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101.
Georg Zizka 《当今生物学》2017,47(1):40-45
Citizen science Citizen science is performed on a honorary basis. Citizen scientists (”Citizen Science proper“) have no professional employment in the relevant field of research and differ very much in their educational background, specific knowledge and amount of time dedicated to the subject of research. Today, citizen science has become especially important in some fields neglected by professional science, e.g. regional research. Recently, another form of citizen science has gained much attention, in which usually many citizen scientist are active (”Citizen Science light“). Internet, smartphone and georeferencing by GPS are important tools for collecting, documenting and communicating the observation data. Besides the scientific results, social relevance through participation and information of citizens (e.g. for conservation issues) play a very important role in these projects. The recently strongly increasing interest in and contribution to citizen science plays an important role to strengthen the link and communication between science and society. 相似文献
102.
This study evaluated the climate change vulnerability of Himalayan communities, and their potential to adapt to these changes, through assessing their perceived reactions and counter-actions to climate change. The evaluation was conducted through proposing and testing indices for vulnerability (Climate Vulnerability Index – CVI) and adaptation (Current Adaptive Capacity Index – CACI) based on the assumption that a community is an active dynamic entity and has tremendous capability to address the impacts of climate change through an ability to make adjustments based on perceived experiences. Both CVI and CACI include the five forms of capital leading to sustainable livelihood, i.e. human, natural, financial, social and physical capital, and were assessed for each of these forms of capital based on the IPCC framework of vulnerability assessment and its three dimensions (exposure, sensitivity, adaptive capacity). Data for the analysis were collected from randomly selected households located away from district headquarters (ADH) and near district headquarters (NDH). Each dimension was measured based on associated socio-environment-specific indicators for assessing vulnerability and sustainability at community level. The results showed that ADH households had higher human capital and natural capital vulnerability than NDH households. In contrast, NDH households had higher social capital and financial capital vulnerability than ADH households. Overall, ADH households had greater vulnerability than NDH households.These results improve understanding of the environmental and socio-economic changes affecting rural livelihoods and the measures needed to address their specific vulnerabilities by addressing bottlenecks in education and training facilities for skill up-grading, increasing interaction opportunities through local functions and creating opportunities for income generation and effective market and farm linkages. An attempt was made to reduce the gap between bottom-up understanding and top-down policies by suggesting precautionary and ongoing adaptation practices for the communities studied, leading to effective and efficient addressal of vulnerabilities. Vulnerability in the study context was taken to mean externally driven change leading to disturbance in the human environment that could alter internal and external livelihood settings. 相似文献
103.
Peng-Fei Yan Ling Yan Ting-Ting Hu Dong-Dong Xiao Zhen Zhang Hong-Yang Zhao Jun Feng 《Translational oncology》2017,10(4):570-577
OBJECT: Preoperative knowledge of meningioma grade is essential for planning treatment and surgery. The purpose of this study was to investigate the diagnostic value of MRI texture and shape analysis in grading meningiomas. METHODS: A surgical database was reviewed to identify meningioma patients who had undergone tumor resection between January 2015 and December 2016. Preoperative MR images were retrieved and analyzed. Texture and shape analysis was conducted to quantitatively evaluate tumor heterogeneity and morphology. Three machine learning classifiers were trained with these features to build classification models. The performance of the features and classification models was assessed. RESULTS: A total of 131 patients were included in this study: 21 with high-grade meningiomas and 110 with low-grade meningiomas. Three texture features were selected: Horzl_RLNonUni, S(2,2)SumOfSqs, and WavEnHL_s-3; three shape features were selected: GeoFv, GeoW4, and GeoW5b. The Mann–Whitney test indicated that all six features were significantly different between high-grade and low-grade meningiomas. AUC values were generally greater than 0.50 (range, 0.73 to 0.88). Sensitivities and specificities ranged from 47.62% to 90.48% and 69.09% to 96.36%, respectively. Among the nine classification models obtained, the one built by training the SVM classifier with all six features achieved the best performance, with a sensitivity, specificity, diagnostic accuracy, and AUC of 0.86, 0.87, 0.87, and 0.87, respectively. CONCLUSIONS: Texture and shape analysis, especially when combined with a SVM classifier, can provide satisfactory performance in the preoperative determination of meningioma grade and is thus potentially useful for clinical application. 相似文献
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105.
