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1.
Phys Rev Lett ; 131(17): 172501, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955509

RESUMEN

The boundaries of the chart of nuclides contain exotic isotopes that possess extreme proton-to-neutron asymmetries. Here we report on strong evidence of ^{9}N, one of the most exotic proton-rich isotopes where more than one half of its constitute nucleons are unbound. With seven protons and two neutrons, this extremely proton-rich system would represent the first-known example of a ground-state five-proton emitter. The invariant-mass spectrum of its decay products can be fit with two peaks whose energies are consistent with the theoretical predictions of an open-quantum-system approach; however, we cannot rule out the possibility that only a single resonancelike peak is present in the spectrum.

2.
Actas Dermosifiliogr ; 114(6): 479-487, 2023 Jun.
Artículo en Inglés, Español | MEDLINE | ID: mdl-36935039

RESUMEN

BACKGROUND: In recent years, remarkable improvements in our understanding of atopic dermatitis (AD) have revolutionized treatment perspectives, but access to reliable data from clinical practice is essential. MATERIALS AND METHOD: The Spanish Atopic Dermatitis Registry, BIOBADATOP, is a prospective, multicenter database that collects information on patients of all ages with AD requiring systemic therapy with conventional or novel drugs. We analyzed the registry to describe patient characteristics, diagnoses, treatments, and adverse events (AEs). RESULTS: We studied data entries for 258 patients who had received 347 systemic treatments for AD. Treatment was discontinued in 29.4% of cases, mostly due to a lack of effectiveness (in 10.7% of cases). A total of 132 AEs were described during follow-up. Eighty-six AEs (65%) were linked to a systemic treatment, most commonly dupilumab (39AEs) and cyclosporine (38AEs). The most common AEs were conjunctivitis (11patients), headache (6), hypertrichosis (5), and nausea (4). There was 1severe AE (acute mastoiditis) associated with cyclosporine. CONCLUSIONS: Initial findings on AEs from the Spanish BIOBADATOP registry are limited by short follow-up times precluding comparisons or calculation of crude and adjusted incidence rates. At the time of our analysis, no severe AEs had been reported for novel systemic therapies. BIOBADATOP will help answer questions on the effectiveness and safety of conventional and novel systemic therapies in AD.


Asunto(s)
Dermatitis Atópica , Humanos , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/epidemiología , Estudios Prospectivos , Ciclosporina/uso terapéutico , Administración Cutánea , Sistema de Registros , Resultado del Tratamiento , Índice de Severidad de la Enfermedad
3.
Phys Rev Lett ; 129(1): 012501, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35841541

RESUMEN

A narrow near-threshold proton-emitting resonance (E_{x}=11.4 MeV, J^{π}=1/2^{+}, and Γ_{p}=4.4 keV) was directly observed in ^{11}B via proton resonance scattering. This resonance was previously inferred in the ß-delayed proton emission of the neutron halo nucleus ^{11}Be. The good agreement between both experimental results serves as a ground to confirm the existence of such exotic decay and the particular behavior of weakly bound nuclei coupled to the continuum. R-matrix analysis shows a sizable partial decay width for both, proton and α (Γ_{α}=11 keV) emission channels.

4.
Rev Sci Instrum ; 92(6): 063302, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243507

RESUMEN

The Superconducting Analyzer for MUlti-particles from RAdioIsotope (SAMURAI) Pion-Reconstruction and Ion-Tracker Time Projection Chamber (SπRIT TPC) was designed to enable measurements of heavy ion collisions with the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory and provides constraints on the equation of state of neutron-rich nuclear matter. The SπRIT TPC has a 50.5 cm drift length and an 86.4 × 134.4 cm2 pad plane with 12 096 pads that are equipped with the generic electronics for TPCs. The SπRIT TPC allows for an excellent reconstruction of particles and provides isotopic resolution for pions and other light charged particles across a wide range of energy losses and momenta. The details of the SπRIT TPC are presented, along with discussion of the TPC performance based on cosmic rays and charged particles emitted in heavy ion collisions.

