Análisis de diferentes técnicas de ensayos para la evaluación de la adherencia de las capas bituminosas ultradelgadas (AUTL)

La creciente utilización de mezclas Ultradelgadas, conocidas generalmente AUTL (Asphalt Ultra-Thin Layer), han llevado a diversas administraciones a preguntarse si los ensayos que actualmente están recogidos dentro de la normativa son igualmente aplicables a mezclas que se extienden en espesores tan pequeños (10 a 20 mm). Entre los ensayos planteados se encuentra el de adherencia entre capas. La norma actual NLT-382, basada en un método de corte, establece dos dispositivos (A y B) que resultan muy útiles cuando estamos estudiando mezclas que presentan espesores convencionales pero que pueden presentar dificultades a la hora de realizar el ensayo con espesores inferiores a 2 cm. Cabe entonces esclarecer si, para estas mezclas, el ensayo sigue siendo válido o, por el contrario, existen métodos de evaluación que puedan aportar una mayor información sobre este parámetro. En este contexto, un grupo de trabajo liderado por el CEDEX, con la colaboración de un conjunto de empresas y universidades, han iniciado un estudio comparando varios tipos de ensayo diferentes: • Ensayo de corte habitual NLT 382 (contemplado en la pre-norma europea prEN12697-48 -apartado 4.2) realizado por el CEDEX. • Ensayo TAT “Tensile Adhesión Test”, también de la prEN12697-48 [1]. (apartado 4.3.), realizado por la empresa PAVASAL. • Dos ensayos propuestos por la Universidad Politécnica de Cataluña a partir una modificación del ensayo Fénix. En esta comunicación se expone una breve descripción de las condiciones y procedimientos de cada uno de los ensayos mencionados anteriormente. Así como, los resultados comparativos obtenidos con cada una de las metodologías después de analizar las probetas extraídas de un tramo de extendido real sobre diferentes dotaciones de riego (300, 600 y 950 g/m2), analizando los beneficios y las dificultades encontradas.Postprint (published version

Transcranial Magnetic Resonance-Guided Focused Ultrasound Thalamotomy in Essential Tremor: A Comprehensive Lesion Characterization

Background: Transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) thalamotomy is a novel and effective treatment for controlling tremor in essential tremor patients. Objective: To provide a comprehensive characterization of the radiological, topographical, and volumetric aspects of the tcMRgFUS thalamic lesion, and to quantify how they relate to the clinical outcomes. Methods: In this study, clinical and radiological data from forty patients with medically-refractory essential tremor treated with unilateral tcMRgFUS thalamotomy were retrospectively analyzed. Treatment efficacy was assessed with Clinical Rating Scale for Tremor (CRST). Lesions were manually segmented on T1, T2, and susceptibility-weighted images, and 3-dimensional topographical analysis was then carried out. Statistical comparisons were performed using nonparametric statistics. Results: The greatest clinical improvement was correlated with a more inferior and posterior lesion, a bigger lesion volume, and percentage of the ventral intermediate nucleus covered by the lesion; whereas, the largest lesions accounted for the occurrence of gait imbalance. Furthermore, the volume of the lesion was significantly predicted by the number of sonications surpassing 52°C. Conclusion: Here we provide a comprehensive characterization of the thalamic tcMRgFUS lesion including radiological and topographical analysis. Our results indicate that the location and volume of the lesion were significantly associated with the clinical outcome and that mid-temperatures may be responsible for the lesion size. This could serve ultimately to improve targeting and judgment and to optimize clinical outcome of tcMRgFUS thalamotomy.Sin financiación4.654 JCR (2020) Q2, 56/208 Clinical Neurology4.654 SJR (2020) Q1, 56/208 Clinical NeurologyNo data IDR 2020UE

Analysis of different testing techniques for evaluating the adhesion of asphalt ultra-thin layers (AUTL)

