67 research outputs found
The effect of estrogen deficiency and its combination with chronic stress on the condition of periodontal in old rats
The aim of the study was to investigate the effect of ovariectomy and its combination with stress (femoral fracture) on the periodontal condition in old rats.
Materials and methods. A total of 24 white female rats were used in the experiment. The first group consisted of intact rats. Rats of the second group were subjected to an ovariectomy (OE) at the age of 2 months. Rats of the third group underwent a fracture of the one femur 1 month before they were euthanized. The animals were sacrificed at 15 months of age.
Results. The level of LPO was increased in the liver, salivary glands and alveolar bone process after experimental ovariectomy; the recession defects on molars were significantly increased. Stress (femoral fracture) aggravated the intensification of peroxidation processes in the salivary glands and liver of rats. The levels of nucleic and higher polyene fatty acids in the liver lipids were decreased in the combination of ovariectomy and stress. The level of LPO in the alveolar bone process was not changed significantly. Histomorphometric study of periodontium in rats revealed a decrease in the upper margin of epithelial attachment.
Conclusions. Experimental estrogen deficiency caused the most significant pathogenic effect on the periodontium in old rats. The obtained data demonstrate that female sex hormone deficiency is one of the mechanisms in periodontitis pathogenesis
Professional stages of a physical education teacher as determined using fitness technologies
The article gives theoretical background for the stages of professional formation of physical education teacher with the use of fitness technologies. Article contains the analysis of scientific literature and normative documents regulating the professional readiness of a physical education teacher in a higher educational institution for innovative activity.
Our work defines following stages of professional formation of the teacher of physical education with the use of fitness technologies: the stage of adaptation, the stage of professionalization and the stage of professional mastery. On the basis of the conducted research, we established incompatibility of the professional readiness of physical education teachers in higher pedagogical educational institutions to the training activity by means of fitness technologies
Current state of cadets’ physical training system at technical higher military educational institutions
En el artículo se examina el nivel de aptitud física de los cadetes que son los futuros expertos en los tipos técnicos de inteligencia. Las cualidades físicas profesionalmente importantes de los futuros expertos de los tipos técnicos de inteligencia están fundamentadas. Los cadetes de 1os 5 años de estudios participaron en la investigación. Se determina que las cualidades físicas profesionalmente importantes de los futuros expertos de los tipos técnicos de inteligencia son resistencia general, potencia, resistencia muscular estática y habilidades de coordinación. Los resultados de los cadetes en los ejercicios físicos mejoran en el cuarto año y disminuyen en el quinto año de estudio. La investigación demostró la necesidad de mejorar el actual sistema de entrenamiento físico de los cadetes.The physical fitness level of the cadets who are the future experts in the technical types of intelligence are examined in the article. The professionally important physical qualities of the future experts of the technical types of intelligence are grounded. Cadets of the 1st – 5th years of study (n=395) took part in the research. It is determined that the professionally important physical qualities of the future experts of the technical types of intelligence are general endurance, power, static muscle endurance and coordination abilities. The cadets’ results in physical exercises are improved in the 4th year and decreased in the 5th year of study. The investigation proved the necessity of improvement of the cadets’ current physical training system
THE FEATURES OF SURFACE PHENOTYPE OF BLOOD LYMPHOCYTES IN THE PATIENTS WITH TUBERCULOSIS
Abstract. Parameters of peripheral blood lymphocytes subpopulations have been studies in the patients with extensive destructive pulmonary tuberculosis caused by drug-sensitive or drug-resistant Mycobacterium tuberculosis before and in the course of specific anti-tuberculosis chemotherapy. It was revealed that in the patients before treatment, a marked immunosuppression takes place, being characterized by decrease of total T-lymphocytes and their basic regulatory and effector subpopulations. E.e., an increase in CD20+-, CD25+- and CD95+cells was observed. The completion of intensive anti-tuberculosis chemotherapy is not accompanied by correction of lymphocyte subpopulations. By contrary, in the patients with drug-sensitive pulmonary tuberculosis M. tuberculosis a sharp increase in CD95+-lymphocytes is registered. After undergoing a full course of therapy a well-noted tendency to normalization of T-lymphocytes (CD3+) quantity, as well as is regulatory populations (CD4+ and CD8+) were found. The level of CD95+-lymphocytes remained increased in the patients with pulmonary tuberculosis caused by drug-resistant M. tuberculosis
Measurement of Exclusive Electroproduction Structure Functions and their Relationship to Transversity GPDs
Exclusive electroproduction at a beam energy of 5.75 GeV has been
measured with the Jefferson Lab CLAS spectrometer. Differential cross sections
were measured at more than 1800 kinematic values in , , , and
, in the range from 1.0 to 4.6 GeV,\ up to 2 GeV,
and from 0.1 to 0.58. Structure functions and were extracted as functions of for each of
17 combinations of and . The data were compared directly with two
handbag-based calculations including both longitudinal and transversity GPDs.