5.
Phys Rev Lett ; 126(16): 162701, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33961456

RESUMEN

Many neutron star properties, such as the proton fraction, reflect the symmetry energy contributions to the equation of state that dominate when neutron and proton densities differ strongly. To constrain these contributions at suprasaturation densities, we measure the spectra of charged pions produced by colliding rare isotope tin (Sn) beams with isotopically enriched Sn targets. Using ratios of the charged pion spectra measured at high transverse momenta, we deduce the slope of the symmetry energy to be 42

6.
Phys Rev Lett ; 126(13): 132501, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33861136

RESUMEN

A ^{13}F resonance was observed following a charge-exchange reaction between a fast ^{13}O beam and a ^{9}Be target. The resonance was found in the invariant-mass distribution of 3p+^{10}C events and probably corresponds to a 5/2^{+} excited state. The ground state was also expected to be populated, but was not resolved from the background. The observed level decays via initial proton emissions to both the ground and first 2^{+} state of ^{12}O, which subsequently undergo 2p decay. In addition, there may also be a significant proton decay branch to the second 2^{+} level in ^{12}O. The wave function associated with the observed level may be collectivized due to coupling to the continuum as is it located just above the threshold for proton decay to the 2_{2}^{+} state of ^{12}O.

7.
Phys Rev Lett ; 125(20): 202701, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33258618

RESUMEN

Type-I x-ray bursts can reveal the properties of an accreting neutron star system when compared with astrophysics model calculations. However, model results are sensitive to a handful of uncertain nuclear reaction rates, such as ^{22}Mg(α,p). We report the first direct measurement of ^{22}Mg(α,p), performed with the Active Target Time Projection Chamber. The corresponding astrophysical reaction rate is orders of magnitude larger than determined from a previous indirect measurement in a broad temperature range. Our new measurement suggests a less-compact neutron star in the source GS1826-24.

8.
Phys Rev Lett ; 125(1): 012501, 2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-32678621

RESUMEN

Twenty-one two-proton knockout (p,3p) cross sections were measured from neutron-rich nuclei at ∼250 MeV/nucleon in inverse kinematics. The angular distribution of the three emitted protons was determined for the first time, demonstrating that the (p,3p) kinematics are consistent with two sequential proton-proton collisions within the projectile nucleus. Ratios of (p,3p) over (p,2p) inclusive cross sections follow the trend of other many-nucleon removal reactions, further reinforcing the sequential nature of (p,3p) in neutron-rich nuclei.

9.
Phys Rev Lett ; 124(25): 252502, 2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32639781

RESUMEN

In an experiment performed at Lawrence Berkeley National Laboratory's 88-inch cyclotron, the isotope ^{244}Md was produced in the ^{209}Bi(^{40}Ar,5n) reaction. Decay properties of ^{244}Md were measured at the focal plane of the Berkeley Gas-filled Separator, and the mass number assignment of A=244 was confirmed with the apparatus for the identification of nuclide A. The isotope ^{244}Md is reported to have one, possibly two, α-decaying states with α energies of 8.66(2) and 8.31(2) MeV and half-lives of 0.4_{-0.1}^{+0.4} and ∼6 s, respectively. Additionally, first evidence of the α decay of ^{236}Bk was observed and is reported.

11.
Phys Rev Lett ; 123(8): 082501, 2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-31491233

RESUMEN

The elusive ß^{-}p^{+} decay was observed in ^{11}Be by directly measuring the emitted protons and their energy distribution for the first time with the prototype Active Target Time Projection Chamber in an experiment performed at ISAC-TRIUMF. The measured ß^{-}p^{+} branching ratio is orders of magnitude larger than any previous theoretical model predicted. This can be explained by the presence of a narrow resonance in ^{11}B above the proton separation energy.

13.
Nature ; 569(7754): 53-58, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31043730

RESUMEN

Nuclear magic numbers correspond to fully occupied energy shells of protons or neutrons inside atomic nuclei. Doubly magic nuclei, with magic numbers for both protons and neutrons, are spherical and extremely rare across the nuclear landscape. Although the sequence of magic numbers is well established for stable nuclei, experimental evidence has revealed modifications for nuclei with a large asymmetry between proton and neutron numbers. Here we provide a spectroscopic study of the doubly magic nucleus 78Ni, which contains fourteen neutrons more than the heaviest stable nickel isotope. We provide direct evidence of its doubly magic nature, which is also predicted by ab initio calculations based on chiral effective-field theory interactions and the quasi-particle random-phase approximation. Our results also indicate the breakdown of the neutron magic number 50 and proton magic number 28 beyond this stronghold, caused by a competing deformed structure. State-of-the-art phenomenological shell-model calculations reproduce this shape coexistence, predicting a rapid transition from spherical to deformed ground states, with 78Ni as the turning point.

