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21.
Introduced by Bishop et al. in 1996, Generative Topographic Mapping (GTM) is a powerful nonlinear latent variable modeling approach for visualizing high-dimensional data. It has shown useful when typical linear methods fail. However, GTM still suffers from drawbacks. Its complex parameterization of data make GTM hard to fit and sensitive to slight changes in the model. For this reason, we extend GTM to a visual analytics framework so that users may guide the parameterization and assess the data from multiple GTM perspectives. Specifically, we develop the theory and methods for Visual to Parametric Interaction (V2PI) with data using GTM visualizations. The result is a dynamic version of GTM that fosters data exploration. We refer to the new version as V2PI-GTM. In this paper, we develop V2PI-GTM in stages and demonstrate its benefits within the context of a text mining case study. 相似文献
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Little of the historical extent of tallgrass prairie ecosystems remains in North America, and therefore there is strong interest in restoring prairies. However, slow‐growing prairie plants are initially weak competitors with the fast‐growing yet short‐lived weedy plant species that are typically abundant in recently established prairie restorations. One way to aid establishment of slow‐growing plant species is through adding soil amendments to prairie restorations before planting. Arbuscular mycorrhizal (AM) fungi form mutualisms with the roots of most terrestrial plants and are particularly important for the growth of slow‐growing prairie plant species. As prairie ecosystems are adapted to fires that leave biochar (charred organic material) in the soil, adding biochar as well as AM fungal strains from undisturbed remnant prairies into the soil of prairie restorations may improve restoration outcomes. Here, we test this prediction during the first four growing seasons of a prairie restoration. When prairie plant seedlings were inoculated prior to planting into the field with AM fungi derived from remnant prairies, that one‐time inoculation significantly increased growth of five of the nine tested plant species through at least two growing seasons. This long‐term benefit of AM fungal inoculation was unaffected by biochar addition to the soil. Biochar application rates of at least 10 tons/ha significantly decreased Coreopsis tripteris growth but acted synergistically with AM fungal inoculation to significantly improve survival of Schizachyrium scoparium. Overall, inoculation with native AM fungi can help promote prairie plant establishment, but concomitant use of biochar soil amendments had relatively little effect. 相似文献
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Leon Danon Jonathan M. Read Thomas A. House Matthew C. Vernon Matt J. Keeling 《Proceedings. Biological sciences / The Royal Society》2013,280(1765)
A major goal of infectious disease epidemiology is to understand and predict the spread of infections within human populations, with the intention of better informing decisions regarding control and intervention. However, the development of fully mechanistic models of transmission requires a quantitative understanding of social interactions and collective properties of social networks. We performed a cross-sectional study of the social contacts on given days for more than 5000 respondents in England, Scotland and Wales, through postal and online survey methods. The survey was designed to elicit detailed and previously unreported measures of the immediate social network of participants relevant to infection spread. Here, we describe individual-level contact patterns, focusing on the range of heterogeneity observed and discuss the correlations between contact patterns and other socio-demographic factors. We find that the distribution of the number of contacts approximates a power-law distribution, but postulate that total contact time (which has a shorter-tailed distribution) is more epidemiologically relevant. We observe that children, public-sector and healthcare workers have the highest number of total contact hours and are therefore most likely to catch and transmit infectious disease. Our study also quantifies the transitive connections made between an individual''s contacts (or clustering); this is a key structural characteristic of social networks with important implications for disease transmission and control efficacy. Respondents'' networks exhibit high levels of clustering, which varies across social settings and increases with duration, frequency of contact and distance from home. Finally, we discuss the implications of these findings for the transmission and control of pathogens spread through close contact. 相似文献
26.
J. Rapkin K. Jensen S. M. Lane C. M. House S. K. Sakaluk J. Hunt 《Journal of evolutionary biology》2016,29(2):395-406
Sexual conflict results in a diversity of sex‐specific adaptations, including chemical additions to ejaculates. Male decorated crickets (Gryllodes sigillatus) produce a gelatinous nuptial gift (the spermatophylax) that varies in size and free amino acid composition, which influences a female's willingness to fully consume this gift. Complete consumption of this gift maximizes sperm transfer through increased retention of the sperm‐containing ampulla, but hinders post‐copulatory mate choice. Here, we examine the effects of protein (P) and carbohydrate (C) intake on the weight and amino acid composition of the spermatophylax that describes its gustatory appeal to the female, as well as the ability of this gift to regulate sexual conflict via ampulla attachment time. Nutrient intake had similar effects on the expression of these traits with each maximized at a high intake of nutrients with a P : C ratio of 1 : 1.3. Under dietary choice, males actively regulated their nutrient intake but this regulation did not coincide with the peak of the nutritional landscape for any trait. Our results therefore demonstrate that a balanced intake of nutrients is central to regulating sexual conflict in G. sigillatus, but males are constrained from reaching the optima needed to bias the outcome of this conflict in their favour. 相似文献
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随着全球建造业向数字化全面转型,建筑信息模型(BIM)的教学将是未来几年风景园林设计与实施的重要主题。介绍了风景园林专业BIM的教学方法和数字化竖向设计及其应用在BIM场地设计项目中的重要性。数字化竖向设计是实现BIM的途径。风景园林教育必须在其教学中讲解BIM建模方法和过程。 相似文献
28.
