11,197 research outputs found
The Local Group: The Ultimate Deep Field
Near-field cosmology -- using detailed observations of the Local Group and
its environs to study wide-ranging questions in galaxy formation and dark
matter physics -- has become a mature and rich field over the past decade.
There are lingering concerns, however, that the relatively small size of the
present-day Local Group ( Mpc diameter) imposes insurmountable
sample-variance uncertainties, limiting its broader utility. We consider the
region spanned by the Local Group's progenitors at earlier times and show that
it reaches co-moving Mpc in linear size (a volume of ) at . This size at early cosmic epochs is large enough
to be representative in terms of the matter density and counts of dark matter
halos with . The Local
Group's stellar fossil record traces the cosmic evolution of galaxies with
(reaching
at ) over a region that is comparable to or larger than
the Hubble Ultra-Deep Field (HUDF) for the entire history of the Universe. It
is highly complementary to the HUDF, as it probes much fainter galaxies but
does not contain the intrinsically rarer, brighter sources that are detectable
in the HUDF. Archaeological studies in the Local Group also provide the ability
to trace the evolution of individual galaxies across time as opposed to
evaluating statistical connections between temporally distinct populations. In
the JWST era, resolved stellar populations will probe regions larger than the
HUDF and any deep JWST fields, further enhancing the value of near-field
cosmology.Comment: 6 pages, 5 figures; MNRAS Letters, in pres
Consuming transgenic goats' milk containing the antimicrobial protein lysozyme helps resolve diarrhea in young pigs.
Childhood diarrhea is a significant problem in many developing countries and E. coli is a main causative agent of diarrhea in young children. Lysozyme is an antimicrobial protein highly expressed in human milk, but not ruminant milk, and is thought to help protect breastfeeding children against diarrheal diseases. We hypothesized that consumption of milk from transgenic goats which produce human lysozyme (hLZ-milk) in their milk would accelerate recovery from bacterial-induced diarrhea. Young pigs were used as a model for children and infected with enterotoxigenic E. coli. Once clinical signs of diarrhea developed, pigs were fed hLZ-milk or non-transgenic control goat milk three times a day for two days. Clinical observations and complete blood counts (CBC) were performed. Animals were euthanized and samples collected to assess differences in histology, cytokine expression and bacterial translocation into the mesenteric lymph node. Pigs consuming hLZ-milk recovered from clinical signs of infection faster than pigs consuming control milk, with significantly improved fecal consistency (p = 0.0190) and activity level (p = 0.0350). The CBC analysis showed circulating monocytes (p = 0.0413), neutrophils (p = 0.0219), and lymphocytes (p = 0.0222) returned faster to pre-infection proportions in hLZ-milk fed pigs, while control-fed pigs had significantly higher hematocrit (p = 0.027), indicating continuing dehydration. In the ileum, pigs fed hLZ-milk had significantly lower expression of pro-inflammatory cytokine IL-8 (p = 0.0271), longer intestinal villi (p<0.0001), deeper crypts (p = 0.0053), and a thinner lamina propria (p = 0.0004). These data demonstrate that consumption of hLZ-milk helped pigs recover from infection faster, making hLZ-milk an effective treatment of E. coli-induced diarrhea
Recommended from our members
Day 1. Posters – Sport and Performance
Background: Exercise tests are one of the most commonly used tools within sports science research. Therefore, the reliability of such exercise tests is of critical importance when investigating the efficacy of nutritional, physiological, psychological or training interventions. Purpose: The aim of this experiment was to measure the reliability of a 20 km cycling time trial performance test when performed by mounting the cyclists own bicycle frame on an electronic turbo trainer. Methods: Twenty one male cyclists (age 35 ± 8 y, height 1.82 ± 0.05 m, body mass 80.7 ± 9.0 kg) completed the 20 km time trial on three separate occasions; the initial visit was a habituation trial and was followed by two main trials. All laboratory visits were conducted at the same time of day, following a 24h diet and activity standardisation period, and at least 2 h postprandial. The time trial was completed on a Cyclus2 (RBM Electronic, Germany) ergometer. The cyclists mounted their own bike frames on to the ergometer and the settings on the Cyclus2 were adjusted for each individual bike, ensuring an accurate measurement of distance and performance. During the exercise trial, participants were deprived of any performance information other than distance covered and gear selection; no encouragement was provided by experimenters. Results: There was no order effect of the trials, inclusive of the habituation trial (p = 0.901). There was no significant difference in the time taken to complete the 20 km between trials 1 and 2 (trial 1: 1969 ± 112 s; trial 2: 1975 ± 119 s; p = 0.222). The intra-class correlation between trial 1 and 2 was r = 0.99, with the coefficient of variation being 0.7%. Conclusions: The use of a 20 km cycling time trial, in which the cyclists bicycle frame is mounted on a cycle ergometer, is highly reproducible. Such a test can, therefore, be reliably used to detect changes in performance due to various interventions
