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991.
Giuseppe Anastasi Marco Conti Mario Di Francesco Andrea Passarella 《Ad hoc Networks》2009,7(3):537-568
In the last years, wireless sensor networks (WSNs) have gained increasing attention from both the research community and actual users. As sensor nodes are generally battery-powered devices, the critical aspects to face concern how to reduce the energy consumption of nodes, so that the network lifetime can be extended to reasonable times. In this paper we first break down the energy consumption for the components of a typical sensor node, and discuss the main directions to energy conservation in WSNs. Then, we present a systematic and comprehensive taxonomy of the energy conservation schemes, which are subsequently discussed in depth. Special attention has been devoted to promising solutions which have not yet obtained a wide attention in the literature, such as techniques for energy efficient data acquisition. Finally we conclude the paper with insights for research directions about energy conservation in WSNs. 相似文献
992.
Combined microwaves and convection heating: A conjugate approach 总被引:2,自引:0,他引:2
Microwave treatment has been gaining increasing recognitions in the food industry and household frameworks alike. Better energy and finishing efficiencies can be obtained by adding an additional transport mechanism, such as forced air convection heating. In this work, transient distributions of temperature and moisture during the combined treatment is analyzed by a full computational fluid dynamics model, coupled with custom moisture diffusion and evaporation notations. 相似文献
993.
Daghino S Turci F Tomatis M Favier A Perotto S Douki T Fubini B 《Environmental science & technology》2006,40(18):5793-5798
Some soil fungi growing on asbestos fibers release chelators and antioxidants. The bioweathering potential of fungi has thus been envisaged as a possible route for bioremediation of asbestos rich soils, where no inactivation procedures have been established so far. The present study reports fungal-mediated modification of the surface reactivity of the fibers and of their potential to damage DNA in vitro. Verticillium sp. and Paecilomyces sp. were selected among the fungi isolated from fragments of chrysotile bearing rocks, as the most potent in iron extraction, and studied in parallel with F. oxysporum, previously reported to modify the surface reactivity of asbestos fibers. One sample of chrysotile from the Western Alps and a sample of UICC (Union Internationale Contre le Cancer) crocidolite were incubated with or without fungi. All fungi extracted iron from both fibers (7.3% from crocidolite and 33.6% from chrysotile by Verticillium sp.), releasing it into the medium. F. oxysporum and Paecilomyces sp. suppressed the potential of the fibers to release hydroxyl radical, while Verticillium sp. suppressed it on crocidolite but enhanced it on chrysotile, a hallmark of ongoing mobilization of reactive iron. Fibers incubated in the growth medium, but in the absence of fungi, exhibited a remarkable potential to damage DNA in vitro, measured by the generation of 8-oxo-7,8-dihydro-2'-deoxyguanosine, while all the fungi reduced such effect. Fungi may thus be regarded as appropriate candidates for bioremediation of asbestos rich soils whereby the reactive iron ions responsible for DNA damage are progressively removed from the fibers. 相似文献
994.
Di Santo R Costi R Artico M Ragno R Lavecchia A Novellino E Gavuzzo E La Torre F Cirilli R Cancio R Maga G 《ChemMedChem》2006,1(1):82-95
TIBO- and TBO-like sulfone derivatives 1 and 2 were designed, synthesized, and tested for their ability to block the replication cycle of HIV-1 in infected cells. The anti-HIV-1 activities of sulfones 3, which were intermediates in the syntheses of 1 and 2, were also evaluated. Surprisingly, the sulfone analogues of TIBO R82913 (compounds 1) were inactive, whereas interesting results were obtained for truncated derivatives 2. Compound 2 w was the most potent among this series in cell-based assays (EC50=0.07 microM, CC50>200 microM, SI>2857). It was twofold less potent than R82913, but more selective. An X-ray crystallographic analysis was carried out to establish the absolute configuration of 2 w and its enantiomer 2 x, which were obtained by semipreparative HPLC of 2 v, one of the most potent racemates. Compounds 1-3 were proven to target HIV-1 RT. In fact, representative derivatives inhibited recombinant HIV-1 RT in vitro at concentrations similar to those active in cell-based assays. 3D QSAR studies and docking simulations were developed on TIBO- and TBO-like sulfone derivatives to rationalize their anti-HIV-1 potencies and to predict the activity of novel untested sulfone derivatives. Predictive 3D QSAR models were obtained with a receptor-based alignment by docking of TIBO- and TBO-like derivatives into the NNBS of RT. 相似文献
995.
Andrea Zambotti Mattia Biesuz Mauro Bortolotti Andrea Dorigato Francesco Valentini Giulia Fredi Gian Domenico Sorarù 《International Journal of Applied Ceramic Technology》2023,20(1):39-50
Thermal energy storage (TES) with phase change materials (PCMs) presents some advantages when shape-stabilization is performed with ceramic aerogels. These low-density and ultra-porous materials guarantee high energy density and can be easily regenerated through simple pyrolysis while accounting for moderate mechanical properties. However, the small pore size that typically characterizes these sorbents can hinder the crystallization of PCMs, slightly reducing the energy density of the stabilized compound. In this work, we present the use of polymer-derived mesoporous SiC and SiOC aerogels for the stabilization of polyethylene glycol and a fatty alcohol (PureTemp 23), having a melting temperature of 17 and 23°C, respectively. Their TES performances point out maximum thermal efficiency values of around 80%. These performances are discussed accounting for the results of thermogravimetric analysis, differential scanning calorimetry, and leaking tests. 相似文献
996.
