1,385 research outputs found
Meios de vida, estratégias econômicas e dependência de recursos naturais em comunidades nas áreas de ocorrência de babaçuais.
A multiplicidade de estratégias econômicas adotadas em comunidades tradicionais e de agricultores familiares demonstra interações dinâmicas visando aumentar a resiliência de grupos vulneráveis. Neste artigo focalizamos situações em que produtos derivados da palmeira babaçu constituem fontes relevantes de sustento para comunidades no Maranhão. A renda média anual de 168 famílias em três comunidades atingiu R$7.234,00. Transferências sociais e trabalho assalariado representaram mais da metade da renda reportada pelos domicílios, enquanto produtos derivados do babaçu atingiram 12,5% da renda anual. Examinamos padrões de associação entre indicadores de renda, bem-estar, e dependência de atividades extrativas ou agrícolas. Adotamos uma tipologia de domicílios conforme estratégias econômicas, sendo a dependência definida por proporções relativas da renda agrícola e florestal/extrativa. A análise de variância indica diferenças estatisticamente significativas apenas entre domicílios com maior dependência de transferências sociais e trabalho assalariado, cuja renda anual é superior aos de orientação extrativista e diversificados
Análise de relevância da agricultura familiar no estado do Pará.
Este trabalho identificou municípios paraenses nos quais a agricultura familiar apresenta-se com relevância e potencial de desenvolvimento contrastante. Examinando-se as 12 Regiões de Integração (RI) definidas pelo governo do Estado do Pará, foram gerados rankings dos municípios em cada RI para a relevância da agricultura familiar conforme duas variáveis: a porcentagem da área municipal em estabelecimentos da agricultura familiar, e a produção da cultura da mandioca. Constatou-se que a importância da agricultura familiar não deve ser definida apenas a partir de uma variável. Utilizando-se estas duas variáveis para analisar a relevância do segmento, em 24 possíveis situações (12 RI, municípios com maior e menor índice para cada variável) houve coincidência entre rankings de municípios em apenas uma das situações
Evaluation of a technique to generate artificially thickened boundary layers in supersonic and hypersonic flows
The feasibility of using a contoured honeycomb model to generate a thick boundary layer in high-speed, compressible flow was investigated. The contour of the honeycomb was tailored to selectively remove momentum in a minimum of streamwise distance to create an artificially thickened turbulent boundary layer. Three wind tunnel experiments were conducted to verify the concept. Results indicate that this technique is a viable concept, especially for high-speed inlet testing applications. In addition, the compactness of the honeycomb boundary layer simulator allows relatively easy integration into existing wind tunnel model hardware
Tooth replacement in Manidens condorensis: baseline study to address the replacement pattern in dentitions of early ornithischians
Dental replacement in Heterodontosauridae has been debated over the last five decades primarily on indirect evidence, such as the development of wear facets and the position of erupted teeth. Direct observation of unerupted teeth provides unambiguous data for understanding tooth replacement but this has been done only for Heterodontosaurus and Fruitadens. This study addresses dental replacement in Manidens condorensis based on the positioning of functional and replacement teeth using microcomputed tomography data, differential wear along the dentition and the differences in labiolingual/apicobasal level of functional teeth. Dental replacement in Manidens condorensis was continuous in an anterior‐to‐posterior wave pattern, with asynchronous tooth eruption and the addition of new teeth posteriorly to the toothrow during ontogeny. Manidens shows the first evidence of dental replacement for the large dentary caniniform in Heterodontosauridae, which possibly had replacement timing distinct from the cheek dentition. Newly erupted teeth imbricate in a mesial cavity–distal crown base relationship during eruption, so that imbrication of the midposterior dentition remains unaltered during tooth replacement. The presence/absence of a small caniniform tooth in the D3 position of several specimens suggests possible intraspecific dimorphism in Manidens. On longitudinal sections of isolated crowns the histological features such as Howship's lacunae and odontoclast spaces are similar in size to extant reptiles. The differential wear decreasing posteriorly and hypothetical Z‐spacing below 2.3 in Manidens are similar to basal ornithischians. Tooth replacement in Heterodontosauridae (and other early ornithischians) provides key information for understanding the dynamics of jaw function and craniomandibular specialization to herbivory
Ontogenetic plasticity in cranial morphology is associated with a change in the food processing behavior in Alpine newts
Background
The feeding apparatus of salamanders consists mainly of the cranium, mandible, teeth, hyobranchial apparatus and the muscles of the cranial region. The morphology of the feeding apparatus in turn determines the boundary conditions for possible food processing (i.e., intraoral mechanical reduction) mechanisms. However, the morphology of the feeding apparatus changes substantially during metamorphosis, prompting the hypothesis that larvae might use a different food processing mechanism than post-metamorphic adults. Salamandrid newts with facultative metamorphosis are suitable for testing this hypothesis as adults with divergent feeding apparatus morphologies often coexist in the same population, share similar body sizes, and feed on overlapping prey spectra.
