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Voltage source converter‐high voltage direct current (VSC‐HVDC) connections have become a new trend for long‐distance offshore wind power transmission. In order to facilitate the derivation of the feedforward DC voltage control based fault ride through (FRT) technique, this chapter describes the model of a VSC‐HVDC‐connected offshore wind power plant (WPP) with an external grid. It proposes a feedforward DC voltage control based FRT technique to control the AC voltage at the WPP collector network during grid‐side faults. Time‐domain simulations have been used to verify the efficacy of the proposed feedforward DC voltage control based FRT technique for VSC‐HVDC‐connected WPPs. Time‐domain simulation results shows that the proposed FRT scheme can successfully enable VSC‐HVDC‐connected WPPs to ride through balanced and unbalanced faults in host power systems, as well as faults in the WPP collector system, with a fast and robust response.

Expropriation risk has a binding effect on foreign direct investment (FDI). However, state-owned multinational corporations may counter the monopoly power of the host state by leveraging the political influence of their home government. The magnitude of this counter force, we argue, may vary, depending on the strength of political relations between the home and host state, and the level of economic dependence of the host country on the home market. We find supporting evidence of our hypotheses using Chinese firm-level FDI information between 2003 and 2010.

The Wolastoq | Saint John River (W|SJR) in New Brunswick, Canada, is regulated by hydroelectric dams with the largest and furthest downstream being the Mactaquac Generating Station (MQGS). River regulation can disrupt ecosystem connectivity by restricting access to upstream habitat for fishes and parasitic mussel larvae dependent on fishes for dispersal. Following installation of the MQGS, the number of Gaspereau (Alewife, Alosa pseudoharengus [Wilson, 1811]) and Blueback herring, Alosa aestivalis [Mitchill, 1814]) that spawn in that region of theW|SJR has increased dramatically. We assessed ectoparasitic freshwater mussel glochidia on Gaspereau captured at the MQGS and found 100% infested with an average of 43.2 glochidia per fish. Glochidia infested gill rakers, with increasing intensities from the first to fourth gill arch ( P  < 0.001). At least one million Gaspereau are passed above the MQGS annually, suggesting that millions of glochidia are simultaneously passed upstream each year with their hosts. We sequenced mitochondrial markers ( ND1 , COI ) to ascertain mussel species and confirm both Alewife and Blueback herring as hosts for Alewife Floater ( Utterbackiana implicata [Say, 1829]). This study provides critical baseline data on symbiotic interactions tightly interwoven in this river ecosystem and demonstrate that river regulation and fish passage considerations are more complex than most management plans account for currently.

Trans-generational immune priming (TGIP) refers to the transfer of the parental immunological experience to its progeny. This may result in offspring protection from repeated encounters with pathogens that persist across generations. Although extensively studied in vertebrates for over a century, this phenomenon has only been identified 20 years ago in invertebrates. Since then, invertebrate TGIP has been the focus of an increasing interest, with half of studies published during the last few years. TGIP has now been tested in several invertebrate systems using various experimental approaches and measures to study it at both functional and evolutionary levels. However, drawing an overall picture of TGIP from available studies still appears to be a difficult task. Here, we provide a comprehensive review of TGIP in invertebrates with the objective of confronting all the data generated to date to highlight the main features and mechanisms identified in the context of its ecology and evolution. To this purpose, we describe all the articles reporting experimental investigation of TGIP in invertebrates and propose a critical analysis of the experimental procedures performed to study this phenomenon. We then investigate the outcome of TGIP in the offspring and its ecological and evolutionary relevance before reviewing the potential molecular mechanisms identified to date. In the light of this review, we build hypothetical scenarios of the mechanisms through which TGIP might be achieved and propose guidelines for future investigations.

We present a new eye-tracking and target designation device based on a contact lens incorporating a pair of vertical-cavity surface-emitting lasers (VCSELs). We describe the operating principle, the manufacturing process and characterize the impact of the VCSELs encapsulation on their optical properties. We then describe how such device can be incorporated into an eye-wear or a visual augmented system. We compare two different detection set-ups, the first using a camera and the second a position sensitive device, both illustrating different laser beam detection modes. We analyze their performances in terms of angular accuracy, speed, compactness, manufacturability, compared to current conventional eye-tracking systems. We emphasize how the use of two VCSELs and the control of their orientation during the encapsulation can simplify their integration in host systems and improve the gaze detection performance. Finally, we describe various embodiments and discuss potential improvements that can be expected in future systems.

