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71.
Transport of holes in thin films of a low-bandgap alternating polyfluorene copolymer, APFO-Green5, was investigated by means of admittance spectroscopy as a function of field and temperature. The values of hole mobility were evaluated from the position of the maxima in the plots of the negative differential susceptance as a function of frequency. Hole mobility was found to be strongly field- and temperature-dependent. The charge transport parameters were extracted by analyzing the mobility data by the uncorrelated and the correlated Gaussian Disorder Models.  相似文献   
72.
It is well known that software maintenance and evolution are expensive activities, both in terms of invested time and money. Reverse engineering activities support the obtainment of abstractions and views from a target system that should help the engineers to maintain, evolve and eventually re-engineer it. Two important tasks pursued by reverse engineering are design pattern detection and software architecture reconstruction, whose main objectives are the identification of the design patterns that have been used in the implementation of a system as well as the generation of views placed at different levels of abstractions, which let the practitioners focus on the overall architecture of the system without worrying about the programming details it has been implemented with.In this context we propose an Eclipse plug-in called MARPLE (Metrics and Architecture Reconstruction Plug-in for Eclipse), which supports both the detection of design patterns and software architecture reconstruction activities through the use of basic elements and metrics that are mechanically extracted from the source code. The development of this platform is mainly based on the exploitation of the Eclipse framework and plug-ins as well as of different Java libraries for data access and graph management and visualization. In this paper we focus our attention on the design pattern detection process.  相似文献   
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74.
Francesca Galeazzi is an architectural engineer who leads the sustainability team at Arup Associates in Shanghai. Here she looks back with hindsight from 2050, reflecting on how rapid urbanisation in China, which started in the 1990s, played out over the next half-century. She describes how the initial highly centralised, mass urbanisation programmes gave way to a more local and community-based, participatory approach to decision-making and planning, foreshadowed by some key legislation around land ownership and design for community-based planning models in the early 2010s.  相似文献   
75.
The “Virtual Design Studio (VDS)” is a software platform currently under development in support of an integrated, coordinated and optimized design of buildings and their energy and environmental systems. It is intended to assist collaborating architects, engineers and project management team members throughout from the early phases to the detailed building design development. The platform helps to facilitate the workflow and the processing of information in combination with appropriate, task-based performance simulation tools as further analyzed in Part 2 of this study (DOI: 10.1007/s12273-013-0111-1). The present paper summarizes how VDS relates to the building design process and its typical project stages, performance-based design considerations and respective performance optimization strategies. It outlines the methodology and scope for the organization, implementation and respective requirements for the VDS platform development based on the interdisciplinary design needs. Part 2 will present the methodology for the systems integration and software implementation of VDS.  相似文献   
76.
This article explores the relationships between changes in the conception of urban peripheries and changes in urban renewal policies, mainly focusing on policy debates and theoretical discourses developed within Italy. The aim is to test the usefulness of a non‐conventional approach to urban peripheries, both from a theoretical and practical point of view. According to this approach, urban peripheries can be thought of as plural and complex places, which are considered to be a fundamental part of the city and as the builders of urban identity. The article initially explores the changes in describing and interpreting urban peripheries, showing how they must be related to actual changes in urban settlement dynamics, as well as to changes in the theoretical frameworks used to understand the phenomenon of the Italian ‘urban periphery’. The article then shows how changes in interpretation have redefined the objectives and methods of policy interventions in the Italian context. Finally, certain critical issues will be discussed, in particular the origins of urban renewal policies and their recent evolution; the redefinition of the local authority role, and the relationships between institutional and social projects and activities. In this view, institutional projects are considered to be the formal projects carried out by public actors, for example municipalities, in order to manage the change in urban peripheries while social projects are understood as the informal practices of inhabitants of peripheries that change their living neighbourhoods.  相似文献   
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Osteoarthritis is the most common human arthritis characterized by degeneration of articular cartilage. Several studies reported that levels of human cartilage glycoprotein chitinase 3-like-1 (CHI3L1) are known as a potential marker for the activation of chondrocytes and the progression of Osteoarthritis (OA), whereas lubricin appears to be chondroprotective. The aim of this study was to investigate the co-expression and co-localization of CHI3L1 and lubricin in normal and osteoarthritic rat articular cartilage to correlate their modified expression to a specific grade of OA. Samples of normal and osteoarthritic rat articular cartilage were analyzed by the Kellgren–Lawrence OA severity scores, the Kraus’ modified Mankin score and the Histopathology Osteoarthritis Research Society International (OARSI) system for histomorphometric evaluations, and through CHI3L1 and lubricin gene expression, immunohistochemistry and double immuno-staining analysis. The immunoexpression and the mRNA levels of lubricin increased in normal cartilage and decreased in OA cartilage (normal vs. OA, p < 0.01). By contrast, the immunoexpression and the mRNA levels of CHI3L1 increased in OA cartilage and decreased in normal cartilage (normal vs. OA, p < 0.01). Our findings are consistent with reports suggesting that these two glycoproteins are functionally associated with the development of OA and in particular with grade 2/3 of OA, suggesting that in the future they could be helpful to stage the severity and progression of the disease.  相似文献   
79.
Most studies on surface-initiated controlled polymerizations for the synthesis of polymeric covalent organic-inorganic hybrid materials focus on chemical methods requiring specific modifications of the inorganic substrate. Few mechanistically-aware approaches have been undertaken towards exploiting the reactivity of defects induced by physical techniques such as ionizing radiations or UV–Vis light. Within this framework, we take grafted polymerization of styrene from γ-irradiated silica as a mechanistic testing ground where para- and diamagnetic silica defects are present, and polymerization proceeds through both radical and cationic mechanisms, resulting in a bimodal molecular weight distribution. We show that these mechanistic intricacies can be sorted out by resorting to the chemical arsenal developed in the last decades for controlled polymerizations. Specifically, we obtained a silica-polystyrene grafted material by cationic grafting from at 30 °C, a unimodal molecular weight distribution, and a relatively high molecular weight (Mn = 7.4 kDa) with a PDI of 1.68.  相似文献   
80.
The cerebral synthesis of cholesterol is mainly handled by astrocytes, which are also responsible for apoproteins’ synthesis and lipoproteins’ assembly required for the cholesterol transport in the brain parenchyma. In Alzheimer disease (AD), these processes are impaired, likely because of the astrogliosis, a process characterized by morphological and functional changes in astrocytes. Several ATP-binding cassette transporters expressed by brain cells are involved in the formation of nascent discoidal lipoproteins, but the effect of beta-amyloid (Aβ) assemblies on this process is not fully understood. In this study, we investigated how of Aβ1-42-induced astrogliosis affects the metabolism of cholesterol in vitro. We detected an impairment in the cholesterol efflux of reactive astrocytes attributable to reduced levels of ABCA1 transporters that could explain the decreased lipoproteins’ levels detected in AD patients. To approach this issue, we designed biomimetic HDLs and evaluated their performance as cholesterol acceptors. The results demonstrated the ability of apoA-I nanodiscs to cross the blood–brain barrier in vitro and to promote the cholesterol efflux from astrocytes, making them suitable as a potential supportive treatment for AD to compensate the depletion of cerebral HDLs.  相似文献   
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