2,291 research outputs found
Active Travel Co-Benefits of Travel Demand Management Policies that Reduce Greenhouse Gas Emissions, MTI Report 12-12
There is increasing evidence that improved health outcomes may be significant co-benefits of land use plans and transport policies that increase active transport (or walking and biking for purposeful travel) and reduce greenhouse gas emissions (GHGs) from vehicle miles traveled (VMT). A greater understanding of these benefits may broaden the constituency for regional planning that supports local and national GHG reduction goals. In this study, Californiaâs activity-based travel demand model (ABM) is applied to (1) demonstrate how this new generation of travel models can be used to produce the active travel data (age and sex distributions) required by comparative risk assessment models to estimate health outcomes for alternative land use and transport plans and to (2) identify the magnitude of change in active travel that may be possible from land use, transit, and vehicle pricing policies for California and its five major regions for a future 2035 time horizon. The results of this study suggest that distance-based vehicle pricing may increase walking by about 10% and biking by about 17%, and concurrently GHG from VMT may be reduced by about 16%. Transit expansion and supportive development patterns may increase active travel by about 2% to 3% for both walk and bike modes while also reducing VMT by about 4% on average. The combination of all three policies may increase time spent walking by about 13% and biking by about 19%, and reduce VMT by about 19%
Development of a prototype blood fractionation cartridge for plasma analysis by paper spray mass spectrometry
Drug monitoring of biofluids is often time consuming and prohibitively expensive. Analysis of dried blood spots offers advantages, such as reduced sample volume, but depends on extensive sample preparation and the presence of a trained lab technician. Paper spray mass spectrometry allows rapid analysis of small molecules from blood spots with minimal sample preparation, however, plasma is often the preferred matrix for bioanalysis. Plasma spots can be analyzed by paper spray MS, but a centrifugation step to isolate the plasma is required. We demonstrate here the development of a paper spray cartridge containing a plasma fractionation membrane to perform automatic on-cartridge plasma fractionation from whole blood samples. Three commercially available blood fractionation membranes were evaluated based on: 1) accuracy of drug concentration determination in plasma, and 2) extent of cell lysis and/or penetration. The accuracy of drug concentration determination was quantitatively determined using high performance liquid chromatographyâmass spectrometry (HPLCâMS). While the fractionation membranes were capable of yielding plasma samples with low levels of cell lysis, the membranes did exhibit drug binding to varying degrees, as indicated by a decrease in the drug concentration relative to plasma obtained by centrifugation. Using the membrane exhibiting the lowest binding, we developed a composite paper spray cartridge incorporating the selected fractionation membrane. Quantitative analysis of the plasma samples by paper spray MS yielded results similar to those found with HPLCâMS, but without the need for offline extraction or chromatography
Analysis of Biofluids by Paper Spray Mass Spectrometry: Advances and Challenges
Abstract
Paper spray MS is part of a cohort of ambient ionization or direct analysis methods that seek to analyze complex samples without prior sample preparation. Extraction and electrospray ionization occur directly from the paper substrate upon which a dried matrix spot is stored. Paper spray MS is capable of detecting drugs directly from dried blood, plasma and urine spots at the low ng/ml to pg/ml levels without sample preparation. No front end separation is performed, so MS/MS or high-resolution MS is required. Here, we discuss paper spray methodology, give a comprehensive literature review of the use of paper spray MS for bioanalysis, discuss technological advancements and variations on this technique and discuss some of its limitations
Selection for High Alcohol Preference Drinking in Mice Results in Heightened Sensitivity and Rapid Development of Acute Functional Tolerance to Alcoholâs Ataxic Effects
Selection for High Alcohol Preference Drinking in Mice Results
in Heightened Sensitivity and Rapid Development of Acute
Functional Tolerance to Alcoholâs Ataxic Effects
Brandon M. Fritz
,
Nicholas J. Grahame
, and
Stephen L. Boehm II
Indiana Alcohol Research Center and Department of Psychology, Indiana University â Purdue
University Indianapolis, Indianapolis, IN 46202
Abstract
Propensity to develop acute functional (or within session) tolerance to alcohol (ethanol) may
influence the amount of alcohol consumed, with higher drinking associated with greater acute
functional tolerance (AFT). The goal of the current study was to assess this potential correlated
response between alcohol preference and AFT in second and third replicate lines of mice
selectively bred for high (HAP2&3) and low (LAP2&3) alcohol preference drinking. Male and
female mice were tested for development of AFT on a static dowel task which requires that
animals maintain balance on a wooden dowel in order to prevent falling. On test day, each mouse
received one (1.75g/kg; Experiment 1) or two (1.75g/kg and 2.0g/kg; Experiment 2) injections of
ethanol; an initial administration before being placed on the dowel and in Experiment 2, an
additional administration after the first regain of balance on the dowel. Blood samples were taken
immediately after loss of balance (when BECs were rising) and at recovery (during falling BECs)
in Experiment 1, and after first and second recovery in Experiment 2. It was found that HAP mice
fell from the dowel significantly earlier and at lower BECs than LAP mice following the initial
injection of ethanol and were therefore more sensitive to its early effects. Furthermore,
Experiment 1 detected significantly greater AFT development (BECfalling - BECrising) in HAP
mice as compared to LAP mice which occurred within ~30 min, supporting our hypothesis.
