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1.
Phys Rev Lett ; 133(5): 052702, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39159101

ABSTRACT

Asymptotic giant branch stars are responsible for the production of most of the heavy isotopes beyond Sr observed in the solar system. Among them, isotopes shielded from the r-process contribution by their stable isobars are defined as s-only nuclei. For a long time the abundance of ^{204}Pb, the heaviest s-only isotope, has been a topic of debate because state-of-the-art stellar models appeared to systematically underestimate its solar abundance. Besides the impact of uncertainties from stellar models and galactic chemical evolution simulations, this discrepancy was further obscured by rather divergent theoretical estimates for the neutron capture cross section of its radioactive precursor in the neutron-capture flow, ^{204}Tl (t_{1/2}=3.78 yr), and by the lack of experimental data on this reaction. We present the first ever neutron capture measurement on ^{204}Tl, conducted at the CERN neutron time-of-flight facility n_TOF, employing a sample of only 9 mg of ^{204}Tl produced at the Institute Laue Langevin high flux reactor. By complementing our new results with semiempirical calculations we obtained, at the s-process temperatures of kT≈8 keV and kT≈30 keV, Maxwellian-averaged cross sections (MACS) of 580(168) mb and 260(90) mb, respectively. These figures are about 3% lower and 20% higher than the corresponding values widely used in astrophysical calculations, which were based only on theoretical calculations. By using the new ^{204}Tl MACS, the uncertainty arising from the ^{204}Tl(n,γ) cross section on the s-process abundance of ^{204}Pb has been reduced from ∼30% down to +8%/-6%, and the s-process calculations are in agreement with the latest solar system abundance of ^{204}Pb reported by K. Lodders in 2021.

2.
Phys Rev Lett ; 132(12): 122701, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38579210

ABSTRACT

^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.

3.
Neurología (Barc., Ed. impr.) ; 38(9): 653-662, Nov-Dic. 2023. tab, ilus, graf
Article in Spanish | IBECS | ID: ibc-227349

ABSTRACT

Introducción: El Fototest y el Mini-Cog incluyen todos los dominios que debieran formar parte de una evaluación cognitiva. Nuestro objetivo es evaluar la utilidad diagnóstica del uso conjunto de ambos instrumentos para el diagnóstico de deterioro cognitivo (DC). Métodos: Estudio fase iii de evaluación de pruebas diagnósticas con 2 muestras independientes, estudio (448 sujetos), dividida aleatoriamente en 2 dataset (Base 80%, Test 20%), y Externa (61 sujetos). Prueba index: Fototest y Mini-Cog aplicados consecutivamente; prueba de referencia: evaluación cognitiva formal. Se evalúa la UD del uso combinado y escalonado de los modelos simple (Comb-Simple), regresión logística (Comb-RL) y árbol aleatorio (Comb-AA) para identificar DC (GDS ≥ 3). Se realiza un análisis exploratorio en Base seleccionando los criterios que maximizan la exactitud; la evaluación se realiza en las muestras Test y externa mediante un análisis preespecificado con los criterios seleccionados. Resultados: La UD de los modelos combinados en Base (Comb-Simple 88,3 [(88,5-91,4] [exactitud, LI95%-LS95%], Comb-RL 91.6 [88,2-94,3] y Comb-AA 95,2 [92,5-97,2])) es significativamente superior a la de Mini-Cog y Fototest (81,6 [77,1-85,4] y 84,9 [80,8-88,5], respectivamente); estos resultados son replicados en Test (Comb-Simple 88,9 [exactitud], Comb-RL 95,6 y Comb-AA 92,2) y externa (Comb-Simple 91,8, Comb-RL 90,2 y Comb-AA 88,5). La aplicación escalonada mantiene la misma UD pero requiere menos tiempo (197,3 ± 56,7 vs. 233,9 ± 45,2, p < 0,0001). Conclusiones: El uso conjunto del Fototest y el Mini-Cog requiere menos de 4 min y mejora la UD de ambos instrumentos. El uso escalonado es más eficiente porque manteniendo la misma UD requiere menos tiempo de aplicación.(AU)


