NAVPRO 3.0: tutorial de instalação e utilização.

Este documento apresenta os procedimentos para instalação e utilização do sistema NAVPRO 3.0, desenvolvido para o processamento automático e geração de produtos de imagens do sensor Advanced Very High Resolution Radiometer (AVHRR) a bordo dos satélites da National Oceanic Atmospheric Administration (NOAA). O sistema NAVPRO foi criado pela Embrapa Informática Agropecuária em parceria com a Universidade Estadual de Campinas (Unicamp), que contou com o repasse do pacote computacional NAV (NAVigation), desenvolvido pelo Colorado Center for Astrodynamics Research (CCAR), da Universidade do Colorado, Boulder, EUA. O diferencial do sistema é seu método de georreferenciamento automático e preciso, capaz de gerar imagens com deslocamentos máximos de 1 pixel, valor aceito em aplicações envolvendo dados de baixa resolução espacial.

LyonPotpourri 3.0

A set of audio signal processing software for Max/MSP and Pure Data.

Targeted 3' processing of antisense transcripts triggers Arabidopsis FLC chromatin silencing.

Noncoding RNA is emerging as an important regulator of gene expression in many organisms. We are characterizing RNA-mediated chromatin silencing of the Arabidopsis major floral repressor gene, FLC. Through suppressor mutagenesis, we identify a requirement for CstF64 and CstF77, two conserved RNA 3'-end-processing factors, in FLC silencing. However, FLC sense transcript 3' processing is not affected in the mutants. Instead, CstF64 and CstF77 are required for 3' processing of FLC antisense transcripts. A specific RNA-binding protein directs their activity to a proximal antisense polyadenylation site. This targeted processing triggers localized histone demethylase activity and results in reduced FLC sense transcription. Targeted 3' processing of antisense transcripts may be a common mechanism triggering transcriptional silencing of the corresponding sense gene.

A 330-360 GHz spectral survey of G34.3+0.15 - III. The outer halo

We have undertaken a 330-360 GHz molecular line survey of the halo gas surrounding the hot core associated with G34.26+0.15. In contrast to our molecular line survey of the hot core itself, where 338 lines from at least 38 species were detected, only 18 lines from 9 species were detected in the halo. The lines are mainly single transitions of simple di atomic and triatomic molecules. Lower limits to their column densities have been evaluated by an LTE method. In the case of methanol, where four transitions were detected, the rotation temperature and column density have been evaluated by the rotation diagram technique. We have modified the previous depth-dependent chemical model developed in Paper II to calculate the column densities observed along a general line of sight drawn through the model cloud. The model is also extended to produce beam-averaged column densities for better comparison with those observed. We compare the model column densities with those observed and make recommendations for future depth-dependent chemical modelling of hot cores.

A 330-360 GHz spectral survey of G34.3+0.15 .2. Chemical modelling

We describe a detailed depth-and time-dependent model of the molecular cloud associated with the ultracompact H II region G 34.3+0.15. Previous work on observations of NH3 and CS indicates that the molecular cloud has three distinct physical components:- an ultracompact hot core, a compact hot core and an extended halo. We have used the physical parameters derived from these observations as input to our detailed chemical kinetic modelling. The results of the model calculations are discussed with reference to the different chemistries occuring in each component and are compared with abundances derived from our recent spectral line survey of G 34.3+0.15 (Paper I).

A 330-360 GHz spectral survey of G 34.3+0.15 .1. Data and physical analysis

A 330--360 GHz spectral survey of the hot molecular core associated with the 'cometary' ultracompact HII region G 34.3+/-0.15 observed with the James Clerk Maxwell Telescope has detected 338 spectral lines from at least 35 distinct chemical species plus 19 isotopomers. 70 lines remain unidentified. Chemical abundance and rotation temperature have been determined by rotation diagram analysis for 12 species, and lower limits to abundance found for 38 others.

THE DETECTION OF HOT ETHANOL IN G34.3+0.15

Hot molecular cores in star-forming regions are known to have gas-phase chemical compositions determined by the evaporation of material from the icy mantles of interstellar grains, followed by subsequent reactions in the gas phase. Current models suggest that the evaporated material is rich in hydrogenated species, such as water, methane and methanol. In this paper, we report the detection of 14 rotational transitions of ethanol in the submillimetre spectrum of the molecular cloud associated with the ultra-compact H II region G34.3+0.15. We derive a rotation temperature of 125 K and a beam-averaged column density of 2.0x10(15) cm(-2), corresponding to a fractional abundance on the order of 4x10(-9). This large abundance, which is a lower limit due to the likelihood of beam dilution, cannot be made by purely gas-phase processes, and we conclude that the ethanol must be formed efficiently in the grain surface chemistry. Since it has been argued previously that methanol is formed via surface chemistry, it appears that alcohol formation may be a natural by-product of surface reactions.