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BACKGROUND: Although worker representation in OHS has been widely recognized as contributing to health and safety improvements at work, few studies have examined the role that worker representatives play in this process. Using a large quantitative sample, this paper seeks to confirm findings from an earlier exploratory qualitative study that worker representatives can be differentiated by the knowledge intensive tactics and strategies that they use to achieve changes in their workplace. METHODS: Just under 900 worker health and safety representatives in Ontario completed surveys which asked them to report on the amount of time they devoted to different types of representation activities (i.e., technical activities such as inspections and report writing vs. political activities such as mobilizing workers to build support), the kinds of conditions or hazards they tried to address through their representation (e.g., housekeeping vs. modifications in ventilation systems), and their reported success in making positive improvements. A cluster analysis was used to determine whether the worker representatives could be distinguished in terms of the relative time devoted to different activities and the clusters were then compared with reference to types of intervention efforts and outcomes. RESULTS: The cluster analysis identified three distinct groupings of representatives with significant differences in reported types of interventions and in their level of reported impact. Two of the clusters were consistent with the findings in the exploratory study, identified as knowledge activism for greater emphasis on knowledge based political activity and technical-legal representation for greater emphasis on formalized technical oriented procedures and legal regulations. Knowledge activists were more likely to take on challenging interventions and they reported more impact across the full range of interventions. CONCLUSIONS: This paper provides further support for the concepts of knowledge activism and technical-legal representation when differentiating the strategic orientations and impact of worker health and safety representatives, with important implications for education, political support and recruitment. Am. J. Ind. Med. © 2015 Wiley Periodicals, Inc. Language: en

Since their inception in the early 1960s, constant price national accounts have contained a measurement inconsistency in the expenditure accounts which flows through to the production accounts. The inconsistency has the effect of excluding changes in the terms of trade (the ratio of export prices to import prices) from real gross domestic product, so that it is unequal to real gross domestic income, which includes them. In economies, such as those of Australia and Canada, that experience substantial changes in the terms of trade, a real gross domestic product excluding those effects becomes a misleading guide for macroeconomic analysis and policy.

Cet article etudie l'introduction, en 1987, d'une politique sur les mesures de controle des conflits de travail a Windsor, en Ontario. La politique met l'accent sur l'usage explicite du consensus en fondant ses strategies sur la coercition en situation de greve. Les evene-ments qui ont menea la mise en place de cette politique sont lies aux politiques regionales sur les mesures de controle ainsi qu'aux conditions economiques et industrielles en changement representant le declin general des relations industrielles fondees sur le modele de Ford. Des changements a l'interieur des forces policieres tels que la mise sur pied de la police communautaire sont aussi consideres comme des explications importantes. La politique sur les conflits de travail ainsi que les changements dans les corps policiers sont consideres comme le reflet du declin de l'Etat keynesien et du mouvement vers le neoliberalisme. This paper examines the 1987 introduction of a policy for policing labour disputes in Windsor, Ontario. The policy emphasizes the explicit use of consensus-building tactics over coercion in strike situations. Events leading to this policy are traced to the local politics of policing and to changing economic and industrial conditions representing the general decline in Fordist industrial relations. Changes within the police, such as the adoption of community policing, are also considered as important explanations. Both the labour-dispute policy and the broader police changes are understood as reflecting the decline of the Keynesian state and the movement toward neoliberalism.

L'auteur examine dans cet article l'elaboration d'un discours sur l'agriculture, qui encourage l'adoption d'un travail de conservation du sol comme agriculture ecologiquement durable. L'analyse debute par l'argument selon lequel ce discours est ne dans les annees 1980, en reponse aux consequences sur l'environnement de l'agriculture classique. On soutient ensuite que l'attention portee au travail du sol plutot qu'a d'autres solutions de rechange quant a ces impacts, attention qui doit etre comprise dans le cadre d'une analyse plus large des developpements politico-economiques dans le domaine de l'agriculture au Canada. On a determine que les interests contradic-toires des divers secteurs de l'industrie agroalimentaire, en ce qui concerne le maintien de l'utilisation de produits chimiques couteux et le controle des prix payes aux agriculteurs dans le contexte de la crise economique de l'agriculture, jouaient un role essentiel dans l'attention portee au travail du sol. On soutient que le travail de conservation du sol permet de regler ces contradictions de deux facons. Tout d'abord, le travail de conservation du sol a fourni une base pour affirmer que les problemes de pollution chimique et d'epuisement du sol etaient en train d'etre resolus sans que soient necessaires des changements plus substantiels dans le systeme de production a base chimique. Enfin, il offrait aux agriculteurs un moyen et une raison de reduire les couts de production devant les crises constantes relatives aux prix et a la rentabilite des fermes. This paper examines the development of a discourse within agriculture which promotes the adoption of conservation tillage as environmentally sustainable farming. The analysis begins with the argument that the discourse emerged during the 1980s as a response to the environmental impacts of conventional agriculture. It is then argued that the focus on tillage practices over other alternative solutions to these impacts must be understood within a broader analysis of the political-economic developments in Canadian agriculture. The contradictory interests of the various sectors of agribusiness capital, both in sustaining the use of expensive chemical inputs and in controlling the prices paid to farmers within the context of the farm economic crisis, are identified as playing a vital role in shaping the focus on tillage practices. It is contended that conservation tillage offered a means of mediating these contradictions in two ways. First, conservation tillage provided a basis for the claim that chemical pollution and soil depletion problems were being resolved without the need for more substantial changes in the chemically-based production system and, second, it gave farmers a means and a rationale for cutting production costs in the face of continuing crises in prices and profitability at the farm gate level.

