Minimizing the number of independent sets in triangle-free regular graphs

Recently, Davies, Jenssen, Perkins, and Roberts gave a very nice proof of the result (due, in various parts, to Kahn, Galvin-Tetali, and Zhao) that the independence polynomial of a $d$-regular graph is maximized by disjoint copies of $K_{d,d}$. Their proof uses linear programming bounds on the distribution of a cleverly chosen random variable. In this paper, we use this method to give lower bounds on the independence polynomial of regular graphs. We also give new bounds on the number of independent sets in triangle-free regular graphs

Counting dominating sets and related structures in graphs

We consider some problems concerning the maximum number of (strong) dominating sets in a regular graph, and their weighted analogues. Our primary tool is Shearer's entropy lemma. These techniques extend to a reasonably broad class of graph parameters enumerating vertex colorings satisfying conditions on the multiset of colors appearing in (closed) neighborhoods. We also generalize further to enumeration problems for what we call existence homomorphisms. Here our results are substantially less complete, though we do solve some natural problems

On the limits of L1 influence on non-L1 listening: Evidence from Japanese perception of Korean

Language-specific procedures which are efficient for listening to the L1 may be applied to non-native spoken input, often to the detriment of successful listening. However, such misapplications of L1-based listening do not always happen. We propose, based on the results from two experiments in which Japanese listeners detected target sequences in spoken Korean, that an L1 procedure is only triggered if requisite L1 features are present in the input

Beyond the pill: New medication delivery options for ADHD

Successful treatment of pediatric disorders has necessitated the development of alternative medication formulations, as children may prefer alternative dosage forms to tablets or capsules. This is especially true for attention-deficit/hyperactivity disorder (ADHD), which is one of the most common chronic pediatric conditions and often involves children with a variety of overlapping physical, psychological, or neurodevelopmental disorders. A special challenge for developing alternative dosage forms for ADHD treatment is the incorporation of a once-daily long-acting formulation. Traditional ADHD medication formulations have been limited, and issues surrounding prescribed dosing regimens—including poor medication adherence, difficulty swallowing, and the lack of dosing titration options—persist in ADHD treatment. In other disease areas, the development of alternative formulations has provided options for patients who have issues with consuming solid dosage forms, particularly children and individuals with developmental disorders. In the light of these new developments, several alternative formulations for ADHD medications are under development or have recently become available. This article reviews the various strategies for developing alternative dosage forms in other disease areas and discusses the application of these strategies in ADHD treatment. Alternative dosage forms may increase medication adherence, compliance, and patient preference and, therefore, improve the overall treatment for ADHD.</jats:p

Corn Growing in Ohio

Exact date of bulletin unknown.PDF pages: 2

Discrimination of unique biological communities in the Mississippi lignite belt

Small scale hardcopy LANDSAT prints were manually interpreted and color infrared aerial photography was obtained in an effort to identify and map large contiguous areas of old growth hardwood stands within Mississippi's lignite belt which do not exhibit signs of recent disturbance by agriculture, grazing, timber harvesting, fire, or any natural catastrophe, and which may, therefore, contain unique or historical ecological habitat types. An information system using land cover classes derived from digital LANDSAT data and containing information on geology, hydrology, soils, and cultural activities was developed. Using computer-assisted land cover classifications, all hardwood remnants in the study area which are subject to possible disturbance from surface mining were determined. Twelve rare plants were also identified by botanists

Coping with speaker-related variation via abstract phonemic categories

Listeners can cope with considerable variation in the way that different speakers talk. We argue here that they can do so because of a process of phonological abstraction in the speech-recognition system. We review evidence that listeners adjust the bounds of phonemic categories after only very limited exposure to a deviant realisation of a given phoneme. This learning can be talker-specific and is stable over time; further, the learning generalizes to previously unheard words containing the deviant phoneme. Together these results suggest that the learning involves adjustment of prelexical phonemic representations which mediate between the speech signal and the mental lexicon during word recognition. We argue that such an abstraction process is inconsistent with claims made by some recent models of language processing that the mental lexicon consists solely of multiple detailed traces of acoustic episodes. Simulations with a purely episodic model without functional prelexical abstraction confirm that such a model cannot account for the evidence on lexical generalization of perceptual learning. We conclude that abstract phonemic categories form a necessary part of lexical access, and that the ability to store talker-specific knowledge about those categories provides listeners with the means to deal with cross-talker variation

The Anatomy of Health Insurance

This article describes the anatomy of health insurance. It begins by considering the optimal design of health insurance policies. Such policies must make tradeoffs appropriately between risk sharing on the one hand and agency problems such as moral hazard (the incentive of people to seek more care when they are insured) and supplier-induced demand (the incentive of physicians to provide more care when they are well reimbursed) on the other. Optimal coinsurance arrangements make patients pay for care up to the point where the marginal gains from less risk sharing are just offset by the marginal benefits from less wasteful care being provided. Empirical evidence shows that both moral hazard and demand-inducement are quantitatively important. Coinsurance based on expenditure is a crude control mechanism. Moreover, it places no direct incentives on physicians, who are responsible for most expenditure decisions. To place such incentives on physicians is the goal of supply-side cost containment measures, such as utilization review and capitation. This goal motivates the surge in managed care in the United States, which unites the functions of insurance and provision, and allows for active management of the care that is delivered. The analysis then turns to the operation of health insurance markets. Economists generally favor choice in health insurance for the same reasons they favor choice in other markets: choice allows people to opt for the plan that is best for them and encourages plans to provide services efficiently. But choice in health insurance is a mixed blessing because of adverse selection -- the tendency for the sick to choose more generous insurance than the healthy. When sick and healthy enroll in different plans, plans disproportionately composed of poor risks have to charge more than they would if they insured an average mix of people. The resulting high premiums create two adverse effects: they discourage those who are healthier but would prefer generous care from enrolling in those plans (because the premiums are so high), and they encourage plans to adopt measures that deter the sick from enrolling (to reduce their overall costs). The welfare losses from adverse selection are large in practice. Added to them are further losses from having premiums vary with observable health status. Because insurance is contracted for annually, people are denied a valuable form of intertemporal insurance -- the right to buy health coverage at average rates in the future should they get sick today. As the ability to predict future health status increases, the lack of intertemporal insurance will become more problematic. The article concludes by relating health insurance to the central goal of medical care expenditures - better health. Studies to date are not clear on which approaches to health insurance promote health in the most cost-efficient manner. Resolving this question is the central policy concern in health economics.