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101.
Federico Cugurullo 《城市工程杂志》2013,20(1):23-37
Fuelled by an increasing diffusion of “green-consciousness” in urban politics, the eco-city has recently gained momentum. In the last decade, several governments from different areas of the world have approved plans for the construction of new master-planned urban developments aiming to find a balance with nature. The eco-city phenomenon is inscribed in a critical spatio-temporal context and its effects will arguably have a strong influence on our near future. Today, cities drain most of the global resources, have a major impact on the environment, and attract an increasing percentage of the world's population. Should the mainstream projections on 2050 prove to be correct, what we build now is and will be of primary importance. Hence, it is time to bring our current paradigms into question. This paper acknowledges the popularity that the eco-city has achieved in planning and mainstream discourses on sustainable development and aims to develop an understanding of the phenomenon on the basis of empirical analysis. More specifically, the paper focuses on the nexus between eco-cities and sustainability ideology to show how the latter is understood and applied in the development of new settlements. Using Masdar City as a case study, the three canonic dimensions of sustainability: the economic, the social, and the environmental, are here explored, and their respective weight evaluated. Ultimately, it will be shown how the foundations of the eco-city are strongly grounded in economic concerns and how the social and environmental aspects form only a layer aiming to hide the real nature of the phenomenon. 相似文献
102.
Federico Cova Pierre Arneodo LarochetteFabiana Gennari 《International Journal of Hydrogen Energy》2012
In the present work we investigate the hydrogen sorption properties of composites in the MgH2–Ni, MgH2–Ni–LiH and MgH2–Ni–LiBH4 systems and analyze why Ni addition improve hydrogen sorption rates while LiBH4 enhance the hydrogen storage capacity. Although all composites with Ni addition showed significantly improved hydrogen storage kinetics compared with the pure MgH2, the fastest hydrogen sorption kinetics is obtained for Ni-doped MgH2. The formation of Mg2Ni/Mg2NiH4 in Ni-doped MgH2 composite and its microstructure allows to uptake 5.0 wt% of hydrogen in 25 s and to release it in 8 min at 275 °C. In the MgH2–Ni–LiBH4 composite, decomposition of LiBH4 occurs during the first dehydriding leading to the formation of diborane, which has a Ni catalyst poison effect via the formation of a passivating boron layer. A combination of FTIR, XRD and volumetric measurements demonstrate that the formation of MgNi3B2 in the MgH2–Ni–LiBH4 composite happens in the subsequent hydriding cycle from the reaction between Mg2Ni/Mg2NiH4 and B. Activation energy analysis demonstrates that the presence of Ni particles has a catalytic effect in MgH2–Ni and MgH2–Ni–LiH systems, but it is practically nullified by the addition of LiBH4. The beneficial role of LiBH4 on the hydrogen storage capacity of the MgH2–Ni–LiBH4 composite is discussed. 相似文献
103.
Federico Felici Author Vitae Jan-Willem van Wingerden Author Vitae Author Vitae 《Automatica》2007,43(10):1684-1697
A novel subspace identification method is presented which is able to reconstruct the deterministic part of a multivariable state-space LPV system with affine parameter dependence, in the presence of process and output noise. It is assumed that the identification data is generated with the scheduling variable varying periodically during the course of the identification experiment. This allows to use methods from LTI subspace identification to determine the column space of the time-varying observability matrices. It is shown that the crucial step in determining the original LPV system is to ensure the obtained observability matrices are defined with respect to the same state basis. Once the LPV model has been identified, it is valid for other nonperiodic scheduling sequences as well. 相似文献
104.
