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71.
This study breaks down carbon emissions into six effects within the 15 European Union countries group (EU-15) and analyses their evolution in four distinct periods: 1995–2000 (before European directive 2001/77/EC), 2001–2004 (after European directive 2001/77/EC and before Kyoto), 2005–2007 (after Kyoto implementation), and 2008–2010 (after Kyoto first stage), to determine which of them had more impact in the intensity of emissions. The complete decomposition technique was used to examine the carbon dioxide (CO2) emissions and its components: carbon intensity (CI effect); changes in fossil fuels consumption towards total energy consumption (EM effect); changes in energy intensity effect (EG effect); the average renewable capacity productivity (GC effect); the change in capacity of renewable energy per capita (CP effect); and the change in population (P effect). It is shown that in the post Kyoto period there is an even greater differential in the negative changes in CO2 emissions, which were caused by the negative contribution of the intensity variations of the effects EM, GC, CP and P that exceeded the positive changes occurred in CI and EG effects. It is also important to stress the fluctuations in CO2 variations before and after Kyoto, turning positive changes to negative changes, especially in France, Italy and Spain, revealing the presence of heterogeneity. Moreover, the positive effect of renewable capacity per capita and the negative effect of renewable capacity productivity are the main factors influencing the reduction in CO2 emissions during the Kyoto first stage. It is possible to infer from the results that one of the ways to reduce emissions intensity will be by increasing the renewable capacity and the productivity in energy generation and consequently through the reduction of the share of the consumption of fossil fuels. 相似文献
72.
Dietary supplements are a multi-billion dollar industry in the U.S., and their use is increasing exponentially. Additionally, many foods and beverages are increasingly being fortified with single or multiple vitamins and minerals. Consequently, nutrient intakes are exceeding the safe limits established by the Institute of Medicine. In this paper, we examine the benefits and drawbacks of vitamin and mineral supplements and increasing consumption of fortified foods (in addition to dietary intake) in the U.S. population. The pros and cons are illustrated using population estimates of folic acid, calcium, and vitamin D intake, highlighting concerns related to overconsumption of nutrients that should be addressed by regulatory agencies. 相似文献
73.
Mara Di Giulio Viviana di Giacomo Emanuela Di Campli Soraya Di Bartolomeo Susi Zara Guido Pasquantonio Amelia Cataldi Luigina Cellini 《Journal of materials science. Materials in medicine》2013,24(8):1977-1983
This study aimed to investigate the effect of saliva on Streptococcus mitis free cells and on S. mitis/human gingival fibroblasts (HGFs) co-culture model, in presence of 2-hydroxyethyl-methacrylate (HEMA). The bacterial aggregation both in the planktonic phase and on HGFs, as well as the apoptotic and necrotic eukaryotic cells amount were analyzed, in presence of saliva and/or HEMA. The aggregation test revealed a significant saliva aggregation effect on S. mitis strains compared to the untreated sample. No significant differences were recorded in the amount of culturable bacteria in all studied conditions; however, from microscopy images, the saliva/HEMA combining effect induced a significant bacterial aggregation and adhesion on HGFs. HEMA treatment decreased viable eukaryotic cell number with a parallel increment of necrotic cells, but when saliva was added to the co-culture, the viable cells percentage increased to a value comparable to the control sample. 相似文献
74.
Ümit Bayram Esra Öztürk Sezen Aksöz Necmettin Maraşlı 《Metallurgical and Materials Transactions A》2013,44(9):4051-4058
Thermal conductivity variations with temperature for solid phases in the Urea (U)–[X] mol pct 4-bromo-2-nitroaniline (BNA) system (X = 0, 2, 45, 89.9, and 100) were measured using the radial heat flow method. From graphs of thermal conductivity variations with temperature, the thermal conductivities of the solid phases at their melting temperature and temperature coefficients for the U–[X] mol pct BNA system (X = 0, 2, 45, 89.9, and 100) were found to be 0.26, 0.55, 0.46, 0.38, and 0.23 W/Km and 0.007781, 0.005552, 0.002058, 0.002188, and 0.002811 K?1, respectively. The ratios of thermal conductivity of the liquid phase to thermal conductivity of the solid phase in the U–[X] mol pct BNA system (X = 0, 2, 45, 89.9, and 100) were also measured to be 0.30, 0.44, 0.46, 0.49, and 0.51, respectively, with a Bridgman-type directional solidification apparatus at their melting temperature. 相似文献
75.
