Age-Based Property Tax Exemptions in Georgia

Many local jurisdictions offer property tax exemptions or similar concessions to older citizens, especially from the school portion of the tax bill. Such exemptions can be controversial. This report is a step toward informing (but surely not settling!) such debates in Georgia. First, we apprise readers of a new resource, the Georgia Property Tax Database, housed at Georgia State University’s Fiscal Research Center. Second, we describe the patterns of the data, documenting the kinds of jurisdictions offering age-targeted exemptions and the steady increase in their prevalence and coverage over time. Third, we show how these data can be used to estimate the fiscal impacts of such exemptions on local budgets using static scoring. Fourth, we show how the data can be used to estimate the effect of these exemptions on the migratory and location decisions of older households. Finally, we include an age-based homestead exemption estimate calculator in the appendix

Late 20th Century Indian Ocean Heat Content Gain Masked by Wind Forcing

Rapid increases in upper 700‐m Indian Ocean heat content (IOHC) since the 2000s have focused attention on its role during the recent global surface warming hiatus. Here, we use ocean model simulations to assess distinct multidecadal IOHC variations since the 1960s and explore the relative contributions from wind stress and buoyancy forcing regionally and with depth. Multidecadal wind forcing counteracted IOHC increases due to buoyancy forcing from the 1960s to the 1990s. Wind and buoyancy forcing contribute positively since the mid‐2000s, accounting for the drastic IOHC change. Distinct timing and structure of upper ocean temperature changes in the eastern and western Indian Ocean are linked to the pathway how multidecadal wind forcing associated with the Interdecadal Pacific Oscillation is transmitted and affects IOHC through local and remote winds. Progressive shoaling of the equatorial thermocline—of importance for low‐frequency variations in Indian Ocean Dipole occurrence—appears to be dominated by multidecadal variations in wind forcing

Air pollution, epigenetics, and asthma

Exposure to traffic-related air pollution (TRAP) has been implicated in asthma development, persistence, and exacerbation. This exposure is highly significant as large segments of the global population resides in zones that are most impacted by TRAP and schools are often located in high TRAP exposure areas. Recent findings shed new light on the epigenetic mechanisms by which exposure to traffic pollution may contribute to the development and persistence of asthma. In order to delineate TRAP induced effects on the epigenome, utilization of newly available innovative methods to assess and quantify traffic pollution will be needed to accurately quantify exposure. This review will summarize the most recent findings in each of these areas. Although there is considerable evidence that TRAP plays a role in asthma, heterogeneity in both the definitions of TRAP exposure and asthma outcomes has led to confusion in the field. Novel information regarding molecular characterization of asthma phenotypes, TRAP exposure assessment methods, and epigenetics are revolutionizing the field. Application of these new findings will accelerate the field and the development of new strategies for interventions to combat TRAP-induced asthma

Inverting Small Molecule-Protein Recognition by the Fluorine Gauche Effect: Selectivity Regulated by Multiple H→F Bioisosterism

Fluorinated motifs have a venerable history in drug discovery, but as C(sp3 )@F-rich 3D scaffolds appear with increasing frequency, the effect of multiple bioisosteric changes on molecular recognition requires elucidation. Herein we demonstrate that installation of a 1,3,5-stereotriad, in the substrate for a commonly used lipase from Pseudomonas fluorescens does not inhibit recognition, but inverts stereoselectivity. This provides facile access to optically active, stereochemically well-defined organofluorine compounds (up to 98% ee). Whilst orthogonal recognition is observed with fluorine, the trend does not hold for the corresponding chlorinated substrates or mixed halogens. This phenomenon can be placed on a structural basis by considering the stereoelectronic gauche effect inherent to F@C@C@X systems (s!s*). Docking reveals that this change in selectivity (H versus F) with a common lipase results from inversion in the orientation of the bound substrate being processed as a consequence of conformation. This contrasts with the stereochemical interpretation of the biogenetic isoprene rule, whereby product divergence from a common starting material is also a consequence of conformation, albeit enforced by two discrete enzymes

