Diferenças no padrão da atividade alelopática em espécies da família Leguminosae

As inúmeras espécies de plantas que compõem a floresta amazônica podem representar excelente alternativa para fazer frente ao desafio de desenvolver a agricultura conforme as exigências da sociedade. Neste trabalho, procurou-se determinar e caracterizar o padrão de atividade alelopática em espécies da família Leguminosae, em função de variações de espécies, fonte de extratos e sensibilidade da planta receptora. Bioensaios de germinação de sementes e alongamento da radícula e do hipocótilo foram desenvolvidos em condições controladas. Os resultados indicam que as espécies estudadas não apresentaram padrão semelhante no tocante aos efeitos potenciais alelopáticos, havendo, entretanto, hierarquização no tocante à intensidade dos efeitos globais, sendo o potencial alelopático inibitório mais amplo e efetivo nas espécies Bauhinia guianensis, Bowdichia virgiloides, Parkia pendula e Platimenia reticulata. O potencial alelopático foi efetivo e mais restrito em Bauhinia macrostachya. O fator fração das plantas revelou diferenciação no padrão de atividade: para a maioria das espécies, as folhas foram a principal fonte de aleloquímicos, e para Bauhinia macrostachya e Inga edulis, a raiz. Em termos de padrão de respostas das espécies receptoras, o alongamento da radícula é mais sensível aos efeitos dos extratos, ficando o alongamento do hipocótilo como o de menor sensibilidade. Os efeitos dos extratos foram mais intensos sobre Mimosa pudica. Esses resultados também atribuem à floresta amazônica importância como fonte de compostos químicos de interesse para o homem, o que, em si, justifica sua preservação.

Organização das comunidades infestantes de plantas daninhas na cultura da cana-de-açúcar em agrupamentos-padrão

O objetivo deste estudo foi avaliar a possibilidade de agrupar talhões de cana-de-açúcar colhida mecanicamente e sem queima prévia da palha na região de Ribeirão Preto-SP, de acordo com o potencial de infestação de plantas daninhas, por meio de análise de agrupamento por método hierárquico e outras técnicas de análise multivariada, utilizando como variável o índice de infestação relativa atribuído por avaliações visuais, em duas etapas. A primeira contemplou 20 talhões de cana-planta com ciclo de 18 meses; essas áreas foram utilizadas para comparação de dois métodos de estimativa da composição específica da flora daninha: análise fitossociológica e por meio da porcentagem visual de cobertura geral (CG) e específica (CE). A segunda etapa consistiu no levantamento da composição específica da comunidade de plantas daninhas em 189 talhões, em áreas de cana-soca colhidas durante a safra de 2008, incluindo nesses talhões apenas CG e CE. Com as informações sobre os levantamentos da comunidade infestante foi construído um banco de dados, posteriormente submetido a análises exploratórias por técnicas de estatística multivariada. Para as principais espécies dentro dos talhões, que foram DIGNU, ARACH, IPOHF, MRRCI e IPOQU, seguidas de CYPRO, ELEIN e EPHHS, foram verificados 75% de coincidências de resultados entre os dois métodos de avaliação. Também notou-se que as avaliações visuais de porcentagem de cobertura das espécies podem substituir, para fins de praticidade, agilidade e aplicabilidade, as avaliações fitossociológicas, uma vez que proporcionaram boa capacidade de detecção das principais plantas daninhas dentro de cada talhão. As técnicas de estatística multivariada demonstraram que os talhões podem ser agrupados de acordo com semelhanças na intensidade da infestação e na composição específica.

