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Distinct Aspects (distinct + aspect)
Selected AbstractsAncestors, magic, and exchange in Yolngu doctrines: extensions of the person in time and spaceTHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 3 2006Ian Keen The article draws on the association drawn by Munn between Aboriginal ancestral transformations and the moral order, and the theory of partible persons, in order to re-examine Yolngu doctrines and related practices to do with totemic ancestors and their traces, magic and sorcery, and exchange. It argues that all three broad domains draw on beliefs about intrinsic relations between part and whole, image and object, and the intrinsic powers of bodily substance and spirits of the dead. These domains imply the extension of persons in time and space, and each relates to a rather distinct aspect of the moral-political order. The article shows that the strong dichotomy drawn by Durkheim and his followers between ,religion' and ,magic' obscures the connections between these domains, and neglects the instrumental aspect of Yolngu ancestral doctrines and practices. [source] Defining the glycophenotype of squamous epithelia using plant and mammalian lectins.APMIS, Issue 12 20023-linked N-acetylneuraminic acid in squamous epithelia, Differentiation-dependent expression of, carcinomas, its differential effect on binding of the endogenous lectins galectins- A thorough characterization of the properties of squamous epithelial cells is necessary in order to improve our understanding of the functional aspects of normal development and malignant aberrations. Up to now, studies have focused almost exclusively on monitoring distinct protein markers. With our growing awareness of the coding function of glycan chains of cellular glycoconjugates and their interaction with receptors (lectins) in situ, defining the glycophenotype of these cells has become an important issue. Whereas the commonly applied plant lectins are tools used to map the presence and localization of biochemically defined saccharide epitopes, the introduction of endogenous (mammalian) lectins to this analysis enables us to take the step from monitoring the presence of glycan to understanding the functional implications by revealing ligand properties of the detected epitope for tissue lectin. Thus, in this study we investigated a distinct aspect of glycosylation using plant and mammalian lectins, i.e. the linkage type of sialylation. We first mapped the expression profile of the type of sialylation (,2,3- or ,2,6-linked) by plant lectins. Based on the hypothesis that this factor regulates accessibility of ligands for endogenous lectins we introduced two labeled galectins to this study. Galectin-3 (but not galectin-1) binding was related to cell differentiation in normal adult and developing epithelia, cultured epidermal cells, and carcinomas derived from these epithelia. The presented data suggest that ,2,6-linked N-acetyl- D -neuraminic acid moieties could serve to mask galectin-3-reactive glycoepitopes. As a consequence, monitoring of the linkage type of sialic acid in glycans by plant lectins therefore has implications for the extent of glycan reactivity with endogenous lectins, pointing to a potential function of changes in sialylation type beyond these cell and lectin systems. [source] Differing strategies for forming the arthropod body plan: Lessons from Dpp, Sog and Delta in the fly Drosophila and spider AchaearaneaDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 4 2008Hiroki Oda In the insect Drosophila embryo, establishment of maternal transcription factor gradients, rather than cell,cell interactions, is fundamental to patterning the embryonic axes. In contrast, in the chelicerate spider embryo, cell,cell interactions are thought to play a crucial role in the development of the embryonic axes. A grafting experiment by Holm using spider eggs resulted in duplication of the embryonic axes, similar to the Spemann's organizer experiment using amphibian eggs. Recent work using the house spider Achaearanea tepidariorum has demonstrated that the homologs of decapentaplegic (dpp), short gastrulation (sog) and Delta, which encode a bone morphogenetic protein (BMP)-type ligand, its antagonist and a Notch ligand, respectively, are required in distinct aspects of axis formation. Achaearanea Dpp appears to function as a symmetry-breaking signal, which could account for Holm's results to some extent. Experimental findings concerning Achaearanea sog and Delta have highlighted differences in the mechanisms underlying ventral and posterior development between Drosophila and Achaearanea. Achaearanea ventral patterning essentially depends on sog function, in contrast to the Drosophila patterning mechanism, which is based on the nuclear gradient of Dorsal. Achaearanea posterior (or opisthosomal) patterning relies on the function of the caudal lobe, which develops from cells surrounding the blastopore through progressive activation of Delta-Notch signaling. In this review, we describe the differing strategies for forming the arthropod body plan in the fly and spider, and provide a perspective towards understanding the relationship between the arthropod and vertebrate body plans. [source] High-frequency gamma oscillations coexist with low-frequency gamma oscillations in the rat visual cortex in vitroEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2010Olaleke O. Oke Abstract Synchronization of neuronal activity in the visual cortex at low (30,70 Hz) and