Diversity and evolution of samara in angiosperm北大核心CSCD

Samara (winged fruit) can be dispersed easily by wind and may be a crucial factor for angiosperm spread and diversification. In a narrow sense, a samara is an indehiscent dry fruit with wing(s) developed from fruit pericarp, while in a broad sense samaras also include all winged fruits with wings developed from both pericarp and peri-anth or bracts. According to the wing shape and growth patterns of samaras, we divided samaras into six types, i.e. single-winged, lanceolate-winged, rib-winged, sepal-winged, bract-winged, and perigynous samaras. Perigynous samaras can be further classified into two forms, i.e. round-winged and butterfly-winged samaras. Accordingly, the aerodynamic behavior of samaras can be classified into five types, autogyro, rolling autogyro, undulator, helicopter, and tumbler. The rib-winged and round-winged samaras can be found in Laurales, a basal angiosperm, and may represent the primitive type of early samaras. In the derived clades, samaras evolved enlarged but unequal wings and decreased wing loading (the ratio of fruit weight to wing size), which is likely an adaptation to gentle wind and secondary dispersal through water or ground wind. The wings of some samaras (such as sepal-winged and bract-winged samaras) may have multiple functions including wind dispersal, physical defense for the seeds, and adjust seed germination strategy. The pantropical family Malpighiaceae is extraordinarily rich in samara types, which is likely related to its multiple inter-continent dispersal in history, which is known as “Malpighiaceae Route”. Therefore, Malpighiaceae can be used as a model system for the studies on samara adaptation and evolution. We identified the following issues that deserve further examination in future studies using both ecological and evo-devo methods: 1) the adaption of different types of samaras in dispersal processes, 2) the molecular and developmental mechanism of sepal- and bract-wings, and 3) the evolution of samara types and their effects on angiosperm diversification. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved.     

Where's the ecology in molecular ecology?

Molecular techniques have had a profound impact in biology. Major disciplines, including evolutionary biology, now consistently utilize molecular tools. In contrast, molecular techniques have had a more limited impact in ecology. This discrepancy is surprising. Here, we describe the unexpected paucity of ecological research in the field colloquially referred to as 'molecular ecology.' Publications over the past 15 years from the journals Ecology , Evolution and Molecular Ecology reveal that much of the research published under the molecular ecology banner is in fact evolutionary in nature, and that comparatively little ecological research incorporates molecular tools. This failure to more broadly utilize molecular techniques in ecology is alarming because several promising lines of ecological inquiry could benefit from molecular approaches. Here we summarize the use of molecular tools in ecology and evolution, and suggest several ways to renew the ecological focus in 'molecular ecology'.     

An update of the vegetation classification in China北大核心CSCD

The vegetation classification in China was updated by referring to recent advances for vegetation classification worldwide and on the basis of our former paper Recognition and Proposal on the Vegetation Classification System of China (hereafter, "Recognition and Proposal"). In this revision, the criteria for vegetation classification were discussed and unified, and a quantified standard for high, medium, and low level units in a new hierarchical classification scheme was supplemented. Compared with the old classification scheme in "Recognition and Proposal", the units at the level of vegetation type were substantially changed. Finally, in order to improve mutual communication among international peers, a comparison was carried out between the new revised scheme and each of International Classification and Mapping of Vegetation of UNESCO, The National Vegetation Classification Standard of United States, and The Braun-Blanquet Classification Scheme.     

A review of the calibration methods for measuring the carbon and oxygen isotopes in CO2 based on isotope ratio infrared spectroscopy北大核心CSCD

With the development of isotope ratio infrared spectroscopy (IRIS) technology, it is now possible for the in situ high temporal resolution and high precision measurement of carbon isotopic composition (d13C) and oxygen isotopic composition (d18O) of atmospheric CO2, which overcomes the low temporal resolution and labor intensive shortcoming of traditional isotope ratio mass spectrometry (IRMS). The dependence of d13C and d18O on CO2 concentration (termed as concentration dependence) and the drift due to sensitivity to changing environmental conditions (termed as instrumental drift) are the two main sources of error affecting the IRIS measurements. Therefore, it is important to obtain precise measurements by constructing a proper calibration strategy to solve the concentration dependence and instrumental drift. In this study, we briefly discussed the definition and related theoretical principle of concentration dependence, and elaborated the theoretical and empirical calibration methods of concentration dependence. Moreover, we introduced the calibration methods of instrumental drift, and reviewed the state of the art of calibration methods and its application of IRIS technology. Additionally, we briefly discussed the definition and method of data traceability to the international standard, and reviewed its application of IRIS technology. Finally, we recommend that concentration dependence is corrected by using three standards or above with known CO2 concentration and its d13C and d18O, bracketing the CO2 concentration of samples. The instrumental drift is corrected by setting appropriate calibration frequency and all dataset are traceable to the international standard. In the future, the comparative study of different IRIS instruments and calibration methods should be enhanced, and the similar methods should be used for measuring CH4, N2O and H2O isotopes by IRIS technique. The IRIS technology combined with other technology will provide a new opportunity for ecological research. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved.     

