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111.
David Maxwell Suckling Lloyd D Stringer Joshua E Corn Barry Bunn Ashraf M El‐Sayed Robert K Vander Meer 《Pest management science》2012,68(12):1572-1578
BACKGROUND: The fire ant, Solenopsis invicta, is one of the most aggressive and invasive species in the world. The trail pheromone Z,E‐α‐farnesene (91% purity) was prepared, and disruption of worker trail orientation was tested using an ethanol‐based aerosol formulation presenting a single puff of this compound by airbrush and compressed air. Trail‐following behaviour was recorded by overhead webcam and ants digitised before and after presentation of the aerosol treatment at four rates (1.6, 16, 160 and 1600 ng cm?2). RESULTS: Ants preferred 110 ng cm?1 over 11, 1.1 and 0.11 ng cm?1 for trail following. Within seconds of presentation of 1600 ng cm?2, the highest dose tested, trail disruption was observed. Disruption was evident as reduced arrival success and reduction in the trail integrity statistic (r2), as well as increased deviation from the trail (deg). The distribution of walking track angles was also flattened. CONCLUSIONS: The feasibility of using aerosol for delivery of trail pheromone was demonstrated, but the need for high purity combined with the difficulty of commercial supply makes this technique impractical. However, the commercial production of Z,E‐α‐farnesene of high purity by industrial biotechnology or from (E)‐nerolidol may be possible in future, which would facilitate further development of trail pheromone disruption of S. invicta. Copyright © 2012 Society of Chemical Industry 相似文献
112.
Sonnenberg GF Monticelli LA Alenghat T Fung TC Hutnick NA Kunisawa J Shibata N Grunberg S Sinha R Zahm AM Tardif MR Sathaliyawala T Kubota M Farber DL Collman RG Shaked A Fouser LA Weiner DB Tessier PA Friedman JR Kiyono H Bushman FD Chang KM Artis D 《Science (New York, N.Y.)》2012,336(6086):1321-1325
The mammalian intestinal tract is colonized by trillions of beneficial commensal bacteria that are anatomically restricted to specific niches. However, the mechanisms that regulate anatomical containment remain unclear. Here, we show that interleukin-22 (IL-22)-producing innate lymphoid cells (ILCs) are present in intestinal tissues of healthy mammals. Depletion of ILCs resulted in peripheral dissemination of commensal bacteria and systemic inflammation, which was prevented by administration of IL-22. Disseminating bacteria were identified as Alcaligenes species originating from host lymphoid tissues. Alcaligenes was sufficient to promote systemic inflammation after ILC depletion in mice, and Alcaligenes-specific systemic immune responses were associated with Crohn's disease and progressive hepatitis C virus infection in patients. Collectively, these data indicate that ILCs regulate selective containment of lymphoid-resident bacteria to prevent systemic inflammation associated with chronic diseases. 相似文献
113.
Joshua Sbicca 《Agriculture and Human Values》2012,29(4):455-466
The food justice movement is a budding social movement premised on ideologies that critique the structural oppression responsible for many injustices throughout the agrifood system. Tensions often arise however when a radical ideology in various versions from multiple previous movements is woven into mobilization efforts by organizations seeking to build the activist base needed to transform the agrifood system. I provide a detailed case study of the People’s Grocery, a food justice organization in West Oakland, California, to show how anti-oppression ideology provides the foundation upon which food justice activists mobilize. People’s Grocery builds off of previous social justice movements within West Oakland, reflected in activist meaning making around ideas of social justice and autonomy. However, the ongoing mobilization process also faces complications stemming from diverse individual interpretations of food justice—that may not be reflected in the stated goals of food justice organizations—as well as structural constraints. Consequently, building a social movement premised on food justice opens up social spaces for new activism, but may not be a panacea for solving food-related racial and economic inequality. The findings have implications for newly forming food justice organizations, future research on the food justice movement, as well as for theories on social movement mobilization. 相似文献
114.
115.
Human-wildlife conflict (HWC) is a conservation concern that increasingly threatens the continued existence of some of the world's most endangered species. With an increase in human population, urban sprawl and subsequent encroachment on wild land, human and wildlife interaction has become inevitable. In the majority of cases, this interaction results in a negative outcome for humans, wildlife or both. In China, these key elements, along with a decrease in wild prey species, have resulted in the expansion of HWC encounters, and the need for alleviating this conflict has become a conservation priority. Loss of human life, livestock and/or crops is most often the catalysts that fuel HWC. Techniques to alleviate conflict around the world have included preventative measures and mitigation techniques, such as financial compensation and other incentive programs. Both types of measures have had variable success. We review the current status of human-carnivore conflict management in China, and, drawing lessons from around the globe, we make recommendations for improving conservation management in China. For example, an increase in law enforcement in nature reserves is vital to reducing human disturbance in prime carnivore habitat, thereby reducing conflict encounters. Also, modifications to current wildlife compensation programs, so that they are linked with preventative measures, will ensure that moral hazards are avoided. Furthermore, investigating the potential for a community self-financed insurance scheme to fund compensation and increasing efforts to restore wild prey populations will improve the outcome for wildlife conservation. Ultimately, HWC management in China will greatly benefit from an integrative approach. 相似文献
116.
