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1.
Phys Rev Lett ; 130(5): 051802, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36800478

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-34860065

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-31702305

RESUMEN

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.
Ross Fiziol Zh Im I M Sechenova ; 84(7): 663-71, 1998 Jul.
Artículo en Ruso | MEDLINE | ID: mdl-9805778

RESUMEN

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.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/fisiología , Sistema Linfático/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Vasoconstricción/efectos de los fármacos , Animales , Péptido Relacionado con Gen de Calcitonina/química , Humanos , Técnicas In Vitro , Intestino Delgado/efectos de los fármacos , Sistema Linfático/fisiología , Masculino , Mesenterio/efectos de los fármacos , Fragmentos de Péptidos/química , Ratas , Ratas Wistar
6.
Invest Ophthalmol Vis Sci ; 38(1): 167-75, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9008641

RESUMEN

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.


Asunto(s)
Luteína/metabolismo , Mácula Lútea/metabolismo , Retina/metabolismo , Tubulina (Proteína)/metabolismo , beta Caroteno/análogos & derivados , Marcadores de Afinidad , Animales , Western Blotting , Bovinos , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Humanos , Luteína/aislamiento & purificación , Mácula Lútea/química , Unión Proteica , Retina/química , Tubulina (Proteína)/aislamiento & purificación , Xantófilas , Zeaxantinas , beta Caroteno/aislamiento & purificación , beta Caroteno/metabolismo
7.
Ross Fiziol Zh Im I M Sechenova ; 83(11-12): 115-21, 1997.
Artículo en Ruso | MEDLINE | ID: mdl-9541963

RESUMEN

An increased suppression of electrical activity of the cardiac inferior nerve by the baroreflex during norepinephrine infusion can be eliminated by a preliminary infusion of monoamine. The data obtained corroborated our previous findings that an increase in arterial pressure due to norepinephrine infusion was essential for catecholamine increasing the baroreflex inhibition of electrical activity in sympathetic nerves.


Asunto(s)
Barorreflejo/efectos de los fármacos , Encéfalo/efectos de los fármacos , Norepinefrina/farmacología , Sistema Nervioso Simpático/efectos de los fármacos , Animales , Barorreflejo/fisiología , Presión Sanguínea/efectos de los fármacos , Encéfalo/fisiología , Seno Carotídeo/inervación , Seno Carotídeo/fisiología , Gatos , Estimulación Eléctrica , Corazón/efectos de los fármacos , Corazón/inervación , Corazón/fisiología , Infusiones Intravenosas , Riñón/efectos de los fármacos , Riñón/inervación , Riñón/fisiología , Norepinefrina/administración & dosificación , Norepinefrina/metabolismo , Presorreceptores/efectos de los fármacos , Presorreceptores/fisiología , Sistema Nervioso Simpático/fisiología
11.
Fiziol Zh SSSR Im I M Sechenova ; 77(9): 224-31, 1991 Sep.
Artículo en Ruso | MEDLINE | ID: mdl-1666608

RESUMEN

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.


Asunto(s)
Arterias/fisiopatología , Hipertensión Renovascular/fisiopatología , Animales , Aorta/efectos de los fármacos , Aorta/fisiopatología , Arterias/efectos de los fármacos , Enfermedad Crónica , Relación Dosis-Respuesta a Droga , Arteria Femoral/efectos de los fármacos , Arteria Femoral/fisiopatología , Masculino , Arterias Mesentéricas/efectos de los fármacos , Arterias Mesentéricas/fisiopatología , Microcirculación/efectos de los fármacos , Microcirculación/fisiopatología , Norepinefrina/farmacología , Ratas , Ratas Endogámicas
12.
Fiziol Zh SSSR Im I M Sechenova ; 77(6): 34-41, 1991 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-1665817

RESUMEN

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.


Asunto(s)
Catecolaminas/farmacología , Mesenterio/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Sistema Nervioso Simpático/efectos de los fármacos , Animales , Arteriolas/efectos de los fármacos , Arteriolas/inervación , Arteriolas/fisiología , Mesenterio/irrigación sanguínea , Mesenterio/inervación , Microinyecciones , Músculo Liso Vascular/inervación , Músculo Liso Vascular/fisiología , Oxidopamina , Conejos , Simpatectomía Química , Sistema Nervioso Simpático/fisiología
13.
Zh Evol Biokhim Fiziol ; 26(1): 136-8, 1990.
Artículo en Ruso | MEDLINE | ID: mdl-2360377

RESUMEN

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.


