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1.
Phys Rev Lett ; 120(14): 141802, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29694148

RESUMO

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.

2.
Phys Rev Lett ; 113(26): 261801, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615307

RESUMO

We report on the first cross section measurements for charged current coherent pion production by neutrinos and antineutrinos on argon. These measurements are performed using the ArgoNeuT detector exposed to the NuMI beam at Fermilab. The cross sections are measured to be 2.6(-1.0)(+1.2)(stat)(-0.4)(+0.3)(syst)×10(-38) cm(2)/Ar for neutrinos at a mean energy of 9.6 GeV and 5.5(-2.1)(+2.6)(stat)(-0.7)(+0.6)(syst)×10(-39) cm(2)/Ar for antineutrinos at a mean energy of 3.6 GeV.

3.
Phys Rev Lett ; 110(16): 161801, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23679593

RESUMO

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

4.
Phys Rev Lett ; 108(16): 161802, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22680709

RESUMO

The ArgoNeuT Collaboration presents the first measurements of inclusive muon neutrino charged current differential cross sections on argon. Obtained in the NuMI neutrino beam line at Fermilab, the flux-integrated results are reported in terms of outgoing muon angle and momentum. The data are consistent with the Monte Carlo expectation across the full range of kinematics sampled, 0°<θ(µ)<36° and 0

5.
Phys Rev Lett ; 99(19): 192001, 2007 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-18233069

RESUMO

We present a new measurement of the difference between the nucleon strange and antistrange quark distributions from dimuon events recorded by the NuTeV experiment at Fermilab. This analysis is the first to use a complete next to leading order QCD description of charm production from neutrino scattering. Dimuon events in neutrino deep inelastic scattering allow direct and independent study of the strange and antistrange content of the nucleon. We find a positive strange asymmetry with a significance of 1.6sigma. We also report a new measurement of the charm mass.

6.
Dtsch Med Wochenschr ; 128(25-26): 1399-402, 2003 Jun 20.
Artigo em Alemão | MEDLINE | ID: mdl-12813674

RESUMO

HISTORY AND CLINICAL FINDINGS: A 58-year-old patient suffered from rapidly progressing renal insufficiency and 11 kg weight-loss three months after adjuvant treatment of a carcinoma of the lower bowel (G 2 T 3 N 1 M 0 ) with mitomycine C. At the point of hospitalisation the patient was anuric while suffering from pulmonary oedema, hemolytic anemia and thrombocytopenia. INVESTIGATIONS: Computed tomography and bronchial endoscopy showed pulmonary haemorrhage. Recurrence of carcinoma or metastases were excluded. Renal biopsy revealed mesangiolysis and concentric intimaproliferation (onion skinning). Beside haemolytic anaemia and fragmentocytes toxic damage of the bone marrow was found. TREATMENT AND COURSE: After one week treatment in the intensive care unit because of respiratory insufficiency recovery was observed under plasma separation and high dose corticosteroid therapy. Disease activity involved renal failure, bone marrow insufficiency, microangiopathic anaemia thrombopenia and pulmonary haemorrhage. CONCLUSION: Lung involvement in the course of haemolytic uremic syndrome is rare and carries a high lethality. The case illustrates the need of detailed diagnostic for correct treatment of haemolytic uremic syndrome. If chemotherapy is required in patients with pre-existing or intercurrent renal failure dose adaptation is necessary to avoid dose-dependent toxicity of mitomycine C.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Síndrome Hemolítico-Urêmica/induzido quimicamente , Mitomicina/efeitos adversos , Antibióticos Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante , Síndrome Hemolítico-Urêmica/complicações , Síndrome Hemolítico-Urêmica/patologia , Hemorragia/diagnóstico , Hemorragia/etiologia , Humanos , Pneumopatias/diagnóstico , Pneumopatias/etiologia , Masculino , Pessoa de Meia-Idade , Mitomicina/uso terapêutico , Prognóstico , Neoplasias do Colo Sigmoide/tratamento farmacológico , Neoplasias do Colo Sigmoide/cirurgia
7.
Phys Rev Lett ; 89(1): 011804, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12097033