Sabrina Caporali Biagio Didona Mauro Paradisi Alessandro Mauriello Elena Campione Mattia Falconi Federico Iacovelli Marilena Minieri Massimo Pieri Sergio Bernardini Alessandro Terrinoni 《International journal of molecular sciences》2021,22(13)
Palmoplantar keratodermas (PPKs) are characterized by thickness of stratum corneum and epidermal hyperkeratosis localized in palms and soles. PPKs can be epidermolytic (EPPK) or non epidermolytic (NEPPK). Specific mutations of keratin 16 (K16) and keratin 1 (K1) have been associated to EPPK, and NEPPK. Cases of mosaicism in PPKs due to somatic keratin mutations have also been described in scientific literature. We evaluated a patient presenting hyperkeratosis localized monolaterally in the right palmar area, characterized by linear yellowish hyperkeratotic lesions following the Blaschko lines. No other relatives of the patient showed any dermatological disease. Light and confocal histological analysis confirmed the presence of epidermolityic hyperkeratosis. Genetic analysis performed demonstrates the heterozygous deletion :r.274_472del for a total of 198 nucleotides, in KRT1 cDNA obtained by a palmar lesional skin biopsy, corresponding to the protein mutation NM_006121.4:p.Gly71_Gly137del. DNA extracted from peripheral blood lymphocytes did not display the presence of the mutation. These results suggest a somatic mutation causing an alteration in K1 N-terminal variable domain (V1). The deleted sequence involves the ISIS subdomain, containing a lysine residue already described as fundamental for epidermal transglutaminases in the crosslinking of IF cytoskeleton. Moreover, a computational analysis of the wild-type and V1-mutated K1/K10 keratin dimers, suggests an unusual interaction between these keratin filaments. The mutation taster in silico analysis also returned a high probability for a deleterious mutation. These data demonstrate once again the importance of the head domain (V1) of K1 in the formation of a functional keratinocyte cytoskeleton. Moreover, this is a further demonstration of the presence of somatic mutations arising in later stages of the embryogenesis, generating a mosaic phenotype. NP_006112.3相似文献
105.
Ana Santos-Gmez Federico Miguez-Cabello Natalia Juli-Palacios Deyanira García-Navas Víctor Soto-Insuga Juan J. García-Peas Patricia Fuentes Salvador Ibez-Mic Laura Cuesta Ramn Cancho Patricia Andreo-Lillo Gema Gutirrez-Aguilar Olga Alonso-Luengo Ignacio Mlaga Antonio Hedrera-Fernndez ngels García-Cazorla David Soto Mireia Olivella Xavier Altafaj 《International journal of molecular sciences》2021,22(23)
Background: GRIN-related disorders (GRD), the so-called grinpathies, is a group of rare encephalopathies caused by mutations affecting GRIN genes (mostly GRIN1, GRIN2A and GRIN2B genes), which encode for the GluN subunit of the N-methyl D-aspartate (NMDA) type ionotropic glutamate receptors. A growing number of functional studies indicate that GRIN-encoded GluN1 subunit disturbances can be dichotomically classified into gain- and loss-of-function, although intermediate complex scenarios are often present. Methods: In this study, we aimed to delineate the structural and functional alterations of GRIN1 disease-associated variants, and their correlations with clinical symptoms in a Spanish cohort of 15 paediatric encephalopathy patients harbouring these variants. Results: Patients harbouring GRIN1 disease-associated variants have been clinically deeply-phenotyped. Further, using computational and in vitro approaches, we identified different critical checkpoints affecting GluN1 biogenesis (protein stability, subunit assembly and surface trafficking) and/or NMDAR biophysical properties, and their association with GRD clinical symptoms. Conclusions: Our findings show a strong correlation between GRIN1 variants-associated structural and functional outcomes. This structural-functional stratification provides relevant insights of genotype-phenotype association, contributing to future precision medicine of GRIN1-related encephalopathies. 相似文献
106.
Scintillation and beam-wander analysis in an optical ground station-satellite uplink 总被引:4,自引:0,他引:4
In an optical communication link between an optical ground station and a geostationary satellite the main problems appear in the uplink and are due to beam wander and to scintillation. Reliable methods for modeling both effects simultaneously are needed to provide an accurate tool with which the robustness of the communication channel can be tested. Numerical tools, especially the split-step method (also referred to as the fast-Fourier-transform beam propagation method), have demonstrated their ability to deal with problems of optical propagation during atmospheric turbulence. However, obtaining statistically significant results with this technique is computationally intensive. We present an analytical-numerical hybrid technique that provides good information on the variance in optical irradiance with an important saving of time and computational resources. 相似文献
107.
