On the effect of measurementmodel misspecification in PLS Path Modeling: the reflective case

The specification of a measurement model as reflective or formative is the object of a lively debate. Part of the existing literature focuses on measurement model misspecification. This means that a true model is assumed and the impact on the path coefficients of using a wrong model is investigated. The majority of these studies is restricted to Structural Equation Modeling (SEM). Regarding PLS-Path Modeling (PLS-PM), a few authors have carried out simulation studies to investigate the robustness of the estimates, but their focus is the comparison with SEM. The present paper discusses the misspecification problem in the PLSPM context from a novel perspective. First, a real application on Alumni Satisfaction will be used to verify whether different assumptions for the measurements models influence the results. Second, the results of a Monte-Carlo simulation study, in the reflective case, will help to bring some clarity on a complex problem that has not been sufficiently studied yet

Immersive Movies: The Effect of Point of View on Narrative Engagement

Cinematic Virtual Reality (CVR) offers filmmakers a wide range of possibilities to explore new techniques regarding movie scripting, shooting and editing. Despite the many experiments performed so far with both live action and computer-generated movies, just a few studies focused on analyzing how these cinematic techniques actually affect the viewers’ experience. Like in traditional cinema, a key step for CVR screenwriters and directors is to choose from which perspective the viewers will see the scene, the so-called point of view (POV). The aim of this paper is to understand to what extent watching an immersive movie from a specific POV could impact the narrative engagement (NE), i.e., the viewers’ sensation of being immersed in the movie environment and being connected with its characters and story. Two POVs that are typically used in CVR, i.e., first-person perspective (1-PP) and external perspective (EP), are investigated through a user study in which both objective and subjective metrics were collected. The user study was carried out by leveraging two live action 360° short films with distinct scripts. The results suggest that the 1-PP experience could be more pleasant than the EP one in terms of overall NE and narrative presence, or even for all the NE dimensions if the potential of that POV is specifically exploited

Stress detection in computer users from keyboard and mouse dynamics

Detecting stress in computer users, while technically challenging, is of the utmost importance in the workplace, especially now that remote working scenarios are becoming ubiquitous. In this context, cost-effective, subject-independent systems are needed that can be embedded in consumer devices and classify users' stress in a reliable and unobtrusive fashion. Leveraging keyboard and mouse dynamics is particularly appealing in this context as it exploits readily available sensors. However, available studies are mostly performed in laboratory conditions, and there is a lack of on-field investigations in closer-to-real-world settings. In this study, keyboard and mouse data from 62 volunteers were experimentally collected in-the-wild using a purpose-built Web application, designed to induce stress by asking each subject to perform 8 computer tasks under different stressful conditions. The application of Multiple Instance Learning (MIL) to Random Forest (RF) classification allowed the devised system to successfully distinguish 3 stress-level classes from keyboard (76% accuracy) and mouse (63% accuracy) data. Classifiers were further evaluated via confusion matrix, precision, recall, and F1-score

An Optical System to Monitor the Displacement Field of Glass-fibre Posts Subjected to Thermal Loading

Endocanalar posts are necessary to build up and retain coronal restorations but they do not reinforce dental roots. It was observed that the dislodgement of post-retained restorations commonly occurs after several years of function and long-term retention may be influenced by various factors such as temperature changes. Temperature changes, in fact, produce micrometric deformations of post and surrounding tissues/materials that may generate high stress concentrations at the interface thus leading to failure. In this study we present an optical system based on the projection moiré technique that has been utilized to monitor the displacement field of endocanalar glass-fibre posts subjected to temperature changes. Measurements were performed on forty samples and the average displacement values registered at the apical and middle region were determined for six different temperature levels. A total of 480 displacement measurements was hence performed. The values of the standard deviation computed for each of the tested temperatures over the forty samples appear reasonably small which proves the robustness and the reliability of the proposed optical technique. The possible implications for the use of the system in the applicative context were discussed

Temporal and spatial variations of CO2 diffuse volcanic degassing on Cuicocha Caldera Lake – Ecuador

