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71.
In this study, the quality characteristics, i.e., the acidity and acylglycerols, of currently produced Mallorcan oil was analyzed by titration and gas-chromatographic technique, respectively, in approximately 400 samples of monovarietal olive oil made from three genetic varieties (Arbequina, Empeltre, and Picual) on the island of Mallorca during the 2003/2004 and 2005/2006 seasons, and the differences in the compositions were discussed. Composition analysis showed that free fatty acids (FFAs) and DAGs were produced mainly by hydrolysis of triacylglycerols (TAGs). Fruit storage tests revealed that hydrolysis occurred during storage of olive fruits. The DAG content was higher in oil with higher acidity, but the maximal DAG content was only about 10 with 30% acidity, and the primary isomer found in Mallorcan oil was 1,3-DAG. However, the chiral-chromatographic study on the ratio of sn-1,2-DAG to the sum of sn-1,2-DAG and sn-2,3-DAG in a slightly hydrolyzed oil sample indicated that Empeltre and Picual fruits possess an sn-3-enantioselective lipase that leads to accumulation of sn-1,2-DAG. In currently produced Mallorcan oil, significant isomerization appears to occur and hydrolysis of the resulting 1,3-DAGs seems to lessen DAG accumulation.  相似文献   
72.
Background: The incidence of fungal infections, especially those caused by Candida yeasts, has increased over the last two decades. However, the indicated therapy for fungal control has limitations. Hence, medicinal plants have emerged as an alternative in the search for new antifungal agents as they present compounds, such as essential oils, with important biological effects. Published data demonstrate important pharmacological properties of the essential oil of Cymbopogon nardus (L.) Rendle; these include anti-tumor, anti-nociceptive, and antibacterial activities, and so an investigation of this compound against pathogenic fungi is interesting. Objective: The aim of this study was to evaluate the chemical composition and biological potential of essential oil (EO) obtained from the leaves of C. nardus focusing on its antifungal profile against Candida species. Methods: The EO was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). Testing of the antifungal potential against standard and clinical strains was performed by determining the minimal inhibitory concentration (MIC), time-kill, inhibition of Candida albicans hyphae growth, and inhibition of mature biofilms. Additionally, the cytotoxicity was investigated by the IC50 against HepG-2 (hepatic) and MRC-5 (fibroblast) cell lines. Results: According to the chemical analysis, the main compounds of the EO were the oxygen-containing monoterpenes: citronellal, geranial, geraniol, citronellol, and neral. The results showed important antifungal potential for all strains tested with MIC values ranging from 250 to 1000 μg/mL, except for two clinical isolates of C. tropicalis (MIC > 1000 μg/mL). The time-kill assay showed that the EO inhibited the growth of the yeast and inhibited hyphal formation of C. albicans strains at concentrations ranging from 15.8 to 1000 μg/mL. Inhibition of mature biofilms of strains of C. albicans, C. krusei and C. parapsilosis occurred at a concentration of 10× MIC. The values of the IC50 for the EO were 96.6 μg/mL (HepG-2) and 33.1 μg/mL (MRC-5). Conclusion: As a major virulence mechanism is attributed to these types of infections, the EO is a promising compound to inhibit Candida species, especially considering its action against biofilm.  相似文献   
73.
Habitation: A Domain-Specific Language for Home Automation   总被引:1,自引:0,他引:1  
Developers need suitable tools to develop home automation systems while enhancing quality and productivity. One solution is to use domain-specific languages (DSLs) within a model-driven approach. The Habitation DSL provides a powerful visual development environment, including a catalog of reusable functional units and a set of home automation interconnection primitives. The model-driven approach offers mechanisms to automatically generate code to enhance the quality and portability of home automation systems. The result is an Eclipse-based tool whose usability the authors have validated in a case study.  相似文献   
74.
A 55-year-old man presented with the suspicion of pulmonary tuberculosis. He was treated with isoniazid, ethambutol, rifampicin and pyrazinamide. However, he developed high fever, skin rash and pulmonary infiltrates following 10 days of treatment. The above-mentioned conditions subsided promptly after stopping ethambutol therapy and reappeared after rechallenge, marking ethambutol as the offender. To present knowledge, this is the second case of an ethambutol-induced hypersensitivity lung reaction reported in English literature.  相似文献   
75.