Carbon storage,spatial distribution and the influence factors in Tianshan forests北大核心CSCD

Aims Accurate estimation of carbon density and storage is among the key challenges in evaluating ecosystem carbon sink potentials for reducing atmospheric CO2 concentration. It is also important for developing future conservation strategies and sustainable practices. Our objectives were to estimate the ecosystem carbon density and storage of Picea schrenkiana forests in Tianshan region of Xinjiang, and to analyze the spatial distribution and influencing factors. Methods Based on field measurements, the forest resource inventories, and laboratory analyses, we studied the carbon storage, its spatial distribution, and the potential influencing factors in Picea schrenkiana forest of Tianshan. Field surveys of 70 sites, with 800 m2 (28.3 m × 28.3 m) for plot size, was conducted in 2011 for quantifying arbor biomass (leaf, branch, trunk and root), grass and litterfall biomass, soil bulk density, and other laboratory analyses of vegetation carbon content, soil organic carbon content, etc. Important findings The carbon content of the leaf, branch, trunk and root of Picea schrenkiana is varied from 46.56% to 52.22%. The vegetation carbon content of arbor and the herbatious/litterfall layer was 49% and 42%, respectively. The forest biomass of Picea schrenkiana was 187.98 Mg•hm2, with 98.93% found in the arbor layer. The biomass in all layers was in the order of trunk (109.81 Mg•hm2) > root (39.79 Mg•hm2) > branch (23.62 Mg•hm2) > leaf (12.76 Mg•hm2). From the age-group point of view, the highest and the lowest biomass was found at the mature forest (228.74 Mg•hm2) and young forest (146.77 Mg•hm2), respectively. The carbon density and storage were 544.57 Mg•hm2 and 290.84 Tg C, with vegetation portion of 92.57 Mg•hm2 and 53.14 Tg C, and soil portion of 452.00 Mg•hm2 and 237.70 Tg C, respectively. The spatial distribution of carbon density and storage appeared higher in the western areas than those in the eastern regions. In the western Tianshan Mountains (e.g., Ili district), carbon density was the highest, whereas the central Tianshan Mountains (e.g., Manas County, Fukang City, Qitai County) also had high carbon density. In the eastern Tianshan Mountains (e.g., Hami City), it was low. This distribution seemed consistent with the changes in environmental conditions. The primary causes of carbon density difference might be a combined effects of multiple environmental factors such as terrain, precipitation, temperature, and soil.     

Comparison of methods for detecting vulnerability of xylem embolism in Robinia pseudoacacia北大核心CSCD

Aims The vulnerability of xylem embolism is one of the key physiological factors that are related to plant mortality. Vulnerability curves are typically used for determining the vulnerability of xylem embolism. However, the shapes of vulnerability curves vary with the methods of assessment, especially in plant species with long xylem vessels. This study aims to investigate the feasibility of using different methods for establishment of vulnerability curves. Methods Robinia pseudoacacia branches, with long xylem vessels, were used as plant materials for comparison of three different methods in establishing vulnerability curves, including bench top dehydration, Cochard Cavitron centrifugation and Sperry centrifugation. In the Sperry centrifugation method, rotors of two different sizes were used to test the ‘open vessel artifact’ hypothesis. Important findings The vulnerability curve established by the bench top dehydration method displayed an “s” shape, while both the Cochard Cavitron centrifugation and Sperry centrifugation methods produced “r” shape curves. Vulnerability curves derived from the bench top dehydration method and the centrifugation methods were significantly different. Using the Sperry centrifugation method, the R. pseudoacacia branch samples in the 14.4 cm rotor had a higher proportion of open vessels, while the embolic vulnerability curves established on the 27.4 cm and 14.4 cm long stem segments were similar, indicating that the Sperry centrifugation method does not produce “open vessel artifact”. © Chinese Journal of Plant Ecology.     