Ümit Bayram Alaaddin Özer Sezen Aksöz Necmettin Maraşlι 《Metallurgical and Materials Transactions A》2013,44(9):4042-4050
The grain boundary groove shapes for solid neopentylglycol solution (NPG-40 mol pct AMPD) in equilibrium with the neopentylglycol (NPG)–aminomethylpropanediol (AMPD) eutectic liquid (NPG-42.2 mol pct AMPD) have been directly observed using a horizontal linear temperature gradient apparatus. From the observed grain boundary groove shapes, the Gibbs–Thomson coefficient (Г) and solid–liquid interfacial energy (σ SL) of solid NPG solution have been determined to be (7.4 ± 0.7) × 10?8 K m and (6.4 ± 1.0) × 10?3 J m?2, respectively. The grain boundary energy of solid NPG solution has been determined to be (12.5 ± 1.0) × 10?3 J m?2 from the observed grain boundary groove shapes. The ratio of thermal conductivity of equilibrated eutectic liquid to thermal conductivity of solid NPG solution has also been determined to be 0.48. 相似文献
76.
Zhang Y Ronning F Gofryk K Mara NA Haberkorn N Zou G Wang H Lee JH Bauer E McCleskey TM Burell AK Civale L Zhu YT Jia Q 《Nanoscale》2012,4(7):2268-2271
Highly aligned carbon nanotube (CNT) ribbons were sandwiched in epitaxial superconducting NbC films by a chemical solution deposition method. The incorporation of aligned long CNTs into NbC film enhances the normal-state conductivity and improves the superconducting properties of the assembly. 相似文献
77.
78.
Feng Michelle C.; Courtney Christopher G.; Mather Mara; Dawson Michael E.; Davison Gerald C. 《Canadian Metallurgical Quarterly》2011,26(3):752
Previous studies reveal age by valence interactions in attention and memory, such that older adults focus relatively more on positive and relatively less on negative stimuli than younger adults. In the current study, eyeblink startle response was used to measure differences in emotional reactivity to images that were equally arousing to both age groups. Viewing positive and negative pictures from the International Affective Picture System had opposite effects on startle modulation for older and younger adults. Younger adults showed the typical startle blink pattern, with potentiated startle when viewing negative pictures compared to positive pictures. Older adults, on the other hand, showed the opposite pattern, with potentiated startle when viewing positive pictures compared to viewing negative and neutral pictures. Potential underlying mechanisms for this interaction are evaluated. This pattern suggests that, compared with younger adults, older adults are more likely to spontaneously suppress responses to negative stimuli and process positive stimuli more deeply. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
79.
Girls' math performance under stereotype threat: The moderating role of mothers' gender stereotypes.
Tomasetto Carlo; Alparone Francesca Romana; Cadinu Mara 《Canadian Metallurgical Quarterly》2011,47(4):943
Previous research on stereotype threat in children suggests that making gender identity salient disrupts girls' math performance at as early as 5 to 7 years of age. The present study (n = 124) tested the hypothesis that parents' endorsement of gender stereotypes about math moderates girls' susceptibility to stereotype threat. Results confirmed that stereotype threat impaired girls' performance on math tasks among students from kindergarten through 2nd grade. Moreover, mothers' but not fathers' endorsement of gender stereotypes about math moderated girls' vulnerability to stereotype threat: Performance of girls whose mothers strongly rejected the gender stereotype about math did not decrease under stereotype threat. These findings are important because they point to the role of mothers' beliefs in the development of girls' vulnerability to the negative effects of gender stereotypes about math. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
80.
The production of thermally concentrated fruit juices uses temperatures high enough to achieve at least a 5-log reduction of pathogenic bacteria that can occur in raw juice. However, the transportation and storage of concentrates at low temperatures prior to final packaging is a common practice in the juice industry and introduces a potential risk for postconcentration contamination with pathogenic bacteria. The present study was undertaken to evaluate the likelihood of Escherichia coli O157:H7, Listeria monocytogenes and Salmonella surviving in cranberry, lemon, and lime juice concentrates at or above temperatures commonly used for transportation or storage of these concentrates. This study demonstrates that cranberry, lemon, and lime juice concentrates possess intrinsic antimicrobial properties that will eliminate these bacterial pathogens in the event of postconcentration recontamination. Bacterial inactivation was demonstrated under all conditions; at least 5-log Salmonella inactivation was consistently demonstrated at -23 degrees C (-10 degrees F), at least 5-log E. coli O157:H7 inactivation was consistently demonstrated at -11 degrees C (12 degrees F), and at least 5-log L. monocytogenes inactivation was consistently demonstrated at 0 degrees C (32 degrees F). 相似文献