680 research outputs found
Don\u27t Bury the Competition: The Growth of Occupational Licensing and a Toolbox for Reform
In recent years, states have subjected more occupations to burdensome regulatory requirements that are often imposed to fetter competition. There is broad agreement that many such restrictions reduce consumer welfare and impose particular burdens on economically disadvantaged groups. This Note examines why existing tools have failed to constrain this protectionist trend. Drawing upon U.S. and foreign experiences, it proposes a statutory reform that would preserve states\u27 roles as primary regulators of occupations subject only to limited FTC oversight to prevent protectionism and that includes numerous procedural protections to avoid excessive preemption
Osteopenic Disease in Growing Pigs: Diagnostic Methods Using Serum and Urine Calcium and Phosphorus Values, Parathormone Assay, and Bone Analysis
This research was performed to evaluate the utility of several serum and urine parameters as well as bone ash and plasma parathormone assay to diagnose and monitor diet-related osteopenia in growing pigs. Five diets were tested as follows: calcium-deficient, phosphorus-replete; moderate-deficiency of calcium and phosphorus; marked deficiency of calcium and phosphorus; calcium replete, phosphorus deficient; and vitamin D deficient. Parameters monitored included serum calcium and phosphorus as well as ratios of urine calcium to creatinine, phosphorus to creatinine, calcium to phosphorus, and percent fractional excretions of calcium and phosphorus. Plasma parathormone (PTH) levels were monitored in 2 of 3 experiments. Osteopenic bone differences at necropsy were evaluated by bone density, percent ash, ash per milliliter bone, calcium per milliliter bone, and phosphorus per milliliter bone. Marked change in urine mineral parameters, especially the calcium-to-phosphorus ratio, typically occurred within 1 to 2 days of treatment and preceded significant change in serum mineral or plasma PTH by 2 to 3 weeks. When monitored, plasma PTH levels were elevated following treatment, which confirms the hyperparathyroid state induced by the test diets. Significant differences in bone mineralization between control and treatment diets at necropsy were generally observed. The results of this study indicate that the analysis of urine minerals offers an early, noninvasive technique to investigate diet-associated osteopenic disease in growing pigs, which can be supported further by bone mineral analysis at postmortem using techniques herein described. Several urine mineral reference intervals for application to field investigations are included. Research into application of similar techniques to evaluate calcium and phosphorus homeostasis in pigs of all ages, including gestating and lactating gilts and sows, appears warranted
The price-volume relationship for new and remanufactured smartphones
Despite the rapid expansion of secondary markets for remanufactured electronic goods, the understanding of their empirical dynamics such as the price-volume relationship is still rather limited. In this study, we investigate such dynamics over time for new, manufacturer- and seller-refurbished smartphones using data from eBay UK and eBay US. We find significant negative relationships between price and volume for new smartphones indicating that the profit potential of such markets for sellers is limited. We show, instead, that the price-volume relationships for remanufactured smartphones are positive and significant – suggesting that the secondary markets for such items are potentially highly profitable. Overall, our empirical results suggest that the UK markets have higher profit potential than their US counterparts. The proposed analysis is a further step toward a better understanding of the price dynamics of new and remanufactured smartphones – and it enables both manufacturers and OEMs to better evaluate the profit potential of one of the fastest growing segments of consumer electronic goods
Possible AGN Shock Heating in the Cool Core Galaxy Cluster Abell 478
We present a detailed X-ray study of the intracluster medium (ICM) of the
nearby, cool-core galaxy cluster Abell 478, with Chandra and XMM observations.
Using a wavelet smoothing hardness analysis, we derive detailed temperature
maps of A478, revealing a surprising amount of temperature structure. The broad
band Chandra spectral fits yield temperatures which are significantly hotter
than those from XMM, but the Fe ionization temperature shows good agreement. We
show that the temperature discrepancy is slightly reduced when comparing
spectra from regions selected to enclose nearly isothermal gas. However, by
simulating multi-temperature spectra and fitting them with a single temperature
model, we find no significant difference between Chandra and XMM, indicating
that non-isothermality cannot fully explain the discrepancy. We have discovered
4 hot spots located between 30--50 kpc from the cluster center, where the gas
temperature is roughly a factor of 2 higher than in the surrounding material.
We estimate the combined excess thermal energy present in these hot spots to be
(3+/-1)x10^59 erg. The location of and amount of excess energy present in the
hot spots are suggestive of a common origin within the cluster core, which
hosts an active galactic nucleus. This cluster also possesses a pair of X-ray
cavities coincident with weak radio lobes, as reported in a previous analysis,
with an associated energy <10% of the thermal excess in the hot spots. The
presence of these hot spots could indicate strong-shock heating of the ICM from
the central radio source -- one of the first such detections in a cool core
cluster. We also probe the mass distribution in the core and find it to be
characterized by a logarithmic slope of -0.35+/-0.22, which is significantly
flatter than an NFW cusp of -1. (abridged)Comment: 15 pages, 15 figures; extra section on simulating effect of
multiphase gas, plus some restructuring of discussion section. Accepted by
ApJ; corrected typo in equation
Paddlefish buccal flow velocity during ram suspension feeding and ram ventilation
A micro-thermistor probe was inserted into the buccal cavity of freely swimming paddlefish to measure flow velocity during ram ventilation, ram suspension feeding and prey processing. Swimming speed was measured from videotapes recorded simultaneously with the buccal flow velocity measurements. Both swimming velocity and buccal flow velocity were significantly higher during suspension feeding than during ram ventilation. As the paddlefish shifted from ventilation to feeding, buccal flow velocity increased to approximately 60 % of the swimming velocity. During prey processing, buccal flow velocity was significantly higher than the swimming velocity, indicating that prey processing involves the generation of suction. The Reynolds number (Re) for flow at the level of the paddlefish gill rakers during feeding is about 30, an order of magnitude lower than the Re calculated previously for pump suspension-feeding blackfish. These data, combined with data available from the literature, indicate that the gill rakers of ram suspension-feeding teleost fishes may operate at a substantially lower Re than the rakers of pump suspension feeders
What's Needed to Develop Strategic Purchasing in Healthcare?:Policy Lessons from a Realist Review
1059-17 Prolongation of atrial effective refractory period by biatrial subthreshold stimulation
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