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排序方式: 共有368条查询结果,搜索用时 15 毫秒
1.
ABSTRACT The concept of digital game-based learning (DGBL) evolves rapidly together with technological enhancements of virtual reality (VR) and smart phones. However, the mental workload (MWL) that VR-training applications demand and motivational qualities originating from user experience (UX) should be identified in order to create effective and enjoyable training/learning challenges that fit with individual users’ capabilities. This study examined the effects of reality-based interaction (RBI) and VR on measures of student motivation and MWL, in a mental arithmetic game for secondary school pupils. In a randomised controlled trial with sixty school children, a mental arithmetic game was tested with three different interaction and two different presentation methods – VR RBI, VR head-mounted-display tapping and tablet flick-gesture. Results found a significant effect of RBI on MWL but no differences in enjoyment of training were found between VR-experience and tablet training-experience. In fact, adding the gaming-context to the mental arithmetic task created an enjoyable, motivating experience regardless of presentation or interaction-style. 相似文献
2.
Laura Francesca Pisani Gian Eugenio Tontini Carmine Gentile Beatrice Marinoni Isabella Teani Nicoletta Nandi Pasquale Creo Emanuele Asti Luigi Bonavina Maurizio Vecchi Luca Pastorelli 《International journal of molecular sciences》2021,22(11)
Interleukin (IL)-33 is a member of the interleukin (IL)-1 family of cytokines linked to the development of inflammatory conditions and cancer in the gastrointestinal tract. This study is designed to investigate whether IL-33 has a direct effect on human gastric epithelial cells (GES-1), the human gastric adenocarcinoma cell line (AGS), and the gastric carcinoma cell line (NCI-N87) by assessing its role in the regulation of cell proliferation, migration, cell cycle, and apoptosis. Cell cycle regulation was also determined in ex vivo gastric cancer samples obtained during endoscopy and surgical procedures. Cell lines and tissue samples underwent stimulation with rhIL-33. Proliferation was assessed by XTT and CFSE assays, migration by wound healing assay, and apoptosis by caspase 3/7 activity assay and annexin V assay. Cell cycle was analyzed by means of propidium iodine assay, and gene expression regulation was assessed by RT-PCR profiling. We found that IL-33 has an antiproliferative and proapoptotic effect on cancer cell lines, and it can stimulate proliferation and reduce apoptosis in normal epithelial cell lines. These effects were also confirmed by the analysis of cell cycle gene expression, which showed a reduced expression of pro-proliferative genes in cancer cells, particularly in genes involved in G0/G1 and G2/M checkpoints. These results were confirmed by gene expression analysis on bioptic and surgical specimens. The aforementioned results indicate that IL-33 may be involved in cell proliferation in an environment- and cell-type-dependent manner. 相似文献
3.
Maximina Romero María Isabel Martín Luisa Barbieri Fernanda Andreola Isabella Lancellotti Aurora López-Delgado 《Journal of the American Ceramic Society》2021,104(2):776-784
This work reports the results of an investigation aimed at the development of sintered glass-ceramic tiles by the sinter-crystallization of mixtures composed of aluminum slag and reclaimed packaging glass. The thermal behaviors of mixtures incorporating 50 and 60 wt% Al slag were established by differential thermal analysis (DTA). Green compacts were sintered in a temperature range of 800°C-1050°C and then soaked for 10-60 minutes. The mineralogical characterizations of the sintered materials were obtained by X-ray diffraction (XRD). The achieved results indicated that the sintering of aluminum slag and packaging glass reclaimed led to a glass-ceramic material composed mainly of needle-like crystals of wollastonite (CaSiO3). The bloating of samples during firing was evaluated according to a Cougny predictive diagram. After initial observations and according to bending strength characterizations, sintered tiles prepared from aluminum slag and glassy sand are appropriate for floor pavement and wall covering. 相似文献
4.
Mount Emily Gaultney Daniel Vrijsen Geert Adams Michael Baek So-Young Hudek Kai Isabella Louis Crain Stephen van Rynbach Andre Maunz Peter Kim Jungsang 《Quantum Information Processing》2016,15(12):5281-5298
Quantum Information Processing - Many of the challenges of scaling quantum computer hardware lie at the interface between the qubits and the classical control signals used to manipulate them.... 相似文献
5.
Rasmussen CD Jørgensen MB Carneiro IG Flyvholm MA Olesen K Søgaard K Holtermann A 《Ergonomics》2012,55(2):256-264
Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group. 相似文献
6.
In this paper we generalize the notion of compositional semantics to cope with transfinite reductions of a transition system. Standard denotational and predicate transformer semantics, even though compositional, provide inadequate models for some known program manipulation techniques. We are interested in the systematic design of extended compositional semantics, observing possible transfinite computations, i.e. computations that may occur after a given number of infinite loops. This generalization is necessary to deal with program manipulation techniques modifying the termination status of programs, such as program slicing. We include the transfinite generalization of semantics in the hierarchy developed in 1997 by P. Cousot, where semantics at different levels of abstraction are related with each other by abstract interpretation. We prove that a specular hierarchy of non-standard semantics modeling transfinite computations of programs can be specifiedin such a way that the standard hierarchy can be derived by abstract interpretation. We prove that non-standard transfinite denotational and predicate transformer semantics can be both systematically derived as solutions of simple abstract domain equations involving the basic operation of reduced power of abstract domains. This allows us to prove the optimality of these semantics, i.e. they are the most abstract semantics in the hierarchy which are compositional and observe respectively the terminating and initial states of transfinite computations, providing an adequate mathematical model for program manipulation. 相似文献
7.