This article examines the health and safety perceptions and practices of conventional, no till and organic grain farmers in Ontario Canada. Based on 12 intensive case studies, the analysis examines whether different restructuring and environmental orientations are related to different approaches to occupational health and safety. The analysis suggests that although there is a substantial level of awareness and knowledge of health and safety hazards among all the farmers, significant differences in practices are linked in complex and somewhat unexpected ways to the production and environmental approaches of the farmers. In particular, while economic constraints and rationales provide an overriding basis for risk-taking across all the farmers, the level and form that this takes is shaped by farmer orientations to farm management and the environment. The article also links both the common patterns and variations in farmer practices to corporate and government discourses on the prevention of environmental and occupational injuries, suggesting that mixed messages undermine any effort to intensify farmer commitment to safety.

This paper seeks to explain variations in gender participation in farm production and decision-making through an analysis of organic farm types, sizes, and orientations. Based on both survey and case study data, the analysis shows that female farmers on vegetable farms and mixed livestock/cash crop farms are more likely to be involved in farm production and management than women on field crop farms, where mechanization and capital intensive production is much higher. The links to ideological orientations and motivations are also examined, suggesting that farmers with more conventional orientations to organic farming are also less likely to support gender equality.

Shigella proteins that are targeted to host cells by a type III secretion apparatus are essential for reorganization of the cytoskeleton during cell invasion. We have developed a semi-permeabilized cell assay that tests the effects of bacterial proteins on the actin cytoskeleton. The Shigella IpaC protein was found to induce the formation of filopodial and lamellipodial extensions in these semi-permeabilized cells. Microinjection of IpaC into cells, or cellular expression of IpaC also led to the formation of filopodial structures. Monoclonal antibodies (mAbs) directed against the C-terminus of IpaC inhibited the IpaC-induced extensions, whereas an anti-N-terminal IpaC mAb stimulated extensive lamellae formation. Shigella induced foci of actin polymerization in the permeabilized cells and these were inhibited by anti-C-terminal IpaC mAbs. Consistent with a role for IpaC in Shigella-induced cytoskeletal rearrangements during entry, stable transfectants expressing IpaC challenged with Shigella showed increased bacterial internalization. IpaC-induced extensions were inhibited by a dominant-interfering form of Cdc42 or the Cdc42-binding domain of WASP, whereas a dominant-interfering form of Rac resulted in inhibition of lamellae formation. We conclude that IpaC leads to activation of Cdc42 which in turn, causes activation of Rac, both GTPases being required for Shigella entry.

Astrocytes are typically star shaped cells playing diverse roles in the function of the nervous system. In astrocyte cultures established from the cerebral hemispheres of newborn rats, the cells have generally a polygonal fibroblast-like morphology, but acquire a stellate shape upon serum removal. When the serine protease thrombin or the bioactive lipid lysophosphatidic acid is added, the stellate cells revert to the flat morphology. Here we show that the effect of these agents is mediated via activation of the small GTP-binding protein Rho. Neither thrombin nor lysophosphatidic acid induced spreading of astrocytes microinjected with C3 transferase, an exoenzyme which ADP-ribosylates and thereby inactivates Rho. In contrast, the response of cells injected with a dominant negative form of Rac was unaffected. In addition, the injection of active Rho into stellate astrocytes mimicked the effect of thrombin and lysophosphatidic acid and an injection of C3 into flat cells grown in serum induced stellation. The conversion from a stellate to a spread morphology upon activation of Rho resulted in the formation of stress fibers and focal adhesions which most probably are key events in establishing and stabilizing the altered cytoarchitecture. These results suggest that Rho plays a crucial role in determining the shape of astrocytes and thereby may modulate their interaction with neurons in vivo.

