430 research outputs found
Welfare Impacts of Electricity Generation Sector Reform in the Philippines
This paper reports an empirical investigation into the welfare impacts of an introduction of private sector participation into the Philippines electricity generation sector, by liberalizing the market for independent power producers (IPPs) during the power crisis of 1990-1993. This study uses a social cost and benefit analysis. The main benefits came from IPPs, who contributed to resolving the crisis, and promoted economic and social development. Consumers and investors are net gainers, while the Government lost and there was an air pollution cost. The paper concludes that the reform with private sector participation increased social welfare.Electricity; Cost-benefit-analysis; Institutional change.
Medpor implant in cranioorbitomaxillary reconstruction: institutional experience and a review of the literature
ManuscriptAutologous materials remain the gold standard for complex skull base and craniofacial reconstruction, but they carry additional morbidity associated with the second harvest procedure and with prolonged operation time. These autologous materials also resorb in a way that is not predictable, rendering them less ideal in situations where cosmesis and function are of paramount importance to aid with primary healing of the intracranial wound. Medpor porous polyethylene implant is an alloplastic material with unique characteristics that make it an excellent alternative for cranioorbitomaxillary reconstruction. The porous nature of the implant permits the ingrowth of vascularized tissue eventually forming a highly stable complex resistant to infection and deformation. A total of 698 patients undergoing 719 procedures in which Medpor was implanted were reviewed. Two complications occurred that required removal of the implant. On the basis of our results, we believe that the Medpor implant is an excellent alternative to existing alloplastic materials with a low incidence of infection and excellent cosmetic and functional results
Freely decaying weak turbulence for sea surface gravity waves
We study numerically the generation of power laws in the framework of weak
turbulence theory for surface gravity waves in deep water. Starting from a
random wave field, we let the system evolve numerically according to the
nonlinear Euler equations for gravity waves in infinitely deep water. In
agreement with the theory of Zakharov and Filonenko, we find the formation of a
power spectrum characterized by a power law of the form of .Comment: 4 pages, 3 figure
The Hyper Suprime-Cam SSP Survey: Overview and Survey Design
Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of
the 8.2m Subaru telescope on the summit of Maunakea in Hawaii. A team of
scientists from Japan, Taiwan and Princeton University is using HSC to carry
out a 300-night multi-band imaging survey of the high-latitude sky. The survey
includes three layers: the Wide layer will cover 1400 deg in five broad
bands (), with a point-source depth of . The
Deep layer covers a total of 26~deg in four fields, going roughly a
magnitude fainter, while the UltraDeep layer goes almost a magnitude fainter
still in two pointings of HSC (a total of 3.5 deg). Here we describe the
instrument, the science goals of the survey, and the survey strategy and data
processing. This paper serves as an introduction to a special issue of the
Publications of the Astronomical Society of Japan, which includes a large
number of technical and scientific papers describing results from the early
phases of this survey.Comment: 14 pages, 7 figures, 5 tables. Corrected for a typo in the
coordinates of HSC-Wide spring equatorial field in Table
S2COSMOS: evolution of gas mass with redshift using dust emission
We investigate the evolution of the gas mass fraction for galaxies in the COSMOS field using submillimetre emission from dust at 850μm. We use stacking methodologies on the 850 μm S2COSMOS map to derive the gas mass fraction of galaxies out to high redshifts, 0 ≤ z ≤ 5, for galaxies with stellar masses of 109.
North Ecliptic Pole merging galaxy catalogue
Aims. We aim to generate a catalogue of merging galaxies within the 5.4 sq. deg. North Ecliptic Pole over the redshift range 0.0 \u3c z \u3c 0.3. To do this, imaging data from the Hyper Suprime-Cam are used along with morphological parameters derived from these same data.
Methods. The catalogue was generated using a hybrid approach. Two neural networks were trained to perform binary merger non-merger classifications: one for galaxies with z \u3c 0.15 and another for 0.15 ≤ z \u3c 0.30. Each network used the image and morphological parameters of a galaxy as input. The galaxies that were identified as merger candidates by the network were then visually checked by experts. The resulting mergers will be used to calculate the merger fraction as a function of redshift and compared with literature results.
Results. We found that 86.3% of galaxy mergers at z \u3c 0.15 and 79.0% of mergers at 0.15 ≤ z \u3c 0.30 are expected to be correctly identified by the networks. Of the 34 264 galaxies classified by the neural networks, 10 195 were found to be merger candidates. Of these, 2109 were visually identified to be merging galaxies. We find that the merger fraction increases with redshift, consistent with literature results from observations and simulations, and that there is a mild star-formation rate enhancement in the merger population of a factor of 1.102 ± 0.084
First Data Release of the Hyper Suprime-Cam Subaru Strategic Program
The Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) is a three-layered
imaging survey aimed at addressing some of the most outstanding questions in
astronomy today, including the nature of dark matter and dark energy. The
survey has been awarded 300 nights of observing time at the Subaru Telescope
and it started in March 2014. This paper presents the first public data release
of HSC-SSP. This release includes data taken in the first 1.7 years of
observations (61.5 nights) and each of the Wide, Deep, and UltraDeep layers
covers about 108, 26, and 4 square degrees down to depths of i~26.4, ~26.5, and
~27.0 mag, respectively (5sigma for point sources). All the layers are observed
in five broad bands (grizy), and the Deep and UltraDeep layers are observed in
narrow bands as well. We achieve an impressive image quality of 0.6 arcsec in
the i-band in the Wide layer. We show that we achieve 1-2 per cent PSF
photometry (rms) both internally and externally (against Pan-STARRS1), and ~10
mas and 40 mas internal and external astrometric accuracy, respectively. Both
the calibrated images and catalogs are made available to the community through
dedicated user interfaces and database servers. In addition to the pipeline
products, we also provide value-added products such as photometric redshifts
and a collection of public spectroscopic redshifts. Detailed descriptions of
all the data can be found online. The data release website is
https://hsc-release.mtk.nao.ac.jp/.Comment: 34 pages, 20 figures, 7 tables, moderate revision, accepted for
publication in PAS
Relationship Between Nutritional Habits and Hair Calcium Levels in Young Women
The present study was conducted to investigate whether hair calcium levels are related to nutritional habits, selected status parameters, and life-style factors in young women. Eighty-five healthy female students neither pregnant nor lactating, using no hair dyes or permanents were recruited for the study. Food consumption data, including fortified products and dietary supplements were collected with 4-day records. The calcium levels in hair and serum were analyzed by atomic absorption spectroscopy. Serum osteocalcin and the C-terminal telopeptide of type I collagen were assayed by ELISA. The women were divided into four groups according to their total vitamin D and calcium intakes and hair calcium levels. At adequate calcium intake and comparable serum bone biomarker levels, supplemental vitamin D increased the hair calcium levels. On the other hand, at lower than estimated adequate requirement of vitamin D intake the hair calcium levels were comparable in women with low calcium intakes but consuming high amounts of meat products or those whose diets were rich in dairy products, possibly due to homeostatic mechanisms. Elevated hair calcium was seen in 25% of subjects and could not be related to nutritional or life-style factors. The results show that the hair calcium levels were weakly related to the quality of diet, with some synergistic interactions between nutrients, especially vitamin D and magnesium
- …