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61.
A new simple method (“line patterning technique”) using only standard office equipment is described whereby clearly defined, electrically conducting patterns of graphite can be deposited on polymer (plastic) or paper substrates. The properties of the conductive patterns have been characterized by electrical conductivity and SEM measurements. Sensors were constructed by using interdigitated patterns of graphite deposited on plastic and paper, and coated with a thin film of conducting electronic polymer, e.g. polyaniline emeraldine salt.  相似文献   
62.
In some animals, such as mice and guinea pigs, a hormonally controlled mechanism increases the flexibility of the pubic symphysis and enhances the cervical remodeling necessary for safe delivery. Cervical ripening during pregnancy is associated with a paradoxical influx of leukocytes. However, the changes in cell metabolism during relaxation of the mouse pubic symphysis for delivery have not been extensively studied. In this work, we used light microscopy and transmission and scanning electron microcopy, as well as immunohistochemistry and Western blotting for MMP-8, to investigate the involvement of granulocytes or resident stromal cells in the relaxation of the virgin pubic symphysis during late pregnancy (days 18 and 19, before delivery) in vivo and in explanted joints. MMP-8 was studied because this collagenase is a hallmark for cervical ripening associated with the influx of granulocytes during late pregnancy. Extensive dissolution and disorganization of the extracellular matrix was seen around fibroblastic-like cells in late pregnancy. In contrast to the cervix (positive control), morphological and immunohistochemical analyses revealed that there was no characteristic cellular inflammatory response in the interpubic tissue. Staining for MMP-8 was observed in chondroid and fibroblastic-like cells of virgin and relaxed interpubic ligament, respectively. However, no granulocytes were seen during the extensive remodeling of the pubic joint in late pregnancy. These results indicate that constitutive stromal cells may have an important role in tissue relaxation during remodeling of the pubic symphysis in pregnancy.  相似文献   
63.
We study the TiO2-BaO-ZnO-B2O3 glass system, where the ZnO and B2O3 compositions were constant and the ratio TiO2/BaO was varied from 0.87 to 1.76. A super kanthal resistance furnace was used to melt the compounds inside an alumina crucible, at 1200 °C, for 10 min. After melting, the glasses were poured out into steel moulds and rapidly cooled by quenching. The glasses obtained were homogeneous, bubble free and transparent. They were characterized by X-ray diffractometry, Fourier transform infrared spectroscopy (FTIR), UV-VIS spectroscopy, dilatometry, density and linear refractive index. An infrared cut off caused by the composition influence was found in both IR and UV-vis spectra. From dilatometry T d and T g were verified as being anomalous. The linear thermal expansion coefficient presented an anomalous behaviour in relation to TiO2 concentrations. The density and linear refractive index increased with increasing TiO2/BaO ratio arriving at their peak value of TiO2/BaO=1.5 and then decreasing. The dependence of softening point T d on the ratio TiO2/BaO exhibited the same behaviour. It is suggested that Ti4+ plays a dual part in the glass system, assuming a predominantly tetrahedral coordination in the low titania region and a predominantly octahedral coordination in the high titania region. With a heat treatment of the glass around 600 °C, we observed a rapid change of refractive index with increasing temperature.  相似文献   
64.
The sustainability framework has a strong influence on the policies, practices and procedures of companies. Green creativity plays a pivotal role in the development of initiatives and innovations for the environmental pillar of sustainability. Based on a survey applied to a Portuguese company with an accredited environmental management system (N = 146), the findings reveal that green creativity is influenced in different ways when analysed from distinct perspectives. The leader's green creativity is positively influenced by the subordinate's green self-efficacy and personal identification with the leader, whereas the subordinate's green creativity is positively influenced by their green passion and green self-efficacy, and the leaders' green creativity. This study shows that green creativity develops differentially according to distinct job positions and expectations that in practice must be complementary and synergistic for its effective development.  相似文献   
65.
66.

The classification task usually works with flat and batch learners, assuming problems as stationary and without relations between class labels. Nevertheless, several real-world problems do not assume these premises, i.e., data have labels organized hierarchically and are made available in streaming fashion, meaning that their behavior can drift over time. Existing studies on hierarchical classification do not consider data streams as input of their process, and thus, data is assumed as stationary and handled through batch learners. The same can be said about works on streaming data, as the hierarchical classification is overlooked. Studies concerning each area individually are promising, yet, do not tackle their intersection. This study analyzes the main characteristics of the state-of-the-art works on hierarchical classification for streaming data concerning five aspects: (i) problems tackled, (ii) datasets, (iii) algorithms, (iv) evaluation metrics, and (v) research gaps in the area. We performed a systematic literature review of primary studies and retrieved 3,722 papers, of which 42 were identified as relevant and used to answer the aforementioned research questions. We found that the problems handled by hierarchical classification of data streams include mainly classification of images, human activities, texts, and audio; the datasets are mostly created or synthetic data; the algorithms and evaluation metrics are well-known techniques or based on those; and research gaps are related to dynamic context, data complexity, and computational resources constraints. We also provide implications for future research and experiments to consider common characteristics shared amongst hierarchical classification and data stream classification.

  相似文献   
67.
The assessment of the social impacts of road traffic is usually based on objective indicators or on expert judgement, without input from the affected communities. This paper considers the perceptions and priorities of local residents about traffic impacts and possible mitigation measures, using as a case study a rural area that will be affected by traffic associated with the construction of a nuclear power station. The study consisted of a qualitative phase followed by a stated preference survey. Econometric models were used to measure the relative priority of different impacts and mitigation measures. The most impactful aspects were noise, vibration and increased car or bus travel times. The most preferred measures were night-time restrictions to HGVs, parking restrictions and safety measures for pedestrians and cyclists. There were significant differences in preferences according to residence location, gender, employment status and household composition. The results provide information about aspects that tend to be aggregated in existing assessment frameworks, separating the reduction in the utility of some activities (like walking and driving) and the suppression of those activities.  相似文献   
68.
69.
Mesoporous silica materials have demonstrated a vast spectrum of applications, stimulating an intensive field of study due to their potential use as nanocarriers. Nonetheless, when produced at the nanoscale, their structural characterization is hindered due to the re‐arrangement of the pores. To address this issue, this work combines molecular dynamics simulations with electron microscopy computer simulations and experimental results to provide an insight into the structure of amorphous mesoporous silica nanoparticles. The amorphous silica model is prepared using a simple melt‐quench molecular dynamics method, while the reconstruction of the mesoporous nanoparticles is carried out using a methodology to avoid false symmetry in the final model. Simulated scanning transmission electron microscopy images are compared with experimental images, revealing the existence of structural domains, created by the misalignment of the pores to compensate the surface tension of these spherical nanoparticles.  相似文献   
70.
The move to IP Protocol Television (IPTV) has challenged the traditional television industry by opening the Internet to high quality real time television content delivery. Thus it has provided an enabling set of key technologies to understand and foster further innovations in the multimedia landscape and to create dynamics in the TV value chain. This editorial provides a brief overview of this special issue. It begins with a short introduction to IPTV Technology and then summarizes the main contributions of the selected papers for this special issue, highlighting their salient features and novel results.  相似文献   
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