1,099 research outputs found

    Plutarch's treatment of the Isis-Osiris cult in the De Iside et Osiride

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    Thesis (Ph.D.)--Boston UniversityPlutarch's De Iside et Osiride is an interpretative rather than an historical document, yet has never been studied as such. The problem of the present investigation is the examination of the treatise and its backgrounds with the intent of discovering why Plutarch wrote the essay, what he hoped to achieve by so doing, and what methods and techniques he employed in the endeavor

    Pax2/8 proteins coordinate sequential induction of otic and epibranchial placodes through differential regulation of foxi1, sox3 and fgf24

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    AbstractVertebrate cranial placodes contribute vitally to development of sensory structures of the head. Amongst posterior placodes, the otic placode forms the inner ear whereas nearby epibranchial placodes produce sensory ganglia within branchial clefts. Though diverse in fate, these placodes show striking similarities in their early regulation. In zebrafish, both are initiated by localized Fgf signaling plus the ubiquitous competence factor Foxi1, and both express pax8 and sox3 in response. It has been suggested that Fgf initially induces a common otic/epibranchial field, which later subdivides in response to other signals. However, we find that otic and epibranchial placodes form at different times and by distinct mechanisms. Initially, Fgf from surrounding tissues induces otic expression of pax8 and sox3, which cooperate synergistically to establish otic fate. Subsequently, pax8 works with related genes pax2a/pax2b to downregulate otic expression of foxi1, a necessary step for further otic development. Additionally, pax2/8 activate otic expression of fgf24, which induces epibranchial expression of sox3. Knockdown of fgf24 or sox3 causes severe epibranchial deficiencies but has little effect on otic development. These findings clarify the roles of pax8 and sox3 and support a model whereby the otic placode forms first and induces epibranchial placodes through an Fgf-relay

    Spemann organizer gene Goosecoid promotes delamination of neuroblasts from the otic vesicle

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    Neurons of the Statoacoustic Ganglion (SAG), which innervate the inner ear, originate as neuroblasts in the floor of the otic vesicle and subsequently delaminate and migrate toward the hindbrain before completing differentiation. In all vertebrates, locally expressed Fgf initiates SAG development by inducing expression of Neurogenin1 (Ngn1) in the floor of the otic vesicle. However, not all Ngn1-positive cells undergo delamination, nor has the mechanism controlling SAG delamination been elucidated. Here we report that Goosecoid (Gsc), best known for regulating cellular dynamics in the Spemann organizer, regulates delamination of neuroblasts in the otic vesicle. In zebrafish, Fgf coregulates expression of Gsc and Ngn1 in partially overlapping domains, with delamination occurring primarily in the zone of overlap. Loss of Gsc severely inhibits delamination, whereas overexpression of Gsc greatly increases delamination. Comisexpression of Ngn1 and Gsc induces ectopic delamination of some cells from the medial wall of the otic vesicle but with a low incidence, suggesting the action of a local inhibitor. The medial marker Pax2a is required to restrict the domain of gsc expression, and misexpression of Pax2a is sufficient to block delamination and fully suppress the effects of Gsc. The opposing activities of Gsc and Pax2a correlate with repression or up-regulation, respectively, of E-cadherin (cdh1). These data resolve a genetic mechanism controlling delamination of otic neuroblasts. The data also elucidate a developmental role for Gsc consistent with a general function in promoting epithelial-to-mesenchymal transition (EMT)

    Necklace Radio Transmitter Attachment For Pheasants

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    We tested a pre-assembled, necklace-radio-transmitter-attachment design on female ring-necked pheasants (Phasianus colchicus) in northern Iowa. Birds were captured by nightlighting and bait trapping between September 1989 and March 1990. Radio transmitters were attached to 128 using a wire necklace. Two birds had problems adapting to the necklace, and 3 birds removed them. Twenty-three birds were still alive and wearing necklaces at the end of the study, for an average of 318 (SD= Β± 52) days. Ease of attachment, long durability, light weight, and minimal bulk make the necklace an effective alternative to harness and poncho mounts

    The Liquidation-Reincorporation Device - Analysis and Proposed Solutions

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    Voices from the uncanny valley: How robots and artificial intelligences talk back to us.

