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191.
192.
Insa S Besalú E Iglesias C Salvadó V Anticó E 《Journal of agricultural and food chemistry》2006,54(3):627-632
The appearance of 2,4,6-trichloroanisole (TCA) in cork stoppers is of great concern because it can cause off-flavors in bottled wine. To prevent this sensorial defect, there should not be any traces of 2,4,6-trichlorophenol (TCP), 2,3,4,6-tetrachlorophenol (TeCP), or pentachlorophenol (PCP) in the finished corks, because they are the direct precursors of TCA. In the course of this study two methodologies based upon an extraction with ethanol/water mixtures to determine the chlorophenolic content in cork matrices were developed. The cork extract is preconcentrated using both solid-phase extraction and solid-phase microextraction methodologies. The latter was optimized by applying a full two-level factorial design. Finally, spiked ground corks at nanogram per gram levels of each chlorophenol were analyzed under optimal conditions and by applying both procedures. The obtained results demonstrate that chlorophenols can be detected in corks contaminated at the nanogram per gram level and, thus, these approaches can be successfully applied as quality control measures in the cork industry. 相似文献
193.
Salal (Gaultheria shallon) is a vigorous evergreen perennial shrub that is native to the west coast of North America, where it can reduce overstorey growth rates and negatively impact regeneration. Since its introduction into the UK almost a century ago it has become an increasing problem in many woodlands, where it completely shades out other understorey vegetation including young trees, preventing forest regeneration. Climate change is likely to favour its future spread in the UK, and in other regions which currently have a similar climate such as Ireland and northwest Europe. Non chemical management is only practical on a small scale, and to date efforts to control this invasive weed with herbicides have been largely ineffective. In our work we found that a single application of 2.69 kg active ingredient (a.i.) ha?1 picloram [as 11.2 l ha?1 Tordon 22 K (240 g l?1 picloram)] diluted in water plus the adjuvant Mixture B NF at 2% of final spray volume, applied between spring and midsummer, killed all treated plants within two growing seasons. Treatment with 3.84 kg a.i. ha?1 triclopyr [as 8 l ha?1 Timbrel (480 g l?1 triclopyr)] diluted in water plus Mixture B NF at 2% of final spray volume, sprayed initially when flower buds are swelling or flushed but vegetative buds are largely dormant (late April in southern Britain), with a repeat application made 4–8 weeks later, was also very effective. If triclopyr or picloram cannot be used, we also found that glyphosate can provide some control, but follow up treatment will be required. In addition, silvicultural practices such as the high density planting of heavily shade bearing species should be adopted to discourage subsequent reinfestation of cleared areas. 相似文献
194.
María Antonia Gómez-Martínez Josep A. Jaques María Victoria Ibáñez-Gual Tatiana Pina 《Journal of pest science》2018,91(2):613-623
Biological control of Tetranychus urticae Koch (Acari: Tetranychidae), a key pest of clementines, can be improved in this crop with the establishment of a ground cover of Festuca arundinacea Schreber (Poaceae). This cover houses an abundant and diverse community of predatory Phytoseiidae mites including Euseius stipulatus (Athias-Henriot), Neoseiulus barkeri Hughes, Neoseiulus californicus (McGregor) and Phytoseiulus persimilis Athias-Henriot and a dense population of the grass thrips Anaphothrips obscurus Müller (Thysanoptera: Thripidae) throughout the year. The aim of this study was to determine whether the presence of this thrips species could be related to the improvement in the biological control of T. urticae. Therefore, the capacity of the abovementioned phytoseiids to feed and reproduce on A. obscurus and their feeding preferences when T. urticae and A. obscurus were simultaneously offered, were analyzed. The results show that E. stipulatus, N. barkeri and N. californicus have a type II functional response when offered A. obscurus nymphs, whereas P. persimilis barely feeds on this thrips species. Furthermore, N. barkeri and N. californicus can reproduce feeding only on thrips. Regarding prey preference, the Tetranychus spp.-specialist P. persimilis preferably preyed on T. urticae, the generalists N. barkeri and E. stipulatus preferred A. obscurus, and the selective predator of tetranychid mites N. californicus showed no preference. Therefore, we hypothesize that the enhanced biological control of T. urticae observed could be related to A. obscurus becoming an alternative prey for non-specialist phytoseiids, without altering the control exerted by the T. urticae-specialist P. persimilis and likely reducing intraguild predation. 相似文献
195.
Retrospective evaluation of cats with elapid snake envenomation associated neurotoxicity requiring mechanical ventilation: 12 cases (2005–2014) 下载免费PDF全文
196.
Investigating the impact of innate dexterity skills and visuospatial aptitude on the performance of baseline laparoscopic skills in veterinary students 下载免费PDF全文
197.
