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Hydrides based on magnesium and intermetallic compounds provide a viable solution to the challenge of energy storage from renewable sources, thanks to their ability to absorb and desorb hydrogen in a reversible way with a proper tuning of pressure and temperature conditions. Therefore, they are expected to play an important role in the clean energy transition and in the deployment of hydrogen as an efficient energy vector. This review, by experts of Task 40 'Energy Storage and Conversion based on Hydrogen' of the Hydrogen Technology Collaboration Programme of the International Energy Agency, reports on the latest activities of the working group 'Magnesium- and Intermetallic alloys-based Hydrides for Energy Storage'. The following topics are covered by the review: multiscale modelling of hydrides and hydrogen sorption mechanisms; synthesis and processing techniques; catalysts for hydrogen sorption in Mg; Mg-based nanostructures and new compounds; hydrides based on intermetallic TiFe alloys, high entropy alloys, Laves phases, and Pd-containing alloys. Finally, an outlook is presented on current worldwide investments and future research directions for hydrogen-based energy storage.

This study examined the determinants of digitalization and its impact on innovation in Nigeria. The study applied the logit regression and propensity score matching (PSM) on data sourced from the World Bank 2014/2015 enterprise survey. The result from the logit regression shows that size of the firm, educational qualification of the top manager of the firm, business age, employment growth and sector of operation are the major significant determinants of the extent to which firms digitalized in Nigeria. On the other hand, the result from the propensity score matching shows that digitization is positive and significant in explaining the level of firms' innovation in Nigeria. This means that an increased level of ICT will synonymously increase the level of firms' ability to innovate. Based on the results, the study concludes by recommending that managers of various firms should employ a tactical approach to improve on the rate of digitization and innovation to achieve the desired level of productivity.

Process-tracing has grown in popularity among qualitative researchers. However, unlike statistical models and estimators—or even other topics in qualitative methods—process-tracing is largely bereft of guidelines, especially when it comes to teaching. We address this shortcoming by providing a step-by-step checklist for developing a research design to use process-tracing as a valid and substantial tool for hypothesis testing. This practical guide should be of interest for both research application and instructional purposes. An online appendix containing multiple examples facilitates teaching of the method.

Introduktion: Storbritanien er i en omtumlet tid, det politiske landskab har ændret sig radikalt siden 2010, og med Brexit i horizonten, er det svært at male et akkurat billede af offentlighedens og de studerendes mening omkring dette. Dette speciale søger at forstå de Marxistiske Studerende i deres politiske miljø, samt at undersøge, hvordan de interagerer i og mellem deres respektive organisationer. Metode: Den empiriske data indsamlet til dette speciale består af fem interviews med Marxistiske Studerende fra Leeds og Manchester University, og undersøger emnet fra forskellige perspektiver, med udgangspunkt i de forskellige meninger fra de forskellige baggrunde af de studerende og ud fra den marxistiske forståelse. Derudover er data indsamlet fra to forskellige Marxisitiske begivenheder, hvor feltnoter blev nedskrevet, omhandlende de forskellige diskussioner fra begivenhederne. Herudover er 49 rapporter fra Marxist Student Federations hjemmeside blevet anvendt, som en del af det empiriske data. Konklusion: Dette speciale finder at der er manfe ”shadow narratives” eksisterende i Marxist Student Federation, og disse er meget influeret af eksterne aktører, heriblandt Socialist Appeal. Derudover er en svag udnyttelse af ressourcer, når man redegør for tidligere events, hvilket udspiller sig i mange ”shadow narratives” i samfundene., Introduction: The United Kingdom is in a tumultuous time, the political landscape has shifted radically since 2010 and with Brexit on the horizon it is difficult to paint an accurate picture of public, or student sentiment. This thesis seeks to understand Marxist Students in their political environment and to explore how they interact within and between their respective societies.Methods: The empirical data gathered comprises of five interviews with Marxist Society members form Leeds and Manchester Universities which explored the subject from a variety of perspectives representing differing opinions from different backgrounds and of Marxist understanding. Additionally I attended two Marxist events of which field-notes were comprised detailing discussions and complied a collection of 49 reports from the Marxist Student Federation’s website.Conclusion: This thesis finds that many shadow narratives exist within the Marxist Student Federation and are heavily influence by external forces, including Socialist Appeal. Additionally, it is seen that a weak utilisation of sources when reasoning about the past events, displaying many shadow narratives in the societies.

Inclusion criteria: Systematic reviews and randomised controlled trials (RCTs) in English language were included if they fulfilled the following criteria: (a) patients with adhesive capsulitis were included, (b) results on pain and function were reported, and (c) a study period of at least two weeks was reported. Articles were assessed using the Jadad (1) scale and Physiotherapy Evidence Database (PEDro) scale. ‘High-quality’ was defined as a “yes” score of 50% in Jadad scale and a PEDro rating of 5 out of 10. Totally 17 studies were selected for this systematic review.

