RESUMEN
The neutron inelastic scattering of carbon-12, populating the Hoyle state, is a reaction of interest for the triple-alpha process. The inverse process (neutron upscattering) can enhance the Hoyle state's decay rate to the bound states of 12C, effectively increasing the overall triple-alpha reaction rate. The cross section of this reaction is impossible to measure experimentally but has been determined here at astrophysically-relevant energies using detailed balance. Using a highly-collimated monoenergetic beam, here we measure neutrons incident on the Texas Active Target Time Projection Chamber (TexAT TPC) filled with CO2 gas, we measure the 3α-particles (arising from the decay of the Hoyle state following inelastic scattering) and a cross section is extracted. Here we show the neutron-upscattering enhancement is observed to be much smaller than previously expected. The importance of the neutron-upscattering enhancement may therefore not be significant aside from in very particular astrophysical sites (e.g. neutron star mergers).
Asunto(s)
Procedimientos Endovasculares/métodos , Recuperación de la Función , Obstrucción de la Arteria Renal/cirugía , Arteria Renal/fisiopatología , Circulación Renal/fisiología , Stents , Angiografía , Enfermedad Crónica , Humanos , Masculino , Persona de Mediana Edad , Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/diagnóstico , Obstrucción de la Arteria Renal/fisiopatología , Ultrasonografía DopplerRESUMEN
The authors analyzed a condition of coronary collateral circulation in infarction-related artery in patients with acute myocardial infarction with rise and without rise of ST segment. The assessment of collateral circulation was made by coronary angiography using Rentop scale. Results of the research showed, that collateral circulation wasn't visualized by angiography in the first hours after acute myocardial infarction with the rise of ST segment. Apparently, this circulation didn't significantly assisted in maintenance of vital capacity of the myocardium in the pool of infarction-related occlusive coronary artery. Visualization of collateral circulation was noted in majority of patients with acute myocardial infarction without the rise of ST segment. Collateral flow was an important alternative source of blood supply of the heart in patients without rise of ST segment in the period of critical reduction of the antegrade blood flow.
Asunto(s)
Circulación Colateral , Vasos Coronarios , Reserva del Flujo Fraccional Miocárdico , Anciano , Angiografía Coronaria/métodos , Vasos Coronarios/patología , Vasos Coronarios/fisiopatología , Electrocardiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/fisiopatología , Proyectos de Investigación , Estadística como Asunto , Factores de TiempoRESUMEN
The article analyzed no-reflow phenomenon after endovascular recanalization for chronic coronary occlusion. An assessment of antegrade blood flow was made while performing the coronary angiography according to TIMI classification. The Rentrop scale was used for evaluation of retrograde blood flow. The results of investigation showed, that the frequency of occurrence of no-reflow phenomenon after endovascular recanalization in the case of chronic coronary occlusion wasn't higher than 5%. The onset of no-reflow phenomenon after endovascular recanalization in chronic coronary occlusion doesn't depend on the volume of retrograde collateral filling of distal coronary bloodstream. A postponed restoration of antegrade blood flow was possible in patients with previously manifested (Rentrop II-III) retrograde collateral filling of periphery.
Asunto(s)
Angioplastia Coronaria con Balón , Oclusión Coronaria , Fenómeno de no Reflujo , Angioplastia Coronaria con Balón/efectos adversos , Angioplastia Coronaria con Balón/métodos , Enfermedad Crónica , Angiografía Coronaria/métodos , Circulación Coronaria , Oclusión Coronaria/diagnóstico , Oclusión Coronaria/fisiopatología , Oclusión Coronaria/cirugía , Femenino , Humanos , Masculino , Microvasos/fisiopatología , Persona de Mediana Edad , Fenómeno de no Reflujo/etiología , Fenómeno de no Reflujo/fisiopatología , Stents , Resultado del TratamientoRESUMEN
The γ-ray strength function of 56Fe has been measured from proton-γ coincidences for excitation energies up to ≈11 MeV. The low-energy enhancement in the γ-ray strength function, which was first discovered in the (3He,αγ)56Fe reaction, is confirmed with the (p,p'γ)56Fe experiment reported here. Angular distributions of the γ rays give for the first time evidence that the enhancement is dominated by dipole transitions.
Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Angiopatías Diabéticas/complicaciones , Pie Diabético , Neuropatías Diabéticas/complicaciones , Amputación Quirúrgica/métodos , Amputación Quirúrgica/estadística & datos numéricos , Diabetes Mellitus Tipo 2/metabolismo , Angiopatías Diabéticas/metabolismo , Angiopatías Diabéticas/fisiopatología , Pie Diabético/diagnóstico , Pie Diabético/etiología , Pie Diabético/metabolismo , Pie Diabético/mortalidad , Pie Diabético/fisiopatología , Pie Diabético/terapia , Neuropatías Diabéticas/metabolismo , Neuropatías Diabéticas/fisiopatología , Pie/irrigación sanguínea , Pie/cirugía , Humanos , Microvasos/metabolismo , Microvasos/fisiopatología , Plasmaféresis/métodos , PronósticoRESUMEN
Experimental and morphological studies demonstrated that Gore Resolute resorbable membrane can cause local inflammatory reactions similar to allergic. Collagen-based biomembranes coated with hydroxyapatite cause no local pathological reactions, but are rapidly resorbed in foci of degeneration under the effect of aggressive factors of tissue environment. Russian silicone membrane has been clinically tried with satisfactory results in patients with generalized periodontitis; the results prompt further studies of the membrane.
Asunto(s)
Materiales Biocompatibles , Inflamación/etiología , Membranas Artificiales , Enfermedades Periodontales/terapia , Materiales Biocompatibles/efectos adversos , Humanos , Resultado del TratamientoRESUMEN
Although radiotherapy is known to improve the results of treatment for pancreatic carcinoma, its application is limited due to such side effects and complications as anemia, leuko-, thrombocytopenia and dyspeptic disorders. It was suggested that since these complications are primarily caused by radiotherapy itself and mass death of tumor cells, plasmapheresis might raise tolerance to radiation. This was confirmed by our experience with its use during radiotherapy course in 22 patients with pancreatic cancer.
Asunto(s)
Enfermedades Hematológicas/etiología , Enfermedades Hematológicas/terapia , Neoplasias Pancreáticas/radioterapia , Plasmaféresis , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Enfermedades Hematológicas/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Radioterapia Adyuvante/efectos adversos , Resultado del TratamientoRESUMEN
Time course of healing of standard osseous defects by introduction of polyacrylamide gel (PAG)-based materials was studied in rat experiments. PAG did not prevent the formation of soft-tissue and osseous regenerate in bone defects. Addition of hydroxyapatite, bactericidal agent, and lysozyme to PAG-based composition led in some cases to development of chronic inflammation and giant-cell reaction in osseous wound and to inhibition of the reparative processes.