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排序方式: 共有756条查询结果,搜索用时 31 毫秒
101.
International Journal of Computer Vision - Clustering artworks is difficult for several reasons. On the one hand, recognizing meaningful patterns based on domain knowledge and visual perception is... 相似文献
102.
Vincenzo Andrea Montagna Stefano Palagi Giovanna Adele Naselli Carlo Filippeschi Barbara Mazzolai 《Advanced functional materials》2023,33(39):2214130
Annulus cells of fern sporangia spontaneously deform driven by water transpiration and cavitation, resulting in the peculiar macroscale catapult-like movement of the sporangium. Annulus cells' behavior, if artificially replicated, can inspire a novel class of fast actuators composed of annulus-mimicking units. However, the transpiration and cavitation-driven dynamics observed in annulus cells is never reproduced. Here, prismatic microcavities are assembled with a polydimethylsiloxane (PDMS) microfilm to realize artificial microchambers that mimic the annulus cells, replicating for the first time their evaporation-driven collapse and their fast return triggered by the nucleation of bubbles. The microchambers, in turn, can be fabricated in adjacency, resulting in bending arrays driven by transpiration. Working with an artificial system allows this study to investigate the fluidic phenomena arising from the interplay of a soft, semi-permeable membrane with a micro-confined liquid bounded by rigid walls. First, the microchambers aspect ratio influences the membrane dynamics and the bubble shape (either spherical or non-spherical). Second, the growth rate of the bubble interplay with the membrane in the expansion dynamics. This study's results demonstrate the artificial replication of annulus cells' behavior, offering a plant-like solution to realize fast, microscale movements, and a novel tool to investigate complex fluidic mechanisms involving micro-confined cavitation. 相似文献
103.
Patrizia Ferroni Raffaele Palmirotta Gabriella Egeo Cinzia Aurilia Maria Giovanna Valente Antonella Spila Alberto Pierallini Piero Barbanti Fiorella Guadagni 《International journal of molecular sciences》2022,23(22)
White matter hyperintensities (WMHs) in migraine could be related to inflammatory and antioxidant events. The aim of this study is to verify whether migraine patients with WMHs carry a genetic pro-inflammatory/pro-oxidative status. To test this hypothesis, we analyzed lymphotoxin alpha (LTA; rs2071590T and rs2844482G) and superoxide dismutase 1 (SOD1; rs2234694C) and 2 (SOD2; rs4880T) gene polymorphisms (SNPs) in 370 consecutive patients affected by episodic (EM; n = 251) and chronic (CM; n = 119) migraine and in unrelated healthy controls (n = 100). Brain magnetic resonance was available in 183/370 patients. The results obtained show that genotypes and allele frequencies for all tested SNPs did not differ between patients and controls. No association was found between single SNPs or haplotypes and sex, migraine type, cardiovascular risk factors or disorders. Conversely, the LTA rs2071590T (OR = 2.2) and the SOD1 rs2234694C (OR = 4.9) alleles were both associated with WMHs. A four-loci haplotype (TGCT haplotype: rs2071590T/rs2844482G/rs2234694C/rs4880T) was significantly more frequent in migraineurs with WMHs (7 of 38) compared to those without WMHs (4 of 134; OR = 8.7). We may, therefore, conclude by suggesting that that an imbalance between pro-inflammatory/pro-oxidative and antioxidant events in genetically predisposed individuals may influence the development of WMHs. 相似文献
104.
Bertanza G Pedrazzani R Dal Grande M Papa M Zambarda V Montani C Steimberg N Mazzoleni G Di Lorenzo D 《Water research》2011,45(8):2473-2484
A major source of the wide presence of EDCs (Endocrine Disrupting Compounds) in water bodies is represented by direct/indirect discharge of sewage. Recent scientific literature reports data about their trace concentration in water, sediments and aquatic organisms, as well as removal efficiencies of different wastewater treatment schemes. Despite the availability of a huge amount of data, some doubts still persist due to the difficulty in evaluating synergistic effects of trace pollutants in complex matrices. In this paper, an integrated assessment procedure was used, based on chemical and biological analyses, in order to compare the performance of two full scale biological wastewater treatment plants (either equipped with conventional settling tanks or with an ultrafiltration membrane unit) and tertiary ozonation (pilot scale).Nonylphenol and bisphenol A were chosen as model EDCs, together with the parent compounds mono- and di-ethoxylated nonylphenol (quantified by means of GC-MS). Water estrogenic activity was evaluated by applying the human breast cancer MCF-7 based reporter gene assay. Process parameters (e.g., sludge age, temperature) and conventional pollutants (e.g., COD, suspended solids) were also measured during monitoring campaigns.Conventional activated sludge achieved satisfactory removal of both analytes and estrogenicity. A further reduction of biological activity was exerted by MBR (Membrane Biological Reactor) as well as ozonation; the latter contributed also to decrease EDC concentrations. 相似文献
105.
Sebastiano Porretta Giovanna Poli 《International Journal of Food Science & Technology》1997,32(6):527-534
Summary The quality of tomato purèe prepared from transgenic fruits ( Lycopersicon esculentum ) which had reduced amounts of polygalacturonase (PG) activity, were evaluated. The application of genetic modification yields products which have lower Bostwick consistency values (from 35 to 55%), reduced serum separation ( c . 40%) and better sensory appearance and acceptability in comparison with their conventional counterparts. A new way of producing high quality tomato products using genetically modified fruits together with mild heat treatments is described. 相似文献
106.
