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111.
Andrea Bianconi Gelsomina Aruta Francesca Rizzo Luca Francesco Salvati Pietro Zeppa Diego Garbossa Fabio Cofano 《International journal of molecular sciences》2022,23(8)
Despite the multidisciplinary management in the treatment of glioblastomas, the average survival of GBM patients is still 15 months. In recent years, molecular biomarkers have gained more and more importance both in the diagnosis and therapy of glial tumors. At the same time, it has become clear that non neoplastic cells, which constitute about 30% of glioma mass, dramatically influence tumor growth, spread, and recurrence. This is the main reason why, in recent years, scientific research has been focused on understanding the function and the composition of tumor microenvironment and its role in gliomagenesis and recurrence. The aim of this review is to summarize the most recent discovery about resident microglia, tumor-associated macrophages, lymphocytes, and the role of extracellular vesicles and their bijective interaction with glioma cells. Moreover, we reported the most recent updates about new therapeutic strategies targeting immune system receptors and soluble factors. Understanding how glioma cells interact with non-neoplastic cells in tumor microenvironment is an essential step to comprehend mechanisms at the base of disease progression and to find new therapeutic strategies for GBM patients. However, no significant results have yet been obtained in studies targeting single molecules/pathways; considering the complex microenvironment, it is likely that only by using multiple therapeutic agents acting on multiple molecular targets can significant results be achieved. 相似文献
112.
Jos C. Meurer Fabio A. P. Rizzante Rafael M. Maenossono Fabiana M. G. Frana Juliana F. S. Bombonatti Srgio K. Ishikiriama 《Microscopy research and technique》2020,83(3):304-309
The quality of the micromechanical retention between the enamel prisms exposed through acid etching and adhesive system can be influenced by the relationship between the angle of the exposed enamel prisms and the external surface/restorative material. Therefore, the aim of the present study was to determine the influence of the enamel cavosurface beveling in different cavity sizes on the angle relation between enamel prisms and the restorative material. For this research, 30 human permanent molars were used and divided into three groups according the isthmus aperture of class I cavities (1/4, 1/3, and 1/2 of the intercuspal distance). Cavosurface angle beveling was performed in each tooth buccal or palatal/lingual side, and a resin composite restoration was placed. Each restored tooth was sectioned in buccal/palatal direction followed by analysis in scanning electron microscope. Means of the angles observed between enamel prisms and the restorative material were registered and statistically analyzed by Kruskal‐Wallis test. Results showed higher mean angle values for beveled groups when comparing with the values observed in the unbeveled margins (p < .05) regardless of the isthmus aperture, being 1/4 (beveled = 48.36°; unbeveled = 20.71°), 1/3 (beveled = 39.75°; unbeveled = 29.15°), and 1/2 (beveled = 37.02°; unbeveled = 26.34°). It was also observed that in some unbeveled cavities, there were the presence of laterally exposed enamel prisms (0°), mainly in more conservative cavities. It was concluded that the presence of higher angles values occurred in the samples with beveled margins, without presence of laterally exposed enamel prisms. 相似文献
113.
Fabio R.J. Vieira José F. de Rezende Valmir C. Barbosa Serge Fdida 《Computer Networks》2012,56(5):1584-1598
We consider wireless mesh networks and the problem of scheduling the links of a given set of routes under the assumption of a heavy-traffic pattern. We assume some TDMA protocol provides a background of synchronized time slots and seek to schedule the routes’ links to maximize the number of packets that get delivered to their destinations per time slot. Our approach is to construct an undirected graph G and to heuristically obtain node multicolorings for G that can be turned into efficient link schedules. In G each node represents a link to be scheduled and the edges are set up to represent every possible interference for any given set of interference assumptions. We present two multicoloring-based heuristics and study their performance through extensive simulations. One of the two heuristics is based on relaxing the notion of a node multicoloring by dynamically exploiting the availability of communication opportunities that would otherwise be wasted. We have found that, as a consequence, its performance is significantly superior to the other’s. 相似文献
114.
Teaching HCI in an undergraduate course for computer scientists is often a challenging experience, because the skills that characterize HCI are different from scientific and computational thinking that are the focus of most subjects of the curriculum. Often HCI teaching is organized as a set of lectures that are useful to learn concepts, but don’t increase the design skills of the students. This work reports the results of an educational experience where both learners and teachers were actively involved in a process of knowledge construction and design. This process usually happens in other domains, such as architecture or industrial design, but is not part of most computer science curricula. We chose as project a challenging theme: the design of eco-feedback interfaces that inform people about the consequences of their actions for the environment and help to take decisions for lowering energy consumption. Eco-feedback interfaces are also representative of the gap between the products available on the market and the results of scientific studies, evidenced also by a recent workshop about HCI education. The workshop evidenced a number of pitfalls in HCI education that in our educational experience we tried to overcome with appropriate methodologies. An additional challenging task was the attempt to organize all the design activities taking advantage of a platform for remote learning, stressing its limits. The paper will discuss all these issues, evidencing where the applied methodologies gave good results and where they need further improvements, with the final goal of giving useful advices for HCI educational experiences to come. 相似文献
115.