Autophagy, but Not Proteolysis, May Aid in Muscle Protein Synthesis

For muscle growth to occur, protein synthesis must be greater than protein degradation. However, up to this point, anabolic pathways have garnered the brunt of investigations examining anabolic capacity with little investigation into the connectedness of catabolic signaling on these anabolic targets. PURPOSE: The purpose of this study was to elucidate the contributions of proteasomal-dependent and autophagic-dependent catabolic pathways on anabolism via analysis of fractional synthetic rates (FSR) in L6 myotubes. METHODS: Differentiated, cultured L6 myoblasts were treated with media containing 4% deuterium oxide (stable isotope label) and a corresponding pharmacological treatment (NSC 185058 [autophagic inhibitor; 100 μM], MG-262 [proteasomal inhibitor; 0.01 μM] or DMSO control; n=3/group) during the final 24-hours of the differentiation period prior to harvest. The myofibrillar pellet of the processed samples was used to determine FSR via mass-spectrometry analysis. DMSO-treated myotubes served as controls, with a one-way analysis of variance and Tukey’s post-hoc test used to test for any differences among groups. RESULTS: Our results indicate that MG-262 had no impact on myofibrillar FSR when compared to DMSO control (MG-262 1.0993 %/day vs. control 1.239 %/day). However, NSC 185058 lowered myofibrillar FSR (NSC 185058 0.9009 %/day vs. control 1.239 %/day; P=0.0282). CONCLUSION: These data suggest that inhibition of autophagic machinery can impair anabolism. This may be due to autophagy’s role in increasing the amino acid pool within the cell. Further, the lack of inhibition seen from MG-262 suggests that there is a delineation of roles within the catabolic pathways in regard to their influence on anabolism in healthy, metabolically unchallenged myotubes

Spatial and Temporal Variation of Offshore Wind Power and its Values Along the Central California Coast

The analysis of the spatiotemporal variability of wind power remains limited during the planning stage of an offshore wind farm. This study provides a framework to investigate how offshore wind power varies along the Central California Coast over diurnal and seasonal time scales, which is critical for reliability and functionality of the grid system. We find that offshore wind power in this region peaks during evening hours across all seasons and maximizes in spring and summer. The timing of peak offshore wind power production better aligns with that of peak demand across California than solar and land-based wind power production, highlighting its potential to fill the supply gap when demand is high and power production from other renewable energy sources is low. We further assess the value of offshore wind power using demand-based and wholesale market metrics. Both metrics indicate high potential value of offshore wind power over most areas in this region. Finally, we show that the estimate of power production is significantly biased when using mean wind speeds that do not account for temporal variability, leading to potentially inaccurate predictions about locations that are expected to produce the most power. These results reiterate the importance in considering spatiotemporal variability in wind power for accurately calculating the value of offshore wind development

Assessment of NASA GISS CMIP5 and Post-CMIP5 Simulated Clouds and TOA Radiation Budgets Using Satellite Observations. Part I: Cloud Fraction and Properties