Immiscible flow governs the macroscopic behavior of aqueous and non-aqueous phase liquids inside the porous media. Ganglia generation and movement of the advancing front during fluid displacement can only be described by means of microscopic models. In this study, a pore network cellular automata is used to simulate the displacement of a nonaqueous phase liquid by water inside a porous media. Pore sizes are generated using random and stochastic fields. The numerical model captures the evolution of interfaces and fluid movement for each pressure applied to the displacing fluid. Observed trends suggest that ganglia size and shape, and fingering are directly related to anisotropy, pore size spatial variability and correlation length. The results show that micro- and mesoscale porous media properties control the nonaqueous phase residual saturation and observed macoscopic behavior.  相似文献   
76.
The occurrence of the polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) was studied in four different bivalve species (mussels, oysters, carpetshells, and cupped oysters) collected in three different sampling stations at the Spanish Coast from 1994 onward. The analysis revealed an unexpected isomer distribution of chlorosubstituted dioxins and furans characterized by a complex mixture of TCDF and TCDD, including both toxic and nontoxic isomers and highly chlorinated congeners, mainly OCDD. Principal component analysis revealed similarities between identical species collected from the different sites. A dioxin fingerprint could be easily distinguished between bivalve species collected in the same sampling point. The dioxin fingerprint found in filter-feeders was also compared to other marine species showing remarkable differences. Due to the habits of the bivalve species, sediment samples were also analyzed within this study. No similarities in the pattern were found for both matrices, the sediments and the bivalves. In the absence of a potential source of these toxicants affecting these species the hypothesis of a specific metabolism of the bivalves is suggested. No values higher than 4 pg WHO-TEQ/g whole weight were determined, and all samples met the current limit proposed by European Regulations. Independently of the bivalve species considered, the major contribution to the total WHO-TEQ comes from 2,3,7,8-TCDF and 2,3,4,7,8-PeCDF, at about the same levels of the 2,3,7,8-TCDD and 1,2,3,7,8-PCDD.  相似文献   
77.
We designed and developed a vision-based computer interface which works with head movements. The system was implemented in a centre for users with cerebral palsy and they used it in contexts related with recreation or with education. During this process, it was observed that the continued use of the interface with a set of training tasks may act as a physical and cognitive rehabilitation tool and complement users’ rehabilitation therapy. We comment on five case studies of users who have worked with the interface for five months and whose qualitative outcomes, observed by the therapists who accompanied them, were positive; specifically there was improvement in work posture, head control, increased endurance, decreased involuntary movements and improved spatial orientation. The case studies also showed the need to supervise the users’ work in order to achieve these aims, along with the importance of motivation and active, voluntary participation of users in the rehabilitation process.  相似文献   
78.
79.
A total of 16 543 artificial ponds were inventoried. Ninety‐one per cent of the ponds were classified as for farming use. Generally, the fraction of farm land converted to pond structures was close to that predicted from the average annual precipitation in the region. However, in several areas, this fraction was remarkably higher than the value predicted, probably due to excessive groundwater extraction. Overall, the naturalisation stage of ponds was poor. However, ponds sited on natural substrate basins had more structured‐marginal vegetation, compared with ponds of artificial substrate basins. Furthermore, other factors related to pond management might seriously limit their naturalisation stage. Despite the high abundance of ponds in Andalusia, our results suggest that, in order to improve the potential for biodiversity conservation in these environments, substantial structural and management changes are required.  相似文献   
80.
The effect of chemical composition and processing parameters on the formation of acicular ferrite and/or bainite has been investigated.In particular,this paper deals with the influence that N through its combination with V,as V(C,N) precipitates,has on the decomposition of austenite.Likewise,the intragranular nucleation potency of V(C,N) precipitates is analyzed through the continuous cooling transformation diagrams (CCT) of two C-Mn-V steels with different contents of N.Results reported in this work allow us to conclude that acicular ferrite can only be achieved alloying with vanadium and nitrogen,meanwhile bainite is promoted in steels with a low level of nitrogen.It is concluded that higher strength values are obtained in acicular ferrite than in bainitic steel but a similar brittle-ductile transition temperature (BDT),and lower values of impact absorbed energy (KV) has been recorded in nitrogen-rich steel.  相似文献   
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