AlF4− has long been known to associate with and activate the GDP-bound alpha subunits of heterotrimeric G-proteins. Recently the small guanine nucleotide binding protein Ras has also been shown to associate with AlF4− in the presence of stoichiometric amounts of its G TPase a ctivating p rotein (GAP). Here we present the isolation of a stable Ras·GDP·AlF4−·GAP ternary complex by gel filtration. In addition, we generalise the association of AlF4− with the small GTP-binding proteins by demonstrating ternary complex formation for the Cdc42, Rap and Ran proteins in the presence of their respective GAP proteins.

Lysophosphatidic acid (LPA) and bombesin rapidly stimulate the formation of focal adhesions and actin stress fibres in serum-starved Swiss 3T3 fibroblasts, a process regulated by the small GTP binding protein Rho. To investigate further the signalling pathways leading to these responses, we have tested the roles of three intracellular signals known to be induced by LPA: activation of protein kinase C (PK-C), Ca2+ mobilization and decreased cAMP levels. Neither PK-C activation nor increased [Ca2+]i, alone or in combination, induced stress fibre formation, and in fact activators of PK-C inhibited this response to LPA and bombesin. The G(i)-mediated decrease in cAMP was not required for the response to LPA, and increased cAMP levels did not prevent stress fibre formation. In contrast, the tyrosine kinase inhibitor genistein inhibited the formation of stress fibres induced by both extracellular factors and microinjected Rho protein. Genistein also inhibited the Rho-dependent clustering of phosphotyrosine-containing proteins at focal adhesions, and the increased tyrosine phosphorylation of several proteins including pp125FAK, induced by LPA and bombesin. This suggests a model where Rho-induced activation of a tyrosine kinase is required for the formation of stress fibres.

RhoGDI inhibits guanine nucleotide dissociation from post-translationally processed Rho and Rac proteins but its biochemical role in vivo is unknown. We show here that N-terminal effector site mutations in the Rac protein do not compromise its interaction with RhoGDI and that, whilst geranylgeranylation and -AAX proteolysis of the C-terminal CAAX motif of Rac1 and RhoA are required for efficient interaction with RhoGDI, methylesterification of the C-terminal cysteine residue is not required. In vitro, RhoGDI can form stable complexes with Rho and Rac proteins in both the GTP and GDP bound states. Furthermore the Rac-GTP--RhoGDI complex is resistent to the action of recombinant RhoGAP and recombinant BCR. Thus GDI, by complexing with Rac-GTP and preventing GAP stimulated GTP hydrolysis, may allow transit of the activated form of the Rac protein between physically separated activator and effector proteins in the cell.

Rho, a member of the Ras superfamily of small GTPases, has multiple biological roles: it regulates signal trasduction pathways linking extracellular growth factors to the assembly of actin stress fibres and focal adhesion complexes; it is required for G1 progression and activates the SRF transcription factor when quiescent fibroblasts are stimulated to grow; and it plays a role later in the cell cycle during cytokinesis. Two groups have recently succeeded in identifying downstream effectors of Rho that may mediate some of these biological effects. One protein identified by both groups is protein kinase N (PKN), a serine/threonine kinase whose catalytic domain is closely related to that of protein kinase C(1,2).

Increasing concerns have been expressed about whether the alternative character of the organic farming movement is being maintained as it grows in size and popularity. This paper examines this question with respect to organic farming in Ontario, Canada. Using survey and case study data, a number of production, marketing, ideology, and farm size characteristics are assessed as indicators of overall conventionalization as well as the bifurcation of organic farming into two distinct groups. While signs of conventionalization and bifurcation are demonstrated, particularly in the area of field crop farming, the overall analysis suggests that most organic farms retain the central features of an alternative approach, including an emphasis on small, diverse, mixed operations, marketing directly and locally to consumers

It has previously been demonstrated that efficient DNA synthesis by oncogenic p21H-ras only occurs in the presence of insulin and is absolutely dependent on functional protein kinase C. Here we show that morphological transformation induced by oncogenic p21H-ras does not require functional protein kinase C. The early phases of protein kinase C-independent morphological transformation do not require de novo protein synthesis. We have also demonstrated that the introduction of p21H-ras into quiescent Swiss 3T3 cells by scrape-loading leads to increased levels of c-myc mRNA similar to those seen following serum stimulation. The increases in c-myc mRNA levels induced by p21H-ras are also independent of functional protein kinase C. Both morphological transformation and the elevation of c-myc mRNA levels do not require insulin. These results demonstrate that p21H-ras is generating protein kinase C-dependent and -independent signals.

Experiments using the physical loading of purified recombinant p21 ras proteins into quiescent normal cells to analyze how the proteins stimulate DNA synthesis and morphological transformation are reviewed. The results indicate that oncogenic p21 ras proteins rapidly activate a protein-kinase-C-dependent pathway and a protein-kinase-C-independent pathway. The activation of protein kinase C is absolutely required for p21 ras to stimulate DNA synthesis but is not required for morphological transformation