Recently, there are revolutionary achievements in silicon-based conventional terahertz (THz) and millimeter-wave (mm-wave) integrated circuits, particularly with the advancement of CMOS technology. However, unlike Radio Frequency Integrated Circuits (RFICs), innovative designs and lack of various circuit techniques still remain unknown in THz gap. In this paper, a multi-band THz amplifier is presented in 40 nm CMOS technology with adaptive band selection technique. The smart amplifier is able to adjust the band of operation with respect to input signal power and frequency. In addition, the circuit performance will be adjusted to achieve maximum power gain. In order to achieve multi-band external neutralization, self-healing technique is vastly utilized by means of tunable transmission lines (TTLs). The proposed smart system contains tunable transmission lines, a 5-stage amplifier core, two Successive Approximation Register-based analog-to-digital converters (SAR ADCs), a digital control core and two on-chip power sensing blocks. The fabricated amplifier achieves $P_{1~{\rm dB}}$ of 1 dBm, $P_{sat}$ of 6.1 dBm and power gain of ${\hbox{14.8}}~{\hbox{dB}}\pm { from 197 to 288 GHz frequency range. The proposed amplifier demonstrates the highest operation frequency among all published state-of-arts in all CMOS technologies.

Background To date a variety of teleoperated surgical robotic systems have been developed to improve a surgeon's ability to perform demanding single-port procedures. However typical large systems are bulky, expensive, and afford limited angular motion, while smaller designs suffer complications arising from limited motion range, speed, and force generation. This work was to develop and validate a simple, compact, low cost single site teleoperated laparoendoscopic surgical robotic system, with demonstrated capability to carry out basic surgical procedures. Methods This system builds upon previous work done at the University of Hawaii at Manoa and includes instrument and endoscope manipulators as well as compact articulated instruments designed to overcome single incision geometry complications. A robotic endoscope holder was used for the base, with an added support frame for teleoperated manipulators and instruments fabricated mostly from 3D printed parts. Kinematics and control methods were formulated for the novel manipulator configuration. Results Trajectory following results from an optical motion tracker and sample task performance results are presented. Conclusions Results indicate that the system has successfully met the goal of basic surgical functionality while minimizing physical size, complexity, and cost.

The discoveries of significant resources of oil and gas in the Barnett, Bakken, Marcellus, and other shale formations have presented an opportunity for national petroleum independence and possible export in the relatively near future. These formations are considered to be "unconventional" resources because of the extremely low formation permeability. This means that traditional oil and gas recovery mechanisms are not economical in these formations. With the development of methods for performing multiple hydraulic fractures in horizontally drilled wells in reasonable periods of time economic production of these formations has been seen throughout the world. However, little is known about the optimal spacing of these fractures in horizontal wellbores - how close together should they be to optimize the net present value (balancing costs of drilling, stimulation and production with future revenue). This paper outlines current hydraulic fracturing propagation theory and describes fracture interaction phenomena such as fractures linking-up or one set of fractures inhibiting the growth of others. This leads to insights related to hydraulic fracture spacing. The optimization of hydraulic fracturing spacing was simulated using mShaleTM from Baker Hughes. It was discovered however that the interference of multiple fractures in a defined zone can be modeled with the mShale software package and it serves as a good pseudo design estimation of optimum fracture spacing.

Why is it that some governments recognize only one language while others espouse multilingualism? Related, why are some governments able to shift language policies, and if there is a shift, what explains the direction? In this article, the authors argue that these choices are theproduct of coalitional constraints facing the government during critical junctures in history. During times of political change in the state-building process, the effective threat of an alternate linguistic group determines the emergent language policy. If the threat is low, the government moves toward monolingual policies. As the threat increases, however, the government is forced to co-opt the alternate linguistic group by shifting the policy toward a greater degree of multilingualism. The authors test this argument by examining the language policies for government services and the education system in three Southeast Asian countries (Singapore, Malaysia, and Thailand).

Despite decades of promotion, efforts to encourage participatory irrigation management often falter. Nowhere is this more true that on the island of Java, Indonesia where multiple programmes and millions of dollars have resulted in few effective water user associations. Even so, pockets of participatory success exist. We present findings from one locally developed water user association training programme found in Yogyakarta, Indonesia that has experienced relative success in encouraging farmer participation. We then derive policy lessons from this case. Copyright © 2012 John Wiley & Sons, Ltd.

Vegetable oils have been considered as an alternative to diesel fuel due to their comparable properties and performance. However, the high viscosity of vegetable oil causes engine durability problems with long-term usage. Vegetable oil viscosity can be reduced by blending with diesel fuel in thermodynamically stable mixtures using microemulsion fuel formulation techniques. This work focuses on the formulation of microemulsion fuels comprising diesel fuel and canola oil as the oil phase with ethanol and sec-butanol as viscosity reducers as well as 1-octanol and oleyl amine as surfactant/cosurfactant. Selective tests on an instrumented diesel engine were performed for formulated microemulsion fuels and No. 2 diesel fuel for comparison. The results show that formulated microemulsion fuels have fuel properties that meet the ASTM requirements for viscosity, cloud point, and pour point for biodiesel. Even more important, they have phase stability over a wide range of temperatures (−10 to 70 °C). Although all of the microemulsion fuels showed higher fuel consumption than diesel fuel, some of the microemulsion fuels had significantly reduced CO and NOx emissions as well as reduced particulates when compared to baseline diesel fuel. The research demonstrates the potential of these microemulsion fuels as alternative to neat diesel fuel.

