2,582 research outputs found
Investigating the Potential of Fee-Based Recreation on Private Lands in the Lower Mississippi River Delta
Private landowners may be willing to allow public access for fee-based wildlife-associated recreation. A survey and econometric techniques are proposed to determine what characteristics may influence the probability to decide to offer recreation, what organizational form landowners may prefer to manage and market fee-based recreation, and how liability concerns and other possible disincentives collectively influence landowners' access decisions.wildlife-associated recreation, liability perceptions, Resource /Energy Economics and Policy,
The Organizational Evolution of Markets for Wood Products in the Southern United States
This paper represents the first case study attempt to develop a transaction cost conceptual model to describe industry evolution of the paper and lumber industries in the Southern United States around the late 1800s and early 1900s. We use transaction cost theory to explain the co-evolution of markets for wood products noting that variation in the level and type of investments made in physical and human capital assets needed to manage paper and lumber miller operations had a significant influence on the use of wood dealer systems compared to more vertically organized business arrangements. We identify some testable hypotheses and areas of future research.Industry Evolution, Contracting, Property Rights, Vertical Integration, Forest Products, Industrial Organization, Research Methods/ Statistical Methods, L14, L24, L73, J24,
Feasibility of recruitment to an oral dysplasia trial in the United Kingdom
Background:
Oral epithelial dysplasia (OED) has a malignant potential. Therapeutic options for OED remain both limited and without good evidence. Despite surgery being the most common method of treating OED, recurrence and potentially significant morbidity remain problematic. Consequently, there has been much interest in non-surgical treatments for OED. Cyclo-oxygenase (COX) up-regulation is known to occur in the dysplasia-carcinoma sequence and evidence now exists that COX-2 is a prognostic marker of malignant transformation in OED. COX-inhibitors are therefore considered a potential therapeutic strategy for treating this condition. We aimed to provide both proof of principal evidence supporting the effect of topical COX inhibition, and determine the feasibility of recruitment to an OED chemoprevention trial in the UK.
Methods:
Recruitment of 40 patients with oral leukoplakia to 4 study arms was planned. The total daily dose of Aspirin would increase in each group and be used in the period between initial diagnostic and follow-up biopsies.
Results:
During the 15-month recruitment period, 15/50 screened patients were eligible for recruitment, and 13 (87%) consented. Only 1 had OED diagnosed on biopsy. 16 patients were intolerant of, or already taking Aspirin and 16 patients required no biopsy. Initial recruitment was slow, as detection relied on clinicians identifying potentially eligible patients. Pre-screening new patient letters and directly contacting patients listed for biopsies improved screening of potentially eligible patients. However, as the incidence of OED was so low, it had little impact on trial recruitment. The trial was terminated, as recruitment was unlikely to be achieved in a single centre.
Conclusion:
This feasibility trial has demonstrated the low incidence of OED in the UK and the difficulties in conducting a study because of this. With an incidence of around 1.5/100,000/year and a high proportion of those patients already taking or intolerant of Aspirin, a large multi-centred trial would be required to fulfil the recruitment for this study. The ability of topical non-steroidal anti-inflammatory drugs to modify COX and prostaglandin expression remains an important but unanswered question. Collaboration with centres in other parts of the world with higher incidences of the disease may be required to ensure adequate recruitment.
ISRCTN: 31503555
An Analysis of Rank Ordered Data
Many methods are available to analyze rank ordered data. We used a spectral density method to analyze Formosan subterranean termite control options ranked by Louisiana homeowners. Respondents are asked to rank termite control options from the most preferred to the least preferred option. Spectral analysis results indicated that the most preferred termite control choice is a relatively cheap ($0.13 per square foot) option of liquid treatment.FST, rank ordered data, spectral analysis, Research Methods/ Statistical Methods,
The Role of Local Policies on Resource Utilization: Timber Harvesting in St. Tammany Parish, Louisiana
Seemingly unrelated regression was used to investigate if the passage of forestry-related ordinances has had an effect upon timber harvesting activities in St. Tammany Parish, Louisiana. Results indicate that a significant negative relationship exists between a $10,000 road bond ordinance and the level of timber harvest in the Parish.Resource /Energy Economics and Policy,
The smash product for derived categories in stable homotopy theory
An E_1 (or A-infinity) ring spectrum R has a derived category of modules D_R.
An E_2 structure on R endows D_R with a monoidal product. An E_3 structure on R
endows the monoidal product with a braiding. If the E_3 structure extends to an
E_4 structure then the braided monoidal product is symmetric monoidal.Comment: Minor correction
Tilings of Annular Region
We present our summer research on mathematical tiling. We classified which rectangular annular regions are tileable by the set of T and skew tretrominoes. We present a partial proof of this result, and discuss some of the context for this problem
Competitive Tiling
Competitive tiling consists of two players, a tile set, a region, and a non-negative integer d. Alice and Bob, our two players, alternate placing tiles on the untiled squares of the region. They play until no more tiles can be placed. Alice wins if at most d squares are untiled at the end of the game, and Bob wins if more than d squares are untiled. For given regions and tile sets we are interested in the smallest value of d such that Alice has a winning strategy. We call this the game tiling number. In this project, we focus on finding the game tiling number for the game played with dominoes on 2 x n rectangles, modified 2 x n rectangles, and rectangular annular regions
Vibronic interactions in the visible and near-infrared spectra of C60− anions
Electron-phonon coupling is an important factor in understanding many properties of the C60 fullerides. However, there has been little success in quantifying the strength of the vibronic coupling in C60 ions, with considerable disagreement between experimental and theoretical results. We will show that neglect of quadratic coupling in previous models for C60- ions results in a significant overestimate of the linear coupling constants. Including quadratic coupling allows a coherent interpretation to be made of earlier experimental and theoretical results which at first sight are incompatible
A Facilitated Prioritization Process: An Application in the Forest Sector in Honduras
This article describes an application of an Extension-oriented facilitated goal prioritization process conduced for national forest sector development in Honduras. The process can be employed in many settings that require stakeholder input. This article describes the consensus ranking of priority actions and generation of most doable actions. The results of this project will be used as an input in national forest-sector strategic planning in Honduras
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