Although many improvements have been made in phase 5 of the Coupled Model Intercomparison Project (CMIP5), clouds remain a significant source of uncertainty in general circulation models (GCMs) because their structural and optical properties are strongly dependent upon interactions between aerosol/cloud microphysics and dynamics that are unresolved in such models. Recent changes to the planetary boundary layer (PBL) turbulence and moist convection parameterizations in the NASA GISS Model E2 atmospheric GCM(post-CMIP5, hereafter P5) have improved cloud simulations significantly compared to its CMIP5 (hereafter C5) predecessor. A study has been performed to evaluate these changes between the P5 and C5 versions of the GCM, both of which used prescribed sea surface temperatures. P5 and C5 simulated cloud fraction (CF), liquid water path (LWP), ice water path (IWP), cloud water path (CWP), precipitable water vapor (PWV), and relative humidity (RH) have been compared to multiple satellite observations including the Clouds and the Earth's Radiant Energy System-Moderate Resolution Imaging Spectroradiometer (CERES-MODIS, hereafter CM), CloudSat- Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO; hereafter CC), Atmospheric Infrared Sounder (AIRS), and Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E). Although some improvements are observed in the P5 simulation on a global scale, large improvements have been found over the southern midlatitudes (SMLs), where correlations increased and both bias and root-mean-square error (RMSE) significantly decreased, in relation to the previous C5 simulation, when compared to observations. Changes to the PBL scheme have resulted in improved total column CFs, particularly over the SMLs where marine boundary layer (MBL) CFs have increased by nearly 20% relative to the previous C5 simulation. Globally, the P5 simulated CWPs are 25 gm22 lower than the previous C5 results. The P5 version of the GCM simulates PWV and RH higher than its C5 counterpart and agrees well with the AMSR-E and AIRS observations. The moister atmospheric conditions simulated by P5 are consistent with the CF comparison and provide a strong support for the increase in MBL clouds over the SMLs. Over the tropics, the P5 version of the GCM simulated total column CFs and CWPs are slightly lower than the previous C5 results, primarily as a result of the shallower tropical boundary layer in P5 relative to C5 in regions outside the marine stratocumulus decks

Insulin-induced Increase in Anabolic Capacity is Blunted by Autophagic Inhibition in L6 Myotubes

Insulin is an anabolic hormone that acts on skeletal muscle cells to stimulate protein synthesis, an effect that is enhanced by the availability of amino acids. While autophagy within the cell provides an intracellular source of amino acids to support anabolism, little is known about how this pathway impacts the insulin-induced increase in anabolic capacity within skeletal muscle cells. PURPOSE: The purpose of this study was to determine the impact of autophagic inhibition in cultured L6 myotubes in conjunction with insulin stimulation in vitro. METHODS: Differentiated, cultured L6 myotubes were treated for 24 hours with or without insulin (100 nM) and NSC 185058 (100 μM), a specialized inhibitor of the autophagic catabolic pathway, in media enriched with 4% deuterium. Cells were harvested from each treatment group (n=3/group) 24 hours post-deuterium enrichment and were processed for protein synthesis and western blot protein analysis. A one-way ANOVA was used to compare groups, and when significant F ratios were present, a Student’s Newman-Keuls post hoc procedure was used to test differences among group means. Alpha was set at p≤0.05 for all analyses. RESULTS: Cells treated with insulin (INS) had a higher ratio of phosphorylated to total P70S6K compared to untreated (CON) cells and those incubated with both insulin and NSC 185058 (INS+NSC; 1694% and 327%, respectively; p\u3c0.05). INS+NSC also decreased the ratio of phosphorylated to total 4EBP1 relative to CON (-51%) and INS (-49%), although these differences were not significant (p\u3e0.05). Myofibrillar protein synthesis was stimulated with INS compared to CON and INS+NSC (30.3% and 70.1% respectively; p\u3c0.05) but was lower in INS+NSC relative to CON (-23.4%; p\u3c0.05). CONCLUSION: Results from our study indicate that insulin (100 nM) stimulates anabolism in skeletal muscle cells, but that addition of the autophagic inhibitor NSC 185058 (100 μM) blunts this effect to a level similar to or less than control. Further, our data suggest that the reduction of protein synthesis is mediated through the downregulation of the mTORC1 signaling pathway. While it is widely recognized that insulin promotes anabolic activity through both the direct stimulation of mTOR signaling and extracellular amino acid uptake, our data strongly indicate that autophagic processes are necessary for full anabolic responses in muscle. This decrease in anabolic capacity supports previous literature indicating that the amino acid availability impacts the stimulatory impact of insulin on protein synthesis