The effect of grass genotype and spring management on the nutritive value of mid-summer ryegrass swards

End of project reportThe objective of this project was to investigate the environmental, morphological and management factors that control reproductive initiation and development in Lolium perenne L. (perennial ryegrass) and their influence on mid-season sward quality. These factors were assessed on eight perennial ryegrass cultivars through spaced plant and plot studies. The first part of this project determined the effects of meteorological conditions and latitude on reproductive initiation and ear emergence of cultivars over two consecutive years. It was concluded that the critical day length requirement for reproductive initiation varies between perennial ryegrass cultivars and is independent of latitude and the normal range of conditions. Using this information a strong correlation (r2 = 0.94) was found between the critical day length for ear initiation and the ten year standardised ear emergence dates of the cultivars. This correlation was sufficiently robust to predict the critical initiation date for any perennial ryegrass cultivar on a UK recommended list or on the EU common catalogue by using their heading dates from the UK Plant Breeders Rights trials at Crossnacreevy. Large variation was observed for secondary initiation and re-heading between cultivars of similar and varying maturity, which is a major factor reducing mid-season sward quality. The propensity for initiation of re-heading was strongly influenced by the severity of defoliation (intense to very lax), but there was also evidence to suggest that critical day length post-solstice, may determine the latest date when further reproductive initiation could occur. Differences in plant growth modes were clearly evident as the sward structure, plant morphology and nutritive compositions differed significantly between cultivars during the mid-season. Defoliation management also significantly affected mid-season sward structure, morphology and nutritive composition. While the effect of defoliation height on the sward physical and chemical compositions was inconclusive, an intensive (30 mm) defoliation resulted in plants returning to a vegetative growth mode earlier compared to a lax (60 mm) defoliation treatment. It was observed that defoliation at a critical growth stage can significantly affect subsequent sward structures. Delaying initial spring defoliation resulted in a greater leaf proportion and swards of greater herbage quality in the plot study. This study, therefore, established the need for more detailed evaluation of cultivars by national testing authorities to allow farmers to select cultivars for grazing use that will optimise animal intake and performance

Outcome Prediction in the Practice of Law

Business forecasters typically use time-series models to predict future demands, the forecasts informing management decision making and guiding organizational planning. But this type of forecasting is merely a subset of the broader field of predictive analytics, models used by data scientists in all manner of applications, including credit approvals, fraud detection, product-purchase and music-listening recommendations, and even the real-time decisions made by self-driving vehicles. The practice of law requires decisions that must be based on predictions of future legal outcomes, and data scientists are now developing forecasting methods to support the process. In this article, Mark Osbeck and Mike Gilliland first examine the traditional tools lawyers employ along with the limitations that prevent these tools from consistently delivering accurate predictions. They then describe how new data-science approaches, including AI, are starting to alter the way law firms operate

Improving Productivity of Multiphase Flow Aerobic Oxidation Using a Tube-in-Tube Membrane Contactor

The application of flow reactors in multiphase catalytic reactions represents a promising approach for enhancing the efficiency of this important class of chemical reactions. We developed a simple approach to improve the reactor productivity of multiphase catalytic reactions performed using a flow chemistry unit with a packed bed reactor. Specifically, a tube-in-tube membrane contactor (sparger) integrated in-line with the flow reactor has been successfully applied to the aerobic oxidation of benzyl alcohol to benzaldehyde utilizing a heterogeneous palladium catalyst in the packed bed. We examined the effect of sparger hydrodynamics on reactor productivity quantified by space time yield (STY). Implementation of the sparger, versus segmented flow achieved with the built in gas dosing module (1) increased reactor productivity 4-fold quantified by space time yield while maintaining high selectivity and (2) improved process safety as demonstrated by lower effective operating pressures

Meta-analysis of the effect of white clover inclusion in perennial ryegrass swards on milk production

