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61.
José Juan Escobar-Chávez David Quintanar-Guerrero Adriana Ganem-Quintanar 《Drug development and industrial pharmacy》2013,39(4-5):447-454
The objective of this study was to determine the penetration of sodium naproxen, formulated in Pluronic F-127 (PF-127) gels containing Azone® and Transcutol® as penetration enhancers, through human skin in vivo. It was found that the combination of Azone® and Transcutol® in PF-127 gels enhanced sodium naproxen penetration, with enhancement ratios of up to two fold compared with the formulation containing only Transcutol®. These results were confirmed by TEWL and ATR-FTIR spectroscopy, suggesting a synergic action for Azone® and Transcutol®. Because of the thermo-reversible behavior of Pluronic gels, the influence of the components added to the gel formulations on viscosity, as a function of temperature, was also studied. 相似文献
62.
Giancarlo Paganin Adriana Angelotti Chiara Ducoli Monica Lavagna Cinzia Talamo Stefano Luccietto 《Energy Efficiency》2017,10(6):1343-1364
Nowadays, the focus on the building energy consumption in the use phase prevails over an interest concerning the energy impacts linked to all the other phases of the construction process. However, reducing operational energy could lead to shifting the impacts from one stage to another. Thus, combining the study of strategies improving energy efficiency in the use phase with a life cycle approach is crucial. Exhibition halls are peculiar buildings from the geometry, construction and use points of view, rarely addressed in energy and life cycle energy analysis studies. Therefore, in this paper, a representative hall of the Milan Trade Fair is taken as a case study. A building energy simulation model is firstly calibrated in order to derive the operational energy for climatisation. The operational energy appears artificially low due to the short use period during the year. When compared with the calculated embodied energy of the envelope and structure, it is found that 57 years would be needed to balance energy spent in the construction and in the use phase. Further, some retrofit interventions are proposed and analyzed. Insulation interventions are not attractive from the economic payback time point of view. However, when the embodied energy of the retrofit interventions is compared with the energy savings in the use phase, interesting energy payback times are obtained. Therefore, this study puts in evidence on the importance of adopting a life cycle perspective, especially for buildings with low-intensity use. Eventually, the critical issues of the life cycle energy analysis are deeply discussed. 相似文献
63.
Adriana Dapena José A. García-Naya Paula M. Castro Vicente Zarzoso 《Circuits, Systems, and Signal Processing》2014,33(8):2605-2623
In current digital communication systems, channel information is typically acquired by supervised approaches that use pilot symbols included in the transmit frames. Given that pilot symbols do not convey user data, they penalize throughput spectral efficiency, and transmit energy consumption of the system. Unsupervised channel estimation algorithms could be used to mitigate the aforementioned drawbacks although they present higher computational complexity than that offered by supervised ones. This paper proposes a simple decision method suitable for slowly varying channels to determine whether the channel has suffered a significant variation, which requires to estimate the matrix of the recently changed channel. Otherwise, a previous estimate is used to recover the transmitted symbols. The main advantage of this method is that the decision criterion is only based on information acquired during the time frame synchronization, which is carried out at the receiver. We show that the proposed criterion provides a considerable improvement of computational complexity for both supervised and unsupervised methods, without incurring in a penalization in terms of symbol error ratio. Specifically, we consider systems that make use of the popular Alamouti code. Performance evaluation is accomplished by means of simulated channels as well as making use of indoor wireless channels measured using a testbed. 相似文献
64.
Codruta Soica Corina Danciu Germaine Savoiu-Balint Florin Borcan Rita Ambrus Istvan Zupko Florina Bojin Dorina Coricovac Sorina Ciurlea Stefana Avram Cristina Adriana Dehelean Teodora Olariu Petru Matusz 《International journal of molecular sciences》2014,15(5):8235-8255
Betulinic acid, a very promising anti-melanoma agent, has very low water solubility that causes low bioavailability. To overcome this inconvenience, a highly water-soluble cyclodextrin was used (octakis-[6-deoxy-6-(2-sulfanyl ethanesulfonic acid)]-γ-cyclodextrin). The complex was physico-chemically analyzed using differential scanning calorimetry (DSC), X-ray and scanning electron microscopy (SEM) methods and then in vitro tested for its antiproliferative activity by the MTT assay and by cell cycle analysis. Finally, the complex was tested in vivo using an animal model of murine melanoma developed in C57BL/6J mice, where it caused a reduction in tumor volume and weight. The study revealed the beneficial influence of betulinic acid inclusion into the cyclodextrin in terms of antiproliferative activity and in vivo tumor development. 相似文献
65.