Proteins as biomarkers of oxidative/nitrosative stress in diseases: the contribution of redox proteomics 总被引:8,自引:0,他引:8
Dalle-Donne I Scaloni A Giustarini D Cavarra E Tell G Lungarella G Colombo R Rossi R Milzani A 《Mass spectrometry reviews》2005,24(1):55-99
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) contribute to the pathogenesis and/or progression of several human diseases. Proteins are important molecular signposts of oxidative/nitrosative damage. However, it is generally unresolved whether the presence of oxidatively/nitrosatively modified proteins has a causal role or simply reflects secondary epiphenomena. Only direct identification and characterization of the modified protein(s) in a given pathophysiological condition can decipher the potential roles played by ROS/RNS-induced protein modifications. During the last few years, mass spectrometry (MS)-based technologies have contributed in a significant way to foster a better understanding of disease processes. The study of oxidative/nitrosative modifications, investigated by redox proteomics, is contributing to establish a relationship between pathological hallmarks of disease and protein structural and functional abnormalities. MS-based technologies promise a contribution in a new era of molecular medicine, especially in the discovery of diagnostic biomarkers of oxidative/nitrosative stress, enabling early detection of diseases. Indeed, identification and characterization of oxidatively/nitrosatively modified proteins in human diseases has just begun. 相似文献
8.
Margherita Passariello Veronica Ferrucci Emanuele Sasso Lorenzo Manna Rosa Rapuano Lembo Stefano Pascarella Giovanna Fusco Nicola Zambrano Massimo Zollo Claudia De Lorenzo 《International journal of molecular sciences》2022,23(10)
The dramatic experience with SARS-CoV-2 has alerted the scientific community to be ready to face new epidemics/pandemics caused by new variants. Among the therapies against the pandemic SARS-CoV-2 virus, monoclonal Antibodies (mAbs) targeting the Spike glycoprotein have represented good drugs to interfere in the Spike/ Angiotensin Converting Enzyme-2 (ACE-2) interaction, preventing virus cell entry and subsequent infection, especially in patients with a defective immune system. We obtained, by an innovative phage display selection strategy, specific binders recognizing different epitopes of Spike. The novel human antibodies specifically bind to Spike-Receptor Binding Domain (RBD) in a nanomolar range and interfere in the interaction of Spike with the ACE-2 receptor. We report here that one of these mAbs, named D3, shows neutralizing activity for virus infection in cell cultures by different SARS-CoV-2 variants and retains the ability to recognize the Omicron-derived recombinant RBD differently from the antibodies Casirivimab or Imdevimab. Since anti-Spike mAbs, used individually, might be unable to block the virus cell entry especially in the case of resistant variants, we investigated the possibility to combine D3 with the antibody in clinical use Sotrovimab, and we found that they recognize distinct epitopes and show additive inhibitory effects on the interaction of Omicron-RBD with ACE-2 receptor. Thus, we propose to exploit these mAbs in combinatorial treatments to enhance their potential for both diagnostic and therapeutic applications in the current and future pandemic waves of coronavirus. 相似文献
9.
Matteo Sibilano Valentina Tullio Gaspare Adorno Isabella Savini Valeria Gasperi Maria Valeria Catani 《International journal of molecular sciences》2022,23(10)
Among the surrounding cells influencing tumor biology, platelets are recognized as novel players as they release microvesicles (MVs) that, once delivered to cancer cells, modulate signaling pathways related to cell growth and dissemination. We have previously shown that physiological delivery of platelet MVs enriched in miR-126 exerted anti-tumor effects in different breast cancer (BC) cell lines. Here, we seek further insight by identifying AKT2 kinase as a novel miR-126-3p direct target, as assessed by bioinformatic analysis and validated by luciferase assay. Both ectopic expression and platelet MV-mediated delivery of miR-126-3p downregulated AKT2 expression, thus suppressing proliferating and invading properties, in either triple negative (BT549 cells) or less aggressive Luminal A (MCF-7 cells) BC subtypes. Accordingly, as shown by bioinformatic analysis, both high miR-126 and low AKT2 levels were associated with favorable long-term prognosis in BC patients. Our results, together with the literature data, indicate that miR-126-3p exerts suppressor activity by specifically targeting components of the PIK3/AKT signaling cascade. Therefore, management of platelet-derived MV production and selective delivery of miR-126-3p to tumor cells may represent a useful tool in multimodal therapeutic approaches in BC patients. 相似文献
10.
Rosa Luisa Potenza Pietro Lodeserto Isabella Orienti 《International journal of molecular sciences》2022,23(13)
Recently, several chemotherapeutic drugs have been repositioned in neurological diseases, based on common biological backgrounds and the inverse comorbidity between cancer and neurodegenerative diseases. Fenretinide (all-trans-N-(4-hydroxyphenyl) retinamide, 4-HPR) is a synthetic derivative of all-trans-retinoic acid initially proposed in anticancer therapy for its antitumor effects combined with limited toxicity. Subsequently, fenretinide has been proposed for other diseases, for which it was not intentionally designed for, due to its ability to influence different biological pathways, providing a broad spectrum of pharmacological effects. Here, we review the most relevant preclinical and clinical findings from fenretinide and discuss its therapeutic role towards cancer and neurological diseases, highlighting the hormetic behavior of this pleiotropic molecule. 相似文献