Understanding the influence of filler type and asphalt binder content on the moisture and fatigue resistance of asphalt mortars

An adequate moisture resistance is a key element to guarantee the durability of asphalt materials. This paper identifies the influence of filler typology and bitumen content on the mechanical response of asphalt mortars before and after water action. Two fillers were evaluated: Portland cement and Calcium carbonate, along with different contents of a penetration bitumen (B35/50). Stiffness, ductility, and fatigue were evaluated through a new protocol for asphalt mortar samples using a 3-point-bending test on DMA (Dynamic Mechanical Analyzer). The use of Portland cement presents higher stiffness, lower ductility, and improved fatigue and water resistance compared to Calcium carbonate. It is also possible to optimize bitumen content based on fatigue results. Content beyond the optimal reduce variations after water action but compromise fatigue resistance. Lower content leads to a poorer performance in both terms. This methodology enables asphalt mortar characterisation as a tool to optimise the design of asphalt materials.La influencia del tipo de polvo mineral y contenido de ligante bituminoso en la resistencia a la humedad y fatiga de morteros bituminosos. La resistencia al agua es clave para garantizar la durabilidad de los materiales asfálticos. Este estudio identifica la influencia del polvo mineral y contenido de betún en la respuesta mecánica de morteros bituminosos antes y después de la humedad. Se evaluaron dos tipos de filler: cemento Portland y carbonato cálcico (filler calizo), junto con distintos contenidos de betún (B35/50). Rigidez, ductilidad y fatiga fueron evaluados mediante un nuevo ensayo de fatiga a tres puntos para morteros empleando DMA (Dynamic Mechanical Analyzer). El cemento presenta más rigidez, menos ductilidad y mayor resistencia al agua y fatiga que el filler calizo. Los resultados de fatiga permiten además optimizar el contenido de betún. Contenidos por encima del óptimo reducen variaciones tras la humedad pero comprometen la resistencia a fatiga. Contenidos menores conllevan un peor comportamiento en ambos términos. Esta metodología permite usar la caracterización de morteros bituminosos para optimizar el diseño de materiales asfálticos

Accuracy and Survival Outcomes after National Implementation of Sentinel Lymph Node Biopsy in Early Stage Endometrial Cancer

Background. Sentinel lymph node (SLN) biopsy has recently been accepted to evaluate nodal status in endometrial cancer at early stage, which is key to tailoring adjuvant treatments. Our aim was to evaluate the national implementation of SLN biopsy in terms of accuracy to detect nodal disease in a clinical setting and oncologic outcomes according to the volume of nodal disease. Patients and Methods. A total of 29 Spanish centers participated in this retrospective, multicenter registry including patients with endometrial adenocarcinoma at preoperative early stage who had undergone SLN biopsy between 2015 and 2021. Each center collected data regarding demographic, clinical, histologic, therapeutic, and survival characteristics. Results. A total of 892 patients were enrolled. After the surgery, 12.9% were suprastaged to FIGO 2009 stages III-IV and 108 patients (12.1%) had nodal involvement: 54.6% macrometastasis, 22.2% micrometastases, and 23.1% isolated tumor cells (ITC). Sensitivity of SLN biopsy was 93.7% and false negative rate was 6.2%. After a median follow up of 1.81 years, overall surivial and disease-free survival were significantly lower in patients who had macrometastases when compared with patients with negative nodes, micrometastases or ITC. Conclusions. In our nationwide cohort we obtained high sensitivity of SLN biopsy to detect nodal disease. The oncologic outcomes of patients with negative nodes and low-volume disease were similar after tailoring adjuvant treatments. In total, 22% of patients with macrometastasis and 50% of patients with micrometastasis were at low risk of nodal metastasis according to their preoperative risk factors, revealing the importance of SLN biopsy in the surgical management of patients with early stage EC

The Influence of Reclaimed Asphalt Pavement on the Mechanical Performance of Bituminous Mixtures. An Analysis at the Mortar Scale

