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1.
为明确棉铃虫Helicoverpa armigera ATP结合盒转运蛋白家族A蛋白亚家族2（ATP binding cassette transporter subfamily A member 2,ABCA2）在Cry2Ab杀虫机制中的作用,利用酵母双杂交技术研究棉铃虫ABCA2与Cry2Ab的结合特性,并利用RNA干涉（dsRNA和siRNA）降低ABCA2在细胞和幼虫中的表达,结合细胞毒理学试验分析ABCA2的功能。结果表明,棉铃虫ABCA2能与Cry2Ab特异性结合;棉铃虫的ABCA2序列与美洲棉铃虫H.zea相关序列的相似度为92.86%,利用dsRNA干涉美洲棉铃虫中肠细胞ABCA2的表达能显著降低Cry2Ab对中肠细胞的毒力;利用siRNA干涉技术降低ABCA2在棉铃虫幼虫活体中的表达也显著降低了Cry2Ab对幼虫的毒力。表明棉铃虫ABCA2不仅是Cry2Ab的特异性结合蛋白,而且参与Cry2Ab的杀虫过程,是Cry2Ab的一个重要功能受体。 相似文献
2.
Chuyuan Wang Soe W. Myint Peilei Fan Michelle Stuhlmacher Jiachuan Yang 《Landscape Ecology》2018,33(5):765-782
Context
This study examines the spatio-temporal patterns of urban expansion for Yangon and Nay Pyi Taw, the former and new national capitals of Myanmar, and its impact on the regional environment between 2000 and 2013.Objectives
The objective is to examine different driving forces of urban expansion for Yangon and Nay Pyi Taw, and their environmental consequences during Myanmar’s transitional economy.Methods
Classified time-series Landsat images are used to evaluate urban expansion processes. Environmental parameters being evaluated in this study include five sets of remotely sensed MODIS land products that are land surface temperature (LST), percent tree cover (PTC), evapotranspiration (ET), terrestrial ecosystem net primary productivity (NPP), and aerosol optical depth (AOD). A time-series trend analysis technique is used to examine the environmental consequences.Results
The built-up areas in Nay Pyi Taw and Yangon exhibit exponential and polynomial increase, respectively. A 1% increase of built-up area could potentially cause an increase of daytime LST of 0.7 °C, a PTC loss of 2.3%, a decrease in NPP of 34.3 kg/m2, and an ET decrease of 42.2 mm for Yangon. Similarly, for Nay Pyi Taw, a 1% increase in built-up area could potentially cause a daytime LST increase of 0.3 °C, a nighttime LST increase of 0.06 °C, a PTC loss of 2.5%, a decrease in NPP of 15.1 kg/m2, and a decrease of 19.2 mm ET. No significant change was observed for AOD for either city.Conclusions
Both cities have experienced extensive urban expansion but with different spatial and temporal characteristics, and their effects on the regional environment are different. Urban expansion of Nay Pyi Taw mainly was government-induced municipal infrastructure development. Yangon’s expansion is mainly caused by population pressure and migration from rural areas. The urban expansion in Yangon was mainly due to reconstruction and renovation, as well as infill development during the study period.3.
G. Darrel Jenerette Sharon L. Harlan Alexander Buyantuev William L. Stefanov Juan Declet-Barreto Benjamin L. Ruddell Soe Win Myint Shai Kaplan Xiaoxiao Li 《Landscape Ecology》2016,31(4):745-760
Context
With rapidly expanding urban regions, the effects of land cover changes on urban surface temperatures and the consequences of these changes for human health are becoming progressively larger problems.Objectives
We investigated residential parcel and neighborhood scale variations in urban land surface temperature, land cover, and residents’ perceptions of landscapes and heat illnesses in the subtropical desert city of Phoenix, AZ USA.Methods
We conducted an airborne imaging campaign that acquired high resolution urban land surface temperature data (7 m/pixel) during the day and night. We performed a geographic overlay of these data with high resolution land cover maps, parcel boundaries, neighborhood boundaries, and a household survey.Results
Land cover composition, including percentages of vegetated, building, and road areas, and values for NDVI, and albedo, was correlated with residential parcel surface temperatures and the effects differed between day and night. Vegetation was more effective at cooling hotter neighborhoods. We found consistencies between heat risk factors in neighborhood environments and residents’ perceptions of these factors. Symptoms of heat-related illness were correlated with parcel scale surface temperature patterns during the daytime but no corresponding relationship was observed with nighttime surface temperatures.Conclusions
Residents’ experiences of heat vulnerability were related to the daytime land surface thermal environment, which is influenced by micro-scale variation in land cover composition. These results provide a first look at parcel-scale causes and consequences of urban surface temperature variation and provide a critically needed perspective on heat vulnerability assessment studies conducted at much coarser scales.4.
