Soil P Status and Nitrogen Fixation on Organic Dairy Farms in Ontario and Nova Scotia

Legumes are a key source of nitrogen (N) in organic production systems. However, there is evidence that reduced inputs may be leading to deficient soil phosphorus (P) on some organic dairy farms (Roberts et. al. 2008). This may affect crop performance and N fixation in forage legumes. This study aims to gauge the relationship between soil P dynamics in organic dairy systems and legume biological nitrogen fixation (BNF). The study has two main sub-projects: 1. A field survey of soil-test P and legume forage productivity and N fixation on dairy farms in Ontario and Nova Scotia, Canada. 2. Growth chamber and greenhouse studies examining: a) The role of P nutrition in legume growth and N fixation, and b) The P-supplying power of composts, struvite, and a rock P source. Field data was commenced in the 2008 season, and was completed in 2009. Growth chamber and greenhouse studies were conducted in 2009. Analyses of 2009 samples are not complete at the report date

Evaluating the Efficacy of a Dedicated Last Planner® System Facilitator to Enhance Construction Productivity

Construction unknowingly plans for poor levels of productivity with substantial waste, inefficiency, and rework stemming from a proliferation of non-value-adding activities embedded within traditional delivery processes. This approach negatively influences construction’s economic and environmental sustainability. Last Planner® System (LPS) is a key tool of Lean Construction (LC) and is lauded as a value-add process that prioritises flow efficiency by addressing workflow variability and waste elimination on construction projects. This research evaluates how the presence of a dedicated knowledgeable and competent LPS Facilitator, enabling a complete LPS implementation, contributes to improved construction flow, efficiency, and productivity. The study adopted a mixed-methods approach utilising case study design and data collected from a literature review, site observation diary, site documentation analysis, and semi-structured interviews. Limitations exist around small survey size, lack of generalisability, and potential bias of researchers. Findings posit considerable productivity increase; more reliable, predictable, and stable workflow; enhanced team collaboration; as well as accrual of safety, quality, cost, and schedule benefits. Embedding a knowledgeable and competent LPS Facilitator appears to assist successful implementation of LPS with sectoral and societal value-add opportunities. &nbsp

CANADA’S ORGANIC SCIENCE CLUSTER: SCIENCE WITH IMPACT FOR PROFITABILITY, SUSTAINABILITY AND COMPETITIVENESS

In this paper we provide an overview of the goals and potential benefits of a national science program for organic agriculture in Canada from 2013-2018 (application currently under review). The “Organic Science Cluster II (OSCII): Science With Impact for Profitability, Sustainability and Competitiveness” is linked with Canada’s Organic Value Chain Roundtable, the think tank addressing priorities for increasing capacity and market development for organic. OSCII will increase competitiveness by addressing barriers that are constraining production and by capturing new market opportunities such as emerging crops, aquaculture, and ornamental horticulture. OSCII will be coordinated and managed by the Organic Agriculture Centre of Canada at Dalhousie University’s Faculty of Agriculture on behalf of the industry applicant, the Organic Federation of Canada (OFC)

The Crisis in Legal Education: Dabbling in Disaster Planning

The legal education crisis has already struck for many recent law school graduates, signaling potential disaster for law schools already struggling with their own economic challenges. Law schools have high fixed costs caused by competition between schools, the unchecked expansion of federal loan programs, a widely exploited information asymmetry about graduate employment outcomes, and a lack of financial discipline masquerading as innovation. As a result, tuition is up, jobs are down, and skepticism of the value of a J.D. has never been higher. If these trends do not reverse course, droves of students will continue to graduate with debt that greatly reduces their ability to fulfill the law school graduate\u27s traditional and important role in American society. The point at which the law school crisis becomes a disaster for legal education is debatable, but the importance of preparing for and forestalling this disaster is not. This Article serves two forward-looking purposes that stem from the premise that American legal education requires structural change to reduce the cost of obtaining a legal education. First, we set a framework for thinking about reforms to the method of delivering legal education. Second, we examine three blueprints for structural reform: one that has already been implemented and is ineffective, and two that set the discussion on the right track. These blueprints reject mere tinkering in favor of refocusing the attention of legal education stakeholders on the drastic structural changes needed to provide quality, affordable legal education. While we provide only a starting point for considering how the two new models could work in principle, they serve as an intellectual blueprint that can pave the way for new and better ideas about legal education. It is clear that cost reform is necessary, and it is likely that substantial reform is coming. The shape of this reform depends on who gets involved, who we hope include actors beyond those who have set legal education on a path toward disaster

Bilan phosphore du sol et fixation de l'azote dans fermes laitières biologiques de l'Ontario et de la Nouvelle-Écosse

Les légumineuses sont une source importante d'azote (N) en production biologique. Toutefois, il est prouvé que de trop faibles intrants peuvent entraîner une carence de phosphore du sol (P) dans les fermes laitières biologiques (Roberts et coll., 2008), et une réduction possible du rendement des cultures et de la fixation de N par les légumineuses fourragères. La présente étude vise à évaluer le lien entre la dynamique du P du sol et la fixation de l’azote par les légumineuses en gestion biologique (BNF). L’étude a deux principaux sous-projets : 1. Étude sur le terrain de la concentration du P dans le sol, et rendement des légumineuses fourragères et fixation de N dans les fermes laitières de l’Ontario et de la Nouvelle-Écosse, Canada. 2. Études en chambre de culture et en serre du : a) Rôle nutritif du P dans la croissance des légumineuses et dans la fixation de N. b) Taux d’apport de P des composts, de la struvite et d’une source de phosphate naturel. La cueillette de données sur le terrain, commencée à la saison 2008, a été complétée en 2009. Les études en chambre de croissance et en serre ont été menées en 2009. À la remise du rapport, les analyses des échantillons de 2009 ne sont pas terminées

