SMALL FARMS AND SUSTAINABLE DEVELOPMENT: IS SMALL MORE SUSTAINABLE?

A new, post-industrial, paradigm for agriculture is emerging under the concept of sustainable agriculture. The sustainability paradigm has emerged to solve problems created by the industrial model, primarily environmental pollution and resource base degradation. The role of farm size in this transformation to a more sustainable agriculture is the issue addressed. Using a descriptive approach, and relying on a survey of the literature including emerging paradigms and observations, we conclude that, from a sustainability perspective, the smallest effective size will be the most competitive size for farms, as for other knowledge-based enterprises of the future.Agriculture, Farm size, Paradigms, Sustainability, Environmental Economics and Policy, Farm Management,

TRADING POULTRY LITTER AT THE WATERSHED LEVEL : A GOAL FOCUSING APPLICATION

We explore the transfer of poultry litter among watersheds incorporating both economic characteristics (litter demand and supply) and environmental characteristics (vulnerability to phosphorus runoff, a major pollutant). A combination of techniques was employed: the Lemunyon-Gilbert P-Index model to determine watershed environmental vulnerability, GIS for land use coverages, and a goal focusing model (incorporating Saaty's eigen-value approach for penalty weight estimation) to identify optimal litter shipments among watersheds. Both primary and secondary data were used. The results should be useful to producers and policy makers in the study area and in other areas where poultry production is linked to water quality, and contribute to a more sustainable poultry sector.Livestock Production/Industries,

MODELING STATE AGRICULTURE: AN APPLICATION AND SOME IMPLICATIONS

A disaggregated econometric model of the agricultural sector at the state level is constructed. Using time series data on West Virginia agriculture and three-stage least squares in estimation, the model is employed to examine how various components of the state's agricultural sector adjust to changes in certain price and nonprice variables. Results reveal characteristics of the state's agricultural economy that are both unique and useful - characteristics that are usually masked in aggregate models but that have profound implications for modeling producer decision making and policy formulation.Industrial Organization,

FACTORS AFFECTING THE ADOPTION OF SUSTAINABLE AGRICULTURAL PRACTICES

The extent to which individual factors influence the adoption of sustainable agricultural practices is estimated using a logit model and data from a 1990 survey of West Virginia producers. The results are, as expected, different than those for conventional agricultural technologies. For example, the effects of human capital characteristics are significant, while those for structural and institutional characteristics are not. However, the likelihood of adoption of sustainable agricultural practices is affected most by the environmental characteristic of whether or not the producer is aware that ground water contamination exists on his farm. This creates an important "awareness effect" upon which policies to promote sustainable agriculture adoption can be formulated. It also implies the existence of a derived demand for sustainable agriculture.Farm Management,

THE INVESTMENT POTENTIAL OF WARM-SEASON GRASSES FOR HILL-LAND BEEF PRODUCERS

The investment potential of warm-season grasses is compared with that of cool-season grasses, with special emphasis on hill-land beef production. In addition to evaluating relative costs and returns for various grazing systems, a sensitivity analysis is conducted. The results are then illustrated for a representative hill-land farm in West Virginia, and both an optimal and a set of quasi-optimal solutions are generated within the linear programming framework. In general, warm-season grasses are found to be a superior investment alternative for hill-land beef producers.Livestock Production/Industries,

Differences among Watershed Sub-Populations in Willingness to Pay for Water Quality Improvements: The Impact of TMDL Development

The Opequon watershed is located in northern Virginia (VA) and the eastern panhandle of West Virginia (WV). In both states, Opequon Creek is classified as impaired based on violations of bacteria, benthic and biologic standards. Both VA and WV are using Total Maximum Daily Load (TMDL) plans to improve water quality within Opequon Creek. However, these TMDL plans are at different stages with VA being completed and WV still in progress. As part of the TMDL process in VA, this research is based on a contingent valuation survey which was developed to measure the expected monetary benefits of TMDL implementation throughout the Opequon watershed. On the basis of log-likelihood tests of grouped tobit models to explain willingness-to-pay (WTP) for watershed clean-up, VA, WV, and VA riparian landowner respondents were found to consist of different populations. Riparian landowners had the highest median annual WTP at $64, VA respondents the next highest ($49), and WV the lowest ($32). These medians were found to be statistically different from each other. When valuing out-of-state clean-up, however, VA and WV respondents were found to be similar populations with a one-time median WTP of$28. Results show that the TMDL process did impact VA respondent WTP for in-state clean-up.Resource /Energy Economics and Policy,