14.
Phys Rev Lett ; 122(16): 162503, 2019 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-31075035

RESUMEN

Fifty-five inclusive single nucleon-removal cross sections from medium mass neutron-rich nuclei impinging on a hydrogen target at ∼250 MeV/nucleon are measured at the RIKEN Radioactive Isotope Beam Factory. Systematically higher cross sections are found for proton removal from nuclei with an even number of protons as compared to odd-proton number projectiles for a given neutron separation energy. Neutron removal cross sections display no even-odd splitting, contrary to nuclear cascade model predictions. Both effects are understood through simple considerations of neutron separation energies and bound state level densities originating in pairing correlations in the daughter nuclei. These conclusions are supported by comparison with semimicroscopic model predictions, highlighting the enhanced role of low-lying level densities in nucleon-removal cross sections from loosely bound nuclei.

15.
Phys Rev Lett ; 122(12): 122501, 2019 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-30978039

RESUMEN

The structure of the extremely proton-rich nucleus _{8}^{11}O_{3}, the mirror of the two-neutron halo nucleus _{3}^{11}Li_{8}, has been studied experimentally for the first time. Following two-neutron knockout reactions with a ^{13}O beam, the ^{11}O decay products were detected after two-proton emission and used to construct an invariant-mass spectrum. A broad peak of width ∼3.4 MeV was observed. Within the Gamow coupled-channel approach, it was concluded that this peak is a multiplet with contributions from the four lowest ^{11}O resonant states: J^{π}=3/2_{1}^{-}, 3/2_{2}^{-}, 5/2_{1}^{+}, and 5/2_{2}^{+}. The widths and configurations of these states show strong, nonmonotonic dependencies on the depth of the p-^{9}C potential. This unusual behavior is due to the presence of a broad threshold resonant state in ^{10}N, which is an analog of the virtual state in ^{10}Li in the presence of the Coulomb potential. After optimizing the model to the data, only a moderate isospin asymmetry between ground states of ^{11}O and ^{11}Li was found.

16.
Anal Biochem ; 570: 56-61, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30768924

RESUMEN

One of the most used formats in inmuno-polymerase chain reaction (IPCR) is known as "Universal" IPCR (signal-generating complexes is based on conjugates of biotinylated DNA, biotinylated IgG and avidin). In the present study, we evaluated the utility of using mono- and bi-biotinylated DNA probes, pre-self-assembled DNA-neutravidin complex, blocking step and glutaraldehyde pretreatment of standard PCR tubes to improve the analytical performance of the hTSH-IPCR assay. The use of pre-self-assembled mono-biotinylated DNA-neutravidin complex enhances both the sensitivity and the reproducibility of the hTSH-IPCR assay, even without blocking step: hTSH-IPCR assay showed an improved limit of detection (LOD: 0.01 µIU/ml), calibration sensitivity (SEN: 2.4) and analytic sensitivity (γ: 9 µIU/ml-1) in comparison with both a self-made ELISA and a commercial one.


Asunto(s)
Reacción en Cadena de la Polimerasa/métodos , Tirotropina/análisis , Biotinilación , Sondas de ADN/química , Sondas de ADN/metabolismo , Humanos , Inmunoensayo , Límite de Detección , Reacción en Cadena de la Polimerasa/instrumentación , Reproducibilidad de los Resultados , Tirotropina/genética
18.
Toxicol Lett ; 303: 48-54, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30599193