Christiane von der Ohe Victoria Gauthier Lily Tamburic-Ilincic Anita Brule-Babel W. G. Dilantha Fernando Randy Clear Todd J. Ward Thomas Miedaner 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(3):407-417
Twenty four isolates of Fusarium graminearum, half of which were 3-acetyldeoxynivalenol (3-ADON) and half 15-acetyldeoxynivalenol (15-ADON) chemotypes, were tested for
their ability to produce deoxynivalenol and to cause Fusarium head blight (FHB) in spring wheat cultivars. The objectives
of this study were to determine (1) whether 3-ADON isolates differ in aggressiveness, as measured by the FHB index, and DON
production from 15-ADON isolates under field conditions, and (2) whether the performance of resistant host cultivars was stable
across isolates. Field tests of all isolates were conducted with three replicates at each of two locations in Canada and Germany
in 2008 with three host genotypes differing in FHB resistance level. The resistant host genotype showed resistance regardless
of the chemotype or location. The differences between mean FHB indices of 3-ADON and 15-ADON isolates were not significant
for any wheat genotype. In contrast, average DON production by the 3-ADON isolates (10.44 mg kg−1) was significantly (P < 0.05) higher than for the 15-ADON isolates (6.95 mg kg−1) at three of the four locations where moderately resistant lines were tested, and at both locations where susceptible lines
were evaluated. These results indicate that 3-ADON isolates could pose a greater risk to food safety. However, as the mean
aggressiveness and DON production of 3-ADON and 15-ADON chemotypes was similar on highly resistant lines, breeding and use
of highly resistant lines is still the most effective measure of reducing the risks associated with DON in wheat. 相似文献
198.
Katherine A Damcevski Greg Dojchinov James D Woodman Victoria S Haritos 《Pest management science》2010,66(4):432-438
BACKGROUND: The ethyl formate/carbon dioxide (CO2) formulation Vapormate? is a rapid‐acting fumigant being developed for the control of stored‐grain insects. The effects have been investigated of concentration, exposure times of 1, 3, 24 and 72 h and two grain temperatures, 15 and 25 °C, on its efficacy against mixed‐stage cultures of Sitophilus oryzae (L.) Tribolium castaneum (Herbst) and strongly phosphine‐resistant Rhyzopertha dominica (F.) strain QRD569. RESULTS: High mortalities (≥92%) of mixed‐stage cultures of all three species were obtained when grain was fumigated with the formulation (193 g m?3 ethyl formate) for 1 h. Complete control of R. dominica QRD569 and T. castaneum was achieved with 63 and 76 g m?3 ethyl formate respectively, with exposure for 24 h, whereas mean mortality of S. oryzae was 86% under the same conditions. Mortalities of S. oryzae juvenile stages were significantly lower than adults under the conditions tested, which was due to pronounced tolerance of mid‐stage pupae to the fumigant. Reducing grain temperature from 25 to 15 °C had no effect on insect mortality. CONCLUSION: Ethyl formate/CO2 formulation is highly effective against stored‐grain insects over a range of concentrations and exposure times. Efficacious fumigations were conducted in as little as 1 h, and a strongly phosphine‐resistant R. dominica strain was readily controlled with the fumigant. Copyright © 2009 CSIRO, Australia. Published by John Wiley & Sons, Ltd 相似文献
199.
José de la Fuente Katherine M. Kocan Edmour F. Blouin Zorica Zivkovic Victoria Naranjo Consuelo Almazán Eliane Esteves Frans Jongejan Sirlei Daffre Atilio J. Mangold 《Veterinary parasitology》2010,167(2-4):175-186
The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several tick-transmitted pathogens that impact veterinary and human health. Tick-borne pathogens cycle between tick vectors and vertebrate hosts and their interaction is mediated by molecular mechanisms at the tick–pathogen interface. These mechanisms have evolved characteristics that involve traits from both the tick vector and the pathogen to insure their mutual survival. Herein, we review the information obtained from functional genomics and genetic studies to characterize the tick–Anaplasma interface and evolution of A. marginale and A. phagocytophilum. Anaplasma and tick genes and proteins involved in tick–pathogen interactions were characterized. The results of these studies demonstrated that common and Anaplasma species-specific molecular mechanism occur by which pathogen and tick cell gene expression mediates or limits Anaplasma developmental cycle and trafficking through ticks. These results have advanced our understanding of the biology of tick–Anaplasma interactions and have opened new avenues for the development of improved methods for the control of tick infestations and the transmission of tick-borne pathogens. 相似文献
200.
Elsa Beltran Alberta De Stefani Jennifer Stewart Luisa De Risio Victoria Johnson 《Veterinary ophthalmology》2010,13(3):184-189
Mast cell tumors are found in most organs and tissues with variable biologic behavior in dogs. This case illustrates the clinical and magnetic resonance imaging (MRI) findings in a dog with disseminated mast cell tumor infiltrating the sphenoid bones. A 6‐year‐old male neutered Greyhound presented with a 3‐day history of acute onset of blindness. General physical examination was normal. Neurological examination revealed mildly disorientated mental status, absent menace response in both eyes, bilaterally decreased vestibulo–oculocephalic reflexes and absent direct and consensual pupillary light reflex in both eyes. An electroretinogram indicated normal retinal function in both eyes. A lesion involving the middle and rostral cranial fossa was suspected. Hematology and serum biochemistry were normal except decreased urea (1.2 mmol/L). MRI of the head revealed heterogeneous signal intensity of the sphenoid bones on T2‐weighted images and loss of their normal internal architecture. Cerebrospinal fluid analysis was normal. Abdominal ultrasound revealed hepatosplenomegaly and mesenteric lymphadenopathy. Fine needle aspirates were taken from the jejunal lymph nodes and the spleen. Results were consistent with disseminated mast cell tumor. The owner declined any treatment and the dog was euthanatized. Postmortem examination confirmed disseminated mast cell tumor affecting multiple organs, including the sphenoid bones. To our knowledge, this is the first case describing MRI features of disseminated mast cell tumor affecting the sphenoid bones and causing acute onset of blindness in a dog. 相似文献