Pathway to clozapine use:a comparison between a patient cohort from New Zealand and a cohort from the United Kingdom

Background and Objective: Clozapine has been available since the early 1990s. Studies continue to demonstrate its superior efficacy in treatment-resistant schizophrenia. Despite this, numerous studies show under-utilisation, delayed access and reluctance by psychiatrists to prescribe clozapine. This retrospective cross-sectional study compared the prescribing of clozapine in two adult cohorts under the care of large public mental health services in Auckland (New Zealand) and Birmingham (United Kingdom) on 31 March 2007. Method: Time from first presentation to clozapine initiation, prior antipsychotics trialled and antipsychotic co-prescribing were compared. Data included demographics, psychiatric diagnosis, co-morbid conditions, year of first presentation, admissions and pharmacological treatment (clozapine dose, start date, prior antipsychotics, co-prescribed antipsychotic). Results: Overall, 664 people were prescribed clozapine (402 Auckland; 262 Birmingham); mean daily dose of 384 mg (Auckland) and 429 mg (Birmingham). 53 % presented after 1990 and the average duration of time before starting clozapine was significantly longer in the Birmingham cohort (6.5 vs. 5.3 years) but this reduced in both cohorts to a 1-year mean in those presenting within the last 3 years. The average number of antipsychotics trialled pre-clozapine for those presenting since 1990 was significantly higher in the Birmingham cohort (4.3 vs. 3.1) but in both cohorts this similarly reduced in those presenting within the last 3 years. Antipsychotic co-prescribing was significantly higher in the Birmingham cohort (22.9 vs. 10.7 %). Conclusions: There is evidence that access to clozapine has improved over time in both cohorts, with a reduction in the duration between presentation and initiation of clozapine and number of different antipsychotics trialled pre-clozapine. These are very positive findings in terms of optimising outcomes with clozapine and are possibly due to the impact of guideline recommendations, increasing clinician, consumer and carer knowledge, and experience with clozapine and funding changes. © 2014 Springer International Publishing.

Long-range and high-resolution correlation optical time-domain reflectometry utilizing an all optical chaotic source

A high resolution optical time domain reflectometry (OTDR) based on an all-fiber chaotic source is demonstrated. We analyze the key factors limiting the operational range of such an OTDR, e.g., integral Rayleigh backscattering and the fiber loss, which degrade the optical signal to noise ratio at the receiver side, and then the guideline for counter-act such signal fading is discussed. The experimentally demonstrated correlation OTDR presents ability of 100km sensing range and 8.2cm spatial resolution (1.2 million resolved points), as a verification of the theoretical analysis. To the best of our knowledge, this is the first time that correlation OTDR measurement is performed over such a long distance with such high precision.

Wireless power and data transfer via a common inductive link using frequency division multiplexing

For wireless power transfer (WPT) systems, communication between the primary side and the pickup side is a challenge because of the large air gap and magnetic interferences. A novel method, which integrates bidirectional data communication into a high-power WPT system, is proposed in this paper. The power and data transfer share the same inductive link between coreless coils. Power/data frequency division multiplexing technique is applied, and the power and data are transmitted by employing different frequency carriers and controlled independently. The circuit model of the multiband system is provided to analyze the transmission gain of the communication channel, as well as the power delivery performance. The crosstalk interference between two carriers is discussed. In addition, the signal-to-noise ratios of the channels are also estimated, which gives a guideline for the design of mod/demod circuits. Finally, a 500-W WPT prototype has been built to demonstrate the effectiveness of the proposed WPT system.

Long-range and high-precision correlation optical time-domain reflectometry utilizing an all-fiber chaotic source

We propose a long range, high precision optical time domain reflectometry (OTDR) based on an all-fiber supercontinuum source. The source simply consists of a CW pump laser with moderate power and a section of fiber, which has a zero dispersion wavelength near the laser's central wavelength. Spectrum and time domain properties of the source are investigated, showing that the source has great capability in nonlinear optics, such as correlation OTDR due to its ultra-wide-band chaotic behavior, and mm-scale spatial resolution is demonstrated. Then we analyze the key factors limiting the operational range of such an OTDR, e. g., integral Rayleigh backscattering and the fiber loss, which degrades the optical signal to noise ratio at the receiver side, and then the guideline for counter-act such signal fading is discussed. Finally, we experimentally demonstrate a correlation OTDR with 100km sensing range and 8.2cm spatial resolution (1.2 million resolved points), as a verification of theoretical analysis.

The experiences of con sultations on oral anticoagula-tion for AF:the importance of qualitative research incardiovascular sciences

Objectives: Multiple-perspective qualitative designs can aid researchersto develop a more multifaceted account of a phenomenon and as aform of triangulation of data. Two interlinking studies aimed toexplore patients’ and physicians’ experiences of atrial fibrillation (AF)and warfarin.Methods: Audio-recorded semistructured individual interviews wereused. Study 1: Three AF patient subgroups were interviewed (n = 11);accepted, refused, or discontinued warfarin. Study 2: Four physiciansubgroups (n = 16): consultant cardiologists, consultant general physi-cians, general practitioners, and cardiology registrars. Data was ana-lyzed using interpretative phenomenological analysis, a qualitativemethodology.Results: Study 1: Three overarching themes comprised patients’ experi-ences: the initial consultation, life after the consultation, and patients’reflections. Patients commented on the reassurance experienced duringthe consultation, but they perceived the decision-making processmostly led by the physician. Lack of education and take-home materi-als during the initial consultation were highlighted. Patients’ uptake ofinformation was influenced by past experiences and knowledge ofstroke and/or bleeding. Study 2: Two overarching themes covered phy-sicians’ experiences: communicating information and challenges withwarfarin prescription for AF. Physicians’ approach to the consultationstyle shifted through a continuum of compliance-adherence-concor-dance during the consultation. Time and the perceived patient trust inthem as the expert led to physicians to adopt a paternalistic approach.Guideline adherence and the need to adopt a multidisciplinaryapproach were pointed out as current challenges.Conclusion: There is a need to target patients’ and physicians’ abilityto communicate with each other in a comprehensible way. This projecthas illustrated the benefit of using a qualitative approach to under-stand the lived experience of the physician–patient consultation.Disclosure of Interest: None declare

Safety criteria for the private spaceflight industry

The Federal Aviation Administration (FAA) Office of Commercial Space Transportation (AST) has set specific rules and generic guidelines to cover experimental and operational flights by industry forerunners such as Virgin Galactic and XCOR. One such guideline Advisory Circular (AC) 437.55-1[1] contains exemplar hazard analyses for spacecraft designers and operators to follow under an experimental permit. The FAA's rules and guidelines have also been ratified in a report to the United States Congress, Analysis of Human Space Flight Safety[2] which cites that the industry is too immature and has 'insufficient data' to be proscriptive and that 'defining a minimum set of criteria for human spaceflight service providers is potentially problematic' in order not to 'stifle the emerging industry'. The authors of this paper acknowledge the immaturity of the industry and discuss the problematic issues that Design Organisations and Operators now face.