the effect of phosphate on the transformation of ferrihydrite into crystalline products in alkaline media     

Paige  C. R.  Snodgrass  W. J.  Nicholson  Ronald V.  Scharer  J. M.  He  Q. H. 《Water, air, and soil pollution》1997,97(3-4):397-412

The presence of phosphate retards the transformation of ferrihydrite into crystalline products. Increasing phosphate from 0 to 1 mole % results in an order of magnitude decrease in the rate of transformation of ferrihydrite at pH 12. Levels of phosphate of ～1 mol % suppress the formation of goethite (α-FeO(OH)) and result in the formation of a product consisting ofη-Fe₂O₃. Higher levels of phosphate result in the ferrihydrite remaining amorphous, even after several hundred hours. Phosphate prevents formation of goethite by hindering the dissolution of ferrihydrite rather than by interfering with nucleation and growth of goethite in solution. The transformation rate of pure ferrihydrite is also strongly inhibited in the presence of dissolved phosphate. This is due to surface complexation. The transformation rate was measured at temperatures of 60 °C and 70 °C. The rate of transformation was found to be described by either (i) a solid-state reaction equation for powdered compacts or (ii) a zero-order reaction controlled by desorption. The transformation of the ferrihydrite matrix was accompanied by the loss of the phosphate trace component. X-ray diffraction indicates that no solid solution involving phosphate substitution intoη-Fe₂O₃ is formed. Transmission electron microphotographs of the original precipitates containing phosphate confirm the presence of the phosphate and demonstrate its involvement in linking together extremely small particles of ferrihydrite.  相似文献   

Mucopolysaccharidosis type VII in a German Shepherd Dog     

Silverstein Dombrowski DC  Carmichael KP  Wang P  O'Malley TM  Haskins ME  Giger U 《Journal of the American Veterinary Medical Association》2004,224(4):553-7, 532-3

A 12-week-old male German Shepherd Dog was evaluated because of a 3-week history of a progressive inability to ambulate. Clinical and laboratory findings included skeletal deformities, corneal cloudiness, cytoplasmic granules in the neutrophils and lymphocytes of blood and CSF and glycosaminoglycans in a urine sample (detected via a toluidine blue spot test). Enzyme activity and DNA analyses confirmed mucopolysaccharidosis type VII as a result of severe beta-glucuronidase deficiency; this condition had been identified in a mixed-breed dog (likely of German Shepherd Dog descent) that was reported 20 years earlier and caused by the same missense mutation. Because of the progressive nature of this disease, the puppy was euthanatized and all tissues examined contained evidence of lysosomal storage leading to marked cellular distention. Mucopolysaccharidosis type VII is only one of many hereditary lysosomal storage diseases identified in companion animals. It is important that clinicians recognize the typical signs of lysosomal storage diseases and are aware of the cytologic and urinary screening tests for mucopolysaccharidosis disorders. Furthermore, there are specific blood enzyme and DNA-based tests to distinguish the forms of mucopolysaccharidosis in affected and carrier animals.  相似文献   

Molecular basis of globoid cell leukodystrophy in Irish setters     

McGraw RA  Carmichael KP 《Veterinary journal (London, England : 1997)》2006,171(2):370-372

Globoid cell leukodystrophy (GLD), or Krabbe's disease, is a progressive autosomal recessive disorder of the central nervous system in man and in various other species. GLD has been shown to result from various mutations in the gene encoding galactocerebrosidase (GALC), a lysosomal enzyme. We investigated the molecular basis of GLD in a related group of Irish setters. Sequencing of the GALC cDNA from an affected individual revealed an insertion mutation of 78 base pairs (bp) consisting of 16 bp of insertion site duplication and 62 bp of sequence derived from the U4 small nuclear RNA. We implemented a PCR-based test which is useful for identifying carriers of the mutation.  相似文献   

Debilitation and mortality associated with besnoitiosis in four Virginia opossums (Didelphis virginiana)     

Ellis AE  Mackey E  Moore PA  Divers SJ  Hensel P  Carmichael KP  Accola P  Brown J  Gottdenker N  Keel MK  Shock BC  Yabsley MJ 《Journal of zoo and wildlife medicine》2012,43(2):367-374

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Ocular lesions following suspected lightning injury in a horse     

