Beetle’s responses to edges in fragmented landscapes are driven by adjacent farmland use,season and cross-habitat movement     

Katherina Ng  Philip S. Barton  Sarina Macfadyen  David B. Lindenmayer  Don A. Driscoll 《Landscape Ecology》2018,33(1):109-125

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Erosive polyarthritis associated with Mycoplasma gateae in a cat     

Zeugswetter F  Hittmair KM  de Arespacochaga AG  Shibly S  Spergser J 《Journal of Feline Medicine and Surgery》2007,9(3):226-231

Erosive polyarthritis was diagnosed in an 11-month-old neutered male Egyptian Mau-cross cat with concurrent glucocorticoid-responsive dermatitis. Clinical signs, synovial fluid analysis, serological tests and radiographic appearance could not differentiate between immune-mediated and infective arthritis. Mycoplasma gateae was isolated by strictly anaerobic culture of the synovial fluid. Treatment with Enrofloxacin led to a rapid improvement of the cat's condition. Two months later the cat was euthanased because of severe glomerulonephritis and direct Coombs' test positive anaemia, possibly caused by mycoplasma infection. M gateae could not be isolated at post-mortem examination.  相似文献   

Spectral separability and mapping potential of cassava leaf damage symptoms caused by whiteflies (Bemisia tabaci)          下载免费PDF全文

Neil C Sims  Paul De Barro  Glenn J Newnham  Andrew Kalyebi  Sarina Macfadyen  Tim J Malthus 《Pest management science》2018,74(1):246-255

BACKGROUND

This study examines whether leaf spectra can be used to measure damage to cassava plants from whitefly (Bemisia tabaci), and the potential to translate measurements from leaf to landscape scale in eastern Africa. Symptoms of the cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) viruses, and sooty mould (SM) blackening of lower leaves from whiteflies feeding on the upper leaves, were measured at the leaf scale with a high‐resolution spectroradiometer and a single photon avalanche diode (SPAD) meter, which retrieves relative chlorophyll concentration. Spectral measurements were compared to the five‐level visual scores used to assess the severity of each of the three damaging agents in the field, and also to leaf chemistry data.

RESULTS

Leaves exhibiting severe CBSD and CMD were spectrally indistinguishable from leaves without any symptoms. Severe SM was spectrally distinctive but is likely to be difficult to map because of its occurrence in the lower crown. SPAD measurements were highly correlated with most foliar chemistry measurements and field scores of disease severity. Regression models between simulated Sentinel 2 bands, field scores and SPAD measurements were strongest using wavelengths with high importance weightings in random forest models.

CONCLUSION

SPAD measurements are highly correlated to many foliar chemistry parameters, and should be considered for use in mapping disease severity over larger areas. Remaining challenges for mapping relate to the subtle expression of symptoms, the spatial distribution of disease severity within fields, and the small size and complex structure of the cassava fields themselves. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

绵羊上皮细胞三种纯化与培养方法的比较研究   总被引：1，自引：0，他引：1  

袁荣华  白萨日娜  曹贵方 《畜牧与饲料科学》2006,27(5):28-29

为了探索一种简便、高纯度分离子宫内膜腺上皮细胞和间质细胞的方法,以及建立高纯度体外子宫内膜细胞培养模型,该试验将原代细胞的3种培养方法,即组织块贴壁法、胰蛋白酶消化法和胶原蛋白酶消化法进行比较,结果表明胶原蛋白酶消化法对细胞的损伤小,细胞生长良好,相比较而言使用胶原蛋白酶消化法最理想。  相似文献   

Effect of Biofumigants on Soil Microbial Communities and Ecotoxicology of Earthworms (<Emphasis Type="Italic">Eisenia andrei</Emphasis>)     

Tanya?Fouché  Mark?Maboeta  Sarina?ClaassensEmail authorView author&#;s OrcID profile 《Water, air, and soil pollution》2016,227(8):256

Biofumigation is considered a good alternative to chemical fumigation because it can control crop pathogens and diseases with lower health and environmental risks than chemical fumigants. Glucosinolates are volatile compounds found in most Brassica species, and when hydrolysed, it forms a range of natural toxins including isothiocyanates that act as biofumigants. However, the effect of glucosinolates and their breakdown products on non-target and beneficial soil organisms is not well documented. Three biofumigants, broccoli, mustard and oilseed radish, were evaluated for their effect on earthworms (Eisenia andrei) and the soil microbial community. Sub-lethal endpoints, including growth and reproductive success of the earthworms, were monitored. Genotoxicity of the biofumigants towards earthworms was evaluated by means of the comet assay. Broccoli reduced earthworm reproduction while mustard induced more DNA strand breaks in earthworm cells compared to the control. Soil microbial community function and structure were evaluated by means of community level physiological profiling and phospholipid fatty acid analyses. The effects exerted by the biofumigants on the microbial community were the most pronounced within the first 14 days after application. Carbon substrate utilisation was most affected by the oilseed radish treatment and microbial community structure by the mustard treatment.  相似文献   