Question: Is post‐fire, medium‐term vegetation dynamics determined by land‐use or fire history prior to fire? Location: South‐facing slope in the Gallinera valley, Alicante province, eastern Spain. Methods: After mapping the land‐use and fire history of the study site using photo‐interpretation, we sampled vegetation structure on a set of plots representing the most frequent land‐use and fire history combinations on an area burned six years before sampling. We studied the effects of land‐use history, comparing the one‐fire land‐use trajectories. We analysed the effects of fire history; comparing one‐ and two‐fire plots for both previously cropped and uncropped areas. Results: Most variables were not significantly different between the earliest abandoned plots (abandoned at least 38 years before the fire) and the uncropped plots. On the most recently abandoned plots (abandoned between one and four years before the fire), the therophyte richness and the ratio of seeder: resprouter richness were significantly greatest. Different fire recurrences did not determine different post‐fire vegetation on either the uncropped or the early abandoned plots (all dominated by fire‐recruited seeder shrubs). The most recently abandoned plots had a lower resilience to fire. Conclusions: Land‐use history and recent pre‐fire land use, in particular, determined the post‐fire vegetation in the medium term. The vegetation composition converged during secondary succession among land‐use histories. Increasing fire recurrence had a small effect on mature plant communities, due to the combination of life‐history traits determining the response to fire of the dominant species. 相似文献
106.
107.
This study investigated beliefs about climate change among Swedish secondary school students at the end of their K-12 education. An embedded mixed method approach was used to analyse 51 secondary school students’ written responses to two questions: (1) What implies climate change? (2) What affects climate? A quantitative analysis of the responses revealed that ‘Earth’, ‘human’ and ‘greenhouse effect’ were frequent topics regarding the first question, and ‘pollution’, ‘atmosphere’ and ‘Earth’ were frequent regarding the second. A qualitative analysis, based on a ‘conceptual elements’ framework, focused on three elements within responses: atmosphere (causes and/or consequences), Earth (causes and consequences) and living beings (humans and/or animals and their impacts on climate change). It revealed a predominantly general or societal, rather than individual, perspective underlying students’ responses to the second question. The ability to connect general/societal issues with individual issues relating to climate change could prompt students to reflect on the contributions of individuals towards climate change mitigation, thereby constituting a basis for decision-making to promote a sustainable environment. Although the students did not discuss climate changes from an individual perspective, their statements revealed their understanding of climate change as a system comprising various components affecting the overall situation. They also revealed an understanding of the difference between weather and climate. 相似文献
108.
109.
Frazer J. Bye Linge Wang Anthony J. Bullock Keith A. Blackwood Anthony J. Ryan Sheila MacNeil 《Journal of visualized experiments : JoVE》2012,(66)
Electrospinning is a commonly used and versatile method to produce scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo undergo biaxial distension to varying extents such as skin, bladder, pelvic floor and even the hard palate as children grow. In producing scaffolds for these purposes there is a need to develop scaffolds of appropriate biomechanical properties (whether achieved without or with cells) and which are sterile for clinical use. The focus of this paper is not how to establish basic electrospinning parameters (as there is extensive literature on electrospinning) but on how to modify spun scaffolds post production to make them fit for tissue engineering purposes - here thickness, mechanical properties and sterilisation (required for clinical use) are considered and we also describe how cells can be cultured on scaffolds and subjected to biaxial strain to condition them for specific applications.Electrospinning tends to produce thin sheets; as the electrospinning collector becomes coated with insulating fibres it becomes a poor conductor such that fibres no longer deposit on it. Hence we describe approaches to produce thicker structures by heat or vapour annealing increasing the strength of scaffolds but not necessarily the elasticity. Sequential spinning of scaffolds of different polymers to achieve complex scaffolds is also described. Sterilisation methodologies can adversely affect strength and elasticity of scaffolds. We compare three methods for their effects on the biomechanical properties on electrospun scaffolds of poly lactic-co-glycolic acid (PLGA).Imaging of cells on scaffolds and assessment of production of extracellular matrix (ECM) proteins by cells on scaffolds is described. Culturing cells on scaffolds in vitro can improve scaffold strength and elasticity but the tissue engineering literature shows that cells often fail to produce appropriate ECM when cultured under static conditions. There are few commercial systems available that allow one to culture cells on scaffolds under dynamic conditioning regimes - one example is the Bose Electroforce 3100 which can be used to exert a conditioning programme on cells in scaffolds held using mechanical grips within a media filled chamber.4 An approach to a budget cell culture bioreactor for controlled distortion in 2 dimensions is described. We show that cells can be induced to produce elastin under these conditions. Finally assessment of the biomechanical properties of processed scaffolds cultured with or without cells is described. 相似文献
110.
以《亚热带植物科学》2005~2009年刊载的学术论文数据为样本,采用文献计量学方法,对其近五年的载文、作者、被引、出版时滞等数量指标进行统计分析。2005~2009年《亚热带植物科学》总载文量为463篇,期均发文23.2篇,每篇页数为3.60页。其中,基金资助论文数277篇,基金论文比为59.83%。研究报告是该刊重点栏目,论文篇数占载文量的71.92%,且比重正在加大。论文的出版时滞最长为400 d,最短20 d,平均170.6 d。对该刊论文作者的分析表明,作者合著率较高,为86.18%,但核心作者发文量不多,且其论文质量有待提高。为此,文章对今后编辑工作提出一些改善建议。 相似文献