958 research outputs found
Digital Competence in K-12 : theoretical models, assessment tools and empirical research
Over the last years the theme of the digital competence in its different aspects has been object of a growing interest. In a number of official documents and communications, international bodies underlined the significance of this competence for lifelong learning and to participate in the so-called 'information society'. Within this context, education research has the duty to provide realistic conceptual models coherent with the school's objectives and which can be put into practice within the school curriculum. In the present paper, we shall introduce a theoretical model, education oriented, to represent this competence and a set of tools to assess it in the school context, i.e., the Instant DCA (iDCA) and the Situated DCA. Then we shall focus on iDCA and on the results of the testing carried out over the last two years in the Italian secondary school.Durante los últimos años el tema de la competencia digital en sus diferentes aspectos ha sido objeto de un creciente interés. Los organismos internacionales han destacado a importancia de esta competencia para el aprendizaje permanente y la inclusión en la sociedad de la información en una serie de documentos oficiales. Dentro de este contexto, la investigación educativa tiene el deber de proporcionar modelos conceptuales coherentes con los objetivos de la escuela y que se puedan poner en práctica dentro del currÃculum escolar. En el presente trabajo, introducimos un modelo teórico, orientado a la educación, para desarrollar esta competencia y un conjunto de herramientas para evaluarla en el contexto escolar
Palladium(II)-Catalyzed Cross-Dehydrogenative Coupling (CDC) of N-Phthaloyl Dehydroalanine Esters with Simple Arenes: Stereoselective Synthesis of Z-Dehydrophenylalanine Derivatives
Pd(II)-catalyzed cross-dehydrogenative coupling (CDC) of methyl N-phthaloyl dehydroalanine esters with simple aromatic hydrocarbons is reported. The reaction, which involves the cleavage of two sp(2) C-H bonds followed by C-C bond formation, stereoselectively generates highly valuable Z-dehydrophenylalanine skeletons in a practical, versatile, and atom economical manner. In addition, a perfluorinated product was expediently converted into important nonproteinogenic amino acid building blocks through copper-catalyzed conjugate additions of boron, silicon, and hydride moieties
La competenza digitale nella scuola. Modelli, strumenti, ricerche
Nel corso degli ultimi anni il tema della competenza digitale, nei suoi diversi aspetti, è stato oggetto di attenzione crescente. In vari documenti e comunicazioni, gli organismi internazionalihanno sottolineato la rilevanza di questa competenza per il lifelong learning e per la piena partecipazione alla cosiddetta‘società dell’informazione’. In questo contesto, la ricerca educativaha il compito di mettere a punto modelli concettuali realistici coerenti con gli obiettivi della scuola e facilmente integrabilinel curriculum scolastico. In questo lavoro, presenteremo un modello teorico per la rappresentazione di questa competenza, sensibile alle istanze educative, ed illustreremo una serie distrumenti per valutarla in ambito scolastico, ossia l’Instant DCA (iDCA) e il Situated DCA. Successivamente ci soffermeremo sull’iDCA e sui risultati di una sperimentazione condotta negli ultimidue anni nella scuola secondaria superiore
Pronuclear morphology evaluation for fresh in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles: A systematic review
The current systematic review was aimed to assess the effectiveness of the zygote morphology evaluation in fresh in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles. All available studies reporting on zygote morphology and clinical and/or biological outcomes were analyzed. Forty studies were included in the final analysis. Fourteen different zygote scoring systems were employed. Zygote morphology correlated significantly with embryo quality and cleavage, blastocyst stage, embryonic chromosome status, in a high proportion of the studies which assessed the specific outcome [15/25 (60%), 15/20 (75%), 7/8 (87.5%), 6/6 (100%), respectively]. On the other hand, only a reduced proportion of papers showed a statistically significant relationship between implantation, pregnancy and delivery/live-birth rates and zygote morphology score [12/23 (52.2%), 12/25 (48%), 1/4 (25%), respectively]. In conclusion, our findings demonstrate the lack of conclusive data on the clinical efficacy of the zygote morphology evaluation in fresh IVF/ICSI cycles, even if biological results showing a good relationship with embryo viability suggest a role in cycles in which the transfer/freezing is performed at day 1. \ua9 2013Nicoli et al.; licensee BioMed Central Ltd
The psychological consequences of Sudden Infant Death Syndrome (SIDS) for the family system: A systematic review
Multibody Computer Model of the Entire Equine Forelimb Simulates Forces Causing Catastrophic Fractures of the Carpus during a Traditional Race
