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1.
Phys Rev Lett ; 130(5): 051802, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800478

RESUMO

The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q^{2} (squared four-momentum transfer) and energy, in the range 1 GeV≤E_{ν}<6 GeV. Detailed comparisons are made to the predictions of the GENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the others consistently across all three cross sections measured, though some models have especially good or poor agreement in the single differential cross section vs Q^{2}.

2.
Phys Rev Lett ; 127(20): 201801, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34860065

RESUMO

This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of 12.51×10^{20} protons-on-target from the NuMI beam at Fermilab running in antineutrino mode. A total of 121 of neutral-current candidates are observed at the far detector, compared to a prediction of 122±11(stat.)±15(syst.) assuming mixing only between three active flavors. No evidence for ν[over ¯]_{µ}→ν[over ¯]_{s} oscillation is observed. Interpreting this result within a 3+1 model, constraints are placed on the mixing angles θ_{24}<25° and θ_{34}<32° at the 90% C.L. for 0.05 eV^{2}≤Δm_{41}^{2}≤0.5 eV^{2}, the range of mass splittings that produces no significant oscillations at the near detector. These are the first 3+1 confidence limits set using long-baseline accelerator antineutrinos.

3.
Phys Rev Lett ; 123(15): 151803, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31702305

RESUMO

The NOvA experiment has seen a 4.4σ signal of ν[over ¯]_{e} appearance in a 2 GeV ν[over ¯]_{µ} beam at a distance of 810 km. Using 12.33×10^{20} protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν[over ¯]_{µ}→ν[over ¯]_{e} candidates with a background of 10.3 and 102 ν[over ¯]_{µ}→ν[over ¯]_{µ} candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm_{32}^{2}|=2.48_{-0.06}^{+0.11}×10^{-3} eV^{2}/c^{4} and sin^{2}θ_{23} in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δ_{CP}=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ_{23} values in the upper octant by 1.6σ.

4.
Invest Ophthalmol Vis Sci ; 38(1): 167-75, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9008641

RESUMO

PURPOSE: To investigate the biochemical mechanisms responsible for the specific uptake, concentration, and stabilization of the carotenoids lutein and zeaxanthin in the macula. METHODS: Soluble extracts of bovine retina mixed with radioactive carotenoids were purified by hydrophobic interaction, ion exchange, and gel filtration chromatography. Carotenoid-associated proteins in these purified preparations were identified through photoaffinity labeling and protein microsequencing. Similar purifications on human macular tissue without the addition of exogenous carotenoids also were performed. RESULTS: Experiments on bovine retinal tissue demonstrated that tubulin is the major soluble carotenoid-binding protein. When soluble extracts of human macular protein were examined, the endogenous carotenoids lutein and zeaxanthin were found to copurify with tubulin. CONCLUSIONS: Tubulin is found in abundance in the receptor axon layer of the fovea, where it can serve as a locus for the deposition of the high concentrations of macular carotenoids found there. The binding interaction of carotenoids and tubulin in the Henle's fiber layer could play an important role in the photoprotective effects of the macular carotenoids against the progression of age-related macular degeneration. The association of carotenoids with tubulin, a protein that can form highly ordered linear arrays, may provide an explanation for the dichroic phenomenon of Haidinger's brushes.


Assuntos
Luteína/metabolismo , Macula Lutea/metabolismo , Retina/metabolismo , Tubulina (Proteína)/metabolismo , beta Caroteno/análogos & derivados , Marcadores de Afinidade , Animais , Western Blotting , Bovinos , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Humanos , Luteína/isolamento & purificação , Macula Lutea/química , Ligação Proteica , Retina/química , Tubulina (Proteína)/isolamento & purificação , Xantofilas , Zeaxantinas , beta Caroteno/isolamento & purificação , beta Caroteno/metabolismo
5.
Br J Pharmacol ; 54(3): 383-8, 1975 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-169934

