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1.
Nature ; 623(7989): 932-937, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38030780

RESUMEN

Planets with radii between that of the Earth and Neptune (hereafter referred to as 'sub-Neptunes') are found in close-in orbits around more than half of all Sun-like stars1,2. However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the planets follow a chain of resonant orbits. A dynamical study of the innermost planet triplet allowed the prediction and later confirmation of the orbits of the rest of the planets in the system. The six planets are found to be sub-Neptunes with radii ranging from 1.94R⊕ to 2.85R⊕. Three of the planets have measured masses, yielding low bulk densities that suggest the presence of large hydrogen-dominated atmospheres.

2.
Phys Rev Lett ; 133(5): 052702, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39159101

RESUMEN

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.

3.
Eur Phys J A Hadron Nucl ; 58(12): 239, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36514540

RESUMEN

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.

4.
Eur Cell Mater ; 41: 558-575, 2021 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-34021906

RESUMEN

Embryonic muscle forces are necessary for normal vertebral development and spinal curvature, but their involvement in intervertebral disc (IVD) development remains unclear. The aim of the current study was to determine how muscle contractions affect (1) notochord involution and vertebral segmentation, and (2) IVD development including the mechanical properties and morphology, as well as collagen fibre alignment in the annulus fibrosus. Muscular dysgenesis (mdg) mice were harvested at three prenatal stages: at Theiler Stage (TS)22 when notochord involution starts, at TS24 when involution is complete, and at TS27 when the IVD is formed. Vertebral and IVD development were characterised using histology, immunofluorescence, and indentation testing. The results revealed that notochord involution and vertebral segmentation occurred independently of muscle contractions between TS22 and TS24. However, in the absence of muscle contractions, we found vertebral fusion in the cervical region at TS27, along with (i) a displacement of the nucleus pulposus towards the dorsal side, (ii) a disruption of the structural arrangement of collagen in the annulus fibrosus, and (iii) an increase in viscous behaviour of the annulus fibrosus. These findings emphasise the important role of mechanical forces during IVD development, and demonstrate a critical role of muscle loading during development to enable proper annulus fibrosus formation. They further suggest a need for mechanical loading in the creation of fibre-reinforced tissue engineering replacement IVDs as a therapy for IVD degeneration.


Asunto(s)
Disco Intervertebral/fisiología , Músculos/fisiología , Notocorda/fisiología , Animales , Anillo Fibroso/metabolismo , Anillo Fibroso/fisiología , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiología , Femenino , Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Músculos/metabolismo , Notocorda/metabolismo , Núcleo Pulposo/metabolismo , Núcleo Pulposo/fisiología
5.
Phys Rev Lett ; 125(14): 142701, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33064503

RESUMEN

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.

6.
J Radiol Prot ; 40(2): 583-595, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32143202

RESUMEN

The newly developed mesh-type reference computational phantoms (MRCPs) represent the evolution of the previous reference phantoms and a more detailed description of the human body, addressing the voxel reference phantom limitations. These allow for a more accurate dose calculation in the human body, which in some cases results in a significant difference of the calculated quantities. In this work, the absorbed dose calculation due to neutrons and gammas was calculated using a voxel and a mesh-type computational phantom. The goal was to understand how a more accurate description of the human body affects the estimated neutron dose. The phantoms were tested in a real-case scenario: they were placed in front of a neutron Howitzer container model using PHITS. This model corresponds to the neutron Howitzer container at the Neutron Measurements Laboratory of the Energy Engineering Department of the Polytechnic University of Madrid (UPM), and at the time of measurement it was equipped with a 241Am-Be neutron source of 74 GBq in its center. The container allows the source to be in either the irradiation or the storage position. Results show that when dealing with neutrons, the dose deviation when using GOLEM or the MRCP leads to a general 20%-30% deviation that goes up to above 400% in small thin structures such as the eye.


