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Activation of autogenous self-healing in pozzolanic natural hydraulic self-compacting lime concrete under cyclic compressive loading
No full textThis study investigates the activation of autogenous self-healing in pozzolanic natural hydraulic lime concrete subjected to cyclic compressive loading. Several concrete mixtures were formulated incorporating various mineral pozzolanic additions, including one reinforced with steel fibers, to evaluate their influence on fatigue performance and healing capacity. Fatigue tests revealed significant variability in the fatigue life of specimens, effectively modeled by the Weibull distribution. Fibers did not reduce fatigue life variability nor produce surviving specimens after testing, despite their expected role in crack control and damage stabilization. Mixes with runout specimens exhibited greater scatter in fatigue life, with cyclic loading inducing notable self-healing in specific lime-based concretes, particularly in the metakaolin-enriched mixture. Runout specimens from this mix showed marked increases in compressive strength and stiffness, confirming successful autogenous healing. The strain-cycle behavior displayed stable secondary strain phases, which correlated with fatigue life through a log–log relationship, highlighting the interaction between microstructural damage and healing. Microstructural analyses using thermal techniques – thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) – as well as X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP), provided comprehensive insights into the self-healing mechanisms. TGA–DSC results demonstrated increased calcium carbonate and portlandite contents in specimens subjected to higher fatigue cycles, supporting self-healing through carbonation, hydration, and rehydration. XRD identified crystalline phases linked to ongoing hydration and carbonation reactions, while MIP revealed densification of the pore network, contributing to enhanced mechanical properties. These processes facilitate crack filling and matrix consolidation, improving stiffness and strength retention over time. The findings suggest that fatigue-induced microcracking primarily activates carbonation reactions, supplemented by hydration, resulting in progressive microstructural recovery and durability enhancement under cyclic loading. This work underscores the potential of combining pozzolanic additives and cyclic mechanical loading to promote sustainable, low-carbon lime-based concretes with intrinsic self-healing capabilities. Such materials are promising for eco-efficient construction and the restoration of heritage structures, providing increased lifespan and reduced maintenance needs.This research was funded by the Ministerio de Innovación, Ciencia
Universidades, Spain, through grant PID2023-147971OB-C31, the Junta de Comunidades de Castilla-La Mancha, Spain, through grant SBPLY/24/180225/000003, and Universidad de Castilla-La Mancha & ERDF through grant 2025-GRIN-38445
Immunogenicity, effectiveness and safety of COVID-19 vaccine in older adults living in nursing homes: A real-life study [Inmunogenicidad, efectividad y seguridad de la vacuna COVID-19 en adultos mayores que viven en hogares geriátricos: un estudio de la vida real]
No full textIntroduction: BNT162b2 (BioNTech and Pfizer) is a nucleoside-modified mRNA vaccine that provides protection against SARS-CoV-2 infection and is generally well tolerated. However, data about its efficacy, immunogenicity and safety in people of old age or with underlying chronic conditions are scarce. Purpose: To describe BNT162b2 (BioNTech and Pfizer) COVID-19 vaccine immunogenicity, effectiveness and reactogenicity after complete vaccination (two doses), and immunogenicity and reactogenicity after one booster, in elders residing in nursing homes (NH) and healthy NH workers in real-life conditions. Methods: Observational, ambispective, multicenter study. Older adults and health workers were recruited from three nursing homes of a private hospital corporation located in three Spanish cities. The primary vaccination was carried out between January and March 2021. The follow-up was 13 months. Humoral immunity, adverse events, SARS-CoV-2 infections, hospitalizations and deaths were evaluated. Cellular immunity was assessed in a participant subset. Results: A total of 181 residents (mean age 84.1 years; 89.9% females, Charlson index ?2: 45%) and 148 members of staff (mean age 45.2 years; 70.2% females) were surveyed (n:329). After primary vaccination of 327 participants, vaccine response in both groups was similar; ?70% of participants, regardless of the group, had an antibody titer above the cut-off considered currently protective (260 BAU/ml). This proportion increased significantly to ? 98% after the booster (p < 0.0001 in both groups). Immunogenicity was largely determined by a prior history of COVID-19 infection. Twenty residents and 3 workers were tested for cellular immunity. There was evidence of cellular immunity after primary vaccination and after booster. During the study, one resident was hospitalized for SARS-CoV-2. No SARS-CoV-2-related deaths were reported and most adverse events were mild. Conclusions: Our results suggest that the BNT162b2 mRNA COVID-19 vaccine is immunogenic, effective and safe in elderly NH residents with underlying chronic conditions. © 2023 SEG
Neuronize: a tool for building realistic neuronal cell morphologies