The main characteristics of bituminous mixtures manufactured with a considerable amount of reclaimed asphalt pavement (RAP), compared to conventional mixtures, are a reduction in workability, an increase in stiffness, and a loss of ductility, due to the presence of the aged bitumen contained in the RAP particles. To minimize these impacts, softer binders or rejuvenators are commonly used in the design of these mixtures in order to restore part of the ductility lost and to reduce the stiffness. In spite of previous investigations demonstrating that the mortar plays an essential role in the workability, long-term performance, and durability of bituminous mixtures (where cracking, cohesion, and adhesion problems all start at this scale), not many studies have assessed the impacts caused by the presence of RAP. In response to this, the present paper analyzes the workability, fatigue performance, and water sensitivity of bituminous mortars containing different amounts of RAP (from 0% to 100%) and rejuvenators. Mortar specimens were compacted using a gyratory compactor and studied via dynamic mechanical analysis under three point bending configuration. The results demonstrated that the presence of RAP reduces the workability and ductility of asphalt mortars. However, it also causes an increase in their stiffness, which induces a more elastic response and causes an increase in their resistance to fatigue, which could compensate for the loss of ductility. This aspect, together with the low water sensitivity shown, when using Portland cement as an active filler, would make it possible to produce asphalt materials with high RAP contents with a similar long-term mechanical performance as traditional ones. In addition, the use of rejuvenators was demonstrated to effectively correct the negative workability and ductility impacts caused by using RAP, without affecting the fatigue resistance and material adhesion/cohesion

Low entropy map of brain oscillatory activity identifies spatially localized events

The spatial mapping of localized events in brain activity critically depends on the correct identification of the pattern signatures associated with those events. For instance, in the context of epilepsy research, a number of different electrophysiological patterns have been associated with epileptogenic activity. Motivated by the need to define automated seizure focus detectors, we propose a novel data-driven algorithm for the spatial identification of localized events that is based on the following rationale: the distribution of emerging oscillations during confined events across all recording sites is highly non-uniform and can be mapped using a spatial entropy function. By applying this principle to EEG recording obtained from 67 distinct seizure epochs, our method successfully identified the seizure focus on a group of ten drug-resistant temporal lobe epilepsy patients (average sensitivity: 0.94, average specificity: 0.90) together with its characteristic electrophysiological pattern signature. Cross-validation of the method outputs with postresective information revealed the consistency of our findings in long follow-up seizure-free patients. Overall, our methodology provides a reliable computational procedure that might be used as in both experimental and clinical domains to identify the neural populations undergoing an emerging functional or pathological transition.M.V was supported by a fellowship from ”la Caixa” Foundation, Spain (ID 100010434, fellowship code LCF/BQ/DE17/11600022). G.D. ​was ​supported by the ​Spanish Ministry of Economy and Competitiveness, Spain (grant agreement number ​PSI2016-75688-P, MINECO/AEI/FEDER-EU); European Union’s Horizon 2020 FET Flagship Human Brain Project (grant agreement number 785907, HBP SGA2); the Catalan Agency for Management of University and Research Grants, Spain (grant agreement number 2017 SGR 1545), and the Swiss National Science Foundation, Switzerland ​(grant agreement number ​CRSII5_170873)

Reclaimed Polymers as Asphalt Binder Modifiers for More Sustainable Roads: A Review

The use of polymer-modified binders in asphalt mixtures has become more widespread due to their reduced thermal susceptibility and improved rutting and fatigue resistance. Nevertheless, their high cost limits their application, thus making the use of reclaimed polymers (RP) an interesting alternative for both reducing price and extending the service life of pavements. This paper; therefore, presents a comparative review of the recycled polymers most commonly studied as bitumen modifiers: polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), ethyl vinyl acetate (EVA), and ground tire rubber (GTR), in order to facilitate their selection and extend the use of the bitumen. The differences in terms of melting point, mixing conditions, and maximum quantity of added polymer are analyzed. Moreover, their effect on the mechanical behavior of the asphalt binders and their stability with and without the use of additives is presented. According to the literature revision, the performance of the new binder is more influenced by the kind of polymer that was incorporated and the mixing conditions than by the base bitumen that was chosen, although rheological evaluation is needed to fully understand the modification mechanisms of the modified binder. In general terms, plastomers have a stronger effect in terms of increasing the stiffness of the bitumen in comparison with crumb rubber (elastomers), thus providing an improved rutting resistance. The joint use of polyethylene (plastomer) and crumb rubber (elastomer) can be an interesting option for its recycling potential and mechanical performance, although further study is needed to achieve stable bitumen across the entire range of temperatures; additives, such as maleic anhydride (MA), are commonly employed to improve the stability of the binder and enhance its characteristics, but their use could limit the economic benefits of using recycled materials

Integración : revista sobre ceguera y deficiencia visual

Resumen tomado de la publicación. El trabajo obtuvo el primer premio del 'XIII Concurso de Investigación Educativa sobre Experiencias Escolares', convocado en 1999 por la ONCESe presenta una experiencia docente para alumnos de educación integrada (ciegos y videntes), basada en la adaptación de la ópera La flauta mágica, de Mozart. Se indican los objetivos generales y específicos, los contenidos, y se describen los materiales: el libro con la adaptación del libreto, con ilustraciones en relieve, objetos manipulables y texturas significativas; un cuaderno de ejercicios; una guía didáctica para el profesor; y un CD-ROM con los fragmentos musicales y el enunciado de las preguntas del cuaderno de ejercicios. Se refiere el desarrollo de las sesiones y se plantean orientaciones pedagógicas para el profesorado de música.MadridUniversidad de Salamanca. Facultad de Educación; Paseo Canalejas, 169; 37008 Salamanca; Tel. +34923294630; +34923294609; [email protected]

