Widely-tunable mid-infrared ring cavity pump-enhanced OPO and application in photo-thermal interferometric trace ethane detection

Funding: Innovate UK (133076); Engineering and Physical Sciences Research Council (EP//L01596X/1, EP/M01326X/1, EP/M024385/1); European Research Council (ERC-2018-STG 803665).The development of a broadly and accurately tunable single-frequency mid-infrared laser source and its application to a sensitive laser absorption detection method are described. Photo-thermal interferometric spectroscopy is employed as a phase-sensitive method to detect the minute refractive index change caused by the heating of a gas under laser radiation. A separate probe beam allows for the spectrally-interesting mid-infrared region to be examined whilst utilizing low cost, high detectivity photodetectors in the visible/near-infrared region. We also describe the implementation of a Sagnac interferometer to minimize the effects of environmental perturbation and provide inherent passive stability. A continuous-wave ring-cavity pump-enhanced OPO has been developed to provide excitation light from 3–4 µm at 140 mW with the ability to mode-hop tune continuously over 90 cm−1 in 0.07 cm−1 steps. Complementary use of both detection apparatus and excitation source has allowed for presence of ethane to be detected down to 200 parts per billion.developed to provide excitation light from 3–4 µm at 140 mW with the ability to mode-hop tune continuously over 90 cm−1 in 0.07 cm−1 steps. Complementary use of both detection apparatus and excitation source has allowed for presence of ethane to be detected down to 200 parts per billion.Publisher PDFPeer reviewe

Mucedorus: the last ludic playbook, the first stage Arcadia

This article argues that two seemingly contradictory factors contributed to and sustained the success of the anonymous Elizabethan play Mucedorus (c. 1590; pub. 1598). First, that both the initial composition of Mucedorus and its Jacobean revival were driven in part by the popularity of its source, Philip Sidney's Arcadia. Second, the playbook's invitation to amateur playing allowed its romance narrative to be adopted and repurposed by diverse social groups. These two factors combined to create something of a paradox, suggesting that Mucedorus was both open to all yet iconographically connected to an elite author's popular text. This study will argue that Mucedorus pioneered the fashion for “continuations” or adaptations of the famously unfinished Arcadia, and one element of its success in print was its presentation as an affordable and performable version of Sidney's elite work. The Jacobean revival of Mucedorus by the King's Men is thus evidence of a strategy of engagement with the Arcadia designed to please the new Stuart monarchs. This association with the monarchy in part determined the cultural functions of the Arcadia and Mucedorus through the Interregnum to the close of the seventeenth century

Dentists’ training and willingness to treat adolescents with learning disabilities:the mediating role of social and clinical factors

Aim: To test a theoretical model based on Cohen’s dental profession factors (training; practitioner attitudes; geography) to investigate practitioners’willingness to treat adolescents with learning disabilities (LD) in primary dental care. Participants: A sample of all 537 primary care dentists working in a mainly urban area of Northern Ireland and a more rural area of Scotland. Main outcome measure: Willingness to treat adolescents with LD. Method: Questionnaire survey of demographic profile, undergraduate education, current knowledge, attitudes towards individuals with LD and willingness to treat this patient group. A path analytical approach (multiple meditational model) was used. Results: Three hundred dentists participated giving a valid response rate of 61%. Undergraduate education and current knowledge (training) strengthened a social model perspective promoting positive attitudes and willingness to treat adolescents with LD. Undergraduate education and current knowledge about disability did not significantly contribute to dentists whose attitudes were underpinned by the medical model of disability. Therefore geography (rural or urban location) was not an influential factor in willingness to treat adolescents with LD. This does not exclude the possibility that area of work may have an influence as a consequence of undergraduate university attended. Conclusion: This model identifies the importance of undergraduate and continuing dental education with regard to modifying professional attitudes (social and clinical factors) to assist practitioners treat adolescents with LD and provide them with inclusive dental services in primary dental care