AN ECONOMIC ANALYSIS OF PASTURE-RAISED BEEF SYSTEMS IN APPALACHIA

Cow-calf operations are important enterprises for family farmers in Appalachia and provide significant opportunity for supplemental income. This analysis constitutes a thorough economic assessment of pasture-raised beef production, an alternative to traditional production that could benefit the region's producers in terms of profitability and mitigated risk. Stochastic budgeting was utilized for profitability and risk comparison between traditional and pasture-raised operations and accounted for seasonal variability in prices, pasture availability and animal performance. Pasture-raised systems, in relation to traditional ones, were shown to consistently yield higher returns over variable costs and were shown less likely to yield losses over total costs in typical production seasons. Economic risk for pasture-raised producers stems largely from production factors but, overall, is seemingly less pronounced than the market risk faced by traditional producers selling live cattle.Farm Management,

TRADING POULTRY LITTER AT THE WATERSHED LEVEL: A GOAL FOCUSING APPLICATION

We explore the transfer of poultry litter among watersheds incorporating both economic and environmental characteristics, and using a goal focusing approach. The results should be useful to producers and policy makers in the study area and in other areas where poultry production is linked to water quality, and contribute to a more sustainable poultry sector.Environmental Economics and Policy, Livestock Production/Industries,

Common Genetic Polymorphisms Influence Blood Biomarker Measurements in COPD

Implementing precision medicine for complex diseases such as chronic obstructive lung disease (COPD) will require extensive use of biomarkers and an in-depth understanding of how genetic, epigenetic, and environmental variations contribute to phenotypic diversity and disease progression. A meta-analysis from two large cohorts of current and former smokers with and without COPD [SPIROMICS (N = 750); COPDGene (N = 590)] was used to identify single nucleotide polymorphisms (SNPs) associated with measurement of 88 blood proteins (protein quantitative trait loci; pQTLs). PQTLs consistently replicated between the two cohorts. Features of pQTLs were compared to previously reported expression QTLs (eQTLs). Inference of causal relations of pQTL genotypes, biomarker measurements, and four clinical COPD phenotypes (airflow obstruction, emphysema, exacerbation history, and chronic bronchitis) were explored using conditional independence tests. We identified 527 highly significant (p 10% of measured variation in 13 protein biomarkers, with a single SNP (rs7041; p = 10−392) explaining 71%-75% of the measured variation in vitamin D binding protein (gene = GC). Some of these pQTLs [e.g., pQTLs for VDBP, sRAGE (gene = AGER), surfactant protein D (gene = SFTPD), and TNFRSF10C] have been previously associated with COPD phenotypes. Most pQTLs were local (cis), but distant (trans) pQTL SNPs in the ABO blood group locus were the top pQTL SNPs for five proteins. The inclusion of pQTL SNPs improved the clinical predictive value for the established association of sRAGE and emphysema, and the explanation of variance (R2) for emphysema improved from 0.3 to 0.4 when the pQTL SNP was included in the model along with clinical covariates. Causal modeling provided insight into specific pQTL-disease relationships for airflow obstruction and emphysema. In conclusion, given the frequency of highly significant local pQTLs, the large amount of variance potentially explained by pQTL, and the differences observed between pQTLs and eQTLs SNPs, we recommend that protein biomarker-disease association studies take into account the potential effect of common local SNPs and that pQTLs be integrated along with eQTLs to uncover disease mechanisms. Large-scale blood biomarker studies would also benefit from close attention to the ABO blood group

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability