Holes and cracks in rigid foam films

The classical problem of foam film rupture dynamics has been investigated when surfaces exhibit very high rigidity due to the presence of specific surfactants. Two new features are reported. First a strong deviation to the well-known Taylor-Culick law is observed. Then, crack-like patterns can be visualized in the film; these patterns are shown to appear at a well defined deformation. The key role of surface active material on these features is quantitatively investigated, pointing the importance of surface elasticity to describe these fast dynamical processes, and thus providing an alternative tool to characterize surface elasticity in conditions extremely far from equilibrium. The origin of the cracks and their consequences on film rupturing dynamics are also discussed

Points of convergence between Judaism, Christianity and Islam in the quest for metaphilosophy of universalism

No Abstract

Optimizing scientific communication : the role of relative clauses as markers of complexity in English and German scientific writing between 1650 and 1900

The aim of this thesis is to show that both scientific English and German have become increasingly optimized for scientific communication from 1650 to 1900 by adapting the usage of relative clauses as markers of grammatical complexity. While the lexico-grammatical changes in terms of features and their frequency distribution in scientific writing during this period are well documented, in the present work we are interested in the underlying factors driving these changes and how they affect efficient scientific communication. As the scientific register emerges and evolves, it continuously adapts to the changing communicative needs posed by extra-linguistic pressures arising from the scientific community and its achievements. We assume that, over time, scientific language maintains communicative efficiency by balancing lexico-semantic expansion with a reduction in (lexico-)grammatical complexity on different linguistic levels. This is based on the idea that linguistic complexity affects processing difficulty and, in turn, communicative efficiency. To achieve optimization, complexity is adjusted on the level of lexico-grammar, which is related to expectation-based processing cost, and syntax, which is linked to working memory-based processing cost. We conduct five corpus-based studies comparing English and German scientific writing to general language. The first two investigate the development of relative clauses in terms of lexico-grammar, measuring the paradigmatic richness and syntagmatic predictability of relativizers as indicators of expectation-based processing cost. The results confirm that both levels undergo a reduction in complexity over time. The other three studies focus on the syntactic complexity of relative clauses, investigating syntactic intricacy, locality, and accessibility. Results show that intricacy and locality decrease, leading to lower grammatical complexity and thus mitigating memory-based processing cost. However, accessibility is not a factor of complexity reduction over time. Our studies reveal a register-specific diachronic complexity reduction in scientific language both in lexico-grammar and syntax. The cross-linguistic comparison shows that English is more advanced in its register-specific development while German lags behind due to a later establishment of the vernacular as a language of scientific communication.This work is supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project-ID 232722074 – SFB 110

Oral History Interview: Pauline Marie Clark Hairston

This interview is one of series conducted concerning the Oral History of Appalachia. Pauline Hairston was an African-American woman from West Virginia. She discusses: her experiences during World War II; her family and her husband\u27s family; rationing during World War II; moving to Delaware; working in a rayon company; working in an airplane factory; her husband\u27s service in the Navy; her brother\u27s service in the Army; a brief section on Franklin Roosevelt; raising her children; a black newspaper (the Afro American Digest); canning food; the end of the War; her education (including at Morris Harvey) and her husband\u27s education; her husband becoming a cabinet maker; her children; and her career in social work.https://mds.marshall.edu/oral_history/1530/thumbnail.jp

Models of site-based management and parent perception of student achievement: a national study

The investigation was conducted to document the prevalence of site-based management (SBM) as a form of decentralized governance in public schools. United States Government school census documents were used for the population from which 770 school districts were drawn for the sample. Superintendents from 187 school districts responded to Phase I of this investigation. Superintendents were asked if their school district used SBM, composition of site councils, selection processes of council membership, authority granted, content of decisions, and impact on student achievement;Phase II compared different models of SBM and their impact on student achievement. Three school districts were selected with different models of SBM: superintendent-initiated SBM, school board-initiated SBM, and state-mandated SBM. Comparisons were made between the school districts in the following areas: granted authority, content of decisions, time spent on issues, elements of functioning councils, and impact on student achievement. Comparisons were also made between parents and other members of the councils regarding the perceived impact of the different SBM models on student achievement;Statistical procedures used for this investigation were ANOVA, Scheffe, Bonferroni, and chi-tests;Fifty-four percent of the superintendents responding to this survey indicated their school district did use SBM. The superintendent-initiated SBM was the most frequent form of SBM. Authority granted to SBM councils was most frequently curriculum, followed by budget and personnel. The findings from the more detailed examination of SBM councils showed that state-mandated SBM councils spent more tune on curriculum and had a larger impact on student achievement than councils from superintendent-initiated or school board-initiated SBM;Seventy-seven percent of the superintendents of SBM governance reported SBM to have some to moderate impact on student achievement. Parents on councils from state-mandated SBM rated their councils to have a higher impact on student achievement than other forms of SBM. Parents on councils rated their councils to have a higher impact on student achievement than did other members of the councils

Neural and motor basis of inter-individual interactions

The goal of my Ph.D. work was to investigate the behavioral markers and the brain activities responsible for the emergence of sensorimotor communication. Sensorimotor communication can be defined as a form of communication consisting into flexible exchanges based on bodily signals, in order to increase the efficiency of the inter-individual coordination. For instance, a soccer player carving his movements to inform another player about his intention. This form of interaction is highly dependent of the motor system and the ability to produce appropriate movements but also of the ability of the partner to decode these cues. To tackle these facets of human social interaction, we approached the complexity of the problem by splitting my research activities into two separate lines of research. First, we pursued the examination of motor-based humans\u2019 capability to perceive and \u201cread\u201d other\u2019s behaviors in focusing on single-subject experiment. The discovery of mirror neurons in monkey premotor cortex in the early nineties (di Pellegrino et al. 1992) motivated a number of human studies on this topic (Rizzolatti and Craighero 2004). The critical finding was that some ventral premotor neurons are engaged during visual presentation of actions performed by conspecifics. More importantly, those neurons were shown to encode also the actual execution of similar actions (i.e. irrespective of who the acting individual is). This phenomenon has been highly investigated in humans by using cortical and cortico-spinal measures (for review see, fMRI: Molenberghs, Cunnington, and Mattingley 2012; TMS: Naish et al. 2014; EEG: Pineda 2008). During single pulse TMS (over the primary motor cortex), the amplitude of motor evoked potentials (MEPs) provides an index of corticospinal recruitment. During action observation the modulation of this index follow the expected changes during action execution (Fadiga et al. 1995). However, dozens of studies have been published on this topic and revealed important inconsistencies. For instance, MEPs has been shown to be dependent on observed low-level motor features (e.g. kinematic features or electromyography temporal coupling; Gangitano, Mottaghy, and Pascual-Leone 2001; Borroni et al. 2005; Cavallo et al. 2012) as well as high level movement properties (e.g. action goals; Cattaneo et al. 2009; Cattaneo et al. 2013). Furthermore, MEPs modulations do not seem to be related to the observed effectors (Borroni and Baldissera 2008; Finisguerra et al. 2015; Senna, Bolognini, and Maravita 2014), suggesting their independence from low-level movement features. These contradictions call for new paradigms. Our starting hypothesis here is that the organization and function of the mirror mechanism should follow that of the motor system during action execution. Hence, we derived three action observation protocols from classical motor control theories: 1) The first study was motivated by the fact that motor redundancy in action execution do not allow the presence of a one-to-one mapping between (single) muscle activation and action goals. Based on that, we showed that the effect of action observation (observation of an actor performing a power versus a precision grasp) are variable at the single muscle level (MEPs; motor evoked potentials) but robust when evaluating the kinematic of TMS-evoked movements. Considering that movements are based on the coordination of multiple muscle activations (muscular synergies), MEPs may represent a partial picture of the real corticospinal activation. Inversely, movement kinematics is both the final functional byproduct of muscles coordination and the sole visual feedback that can be extracted from action observation (i.e. muscle recruitment is not visible). We conclude that TMS-evoked kinematics may be more reliable in representing the state of the motor system during action observation. 2) In the second study, we exploited the inter-subject variability inherent to everyday whole-body human actions, to evaluate the link between individual motor signatures (or motor styles) and other\u2019s action perception. We showed no group-level effect but a robust correlation between the individual motor signature recorded during action execution and the subsequent modulations of corticospinal excitability during action observation. However, results were at odds with a strict version of the direct matching hypothesis that would suggest the opposite pattern. In fact, the more the actor\u2019s movement was similar to the observer\u2019s individual motor signature, the smaller was the MEPs amplitude, and vice versa. These results conform to the predictive coding hypothesis, suggesting that during AO, the motor system compares our own way of doing the action (individual motor signature) with the action displayed on the screen (actor\u2019s movement). 3) In the third study, we investigated the neural mechanisms underlying the visual perception of action mistakes. According to a strict version of the direct matching hypothesis, the observer should potentially reproduce the neural activation present during the actual execution of action errors (van Schie et al. 2004). Here, instead of observing an increase of cortical inhibition, we showed an early (120 ms) decrease of intracortical inhibition (short intracortical inhibition) when a mismatch was present between the observed action (erroneous) and the observer\u2019s expectation. As proposed by the predictive coding framework, the motor system may be involved in the generation of an error signal potentially relying on an early decrease of intracortical inhibition within the corticomotor system. The second line of research aimed at the investigation of how sensorimotor communication flows between agents engaged in a complementary action coordination task. In this regard, measures of interest where related to muscle activity and/or kinematics as the recording of TMS-related indexes would be too complicated in a joint-action scenario. 1) In the first study, we exploited the known phenomenon of Anticipatory Postural Adjustments (APAs). APAs refers to postural adjustments made in anticipation of a self- or externally-generated disturbance in order to cope for the predicted perturbation and stabilize the current posture. Here we examined how observing someone else lifting an object we hold can affect our own anticipatory postural adjustments of the arm. We showed that the visual information alone (joint action condition), in the absence of efference copy (present only when the subject is unloading by himself the object situated on his hand), were not sufficient to fully deploy the needed anticipatory muscular activations. Rather, action observation elicited a dampened APA response that is later augmented by the arrival of tactile congruent feedback. 2) In a second study, we recorded the kinematic of orchestra musicians (one conductor and two lines of violinists). A manipulation was added to perturb the normal flow of information conveyed by the visual channel. The first line of violinist where rotated 180\ub0, and thus faced the second line. Several techniques were used to extract inter-group (Granger Causality method) and intra-group synchronization (PCA for musicians and autoregression for conductors). The analyses were directed to two kinematic features, hand and head movements, which are central for functionally different action. The hand is essential for instrumental actions, whereas head movements encode ancillary expressive actions. During the perturbation, we observed a complete reshaping of the whole patterns of communication going in the direction of a distribution of the leadership between conductor and violinists, especially for what regards head movements. In fact, in the perturbed condition, the second line acts as an informational hub connecting the first line to the conductor they no longer can see. This study evidences different forms of communications (coordination versus synchronization) flowing via different channels (ancillary versus instrumental) with different time-scales