Chen B Chen J House MG Cullen KJ Nephew KP Guo Z 《Molecular cancer research : MCR》2012,10(3):305-315
Resistance to cisplatin-based chemotherapy is responsible for therapeutic failure of many common human cancers including cancer of head and neck (HNC). Mechanisms underlying cisplatin resistance remain unclear. In this study, we identified neurofilament light polypeptide (NEFL) as a novel hypermethylated gene associated with resistance to cisplatin-based chemotherapy in HNC. Analysis of 14 HNC cell lines revealed that downregulation of NEFL expression significantly correlated with increased resistance to cisplatin. Hypermethylation of NEFL promoter CpG islands was observed in cell lines as examined by bisulfite DNA sequencing and methylation-specific PCR (MSP) and tightly correlated with reduced NEFL mRNA and protein expression. Furthermore, in patient samples with HNC (n = 51) analyzed by quantitative MSP, NEFL promoter hypermethylation was associated with resistance to cisplatin-based chemotherapy [relative risk (RR), 3.045; 95% confidence interval (CI), 1.459-6.355; P = 0.007] and predicted diminished overall and disease-free survival for patients treated with cisplatin-based chemotherapy. Knockdown of NEFL by siRNA in the highly cisplatin-sensitive cell line PCI13 increased (P < 0.01) resistance to cisplatin. In cisplatin-resistant O11 and SCC25cp cells, restored expression of NEFL significantly increased sensitivity to the drug. Furthermore, NEFL physically associated with tuberous sclerosis complex 1 (TSC1), a known inhibitor of the mTOR pathway, and NEFL downregulation led to functional activation of mTOR pathway and consequentially conferred cisplatin resistance. This is the first study to show a role for NEFL in HNC chemoresistance. Our findings suggest that NEFL methylation is a novel mechanism for HNC chemoresistance and may represent a candidate biomarker predictive of chemotherapeutic response and survival in patients with HNC. 相似文献
29.
CH Balachiranjeevi Naik S. Bhaskar V. Abhilash S. Akanksha B. C. Viraktamath M. S. Madhav A. S. Hariprasad G. S. Laha M. S. Prasad S. M. Balachandran C. N. Neeraja M. Satendra Kumar P. Senguttuvel K. B. Kemparaju V. P. Bhadana T. Ram G. Harika H. K. Mahadeva Swamy S. K. Hajira A. Yugander K. Pranathi M. Anila G. Rekha M. B. V. N. Kousik T. Dilip Kumar R. K. Swapnil Archana Giri R. M. Sundaram 《Molecular breeding : new strategies in plant improvement》2015,35(7):1-12
30.
The Contribution of Agriculture,Forestry and other Land Use activities to Global Warming, 1990–2012 下载免费PDF全文
Francesco N. Tubiello Mirella Salvatore Alessandro F. Ferrara Jo House Sandro Federici Simone Rossi Riccardo Biancalani Rocio D. Condor Golec Heather Jacobs Alessandro Flammini Paolo Prosperi Paola Cardenas‐Galindo Josef Schmidhuber Maria J. Sanz Sanchez Nalin Srivastava Pete Smith 《Global Change Biology》2015,21(7):2655-2660
We refine the information available through the IPCC AR5 with regard to recent trends in global GHG emissions from agriculture, forestry and other land uses (AFOLU), including global emission updates to 2012. Using all three available AFOLU datasets employed for analysis in the IPCC AR5, rather than just one as done in the IPCC AR5 WGIII Summary for Policy Makers, our analyses point to a down‐revision of global AFOLU shares of total anthropogenic emissions, while providing important additional information on subsectoral trends. Our findings confirm that the share of AFOLU emissions to the anthropogenic total declined over time. They indicate a decadal average of 28.7 ± 1.5% in the 1990s and 23.6 ± 2.1% in the 2000s and an annual value of 21.2 ± 1.5% in 2010. The IPCC AR5 had indicated a 24% share in 2010. In contrast to previous decades, when emissions from land use (land use, land use change and forestry, including deforestation) were significantly larger than those from agriculture (crop and livestock production), in 2010 agriculture was the larger component, contributing 11.2 ± 0.4% of total GHG emissions, compared to 10.0 ± 1.2% of the land use sector. Deforestation was responsible for only 8% of total anthropogenic emissions in 2010, compared to 12% in the 1990s. Since 2010, the last year assessed by the IPCC AR5, new FAO estimates indicate that land use emissions have remained stable, at about 4.8 Gt CO2 eq yr?1 in 2012. Emissions minus removals have also remained stable, at 3.2 Gt CO2 eq yr?1 in 2012. By contrast, agriculture emissions have continued to grow, at roughly 1% annually, and remained larger than the land use sector, reaching 5.4 Gt CO2 eq yr?1 in 2012. These results are useful to further inform the current climate policy debate on land use, suggesting that more efforts and resources should be directed to further explore options for mitigation in agriculture, much in line with the large efforts devoted to REDD+ in the past decade. 相似文献