IMI resistance associated to crop-weed hybridization in a natural Brassica rapa population: characterization and fate.

Wild turnip (Brassica rapa) is a common weed and a close relative to oilseed rape (Brassica napus). The Clearfield® production system is a highly adopted tool which provides an alternative solution for weed management, but its efficiency is threatened by gene transfer from crop to weed relatives. Crop-weed hybrids with herbicide resistance were found in the progeny of a B. rapa population gathered from a weedy stand on the borders of an oilseed rape (B. napus) imidazolinone (IMI)-resistant crop. Interspecific hybrids were confirmed by morphological traits in the greenhouse and experimental field, survival after imazethapyr applications, DNA content through flow cytometry, and pollen viability. The transference of herbicide resistance was demonstrated even in a particular situation of pollen competition between both an herbicide-resistant crop and a non-resistant crop. However, IMI resistance was not found in further generations collected at the same location. These results verify gene transmission from oilseed rape to B. rapa in the main crop area in Argentina where resistant and susceptible varieties are found and seed loss and crop volunteers are common. Hybridization, introgression, and herbicide selection would be associated with the loss of effectiveness of IMI technology.

Random field-union intersection tests for EEG/MEG imaging.

Electrophysiological (EEG/MEG) imaging challenges statistics by providing two views of the same spatiotemporal data: topographic and tomographic. Until now, statistical tests for these two situations have developed separately. This work introduces statistical tests for assessing simultaneously the significance of spatiotemporal event-related potential/event-related field (ERP/ERF) components and that of their sources. The test for detecting a component at a given time instant is provided by a Hotelling's T(2) statistic. This statistic is constructed in such a manner to be invariant to any choice of reference and is based upon a generalized version of the average reference transform of the data. As a consequence, the proposed test is a generalization of the well-known Global Field Power statistic. Consideration of tests at all time instants leads to a multiple comparison problem addressed by the use of Random Field Theory (RFT). The Union-Intersection (UI) principle is the basis for testing hypotheses about the topographic and tomographic distributions of such ERP/ERF components. The performance of the method is illustrated with actual EEG recordings obtained from a visual experiment of pattern reversal stimuli.

Brain potentials reflect residual face processing in a case of prosopagnosia.

Here, ERPs were employed to characterise the residual face processing of FE, a patient with extensive damage to the ventral temporal-occipital cortex and a dense prosopagnosia. Alarge N170 was present in FE and he performed well in tests of face structural processing. Covert recognition of the faces of personal acquaintances was demonstrated with P300 oddball experiments. The onset latency of the P300 effect was normal, indicating fast availability of covert memory. The scalp topography of this component in FE was different from that of the P3b, presenting a centro-frontal maximum. FE also presented larger skin conductance responses to familiar than to unfamiliar faces. The amplitudes of both the single-trial P300s and the SCRs triggered by familiar faces were positively correlated with the degree of person-familiarity that FE had for the poser. He performed at chance when asked to select between the face of a familiar person and that of an unfamiliar person on the basis of explicit recognition, whereas he selected more the previously known face if the forced choice was based on trustworthiness or a vague sense of familiarity. The results suggest that in FE, early face processing was relatively intact and covert recognition was fast. Neural structures involved in the processing of emotional or social cues possibly mediate the covert recognition present in FE.

Anestesia pelo enflurano, com ou sem succinicolina, em estrabicos. Estudo da histologia muscular e perfil dos elementos enzimaticos e bioquimicos. / Enflurane anesthesia with and without succinylcholine in strabismus.Study of muscular histology and profile of enzymatic and biochemical elements

Dez pacientes, ASA I, anestesiados com enflurano para correcao de estrabismo, foram divididos em dois grupos semelhantes, dos quais, em um foi utilizada a succinilcolina para a intubacao traqueal.Determinaram-se, em todos os pacientes, os valores de aldolase, desidrogenase latica, transaminases glutamicas oxalacetica e piruvica, creatinofosfoquinase, glicemia e potassemia em repouso, apos exercicio intenso e durante a anestesia (depois da intubacao, 30' apos e ao final do procedimento).Biopsou-se, ainda, a musculatura extraocular comprometida e o gastrocnemio de alguns pacientes para estudo ultramicroscopico.Os resultados demonstraram uma diminuicao da atividade enzimatica, que se recuperou ao final da anestesia, exceto a CPK que aumentou progressivamente. A glicemia aumentou e cairam a potassemia e a tensao arterial. A ultramicroscopia mostrou degeneracao conjuntiva com atividade inflamatoria nos musculos extraoculares e uma proliferacao com aumento do diametro do sistema muscular transverso no gastrocnemio de alguns pacientes. O quadro enzimatico pode ser responsabilizado por diminuicao do fluxo sanguineo hepatico. As alteracoes da glicemia, potassio e tensao arterial aparentam ser efeito direto do agente. Nao houve evidencias para classificar os estrabicos como miopatas sistemicos