Behavioral Economics and Its Meaning for Antitrust Agency Decision Making
Of all fields of regulation in the United States, antitrust law relies most heavily on economics to inform the design and application of legal rules. When drafting antitrust statutes in the late 19th and early 20th centuries, Congress anticipated that courts and enforcement agencies would formulate and adjust operational standards to account for new learning. The field of economics — especially industrial organization economics — would give broad statutory commands much of their analytical content.In principle, the flexibility of U.S. antitrust statutes makes competition policy adaptable and accommodates for upgrades over time. This evolutionary process is only effective if antitrust institutions can identify significant advances in economic learning and refine enforcement policy and doctrine accordingly. Owing to their expertise in economics and law, the two federal antitrust agencies — the Antitrust Division of the Department of Justice (DOJ) and the Federal Trade Commission (FTC) — are crucial instruments of adaptation. The antitrust system’s quality depends on the agencies’ commitment to reassess existing doctrine and policy in light of new developments
Behavioral Economics: Implications for Regulatory Behavior
Behavioral economics (BE) examines the implications for decision-making when actors suffer from biases documented in the psychological literature. This article considers how such biases affect regulatory decisions. The article posits a simple model of a regulator who serves as an agent to a political overseer. The regulator chooses a policy that accounts for the rewards she receives from the political overseer — whose optimal policy is assumed to maximize short-run outputs that garner political support, rather than long-term welfare outcomes — and the weight the regulator puts on the optimal long run policy. Flawed heuristics and myopia are likely to lead regulators to adopt policies closer to the preferences of political overseers than they would otherwise. The incentive structure for regulators is likely to reward those who adopt politically expedient policies, either intentionally (due to a desire to please the political overseer) or accidentally (due to bounded rationality). The article urges that careful thought be given to calls for greater state intervention, especially when those calls seek to correct firm biases. The article proposes measures that focus rewards to regulators on outcomes rather than outputs as a way to help ameliorate regulatory biases
U.S. Convergence with International Competition Norms: Antitrust Law and Public Restraints on Competition
In this Article we focus upon an area in which greater convergence of U.S. policy with the practice of many foreign countries is long overdue: the treatment of public policies that suppress competition. Whereas the European Union (“EU”) and numerous other jurisdictions have taken strong measures to limit restraints imposed by national government authorities and political subdivisions, U.S. antitrust policy in many ways is more tolerant of public restraints upon business rivalry. Since the early twentieth century, Supreme Court doctrines have evolved to grant states and the federal government broad rights to enact laws that restrain competition. Further, individual groups are largely free to lobby for laws designed to erect marketplace barriers, and in many cases to mire their competitors in a morass of governmental processes. Because government action (and private conduct to obtain such action) is challengeable in only relative narrow circumstances, much of the battle takes place in the legislative and regulatory arenas rather than in courts. Accordingly, advocacy is the primary tool available to both public and private enforcers of the U.S. antitrust laws to challenge state-imposed restraints on competition. Although the U.S. competition advocacy program has achieved important success, it is not enough. United States enforcers should stand on equal footing with their EU and other foreign counterparts in being able to challenge state action that threatens competition in the same manner as they can challenge private conduct. In this paper, we describe measures available to competition authorities in the U.S. and other jurisdictions to resist encroachments by government policies on the competitive process. We suggest approaches by which the framework of controls upon anticompetitive government policies could be strengthened in the United States
U.S. Convergence with International Competition Norms: Antitrust Law and Public Restraints on Competition
