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1.
Phys Rev Lett ; 123(2): 022501, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31386522

RESUMEN

We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F_{2} structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.

2.
Phys Rev E ; 93(2): 022117, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26986298

RESUMEN

We investigate the transition radiation on a periodically deformed interface between two dielectric media. Under the assumption that the dielectric permittivities of the media are close, a formula is derived for the spectral-angular distribution of the radiated energy in the general case of a nonstatic profile function for the separating boundary. In particular, the latter includes the case of surface waves propagating along the boundary. The numerical examples are given for triangular grating and for sinusoidal profile. We show that instead of a single peak in the backward transition radiation on a flat interface, for periodic interface one has a set of peaks. The number and the locations of the peaks depend on the incidence angle of the charge and on the period of the interface. The conditions are specified for their appearance.

3.
Phys Rev Lett ; 115(15): 152001, 2015 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-26550716

RESUMEN

Wide-angle exclusive Compton scattering and single-pion photoproduction from the proton have been investigated via measurement of the polarization transfer from a circularly polarized photon beam to the recoil proton. The wide-angle Compton scattering polarization transfer was analyzed at an incident photon energy of 3.7 GeV at a proton scattering angle of θ_{cm}^{p}=70°. The longitudinal transfer K_{LL}, measured to be 0.645±0.059±0.048, where the first error is statistical and the second is systematic, has the same sign as predicted for the reaction mechanism in which the photon interacts with a single quark carrying the spin of the proton. However, the observed value is ~3 times larger than predicted by the generalized-parton-distribution-based calculations, which indicates a significant unknown contribution to the scattering amplitude.

4.
Zh Evol Biokhim Fiziol ; 51(5): 340-6, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26856073

RESUMEN

Spontaneous bursts of action potential occurring in the ovarian and cervical horn areas as well as in uterine corpus were investigated in non-pregnant rats. The main characteristics of spikes registered simultaneously from the selected active regions under normal conditions - the frequency, amplitude, rise-rate, rise-time and half-width of peaks, were analyzed by complex electrophysiological and morpho-histochemical studies. The ovarian horn area generates high-amplitude spikes that significantly exceed the magnitude of spikes in two other areas. There are small differences between the frequency values in the above-mentioned rhythmogenic areas. The peak rise-rates are the greatest in the ovarian horn area. On the contary, the peak rise-times and the peak half-widths had the smalles values here. It is concluded that there is a significant difference between the values of activity parameters in the ovarian horn area and two other pacemaker areas localized rather close to each other. Analysis of the morphological and histochemical data revealed the greatest aggregation of functionally active cells between the myometrium and serosa in the ovarian horn area. In the cervical horn area and uterine corpus no focal accumulations of these cells were found. Thus, the morphological findings confirmed the electrophysiological results.


Asunto(s)
Relojes Biológicos , Potenciales Evocados Motores , Miometrio/fisiología , Animales , Femenino , Ratas
5.
Vaccine ; 28 Suppl 5: F77-84, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20850689

RESUMEN

This chapter outlines the epidemiology of brucellosis in the Russian Federation and in five countries bordering Russia. Since the Soviet Union's dissolution, Russia and the newly formed independent republics have failed to maintain policies to control brucellosis and other zoonotic diseases. Many of these republics, due to weak animal control and prevention systems and dangerous food preparation practices, are still burdened with the human cost of brucellosis. The final summary of this section provides an example of the successful transboundary cooperative efforts between Arizona and Mexico, which could be applied to the situation between Russia and the bordering independent republics.


Asunto(s)
Brucelosis/epidemiología , Animales , Arizona/epidemiología , Brucelosis/prevención & control , Brucelosis/veterinaria , Bovinos , Comunidad de Estados Independientes/epidemiología , Humanos , Cooperación Internacional , México/epidemiología , Políticas , Uzbekistán/epidemiología , Zoonosis/epidemiología , Zoonosis/microbiología
6.
Phytomedicine ; 12(6-7): 403-9, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16008115

RESUMEN

The safety of different doses of Kan Jang--a fixed combination of Andrographis paniculata special extract (SHA-10) and Acanthopanax senticosus--compared to two extensively used medicinal plants, Valeriana officinalis and Panax ginseng in the form of standardized extracts, has been examined. A phase I clinical study was designed to evaluate the effect on semen quality of healthy males in terms of spermatogenesis and quality of semen. The results of the study revealed no significant negative effect of Kan Jang on male semen quality and fertility, but rather a positive trend with respect to the number of spermatozoids in the whole ejaculate, the percentage of active (normokinetic) forms of spermatozoids, and fertility indexes, together with a decrease in the percentage of inactive (diskinetic) forms of spermatozoids. In the group receiving ginseng, no significant negative effects on the fertility parameters were revealed and there was a clear decrease in the percentage of diskinetic forms of spermatozoids. Subjects receiving valerian showed a temporary increase in the percentage of normokinetic spermatozoids and a decrease in diskinetic forms, but these changes had no effect on fertility indices. The results indicate that Kan Jang, ginseng and valerian are safe with respect to effects on human male sterility when administered at dose levels corresponding to approximately 3 times the human daily dose.