Joshua A. Stern Jeremy R. Tobias Bruce W. Keene 《Journal of Veterinary Cardiology》2012,14(4):537-539
Third degree atrioventricular (AV) block was observed in a patient with a roughly spherical mass measuring approximately 1 × 1 × 1 cm, visible in the basilar portion of the interventricular septum on 2-dimensional transthoracic echocardiographic examination. The patient had a brief history of lethargy and episodic collapse, and the owner elected to euthanize the dog after the mass lesion was discovered. Necropsy revealed multiple masses within the interventricular septum, ventricular free walls and atrial myocardium. The final diagnosis was large cell (T-cell) lymphosarcoma. 相似文献
117.
David O. EHIZIBOLO Joshua KAMANI Peter O. EHIZIBOLO Kinsley O. EGWU Goni I. DOGO Josiah O. SALAMI-SHINABA 《Journal of Equine Science》2012,23(1):1-4
This study was conducted to determine the prevalence and significance of parasites of
horses in northern Nigeria. Blood and faecal samples were randomly collected from 243
horses from different stables in some states of northern Nigeria for laboratory analyses.
Fifty-seven horses (23.5%) were found infected with parasites. The hemoparasites detected,
21 (8.6%), include Theileria equi, Babesia caballi, Trypanosoma vivax and Trypanosoma
evansi. The endoparasites encountered, 29 (11.9%) were Strongylus spp., Strongyloides
spp., Oxyuris equi, Parascaris equorum, Paragonimus spp. and Dicrocoelium spp., 3 (1.2%)
was Eimeria spp. Four horses (1.6%) had mixed infection of hemo- and endoparasites. This
preliminary finding shows that parasitism is a problem in the horse stables examined, and
calls for proper stable hygiene, routine tick control and regular deworming programme. 相似文献
118.
Amanda Sherman Joshua B. Daniels David A. Wilkie Elizabeth Lutz 《Veterinary ophthalmology》2013,16(5):386-391
A 5‐year‐old spayed female diabetic mixed‐breed dog underwent phacoemulsification and intraocular lens implantation to correct bilateral hypermature cataracts. Two months postsurgery, the patient presented with ulcerative keratitis and multifocal stromal abscessation OD, which was controlled, but never resolved, with topical fluoroquinolone therapy. The patient re‐presented 2 months later with a new, raised, white gritty corneal opacity associated with hyperemia, chemosis, and blepharospasm OD. Cytology of the right cornea revealed filamentous bacteria, suggestive of Actinomyces spp. Actinomyces bowdenii was subsequently isolated in pure culture and identified via 16s rDNA sequencing. Actinomyces bowdenii has never before been described as a cause of ocular infection. An immunosuppressed corneal environment likely contributed to this opportunistic Actinomycosis. The infection was not controlled with fluoroquinolone therapy, and the isolate, in vitro, was resistant to three fluoroquinolones (ciprofloxacin, ofloxacin, and levofloxacin), which also has not been previously reported for this species of Actinomyces. A superficial keratectomy with conjunctival graft was employed to successfully manage the infection. 相似文献
119.
王晶晶 《国外畜牧学(猪与禽)》2013,33(4):37-39
仔猪断奶后腹泻在猪场的发生率很高,这使养猪生产者遭受了严重的经济损失。有机酸可导致胃内pH值下降,不利于致病菌生存。但由于致病菌的固有抵抗力,含有大量游离有机酸的混合物,与植物化学物质和渗透性物质(Biotronic Top3)的联合使用可以更有效地提高动物的生产性能和控制致病菌。 相似文献
120.
Farm and Village Forest Use Practice in Ekiti State: Analysis of Government Policy and Tenure Issues
Joshua Kayode 《Journal of Sustainable Forestry》2013,32(4):321-328
This study analyzed the influence of government policy and tenure issues on farm and village forest use practices in Ekiti State, Nigeria. Three rural communities that were still far from urban influence were selected from each of the 16 local government areas of the state. In each community, 20 household heads were selected and interviewed with the aid of a semi-structured matrix. The interviews aimed at the determination of respondents' socioeconomic status, awareness and belief in the effectiveness or otherwise of the forest laws and regulations, land use, tenure and property rights. Results obtained revealed that the awareness of forest laws and regulations cut across the socio-economic categories. Most of these laws and regulations that were considered to be necessary could also constitute disincentives to sustainable forest development. Three types of land tenure niches—private holdings, commons, and government reserves—exist in the state. These led to land fragmentations in which individuals are now left with small holdings. Individuals with small and medium landholdings found it difficult to invest in tree planting; hence, they meet their subsistence use of wood and non-wood forest products from diverse sources. Individuals with large landholdings were found cultivating cash tree crops; timber species were not cultivated though their wildlings were preserved. Also, when land is let or leased out, tenants were not allowed to invest in tree planting on such land. 相似文献