Anxiety, illness, beliefs and management of child type 1 diabetes

This portfolio thesis is comprised of three parts; a systematic literature review, an empirical study and a set of appendices

The role of the ion channel TRPV4 in the Late Asthmatic Response

In some patients, asthma is thought to be an atopic disease whereby exposure to allergens provokes symptoms. In fact, allergen inhalation can lead to a prolonged episode of airway narrowing named the late asthmatic response (LAR). Although it is a relevant clinical endpoint, the mechanisms driving it remain unclear. Evidence suggests that nerves could be involved, with allergen challenge resulting in the activation of airway sensory nerves within the vagus nerve and a subsequent reflex bronchospasm. This thesis investigated if the TRPV4 ion channel, a known activator of sensory nerves, could be a driver of the LAR. The ability of TRPV4 to stimulate airway sensory nerves was studied in Brown Norway rats. A TRPV4 agonist depolarised rat vagal nerves and this was inhibited by TRPV4 and P2X3-P2X2/3 antagonists, suggesting that TRPV4 signalling induces the release of ATP which stimulates P2X3-P2X2/3 receptors on the neurons. Therefore, further studies interrogated whether this TRPV4-P2X3 nerve axis could be driving the LAR. Accordingly, both TRPV4 and P2X3-P2X2/3 antagonists inhibited the LAR induced by ovalbumin (OVA) in Brown Norway rats, suggesting a role for the TRPV4-P2X3 axis in experimental LAR. Seeing these results, the mechanism leading to TRPV4 activation was investigated. PAR2 receptors, which are activated by proteases released upon allergen challenge, were considered as promising TRPV4 activators. Indeed, a PAR2 agonist depolarised rat vagal nerves and this was blocked by PAR2, TRPV4 and P2X3-P2X2/3 antagonists. However, two PAR2 antagonists did not reduce the LAR in the rat OVA model, suggesting that PAR2 receptors may not be involved in this model. Overall, these data suggest that the TRPV4-P2X3 axis could play a role in the LAR by activating airway sensory nerves. This thesis highlights that investigating receptors on airway sensory nerves could help to develop asthma therapies targeting alternative mechanisms than immune pathways.Open Acces