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Detailed studies of intense light – material interactions has led to new insights into fs laser induced refractive index change in a range of glass types. This body of knowledge enables the development of advanced processing methodologies, resulting in novel planar and 3D guided wave devices. We will review the chemistry and morphology associated with fs laser induced refractive index change in multi-component glasses such as ZBLAN, phosphates and silicates, and discuss how these material changes inform our research programs developing a range of active and passive lightwave systems.

Examines the risks in the use of balloon dilatation of the aortic valve in patients with calcific aortic stenosis. Complications of the procedure; Survival of the patients following dilatation; Advice on the application of balloon dilatation of the aortic valve.

Coronary artery fistulae (CAF) are rare anomalies. They are vascular communications between the coronary arteries and other cardiac structures, either cardiac chambers or great vessels. There can be considerable variation in the course of a coronary artery fistula. We report a case of a coronary artery fistula between the left circumflex coronary artery and the right and left atria. CAF are often diagnosed by coronary angiogram, however with the advent of new technologies such as Coronary Computed Tomography Angiography (Coronary CTA) the course and communications of these fistulae can be delineated non-invasively and with greater accuracy. [ABSTRACT FROM AUTHOR]

Presents a case of diplopia following intravenous administration of pamidronate in Great Britain. Function of pamidronate or aminobiphosphonate; Complications of intravenous disodium pamidronate administration for the treatment of osteolytic lesions secondary to multiple myeloma; Etiology of diplopia.

Abstract Coronary artery fistulae (CAF) are rare anomalies. They are vascular communications between the coronary arteries and other cardiac structures, either cardiac chambers or great vessels. There can be considerable variation in the course of a coronary artery fistula. We report a case of a coronary artery fistula between the left circumflex coronary artery and the right and left atria. CAF are often diagnosed by coronary angiogram, however with the advent of new technologies such as Coronary Computed Tomography Angiography (Coronary CTA) the course and communications of these fistulae can be delineated non-invasively and with greater accuracy.

Multiple national and international trends and drivers are radically changing what biological security means for the United Kingdom (UK). New technologies present novel opportunities and challenges, and globalisation has created new pathways and increased the speed, volume and routes by which organisms can spread. The UK Biological Security Strategy (2018) acknowledges the importance of research on biological security in the UK. Given the breadth of potential research, a targeted agenda identifying the questions most critical to effective and coordinated progress in different disciplines of biological security is required. We used expert elicitation to generate 80 policy-relevant research questions considered by participants to have the greatest impact on UK biological security. Drawing on a collaboratively-developed set of 450 questions, proposed by 41 experts from academia, industry and the UK government (consulting 168 additional experts) we subdivided the final 80 questions into six categories: bioengineering; communication and behaviour; disease threats (including pandemics); governance and policy; invasive alien species; and securing biological materials and securing against misuse. Initially, the questions were ranked through a voting process and then reduced and refined to 80 during a one-day workshop with 35 participants from a variety of disciplines. Consistently emerging themes included: the nature of current and potential biological security threats, the efficacy of existing management actions, and the most appropriate future options. The resulting questions offer a research agenda for biological security in the UK that can assist the targeting of research resources and inform the implementation of the UK Biological Security Strategy. These questions include research that could aid with the mitigation of Covid-19, and preparation for the next pandemic. We hope that our structured and rigorous approach to creating a biological security research agenda will be replicated in other countries and regions. The world, not just the UK, is in need of a thoughtful approach to directing biological security research to tackle the emerging issues., Competing Interests: Authors TM and HS are affiliated with Opencell. KM is affiliated with Biosecure Ltd. Arcadia provided support in the form of salaries for authors WS and CR. There are no patents, products in development or marketed products to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Beyond the use of genuine monolithic integrated optical platforms, we report here a hybrid strategy enabling on-chip generation of configurable heralded two-photon states. More specifically, we combine two different fabrication techniques, i.e., non-linear waveguides on lithium niobate for efficient photon-pair generation and femtosecond-laser-direct-written waveguides on glass for photon manipulation. Through real-time device manipulation capabilities, a variety of path-coded heralded two-photon states can be produced, ranging from product to entangled states. Those states are engineered with high levels of purity, assessed by fidelities of 99.5 ± 8% and 95.0 ± 8%, respectively, obtained via quantum interferometric measurements. Our strategy therefore stands as a milestone for further exploiting entanglement-based protocols, relying on engineered quantum states, and enabled by scalable and compatible photonic circuits.

