This work compares several Yb-doped large mode area (LMA) fiber amplifiers operating in the ∼50 ns regime at 1030 nm designed for airborne wind lidar application. The sinusoidal phase modulation applied to the signal enhances the SBS threshold by a factor 8.8 compared to a single frequency operation while still complying with lidar receiver spectral requirements.
View Article and Find Full Text PDFMultivalent elements are often incorporated into silicate glasses to enhance specific properties of the final product. However, for some of them, these properties strongly depend on the redox state of the multivalent elements. While the redox behavior of glasses containing a single multivalent element is well studied, research on the interaction between multiple multivalent elements is scarce.
View Article and Find Full Text PDFBackground: The use of multiagent FOLFIRINOX chemotherapy for pancreatic adenocarcinoma in a neoadjuvant setting has been associated with an increased rate of complete pathological response (CPR) after surgery. This study investigated the long-term outcomes of patients with CPR in a multicenter setting to identify prognostic factors for overall survival (OS) and recurrence-free survival (RFS).
Methods: This retrospective cohort study examined biopsy-proven pancreatic adenocarcinomas with CPR after neoadjuvant chemotherapy or chemoradiotherapy and surgery, between January 2006 and December 2023 across 22 French and 2 Belgian centers.
This paper is the result of a round robin activity run by the Technical Committee TC12, Pharma Packaging, of the International Commission on Glass (ICG). The study was motivated by a concern about the risk that the depyrogenation treatment of glass vials, when performed in an abnormal way that deviates from the usual procedure, may have a negative impact on the hydrolytic resistance of the container inner surface. The study was executed by using 10 ml clear type I Borosilicate glass vials representing four different compositions.
View Article and Find Full Text PDFBackground: The effects of hyperbaric oxygen therapy (HBOT) on wound healing have been demonstrated mainly in diabetic foot ulcer.
Objectives: To study the efficacy and safety of HBOT in chronic painful wounds, excluding diabetic foot ulcers.
Methods: From 2008 to 2021, patients with chronic wounds showing no clinical improvement for more than 1 month, who were in pain despite the use of level 2 or 3 analgesics, and who had undergone HBOT sessions, were included in a monocentric retrospective study.
This work presents what we believe is a new way to use a CTH:YAG crystal for spontaneous emission instead of laser emission. The spontaneous emission is collected in one main direction thanks to a luminescent concentrator configuration. The CTH:YAG is indirectly LED-pumped by a Ce:YAG delivering 3.
View Article and Find Full Text PDFBackground: Appropriate risk stratification for the difficulty of liver transplantation (LT) is essential to guide the selection and acceptance of grafts and avoid morbidity and mortality.
Methods: Based on 987 LTs collected from 5 centers, perioperative outcomes were analyzed across the 3 difficulty levels. Each LT was retrospectively scored from 0 to 10.
A Tm:LiYF laser operating on the H→ H transition is embedded in a high-power diode-pumped Nd:ASL laser for intracavity upconversion pumping at 1.05 µm. This leads to a record-high output power at 2.
View Article and Find Full Text PDFRedox control of glasses is paramount both to their fusion process and to obtaining the desired properties of high technological glasses. However, the link between melting parameters, such as temperature, furnace atmosphere, or quenching rate, and the redox state of the final products is poorly understood. In this work, in situ x-ray absorption near-edge structure (XANES) data at Ce L3-edge data were acquired at high temperatures on cerium-containing sodium aluminosilicate glasses, allowing the determination of thermodynamic constants necessary to predict the cerium redox state over a wide temperature range (900-1500 °C).
View Article and Find Full Text PDFWe demonstrate that chirped pulse up-conversion (CPU), a method routinely used with systems based on 1-kHz Titanium:Sapphire lasers, can be extended to a repetition rate of 100 kHz with an Ytterbium diode-pumped femtosecond amplifier. Individual mid-infrared spectra can thus be measured directly in the near infrared using a fast CMOS linescan camera. After an appropriate Fourier processing, a spectral resolution of 1.
