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31.
Removing solids from liquid dairy manure slurry reduces manure phosphorus (P) and increases the available (mineral) fraction of nitrogen (N) but also decreases the organic matter content of the manure. While this novel treatment reduces environmental concerns associated with excess N and P application to soils, it may also reduce microbial biomass and activity in soil. This study evaluated the long-term effects of this alternative manure treatment compared to more typical nutrient applications in a perennial grass sward (tall fescue, Festuca arundinacea Schreb.) on soil microbial biomass, community composition, hydrolytic enzyme activity, and forage yield. Nutrient treatments for this long-term field experiment in Agassiz, British Columbia, Canada were started in 2003. The treatments included liquid dairy manure slurry, liquid dairy manure with solids removed, commercial fertilizer, a combination of fertilizer and dairy manure, and a control. All treatments were applied at 400–600 kg total N ha?1 year?1 in four equal doses. Soil microbial community composition (phospholipid fatty acid analysis) and activity (hydrolytic enzyme activity) were determined several times during the 2013 and 2014 growing seasons to a depth of 15 cm. Time of sampling (date) had a strong influence on microbial biomass, community composition, and activity, while the response to soil properties and yield was more varied. All manure treatments (dairy manure slurry, liquid fraction, and the combination) increased microbial biomass (by 19–32%) and the potential activity of cellulose-degrading enzymes (by 31–47%) compared to commercial fertilizer and unamended plots. The commercial fertilizer and liquid fraction lowered fungal/bacterial ratios compared with both whole manure and unamended plots. Our results indicate that separating the solid from the liquid fraction of manure, to improve crop yield and reduce P loading, did not reduce microbial community size and activity and that all manure treatments increased microbial biomass and activity compared to mineral fertilizer application.  相似文献   
32.
Individual organic acids and sugars were analysed in the fruits of scab resistant and susceptible apple cultivars. The total sugars ranged between 128.2 and 191.6 g/kg, and the total organic acid between 5.1 and 13.4 g/kg. In the flesh and peels of different apple varieties single phenolics (gallic, protocatehuic, chlorogenic, caffeic, ferulic and p-coumaric acid, phloridzin, epicatechin, catechin, quercitrin and rutin) were analysed together with their total phenolic content (TPC). ‘Golden Delicious’ was the cultivar with the lowest TPC whereas ‘Rubinola’, ‘Jonagold’ and ‘Goldrush’ had the highest level of TPC in the pulp. Peels showed a 2–9 times higher phenolic content than the pulp. ‘Goldrush’ had the highest content of TPC in its peel. The total antioxidant capacity of peels was about 2–5 times higher than respective pulps. Scab resistant apple cultivars had significantly higher content of some single and total phenolic contents in comparison with the scab susceptible, especially the pulp.  相似文献   
33.
34.
Knowledge of the dimensions of the wetted zone formed under point source surface drip irrigation is essential to the design of cost-effective and efficient irrigation systems. Numerical simulations were carried out with Hydrus-2D/3D to investigate the influence of emitter discharge rates and initial soil moisture conditions on the wetting pattern dimensions of a series of soils with varying textures. Numerical simulations of simple 2D soil tank irrigation experiments were also conducted on two soil types. Based on the simulation results, the parameters of the Schwartzman and Zur model were refined. The results showed a small influence of discharge rates >1 L h?1 on the size of the wetting pattern. The only major difference was observed for the rates lower than 0.5 L h?1, where the largest wetting patterns were observed. Higher initial soil water content caused larger wetting pattern sizes in all directions. When compared to the 2D tank experimental results, Hydrus-2D/3D predicted the wetting pattern dimensions with a relatively small root mean square error not exceeding 2.6 cm. The numerical data obtained for a wide range of textures provided the opportunity to refine the parameters of the Schwartzman and Zur model, which, when compared to experimental data from the literature, provided good estimates of wetting pattern dimensions. This suggests that this simple model, for which the only soil parameter required is the saturated hydraulic conductivity, could provide a valuable and practical tool for irrigation design.  相似文献   
35.
A 2‐month‐old female goat was presented for depressed mental status and multifocal central neurologic signs 3 weeks after hot‐iron disbudding. Conventional magnetic resonance imaging (MRI) findings included a large intra axial mass in the left frontal lobe that was T2 hyperintense and T1 hypointense centrally with a contrast‐enhancing peripheral capsule and perilesional T2 hyperintensity. A restrictive pattern was present in diffusion‐weighted imaging. Magnetic resonance spectroscopy demonstrated an increased amount of succinate, acetate, amino acids, lipids; minimal amounts of lactate; and decreased amounts of N‐acetyl aspartate and choline. A cerebral abscess due to Trueperella pyogenes was confirmed from necropsy and tissue culture.  相似文献   
36.
ObjectiveTo investigate the pharmacokinetics of carprofen after a single intravenous (IV) dose and multiple oral doses administered to pigs undergoing electroporation of the pancreas.Study designProspective experimental study.AnimalsA group of eight female pigs weighing 31.74 ± 2.24 kg (mean ± standard deviation).MethodsCarprofen 4 mg kg?1 was administered IV after placement of a central venous catheter during general anaesthesia with isoflurane. Blood samples were collected 30 seconds before and 5, 10, 20, 30 and 60 minutes and 2, 4, 6, 8, 12 and 24 hours after carprofen administration. Subsequently, the same dose of carprofen was administered orally, daily, for 6 consecutive days and blood collected at 36, 48, 60, 72, 96, 120, 144 and 168 hours after initial carprofen administration. Plasma was analysed using liquid chromatography with mass spectrometry. Standard pharmacokinetic parameters were calculated by compartmental analysis of plasma concentration–time curves. Data are presented as mean ± standard error.ResultsThe initial plasma concentration of IV carprofen was estimated at 54.57 ± 3.92 μg mL?1 and decreased to 8.26 ± 1.07 μg mL?1 24 hours later. The plasma elimination curve showed a bi-exponential decline: a rapid distribution phase with a distribution half-life of 0.21 ± 0.03 hours and a slower elimination phase with an elimination half-life of 17.31 ± 3.78 hours. The calculated pharmacokinetic parameters were as follows: the area under the plasma concentration–time curve was 357.3 ± 16.73 μg mL?1 hour, volume of distribution was 0.28 ± 0.07 L kg?1 and plasma clearance rate was 0.19 ± 0.009 mL minute?1 kg?1. The plasma concentration of carprofen, administered orally from days 2 to 7, varied from 9.03 ± 1.87 to 11.49 ± 2.15 μg mL?1.Conclusions and clinical relevanceCarprofen can be regarded as a long-acting non-steroidal anti-inflammatory drug in pigs.  相似文献   
37.

