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51.
The practice of architecture is very similar in different national settings despite what may be very different sociological and cultural origins of the profession, the attendant variances in how work is organized and distinctions in equality and gender roles. The aim of this paper is to examine the quest for equality in architecture for women in the UK and Spain reporting the findings of a comparative study into women architects’ careers in the two countries. Within the qualitative paradigm, semi-structured in-depth interviews were carried out with a total of 55 women architects in the UK and Spain. Findings indicate surprising differences in levels and terms of equality for women in the two countries and marked differences in women’s experiences of working as an architect. Women have come to the profession in Spain much later than their British counterparts and, somewhat surprisingly, are present in greater numbers. However, despite there being more of a ‘critical mass’ this has not served to improve their situation; they report much higher levels of discrimination and find it difficult to progress in their careers. Conclusions argue for a stronger approach by the professional bodies to help improve the position of women. 相似文献
52.
M.A. Peydro F. Parres R. Navarro S. Sanchez‐Caballero 《Polymer Engineering and Science》2014,54(6):1313-1324
This work studies the recovery of two grades of acrylonitrile–butadiene–styrene (ABS) contaminated with low‐density polyethylene (LDPE), by adding styrene–ethylene/butadiene–styrene (SEBS). To simulate contaminated ABS, virgin ABS was mixed with 1, 2, 4, and 8% of LDPE and then extruded at 220°C. After this, the ABS with the highest percentage of LDPE (8%) was mixed with 1, 2, 4, and 8% of SEBS and then extruded. Different blends were mechanically, rheologically, optically, and dimensionally characterized to study how different percentages of LDPE and SEBS modify their properties. The results obtained show how the tensile strength, Young modulus, elongation, and impact strength linearly decrease as the LDPE amount increases, for both natural and black ABS. Through the addition of SEBS to contaminated ABS, it is possible to improve its impact strength and elongation values nearly to those of virgin ABS. However, its tensile strength and Young modulus show no improvement, and even show a slight reduction. Regarding the rheological properties, the LDPE contamination in ABS causes a remarkable decrease in viscosity, and adding SEBS to the blend lowers its viscosity even further for both natural and black grades. This reduction is not a negative aspect, but rather quite the reverse, as the more fluid the material, the easier the mold injection process becomes. POLYM. ENG. SCI., 54:1313–1324, 2014. © 2013 Society of Plastics Engineers 相似文献
53.
Natalia Cullell Cristina Gallego-Fbrega Jara Crcel-Mrquez Elena Muio Laia Lluci-Carol Miquel Lleds Jesús M. Martín-Campos Jessica Molina Laura Casas Marta Almeria Israel Fernndez-Cadenas Jerzy Krupinski 《International journal of molecular sciences》2022,23(6)
Small vessel strokes (SVS) and intracerebral haemorrhages (ICH) are acute outcomes of cerebral small vessel disease (SVD). Genetic studies combining both phenotypes have identified three loci associated with both traits. However, the genetic cis-regulation at the protein level associated with SVD has not been studied before. We performed a proteome-wide association study (PWAS) using FUSION to integrate a genome-wide association study (GWAS) and brain proteomic data to discover the common mechanisms regulating both SVS and ICH. Dorsolateral prefrontal cortex (dPFC) brain proteomes from the ROS/MAP study (N = 376 subjects and 1443 proteins) and the summary statistics for the SVS GWAS from the MEGASTROKE study (N = 237,511) and multi-trait analysis of GWAS (MTAG)-ICH–SVS from Chung et al. (N = 240,269) were selected. We performed PWAS and then a co-localization analysis with COLOC. The significant and nominal results were validated using a replication dPFC proteome (N = 152). The replicated results (q-value < 0.05) were further investigated for the causality relationship using summary data-based Mendelian randomization (SMR). One protein (ICA1L) was significantly associated with SVS (z-score = −4.42 and p-value = 9.6 × 10−6) and non-lobar ICH (z-score = −4.8 and p-value = 1.58 × 10−6) in the discovery PWAS, with a high co-localization posterior probability of 4. In the validation PWAS, ICA1L remained significantly associated with both traits. The SMR results for ICA1L indicated a causal association of protein expression levels in the brain with SVS (p-value = 3.66 × 10−5) and non-lobar ICH (p-value = 1.81 × 10−5). Our results show that the association of ICA1L with SVS and non-lobar ICH is conditioned by the cis-regulation of its protein levels in the brain. 相似文献
54.
S.A. Macías-Sánchez R. Nava V. Hernández-Morales Y.J. Acosta-Silva L. Gómez-Herrera B. Pawelec S.M. Al-Zahrani R.M. Navarro J.L.G. Fierro 《International Journal of Hydrogen Energy》2012
A series of Cd1−xZnxS (x = 0.05–0.3) photocatalysts supported on ordered mesoporous silica (SBA-15) were prepared and investigated for hydrogen production from water splitting under visible light. Textural, structural and surface photocatalyst properties are determined by N2 adsorption isotherms, UV–vis, Raman and XPS and related to the activity results in hydrogen production. Raman and XRD results indicated a mutual interaction between Cd and Zn, forming nanoparticles of Cd1−xZnxS solid solutions. All Cd1−xZnxS/SBA-15 samples showed relatively high activities for hydrogen evolution. The hydrogen production rate is found to increase gradually when the zinc concentration on photocatalysts increases from 0.05 to 0.2, achieving a maximum for the photocatalyst with zinc concentration equal to 0.2. Variation in photoactivity is discussed in terms of modification in the conduction band and light absorption ability of Cd1−xZnxS particles derived from the changes in the Zn concentration in the Cd1−xZnxS solid solution. 相似文献
55.