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    Voice is a powerful tool of agency – for humans and non-humans alike. In this article, we go through the long history of talking heads and statues to publicly displayed robots and fortune-tellers, as well as consumer-oriented products such as the late 19thcentury talking dolls of Thomas Edison. We also analyse the attempts at making speaking machines commercially successful on various occasions. In the end, we investigate how speech producing devices such as the actual digital assistants that operate our current technological systems fit into this historical context. Our focus is on the gender aspects of the artificial, posthuman voice. On the basis of our study, we conclude that the female voice and other feminine characteristics as well as the figures of exoticized and racialized β€˜Others’ have been applied to draw attention away from the uncanniness and other negative effects of these artificial humans and the machinic speech they produce. Technical problems associated with the commercialization of technologically produced speech have been considerable, but cultural issues have played an equally important role

    Evaluation of the School Administration Manager Project

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    Examines the results to date of a Wallace-supported project to help principals delegate some administrative and managerial tasks to school administration managers and spend more time interacting with teachers, students and others on instructional matters

    Development and Regeneration of the Zebrafish Maxillary Barbel: A Novel Study System for Vertebrate Tissue Growth and Repair

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    , catfish) are known to regenerate; however, this capacity has not been tested in zebrafish., we demonstrate that the barbel contains a long (∼2–3 mm) closed-end vessel that we interpret as a large lymphatic. The identity of this vessel was further supported by live imaging of the barbel circulation, extending recent descriptions of the lymphatic system in zebrafish. The maxillary barbel can be induced to regenerate by proximal amputation. After more than 750 experimental surgeries in which approximately 85% of the barbel's length was removed, we find that wound healing is complete within hours, followed by blastema formation (∼3 days), epithelial redifferentiation (3–5 days) and appendage elongation. Maximum regrowth occurs within 2 weeks of injury. Although superficially normal, the regenerates are shorter and thicker than the contralateral controls, have abnormally organized mesenchymal cells and extracellular matrix, and contain prominent connective tissue β€œstumps” at the plane of sectionβ€”a mode of regeneration more typical of mammalian scarring than other zebrafish appendages. Finally, we show that the maxillary barbel can regenerate after repeated injury and also in senescent fish (>2 years old).Although the teleost barbel has no human analog, the cell types it contains are highly conserved. Thus β€œbarbology” may be a useful system for studying epithelial-mesenchymal interactions, angiogenesis and lymphangiogenesis, neural pathfinding, wound healing, scar formation and other key processes in vertebrate physiology

    Integrin-Ξ±5 Coordinates Assembly of Posterior Cranial Placodes in Zebrafish and Enhances Fgf-Dependent Regulation of Otic/Epibranchial Cells

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    Vertebrate sensory organs develop in part from cranial placodes, a series of ectodermal thickenings that coalesce from a common domain of preplacodal ectoderm. Mechanisms coordinating morphogenesis and differentiation of discrete placodes are still poorly understood. We have investigated whether placodal assembly in zebrafish requires Integrin- Ξ±5 (itga5), an extracellular matrix receptor initially expressed throughout the preplacodal ectoderm. Morpholino knockdown of itga5 had no detectable effect on anterior placodes (pituitary, nasal and lens), but posterior placodes developed abnormally, resulting in disorganization of trigeminal and epibranchial ganglia and reduction of the otic vesicle. Cell motion analysis in GFP-transgenic embryos showed that cell migration in itga5 morphants was highly erratic and unfocused, impairing convergence and blocking successive recruitment of new cells into these placodes. Further studies revealed genetic interactions between itga5 and Fgf signaling. First, itga5 morphants showed changes in gene expression mimicking modest reduction in Fgf signaling. Second, itga5 morphants showed elevated apoptosis in the otic/epibranchial domain, which was rescued by misexpression of Fgf8. Third, knockdown of the Fgf effector erm had no effect by itself but strongly enhanced defects in itga5 morphants. Finally, proper regulation of itga5 requires dlx3b/4b and pax8, which are themselves regulated by Fgf. These findings support a model in which itga5 coordinates cell migration into posterior placodes and augments Fgf signaling required for patterning of these tissues and cell survival in otic/epibranchial placodes

    Sonification Mapping Configurations: Pairings Of Real-Time Exhibits And Sound

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    Presented at the 19th International Conference on Auditory Display (ICAD2013) on July 6-9, 2013 in Lodz, Poland.Visitors to aquariums typically rely on their vision to interact with live exhibits that convey rich descriptive and aesthetic visual information. However, some visitors may prefer or need to have an alternative interpretation of the exhibitΓ•s visual scene to improve their experience. Musical sonification has been explored as an interpretive strategy for this purpose and related work provides some guidance for sonification design, yet more empirical work on developing and validating the music-to-visual scene mappings needs to be completed. This paper discusses work to validate mappings that were developed through an investigation of musician performances for two specific live animal exhibits at the Georgia Aquarium. In this proposed study, participants will provide feedback on musical mapping examples which will help inform design of a real-time sonification system for aquarium exhibits. Here, we describe our motivation, methods, and expected contributions
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