Epidemiology, management and outcome of facial injuries

Dental injuries are common and the incidence of maxillofacial injuries has increased over the recent decades in Finland. Accidental injuries are the global leading cause of death among children over the age of one year and among adults under the age of 40 globally. Significant resources and costs are needed for the treatment of these patients. The prevention is the most economical way to reduce trauma rates and costs. For the prevention it is crucial to know the prevalences, incidences and risk factors related to injuries. To improve the quality of treatment, it is essential to explore the causes, trauma mechanisms and management of trauma. The above mentioned was the aim of this thesis. With a large epidemiological cohort study (5737 participants) it was possible to estimate lifetime prevalence of and risk factors for dental trauma in general population (Study I). The prevalence of dental fractures was 43% and the prevalence of dental luxations and avulsions was 14%. Male gender, a history of previous non-dental injuries, mental distress, overweight and high alcohol consumption were positively associated with the occurrence of dental injuries Study II was conducted to explore the differences in type and multiplicity of mandibular fractures in three different countries (Canada, Finland and Kuwait). This retrospective study showed that the differences in mandibular fracture multiplicity and location are based on different etiologies and demographic patterns. This data can be exploited for planning of measures to prevent traumatic facial fractures. The etiology, management and outcome of 63 pediatric skull base fracture (Study III) and 20 pediatric frontobasal fracture patients (Study IV) were explored. These retrospective studies showed that, both skull base fracture and frontobasa fracture are rare injuries in childhood and although intracranial injuries and morbidity are frequent, permanent neurological or neuropsychological deficits are infrequent. A systematic algorithm (Study V) for computer tomography (CT) image review was aimed at clinicians and radiologists to improve the assessment of patients with complex upper midface and cranial base trauma. The cohort study was cross sectional and data was collected in the Turku and Oulu University Hospitals. A novel image-reviewing algorithm was created to enhance the specificity of CT for the diagnosis of frontobasal fractures. The study showed that an image-viewing algorithm standardizes the frontobasal trauma detection procedure and leads to better control and assessment. The purpose of the retrospective subcranial craniotomy study (VI) was to review the types of frontobasal fractures and their management, complications and outcome when the fracture is approached subcranially. The subcranial approach appears to be successful and have a reasonably low complication rate. It may be recommended as the technique of choice in multiple and the most complicated frontal base fractures where the endoscopic endonasal approach is not feasible.

Efeito do fotoperíodo no crescimento e no padrão de acúmulo de frutanos em plantas aclimatizadas de Gomphrena macrocephala St.-Hil. (Amaranthaceae)

Gomphrena macrocephala é uma espécie herbácea perene, nativa do cerrado brasileiro, que apresenta propriedades medicinais e potencial ornamental. Como outras espécies do cerrado, apresenta fases fenológicas bem definidas. A espécie tem sido estudada em função do acúmulo de carboidratos do tipo frutano em sua raiz tuberosa, cujo padrão de variação está relacionado com as fases fenológicas. O presente estudo utilizou plantas micropropagadas e aclimatizadas, com o objetivo de investigar a presença de frutanos em raízes tuberosas, além de verificar se as condições fotoperiódicas interferem no crescimento, no comportamento fenológico e no acúmulo de frutanos dessas plantas. Dias curtos (8 h) proporcionaram menor crescimento vegetativo, induziram o aparecimento de caracteres de senescência e acúmulo de polissacarídeos, como já descrito para plantas em início de dormência. Dias longos (12 e 16 h), no entanto, estimularam maior desenvolvimento da parte aérea e resultaram em menor conteúdo de frutanos, semelhante ao observado em plantas em fase de crescimento vegetativo.

Comparação do padrão da distribuição espacial em escalas diferentes de espécies nativas do cerrado, em Brasília, DF