66.
P.L.J. Monteiro Jr. E.S. Ribeiro R.P. Maciel A.L.G. Dias E. Solé Jr. F.S. Lima R.S. Bisinotto W.W. Thatcher R. Sartori J.E.P. Santos 《Journal of dairy science》2014
The objectives of the current study were to evaluate the effects of supplemental progesterone after artificial insemination (AI) on expression of IFN-stimulated genes (ISG) in blood leukocytes and fertility in lactating dairy cows. Weekly cohorts of Holstein cows were blocked by parity (575 primiparous and 923 multiparous) and method of insemination (timed AI or AI on estrus) and allocated randomly within each block to untreated controls, a controlled internal drug release (CIDR) containing 1.38 g of progesterone from d 4 to 18 after AI (CIDR4), or a CIDR on d 4 and another on d 7 after AI and both removed on d 18 (CIDR4+7). Blood was sampled to quantify progesterone concentrations in plasma and mRNA expression in leukocytes for the ubiquitin-like IFN-stimulated gene 15-kDa protein (ISG15) and receptor transporter protein-4 (RTP4) genes. Pregnancy was diagnosed on d 34 ± 3 and 62 ± 3 after AI. Treatment increased progesterone concentrations between d 5 and 18 after AI in a dose-dependent manner (control = 3.42, CIDR4 = 4.97, and CIDR4+7 = 5.46 ng/mL). Cows supplemented with progesterone tended to have increased luteolysis by d 19 after AI (control = 17.2; CIDR4 = 29.1; CIDR4+7 = 30.2%), which resulted in a shorter AI interval for those reinseminated after study d 18. Pregnancy upregulated expression of ISG in leukocytes on d 19 of gestation, but supplementing progesterone did not increase mRNA abundance for ISG15 and RTP4 on d 16 after insemination and tended to reduce mRNA expression on d 19 after AI. For RTP4 on d 19, the negative effect of supplemental progesterone was observed only in the nonpregnant cows. No overall effect of treatment was observed on pregnancy per AI on d 62 after insemination and averaged 28.6, 32.7, and 29.5% for control, CIDR4, and CIDR4+7, respectively. Interestingly, an interaction between level of supplemental progesterone and method of AI was observed for pregnancy per AI. For cows receiving exogenous progesterone, the lower supplementation with CIDR4 increased pregnancy per AI on d 62 in cows inseminated following timed AI (CIDR4 = 39.2; CIDR4+7 = 27.5%); in those inseminated following detection of estrus, however, the use of a second insert on d 7 resulted in greater pregnancy per AI (CIDR4 = 26.9; CIDR4+7 = 31.5%). Pregnancy loss did not differ among treatments. Supplemental progesterone post-AI using a single intravaginal insert on d 4 was beneficial to pregnancy in cows inseminated following timed AI, but incremental progesterone with a second insert on d 7 did not improve fertility of dairy cows. 相似文献
67.
