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排序方式: 共有919条查询结果,搜索用时 15 毫秒
1.
Virginia Veronica Visconti Ida Cariati Simona Fittipaldi Riccardo Iundusi Elena Gasbarra Umberto Tarantino Annalisa Botta 《International journal of molecular sciences》2021,22(8)
DNA methylation is one of the most studied epigenetic mechanisms that play a pivotal role in regulating gene expression. The epigenetic component is strongly involved in aging-bone diseases, such as osteoporosis and osteoarthritis. Both are complex multi-factorial late-onset disorders that represent a globally widespread health problem, highlighting a crucial point of investigations in many scientific studies. In recent years, new findings on the role of DNA methylation in the pathogenesis of aging-bone diseases have emerged. The aim of this systematic review is to update knowledge in the field of DNA methylation associated with osteoporosis and osteoarthritis, focusing on the specific tissues involved in both pathological conditions. 相似文献
2.
This study, which is based on responses from over 300 individuals in England and Wales, explores how a willingness to use a water-recycling system of specific configuration varies against a number of factors which are linked to system design, system scale, system context, and water-conservation behaviour. Findings show that there is broad willingness to accept in-house water recycling provided that public health is not compromised. 相似文献
3.
Building kernels from binary strings for image matching. 总被引:1,自引:0,他引:1
Francesca Odone Annalisa Barla Alessandro Verri 《IEEE transactions on image processing》2005,14(2):169-180
In the statistical learning framework, the use of appropriate kernels may be the key for substantial improvement in solving a given problem. In essence, a kernel is a similarity measure between input points satisfying some mathematical requirements and possibly capturing the domain knowledge. In this paper, we focus on kernels for images: we represent the image information content with binary strings and discuss various bitwise manipulations obtained using logical operators and convolution with nonbinary stencils. In the theoretical contribution of our work, we show that histogram intersection is a Mercer's kernel and we determine the modifications under which a similarity measure based on the notion of Hausdorff distance is also a Mercer's kernel. In both cases, we determine explicitly the mapping from input to feature space. The presented experimental results support the relevance of our analysis for developing effective trainable systems. 相似文献
4.
Water turbidity, surface temperature and circulation of Barton and Wroxham Broads, two of the Norfolk Broads, were studied using one reflective (TM1) and the thermal (TM6) TM band. The results indicated that the through-flowing path of the River Ant in Barton Broad is the major influence on the distribution of these parameters. In Wroxham Broad, both turbidity and surface temperature displayed a uniform distribution. This could be explained by the absence of a predominant direction of flow. 相似文献
5.
P. Worrall BEd MSc K. Peberdy BSc MSc H. McGinn BSc MSc 《Water and Environment Journal》1998,12(2):86-91
In 1993, the Wildfowl and Wetlands Trust constructed a demonstration reedbed treatment system at its Castle Espie Visitor Centre in Northern Ireland. The objectives of the project included (a) the treatment of septic-tank effluent, (b) the protection of water quality in Strangford Lough, and (c) the establishment of a research base for constructed wetland systems. Parallel beds of equally sized sub-surface and surface flow were constructed and planted, and a research project was initiated to provide data on performance. 相似文献
6.
/ CRAG MSc Project Team 《The International Journal of Advanced Manufacturing Technology》1985,1(1):55-71
Cranfield Robotics and Automation Group (CRAG) in collaboration with Texas Instruments (UK) manufacturing systems research
group has built a flexible machining cell and established computer integrated manufacturing support facilities to demonstrate
a low-cost, modular system of machine-to-computer communication. 相似文献
7.
L. Fewtrell BSc MSc PhD D. Kay BSc PhD A. Godfree BSc 《Water and Environment Journal》1998,12(1):45-47
This paper provides a detailed assessment of the microbiological quality of a selection of private water supplies. Samples were taken from 91 supplies and analyzed for total coliforms, faecal coliforms and faecal streptococci. The microbiological quality of the samples was generally poor, with almost 50% of the supplies failing to meet the required standards on at least one occasion. Given the high level of sanitary microbiological failures, there is the possibility that harmful microorganisms could be present and a significant risk to health cannot be discounted. 相似文献
8.
This study sought to examine patterns of changes of psychological stress symptoms in autologous bone marrow transplantation (ABMT) recipients. Forty-nine patients affected by solid tumors were assessed using the Symptom Questionnaire on admission to hospital (before high-dose chemotherapy and ABMT) and before discharge. Symptoms of anxiety and anger tended to decrease and relaxation of improve over time. Nevertheless, on admission to hospital 30-50% of the patients reported severe to moderate symptoms of anxiety and depression. Before discharge, the prevalence was still high (20-35%). The implications of these findings are discussed in terms of the need to monitor the evolution of emotional functioning of cancer patients undergoing ABMT. 相似文献
9.
SARAH L. LONGSTAFF BSc MSc FGS P. J. ALDOUS BSc PhD FGS L. CLARK BSc PhD CGeol R. J. FLAVIN BSc CGeol J. PARTINGTON 《Water and Environment Journal》1992,6(6):541-550
A detailed investigation of contamination by chlorinated solvents of the Chalk Aquifer underlying the towns of Luton and Dunstable was undertaken to assess the extent, causes and mechanisms of pollution. The research programme incorporated land-use surveys, regional groundwater surveys, monitoring of groundwater abstraction points and aquifer profiling by means of the drilling of observation boreholes, the analysis of the recovered core material and the depth sampling of these and other boreholes.
Low-level solvent contamination of the Chalk Aquifer was found to be widespread with 'hotspots'of higher concentrations. At the drilling sites, both the saturated and unsaturated zones were contaminated with solvents, although free product was not observed. The presence of an additional contaminant, oil, at some sites was noted to influence the distribution of solvents within the aquifer.
Clean-up of the aquifer is not a practical option, and treatment of the groundwater at the abstraction points has been adopted. 相似文献
Low-level solvent contamination of the Chalk Aquifer was found to be widespread with 'hotspots'of higher concentrations. At the drilling sites, both the saturated and unsaturated zones were contaminated with solvents, although free product was not observed. The presence of an additional contaminant, oil, at some sites was noted to influence the distribution of solvents within the aquifer.
Clean-up of the aquifer is not a practical option, and treatment of the groundwater at the abstraction points has been adopted. 相似文献
10.
Laura Menabò Alessandra Sansavini Antonella Brighi Grace Skrzypiec Annalisa Guarini 《Journal of Computer Assisted Learning》2021,37(6):1566-1577
Background: The rapid spread of COVID-19 forced many countries to adopt severe containment measures, transferring all didactic activities into virtual environments. However, the integration of technology in teaching may present difficulties, especially in some countries, such as Italy. Objectives: The present study analyzed how the two main factors of the Technology Acceptance Model (TAM), namely perceived usefulness and perceived ease of use, combined with online teaching self-efficacy, were associated with the intention to use technology to teach. We posited a moderated moderation model in which perceived usefulness represented the main predictor, with self-efficacy and perceived ease of use as moderators of intention to use technology to teach. Method: The model was tested through multiple regressions, using the PROCESS macro on SPSS 26 with a sample of 178 upper secondary school teachers in Italy. Results and conclusions: Regressions showed that each variable significantly predicted the intention to use technology. In addition, a moderation effect of self-efficacy on the perceived usefulness of using technology was found for medium and high-level of perceived ease of use of technology. Implications: The present study provides targeted implications for distance education policy and practice to promote its adoption (or the blended modality) in Italian upper schools. 相似文献