内蒙古通辽市霜冻期规律初探   总被引：1，自引：0，他引：1  

邰文河  邢明华  萨日娜  贺俊艳  白晓慧 《畜牧与饲料科学》2011,(8):21-22

通过分析1971—2009年内蒙古通辽市初霜冻期、终霜冻期及无霜期序列,初步探讨了它们的变化趋势、分布频率等气候特征,指出了初霜期推迟、终霜期提前、无霜期延长的变化趋势,而这种变化趋势与气候变暖理论相一致。  相似文献   

17β-雌二醇对绵羊输卵管上皮细胞β-防御素-2(SBD-2)表达的影响     

包图雅  纳仁高娃  白萨日娜  李雅静  杨燕燕 《畜牧与饲料科学》2015,(1)

[目的]探讨17β-雌二醇(E2)对体外培养的绵羊输卵管上皮细胞内抗菌肽SBD-2基因表达的影响。[方法]根据E2添加剂量设10-6mol/L组、10-7mol/L组、10-8mol/L组、10-9mol/L组和10-10mol/L组,各组细胞于加药后2、6、12、24及48 h,分别采用real-time RT-PCR技术检测E2对绵羊输卵管上皮细胞内SBD-2 m RNA表达量的影响,同时设相应的对照组。[结果]以剂量为10-8mol/L的E2处理输卵管上皮细胞6 h后,其SBD-2的表达量达到极值,极显著高于对照组(P0.01),以剂量为10-10mol/L的E2处理输卵管上皮细胞24 h和48 h后,也能显著促进SBD-2的表达(P0.01,P0.05),之后随着各时间段E2剂量的增加,SBD-2 m RNA的表达量呈逐渐降低趋势。[结论]一定剂量的E2能够在处理细胞后的特定时间促进绵羊输卵管上皮细胞中SBD-2 m RNA的表达,E2对输卵管上皮细胞SBD-2 m RNA表达的调节作用存在时间效应与剂量依赖关系。  相似文献   

Effect of support medium,hydraulic loading rate and plant density on water quality and growth of halophytes in marine aquaponic systems          下载免费PDF全文

Suzanne E Boxman  Michael Nystrom  Joseph C Capodice  Sarina J Ergas  Kevan L Main  Maya A Trotz 《Aquaculture Research》2017,48(5):2463-2477

The development of marine intensive land‐based aquaculture systems has been limited due to the absence of methods to manage saline wastewater. Aquaponic systems, although commonly applied to freshwater aquaculture, can potentially manage nutrient wastes while providing a secondary product. The aim of this study was to evaluate both the capacity for water treatment and the production requirements of two saltwater‐tolerant plant species (Sesuvium portulacastrum and Batis maritima) when grown hydroponically in a marine aquaponic system. The presence of plants was found to significantly contribute to nitrate removal, such that mean nitrate concentrations were 10.1 ± 5.4 and 12.1 ± 6.1 mg/L NO₃^?‐N in planted and unplanted treatments respectively. The use of coconut fibre as a planting medium also significantly contributed to nitrate removal, such that mean nitrate concentrations were 9.78 ± 5.4 and 12.4 ± 6.0 mg/L NO₃^?‐N in coconut fibre and expanded clay treatments respectively. Daily nitrogen removal was greatest in the coconut fibre/plants treatment, ranging from ?18% to 67%. Hydraulic loading rate, plant species and plant density did not significantly affect water quality or plant growth. The low flow/saltwort/low density treatment had the greatest mean daily nitrogen removal, ranging from 25% to 172%. The results indicate that the main nitrogen removal mechanisms were simultaneous nitrification–denitrification in the hydroponic plant beds and nitrogen removal through plant growth. This study demonstrates that marine aquaponics could be an effective way to manage nutrient removal in marine land‐based aquaculture systems.  相似文献   

寒地粳稻耐盐愈伤组织生理特性及再分化研究     

赵宏伟  萨日娜 《东北农业大学学报》2013,(1):24-28

采用逐步提高培养基中NaCl浓度的方法,对寒地粳稻长白3和龙稻9成熟胚诱导出的愈伤组织进行选择培养,研究NaCl对愈伤组织生长量、脯氨酸含量和丙二醛含量的影响规律以及对愈伤组织再分化的影响。结果表明,随着NaCl浓度的升高,2个品种愈伤组织的相对生长量均下降,脯氨酸含量先升高后下降,丙二醛含量先增加后减少再增加,再分化率减少;在不同NaCl浓度处理下,长白3愈伤组织中脯氨酸及丙二醛积累量都高于龙稻9,且在较高NaCl浓度处理下,长白3愈伤组织再分化率低于龙稻9,证明长白3愈伤组织耐盐性低于龙稻9。  相似文献   

Hydraulic compression of mice to 166 atmospheres     

J A Kylstra  R Nantz  J Crowe  W Wagner  H A Saltzman 《Science (New York, N.Y.)》1967,158(802):793-794

Hydraulic uniform compression elicited tremors, uncoordinated limb movements, and tonic convulsions in liquid-breathing mice at pressures ranging from 50 to 100 atmospheres. Such abnormal muscular activity was observed neither in control animals nor in mice caudally to a spinal transection. Uniform compression of isolated preparations of mouse muscle in saline failed to contract at pressures up to 200 atmospheres.  相似文献