RESUMO

Limits on nu(mu)-->nu(e) and nu(mu)-->nu(e) oscillations are extracted using the NuTeV detector with sign-selected nu(mu) and nu(mu) beams. In nu(mu) mode, for the case of sin(2)2alpha = 1, Delta(m)(2)>2.6 eV(2) is excluded, and for Delta(m)(2)>>1000 eV(2), sin(2)2alpha>1.1 x 10(-3). The NuTeV data exclude the high Delta(m)(2) end of nu(mu)-->nu(e) oscillation parameters favored by the LSND experiment without the need to assume that the oscillation parameters for nu and nu are the same. We present the most stringent experimental limits for nu(mu)(nu(mu))-->nu(e)(nu(e)) oscillations in the large Delta(m)(2) region.

8.
Phys Rev Lett ; 88(9): 091802, 2002 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-11863995

RESUMO

The NuTeV Collaboration has extracted the electroweak parameter sin(2)theta(W) from the measurement of the ratios of neutral current to charged current nu and (-)nu cross sections. Our value, sin(2)theta((on-shell))(W) = 0.2277 +/- 0.0013(stat) +/- 0.0009(syst), is 3 standard deviations above the standard model prediction. We also present a model independent analysis of the same data in terms of neutral-current quark couplings.

9.
Phys Rev Lett ; 87(25): 251802, 2001 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-11736561

RESUMO

We report on the extraction of R = sigma(L)/sigma(T) from CCFR nu(mu)-Fe and nu(mu)-Fe differential cross sections. The CCFR differential cross sections do not show the deviations from the QCD expectations that are seen in the CDHSW data at very low and very high x. R as measured in nu(mu) scattering is in agreement with R as measured in muon and electron scattering. All data on R for Q(2)>1 GeV(2) are in agreement with a NNLO QCD calculation which uses NNLO parton distribution functions and includes target mass effects. We report on the first measurements of R in the low x and Q(2)<1 GeV(2) region (where an anomalous large rise in R for nuclear targets has been observed by the HERMES Collaboration).

10.
Phys Rev Lett ; 87(7): 071803, 2001 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-11497881

RESUMO

The NuTeV experiment at Fermilab has used a sign-selected neutrino beam to perform a search for the lepton number violating process nu(mu)e(-)-->mu(-)nu(e), and to measure the cross section of the standard model inverse muon decay process nu(mu)e(-)-->mu(-)nu(e). NuTeV measures the inverse muon decay asymptotic cross-section slope sigma/E to be (13.8 +/- 1.2 +/- 1.4) x 10(-42) cm(2)/GeV. The experiment also observes no evidence for lepton number violation and places one of the most restrictive limits on the cross-section ratio sigma(nu(mu)e(-)-->mu(-)nu(e))/sigma(nu(mu)e(-)-->mu(-)nu(e)) < or = 1.7% at 90% C.L. for V-A couplings and < or = 0.6% for scalar couplings.

11.
Infect Immun ; 69(9): 5538-45, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11500427

RESUMO

The DegP protease, a multifunctional chaperone and protease, has been shown to be essential for virulence in gram-negative pathogens such as Salmonella enterica serovar Typhimurium, Brucella abortus, Yersinia enterocolitica, and Pseudomonas aeruginosa. The function of DegP in pathogenesis appears to be the degradation of damaged proteins that accumulate as a result of the initial host response to infection, which includes the release of reactive oxygen intermediates. Additionally, the DegP protease plays a major role in monitoring and maintaining the Escherichia coli periplasm and influences E. coli pilus biogenesis. We report here the identification of highly homologous enzymes in Streptococcus pyogenes, Streptococcus gordonii, Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis. Moreover, the phenotype of an insertionally inactivated degP allele in S. pyogenes is similar to that reported for E. coli, with temperature sensitivity for growth and enhanced sensitivity to reactive oxygen intermediates. Virulence studies in a mouse model of streptococcal infection indicate that a functional DegP protease is required for full virulence. These results suggest DegP as an attractive broad-spectrum target for future anti-infective drug development.