View Article and Find Full Text PDFWe demonstrate nonlinear temporal compression of a vortex beam by propagation in a gas-filled capillary. Starting from an ytterbium-based laser delivering 700 μJ 640 fs pulses at a 100 kHz repetition rate, the vortex beam is generated using a spiral phase plate and coupled to a capillary where it excites a set of four modes that have an overlap integral of 97% with a Laguerre-Gauss LG mode. Nonlinear propagation of this hybrid, orbital angular momentum (OAM)-carrying mode results in temporal compression down to 74 fs at the output.
View Article and Find Full Text PDFWe demonstrate a continuously tunable mid-infrared source that produces narrowband radiation at 1981 nm and 2145 nm based on a tunable Yb-based hybrid MOPA pump and a backward-wave optical parametric oscillator (BWOPO). The BWOPO employs a PPRKTP crystal with 580 nm domain periodicity. The BWOPO has a record-low oscillation threshold of 19.
View Article and Find Full Text PDFFor a recent publication, the authors identified a seven-region model of mammal family distribution patterns, in which each unit contributes equally to the system's overall statistical characteristics of diversity, despite its individual units having measurably different levels of diversity and endemism. This systemization presents a highly efficient descriptive model that can possibly be interpreted as a form of natural classification. An additional analysis of the same mode is described here, in which the seven-region model of the distribution of mammal families' spatial affinities is shown to closely approach a most-probable-state arrangement, as assessed through combinatorics, raising some important questions about how macroevolutionary patterns might self-organize spatially.
View Article and Find Full Text PDFWe study a cascade laser scheme involving the H → H and F → H consecutive transitions in Tm-doped materials as a promising technique to favor laser emission at 2.3 µm. We examine the conditions in terms of the Tm doping levels for which the cascade laser is beneficial or not.
View Article and Find Full Text PDFFor, what we believe is, the first time, an Er:Cr:YSGG crystal is pumped by LEDs through a Ce:YAG luminescent concentrator. We demonstrate both laser emission at 2.79 µm and strong spontaneous emission at 1.
View Article and Find Full Text PDFFemtosecond laser sources with high repetition rate in the ultraviolet (UV) and vacuum UV (VUV) are fundamental tools enabling tabletop time-resolved and angle-resolved photoemission spectroscopy in solids. We describe a VUV source at 114 nm (10.8 eV) based on an industrial grade ytterbium-doped ultrafast laser, a nonlinear pulse width selection stage, and two cascaded frequency tripling stages, first in crystals, second in xenon.
View Article and Find Full Text PDFGraefes Arch Clin Exp Ophthalmol
February 2024
Background: Corneal perforation is an ophthalmic emergency. The conventional management of corneal perforation can be associated with severe complications especially in patients with ocular surface disease. Endothelial keratoplasty has been suggested as an alternative surgical technique for the management of corneal perforations.
View Article and Find Full Text PDFWe report on the first laser operation of a disordered Tm:CaGdAlO crystal on the H → H transition. Under direct pumping at 0.79 µm, it generates 264 mW at 2.
View Article and Find Full Text PDFWe characterize the intensity noise of two mid-infrared (MIR) ultrafast tunable (3.5-11 μm) sources based on difference frequency generation (DFG). While both sources are pumped by a high repetition rate Yb-doped amplifier delivering 200 μJ 300 fs at a central wavelength of 1030 nm, the first is based on intrapulse DFG (intraDFG), and the second on DFG at the output of an optical parametric amplifier (OPA).
View Article and Find Full Text PDFWe report on a bulk thulium laser operating on the H → H transition with pure upconversion pumping at 1064 nm by an ytterbium fiber laser (addressing the F → F excited-state absorption (ESA) transition of Tm ions) generating 433 mW at 2291 nm with a slope efficiency of 7.4% / 33.2% vs.
View Article and Find Full Text PDFCerium-doped lutetium-yttrium oxyorthosilicate (Ce:LYSO) is a well-known single crystal scintillator used in medical imaging and security scanners. Recent development of high power UV LED, matching its absorption band, questions the possibility to use Ce:LYSO in a new way: as LED-pumped solid-state light source. Since Ce:LYSO is available in large size crystals, we investigate its potential as a luminescent concentrator.
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