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1.
The objective of this study was to evaluate the response of healthy housebound domestic cats to the simultaneous provision of 2 litterboxes of differing sizes by recording the average daily frequency of urination and defecation in each box. Forty-three households with 74 privately owned cats were each provided with 2 different-sized plastic containers, with the larger box being 86 cm in length, exceeding the size of commercially available litterboxes. Owners were also provided with an unlimited supply of clumping cat litter and a logbook to record daily urine and fecal deposits in the boxes as they were scooped over a 4-week period. The 2 litterboxes were initially placed at opposite sides of the same room in the owner's home. After 2 weeks, the boxes were emptied completely, refilled with clean clumping litter, and replaced in the opposite location. Results were recorded as simple counts of urine and fecal deposits for each day and each household. Over the 28-day period, there were a total of 5031 urine and fecal deposits in the larger boxes and 3239 urine and fecal deposits in the regular boxes. The effects of phase (days 1-14 vs. 15-28) and box size (regular vs. large) on the number of deposits per cat were evaluated using a linear mixed model. In addition to evaluating phase and box size, the effects of number of cats in the house, their average age, and gender were also evaluated. Urine deposits were significantly more frequent than fecal deposits. Large boxes were preferentially selected over regular boxes in both phases, but this difference was greater in phase 1 than phase 2. Further analysis indicated that there was a location preference during the first 2 days in phase 2, and this effect decreased as the study progressed. Results indicate that most cats show a definite preference for a larger litterbox than is typically available to them in homes and that other factors such as box cleanliness and location may have a compounding influence on this choice. 相似文献
2.
草地地上生物量(Aboveground biomass,AGB)是衡量草地生产力的关键因素,准确测定草地AGB具有重要意义。高光谱因具有时效性强、不破坏草地等特点被广泛用于草地生理生态指标的测定。本研究提取和计算了海北试验站高寒草地冠层的原始光谱(Original spectrum,OR)反射率、一阶微分光谱(First derivative spectrum,FD)反射率、光谱位置面积参数(Spectral parameters of spectral position and area,PA)和植被指数(Vegetation indices,VI)4种不同类型的特征变量,使用连续投影算法(Successive projections algorithm,SPA)和递归特征消除算法(Recursive feature elimination,RFE)进行特征选择,采用随机森林算法(Random forest,RF)构建草地AGB估测模型。结果表明:在由4种特征变量分别构建的草地AGB估测模型中,基于VI的RF模型精度最高(测试集R2=0.70,RMSE=557.87 kg·ha-1),实测AGB与估测AGB的线性R2达到0.72;不同类型特征变量组合构建的草地AGB估测模型中,PA+VI组合的RF模型精度最高(R2=0.71,RMSE=548.97 kg·ha-1),实测AGB和估测AGB的线性R2达到0.73。 相似文献
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Chen Siqing Chen Tinghuai Zhou Liuding 《保鲜与加工》1992,(4):21-25
The rank one updating formula and the parallel eliminating algorithm for linear recurrence systems ane combined fo form a MTMD parallel algorithm fo solve tridiagonal Toeplitz Cinear equations. This algorithm has a simple strictire and requires onlty a few storages as well as in-terprocessor communications. There is no special demand on the number of processors in the parallel system. The speedup can come dose to p12 comparing with the LU decomposition method (p is the number of processors). It is worth pointing out that it is proposed algcmthn that considels and organizes the parallel arithmetic in the first order linear ricurrence systems with constant coefficients. 相似文献
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Sabnis S 《Veterinary research communications》1999,23(7):425-447
The oral route is presently the preferred route of drug delivery. Poor oral bioavailability results in variable concentrations of drugs in the plasma and variable pharmacological responses, in addition to higher product costs. The unique canine physiology, anatomy and biochemistry makes designing canine dosage forms a challenging exercise. This article reviews the physicochemical, physiological, pharmacokinetic, pharmacological and formulation factors that can influence the drug availability of the oral formulations in dogs in an effort to provide a source of data to aid development of canine drug products with superior bioavailability. 相似文献
6.
武威地区天然草地有毒植物及其防除 总被引:12,自引:2,他引:10
对武威地区天然草地有毒植物的种类,分布及其对草地的危害情况进行了调查研究,结果表明,全区天然草地共有毒植物172号,分属31科84属,平均2.15种/m^2,盖度达4.41%地上部分生物量11.28g/m^2。对草地危害的主要黄花棘豆,甘肃棘豆,小花棘豆,狼毒和马草,受侵害的草地主要是山地草甸和山地草原,通过分析,提出了有毒植物防除和利用的建议。 相似文献
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Laddawan Krongpong Kunihiko Futami Takayuki Katagiri Makoto Endo Masashi Maita 《Fisheries Science》2008,74(5):1055-1061
Furazolidone, an antibacterial drug that was once widely used in the livestock industry and aquaculture, is now prohibited
in numerous countries. It is difficult to detect residual furazolidone because it is readily metabolized in animal tissues
but, by using and liquid chromatography coupled with tandem mass spectrometry, its metabolite, 3-amino-2-oxazolidinone (AOZ)
can be detected. Here we describe the validity of an enzyme-linked immunosorbent assay (ELISA) kit to detect AOZ in Japanese
eel Anguilla japonica tissue. ELISA is capable of detecting AOZ at 1.0 μg/kg in an eel sample with excellent accuracy and precision. Our results
show that ELISA is suitable for regulatory purposes and for studying the fate of AOZ residues in eel treated with furazolidone.
To measure the persistence of AOZ in eel tissues, eels (1.4–6.5g) were immersed in tanks containing 2 and 10 mg furazolidone/L
for 3 h, and then maintained in a tank supplying well water for the next 160 days. The half-lives of AOZ, calculated from
the linear terminal part of the excretion curve, were 25.0 days in muscle and 21.6 days in liver from fish exposed to 2 mg/L
furazolidone. In the eels treated with 10 mg/L furazolidone, by contrast, high levels of AOZ were detected in liver and muscle,
but the half-lives of AOZ were similar to those in fish treated with 2 mg/L furazolidone. The half-lives of AOZ in eel tissues
were prolonged by the condition of low water temperature. 相似文献
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