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Maintenance and degradation of proteins in intact and severed axons: Implications for the mechanism of long-term survival of anucleate crayfish axons
Protein maintenance and degradation are examined in the
severed distal (anucleate) portions of crayfish medial giant
axons (MGAs), which remain viable for over 7 months following
axotomy. On polyacrylamide gels, the silver-stained
protein banding pattern of anucleate MGAs severed from
their cell bodies for up to 4 months remains remarkably similar
to that of intact MGAs. At 7 months postseverance, some
(but not all) proteins are decreased in anucleate MGAs compared
to intact MGAs. To determine the half-life of axonally
transported proteins, we radiolabeled MGA cell bodies and
monitored the degradation of newly synthesized transported
proteins. Assuming exponential decay, proteins in the fast
component of axonal transport have an average half-life of
14 d in anucleate MGAs and proteins in the slow component
have an average half-life of 17 d. Such half-lives are very
unlikely to account for the ability of anucleate MGAs to survive
for over 7 months after axotomy.This work was supported by an ATP grant to G.D.B.Neuroscienc
Parties and party systems change
This is the author accepted manuscript. The final version is available from Edinburgh University Press via the link in this record.This chapter examines parties and party system change across the Middle East and North Africa (MENA) since the eruption of the Arab Spring in December 2010. Hence, the discussion begins with an overview of the parties and party systems in the region on the eve of the Arab Spring, thereby providing a quick introduction to the cases as well as a benchmark against which to measure change, while also anchoring the analysis in the theoretical framework outlined previously in chapter 1. [...
OPTIMAL SPATIAL ALLOCATION OF WASTE MANAGEMENT PRACTICES TO REDUCE PHOSPHORUS POLLUTION IN A WATERSHED
Phosphorus pollution from excessive litter application and municipal discharges causes eutorphication of lakes in the Eucha-Spavinaw watershed in eastern Oklahoma and western Arkansas. Consequent algae blooms impair the taste of drinking water supply drawn from the watershed and reduce the recreational values of the lakes. The paper shows how GIS data based biophysical modeling can be used to derive spatially optimal, least-cost allocation of agricultural management practices to be combined with optimal wastewater treatment activity from the point source in order to achieve socially optimal phosphorus load in the watershed. The optimal level of phosphorus load is determined by equating marginal abatement with marginal damage cost. Transportation activities in the model allow for transportation of litter within and out of the watershed. Results show uniform regulation of litter application is excessively costly relative to measures that encourage adoption of management practices that equate marginal abatement costs across pollution sources. The results also show that change in the land use patterns in a long-run and using alum based litter additives in short-run are economically efficient management options.Environmental Economics and Policy,
Is Anthropogenic Habitat Change The Driving Force Of Rapid Evolution Of Southeastern U.S. Coastal Deer Populations?
Existential concerns as predictors of spiritual emergency and psychosis
The cause of psychosis remains uncertain, and the current biological model for treating psychosis is only about 41% effective. Calls have been made for new hypotheses to be examined to aid in the understanding and treatment of psychosis. Evidence suggests that spiritual emergency (SE) can be psychologically healing and can be differentiated from psychosis by its divergent relationship with alogia and depression. Existential psychologists have posited a relationship between psychosis and existential distress (ED). The present study aimed to confirm alogia and depression as differentiating variables between psychosis and SE, in addition to exploring the relationships SE and psychosis have with existential concerns (ECs). Results confirmed that alogia and depression predict psychosis only, and there was no overlap in the ECs that predicted SE and psychosis. Psychosis was predicted by increased death anxiety, existential loneliness, and identity distress, while increased meaning (search for and presence of), psychological reactance, and decreased death anxiety predicted SE. The results indicate that SE may lead to psychological healing given the reduction in ED, while psychosis seems more a means of coping with ED. The findings have implications for the diagnosis of and potential treatments for psychosis.Maximilian Inglis, Lance Stor
The Economics of Efficient Phosphorus Abatement in a Watershed
This study presents a method to determine efficient environmental targets at a watershed level. Efficient targets are devised by estimating abatement cost and cost of environmental damages and minimizing their sum. The method was applied to a case study of phosphorus pollution in a watershed in Oklahoma. Several cumulative scenarios with alternative abatement options were simulated and efficient targets were determined. As the number of abatement options at disposal to agricultural sources increased, their optimal abatement expanded relative to the abatement at the point source. Efficient targets were found to be dependent on the choice of policy that stimulates abatement.efficiency, environmental targets, phosphorus pollution, watershed, Resource /Energy Economics and Policy,
BVRIJK light curves and radial velocity curves for selected Magellanic Cloud Cepheids
We present high precision and well sampled BVRIJK light curves and radial
velocity curves for a sample of five Cepheids in the SMC. In addition we
present radial velocity curves for three Cepheids in the LMC. The low
metallicity (Fe/H ~ -0.7) SMC stars have been selected for use in a
Baade-Wesselink type analysis to constrain the metallicity effect on the
Cepheid Period-Luminosity relation. The stars have periods of around 15 days so
they are similar to the Cepheids observed by the Extragalactic Distance Scale
Key Project on the Hubble Space Telescope. We show that the stars are
representative of the SMC Cepheid population at that period and thus will
provide a good sample for the proposed analysis. The actual Baade-Wesselink
analysis are presented in a companion paper.Comment: Accepted for publication in A&A, 23 pages, 10 figures, data tables
will be made available electronically from the CD
Economic Analysis of Management Practices to Reduce Phosphorus Load to Lake Eucha and Spavinaw
Changes in management practices are often proposed to reduce phosphorus loading from a watershed due to over application of poultry litter. This study determines the choice, location, and level of each best management practice in the watershed to meet a Total Maximum Daily Load and margins of safety at least cost.best management practice, phosphorus runoff, poultry litter, Target MOTAD, Environmental Economics and Policy,
Evaluation of SIR-A space radar for geologic interpretation: United States, Panama, Colombia, and New Guinea
Comparisons between LANDSAT MSS imagery, and aircraft and space radar imagery from different geologic environments in the United States, Panama, Colombia, and New Guinea demonstrate the interdependence of radar system geometry and terrain configuration for optimum retrieval of geologic information. Illustrations suggest that in the case of space radars (SIR-A in particular), the ability to acquire multiple look-angle/look-direction radar images of a given area is more valuable for landform mapping than further improvements in spatial resolution. Radar look-angle is concluded to be one of the most important system parameters of a space radar designed to be used for geologic reconnaissance mapping. The optimum set of system parameters must be determined for imaging different classes of landform features and tailoring the look-angle to local topography
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