This paper contributes to fill the gap between the literature on the determinants of firm survival and the empirical works on the industry life cycle (ILC). Using a representative sample of Spanish firms with 10 or more employees over the period 1993–2009, the role played by firm age and productivity in firm survival is empirically analysed across three stages of the life cycle of forty-seven 3-digit manufacturing sectors. In the ‘early’ stage of the ILC, firm age is negatively correlated with hazard rates while firm productivity is not. Firm productivity is associated with lower hazard in the ‘mature’ stage of the ILC, when competition is primarily efficiency-driven, while firm age does not play a significant role for firm survival. In the ‘intermediate’ stage, both age and productivity play a role in reducing firms’ hazard rates. 相似文献
116.
We present an electrostrictive polymer bimorph controllable with low voltage through an integrated CMOS OFET control system. We have actuated the device by applying voltages up to 400 V to the control system, and can actuate the control with 60 V switching. The electrostrictor material was used both as the substrate for the transistors and as the dielectric layer for the control circuitry. This allows for a reduction in the number of layers in the structure, minimizing the clamping effect that would compromise the strain capabilities of the device. We have characterized the macroscopic displacement of the structure through a radius of curvature measurement, ranging from 11.4 mm to 7.5 mm depending on the supply voltage provided. The architecture proposed can be scaled to larger system with higher supply voltages. 相似文献
117.
118.
Thirty commercially available Italian carbonic macerated young red wines, have been analysed by HPLC–DAD–MS with the aim to characterise their pigment composition and find possible correlations with the colour features evaluated by means of spectrophotometric measurements. The composition in anthocyanin monoglucosides, acetates, p-coumarates as well as that in pyranoanthocyanins and direct and ethyl-bridged adducts with flavanols, was studied. Because of the peculiar maceration process, carbonic macerated wines demonstrated to be qualitatively rich in pyranoanthocyanins and pigment adducts. A number of ethyl-bridged anthocyanin isomers was found, together with significant contents of vitisin A and vitisin B (up to 15.5 mg/L as a sum). Malvidin-3-glc-4-vinylphenol was the main pyranoanthocyanin-vinylphenol adduct (up to 1.10 mg/L). The colour features of the wines were broadly distributed as a consequence of the percentage of carbonic macerated wine present in the marketed product. The statistical treatment of the entire data set revealed that pyranoanthocyanins are positively correlated with colour density (while no correlation was found for monoglucosides) and that direct adducts and/or ethyl-bridged compounds can play a role for what concerns the hue of carbonic macerated wines. 相似文献
119.
Andr Neto Filippo Sartori Fabio Piccolo Antonio Barbalace Riccardo Vitelli Horcio Fernandes JET-EFDA 《Fusion Engineering and Design》2009,84(7-11):1408-1411
A new framework for the development and execution of real-time codes is currently being developed and commissioned at JET. The foundations of the system are Linux, the Real Time Application Interface (RTAI) and a wise exploitation of the new i386 multi-core processors technology.The driving motivation was the need to find a real-time operating system for the i386 platform able to satisfy JET Vertical Stabilisation Enhancement project requirements: 50 μs cycle time. Even if the initial choice was the VxWorks operating system, it was decided to explore an open source alternative, mostly because of the costs involved in the commercial product.The work started with the definition of a precise set of requirements and milestones to achieve: Linux distribution and kernel versions to be used for the real-time operating system; complete characterization of the Linux/RTAI real-time capabilities; exploitation of the multi-core technology; implementation of all the required and missing features; commissioning of the system.Latency and jitter measurements were compared for Linux and RTAI in both user and kernel-space. The best results were attained using the RTAI kernel solution where the time to reschedule a real-time task after an external interrupt is of 2.35 ± 0.35 μs. In order to run the real-time codes in the kernel-space, a solution to provide user-space functionalities to the kernel modules had to be designed. This novel work provided the most common functions from the standard C library and transparent interaction with files and sockets to the kernel real-time modules. Kernel C++ support was also tested, further developed and integrated in the framework.The work has produced very convincing results so far: complete isolation of the processors assigned to real-time from the Linux non real-time activities, high level of stability over several days of benchmarking operations and values well below 3 μs for task rescheduling after external interrupt. From being the alternative option, RTAI has been finally chosen as the platform for the project. A first stable version of the framework has been integrated on the JET system and is already being commissioned. It will be soon be used on the Vertical Stabilisation Enhancement for the Plasma Control Upgrade (PCU) project at JET. 相似文献
120.