Regulated deficit irrigation - a means to control growth in woody ornamentals

Improving plant quality and the uniformity of a crop are major objectives for growers of ornamental nursery stock. The potential to control excess vigour and to improve quality through regulated deficit irrigation (RDI) was investigated using a range of woody ornamental species. RDI regimes reduced vegetative growth consistently across different species and growing seasons. Plants adapted to reduced water supplies primarily via stomatal control, but also by osmotic adjustment when grown under the most severe RDI regimes. Only plants exposed to <= 25% of potential evapo-transpiration demonstrated any evidence of leaf injury, and the extent was slight. Growth inhibition increased as the severity of RDI increased. Improvements in quality were attained through a combination of shorter internodes and final shoot lengths, yet the number of 'formative' primary shoots remained unaffected. Compact, well-branched plants could be formed without a requirement for mid-season pruning. In addition to severity, the timing of RDI also influenced growth responses. Applying 50% ETp for 8 weeks during July-August resulted in the formation of good quality plants, which retained their shape until the following Spring. Re-positioning irrigation drippers within the pots of well-watered plants, in an attempt to induce a partial root drying (PRD) treatment, reduced growth, but not significantly. The adoption of irrigation scheduling, based on 50-100% ETp, has the potential to improve commercial crop quality across a range of ornamental species.

Orientation coding: a specific deficit in Williams syndrome?

Williams syndrome (WS) is a rare genetic disorder with a unique cognitive profile in which verbal abilities are markedly stronger than visuospatial abilities. This study investigated the claim that orientation coding is a specific deficit within the visuospatial domain in WS. Experiment I employed a simplified version of the Benton Judgement of Line Orientation task and a control, length-matching task. Results demonstrated comparable levels of orientation matching performance in the group with WS and a group of typically developing (TD) controls matched by nonverbal ability, although it is possible that floor effects masked group differences. A group difference was observed in the length-matching task due to stronger performance from the control group. Experiment 2 employed an orientation-discrimination task and a length-discrimination task. Contrary to previous reports, the results showed that individuals with WS were able to code by orientation to a comparable level as that of their matched controls. This demonstrates that, although some impairment is apparent, orientation coding does not represent a specific deficit in WS. Comparison between Experiments I and 2 suggests that orientation coding is vulnerable to task complexity. However, once again, this vulnerability does not appear to be specific to the population with WS, as it was also apparent in the TD controls.

Disorder-specific functional abnormalities during sustained attention in youth with Attention Deficit Hyperactivity Disorder (ADHD) and with Autism

Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) are often comorbid and share behavioural-cognitive abnormalities in sustained attention. A key question is whether this shared cognitive phenotype is based on common or different underlying pathophysiologies. To elucidate this question, we compared 20 boys with ADHD to 20 age and IQ matched ASD and 20 healthy boys using functional magnetic resonance imaging (fMRI) during a parametrically modulated vigilance task with a progressively increasing load of sustained attention. ADHD and ASD boys had significantly reduced activation relative to controls in bilateral striato–thalamic regions, left dorsolateral prefrontal cortex (DLPFC) and superior parietal cortex. Both groups also displayed significantly increased precuneus activation relative to controls. Precuneus was negatively correlated with the DLPFC activation, and progressively more deactivated with increasing attention load in controls, but not patients, suggesting problems with deactivation of a task-related default mode network in both disorders. However, left DLPFC underactivation was significantly more pronounced in ADHD relative to ASD boys, which furthermore was associated with sustained performance measures that were only impaired in ADHD patients. ASD boys, on the other hand, had disorder-specific enhanced cerebellar activation relative to both ADHD and control boys, presumably reflecting compensation. The findings show that ADHD and ASD boys have both shared and disorder-specific abnormalities in brain function during sustained attention. Shared deficits were in fronto–striato–parietal activation and default mode suppression. Differences were a more severe DLPFC dysfunction in ADHD and a disorder-specific fronto–striato–cerebellar dysregulation in ASD.

Food restriction reverses the hyper-muscular phenotype and force generation capacity deficit of the myostatin null mouse

Food restriction has a great impact on skeletal muscle mass by inducing muscle protein breakdown to provide substrates for energy production through gluconeogenesis. Genetic models of hyper-muscularity interfere with the normal balance between protein synthesis and breakdown which eventually results in extreme muscle growth. Mutations or deletions in the myostatin gene result in extreme muscle mass. Here we evaluated the impact of food restriction for a period of 5 weeks on skeletal muscle size (i.e., fibre cross-sectional area), fibre type composition and contractile properties (i.e., tetanic and specific force) in myostatin null mice. We found that this hyper-muscular model was more susceptible to catabolic processes than wild type mice. The mechanism of skeletal muscle mass loss was examined and our data shows that the myostatin null mice placed on a low calorie diet maintained the activity of molecules involved in protein synthesis and did not up-regulate the expression of genes pivotal in ubiquitin-mediated protein degradation. However, we did find an increase in the expression of genes associated with autophagy. Surprisingly, the reduction on muscle size was followed by improved tetanic and specific force in the null mice compared to wild type mice. These data provide evidence that food restriction may revert the hyper-muscular phenotype of the myostatin null mouse restoring muscle function.

