Search results for "Laboratory"
showing 10 items of 923 documents
Desarrollo de prácticas en el laboratorio químico en formato híbrido apoyadas en el trabajo en equipo y vídeos instructivos
2022
[EN] This work presents the adaptation of a course mainly based on practice sessions in the chemical laboratory into a blended learning format after the irruption of the COVID-19 pandemic. The study was conducted during the course Experimentation in Chemical Engineering II of the third academic year of the B.Sc. in Chemical Engineering of the Polytechnic University of València. The development of experimental courses under the context of the pandemic takes place under strict room occupancy and hygiene rules, although teamwork and interaction between students tends to be more important than in theory classes. To make feasible that students gain experience in the use of equipment and pilot pl…
Investigating face-to-face and virtual teamwork over time: When does early task conflict trigger relationship conflict?
2012
North Carolina State UniversityPast research has indicated that early task consict can trigger subsequent relationshipconsict during teamwork. The current study examines conditions that may exacerbateor attenuate this relationship. SpeciÞcally, this study examines the moderating role ofprocess consict and communication medium on the link between task consict andrelationship consict over time. A longitudinal laboratory experiment was carried outcomparing 22 face-to-face (FTF) groups, 22 videoconference (VC) groups, and 22synchronous computer mediated (i.e., OchatO) communication (CMC) groups workingon a complex team task over a period of 1 month. Results highlight the robust insuenceof early…
Zinc accumulation in the telencephalon of lizards.
1987
The zinc concentration in the brains of two species of lizard was determined by atomic-absorption spectrophotometry. The zinc concentration was found to be highest in the telencephalon of Lacerta galloti (21.1 micrograms/g fresh weight) and Podarcis hispanica (16.77 +/- 0.8 micrograms/g) while the mesencephalon and brain stem exhibited lower zinc concentrations, i.e., 7.0 micrograms/g in Lacerta galloti and 6.08 +/- 0.4 micrograms/g in Podarcis hispanica. This high telencephalic concentration of zinc is paralleled by intense and well-defined Timm reactivity used for demonstrating the presence of zinc-containing boutons at the light-microscope level. Volumetric-densitometric studies of these…
A mid-term estimate of 2018/2019 vaccine effectiveness to prevent laboratory confirmed A(H1N1)pdm09 and A(H3N2) influenza cases in Sicily (Italy)
2019
Abstract Influenza season started in Italy during the month of October 2018, approaching the epidemic peak in January 2019. This report aim to explore the mid-term virologic surveillance data of the 2018–2019 influenza season in Sicily and to estimate the effectiveness of seasonal influenza vaccine (VE) against A(H1N1)pdm09 and A(H3N2) influenza viruses. A test-negative design was used to evaluate influenza VE. In Sicily, almost all influenza infections were sustained by influenza type A viruses, of which 62.3% were A(H3N2) and 36.3% A(H1N1)pdm09. A reduction of laboratory confirmed influenza cases in Sicilian population immunized against influenza were observed. In particular, an overall s…
Abitare nel reale. Dalla crisi della periferia alla tessitura di nuove relazioni contestuali
2019
I progetti redatti per “Palermo Sud-Est” sono il risultato di un Laboratorio di Laurea strutturatosi attraverso incontri, seminari, comunicazioni specialistiche, esposizioni critiche, che – in una strategia condivisa – ha visto ogni studente elaborare il proprio lavoro nel confronto con gli altri attori del Laboratorio stesso. La ricerca sui “progetti urbani” è stata impostata di modo che ogni laureando fosse messo a conoscenza dei progetti svolti nello stesso ambito territoriale dai colleghi che l’avevano preceduto, così da poter operare in continuità e contribuire a formulare un ragionamento unitario, nel quale ogni progetto costituisse continuazione, verifica o anche variante dei precede…
Seeing reality through Einstein's eyes: a teaching proposal for special relativity
2021
The teaching of Special Relativity is still a critical issue not only for students but also for teachers. In this paper, we describe the trial of a learning unit on the Special Relativity topic based on Minkowski's approach through spacetime diagrams, following the results in pedagogical researches in this field. The main innovation of our project consists of a mechanical instrument: it allows to physically and mechanically represent Lorentz’s transformations by hands, exploring the effects of a change of the reference frame. Teachers and students can deal “by eye” with unusual phenomena as the loss of simultaneity, time dilation, length contraction, relativistic addition of velocities and …
L'interazione tra le esperienze formative del laboratorio, del tirocinio e delle lezioni
2012
Per favorire l’acquisizione della competenza professionale specifica del maestro è stata progettata e sperimentata una modalità formativa, rivolta agli studenti iscritti, nell’anno accademico 2008-2009, al primo ed al secondo anno del corso di laurea in Scienze della Formazione Primaria, in grado di integrare la teoria con la pratica. To favor the acquisition of specific professional competence of the teacher has been projected and experimented a training method, revolt to the enrolled students, in academic year 2008-2009, to the first one and the second year of the course of degree in Sciences of the Primary Formation, that integrates theory with practice.
Investigation of flashing phenomena in MSF chambers
2007
The MSF process has covered in the last years more than 50% of world production of desalinated water from the sea. Although this process has been used for several decades, the large energy requirements force to search for new and feasible ways to improve the overall thermal efficiency. Few studies have bee carried out in lab-scale, pilot and industrial MSF units, underlining the complexity of flashing phenomena and the importance of operating parameters settings for optimal performance. In the present work a study on fundamental phenomena occurring inside MSF chambers has been carried out, focusing on the dependence of flashing efficiency on operating parameters and the effects of flashing …
Measurement of the Convective Heat-Transfer Coefficient
2014
We propose an experiment for investigating how objects cool down toward the thermal equilibrium with its surrounding through convection. We describe the time dependence of the temperature difference of the cooling object and the environment with an exponential decay function. By measuring the thermal constant tau, we determine the convective heat-transfer coefficient, which is a characteristic constant of the convection system.
Assessment of the antioxidant and antibacterial activities of different olive processing wastewaters.
2017
Olive processing wastewaters (OPW), namely olive mill wastewater (OMW) and table-olive wastewaters (TOW) were evaluated for their antibacterial activity against five Gram-positive and two Gram-negative bacteria using the standard disc diffusion and thin layer chromatography (TLC)-bioautography assays. Disc diffusion screening and bioautography of OMW were compared to the phenolic extracts of table-olive brines. Positive activity against S. aureus was demonstrated. The optimization of chromatographic separation revealed that hexane/acetone in the ratio of 4:6 was the most effective for phenolic compounds separation. A HPLC-MS analysis was performed showing that only two compounds, hydroxytyr…