Asunto(s)
Modelos Anatómicos , Dosis de Radiación , Radiometría/instrumentación , Diseño de Equipo , Rayos gamma , Humanos , Método de Montecarlo , Neutrones
7.
Rheumatol Int ; 38(3): 343-351, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29185087

RESUMEN

This study aims to evaluate the use of assistive devices as a strategy in non-pharmacological treatment for hand osteoarthritis (HOA). This is a randomized, prospective, parallel, assessor-blinded clinical trial, in which patients with a diagnosis of HOA were randomly allocated to an intervention group (IG), where they received assistive devices for daily life activities, or to a control group (CG), where they received a guideline leaflet with information on joint protection and disease features. The primary outcomes considered were occupational performance, measured by the Canadian Occupational Performance Measure (COPM), and hand function was evaluated through the Score for the Assessment and Quantification of Chronic Rheumatoid Affections of the Hands (SACRAH). The secondary outcomes were pain, measured by the visual analog scale (VAS), and quality of life, measured by the World Health Organization Quality of Life Instrument, Short Form (WHOQOL-BREF). We compared both outcomes before and after interventions and outcomes between groups. Participants from the two groups were assessed at the time of inclusion in the study, 30, and 90 days after initial evaluation. Out of the 39 patients included, 19 were allocated to the IG and 20 to the CG. Only two patients from the CG did not complete the follow-up period. The patients' hand function and occupational performance improved after intervention (30 days-SACRAH-p < 0.05; COPM-p < 0.05; VAS-p < 0.05). When comparing results between the groups, there was a statistical difference in COPM (performance-p < 0.001; and satisfaction-p < 0.001), in the first reevaluation carried out. The use of assistive devices has proved to be an effective alternative in non-pharmacological treatment for HOA. CLINICAL TRIAL REGISTRATION: NCT02667145.


Asunto(s)
Actividades Cotidianas , Ergonomía , Articulaciones de la Mano/fisiopatología , Artículos Domésticos , Osteoartritis/terapia , Dispositivos de Autoayuda , Anciano , Fenómenos Biomecánicos , Brasil , Evaluación de la Discapacidad , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/diagnóstico , Osteoartritis/fisiopatología , Dimensión del Dolor , Estudios Prospectivos , Calidad de Vida , Recuperación de la Función , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
8.
Dis Esophagus ; 11(1): 48-50, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29040491

RESUMEN

Although the use of the posterior mediastinum and the stomach as a reconstruction option after esophagectomy has large acceptance all over the world, there are concerns about the potential respiratory impairment it could cause. We prospectively studied 35 patients regarding the forced expiratory volume and vital capacity. The patients were studied preoperatively and between the 45th and 60th postoperative days. The value of both parameters decreased, although they were still within normal clinical ranges. We concluded that this type of reconstruction does not harm the patients regarding the respiratory flow rates.


Asunto(s)
Neoplasias Esofágicas/cirugía , Esofagoplastia/efectos adversos , Esófago/cirugía , Sistema Respiratorio/fisiopatología , Estómago/cirugía , Anciano , Anastomosis Quirúrgica , Esofagectomía , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Mediastino , Persona de Mediana Edad , Periodo Posoperatorio , Periodo Preoperatorio , Estudios Prospectivos , Capacidad Vital
9.
Phys Rev Lett ; 117(15): 152701, 2016 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-27768364

RESUMEN

The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.

10.
Scand J Med Sci Sports ; 25(1): 53-60, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24256097

RESUMEN

This study investigated the effect of the dihydropyridine calcium channel antagonist, amlodipine, on blood pressure (BP) during resistance exercise performed at different intensities in hypertensives. Eleven hypertensives underwent 4 weeks of placebo and amlodipine (random double-blinded crossover design). In each phase, they performed knee extension exercise until exhaustion following three protocols: one set at 100% of 1 RM (repetition maximum), three sets at 80% of 1 RM, and three sets at 40% of 1 RM. Intraarterial BP was measured before and during exercise. Amlodipine reduced maximal systolic/diastolic BP values achieved at all intensities (100% = 225 ± 6/141 ± 3 vs. 207 ± 6/130 ± 6 mmHg; 80% = 289 ± 8/178 ± 5 vs. 273 ± 10/169 ± 6 mmHg; 40% = 289 ± 10/176 ± 8 vs. 271 ± 11/154 ± 6 mmHg). Amlodipine blunted the increase in diastolic BP that occurred during the second and third sets of exercise at 40% of 1RM (+75 ± 6 vs. +61 ± 5 mmHg and +78 ± 7 vs. +64 ± 5 mmHg, respectively). Amlodipine was effective in reducing the absolute values of systolic and diastolic BP during resistance exercise and in preventing the progressive increase in diastolic BP that occurs over sets of low-intensity exercise. These results suggest that systemic vascular resistance is involved in BP increase during resistance exercise, and imply that hypertensives receiving amlodipine are at lower risk of increased BP during resistance exercise than non-medicated patients.


