Large-scale inference in the focally damaged human brain

Clinical outcomes in focal brain injury reflect the interactions between two distinct anatomically distributed patterns: the functional organisation of the brain and the structural distribution of injury. The challenge of understanding the functional architecture of the brain is familiar; that of understanding the lesion architecture is barely acknowledged. Yet, models of the functional consequences of focal injury are critically dependent on our knowledge of both. The studies described in this thesis seek to show how machine learning-enabled high-dimensional multivariate analysis powered by large-scale data can enhance our ability to model the relation between focal brain injury and clinical outcomes across an array of modelling applications. All studies are conducted on internationally the largest available set of MR imaging data of focal brain injury in the context of acute stroke (N=1333) and employ kernel machines at the principal modelling architecture. First, I examine lesion-deficit prediction, quantifying the ceiling on achievable predictive fidelity for high-dimensional and low-dimensional models, demonstrating the former to be substantially higher than the latter. Second, I determine the marginal value of adding unlabelled imaging data to predictive models within a semi-supervised framework, quantifying the benefit of assembling unlabelled collections of clinical imaging. Third, I compare high- and low-dimensional approaches to modelling response to therapy in two contexts: quantifying the effect of treatment at the population level (therapeutic inference) and predicting the optimal treatment in an individual patient (prescriptive inference). I demonstrate the superiority of the high-dimensional approach in both settings

How has the Internet Impacted on Traditional Journalism in the Context of China?

Two dimensions are cross-applied to discuss the effect of the internet on contemporary journalism. On the one hand, new technologies, including the internet, have influenced journalism as a whole and challenged, to some extent, its pre-existing forms. On the other hand, it is only to be expected that the effect of a new technology is shaped by the economic and political context in which this new technology works. Within these theoretical parameters, this study aims to explore the perceptions of Chinese journalists about their own experience of practice in order to assess the extent to which internet technology has impacted on traditional journalism in the context of China. Qualitative semi-structured interviews are used as the research method in this study to collect data from 25 news media professionals, including those who work for traditional news media and those who work for the online news media. Thematic analysis is used as the approach to analyse the qualitative data generated from the interviews. In preparation, a pilot study was used to test the validity of interview questions and the possible thematic codes before the formal study. The quality of the views provided by Chinese journalists can reveal much about the contemporary practice, role perceptions and values of Chinese journalism which cannot currently be found in literature and official reports. By conducting thematic analysis, the gap between existing journalism theories and Chinese specific context can be complemented by the discussion of the emergent core themes

Analysis of ecosystem resilience in Jiuzhaigou Valley Scenic Area under the effect of geohazards

The effects of geohazards on the ecological environment and ecological spatial pattern have received wide attention from scholars. However, the positive role played by ecological restoration projects on the environment and in the reduction of geohazards has usually been neglected. Jiuzhaigou Valley Scenic Area is a world natural heritage area, has a high incidence of geohazards, and is a demonstration area for ecological restoration projects. Based on remote sensing technology, this paper adopted an InVEST model (Integrated Valuation of Ecosystem Services and Tradeoffs) and ecological landscape index to extract information about spatio-temporal changes in Jiuzhaigou from 2013 to 2020. This study utilized a quantitative analysis of the ecological recoverability of Jiuzhaigou in cases of artificial restoration and spontaneous restoration under different types of geohazards. Results showed that forests play a vital role in maintaining and controlling habitat quality; artificial restoration can significantly ameliorate the impact of geohazards on the scenic area. As of 2020, the forested scenic area recovered 3.868 km2, and the habitat quality index rebounded to 98.88% of the historical high. The ecological restoration project significantly shortened the scenic area recover time of its ecosystem service capability

Bayesian data analysis for Gaussian process tomography

Bayesian inference is used in many scientific areas as a conceptually well-founded data analysis framework. In this paper, we give a brief introduction to Bayesian probability theory and its application to the tomography problem in fusion research by means of a Gaussian process prior. This Gaussian process tomography (GPT) method is used for reconstruction of the local soft X-ray (SXR) emissivity in WEST and EAST based on line-integrated data. By modeling the SXR emissivity field in a poloidal cross-section as a Gaussian process, Bayesian SXR tomography can be carried out in a robust and extremely fast way. Owing to the short execution time of the algorithm, GPT is an important candidate for providing real-time feedback information on impurity transport and for fast MHD control. In addition, the Bayesian formulism allows for uncertainty analysis of the inferred emissivity

Effect of zero valent metals and water miscible solvents on reductive dechlorination of polychlorinated biphenyls