RESUMO

1 The effects of gamma-aminobutyric acid (GABA), beta-guanidinopropionic acid (betaGP) and picrotoxin on the pre- and post-synaptic receptors of the hermit crab neuromuscular junction were studied quantitatively usine electrophysiological techniques. Reductions in excitatory junction potential (e.j.p.) amplitude and membrane resistance were measured simultaneously from the same cells. 2 The pre- and post-synaptic receptors were activated by the same order of concentration of GABA, whereas betaGP stimulated the pre-synaptic receptors at a concentration ten times lower than was required to affect the post-synaptic membrane. 3 Picrotoxin appeared to antagonize the pre-synaptic action of betaGP in a competitive manner. The affinity constants (+/- s.e. mean) for picrotoxin 5 times 10(-6)M and 2 times 10(-4)M were 6.80(+/-0.46) times 10(5)M-1 and 6.42(+/-1.8) times 10(5)M-1 respectively. 4 The effect of GABA on e.j.p. amplitude also appeared to be antagonized competitively by picrotoxin whereas the post-synaptic effect was antagonized in a non-competitive manner. 5 Possible differences in the nature of the pre- and post-synaptic receptors are discussed.


Assuntos
Anomuros/fisiologia , Junção Neuromuscular/efeitos dos fármacos , Receptores de Neurotransmissores/efeitos dos fármacos , Animais , Depressão Química , Potenciais Evocados/efeitos dos fármacos , Guanidinas/farmacologia , Técnicas In Vitro , Picrotoxina/farmacologia , Propionatos/farmacologia , Membranas Sinápticas/efeitos dos fármacos , Ácido gama-Aminobutírico/farmacologia
6.
Fiziol Zh SSSR Im I M Sechenova ; 77(6): 34-41, 1991 Jun.
Artigo em Russo | MEDLINE | ID: mdl-1665817

RESUMO

The sensitivity of smooth muscle cells' adrenoreceptors to noradrenaline (NA) and dopamine (DA) was studied in intact and desympathised arterial microvessels of the rabbit mesentery. The arterioles differed from each other in their sensitivity to catecholamines depending on their diameter. However, in conditions of chemical desympathisation, the sensitivity to NA and DA increased in all the microvessels whereas the degree of narrowing of the microvessels' lumen remained practically the same. These findings suggest a heterogeneous character of physiological properties of vascular smooth muscle cells within the arterial part of the microcirculatory module of the rabbit mesentery.


Assuntos
Catecolaminas/farmacologia , Mesentério/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/inervação , Arteríolas/fisiologia , Mesentério/irrigação sanguínea , Mesentério/inervação , Microinjeções , Músculo Liso Vascular/inervação , Músculo Liso Vascular/fisiologia , Oxidopamina , Coelhos , Simpatectomia Química , Sistema Nervoso Simpático/fisiologia
7.
Fiziol Zh SSSR Im I M Sechenova ; 71(6): 719-23, 1985 Jun.
Artigo em Russo | MEDLINE | ID: mdl-4029440

RESUMO

After removal of the supper cervical sympathetic ganglion in cats followed by increase of the intraocular pressure from 20 to 32 mm Hg, the outflow of intraocular fluid was sharply enhanced due to lowering tone of tissues of the eye drainage apparatus in the desympathised eye. Noradrenaline was found to reduce sharply by the 4th-5th day in the desympathised eye's tissues due to degenerative processes whereas accumulation of noradrenaline by the 6th-8th day occurred on account of humoral factors.


Assuntos
Humor Aquoso/fisiologia , Catecolaminas/análise , Olho/inervação , Sistema Nervoso Simpático/fisiologia , Animais , Gatos , Corpo Ciliar/análise , Epinefrina/análise , Pressão Intraocular , Iris/análise , Norepinefrina/análise , Simpatectomia
8.
Fiziol Zh SSSR Im I M Sechenova ; 77(9): 224-31, 1991 Sep.
Artigo em Russo | MEDLINE | ID: mdl-1666608

RESUMO

In rats with experimental hypertension, mesenteric artery revealed a hypersensitivity to noradrenaline whereas aorta did not differ from normal values of this parameter. The sensitivity of femoral artery was lowered. The microarterioles of hypertensive animals manifested a lower sensitivity to noradrenaline as well. This data suggests that arterial vessels manifest a regional heterogeneity of their functional properties in chronic birenal renovascular hypertension.