The use of cloud computing data centers is growing rapidly to meet the tremendous increase in demand for high-performance computing (HPC), storage and networking resources for business and scientific applications. Virtual machine (VM) consolidation involves the live migration of VMs to run on fewer physical servers, and thus allowing more servers to be switched off or run on low-power mode, as to improve the energy consumption efficiency, operating cost and CO2 emission. A crucial step in VM consolidation is host overload detection, which attempts to predict whether or not a physical server will be oversubscribed with VMs. In contrast to the majority of previous work which use CPU utilization as the sole indicator for host overload, a recent study has proposed a multiple regression host overload detection algorithm, which takes multiple factors into consideration: CPU, memory and network BW utilization. This paper provides further improvement along two directions. First, we provide Multi-Dimensional Regression Host Utilization (MDRHU) algorithms that combine CPU, memory and network BW utilization via Euclidean Distance (MDRHU-ED) and absolute summation (MDRHU-AS), respectively. This leads to improved results in terms of energy consumption and service level agreement violation. Second, the study explicitly takes real-world HPC workloads into consideration. Our extensive simulation study further illustrates the superiority of our proposed algorithms over existing methods. In particular, as compared to the most recently proposed multiple regression algorithm that is based on Geometric Relation (GR), our proposed algorithms provide an improvement of at least 12% in energy consumption, and an improvement of at least 80% in a metric that combines energy consumption, service-level-violation, and number of VM migrations.

In the rhizosphere, complex and dynamic interactions occur between plants and microbial networks that are primarily mediated by root exudation. Plants exude various metabolites that may influence the rhizosphere microbiota. However, few studies have sought to understand the role of root exudation in shaping the functional capacities of the microbiota. In this study, we aimed to determine the impact of plants on the diversity of active microbiota and their ability to denitrify via root exudates. For that purpose, we grew four plant species, Triticum aestivum, Brassica napus, Medicago truncatula and Arabidopsis thaliana separately in the same soil. We extracted RNA from the root-adhering soil and the root tissues, and we analysed the bacterial diversity by using 16S rRNA metabarcoding. We measured denitrification activity and denitrification gene expression (nirK and nirS) from each root-adhering soil sample and the root tissues using gas chromatography and quantitative PCR, respectively. We demonstrated that plant species shape denitrification activity and modulate the diversity of the active microbiota through root exudation. We observed a positive effect of T. aestivum and A. thaliana on denitrification activity and nirK gene expression on the root systems. Together, our results underscore the potential power of host plants in controlling microbial activities.

Humankind relies on host–microbe symbioses and the ecosystems they form for diverse services, including food and health. It is important to understand how symbioses will fare in a world facing rapid global change and how adaptation and resilience of symbioses can be aided to secure their services for future generations.

Hydropower dams are back in the spotlight owing to a shifting preference for low carbon energy generation and their possible contribution to mitigating climate change. At the forefront of the renaissance of large hydropower dams are Chinese companies, as the builders of the world's largest dams at home and abroad, opening up opportunities for low- and middle-income countries. However, large hydropower dams, despite their possible developmental and carbon reduction contributions, are accompanied by huge economic costs, profound negative environmental changes and social impacts. Using fieldwork data from four hydropower projects in Ghana, Nigeria, Cambodia and Malaysia, this paper evaluates the behaviour of Chinese stakeholders engaged in large hydropower projects in Asia and Africa. We do this by first exploring the interests of the different Chinese stakeholders and then by investigating the wider implications of these Chinese dams on the local, national and international contexts. The paper concludes that hydropower dams will continue to play a prominent role in future efforts to increase energy security and reduce energy poverty worldwide, therefore the planning, building and mitigation strategies need to be implemented in a more sustainable way that takes into account national development priorities, the needs of local people and the impacts on natural habitats. 水电大坝项目近来因其满足低碳发电和可能减轻气候变化的偏好重回聚光灯下。复兴大型水电项目的主角是作为国内和国外最大大坝建造者的中国企业, 它们在中低收入国家开拓出了许多项目机会。然而大型水电大坝除带来潜在的发展性和减少碳排放的贡献外, 还会伴随着巨大的经济成本、深远的负面环境变化和社会影响。本文利用在加纳、尼日利亚、柬埔寨和马来西亚的四个水电项目中收集到的田野数据将对参与亚非大型水电项目中国利益相关方的行为进行评估。本文将先探明不同中国利益相关方的利益点所在, 然后再对这些中国企业建造的大坝在当地、国家层面和国际层面产生的影响进行探究。本文结论为虽然水电大坝有助于在未来提高能源安全水平和降低能源型贫困, 但项目的规划、建造和缓解策略需要更多以可持续的思路考虑国家层面的发展重点、当地社群的需求及对自然生态的影响。