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Pressure sensors based on fiber Bragg gratings in side-hole optical fiber enable remote monitoring of pressure at multiple points within many otherwise inaccessible environments. However, sensors fabricated from side-hole fiber drawn from a preform have limitations in their design and material composition. The design of such sensors is a compromise between achieving good sensitivity, while also minimizing splice losses due to mode-mismatch. We have developed optimized designs for pressure sensors with complex 3D structures using simulations and fabricated them within commercial step-index fibers. The fabrication uses a femtosecond laser in conjunction with selective etching to write precisely defined voids within the fiber cladding. The sensors were tested in a hydraulic system up to 600 bar and achieved a sensitivity of 0.41 pm/bar. The technique has potential for enabling pressure sensors in many types of high-performance fibers for a range of sensing applications.

Sapphire fiber can withstand temperatures of around 2000 °C, but it is multimoded, giving poor precision sensors. We have demonstrated a single-mode sapphire fiber Bragg grating temperature sensor operating up to 1200 °C. A single-mode sapphire fiber was formed by writing a depressed cladding waveguide along the length of a 100-μm diameter sapphire fiber using a femtosecond laser. A second-order Bragg grating sensor was inscribed within the waveguide, achieving a reflectivity of >90% and a narrow bandwidth of <0.5 nm. The single-mode sapphire fiber was fusion spliced to standard silica single-mode fiber. The sensor was vibration-tested over a 10 Hz to 30 kHz range with 30 μm displacement, resulting in minimal Bragg wavelength variation of <30 pm standard deviation. The sensor was furnace-tested to 1200 °C, showing ±0.08% repeatability above 1000 °C. This demonstrates the high precision sensing capability of single-mode sapphire fiber Bragg grating sensors with end-to-end single mode interrogation.

We demonstrate the fabrication and optimization of waveguide Bragg gratings on single-crystal sapphire substrates using femtosecond laser direct writing. The gratings are fabricated using modulated bursts and are embedded inside single-mode depressed cladding waveguides. Through design optimization, and fabrication parameter tuning, a depressed cladding waveguide with a loss of ∼0.8 dB/cm and a Bragg grating with a reflectivity of higher than 90% in the telecommunications wavelength band are demonstrated. The waveguide Bragg grating exhibits stable thermal properties under annealing at 1200 °C. A sampled grating and a grating array are also demonstrated, showing the potential for more complex grating designs.

Although Strombomonas verrucosahas been the type of the genus name for almost 100 years, its lack of clear diagnostic traits has rendered morphological distinction from its congeners almost impossible. As such, a study was conducted combining previously unused morphological data (chloroplast characters) with molecular data (sequences of nuclear SSU, LSU and plastid‐encoded SSU rDNA) and extensive literature review. The study focused on environmental samples obtained from Poland and China and resulted in 51 new sequences representing three molecular markers (17 nSSU, 16 nLSU and 18 cpSSU rDNA). Revised delimitations of the genus Strombomonasand its type S. verrucosaare presented that include new and detailed diagnostic characters. In addition to the type, we recognize nine species: S. acuminata, S. borystheniensis, S. eurystoma, S. fluviatilis, S. gibberosa, S. maxima, S. ovalis, S. schauinslandii, S. triquetra. Three of these are incorporated into a phylogeny for the first time (S. fluviatilis, S. gibberosa, S. schauinslandii). To improve the efficiency of DNA isolation from loricate cells, a protocol utilising a chelating resin for DNA isolation – following the lead of diatomologists – has been adjusted for Euglenaceae and is also presented.

Opportunities for refugees to engage in occupations within host countries can be constrained by factors such as governmental policies or language barriers (Smith). Female refugees with physical disabilities may experience compounding barriers to participation related to their identity markers. The main aim of this study is to understand the experiences of female refugees with physical disabilities in seeking, preparing for, and obtaining employment. This study used an instrumental case study using semistructured interviews with five primary participants and four caregivers. Thematic analysis (Clarke & Braun) identified five key barriers to securing employment: (a) stigma and discrimination, (b) restrictive traditional labor market, (c) inaccessible and inadequate housing, (d) lack of cohesion and information across services, and (e) English language predominance. Findings highlight complex challenges experienced by the women who faced intersecting systems of oppression and can enable occupational therapists to address barriers associated with occupational injustice by improving services to better meet their needs.

We present fiber Bragg gratings (FBGs) fabricated using adaptive optics aberration compensation for the first time to the best of our knowledge. The FBGs are fabricated with a femtosecond laser by the point-by-point method using an air-based objective lens, removing the requirement for immersion oil or ferrules. We demonstrate a general phase correction strategy that can be used for accurate fabrication at any point in the fiber cross-section. We also demonstrate a beam-shaping approach that nullifies the aberration when focused inside a central fiber core. Both strategies give results which are in excellent agreement with coupled-mode theory. An extremely low wavelength polarization sensitivity of 4 pm is reported.

We present a flexoelectro-optic liquid crystal (LC) analog phase modulator with >2π phase range at a 1 kHz switching frequency. The chiral nematic LC mixture consists of the bimesogen CBC7CB with chiral dopant R5011, aligned in the uniform lying helix mode. The mixture exhibits >±π/4 rotation of the optic axis for a drive voltage of ±21.5  V (E=±4.5  V μm^−1). The rotation of the optic axis is converted into a phase modulation with the aid of a reflective device configuration incorporating a ∼5  μm LC cell, a polarizer, two quarter-wave plates, and a mirror. The residual amplitude modulation is found to be <23%. This flexoelectro-optic phase modulator combination has the potential to enable analog spatial light modulators with very fast frame rates suitable for a range of applications.

Negotiators are routinely exhorted to prepare well, but what do they do in practice? This article draws on data collected as a team of negotiators prepared their strategy during the lengthy negotiations over a major power generation infrastructure contract. Using a framework that we developed using terms from the literature, the team’s preparation meetings were observed and then analysed for content, timing and changes in participation.It is shown that the standard checklist notion of preparation needs to be reconsidered as a multilevel, dynamic concept that changes in character over time. Far from just a first stage, the team’s continued preparation occurred in feedback meetings after rounds of negotiation at the table, between negotiation sessions and immediately before the next round of negotiations, and progress was seen to hinge on the differentiation of the preparation. Consequently, this long-term study provides insight into a key element of any general theory of negotiation while also suggesting implications for practitioners working with negotiating teams.

This article focuses on the negotiation of buyer–supplier relationships and the associated activities that are required to maintain them. After analysing and distilling contributions from the literature, we developed a 10-item questionnaire that was subsequently used as a guide for interviewing 36 practitioners in the field. These responses provided new insights into the attitudes and actions that contribute to relationship management success from a negotiations perspective. This led to the development of a framework that encapsulates key considerations for negotiation and relationship management specifically from a procurement process perspective.

ABSTRACTThe adoption of a statutory national minimum wage policy in the UK is proving ineffective in resolving the problem of low pay. The emergence of living wage campaigns in the UK follows similar developments in the USA, and more recently, New Zealand. Rather than focus on a particular employer-specific campaign, this paper explores the campaign of the General and Municipal Boilermakers Union (GMB) in local government which recruits members from low-paid occupations. The 11 local government sector cases examine contracted workers allied to local government services, drawing on interviews with full-time officers, lay representatives and members involved in the campaigns. Nine campaigns were successful and two were not. The Union’s strategy revealed an interplay between industrial and political influences and, despite the social-economic nature of the issue, the limited extent of involvement of social movements in the campaign.