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为揭示不同基因型烤烟的光合特性,通过大田试验,利用LI-6400XT光合测定系统测定了毕节烟区4种主栽品种上部叶片的光、CO2的响应曲线,分别利用Farquhar模型和直角双曲线模型拟合光、CO2曲线,阐述了4个品种光响应和CO2响应特征及其主要参数.结果表明,4个品种响应曲线规律基本一致,响应特征参数差异明显.云烟97对高光照的适应能力相对最强、碳同化能力也表现较好;K326则表现出对弱光和低摩尔分数CO2的利用效率,对环境适应能力较强;毕纳1号饱和CO2速率明显高于其余品种,具有一定的高产潜力;红花大金元的优势体现在自身碳同化过程中的羧化效率.高海拔区域,选择种植云烟97能发挥其适应高光照的优势;中低海拔区域,K326和毕纳1号适应性较好,且能更好地发挥其生产潜力. 相似文献
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The existence of a dominant massive planet, Jupiter, in our solar system, although perhaps essential for long-term dynamical stability and the development of life, may not be typical of planetary systems that form around other stars. In a system containing two Jupiter-like planets, the possibility exists that a dynamical instability will develop. Computer simulations suggest that in many cases this instability leads to the ejection of one planet while the other is left in a smaller, eccentric orbit. In extreme cases, the eccentric orbit has a small enough periastron distance that it may circularize at an orbital period as short as a few days through tidal dissipation. This may explain the recently detected Jupiter-mass planets in very tight circular orbits and wider eccentric orbits around nearby stars. 相似文献
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以花粉育性和小穗育性为指标 ,对红莲型细胞质雄性不育系丛广 4 1 A、恢复系特青以及丛广 4 1 A/特青的 F1 、F2 ,丛广 4 1 A∥丛广 4 1 B/特青的三交 F1 等亲本和杂种群体的育性调查分析结果表明 :特青具有 1个主效的显性恢复基因 ,该基因暂命名为 Rf-5(t) ;对红莲型细胞质雄性不育系丛广 4 1 A、恢复系珍汕 97以及丛广 4 1 A/珍汕 97的 F1 、F2 ,丛广 4 1 A∥丛广 4 1 B/珍汕 97的三交 F1 等亲本和杂种群体的育性调查分析结果表明 :在红莲型细胞质雄性不育和恢复性上 ,这 2个亲本之间可能有两类基因 ,其中一类控制着圆败型花粉 ,另一类控制着典败型花粉 ;对丛广 4 1 A∥珍汕 97/特青三交 F1 的育性调查分析结果表明 :珍汕 97具有一个与 Rf-5(t)等位的恢复基因 相似文献
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Objective To evaluate organoleptic postmortem inspection techniques for bovine livers and kidneys.
Study design At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement.
Results A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1df, P = 0.002) and kappa 0.35.
Conclusions The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns. 相似文献
Study design At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement.
Results A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1df, P = 0.002) and kappa 0.35.
Conclusions The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns. 相似文献
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LINDA VAN HOOGMOED DVM Diplomate ACVS JACK R. SNYDER DVM PHD Diplomate ACVS GREGORY ROBERTS DVM MS Diplomate ACVR FA YE A. HARMON 《Veterinary surgery : VS》1997,26(6):497-501
Objective —The purpose of this study was to decribe the clinical presentation, diagnostic evaluation, and surgical management of a llama with an ectopic ureter.
Animals or Sample Population —Nine-month-old female llama.
Results —The diagnostic evaluation included the use of computed tomography and an excretory ureterogram to confirm and identify the location of the ectopic ureter. Surgical management involved a unilateral nephrectomy.
Conclusions and Clinical Relevance —Computed tomography is a valuable asset to diagnose the presence and terminal location of an ectopic ureter in llamas, and nephrectomy appears to be a viable procedure to resolve the subsequent urinary incontinence. 相似文献
Animals or Sample Population —Nine-month-old female llama.