Influence of Type of Filler and Bitumen on the Mechanical Performance of Asphalt Mortars

This article presents a new methodology of analysis based on a fast-running experimental procedure to characterise the mechanical response of asphalt mortars in terms of stiffness, ductility, and fatigue resistance. This was achieved using the DMA (Dynamic Mechanical Analyser) threepoint bending configuration. The study was carried out by considering the employment of different types of fillers such cement and CaCO3 and different types of binders such as conventional asphalt binder (B35/50) or modifided polymer-modified bitumen (PMB 25/55–65). From the results of this study, the filler was found to have a greater influence on the stiffness and ductility of the asphalt material, while bitumen had a higher effect on the fatigue life of the asphalt mortar. Fatigue life was observed to increase with the use of a polymer-modified binder, while a lower degree of permanent deformation and higher bearing capacity achieved by the use of cement instead of calcium carbonate as active fillers

Impact of uterine manipulator on oncological outcome in endometrial cancer surgery.

There are limited data available to indicate whether oncological outcomes might be influenced by the uterine manipulator, which is used at the time of hysterectomy for minimally invasive surgery in patients with endometrial cancer. The current evidence derives from retrospective studies with limited sample sizes. Without substantial evidence to support its use, surgeons are required to make decisions about its use based only on their personal choice and surgical experience. To evaluate the use of the uterine manipulator on oncological outcomes after minimally invasive surgery, for apparent early-stage endometrial cancer. We performed a retrospective multicentric study to assess the oncological safety of uterine manipulator use in patients with apparent early-stage endometrial cancer, treated with minimally invasive surgery. The type of manipulator, surgical staging, histology, lymphovascular space invasion, International Federation of Gynecology and Obstetrics stage, adjuvant treatment, recurrence, and pattern of recurrence were evaluated. The primary objective was to determine the relapse rate. The secondary objective was to determine recurrence-free survival, overall survival, and the pattern of recurrence. A total of 2661 women from 15 centers were included; 1756 patients underwent hysterectomy with a uterine manipulator and 905 without it. Both groups were balanced with respect to histology, tumor grade, myometrial invasion, International Federation of Gynecology and Obstetrics stage, and adjuvant therapy. The rate of recurrence was 11.69% in the uterine manipulator group and 7.4% in the no-manipulator group (P In this study, the use of a uterine manipulator was associated with a worse oncological outcome in patients with uterus-confined endometrial cancer (International Federation of Gynecology and Obstetrics I-II) who underwent minimally invasive surgery. Prospective trials are essential to confirm these results

Lymphovascular Space Invasion in Early-Stage Endometrial Cancer (LySEC): Patterns of Recurrence and Predictors. A Multicentre Retrospective Cohort Study of the Spain Gynecologic Oncology Group

The main aim is to compare oncological outcomes and patterns of recurrence of patients with early-stage endometrioid endometrial cancer according to lymphovascular space invasion (LVSI) status. The secondary objective is to determine preoperative predictors of LVSI. We performed a multicenter retrospective cohort study. A total of 3546 women diagnosed with postoperative early-stage (FIGO I-II, 2009) endometrioid endometrial cancer were included. Co-primary endpoints were disease-free survival (DFS), overall survival (OS), and pattern of recurrence. Cox proportional hazard models were used for time-to-event analysis. Univariate and multivariate logistical regression models were employed. Positive LVSI was identified in 528 patients (14.6%) and was an independent prognostic factor for DFS (HR 1.8), OS (HR 2.1) and distant recurrences (HR 2.37). Distant recurrences were more frequent in patients with positive LVSI (78.2% vs. 61.3%, p < 0.01). Deep myometrial invasion (OR 3.04), high-grade tumors (OR 2.54), cervical stroma invasion (OR 2.01), and tumor diameter ≥ 2 cm (OR 2.03) were independent predictors of LVSI. In conclusion, in these patients, LVSI is an independent risk factor for shorter DFS and OS, and distant recurrence, but not for local recurrence. Deep myometrial invasion, cervical stroma invasion, high-grade tumors, and a tumor diameter ≥ 2 cm are independent predictors of LVSI