No full textThis study presents a tool, Neuronize, for building realistic three-dimensional models of neuronal cells from the morphological information extracted through computer-aided tracing applications. Neuronize consists of a set of methods designed to build 3D neural meshes that approximate the cell membrane at different resolution levels, allowing a balance to be reached between the complexity and the quality of the final model. The main contribution of the present study is the proposal of a novel approach to build a realistic and accurate 3D shape of the soma from the incomplete information stored in the digitally traced neuron, which usually consists of a 2D cell body contour. This technique is based on the deformation of an initial shape driven by the position and thickness of the first order dendrites. The addition of a set of spines along the dendrites completes the model, building a final 3D neuronal cell suitable for its visualization in a wide range of 3D environment
Uso de role playing y pódcast para promover la empatía como propuesta de innovación en el Grado en Enfermería. Formación en valores
No full textLa formación universitaria en Ciencias de la Salud debe equilibrar los contenidos científico técnicos con la formación en humanización asistencial. Esta perspectiva humanizadora está íntimamente relacionada con la capacidad de los profesionales de empatizar con los pacientes. Se llevó a cabo una actividad de innovación educativa mediante role playing basado en investigación cualitativa y pódcast, con el objetivo de fomentar en el estudiantado la empatía como fuente de humanización en dos asignaturas del Grado en Enfermería. Se evaluó el grado de empatía mediante la escala JSE-HPS realizando un análisis pre-post, y mediante un análisis cualitativo temático a partir de los datos de un cuestionario abierto de satisfacción y un grupo focal. Los resultados mostraron un aumento del nivel de sensibilidad empática y un alto grado de satisfacción con las herramientas, el aprendizaje profesional y personal. Se puede concluir que la actividad ha sido útil y fácilmente aplicable y replicable
Longitudinal Correlates of Depressive Symptoms and Positive and Negative Affects in Family Caregivers of People With Dementia
No full textObjective: Caring for a relative with dementia is considered a chronically stressful role associated with negative consequences for psychological health such as higher levels of depression. However, the subjective experience of depressive symptomatology is complex as it relates to two unique domains: positive affect (PA) and negative affect (NA). The objective of this study was to analyze, through a longitudinal design, the associations of caregivers' cognitive (avoidance coping, personal master)), and coping self-efficacy) and behavioral (frequency of pleasant events) coping strategies with depressive symptoms, PA, and NA. Methods: A total of 111 caregivers of a spouse with dementia participated in this study. They were assessed yearly across 5 years. Mixed model regression analyses were conducted separately for depressive symptoms, PA, and NA, analyzing within and between-person associations of caregivers' age, gender, role overload, sleep quality, and coping variables previously mentioned. Results: The results showed that different coping strategies were associated with different components of depressive symptomatology. While avoidant coping was associated with NA and depressive symptoms but not PA at both within- and between-person levels, frequency of pleasant events was associated only with NA and depressive symptoms at the within-person level, showing no effect at the between-person level. Personal mastery and coping self-efficacy were found to be more transversal variables, being associated with most of the mood outcomes in both within and between-person effects. Conclusion: Findings support the concept of depressive mood as a complex construct and highlights the importance of analyzing different coping strategies when trying to comprehend the caregiving stress process
Voxel Change: Big Data-Based Change Detection for Aerial Urban LiDAR of Unequal Densities
No full textThe proposed voxel change (VC) algorithm provides accurate, scalable, and quantifiable change detection for urban aerial Light Detection and Ranging (LiDAR) scans. This VC algorithm uses MapReduce, a big data programming model, to map neighboring points into cubes. The algorithm converts each data set into a group of cubes, and classifies them into categories of building, ground, or vegetation. It then compares and quantifies changes in area or volume. Spatial discontinuity is overcome by clustering. Quality metrics are demonstrated by comparing a 1 km(2) data set of Dublin, Ireland, using a 2007 scan with a point density of 225 points per square meter (pts/m(2)) and a 2015 scan with 335 pts/m(2) (totaling more than 500 million points). By using only positional LiDAR information as the data input, the quality metric exceeded 90% across the full data set with respect to lost, new, and unchanged designations for vegetation, buildings, and ground areas, and regularly exceeded 98% for buildings. The technique successfully processes nonrectilinear features and robustly provides a quantification of change for both building expansion and vegetation at a 1 m(3) level using dense, modern data sets. (C) 2021 American Society of Civil Engineers
Enamel cracks and dental bleaching: does a gingival barrier reduce hydrogen peroxide penetration?
