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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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Araújo MA Albuquerque VB Deschk M Santos GG Rodrigues CA Oliva VN Santos PS 《Veterinary anaesthesia and analgesia》2012,39(4):409-413
ObjectiveTo assess cardiopulmonary and analgesic effects after administration of ropivacaine into the caudal epidural space of cattle.Study designProspective, single-dose trial.AnimalsEight healthy mixed breed cows aged 8 ± 5 years and weighing 507 ± 112 kg.MethodsCaudal epidural anesthesia was produced in cows with 0.75% ropivacaine (0.11 mg kg?1). Onset time, duration and cranial spread of analgesia were recorded. Heart rate (HR), respiratory rate (fR), rectal temperature (RT), and mean arterial blood pressure (MAP) were measured prior to epidural administration (T0) and at 15, 30, 60, 120, 180 and 240 minutes after epidural administration (T15, T30, T60, T120, T180 and T240). Arterial blood acid-base balance (pH, standard bicarbonate and base excess), gas tension (PaO2, PaCO2, SaO2) and electrolytes (Na+, K+, iCa2+,Cl?) were recorded at T0, T30, T60, T120, T180 and T240. Ataxia was evaluated at T0, T30, T60, T120, T180 and T240 and at 1 hour intervals thereafter until analgesia was no longer present in each animal.ResultsEpidurally administered ropivacaine induced variable analgesia extending bilaterally from the coccyx to S3. Time to onset of analgesia and mean duration in the perineal area were 15 ± 4 and 359 ± 90 minutes, respectively. Respiratory rate and RT increased from T120 to T240 when compared to the value at T0. Ionized calcium and chloride concentrations increased at T180 and T240 when compared to T0. The other variables were not significantly different from baseline values (p> 0.05). Four animals were mildly ataxic.Conclusion and clinical relevanceRopivacaine (0.75%, 0.11 mg kg?1) can be administered by caudal epidural injection to produce prolonged bilateral perineal analgesia with minimal ataxia and cardiopulmonary changes in standing cattle. 相似文献
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Fabieli Loise Braga Feitosa Angélica Simone Cravo Pereira Sabrina Thaise Amorim Elisa Peripolli Rafael Medeiros de Oliveira Silva Camila Urbano Braz Adrielle Matias Ferrinho Flavio Schramm Schenkel Luiz Fernando Brito Rafael Espigolan Lucia Galvão de Albuquerque Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(5):468-476
The aim of this study was to evaluate the genomic predictions using the single-step genomic best linear unbiased predictor (ssGBLUP) method based on SNPs and haplotype markers associated with beef fatty acids (FAs) profile in Nelore cattle. The data set contained records from 963 Nelore bulls finished in feedlot (±90 days) and slaughtered with approximately 24 months of age. Meat samples from the Longissimus dorsi muscle were taken for FAs profile measurement. FAs were quantified by gas chromatography using a SP-2560 capillary column. Animals were genotyped with the high-density SNP panel (BovineHD BeadChip assay) containing 777,962 markers. SNPs with a minor allele frequency and a call rate lower than 0.05 and 0.90, respectively, monomorphic, located on sex chromosomes, and with unknown position were removed from the data set. After genomic quality control, a total of 469,981 SNPs and 892 samples were available for subsequent analyses. Missing genotypes were imputed and phased using the FImpute software. Haplotype blocks were defined based on linkage disequilibrium using the Haploview software. The model to estimate variance components and genetic parameters and to predict the genomic values included the random genetic additive effects, fixed effects of the contemporary group and the age at slaughter as a linear covariate. Accuracies using the haplotype-based approach ranged from 0.07 to 0.31, and those SNP-based ranged from 0.06 to 0.33. Regression coefficients ranged from 0.07 to 0.74 and from 0.08 to 1.45 using the haplotype- and SNP-based approaches, respectively. Despite the low to moderate accuracies for the genomic values, it is possible to obtain genetic progress trough selection using genomic information based either on SNPs or haplotype markers. The SNP-based approach allows less biased genomic evaluations, and it is more feasible when taking into account the computational and operational cost underlying the haplotypes inference. 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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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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José?Saporiti?Machado Raúl?Albuquerque?SardinhaEmail author Helena?Pires?Cruz 《Wood Science and Technology》2004,38(4):277-284
In order to assess the lengthwise variation of mechanical properties of maritime pine (Pinus pinaster Ait.) a study on the possibility of automatically detecting knots by ultrasonic readings across the grain was carried out. A through-transmission acousto-ultrasonic (AU) setup was implemented allowing acquisition of AU profiles along the central mid-third of each specimen. An algorithm was proposed and successfully implemented for enhancing variations on the AU profiles due to knot presence. Discriminant analysis was applied to the AU profiles. The results show the possibility of automatically differentiating clear wood zones from zones with a knot area ratio value above 20% or 30%, with a success rate of 75% to 83% depending on the dimension of the specimens tested.This research project was supported by the Foundation for Science and Technology (FCT) under contract Nos. PBIC/C/AGR/2296/95 and POCTI/33967/AGR/2000 相似文献