Risk indictors in cats with preclinical hypertrophic cardiomyopathy: a prospective cohort study

Objectives This study aimed to identify indicators of the risk of progression of preclinical hypertrophic cardiomyopathy (HCM). Methods This was a prospective cohort study following a population of cats with preclinical HCM. Cats serially underwent physical examination, blood pressure measurement, blood sampling and echocardiography. Development of congestive heart failure (CHF), arterial thromboembolism (ATE) or sudden death (SD) were considered cardiac-related events. Associations between factors recorded at baseline, and on revisit examinations, and the development of a cardiac-related event were explored using receiver operator characteristic (ROC) analysis. Results Forty-seven cats were recruited to the study and were followed for a median period of 1135 days. Fifteen cats (31.9%) experienced at least one cardiac-related event; six CHF, five ATE and five SD. One cat experienced a cardiac-related event per 10.3 years of patient follow-up. Cats with increased left atrial (LA) size and higher concentrations of N-terminal pro B-type natriuretic peptide (NTproBNP) at baseline were more likely to experience an event. Cats with a greater rate of enlargement of LA size between examinations were also more likely to experience an event. Conclusions and relevance Factors easily measured, either once or serially, in cats with preclinical HCM can help to identify those at greater risk of going on to develop clinical signs

Time-Domain All-Optical Demultiplexing With A Semiconductor Directional Coupler

We report the demonstration of demultiplexing of 150 fs pulses, without pulse breakup, in an AlGaAs nonlinear directional coupler operated at photon energies below half the band gap energy of AlGaAs

Globalisation, neo-liberalism and vocational learning: the case of English further education colleges

Further education (FE) has traditionally been a rather unspectacular activity. Lacking the visibility of schools or the prestige of universities, for the vast majority of its existence FE has had a relatively low profile on the margins of English education. Over recent years this situation has altered significantly and further education has undergone profound change. This paper argues that a combination of related factors – neo-liberalism, globalisation, and dominant discourses of the knowledge economy – has acted in synergy to transform FE into a highly performative and marketised sector. Against this backdrop, further education has been assigned a particular role based upon certain narrow and instrumental understandings of skill, employment and economic competitiveness. The paper argues that, although it has always been predominantly working class in nature, FE is now, more than ever, positioned firmly at the lower end of the institutional hierarchy in the highly class-stratified terrain of English education

Challenging the orthodoxy: union learning representatives as organic intellectuals

Teacher education and continuing professional development have become a key areas of controversy in England since the period of school sector restructuring following the 1988 Education Reform Act. More recently teacher training and professional development have often been used to promote and reinforce a narrow focus on the government’s ‘standards agenda’. However, the emerging discourse of ‘new professionalism’ has raised the profile of professional development in schools, and together with union learning representatives, there are opportunities to secure real improvements in teachers’ access to continuing professional development. This paper argues however that union learning representatives must go beyond advocating for better access to professional development and should raise more fundamental questions about the nature of professional development and the education system it serves. Drawing on Gramsci’s notion of the ‘organic intellectual’, the paper argues that union learning representatives have a key role as organisers of ideas – creating spaces in which the ideological dominance of current policy orthodoxy might be challenged

Ultrafast All-Optical Switching In Semiconductor Nonlinear Directional-Couplers At Half The Band-Gap

Efficient ultrafast all-optical switching in nonlinear directional couplers made of AlGaAs and AlGaAs/GaAs quantum wells near half the band gap is reported. The switching is limited by multiphoton absorption which is dominated by three-photon absorption in this spectral range. The three-photon absorption in the quantum well nonlinear directional coupler is stronger than that of bulk AlGaAs. Autocorrelations of the output pulses in the bar and cross states confirm pulse breakup through nonlinear coupling, and illustrate the effects of multiphoton absorption. All sets of experimental data are fitted well by a theoretical model

Optical modulation in a resonant tunneling relaxation oscillator

We report high-speed optical modulation in a resonant tunneling relaxation oscillator consisting of a resonant tunneling diode (RTD) integrated with a unipolar optical waveguide and incorporated in a package with a coplanar waveguide transmission line. When appropriately biased, the RTD can provide wide-bandwidth electrical gain. For wavelengths near the material band edge, small changes of the applied voltage give rise to large, high-speed electroabsorption modulation of the light. We have observed optical modulation at frequencies up to 14 GHz, associated with subharmonic injection locking of the RTD oscillation at the fundamental mode of the coplanar transmission line, as well as generation of 33 ps optical pulses due to relaxation oscillation

Optical modulation at around 1550 nm in an InGaAlAs optical waveguide containing an InGaAs/AlAs resonant tunneling diode

We report electroabsorption modulation of light at around 1550 nm in a unipolar InGaAlAs optical waveguide containing an InGaAs/AlAs double-barrier resonant tunneling diode ~RTD!. The RTD peak-to-valley transition increases the electric field across the waveguide, which shifts the core material absorption band edge to longer wavelengths via the Franz–Keldysh effect, thus changing the light-guiding characteristics of the waveguide. Low-frequency characterization of a device shows modulation up to 28 dB at 1565 nm. When dc biased close to the negative differential conductance region, the RTD optical waveguide behaves as an electroabsorption modulator integrated with a wide bandwidth electrical amplifier, offering a potential advantage over conventional pn modulators