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排序方式: 共有6120条查询结果,搜索用时 15 毫秒
931.
Tâmmila Venzke Klug Elena Collado Ascensión Martínez-Sánchez Perla A. Gómez Encarna Aguayo Mariano Otón Francisco Artés Francisco Artés-Hernandez 《Food and Bioprocess Technology》2018,11(3):561-571
Nowadays, consumers demand healthy, safe, and ready-to-eat horticultural products because of their lifestyle. In this regard, new legume-based food product development with eco-innovative technologies seems to be an interesting market. The effect on quality of an innovative pesto sauce, made of fresh faba bean seeds, of an alternative continuous microwave treatment pasteurization (MW, 11 kW; 30 s) regarding a conventional pasteurization (85 °C; 5 min) throughout 20 days at 5 °C was studied. Non-heated blended samples were used as control. The microbial quality was satisfactory in all treatments. MW treatment improved the sensorial quality of pesto sauce and decreased condensed tannins. Additionally, MW-treated samples showed the best texture, consistency, and color, preserving its chlorophyll and carotenoid content. On the other hand, thermal treatments showed a decrease in total phenolic compounds (TPC) and antioxidant capacity (TEAC) after heating, regarding control samples; however, TPC and TEAC remained quite constant throughout the storage. 相似文献
932.
Marianela Hazel Álvarez-Hernández Francisco Artés-Hernández Felipe Ávalos-Belmontes Marco Antonio Castillo-Campohermoso Juan Carlos Contreras-Esquivel Janeth Margarita Ventura-Sobrevilla Ginés Benito Martínez-Hernández 《Food and Bioprocess Technology》2018,11(3):511-525
Fruit and vegetables are much appreciated by consumers due to their nutritional values and health-promoting compounds. However, different factors affect the postharvest life of such products, in where ethylene is a major one, even at low concentrations, besides temperature and relative humidity. Therefore, high attention has been focused on the development of effective tools to remove ethylene from the atmosphere surrounding these products during storage or in transit. Potassium permanganate scrubbers are one of the most used technologies to remove ethylene from horticultural products. To facilitate and improve the oxidation process, potassium permanganate has been supported onto inert solid materials of a small particle size. In this review, we aim to provide an outline of the most common materials used as potassium permanganate supports on postharvest treatment and their respective effects on quality aspects of various fresh produce during postharvest life. Vermiculite, activated alumina, zeolite, silica gel, activated carbon and clays are the most popular materials that have been used as a support of potassium permanganate-based ethylene scrubbers. The literature suggests that potassium permanganate supported onto silica gel or zeolite seems to be a promising tool to maintain fruit and vegetables quality attributes for long-term storage. Although vermiculite and activated alumina are the most commonly used materials to reach this goal, not promising results have been reported. 相似文献
933.
Marta Tortajada Pedro Vicente Martínez-Culebras Verónica Navarro Honorato Monzó Daniel Ramón 《European Food Research and Technology》2009,230(1):79-87
Direct and sensitive PCR detection of contaminant microflora in cocoa extracts is affected by the quality of the template
DNA. This study compares the efficacy of five different commercial DNA extraction methods, selective enrichment broths and
use of glycolitic enzymes to obtain quality DNA for PCR detection of both fungi and bacteria in artificially inoculated cocoa
extract samples. PCR-based methods were applied to detect contaminant microflora in cocoa extracts using as model organisms:
Aspergillus nidulans, Bacillus subtilis, Escherichia coli and Salmonella enterica. The quality of the extracted DNA was assessed in terms of PCR inhibitor content with results indicating that the HighPure
PCR template (Roche) kit was the best methodology under the conditions assayed. PCR protocols using this commercial kit and
a combination of glycolitic enzymes and enrichment procedures gave a detection limit of 100 conidia/g and 100 cfu/g for filamentous
fungi and bacteria, respectively. The selected extraction and PCR procedures were also tested to assess their suitability
for detecting filamentous fungi and bacteria on an industrial scale. They were sensitive enough to detect fungal and bacterial
contaminants within the legally required limits. The results obtained with the molecular approach were in agreement with those
of standard microbiological tests but require a considerably shorter analysis time. Thus, the molecular approach provides
a sensitive and rapid alternative to check for microbial contamination in cocoa extracts. 相似文献
934.
Ferré-Huguet N Nadal M Schuhmacher M Domingo JL 《Environmental science & technology》2006,40(1):61-66
The purpose of this study was to assess the environmental impact of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of a new hazardous waste incinerator (HWI) 4 years after regular operation of the facility. A double approach was carried out. The PCDD/F congener profiles corresponding to environmental samples, soil and herbage, collected before the HWI (baseline) and 4 years after starting regular operations, as well as PCDD/F profiles of air emission samples, were compared. The potential health risks (carcinogenic and noncarcinogenic) due to PCDD/F exposure were assessed for adults and children living in the neighborhood of the facility. Human exposure to PCDD/Fs was mainly due to dietary food intake. Comparisons between the PCDD/F congener profiles corresponding to the baseline and current surveys, as well as data concerning the human health risk assessment, indicate that the HWI in question does not cause additional risks to the environment orto the population living in the vicinity of the facility. 相似文献
935.
