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1.
Composted sewage sludge (biosolids) supply plant available Fe and may represent a sustainable alternative to more costly chelated Fe fertilizers currently used to supplement nutrition in hybrid poplar test plots of elevated soil pH. To test the response of poplars, field plots were amended with composted biosolids at two agricultural rates: 22.75 and 44.5 Mg ha−1. Iron EDDHA served as a fertilizer check and control plots received no amendment. The hybrid poplar OP-367 (Populus deltoides × P. nigra) was planted on a 3.6 m grid spacing. Significant amounts of P and Fe originating from the sewage treatment process were detected in soils 13 months after amending. Chlorosis evaluated with a SPAD-502 meter, showed that poplars amended with biosolids remained the least chlorotic and had greater tree growth when compared to Fe EDDHA and control plots during two growing seasons. Biosolids show promise as a cost effective alternative for the remediation of Fe chlorosis in hybrid poplar agroforestry plantations and present new opportunities in northwestern New Mexico for municipalities seeking solid waste land disposal options.  相似文献   
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We report the attainment of simultaneous quantum degeneracy in a mixed gas of bosons (lithium-7) and fermions (lithium-6). The Fermi gas has been cooled to a temperature of 0.25 times the Fermi temperature by thermal collisions with the evaporatively cooled bosons. At this temperature, the spatial size of the gas is strongly affected by the Fermi pressure resulting from the Pauli exclusion principle and gives clear experimental evidence for quantum degeneracy.  相似文献   
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1. The effect of different light sources (incandescent, sodium vapour, daylight fluorescent and warm fluorescent) and light intensities (10.8 and 86.1 lux) on growth performance and behaviour of female turkeys was investigated in two experiments conducted at different times of the year. 2. Although light source influenced body weight and efficiency of food utilisation, there was no consistent effect between experiments in favour of any particular source. 3. Light intensity had no effect on body weight, efficiency of food utilisation or behaviour.  相似文献   
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An adult great‐horned owl (Bubo virginianus; GHOW) presented with a history of recurrent corneal ulceration of the right eye (OD). Findings included ulcerative superficial keratitis, proliferative conjunctivitis, and iris pigmentary changes. The ulcer was initially nonresponsive to medical therapy, but showed rapid and appropriate healing following diamond burr debridement. Proliferative conjunctivitis markedly improved following topical antiviral therapy with cidofovir 1%, interferon alpha 2B ophthalmic solutions, and oral l ‐lysine. Histopathologic evaluation of a conjunctival biopsy revealed epithelial features suspicious for viral cytopathic changes and intranuclear structures suspicious for viral inclusions, suggestive of a possible viral‐induced papillomatous conjunctivitis. A novel alphaherpesvirus, referred to as Strigid Herpesvirus 1 (StrHV1), was identified using PCR and gene sequencing. This case represents a new clinical manifestation of a previously unreported herpesvirus in the GHOW. Identification of the herpes virus was critical to administration of appropriate therapy and resolution of the conjunctivitis, and corneal epithelial debridement promoted resolution of the chronic corneal epithelial defect.  相似文献   
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Knowledge about normal ranges in semen quality and the association between sperm morphology and fertility in felids is limited. The aims of this retrospective study were to (1) define a normal spermiogram in cats; (2) evaluate possible effects of season, age and breed on sperm morphology; and (3) evaluate the relationship between sperm morphology and fertility. Semen samples collected by electroejaculation from 52 cats were evaluated for sperm morphology. The cats constituted two groups: a general population of cats (n = 48) and cats examined because of poor breeding records (n = 4). The general population was divided into household (n = 20), pedigree (n = 19) and colony cats (n = 9) and into three age classes, <12 months, 12-59 months and >or=60 months. The median percentage of normal spermatozoa in the general population was 44.0% (range 1.0-91.0%). Criteria were tentatively set for what was considered a normal spermiogram. The mean percentage of normal spermatozoa was higher during February to July than during August to January (p < 0.05). Pedigree cats had a lower mean percentage of normal spermatozoa than did household cats (p < 0.05). Age had no effect on the percentage of normal spermatozoa but was positively correlated with the percentage of proximal droplets. Of the cats with <40% normal spermatozoa (n = 19), all those with known breeding records (n = 11) had produced litters. The four cats examined because of poor breeding results had higher percentages of different sperm abnormalities than tentatively stipulated for the normal spermiogram. In two of these cats both sperm morphology and fertility changed over time.  相似文献   
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