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201.
Simon Riguelle Cécile Lesire Jacques Hébert Benoit Jourez 《Wood material science & engineering》2017,12(5):288-294
Timber storage is a key aspect of storm damage management. After huge storms, sprinkling storage is usually the most used conservation process but anaerobic storage in sealed silos appears as good alternative to preserve wood quality over long periods. This paper investigates the impact of long-term (57 months) storage of Norway spruce logs in anaerobic atmosphere on wood properties. Tests were performed on clear wood specimens and on lumbers to determine the modulus of elasticity (E), the static bending strength (σf) and the dynamic bending strength (K). Storage effects on impregnability and colour variation were also studied. Results show no effect of storage on E, σf and K. The naturally poor impregnability of Norway spruce is not improved by the anaerobic conditions, compared to traditional wet storage. Triangle tests reveal no discernible colour variation between logs that underwent anaerobic storage and the control sample. As a conclusion, despite a mould (Gliocladium solani) frequently observed on logs surface after the storage, the process offers ideal conservation conditions. While overall cost remains the main drawback for using anaerobic storage at large scale, the process can be recommended for high value logs, especially since it has few environmental impacts. 相似文献
202.
Chimana Henry M. Muma John Bwalya Samui Kenny L. Hangombe Benard M. Munyeme Musso Matope Gift Phiri Andrew M. Godfroid Jacques Skjerve Eystein Tryland Morten 《Tropical animal health and production》2010,42(7):1541-1545
A cross-sectional study was conducted between January 2007 and February 2008 to estimate seroprevalence of brucellosis and
identify risk factors associated with Brucella infections in commercial cattle in three districts of Lusaka province (Chongwe, Luangwa, and Kafue; n = 849) and in one rural district from the Central province (n = 48). A total of 897 serum samples were randomly collected from 55 farms along with animal-level data such as sex, age,
and parity. Sera were screened for presence of anti-Brucella antibodies using the Rose Bengal test, and positive samples were confirmed using competitive enzyme-linked immunosorbent
assay. At the animal level, seroprevalence was estimated at 7.9% (95% CI = 4.4–11.4%) in the Lusaka province and 18.7% (95%
CI = 7.5–29.9%) for Chibombo district. Brucellosis seroprevalence varied according to district, with Chongwe district recording
the highest compared to other districts. Seroprevalence also varied according to sex with bulls (n = 96) having higher seroprevalence (12.5%; 95% CI = 3.8–21.1%) compared to females (8.1%; 95% CI = 4.6–11.6). Similarly,
seroprevalence varied according to age groups, with the age category 1–4 years recording the highest (10.7%). The study recorded
relatively low Brucella seroprevalence in commercial farms in Lusaka, compared to the traditional small-scale farms. We suggest that testing and
stamping out of infected animals is likely to improve the situation and significantly reduce the public health risk associated
with Brucella infections in animals. 相似文献
203.
Nicolas Desneux Eric Wajnberg Kris A. G. Wyckhuys Giovanni Burgio Salvatore Arpaia Consuelo A. Narváez-Vasquez Joel González-Cabrera Diana Catalán Ruescas Elisabeth Tabone Jacques Frandon Jeannine Pizzol Christine Poncet Tomás Cabello Alberto Urbaneja 《Journal of pest science》2010,83(3):197-215
The tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a devastating pest of tomato originating from South America. After its initial detection in eastern Spain in 2006, it rapidly invaded various other European countries and spread throughout the Mediterranean basin. If no control measures are taken, then the pest can cause up to 80–100% yield losses in tomato crops in recently invaded areas and may pose a threat to both greenhouse and open-field tomato production. The exceptional speed and extent of T. absoluta invasion have called for studies documenting its biology and ecology, while indicating an urgent need for efficient and sustainable management methods. The development of approaches to manage T. absoluta would be facilitated through a detailed revision of information on this pest in its area of origin. This review combines information on the invasion by T. absoluta, its ecology, and potential management strategies, including data that may help the implementation of efficient biological control programs. These programs, together with a variety of other management tactics, may allow efficient integrated pest management of T. absoluta in Europe and Mediterranean Basin countries. 相似文献
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Lucius Tamm Barbara Thürig Christian Bruns Jacques G. Fuchs Ulrich Köpke Matias Laustela Carlo Leifert Nicole Mahlberg Bruno Nietlispach Christoph Schmidt Felix Weber Andreas Fließbach 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(4):465-481
The impact of soil type, long-term soil management, and short-term fertility input strategies on the suppressiveness of soils against soil-borne (Ocimum basilicum – Rhizoctonia solani, Lepidium sativum – Pythium ultimum) as well as air-borne (Lycopersicon esculentum – Phytophthora infestans, Arabidopsis thaliana – Hyaloperonospora parasitica) diseases was studied. Soils from field trials established in five European sites with contrasting pedo-climatic conditions were examined. Sites included (i) a long-term management field trial comparing organic and conventional farming systems (DOK-trial, Therwil, Switzerland) (ii) a short-term fertility input field trial comparing mineral and organic matter fertilisation regimes (Bonn (BON), Germany) (iii) two short-term fertility input field trials (Stockbridge (STC) and Tadcaster (TAD), UK) comparing the impact of farmyard manure, composted farmyard manure, and chicken manure pellet amendements and (iv) soil from a site used as a reference (Reckenholz (REC), Switzerland). Soil type affected disease suppressiveness of the four pathosystems signficantly, indicating that soils can not only affect the development of soil-borne, but also the resistance of plants to air-borne diseases at relevant levels. Suppressiveness to soil- and air-borne diseases was shown to be affected by soil type, but also by long-term management as well as short-term fertility inputs. 相似文献
207.
Palcy C Silvestre A Sauve C Cortet J Cabaret J 《Veterinary journal (London, England : 1997)》2010,183(1):68-74
This is the first report of benzimidazole (BZ) resistance in the nematode Trichostrongylus axei in sheep. Trichostrongylus axei infects several species of herbivores including sheep, cattle and horses, and the emergence of anthelmintic resistance could lead to significant problems in its control. Benzimidazole resistance in two sheep flocks in central France was detected by post-treatment worm counts. The sequencing of a central region of the isotype 1 beta-tubulin gene from adult T. axei recovered post-mortem revealed only one, non-synonymous single nucleotide polymorphism at position 200 (Phe200Tyr), which had already been reported for other nematodes. Seven years after BZ treatment ceased, T. axei helminths present were still resistant to BZ suggesting these parasites do not revert to susceptibility to this anthelmintic, even when the selection pressure had been removed for many years. The findings also highlight major changes in the make-up of the nematode burden in sheep flocks that accompanies the emergence of BZ resistance. 相似文献
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Jacques M Aragon V Tremblay YD 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2010,11(2):97-121
Bacterial biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that is attached to a surface. Biofilms protect and allow bacteria to survive and thrive in hostile environments. Bacteria within biofilms can withstand host immune responses, and are much less susceptible to antibiotics and disinfectants when compared with their planktonic counterparts. The ability to form biofilms is now considered a universal attribute of micro-organisms. Diseases associated with biofilms require novel methods for their prevention, diagnosis and treatment; this is largely due to the properties of biofilms. Surprisingly, biofilm formation by bacterial pathogens of veterinary importance has received relatively little attention. Here, we review the current knowledge of bacterial biofilms as well as studies performed on animal pathogens. 相似文献