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71.
A 6-year-old, intact female, Labrador Retriever/Terrier cross was presented to the University Veterinary Hospital, University College Dublin with a 3-week history of therapy-resistant cervical pain and intermittent fever. Physical examination findings included marked cervical pain resulting in neck extension and vocalization. Examination of the CSF revealed mild pleocytosis (total nucleated cells = 0.009 x 10(9)/L, reference interval <0.005 x 10(9)/L). Cytocentrifuged preparations of the CSF were of low cellularity, containing predominantly macrophages and occasional small lymphocytes. Several small- to medium-sized fragments of a slightly granular, amorphous, eosinophilic substance were observed. The majority of mononuclear cells were located within this material, in small groups of 3-13 cells. The amorphous foamy material stained positive with Luxol fast blue, suggestive of myelin-like material. The dog was euthanized and postmortem examination revealed intervertebral disk protrusion between C2 and C3. Hematoxylin- and Luxol fast blue-stained histopathologic sections of brain and spinal cord revealed only mild hemorrhage. The extracellular material in the CSF of this dog may have been caused by myelin degeneration or leakage of phospholipids from damaged cells. Because no histologic evidence of demyelination was observed with the disk extrusion, the myelin-like material in this case was thought to be the product of phospholipid breakdown from damaged cellular membranes. Three cases of dogs with spinal cord disease and myelin-like material in the CSF have been reported previously. The clinical significance of this finding is still unknown.  相似文献   
72.
The focus of forest-based systems for sequestering carbon has largely been on creating permanent stores of carbon on defined areas of land with a single payment to the forest owner for the carbon. In terms of forest management, this focus leads to two outcomes, continuing production of timber if the forest area is sufficiently large to create an effective permanent carbon pool, or a cessation of harvesting if the forest area is too small. In addition, the payment system for carbon is generally based on matching a specific buyer and seller of carbon using a single payment to the forest owner. In combination, both of these factors create a carbon sequestration system that is too inflexible to attract anything but the largest land or forest owners. The paper presents an alternative system for carbon sequestration, carbon banking. Carbon banking treats sequestered carbon in the same way that a financial institution treats capital. In essence, forest owners ‘deposit’ carbon, in exchange for an annual payment, and those who need carbon offsets ‘borrow’ carbon by making an annual payment. The role of the carbon bank is to aggregate deposits of carbon and use these to meet various demands for carbon. There are a number of benefits of this system. It provides an opportunity for small forest owners with different types, age classes and management strategies to participate in carbon markets because payments are based on current carbon sequestered. It also allows participants in the carbon market to receive current value for carbon rather than what effectively represents the capitalised value of the future benefits of sequestering carbon, thus removing some uncertainty about locking into the wrong value for carbon.  相似文献   
73.
Early food regimes literature tended to concentrate on the global scale analysis of implicitly negative trends in global food relations. In recent years, early food regimes authors like Harriet Friedmann and Philip McMichael have begun to consider the sites of resistance, difference and opportunity that have been emerging around, and into contestation with, new food regime relations. This paper examines the emerging global-scale governance mechanism of environmental food auditing—particularly those being promoted by supermarkets and other large food retailers—as an important new dynamic in our understanding of the politics and potentials of food regimes. Commencing with an examination of Friedmann’s corporate environmental food regime, two key dynamics are identified as being pivotal in the rise and decline of global-scale regimes: securing social legitimacy for food relations and the importance of ecological dynamics in global food relations. By extending McMichael’s notion of ‘Food from Nowhere’ versus ‘Food from Somewhere’, the paper interrogates the emergence of a cluster of relations that comprise ‘Food from Somewhere’ and examines whether this cluster of relations has the potential to change some of the constituent ecological dynamics of food regimes. These ecological dynamics have historically been problematic, amply demonstrating Marx’s metabolic rift as the early food regimes solidified relationships between ‘ecologies at a distance’. By using socio-ecological resilience theory, ‘Food from Somewhere’ is characterized as having denser ecological feedbacks and a more complex information flow in comparison to the invisibility and distanciation characterizing earlier regimes as well as contemporary ‘Food from Nowhere’. The conclusion of this article is that while ‘Food from Somewhere’ does provide one site of opportunity for changing some key food relations and ecologies, the social legitimacy of this new form of food relations does rely on the ongoing existence of the opposite, more regressive, pole of world food relations. The key question for resolving this tension appears to be whether new food relations can open up spaces for future, more ecologically connected, global-scale food relations.  相似文献   
74.