Methods
We use high-speed videography to quantify the in vivo movements of key anatomical elements during food processing in paedomorphic and metamorphic Alpine newts (Ichthyosaura alpestris). Additionally, we use micro-computed tomography (μCT) to analyze morphological differences in the feeding apparatus of paedomorphic and metamorphic Alpine newts and sort them into late-larval, mid-metamorphic and post-metamorphic morphotypes.
Results
Late-larval, mid-metamorphic and post-metamorphic individuals exhibited clear morphological differences in their feeding apparatus. Regardless of the paedomorphic state being externally evident, paedomorphic specimens can conceal different morphotypes (i.e., late-larval and mid-metamorphic morphotypes). Though feeding on the same prey under the same (aquatic) condition, food processing kinematics differed between late-larval, mid-metamorphic and post-metamorphic morphotypes.
Conclusions
The food processing mechanism in the Alpine newt changes along with morphology of the feeding apparatus during ontogeny, from a mandible-based to a tongue-based processing mechanism as the changing morphology of the mandible prevents chewing and the tongue allows enhanced protraction. These results could indicate that early tetrapods, in analogy to salamanders, may have developed new feeding mechanisms in their aquatic environment and that these functional innovations may have later paved the way for terrestrial feeding mechanisms
Development of a laser-induced heat flux technique for measurement of convective heat transfer coefficients in a supersonic flowfield
A technique is developed to measure the local convective heat transfer coefficient on a model surface in a supersonic flow field. The technique uses a laser to apply a discrete local heat flux at the model test surface, and an infrared camera system determines the local temperature distribution due to heating. From this temperature distribution and an analysis of the heating process, a local convective heat transfer coefficient is determined. The technique was used to measure the load surface convective heat transfer coefficient distribution on a flat plate at nominal Mach numbers of 2.5, 3.0, 3.5, and 4.0. The flat plate boundary layer initially was laminar and became transitional in the measurement region. The experimental results agreed reasonably well with theoretical predictions of convective heat transfer of flat plate laminar boundary layers. The results indicate that this non-intrusive optical measurement technique has the potential to obtain high quality surface convective heat transfer measurements in high speed flowfields
Movimentos sociais de mulheres e modos de vida em transformação: revendo a questão dos recursos de uso comum em comunidades tradicionais.
O objetivo deste artigo é analisar comparativamente dois movimentos sociais liderados por mulheres que praticam o extrativismo de recursos de uso comum: o movimento das mulheres quebradeiras de coco babaçu e o das catadoras de mangaba. A pesquisa foi realizada com uma abordagem qualitativa, através de entrevistas abertas e em grupos de enfoque, além de observações direta e participante, nos lugares de trabalho e em mobilizações e eventos. Os principais resultados mostram como aos enfrentamentos nos seus respectivos campos de trabalho, juntam-se as recentes batalhas nos campos jurídicos e políticos, demandando novos aportes teóricos dos analistas e novas competências dos movimentos sociais, além da revisão do conceito de recurso de uso comum
The psycholinguistic and affective structure of words conveying pain
Despite the flourishing research on the relationships between affect and language, the characteristics of pain-related words, a specific type of negative words, have never been systematically investigated from a psycholinguistic and emotional perspective, despite their psychological relevance. This study offers psycholinguistic, affective, and pain-related norms for words expressing physical and social pain. This may provide a useful tool for the selection of stimulus materials in future studies on negative emotions and/or pain. We explored the relationships between psycholinguistic, affective, and pain-related properties of 512 Italian words (nouns, adjectives, and verbs) conveying physical and social pain by asking 1020 Italian participants to provide ratings of Familiarity, Age of Acquisition, Imageability, Concreteness, Context Availability, Valence, Arousal, Pain-Relatedness, Intensity, and Unpleasantness. We also collected data concerning Length, Written Frequency (Subtlex-IT), N-Size, Orthographic Levenshtein Distance 20, Neighbor Mean Frequency, and Neighbor Maximum Frequency of each word. Interestingly, the words expressing social pain were rated as more negative, arousing, pain-related, and conveying more intense and unpleasant experiences than the words conveying physical pain
Role of Visual Dysfunction in Postural Control in Children With Cerebral Palsy
Introduction: Deficient postural control is one of the key problems in cerebral palsy (CP). Little, however, is known about the specific nature of postural problems of children with CP, nor of the relation between abnormal posture and dysfunction of the visual system. Aim of the study: To provide additional information on the association of abnormalities in postural control and visual dysfunction of the anterior or posterior part of the visual system. Methods: Data resulting from ophthalmologic, orthoptic, neurological, neuro-radiological, and ethological investigations of more than 313 neurologically impaired children were retrospectively analyzed. Results: Abnormal postural control related to ocular and ocular motor disorders consisted of anomalous head control and subsequent abnormal head posture and torticollis. The abnormal postural control related to retrochiasmatical damage of the visual system consisted of a torticollis combined with adjustment of the upper part of the body, as if at the same time adapting to a combination of defects and optimizing residual visual functions. Conclusion: Visual dysfunctions play a distinct role in the postural control of children with CP
- …