This is an Accepted Manuscript of an article published by Taylor & Francis Group in International Journal of Pavement Engineering on 2023, available online at: http://www.tandfonline.com/10.1080/10298436.2023.2241108.The growing use of ultra-thin layers, called AUTL (Asphalt Ultra-Thin Layer), has raised the question of whether the currently used characterisation tests are equally applicable to mixes that are spread in such small thicknesses (10–20 mm). Among these tests are the shear tests mainly used for evaluating adhesion between layers. The guillotine type clamps, used in the tests such as the Leutner or any of its adaptations, can present problems when performing the test with thicknesses under 20 mm, so many regulations require minimum layer thicknesses. The aim of this study is to determine whether this type of test is still valid when one of the layers is thin or whether there are other tests that can be used in this case. For this, five different test types are considered: the usual shear test, a tensile test, an adaptation of the Fenix test, a torsion test and a fatigue test. This paper presents a description of these tests, as well as the results obtained with each of them after testing the cores extracted from a test section. The results demonstrate that all the tests can be valid and are capable of discriminating between the different tack coat dosages.Peer ReviewedPostprint (author's final draft

The Parkinson's Disease Sleep Scale–2 (PDSS‐2): Validation of the Spanish Version and Its Relationship With a Roommate‐Based Version

ABSTRACT Background Because of the prevalence and impact of sleep disorders in Parkinson's disease (PD), valid instruments for their evaluation and monitoring are necessary. However, some nocturnal sleep disorders may go unnoticed by patients themselves. Objectives To validate a pan‐Spanish version of the Parkinson's Disease Sleep Scale Version 2 (PDSS‐2) and to test the relationships between the PDSS‐2 and a PDSS‐2 roommate version. Methods PD patients (n = 399) from seven Spanish‐speaking countries were included. In addition to the tested PDSS‐2 scales, valid measures for sleep disorders and both motor and nonmotor manifestations were applied. Acceptability, dimensionality, reliability, precision, and construct validity were explored, as well as discrepancies and agreement between the PDSS‐2 and the roommate version. Results PDSS‐2 showed negligible floor and ceiling effects. Four factors (57% of the variance) were identified. Reliability parameters were satisfactory: alpha = 0.84; item homogeneity coefficient = 0.27; corrected item total correlation = 0.28 to 0.61; and test‐retest reliability (average kappa = 0.70; intraclass correlation coefficient [ICC] = 0.83). The standard error of measurement was 5.84, and correlations with other scales assessing nocturnal sleep were high (rS = 0.62–0.56). In comparison to the patient‐based total score, the by proxy total score showed no significant difference, high correlation (rS = 0.70), and acceptable agreement (ICC = 0.69), but there were discrepancies in two or more points in 18% of item scores. Conclusions The Spanish version of the PDSS‐2 has shown satisfactory clinimetric attributes. Acceptability and precision data are presented for the first time. The PDSS‐2 roommate version could be useful to complement the patient‐based evaluation, but additional studies are needed

Bilateral staged magnetic resonance-guided focused ultrasound thalamotomy for the treatment of essential tremor: a case series study

BACKGROUND Unilateral magnetic resonance-guided focused ultrasound (FUS) thalamotomy is efficacious for the treatment of medically refractory essential tremor (ET). Viability of bilateral FUS ablation is unexplored. METHODS Patients diagnosed with medically refractory ET and previously treated with unilateral FUS thalamotomy at least 5 months before underwent bilateral treatment. The timepoints were baseline (before first thalamotomy) and FUS1 and FUS2 (4 weeks before and 6 months after second thalamotomy, respectively). The primary endpoint was safety. Efficacy was assessed through the Clinical Rating Scale for Tremor (CRST), which includes subscales for tremor examination (part A), task performance (part B) and tremor-related disability (part C). RESULTS Nine patients were treated. No permanent adverse events were registered. Six patients presented mild gait instability and one dysarthria, all resolving within the first few weeks. Three patients reported perioral hypoesthesia, resolving in one case. Total CRST score improved by 71% from baseline to FUS2 (from 52.3±12 to 15.5±9.4, p<0.001), conveying a 67% reduction in bilateral upper limb A+B (from 32.3±7.8 to 10.8±7.3, p=0.001). Part C decreased by 81% (from 16.4±3.6 to 3.1±2.9, p<0.001). Reduction in head and voice tremor was 66% (from 1.2±0.44 to 0.4±0.54, p=0.01) and 45% (from 1.8±1.1 to 1±0.8, p=0.02), respectively. CONCLUSION Bilateral staged FUS thalamotomy for ET is feasible and might be safe and effective. Voice and head tremor might also improve. A controlled study is warranted