Inclusion of only longitudinal GPDs very strongly underestimates and fails to account for and ,
while inclusion of transversity GPDs brings the calculations into substantially
better agreement with the data. There is very strong sensitivity to the
relative contributions of nucleon helicity flip and helicity non-flip
processes. The results confirm that exclusive electroproduction offers
direct experimental access to the transversity GPDs.Comment: 6 pages, 2 figure
Cross sections for the γp→K*+Λ and γp→K*+Σ0 reactions measured at CLAS
The first high-statistics cross sections for the reactions γp→K*+Λ and γp→K*+Σ0 were measured using the CLAS detector at photon energies between threshold and 3.9 GeV at the Thomas Jefferson National Accelerator Facility. Differential cross sections are presented over the full range of the center-of-mass angles, and then fitted to Legendre polynomials to extract the total cross section. Results for the K*+Λ final state are compared with two different calculations in an isobar and a Regge model, respectively. Theoretical calculations significantly underestimate the K*+Λ total cross sections between 2.1 and 2.6 GeV, but are in better agreement with present data at higher photon energies
Transverse Polarization of in Photoproduction on a Hydrogen Target in CLAS
Experimental results on the hyperon transverse polarization
in photoproduction on a hydrogen target using the CLAS detector at Jefferson
laboratory are presented. The was reconstructed in the
exclusive reaction via the
decay mode. The was reconstructed in the
invariant mass of two oppositely charged pions with the identified in
the missing mass of the detected final state. Experimental data
were collected in the photon energy range = 1.0-3.5 GeV
( range 1.66-2.73 GeV). We observe a large negative polarization of
up to 95%. As the mechanism of transverse polarization of hyperons produced in
unpolarized photoproduction experiments is still not well understood, these
results will help to distinguish between different theoretical models on
hyperon production and provide valuable information for the searches of missing
baryon resonances.Comment: pages 1
Demonstration of a novel technique to measure two-photon exchange effects in elastic scattering
The discrepancy between proton electromagnetic form factors extracted using
unpolarized and polarized scattering data is believed to be a consequence of
two-photon exchange (TPE) effects. However, the calculations of TPE corrections
have significant model dependence, and there is limited direct experimental
evidence for such corrections. We present the results of a new experimental
technique for making direct comparisons, which has the potential to
make precise measurements over a broad range in and scattering angles. We
use the Jefferson Lab electron beam and the Hall B photon tagger to generate a
clean but untagged photon beam. The photon beam impinges on a converter foil to
generate a mixed beam of electrons, positrons, and photons. A chicane is used
to separate and recombine the electron and positron beams while the photon beam
is stopped by a photon blocker. This provides a combined electron and positron
beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen
target. The large acceptance CLAS detector is used to identify and reconstruct
elastic scattering events, determining both the initial lepton energy and the
sign of the scattered lepton. The data were collected in two days with a
primary electron beam energy of only 3.3 GeV, limiting the data from this run
to smaller values of and scattering angle. Nonetheless, this measurement
yields a data sample for with statistics comparable to those of the
best previous measurements. We have shown that we can cleanly identify elastic
scattering events and correct for the difference in acceptance for electron and
positron scattering. The final ratio of positron to electron scattering:
for GeV and
Вплив естрогенної недостатності та її поєднання з хронічним стресом на стан пародонта старих щурів
Цель работы – изучение влияния овариэктомии и ее сочетания со стрессом (перелом бедренной кости) на состояние
пародонта старых крыс.
