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Band-edge photonic crystal lasers were fabricated and their temporal characteristics were minutely analyzed using a high resolution up-conversion system. The InGaAs/InP photonic crystal laser operates at room temperature at 1.55 microm with turn on time ranging from 17ps to 30ps.

Objective: The importance of prevention is increasingly recognised in most developed countries. General practitioners (GPs) have got a key role to play in this domain in primary care. But, the research evidence still concludes that GPs' preventive activities remain most of the time insufficient. The aim of our study was to contribute to this debate in adopting a more broad view of prevention-related activities to better understand the GPs practice in this matter. Our study was undertaken to measure the part of prevention-related activity hidden in each of the morbid conditions (MC) seen by the doctors daily., Methods: We carried out a cross-sectional study in a sample of 75 French GPs in the south suburb of Paris. We dropped the usual pre-established and limited list of specific preventive care activities to replace it with a list of 100 most common morbid conditions seen by the GPs in daily practice. The GPs were asked for each selected MC to rate on a five-item Likert scale the amount of primary and secondary prevention they generally offer during a patient visit., Results: All MC confounded, secondary prevention reached an average score of 3.2 (inter-quartile interval 2.82-3.58). The intensity of primary prevention was somewhat lower, but far from being negligible. Its average score was 2.3 (inter-quartile interval of 1.86-2.73). If more than 50% of the GPs declare a low intensity of primary prevention activity or even no primary prevention activity at all in nearly 3/4 of the MC encountered in their daily practice, they also declare that they carry out a considerable amount of primary prevention or in some cases spend the entire patient visit to primary prevention for MC covering more than 25% of their daily activity. Also, even if a majority of GPs did not give clear-cut scores for secondary prevention for 2/3 of the MC, they declare a considerable amount of it for the remaining 1/3 which covers more than 25% of their activity., Conclusion: Our study was useful to offer a more realistic view of the real place of the prevention-related activities in the GPs daily primary care practice even if we assess neither the appropriateness nor the quality of these activities.

We report on the continuous-wave operation of a band edge laser at room temperature near 1.55 mum in an InGaAs/InP photonic crystal. A flat dispersion band-edge photonic mode is used for surface normal operation. The photonic crystal slab is integrated onto a Silicon chip by means of Au/In bonding technology, which combines two advantages, efficient heat sinking and broad band reflectivity.

We report on reflection modulation results near 1.55 mum in InP-based two-dimensional photonic crystals. The fabrication technology uses a polymeric bonding technique to integrate the InP thin-slab onto a Silicon wafer. Reflectivity modulation greater than 90% is obtained by pumping at 810 nm with optical excitation densities of 15 muJ/cm(2). The resulting optical broadband modulation is based on the saturation of absorption of InGaAs quantum wells at a photonic mode frequency tunable by lithography.

We experimentally demonstrate excitability in a semiconductor two-dimensional photonic crystal. Excitability is a nonlinear dynamical mechanism underlying pulselike responses to small perturbations in systems possessing one stable state. We show that a band-edge photonic crystal resonator exhibits class II excitability, resulting from the nonlinear coupling between the high-Q optical mode, the charge-carrier density, and the fast (sub-micros) thermal dynamics. In this context, the critical slowing down of the electro-optical dynamics close to the excitable threshold can delay the optical response by an amount comparable to the duration of the output pulse (5 ns). The latter results from a short thermal dynamical excursion along a high local intensity manifold of the phase space.

We address, both experimentally and theoretically, phase and amplitude dynamics of the electromagnetic field in a two-dimensional photonic crystal when femtosecond pulses are injected. We demonstrate that the usual adiabatic approximation underlying the dynamics of field and carriers in a semiconductor resonator is no longer valid, since in general the photon lifetime cannot be neglected with respect to the carrier recombination lifetime. Parameter regions where adiabaticity is broken are shown, and the ubiquity of the observed dynamical scenario in the new generation of active photonic microresonators is predicted.

Erectile dysfunction (ED) affects men of all ages and results in considerable distress and impact on quality of life for those who suffer from it. As ED is associated with a wide variety of under-lying conditions and cardiovascular co-morbidities, there is a requirement for diversity of treatment options and several factors must be considered to customise and optimise therapy. In the ideal holistic approach to management of the ED patient, both primary care and specialist physicians have an important role to play. This article reports on a sequential approach for the diagnosis and treatment of ED, with an emphasis on 'shared care'. The deliberations are based on a pan-European inter-disciplinary group that met at the Lygon Arms, UK on 22 February 2002.

An unusual, severe delayed reaction to non-ionic intravenous contrast media was observed. A 44-year-old man underwent a computed tomography scan with non-ionic contrast media. Four hours later the patient collapsed with hypotension and cardiovascular shock. Aggressive management (including inotropic support and fluid resuscitation) was instituted in the intensive care unit. Rigorous imaging and biochemical and microbiological investigation failed to identify a source of this man's circulatory collapse. A rapid recovery ensued and at 3 months follow-up the patient was suffering no residual effects from this event. To our knowledge, this is only the second report of a severe delayed reaction to radiological contrast media and the first that manifested as a prolonged hypotensive syndrome.

Inheritance studies of gliadin loci on chromosomes 1A and 1B were carried out in the progeny from crosses between cv "Salmone" and six other common wheat varieties. The map distance between the Rg-1 locus for glume colour and the gliadin locus Gli-B1 on the satellite of chromosome 1B was calculated as 2.0±0.6 cM. An additional gliadin locus, Gli-B5, was mapped between Gli-B1 and Rg-1, 1.4 cM from the former. A genetic distance of 1.8±0.4 cM was obtained between the Hg-1 locus for hairy glumes and a gliadin locus that seems to be remote from Gli-A1 and homoeologous to Gli-B5. Statistically significant differences in recombination values were found in the six crosses, indicating the influence of genotype on the frequency of recombination. The similarity in chromosomal location of seed storage protein genes in wheat, barley and rye is discussed.