No full textObjectives: To evaluate hydrogen peroxide (HP) penetration into teeth with enamel cracks and to assess the effectiveness of a gingival barrier as a protective strategy. Additionally, the study examined whether the use of a gingival barrier affects bleaching efficacy. Materials and Methods: Thirty human premolars (n = 10 per group) were allocated into three experimental groups: intact teeth, teeth with enamel cracks, and teeth with enamel cracks protected with a gingival barrier. Cracks were detected using transillumination and measured using ImageJ software. In the third group, the gingival barrier was applied directly over the cracks, and the buccal surface of all specimens was also isolated with a gingival barrier (6 mm radius) and light-cured for 30 s. Bleaching was performed with 35 % hydrogen peroxide in two 30-minute sessions, with a seven-day interval apart. HP penetration into the pulp chamber was quantified using UV-Vis spectrophotometry. Bleaching efficacy was assessed by digital spectrophotometry (Delta E00 and Delta WID). Data were analyzed using one-way and two-way ANOVA (alpha = 0.05). Results: Teeth exhibited vertical cracks averaging 4.2 +/- 1.3 mm in length. Cracked teeth demonstrated 35 % higher HP penetration compared to intact teeth (p < 0.05). Covering the cracks with a gingival barrier did not reduce HP penetration (p = 0.22). No significant differences were found in bleaching efficacy among the groups (p > 0.05). Conclusions: Enamel cracks significantly increased HP penetration. The gingival barrier did not reduce diffusion but did not compromise bleaching efficacy. Clinical Relevance: Teeth presenting enamel cracks showed significantly increased hydrogen peroxide penetration. Alternative protective strategies should be explored, as gingival barriers alone appear insufficient to effectively seal enamel cracks
Two rare species of tylenchids, Discotylenchus biannulatus n. sp and Labrys chinensis Qing & Bert, 2018 (Nematoda: Tylenchidae) from western Iran
No full textTwo rare species of the family Tylenchidae are described and illustrated based on morphological and morphometric characters. Scanning electron microscope (SEM) studies provided details of anterior end structures, helpful in generic identification of the studied populations. Discotylenchus biannulatus n. sp. is characterized by its dorso-ventrally flattened smooth cephalic region having two proximal annuli and a rectangular perioral disc, short longitudinal amphidial slits, lateral field with four incisures, stylet 9-10 mu m long, with the conus shorter than half the total stylet length and with posteriorly directed knobs, well-developed median bulb, mono-prodelphic reproductive system with rounded empty spermatheca and short postvulval uterine sac (PUS), and filiform tail with pointed end. It is compared with other species of Discotylenchus having four lines in the lateral field. The Iranian population of Labrys chinensis is characterized by its long and slender (a = 45.2-57.2) body, smooth rounded cephalic region and an offset disc-like apical labial plate, short longitudinal lateral amphidial slits, lateral field with two incisures, moderately developed stylet with the conus less than half the total length and posteriorly directed knobs, median bulb fusiform with distinct but weak valve, gradually joining the isthmus, vulva at 57.2-59.1% with small flaps, elongate conoid tail, uniformly and slightly narrowing toward end with broadly rounded terminus and rare males. The minor morphological differences of the recovered population with the type population are discussed
Morphological and molecular characterization of two new species of the genus Aporcelinus Andrassy, 2009 (Nematoda, Dorylaimida, Aporcelaimidae) from the USA, with new insights on the phylogeny of the genus
No full textTwo new species of the genus Aporcelinus from the USA are described and illustrated. Aporcelinus floridensis sp. n. is characterized by its 1.12-1.52mm long body, lip region offset by marked constriction and 14.5-17.0 mu m broad with perioral liplets, odontostyle 16.5-20.0 mu m at its ventral side and 1.1-1.2 times the lip region diameter, neck 316-395 mu m long, pharyngeal expansion occupying 43-48% of total neck length, uterus simple and 33-56 mu m long or 0.8-1.2 times the corresponding body diameter, V = 48-54, female tail conical (36-49 mu m long, c = 27-41, c' = 1.2-2.0) with finely rounded terminus and no hyaline portion, and male absent. Aporcelinus paolae sp. n. is characterized by its 1.29-1.80mm long body, lip region offset by marked constriction and 14-16 mu m broad, odontostyle 15-17 mu m at its ventral side and 1.0-1.1 times the lip region diameter, neck 314-397 mu m long, pharyngeal expansion occupying 43-53% of total neck length, uterus tripartite and 128-164 mu m long or 2.6-3.6 times the corresponding body diameter, V = 53-57, female tail conical (30-39 mu m long, c = 40-51, c' = 1.1-1.3) with finely rounded terminus and variably re-curved dorsad, male tail conical (27-36 mu m, c = 39-59, c' = 0.9-1.2), ventrally straight and dorsally convex, spicules 48-54 mu m long, and 7-9 irregularly spaced ventromedian supplements lacking hiatus. The analyses of the D2-D3 expansion segments of 28S rRNA (LSU) gene sequences of the two new species confirmed the monophyly of the genus, based upon currently available data, showing a close relationship between the genera Aporcelinus and Makatinus, and justified the placement of Aporcelaimellus, Makatinus and Aporcelinus under the subfamily Aporcelaimellinae
Attention and impulsivity assessment using virtual reality games
No full textThe assessment of cognitive functions is mainly based on standardized neuropsychological tests, widely used in various fields such as personnel recruitment, education, or health. This paper presents a virtual reality game that allows collecting continuous measurements of both the performance and behaviour of the subject in an immersive, controllable, and naturalistic experience. The application registers variables related to the user’s eye movements through the use of virtual reality goggles, as well as variables of the game performance. We study how virtual reality can provide data to help predict scores on the Attention Control Scale Test and the Barratt Impulsiveness Scale. We design the application and test it with a pilot group. We build a random forest regressor model to predict the attention and impulsivity scales’ total score. When evaluating the performance of the model, we obtain a positive correlation with attention (0.434) and with impulsivity (0.382). In addition, our model identified that the most significant variables are the time spent looking at the target or at distractors, the eye movements variability, the number of blinks and the pupil dilation in both attention and impulsivity. Our results are consistent with previous results in the literature showing that it is possible to use data collected in virtual reality to predict the degree of attention and impulsivity