27 research outputs found
First atom lifetime and scattering length measurements
The results of a search for hydrogen-like atoms consisting of
mesons are presented. Evidence for atom production
by 24 GeV/c protons from CERN PS interacting with a nickel target has been seen
in terms of characteristic pairs from their breakup in the same target
() and from Coulomb final state interaction (). Using
these results the analysis yields a first value for the atom lifetime
of fs and a first model-independent measurement of
the S-wave isospin-odd scattering length
( for isospin ).Comment: 14 pages, 8 figure
Investigation of pairs in the effective mass region near
The DIRAC experiment at CERN investigated in the reaction
the particle pairs and with relative momentum in the pair system less than 100 MeV/c.
Because of background influence studies, DIRAC explored three subsamples of
pairs, obtained by subtracting -- using time-of-flight (TOF) technique
-- background from initial distributions with sample fractions
more than 70\%, 50\% and 30\%. The corresponding pair distributions in and
in its longitudinal projection were analyzed first in a Coulomb model,
which takes into account only Coulomb final state interaction (FSI) and
assuming point-like pair production. This Coulomb model analysis leads to a
yield increase of about four at MeV/c compared to 100 MeV/c.
In order to study contributions from strong interaction, a second more
sophisticated model was applied, considering besides Coulomb FSI also strong
FSI via the resonances and and a variable distance
between the produced mesons. This analysis was based on three different
parameter sets for the pair production. For the 70\% subsample and with best
parameters, pairs was found to be compared to extracted by means of the Coulomb model. Knowing the efficiency
of the TOF cut for background suppression, the total number of detected
pairs was evaluated to be around , which agrees with
the result from the 30\% subsample. The pair number in the 50\%
subsample differs from the two other values by about three standard deviations,
confirming -- as discussed in the paper -- that experimental data in this
subsample is less reliable
Evidence for -atoms with DIRAC
We present evidence for the first observation of electromagnetically bound
-pairs (-atoms) with the DIRAC experiment at the CERN-PS.
The -atoms are produced by the 24 GeV/c proton beam in a thin Pt-target
and the and -mesons from the atom dissociation are analyzed in
a two-arm magnetic spectrometer. The observed enhancement at low relative
momentum corresponds to the production of 173 54 -atoms. The mean
life of -atoms is related to the s-wave -scattering lengths, the
measurement of which is the goal of the experiment. From these first data we
derive a lower limit for the mean life of 0.8 fs at 90% confidence level.Comment: 15 pages, 9 figure
Discovery of potential ovarian cancer biomarkers using low molecular weight blood plasma proteome profiling by mass spectrometry
At present, there is no screening test for the early detecting and monitoring of ovarian cancer, one of the most lethal form of gynaecological malig- nancy in the worldwide. In this study, the new methodology for the search of tumor markers of ovarian cancer, involving profiling the low-molec- ular blood plasma proteomes, is developed, unified and approved. The given approach included three basic components: pre-preparation of samples, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and bioinformatics software for mass spectral data process- ing. Opportunities and prospects of the developed approach for the detection of potential ovarian cancer markers were shown. For search of po- tential tumor markers, screening of 40 blood plasma samples from ovarian cancer patients and 48 control samples were carried out. As a result of the present research, peptides/polypeptides which can be used in future for detecting this pathology were found out
Use of cellular biotechnologies in treatment metastatic pericarditis at patients with tumors of female reproductive system
Malignant pericardial effusions often arise in patients with breаst cancer and ovarian cancer. Sistem antitumor therapy is uneffective in gen- erally and causes side effects. Here we show that intrapericardial interleukin-2 with allogenеc lymphokine-activated killers and interleukin-2 immunotherapy demonstrated the high efficacy in threatment of breаst and ovarian cancer patients with malignant pericardial effusions. The objective effect was 92.3 % аnd 90.0 % accordingly. These results indicates that intrapericardial immunotherapy might be one of the stages of combined treatment of such group of patients. The suggested type of biotherapy increases the survival and life quality of patients
Imunotherapy opportunities in ovarian cancer
In the last decade, accumulated evidence in favor of that ovarian cancer is an immunogenic tumor. Immunotherapy is aimed at stimulating the innate and adaptive immunity, may cause an effective response in patients with ovarian cancer. Various approaches immunotherapy include cytokinetherapy, use of monoclonal antibodies and cell therapy
The Level of Meningococcal Carriage and Genotyping of N. meningitidis Strains in the Group of Labor Migrants
Relevance. Population migration can play a crucial role in the spread of invasive strains of meningococcus, initiating outbreaks of meningococcal infection, and changing the incidence at the local level.Aim. To assess the prevalence of meningococcal carriage among migrants arriving in Moscow and to characterize the antigenic and genetic properties of carrier strains of meningococcus.Materials and methods. The study was conducted in March 2020 at the bases of the Multifunctional Migration Center of Moscow and the Federal Budget Institution of Science «Central Research Institute of Epidemiology». Samples of nasopharyngeal mucus were collected from 352 people. Nasopharyngeal strains of meningococcus were identified and identified using microbiological, serological, and molecular biological methods.Results. The overall level of the carriage was 5.7%. Of the twenty selected strains, 10 have a serogroup defined: Y – 5 strains, W - 3, A, and B – 1 each. The obtained genetic and antigenic characteristics do not allow talking about the import into the RF of representatives of known hypervirulent clonal complexes. In this study, strains were identified that are part of the clonal complex ST-175 complex, which has not been previously described in the Russian Federation.Conclusion. It seems promising to continue the dynamic monitoring of carriage of meningococcus in various groups, including among people entering the country to obtain a migration patent, as well as identifying risk factors for acquiring carriage. The data obtained will supplement current information on the incidence of the generalized form of meningococcal infection and will be crucial for determining the epidemiology at the country level, the population groups responsible for the transmission of the disease, and the need for targeted vaccination