Scaling up linear-optics quantum computing will require multi-photon gates which are compact, phase-stable, exhibit excellent quantum interference, and have success heralded by the detection of ancillary photons. We investigate the design, fabrication and characterisation of the optimal known gate scheme which meets these requirements: the Knill controlled-Z gate, implemented in integrated laser-written waveguide arrays. We show device performance to be less sensitive to phase variations in the circuit than to small deviations in the coupler reflectivity, which are expected given the tolerance values of the fabrication method. The mode fidelity is also shown to be less sensitive to reflectivity and phase errors than the process fidelity. Our best device achieves a fidelity of 0.931 ± 0.001 with the ideal 4 × 4 unitary circuit and a process fidelity of 0.680 ± 0.005 with the ideal computational-basis process.

The generation of coherent and indistinguishable single photons is a critical step for photonic quantum technologies in information processing and metrology. A promising system is the resonant optical excitation of solid-state emitters embedded in wavelength-scale three-dimensional cavities. However, the challenge here is to reject the unwanted excitation to a level below the quantum signal. We demonstrate this using coherent photon scattering from a quantum dot in a micropillar. The cavity is shown to enhance the fraction of light that is resonantly scattered toward unity, generating antibunched indistinguishable photons that are 16 times narrower than the time-bandwidth limit, even when the transition is near saturation. Finally, deterministic excitation is used to create two-photon N00N states with which we make superresolving phase measurements in a photonic circuit.

Integrated photonics promises solutions to questions of stability, complexity, and size in quantum optics. Advances in tunable and non-planar integrated platforms, such as laser-inscribed photonics, continue to bring the realisation of quantum advantages in computation and metrology ever closer, perhaps most easily seen in multi-path interferometry. Here we demonstrate control of two-photon interference in a chip-scale 3D multi-path interferometer, showing a reduced periodicity and enhanced visibility compared to single photon measurements. Observed non-classical visibilities are widely tunable, and explained well by theoretical predictions based on classical measurements. With these predictions we extract Fisher information approaching a theoretical maximum. Our results open a path to quantum enhanced phase measurements.

We demonstrate three and four input multiports in a three dimensional glass platform, fabricated using the femtosecond laser direct-write technique. Hong-Ou-Mandel (HOM) interference is observed and a full quantum characterization is performed, obtaining two photon correlation matrices for all combinations of input and output ports. For the 3-port case, the quantum visibilities are accurately predicted solely from measurement of the classical coupling ratios.

Objectives: The purpose of this study was to describe the results of transluminal extraction coronary atherectomy in native coronary arteries., Background: Transluminal extraction coronary atherectomy was approved by the Food and Drug Administration for use in native coronary arteries and vein grafts., Methods: Between December 1988 and July 1992, transluminal extraction coronary atherectomy was performed in 181 native coronary arteries in 175 patients. A detailed angiographic and clinical assessment was performed., Results: Quantitative angiography (mean +/- SD) revealed an increase in minimal lumen diameter from 1.0 +/- 0.6 mm before to 1.3 +/- 0.7 mm after atherectomy, to 2.1 +/- 0.8 mm after final treatment (p < 0.001), corresponding to a diameter stenosis of 70 +/- 16%, 61 +/- 21% and 36 +/- 21%, respectively (p < 0.001). Final procedural success (final diameter stenosis < 50%, no major complications) was achieved in 84%. Adjunctive angioplasty was used after atherectomy in 152 lesions (84%) to further enlarge lumen dimensions (130 lesions, 72%), salvage technical failures (2 lesions, 1%) and reverse atherectomy-induced abrupt closures (20 lesions, 11%). Clinical complications included death (2.3%), Q wave myocardial infarction (3.4%) and emergency bypass surgery (2.8%). The strongest independent correlate of major clinical complications was development of abrupt closure immediately after atherectomy (p = 0.01). Clinical follow-up of 92% of eligible patients revealed clinical restenosis (repeat intervention, late bypass surgery, myocardial infarction or death) in 28.5%. Angiographic follow-up of 83% of eligible lesions revealed a restenosis rate (diameter stenosis > 50%) of 61%., Conclusions: Transluminal extraction coronary atherectomy is limited by a modest degree of lumen enlargement, frequent need for adjunctive angioplasty and a high restenosis rate. For complex lesions in native coronary arteries, transluminal extraction coronary atherectomy appears to offer no advantage over conventional balloon angioplasty.

