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321.
Thiamine is an essential dietary nutrient in cats; however, studies on the stability of thiamine in pet food are limited. The objective of this study was to analyze thiamine concentrations in commercial feline extruded diets over time at room and freezing temperatures. Twelve diets were split in half and thiamine concentrations were assessed using fluorometry. One half of each diet was then stored at room temperature (24°C) and the other half was frozen (−20°C). Subsamples were analyzed at 2 other time points at 6-month intervals up to 1 year. Data were assessed using a mixed procedure (2-factor factorial model with factors time and treatment). Based on F-tests, thiamine concentrations decreased over time (P = 0.001), with no treatment*time interaction (P = 0.9534). In conclusion, regardless of treatment, thiamine degraded at a similar rate over time.  相似文献   
322.
Belchip, a round white, widely adapted potato variety, especially useful for chips, was released by the U.S. Department of Agriculture, the Agricultural Experiment Stations of Florida, New Jersey, and Maine, and the Virginia Truck and Ornamental Research Station, Norfolk in 1978. Belchip is immune to viruses A and X and tuber net necrosis caused by the leaf roll virus; highly resistant to race O of late blight and tuber necrosis caused by high soil temperatures; and has not shown unusual susceptibility to other major potato diseases. Maturity is about 5 days later than Atlantic. Tubers of Belchip are flat round in shape with shallow eyes. Tubers may be irregular in conformation under nitrogen deficiency and water stress. Total solids content ranges from 18 percent in Florida to 23 percent in Maine. Chips made from Belchip were lighter in color than those processed from varieties currently grown along the Atlantic Seaboard. Belchip reconditions readily in 2–3 weeks from 4°C (39°F) storage.  相似文献   
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Cereal crops accumulate low levels of iron (Fe) of which only a small fraction (5–10%) is bioavailable in human diets. Extensive co-localization of Fe in outer grain tissues with phytic acid, a strong chelator of metal ions, results in the formation of insoluble complexes that cannot be digested by humans. Here we describe the use of synchrotron X-ray fluorescence microscopy (XFM) and high resolution secondary ion mass spectrometry (NanoSIMS) to map the distribution of Fe, zinc (Zn), phosphorus (P) and other elements in the aleurone and subaleurone layers of mature grain from wild-type and an Fe-enriched line of rice (Oryza sativa L.). The results obtained from both XFM and NanoSIMS indicated that most Fe was co-localized with P (indicative of phytic acid) in the aleurone layer but that a small amount of Fe, often present as “hotspots”, extended further into the subaleurone and outer endosperm in a pattern that was not co-localized with P. We hypothesize that Fe in subaleurone and outer endosperm layers of rice grain could be bound to low molecular weight chelators such as nicotianamine and/or deoxymugineic acid.  相似文献   
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The use of land for intensive arable production in Europe is associated with a range of externalities that typically impose costs on third parties. The introduction of trees in arable systems can potentially be used to reduce these costs. This paper assesses the profitability and environmental externalities of a silvoarable agroforestry system, and compares this with the profitability and environmental externalities from an arable system and a forestry system. A silvoarable experimental plot of poplar trees planted in 1992 in Bedfordshire, Eastern England, was used as a case study. The Yield-SAFE model was used to simulate the growth and yields of the silvoarable, arable, and forestry land uses along with the associated environmental externalities, including carbon sequestration, greenhouse gas emissions, nitrogen and phosphorus surplus, and soil erosion losses by water. The Farm-SAFE model was then used to quantify the monetary value of these effects. The study assesses both the financial profitability from a farmer perspective and the economic benefit from a societal perspective. The arable option was the most financially profitable system followed by the silvoarable system and forestry. However, when the environmental externalities were included, silvoarable agroforestry provided the greatest benefit. This suggests that the appropriate integration of trees in arable land can provide greater well-being benefits to society overall, than arable farming without trees, or forestry systems on their own.  相似文献   
327.
Recent evidence suggests a possible association of Felis catus papillomavirus type 2 (FcaPV-2) DNA with feline oral squamous cell carcinoma (FOSCC). In this study, type-specific PCR targeting two genes (L1/E6 or E1/E6) of FcaPV-1/-2/-3/-4/-5/-6 was performed to detect viral DNA in a large amount of FOSCC samples collected in Italy and Austria. FcaPV-1/-2/-3/-4/-5 were detected in 7/113 (6.2%), 7/93 (7.5%), 6/113 (5.3%), 1/113 (0.9%) and 2/113 (1.8%) specimens, respectively, with different prevalences in Italian vs. Austrian samples, whilst FcaPV-6 went undetected. Our results confirms that FcaPV-2 is the most prevalent in FOSCC, followed by FcaPV-1/-3 and suggest that FcaPVs have variable circulation rates in European countries.  相似文献   
328.
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