Simple Summary Palios are traditional horseraces held in the main square of few Italian cities. Due to peculiar features of such circuits, adapted to the square architecture and thus characterized by tight curves and unconventional footing surface, horses involved are at particular risk of accidents. Prevention of catastrophic musculoskeletal injuries is a significant issue and matter of debate during these events. In particular, the negotiation of the curves in the city circuits is a significative concern. An experiment was set up to build a model of entire forelimb at the point of failure in the context of a turn comparable to that in a Palio circuit. The model was informed by live data and the output compared to post-mortem findings obtained from a horse that sustained a catastrophic fracture of the carpus during this competition. The objective of this study is to determine the magnitude and distribution of internal forces generated across the carpus under which the catastrophic injury has occurred and describe related post-mortem findings. A catastrophic fracture of the radial carpal bone experienced by a racehorse during a Palio race was analyzed. Computational modelling of the carpal joint at the point of failure informed by live data was generated using a multibody code for dynamics simulation. The circuit design in a turn, the speed of the animal and the surface characteristics were considered in the model. A macroscopic examination of the cartilage, micro-CT and histology were performed on the radio-carpal joint of the limb that sustained the fracture. The model predicted the points of contact forces generated at the level of the radio-carpal joint where the fracture occurred. Articular surfaces of the distal radius, together with the proximal articular surface of small carpal bones, exhibited diffuse wear lines, erosions of the articular cartilage and subchondral bone exposure. Even though the data in this study originated from a single fracture and further work will be required to validate this approach, this study highlights the potential correlation between elevated impact forces generated at the level of contact surfaces of the carpal joint during a turn and cartilage breakdown in the absence of pre-existing pathology. Computer modelling resulted in a useful tool to inversely calculate internal forces generated during specific conditions that cannot be reproduced in-vivo because of ethical concerns
Collaborative Practices and Multidisciplinary Research : The Dialogue Between Entrepreneurship, Management, and Data Science
Author's accepted version (post-print).Available from 06/06/2020.acceptedVersio
Ionized jet deposition of silver nanostructured coatings: Assessment of chemico-physical and biological behavior for application in orthopedics
Infection is one of the main issues connected to implantation of biomedical devices and represents a very difficult issue to tackle, for clinicians and for patients. This study aimed at tackling infection through antibacterial nanostructured silver coatings manufactured by Ionized Jet Deposition (IJD) for application as new and advanced coating systems for medical devices. Films composition and morphology depending on deposition parameters were investigated and their performances evaluated by correlating these properties with the antibacterial and antibiofilm efficacy of the coatings, against Escherichia coli and Staphylococcus aureus strains and with their cytotoxicity towards human cell line fibroblasts. The biocompatibility of the coatings, the nanotoxicity, and the safety of the proposed approach were evaluated, for the first time, in vitro and in vivo by rat subcutaneous implant models. Different deposition times, corresponding to different thicknesses, were selected and compared. All silver coatings exhibited a highly homogeneous surface composed of nanosized spherical aggregates. All coatings having a thickness of 50 nm and above showed high antibacterial efficacy, while none of the tested options caused cytotoxicity when tested in vitro. Indeed, silver films impacted on bacterial strains viability and capability to adhere to the substrate, in a thickness-dependent manner. The nanostructure obtained by IJD permitted to mitigate the toxicity of silver, conferring strong antibacterial and anti-adhesive features, without affecting the coatings biocompatibility. At the explant, the coatings were still present although they showed signs of progressive dissolution, compatible with the release of silver, but no cracking, delamination or in vivo toxicity was observed
Establishment of an in Vitro Human Blood-Brain Barrier Model Derived from Induced Pluripotent Stem Cells and Comparison to a Porcine Cell-Based System
The blood-brain barrier (BBB) is responsible for the homeostasis between the cerebral vasculature and the brain and it has a key role in regulating the influx and efflux of substances, in healthy and diseased states. Stem cell technology offers the opportunity to use human brain-specific cells to establish in vitro BBB models. Here, we describe the establishment of a human BBB model in a two-dimensional monolayer culture, derived from human induced pluripotent stem cells (hiPSCs). This model was characterized by a transendothelial electrical resistance (TEER) higher than 2000 Ω∙cm2 and associated with negligible paracellular transport. The hiPSC-derived BBB model maintained the functionality of major endothelial transporter proteins and receptors. Some proprietary molecules from our central nervous system (CNS) programs were evaluated revealing comparable permeability in the human model and in the model from primary porcine brain endothelial cells (PBECs)
I.S.Mu.L.T. Achilles Tendon Ruptures Guidelines
This work provides easily accessible guidelines for the diagnosis, treatment and rehabilitation of Achilles tendon ruptures. These guidelines could be considered as recommendations for good clinical practice developed through a process of systematic review of the literature and expert opinion, to improve the quality of care for the individual patient and rationalize the use of resources. This work is divided into two sessions: 1) questions about hot topics; 2) answers to the questions following Evidence Based Medicine principles. Despite the frequency of the pathology andthe high level of satisfaction achieved in treatment of Achilles tendon ruptures, a global consensus is lacking. In fact, there is not a uniform treatment and rehabilitation protocol used for Achilles tendon ruptures
- …