Antonella Pasqualone Samuela Palombieri Hamit Koksel Carmine Summo Pasquale De Vita Francesco Sestili 《International Journal of Food Science & Technology》2023,58(1):268-278
Faridur is the first ‘soft kernel’ durum wheat variety released in Italy. This variety has not yet been evaluated for its end-use quality. In the present study, the milling performance (using two different mills) and bread-making ability of Faridur were compared with Svevo. An effect of the mill type on flour properties was observed, with the Chopin CD1 mill leading to finer particle size, higher starch damage and water absorption than Bühler MLU 202. Protein and gluten content was significantly higher in Faridur, but gluten quality was lower, as indicated by alveograph and farinograph analyses. The softer nature of Faridur facilitated milling, reducing energy consumption and starch damage. The baking test led to a compact product, with low specific volume, needing adjustments in processing and formulation. As energy saving has become a key competitive factor in the milling sector, Faridur has potential for expanding the use of durum wheat. 相似文献
997.
Nasim Eslamirad Francesco De Luca Kimmo Sakari Lylykangas Sadok Ben Yahia 《建筑学研究前沿(英文版)》2023,12(3):541-555
Predicting comfort levels in cities is challenging due to the many metric assessment. To overcome these challenges, much research is being done in the computing community to develop methods capable of generating outdoor comfort data. Machine Learning (ML) provides many opportunities to discover patterns in large datasets such as urban data. This paper proposes a data-driven approach to build a predictive and data-generative model to assess outdoor thermal comfort. The model benefits from the results of a study, which analyses Computational Fluid Dynamics (CFD) urban simulation to determine the thermal and wind comfort in Tallinn, Estonia. The ML model was built based on classification, and it uses an opaque ML model. The results were evaluated by applying different metrics and show us that the approach allows the implementation of a data-generative ML model to generate reliable data on outdoor comfort that can be used by urban stakeholders, planners, and researchers. 相似文献
998.
Lorena Baranda Pellejero Minke A. D. Nijenhuis Francesco Ricci Kurt V. Gothelf 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(13):2200971
DNA-templated chemical reactions have found wide applications in drug discovery, programmed multistep synthesis, nucleic acid detection, and targeted drug delivery. The control of these reactions has, however, been limited to nucleic acid hybridization as a means to direct the proximity between reactants. In this work a system capable of translating protein–protein binding events into a DNA-templated reaction which leads to the covalent formation of a product is introduced. Protein-templated reactions by employing two DNA-antibody conjugates that are both able to recognize the same target protein and to colocalize a pair of reactant DNA strands able to undergo a click reaction are achieved. Two individual systems, each responsive to human serum albumin (HSA) and human IgG, are engineered and it is demonstrated that, while no reaction occurs in the absence of proteins, both protein-templated reactions can occur simultaneously in the same solution without any inter-system crosstalk. 相似文献
999.
Amir Hossein Khodabandehloo Mehrab Pourmadadi Amin Shamsabadipour Hadis Langari Amanda-Lee Manicum Abbas Rahdar Francesco Baino 《Journal of the American Ceramic Society》2023,106(9):5111-5132
There are diverse diseases such as some infections, trauma, and tumor resections during cancer surgery that can cause bone damage or skeletal defects in persons. Most of the time, these defects cannot heal spontaneously due to several medical conditions that patients encounter, like diabetes, hormone-related problems, and autoimmune disorders. This issue is even worse for older people and some special treatments should be provided for them. Bone-tissue engineering has emerged to tackle these challenges. By investigating bone repair strategies, studying bone structures and biomechanics, and employing appropriate growth factors, suitable scaffolds, and biomaterial-centered regenerative approaches can be employed to treat bone defects more effectively. This study reviews some recent bone-tissue-engineering strategies relying on two-dimensional (2D) materials, including graphene and its derivatives, black phosphorus, and MXenes that are exhibiting a great potential in regenerative medicine. 相似文献
1000.
Antonio Francesco Mottese Giuseppe Sabatino Marcella Di Bella Maria Rita Fede Francesco Parisi Giuseppe Marcianò Alessandro Tripodo Francesco Italiano Giacomo Dugo Francesco Caridi 《International Journal of Food Science & Technology》2021,56(6):2628-2639
This paper aims to define the stability over the time of chemical elemental patterns in some citrus varieties of PGI (Protected Geographical Indication) and not PGI Interdonato and Lunario cultivars coming from Italy and Turkey and to set up a range of markers useful to trace their geographical origin. During the 2015–2017 growing seasons, all fruits were collected and subjected to Inductively Coupled Mass spectrometry (ICP-MS) analysis, in order to determine the multielemental chemical profiles. The chemical variability was calculated for each element by Multi-way analysis of variance. The results highlighted how the measured Cr, Ni, Al, K, Fe and Zn levels mainly depend on the soil composition and the fingerprint allow to trace the geographical origins. Moreover, the stepwise linear discriminant analysis (SLDA) has allowed to correctly classify the 100% of lemon pulps provenances, based on Ni, Al, K, Ca and Na contents. Finally, our study demonstrates the role played by harvest years, variety and soils composition whose interaction contributed to define the chemical fingerprints. 相似文献