Gene expression profiling of microglia infected by a highly neurovirulent murine leukemia virus: implications for neuropathogenesis

BACKGROUND: Certain murine leukemia viruses (MLVs) are capable of inducing progressive spongiform motor neuron disease in susceptible mice upon infection of the central nervous system (CNS). The major CNS parenchymal target of these neurovirulent retroviruses (NVs) are the microglia, whose infection is largely coincident with neuropathological changes. Despite this close association, the role of microglial infection in disease induction is still unknown. In this paper, we investigate the interaction of the highly virulent MLV, FrCasE, with microglia ex vivo to evaluate whether infection induces specific changes that could account for neurodegeneration. Specifically, we compared microglia infected with FrCasE, a related non-neurovirulent virus (NN) F43/Fr57E, or mock-infected, both at a basic virological level, and at the level of cellular gene expression using quantitative real time RT-PCR (qRT-PCR) and Afffymetrix 430A mouse gene chips. RESULTS: Basic virological comparison of NN, NV, and mock-infected microglia in culture did not reveal differences in virus expression that provided insight into neuropathogenesis. Therefore, microglial analysis was extended to ER stress gene induction based on previous experiments demonstrating ER stress induction in NV-infected mouse brains and cultured fibroblasts. Analysis of message levels for the ER stress genes BiP (grp78), CHOP (Gadd153), calreticulin, and grp58 in cultured microglia, and BiP and CHOP in microglia enriched fractions from infected mouse brains, indicated that FrCasE infection did not induce these ER stress genes either in vitro or in vivo. To broadly identify physiological changes resulting from NV infection of microglia in vitro, we undertook a gene array screen of more than 14,000 well-characterized murine genes and expressed sequence tags (ESTs). This analysis revealed only a small set of gene expression changes between infected and uninfected cells (<18). Remarkably, gene array comparison of NN- and NV-infected microglia revealed only 3 apparent gene expression differences. Validation experiments for these genes by Taqman real-time RT-PCR indicated that only single Ig IL-1 receptor related protein (SIGIRR) transcript was consistently altered in culture; however, SIGIRR changes were not observed in enriched microglial fractions from infected brains. CONCLUSION: The results from this study indicate that infection of microglia by the highly neurovirulent virus, FrCasE, does not induce overt physiological changes in this cell type when assessed ex vivo. In particular, NV does not induce microglial ER stress and thus, FrCasE-associated CNS ER stress likely results from NV interactions with another cell type or from neurodegeneration directly. The lack of NV-induced microglial gene expression changes suggests that FrCasE either affects properties unique to microglia in situ, alters the expression of microglial genes not represented in this survey, or affects microglial cellular processes at a post-transcriptional level. Alternatively, NV-infected microglia may simply serve as an unaffected conduit for persistent dissemination of virus to other neural cells where they produce acute neuropathogenic effects

Optimization of protein recovery from bovine lung by pH shift process using response surface methodology

peer-reviewedBACKGROUND Response surface methodology (RSM) was used in a sequential manner to optimize solubilization and precipitation conditions in the recovery of protein from bovine lung using pH shift. RESULTS Separate D‐optimal designs were employed for protein solubilization and precipitation. Independent variables investigated for protein solubilization were time (10–120 min), temperature (4–20 °C), pH (8.0–11.0) and solvent/sample ratio (2.5–10). Variables for protein precipitation were time (0–60 min) and pH (4.25–6.00). Soluble protein yields ranged from 323 to 649 g kg−1 and the quadratic model for protein solubilization revealed a coefficient of determination R2 of 0.9958. Optimal conditions for maximum protein solubility were extraction time 140 min, temperature 19 °C, pH 10.8 and solvent/sample ratio 13.02. Protein precipitation yields varied from 407 to 667 g kg−1, giving a coefficient of determination R2 of 0.9335. Optimal conditions for maximum protein precipitation were pH 5.03 and 60 min. Based on the RSM model, solubilization conditions were manipulated to maximize protein solubilization under reduced water and alkaline usage. These conditions were also validated. CONCLUSION Models for solubilization and precipitation using bovine and porcine lung were validated; predicted and actual yields were in good agreement, showing cross‐species applicability of the results. © 2017 Society of Chemical Industr

SUSTAINABILITY OF ORGANIC DAIRYING IN CANADA

The distinctive production characteristics and economic performance of organic dairy farms in central Canada has been documented, but the sustainability of these systems with respect to farm nutrient flows is less well understood. We have assessed farm management, livestock productivity, and nutrient status of fifteen long term (>10y) certified organic dairy farms in Ontario, Canada. Farm size, herd size and herd productivity averaged 110 ha, 52 cows and 8207 kg milk cow yr-1, respectively. Cropping composition differed little between farms, with pasture and forage accounting for an average of 65% of the cropped landbase. Annual farm nutrient budgets (inputs-outputs) over two years (2003-2005) for N, P and K were 52, 1 and 11 kg ha-1 yr-1, respectively. The majority (13) of farms had positive K budgets with half of the farms recording negative annual P budgets. Nutrient budget results were supported by soil fertility data generated by sampling 80% of farm fields (n=225). Overall, these results contrast strongly with large nutrient surpluses reported for more intensive, confinement-based dairy farms throughout N. America, but suggest a challenge to remain sustainable over the longer term for the 50% of these farms adopting a broadly ‘self-sufficient’ approach, and importing little P (0 - 2.5 kg ha-1 yr-1) as feed and feed supplements