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Low-cost water-based P25-TiO 2 pastes were formulated and used to produce porous TiO 2 films in application to the fabrication of dye-sensitized solar cells. The structural properties of the films were characterized using a variety of techniques such as stylus profilometry, FEG-SEM imaging, BET surface area, and BJH pore size analyses. These were compared to films produced from a commercial paste, DSL 18 NR-AO (Dyesol). The major difference was in the fraction of macroporosity: 23% of the total pore volume for films produced with the commercial material and 67–73% for the P25-TiO 2 films owing to the vast difference in dispersion and size distribution of the particles in the two types of pastes. The macroporosity was found to have a dramatic effect on the dye diffusion kinetics measured using in situ UV-Vis reflectance spectroscopy. The sensitization of P25-based films was much faster for heavily macroporous P25-TiO 2 films (>90% saturation at 15–35 mins) than for their commercial analogue (>90% saturation at 110 mins). DSC devices built with optimized P25-TiO 2 photoanodes showed better performance at short dye immersion time (30 mins and 1 hr) due to faster percolation of the dye molecules through the film.

Low-cost water-based P25-TiO2 pastes were formulated and used to produce porous TiO2 films in application to the fabrication of dye-sensitized solar cells. The structural properties of the films were characterized using a variety of techniques such as stylus profilometry, FEG-SEM imaging, BET surface area, and BJH pore size analyses. These were compared to films produced from a commercial paste, DSL 18 NR-AO (Dyesol). The major difference was in the fraction of macroporosity: 23% of the total pore volume for films produced with the commercial material and 67–73% for the P25-TiO2 films owing to the vast difference in dispersion and size distribution of the particles in the two types of pastes. The macroporosity was found to have a dramatic effect on the dye diffusion kinetics measured using in situ UV-Vis reflectance spectroscopy. The sensitization of P25-based films was much faster for heavily macroporous P25-TiO2 films (>90% saturation at 15–35 mins) than for their commercial analogue (>90% saturation at 110 mins). DSC devices built with optimized P25-TiO2 photoanodes showed better performance at short dye immersion time (30 mins and 1 hr) due to faster percolation of the dye molecules through the film.

Seamounts provide oases of hard substrate in the deep sea that are frequently associated with locally enhanced biological productivity and diversity. There is now increasing recognition of their ecological and socio-economic importance. However, management strategies for these habitats are constrained not only by limited ecological understanding but by the general public’s understanding of the pressures facing these ecosystems. This study adds to the growing literature on willingness to pay for conservation of deep-sea ecosystems and species by undertaking a stated preference survey to assess tourist’s awareness of seamounts and their preferences for protection within the Galapagos Marine Reserve. Visitors’ perceptions of seamount biodiversity must be studied because tourists are key drivers of the Galapagos economy and account for 41% of the Marine Reserve budget. Our survey captured the attitudes, perceptions and willingness to pay of tourists for an increase in the entrance fee to the Galapagos Marine Reserve. Results showed tourists were willing to pay on average US$48.93 in addition to existing entrance fees. The results of this study support the willingness to develop a multiuse management plan for the Galapagos Marine Reserve, balancing conservation, local communities livelihoods and sustainable tourism. Our results evidence a willingness to support and fund conservation, which is of critical importance to both the Galapagos National Park and local non-governmental organizations heavily reliant for their work on entrance fees and donations respectively. Overall, the conclusion from this study is that, despite limited knowledge, visitors of the Galapagos Islands attach positive and significant values to the conservation of seamount biodiversity.