Examining the large-scale spatial coherence of European drought using regional indicators of precipitation and streamflow deficit

Droughts tend to evolve slowly and affect large areas simultaneously, which suggests that improved understanding of spatial coherence of drought would enable better mitigation of drought impacts through enhanced monitoring and forecasting strategies. This study employs an up-to-date dataset of over 500 river flow time series from 11 European countries, along with a gridded precipitation dataset, to examine the spatial coherence of drought in Europe using regional indicators of precipitation and streamflow deficit. The drought indicators were generated for 24 homogeneous regions and, for selected regions, historical drought characteristics were corroborated with previous work. The spatial coherence of drought characteristics was then examined at a European scale. Historical droughts generally have distinctive signatures in their spatio-temporal development, so there was limited scope for using the evolution of historical events to inform forecasting. Rather, relationships were explored in time series of drought indicators between regions. Correlations were generally low, but multivariate analyses revealed broad continental-scale patterns, which appear to be related to large-scale atmospheric circulation indices (in particular, the North Atlantic Oscillation and the East Atlantic West Russia pattern). A novel methodology for forecasting was developed (and demonstrated with reference to the United Kingdom), which predicts drought from drought i.e. uses spatial coherence of drought to facilitate early warning of drought in a target region, from drought which is developing elsewhere in Europe.Whilst the skill of the methodology is relatively modest at present, this approach presents a potential new avenue for forecasting, which offers significant advantages in that it allows prediction for all seasons, and also shows some potential for forecasting the termination of drought conditions.

Disorder-specific functional abnormalities during temporal discounting in youth with Attention Deficit Hyperactivity Disorder (ADHD), Autism and comorbid ADHD and Autism

Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) are often comorbid and share cognitive abnormalities in temporal foresight. A key question is whether shared cognitive phenotypes are based on common or different underlying pathophysiologies and whether comorbid patients have additive neurofunctional deficits, resemble one of the disorders or have a different pathophysiology. We compared age- and IQ-matched boys with non-comorbid ADHD (18), non-comorbid ASD (15), comorbid ADHD and ASD (13) and healthy controls (18) using functional magnetic resonance imaging (fMRI) during a temporal discounting task. Only the ASD and the comorbid groups discounted delayed rewards more steeply. The fMRI data showed both shared and disorder-specific abnormalities in the three groups relative to controls in their brain-behaviour associations. The comorbid group showed both unique and more severe brain-discounting associations than controls and the non-comorbid patient groups in temporal discounting areas of ventromedial and lateral prefrontal cortex, ventral striatum and anterior cingulate, suggesting that comorbidity is neither an endophenocopy of the two pure disorders nor an additive pathology.

Pre-conditioning the epigenetic response to high vapor pressure deficit increases the drought tolerance of Arabidopsis thaliana

Epigenetic modification of the genome via cytosine methylation is a dynamic process that responds to changes in the growing environment. This modification can also be heritable. The combination of both properties means that there is the potential for the life experiences of the parental generation to modify the methylation profiles of their offspring and so potentially to ‘pre-condition’ them to better accommodate abiotic conditions encountered by their parents. We recently identified high vapor pressure deficit (vpd)-induced DNA methylation at two gene loci in the stomatal development pathway and an associated reduction in leaf stomatal frequency.1 Here, we test whether this epigenetic modification pre-conditioned parents and their offspring to the more severe water stress of periodic drought. We found that three generations of high vpd-grown plants were better able to withstand periodic drought stress over two generations. This resistance was not directly associated with de novo methylation of the target stomata genes, but was associated with the cmt3 mutant’s inability to maintain asymmetric sequence context methylation. If our finding applies widely, it could have significant implications for evolutionary biology and breeding for stressful environments.

