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1.
Phys Rev Lett ; 132(2): 021001, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38277596

RESUMO

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

2.
Phys Rev Lett ; 130(6): 061001, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827568

RESUMO

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

3.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929235

RESUMO

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

4.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016715

RESUMO

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.

5.
Med Parazitol (Mosk) ; (2): 37-42, 2017 Apr.
Artigo em Russo | MEDLINE | ID: mdl-30721601

RESUMO

West Nile fever (WNF) is a natural focal vector-borne disease; the main vectors are mosquitoes. Specific means for its prevention are not available; therefore, one of the main areas of WNF epidemiological surveillance is entomological monitoring that encompasses the control of the size ofvector populations arid the determination of infection rate of mos- quitoes with the virus in order to predict the epidemic situation. An analysis of normative documents on the collection and control of mosquito populations showed it necessary to improve entomological monitoring. Based on the literary and their own data, the authors propose to catch only Culix mosquitoes in the foci of WNF and to analyze their infection rates. The mosquitoes should be caught in mid-June to mid-September in the stationary points of urban and rural biotopes once every 7-10 days, by using automatic traps with CO2 as an attractant. At least 500 specimens should be examined for virus RNA by PCR every 7-10 days to predict the epidemic situation.


Assuntos
Monitoramento Epidemiológico , Mosquitos Vetores/virologia , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/patogenicidade , Animais , Humanos , Mosquitos Vetores/patogenicidade , Densidade Demográfica , Federação Russa/epidemiologia , Febre do Nilo Ocidental/virologia
6.
Phys Rev Lett ; 117(19): 192001, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27858429

RESUMO

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.

7.
Phys Rev Lett ; 116(24): 241101, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27367377

RESUMO

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8±0.7(stat)±6.7(syst) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.

8.
Eur Phys J C Part Fields ; 75(6): 269, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26120280

RESUMO

Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with [Formula: see text] eV by analyzing cosmic rays with energies above [Formula: see text] eV arriving within an angular separation of approximately 15[Formula: see text]. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.

9.
Med Parazitol (Mosk) ; (1): 14-9, 2015.
Artigo em Russo | MEDLINE | ID: mdl-25850309

RESUMO

The infection of Culex pipiens f. pipiens and Cx. pipiens f. molestus mosquitoes with Western Nile virus was studied. Their taxonomic status was determined from the type of mitochondrial DNA. Among 424 females individually examined, there were 4 infected specimens: 3 pipens females gathered in the urban and suburban open biotopes and one molestus female caught in the open urban biotope. Molestus mitotype females were first detected in the suburban open biotopes. The possible reasons for the wide colonization of molestus mosquitoes and its epidemic consequences are discussed.


Assuntos
Culex/genética , Culex/virologia , DNA Mitocondrial/genética , Planejamento Social , Reforma Urbana , Vírus do Nilo Ocidental , Animais , Feminino , Masculino , Federação Russa
10.
Klin Khir ; (10): 37-9, 2014 Oct.
Artigo em Ucraniano | MEDLINE | ID: mdl-25675785

RESUMO

Surgical treatment of 80 patients, suffering mammary gland cancer (MGC), was conducted. The complications rate in elderly and young patients after radical surgical treatment was analyzed. There was established, that while preparation Traumastem P application in elderly patients, suffering MGC, the lymphorrhea volume and duration are reducing, what prevents complications in postoperative period.