Luca Tosatto Federico Mella Marshall B. Long Mitchell D. Smooke 《Combustion and Flame》2012,159(10):3027-3039
The structure of a JP-8 coflow flame is investigated by applying laser diagnostic techniques to three different fuel surrogates. The results are compared against theoretical predictions from numerical simulations; very good agreement is obtained for temperature and major species.Rayleigh and Raman scattering are used to measure temperature and major species mole fractions in the flame (oxygen, carbon dioxide, water, and fuel molecules). Quantitative laser diagnostic techniques are particularly challenging when applied to jet-fuel flames; the presence of aromatic molecules in the fuel mixtures and the formation of polyaromatic compounds inside the flame generate spectrally broad fluorescence signals that interfere with the measurement. A polarized/depolarized subtraction technique combined with a post-processing filter based on least-squares fitting is used to mitigate this undesired effect. The proposed technique tries to match the experimental signal against previously calculated spectra and has proved to be a very efficient filter at rejecting polyaromatic fluorescence.Numerical simulations play a fundamental role in this study. Computer predictions are used not only to compare experimental data, but as an active component of the data post-processing. For example, numerically calculated cross-section maps are used to refine the measured temperature for both the Rayleigh and Raman experiments. 相似文献
108.
Alessandro Dama Federico Lastaria 《International Journal of Heat and Mass Transfer》2012,55(13-14):3829-3833
The paper presents an explicit formulation of the radiative problem in gray enclosures. The method is based on a series expansion that derives the mutual radiation factors by means of summation of the contributions to the radiative thermal exchange given by the multi-reflection process. A mathematical proof that the infinite expansion converges to the well known solution, given by the implicit formulation and based on radiosities balance, is provided. Moreover a parametric analysis of the approximation induced by the explicit algorithm, as a result of the truncation order in the calculation of the series expansion, is carried out. The analysis shows how the precision of every approximation order is mainly related to the surface averaged infrared reflectance and is weakly dependent on the reflectance distribution. For high emissive and low reflecting surfaces, very few summations are required to meet high precision; the same level of precision is achievable also with medium and high reflecting surfaces, by increasing the truncation order of the series. More generally, the explicit formulation provides an alternative approach to problems involving multi-reflecting cavities in different engineering applications, from heat transfer to optics. 相似文献
109.
Zhao Yongheng Fang Guangchi Guo Yulan Guibas Leonidas Tombari Federico Birdal Tolga 《International Journal of Computer Vision》2022,130(9):2321-2336
International Journal of Computer Vision - We present 3DPointCaps++ for learning robust, flexible and generalizable 3D object representations without requiring heavy annotation efforts or... 相似文献
110.
Anisse Pereira Hong C. Lee Robert Lammert Jr. Cailyn Wolberg Jr. Danyi Ma Chad Immoos Federico Casassa Iksoon Kang 《International Journal of Food Science & Technology》2022,57(3):1814-1823
This study was conducted to evaluate the effect of red-wine grape pomaces on the quality and sensory attributes of beef hamburger patties. Both phenolic content and antioxidant activity were assessed using Syrah, Merlot and Cabernet Sauvignon pomaces. Following the assessment, hamburger patties were prepared with Merlot pomace at 0%, 2% and 4% for the patty quality and sensory attributes. Grape seeds possessed significantly higher phenolics and antioxidant activities over the seedless pomace (P < 0.05), whereas no significant difference was found for phenolics and antioxidant activities within the seeds and seedless pomaces. The patty pH decreased as the pomace was added for 2% and 4%. Colour values (L*, a* and b*) of patties lowered as the pomace was added. Allo-Kramer shear force and hardness values increased while cooking yield decreased (P < 0.05) with the addition of pomace. No significant difference between control and Merlot patties was found for flavour, juiciness and colour, whereas lower sensory attributes were observed for texture, taste and overall acceptability. It is observed that the addition of fermented red-wine grape pomace provides hamburger patties with health promoting factors such as antioxidant and other functional components, but it also provided darker, sourer and lower cooking yield. 相似文献