Evans PM  Armour MD  Dubielzig RR 《Veterinary ophthalmology》2012,15(4):276-279

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Ecology and management of earthworm casting on sports turf     

Paige E Boyle  Michael D Richardson  Mary C Savin  Douglas E Karcher  Daniel A Potter 《Pest management science》2019,75(8):2071-2078

Earthworm activity is beneficial in most natural and agricultural systems, but excessive earthworm casting is a problem on sports fields worldwide. Expulsion of soil‐rich earthworm fecal matter, or casts, as mounds of soil on the turf canopy can muddy the surface, reduce photosynthesis, and lead to thinning, weed invasion and surface softening. Casts affect ball roll on sports fields, cause fouling of maintenance equipment, and dull mower blades. Build‐up of cast material on reel mower units can affect height and quality of cut. Casting activity is dependent on environmental conditions such as soil texture, temperature, moisture, pH, and organic matter. Response to environmental conditions varies by species. Management options are limited, because no pesticides are specifically labeled for earthworm control at this time, and cultural control methods such as soil modification, turfgrass clipping removal, and sand topdressing have limited and inconsistent efficacy. Products containing plant‐derived saponins and irritants show promise for earthworm management. Pest management practices to mitigate excessive earthworm casting will likely need to be species‐specific, but limited knowledge of earthworm identification by end‐users further inhibits the efficacy of control measures. © 2019 Society of Chemical Industry  相似文献   

Ovicidal lectins from Moringa oleifera and Myracrodruon urundeuva cause alterations in chorionic surface and penetrate the embryos of Aedes aegypti eggs     

Robson RV Alves  Tatiana Soares  Elinaldo FL Bento  Ricardo S Roldan‐Filho  Brbara SS Souza  Marcele KN Lima  Jssica S Nascimento  Luana CBB Coelho  Roberto A S  Thmarah A Lima  Gabriel GA Gonalves  Fbio A Brayner  Luiz C Alves  Daniela MAF Navarro  Thiago H Napoleo  Patrícia MG Paiva 《Pest management science》2020,76(2):730-736

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What is your diagnosis? Peritoneal fluid from an Arabian horse after colic surgery     

Pratt SM  Christian JA  Paige Jackson L  Hawkins JF  Sojka JE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(2):253-255

A 16-year-old castrated male Arabian horse was presented to the Purdue University Veterinary Teaching Hospital with a 4-hour history of colic. Initial examinations provided strong evidence for small intestinal obstruction. Abdominal surgery revealed a strangulating lipoma, and 25 feet of small intestine were resected. Postoperatively, the horse developed obstructive ileus due to adhesion formation, which required a second laparotomy. During and after surgery, the abdomen was lavaged with sodium carboxymethylcellulose (CMC). One week after the second surgery, evaluation of peritoneal fluid revealed an inflammatory exudate, with many macrophages containing amorphous to granular, pink to magenta phagocytosed material. Extracellular aggregates of the material were also observed. The material was consistent with CMC. To our knowledge, this report is the first to demonstrate the phagocytosis of CMC by peritoneal fluid macrophages.  相似文献   

Oxalate‐degrading bacteria,including Oxalobacter formigenes,colonise the gastrointestinal tract of healthy koalas (Phascolarctos cinereus) and those with oxalate nephrosis     

KN Speight  M Houston‐Francis  M Mohammadi‐Dehcheshmeh  E Ebrahimie  S Saputra  DJ Trott 《Australian veterinary journal》2019,97(5):166-170

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Tracking the long-term decline and recovery of an isolated population     

RL Westemeier  JD Brawn  SA Simpson  TL Esker  RW Jansen  JW Walk  EL Kershner  JL Bouzat  KN Paige 《Science (New York, N.Y.)》1998,282(5394):1695-1698

Effects of small population size and reduced genetic variation on the viability of wild animal populations remain controversial. During a 35-year study of a remnant population of greater prairie chickens, population size decreased from 2000 individuals in 1962 to fewer than 50 by 1994. Concurrently, both fitness, as measured by fertility and hatching rates of eggs, and genetic diversity declined significantly. Conservation measures initiated in 1992 with translocations of birds from large, genetically diverse populations restored egg viability. Thus, sufficient genetic resources appear to be critical for maintaining populations of greater prairie chickens.  相似文献