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1.
Transgenic Res ; 23(6): 1043-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24659218

RESUMO

The Brazilian National Biosafety Committee approved in 2011 a new post release monitoring system for environmental releases of genetically modified organisms. It has a number of novel features in comparison with other established or proposed systems. The new system also allows the proponent to ask for monitoring exemption. General surveillance forms the basis of the monitoring system, similar to the European model, but differs markedly in the way it operates. While the European proposal is based on monitoring measurable variables extracted from environmental observations, from baselines previously established for multiple protection targets, the Brazilian system uses direct alerts of damage, without the aid of baseline values. The strength of the Brazilian form of monitoring is the possibility of generating an information network with the effective participation of many actors from the monitored area. A network constituted by highly qualified members, as proposed elsewhere, is too complex and unrealistic in Brazil and in many other countries. In conclusion, the Brazilian monitoring system is flexible and can be adjusted to the Brazilian reality over the next years, as a response to the ever growing experience in monitoring. It also meets the demands of the Brazilian society for transparency, rational use of resources, opportunity for national companies, and food and environmental biosafety.


Assuntos
Exposição Ambiental/prevenção & controle , Monitoramento Ambiental/métodos , Plantas Geneticamente Modificadas/efeitos adversos , Medição de Risco/métodos , Brasil , Humanos
2.
Science ; 382(6673): 903-907, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37995237

RESUMO

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

4.
Curr Protein Pept Sci ; 11(3): 220-30, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20088771

RESUMO

Defensin, thionin and lipid transfer protein (LTP) gene families, which antimicrobial activity has an attractive use in protein engineering and transgenic production of agronomical important plants, have been here functionally reviewed. Also, a transcriptional overview of a set of plant SuperSAGE libraries and analysis looking for 26 bp tags possibly annotated for those families is presented. Tags differentially expressed (p = 0.05) or constitutively transcribed were identified from leaves or roots SuperSAGE libraries from important Brazilian plant species [cowpea (Vigna unguiculata (L.) Walp.), soybean (Glycine max (L.) Merr.) and modern sugarcane hybrids (Saccharum spp.)] submitted to abiotic [salt (100 mM NaCl) or drought] or biotic stresses [fungus inoculation (Phakopsora pachyrhizi; Asiatic Soyben Rust phytopathogen)]. The diverse transcriptional patterns observed, probably related to the variable range of targets and functions involved, could be the first step to unravel the antimicrobial peptide world and the plant stress response relationship. Moreover, SuperSAGE opens the opportunity to find some SNPs or even rare transcript that could be important on plant stress resistance mechanisms. Putative defensin or LTP identified by SuperSAGE following a specific plant treatment or physiological condition could be useful for future use in genetic improvement of plants.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Plantas/genética , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/química , Sequência de Bases , Brasil , Biologia Computacional , Dados de Sequência Molecular , Plantas/imunologia
5.
Theor Appl Genet ; 112(2): 298-314, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16307229

RESUMO

Sugarcane (Saccharum spp.) is a clonally propagated outcrossing polyploid crop of great importance in tropical agriculture. Up to now, all sugarcane genetic maps had been developed using either full-sib progenies derived from interspecific crosses or from selfing, both approaches not directly adopted in conventional breeding. We have developed a single integrated genetic map using a population derived from a cross between two pre-commercial cultivars ('SP80-180' x 'SP80-4966') using a novel approach based on the simultaneous maximum-likelihood estimation of linkage and linkage phases method specially designed for outcrossing species. From a total of 1,118 single-dose markers (RFLP, SSR and AFLP) identified, 39% derived from a testcross configuration between the parents segregating in a 1:1 fashion, while 61% segregated 3:1, representing heterozygous markers in both parents with the same genotypes. The markers segregating 3:1 were used to establish linkage between the testcross markers. The final map comprised of 357 linked markers, including 57 RFLPs, 64 SSRs and 236 AFLPs that were assigned to 131 co-segregation groups, considering a LOD score of 5, and a recombination fraction of 37.5 cM with map distances estimated by Kosambi function. The co-segregation groups represented a total map length of 2,602.4 cM, with a marker density of 7.3 cM. When the same data were analyzed using JoinMap software, only 217 linked markers were assigned to 98 co-segregation groups, spanning 1,340 cM, with a marker density of 6.2 cM. The maximum-likelihood approach reduced the number of unlinked markers to 761 (68.0%), compared to 901 (80.5%) using JoinMap. All the co-segregation groups obtained using JoinMap were present in the map constructed based on the maximum-likelihood method. Differences on the marker order within the co-segregation groups were observed between the two maps. Based on RFLP and SSR markers, 42 of the 131 co-segregation groups were assembled into 12 putative homology groups. Overall, the simultaneous maximum-likelihood estimation of linkage and linkage phases was more efficient than the method used by JoinMap to generate an integrated genetic map of sugarcane.


Assuntos
Mapeamento Cromossômico/métodos , Cruzamentos Genéticos , Ligação Genética , Funções Verossimilhança , Saccharum/genética , Segregação de Cromossomos , Marcadores Genéticos/genética , Polimorfismo de Fragmento de Restrição
6.
Opt Lett ; 23(18): 1420-2, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18091803

RESUMO

A new type of tomography system based on optical frequency-domain reflectometry is presented. Using an area sensor, the system can simultaneously measure three-dimensional reflectivity distributions in scattering media without the need for mechanical scanning. In preliminary experiments we demonstrate that a target (resolution chart) placed behind biological tissue can be imaged with high depth resolution (47 microm) for a short measurement time.

7.
Kangogaku Zasshi ; 33(7): 10-7, 1969 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-4978825

Assuntos
Pacientes
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