Tecendo uma virtuosa "colcha de retalhos": a constituição e interpretação de um corpus lingüístico num estudo sobre reflexividade e articulação empreendedora

Este artigo apresenta a etapa fundamental de um processo investigativo maior, a constituição e a análise interpretativa de um corpus lingüístico capaz de propiciar avanço na direção apontada em etapa prévia - quando focos e questões de interesse foram consolidados - de um estudo sobre reflexividade e articulação empreendedora. Daí essa "colcha" aqui tecida ser denominada "virtuosa", ou seja, algo capaz (que tem a virtude) de "produzir efeitos". Pretende-se trazer à tona esse processo de entrelaçamento de evidências oriundas das mais diversas fontes e a natural construção desse corpus e das interpretações, à luz do aporte teórico dos autores. Como foi tecido esse corpus? Qual foi sua importância para o avanço deste estudo? Estas são as principais questões. Como resultado, o referido corpus demonstrou ter grande utilidade para acesso e agrupamento de evidências no "caso ilustrativo", e a interpretação, à luz do aporte teórico, de questões importantes (previamente elencadas) para o fenômeno central em estudo: a "articulação empreendedora de caráter reflexivo", por meio das evidências encontradas no caso.

Pesquisa disciplinar do corpus documental das teses de doutorado do PPGCI-IBICT/UFRJ: aplicando princípios e categorias para estudo interdisciplinar da ciência da informação no Brasil

A partir do histórico da ciência da informação no Brasil, realizou-se estudo visando a investigar, mediante princípios e categorias, a relação das disciplinas com a ciência da informação. O modelo aplicado dividiu o corpus de 58 teses em três categorias: disciplinas como conjuntos distintos, já que os conceitos e métodos dessa categoria não são suficientes para formalizar um quadro interdisciplinar. A segunda pela interação dos conceitos abordados, com encadeamento das questões colocadas pelas disciplinas na busca de solução para o problema proposto. A terceira remete à integração entre a disciplina e a ciência da informação, apresentando uma linguagem comum. O resultado do estudo visa a contribuir para a criação de um método de pesquisa interdisciplinar para a pós-graduação brasileira.

Morphological features and vascularization study of caprine cyclic corpus luteum

Corpus luteum is a temporary endocrine gland that regulates either the estrous cycle and pregnancy. It presents extreme dependency on the adequate blood supply. This work aims to evaluate goat corpus luteum (CL) vascular density (VD) over the estrous cycle. For that purpose, 20 females were submitted to estrus synchronization/ovulation treatment using a medroxyprogesterone intra-vaginal sponge as well as intramuscular (IM) application of cloprostenol and equine chorionic gonadotrophine (eCG). After sponge removal, estrus was identified at about 72hs. Once treatment was over, female goats were then subdivided into 4 groups (n=5 each) and slaughtered on days 2, 12, 16 and 22 after ovulation (p.o). Ovaries were collected, withdrawn and weighted. CL and ovaries had size and area recorded. Blood samples were collected and the plasma progesterone (P4) was measured through RIA commercial kits. The VD was 24.42±6.66, 36.26±5.61, 8.59±2.2 and 3.97±1.12 vessels/mm² for days 2, 12, 16 and 22 p.o, respectively. Progesterone plasma concentrations were 0.49±0.08, 2.63±0.66, 0.61±0.14 and 0.22±0.04ng/ml for days 2, 12, 16 e 22 p.o, respectively. Studied parameters were affected by the estrous cycle phase. Values greater than 12 p.o were observed. In the present work we observed that ovulation occurred predominantly in the right ovary (70% of the animals), which in turn presented bigger measures than the contra lateral one. There is a meaningful relationship between the weight and size of the ovary and these of CL (r=0.87, r=0.70, respectively, p<0.05). It is possible to conclude that morphology of goat's ovaries and plasma progesterone concentration changed according to estrous cycle stages. We propose these parameters can be used as indicators of CL functional activity.