Varieties of semantic ‘access’ deficit in Wernicke’s aphasia and semantic aphasia

Comprehension deficits are common in stroke aphasia, including in cases with (i) semantic aphasia (SA), characterised by poor executive control of semantic processing across verbal and nonverbal modalities, and (ii) Wernicke’s aphasia (WA), associated with poor auditory-verbal comprehension and repetition, plus fluent speech with jargon. However, the varieties of these comprehension problems, and their underlying causes, are not well-understood. Both patient groups exhibit some type of semantic ‘access’ deficit, as opposed to the ‘storage’ deficits observed in semantic dementia. Nevertheless, existing descriptions suggest these patients might have different varieties of ‘access’ impairment – related to difficulty resolving competition (in SA) vs. initial activation of concepts from sensory inputs (in WA). We used a case-series design to compare WA and SA patients on Warrington’s paradigmatic assessment of semantic ‘access’ deficits. In these verbal and non-verbal matching tasks, a small set of semantically-related items are repeatedly presented over several cycles so that the target on one trial becomes a distractor on another (building up interference and eliciting semantic ‘blocking’ effects). WA and SA patients were distinguished according to lesion location in the temporal cortex, but in each group, some individuals had additional prefrontal damage. Both of these aspects of lesion variability – one that mapped onto classical ‘syndromes’ and one that did not – predicted aspects of the semantic ‘access’ deficit. Both SA and WA cases showed multimodal semantic impairment, although as expected the WA group showed greater deficits on auditory-verbal than picture judgements. Distribution of damage in the temporal lobe was crucial for predicting the initially beneficial effects of stimulus repetition: WA cases showed initial improvement with repetition of words and pictures, while in SA, semantic access was initially good but declined in the face of competition from previous targets. Prefrontal damage predicted the harmful effects of repetition: the ability to re-select both word and picture targets in the face of mounting competition was linked to left prefrontal damage in both groups. Therefore, SA and WA patients have partially distinct impairment of semantic ‘access’ but, across these syndromes, prefrontal lesions produce declining comprehension with repetition in both verbal and non-verbal tasks.

Morphometric analysis of the AMPA-type neurons in the Deiters vestibular complex of the chick brain

Chicken (Gallus gallus) brains were used to investigate the typology and the immunolabel pattern for the subunits composing the AMPA-type glutamate receptors (GluR) of hindbrain neurons of the dorsal (dND) and ventral nuclei (vND) of the Deiter`s vestibular complex (CD), which is the avian correspondent of the lateral vestibular nucleus (LVN) of mammals. Our results revealed that neurons of both divisions were poor in GluR1. The vND, the GluR2/3+ and GluR4+ label presented no area or neuronal size preference, although most neurons were around 75%. The dND neurons expressing GluR2/3 are primarily around 85%, medium to large-sized 85%, and predominantly 60% located in the medial portion of the rostral pole and in the lateral portion of the caudal pole. The majority of dND neurons containing GluR4 are also around 75%, larger (70% are large and giant), exhibiting a distribution that seems to be complementary to that of GluR2/3+ neurons. This distinct arrangement indicates functional differences into and between the DC nuclei, also signaling that such variation could be attributed to the diverse nature of the subunit composition of the GluRs. Discussion addresses the morphological and functional correlation of the avian DC with the LVN of mammals in addition to the high morphological correspondence, To include these data into the modern comparative approach we propose to adopt a similar nomenclature for the avian divisions dND and vND that could be referred as dLVN and vLVN. (C) 2008 Elsevier B.V. All rights reserved.

Democratic Deficit in the EU : Towards Parliamentary Democracy?!

Nowadays, the western societies are based on parliamentary democracy. Therefore, weak legislative power of the European Parliament is alleged for the democratic deficit in the EU. How it can be possible that the parliamentary democracy which is practiced on the national level can be achieved beyond the nation-states without diminishing the democracy at the nation-states? If not, how legitimacy can be obtained so that the continued existence and expansion of the EU should be justified? Since expectations for democratization of the EU are still unmet, finding answers to the actual questions is a great appeal. The thesis will explore the fundamental debates and arguments contributing to the democracy in the EU through the parliaments. I will try to reflect to the different ways of thinking and the prospects of establishing parliamentary democracy beyond the nation states.

Língua estrangeira moderna no vestibular : que conhecimento lingüístico é exigido nas provas de língua espanhola?