Objectives: To assess the relative cost-effectiveness of laparoscopic methods of inguinal hernia repair compared with open flat mesh and open non-mesh repair. Methods: Data on the effectiveness of these alternatives came from three systematic reviews comparing: (i) laparoscopic methods with open flat mesh or non-mesh methods; (ii) open flat mesh with open non-mesh repair; and (iii) methods that used synthetic mesh to repair the hernia defect with those that did not. Data on costs were obtained from the authors of economic evaluations previously conducted alongside trials included in the reviews. A Markov model was used to model cost-effectiveness for a five-year period after the initial operation. The outcomes of the model were presented using a balance sheet approach and as cost per hernia recurrence avoided and cost per extra day at usual activities. Results:Open flat mesh was the most cost-effective method of preventing recurrences. Laparoscopic repair provided a shorter period of convalescence and less long-term pain compared with open flat mesh but was more costly. The mean incremental cost per additional day back at usual activities compared with open flat mesh was €38 and €80 for totally extraperitoneal and transabdominal preperitoneal repair, respectively. Conclusions:Laparoscopic repair is not cost-effective compared with open flat mesh repair in terms of cost per recurrence avoided. Decisions about the use of laparoscopic repair depend on whether the benefits (reduced pain and earlier return to usual activities) outweigh the extra costs and intraoperative risks. On the evidence presented here, these extra costs are unlikely to be offset by the short-term benefits of laparoscopic repair.

A complete accounting of nearby objects -- from the highest-mass white dwarf progenitors down to low-mass brown dwarfs -- is now possible, thanks to an almost complete set of trigonometric parallax determinations from Gaia, ground-based surveys, and Spitzer follow-up. We create a census of objects within a Sun-centered sphere of 20-pc radius and check published literature to decompose each binary or higher-order system into its separate components. The result is a volume-limited census of \\(\\)3,600 individual star formation products useful in measuring the initial mass function across the stellar (\\(<8 M_\\)) and substellar (\\( 5 M_Jup\\)) regimes. Comparing our resulting initial mass function to previous measurements shows good agreement above 0.8\\(M_\\) and a divergence at lower masses. Our 20-pc space densities are best fit with a quadripartite power law, \\((M) = dN/dM M^-\\) with long-established values of \\( = 2.3\\) at high masses (\\(0.55 < M < 8.00 M_\\)) and \\( = 1.3\\) at intermediate masses (\\(0.22 < M < 0.55 M_\\)), but at lower masses we find \\( = 0.25\\) for \\(0.05 < M <0.22 M_\\) and \\( = 0.6\\) for \\(0.01 < M < 0.05 M_\\). This implies that the rate of production as a function of decreasing mass diminishes in the low-mass star/high-mass brown dwarf regime before increasing again in the low-mass brown dwarf regime. Correcting for completeness, we find a star to brown dwarf number ratio of, currently, 4:1, and an average mass per object of 0.41 \\(M_\\).

We used the CHARA Array to directly measure the angular diameter of HD 69830, home to three Neptune mass planets and an asteroid belt. Our measurement of 0.674+/-0.014 milli-arcseconds for the limb-darkened angular diameter of this star leads to a physical radius of R\\(_*\\) = 0.9058\\(\\pm\\)0.0190 R\\sun and luminosity of L* = 0.622+/-0.014 Lsun when combined with a fit to the spectral energy distribution of the star. Placing these observed values on an Hertzsprung-Russel (HR) diagram along with stellar evolution isochrones produces an age of 10.6+/-4 Gyr and mass of 0.863\\(\\pm\\)0.043 M\\sun. We use archival optical echelle spectra of HD 69830 along with an iterative spectral fitting technique to measure the iron abundance ([Fe/H]=-0.04+/-0.03), effective temperature (5385+/-44 K) and surface gravity (log g = 4.49+/-0.06). We use these new values for the temperature and luminosity to calculate a more precise age of 7.5+/-Gyr. Applying the values of stellar luminosity and radius to recent models on the optimistic location of the habitable zone produces a range of 0.61-1.44 AU; partially outside the orbit of the furthest known planet (d) around HD 69830. Finally, we estimate the snow line at a distance of 1.95+/-0.19 AU, which is outside the orbit of all three planets and its asteroid belt.