Application of solar thermal desorption to remediation of mercury-contaminated soils 总被引:4,自引:0,他引:4
Solar thermal desorption at temperatures up to 500 °C is an innovative technology applied to the removal of mercury and arsenic from soil polluted by mining operations. As the soil is heated in a low and high-temperature solar system, the pollutant vapor pressure rises, producing mass transfer to the gas phase, which is then extracted by vacuum pumps and blower systems.In the UPC low-temperature experiments, removal of mercury from the polluted soil was as much as 76%. The experimental results show that volatilization of mercury is only significant when the temperature is above approximately 130 °C, which agrees with the predominant mercury solid phases detected. PSA middle-temperature experiments, showed that when soil and mine waste samples were heated to 400-500 °C, mercury elimination was significant (41.3-87%). However, the results from heating to 320 °C or below 300 °C, indicated little or negligible removal, possibly, because the fluid dynamics in the fluidized-bed module and the presence of cinnabar and pyrite rich-Hg as dominant mineral phases.These results show the potential for efficiently removing mercury and other pollutants from solid matrices (soil, waste, etc.) at low temperatures. 相似文献
56.
H. G. O. Becker R. Ebisch G. Israel G. Kroha W. Kroha O. Brede R. Mehnert 《Advanced Synthesis \u0026amp; Catalysis》1977,319(1):98-116
Kinetics and Mechanism of Aryldiazonium Salt Photolysis in Methanol. Determination of Absolute Rate Constants of Some Reaction Steps For benzene diazonium tetrafluoroborate and some p-substituted derivatives, the following values are determined:
- velocity constants for the photochemical electron transfer from pyrene and benzanthracene to aryl diazonium salts in acetonitrile solution (determination by quenching the donor fluorescence).
- velocity constants for electron transfer under the condition of pulse radiolysis in tert.-butanol-water solution;
- quantum yields and product composition (ArOMe, ArF and ArH, respectively) for the photolyses in methanol in the presence of varying concentrations of 2-methyl-2-nitroso-propane as a quencher of the thermal chain reaction.
57.
Study of the photon down‐conversion effect produced by thin silicon‐rich oxide films on silicon solar cells
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Israel Vivaldo Jesús Carrillo Osvaldo López Sandra Jiménez Jesús Martínez Dulce Murias José Alberto López 《国际能源研究杂志》2017,41(3):410-416
In the present work, we studied the photon down‐conversion effect produced by thin films of silicon oxide with embedded silicon nanocrystals also called silicon‐rich oxide (SRO). These films have been used to absorb high energy light and the re‐emission of two or more low energy photons (~1.1 eV) with the goal of improving the external quantum efficiency and consequently the conversion efficiency of silicon solar cells. According to our results, the incorporation of a thin SRO film on the solar cell surface increases the short circuit current and the FF of the silicon solar cells; the enhancement of spectral response is due to the high photoluminescence intensity of the SRO in the visible region when irradiated with UV light. An improvement of 38% in the solar cell efficiency has been observed in our particular solar cell fabrication process by the use of an SRO film with high photoluminescence intensity, which replaces the conventional silicon dioxide film. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
58.
Standard animal model programs can be modified to include the effect of a quantitative gene, even if only a fraction of the population is genotyped. Five methods to estimate the effect of a diallelic quantitative gene affecting a quantitative trait were compared to a standard animal model (model I) on simulated populations, based on mean squared errors and bias. In models II, III, and IV complete linkage between a single genetic marker and the quantitative trait gene was assumed. In models II and III the elements of the incidence matrix for the gene effect were 0 or 1 for genotyped individuals, and the probabilities of the possible candidate gene genotypes for individuals that were not genotyped. In model III segregation analysis was used to compute these probabilities. If only some of the cows were genotyped, the model III estimates were nearly unbiased, while model II underestimated the simulated effects. When only sires were genotyped, model II overestimated the simulated effect. In models V and VI two markers bracketing the quantitative gene with recombination frequencies of 0.1 and 0.2 with the quantitative gene were simulated, and the algorithm of Whittaker et al. (1996) was used to derive estimates of gene effect and location. In model V marker allele effects were included in the animal model analysis. In model VI, the model I genetic evaluations were analyzed. Model V estimates for both effect and location of the quantitative gene were unbiased, while model VI estimates were only 0.25 of the simulated effect. 相似文献
59.
Running with jointed legs poses a difficult control problem in robotics. Neural controllers are attractive because they allow the robot to adapt to changing environmental conditions. However, scalability is an issue with many neural controllers. This paper describes the development of a scalable neurofuzzy controller for the takeoff phase of the running stride. Scalability is achieved by selecting a controller whose size does not grow with the dimensionality of the problem. Empirical results show that with proper design the takeoff controller scales from a leg with a single movable link to one with three movable links without a corresponding growth in size and without a loss of accuracy. 相似文献
60.
Effect of misidentification on genetic gain and estimation of breeding value in dairy cattle populations 总被引:1,自引:0,他引:1
The effect of pedigree errors on estimated breeding value and genetic gain for a sex-limited trait with heritability of 0.25 was evaluated. Ten populations of 100,000 milking cows were simulated with correct paternity identification for all animals, and 10 populations were simulated with 10% incorrect paternal identification. The initial populations consisted of 100,000 unrelated individuals, and simulations were continued for 20 yr. The BLUP genetic evaluations were computed every year by an animal model analysis for each complete population. Estimated breeding values for the populations with 10% incorrect paternity were biased, especially in the later generations. Genetic gains were 4.3% higher with correct paternity identification. Reduction of pedigree errors by paternity confirmation of daughters of test sires by DNA microsatellites may result in considerable economic benefits, depending on the cost of testing in each country. 相似文献