Introduction: The Fototest and Mini-Cog include all the domains that are necessary in a cognitive assessment. This study aims to evaluate the diagnostic accuracy of the combined use of both instruments for detecting cognitive impairment. Methods: We performed a phase iii diagnostic accuracy study with 2 independent samples: STUDY, which included 448 participants randomly allocated to 2 datasets (BASE [80%] and TEST [20%]); and EXTERNAL, which included 61 participants. The index test was consecutive administration of the Fototest and Mini-Cog, and the reference test was formal cognitive assessment. We evaluated the diagnostic accuracy of two-step vs. consecutive application of the tests and simple (Comb-Simple), logistic regression (Comb-LR), and random decision tree (Comb-RDT) models of their combined use for detecting cognitive impairment (Global Deterioration Scale score ≥ 3). We performed an exploratory analysis of the BASE dataset, selecting criteria that maximise accuracy; a pre-specified analysis was used to evaluate the selected criteria in the TEST and EXTERNAL datasets. Results: The diagnostic accuracy (95% confidence interval) of the combined models in the BASE dataset (Comb-Simple: 88.3 [88.5-91.4]; Comb-LR: 91.6 [88.2-94.3]; Comb-RDT 95.2 [92.5-97.2]) was significantly higher than the individual values observed for the Mini-Cog and Fototest (81.6 [77.1-85.4] and 84.9 [80.8-88.5], respectively). These results were replicated in the TEST (Comb-Simple: 88.9; Comb-LR: 95.6; Comb-RDT: 92.2) and EXTERNAL datasets (Comb-Simple: 91.8; Comb-LR: 90.2; Comb-RDT: 88.5). Two-step application had the same diagnostic accuracy than consecutive application but required less time (mean [SD] of 197.3 s [56.7] vs. 233.9 s [45.2]; P<.0001). Conclusions: Combined application of the Fototest and Mini-Cog takes less than 4 minutes and improves the diagnostic accuracy of both instruments. Two-step application is more efficient as it requires less...(AU)


Subject(s)
Humans , Male , Female , Cognitive Dysfunction , Predictive Value of Tests , Mental Status and Dementia Tests , Neuropsychological Tests , Diagnostic Techniques and Procedures , Neurology , Nervous System Diseases , Mass Screening
4.
Neurologia (Engl Ed) ; 38(9): 653-662, 2023.
Article in English | MEDLINE | ID: mdl-37858894

ABSTRACT

INTRODUCTION: The Fototest and Mini-Cog include all the domains that are necessary in a cognitive assessment. This study aims to evaluate the diagnostic accuracy of the combined use of both instruments for detecting cognitive impairment. METHODS: We performed a phase III diagnostic accuracy study with 2 independent samples: STUDY, which included 448 participants randomly allocated to 2 datasets (BASE [80%] and TEST [20%]); and EXTERNAL, which included 61 participants. The index test was consecutive administration of the Fototest and Mini-Cog, and the reference test was formal cognitive assessment. We evaluated the diagnostic accuracy of two-step vs consecutive application of the tests and simple (Comb-Simple), logistic regression (Comb-LR), and random decision tree (Comb-RDT) models of their combined use for detecting cognitive impairment (Global Deterioration Scale score ≥ 3). We performed an exploratory analysis of the BASE dataset, selecting criteria that maximise accuracy; a pre-specified analysis was used to evaluate the selected criteria in the TEST and EXTERNAL datasets. RESULTS: The diagnostic accuracy (95% confidence interval) of the combined models in the BASE dataset (Comb-Simple: 88.3 [88.5-91.4]; Comb-LR: 91.6 [88.2-94.3]; Comb-RDT 95.2 [92.5-97.2]) was significantly higher than the individual values observed for the Mini-Cog and Fototest (81.6 [77.1-85.4] and 84.9 [80.8-88.5], respectively). These results were replicated in the TEST (Comb-Simple: 88.9; Comb-LR: 95.6; Comb-RDT: 92.2) and EXTERNAL datasets (Comb-Simple: 91.8; Comb-LR: 90.2; Comb-RDT: 88.5). Two-step application had the same diagnostic accuracy than consecutive application but required less time (mean [SD] of 197.3 s [56.7] vs 233.9 s [45.2]; P < .0001). CONCLUSIONS: Combined application of the Fototest and Mini-Cog takes less than 4 minutes and improves the diagnostic accuracy of both instruments. Two-step application is more efficient as it requires less time while maintaining the same diagnostic accuracy.


Subject(s)
Cognitive Dysfunction , Dementia , Humans , Cognitive Dysfunction/diagnosis , Dementia/diagnosis , Mental Status and Dementia Tests
5.
O.F.I.L ; 33(1)2023. tab
Article in Spanish | IBECS | ID: ibc-220696

ABSTRACT

Objetivo: Evaluar las preferencias y satisfacción de los pacientes con asma grave, relacionadas con el lugar de administración de fármacos biológicos subcutáneos: hospital, centro de salud y domicilio, durante la pandemia COVID-19. Métodos: Estudio observacional, descriptivo y transversal que analizó, mediante una encuesta telefónica realizada del 23 al 27 de noviembre de 2020, las preferencias y el grado de satisfacción con la administración de fármacos biológicos subcutáneos en pacientes asmáticos atendidos en la consulta de Alergología de un Hospital General. Resultados: Respondieron la encuesta 33 pacientes, edad media 51,5 años, 57,6% mujeres. Un 57,6% de los pacientes se administraron los fármacos (omalizumab, mepolizumab y benralizumab) en su domicilio, 21,2% en el Hospital de Día y en el Centro de Salud, respectivamente. Los motivos para la administración fuera del hospital fueron la comodidad y evitar el contagio por virus SARS-CoV-2 (30,7%).Tras la pandemia, los pacientes preferían continuar con la dispensación y autoadministración domiciliaria del biológico y tener consultas médicas presenciales. El grado de satisfacción fue 9,7 (escala 0 a 10). Conclusiones: Los pacientes prefieren autoadministrarse en su domicilio los fármacos biológicos para el AG con el apoyo de la dispensación domiciliaria de éstos, mostrando un alto grado de satisfacción por la comodidad que les aporta. Finalizada la pandemia, demandan que las visitas médicas sean presenciales pero desean continuar autoadministrándose el fármaco tras su dispensación domiciliaria por el Servicio de Farmacia. (AU)