Assuntos
Neoplasias da Mama/cirurgia , Hemostáticos/uso terapêutico , Linfedema/prevenção & controle , Glândulas Mamárias Humanas/cirurgia , Necrose/prevenção & controle , Complicações Pós-Operatórias , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Humanos , Linfedema/patologia , Glândulas Mamárias Humanas/patologia , Pessoa de Meia-Idade , Necrose/patologia
11.
Tsitol Genet ; 34(1): 10-4, 2000.
Artigo em Ucraniano | MEDLINE | ID: mdl-10808536

RESUMO

Investigation was carried out on the epithelial cells obtained from 32 patients with benign and malignant tumors of large intestine aged from 42 to 80 years. Ratio of single-stranded and double-stranded DNAs in the epithelial cells of unchanged colorectal mucosa (12 patterns), adenomatous polyps (4) and adenocarcinomas (29) was studied using fluorimetric analysis. Increased instability of DNA secondary structure was revealed in the tumor cells comparing to the cells of unchanged colorectal epithelium. Relative accumulation of single-stranded DNA reflects structural and functional changes in gene apparatus of cells under malignization.


Assuntos
Adenocarcinoma/genética , DNA de Neoplasias/química , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/metabolismo , Intestino Grosso/metabolismo , Conformação de Ácido Nucleico , Pólipos Adenomatosos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA/metabolismo , DNA de Neoplasias/metabolismo , DNA de Cadeia Simples/metabolismo , Células Epiteliais/metabolismo , Citometria de Fluxo/métodos , Humanos , Pessoa de Meia-Idade
12.
Tsitol Genet ; 33(3): 27-33, 1999.
Artigo em Ucraniano | MEDLINE | ID: mdl-10474860

RESUMO

Cytospectrophotometric analysis of DNA content in nuclei of the epithelial cells in fibroadenoma, fibroadenomatous and breast cancer revealed that mean value of DNA content in breast cancer is reliably higher than in benign processes in breast. Modal class in fibroadenoma and fibroadenomatous formed by di- and tetraploid cells, in breast cancer-tetraploid and higher depending on histological structure of tumor. Ratio of aneuploidy is higher in invasive ductal carcinoma and scirrhus [correction of skir] in comparison with invasive lobular carcinoma and other carcinomas, that evidences higher aggressiveness of these tumors.


Assuntos
Adenocarcinoma Esquirroso/química , Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , DNA de Neoplasias/análise , Fibroadenoma/química , Adenocarcinoma Esquirroso/diagnóstico , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Núcleo Celular/química , Citofotometria , Diagnóstico Diferencial , Feminino , Fibroadenoma/diagnóstico , Humanos , Pessoa de Meia-Idade , Ploidias , Espectrofotometria
14.
Tsitol Genet ; 32(2): 80-7, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9783368

RESUMO

The DNA content in epitheliocytes of the mucous membrane of the oral cavity and expression of carcinoembryonic antigen and trophoblast-specific beta-1 glycoprotein on peripheral blood lymphocytes, peripheral blood T-lymphocytes subsets into three groups of patients: 1--diffusion mastopathy; 2--diffusion mastopathy with fibromyoma uteri and 3--fibroadenoma were studied. It was indicated that DNA content was higher in all groups in comparison with healthy women and it was shown that in contrast to healthy women, 45% of patients studied had abnormal rate of T-cells subsets, about 30% of them had abnormal expression of CEA and TSG on peripheral blood lymphocytes. The data obtained show the significant disbalance in the mechanisms of defence and compensation taking place in the organisms of patients with nonmalignant mammary diseases.


Assuntos
Antígenos de Neoplasias/sangue , DNA de Neoplasias/análise , DNA/análise , Doença da Mama Fibrocística/genética , Doença da Mama Fibrocística/imunologia , Mucosa Bucal/química , Linfócitos T/imunologia , Adulto , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Células Epiteliais/química , Feminino , Fibroadenoma/genética , Fibroadenoma/imunologia , Humanos , Leiomioma/genética , Leiomioma/imunologia , Contagem de Linfócitos , Pessoa de Meia-Idade , Neoplasias Uterinas/genética , Neoplasias Uterinas/imunologia
15.
Tsitol Genet ; 32(1): 49-55, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9695252

RESUMO

During the malignant progression changes occur in the composition and content of carbohydrates in the cellular membrane. We studied distribution of lectin receptors SBA, PNA, WGA and HPA in dysplasias and human breast cancer. We established that malignancy is associated with the increase in mosaic staining and shift of lectin receptors from the apical or basal pole of acinar epithelium and ducts to the whole plasmolemma surface, homogeneous staining of cytoplasm and nuclei of tumor cells. It is evident that distribution of lectines in dysplasias and malignant mammary tumors may serve a diagnostic marker and indicator in predicting metastatic potential.


Assuntos
Neoplasias da Mama/metabolismo , Doença da Mama Fibrocística/metabolismo , Lectinas/metabolismo , Adulto , Idoso , Biomarcadores , Mama/metabolismo , Neoplasias da Mama/diagnóstico , Feminino , Doença da Mama Fibrocística/diagnóstico , Histocitoquímica , Humanos , Pessoa de Meia-Idade , Receptores Mitogênicos/metabolismo , Coloração e Rotulagem/métodos
16.
Tsitol Genet ; 29(5): 60-4, 1995.
Artigo em Russo | MEDLINE | ID: mdl-8721848

RESUMO

Complex clinical-genealogical and genetic study of 261 patients with breast cancer (BC) was carried out in Kiev region. It was demonstrated that the multifactorial origin of BC was of first importance in this population. The share of genetic component in the susceptibility to BC comprise 55.68 +/- 2.44%. Risk of the origin of malignant tumors in progeny was calculated.


Assuntos
Alelos , Neoplasias da Mama/genética , Variação Genética/genética , População Urbana , Feminino , Técnicas Genéticas , Genótipo , Humanos , Linhagem , Fenótipo , Software , Ucrânia
17.
Tsitol Genet ; 28(1): 73-6, 1994.
Artigo em Russo | MEDLINE | ID: mdl-8066818

RESUMO

Patients with malignant melanomas and breast cancer (83 men and women) were examined. On the basis of study of the DNA contents in nuclei of epitheliocytes from the mucous oral cavity, index of their nuclei heterogeneity we have revealed disturbances in maturation and differentiation of cells. They were arranged to the spinous layer of the oral mucosa. The disturbances were caused by the tumour influence on the functional state of the mucosa.


Assuntos
Neoplasias da Mama/química , DNA/análise , Melanoma/química , Mucosa Bucal/química , Neoplasias Cutâneas/química , Adulto , Diferenciação Celular , Núcleo Celular/química , Bochecha , Células Epiteliais , Epitélio/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/citologia , Periodonto/química , Espectrofotometria
18.
Tsitol Genet ; 25(5): 9-11, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1796515

RESUMO

The results obtained have permitted establishing that changes of DNA content in epitheliocyte nuclei in practically healthy people can be induced by hormonal background in the organism, on the one hand, and by the level of cell differentiation in this globe of mucous membrane of the oral cavity, on the other hand.


Assuntos
DNA/análise , Mucosa Bucal/química , Diferenciação Celular/fisiologia , Núcleo Celular/química , Bochecha , Epitélio/química , Feminino , Hormônios/fisiologia , Humanos , Masculino , Valores de Referência
20.
Vopr Onkol ; 25(12): 36-40, 1979.
Artigo em Russo | MEDLINE | ID: mdl-516582

RESUMO

Experimentally, on the Biskind model it was shown that the development of ovarian tumors transplanted into the spleen is proceded by a progressive reduction in the amount of active splenic cell elements, containing serotonin and hydrolytic enzymes, and by the increased changes in the structure and chemical composition of non-cellular elements of its connective tissue framework with catecholamines accumulated in the latter and the remaining cells. The injection of anticollagen serum (ACS) would increase the terms of tumors arising with the resultant predominance of their benign forms.


Assuntos
Anticorpos/administração & dosagem , Colágeno/imunologia , Transplante de Neoplasias , Neoplasias Ovarianas/patologia , Baço , Animais , Feminino , Hidrolases/metabolismo , Neoplasias Experimentais/patologia , Ratos , Baço/efeitos dos fármacos , Baço/enzimologia , Baço/patologia
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