Assuntos
Artérias/fisiopatologia , Hipertensão Renovascular/fisiopatologia , Animais , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Artérias/efeitos dos fármacos , Doença Crônica , Relação Dose-Resposta a Droga , Artéria Femoral/efeitos dos fármacos , Artéria Femoral/fisiopatologia , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiopatologia , Microcirculação/efeitos dos fármacos , Microcirculação/fisiopatologia , Norepinefrina/farmacologia , Ratos , Ratos Endogâmicos
9.
Fiziol Zh SSSR Im I M Sechenova ; 72(2): 176-82, 1986 Feb.
Artigo em Russo | MEDLINE | ID: mdl-3699182

RESUMO

In anesthetized cats, the enhancement of sympathetic activity and increase of the blood pressure in exclusion of afferents (section of vagosympathetic trunks and clamping of common carotid arteries) as well as the disappearance of the activity in enhanced afferentation, were shown to be transient and to disappear within a few minutes-scores of minutes in spite of the going on deafferentation or enhancement of afferentation. The afferent influences from the arterial baroreceptors seem to have no major significance for the long-term control of sympathetic tone.


Assuntos
Aorta/inervação , Pressão Sanguínea , Pressorreceptores/fisiologia , Sistema Vasomotor/fisiologia , Animais , Fibras Autônomas Pós-Ganglionares/fisiologia , Seio Carotídeo/fisiologia , Gatos , Frequência Cardíaca , Rim/inervação , Masculino , Reflexo/fisiologia , Nervo Vago/fisiologia
10.
Fiziol Zh SSSR Im I M Sechenova ; 75(3): 386-90, 1989 Mar.
Artigo em Russo | MEDLINE | ID: mdl-2547669

RESUMO

The renovascular hypertension in the Wistar rats was induced by clipping both renal arteries. Within 3-4 weeks arterial pressure (AP) increased to maximal values. According to AP, the rats were divided into two groups: with AP less than or equal to 170 mm Hg and greater than 170 mm Hg. In 5-6 or 10-11 weeks the animals were decapitated and the Na,K-ATPase activities in the wholesome erythrocytes, their ghosts, and the cortex and medulla of kidneys were studied. Changes of the enzyme activity were only found in the medulla. A decreased enzyme activity (-20%) was revealed in the rats with AP less than or equal to 170 mm Hg within 5-6 weeks after renal ischemia, the activity increasing again in 10-11 weeks after the operation. The decreasing of Na,K-ATPase activity within 5-6 weeks after renal ischemia could be a mechanism of adaptation of the salt-water balance in animals.


Assuntos
Eritrócitos/enzimologia , Isquemia/enzimologia , Rim/irrigação sanguínea , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Rim/enzimologia , Rim/patologia , Masculino , Ratos , Ratos Endogâmicos , ATPase Trocadora de Sódio-Potássio/sangue , Fatores de Tempo
11.
Zh Evol Biokhim Fiziol ; 26(1): 136-8, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2360377

RESUMO

Television microscopic studies have been made of the reaction of mesenterial metarterioles to noradrenalin in newborn, 10- and 30-day rabbits. The results obtained show the existence of postnatal changes in the reactivity of arterioles with a diameter 20-25 mu. Within the period investigated, noradrenalin sensitivity of metarterioles decreases whereas their contractile activity increases. It is suggested that formation of functional properties of metarterioles is not accomplished to the birth of rabbits.


Assuntos
Crescimento/fisiologia , Artérias Mesentéricas/fisiologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Animais , Animais Recém-Nascidos , Arteríolas/efeitos dos fármacos , Arteríolas/fisiologia , Crescimento/efeitos dos fármacos , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Norepinefrina/farmacologia , Coelhos
12.
Vopr Med Khim ; 36(1): 84-7, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2343584

RESUMO

Properties of the adenylate cyclase system were simultaneously studied in heart and aorta of rats with renovascular hypertension. Under conditions of the pathology molecular interactions between adrenoreceptors, regulating proteins (N-proteins) and catalytic subunit of the adenylate cyclase system were deteriorated in rat myocardium as well as functions of the regulating component were impaired in the adenylate cyclase system of aorta smooth muscles.