Previous work in the agri-food tradition has framed food auditing as a novelty characteristic of a shift to neoliberal governance in agri-food systems and has tackled the analysis of food “quality” in the same light. This article argues that agri-food scholars’ recent interest in the contested qualities of food needs to be situated alongside a much longer history of contested cultural attributions of trust in food relations. It builds on an earlier discussion suggesting that, although neoliberalism has undoubtedly opened up new spaces for audit activity, older political and social dynamics operating around food audits were established long before the neoliberal historical moment. Breaking new ground (as far as is known) by looking further back than the early history of the organic social movement, it examines intersections of religious food auditing, migrant food culture, and commercial dynamics in food systems. Based on secondary sources, two contrasting case studies are presented to illustrate the flux and complexity for: New World Diaspora migrants to New York City of assuring food was kosher; and more recent Maghrebi migrants to southwest France of assuring food is halal. The article concludes by noting that the neoliberal moment stands not as the unique progenitor of a new style of food authority, but rather as the latest response to a wider rupture in the historically contingent arbitration of new forms of trust in food.  相似文献   
75.
The five‐year value in the compound annual growth rate of the biopesticides sector is predicted to be 16% by 2017 and to produce a global market worth $US 10 billion. Despite this, several impediments occur within the EU that negatively affect biopesticide research and innovation. At present, there are fewer biopesticide‐active substances registered in the EU compared with the United States, India, Brazil and China. The relatively low level of biopesticide research in the EU (6880 ISI papers) versus the United States (18 839), India (9501) and China (7875) relates to the greater complexity of EU‐based biopesticide regulations compared with these other countries. In this light, it is worth noting that tensions may exist between regulators that emphasise the beneficial nature of biopesticides in environmentally friendly crop management and those that adopt a more technologically based approach dependent on a chemical‐pesticide‐driven model. Compared with the other aforementioned countries, far fewer biopesticide products are available in the EU market, mainly as a direct result of the severe regulatory factors present there. The extent to which this trend will continue depends largely on a range of interacting political and/or regulatory decisions that influence environmentally friendly agricultural industries. © 2017 Society of Chemical Industry  相似文献   
76.
77.
Transgenic bromoxynil (BX)-resistant spring oilseed rape (Brassica napus L.) was grown commercially in Canada only for two crop seasons – 2000 and 2001. We investigated the persistence of suspected BX-resistant oilseed rape volunteers in a 64-ha wheat field in Saskatchewan, Canada in 2007, 7 years after the BX-resistant cultivar BX Armor was grown. A small oilseed rape volunteer population, estimated at less than 100 plants, was observed in three main areas or patches in the field. These patches were located in low-lying areas that were too wet to plant or spray with herbicides in 2007. Viable seed was collected from 35 mature volunteers and F1 progeny screened with BX at 280 g ai/ha in the greenhouse. Progeny of all of the volunteers were visually rated as BX-resistant; the presence of the Oxy 235 transgene in leaf tissue of progeny of all volunteers was confirmed by PCR analysis. This study has documented the longest persistence of oilseed rape volunteers in Canada. Volunteers were not observed in 2008 or 2009, because of drought conditions in spring of both years. Results support the findings from previous studies that persistence of volunteer oilseed rape populations in western Canada is generally ephemeral or transitory in the absence of seed bank immigration. However, this study shows that oilseed rape transgenes can persist in the environment for a number of years even after all cultivars with the conferred trait are removed from the market.  相似文献   
78.
Anthrax is a non-contagious disease, known since ancient times. However, it became a matter of global public interest after the bioterrorist attacks in the U.S.A. during the autumn of 2001. The concern of politicians and civil authorities everywhere towards this emergency necessitated a significant research effort and the prevention of new bioterrorist acts. Anthrax is primarily a disease that affects livestock and wildlife; its distribution is worldwide; and it can represent a danger to humans but especially more so when it occurs in areas considered to be free and in atypical seasons and climatic conditions. The atypicality of the phenomenon may lead health workers to misdiagnose and, consequently, an inappropriately manage of affected carcasses with a consequent and inevitable increase in the risk of human infection. This article emphasises the importance of paying increasing attention to this zoonosis. The biggest risk is its underestimation.  相似文献   
79.
80.
Although captive elephants are commonly vaccinated annually against tetanus using commercially available tetanus toxoid vaccines marketed for use in horses and livestock, no data exists to prove that tetanus toxoid vaccination produces measurable antibody titers in elephants. An ELISA test was created to measure antibody responses to tetanus toxoid vaccinations in 22 Asian elephants ranging in age from 24 to 56 years (mean age 39 years) over a 7-month period. All animals had been previously vaccinated with tetanus toxoid vaccine, with the last booster administered 4 years before the start of the study. The great majority of elephants had titers prior to booster vaccination, and following revaccination all elephants demonstrated anamnestic increases in titers, indicating that this species does respond to tetanus vaccination. Surprisingly older animals mounted a significantly higher response to revaccination than did younger animals.  相似文献   
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