3,997 research outputs found
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California cannabis regulation: An overview
In 2016, Proposition 64 decriminalized the possession and use of cannabis by anyone in California aged 21 or over. But the 2015 Medical Marijuana Regulation and Safety Act had begun the process of regulating cannabis in the state
Observing the earliest moments of supernovae using strong gravitational lenses
We determine the viability of exploiting lensing time delays to observe
strongly gravitationally lensed supernovae (gLSNe) from first light. Assuming a
plausible discovery strategy, the Legacy Survey of Space and Time (LSST) and
the Zwicky Transient Facility (ZTF) will discover 110 and 1
systems per year before the supernova (SN) explosion in the final image
respectively. Systems will be identified days before the
final explosion. We then explore the possibility of performing early-time
observations for Type IIP and Type Ia SNe in LSST-discovered systems. Using a
simulated Type IIP explosion, we predict that the shock breakout in one
trailing image per year will peak at 24.1 mag ( 23.3) in
the -band (), however evolving over a timescale of 30 minutes.
Using an analytic model of Type Ia companion interaction, we find that in the
-band we should observe at least one shock cooling emission event per year
that peaks at 26.3 mag ( 29.6) assuming all Type Ia gLSNe
have a 1 M red giant (main sequence) companion. We perform Bayesian
analysis to investigate how well deep observations with 1 hour exposures on the
European Extremely Large Telescope would discriminate between Type Ia
progenitor populations. We find that if all Type Ia SNe evolved from the
double-degenerate channel, then observations of the lack of early blue flux in
10 (50) trailing images would rule out more than 27% (19%) of the population
having 1 M main sequence companions at 95% confidence.Comment: 17 pages, 15 figures (including appendices). Accepted by MNRAS 3rd
May 202
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Retail cannabis prices in California through legalization, regulation and taxation
Traditional sources of retail price information, such as scanner data and government price surveys, are not available for cannabis. To help fill this gap, between October 2016 and July 2018 the UC Agricultural Issues Center collected online retail price ranges for dried cannabis flower and cannabis-oil cartridges at retailers around California. During this 21-month time period, the legal landscape of the California cannabis market underwent three broad regulatory changes: adult-use decriminalization, licensing and regulation and mandatory testing. This article provides unique primary data on legal cannabis prices in California before and after each of these three changes. Our data are imperfect but do provide a glimpse of the patterns of California cannabis prices at different times. For dried cannabis flower, we observe relatively stable retail prices over the 21-month period at both the top and bottom ends of the price range. For cannabis-oil cartridges, we observe relatively stable prices at the bottom end but increasing prices at the top end between November 2017 and July 2018
Precise time delays from strongly gravitationally lensed type Ia supernovae with chromatically microlensed images
Time delays between the multiple images of strongly gravitationally lensed Type Ia supernovae (glSNe Ia) have the potential to deliver precise cosmological constraints, but the effects of microlensing on time delay extraction have not been studied in detail. Here we quantify the effect of microlensing on the glSN Ia yield of the Large Synoptic Survey Telescope (LSST) and the effect of microlensing on the precision and accuracy of time delays that can be extracted from LSST glSNe Ia. Microlensing has a negligible effect on the LSST glSN Ia yield, but it can be increased by a factor of ∼2 over previous predictions to 930 systems using a novel photometric identification technique based on spectral template fitting. Crucially, the microlensing of glSNe Ia is achromatic until three rest-frame weeks after the explosion, making the early-time color curves microlensing-insensitive time delay indicators. By fitting simulated flux and color observations of microlensed glSNe Ia with their underlying, unlensed spectral templates, we forecast the distribution of absolute time delay error due to microlensing for LSST, which is unbiased at the sub-percent level and peaked at 1% for color curve observations in the achromatic phase, while for light-curve observations it is comparable to state-of-the-art mass modeling uncertainties (4%). About 70% of LSST glSN Ia images should be discovered during the achromatic phase, indicating that microlensing time delay uncertainties can be minimized if prompt multicolor follow-up observations are obtained. Accounting for microlensing, the 1-2 day time delay on the recently discovered glSN Ia iPTF16geu can be measured to 40% precision, limiting its cosmological utility
Costs of cannabis testing compliance: Assessing mandatory testing in the California cannabis market.
Most U.S. states that have regulated and taxed cannabis have imposed some form of mandatory safety testing requirements. In California, the country's largest and oldest legal cannabis market, mandatory testing was first enforced by state regulators in July 2018, and additional mandatory tests were introduced at the end of 2018. All cannabis must be tested and labeled as certified by a state-licensed cannabis testing laboratory before it can be legally marketed in California. Every batch that is sold by licensed retailers must be tested for more than 100 contaminants, including 66 pesticides with tolerance levels lower than the levels allowable for any other agricultural product in California. This paper estimates the costs of compliance with mandatory cannabis testing laws and regulations, using California's testing regime as a case study. We use state government data, data collected from testing laboratories, and data collected from lab equipment suppliers to run a set of Monte Carlo simulations and estimate the cost per pound of compliance with California's new cannabis testing regulations. We find that cost per pound is highly sensitive to average batch size and testing failure rates. We present results under a variety of different assumptions about batch size and failure rates. We also find that under realistic assumptions, the loss of cannabis that must be destroyed if a batch fails testing accounts for a larger share of total testing costs than does the cost of the lab tests. Using our best estimates of average batch size (8 pounds) and failure rate (4%) in the 2019 California market, we estimate testing cost at $136 per pound of dried cannabis flower, or about 10 percent of the reported average wholesale price of legal cannabis in the state. Our findings explain effects of the testing standards on the cost of supplying legal licensed cannabis, in California, other U.S. states, and foreign jurisdictions with similar testing regimes
Single-object Imaging and Spectroscopy to Enhance Dark Energy Science from LSST
Single-object imaging and spectroscopy on telescopes with apertures ranging
from ~4 m to 40 m have the potential to greatly enhance the cosmological
constraints that can be obtained from LSST. Two major cosmological probes will
benefit greatly from LSST follow-up: accurate spectrophotometry for nearby and
distant Type Ia supernovae will expand the cosmological distance lever arm by
unlocking the constraining power of high-z supernovae; and cosmology with time
delays of strongly-lensed supernovae and quasars will require additional
high-cadence imaging to supplement LSST, adaptive optics imaging or
spectroscopy for accurate lens and source positions, and IFU or slit
spectroscopy to measure detailed properties of lens systems. We highlight the
scientific impact of these two science drivers, and discuss how additional
resources will benefit them. For both science cases, LSST will deliver a large
sample of objects over both the wide and deep fields in the LSST survey, but
additional data to characterize both individual systems and overall systematics
will be key to ensuring robust cosmological inference to high redshifts.