Cuicocha Caldera is the youngest eruptive center of Cotacachi-Cuicocha Volcanic Complex, located at the north of Ecuador. The caldera contains a lake of 3.95 km2 surface, and a maximum depth of 148 m. Cuicocha Lake is characterized by the presence of CO2 gaseous diffuse emissions, perceptible as bubbling zones. Since 2011, CO2 diffuse flux measurements have been performed in this lake using the accumulation chamber method. The data obtained from twenty surveys were processed by means of the Graphical Statistical Approach and the Sequential Gaussian Simulation. The results reveal that Cuicocha lake has released a total estimated amount of ~400 kt of CO2 in the period between March 2011 and May 2019, with an average rate of 135 t/day. Furthermore, the spatial and temporal analysis of the data made possible the understanding of the processes occurring in the lake: 1) Lake stratification caused by the seasons seem to favor CO2 accumulation in the hipolimnion and its posterior releasing. Minimum total flux values of ~50 t/day have been estimated during “warm” stratified periods and maximum flux values of ~170 t/day have been recorded during “cold” overturn periods. Additionally, at least two anomalous degassing episodes were identified in 2012–2013, seemingly associated to changes in the volcanic activity also detected through seismicity. 2) Cuicocha CO2 degassing seems to be controlled by the existence of diffuse degassing structures at the lake bottom, which correspond to high permeability zones resulting from the intersection between ~NE-SW and ~WNW-ESE oriented structures. We propose a conceptual model to explain the systematic apparition of CO2 anomalies on specific areas of the lake surface.Fil: Sierra Vaca, Daniel Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina. Instituto Geofísico de la Escuela Politécnica Nacional; EcuadorFil: Hidalgo, Silvana. Instituto Geofísico de la Escuela Politécnica Nacional; EcuadorFil: Almeida, Marco. Instituto Geofísico de la Escuela Politécnica Nacional; EcuadorFil: Vigide, Nicolás Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Lamberti, María Clara Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Proaño, Antonio. Instituto Geofísico de la Escuela Politécnica Nacional; EcuadorFil: Narváez, Diego F.. Instituto Geofísico de la Escuela Politécnica Nacional; Ecuado

Apoptosis Therapy in Cancer: The First Single-molecule Co-activating p53 and the Translocator Protein in Glioblastoma

In the complex scenario of cancer, treatment with compounds targeting multiple cell pathways has been emerging. In Glioblastoma Multiforme (GBM), p53 and Translocator Protein (TSPO), both acting as apoptosis inducers, represent two attractive intracellular targets. On this basis, novel indolylglyoxylyldipeptides, rationally designed to activate TSPO and p53, were synthesized and biologically characterized. The new compounds were able to bind TSPO and to reactivate p53 functionality, through the dissociation from its physiological inhibitor, murine double minute 2 (MDM2). In GBM cells, the new molecules caused Δψm dissipation and inhibition of cell viability. These effects resulted significantly higher with respect to those elicited by the single target reference standards applied alone, and coherent with the synergism resulting from the simultaneous activation of TSPO and p53. Taken together, these results suggest that TSPO/MDM2 dual-target ligands could represent a new attractive multi-modal opportunity for anti-cancer strategy in GBM

Heuristic optimization of RC bridge piers with rectangular hollow sections

This paper deals with the economic optimization of reinforced concrete (RC) bridge piers with hollow rectangular sections and describes the efficiency of three heuristic algorithms: two new variants of the ant colony optimization (ACO) algorithm, the genetic algorithm (GA) and the threshold acceptance (TA) algorithm. The GA and TA are used for comparison with the new ACO algorithms. The total number of variables is 95. All variables are discrete in this analysis. The calibration of the new ACO algorithm recommended a 250-member ant population and 100 stages. The best solution costs 69,467 euros, which means savings of about 33% as compared to experience-based design. Finally, results indicate that the new ACO algorithms are potentially useful for optimizing the costs of real RC structures.This study was funded by the Spanish Ministry of Education (Research Project BIA2006-01444). The authors are grateful for the thorough revision of the manuscript by Dr. Debra Westall.Martínez Martín, FJ.; González Vidosa, F.; Hospitaler Pérez, A.; Yepes Piqueras, V. (2010). Heuristic optimization of RC bridge piers with rectangular hollow sections. Computers and Structures. 88:375-386. https://doi.org/10.1016/j.compstruc.2009.11.009S3753868