Материалы и методы. Опыт проведен на 24 белых крысах-самках стадного разведения. I группа – интактная. В 2-месячном
возрасте крысам II группы была произведена овариэктомия (ОЭ). Перелом бедренной кости одной из задних конечностей
произведен крысам III группы за 1 месяц до забоя. На момент забоя крысы были в возрасте 15 месяцев.
Результаты. В условиях экспериментальной овариэктомии в печени, слюнных железах и кости альвеолярного отростка
повышался уровень перекисного окисления липидов (ПОЛ); существенно увеличивалось обнажение корней моляров.
Стресс (перелом бедра) усугублял усиление перекисных процессов в слюнных железах и печени крыс. При сочетании
овариэктомии и стресса в печени снижался уровень нуклеиновых и высших полиеновых жирных кислот в ее липидах.
Уровень ПОЛ в кости альвеолярного отростка существенно не изменялся. При гистоморфометрическом исследовании
пародонта крыс отмечено снижение верхнего края эпителиального прикрепления.
Выводы. Наиболее значительное патогенное воздействие для пародонта – экспериментальная эстрогенная недостаточность у старых крыс. Полученные данные демонстрируют, что одним из механизмов развития пародонтита
является недостаточность женских половых гормонов.The aim of the study was to investigate the effect of ovariectomy and its combination with stress (femoral fracture) on the periodontal
condition in old rats.
Materials and methods. A total of 24 white female rats were used in the experiment. The frst group consisted of intact rats. Rats
of the second group were subjected to an ovariectomy (OE) at the age of 2 months. Rats of the third group underwent a fracture
of the one femur 1 month before they were euthanized. The animals were sacrifced at 15 months of age.
Results. The level of LPO was increased in the liver, salivary glands and alveolar bone process after experimental ovariectomy;
the recession defects on molars were signifcantly increased. Stress (femoral fracture) aggravated the intensifcation of peroxidation
processes in the salivary glands and liver of rats. The levels of nucleic and higher polyene fatty acids in the liver lipids were
decreased in the combination of ovariectomy and stress. The level of LPO in the alveolar bone process was not changed signifcantly.
Histomorphometric study of periodontium in rats revealed a decrease in the upper margin of epithelial attachment.
Conclusions. Experimental estrogen defciency caused the most signifcant pathogenic effect on the periodontium in old rats.
The obtained data demonstrate that female sex hormone defciency is one of the mechanisms in periodontitis pathogenesis.Мета роботи – вивчення впливу оваріектомії та її поєднання зі стресом (перелом стегнової кістки) на стан пародонта
старих щурів.
Матеріали та методи. Дослід проведено на 24 білих щурах-самках стадного розведення. I група – інтактна. У 2-місячних
щурів ІІ групи виконали оваріектомію (ОЕ). Перелом стегнової кістки однієї із задніх кінцівок здійснили щурам ІІІ групи за
1 місяць до забиття. На момент забиття щури були віком 15 місяців.
Результати. В умовах експериментальної оваріектомії в печінці, слинних залозах і кістці альвеолярного відростка підвищувався рівень перекисного окислення ліпідів (ПОЛ); істотно збільшувалось оголення коренів молярів. Стрес (перелом
стегна) збільшував посилення перекисних процесів у слинних залозах і печінці щурів. При поєднанні оваріектомії та стресу
в печінці знижувався рівень нуклеїнових і вищих полієнових жирних кислот в її ліпідах. Рівень ПОЛ у кістці альвеолярного
відростка суттєво не змінювався. Під час гістоморфометричного дослідження пародонта щурів виявили зниження верхнього
краю епітеліального прикріплення.
Висновки. Найбільш значущим патогенним впливом для пародонта була експериментальна естрогенна недостатність
у старих щурів. Результати показують, що одним із механізмів розвитку пародонтиту є недостатність жіночих статевих
гормонів
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