high gamma band frequencies (> 70 Hz) has been associated with distinct visual processes, but mechanisms underlying high-frequency gamma oscillations remain unknown. In rat visual cortex slices, kainate and carbachol induce high-frequency gamma oscillations (fast-,; peak frequency , 80 Hz at 37°C) that can coexist with low-frequency gamma oscillations (slow-,; peak frequency , 50 Hz at 37°C) in the same column. Current-source density analysis showed that fast-, was associated with rhythmic current sink-source sequences in layer III and slow-, with rhythmic current sink-source sequences in layer V. Fast-, and slow-, were not phase-locked. Slow-, power fluctuations were unrelated to fast-, power fluctuations, but were modulated by the phase of theta (3,8 Hz) oscillations generated in the deep layers. Fast-, was spatially less coherent than slow-,. Fast-, and slow-, were dependent on ,-aminobutyric acid (GABA)A receptors, ,-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and gap-junctions, their frequencies were reduced by thiopental and were weakly dependent on cycle amplitude. Fast-, and slow-, power were differentially modulated by thiopental and adenosine A1 receptor blockade, and their frequencies were differentially modulated by N -methyl- d -aspartate (NMDA) receptors, GluK1 subunit-containing receptors and persistent sodium currents. Our data indicate that fast-, and slow-, both depend on and are paced by recurrent inhibition, but have distinct pharmacological modulation profiles. The independent co-existence of fast-, and slow-, allows parallel processing of distinct aspects of vision and visual perception. The visual cortex slice provides a novel in vitro model to study cortical high-frequency gamma oscillations. [source] Chemosensory and steroid-responsive regions of the medial amygdala regulate distinct aspects of opposite-sex odor preference in male Syrian hamstersEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2006Pamela M. Maras Abstract In rodent species, such as the Syrian hamster, the expression of sexual preference requires neural integration of social chemosensory signals and steroid hormone cues. Although anatomical data suggest that separate pathways within the nervous system process these two signals, the functional significance of this separation is not well understood. Specifically, within the medial amygdala, the anterior region (MEa) receives input from the olfactory bulbs and other chemosensory areas, whereas the posterodorsal region (MEpd) contains a dense population of steroid receptors and receives less substantial chemosensory input. Consequently, the MEa may subserve a primarily discriminative function, whereas the MEpd may mediate the permissive effects of sex steroids on sexual preference. To test these hypotheses, we measured preference and attraction to female and male odors in males with lesions of either the MEa or MEpd. In Experiment 1, lesions of either region eliminated opposite-sex odor preferences. Importantly, MEpd-lesioned males displayed decreased attraction toward female odors, suggesting decreased sexual motivation. In contrast, MEa-lesioned males displayed high levels of investigation of both male and female odors, suggesting an inability to categorize the relevance of the odor stimuli. In Experiment 2, we verified that both MEa- and MEpd-lesioned males could discriminate between female and male odors, thereby eliminating the possibility that the observed lack of preference reflected a sensory deficit. Taken together, these results suggest that both the MEa and MEpd are critical for the expression of opposite-sex odor preference, although they appear to mediate distinct aspects of this behavior. [source] Distinct kinds of novelty processing differentially increase extracellular dopamine in different brain regionsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2006Elvira De Leonibus Abstract Behaviourally relevant novel stimuli are known to activate the mesocorticolimbic dopaminergic (DAergic) system. In this study we tested the reactivity of this system in response to distinct kinds of novelty processing. Using the in vivo microdialysis technique, we measured extracellular amounts of dopamine (DA) in different DAergic terminal regions during a social learning task in rats. In the first session (40 min) rats were exposed to two never previously encountered juveniles (i.e. unconditional novelty). Afterwards, the animals were divided into three groups: Control group was not exposed to any other stimulus; Discrimination group was exposed to one familiar and one new juvenile (i.e. novel stimulus discrimination); and Recognition group was re-exposed to the two familiar juveniles (i.e. familiarity recognition). In both the medial prefrontal cortex and the nucleus accumbens shell DA increased in response to the first presentation of the juveniles, showing that both structures are involved in processing unconditional social novelty. During the novel stimulus discrimination, we found no change in the prefrontal cortex, although DA increased in the accumbal shell in comparison with the group exposed to two familiar juveniles, showing that the shell is also involved in processing novel social stimulus discrimination. None of the stimuli presented affected DA in the accumbal core. This study provided the original evidence that DA in the various terminal regions is differentially coupled to distinct aspects of novelty processing. [source] Opioids intrinsically inhibit the genesis of mouse cerebellar granule neuron