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991.
包妲  李杰  刘锋  胡金明 《生态学报》2021,41(17):6960-6969
缅甸土地利用变化对其生态系统服务的影响与中缅绿色"一带一路"、中缅经济走廊建设等重大战略的长期合作息息相关。利用缅甸1995年和2015年的土地利用数据,结合Costanza生态系统服务价值系数表,分析缅甸土地利用变化对生态系统服务价值的影响。结果表明:(1)1995-2015年,缅甸土地利用类型以林地(71%)和耕地(26%)为主,林地和草地面积减少,而其他地类增加;林地和耕地之间的转化显著。(2)缅甸生态系统服务价值约4600-4700亿美元,林地贡献最大;调节(48%)和支持(29%)服务价值比重较大;(3)生态系统服务总价值增加了66.26亿美元,调节、供给和支持服务价值增加,而文化服务价值减少;生态系统服务二级类型中:废物处理、食物供给、生境/避难所等增加,气候调节、遗传资源、水土保持功能等减少;(4)缅甸土地利用变化对生态系统服务总价值和生态系统服务一级类型总价值影响较小,但生态系统服务二级类型价值的"此消彼长"会影响缅甸生态安全和生物多样性,在未来中缅"一带一路"建设中需要重点关注。  相似文献   
992.
The conflict between economic growth and the environment is complex and sharper today than ever before. Indeed, the relationship between economic growth and the sustainability of ecosystems has been extensively discussed in the literature, but the results remain controversial.This paper reviews the use of single and composite indicators of environmental damage and questions whether the Environmental Kuznets Curve (EKC) hypothesis sufficiently mirrors the relationship between economic growth and ecological damage. Ecological Indicators are relevant when they potentially inform society about ecological developments in a reliable way. We use the modified composite index of environmental performance (mCIEP) to measure environmental damage, and GDP per capita to represent economic growth. The econometric model is developed using panel data composed of 152 countries and a period of 6 years. The model is estimated for the full sample, for three different sets of countries, by level of development, and a decomposition analysis is carried out, which corresponds to the study of the CIEP individual dimensions.Our results reveal that, at present, the EKC hypothesis is not proved. We conclude that it is critical to be clear that economic growth alone is not enough to improve environmental quality. Therefore, creating a consistent, coherent and effective environmental policy framework is essential in order to improve environmental quality that supports wellbeing and enables long-term economic development.  相似文献   
993.
The excitatory synaptic function is subject to a huge amount of researches and fairly all the structural elements of the synapse are investigated to determine their specific contribution to the response. A model of an excitatory (hippocampal) synapse, based on time discretized Langevin equations (time-step = 40 fs), was introduced to describe the Brownian motion of Glutamate molecules (GLUTs) within the synaptic cleft and their binding to postsynaptic receptors. The binding has been computed by the introduction of a binding probability related to the hits of GLUTs on receptor binding sites. This model has been utilized in computer simulations aimed to describe the random dispersion of the synaptic response, evaluated from the dispersion of the peak amplitude of the excitatory post-synaptic current. The results of the simulation, presented here, have been used to find a reliable numerical quantity for the unknown value of the binding probability. Moreover, the same results have shown that the coefficient of variation decreases when the number of postsynaptic receptors increases, all the other parameters of the process being unchanged. Due to its possible relationships with the learning and memory, this last finding seems to furnish an important clue for understanding the basic mechanisms of the brain activity.  相似文献   
994.

Content of p‐coumaric (PCA) and ferulic (FA) acid was determined by the HPLC method in fourteen forbs with a potential utilization as forages (range of nutrient content per kg DM: 100 to 244gCP, 339 to 528 g NDF and 180–369 g ADF. PCA and FA were determined after methanol extraction in four fractions: free phenolic acids extracted into ether, ester‐bound phenolic acids after alkaline hydrolysis, glycoside‐bound phenolic acids after acid hydrolysis, and cell wall‐bound phenolic acids after alkaline hydrolysis of the solid residue after the extraction with methanol.

Cell wall‐bound phenols were quantitatively the most important fraction (50% of total PCA and 47% of total FA, respectively). The differences among plant species in total PCA plus FA content were significant (F‐value 775, P < 0.01). The range of total phenol content was 31.3 to 416.3 mg/100g DM, the overall mean was 84 mg/100g DM.

Content of phenolic acids was correlated neither with ADF, NDF or ADL content (R 2 = 1–3%, P > 0.05) nor with CP degradability (R 2 = 3% and R 2 = 1% for PCA and FA, respectively, P > 0.05).