O padrão de agrupamento espacial de três espécies arbóreas, Caryocar brasiliense, Pterodon pubescens e Sclerolobium paniculatum, e duas espécies de palmeiras, Syagrus comosa e S. flexuosa, nativas do cerrado, foi investigado usando três métodos de variância entre parcelas. Os dados foram coletados em uma área de cerrado sensu strictu da Fazenda Água Limpa da Universidade de Brasília, em Brasília, DF, em 128 parcelas contíguas de 5 x 8 m cada. Em cada parcela, foram procurados todos os indivíduos das espécies, anotando o número encontrado e suas alturas. Os dados foram tabelados e analisados usando as técnicas de variância entre blocos de parcelas (BQV), variância móvel entre blocos de parcelas (TTLQV) e variância entre parcelas pareadas (PQV), tanto para todos os indivíduos encontrados quanto para somente os indivíduos lenhosos maiores do que 130 cm em altura. O número total de indivíduos encontrado foi 138 para C. brasiliense, 34 para P. pubescens, 82 para S. paniculatum, oito para S. comosa e 36 para S. flexuosa. Todas as espécies apresentaram um padrão agrupado de distribuição espacial em pelo menos uma das metodologias e três das cinco espécies tiveram resultados semelhantes em todos os métodos. O padrão para C. brasiliense foi semelhante ao encontrado para esta mesma espécie em outra região do cerrado, utilizando a mesma metodologia, com uma distância de aproximadamente 350 m entre grupos.

Padrão de deposição de sementes e sobrevivência de sementes e plântulas de duas espécies de Myrtaceae na Mata Atlântica

Embora aves e macacos freqüentemente se alimentem dos mesmos frutos, a qualidade da dispersão de sementes produzida por estes animais pode diferir em vários aspectos. Um desses aspectos é o padrão de deposição de sementes ou o modo como as sementes são depositadas no ambiente; aves tendem a depositar sementes isoladas enquanto os macacos as depositam agrupadas. Neste trabalho investigou-se, para duas espécies de Myrtaceae da Mata Atlântica (Gomidesia anacardiifolia e Marlierea obscura) cujos frutos possuem características ornitocóricas, mas que na natureza são comidos por aves e macacos, a sobrevivência de sementes e plântulas experimentalmente arranjadas de modo a simular os padrões de deposição de sementes produzidos por estes dispersores. Ao final de seis meses de acompanhamento, os resultados indicaram diferenças entre os tratamentos isolado e agrupado na sobrevivência de sementes e plântulas consideradas separadamente. A magnitude e direção de tais diferenças, entretanto, variaram interespecificamente. Ao analisar as duas fases (semente e plântula) em conjunto, concluiu-se que, para ambas as espécies de plantas, o padrão de deposição isolado deve produzir um balanço entre número de sementes dispersadas e número de plântulas estabelecidas mais favorável que o padrão agrupado. Isto sugere que, em comparação com macacos, as aves otimizam o esforço reprodutivo das plantas pesquisadas.

Desenvolvimento reprodutivo de Hyptis suaveolens (L.) Poit.: relação entre fotoperíodo, densidade celular meristemática e padrão de expressão de um ortólogo putativo do gene LEAFY de arabidopsis

Hyptis suaveolens (L.) Poit. é uma planta da família Lamiaceae, considerada uma espécie tipicamente invasora. Entretanto, é produtora de óleo essencial, ao qual várias atividades biológicas são atribuídas. Informações sobre o desenvolvimento reprodutivo nesta espécie seriam úteis à elucidação de mecanismos adaptativos relacionados à indução floral em espécies invasoras, e ao incremento na produção de óleo essencial, devido sua preponderância nas flores. Assim, aqui caracterizamos alguns aspectos do desenvolvimento reprodutivo em Hyptis suaveolens. Plantas de H. suaveolens foram submetidas a dois tratamentos fotoperiódicos (fotoperíodo natural de Alfenas e fotoperíodo mínimo de 16 h) para amostragem de ápices aéreos vegetativos e florais em cinco datas. Nestes materiais botânicos foram realizadas análises anatômicas, ensaios de hibridização in situ para detecção dos transcritos de um ortólogo putativo de LEAFY e microscopia eletrônica de varredura. Hyptis suaveolens é uma planta de dias curtos, com fotoperíodo crítico em torno de 13 h. A atividade meristemática vegetativa ou floral pôde ser evidenciada pela densidade celular. O ortólogo putativo de LEAFY em H. suaveolens exibiu o padrão de expressão clássico descrito em Antirrhinum e Arabidopsis, mas também foi expresso em ápices vegetativos de plantas cultivadas sob fotoperíodo natural, independente da época de amostragem. Entretanto, não foi expresso em meristemas vegetativos de plantas cultivadas em fotoperíodo mínimo de 16 h. Estes resultados sugerem uma expressão basal de LEAFY em meristemas vegetativos de H. suaveolens, que é fortemente reduzida sob fotoperíodo mínimo de 16 h ou incrementada em fotoperíodos inferiores a 13 h, atingindo níveis satisfatórios à determinação floral.