Asunto(s)
Crecimiento/fisiología , Arterias Mesentéricas/fisiología , Envejecimiento/efectos de los fármacos , Envejecimiento/fisiología , Animales , Animales Recién Nacidos , Arteriolas/efectos de los fármacos , Arteriolas/fisiología , Crecimiento/efectos de los fármacos , Masculino , Arterias Mesentéricas/efectos de los fármacos , Norepinefrina/farmacología , Conejos
14.
Vopr Med Khim ; 36(1): 84-7, 1990.
Artículo en Ruso | MEDLINE | ID: mdl-2343584

RESUMEN

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.


Asunto(s)
Adenilil Ciclasas/metabolismo , Aorta/enzimología , Hipertensión Renal/enzimología , Miocardio/enzimología , Inhibidores de Adenilato Ciclasa , Animales , Activación Enzimática , Guanosina Trifosfato/farmacología , Isoproterenol/farmacología , Masculino , Músculo Liso Vascular/enzimología , Ratas , Ratas Endogámicas , Fluoruro de Sodio/farmacología
16.
Fiziol Zh SSSR Im I M Sechenova ; 75(3): 386-90, 1989 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-2547669

RESUMEN

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.


Asunto(s)
Eritrocitos/enzimología , Isquemia/enzimología , Riñón/irrigación sanguínea , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Riñón/enzimología , Riñón/patología , Masculino , Ratas , Ratas Endogámicas , ATPasa Intercambiadora de Sodio-Potasio/sangre , Factores de Tiempo
17.
Fiziol Zh SSSR Im I M Sechenova ; 72(2): 176-82, 1986 Feb.
Artículo en Ruso | MEDLINE | ID: mdl-3699182

RESUMEN

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.


Asunto(s)
Aorta/inervación , Presión Sanguínea , Presorreceptores/fisiología , Sistema Vasomotor/fisiología , Animales , Fibras Autónomas Posganglionares/fisiología , Seno Carotídeo/fisiología , Gatos , Frecuencia Cardíaca , Riñón/inervación , Masculino , Reflejo/fisiología , Nervio Vago/fisiología
18.
Fiziol Zh SSSR Im I M Sechenova ; 71(6): 719-23, 1985 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-4029440

RESUMEN

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.


Asunto(s)
Humor Acuoso/fisiología , Catecolaminas/análisis , Ojo/inervación , Sistema Nervioso Simpático/fisiología , Animales , Gatos , Cuerpo Ciliar/análisis , Epinefrina/análisis , Presión Intraocular , Iris/análisis , Norepinefrina/análisis , Simpatectomía
19.
Acta Physiol Scand ; 111(4): 435-40, 1981 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7304205

RESUMEN

The adrenergic system of the beluga, Huso huso, was studied by glyoxylic acid fluorescence histochemistry, analyses of catecholamine content in various organs and studies of the effects of acetylcholine and adrenaline on isolated strip preparations from blood vessels, spleen, atrium and ventricle. Chromaffin cells were found mainly in the walls of the posterior cardinal veins, and to some extent also in the wall of the celiaco-mesenteric artery. The plasma concentration of adrenaline was high enough to affect the contraction force of the isolated atrial and ventricular strips, thus adding an adrenergic component to a possible cholinergic inhibitory vagal control of the heart. Fluorescence histochemistry revealed no direct adrenergic innervation of the heart, but blood vessels in the heart and elsewhere received a rich supply of adrenergic nerve terminals. Adrenaline contracted the celiaco-mesenteric artery and the spleen, and produced positive inotropic effects on the paced atrial and ventricular strip preparations. Acetylcholine contracted the ventral aorta and the celiaco-mesenteric artery, and reduced the contraction force of paced ventricular and, especially, atrial preparations. It is concluded that the beluga has a well developed adrenergic system consisting of both chromaffin cells and adrenergic neurons with varicose nerve terminals of the type found in the higher vertebrates.


Asunto(s)
Fibras Adrenérgicas/fisiología , Peces/fisiología , Acetilcolina/farmacología , Animales , Vasos Sanguíneos/efectos de los fármacos , Sistema Cromafín/fisiología , Epinefrina/análisis , Epinefrina/farmacología , Fluorescencia , Corazón/efectos de los fármacos , Histocitoquímica , Neuronas/fisiología , Norepinefrina/análisis , Bazo/efectos de los fármacos
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