Asunto(s)
Amlodipino/uso terapéutico , Presión Arterial/fisiología , Bloqueadores de los Canales de Calcio/uso terapéutico , Hipertensión/tratamiento farmacológico , Entrenamiento de Fuerza , Adulto , Estudios Cruzados , Método Doble Ciego , Ejercicio Físico/fisiología , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad
11.
Exp Cell Res ; 317(6): 770-80, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21255567

RESUMEN

With the goal of obtaining clinically safe human adipose-derived stroma/stem cells (ASC) and eliminating the use of serum, we have developed a new culture system that allows the expansion of ASC as spheres in a defined medium. These spheres can be passaged several times. They are not only aggregated cells but rather originate from single cells as clonal spheres can be obtained after seeding at very low density and reform clonal spheres after dissociation. These spheres can also revert to monolayer growth when plated in medium containing human plasma and even generate fibroblast-like colonies (CFU-f). Under several differentiation-specific media, spheres-derived ASC maintain their capacity to differentiate into osteoblasts, endothelial cells and adipocytes. These results indicate that human ASC can be maintained in a serum-free 3D culture system, which is of great interest for the expansion in bioreactors of autologous ASC and their use in clinical trials.


Asunto(s)
Adipocitos/citología , Tejido Adiposo/citología , Técnicas de Cultivo de Célula/métodos , Células Madre Mesenquimatosas/citología , Diferenciación Celular , Linaje de la Célula , Medio de Cultivo Libre de Suero , Citometría de Flujo , Humanos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Gen Dent ; 60(6): 494-500; quiz p. 501-2, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23220304

RESUMEN

Periodontitis is a primarily bacterial infection that is common in dentate individuals, while denture stomatitis is a predominantly fungal infection that is common among denture wearers. Both infections may increase a patient's risk for chronic systemic infection dissemination, and may in turn increase the risk of chronic, inflammatory-based systemic diseases. Systemic diseases for which chronic oral infections are believed to confer attributable risk include atherosclerotic and coronary disease, stroke, chronic obstructive pulmonary disease, diabetes, and hypertension. It appears that invasive oral pathogens trigger a systemic inflammatory response via mediators released by the cardiovascular system and liver, putting the patient at increased risk for these diseases. Data comparing gene expression between denture wearers with and without denture stomatitis (and associated Candida albicans infections) has demonstrated unique up- and down-regulation patterns for a number of genes. It appears that down-regulated genes (whose functions are thereby diminished) are associated with reduced epithelial barrier integrity. By contrast, there appears to be an association between up-regulated genes (which have enhanced function) and inflammatory responses that facilitate the ability of C. albicans to bind with and penetrate the oral mucosa. Molecular biological approaches suggest that future therapeutic development could target reducing either the local inflammatory processor, the binding and attachment of C. albicans to the oral mucosa, or both. Ongoing investigations are attempting to incorporate interventions into matrices, to provide a local and sustained presence to therapeutic interventions.


