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1.
Wenjun Geng Jinggong Xiangyu Xiuzhen Li Zhongning Zhang Deyuan Han Yongwei Li 《Insect Science》1997,4(4):364-368
Abstract Field trials by sex pheromone of aphid to trap peach aphids Myzus persicae have been carried out in 1995 and in 1996. Suitable time and the effect of ratio of two components nepetalactone and nepetalactol to apply the lure have been observed. 相似文献
2.
Weixiao Lei Zefu Wang Man Cao Hui Zhu Min Wang Yi Zou Yunchun Han Dandan Wang Zeyu Zheng Ying Li Bingbing Liu Dafu Ru 《DNA research》2022,29(3)
Sophora japonica is a medium-size deciduous tree belonging to Leguminosae family and famous for its high ecological, economic and medicinal value. Here, we reveal a draft genome of S. japonica, which was ∼511.49 Mb long (contig N50 size of 17.34 Mb) based on Illumina, Nanopore and Hi-C data. We reliably assembled 110 contigs into 14 chromosomes, representing 91.62% of the total genome, with an improved N50 size of 31.32 Mb based on Hi-C data. Further investigation identified 271.76 Mb (53.13%) of repetitive sequences and 31,000 protein-coding genes, of which 30,721 (99.1%) were functionally annotated. Phylogenetic analysis indicates that S. japonica separated from Arabidopsis thaliana and Glycine max ∼107.53 and 61.24 million years ago, respectively. We detected evidence of species-specific and common-legume whole-genome duplication events in S. japonica. We further found that multiple TF families (e.g. BBX and PAL) have expanded in S. japonica, which might have led to its enhanced tolerance to abiotic stress. In addition, S. japonica harbours more genes involved in the lignin and cellulose biosynthesis pathways than the other two species. Finally, population genomic analyses revealed no obvious differentiation among geographical groups and the effective population size continuously declined since 2 Ma. Our genomic data provide a powerful comparative framework to study the adaptation, evolution and active ingredients biosynthesis in S. japonica. More importantly, our high-quality S. japonica genome is important for elucidating the biosynthesis of its main bioactive components, and improving its production and/or processing. 相似文献
3.
Due to resource scarcity and environmental degradation, a new development concept emphasizing environmental concerns, called the circular economy (CE), has been enacted in legislation in China. This environmental management concept can be implemented at three levels, namely, region, industrial zone, and individual enterprise, with the objective of boosting economic development while lessening environmental and resource challenges. Environmental supply chain cooperation (ESCC), an approach that utilizes customer and supplier cooperation in environmental management, has been initiated among Chinese enterprises. Using survey data collected from 396 Chinese manufacturers, we examine the role of ESCC practices in influencing the relationship between implementing CE practices and the achievement of performance outcomes by testing the moderation and mediation effects of ESCC practices on the CE practice‐performance relationship through hierarchical regression analysis. Our data analyses indicate that ESCC practices are useful by moderation and, in some cases, essential by mediation, for Chinese manufacturers seeking to realize the performance targets desired in CE practices. The results highlight the need for Chinese manufacturers to improve supply chain coordination in their implementation of CE. On the policy side, our research findings suggest that ESCC practices are beneficial and, in some cases, necessary for the development of CE in China. 相似文献
4.
The Tibetan Plateau is an essential area to study the potential feedback effects of soils to climate change due to the rapid rise in its air temperature in the past several decades and the large amounts of soil organic carbon (SOC) stocks, particularly in the permafrost. Yet it is one of the most under-investigated regions in soil respiration (Rs) studies. Here, Rs rates were measured at 42 sites in alpine grasslands (including alpine steppes and meadows) along a transect across the Tibetan Plateau during the peak growing season of 2006 and 2007 in order to test whether: (1) belowground biomass (BGB) is most closely related to spatial variation in Rs due to high root biomass density, and (2) soil temperature significantly influences spatial pattern of Rs owing to metabolic limitation from the low temperature in cold, high-altitude ecosystems. The average daily mean Rs of the alpine grasslands at peak growing season was 3.92 μmol CO(2) m(-2) s(-1), ranging from 0.39 to 12.88 μmol CO(2) m(-2) s(-1), with average daily mean Rs of 2.01 and 5.49 μmol CO(2) m(-2) s(-1) for steppes and meadows, respectively. By regression tree analysis, BGB, aboveground biomass (AGB), SOC, soil moisture (SM), and vegetation type were selected out of 15 variables examined, as the factors influencing large-scale variation in Rs. With a structural equation modelling approach, we found only BGB and SM had direct effects on Rs, while other factors indirectly affecting Rs through BGB or SM. Most (80%) of the variation in Rs could be attributed to the difference in BGB among sites. BGB and SM together accounted for the majority (82%) of spatial patterns of Rs. Our results only support the first hypothesis, suggesting that models incorporating BGB and SM can improve Rs estimation at regional scale. 相似文献
5.
Two novel aminooligosaccharides were separated from the culture filtrate of Streptomyces coelicoflavus ZG0656. Their chemical structures were determined by electrospray ionization tandem mass spectrometry (ESI-MS/MS) and 2D nuclear magnetic resonance (NMR) spectroscopy. Because of their acarviosine core structures, the names acarviostatins II23 and II13 were given to the novel compounds. The two acarviostatins were both mixed noncompetitive inhibitors of porcine pancreatic alpha-amylase (PPA), with inhibition constants (K(i)) of 0.009 microM (acarviostatin II23) and 0.010 microM (acarviostatin II13). Therefore, acarviostatin II23 and acarviostatin II13 are, respectively, 231 and 208 times more potent than acarbose. 相似文献
6.