Assuntos
Adenilil Ciclases/metabolismo , Aorta/enzimologia , Hipertensão Renal/enzimologia , Miocárdio/enzimologia , Inibidores de Adenilil Ciclases , Animais , Ativação Enzimática , Guanosina Trifosfato/farmacologia , Isoproterenol/farmacologia , Masculino , Músculo Liso Vascular/enzimologia , Ratos , Ratos Endogâmicos , Fluoreto de Sódio/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-987101

RESUMO

The semen of animals in spontaneous and experimental leptospirosis was investigated by bacteriological, immunological and biological methods. It has been found that pathogenic leptospirae (L. pomona, L. hebdomadis) are well preserved in the semen and in media used for its dilution. Leptospirae are eliminated with the semen. The initial strain of the agent was isolated from the semen and secretions of 6 out of 26 experimentally infected rabbits and 4 spontaneously recovered bulls (L. hebdomadis). Specific leptospiral antibodies appear in the semen of infected animals. The dynamics of the titre of these antibodies corresponds to the dynamics of the antibody titre in the blood. It is recommended to use the sement for the agglutination reaction. The application of semen infected with pathogenic leptospirae for artificial insemination causes the animals falling ill with leptospirosis accompanied by abortions, reduced fertility and stillbirths of rabbits.


Assuntos
Doenças dos Bovinos/transmissão , Inseminação Artificial/veterinária , Leptospirose/veterinária , Animais , Anticorpos Antibacterianos/análise , Formação de Anticorpos , Bovinos , Cricetinae , Feminino , Leptospira/imunologia , Leptospira/isolamento & purificação , Leptospirose/transmissão , Masculino , Coelhos , Sêmen/imunologia , Sêmen/microbiologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-987112

RESUMO

The semen of animals in spontaneous and experimental leptospirosis was investigated by bacteriological, immunological and biological methods. It has been found that pathogenic leptospirae (L. pomona, L. hebdomadis) are well preserved in the semen and in media used for its dilution. Leptospirae are eliminated with the semen. The initial strain of the agent was isolated from the semen and secretions of 6 out of 26 experimentally infected rabbits and 4 spontaneously recovered bulls (L. hebdomadis). Specific leptospiral antibodies appear in the semen of infected animals. The dynamics of the titre of these antibodies corresponds to the dynamics of the antibody titre in the blood. It is recommended to use the semen for the agglutination reaction. The application of semen infected with pathogenic leptospirae for artificial insemination causes the animals falling ill with leptospirosis accompanied by abortions, reduced fertility and stillbirths of rabbits.


Assuntos
Inseminação , Leptospirose/transmissão , Animais , Anticorpos Antibacterianos/análise , Bovinos , Cricetinae , Feminino , Inseminação Artificial , Leptospira/isolamento & purificação , Leptospira/patogenicidade , Leptospirose/imunologia , Masculino , Coelhos , Sêmen/imunologia , Sêmen/microbiologia
19.
Ross Fiziol Zh Im I M Sechenova ; 84(7): 663-71, 1998 Jul.
Artigo em Russo | MEDLINE | ID: mdl-9805778

RESUMO

Effects of some fragments of alpha-calcitonine gene-related peptide (alpha-CGRP) on the collector lymphatic vessels of the rat small intestine mesenterium, were studied. All the fragments excepting alpha-CGRP (21-24) and (21-31) activate motility of the lymphatic vessels enhancing phasic contractions of the walls. Presence of aminoacid residuals in the 20-29 area is "critical" for realising vasoactive properties by these fragments.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/fisiologia , Sistema Linfático/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Peptídeo Relacionado com Gene de Calcitonina/química , Humanos , Técnicas In Vitro , Intestino Delgado/efeitos dos fármacos , Sistema Linfático/fisiologia , Masculino , Mesentério/efeitos dos fármacos , Fragmentos de Peptídeos/química , Ratos , Ratos Wistar
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