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Sense Organs (sense + organ)
Selected AbstractsA Critique of Schopenhauer's MetaphysicGERMAN LIFE AND LETTERS, Issue 3 2006G.A. Wells Schopenhauer's metaphysic is not more credible than the systems of his contemporaries Fichte, Schelling and Hegel, all of whom he criticised so severely. But as his writings, unlike theirs, are so lucid, they illustrate very clearly the metaphysician's endeavour to reach knowledge that is immediate and indubitable, not mediated by the sense organs and the brain, as is knowledge of the external world. He argues that ,das Einzige wirklich und unbedingt Gegebene ist das Selbstbewußtsein', which alone can yield ,die letzten und wichtigsten Aufschlüsse über das Wesen der Dinge'. He himself was not religious, but this doctrine has appealed to theologians seeking a basis for their belief that is independent of external (historical) testimony. In this connection, Albert Schweitzer expressly urged a return to the German metaphysical tradition, in particular to Schopenhauer's view of the will as the transcendent reality at the basis of self-consciousness. The present article argues, in the British empirical tradition, that there is really no reason to distinguish self-consciousness and experiences attributable to will from other kinds of experience. The practical distinction is that the idea of self depends largely not on the sensations provided by readily observable senses such as sight and hearing, but on muscular, articular and visceral receptors which constitute a less accessible internal sensorium. [source] Cladistic analysis of Medusozoa and cnidarian evolutionINVERTEBRATE BIOLOGY, Issue 1 2004Antonio C. Marques Abstract. A cladistic analysis of 87 morphological and life history characters of medusozoan cnidarians, rooted with Anthozoa, results in the phylogenetic hypothesis (Anthozoa (Hydrozoa (Scyphozoa (Staurozoa, Cubozoa)))). Staurozoa is a new class of Cnidaria consisting of Stauromedusae and the fossil group Conulatae. Scyphozoa is redefined as including those medusozoans characterized by strobilation and ephyrae (Coronatae, Semaeostomeae, and Rhizostomeae). Within Hydrozoa, Limnomedusae is identified as either the earliest diverging hydrozoan lineage or as the basal group of either Trachylina (Actinulida (Trachymedusae (Narcomedusae, Laingiomedusae))) or Hydroidolina (Leptothecata (Siphonophorae, Anthoathecata)). Cladistic results are highly congruent with recently published phylogenetic analyses based on 18S molecular characters. We propose a phylogenetic classification of Medusozoa that is consistent with phylogenetic hypotheses based on our cladistic results, as well as those derived from 18S analyses. Optimization of the characters presented in this analysis are used to discuss evolutionary scenarios. The ancestral cnidarian probably had a sessile biradial polyp as an adult form. The medusa is inferred to be a synapomorphy of Medusozoa. However, the ancestral process (metamorphosis of the apical region of the polyp or lateral budding involving an entocodon) could not be inferred unequivocally. Similarly, character states for sense organs and nervous systems could not be inferred for the ancestral medusoid of Medusozoa. [source] Cause-specific mortality and death certificate reporting in adults with moderate to profound intellectual disabilityJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 11 2009F. Tyrer Abstract Background The study of premature deaths in people with intellectual disability (ID) has become the focus of recent policy initiatives in England. This is the first UK population-based study to explore cause-specific mortality in adults with ID compared with the general population. Methods Cause-specific standardised mortality ratios (SMRs) and exact 95% confidence intervals were calculated by age and sex for adults with moderate to profound ID living in the unitary authorities of Leicester, Leicestershire and Rutland, UK, between 1993 and 2006. Causes of death were also studied to determine how often ID and associated conditions, such as Down syndrome, were mentioned. Results A total of 503 (17% of population) adults with ID died during the 14-year study period (30 144 person-years). Relatively high cause-specific mortality was seen for deaths caused by congenital abnormalities (SMR = 8560), diseases of the nervous system and sense organs (SMR = 1630), mental disorders (other than dementia) (SMR = 1141) and bronchopneumonia (SMR = 647). Excess deaths were also seen for diseases of the genitourinary system or digestive system, cerebrovascular disease, other respiratory infections, dementia (in men only), other circulatory system diseases (in women only) and accidental deaths (in women only). Two-fifths (n = 204; 41%) of deaths recorded in adults with ID mentioned ID or an associated condition as a contributing cause of death. Conclusions Strategies to reduce inequalities in people with ID need to focus on decreasing mortality from potentially preventable causes, such as respiratory infections, circulatory system diseases and accidental deaths. The lack of mention of ID on death