Ion mapping in plant cells – methods and applications in signal transduction research

 This review covers both methodical aspects and actual applications of ion imaging techniques in plant cell signal research. The methodological section explains the basic principles of fluorescence ion imaging, the impact of modern developments in fluorescence microscopy and introduces the most important fluorescence probes including aequorin and other photoproteins. It critically comments on loading strategies, intracellular compartmentation of probes and calibration procedures. The second part compiles actual research areas where the application of ion imaging procedures has gained substantial achievements and helped to establish new concepts of calcium- and pH-dependent signalling. Examples comprise the hormonal control of stomatal movements, effects of gibberellic and abscisic acids in aleurone cells, elicitation of phytoalexin production, cytosolic pH and cell development, and signatures of Ca²⁺ as a universal signal in plant cells. Received: 26 May 1999 / Accepted: 2 August 1999     

成都地奥集团北大核心CSCD

成都地奥集团是1988年8月18日借款50万元创办的高新技术企业,经过20多个春秋的不懈努力,已成为集天然药物、合成药物、基因工程药物、微生物药物、药物制剂研制为一体的大型骨干制药企业,是国内实力最强的药物研制、中试、生产基地之一,是世界上最大的高纯度甾体皂苷和高纯度胸腺肽生产企业,矿业能源领域极具发展潜力的生力军。地奥集团已拥有四个制药企业、一个药品销售公司、一个医药连锁销售公司、一个化妆品生产企业、一个保健品(含化妆品)销售公司、一个矿业能源公司、     

成都地奥集团北大核心CSCD

成都地奥集团是1988年8月18日借款50万元创办的高新技术企业,经过20多个春秋的不懈努力,已成为集天然药物、合成药物、基因工程药物、微生物药物、药物制剂研制为一体的大型骨干制药企业,是国内实力最强的药物研制、中试、生产基地之一,是世界上最大的高纯度圍体皂苷和高纯度胸腺肽生产企业,矿业能源领域     

导读北大核心CSCD

本期导读主题:基因诊断技术、抗新冠抗体药物、高通量药物筛选技术、纳米抗体、多组学肿瘤药物敏感性预测、植物质体转基因技术、肠道微生物与疾病。以基因工程为基础、细胞工程为导向的现代生物技术在医药领域的广泛应用,被称之为现代医药生物技术。现代医药生物技术在疾病的诊断、预防和治疗及生物技术药物的研发中的应用,促进了诸如传染病、恶性肿瘤、心脑血管疾病等重大疾病在诊断、预防、治疗上的技术革命,已成长为现代工业的支柱产业之一的生物医药产业,服务于人类的健康事业。     

成都地奥集团北大核心CSCD

成都地奧集团是1988年8月18日借款50万元创办的高新技术企业,经过20多个春秋的不懈努力,已成为集天然药物、合成药物、基因工程药物、微生物药物、药物制剂研制为一体的大型骨干制药企业,是国内实力最强的药物研制、中试、生产基地之一,是世界上最大的高纯度甾体皂苷和高纯度胸腺肽生产企业,矿业能源领域极具发展潜力的生力军。     

成都地奥集团北大核心CSCD

成都地奥集团是1988年8月18日借款50万元创办的高新技术企业,经过20多个春秋的不懈努力,已成为集天然药物、合成药物、基因工程药物、微生物药物、药物制剂研制为一体的大型骨干制药企业,是国内实力最强的药物研制、中试、生产基地之一,是世界上最大的高纯度甾体皂苷和高纯度胸腺肽生产企业,矿业能源领域极具发展潜力的生力军。地奥集团已拥有四个制药企业、一个药品销售公司、一个医药连锁销售公司、一个化妆品生产企业、一个保健品(含化妆品)销售公司、一个矿业能源公司、一个房地产公司等共计11家下属企业和控股企业,现有     

声明北大核心CSCD

<正>中国科学院微生物所期刊联合编辑部编辑出版有《微生物学报》、《菌物学报》、《微生物学通报》和《生物工程学报》四种期刊,凡向本编辑部投稿,均视为同意在本编辑部网站及CNKI中国期刊全文数据库等数据库出版,所付稿酬包含网络出版稿酬。     

声明北大核心CSCD

<正>中国科学院微生物研究所期刊联合编辑部编辑出版有《微生物学报》、《菌物学报》、《微生物学通报》和《生物工程学报》4种期刊(按创刊时间排序),凡向本编辑部投稿,均视为同意在本编辑部网站及CNKI中国期刊全文数据库等数据库出版,所付稿酬包含网络出版稿酬。     

更正北大核心CSCD

朱玥荃,王文恭,薛丽香.一种新型SUMO E3连接酶CBX4的化学修饰作用[J].中国生物化学与分子生物学报,2016,32(2):115-122.该文3.2部分(119页)"因此这样就形成了一个CBX4与底物作用蛋白质之间化学修饰的反馈调节环路(Fig.4)"更改为"因此这样就形成了一个CBX4与底物作用蛋白质之间化     

CO2 flux dynamics and its limiting factors in the alpine shrub-meadow and steppe-meadow on the Qinghai-Xizang Plateau北大核心CSCD