Background

The prevalence of concurrent disease in hyperthyroid cats is unknown.

Objectives

To identify the prevalence of concurrent intra‐abdominal disease using abdominal ultrasound examination (AUS) in hyperthyroid cats referred for radioactive iodine treatment (RIT) and to determine whether the requirement for pretreatment AUS is justified.

Animals

Five hundred and thirty‐four client‐owned cats diagnosed with hyperthyroidism and referred for RIT.

Methods

Retrospective study. Age, breed, sex, body weight, clinical signs, total serum T4 concentration, blood urea nitrogen (BUN) concentration, serum creatinine concentration, urine specific gravity (USG), AUS results, and biopsy or cytology results, or both (if obtained) were collected from the medical records.

Results

The prevalence of concurrent disease identified using AUS in hyperthyroid cats referred for RIT was 36.1%; 22.8% of the cats in the study had renal disease and 2.4% had confirmed neoplasia. Significant differences in median USG (P value 0.032) and median BUN (P value 0.028) were found between cats that had abnormal kidneys on AUS compared to those with normal‐appearing kidneys. Only 2.2% of the cats were not treated with RIT as a result of changes identified on AUS and subsequently obtained cytology or biopsy results.

Conclusions and Clinical Importance

The results indicate that pretreatment AUS in hyperthyroid cats referred for RIT is unnecessary in most patients.  相似文献   
38.
The effects of crop rotation and fertilization systems on yield and soil fertility parameters have been investigated in a long-term field trial established in southeast Norway in 1953. The results indicate the small differences between crop rotations and different fertilization systems in yield and soil fertility parameters; the decreasing trend in soil organic carbon (SOC) (from 3.8 to 3.7%) and increasing trend of N with time (from 0.32 to 0.36%) and, as a result, the decreasing trend in C/N ratio (from 12 to 10).  相似文献   
39.
After the accident in Fukushima reactors, a daily monitoring programme was initiated in two laboratories in Belgrade, one at the Vin??? Institute for Nuclear Sciences and the other at Institute for Occupational Health Karajovic. Samples of aerosol and fallout, as well as the random samples of food and water, were collected and analysed, using gross alpha/beta and gamma spectrometry, in order to establish the presence of traces of isotopes indicating Fukushima fallout. Gamma spectrometry measurement of these samples showed clear evidence of fission products 131I, 134Cs and 137Cs wtihin 2?weeks after the accident. The activity diminished with time due to dispersion in air and, in case of 131I, short half-life.  相似文献   
40.
This study discusses a novel approach for fabrication of floating photocatalyst which can be efficiently exploited for photodegradation of dyes in aqueous solutions. A fabrication of the floating photocatalyst consisted of two steps: transformation of the poly(ε-caprolactone) beads (PCLb) into poly(ε-caprolactone) foam (PCLf) with porous structure in supercritical carbon-dioxide and subsequent loading of PCLf with TiO2 nanoparticles (NPs). Morphological characterization of the PCLf before and after TiO2 NPs loading was carried out by FESEM. The presence of titanium on the surface and inside the PCLf was detected by EDX. Photocatalytical activity of the floating photocatalyst was investigated in aqueous solution of textile dyes C.I. Acid Orange 7 (AO7) and C.I. Basic Yellow 28 (BY28) which were exposed to lamp that simulates the sun light. In addition to sustainable floatability for a long period of time, developed floating photocatalyst exhibited high rate of photodegradation since the complete discoloration of AO7 and BY28 solutions and photocatalysts alone occurred after 300 and 180 min of illumination, respectively. Its photocatalytic activity was preserved after three repeated photodegradation cycles with unchanged chemical structure that was confirmed by FTIR analysis.  相似文献   
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