Comment on ``Periodic wave functions and number of extended states in random dimer systems'

There are no periodic wave-functions in the RDM but close to the critical energies there exist periodic envelopes. These envelopes are given by the non-disordered properties of the system.Comment: RevTex file, 1 page, Comment X. Huang, X. Wu and C. Gong, Phys. Rev. B 55, 11018 (1997

Comparing the Host Galaxies of Type Ia, Type II and Type Ibc Supernovae

We compare the host galaxies of 902 supernovae, including SNe Ia, SNe II and SNe Ibc, which are selected by cross-matching the Asiago Supernova Catalog with the SDSS Data Release 7. We further selected 213 galaxies by requiring the light fraction of spectral observations $>$15%, which could represent well the global properties of the galaxies. Among them, 135 galaxies appear on the Baldwin-Phillips-Terlevich diagram, which allows us to compare the hosts in terms of star-forming, AGNs (including composites, LINERs and Seyfert 2s) and "Absorp" (their related emission-lines are weak or non-existence) galaxies. The diagrams related to parameters D$_n$(4000), H$\delta_A$, stellar masses, SFRs and specific SFRs for the SNe hosts show that almost all SNe II and most of SNe Ibc occur in SF galaxies, which have a wide range of stellar mass and low D$_n$(4000). The SNe Ia hosts as SF galaxies follow similar trends. A significant fraction of SNe Ia occurs in AGNs and Absorp galaxies, which are massive and have high D$_n$(4000). The stellar population analysis from spectral synthesis fitting shows that the hosts of SNe II have a younger stellar population than hosts of SNe Ia. These results are compared with those of the 689 comparison galaxies where the SDSS fiber captures less than 15% of the total light. These comparison galaxies appear biased towards higher 12+log(O/H) ($\sim$0.1dex) at a given stellar mass. Therefore, we believe the aperture effect should be kept in mind when the properties of the hosts for different types of SNe are discussed.Comment: 15 pages, 9 figure

An analysis of effects of socio-economic variables on fish production of small farmers in the state of Tocantins, Brazil.

Fish farming familiar stands out for its strong social and economic appeal, given its potential in terms of food security, income generation and diversification of rural establishments. In this context, it is important that the state of Tocantins has significant deficiencies in terms of their social and economic development.ICAS 2013

Como multiplicar os peixes? Perspectivas da aquicultura brasileira.

A atividade, que corresponde ao cultivo de organismos aquáticos, como a criação de peixes, moluscos, crustáceos etc, vem apresentando um espetacular crescimento nos últimos anos. Para se ter ideia, a produção mundial aumentou em quase 12 vezes nas últimas três décadas, crescendo a uma taxa média de 8,8% ao ano e atingindo 63,6 milhões de toneladas em 2011. Outro ponto que conta a favor do setor aquícola é o fato de a carne de pescado (carne advinda da pesca e da aquicultura) ser a mais consumida no mundo e o setor da pesca (que corresponde unicamente à extração de organismos aquáticos do meio natural) vir apresentando estabilidade na sua produção nos últimos anos

Fish consumption in Brazil: is the internal market able to accommodate the strong growth projected for Brazilian aquaculture?

This trend of growth of aquaculture is also repeated in Brazil. The sector grew by 31.2% in annual production between 2008 and 2010, reaching 479,399 tons. It is in this context of expected strong growth of aquaculture production in Brazil in the coming years as the need arises to check the ability of the market to absorb this increased supply.ICAS 2013

Estimation of carrier life time from intrinsic photoluminescence of ZnO

Comprehensive knowledge of the optical properties, particularly of the room temperature (RT) photoluminescence (PL), of ZnO is essential for the future employment of this wideband gap (~3.3 eV at 300 K) II-VI compound semiconductor in photonic and optoelectronic device structures [1]. Hence, vigorous research activities on ZnO thin films, epilayers, and crystals took place during the last two decades, encompassing a vast variety of effects and phenomena such as birefringence, photocurrent, PL including sub-band gap emission, reflectance, transmittance, excitonic properties, Raman modes, and absorption edge steepness [1-4]. However, despite that large body of knowledge and its essential importance for light emitting processes, a discussion of the ZnO PL lineshape is not found in the literature [5]

Intrinsic photoluminescence stokes shift in thin-film cadmium sulfide

Exciting a semiconductor through light absorption produces photoluminescence (PL). In general, the emitted energy is lower than the energy absorbed. The phenomenon, first discovered in the nineteenth century, is known as Stokes shift energy [1]. The change in energy (AS t o k e s), crucial for the information about the phonon relaxation in the material and with importance in light emitting devices, has not been investigated experimentally very systematically [2]. In this project, we present the observation of the intrinsic photoluminescence Stokes shift in a semiconductor

Multiwavelength Observations of one Galaxy in Marano Field

We report the multiwavelength observations of one intermediate redshift (z=0.3884) galaxy in the Marano Field. These data include ISOCAM middle infrared, VLT/FORS2 spectroscopic and photometric data, associated with the ATCA 1.4 GHz radio and ROSAT PSPC X-ray observations from literature. The Spectral Energy Distribution obtained by VLT spectroscopy exhibits its early-type galaxy property, while, in the same time, it has obvious [OIII]5007 emission line. The diagnostic diagram from the optical emission line ratios shows its Seyfert galaxy property. Its infrared-radio relation follows the correlation of sources detected at 15 \mu and radio. It has a high X-ray luminosity of 1.26*10^{43} ergs/s, which is much higher than the general elliptical galaxies s with the similar B band luminosity, and is about 2 orders of magnitude higher than the derived value from the star forming tracer, the FIR luminosity. This means that the X-ray sources of this galaxy are not stellar components, but the AGN is the dominant component.Comment: 6 pages, 1 PS figure and 4 tables. Publication in ChJAA, Suppl., the Special Issue for The Fifth Microquasar Workshop 2004: http://chjaa.bao.ac.cn/, 2005, Vol.5, 335-34

Deep Galaxy survey at 6.75 micron with the ISO satellite

Deep 6.75um mid-IR ISOCAM observations were obtained of the Canada-France Redshift Survey (CFRS) 1415+52 field with the Infrared Space Observatory. The identification of the sources with optical counterparts is described in detail, and a classification scheme is devised which depends on the S/N of the detection and the inverse probability of chance coincidence. 83% of the 54 ISOCAM sources are identified with Iab<23.5 counterparts. The (I-K)ab colors, radio properties, spectrophotometric properties and frequency of nuclear activity of these counterparts differ on average from those of typical CFRS galaxies. CFRS spectra are available for 21 of the sources which have Iab <= 22.5 (including 7 stars). Most of the strongest sources are stars or AGN. Among the non--stellar counterparts with spectra, 40% are AGNs, and 53% are galaxies that display star formation activity and/or significant contributions of A stars. The ISOCAM sources also display an IR excess, even when compared with heavily-reddened local starburst galaxies. An upper limit of 30% of extragalactic ISO sources could be at z>1 of the 44 S6.75um > 150uJy sources which are non-stellar (7 "spectroscopic" and 3 "photometric" stars excluded)Comment: 13 pages, 12 figures. Accepted for publication in A