In this Article we focus upon an area in which greater convergence of U.S. policy with the practice of many foreign countries is long overdue: the treatment of public policies that suppress competition. Whereas the European Union (“EU”) and numerous other jurisdictions have taken strong measures to limit restraints imposed by national government authorities and political subdivisions, U.S. antitrust policy in many ways is more tolerant of public restraints upon business rivalry. Since the early twentieth century, Supreme Court doctrines have evolved to grant states and the federal government broad rights to enact laws that restrain competition. Further, individual groups are largely free to lobby for laws designed to erect marketplace barriers, and in many cases to mire their competitors in a morass of governmental processes. Because government action (and private conduct to obtain such action) is challengeable in only relative narrow circumstances, much of the battle takes place in the legislative and regulatory arenas rather than in courts. Accordingly, advocacy is the primary tool available to both public and private enforcers of the U.S. antitrust laws to challenge state-imposed restraints on competition. Although the U.S. competition advocacy program has achieved important success, it is not enough. United States enforcers should stand on equal footing with their EU and other foreign counterparts in being able to challenge state action that threatens competition in the same manner as they can challenge private conduct. In this paper, we describe measures available to competition authorities in the U.S. and other jurisdictions to resist encroachments by government policies on the competitive process. We suggest approaches by which the framework of controls upon anticompetitive government policies could be strengthened in the United States
Behavioral Economics and Its Meaning for Antitrust Agency Decision Making
Of all fields of regulation in the United States, antitrust law relies most heavily on economics to inform the design and application of legal rules. When drafting antitrust statutes in the late 19th and early 20th centuries, Congress anticipated that courts and enforcement agencies would formulate and adjust operational standards to account for new learning. The field of economics — especially industrial organization economics — would give broad statutory commands much of their analytical content.In principle, the flexibility of U.S. antitrust statutes makes competition policy adaptable and accommodates for upgrades over time. This evolutionary process is only effective if antitrust institutions can identify significant advances in economic learning and refine enforcement policy and doctrine accordingly. Owing to their expertise in economics and law, the two federal antitrust agencies — the Antitrust Division of the Department of Justice (DOJ) and the Federal Trade Commission (FTC) — are crucial instruments of adaptation. The antitrust system’s quality depends on the agencies’ commitment to reassess existing doctrine and policy in light of new developments
Unreasonable: A Strict Liability Solution to the FTC’s Data Security Problem
For over two decades, the FTC creatively employed its capacious statute to police against shoddy data practices. Although the FTC’s actions were arguably needed at the time to fill a gap in enforcement, there are reasons to believe that its current approach has outlived its usefulness and is in serious need of updating. In particular, our analysis shows that the FTC’s current approach to data security is unlikely to instill anything close to optimal incentives for data holders. These shortcomings cannot be fixed through changes to the FTC enforcement approach, as they are largely generated by a mismatch between the tools that Congress gave it over a century ago and what it needs to foster firms’ incentives to mimic socially optimal levels of care for the data they hold. Not only does the current framework likely suffer from informational deficiencies attendant to its focus on “reasonable” security that render liability standards uncertain, it also lacks the ability to obtain the type of relief that will force firms to internalize the costs of their data security decisions. We examine the problem of data security enforcement through the lens of the economics of optimal precautions and identify several reasons why a strict liability regime administered by the FTC, under which firms pay for the expected harm from breaches they cause, is likely to be superior to the current framework that revolves around the concept of reasonableness. The benefits of strict liability flow from the likelihood that firms do not fully internalize the costs and benefits of their data security decisions and the relatively large informational burdens associated with measuring actual and optimal care under a negligence regime. We also show why in this informational environment, strict liability is better than negligence for developing a vibrant cyber insurance market, allowing for data security regulation to be de facto outsourced to insurers who will contract with firms for optimal levels of care. Because these private contracts will harness private information on costs and benefits from precautions, they are likely to incentivize more efficient behavior
- …