Some experimental observations of crack-tip mechanics with displacement data

Estudio de la mecánica en el vértice de la grieta mediante datos de desplazamiento.In the past two decades, crack-tip mechanics has been increasingly studied with full-field techniques. Within these techniques, Digital Image Correlation (DIC) has been most widely used due to its many advantages, to extract important crack-tip information, including Stress Intensity Factor (SIF), Crack Opening Displacement, J-integral, T-stress, closure level, plastic zone size, etc. However, little information is given in the literature about the experimental setup that provides best estimations for the different parameters. The current work aims at understanding how the experimental conditions used in DIC influence the crack-tip information extracted experimentally. The influence of parameters such as magnification factor, size of the images, position of the images with respect the crack-tip and size of the subset used in the correlation is studied. The influence is studied in terms of SIF and T-stress by using Williams’ model. The concept of determination of the K-dominance zone from experimental data has also explored. In this regard, cyclic loading on a fatigue crack in a compact tension (CT) specimen, made of aluminium 2024-T351 alloy, has been applied and the surface deformation ahead of the crack tip has been examined. The comparison between theoretical and experimental values of KI showed that the effect of subset size on the measured KI is negligible compared to the effect of size of the image.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Experimental and analytical study of cracks under biaxial fatigue

Most mechanical components experience multi-axial cyclic loading conditions during service. Experimental analysis of fatigue cracks under such conditions is not easy and most works tend to focus more on the simpler but less realistic case of uni-axial loading. Consequently, there are many uncertainties related to the load sequence effect that are now well known and are not normally incorporated into the growth models. The current work presents a new methodology for evaluating overload effect in biaxial fatigue cracks. The methodology includes evaluation of mixed-mode (KI and KII) stress intensity factor and the Crack Opening Displacement for samples with and without overload cycle under biaxial loading. The methodology is tested under a range of crack lengths. All crack-tip information is obtained with a hybrid methodology that combines experimental full-field digital image correlation data and Williams' elastic model describing the crack-tip field.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Diagnostic concordance of DSM-IV and DSM-5 Posttraumatic Stress Disorder (PTSD) in a clinical sample

The present study aims to analyze diagnostic concordance between the DSM-IV and the DSM-5 for posttraumatic stress disorder (PTSD) diagnostic criteria and their different groups of symptoms. Furthermore, analyses are conducted to establish the features of participants with no concordant diagnoses. Method: The study assessed 166 people over 18 who had experienced at least one traumatic event. PTSD diagnosis was established using the Global Scale for Posttraumatic Stress (EGEP), a self-report measure to assess PTSD. Results: The presence of cognitive avoidance was a determinant in the PTSD DSM-5 diagnosis (86% positive predictive value). The analysis of the non-concordant individuals revealed that individuals who were diagnosed according to the DSM-IV criteria but not the DSM-5 criteria were primarily indirect victims. Conversely, individuals who were diagnosed with the DSM-5 criteria and not with the DSM-IV criteria presented cognitive avoidance and alterations in cognition not included in the DSM-IV criteria. Conclusions: A withinsubjects concordance analysis showed high agreement for PTSD diagnosis between the two classifi cations. Differences between the diagnoses are due to the new defi nition of C (avoidance) and D (negative alterations in cognitions and mood) in the DSM-