Asunto(s)
Estado de Salud , Boca Edéntula/microbiología , Salud Bucal , Candidiasis Bucal/inmunología , Enfermedad Crónica , Infección Focal Dental/inmunología , Regulación de la Expresión Génica/genética , Humanos , Boca Edéntula/inmunología , Periodontitis/inmunología , Periodontitis/microbiología , Factores de Riesgo , Estomatitis Subprotética/inmunología , Estomatitis Subprotética/microbiología
13.
Aquat Toxicol ; 244: 106095, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35121565

RESUMEN

The primary focus of environmental toxicological studies is to address the direct effects of chemicals on exposed organisms (parental generation - F0), mostly overlooking effects on subsequent non-exposed generations (F1 and F2 - intergenerational and F3 transgenerational, respectively). Here, we addressed the effects of simvastatin (SIM), one of the most widely prescribed human pharmaceuticals for the primary treatment of hypercholesterolemia, using the keystone crustacean Gammarus locusta. We demonstrate that SIM, at environmentally relevant concentrations, has significant inter and transgenerational (F1 and F3) effects in key signaling pathways involved in crustaceans' neuroendocrine regulation (Ecdysteroids, Catecholamines, NO/cGMP/PKG, GABAergic and Cholinergic signaling pathways), concomitantly with changes in apical endpoints, such as depressed reproduction and growth. These findings are an essential step to improve hazard and risk assessment of biological active compounds, such as SIM, and highlight the importance of studying the transgenerational effects of environmental chemicals in animals' neuroendocrine regulation.


Asunto(s)
Anfípodos , Contaminantes Químicos del Agua , Animales , Reproducción , Simvastatina/toxicidad , Contaminantes Químicos del Agua/toxicidad
14.
Haemophilia ; 17(2): 228-32, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21070500

RESUMEN

There is a lack of publications concerning the use of primary prophylaxis in developing countries. The aim of this study was to evaluate the effectiveness of primary prophylaxis therapy in preventing the development of arthropathy in children with severe haemophilia A or B. From January 1999 to April 2009, a prospective study was carried out involving 39 patients with severe haemophilia A or B. These haemophilia A and haemophilia B patients received 20-40 UI kg(-1) of factors VIII and IX, three and two times per week, respectively. The patients were followed up by a multidisciplinary team. The analysis was carried out in 23 patients who had been on prophylaxis therapy for at least 12 months. The orthopaedic evaluation was performed according to the recommendations of the Orthopedic Advisory Committee of the World Federation of Hemophilia, by evaluating pain and bleeding, and by conducting physical examination and radiological assessment (Pettersson's Joint Score and magnetic resonance): 82.6% of patients who had used the factor regularly did not present any clinical or radiographic changes in the studied joints; 17.4% used the factor irregularly at the beginning of the treatment and of those, most patients presented mild changes in the joints; and 4.3% presented transient knee and ankle pain in spite of regular factor use. The preliminary results of primary prophylaxis confirm its effectiveness in preventing haemophilic arthropathy. Socioeconomic factors did not play a significant role.


Asunto(s)
Factor IX/uso terapéutico , Factor VIII/uso terapéutico , Hemartrosis/prevención & control , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Hemofilia B/complicaciones , Hemofilia B/tratamiento farmacológico , Artropatías/prevención & control , Preescolar , Factor IX/administración & dosificación , Factor VIII/administración & dosificación , Humanos , Lactante , Artropatías/diagnóstico por imagen , Artropatías/etiología , Masculino , Estudios Prospectivos , Radiografía
15.
J Periodontal Res ; 46(2): 246-51, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21241302