RESUMEN

Our goal was to study the effect of BP3 (benzophenone 3) in the follicular assembly and the potential involvement of Foxl2 pathway using whole ovary cultures. Ovaries were collected from Wistar rats at birth, treated in vitro with vehicle (0.01% DMSO), BP3 (5.8 nM, 276 nM, 576 nM and 876 nM) or ESR2 inhibitor (0.1 nM), and cultured for 7 days. Nest breakdown, follicular assembly and the expression of several regulators of these processes (p27, Foxl2, Sox9, Bmp2, Cyp19 and Fst) were evaluated. In vitro exposure to BP3 (5.8 nM) decreased the population of total oocytes, the number of nests per ovary and early primary follicles population. In addition, BP3 (5.8 nM) induced overexpression of Foxl2 mRNA levels through ESR2 but increased Fst mRNA levels independently from ESR2 or Foxl2. We also observed that the number of p27-positive oocytes was decreased after BP3 (5.8 nM). On the other hand, exposure to BP3-276 increased total oocytes, the number of nests per ovary and decreased primary follicles. In addition, BP3-276 induced no changes of Foxl2 mRNA levels through ESR2 but increased Fst mRNA levels independently from ESR2 or Foxl2. In conclusion, our study clearly shows that exposure to BP3 is to perturb the early events of germ cell development as showed here in whole ovary cultures.


Asunto(s)
Benzofenonas/toxicidad , Folículo Ovárico/efectos de los fármacos , Animales , Proteína Morfogenética Ósea 2/genética , Proteína Morfogenética Ósea 2/metabolismo , Diferenciación Celular/efectos de los fármacos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Familia 19 del Citocromo P450/genética , Familia 19 del Citocromo P450/metabolismo , Femenino , Proteína Forkhead Box L2/genética , Proteína Forkhead Box L2/metabolismo , Regulación de la Expresión Génica , Células Germinativas/efectos de los fármacos , Células Germinativas/crecimiento & desarrollo , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Folículo Ovárico/citología , Folículo Ovárico/metabolismo , Ratas , Ratas Wistar , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Técnicas de Cultivo de Tejidos
20.
Rev. otorrinolaringol. cir. cabeza cuello ; 78(3): 235-244, set. 2018. tab, ilus
Artículo en Español | LILACS | ID: biblio-978807

RESUMEN

RESUMEN Introducción: Entre las alteraciones del dorso nasal puede encontrarse desde un rádix bajo hasta un aplastamiento severo del dorso nasal, siendo fundamental el uso de injertos y material de relleno. Objetivo: Proponer una nueva alternativa de relleno y camuflaje en rinoplastía mediante un injerto mixto de L-PRF más cartílago picado en una matriz de fibrina autóloga. Material y método: Evaluación de los pacientes operados de rinoseptoplastía en quienes se utilizó el injerto mixto entre febrero y septiembre del año 2016 en el Servicio de Otorrinolaringología del Hospital Regional de Concepción. Evaluación de resultados respecto a reabsorción e irregularidades del injerto y autoevaluación del grado de satisfacción. Resultados: Fueron operados 7 pacientes. Cuatro de ellos presentaban aplastamiento severo de dorso nasal y tres un rádix profundo. Se logró el relleno y camuflaje del área deseada en todos los casos. No se presentó desplazamiento ni reabsorción del injerto en ninguno de los casos. El uso de este injerto no significó mayor costo económico, y el grado de satisfacción fue alto en todos los casos. Conclusión: Primer estudio en utilizar un injerto mixto de cartílago más L-PRF en una matriz de fibrina autóloga en rinoplastía, demostrando ser una alternativa asequible, efectiva, reproducible y segura, particularmente útil en casos de revisión.


ABSTRACT Introduction: Among the alterations of the nasal dorsum there can be found from a low radix to a severe crushing of the nasal dorsum, being fundamental the use of grafts and filling materials. Aim: To propose a new filling and camouflage alternative in rhinoplasty by means of a mixed graft of L-PRF and chopped cartilage in an autologous fibrin matrix. Material and method: Evaluation of the operated patients of rhinoseptoplasty in whom the mixed graft was used between February and September 2016 in the Otorhinolaryngology unit of the Hospital Regional de Concepción. Evaluation of results regarding resorption and graft irregularities and self-assessment of degree of satisfaction. Results: Seven patients were operated. Four of them presented severe crushing of the nasal dorsum and three of them a deep radix. The filling and camouflage of desired area was achieved in all cases. There were no displacement or resorption of the graft in any case. The use of this graft did not mean greater economic cost, and the degree of satisfaction was high in all cases. Conclusions: First study to use a mixed graft of cartilage and L-PRF in an autologous fibrin matrix in rhinoplasty, proving to be an affordable, effective, reproducible and safe alternative, particularly useful in revision surgeries.


Asunto(s)
Rinoplastia/métodos , Cartílago/trasplante , Chile , Nariz/cirugía , Fibrina Rica en Plaquetas
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