Phosphorus Availability Regulates TORC1 Signaling via LST8 in Chlamydomonas

Target of rapamycin complex 1 (TORC1) is a central regulator of cell growth. It balances anabolic and catabolic processes in response to nutrients, growth factors, and energy availability. Nitrogen- and carbon-containing metabolites have been shown to activate TORC1 in yeast, animals, and plants. Here, we show that phosphorus (P) regulates TORC1 signaling in the model green alga Chlamydomonas (Chlamydomonas reinhardtii) via LST8, a conserved TORC1 subunit that interacts with the kinase domain of TOR. P starvation results in a sharp decrease in LST8 abundance and downregulation of TORC1 activity. A hypomorphic lst8 mutation resulted in decreased LST8 abundance, and it both reduced TORC1 signaling and altered the cellular response to P starvation. Additionally, we found that LST8 levels and TORC1 activity were not properly regulated in a mutant defective in the transcription factor PSR1, which is the major mediator of P deprivation responses in Chlamydomonas. Unlike wild-type cells, the psr1 mutant failed to downregulate LST8 abundance and TORC1 activity when under P limitation. These results identify PSR1 as an upstream regulator of TORC1 and demonstrate that TORC1 is a key component in P signaling in Chlamydomonas.España Ministerio de Economía y Competitividad (grants BFU2015-68216-P and PGC2018-099048- B-100 to J.L.C. and grant BIO2015-74432-JIN to M.E.P.-P.)National Science Foundation (CAREER award MCB-1552522 to L.M.H. and grant MCB-1616820 to J.G.U.)European Commission (grant number 750996

Origins of empathy development in infancy

The current thesis examined the processes involved in the generation of empathy in infancy. This thesis endorses the combination of developmental and cognitive neuroscience techniques for a more comprehensive understanding of empathy. In support of this view, the current work has adopted a multi-method approach in which neuroimaging, psychophysiological and behavioral techniques have been used to examine the cognitive and affective aspects of empathy in infancy. Through a series of experimental studies, this thesis has addressed intertwined yet different aspects of the experience of empathy. Paper 1 investigated individual differences in 8-month-old infants’ neural responses to peers’ emotional non-verbal vocalizations by using event-related potential (ERP) method and parental reports of infants’ temperament. Results showed that infants responded differently to peers’ laughing and crying vocalizations, as indexed by modulations in the N100, P200 and late positive component (LPC). Of special interest, individual differences in negative emotionality were related to amplitude variations in the P200 and LPC components. Paper 2 expands on the previous results by examining frontal asymmetry patterns linked to infants’ affective and behavioral responses to a peer crying and a peer laughing. Eight-month-old infants underwent two assessment sessions on separate days, in which electroencephalography (EEG) and behavioral measures were respectively recorded in each day. EEG analysis showed that distinct neural patterns were related to the observation of a peer laughing and a peer crying, with greater right frontal activation being associated with the observation of a peer crying. Furthermore, correlational analysis suggested a positive relation between left frontal cortical activation and infants’ attempts to approach a peer crying or infants’ attempts to engage with a peer laughing. Following on from it, Paper 3 and 4 investigated potential neurocognitive mechanisms underlying affective and cognitive aspects of empathy. Paper 3 examined the role of motor mimicry and affective evaluation processes in infants’ facial matching responses to others’ emotional facial expressions by measuring spontaneous facial reactions (SFRs). In particular, 4- and 7-month old infants were presented with facial expressions of happiness, anger, and fear. Electromyography (EMG) was used to measure activation in muscles relevant for forming these expressions: zygomaticus major (smiling), corrugator (frowning), and frontalis (forehead raising). Results indicated no selective activation of the facial muscles for the expressions in 4-monthold infants. For 7-month-old infants, evidence for selective facial reactions was found especially for happy faces and fearful faces, while angry faces did not show a clear differential response. Paper 4 goes on to explore the ontogeneis of cognitive aspects of empathy by examining the neural correlates underlying false belief (FB) processing in 15-monthold infants. Using a passive non-verbal FB task, 15-month-old infants were presented with sequences of images depicting a character acting congruently (FBc) or incongruently (FBi) to her false belief about an object’s location, while EEG was continuously recorded. ERPs analysis revealed differences between conditions at frontal locations, as indexed by modulations in the N400 component. Specifically, a more negative N400 waveform was recorded for FBi as compared to FBc trials

Solvent-free process for the development of photocatalytic membranes

PTDC/EAM-AMB/30989/2017.This work described a new sustainable method for the fabrication of ceramic membranes with high photocatalytic activity, through a simple sol-gel route. The photocatalytic surfaces, prepared at low temperature and under solvent-free conditions, exhibited a narrow pore size distribution and homogeneity without cracks. These surfaces have shown a highly efficient and reproducible behavior for the degradation of methylene blue. Given their characterization results, the microfiltration photocatalytic membranes produced in this study using solvent-free conditions are expected to effectively retain microorganisms, such as bacteria and fungi that could then be inactivated by photocatalysis.publishe