Aims Alpine shrub-meadows and steppe-meadows are the two dominant vegetation types on the Qinghai-Xizang Plateau, and plays an important role in regional carbon cycling. However, little is known about the temporal- spatial patterns and drivers of CO2 fluxes in these two ecosystem types. Methods Based on five years of consecutive eddy covariance measurements (2004-2008) in an eastern alpine shrub-meadow at Haibei and a hinterland alpine steppe-meadow at Damxung, we investigated the seasonal and annual variation of net ecosystem productivity (NEP) and its components, i.e. gross primary productivity (GPP) and ecosystem respiration (Re). Important findings The CO2 fluxes (NEP, GPP and Re) were larger in the shrub-meadow than in the steppe-meadow during the study period. The shrub-meadow functioned as a carbon sink through the five years, with the mean annual NEP of 70 g C·m-2·a-1. However, the steppe-meadow acted as a carbon neutral, with mean annual NEP of -5 g C·m-2·a-1. The CO2 fluxes of steppe-meadow exhibited large variability due to the inter-Annual and seasonal variations in precipitation, ranging from a carbon sink (54 g C·m-2·a-1) in 2008 to a carbon source (-88 g C·m-2·a-1) in 2006. The differences in carbon budget between the two alpine ecosystems were firstly attributed to the discrepancy of normalized difference vegetation index (NDVI) because NDVI was the direct factor regulating the seasonal and inter-Annual NEP. Secondly, the shrub-meadow had higher carbon use efficiency (CUE), which was substantially determined by annual precipitation (PPT) and NDVI. Our results also indicated that the environmental drivers of CO2 fluxes were also different between these two alpine ecosystems. The structure equation model analyses showed that air temperature (Ta) determined the seasonal variations of CO2 fluxes in the shrub-meadow, with NEP and GPP being positively correlated with Ta. By contrast, the seasonal CO22 fluxes in the steppe-meadow were primarily co-regulated by soil water content (SWC) and Ta, and increased with the increase of SWC and Ta. In addition, the changes of Re during the growing season in two ecosystems were directly affected by GPP and soil temperature at 5 cm depth (Ts), while Re during non-growing season were determined by Ts. These results demonstrate that the synergy of soil water and temperature played crucial roles in determining NEP and GPP of the two alpine meadows on the Qinghai-Xizang Plateau. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved.     

Characteristic and representativeness of the vertical vegetation zonation along the altitudinal gradient in Shennongjia Natural Heritage北大核心CSCD

Aims Mountains contain broad environmental gradients, which are to be an outstanding universal value representing significant on-going ecological and biological processes in the evolution and development of zonal vegetation along the elevation gradients. Exploring the biological and ecological value of the vegetation zonation along the elevation gradients of Chinese mountain natural heritage site is important for biodiversity conservation and management. Methods Based on the community survey data of the six vegetation zonation along the elevational gradients in Shennongjia, the global land use dataset, and the literature data of the communities along the altitudinal gradients of other natural heritage sites and the nominated world natural heritage sites in Oriental Deciduous Forest Biogeographic Province by Udvardy, we explored the outstanding universal value of the zonal vegetation along the altitude gradients by the methods of spatial analysis. Important findings Shennongjia heritage site preserves the intact vegetation zonation of the typical Oriental Deciduous Forest Biogeographical Province in the Classification of the Biogeographical Provinces of the World by Udvardy, including evergreen broad-leaved forests (South Slope of the Heritage Site), evergreen deciduous broad-leaved mixed forests, deciduous broad-leaved forests, coniferous and broad-leaved mixed forests, coniferous forests and subalpine shrub and meadow along the elevation gradients. The altitudinal zonation of vegetation in the Shennongjia heritage site represented a variety of bio-ecological processes, such as the turnover of the dominant trees along the altitudinal gradients, and is an outstanding example of the ongoing ecological processes occurring in the development of intact subtropical mixed broadleaved evergreen and deciduous forest in the Northern Hemisphere. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All Rights Reserved.     

Host cell protein analysis in therapeutic protein bioprocessing – methods and applications

The analysis of host cell proteins (HCPs) is one of the most important analytical requirements during bioprocess development of therapeutic moieties. In this review, we focus on the comparison of different methods for the analysis of HCPs and how cell lines, fermentation conditions, and unit operations influence HCP distribution during the process chain. Current guidelines typically require reduction of HCPs to the ppm level, depending on the intended use, the route of administration of the product, and the production system. A range of immunospecific and non-specific methods are available that have been globally accepted by regulatory bodies. Immunospecific methods, such as ELISA, are simple to use in routine analysis and can quantify low levels of HCPs when specific antibodies are available. Non-specific methods are more complex; however, they provide a holistic view of the HCP profile and qualitative information of the composition of HCP in the sample. Different methods for the comparison of bioprocessing strategies during scale-up and purification development are compared herein. The methods include immunospecific methods, such as ELISA, western blot, and threshold, and non-specific methods, such as 2D-DIGE and 2D-HPLC combined with MS.