To evaluate the efficacy, safety, and long-term results of atherectomy using the Transluminal Extraction catheter (TEC), patients with diseased saphenous vein grafts were enrolled in a prospective nonrandomized trial. Patients were followed to hospital discharge for acute complications and underwent routine 6-mo reevaluation with repeat cardiac catheterization to assess restenosis. Atherectomy was performed on 650 graft lesions in 538 consecutive patients (male 81%; mean age 66 yr; range 37-81). Mean graft age was 8.3 yr; (range 0.3-20) with 85% of grafts > 3 yr of age. Complex lesion morphology included thrombus (28%), ulceration (13%), and eccentricity (50%). Lesion success was achieved in 606 lesions (93%) with clinical success in 479 patients (89%). Lesion success was achieved in 90% of thrombus containing lesions, 97% of ulcerated lesions, and 97% of grafts > 3 yr. Complications included nonfatal myocardial infarction in 4 (0.7%) of patients, emergency bypass surgery in 2 (0.41%), and in-hospital death in 17 patients (3.2%). Angiographic follow-up at 6 mo was obtained from 268 lesions in 227 patients. The overall lesion angiographic restenosis rate was 60%. TEC atherectomy can be performed in patients with diseased saphenous vein grafts with high primary success and low complication rates. It is suitable for use in aged grafts, particularly in the presence of thrombus and ulcerations, and may be superior to balloon angioplasty alone in this group of patients.

In a double-blind parallel group study, 46 patients with chronic stable angina were randomized, after a 2-week placebo washout period, to 1 of 3 treatment groups for an additional 2 weeks. Groups 1 and 2 received nicorandil (5 mg, n = 5; 10 mg, n = 10) twice daily, respectively, increasing to 10 and 20 mg (n = 20) twice daily after 1 week of treatment; group 3 continued to receive placebo. A symptom-limited Bruce protocol exercise test was performed before and 2 hours after the initial dose and, after 2 weeks of treatment, 2 and 12 hours after administration. The following parameters were measured: resting, peak exercise and recovery blood pressure and heart rate, exercise duration, time to onset of angina and time to 1 mm of ST-segment depression. After initial dosing, there were significant increases in exercise duration (16%--n = 5, n = 10 vs -2% [placebo]) and time to onset of angina (20%, n = 5; 26%, n = 10 vs 5% [placebo]) (p less than 0.05). Time to onset of 1 mm of ST-segment depression increased in the nicorandil-treated groups compared with that in the placebo group (27%, n = 5; 25%, n = 10 vs 8% [placebo]). Calculated total exercise work increased in both nicorandil groups compared with exercise work in the placebo group (30%, n = 5; 19%, n = 10 vs 3% [placebo]). A decrease in resting systolic blood pressure (12%) in the 10-mg group was the only significant alteration in the hemodynamic parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

The place of balloon dilatation of the aortic valve in the treatment of calcific aortic stenosis is controversial. Thirty two patients (mean age 76) in whom valve replacement was contraindicated were followed up for three to 24 months (mean 8); 25 were in functional class III or IV according to the New York Heart Association's classification. Major complications of the procedure occurred in four patients. Echocardiography and Doppler studies were performed before operation and before discharge in 28 patients, and the area of the valve was measured again six to 50 (mean 23) weeks after operation in 11 patients. The peak to peak aortic pressure gradient fell from a mean of 65 (SD 24) to 46 (20) mm Hg, but the area of the aortic valve, measured by Doppler echocardiography, in 18 patients showed a modest but significant increase, from 0.61 (0.16) to 0.74 (0.23) cm2. One month after dilatation, 29 patients were alive, of whom 17 had improved symptoms. Only two had lasting clinical benefit. Sixteen patients died, 12 of a cardiac cause. The estimated one year survival rate was 49%. Six patients underwent or required valve replacement because of persisting symptoms. In view of its limited long term efficacy balloon dilatation of the aortic valve should be used only for patients with severe symptoms whose life expectancy is limited by other disease or who are considered to be unsuitable for valve replacement. It may have a role in improving the condition of patients who present with cardiogenic shock or pulmonary oedema before valve replacement is undertaken.

Computed tomography (CT) has proven useful in diagnosing inflammatory and neoplastic disease of the pancreas. Neoplasms of the pancreas produce enlargement of the gland and loss of surrounding fat planes. Acute pancreatitis also produces enlargement but correct diagnosis can be made with the clinical correlation. The usefulness of CT in chronic pancreatitis depends upon the state of the disease. Distinction between an inflammatory and a neoplastic mass is not possible on the basis of a CT scan alone. CT is also useful for needle guidance for aspiration biopsy of the pancreas.

Spatial resolution of the EMI and Delta computed tomographic scanners has been measured by recording the response to a nylon and water sunburst phantom (Siemens star) and calculating the modulation transfer function at radii corresponding to various spatial frequencies. The resolution appears to be related primarily to the size of the matrix element, and exhibits an upper cut-off frequency somewhat in excess of 3 cycles/cm.