为明确棉铃虫Helicoverpa armigera丝氨酸蛋白酶抑制剂（serine protease inhibitor,serpin）的种类及其表达特性,利用PCR技术克隆棉铃虫的serpin基因,使用生物信息学软件预测其结构并进行系统进化分析,采用实时荧光定量PCR（real time quantitative PCR,RT-qPCR）技术比较serpin基因在棉铃虫不同发育阶段和组织中的表达量及取食Cry1Ac后其表达量的变化。结果表明,共获得serpin-a、serpin-b、serpin-c、serpin-e四个棉铃虫serpin基因,全长为1 119~1 254 bp,编码373~418个氨基酸,均包含一段具有反应中心环的保守结构域,且与斜纹夜蛾Spodoptera litura、草地贪夜蛾S.frugiperda等鳞翅目昆虫serpin的同源性较高。serpin-a和serpin-e在棉铃虫4龄幼虫期的表达量最高,serpin-b和serpin-c分别在成虫期和蛹期表达量最高。serpin-a在中肠和围食膜中表达量最高,serpin-b在头、中肠和表皮中表达量最高,serpin-c在头部表达量最高,serpin-e在中肠和血淋巴中的表达量显著高于其他组织。棉铃虫取食低浓度Cry1Ac后,中肠的serpin-b和serpin-e的表达量显著增加。推测不同serpin基因在棉铃虫不同发育时期和组织中可能发挥不同的作用,其中serpin-b和serpin-e可能参与棉铃虫对Cry1Ac的解毒过程。 相似文献
5.
Nishii N Nodake H Takasu M Soe O Ohba Y Maeda S Ohtsuka Y Honjo T Saito M Kitagawa H 《American journal of veterinary research》2006,67(12):2006-2011
OBJECTIVE: To evaluate postprandial changes in the leptin concentration of CSF in dogs during development of obesity. ANIMALS: 4 male Beagles. PROCEDURES: Weight gain was induced and assessments were made when the dogs were in thin, optimal, and obese body conditions (BCs). The fat area at the level of the L3 vertebra was measured via computed tomography to assess the degree of obesity. Dogs were evaluated in fed and unfed states. Dogs in the fed state received food at 9 AM. Blood and CSF samples were collected at 8 AM, 4 PM, and 10 PM. RESULTS: Baseline CSF leptin concentrations in the thin, optimal, and obese dogs were 24.3 +/- 2.7 pg/mL, 86.1 +/- 14.7 pg/mL, and 116.2 +/- 47.3 pg/mL, respectively. In the thin BC, CSF leptin concentration transiently increased at 4 PM. In the optimal BC, baseline CSF leptin concentration was maintained until 10 PM. In the obese BC, CSF leptin concentration increased from baseline value at 4 PM and 10 PM. Correlation between CSF leptin concentration and fat area was good at all time points. There was a significant negative correlation between the CSF leptin concentration-to-serum leptin concentration ratio and fat area at 4 PM; this correlation was not significant at 8 AM and 10 PM. CONCLUSIONS AND CLINICAL RELEVANCE: Decreased transport of leptin at the blood-brain barrier may be 1 mechanism of leptin resistance in dogs. However, leptin resistance at the blood-brain barrier may not be important in development of obesity in dogs. 相似文献
6.
Soe Toe Toe Thwe Thida Lay Aye Pwint Thu Myint Kyi Thar Lwin Than Than Thaung Ye Win Min Aye Aye Mitsui Shota Terahara Takeshi Endo Masato Yokota Masashi Rahman M. Moshiur Kobayashi Takeshi 《Fisheries Science》2021,87(3):311-320
Fisheries Science - The Silond catfish Silonia silondia, locally known as Nga Myin Yinn, is a commercially important fish in Myanmar; however, fundamental knowledge of its population structure is... 相似文献
7.