Objective: To assess preferences and satisfaction of patients with severe asthma about the place of administration of subcutaneous biological drugs: hospital, health center and home, during the COVID-19 pandemic. Methods: Observational, descriptive and cross-sectional study that analyzed, from November 23 to 27, 2020, through a telephone survey, the preferences and degree of satisfaction with the administration of subcutaneous biological drugs in asthmatic patients treated in the Allergology consultation of a General Hospital. Results: A total of 33 patients responded to the survey, the mean age was 51.5 years, 57.6% were women. The patients that received subcutaneous biological drugs (omalizumab, mepolizumab and benralizumab) at home were 57,6%, at the Day Hospital and at the Health Center 21,2 %, in both cases. The reasons for the administration outside the hospital were comfort and to avoid the spread of the SAR-CoV-2 virus (30.7%). After the pandemic, patients prefer home deliveries, self-administration and face-to-face medical consultations. The degree of satisfaction with the treatment was very high. Conclusions: Patients prefer to self-administer biological drugs for GA at home with the support of their home dispensing, showing a high degree of satisfaction with the comfort it provides. Once the pandemic is over, they demand that medical visits be face-to-face but they want to continue self-administering the drug after it is dispensed at home by the Pharmacy Service. (AU)


Subject(s)
Humans , Male , Female , Adult , Patient Satisfaction/statistics & numerical data , Asthma/therapy , Biological Products/administration & dosage , Biological Products/therapeutic use , Residential Treatment , Pandemics , Coronavirus Infections/epidemiology , Surveys and Questionnaires
6.
Eur Phys J A Hadron Nucl ; 58(12): 239, 2022.
Article in English | MEDLINE | ID: mdl-36514540

ABSTRACT

Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.

7.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Article in English | MEDLINE | ID: mdl-36332266

ABSTRACT

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

8.
Sci Rep ; 12(1): 18238, 2022 10 29.
Article in English | MEDLINE | ID: mdl-36309532

ABSTRACT

The information provided by a person with multiple sclerosis (MS) may anticipate changes in the course of the disease. To explore the role of a set of standardized patient-reported outcomes (PRO) in predicting disability progression in MS an observational study was conducted in two cohorts of 30 and 86 persons with progressive MS (pwPMS) and relapsing MS (pwRMS), respectively. The associations between baseline clinical, biochemical variables and results on MS quality of life scale (MusiQol), Modified Fatigue Impact Scale (MFIS) and Beck Depression Inventory II (BDI-II) were analyzed. The progression of disability after 2 years of follow-up in pwRMS was investigated. We show that PRO differentiated pwRMS and pwPMS cohorts with lower MusiQoL and higher MFIS and BDI-II scores in the latter. Only MFIS was correlated with disability in pwRMS and high scores in the physical MFIS domain associated with worse performance in 9HPT, and a trend in T25FW and SDMT. Instead, the cognitive MFIS domain was correlated with CHI3L1 in cerebrospinal fluid, a biomarker of progression. At the end of the study, global MFIS and BDI-II were found to be independent risk factors for disability independent of relapse. Although all PRO measures explored were altered in pwPMS, baseline MFIS discriminated current and prospective disability in pwRMS, identifying patients at risk of progression.


Subject(s)
Multiple Sclerosis , Humans , Multiple Sclerosis/complications , Fatigue/etiology , Disability Evaluation , Quality of Life , Prospective Studies
9.
Science ; 378(6618): 412-417, 2022 10 28.
Article in English | MEDLINE | ID: mdl-36302013

ABSTRACT

Two >130-meter-diameter impact craters formed on Mars during the later half of 2021. These are the two largest fresh impact craters discovered by the Mars Reconnaissance Orbiter since operations started 16 years ago. The impacts created two of the largest seismic events (magnitudes greater than 4) recorded by InSight during its 3-year mission. The combination of orbital imagery and seismic ground motion enables the investigation of subsurface and atmospheric energy partitioning of the impact process on a planet with a thin atmosphere and the first direct test of martian deep-interior seismic models with known event distances. The impact at 35°N excavated blocks of water ice, which is the lowest latitude at which ice has been directly observed on Mars.

10.
Phys Rev Lett ; 129(11): 112501, 2022 Sep 09.
Article in English | MEDLINE | ID: mdl-36154392

ABSTRACT

The reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood. The conclusion is that seniority is largely conserved in the first πg_{9/2} orbital.

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