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TAE Technologies’ fifth-generation fusion device, C-2W (also called ‘Norman’), is the world’s largest compact-toroid device and has made significant progress in field-reversed configuration (FRC) plasma performance. C-2W produces record breaking, macroscopically stable, high-temperature advanced beam-driven FRC plasmas, dominated by injected fast particles and sustained in steady state, which is primarily limited by neutral-beam (NB) pulse duration. The NB power supply system has recently been upgraded to extend the pulse length from 30 ms to 40 ms, which allows for a longer plasma lifetime and thus better characterization and further enhancement of FRC performance. An active plasma control system is routinely used in C-2W to produce consistent FRC performance as well as for reliable machine operations using magnet coils, edge-biasing electrodes, gas injection and tunable-energy NBs. Google’s machine learning framework for experimental optimization has also been routinely used to enhance plasma performance. Dedicated plasma optimization experimental campaigns, particularly focused on the external magnetic field profile and NB injection (NBI) optimizations, have produced a superior FRC plasma performance; for instance, achieving a total plasma energy of ∼13 kJ, a trapped poloidal magnetic flux of ∼16 mWb (based on the rigid-rotor model) and plasma sustainment in steady state up to ∼40 ms. Furthermore, under some operating conditions, the electron temperature of FRC plasmas at a quiescent phase has successfully reached up to ∼1 keV at the peak inside the FRC separatrix for the first time. The overall FRC performance is well correlated with the NB and edge-biasing systems, where higher total plasma energy is obtained with higher NBI power and applied voltage on biasing electrodes. C-2W operations have now reached a mature level where the machine can produce hot, stable, long-lived, and repeatable plasmas in a well-controlled manner.

Detection of machining-induced white layers is currently a destructive inspection process with a form of cross-sectional microscopy required. This paper, therefore, reports on the development of a novel non-destructive inspection method for detecting white layers using grain size-sensitive and crystallographic texture-sensitive techniques. It is shown that x-ray diffraction can be used to detect white layers as thin as 5 μm in Ti-6Al-4 V through measurement of diffraction peak breadths and diffraction peak intensities, due to the influence of the sub 100 nm grain size and high lattice strain in the white layer, as well as the strong crystallographic texture in this titanium alloy. Compared to the existing optical microscopy inspection method, which can take days due to the number of steps involved, the x-ray diffraction peak breadth method offers non-destructive white layer detection in a matter of minutes at a resolution of 5 μm or less that competes directly with the optical method. Spatially resolved acoustic spectroscopy, a laser-generated ultrasonic surface acoustic wave detection method, can also be used to identify anomalous surfaces, containing a white layer or swept grain material, due to its sensitivity to the crystallographic texture changes that arise in severely plastically deformed Ti-6Al-4V as in Titanium with 6 % Aluminium and 4% Vanadium.

The paper evaluates the significance of existing and potential future conflicts between the United States and Western Europe on matters of trade and tariff policy, and suggests ways in which these conflicts might possible be resolved. The evolution of trade policy since the 1930s and its current status as codified and implemented by means of the General Agreement on Tariffs and Trade is first briefly reviewed. Some facts regarding the commodity structure and geographic distribution of the trade of the U.S. and Western Europe and the import duties and other restrictions used by these regions to protect domestic producers are then provided. The issues, outcome, and unresolved problems of the Kennedy Round of GATT tariff negotiations that was concluded in mid-1967 are then discussed, before a number of issues that were on the whole bypassed during the Kennedy Round and that are potentially disruptive to trade relations are examined. Various alternative methods by which further trade liberalisation can be pursued are then considered. Finally, future foreign trade policy for the U.S. and Western Europe are considered. JEL: F13

The question of determining how many doses may be skipped before HIV treatment response is adversely affected by the emergence of drug-resistance is addressed. Impulsive differential equations are used to develop a prescription to minimize the emergence of drug-resistance for protease-sparing regimens. A threshold for the maximal number of missable doses is determined. If the number of missed doses is below this threshold, then resistance levels are negligible and dissipate quickly, assuming perfect adherence subsequently. If the number of missed doses exceeds this threshold, even for 24h, resistance levels are extremely high and will not dissipate for weeks, even assuming perfect adherence subsequently. After this interruption, the minimum number of successive doses that should be taken is determined. Estimates are provided for all protease-sparing drugs approved by the US Food and Drug Administration. Estimates for the basic reproductive ratios for the wild-type and mutant strains of the virus are also calculated, for a long-term average fractional degree of adherence. There are regions within this fraction of adherence where the outcome is not predictable and may depend on a patient's entire history of drug-taking. [ABSTRACT FROM AUTHOR]

With over 1.7 billion individuals engaged in social media, patients and consumers share more about their lives than ever before through wearable devices, smartphone applications, and social media outlets. This cornucopia of data offers significant opportunity for health researchers and clinicians to track and explore how digital presence contributes to patients' health outcomes and use of health care resources. While patients readily share their information with online communities, it is imperative that they maintain a sense of autonomy over who has access to such data. Recent data breaches of major insurance companies and retailers illustrate the challenges and vulnerabilities related to information safety and privacy. Many Web sites and mobile apps require users to agree to data policies, but how those data are mined, protected, used, and externally shared is frequently nontransparent, resulting in a climate of fear and distrust around all forums of digital information sharing. Although such skepticism is perhaps justified, it should not deter health researchers from attempting to collect and analyze these novel data for the purpose of designing unique health interventions. By clarifying intent around digital data acquisition, simplifying consent procedures, and affirming a commitment to privacy, the authors contend that health researchers can partner with patients to transform the boundaries of scientific inquiry.