RESUMEN

BACKGROUND AND OBJECTIVE: Chemokines are known to regulate leukocyte trafficking, recruitment and infiltration in periodontal diseases. The study objective was to determine the effect of an experimental oral/topical chemokine (C-C motif) receptor 2 (CCR2)-antagonist treatment on alveolar bone loss in a mouse model of Porphyromonas gingivalis-induced periodontitis. MATERIAL AND METHODS: Balb/C mice (n = 41) were randomly assigned to four groups. Group 1 was infected by P. gingivalis applied orally/topically for 5 wk. Group 2 was also infected and then treated with vehicle (aqueous methylcellulose) for an additional 4 wk. Group 3 was infected and orally/topically treated with CCR2 antagonist (10 mg/kg). Group 4 served as a noninfected, nontreated control group. Mice received intraperitoneal injections of Alizarin (30 mg/kg) and calcein (20 mg/kg) three times from the last day of infection to determine mineral deposition, reflecting bone dynamics. Mandibles were analysed by morphometry and confocal fluorescence microscopy. RESULTS: Alveolar bone loss was compared among groups using Tukey's test, and bone formation was qualitatively observed. Infected mice showed significantly greater alveolar bone loss than noninfected control animals (group 1 vs. 4, p < 0.01). Vehicle-treated mice (group 2) showed the largest area of alveolar bone loss (p < 0.01), while mice treated with the CCR2 antagonist showed the smallest area of alveolar bone loss and were similar to the control group (group 3 vs. 4, p = 0.14). Qualitative analysis of fluorescent dye uptake indicated increased bone formation in CCR2-antagonist-treated mice, suggesting an improved bone repairing process. CONCLUSION: The results suggested that treatment with CCR2 antagonist inhibited alveolar bone loss and improved bone formation in this model. These data support further evaluation of CCR2 antagonist as a therapeutic target for the development of new treatment modalities on bacterially induced alveolar bone resorption.


Asunto(s)
Pérdida de Hueso Alveolar/tratamiento farmacológico , Receptores CCR2/antagonistas & inhibidores , Administración Tópica , Pérdida de Hueso Alveolar/microbiología , Proceso Alveolar/patología , Animales , Antraquinonas , Infecciones por Bacteroidaceae/microbiología , Remodelación Ósea/efectos de los fármacos , Modelos Animales de Enfermedad , Fluoresceínas , Colorantes Fluorescentes , Mandíbula/patología , Enfermedades Mandibulares/tratamiento farmacológico , Enfermedades Mandibulares/microbiología , Ratones , Ratones Endogámicos BALB C , Microscopía Confocal , Osteogénesis/efectos de los fármacos , Periodontitis/microbiología , Porphyromonas gingivalis/fisiología , Distribución Aleatoria , Receptores CCR2/uso terapéutico , Factores de Tiempo , Cuello del Diente/patología
16.
Appl Radiat Isot ; 170: 109597, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33493792

RESUMEN

Rotating Modulation Collimators (RMC) are devices that can be used to determine the location of a radiation source. In this work, a design with extended field-of-view (FOV) is proposed to allow faster measurements by providing a wider scanned area. Monte Carlo simulations were used to calculate the response of the RMC system, system matrix and modulation profiles. The Maximum Likelihood Expectation Maximization algorithm was used for image reconstruction. The proposed design provides a FOV up to 60° with a maximum error of 5° or up to 70° with a maximum error of 15°.

17.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(8): 408-414, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34340778

RESUMEN

PURPOSE: The aim of this study was to compare the results of intrastromal arcuate incisions (AIs) and transepithelial AIs to treat corneal astigmatism during femtosecond laser-assisted cataract surgery (FLACS). METHODS: This retrospective study included 20 patients with corneal astigmatism between 0.70 and 2.00 diopters (D) who underwent FLACS with concurrent intrastromal AIs in one eye and transepithelial AIs in the fellow eye. The main outcomes measures at 2-3 months of follow-up were the difference between pre-operative and postoperative keratometric corneal cylinder (Kcyl), the correction index (CI) and the percentage of overcorrection. RESULTS: The mean difference between preoperative and postoperative Kcyl revealed a mean value of 0.36 ±â€¯0.37 D in the transepithelial group and 0.53 ±â€¯0.42 D in the intrastromal group (p < 0.001). The mean CI was 0.83 ±â€¯0.71 in the transepithelial group and 0.68 ±â€¯0.29 in intrastromal group (p = 0.17). Five eyes (25 %) had an astigmatism overcorrection in the transepithelial group and 1 eye (5%) in the intrastromal group. CONCLUSIONS: Both intrastromal and transepithelial AIs showed potential for mild to moderate astigmatism correction and appeared to be a safe procedure. Despite transepithelial AIs presented a higher CI, the intrastromal AIs results were more predictable.