7.
Yan Zhang Zhaoming Dong Dandan Wang Yong Wu Qianru Song Peiming Gu Ping Zhao Qingyou Xia 《Amino acids》2014,46(4):1021-1031
The silkworm, Bombyx mori, is an important economic insect for its production of silk. The larvae of many lepidopteran insects are major agricultural pests and often silkworm is explored as a model organism for other lepidopteran pest species. The hemolymph of caterpillars contains a lot of nutrient and immune components. In this study, we applied liquid chromatography–tandem mass spectrometry to gain a better understanding of the larval hemolymph proteomics in B. mori. We identified 752 proteins in hemolymph collected from day-4 fourth instar and day-7 fifth instar. Nearly half the identified proteins (49 %) were predicted to function as binding proteins and 46 % were predicted to have catalytic activities. Apolipophorins, storage proteins, and 30K proteins constituted the most abundant groups of nutrient-storage proteins. Of them, 30K proteins showed large differences between fourth instar larvae and fifth instar larvae. Besides nutrient-storage proteins, protease inhibitors are also expressed very highly in hemolymph. The analysis also revealed lots of immunity-related proteins, including recognition, signaling, effectors and other proteins, comprising multiple immunity pathways in hemolymph. Our data provide an exhaustive research of nutrient-storage proteins and immunity-related proteins in larval hemolymph, and will pave the way for future physiological and pathological studies of caterpillars. 相似文献
8.
Background and Purpose
Growing evidence has emerged and controversial results reported on possible relationship between aspirin use and lung cancer risk. We, therefore, conducted this updated and comprehensive meta-analysis to evaluate this issue, with focus on dose-risk and duration-risk relationships.Methods
We searched electronic databases including PUBMED, EMBASE and Cochrane library to identify eligible studies. Relative risk (RR) and its 95% confidence interval (CI) were used for cohort studies, while odds ratio (OR) were employed for case-control studies. The random effects and fixed effects models were used for analyses.Results
18 studies were identified including 19835 lung cancer cases, which were eligible for inclusion in the present meta-analysis. Pooled data from case-control studies showed a significant inverse association between regular aspirin use and lung cancer risk. But for cohort studies, insignificant association was detected with little evidence of heterogeneity (RR: 1.05, 95%CI: 0.95 – 1.16; I2: 10.3%, p value: 0.351). In case-control studies, standard aspirin use (>325mg) was related to lower lung cancer incidence, compared with low-dose aspirin use (75–100mg). A similar trend was observed in cohort studies. Besides, when analysis was restricted to long time regular aspirin use (>5 years), insignificant results were reported in both cohort and case-control studies. Finally, regular aspirin use might result in higher reduction of non-small cell lung cancer incidence among men.Conclusions
Our findings do not support the protective effect of regular aspirin use on lung cancer risk. Long time aspirin use, sex, dose and type of lung cancer might alter the effect of aspirin use on lung cancer risk. More well-designed studies are needed to further clarify these associations. 相似文献9.
西南岩溶地区黄荆和檵木叶片结构对其生态环境的响应 总被引:3,自引:0,他引:3
应用常规石蜡切片法对生长于桂林毛村岩溶区和非岩溶区的黄荆(Vitex negundo)和檵木(Loropetalumchinense)的解剖特征进行了比较研究,并对两区的黄荆叶片表皮形态进行了扫描电镜观察.结果显示:(1)两地的黄荆叶片背面均有浓密的绒毛,但致密程度有差异,岩溶区黄荆叶片的气孔深藏于绒毛间隙,这种结构可减少水分蒸发,降低因岩溶干旱带来的水分缺失.(2)岩溶区黄荆和檵木的叶片厚度、上下表皮厚度、栅栏组织的厚度以及栅栏组织的致密程度均大于非岩溶区,这些特征有利于减少水分蒸腾.(3)岩溶区黄荆和檵木叶片的维管组织发达程度高于非岩溶区,有利于在蒸腾减小的情况下促进水分运输和营养元素的迁移,说明2种植物叶片结构特征在不同生境区的改变是其长期在岩溶区干旱环境条件下形成的适应性变化. 相似文献
10.
Indigenous ecological knowledge and natural resource management in the cultural landscape of China’s Hani Terraces 总被引:1,自引:0,他引:1
Yuanmei Jiao Xiuzhen Li Luohui Liang Kazuhiko Takeuchi Toshiya Okuro Dandan Zhang Lifang Sun 《Ecological Research》2012,27(2):247-263
Indigenous ecological knowledge (IEK) can contribute to the management of local ecosystems and landscapes. Cultural landscapes
are produced by and reflect the long-term interactions between humans and nature in indigenous societies. Yunnan Province,
located in southwestern China, is the homeland of many ethnic groups, and is also a refuge for numerous species of wild plants
and animals. Indigenous people in Yunnan, who have rich ecological knowledge, play an important role in the conservation of
local biodiversity and the region’s unique terraced agricultural landscapes. We used the Hani people and their outstanding
cultural landscape of rice terraces in Yuanyang County of Yunnan Province as a case study to describe their worldview and
discuss their formation of IEK; their roles in the preservation of rice landraces and in pest regulation; their management
of water, forest, and soil resources; and the vertical landscape pattern and resource-circulation system that has evolved
in the areas managed by the Hani. We also discuss the challenges and threats facing the Hani, their IEK, and their cultural
landscape, as well as discuss the potential for integration of the Hani’s IEK with modern conservation efforts. 相似文献