A
bstract
The cross section of the process
e
+
e
−
→
π
+
π
−
has been measured in the Spherical Neutral Detector (SND) experiment at the VEPP-2000
e
+
e
−
collider VEPP-2000 in the energy region 525
...<
s
<
883 MeV. The measurement is based on data with an integrated luminosity of about 4.6 pb
−
1
. The systematic uncertainty of the cross section determination is 0.8% at
s
>
0
.
600 GeV. The
ρ
meson parameters are obtained as
m
ρ
= 775
.
3 ± 0
.
5 ± 0
.
6 MeV, Γ
ρ
= 145
.
6 ± 0
.
6 ± 0
.
8 MeV,
B
ρ
→
e
+
e−
×
B
ρ
→
π
+
π−
= (4
.
89 ± 0
.
02 ± 0
.
04) × 10
−
5
, and the parameters of the
e
+
e
−
→
ω
→
π
+
π
−
process, suppressed by
G
-parity, as
B
ω
→
e
+
e−
×
B
ω
→
π
+
π−
= (1
.
32 ± 0
.
06 ± 0
.
02) × 10
−
6
and and
ϕ
ρω
= 110
.
7 ± 1
.
5 ± 1
.
0 degrees.
The process
e
+
e
-
→
n
n
¯
is studied in the experiment at the VEPP-2000
e
+
e
-
collider with the SND detector. The technique of the time measurements in the multichannel NaI(Tl) electromagnetic ...calorimeter is used to select
n
n
¯
events. The value of the measured cross section in the center-of-mass energy range from 1.894 to 2 GeV varies from 0.5 to 0.35 nb. The effective neutron timelike form factor is derived from the measured cross section and compared with the proton form factor. The ratio of the neutron electric and magnetic form factors is obtained from the analysis of the antineutron polar angle distribution and found to be consistent with unity.
The process
e
+
e
-
→
η
η
γ
is studied in the center-of-mass energy range 1.17–2.00 GeV using data with an integrated luminosity of 201 pb
-
1
collected by the SND detector at the VEPP-2000
e
+
e
-
...collider. The
e
+
e
-
→
η
η
γ
cross section is measured for the first time. It is shown that the dominant mechanism of this reaction is the transition through the
ϕ
η
intermediate state. Our result on the
e
+
e
-
→
η
η
γ
cross section is consistent with the
e
+
e
-
→
ϕ
η
measurement in the
ϕ
→
K
+
K
-
mode. The search for radiative processes contributing to the
e
+
e
-
→
η
η
γ
cross section is performed, and no significant signal is observed.
Introduction
. Early relevant is the early prediction of the development of type 2 diabetes (T2D), which allows to prevent the development of the disease and its complications. For the purpose ...of screening, scales for assessing the risk of its development based on the results of questionnaires are used, but at the moment there are no questionnaires against employees of law enforcement agencies professionally related to psycho-emotional stress.
Aim
. Assessment of the prognostic value of the original mathematical model of the VERADIV to assess the risk of developing T2D in comparison with the FINDRISC questionnaires and a DIARISK regarding the cohort of military personnel.
Materials and methods.
212 subjects from among military personnel under a young and middle -aged contract with a waist of the a avyinary poles and a representative control group from among civilians (60 people) were selected for prospective cohort research. At the first stage of the study, anthropometric psychophysiological indicators were studied, as well as laboratory data aimed at assessing the state of the endocrine function of the pancreas and the degree of insulin resistance. After 3 years, the state of carbohydrate exchange of subjects with the assessment of factors that influenced the development of new cases of prediabetes and T2D was evaluated. Based on the data obtained, an index of the VERADIV was developed, avaluating the likelihood of risk of developing T2D among military personnel. The most important stage in the work was a comparative assessment of the prognostic value of the model of the FINDRISC verasa and the DIARISK, set forth in this article.
Results and discussion.
