Modulation of constant light effects on the eye by ciliary ganglionectomy and optic nerve section

AbstractOur previous studies have shown that an environment of constant light (CL) can lead to development of high degree of hyperopia in newborn chicks by inducing severe corneal flattening, and compensatory growth of the vitreous chamber. We wish to know whether the abnormal eye growth and progressive hyperopia under CL conditions is accomplished by a mechanism that uses the visual processing pathways of the central nervous system (CNS) or by a mechanism located in the eye. Thirty white leghorn chicks (Cornell K-strain) were raised under 12 h light/12 h dark (12L/12D) for either optic nerve section (ONS) or ciliary ganglion section (CGS). Another 30 chicks were raised under CL for ONS or CGS. Refractive states and corneal curvatures were measured by infrared (IR) photoretinoscopy and IR keratometry, respectively. The axial lengths of the ocular components were measured by A-scan ultrasonography. Both ONS and CGS surgery produced dilated pupils and accommodative paralysis. Four weeks after surgery, CGS eyes exhibited a hyperopic defocus, flatter cornea, and shorter vitreous chamber depth under both CL and normal conditions, whereas ONS eyes showed a smaller radius of corneal curvature and shallow vitreous chamber only in the normal light cycle group. CGS eyes of CL chicks showed significantly deeper vitreous chambers than did fellow control eyes. Our results indicate that optic nerve section does not seem to influence CL effects. Thus, local mechanisms may play a major role in the ocular development of chicks. The ciliary nerve is necessary for the normal corneal and anterior chamber growth, and prevents CL effects. The progressively increasing vitreous chamber depth under CL may be influenced by both local and central mechanisms

Multidecadal Climate Variability and the Florescence of Fremont Societies in Eastern Utah

Fremont societies of the Uinta Basin incorporated domesticates into a foraging lifeway over a 1,000-year period from AD 300 to 1300. Fremont research provides a unique opportunity to critically examine the social and ecological processes behind the adoption and abandonment of domesticates by hunter-gatherers. We develop and integrate a 2,115-year precipitation reconstruction with a Bayesian chronological model for the growth of Fremont societies in the Cub Creek reach of Dinosaur National Monument. Comparison of the archaeological chronology with the precipitation record suggests that the florescence of Fremont societies was an adaptation to multidecadal precipitation variability with an approximately 30-plus-year periodicity over most, but not all, of the last 2,115 years. Fremont societies adopted domesticates to enhance their resilience to periodic droughts. We propose that reduced precipitation variability from AD 750 to AD 1050, superimposed over consistent mean precipitation availability, was the tipping point that increased maize production, initiated agricultural intensification, and resulted in increased population and development of pithouse communities. Our study develops a multidecadal/multigenerational model within which to evaluate the strategies underwriting the adoption of domesticates by foragers, the formation of Fremont communities, and the inherent vulnerabilities to resource intensification that implicate the eventual dissolution of those communities. Las sociedades de Fremont de la cuenca de Uinta incorporaron a los domesticados en una forma de vida de alimentación durante un período de 1.000 años desde 300–1300 dC. La investigación de Fremont brinda una oportunidad única para examinar críticamente los procesos sociales y ecológicos detrás de la adopción y el abandono de los domésticos por parte de los cazadores-recolectores. Desarrollamos e integramos una reconstrucción de precipitación de 2.115 años con un modelo cronológico Bayesiano para el crecimiento de las sociedades de Fremont en el alcance de Cub Creek del Dinosaur National Monument. La comparación de la cronología arqueológica con el registro de precipitación sugiere que la floración de las sociedades de Fremont fue una adaptación a la variabilidad de precipitación multidecadal con una periodicidad de aproximadamente 30 años en la mayoría, pero no en todos, de los últimos 2.115 años. Las sociedades de Fremont adoptaron domesticados para mejorar su resistencia a las sequías periódicas. Proponemos que la variabilidad reducida de la precipitación desde 750–1050 dC, superpuesta sobre la disponibilidad de precipitación media constante, fue el punto de inflexión que aumentó la producción de maíz, inició la intensificación agrícola y dio como resultado un aumento de la población y el desarrollo de las comunidades de médulas. Nuestro estudio desarrolla un modelo multidecadal/multigeneracional dentro del cual evaluar las estrategias que sustentan la adopción de domesticados por parte de los recolectores, la formación de comunidades de Fremont y las vulnerabilidades inherentes a la intensificación de recursos que implican la eventual disolución de esas comunidades

Antigen recognized by monoclonal antibodies to mesencephalic neural crest and to ciliary ganglion neurons is involved in the high affinity choline uptake mechanism in these cells

