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1.
Morrow RC Tibbitts TW 《HortScience : a publication of the American Society for Horticultural Science》1987,22(1):148-151
A system was developed for subjecting plants to elevated air ion levels. This system consisted of a rectangular Plexiglas chamber lined with a Faraday cage. Air ions were generated by corona discharge from frayed stainless steel fibers placed at one end of the chamber. This source was capable of producing varying levels of either positive or negative air ions. During plant exposures, environmental conditions were controlled by operating the unit in a growth chamber. 相似文献
2.
Deanna L. Funnell Christopher B. Lawrence Jeffrey F. Pedersen Christopher L. Schardl 《Physiological and Molecular Plant Pathology》2004,65(6):285-296
Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR. 相似文献
3.
Carla M K Morrow Victor E Valli Petra A Volmer Paul A Eubig 《Journal of veterinary diagnostic investigation》2005,17(3):223-231
Ten dogs suffered acute renal failure after ingesting > or = 3 g/kg (dry matter) of grapes or raisins. All dogs had degeneration or necrosis (or both) of proximal renal tubules with basement membranes remaining intact, and epithelial regeneration was observed in 5 out of 10 cases. Mineralized tubular debris or granular to proteinaceous casts (or both) were present in all cases. A golden-brown, globular, intracellular pigment of varying amounts and sizes was observed in 6 out of 10 cases with variable reaction with Prussian blue. Multifocal fibrinous arteritis of the large colon was seen in 2 out of 5 cases with globulin insudation of vessel wall demonstrated by immunohistochemical staining for immunoglobulin (Ig)G and IgM. Mineral analysis on frozen renal tissue from 2 out of 2 cases revealed mildly elevated Ca:P ratio in both. Clinically significant observations were preservation of the integrity of basement membranes after grape-induced tubular injury and presence of early epithelial regeneration. Thus, recovery may be possible if anuria is aggressively managed. With respect to potential pathophysiologic mechanisms, further research into the roles of calcium homeostasis, vascular reactivity, and the significance of the golden-brown pigment is indicated. 相似文献
4.
Cheri Nielsen Deanna A Sutton Ilze Matise Nicole Kirchhof Melissa C Libal 《Journal of veterinary diagnostic investigation》2005,17(4):372-378
Cokeromyces recurvatus, a zygomycete, was isolated by fungal culture from the peritoneal fluid of a cat with jejunal perforation secondary to intestinal lymphosarcoma. This organism has not been recovered previously from a veterinary patient. The tissue form of C. recurvatus is morphologically similar to those of Coccidioides immitis and Paracoccidioides brasiliensis and may be misdiagnosed as 1 of these organisms on the basis of cytologic or histopathologic specimens, particularly in geographic regions where these organisms are not endemic. 相似文献
5.
Acute selenite toxicosis in lambs 总被引:3,自引:0,他引:3
D A Morrow 《Journal of the American Veterinary Medical Association》1968,152(11):1625-1629
6.
T.M. Brown-Brandl J.A. Nienaber R.A. Eigenberg T.L. Mader J.L. Morrow J.W. Dailey 《Livestock Science》2006,105(1-3):19-26
Heat stress in cattle causes decreases in feed intake and feed efficiency; in extreme cases, it can cause death. These losses amount to millions of dollars each year. A study was designed to determine severity of heat stress among four breeds of cattle. Throughout two summers, 256 feedlot heifers of four different breeds were observed. Respiration rates, panting scores, and surface temperatures were taken twice each day on 10 animals/breed for several weeks during the summers of 2002 and 2003. Twenty-four-hour behavior measurements were recorded for four heat-stress and four thermoneutral days. Results showed during the afternoon, Angus cattle (black) had the highest respiration rates, panting scores, and surface temperatures, followed by the MARC III (dark red), Gelbvieh (tan), and Charolais (white). Behavior data showed that heat stress increased drinking and standing behavior, and decreased eating, lying, and agonistic behaviors, and that dark-hided cattle adjusted their behavior more than light-hided cattle. Overall, it was found that breed of cattle with dark-hides were more affected by temperature changes and at peak temperatures than breeds of cattle with light-hides. 相似文献
7.
Deanna H. Olson Paul D. Anderson Christopher A. Frissell Hartwell H. Welsh Jr. David F. Bradford 《Forest Ecology and Management》2007
Stream–riparian areas represent a nexus of biodiversity, with disproportionate numbers of species tied to and interacting within this key habitat. New research in Pacific Northwest headwater forests, especially the characterization of microclimates and amphibian distributions, is expanding our perspective of riparian zones, and suggests the need for alternative designs to manage stream–riparian zones and their adjacent uplands. High biodiversity in riparian areas can be attributed to cool moist conditions, high productivity and complex habitat. All 47 northwestern amphibian species have stream–riparian associations, with a third being obligate forms to general stream–riparian areas, and a quarter with life histories reliant on headwater landscapes in particular. Recent recognition that stream-breeding amphibians can disperse hundreds of meters into uplands implies that connectivity among neighboring drainages may be important to their population structures and dynamics. Microclimate studies substantiate a “stream effect” of cool moist conditions permeating upslope into warmer, drier forests. We review forest management approaches relative to headwater riparian areas in the U.S. Pacific Northwest, and we propose scenarios designed to retain all habitats used by amphibians with complex life histories. These include a mix of riparian and upslope management approaches to address the breeding, foraging, overwintering, and dispersal functions of these animals. We speculate that the stream microclimate effect can partly counterbalance edge effects imposed by upslope forest disturbances, hence appropriately sized and managed riparian buffers can protect suitable microclimates at streams and within riparian forests. We propose one approach that focuses habitat conservation in headwater areas – where present management allows extensive logging – on sensitive target species, such as tailed frogs and torrent salamanders that often occur patchily. Assuming both high patchiness and some concordance among the distribution of sensitive species, protecting areas with higher abundances of these animals could justify less protection of currently unoccupied or low-density habitats, where more intensive forest management for timber production could occur. Also, we outline an approach that protects juxtaposed headwater patches, retaining connectivity among sub-drainages using a 6th-field watershed spatial scale for assuring well-distributed protected areas across forested landscapes. However, research is needed to test this approach and to determine whether it is sufficient to buffer downstream water quality and habitat from impacts of headwater management. Offering too-sparse protection everywhere is likely insufficient to conserve headwater habitats and biodiversity, while our alternative targeted protection of selected headwaters does not bind the entire forest landscape into a biodiversity reserve. 相似文献
8.
Deanna R. Worley 《Veterinary and comparative oncology》2015,13(2):152-153
9.
10.
Juan Valencia Chris Harwood Russell Washusen Andrew Morrow Matthew Wood Peter Volker 《Wood Science and Technology》2011,45(1):15-34
Peripheral longitudinal growth strain (LGS) was measured on a total of 81, 22-year-old pruned Eucalyptus nitens trees from five thinning treatments in a plantation thinning trial in Tasmania. Growth strain data were gathered at breast
height on each tree using the CIRAD-Forêt method. The effects of thinning treatment and tree diameter on LGS and its relationships
to solid-wood traits determined in a processing trial were examined. LGS was significantly higher in the direction of the
prevailing wind and was not significantly affected by either thinning treatment or tree diameter. An index of log end splitting
was positively related to tree diameter, sawlog position (upper/lower), and LGS, which explained up to an additional 20% of
the variance after tree diameter and log position were accounted for in a linear regression model. High LGS and log end splitting
were significant indicators of increased board end splitting. 相似文献