Deep generative models for facial keypoints detection

A new area of machine learning research called deep learning, has moved machine learning closer to one of its original goals: artificial intelligence and general learning algorithm. The key idea is to pretrain models in completely unsupervised way and finally they can be fine-tuned for the task at hand using supervised learning. In this thesis, a general introduction to deep learning models and algorithms are given and these methods are applied to facial keypoints detection. The task is to predict the positions of 15 keypoints on grayscale face images. Each predicted keypoint is specified by an (x,y) real-valued pair in the space of pixel indices. In experiments, we pretrained deep belief networks (DBN) and finally performed a discriminative fine-tuning. We varied the depth and size of an architecture. We tested both deterministic and sampled hidden activations and the effect of additional unlabeled data on pretraining. The experimental results show that our model provides better results than publicly available benchmarks for the dataset.

Avaliação do padrão coliformes a 45ºC e comparação da eficiência das técnicas dos tubos múltiplos e Petrifilm EC na detecção de coliformes totais e Escherichia coli em alimentos

Coliformes fecais são definidos como coliformes capazes de fermentar a lactose com produção de gás em 48 h a 45ºC. Escherichia coli, juntamente com algumas cepas de Enterobacter e Klebsiella, podem apresentar essas características. Entretanto, apenas a presença de Escherichia coli em alimentos indica contaminação fecal por ser encontrada em grande quantidade no trato gastrointestinal do homem e animais de sangue quente, não sendo isolada normalmente em outros nichos. A denominação clássica de coliformes fecais foi alterada para coliformes a 45ºC, na Resolução nº 12 da Agência Nacional de Vigilância Sanitária. O objetivo deste trabalho foi avaliar a presença de E. coli entre os coliformes a 45ºC e comparar a eficiência das técnicas dos tubos múltiplos e Petrifilm EC na detecção de coliformes totais e E. coli em queijo Minas, lingüiça frescal, hortaliças e fubá. Petrifilm EC mostrou-se mais sensível na detecção de E. coli em relação ao método de tubos múltiplos, o qual apresentou resultados falso-negativos ou contagens subestimadas de E. coli, principalmente para amostras de alimentos de origem animal. Petrifilm EC foi o mais eficiente e prático, sendo um método alternativo adequado para a enumeração de coliformes totais e E. coli em alimentos.

As duas vias do princípio das vantagens comparativas de David Ricardo e o padrão-ouro: um ensaio crítico

This article critically resumes Ricardo's principle of comparative advantages pointing out internal coherence problems that have been neglected by the specialized literature. First, long-lasting disequilibria observed in the balance of trade seem incompatible with the idea that these disequilibria are caused by technical advances that change relative prices. Second, comparative advantages do not seem to work in an economy with a universally accepted commodity-money. Finally, the contradiction between the gold standard mechanisms, ruled by Smith's "Law of Reflux", and the quantitative theory of money, which is a necessary condition for the "second way" of the theory of comparative advantages.

Sensitivity to differences between posed and genuine facial expressions : are children easily fooled? /