The use of polychlorinated biphenyl (PCBs) was discontinued in the 1970\u27s; however, PCB contamination of soils and sediment remains widespread. Many physical, chemical, and biological methods have been developed and evaluated for PCB degradation in the past three decades. Due to PCB\u27s low aqueous solubility, high sorption affinity, recalcitrance and environmental persistence, environmental PCB remediation continues to be economically prohibitive. The use of zero valent iron (ZVI) in dechlorination of PCBs has been reported in several solution systems, but the effectiveness of ZVI to degrade sorbed PCBs has not been addressed in the literature to date. This research focused on developing a zero valent metal (ZVM) system that would be feasible for PCB dechlorination in sediment and soils. PCB dechlorination using nano-scale ZVMs (Fe 0, Zn0, Al0, Fe/Pd, Fe/Ag, Fe/Cu, Fe/Pt) combined with various cosolvents (tetrahydrofuran, ethanol, and acetone) were explored in soil-free and Aroclor 1242 contaminated sediment systems. Fe, Zn, and Al degraded highly chlorinated congeners to less chlorinated congeners. Bimetals, except for Fe/Pt, completely degraded 2,3,4,6-PCB, but at various rates. The dechlorination pathway was affected by the ZVM, not the cosolvent. Nano-scale Fe/0.5% Pd in 30% acetone completely dechlorinated Aroclor 1242 within two minutes in solution, and less than three days in a sediment system. Recoveries of biphenyl and chloride were 90.1 ± 2.3% and 74.4 ± 14.5%, respectively, in solution; and 82% and 56%, respectively, in the sediment. Aroclor 1242 removal increased with increasing percentage of Pd and metal to soil ratio. Aqueous chloride and bromide at seawater concentrations reduced removal of Aroclor 1242 with acetone-Fe/Pd system from 89.3% to 18.0% and 9.4%, respectively. In a bench-scale feasibly test simulating a confined storage facilities (CSF) with Aroclor 1242 contaminated sediment, were 82.2 ± 4.5% and 56.3 ± 15.2% of PCBs were degraded in 28 days in an aqueous and 30% acetone Fe/0.5% Pd system, respectively. This research identified an environmentally friendly Fe/Pd-cosolvent system that has a high potential to be a feasible alternative technology for in-situ and ex-situ remediation of PCB contaminated soils and sediments

Analysis of Virtual Water Trade Flow and Driving Factors in the European Union

The inefficient application of water resources has become an urgent problem restricting the world’s sustainable development. Virtual Water Trade opens a new perspective on improving water resource utilization efficiency. Based on a multi-regional input–output model and the logarithmic mean Divisia index, the virtual water flows between 2000–2014 in 43 countries and regions have been evaluated, and the driving forces of changes in virtual water flows for the European Union were revealed. During the study period, the total amount of virtual water flow continued to increase. The United Kingdom is a net virtual water importer that depends on the European Union significantly. There was a large amount of virtual water flow from the European Union to the United States during 2000–2012. However, China gradually seized the share of virtual water from European Union exports after 2012. Economic effects and virtual water intensity effects are the most significant drivers of virtual water flows. The difference is that the economic effect positively drives virtual water flows, while the virtual water intensity effect negatively influences. The results reveal the nature of the United Kingdom in the virtual water trade and can provide post-Brexit recommendations

Cost-effective polymer-based membranes for drinking water purification

Global water scarcity is exacerbating owing to climate change and pollution, making the demand for clean water more challenging with the growth of the global economy and population. Membrane filtration technologies have been widely applied in drinking water purification due to their energy efficiency while facing challenges like fouling, degradation and trade-offs, such as selectivity and permeability. The sustainable development of our society demands further understanding and improvement of those membranes. In this review, the basic structures of polymer-based water purification membranes including the effective layer for separation, the support layer and the possible top protective layer are presented. Details include the conventional membranes for microfiltration (MF) and ultrafiltration (UF), the effective layers for separation in thin-film composite (TFC) membranes, electrospun nanofibrous membranes for MF, UF, and membrane distillation (MD), as well as the emerging self-assembled block copolymer membranes. Furthermore, the conventional support layers and electrospun nanofibrous support layers for reverse osmosis (RO) and forward osmosis (FO) processes, and the top protective layers are discussed. The materials, membrane structures and properties, modification strategies, possible interlayers, interconnects, interpenetration, and interactions between different layers are discussed, with the emphasis on the cost-effectiveness of various membranes

Numerical Research of an Ice Accretion Delay Method by the Bio-Inspired Leading Edge

The accumulation of ice on aircraft is a typical meteorological issue. The ice accretion on the wing’s leading edge can cause an earlier stall and significantly increase the safety risks. Because the equivalent shape of the wing will change based on the ice pattern on the leading edge, it is crucial to predict the ice pattern of the aircraft and design the anti-icing device. The ice accretion is predicted in the present work through a multi-shot approach. In the current study, a bio-inspired leading edge that can generate multiple pairs of counter-rotating vortices is used to alter the trajectory of the water droplets. This results in a lowering of the ratio of droplet attachment on the leading edge, hence and the ice accretion time, which is an indication of hazardous flight conditions, can be delayed. As a result, the spanwise continuous ice transforms into the discontinuous ice. Meanwhile, the Procrustes analysis provides a result for the thickness of the ice pattern on the wing model based on a variety of parameters for the leading edge