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41.
Introduction to the Special Issue on Meta-Learning 总被引:1,自引:0,他引:1
Recent advances in meta-learning are providing the foundations to construct meta-learning assistants and task-adaptive learners. The goal of this special issue is to foster an interest in meta-learning by compiling representative work in the field. The contributions to this special issue provide strong insights into the construction of future meta-learning tools. In this introduction we present a common frame of reference to address work in meta-learning through the concept of meta-knowledge. We show how meta-learning can be simply defined as the process of exploiting knowledge about learning that enables us to understand and improve the performance of learning algorithms. 相似文献
42.
Baptiste Wilmet Jacques Callebert Robert Duvoisin Ruben Goulet Christophe Tourain Christelle Michiels Helen Frederiksen Frank Schaeffel Olivier Marre Jos Alain Sahel Isabelle Audo Serge Picaud Christina Zeitz 《International journal of molecular sciences》2023,24(1)
Mutations in GPR179 are one of the most common causes of autosomal recessive complete congenital stationary night blindness (cCSNB). This retinal disease is characterized in patients by impaired dim and night vision, associated with other ocular symptoms, including high myopia. cCSNB is caused by a complete loss of signal transmission from photoreceptors to ON-bipolar cells. In this study, we hypothesized that the lack of Gpr179 and the subsequent impaired ON-pathway could lead to myopic features in a mouse model of cCSNB. Using ultra performance liquid chromatography, we show that adult Gpr179−/− mice have a significant decrease in both retinal dopamine and 3,4-dihydroxyphenylacetic acid, compared to Gpr179+/+ mice. This alteration of the dopaminergic system is thought to be correlated with an increased susceptibility to lens-induced myopia but does not affect the natural refractive development. Altogether, our data added a novel myopia model, which could be used to identify therapeutic interventions. 相似文献
43.
Shreyasee Das Nele Dewit Dirk Jacobs Yolande A. L. Pijnenburg Sjors G. J. G. In t Veld Salom Coppens Milena Quaglia Christophe Hirtz Charlotte E. Teunissen Eugeen Vanmechelen 《International journal of molecular sciences》2022,23(13)
Neurofilament light chain (Nf-L) is a well-known biomarker for axonal damage; however, the corresponding circulating Nf-L analyte in cerebrospinal fluid (CSF) is poorly characterized. We therefore isolated new monoclonal antibodies against synthetic peptides, and these monoclonals were characterized for their specificity on brain-specific intermediate filament proteins. Two highly specific antibodies, ADx206 and ADx209, were analytically validated for CSF applications according to well-established criteria. Interestingly, using three different sources of purified Nf-L proteins, a significant impact on interpolated concentrations was observed. With a lower limit of analytical sensitivity of 100 pg/mL using bovine Nf-L as the calibrator, we were able to quantify the Nf-L analyte in each sample, and these Nf-L concentrations were highly correlated to the Uman diagnostics assay (Spearman rho = 0.97, p < 0.001). In the clinical diagnostic groups, the new Nf-L ELISA could discriminate patients with Alzheimer’s disease (AD, n = 20) from those with frontotemporal lobe dementia (FTD, n = 20) and control samples with subjective cognitive decline (SCD, n = 20). Henceforth, this novel Nf-L ELISA with well-defined specificity and epitopes can be used to enhance our understanding of harmonizing the use of Nf-L as a clinically relevant marker for neurodegeneration in CSF. 相似文献
44.
三相异步电机新模型及其仿真与实验 总被引:11,自引:2,他引:11
介绍了三相异步电机的一个新模型。新模型由原始的相轴线模型经过变换得到。该模型可应用在电机定子三相参数不对称的状态。计算机仿真和电机模拟实验表明:在派克方程适用范围,新模型与PARK模型的响应完全一致:当电机定子三相参数不对称时,此时已超出PARK模型的适用范围,新模型的仿真计算结果与电机的实验数据相当吻合。新模型具有比PARK模型更广的适用范围。该模型在三相异步电机的监测及控制方面有广泛的应用前景。 相似文献
45.
Saint Martin Marie-Judith Orlhac Fanny Akl Pia Khalid Fahad Nioche Christophe Buvat Irène Malhaire Caroline Frouin Frédérique 《Magma (New York, N.Y.)》2021,34(3):355-366
Magnetic Resonance Materials in Physics, Biology and Medicine - Quantitative analysis in MRI is challenging due to variabilities in intensity distributions across patients, acquisitions and... 相似文献
46.
47.
Fabrice Roussière Christophe Baley Grégory Godard Dominique Burr 《Applied Composite Materials》2012,19(2):171-188
Nowadays, the ecological footprint of a material is becoming tremendously important. The Poly l-Lactide Acid (PLLA) matrix
composites reinforced by randomly scattered flax fibres have mechanical properties similar to polyester/glass composites [1], lower environmental impacts and can be compost at the end of their lives. In this study, the mechanical characterization
of biocomposites has been pushed further with the determination of the compressive and tensile properties. Furthermore, the
mechanical properties of single flax fibres have been measured and implemented in a micro-mechanical estimation of the composite
elastic modulus. Tensile and compressive stiffness determined by the mechanical analyses show very good correlations with
the mathematical estimation. 相似文献
48.
Innovation-based strategies are widely recognized as key drivers to maintain competitive advantage. The design and strategic literature underline the possibility of triggering a multiproduct value-expansion dynamic based on the creation of new concepts dynamically twinned with corporate strategy. However, the multiproject-management literature—portfolio, program, and platform—lags behind and remains focused on ex ante coordination, resource allocation and selectionism. Thus, there are still few indications of the processes that stimulate and orient continuous, profitable multiproject creative expansion. Bridging the multiproject-management literature and design theory, we propose a model of multiproject lineage management (MPLM), which focuses on the key processes that drive exploration efforts and shape innovation trajectory. We conduct a multiple longitudinal case analysis in the automobile sector. Based on this analysis, we expose the principles of MPLM, mapping the roles of corporate, program and project management within a global expansion project. Finally, we highlight our contributions to managerial practices and the related literature. 相似文献
49.
50.
Marie Hurtgen Antoine Debuigne Didier Gigmes Christine Jérôme Christophe Detrembleur 《Polymer》2012,53(20):4353-4358
The grafting mechanism of poly(vinyl acetate) macroradicals prepared by cobalt-mediated radical polymerization onto C60 is investigated. The experimental conditions directly impact the nature and stability of the PVAc/C60 adducts. In the presence of residual initiating radicals that can compete with PVAc° macroradicals for addition onto C60, mixtures of PVAc/C60 adducts having between one and eight polymer chains per C60 are formed. PVAc/C60 adducts prepared with low [PVAc]:[C60] ratios may contain weak C60–C60 bonds that further dissociate and account for the instability of the products. The formation of such dimers can be lessened by increasing the temperature from 30 °C to 100 °C. The temperature increase also allows a complete dissociation of the PVAc-Co dormant species into PVAc° macroradicals and an almost quantitative grafting of eight PVAc chains onto C60, leading to well-defined C60(PVAc)8 octa-adducts. These results might shed new light on the grafting onto C60 of macroradicals prepared by other CRP techniques. 相似文献