Community access to large amounts of natural-seeing imaging on ~2-4 m
telescopes, adaptive optics imaging and spectroscopy on 8-40 m telescopes, and
high-throughput single-target spectroscopy on 4-40 m telescopes will be
necessary for LSST time domain cosmology to reach its full potential. In two
companion white papers we present the additional gains for LSST cosmology that
will come from deep and from wide-field multi-object spectroscopy.Comment: Submitted to the call for Astro2020 science white paper
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Results at 24 months from the prospective, randomized, multicenter Investigational Device Exemption trial of ProDisc-C versus anterior cervical discectomy and fusion with 4-year follow-up and continued access patients.
BackgroundCervical total disk replacement (TDR) is intended to address pain and preserve motion between vertebral bodies in patients with symptomatic cervical disk disease. Two-year follow-up for the ProDisc-C (Synthes USA Products, LLC, West Chester, Pennsylvania) TDR clinical trial showed non-inferiority versus anterior cervical discectomy and fusion (ACDF), showing superiority in many clinical outcomes. We present the 4-year interim follow-up results.MethodsPatients were randomized (1:1) to ProDisc-C (PDC-R) or ACDF. Patients were assessed preoperatively, and postoperatively at 6 weeks and 3, 6, 12, 18, 24, 36, and 48 months. After the randomized portion, continued access (CA) patients also underwent ProDisc-C implantation, with follow-up visits up to 24 months. Evaluations included Neck Disability Index (NDI), Visual Analog Scale (VAS) for pain/satisfaction, and radiographic and physical/neurologic examinations.ResultsRandomized patients (103 PDC-R and 106 ACDF) and 136 CA patients were treated at 13 sites. VAS pain and NDI score improvements from baseline were significant for all patients (P < .0001) but did not differ among groups. VAS satisfaction was higher at all time points for PDC-R versus ACDF patients (P = .0499 at 48 months). The percentage of patients who responded yes to surgery again was 85.6% at 24 months and 88.9% at 48 months in the PDC-R group, 80.9% at 24 months and 81.0% at 48 months in the ACDF group, and 86.3% at 24 months in the CA group. Five PDC-R patients (48 months) and no CA patients (24 months) had index-level bridging bone. By 48 months, approximately 4-fold more ACDF patients required secondary surgery (3 of 103 PDC-R patients [2.9%] vs 12 of 106 ACDF patients [11.3%], P = .0292). Of these, 6 ACDF patients (5.6%) required procedures at adjacent levels. Three CA patients required secondary procedures (24 months).ConclusionsOur 4-year data support that ProDisc-C TDR and ACDF are viable surgical options for symptomatic cervical disk disease. Although ACDF patients may be at higher risk for additional surgical intervention, patients in both groups show good clinical results at longer-term follow-up
Three Essays on the Objective Function in Economics.
This dissertation consists of three largely independent essays. The first finds a significant correlation between the price of crude oil and significant terrorist attacks by groups of Middle Eastern origin against Western nations. In particular, such terrorist attacks are considerably more common after oil prices fall than after they rise. The paper goes on to suggest that a model based on expected utility theory may account for this observation. Agents that are predisposed to comitting terrorist acts – but have not yet done so – may be triggered to act when economic conditions worsen.
The second essay shows that the monetary policies of both the Federal Reserve and the European Central Bank tend to be influenced by the degree of dispersion of unemployment rates across regions. This result is very robust, particularly for the United States. However, the two central banks appear to respond differently to this dispersion. That either bank cares about dispersion at all is surprising, as a result similar to certainty equivalence suggests that – at least in the standard cases – the banks should only be concerned with aggregate measures. We propose two alternative theories that seem, respectively, to be consistent with each bank’s policies.
The third essay outlines a strictly neoclassical economic approach to studying behavior linked to emotions. The paper suggests that by explicitly including emotions as an argument in the utility function, textbook economics can yield some non-obvious insights into some human behaviors. The essay demonstrates the neoclassical technique in a number of different settings, and finds it to be applicable to a wide variety of behavrioral phenomena.
A unifying theme for these papers – and one that is particularly stressed in the third chapter – is that a correct identification of the objective function of economic agents can be vital in trying to explain puzzling phenomena.Ph.D.Public Policy & EconomicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/57701/2/dgoldste_1.pd
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