Results —The diagnostic evaluation included the use of computed tomography and an excretory ureterogram to confirm and identify the location of the ectopic ureter. Surgical management involved a unilateral nephrectomy.
Conclusions and Clinical Relevance —Computed tomography is a valuable asset to diagnose the presence and terminal location of an ectopic ureter in llamas, and nephrectomy appears to be a viable procedure to resolve the subsequent urinary incontinence. 相似文献
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Paige M. Schmidt Robert A. McCleery Roel R. Lopez Nova J. Silvy Jason A. Schmidt Neil D. Perry 《Landscape Ecology》2011,26(10):1419-1431
Degradation of coastal systems has led to increased impacts from hurricanes and storm surges and is of concern for coastal
endemics species. Understanding the influence of disturbance on coastal populations like the endangered Lower Keys marsh rabbit
(Sylvilagus palustris hefneri) is important to understanding long-term dynamics and for recovery planning. We evaluated the effect of disturbance on the
rabbits by determining which patch, habitat, and landscape characteristics influenced habitat use following Hurricane Wilma.
We determined patch-level occurrence 6–9 months prior to Hurricane Wilma, within 6 months following the hurricane, and 2 years
after the storm to quantify rates of patch abandonment and recurrence. We observed high patch abandonment (37.5% of used patches)
6 months after Hurricane Wilma and low rates of recurrence (38.1% of abandoned patches) 2 years after the storm, an indication
that this storm further threatened marsh rabbit viability. We found the proportion of salt-tolerant (e.g., mangroves and scrub
mangroves) and salt-intolerant (e.g., freshwater wetlands) vegetation within LKMR patches were negatively and positively correlated
with probability of patch abandonment, respectively. We found patch size and the number of used patches surrounding abandoned
patches were positively correlated with probability of recurrence. We suggest habitat use following this hurricane was driven
by the differential response of non-primary habitats to saline overwash and habitat loss from past development that reduced
the size and number of local populations. Our findings demonstrate habitat use studies should be conducted following disturbance
and should incorporate on-going effects of development and climate change. 相似文献
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Jaime Olivares Perez Francisca Aviles Nova Benito Albarran Portillo Octavio A Castelan Ortega Saul Rojas Hernandez 《Tropical animal health and production》2013,45(3):821-828
Chemical composition, in vitro gas production with and without polyethyleneglycol (PEG-4000 MW), and in vitro digestibility of dry matter (IVDMD) and organic (IVOMD) foliage from Pithecellobium dulce, Gliricidia sepium and Haematoxylum brasiletto were determined. The preference test was run for 15 days: the first 10 days as adaption period and the 5 days served as evaluation period. It was conducted in ten developing female Creole goats of 6 months old, weighing 14?±?2.0 kg in order to determine goat preference for any of the three foliages. Productive performance of 35 male creole kids of 6 months old (14?±?3.0 kg) was also determined by ad libitum feeding of the foliage of the tree: the 30 and 15 % of each of the P. dulce (T1, T2), G. sepium (T3, T4), and H. brasiletto (T5, T6) foliages were added to the experiment diets, while T7 served as control diet that did not contain any foliage. The crude protein (CP), total phenols (TP), condensed tannins (CT), IVDMD, and IVOMD were different among the foliages. The PEG determined the biological activity of the TP and CT of H. brasiletto. Goats preferred to consume the foliage of P. dulce because of its higher content of CP and IVDMD and low content of TP and CT. In the productive response, dry matter intake (DMI) was higher in kids fed T1 diet and was stimulated by higher IVDMD and IVOMD, which resulted in the higher daily weight gain (DWG). The contribution with TP and CT of H. brasiletto to T5 and T6 and the rejection by the animals of G. sepium in T3 and T4 explain the negative effects on the DMI and the DWG. Findings of the study suggested higher kid performance for P. dulce foliage. Possible attributes may include its better CP, low TP and CT, and higher digestibility. 相似文献