Asunto(s)
Astigmatismo , Catarata , Astigmatismo/cirugía , Topografía de la Córnea , Humanos , Terapia por Láser , Rayos Láser , Refracción Ocular , Estudios Retrospectivos , Agudeza Visual
18.
Ultrason Sonochem ; 73: 105541, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33839530

RESUMEN

Copper molybdate nanoplates were synthesized by a sonochemical process at room temperature, which we report as a simple and cost-effective route. Structural analysis of the material by the Rietveld method of X-ray diffraction (XRD) data revealed lindgrenite Cu3(MoO4)2(OH)2 in a single-phase structure. All the vibrational modes characteristic of the space group were identified by Raman vibrational and near-infrared (NIR) spectroscopies. The profile obtained for N2 adsorption/desorption was type III hysteresis, characteristic of mesoporous materials, with a surface area of 70.77(1) m2 g-1. The micrographs of the material obtained by scanning electron microscopy showed nanoplates with nanometric sizes and an anisotropic growth aspect. The catalytic activity of lindgrenite was evaluated by esterifying oleic acid with methanol, showing high conversion rate to methyl oleate and good catalyst stability after seven recycling cycles. Above all, the best catalytic performance was reached when we optimized parameters such as oleic acid:methanol molar ratio of 1:5, 5% of catalyst dosage, and reaction time of 5 h, resulting in 98.38% of conversion at 413 K. Therefore, sonochemically synthesized lindgrenite proved to be a high potential material for biofuel production by oleic acid esterification.

19.
Methods ; 49(4): 316-21, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19409999

RESUMEN

Streptococcus pyogenes causes severe invasive infections: the post-streptococcal sequelae of acute rheumatic fever (RF) and rheumatic heart disease (RHD), acute glomerulonephritis, and uncomplicated pharyngitis and pyoderma. Efforts to produce a vaccine against S. pyogenes began several decades ago, and different models have been proposed. Here, we describe the methodology used in the development of a new vaccine model, consisting of both T and B protective epitopes constructed as synthetic peptides and recombinant proteins. Two adjuvants were tested in an experimental inbred mouse model: a classical Freund's adjuvant and a new adjuvant (AFCo1) that induces mucosal immune responses and is obtained by calcium precipitation of a proteoliposome derived from the outer membrane of Neisseria meningitides B. The StreptInCor vaccine epitope co-administrated with AFCo1 adjuvant induced mucosal (IgA) and systemic (IgG) antibodies as preferential Th1-mediated immune responses. No autoimmune reactions were observed, suggesting that the vaccine epitope is safe.


Asunto(s)
Diseño de Fármacos , Vacunas Estreptocócicas/inmunología , Streptococcus pyogenes/inmunología , Secuencia de Aminoácidos , Animales , Femenino , Inmunidad Mucosa/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Vacunas Estreptocócicas/administración & dosificación , Vacunas Estreptocócicas/síntesis química , Streptococcus pyogenes/efectos de los fármacos
20.
Avian Dis ; 54(3): 1066-71, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20945789

RESUMEN

Beak and feather disease virus (BFDV), a member of the genus Circovirus, was detected in six dead African grey parrots (Psittacus erithacus) in Portugal. The complete nucleotide sequences of these six BFDVs (PT05, PT08, PT08-2, PT08-3, PT09, and PT09-2) were determined and analyzed. The seven open reading frames (ORFs) described for other BFDVs were detected in all strains, except for PT05 and PT08, in which ORFs 4 and 7 are absent. Bayesian inference of phylogeny based on complete genomes of BFDVs isolated in Portugal and 32 other BFDVs found in other parts of the world revealed that PT05 is included in lineage IV, whereas the others form a new proposed genotype lineage IX. The nucleotide diversity ranged from 2% to 12% between the BFDV strains isolated in Portugal and other BFDVs found worldwide.


Asunto(s)
Enfermedades de las Aves/virología , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Loros , Animales , Enfermedades de las Aves/epidemiología , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/virología , Circovirus/aislamiento & purificación , ADN Viral/genética , Genoma Viral , Epidemiología Molecular , Portugal/epidemiología
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