Watt-level deep-UV subnanosecond laser system based on Nd-doped fiber at 229 nm.

We report an efficient deep-UV master-oscillator power amplifier (MOPA) laser system at 229 nm that generates 350 ps pulses at 2 MHz repetition rate with an average power of 1.2 W. The use of a polarization-maintaining large mode area neodymium-doped fiber operating on the F→I transition allows high-power laser emission of up to 28 W near 915 nm in the sub-nanosecond regime with low spectral broadening.

Mode-locked all-PM Nd-doped fiber laser near 910 nm.

We present a compact passively mode-locked fiber laser emitting near 910 nm with an all-polarization-maintaining fiber laser architecture. The ring-cavity laser configuration includes a core-pumped neodymium-doped fiber as a gain medium and a semiconductor saturable absorber mirror as a passive mode-locking element. A bandpass filter is used to suppress parasitic emission near 1.

Linearly-polarized pulsed Nd-doped fiber MOPA at 905 nm and frequency conversion to deep-UV at 226 nm.

We present the first frequency-quadrupled linearly-polarized Q-switched neodymium-doped fiber laser generating > 500 mW average power at 226 nm. For this purpose, an amplified Q-switched oscillator using novel large-mode-area (LMA) fibers and generating up to 24 W average power (15 kW peak power) at 905 nm was developed. Two nonlinear frequency conversion stages using a LBO crystal for SHG and a BBO crystal for FHG generate respectively up to 4.

Diffraction limited 195-W continuous wave laser emission at 2.09 µm from a Tm, Ho-codoped single-oscillator monolithic fiber laser.

We present a bi-directionally 793-nm diode-pumped Tm, Ho-codoped silica polarization maintaining double-clad all-fiber laser based on a single-oscillator architecture emitting 195 W at 2.09 µm in continuous wave mode of operation, with a beam quality near the diffraction limit (M = 1.08).

Use of high dose cyproterone acetate and risk of intracranial meningioma in women: cohort study.

Objective: To assess the risk of meningioma associated with use of high dose cyproterone acetate, a progestogen indicated for clinical hyperandrogenism.

Design: Observational cohort study.

Setting: Data from SNDS, the French administrative healthcare database, between 2007 and 2015.

Realization and simulation of high-power holmium doped fiber lasers for long-range transmission.

We report on our realization of a high-power holmium doped fiber laser, together with the validation of our numerical simulation of the laser. We first present the measurements of the physical parameters that are mandatory to model accurately the laser-holmium interactions in our silica fiber. We then describe the realization of the clad-pumped laser, based on a triple-clad large mode area holmium (Ho) doped silica fiber.

Dissipative soliton resonance in a mode-locked Nd-fiber laser operating at 927 nm.

We demonstrate for the first time, to our knowledge, an all-polarization-maintaining double-clad neodymium fiber laser operating in the dissipative soliton resonance (DSR) regime where stable mode-locking is achieved using a nonlinear amplifying loop mirror (NALM) with large normal dispersion in a figure-8 cavity design. The laser thereby generates square-shaped nanosecond pulses whose duration linearly scales with pump power from 0.5 up to 6 ns, with a maximum energy of 20 nJ.

55 W actively Q-switched single oscillator Tm, Ho-codoped silica polarization maintaining 2.09 µm fiber laser.

A bidirectional 793 nm diode-pumped actively Q-switched Tm, Ho-codoped silica polarization-maintaining (PM) double-clad (DC) fiber laser is reported. With this fiber laser, 55 W of average output power with 100 ns pulse width at 200 kHz repetition rate and 2.09 µm wavelength is obtained.

Watt-level narrow-linewidth fibered laser source at 852 nm for FIB application.

We realize a 1 W all-fibered polarized compact and robust laser source at 852 nm for laser cooling of cesium atoms. The architecture is based on the sum-frequency generation of 1540 and 1908 nm lasers, realized through a periodically poled lithium niobate waveguide with a conversion efficiency of 40%. A linewidth of 20 kHz is achieved with the development of a distributed feedback fiber laser at 1908 nm.

Radiation hardened high-power Er/Yb-codoped fiber amplifiers for free-space optical communications.