Ida Cariati Roberto Bonanni Gabriele Pallone Cristian Romagnoli Anna Maria Rinaldi Giuseppe Annino Giovanna DArcangelo Virginia Tancredi 《International journal of molecular sciences》2022,23(18)
Whole body vibration (WBV) is well known to exert beneficial effects on multiple tissues, improving synaptic transmission, muscle mass, bone quality, and reducing anxiety and depressive behavior. However, the underlying molecular mechanisms are not yet fully understood, and organs and tissues may respond differently to the vibratory stimulus depending on multiple factors. Therefore, we investigated the WBV effects on the brain and musculoskeletal tissue of 4-month-old young mice, evaluating synaptic plasticity by electrophysiological recordings and tissue organization by histology and histomorphometric analysis. Specifically, WBV protocols were characterized by the same vibration frequency (45 Hz), but different in vibration exposure time (five series of 3 min for the B protocol and three series of 2 min and 30 s for the C protocol) and recovery time between two vibration sessions (1 min for the B protocol and 2 min and 30 s for the C protocol). In addition, immunohistochemistry was conducted to evaluate the expression of fibronectin type III domain-containing protein 5 (FNDC5), as well as that of tissue-specific markers, such as brain-derived neurotrophic factor (BDNF) in brain, myostatin in muscle and collagen I (COL-1) in bone. Our results suggest that the WBV effects depend closely on the type of protocol used and support the hypothesis that different organs or tissues have different susceptibility to vibration. Further studies will be needed to deepen our knowledge of physiological adaptations to vibration and develop customized WBV protocols to improve and preserve cognitive and motor functions. 相似文献
107.
ABSTRACT: The use of pulsed high hydrostatic pressure was investigated as a possible approach to stabilize foodstuffs. The objective of this article was to investigate the effect of the main processing variables (pressure [150 to 300 MPa], temperature levels [25 to 50 °C], and pulse number [1 to 10]) on the sanitation of nonpasteurized clear Annurca apple juice as well as freshly-squeezed clear orange juice. The aim of the article was the optimization of the process parameters in step-wise pressure treatment (pressure holding time of each pulse: 60 s, compression rate: 10.5 MPa/s, decompression time: 2 to 5s). The shelf life of the samples, processed at optimized conditions, was evaluated in terms of microbiological stability and quality retention. According to our experimental results, the efficiency of pulsed high pressure processes depends on the combination of pulse holding time and number of pulses. The pulsed high pressure cycles have no additive or synergetic effect on microbial count. The efficacy of the single pulses decreases with the increase of the pulse number and pressure level. Therefore the first pulse cycle is more effective than the following ones. By coupling moderate heating to high pressure, the lethality of the process increases but thermal degradation of the products can be detected. The optimization of the process condition thus results in a compromise between the reduction of the pressure value, due to the synergetic temperature action, and the achievement of quality of the final production. The juices processed under optimal processing conditions show a minimum shelf life of 21 d at a storage temperature of 4 °C. 相似文献
108.
Nicolle Dal’Acqua Ana Claudia Rangel Faria Mário César Vebber Hernane da Silva Barud Marcelo Giovanela Giovanna Machado Janaina da Silva Crespo 《International Journal of Hydrogen Energy》2018,43(33):15794-15806
The issues related to renewable energy sources is a matter of great worldwide appeal due to the increasing energy demand, instability in oil prices and environmental problems. In this context, the purpose of this study was to prepare self-assembled films of polyallylamine hydrochloride and poly (acrylic acid) supported onto bacterial cellulose membranes by a layer-by-layer approach with titanium dioxide (TiO2) nanoparticles and different concentrations of gold for application in hydrogen gas (H2) production by photocatalysis. The influence of the gold concentration and the presence and size of the gold nanoparticles (Au NPs), as well as the surface and thickness of the films on H2 production was investigated. The results showed that the film, prepared with a lower concentration of gold, presented the smallest Au NPs and, therefore, greater contact with the TiO2 nanoparticle surfaces, producing more H2. By analyzing the variation in all the experimental parameters used in the preparation of the films, it can be concluded that the best H2 production achieved was 29.12 μmol h?1 cm2. 相似文献
109.
Vallortigara Giorgio; Zanforlin Mario; Pasti Giovanna 《Canadian Metallurgical Quarterly》1990,104(3):248
Recent work has shown that in place-finding tasks rats rely on the geometric relations between the goal object and the shape of the environment. We tested young chickens (Gallus gallus domesticus) on similar tasks in a reference memory paradigm to determine whether differences exist between species in the ability to use geometric and nongeometric spatial information. The main findings were that chicks: (a) encoded and used both geometric and nongeometric (featural) information; (b) did not use the overall spatial arrangement of the features; (c) relied primarily on nongeometric cues when faced with contradictory information. Two mechanisms are evident in chicks' spatial representations: a metric frame for encoding the spatial arrangement of surfaces as surfaces and a cue-guidance system for encoding conspicuous landmarks near the target. The possibility of hierarchical organization and species differences in these two mechanisms are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Arnoldi A Resta D Brambilla F Boschin G D'Agostina A Sirtori E O'Kane F 《Molecular nutrition & food research》2007,51(4):431-436
Foods based on sweet lupin proteins are gaining attention from industry and consumers because of their possible role in the prevention of cardiovascular disease. When promoting lupin-based foods for inclusion in a daily diet, the thermal damage suffered during processing is of relevance to the bioactive and nutritional quality of the food product. N-(2-furoylmethyl)-L-lysine (furosine) quantification demonstrates that currently available sweet lupin protein isolates have a thermal damage comparable to or lower than other traditional food ingredients, and are a good source of lysine in non-dairy products. In lupin-based foods claiming to have cholesterol-lowering potential, shotgun proteomics offers itself as a fast and effective screening method for assessing the biological availability of active peptides. Such a method is readily applicable to other legume-enriched food products. 相似文献