precursors in vitro: differential impact of , and , receptor activation on proliferation and neurite elongationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2000Kurt F. Hauser Abstract Although opioids are known to affect neurogenesis in vivo, it is uncertain the extent to which opioids directly or indirectly affect the proliferation, differentiation or death of neuronal precursors. To address these questions, the intrinsic role of the opioid system in neurogenesis was systematically explored in cerebellar external granular layer (EGL) neuronal precursors isolated from postnatal mice and maintained in vitro. Isolated neuronal precursors expressed proenkephalin-derived peptides, as well as specific , and ,, but negligible ,, opioid receptors. The developmental effects of opioids were highly selective. Morphine-induced , receptor activation inhibited DNA synthesis, while a preferential ,2 -receptor agonist ([d -Ala2]-deltorphin II) or Met-enkephalin, but not the ,1 agonist [d -Pen2, d -Pen5]-enkephalin, inhibited differentiation within the same neuronal population. If similar patterns occur in the developing cerebellum, spatiotemporal differences in endogenous , and , opioid ligand,receptor interactions may coordinate distinct aspects of granule neuron maturation. The data additionally suggest that perinatal exposure to opiate drugs of abuse directly interfere with cerebellar maturation by disrupting normal opioid signalling and inhibiting the proliferation of granule neuron precursors. [source] Workers, worries and welfare states: Social protection and job insecurity in 15 OECD countriesEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 2 2007CHRISTOPHER J. ANDERSON Based on data on people's attitudes toward their job as well as levels of and kinds of social protection collected in 15 OECD countries, it shows that there are distinct manifestations of job insecurity that are affected differently by distinct aspects of social protection programs. While the analysis shows that social protection measures reduce employment insecurity, it also reveals that overall levels welfare state generosity do not have any systematic effect on whether workers feel secure. The article's findings suggest the need to decompose the different components of employment insecurity as well as disaggregate national systems of social protection when examining the impact of welfare states on job insecurity. [source] Pathogen fitness components and genotypes differ in their sensitivity to nutrient and temperature variation in a wild plant,pathogen associationJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2007A.-L. LAINE Abstract Understanding processes maintaining variation in pathogen life-history stages affecting infectivity and reproduction is a key challenge in evolutionary ecology. Models of host,parasite coevolution are based on the assumption that genetic variation for host,parasite interactions is a significant cause of variation in infection, and that variation in environmental conditions does not overwhelm the genetic basis. However, surprisingly little is known about the stability of genotype,genotype interactions under variable environmental conditions. Here, using a naturally occurring plant,pathogen interaction, I tested whether the two distinct aspects of the infection process , infectivity and transmission potential , vary over realistic nutrient and temperature gradients. I show that the initial pathogen infectivity and host resistance responses are robust over the environmental gradients. However, for compatible responses there were striking differences in how different pathogen life-history stages and host and pathogen genotypes responded to environmental variation. For some pathogen genotypes even slight changes in temperature arrested spore production, rendering the developing infection ineffectual. The response of pathogen genotypes to environmental gradients varied in magnitude and even direction, so that their rankings changed across the abiotic gradients. Hence, the variable environment of spatially structured host,parasite interactions may strongly influence the maintenance of polymorphism in pathogen life-history stages governing transmission, whereas evolutionary trajectories of infectivity may be unaffected by the surrounding environment. [source] Communication as a determinant of organizational innovationR & D MANAGEMENT, Issue 1 2000Mika Kivimäki This study of 32 small and medium-sized industrial enterprises explored eight distinct aspects of communication, as appraised by the staff (n = 493), and innovative performance, assessed by two indicators: perceived innovation effectiveness and patent statistics obtained from the Patent Register at the National Board of Patents and Registration of Trademarks. The results showed that intra-organizational aspects of communication, such as encouragement of initiatives and critical evaluation of performance, were associated with both indicators of innovative performance. In addition, a participative climate and interaction between the personnel in R&D, marketing and production were related to perceived innovative effectiveness, whereas interaction with clients and other firms related to the number of patents in the organization. The link between communication and innovation was interdependent with the organizational and staff characteristics including the number of personnel, administrative and R&D intensity, the level of vocational training, and the age distribution of the staff. [source] | |||||||||||||