The radiation responses of different high-power erbium/ytterbium-codoped fiber amplifiers (HP-EYDFA) have been investigated up to 100 krad (SiO) dose levels. These devices are able to deliver 20 W of signal output power at 1565 nm by pumping at 915 nm (43 W) radiation tolerant (Er/Yb) or radiation hardened (ErYbCe) active few mode fibers; these performances are needed for free-space communications between low-orbit satellites and ground transceivers. X-ray irradiation results show that, thanks to a positive influence of the photo- and thermal-bleaching phenomena associated with such high-power operating conditions, the gain degradation levels of HP-EYDFA based on radiation hardened fibers remain below 6% after 100 krad at an accelerated dose rate of 3.

7.5 W blue light generation at 452 nm by internal frequency doubling of a continuous-wave Nd-doped fiber laser.

We present the first frequency-doubled neodymium-doped fiber laser generating multi-watt CW power near 450 nm. A bow-tie resonator incorporating a LBO nonlinear crystal is integrated within a Nd-doped fiber laser emitting near 900 nm. This scheme achieves an IR to blue conversion efficiency close to 55% without any active control of the internal resonant cavity.

Beat note stabilization in dual-polarization DFB fiber lasers by an optical phase-locked loop.

A fully fibered microwave-optical source at 1.5 µm is studied experimentally. It is shown that the beat note between two orthogonally polarized modes of a distributed-feedback fiber laser can be efficiently stabilized using an optical phase-locked loop.

Watt-level single-frequency tunable neodymium MOPA fiber laser operating at 915-937 nm.

We have developed a Watt-level single-frequency tunable fiber laser in the 915-937 nm spectral window. The laser is based on a neodymium-doped fiber master oscillator power amplifier architecture, with two amplification stages using a 20 mW extended cavity diode laser as seed. The system output power is higher than 2 W from 921 to 933 nm, with a stability better than 1.

Transverse mode selection in a Nd-doped fiber amplifier at 910 nm.

Selective amplifications of LP fundamental mode and higher order modes LP and LP are demonstrated in a double-pass Nd-doped LMA fiber amplifier operating at 910 nm. A multimode core fiber Bragg grating is employed to select a single guided mode by simply adjusting the wavelength of the seed signal. Although the M parameter of the output beam from the amplifier was ~2.

Early detection and curative treatment of hepatocellular carcinoma: A cost-effectiveness analysis in France and in the United States.

Unlabelled: Hepatocellular carcinoma (HCC) is the leading cause of death in patients with cirrhosis. Patients outside clinical trials seldom benefit from evidence-based monitoring. The objective of this study was to estimate the cost-effectiveness of complying with HCC screening guidelines.

Optical parametric generation by a simultaneously Q-switched mode-locked single-oscillator thulium-doped fiber laser in orientation-patterned gallium arsenide.

Optical parametric generation is demonstrated in orientation-patterned gallium arsenide, pumped by a novel single-oscillator simultaneously Q-switched and mode-locked thulium-doped fiber laser, downconverting the pump radiation into the mid-infrared wavelength regime. The maximum output energy reached is greater than 2.0 μJ per pump pulse.

High-peak-power single-oscillator actively Q-switched mode-locked Tm-doped fiber laser and its application for high-average output power mid-IR supercontinuum generation in a ZBLAN fiber.

A single-oscillator actively Q-switched mode-locked (QML) thulium-doped silica fiber laser is presented and used to pump a ZrF-BaF-LaF-AlF-NaF (ZBLAN) fiber for mid-infrared (mid-IR) supercontinuum (SC) generation. The fiber laser provided high-peak-power levels directly from the oscillator delivering single mode-locked pulse energies up to 48 μJ, being 2-4 orders of magnitude higher than conventional continuous wave mode-locked lasers. By pumping a ZBLAN fiber specially designed for high-output-power SC generation, 7.

Cost Effectiveness of Free Access to Smoking Cessation Treatment in France Considering the Economic Burden of Smoking-Related Diseases.