Casaseca-de-la-Higuera P Martín-Fernández M Alberola-López C 《IEEE transactions on bio-medical engineering》2006,53(7):1330-1345
Practitioners' decision for mechanical aid discontinuation is a challenging task that involves a complete knowledge of a great number of clinical parameters, as well as its evolution in time. Recently, an increasing interest on respiratory pattern variability as an extubation readiness indicator has appeared. Reliable assessment of this variability involves a set of signal processing and pattern recognition techniques. This paper presents a suitability analysis of different methods used for breathing pattern complexity assessment. The contribution of this analysis is threefold: 1) to serve as a review of the state of the art on the so-called weaning problem from a signal processing point of view; 2) to provide insight into the applied processing techniques and how they fit into the problem; 3) to propose additional methods and further processing in order to improve breathing pattern regularity assessment and weaning readiness decision. Results on experimental data show that sample entropy outperforms other complexity assessment methods and that multidimensional classification does improve weaning prediction. However, the obtained performance may be objectionable for real clinical practice, a fact that paves the way for a multimodal signal processing framework, including additional high-quality signals and more reliable statistical methods. 相似文献
936.
Martínez Santiesteban FM Swanson SD Noll DC Anderson DJ 《IEEE transactions on bio-medical engineering》2006,53(3):547-558
Magnetic resonance (MR) compatibility of biomedical implants and devices represents a challenge for designers and potential risks for users. This paper addresses these problems and presents the first MR-compatible multichannel silicon chronic microelectrode system, used for recording and electrical stimulation of the central nervous system for animal models. A standard chronic assembly, from the Center for Neural Communication Technology at the University of Michigan, was tested on a 2 Tesla magnet to detect forces, heating, and image distortions, and modified to minimize or eliminate susceptibility artifacts, tissue damage, and electrode displacement, maintaining good image quality and safety to the animals. Multiple commercial connectors were tested for MR compatibility and several options for the reference electrode were also tested to minimize image artifacts and provide a stable biocompatible reference for shortand long-term neural recordings. Different holding screws were tested to anchor the microelectrode assembly on the top of the skull. The final selection of this part was based on MR-compatibility, biocompatibility, durability, and mechanical and chemical stability. The required adaptor to interconnect the MR-compatible microelectrode with standard data acquisition systems was also designed and fabricated. The final design is fully MR-compatible and has been successfully tested on guinea pigs. 相似文献
937.
938.
939.
Coagulation and electrocoagulation of wastes polluted with dyes 总被引:1,自引:0,他引:1
Cañizares P Martínez F Jiménez C Lobato J Rodrigo MA 《Environmental science & technology》2006,40(20):6418-6424
Dyes are common pollutants in a large variety of industrial wastewaters, and the treatment of these wastes by coagulation has been extensively studied in the literature. This work is focused on the comparison of the efficiencies of the chemical and the electrochemical coagulation processes with hydrolyzing aluminum salts, and it tries to determine the similarities or differences that exist between the two coagulation processes. To do this, Eriochrome Black T solutions were used as a model of dye-polluted wastewater, and experiments of both coagulation technologies were planned to meet the same operation conditions. The pH, the aluminum concentration, the type of electrolyte, and the mode of dosing of aluminum were found to influence the process. Moreover, the speciation of aluminum was found to be the key parameter to explain the results, in terms of the mechanisms previously proposed in the literature for dissolved organic matter coagulation. 相似文献
940.
Domínguez M Alvarez R Pérez M Palczewski K de Lera AR 《Chembiochem : a European journal of chemical biology》2006,7(11):1815-1825
Artificial visual pigment formation from ring-demethylated retinals was studied in an effort to understand the effect that methyl groups on the chromophore cyclohexenyl ring have on the visual cycle. The stereoselective synthesis of the 11-cis-ring-demethylated analogues involves thallium-accelerated Suzuki cross-coupling reactions and highly stereocontrolled Wittig reactions to form key bonds. Only 11-cis-1,1,5-trisdemethylretinal (2) failed to form an artificial pigment, whilst variable pigment-formation yields were determined for the remaining analogues, increasing with the number (and location) of the chromophore hydrophobic ring methyl groups. Our results with the monodemethylated analogues 11-cis-5-demethylretinal (4) and 11-cis-1-demethylretinal (5) show that the C1-2-CH(3) groups are more important for pigment formation than the C5-CH(3) substituent. This is reflected in the absorption maxima of the artificial pigments, with values closer to that of native rhodopsin for 4. Docking studies based on a rhodopsin crystal structure, however, predict a lower pigment stability for 4 than for 5. Gas-phase DFT (B3LYP/6-31G*) computations of the free-ligand geometries, conformational searches about the C6--C7 bond, and docking studies revealed that, although the conformation of bound 5 is close to that of the native chromophore, the ligand needs to overcome the energy cost of shifting the unbound favored 6-s-trans conformation to the bound 6-s-cis form. In addition, the presence of an extra methyl group at C18 (11-cis-18-methylretinal, 7) is tolerated well and adds further stability to the complex, most probably due to increased hydrophobic interactions. 相似文献