperatura Baixa , Eletroforese em Gel de Poliacrilamida , Hemolinfa , Lepidópteros/embriologia
19.
Comp Biochem Physiol B Biochem Mol Biol ; 110(4): 671-81, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7749619

RESUMO

At least three silk genes are specifically expressed in the posterior, and five other genes in middle, silk glands. The products of genes active in PSG include fibroin, L-chain fibroin and P25 protein. PSG genes as well as the Ser-1 gene, differing in structure, exhibit a striking degree of homology of their 5' flanking sequences. This suggests the presence of common regulatory mechanisms. The expression of silk protein genes is probably controlled by tissue-specific and general transcriptional factors. Hormones seem to participate in the regulation of expression of silk protein genes.


Assuntos
Bombyx/genética , Regulação da Expressão Gênica/fisiologia , Genes de Insetos , Hormônios de Inseto/fisiologia , Lepidópteros/genética , Proteínas/genética , Animais , Sequência de Bases , Meio Ambiente , Dados de Sequência Molecular
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