The mathematical model of predicting the risk of T2D, from the age, from the HOMA-IR index, allows the points of aggressiveness and volitional self -control in 91.9% of cases, correctly predict the absence of the development of T2D after 3 years, and during the same period the probability of manifestation of T2D – in 91.7% of cases. For cohorts of military personnel, the specificity and sensitivity of the FINDRISC questionnaire amounted to 69.5 and 75%, respectively. The specificity and sensitivity of the DIARISK questionnaire amounted to 75%.
Conclusion
. The results of the study indicate the importance of taking into account insulin resistance and psycho-emotional stress in assessing the risk of developing T2D among military personnel, which confirmed the high prognostic value of the vendiv scale.
The results of studying ferroelectric materials obtained at the Institute of Automation and Electrometry of the Siberian Branch of the Russian Academy of Sciences in 1973-2020 are reported. ...Mechanisms of the photovoltaic effect and photorefraction, emergence and role of polar regions in ferroelectric crystals, methods of detection of polar regions, and mechanisms of manifestation of the displacive and order-disorder phase transitions in various ferroelectrics are discussed. The results of experimental and theoretical investigations allow one to conclude that imperfections of a crystal structure play a key role in phenomena observed in ferroelectrics.
Multiple approaches utilizing viral and DNA vectors have shown promise in the development of an effective vaccine against HIV. In this study, an alternative replication-defective flavivirus vector, ...RepliVax (RV), was evaluated for the delivery of HIV-1 immunogens. Recombinant RV-HIV viruses were engineered to stably express clade C virus Gag and Env (gp120TM) proteins and propagated in Vero helper cells. RV-based vectors enabled efficient expression and correct maturation of Gag and gp120TM proteins, were apathogenic in a sensitive suckling mouse neurovirulence test, and were similar in immunogenicity to recombinant poxvirus NYVAC-HIV vectors in homologous or heterologous prime-boost combinations in mice. In a pilot NHP study, immunogenicity of RV-HIV viruses used as a prime or boost for DNA or NYVAC candidates was compared to a DNA prime/NYVAC boost benchmark scheme when administered together with adjuvanted gp120 protein. Similar neutralizing antibody titers, binding IgG titers measured against a broad panel of Env and Gag antigens, and ADCC responses were observed in the groups throughout the course of the study, and T cell responses were elicited. The entire data demonstrate that RV vectors have the potential as novel HIV-1 vaccine components for use in combination with other promising candidates to develop new effective vaccination strategies.
Results are presented from measuring the
cross section and effective neutron timelike form factor. Data are collected in 2020–2021 at the VEPP-2000
collider in the 1891 to 2007 MeV center-of-mass ...range of energies. The general purpose nonmagnetic SND detector is used to detect neutron–antineutron events. The time-of-flight approach is used to select
events. The measured cross section is 0.4–0.6 nbn. The neutron form factor in the investigated range of energies varies from 0.3 to 0.2.
Chemistry of pyridoxine in drug design Shtyrlin, Y. G.; Petukhov, A. S.; Strelnik, A. D. ...
Russian chemical bulletin,
05/2019, Letnik:
68, Številka:
5
Journal Article
Recenzirano
Pyridoxine and its derivatives, pyridoxamine and pyridoxal, are the three main forms of vitamin B
6
, which play exceptionally important biological roles in living organisms. The active endogenous ...metabolites of these molecules, pyridoxal phosphate and pyridoxamine phosphate, are the most important coenzymes involved in a wide range of biochemical reactions necessary for cell activity, due to which pyridoxine and its derivatives are regarded as biologically privileged molecules. Taking into account also the wide possibilities for chemical modification of the pyridoxine structure, it is only natural for medicinal chemists to explore them in the design of novel drugs. This review summarizes the data on the main pharmacologically significant pyridoxine derivatives (including pyridoxamine and pyridoxal derivatives) reported in modern scientifi c and patent sources. Methods for their synthesis, key pharmacological properties, and medicinal chemistry concepts underlying the design of the developing physiologically active compounds are presented. The promising directions for future development of chemistry of physiologically active pyridoxine derivatives are also discussed.
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