Renan C. Chisté Marisa Freitas Adriana Z. Mercadante Eduarda Fernandes 《Journal of food science》2014,79(9):H1841-H1847
β‐Carotene, zeaxanthin, lutein, β‐cryptoxanthin, and lycopene are liposoluble pigments widely distributed in vegetables and fruits and, after ingestion, these compounds are usually detected in human blood plasma. In this study, we evaluated their potential to inhibit hemolysis of human erythrocytes, as mediated by the toxicity of peroxyl radicals (ROO?). Thus, 2,2′‐azobis (2‐methylpropionamidine) dihydrochloride (AAPH) was used as ROO? generator and the hemolysis assay was carried out in experimental conditions optimized by response surface methodology, and successfully adapted to microplate assay. The optimized conditions were verified at 30 × 106 cells/mL, 17 mM of AAPH for 3 h, at which 48 ± 5% of hemolysis was achieved in freshly isolated erythrocytes. Among the tested carotenoids, lycopene (IC50 = 0.24 ± 0.05 μM) was the most efficient to prevent the hemolysis, followed by β‐carotene (0.32 ± 0.02 μM), lutein (0.38 ± 0.02 μM), and zeaxanthin (0.43 ± 0.02 μM). These carotenoids were at least 5 times more effective than quercetin, trolox, and ascorbic acid (positive controls). β‐Cryptoxanthin did not present any erythroprotective effect, but rather induced a hemolytic effect at the highest tested concentration (3 μM). These results suggest that selected carotenoids may have potential to act as important erythroprotective agents by preventing ROO?‐induced toxicity in human erythrocytes. 相似文献
68.
Characterization of a water-based paint for corrosion protection 总被引:1,自引:0,他引:1
Paula Dias Catarina Carneiro Luísa Andrade José Sousa João Machado Adélio Mendes 《Journal of Coatings Technology and Research》2012,9(3):365-374
Corrosion of steel rebars in reinforced concrete is one of the major problems in the construction industry. Carbonation reactions
of concrete with carbon dioxide and, mainly, the chloride salts action are the main causes responsible for concrete degradation.
Protective coatings help to improve the durability of concrete structures by acting as a physical barrier against the corrosion
agents. Waterborne paints are usually used for concrete protection rather than solvent-based paints since they are less pollutant.
The aim of this work is to investigate the influence of the pore size and porosity on the permeability of the paints films
toward sodium chloride. Three characterization methods from membrane science were implemented to characterize paint coatings.
The time-lag method was used to determine the permeability toward the sodium chloride and toward helium and argon, these for
approximately 100% relative humidity. From the seven waterborne paints formulated, only one was found to be suitable for surface
protection of reinforced concrete, since its permeability toward NaCl was smaller than 10−14 m2 s−1, the threshold value required by National Laboratory of Civil Engineering (LNEC) in Portugal. For the formulated paints,
it was observed that the average pore size correlates well with the permeability toward sodium chloride. This is an important
result since obtaining the permeability toward sodium chloride of corrosion protective paints is very time consuming, while
the average pore size can be obtained in a much shorter time. 相似文献
69.
Edible coatings enriched with essential oils for extending the shelf‐life of ‘Bravo de Esmolfe’ fresh‐cut apples 下载免费PDF全文
Adriana C. Guerreiro Custódia M. L. Gago Maria L. Faleiro Maria G. C. Miguel Maria D. C. Antunes 《International Journal of Food Science & Technology》2016,51(1):87-95
Edible coatings based on sodium alginate (AL) and pectin (PE) at 1% and 2%(w/v) enriched with eugenol (Eug) and citral (Cit) at minimum inhibitory concentrations (MIC) (0.10% and 0.15%) and double MIC were used to preserve the quality of fresh‐cut apples ‘Bravo de Esmolfe’. Samples were taken, through 14 day at 4 °C, for analysis of colour CIE(L*h°C*), firmness, °Brix, weight loss, antioxidant activity (TEAC), microbial growth and taste panels. With those quality characteristics, three groups were formed by the principal component and hierarchical cluster analysis, for each coating base (AL or PE). Based on, for each quality parameter measured, the mean closest value to the one at harvest for colour, higher value for firmness, °Brix and TEAC, and lower value for weight loss and microbial spoilage, the best group was selected for AL and PE. From each group, two edible coatings with the highest scores in overall acceptability were selected for fresh‐cut apples: AL2% + Eug 0.1%, AL2% + Cit 0.15% + Eug 0.1%, PE 2% + Cit 0.15% and PE 2% + Eug 0.2%. 相似文献
70.