This paper investigates the re-centring of religious identity within the geo-body in the developing world through the case study of Thailand, formerly Siam. Although by 1932, monarchic rule and colonial powers had demarcated the ‘geo-body’ of Siam, the national soul was not yet fully cultivated. After the fall of the absolute monarchy, Prime Minister Phibunsongkhram sought to mould the religio-national identity of Thailand until the religious community's borders coincided with those of the nation-state. One focus of nationalist leaders' efforts was the adaptation and promotion of Buddhist temples throughout the state. These temples became markers of both geographic and cosmological space, serving to infuse the geographic body with a religio-national soul. Thus, the nationalism that developed embraced the fusion of the religious identity with the national identity.

Underground natural gas baseload storage facilities are a vital part of the world's natural gas infrastructure. These facilities allow Exploration & Production (E&P) and transmission pipeline companies to utilize natural gas assets year round while providing means for consistent gas supply throughout the year. The purpose of this thesis is to present a process in which a feasibility study can be conducted for a prospective baseload storage facility. This was accomplished by explaining 1) the theory of natural gas storage reservoir engineering; 2) geologic consideration for underground storage prospects; 3) design of a new underground baseload facility using decline curve analysis and hysteresis analysis; and 4) a detailed economic analysis of a storage prospect. A depleted natural gas reservoir was evaluated for its potential to become an underground baseload storage facility for natural gas. For this underground reservoir, it is estimated the Original Gas in Place (OGIP) was 59.4 Billion Cubic Feet (BCF) using hysteresis analysis. The cushion gas requirement was solved to be 50% of the OGIP, or 29.7 BCF. There is currently 7.4 BCF of native gas present in the reservoir. The required injection cushion gas requirement is estimated at 22.3 BCF. The maximum field deliverability was estimated to be 284.3 Thousand Cubic Feet per Day (MCF/D) at a reservoir pressure of 868.5 psia. The minimum field deliverability was estimated to be 83.8 MCF/D at a cushion gas pressure of 434.1 psia. Maximum and minimum deliverabilities assume 30 injection/withdrawal wells are present at 6 different well pads throughout the field. After analyzing three different economic scenarios for the prospective storage field it was determined this project is not economically feasible under current market conditions. Recommendations for future work include the operating company conducting a 3D seismic survey and re-evaluating the project using 3D reservoir simulation evaluating the possibilities of 1) using horizontal drilling to minimize number of wells, 2) simulate storage well performance if vertical wells are hydraulically fractured, and/or 3) simulate if the prospective storage facility can be pressurized over the original discovery pressure.

We have recently developed a compact, lightweight platform that can be worn on the finger of the user, so that haptic feedback can be generated directly on the fingertip pad rather than through a grasped instrument handle. A planar array of cylindrical coils and a 3D rigid-body motion tracker generate forces and torques on the magnet in the levitated platform worn by the user. This study compares perception of sinusoidal surface roughness across three different renderings: (1) with no torque feedback, (2) with torque feedback to follow the local surface slope, and (3) with torque feedback to prevent the fingertip from roll and pitch rotations. The results show that perceived roughness decreases with wavelength in all three conditions, but in addition, and independently, there are strong effects of torque feedback.

Paddlefish Polyodon spathula, 180–250 mm in total length and reared in concrete raceways, were implanted with 1-mm-long coded wire tags to evaluate short-term (72 h) retention. Retention rates were significantly different (P < 0.01) among implant locations. Mean retention rates were: tip of rostrum, 71%; side of rostrum, 96% : underside of rostrum, 99%.

We consider a reaction diffusion system whit a triangular matrix of diffusion coefficients satisfying a balance law on a bounded domain with no-flux boundary condition. We demonstrate that globally bounded solutions exist for any reaction term provided a condition on the diffusion coefficients is satisfied. The proof makes use of some properties of the Neumann function for the heat equation posed in a bounded domain recently obtained in [12]. When the spatial domain is {\rm \bf R}$^N$, the proof relies on well-known properties of the fundamental solution of the heat equation.

Two chemical solutions, 1.5% sodium sulfite and 1.5% sodium sulfite with 0.2% papain, were compared for their efficacy in separating the glycoprotein matrix of spawns from channel catfish (Ictalurus punctatus). The performance of the solutions was evaluated by comparing the numbers of live fry obtained per kilogram of egg mass. No significant differences in the performance of the solutions were detected, and it was concluded that the use of papain does not appear to be necessary.