peer-reviewedThere is increased demand for dairy products worldwide, which is coupled with the realization that consumers want dairy products that are produced in a sustainable and environmentally benign manner. Forage legumes, and white clover (Trifolium repens L.; WC) in particular, have the potential to positively influence the sustainability of pasture-based ruminant production systems. Therefore, there is increased interest in the use of forage legumes because they offer opportunities for sustainable pasture-based production systems. A meta-analysis was undertaken to quantify the milk production response associated with the introduction of WC into perennial ryegrass swards and to investigate the optimal WC content of dairy pastures to increase milk production. Two separate databases were created. In the grass-WC database, papers were selected if they compared milk production of lactating dairy cows grazing perennial ryegrass-WC (GC) swards with that of cows grazing perennial ryegrass-only swards (GO). In the WC-only database, papers were selected if they contained milk production from lactating dairy cows grazing on GC swards with varying levels of WC content. Data from both databases were analyzed using mixed models (PROC MIXED) in SAS (SAS Institute, Cary, NC). Within the grass-WC database, where mean sward WC content was 31.6%, mean daily milk and milk solids yield per cow were increased by 1.4 and 0.12 kg, respectively, whereas milk and milk solids yield per hectare were unaffected when cows grazed GC compared with GO swards. Stocking rate and nitrogen fertilizer application were reduced by 0.25 cows/ha and 81 kg/ha, respectively, on GC swards compared with GO swards. These results highlight the potential of GC production systems to achieve similar levels of production to GO systems but with reduced fertilizer nitrogen inputs, which is beneficial from both an economic and environmental point of view. In the context of increased demand for dairy products, there may be potential to increase the productivity of GC systems by increasing fertilizer nitrogen use to increase stocking rate and carrying capacity while also retaining the benefit of WC inclusion on milk production per cow

Traffic-related air pollution and obesity formation in children: a longitudinal, multilevel analysis.

BackgroundBiologically plausible mechanisms link traffic-related air pollution to metabolic disorders and potentially to obesity. Here we sought to determine whether traffic density and traffic-related air pollution were positively associated with growth in body mass index (BMI = kg/m2) in children aged 5-11 years.MethodsParticipants were drawn from a prospective cohort of children who lived in 13 communities across Southern California (N = 4550). Children were enrolled while attending kindergarten and first grade and followed for 4 years, with height and weight measured annually. Dispersion models were used to estimate exposure to traffic-related air pollution. Multilevel models were used to estimate and test traffic density and traffic pollution related to BMI growth. Data were collected between 2002-2010 and analyzed in 2011-12.ResultsTraffic pollution was positively associated with growth in BMI and was robust to adjustment for many confounders. The effect size in the adjusted model indicated about a 13.6% increase in annual BMI growth when comparing the lowest to the highest tenth percentile of air pollution exposure, which resulted in an increase of nearly 0.4 BMI units on attained BMI at age 10. Traffic density also had a positive association with BMI growth, but this effect was less robust in multivariate models.ConclusionsTraffic pollution was positively associated with growth in BMI in children aged 5-11 years. Traffic pollution may be controlled via emission restrictions; changes in land use that promote jobs-housing balance and use of public transit and hence reduce vehicle miles traveled; promotion of zero emissions vehicles; transit and car-sharing programs; or by limiting high pollution traffic, such as diesel trucks, from residential areas or places where children play outdoors, such as schools and parks. These measures may have beneficial effects in terms of reduced obesity formation in children

Modified Seed Growth of Iron Oxide Nanoparticles in Benzyl Alcohol – Optimization for Heating and Broad Stability in Biomedical Applications

Iron oxide nanoparticles have received sustained interest for biomedical applications as synthetic approaches are continually developed for control of nanoparticle properties. However, many approaches focus solely on the material, rather than the complete optimization of synthesis and functionalization together to enhance translation into biological systems. Presented herein is a modified seed growth method designed for obtaining optimal nanoparticle properties and ease of surface functionalization for long term stability. With a one or two addition process, iron oxide nanoparticles were produced in crystallite sizes ranging from 5-15 nm using only benzyl alcohol and an iron precursor. In the functionalization process, concentration variations were required for stabilizing different nanoparticle sizes. Radio frequency induction heating experiments of various crystallite and hydrodynamic sizes verified that the heating efficiency greatly increased while approaching the 15 nm crystallite, and suggested an important role of the overall particle size on heating efficiency. Initial in vitro experiments with the functionalized nanoparticles showed success in providing hyperthermia-induced tumour cell killing without an increase in the temperature of the cell suspension medium. This demonstrates the potential for nanoparticle-based hyperthermia to provide a therapeutic effect while limiting normal tissue damage

An economic impact comparative analysis of farmers’ markets in Michigan and Ontario