High-affinity choline uptake mechanisms are among the characteristics of cholinergic neurons such as the ciliary and choroid subpopulations in the ciliary ganglion (Barald and Berg, 1979). We have produced three monoclonal antibodies (Mabs), two of which were made to 8-day embryonic chick ciliary ganglion (CG) neurons (CG-1, CG-4) (Barald, 1982) and one of which was made to cultured mesencephalic neural crest (NC) cells (CG-14) removed from the embryo 31 hr after incubation. We have shown that all three Mabs label a common 75 kD antigen present on the cell surface of both CG neurons and NC cells (Barald, 1988). Here we report that the CG-1 and CG-4 antibodies, used in the same ratios in which they are synergistically cytotoxic for both the CG and NC cells (Barald, 1988), and Mab CG-14 alone, have specific effects on the high-affinity choline uptake mechanism (HACU) of CG neurons and isolated antigen-positive NC cells in the absence of complement. CG-1 and CG-4 in ratios of 8/1 (the same ratios that are used to kill the CG and the NC subpopulation), but neither singly, inhibit the HACU of CG neurons by 40% and that of isolated antigen-positive NC cells by 75%. However, CG-14 alone, at 1 Μg/ml, inhibits the HACU of both CG neurons and isolated NC cells by 95%. None of the antibodies had an effect on numbers of ouabain binding sites (a measure of the Na + /K + ATPase) or cell surface acetylcholinesterase (AChE) of CG neurons or NC cells isolated by “no-flow” fluorescence cytometry with a Meridian Instruments ACAS470 cytometer. CG or NC cells grown in the presence of the antibodies without complement grow and remain healthy for many weeks. They exhibit no difference in morphology, protein content, lactate dehydrogenase activity (LDH), or division time from untreated sister cultures. Therefore, the antigen recognized by all three Mabs may be involved in a high-affinity choline uptake mechanism, a common characteristic of cholinergic neurons. The Mabs themselves may possibly label some element of the high-affinity transporter or a proximal membrane component. This implies that such a high-affinity uptake mechanism is present in the subpopulation of NC cells at early times in development. If these cells in fact are destined to contribute to the avian CG, these characteristics are present in the subpopulation before the NC cells take on a neuronal morphology.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50220/1/490210205_ftp.pd

Fry and Dalley: The Levee Site and the Knoll Site

The Levee Site and the Knoll Site. Gary F. Fry and Gardiner F. Dalley. University of Utah Anthropological Papers No. 100, 1979, x + 113 pp., 68 figs., 4 tables, 3 appendices. $8.00

Antiquities Selection Selected Paper 1-16

Antiquities Section Selected Papers 1-16. David B. Madsen. ed. Salt Lake City: Utah Historical Society Division of State History, 7 vols., 1975-1980, $5.50 per volume individually or the seven for$35.00 if ordered together

Doctor of Philosophy

dissertationExcavations at Median Village, in Southwestern Utah revealed a complex of dwellings, one storage structure and other phenomena radiocarbon dated to between A. D. 900 + 100. The unusual uniformity of the artifact assemblage fro the site together with the virtual absence of Snake Valley corrugated pottery and quadrilateral pit dwellings are evidence that Median Village cannot be assigned to a generalized Sevier Fremont or Western Fremont Culture which fails to take regional and temporal variation into account. A system of regional variants and local phases is therefore proposed for the whole of Fremont culture, with the phases having a temporal as well as a geographic component. Five regional variants, Uinta Fremont and San Rafael Fremont in the eastern part of the Fremont area, and Great Salt Lake Fremont, Sevier Fremont and Parowan Fremont in western Utah and eastern Nevada are defined. Criteria used for definition include1) presence or absence of material culture traits, 2) relative percentage of traits, and 3) settlement pattern and economic orientation. Phases are distinguished for local areas, according to the same set of criteria, where sufficient comparative data and controlled dating permit the recognition of local cultural change. Cultural boundaries between regional variants are not, for the most part, well-defined and cultural transitions are gradual. It is also probable that boundaries were not stable through time. Developments within each of the regional variants were not synchronous and no single beginning and no single beginning or ending date will fit all of Fremont Culture. A distinctive Fremont pattern can be recognized by A. D. 400 to 500 in the Great Salt Lake variant, and by A. D. 650 in the Uinta variant, but not until about A.D. 700 in the case of the San Rafael and even later in the Sevier and Parowan variants. Uinta Fremont does not seem to have persisted until after about A. D. 950 while abandonment of the rest of the Fremont area did not take place until after A. D. 1300. Fremont culture is seen as a unique pattern with its own set of traditions, deriving largely from a regionally differentiated Desert Archaic base to which was added before A. D. 500, a horticultural village or farmstead component whose origin was in the west central New Mexico - east central Arizona area. Subsequent to the introduction of horticulture, Fremont culture developed without important influence from the South west until the rise of the great Anasazi centers about A. D. 900. After this time, Anasazi influence became more marked, giving to Fremont culture, especially the Parowan and San Rafael variants, an Anasazi cast that obscured hundreds of years of indigenous development