Este trabalho desenvolve-se na área da Lingüística Aplicada ao Ensino do Espanhol como Língua Estrangeira. O propósito é o de examinar as provas de espanhol dos vestibulares de três Instituições de Ensino Superior de Porto Alegre e Grande Porto Alegre, Rio Grande do Sul, Brasil, no período compreendido entre os anos de 1996 a 2000, para depreender delas o tipo de conhecimento lingüístico exigido do candidato. Empregamos como base metodológica a avaliação formativa, com enfoque qualitativo na interpretação das informações e quantitativo na coleta e exposição dos dados, resultando em um quadro descritivo da realidade das provas examinadas. O estudo caracteriza-se como exploratório, sem levantamento de hipóteses. A falta de pesquisas sobre as provas de espanhol nos vestibulares, e de literatura específica sobre o assunto resultou na busca de uma base teórica que desse suporte a uma análise clara e ajustada ao objetivo. Teóricos clássicos como Saussure (1974), Bloom (1983) até autores contemporâneos como Ortega Olivares (1990), Orlandi (1987) e Wiggins e McThige (1998) constituíram o referencial teórico do trabalho. A análise das provas de espanhol foi organizada tendo em vista os conceitos de Orlandi sobre tipos de discurso, o de Wiggins e MacThige sobre os tipos de perguntas de compreensão e de Ortega Olivares sobre o conceito de gramática. Os resultados apontam para a presença dos discursos autoritário, lúdico e polêmico com a predominância desse último. As perguntas de unidade preponderam sobre as do tipo essencial e o conhecimento gramatical, em grande parte, ainda de base estruturalista indicam que uma nova postura deva ser adotada em relação à elaboração das provas de vestibular e à abordagem do conteúdo.

Concurso vestibular : uma análise tipológica e enunciativa

Neste trabalho, faz-se uma análise dos textos das provas do Concurso Vestibular UFRGS 2001 a partir da Lingüística Textual, tendo-se como referência Teorias da Enunciação. Busca-se verificar como se caracterizam os textos das provas do ponto de vista lingüístico. Para isso, baseando-se em elementos de textualização, analisam-se alguns aspectos que se destacaram na organização estrutural e enunciativa dos textos das provas. Nesta análise, faz-se também uma tipologização das seqüências textuais que aparecem nos textos das questões das provas. Conclui-se que os textos das provas do vestibular da UFRGS de 2001 caracterizam-se por estabelecer uma aparente proximidade do enunciador com o leitor por meio de alguns recursos de modalização enunciativa e, ao mesmo tempo, por uma tentativa de não-marcação da enunciação, tendo em vista se inserirem numa situação formal de avaliação. A forma como se compõem os textos das provas revela a tentativa de um máximo controle do sentido. É necessário, durante a elaboração das provas, que sejam previstos os conhecimentos e inferências que o leitor poderá fazer a partir de seu conhecimento de mundo e do conhecimento do conteúdo que está sendo avaliado. Por sua vez, o leitor precisa relacionar e mobilizar o seu conhecimento de mundo e do conteúdo avaliado com o que supostamente está de acordo com o mundo científico em que se insere a prova. Quanto mais os conhecimentos de mundo e de conteúdo do produtor e do leitor-candidato coincidirem, maior será a possibilidade de êxito do candidato nas provas. Este trabalho é de interesse especialmente aos estudiosos de língua em seus aspectos textuais e enunciativos, mas também o consideramos pertinente aos professores que preparam seus alunos para provas de escolha múltipla, seja de vestibulares ou concursos públicos em geral.

As questões e o modelo de leitura da prova de língua inglesa do vestibular da UFRGS

O ponto de partida deste estudo foi a elaboração de um questionário e a aplicação do mesmo a alunos concluintes do ensino médio em 1999, percebendo-se a partir dele que os alunos consideravam a prova de vestibular de língua inglesa como difícil. Assim, surgiu a necessidade de avaliar a prova de língua inglesa da Universidade Federal do Rio Grande do Sul quanto ao grau de proficiência exigido do candidato e quanto ao modelo de leitura subjacente a essa prova. Para tal foram analisadas as provas de vestibular dos anos de 1992, 1994, 1996, 1998 e 2000, quanto ao tipo de tarefas e a tipologia textual que apresentam, apresentando os dados coletados através de categorias pré-determinadas. Após a coleta dos dados pôde-se levantar algumas conclusões: a) as questões de compreensão, vocabulário e gramática, embora não tenham sofrido alterações na sua distribuição com o correr dos anos, têm privilegiado principalmente as questões que enfocam mais os recursos lingüísticos necessários para a leitura do texto; b) a proposta do manual do candidato da UFRGS está em contraste com o que se pôde observar na análise das provas, visto que aponta para um modelo interativo de leitura, enquanto na prática enfatiza um modelo autônomo de leitura, onde o sentido do texto se encerra no texto propriamente dito, uma vez que o leitor não conta com recursos extralingüísticos que possam ajudá-lo a construir o sentido do texto; c) o nível de proficiência, no que diz respeito às questões, vocabulário e tipologia textual, pode ser considerado de nível avançado +, de acordo com os critérios propostos pela ACTFL, não só pela profundidade mas também pela abstração encontradas nos textos analisados.