Adults and children can discriminate various emotional expressions, although there is limited research on sensitivity to the differences between posed and genuine expressions. Adults have shown implicit sensitivity to the difference between posed and genuine happy smiles in that they evaluate T-shirts paired with genuine smiles more favorably than T-shirts paired with posed smiles or neutral expressions (Peace, Miles, & Johnston, 2006). Adults also have shown some explicit sensitivity to posed versus genuine expressions; they are more likely to say that a model i?,feeling happy if the expression is genuine than posed. Nonetheless they are duped by posed expressions about 50% of the time (Miles, & Johnston, in press). There has been no published study to date in which researchers report whether children's evaluation of items varies with expression and there is little research investigating children's sensitivity to the veracity of facial expressions. In the present study the same face stimuli were used as in two previous studies (Miles & Johnston, in press; Peace et al., 2006). The first question to be addressed was whether adults and 7-year-olds have a cognitive understanding of the differences between posed and genuine happiness {scenario task). They evaluated the feelings of children who expressed gratitude for a present that they did or did not want. Results indicated that all participants had a fundamental understanding of the difference between real and posed happiness. The second question involved adults' and children's implicit sensitivity to the veracity of posed and genuine smiles. Participants rated and ranked beach balls paired with faces showing posed smiles, genuine smiles, and neutral expressions. Adults ranked.but did not rate beach balls paired with genuine smiles more favorably than beach balls paired with posed smiles. Children did not demonstrate implicit sensitivity as their ratings and rankings of beach balls did not vary with expressions; they did not even rank beach balls paired with genuine expressions higher than beach balls paired with neutral expressions. In the explicit (show/feel) task, faces were presented without the beach balls and participants were first asked whether each face was showing happy and then whether each face wasfeeling happy. There were also two matching trials that presented two faces at once; participants had to indicate which person was actuallyfeeling happy. In the show condition both adults and 7-year-olds were very accurate on genuine and neutral expressions but made some errors on posed smiles. Adults were fooled about 50% of the time by posed smiles in thefeel condition (i.e., they were likely to say that a model posing happy was really feeling happy) and children were even less accurate, although they showed weak sensitivity to posed versus genuine expressions. Future research should test an older age group of children to determine when explicit sensitivity to posed versus genuine facial expressions becomes adult-like and modify the ranking task to explore the influence of facial expressions on object evaluations.

Electrophysiological and behavioural correlates of facial identity and expression perception deficits following a closed head injury /

A large variety of social signals, such as facial expression and body language, are conveyed in everyday interactions and an accurate perception and interpretation of these social cues is necessary in order for reciprocal social interactions to take place successfully and efficiently. The present study was conducted to determine whether impairments in social functioning that are commonly observed following a closed head injury, could at least be partially attributable to disruption in the ability to appreciate social cues. More specifically, an attempt was made to determine whether face processing deficits following a closed head injury (CHI) coincide with changes in electrophysiological responsivity to the presentation of facial stimuli. A number of event-related potentials (ERPs) that have been linked specifically to various aspects of visual processing were examined. These included the N170, an index of structural encoding ability, the N400, an index of the ability to detect differences in serially presented stimuli, and the Late Positivity (LP), an index of the sensitivity to affective content in visually-presented stimuli. Electrophysiological responses were recorded while participants with and without a closed head injury were presented with pairs of faces delivered in a rapid sequence and asked to compare them on the basis of whether they matched with respect to identity or emotion. Other behavioural measures of identity and emotion recognition were also employed, along with a small battery of standard neuropsychological tests used to determine general levels of cognitive impairment. Participants in the CHI group were impaired in a number of cognitive domains that are commonly affected following a brain injury. These impairments included reduced efficiency in various aspects of encoding verbal information into memory, general slower rate of information processing, decreased sensitivity to smell, and greater difficulty in the regulation of emotion and a limited awareness of this impairment. Impairments in face and emotion processing were clearly evident in the CHI group. However, despite these impairments in face processing, there were no significant differences between groups in the electrophysiological components examined. The only exception was a trend indicating delayed N170 peak latencies in the CHI group (p = .09), which may reflect inefficient structural encoding processes. In addition, group differences were noted in the region of the N100, thought to reflect very early selective attention. It is possible, then, that facial expression and identity processing deficits following CHI are secondary to (or exacerbated by) an underlying disruption of very early attentional processes. Alternately the difficulty may arise in the later cognitive stages involved in the interpretation of the relevant visual information. However, the present data do not allow these alternatives to be distinguished. Nonetheless, it was clearly evident that individuals with CHI are more likely than controls to make face processing errors, particularly for the more difficult to discriminate negative emotions. Those working with individuals who have sustained a head injury should be alerted to this potential source of social monitoring difficulties which is often observed as part of the sequelae following a CHI.