certificates highlights the importance of effective record linkage and ID reporting in health and social care settings to facilitate the government's confidential inquiry into causes of death in this population. [source] Pigmented eyes, photoreceptor-like sense organs and central nervous system in the polychaete Scoloplos armiger (Orbiniidae, Annelida) and their phylogenetic importanceJOURNAL OF MORPHOLOGY, Issue 11 2009Verena Wilkens Abstract The phylogenetic position of Orbiniidae within Annelida is unresolved. Conflicting hypotheses place them either in a basal taxon Scolecida, close to Spionida, or in a basal position in Aciculata. Because Aciculata have a specific type of eye, the photoreceptive organs in the orbiniid Scoloplos armiger were investigated to test these phylogenetic hypotheses. Two different types of prostomial photoreceptor-like sense organs were found in juveniles and one additional in subadults. In juveniles there are four ciliary photoreceptor-like phaosomes with unbranched cilia and two pigmented eyes. The paired pigmented eyes lie beside the brain above the circumoesophageal connectives. Each consists of one pigmented cell, one unpigmented supportive cell and three everse rhabdomeric sensory cells with vestigial cilia. During development the number of phaosomes increases considerably and numerous unpigmented sense organs appear consisting of one rhabdomeric photoreceptor cell and one supportive cell. The development and morphology of the pigmented eyes of S. armiger suggest that they represent miniaturized eyes of the phyllodocidan type of adult eye rather than persisting larval eyes resulting in small inverse eyes typical of Scolecida. Moreover, the structure of the brain indicates a loss of the palps. Hence, a closer relationship of Orbiniidae to Phyllodocida is indicated. Due to a still extensive lack of ultrastructural data among polychaetes this conclusion cannot be corroborated by considering the structure of the unpigmented ciliary and rhabdomeric photoreceptor-like sense organs. J. Morphol., 2009. © 2009 Wiley-Liss, Inc. [source] Growth and development of giant panda (Ailuropoda melanoleuca) cubs at Beijing ZooJOURNAL OF ZOOLOGY, Issue 2 2001Jianjun Peng Abstract We studied the postnatal body weight gain and development of 11 male and nine female giant panda Ailuropoda melanoleuca cubs born at Beijing Zoo from 1985 to 1998. Growth rates of the cubs appeared to be sexually dimorphic from the fourth month after birth; the male grew slightly faster than the female cubs. Growth rates between artificially fed and naturally fed cubs were significantly different from the fourth month after birth. The growth rate of the artificially fed cubs was slightly higher than that of the cubs fed by their mothers, indicating that the substitute milk satisfied the nutrient needs of the cubs. The body length of the cubs increased rapidly after birth; 8-month-old cubs were three times longer than newborn cubs. Chest circumferences of 8-month-old cubs also increased to twice that of newborn cubs. Tail length relative to body length was reduced from 14.9% at birth to about 8.6% in 8-month-old cubs. Cubs started to grow teeth when they were 3 months old. By the age of 1 year, the cubs had fully grown deciduous teeth. The teeth formula of one 1-year-old cub was 2·1·3·0/2·1·3·0=24. We recorded the changes in fur colour, development of the sense organs and limbs of the giant panda cubs. Finally, we compared the body weight and life-history parameters of giant pandas with those of bears and raccoons and discussed the management regime for the care of captive-born giant panda cubs. [source] Dynamics of intracohort cannibalism in cultured fishAQUACULTURE RESEARCH, Issue 7 2002E Baras Abstract Cannibalism is a frequent phenomenon in fish, especially in culture environments where fish are unable to escape predation via habitat segregation or migration. Not all cultured fish species start to exhibit cannibalism at the same age or size, nor is cannibalism equally intense in different species or life stages. Predator to prey size ratios vary substantially between species and life stages, chiefly because cannibalism is governed by gape size limitations and allometric growth of mouthparts. The development of sense organs, hard body parts, swimming and escape capacities in both the predator and the prey also influence prey size selectivity. The dynamics of cannibalism are influenced by these, as well as by environmental, factors that have effects on feed intake, growth depensation and facilitate or complicate the displaying of cannibalistic behaviour. Knowledge about cannibalistic behaviour and the logistics of cannibalism along with environmental enhancement are prerequisites for the mitigation of cannibalism in aquaculture. Also, within the context of strain selection, it is of importance to determine whether cannibals are natural-born killers or just lottery winners. These factors are discussed, chiefly as they apply to intracohort cannibalism. In addition, guidelines are suggested for cannibalistic risk assessment, and methods for mitigation of cannibalism are discussed. [source] | ||||||||||