Farmers\u27 markets play a vital role in local economic development by providing a site for local and small business incubation, creating an economic multiplier effect to neighboring businesses, and recycling customer dollars within the community. While several studies have evaluated characteristics of farmers\u27 markets within single metropolitan areas, few have compared the impact of multiple markets in socioeconomically contrasting regions. This research compares shopping habits and economic impacts of customers at farmers\u27 markets in two North American cities: Flint, Michigan, and London, Ontario. Overall, 895 market visitors completed surveys. We conducted statistical and spatial analyses to identify differences between these markets. Though geographically proximate and similar in metropolitan size, the two cities differ greatly in recent economic development, social vitality, and public health indicators. The objectives of this article are to quantify the impact that each market has on its local economy and contextualize these impacts in light of the place-specific attributes of each market. Results indicate that customers come from a mix of urban and suburban locations, but that key urban areas do not draw a substantial share of customers. Marketing efforts in nearby disadvantaged neighborhoods, therefore, might yield new customers and increase multiplier effects within the neighborhoods. The London market drew slightly younger customers who shopped less frequently, while the Flint market drew an older crowd that attended more regularly. This may be attributable to the relative age of the markets, and certainly reflects the marketing push of each market\u27s managers. Given the opportunity to compare similarities and differences, much can be learned from each market in terms of opportunities for marketing, local economic development, and increased community vitality

Dry Matter Yield of Perennial Ryegrass Cultivars under Mechanical Cutting and Animal Grazing

Perennial ryegrass evaluation trials are essential to identifying and promoting the most productive cultivars for use at farm level to maximise sward productivity (Grogan and Gilliland 2011). Cultivar testing is predominantly conducted under simulated grazing trials to predict dry matter yield (DMY) performance under animal grazing. Previous studies have shown a high correlation in DMY between these two defoliation methods (Camlin and Stewart 1975; Creighton et al. 2010). In contrast, Binnie and Chestnutt (1991) demonstrated that swards grazed by animals had higher DMY performance than those exposed to simulated grazing managements. Animal pressures such as pulling, treading and nutrient return are not present in a simulated grazing management. The objective of this study was to determine if a relationship exists between the DMY of perennial ryegrass cultivars exposed to mechanical cutting compared to animal grazing

The Kepler Pixel Response Function

Kepler seeks to detect sequences of transits of Earth-size exoplanets orbiting Solar-like stars. Such transit signals are on the order of 100 ppm. The high photometric precision demanded by Kepler requires detailed knowledge of how the Kepler pixels respond to starlight during a nominal observation. This information is provided by the Kepler pixel response function (PRF), defined as the composite of Kepler's optical point spread function, integrated spacecraft pointing jitter during a nominal cadence and other systematic effects. To provide sub-pixel resolution, the PRF is represented as a piecewise-continuous polynomial on a sub-pixel mesh. This continuous representation allows the prediction of a star's flux value on any pixel given the star's pixel position. The advantages and difficulties of this polynomial representation are discussed, including characterization of spatial variation in the PRF and the smoothing of discontinuities between sub-pixel polynomial patches. On-orbit super-resolution measurements of the PRF across the Kepler field of view are described. Two uses of the PRF are presented: the selection of pixels for each star that maximizes the photometric signal to noise ratio for that star, and PRF-fitted centroids which provide robust and accurate stellar positions on the CCD, primarily used for attitude and plate scale tracking. Good knowledge of the PRF has been a critical component for the successful collection of high-precision photometry by Kepler.Comment: 10 pages, 5 figures, accepted by ApJ Letters. Version accepted for publication

Air Pollution Exposure Assessment for Epidemiologic Studies of Pregnant Women and Children: Lessons Learned from the Centers for Children’s Environmental Health and Disease Prevention Research

The National Children’s Study is considering a wide spectrum of airborne pollutants that are hypothesized to potentially influence pregnancy outcomes, neurodevelopment, asthma, atopy, immune development, obesity, and pubertal development. In this article we summarize six applicable exposure assessment lessons learned from the Centers for Children’s Environmental Health and Disease Prevention Research that may enhance the National Children’s Study: a) Selecting individual study subjects with a wide range of pollution exposure profiles maximizes spatial-scale exposure contrasts for key pollutants of study interest. b) In studies with large sample sizes, long duration, and diverse outcomes and exposures, exposure assessment efforts should rely on modeling to provide estimates for the entire cohort, supported by subject-derived questionnaire data. c) Assessment of some exposures of interest requires individual measurements of exposures using snapshots of personal and microenvironmental exposures over short periods and/or in selected microenvironments. d) Understanding issues of spatial–temporal correlations of air pollutants, the surrogacy of specific pollutants for components of the complex mixture, and the exposure misclassification inherent in exposure estimates is critical in analysis and interpretation. e) “Usual” temporal, spatial, and physical patterns of activity can be used as modifiers of the exposure/outcome relationships. f) Biomarkers of exposure are useful for evaluation of specific exposures that have multiple routes of exposure. If these lessons are applied, the National Children’s Study offers a unique opportunity to assess the adverse effects of air pollution on interrelated health outcomes during the critical early life period