The influence of emotional body posture on adults' and 8-year-olds' perception facial expressions

The present set of experiments was designed to investigate the development of children's sensitivity of facial expressions observed within emotional contexts. Past research investigating both adults' and children's perception of facial expressions has been limited primarily to the presentation of isolated faces. During daily social interactions, however, facial expressions are encountered within contexts conveying emotions (e.g., background scenes, body postures, gestures). Recently, research has shown that adults' perception of facial expressions is influenced by these contexts. When emotional faces are shown in incongruent contexts (e.g., when an angry face is presented in a context depicting fear) adults' accuracy decreases and their reaction times increase (e.g., Meeren et a1. 2005). To examine the influence of emotional body postures on children's perception of facial expressions, in each of the experiments in the current study adults and 8-year-old children made two-alternative forced choice decisions about facial expressions presented in congruent (e.g., a face displayed sadness on a body displaying sadness) and incongruent (e.g., a face displaying fear on a body displaying sadness) contexts. Consistent with previous studies, a congruency effect (better performance on congruent than incongruent trials) was found for both adults and 8-year-olds when the emotions displayed by the face and body were similar to each other (e.g., fear and sad, Experiment l a ) ; the influence of context was greater for 8-year-olds than adults for these similar expressions. To further investigate why the congruency effect was larger for children than adults in Experiment 1 a, Experiment 1 b was conducted to examine if increased task difficulty would increase the magnitude of adults' congruency effects. Adults were presented with subtle facial and despite successfully increasing task difficulty the magnitude of the. congruency effect did not increase suggesting that the difference between children's and adults' congruency effects in Experiment l a cannot be explained by 8-year-olds finding the task difficult. In contrast, congruency effects were not found when the expressions displayed by the face and body were dissimilar (e.g., sad and happy, see Experiment 2). The results of the current set of studies are examined with respect to the Dimensional theory and the Emotional Seed model and the developmental timeline of children's sensitivity to facial expressions. A secondary aim of the series of studies was to examine one possible mechanism underlying congruency effe cts-holistic processing. To examine the influence of holistic processing, participants completed both aligned trials and misaligned trials in which the faces were detached from the body (designed to disrupt holistic processing). Based on the principles of holistic face processing we predicted that participants would benefit from misalignment of the face and body stimuli on incongruent trials but not on congruent trials. Collectively, our results provide some evidence that both adults and children may process emotional faces and bodies holistically. Consistent with the pattern of results for congruency effects, the magnitude of the effect of misalignment varied with the similarity between emotions. Future research is required to further investigate whether or not facial expressions and emotions conveyed by the body are perceived holistically.

Sir Isaac Brock Facial Reconstruction Project, n.d.

Christian Cardell Corbet, a descendant of Guernsey, Channel Islands, was born in 1966 at Pickering Beach on Lake Ontario. He developed his talents as a landscape artist and at the young age of 14 he began his informal education in commercial signage from his paternal grandfather. He studied at the University of Guelph and McMaster University Anatomy Laboratory. Corbet traveled to England where he began to experiment more in abstraction and non-objective work. In 1995, he presented a portrait of HM Queen Elizabeth the Queen Mother at Clarence House. This brought his career to an international level. He also creates two-dimensional works and has received acclaim for his bronze art medallions. He has gained international recognition as a Forensic Artist working as Artist in Residence for the University of Western Ontario. He does facial reconstructions for special assignments. These original drawings relate to a sculpted medallion of Brock which was authorized by Sir Geoffrey Rowland, Bailiff, Guernsey, Channel Islands and Minister of Education of the States of Guernsey. This is the first time in known recorded history that a forensic analysis and sculpture has been created to accurately depict the facial likeness of Sir Isaac Brock. This project has been established to mark the 2012 anniversary of the death of Brock.