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1.
Phys Rev Lett ; 128(25): 252701, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35802450

RESUMEN

The anomaly in lithium abundance is a well-known unresolved problem in nuclear astrophysics. A recent revisit to the problem tried the avenue of resonance enhancement to account for the primordial ^{7}Li abundance in standard big-bang nucleosynthesis. Prior measurements of the ^{7}Be(d,p)^{8}Be^{*} reaction could not account for the individual contributions of the different excited states involved, particularly at higher energies close to the Q value of the reaction. We carried out an experiment at HIE-ISOLDE, CERN to study this reaction at E_{c.m.}=7.8 MeV, populating excitations up to 22 MeV in ^{8}Be for the first time. The angular distributions of the several excited states have been measured and the contributions of the higher excited states in the total cross section at the relevant big-bang energies were obtained by extrapolation to the Gamow window using the talys code. The results show that by including the contribution of the 16.63 MeV state, the maximum value of the total S factor inside the Gamow window comes out to be 167 MeV b as compared to earlier estimate of 100 MeV b. However, this still does not account for the lithium discrepancy.

2.
Khirurgiia (Mosk) ; (11): 39-46, 2021.
Artículo en Ruso | MEDLINE | ID: mdl-34786915

RESUMEN

OBJECTIVE: To increase an efficiency of surgical treatment of bronchopleural complications after lung resections and pleurectomies through the development of modern indications, treatment strategies, techniques and postoperative management. MATERIAL AND METHODS: We analyzed data in 252 patients with bronchopleural complications after lung resections and pleurectomies. The study included patients who underwent treatment at the Central Research Institute of Tuberculosis for the period 2004-2010, Clinical Hospital of Phthisiopulmonology of the Sechenov First Moscow State Medical University for the period 2011-2017 and Thoracic Center of the Republic of Ingushetia for the period 2015-2019. The study included patients with postoperative pleural empyema divided into two groups: group I - 138 patients with empyema and bronchial fistula; group II - 114 patients with empyema and no bronchial fistula. In the 1st group, 1 patient had bronchial and esophageal fistulas. RESULTS: At discharge, empyema and bronchial fistula were eliminated in 245 (97.2%) patients of both groups. Overall in-hospital mortality was 1.6% (4 cases). Two (1.4%) patients died within 30 days in group I and 1 (0.9%) patient died in group II. Within 90 days after surgery, another patient died from acute cerebrovascular accident in group I. In long-term period, overall effectiveness of treatment of bronchopleural complications was 97.2% (208 out of 214 cases). CONCLUSION: The original surgical approach for bronchopleural complications considers timing of postoperative empyema, its spread and duration. This method together with minimally invasive interventions reduces mortality and ensures stable recovery after bronchopleural complications in 97.2% of patients.


Asunto(s)
Fístula Bronquial , Empiema Pleural , Enfermedades Pleurales , Tuberculosis , Bronquios , Fístula Bronquial/diagnóstico , Fístula Bronquial/etiología , Fístula Bronquial/cirugía , Empiema Pleural/diagnóstico , Empiema Pleural/etiología , Empiema Pleural/cirugía , Humanos , Enfermedades Pleurales/diagnóstico , Enfermedades Pleurales/etiología , Enfermedades Pleurales/cirugía
3.
Phys Rev Lett ; 124(6): 062502, 2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32109128

RESUMEN

The nuclei below lead but with more than 126 neutrons are crucial to an understanding of the astrophysical r process in producing nuclei heavier than A∼190. Despite their importance, the structure and properties of these nuclei remain experimentally untested as they are difficult to produce in nuclear reactions with stable beams. In a first exploration of the shell structure of this region, neutron excitations in ^{207}Hg have been probed using the neutron-adding (d,p) reaction in inverse kinematics. The radioactive beam of ^{206}Hg was delivered to the new ISOLDE Solenoidal Spectrometer at an energy above the Coulomb barrier. The spectroscopy of ^{207}Hg marks a first step in improving our understanding of the relevant structural properties of nuclei involved in a key part of the path of the r process.

4.
Phys Rev Lett ; 124(2): 022501, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-32004026

RESUMEN

Spectroscopic factors of neutron-hole and proton-hole states in ^{131}Sn and ^{131}In, respectively, were measured using one-nucleon removal reactions from doubly magic ^{132}Sn at relativistic energies. For ^{131}In, a 2910(50)-keV γ ray was observed for the first time and tentatively assigned to a decay from a 5/2^{-} state at 3275(50) keV to the known 1/2^{-} level at 365 keV. The spectroscopic factors determined for this new excited state and three other single-hole states provide first evidence for a strong fragmentation of single-hole strength in ^{131}Sn and ^{131}In. The experimental results are compared to theoretical calculations based on the relativistic particle-vibration coupling model and to experimental information for single-hole states in the stable doubly magic nucleus ^{208}Pb.

5.
Phys Rev Lett ; 123(9): 092502, 2019 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-31524489

RESUMEN

The most remote isotope from the proton dripline (by 4 atomic mass units) has been observed: ^{31}K. It is unbound with respect to three-proton (3p) emission, and its decays have been detected in flight by measuring the trajectories of all decay products using microstrip detectors. The 3p emission processes have been studied by the means of angular correlations of ^{28}S+3p and the respective decay vertices. The energies of the previously unknown ground and excited states of ^{31}K have been determined. This provides its 3p separation energy value S_{3p} of -4.6(2) MeV. Upper half-life limits of 10 ps of the observed ^{31}K states have been derived from distributions of the measured decay vertices.

6.
Khirurgiia (Mosk) ; (8): 22-28, 2019.
Artículo en Ruso | MEDLINE | ID: mdl-31464270

RESUMEN

OBJECTIVE: To analyze surgical treatment of tuberculous pleural empyema in children depending on the stage of the process. MATERIAL AND METHODS: There were 82 patients aged 4-17 years with tuberculous pleural empyema. Clinical and X-ray features of different stages of disease are described. Certain types of surgical interventions at each stage of the process are analyzed. RESULTS: In 72 children with empyema stage III 76 surgeries were performed. Postoperative complications occurred in 2 (2.6%) cases (delayed lung inflation) that required thoracocentesis with pleural drainage. There was no postoperative mortality. CONCLUSION: Complex treatment of tuberculous pleural empyema in children and adolescents with the use of modern surgical methods is followed by satisfactory outcomes in all patients. However, surgical technique, postoperative morbidity and hospital-stay depend on the stage of the process. Unfortunately, almost 90% of patients had empyema stage III. Therefore, minimally invasive surgery was not advisable and extensive, traumatic surgeries were required.


Asunto(s)
Empiema Tuberculoso/cirugía , Adolescente , Niño , Preescolar , Drenaje , Empiema Tuberculoso/diagnóstico por imagen , Humanos , Pleura/cirugía , Toracocentesis
8.
Phys Rev Lett ; 118(15): 152502, 2017 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-28452556

RESUMEN

Angular distributions of the elastic, inelastic, and breakup cross sections of the halo nucleus ^{11}Be on ^{197}Au were measured at energies below (E_{lab}=31.9 MeV) and around (39.6 MeV) the Coulomb barrier. These three channels were unambiguously separated for the first time for reactions of ^{11}Be on a high-Z target at low energies. The experiment was performed at TRIUMF (Vancouver, Canada). The differential cross sections were compared with three different calculations: semiclassical, inert-core continuum-coupled-channels and continuum-coupled-channels ones with including core deformation. These results show conclusively that the elastic and inelastic differential cross sections can only be accounted for if core-excited admixtures are taken into account. The cross sections for these channels strongly depend on the B(E1) distribution in ^{11}Be, and the reaction mechanism is sensitive to the entanglement of core and halo degrees of freedom in ^{11}Be.

9.
Phys Rev Lett ; 115(20): 202501, 2015 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-26613434

RESUMEN

Previously unknown isotopes (30)Ar and (29)Cl have been identified by measurement of the trajectories of their in-flight decay products (28)S+p+p and (28)S+p, respectively. The analysis of angular correlations of the fragments provided information on decay energies and the structure of the parent states. The ground states of (30)Ar and (29)Cl were found at 2.25(-0.10)(+0.15) and 1.8±0.1 MeV above the two- and one-proton thresholds, respectively. The lowest states in (30)Ar and (29)Cl point to a violation of isobaric symmetry in the structure of these unbound nuclei. The two-proton decay has been identified in a transition region between simultaneous two-proton and sequential proton emissions from the (30)Ar ground state, which is characterized by an interplay of three-body and two-body decay mechanisms. The first hint of a fine structure of the two-proton decay of (30)Ar*(2(+)) has been obtained by detecting two decay branches into the ground and first-excited states of the (28)S fragment.

10.
Khirurgiia (Mosk) ; (9): 35-42, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26762076

RESUMEN

AIM: To improve the efficiency of treatment of single lung destructive tuberculosis. MATERIAL AND METHODS: 15-year experience of operations for destructive tuberculosis performed by the same surgeon including 18 resections of the single lung and 19 pneumonectomies after previous partial lung resection is presented in the article. RESULTS: Surgical management of patients with destructive tuberculosis of single lung provides positive results in more than 90% of cases. However the frequency of its application is still low according to literature data. In case of destructive tuberculosis of single lung partial resection is more frequently indicated if fibrous-cavernous tuberculosis of the upper lung (up to 4 damaged segments), persistent bacterial excretion on the background of adequate chemotherapy and pathogen's drug resistance are present.


Asunto(s)
Pulmón/cirugía , Neumonectomía/métodos , Cirugía Torácica Asistida por Video/métodos , Tuberculosis Pulmonar/cirugía , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reoperación , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Tuberculosis Pulmonar/diagnóstico , Adulto Joven
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