Context: In France more than 70,000 deaths from diseases related to smoking are recorded each year, and since 2005 prevalence of tobacco has increased. Providing free access to smoking cessation treatment would reduce this burden. The aim of our study was to estimate the incremental cost-effectiveness ratios (ICER) of providing free access to cessation treatment taking into account the cost offsets associated with the reduction of the three main diseases related to smoking: lung cancer, chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD).

Annual cost of stable coronary artery disease in France: A modeling study.

Background: Few studies have analyzed the cost of treatment of chronic angina pectoris, especially in European countries.

Aim: To determine, using a modeling approach, the cost of care in 2012 for 1year of treatment of patients with stable angina, according to four therapeutic options: optimal medical therapy (OMT); percutaneous coronary intervention with bare-metal stent (PCI-BMS); PCI with drug-eluting stent (PCI-DES); and coronary artery bypass graft (CABG).

Methods: Six different clinical scenarios that could occur over 1year were defined: clinical success; recurrence of symptoms without hospitalization; myocardial infarction (MI); subsequent revascularization; death from non-cardiac cause; and cardiac death.

Extended tunability of Nd-doped fiber lasers operating at 872-936 nm.

Efficient operation of an Nd-doped fiber laser operating in a wavelength-tunable configuration using a volume Bragg grating (VBG) is reported in this Letter. A high-power operation on the 4F3/2-4I9/2 transition of Nd3+ at short wavelengths below 900 nm is demonstrated for the first time in silica fibers. A high-efficiency (47% laser conversion) output power up to 22 W and a narrow linewidth of 0.

Actively mode-locked Tm(3+)-doped silica fiber laser with wavelength-tunable, high average output power.

A diode-pumped, actively mode-locked high-power thulium (Tm)-doped double-clad silica fiber laser is demonstrated, providing an average output power in mode-locked (continuous wave) operation of 53 W (72 W) with a slope efficiency of 34% (38%). Mode-locking in the 6th-harmonic order was obtained by an acousto-optic modulator driven at 66 MHz without dispersion compensation. The shortest measured output pulse width was 200 ps.

6.5 W ZnGeP(2) OPO directly pumped by a Q-switched Tm(3+)-doped single-oscillator fiber laser.

An efficient actively Q-switched Tm-doped single-oscillator fiber laser based on a silica polarization-maintaining (PM) double-clad fiber provided average powers of 23 W at pulse widths of 65 ns at 40 kHz pulse repetition frequency. It was used to directly pump a ZnGeP optical parametric oscillator (OPO). Up to 6.

Evaluating structured care for diabetes: can calibration on margins help to avoid overestimation of the benefits? An illustration from French diabetes provider networks using data from the ENTRED Survey.

Objective: While there is growing evidence on the effectiveness of structured care for diabetic patients in trial settings, standard population level evaluations may misestimate intervention benefits due to patient selection. In order to account for potential biases in measuring intervention benefits, we tested the impact of calibration on margins as a novel adjustment method in an evaluation context compared with simple poststratification.

Research Design And Methods: We compared the results of a before-after evaluation on HbA1c levels after 1 year of enrollment in a French diabetes provider network (DPN) using an unadjusted sample and samples adjusted by simple poststratification to results obtained after adjustment via calibration on margins to the general diabetic population's characteristics using a national cross-sectional sample of diabetic patients.

Radiation-hard erbium optical fiber and fiber amplifier for both low- and high-dose space missions.

We present a new structure for erbium-doped optical fibers [hole-assisted carbon-coated, (HACC)] that, combined with an appropriate choice of codopants in the core, strongly enhances their radiation tolerance. We built an erbium-doped fiber amplifier based on this HACC fiber and characterize its degradation under γ-ray doses up to 315 krad (SiO2) in the ON mode. The 31 dB amplifier is practically radiation insensitive, with a gain change of merely -2.

20 W continuous-wave cladding-pumped Nd-doped fiber laser at 910 nm.

We demonstrate a double-clad fiber laser operating at 910 nm with a record power of 20 W. Laser emission on the three-level scheme is enabled by the combination of a small inner cladding-to-core diameter ratio and a high brightness pump source at 808 nm. A laser conversion efficiency as high as 44% was achieved in CW operating regime by using resonant fiber Bragg reflectors at 910 nm that prevent the lasing at the 1060 nm competing wavelength.