In order to substitute the use of chemical fertilizers in legume production, there is a need for the production of rhizobial inoculants which are capable of being used as biofertilizers. To achieve this, an effective symbiotic nitrogen (N) fixation between legumes and root nodule bacteria will be essential. Evaluation of effective Myanmar Bradyrhizobium (Jordan 1982) strains isolated from Myanmar soybean (Glycine max L. Merr.) and effects of coinoculation with Streptomyces griseoflavus Krainsky 1914 P4 for N fixation were studied in pot experiments using sterilized vermiculite and Hoagland solution in the Phytotron (25°C and 70% relative humidity) with completely randomized design and three replicates. N fixation ability of soybean was evaluated by acetylene reduction activity (ARA) by gas chromatography. It was found that MAS23 showed a relatively high degree of stability and a high level of ARA per plant on both Yezin-3 and Yezin-6 soybean varieties. In the symbiotic relationship between Bradyrhizobium strains and P4 experiments, the treatments consisted of six Bradyrhizobium strains (MAS23, MAS33, MAS34, MAS43, MAS48 and USDA110) and Streptomyces griseoflavus P4 were evaluated with four Myanmar soybean varieties (Yezin-3, Yezin-6, Hinthada and Shan Sein). In the Yezin-3 soybean variety, the best treatment for ARA per plant was found in the dual inoculation of P4 and MAS34. In the Yezin-6 soybean variety, the highest nodule dry weight was found in dual inoculation of P4 with MAS34 but the highest ARA per plant was observed in the dual inoculation of P4 and MAS23. On the other hand, single inoculation of MAS43 and coinoculation of P4 with MAS48 were significantly higher in N fixation of Hinthada, and coinoculation of P4 with MAS33 was significant improvement of ARA per plant (P < 0.05) in Shan Sein soybean. 相似文献
8.
氨肽酶N（APN）是锌金属蛋白酶M1家族的成员,鳞翅目昆虫中肠刷状缘膜囊泡（brush border membrane vesicles,BBMV）细胞膜上的APN不仅在蛋白消化吸收过程中起着重要的作用,而且是Bt的重要受体蛋白。本研究通过PCR技术克隆得到7条棉铃虫APN基因全长序列,HaAPN1～7（Genbank登录号为MT002819～MT002825）。经生物信息学分析,HaAPN1～7全长为2592～3099 bp,编码863～1032个氨基酸,分子量为110～115 kDa,等电点为4.7～6.4,N端信号肽为15～20 aa。系统进化分析结果表明,HaAPN1～7分属于Class 1～7类别。RT-qPCR结果表明,在敏感棉铃虫5龄幼虫中肠中APN2的表达量最高,APN7的表达量最低;Cry1Ac抗性品系棉铃虫中各类APN的表达趋势与敏感品系一致。取食Cry1Ac、Cry2Ab和Vip3Aa蛋白后棉铃虫中肠APN活性显著降低,取食Cry1Ac和Vip3Aa蛋白后中肠液和BBMV中APN活性都显著降低,而取食Cry2Ab蛋白后只有BBMV上APN活性显著降低;棉铃虫对Cry1Ac、Cry2Ab和Vip3Aa产生耐受性后,中肠液和BBMV中APN活性也都发生显著变化。因此,不同类别的棉铃虫APN在Bt的杀虫机制中可能起到不同的作用,APN活性变化可能与Bt蛋白的降解及抗性演化相关。 相似文献
9.
Soe W. Myint Elizabeth A. Wentz Anthony J. Brazel Dale A. Quattrochi 《Landscape Ecology》2013,28(5):959-978
We investigate the direct relationship between detailed urban land cover classes, derived from fine resolution QuickBird satellite data, and land surface temperatures (Celsius), generated from ASTER imagery, over Phoenix, Arizona. Using daytime and nighttime temperatures in both winter and summer and all observation points (n = 11,025), we develop linear, non-linear and multiple regression models to explore the relationship. Conventional wisdom suggests that all urban features result in increased temperatures. Rather, our results show that a mass of buildings is not necessarily or holistically responsible for extreme heat in desert cities. It is the construction of other impervious dark surfaces (i.e., asphalt roads) associated with buildings that result in extreme heat. Moreover, our results suggest that buildings, especially commercial buildings with high albedo roofs, actually reduce temperatures. The addition of trees and shrubs, as opposed to grass, around buildings can further mitigate extreme heat by providing more cooling during the summer and increasing nighttime temperatures in the winter. In conclusion, the compositional design of and avoidance of dark impervious materials in desert cities help mitigate extreme temperatures. It is important to note, however, that design choices that reduce extreme heat must be made within the broader context of tradeoffs and unintended consequences to ensure the sustainability of these cities. 相似文献