Novel submerged photocatalytic membrane reactor for treatment of olive mill wastewaters

POCI-01-0145-FEDER-007265A new hybrid photocatalytic membrane reactor that can easily be scaled-up was designed, assembled and used to test photocatalytic membranes developed using the sol–gel technique. Extremely high removals of total suspended solids, chemical oxygen demand, total organic carbon, phenolic and volatile compounds were obtained when the hybrid photocatalytic membrane reactor was used to treat olive mill wastewaters. The submerged photocatalytic membrane reactor proposed and the modified membranes represent a step forward towards the development of new advanced treatment technology able to cope with several water and wastewater contaminants.publishersversionpublishe

Periodistes, individualisme o corporativisme

Periodistes, individualisme o corporativism

Evaluación de la zona plástica en fatiga para un acero bainitico mediante difracción de rayos x

En este artículo se presenta una nueva metodología para medir la zona plástica de una grieta en fatiga. Se han adquirido datos de difracción de rayos X sincrotrón para una probeta Compact Tension de acero bainítico, en el plano medio a través del espesor. Estos datos han sido traducidos a campos 2D de deformación en torno al vértice. Se ha generado un campo de deformación angular artificial para, en consonancia con los anteriores, obtener el campo de deformación equivalente de Von Mises. La aplicación de la ley de comportamiento elástico ha permitido hallar campos de tensión equivalente entorno al vértice de grieta. Así, se permite estimar la zona plástica y sus dimensiones. Finalmente se estudia la precisión de la metodología a través de una comparación con los modelos de zona plástica de Irwin y de Dugdale.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech Los autores agradecen la financiación aportada para la realización de este trabajo al Ministerio de Economía y Competitividad (referencia MAT2016-76951-C2-2-P) y al Fondo Social Europeo a través de la Iniciativa de Empleo Juvenil (referencia UMAJI84)

Ten years in the dump: An updated review of the Miocene primate-bearing localities from Abocador de Can Mata (NE Iberian Peninsula)

More than ten years of paleontological fieldwork during the enlargement of the Can Mata Landfill (Abocador de Can Mata [ACM]), in els Hostalets de Pierola (Vallès-Penedès Basin, NE Iberian Peninsula) led to the recovery of >60,000 Miocene vertebrate remains. The huge sampling effort (due to continuous surveillance of heavy machinery digging activity, coupled with manual excavation and screen-washing of sediments) enabled generally rare faunal elements such as pliopithecoid and hominoid primates to be found. Thanks to detailed litho-, bio- and magnetostratigraphic controls, accurate dating is possible for all the recovered primate remains from 19 of the 235 localities defined along the 234 m-thick composite stratigraphic sequence of the ACM. Here we report updated estimated (interpolated) ages for these paleontological localities and review the timing of the primate succession in this area. Our results indicate that the whole ACM sequence is late Aragonian in age (MN6 and MN7+8) and includes seven magnetozones that are correlated to subchrons C5Ar.1r to C5r.2r (ca. 12.6 to 11.4 Ma). Great apes (dryopithecines) are first recorded at 12.4-12.3 Ma, but most of the finds (Anoiapithecus, Pierolapithecus and Dryopithecus) cluster between 12.0 and 11.9 Ma, followed by some indeterminate dryopithecine remains between 11.7 and 11.6 Ma. Pliopithecoids first appear at 12.1 Ma, being subsequently represented by Pliopithecus between 11.9 and 11.7 Ma. The small-bodied hominoid Pliobates is the youngest ACM primate, with an estimated age of 11.6 Ma. Although these primates probably overlapped in time, their co-occurrence is recorded only twice, at 11.9 Ma (a dryopithecine with Pliopithecus) and at 11.6 Ma (a dryopithecine with Pliobates). The rare co-occurrence between great apes and small-bodied catarrhines might be attributable to sampling biases and/or to presumed diverging ecological preferences of these groups. In the future, more detailed analyses of the fauna recovered from the long and densely-sampled ACM sequence will hopefully throw new light on this long-standing, unresolved question