95.4% and 30.9% of total PCA, and 98.3% and 72.5% of total FA disappeared in the rumen from the sample of Glechoma hederacea (species with the highest phenol content) and from the sample of Galium aparine (species with low phenol content), respectively, within the four hour incubation interval.

It is presumed that in comparison with grasses, PCA and FA concentration in tested forbs represents a much lower risk in potential ruminant nutrition.  相似文献   
995.
We study height trends among Chinese, South Korean, and Taiwanese groups during the rapid economic growth period of the 1960s to the 1980s. Heights rose strongly as income grew. Did rapid income growth also cause a decline in gender inequality? Or did it rise because the gains were unevenly distributed? Gender inequality is particularly interesting given the traditionally strong son preference in the region. For mainland China, we find that gender inequality was relatively modest in the pre-reform period (before the 1980s). Especially in comparison to the early 20th century, female heights grew faster than male heights. In contrast, the 1980s transition period to an economic system with market elements was characterized by increasing gender inequality in China. This was the case to an even greater extent in South Korea, where gender dimorphism noticeably increased during the 1980s, paralleling a similar increase in sex-selective abortions. Moreover, we also study other inequality patterns in the three countries, focusing on socioeconomic, regional, and educational differences between groups.  相似文献   
996.
We investigate the evolution of an individual's willingness to invest in a public good (what we call, helping) in a patch‐structured population with limited natal dispersal. We assume that an individual's decision to invest is informed by its dispersal status: an individual makes one decision given it is native to the patch on which it breeds, and is free to make a different decision given that it is not native to the patch on which it breeds. Unlike previous work, we assume that investment in the public good, and the public good, itself, both have a large effect on individual fecundity. Kin selection analysis reveals that only extreme investment decisions (i.e. ‘always invest’ or ‘never invest’) can be evolutionarily stable. Numerical results suggest that the evolutionary instability of the ‘never invest’ phenotype (what we call, complete nonhelping) implies the evolutionary stability of ‘always invest’ (what we call, complete helping). In addition, numerical results show that bistability of extreme phenotypes is possible, indicating that the adaptive significance of altruism, in this context, is greater than has been previously recognized. Numerical results are supported by computer simulation, and results, themselves, are briefly discussed in a concluding section.  相似文献   
997.
The physical and sensory characteristics of tomato fruits (cf. Gajc-Wolska et al.: Physical and sensory characteristics of the fruits …, this issue) were supplemented by total sugars and titratable acid analysis and flavor. The instrumental and sensory methods were highly statistically correlated. Comparison of cultivars always requires that physical and chemical analysis of tomato fruit quality should always include results of sensory evaluation.  相似文献   
998.
999.
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Highlights
  • •New comparative tool to assess the relevance of a glycan composition file to be used in a glycoproteomic study.
  • •User-friendly and web-based interface to explore glycoproteomics data.
  • •Detection of glycan compositional trends within and across protein(s) or tissues.
  相似文献   
1000.
The objective of this work was to investigate the evaluation of swine colostrum immunoglobulin G (IgG) concentration using the Brix refractometer. Colostrum samples were collected across all teats, from 124 sows of mixed parities. According to sampling time, three categories were created: samples available from 9 h before the onset of parturition until the first piglet was born were classified as before farrowing; samples collected after the first birth until 4 h later were classified as during farrowing; and finally samples collected from this point until 14 h after parturition, were classified as after farrowing. Samples were drawn and divided into three portions; one was immediately analyzed, a second was refrigerated and the third was frozen at −20°C. Fresh and refrigerated colostrum samples were analyzed at the farm with a Brix refractometer. IgG content of frozen samples was analyzed using a Brix refractometer, with a subset of 42 samples also tested with a commercially available radial immune diffusion (RID) kit. The Brix percentage ranged from 18.3% to 33.2%. Brix percentage repeatability, assessed by the intraclass correlation coefficient (ICC), was very strong (fresh ICC=0.98, refrigerated ICC=0.88 and frozen ICC=0.99). One-way repeated-measures ANOVA showed that storage temperature did not affect BRIX percentage of colostrum IgG (P>0.05). ANOVA results show a significant effect of sampling time on colostrum immunoglobulin concentration, measured with both Brix and RID (Brix: P<0.003; RID: P<0.05). Immunoglobulin G concentration measured by RID ranged from 13.27 to 35.08 mg/ml. Pearson correlation coefficient revealed that Brix percentage was positively correlated (r=0.56, P<0.001) with RID results (regression equation: RID=1.01 (±0.2) Brix −1.94 (±5.66); R2=0.31). The results of this study indicate that the Brix refractometer provides a simple, fast and inexpensive estimation of colostrum IgG in sows.  相似文献   
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