Assuntos
Bactérias Gram-Positivas/enzimologia , Bactérias Gram-Positivas/patogenicidade , Proteínas de Choque Térmico , Temperatura Alta , Estresse Oxidativo , Proteínas Periplásmicas , Serina Endopeptidases/genética , Streptococcus pyogenes/patogenicidade , Sequência de Aminoácidos , Animais , Modelos Animais de Doenças , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/fisiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Camundongos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/enzimologia , Streptococcus pyogenes/genética , Virulência
12.
Phys Rev Lett ; 87(4): 041801, 2001 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-11461608

RESUMO

A search for long-lived neutral particles ( N0's) with masses above 2.2 GeV/c(2) that decay into at least one muon has been performed using an instrumented decay channel at the NuTeV experiment at Fermilab. Data were examined for particles decaying into the final states mumu, mu(e), and mu(pi). Three mumu events were observed over an expected standard model background of 0.069+/-0.010 events; no events were observed in the other modes.

13.
Phys Rev Lett ; 86(24): 5430-3, 2001 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-11415268

RESUMO

A new structure function analysis of CCFR deep inelastic nu-N and nu-N scattering data is presented for previously unexplored kinematic regions down to Bjorken x = 0.0045 and Q(2) = 0.3 GeV(2). Comparisons to charged lepton scattering data from NMC and E665 experiments are made and the behavior of the structure function F(2)(nu)2 is studied in the limit Q(2)-->0.

14.
Appl Microbiol Biotechnol ; 55(2): 192-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11330713

RESUMO

A new intragenic chromosomal integration site within the lacG gene of the lac operon has been identified in Streptococcus gordonii for use in the expression of foreign genes. Introduction of a portion of the Streptococcus pyogenes emm6 gene into the lacG locus resulted in the lactose-inducible surface expression of the S. pyogenes M6 protein. This result demonstrates the ability to modulate the in vitro or in vivo expression of a foreign gene in a S. gordonii recombinant using a biosynthetic metabolite.


Assuntos
Antígenos de Bactérias , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Transporte/genética , Expressão Gênica , Glicosídeo Hidrolases , Óperon Lac , Streptococcus/genética , Transformação Bacteriana , beta-Galactosidase/genética , Proteínas da Membrana Bacteriana Externa/biossíntese , Proteínas de Transporte/biossíntese , Inativação Gênica , Genes Bacterianos , Mutagênese Insercional , Regiões Promotoras Genéticas , Proteínas Recombinantes/biossíntese , Streptococcus pyogenes/genética
15.
Phys Rev Lett ; 86(13): 2742-5, 2001 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-11290028

RESUMO

We report on the extraction of the structure functions F2 and DeltaxF(3) = xF(nu)(3)-xF(nu;)(3) from CCFR nu(mu)-Fe and nu;(mu)-Fe differential cross sections. The extraction is performed in a physics model-independent (PMI) way. This first measurement of DeltaxF(3), which is useful in testing models of heavy charm production, is higher than current theoretical predictions. The ratio of the F2 (PMI) values measured in nu(mu) and mu scattering is in agreement (within 5%) with the predictions of next-to-leading-order parton distribution functions using massive charm production schemes, thus resolving the long-standing discrepancy between the two sets of data.

