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Universal Access in the Information Society - Technology and videogames have been proven as motivating tools for working attention and complex communication skills, especially in children with...  相似文献   
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Ultraviolet B (UVB) radiation acts as a strong apoptotic trigger in many cell types, in tumor and normal cells. Several studies have demonstrated that UVB-induced cell death occurs through the generation of reactive oxygen species. The consequent oxidative stress includes the impairment of cellular antioxidants, the induction of DNA damage and the occurrence of apoptosis. In this review, we investigated UVB apoptotic action in various cell models by using ultrastructural, molecular and cytofluorimetric techniques. Myeloid leukemia HL-60, T-lymphoblastoid Molt-4 and myelomonocytic U937 human cells, generally affected by apoptotic stimuli, were studied. Human chondrocytes and C2C12 skeletal muscle cells, known to be more resistant to damage, were also considered. All of them, when exposed to UVB radiation, revealed a number of characteristic apoptotic markers. Membrane blebbing, cytoplasm shrinkage and chromatin condensation were detected by means of electron microscopy. DNA cleavage, investigated by using agarose gel electrophoresis and TUNEL reaction, was observed in suspended cells. Differently, in chondrocytes and in skeletal muscle cells, oligonucleosomic DNA fragmentation did not appear, even if a certain TUNEL positivity was detected. These findings demonstrate that UVB radiation appears to be an ideal tool to study the apoptotic behavior.  相似文献   
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Laser action with low threshold average pump power density (~50 W - cm-2 ) at room temperature is reported for a crack-free planar vertical cavity surface emitting laser (VCSEL) structure based on a bottom lattice-matched AllnN/GaN distributed Bragg reflector (DBR) and a top dielectric DBR. The cavity region, formed by n- and p-type GaN layers surrounding only three InGaN/GaN quantum wells, corresponds to a typical active region suitable for an electrically driven VCSEL. In addition to low threshold, a spontaneous emission coupling factor beta ~ 2 x 10-10 is derived for this ready-to-be-processed laser structure.  相似文献   
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Oxidative stress increase induces cellular damage and apoptosis activation, a mechanism believed to represent a final common pathway correlated to sarcopenia and many skeletal muscle disorders. The goal of this study is to evaluate if melatonin, a ROS scavenger molecule, is able to counteract or modulate myotube death. Here, differentiated C2C12 skeletal muscle cells have been treated with melatonin before chemicals known to induce apoptotic death and oxidative stress, and its effect has been investigated by means of morpho‐functional analyses. Ultrastructural observations show melatonin protection against triggers by the reducing of membrane blebbing, chromatin condensation, myonuclei loss and in situ DNA cleavage. Moreover, melatonin is able to prevent mitochondrial dysfunctions which occur in myotubes exposed to the trigger alone. These findings demonstrate melatonin ability in preventing apoptotic cell death in skeletal muscle fibers in vitro, suggesting for this molecule a potential therapeutic role in the treatment of various muscle disorders.  相似文献   
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A cytokine storm, autoimmune features and dysfunctions of myeloid cells significantly contribute to severe coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Genetic background of the host seems to be partly responsible for severe phenotype and genes related to innate immune response seem critical host determinants. The C9orf72 gene has a role in vesicular trafficking, autophagy regulation and lysosome functions, is highly expressed in myeloid cells and is involved in immune functions, regulating the lysosomal degradation of mediators of innate immunity. A large non-coding hexanucleotide repeat expansion (HRE) in this gene is the main genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), both characterized by neuroinflammation and high systemic levels of proinflammatory cytokines, while HREs of intermediate length, although rare, are more frequent in autoimmune disorders. C9orf72 full mutation results in haploinsufficiency and intermediate HREs seem to modulate gene expression as well and impair autophagy. Herein, we sought to explore whether intermediate HREs in C9orf72 may be a risk factor for severe COVID-19. Although we found intermediate HREs in only a small portion of 240 patients with severe COVID-19 pneumonia, the magnitude of risk for requiring non-invasive or mechanical ventilation conferred by harboring intermediate repeats >10 units in at least one C9orf72 allele was more than twice respect to having shorter expansions, when adjusted for age (odds ratio (OR) 2.36; 95% confidence interval (CI) 1.04–5.37, p = 0.040). The association between intermediate repeats >10 units and more severe clinical outcome (p = 0.025) was also validated in an independent cohort of 201 SARS-CoV-2 infected patients. These data suggest that C9orf72 HREs >10 units may influence the pathogenic process driving more severe COVID-19 phenotypes.  相似文献   
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Bucci  G. Neri  G. Baldassarri  F. 《Computer》1981,14(10):81-90
How can the performance of ystems containing obsolete technology be improved? Emulation and microprogramming provide cost-effective answers for real-time applications in a process control environment.  相似文献   
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The tangible interaction approach has in recent years become a promising alternative to multitouch tabletops for very young children. Children learning with tangible user interfaces can benefit from the same pedagogical values as learning with materials in physical play. The NIKVision tabletop and games have been designed to provide leisure and fun while reinforcing physical manipulation and co-located gaming for young children (3- to 6-year-olds). Interaction is provided in NIKVision by the handling of conventional toys and computer augmentation on a table surface. First of all, the paper sets out the results of a summative evaluation carried out in nurseries and schools summarising the performance of the tabletop in terms of usability, user experience and physical and co-located gaming. Secondly, the paper presents an evaluation carried out in a special education school with children with cognitive disabilities, in an attempt to widen the range of possible beneficiaries of tangible interfaces. The challenge in this case is to ensure children’s comprehension of the game and to adequately combine feedback on the application with teacher interventions. In fact, the initial results reinforce the idea of not trying to substitute but rather to assist teachers and emphasise the possibilities offered by the tabletop as a tool to promote student autonomy.  相似文献   
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Universal Access in the Information Society - In this work, we have studied the potentialities of tangible tabletops when applied to the therapy of children with developmental problems. The...  相似文献   
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