However, AFT was not different between lines in Experiment 2, indicating that ~30â60 min
following alcohol administration, AFT development was similar in both lines. These data show
that high alcohol drinking genetically associates with both high initial sensitivity and very early
tolerance to the ataxic effects of ethanol
Macroeconomic Modeling of Tax Policy: A Comparison of Current Methodologies
The macroeconomic effects of tax reform are a subject of significant discussion and controversy. In 2015, the House of Representatives adopted a new âdynamic scoringâ rule requiring a point estimate within the budget window of the deficit effect due to the macroeconomic response to certain proposed tax legislation. The revenue estimates provided by the staff of the Joint Committee on Taxation (JCT) for major tax bills often play a critical role in Congressional deliberations and public discussion of those bills. The JCT has long had macroeconomic analytic capability, and in recent years, responding to Congressâ interest in macrodynamic estimates for purposes of scoring legislation, outside think tank groups â notably the Tax Policy Center and the Tax Foundation â have also developed macrodynamic estimation models. The May 2017 National Tax Association (NTA) Spring Symposium brought together the JCT with the Tax Foundation and the Tax Policy Center for a panel discussion regarding their respective macrodynamic estimating approaches. This paper reports on that discussion. Below each organization provides a general description of their macrodynamic modeling methodology and answers five questions posed by the convening authors
Ionization Suppression and Recovery in Direct Biofluid Analysis using Paper Spray Mass Spectrometry
Paper spray mass spectrometry is a method for the direct analysis of biofluid samples in which extraction of analytes from dried biofluid spots and electrospray ionization occur from the paper on which the dried sample is stored. We examined matrix effects in the analysis of small molecule drugs from urine, plasma, and whole blood. The general method was to spike stable isotope labeled analogs of each analyte into the spray solvent, while the analyte itself was in the dried biofluid. Intensity of the labeled analog is proportional to ionization efficiency, whereas the ratio of the analyte intensity to the labeled analog in the spray solvent is proportional to recovery. Ion suppression and recovery were found to be compound- and matrix-dependent. Highest levels of ion suppression were obtained for poor ionizers (e.g., analytes lacking basic aliphatic amine groups) in urine and approached â90%. Ion suppression was much lower or even absent for good ionizers (analytes with aliphatic amines) in dried blood spots. Recovery was generally highest in urine and lowest in blood. We also examined the effect of two experimental parameters on ion suppression and recovery: the spray solvent and the sample position (how far away from the paper tip the dried sample was spotted). Finally, the change in ion suppression and analyte elution as a function of time was examined by carrying out a paper spray analysis of dried plasma spots for 5 min by continually replenishing the spray solvent
PDE10A mutations help to unwrap the neurobiology of hyperkinetic disorders
The dual-specific cAMP/cGMP phosphodiesterase PDE10A is exclusively localised to regions of the brain and specific cell types that control crucial brain circuits and behaviours. The downside to this expression pattern is that PDE10A is also positioned to be a key player in pathology when its function is perturbed. The last decade of research has seen a clear role emerge for PDE10A inhibition in modifying behaviours in animal models of psychosis and Huntington's disease. Unfortunately, this has not translated to the human diseases as expected. More recently, a series of families with hyperkinetic movement disorders have been identified with mutations altering the PDE10A protein sequence. As these mutations have been analysed and characterised in other model systems, we are beginning to learn more about PDE10A function and perhaps catch a glimpse into how PDE10A activity could be modified for therapeutic benefit
Pairing Neutral Cues with Alcohol Intoxication: New Findings in Executive and Attention Networks
Rationale:
Alcohol-associated stimuli capture attention, yet drinkers differ in the precise stimuli that become paired with intoxication.
Objectives:
Extending our prior work to examine the influence of alcoholism risk factors, we paired abstract visual stimuli with intravenous alcohol delivered covertly and examined brain responses to these Pavlovian conditioned stimuli in fMRI when subjects were not intoxicated.
Methods:
Sixty healthy drinkers performed task-irrelevant alcohol conditioning that presented geometric shapes as conditioned stimuli. Shapes were paired with a rapidly rising alcohol limb (CS+) using intravenous alcohol infusion targeting a final peak breath alcohol concentration of 0.045 g/dL or saline (CSâ) infusion at matched rates. On day two, subjects performed monetary delay discounting outside the scanner to assess delay tolerance and then underwent event-related fMRI while performing the same task with CS+, CSâ, and an irrelevant symbol.
Results:
CS+ elicited stronger activation than CSâ in frontoparietal executive/attention and orbitofrontal reward-associated networks. Risk factors including family history, recent drinking, sex, and age of drinking onset did not relate to the [CS+ > CSâ] activation. Delay-tolerant choice and [CS+ > CSâ] activation in right inferior parietal cortex were positively related.
Conclusions:
Networks governing executive attention and reward showed enhanced responses to stimuli experimentally paired with intoxication, with the right parietal cortex implicated in both alcohol cue pairing and intertemporal choice. While different from our previous study results in 14 men, we believe this paradigm in a large sample of male and female drinkers offers novel insights into Pavlovian processes less affected by idiosyncratic drug associations
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