Asunto(s)
Andrographis , Eleutherococcus , Fitoterapia , Extractos Vegetales/farmacología , Semen/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Administración Oral , Adolescente , Adulto , Fertilidad/efectos de los fármacos , Humanos , Masculino , Panax , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Semen/citología , Espermatogénesis/efectos de los fármacos , Espermatozoides/citología , Resultado del Tratamiento , Valeriana
7.
J Heterocycl Chem ; 42(4): 557-562, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16467919

RESUMEN

This communication reports on the investigation of a new recyclization conversion of a pyrimidine ring, which can be referred to as C-C recyclization. In this reaction the nucleophile cleaves the pyrimidine ring at the N(3)-C(4) bond, and following rotation around the single C(5)-C(6) bond the new cyclization takes place. This type of recyclization has general applicability, and takes place upon alkali treatment of substituted 4-methyl-5-ethoxycarbonyl- and 4-amino-5-ethoxycarbonyl-pyrimidines (1) which are transformed respectively to 4-hydroxy-5-acetyl- and 4-hydroxy-5-carbamoylpyrimidines (2). The obtained pyrimidyl-ketones can be readily converted to their hydrazones 7-12.

8.
Neurosci Behav Physiol ; 23(1): 56-62, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8096632

RESUMEN

The neuronal organization of the hypothalamobulbar system of regulation of vascular tone was studied in experiments on cats anesthetized with chloralose and nembutal and immobilized by dithylin [suxamethonium iodide]. It was established that the descending influence of the posterior, tuberal, and paraventricular structures of the hypothalamus on the activity of antidromically identified sympathicoactive reticulospinal neurons of the ventrolateral region of the medulla oblongata is realized by mono-, oligo-, and polysynaptic mechanisms. It was shown in a series of experiments carried out in rats that animals subjected to chemical desympathization, by contrast with the controls, do not develop chronic neurogenic hypertension during a six-week stressor influence on higher nervous activity. The central and peripheral neurohumoral mechanisms of the regulation of vascular tone are discussed.


Asunto(s)
Tono Muscular/fisiología , Músculo Liso Vascular/fisiología , Neurotransmisores/fisiología , Anestesia , Animales , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Gatos , Hipotálamo/fisiología , Bulbo Raquídeo/efectos de los fármacos , Bulbo Raquídeo/fisiología , Fentolamina/farmacología , Simpatectomía Química , Sistema Nervioso Simpático/fisiología
9.
Neurosci Behav Physiol ; 11(5): 454-9, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7346716

RESUMEN

The evoked responses of identified pyramidal tract neurons of the pericruciate region of the cortex arising on stimulation of the posterior, tuberal, and anterior sections of the lateral hypothalamus were investigated in acute experiments on cats anesthetized with chloralose. THe pyramidal tract neurons recorded were situated at a depth of 0.75-2.5 mm and on stimulation of the hypothalamus discharged with a latent period of 1.6-52.5 msec. They discharged most efficiently in the case of stimulation of the caudal half of the lateral hypothalamus. The pyramidal tract neurons activated by the hypothalamus were also tested by electrocutaneous stimulation of the four limbs. Of the neurons 75% responded to stimulation of several limbs, i.e., they had a broad bilateral receptive field, while 15% reacted to stimulation of one contralateral limb (either the anterior limb or the posterior limb), i.e., they had a small contralateral receptive field. Comparison of the latent periods of the anti- and orthodromic responses of the pyramidal tract neurons did not reveal any relationship between the magnitude of the latent period of the orthodromic response (on hypothalamic or electrocutaneous stimulation) and the type of pyramidal tract neuron (according to the axonal transmission velocity). No relationship between the latent period of hypothalamic stimulation and the magnitude of the latent period of the response to a peripheral stimulus was detected either.


Asunto(s)
Hipotálamo/fisiología , Tractos Piramidales/fisiología , Animales , Gatos , Dominancia Cerebral/fisiología , Estimulación Eléctrica , Potenciales Evocados Somatosensoriales , Corteza Motora/fisiología , Neuronas/fisiología , Piel/inervación , Corteza Somatosensorial/fisiología
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