16.
Infect Immun ; 69(1): 75-80, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11119491

RESUMO

The srtA gene product, SrtA, has been shown to be required for cell wall anchoring of protein A as well as virulence in the pathogenic bacterium Staphylococcus aureus. There are five major mechanisms for displaying proteins at the surface of gram-positive bacteria (P. Cossart and R. Jonquieres, Proc. Natl. Acad. Sci. USA 97:5013-5015, 2000). However, since many of the known surface proteins of gram-positive bacteria are believed to be exported and anchored via the sortase pathway, it was of interest to determine if srtA plays a similar role in other gram-positive bacteria. To that end, the srtA gene in the human oral commensal organism Streptococcus gordonii was insertionally inactivated. The srtA mutant S. gordonii exhibited a marked reduction in quantity of a specific anchored surface protein. Furthermore, the srtA mutant had reduced binding to immobilized human fibronectin and had a decreased ability to colonize the oral mucosa of mice. Taken together, these results suggest that the activity of SrtA plays an important role in the biology of nonpathogenic as well as pathogenic gram-positive cocci.


Assuntos
Aminoaciltransferases/fisiologia , Antígenos de Bactérias , Aderência Bacteriana , Proteínas da Membrana Bacteriana Externa , Proteínas de Bactérias/análise , Proteínas de Transporte/análise , Streptococcus/fisiologia , Aminoaciltransferases/genética , Animais , Parede Celular/química , Cisteína Endopeptidases , Fibronectinas/fisiologia , Genes Bacterianos , Camundongos , Mucosa Bucal/microbiologia , Streptococcus/genética
17.
Exp Toxicol Pathol ; 52(5): 465-72, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11089898

RESUMO

Lesions characterized by spindle and epithelioid cells and nuclear progesterone receptors are described in seminal vesicles of four aging mice. The lesions of two mice also contain granular metrial gland (GMG)-like cells. The same cellular details are seen in the uterine decidual reaction and the similar urinary bladder lesion in mice, also called mesenchymal tumor. Therefore, it is hypothesized that these lesions in male accessory sex glands and the urinary bladders of aging male and female mice are of mesenchymal origin with the potential for differentiation along several pathways, leading especially to lesions with decidual-like morphology, but also to lesions which contain only spindle cells. The decidual hypothesis is further supported by the occurrence of round eosinophilic granules and focal necrosis, interpreted as a sign of regression in all these lesion types. The bilateral lesions of a fifth mouse consist of spindle cells and scar-like tissue, the latter suggesting regression, and lack epithelioid and GMG-like cells. In this case, verification of the diagnosis depends on the demonstration of progesterone receptors, absent in normal glands. Uterine decidual reactions during pregnancy are brought about by priming with progesterone/estrogen, initiation through the blastocyst, and maintenance through progesterone. Experiments by others show that priming may also occur through growth factors/growth hormone, initiation through prostaglandins, and maintenance through testosterone in mice. It is hypothesized that upon such stimulation, certain cells in male accessory sex glands and the urinary bladder, possibly derived from the Muellerian ducts or other subperitoneal tissue, appear to have the potential in mice of developing into spindle and epithelioid cells, including decidual-like cells. All published uterine decidual reactions and lesions with decidual-like morphology in other organs of mice stayed within the peritoneal coverage of their respective organ and did not metastasize despite their "anaplastic", tumor-like appearance. Thus, they should be considered non-neoplastic. It is proposed to name above lesions in male accessory sex glands and urinary bladders "mesenchymal proliferation, decidual type" or "mesenchymal proliferation, spindle-cell type", depending on their cellular characteristics.


Assuntos
Envelhecimento/patologia , Decídua/patologia , Glândulas Seminais/patologia , Animais , Divisão Celular , Desmina/análise , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Músculo Liso/patologia , Gravidez , Receptores Androgênicos/análise , Bexiga Urinária/patologia
18.
Bull Soc Belge Ophtalmol ; 248: 19-22, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8044326

RESUMO

We reanalysed the current staging systems for retinoblastoma, the classification of retinoblastoma for prognosis by Reese and Ellsworth and the new Essen prognosis classification for conservative sight-saving therapy by univariant analysis. We compared the value of those classifications with one another.


Assuntos
Classificação/métodos , Neoplasias Oculares/classificação , Retinoblastoma/classificação , Neoplasias Oculares/patologia , Humanos , Retinoblastoma/patologia
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