Follicle and corpus luteum size and vascularity as predictors of fertility at the time of artificial insemination and embryo transfer in beef cattle

Abstract:Two ultrasound based fertility prediction methods were tested prior to embryo transfer (ET) and artificial insemination (AI) in cattle. Female bovines were submitted to estrous synchronization prior to ET and AI. Animals were scanned immediately before ET and AI procedure to target follicle and corpus luteum (CL) size and vascularity. In addition, inseminated animals were also scanned eleven days after insemination to target CL size and vascularity. All data was compared with fertility by using gestational diagnosis 35 days after ovulation. Prior to ET, CL vascularity showed a positive correlation with fertility, and no pregnancy occurred in animals with less than 40% of CL vascularity. Prior to AI and also eleven days after AI, no relationship with fertility was seen in all parameters analyzed (follicle and CL size and vascularity), and contrary, cows with CL vascularity greater than 70% exhibit lower fertility. In inseminated animals, follicle size and vascularity was positive related with CL size and vascularity, as shown by the presence of greater CL size and vascularity originated from follicle with also greater size and vascularity. This is the first time that ultrasound based fertility prediction methods were tested prior to ET and AI and showed an application in ET, but not in AI programs. Further studies are needed including hormone profile evaluation to improve conclusion.

Axonal pathfinding mechanisms at the cortical midline and in the development of the corpus callosum

The corpus callosum is a large fiber tract that connects neurons in the right and left cerebral hemispheres. Agenesis of the corpus callosum (ACC) is associated with a large number of human syndromes but little is known about why ACC occurs. In most cases of ACC, callosal axons are able to grow toward the midline but are unable to cross it, continuing to grow into large swirls of axons known as Probst bundles. This phenotype suggests that in some cases ACC may be due to defects in axonal guidance at the midline. General guidance mechanisms that influence the development of axons include chemoattraction and chemorepulsion, presented by either membrane-bound or diffusible molecules. These molecules are not only expressed by the final target but by intermediate targets along the pathway, and by pioneering axons that act as guides for later arriving axons. Midline glial populations are important intermediate targets for commissural axons in the spinal cord and brain, including the corpus callosum. The role of midline glial populations and pioneering axons in the formation of the corpus callosum are discussed. Finally the differential guidance of the ipsilaterally projecting perforating pathway and the contralaterally projecting corpus callosum is addressed. Development of the corpus callosum involves the coordination of a number of different guidance mechanisms and the probable involvement of a large number of molecules.

One hundred million years of interhemispheric communication: the history of the corpus callosum

Analysis of regional corpus callosum fiber composition reveals that callosal regions connecting primary and secondary sensory areas tend to have higher proportions of coarse-diameter, highly myelinated fibers than callosal regions connecting so-called higher-order areas. This suggests that in primary/secondary sensory areas there are strong timing constraints for interhemispheric communication, which may be related to the process of midline fusion of the two sensory hemifields across the hemispheres. We postulate that the evolutionary origin of the corpus callosum in placental mammals is related to the mechanism of midline fusion in the sensory cortices, which only in mammals receive a topographically organized representation of the sensory surfaces. The early corpus callosum may have also served as a substrate for growth of fibers connecting higher-order areas, which possibly participated in the propagation of neuronal ensembles of synchronized activity between the hemispheres. However, as brains became much larger, the increasingly longer interhemispheric distance may have worked as a constraint for efficient callosal transmission. Callosal fiber composition tends to be quite uniform across species with different brain sizes, suggesting that the delay in callosal transmission is longer in bigger brains. There is only a small subset of large-diameter callosal fibers whose size increases with increasing interhemispheric distance. These limitations in interhemispheric connectivity may have favored the development of brain lateralization in some species like humans. "...if the currently received statements are correct, the appearance of the corpus callosum in the placental mammals is the greatest and most sudden modification exhibited by the brain in the whole series of vertebrated animals..." T.H. Huxley (1).

IUS-LEX-CORPUS: CORPUS MYSTICUM

Sfruttando gli ingenti materiali a disposizione degli studiosi dal 1964 negli archivi, nelle banche dati, nei dizionari e nei lessici d'autore dell'ILIESI-CNR, il contributo considera una serie di momenti nella storia del pensiero, dalla politeía antica al cosmopolitismo moderno, che mettono in risalto le implicazioni filosofiche presenti nella polisemia del trinomio lex-ius-corpus.