The Double-Pulse (DP) version of the Laser-Induced Forward Transfer (LIFT) technique holds great potential to improve the resolution and flexibility of printing applications. In this study, we investigate the transfer of copper. A long laser pulse is first applied to melt thin copper films deposited on a transparent substrate, followed by an ultrashort laser pulse to initiate the transfer of the liquid material towards a receiver substrate.
View Article and Find Full Text PDFPrecise timing of migration is crucial for animals targeting seasonal resources at locations encountered across their annual cycle. Upon departure, long-distance migrants need to anticipate unknown environmental conditions at their arrival site, and they do so with their internal annual clock. Here, we tested the hypothesis that long-distance migrants synchronize their circannual clock according to the phenology of their environment during the breeding season and therefore adjust their spring departure date according to the conditions encountered at their breeding site the year before.
View Article and Find Full Text PDFDriven by flexibility, precision, repeatability and eco-friendliness, laser-based technologies have attracted great interest to engineer or to analyze materials in various fields including energy, environment, biology and medicine. A major advantage of laser processing relies on the ability to directly structure matter at different scales and to prepare novel materials with unique physical and chemical properties. It is also a contact-free approach that makes it possible to work in inert or reactive liquid or gaseous environment.
View Article and Find Full Text PDFRedox enzymes can be envisioned as biocatalysts in various electrocatalytic-based devices. Among factors that play roles in bioelectrochemistry limitations, the effect of enzyme-enzyme neighboring interaction on electrocatalysis has rarely been investigated, although critical . We report in this work an in-depth study of gold nanoparticles prepared by laser ablation in the ultimate goal of determining the relationship between activity and enzyme density on electrodes.
View Article and Find Full Text PDFTungsten was chosen as a wall component to interact with the plasma generated by the International Thermonuclear Experimental fusion Reactor (ITER). Nevertheless, during plasma operation tritiated tungsten nanoparticles (W-NPs) will be formed and potentially released into the environment following a Loss-Of-Vacuum-Accident, causing occupational or accidental exposure. We therefore investigated, in the bronchial human-derived BEAS-2B cell line, the cytotoxic and epigenotoxic effects of two types of ITER-like W-NPs (plasma sputtering or laser ablation), in their pristine, hydrogenated, and tritiated forms.
View Article and Find Full Text PDFWestern France is at the crossroads of the migratory routes of two subspecies of black-tailed godwit, Limosa limosa. After leaving Iceland, the godwit L.l.
View Article and Find Full Text PDFWhen the energy of a short laser pulse is localized in a fluid material, a flow motion is induced that can lead to the generation of free-surface jets. This nozzle-free jetting process is exploited to print conductive materials, typically metal nanoparticle inks, but this approach remains limited to the transfer of low viscosity fluids with a minimum feature size of few micrometers. We introduce a dual-laser method to achieve reproducible high-aspect-ratio jets from thin solid films.
View Article and Find Full Text PDFBackground: Long-term benthic monitoring is rewarding in terms of science, but labour-intensive, whether in the field, the laboratory, or behind the computer. Building and managing databases require multiple skills, including consistency over time as well as organisation via a systematic approach. Here, we introduce and share our spatially explicit benthic database, comprising 11 years of benthic data.
View Article and Find Full Text PDFJ Colloid Interface Sci
May 2015
Controlling the preparation of nano/microsphere monolayers on large areas remains a difficult task but is crucial for several fabrication methods of highly-ordered periodic nanostructures. We demonstrate the preparation of ordered monolayers of few square centimeters with an extremely high coverage ratio (>98%) by implementing a modified protocol (MP) Langmuir Blodgett (LB) technique. We use octadecyl type hydrocarbon (C18) functionalized spherical particles (polystyrene and silica) with diameters in the range 1-5 μm, and a selected mixture of solvents for accurate control of the surface tension and particles' mobility at the water surface.
View Article and Find Full Text PDFThis paper extends the current understanding of the laser-induced forward transfer (LIFT) process to the multi-jets ejection problem. LIFT has already been used to print micrometer-sized droplets from a liquid donor substrate with single pulse experiments. Here we study the dynamics of the high-speed multi-jets formation from silver nanoparticles ink films with a time-resolved imaging technique.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2014
In this work, we investigate the effects of KrF nanosecond laser ablation on poly(methyl methacrylate) (PMMA) in combination with pyrene. Three materials containing PMMA were studied: (1) one doped with pure pyrene, (2) one doped with methyl 3-(1-pyrenyl)propanoate (so called alkylpyrene derivative thereafter), and (3) one grafted with pyrene. This last new material was developed by covalently bonding pyrene molecules to PMMA side-chains.
View Article and Find Full Text PDFMonodisperse silica nanospheres with sizes ranging from 250 to 725 nm were prepared and assembled into monolayers to produce regularly distributed light hot spots at the surface of oxidized silicon substrates when illuminated by a laser. Single UV nanosecond laser pulses were employed with energies above the local ablation threshold for the silicon dioxide layer, resulting in the direct formation of 2D periodically porous membranes on top of the silicon. The periodicity of the array was driven by the size of the self-assembled nanospheres.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
October 2011
By comparing finite-difference time-domain near field simulations and femtosecond laser ablation of thin films, we characterize in three dimensional-space photonic nanojets from microsphere arrays. We demonstrate periodic drilling of transparent films with thickness up to 100 nm (onto absorbing substrates) is feasible with 1-microm diameter silica spheres. Working with larger polystyrene spheres, the apparent increase of the propagation length of the photonic nanojets makes possible to drill films as thick as 500 nm.
View Article and Find Full Text PDFFine electrically-conductive patterns of silver nanoparticles ink have been laser printed using the laser-induced forward transfer (LIFT) technique. LIFT is a technique that offers the possibility of printing patterns with high spatial resolution from a wide range of materials in solid or liquid state. Influence of drying the ink film, previous to its transfer, on the printed droplet morphology is discussed.
View Article and Find Full Text PDFAn overview of pulsed laser-assisted methods for nanofabrication, which are currently developed in our Institute (LP3), is presented. The methods compass a variety of possibilities for material nanostructuring offered by laser-matter interactions and imply either the nanostructuring of the laser-illuminated surface itself, as in cases of direct laser ablation or laser plasma-assisted treatment of semiconductors to form light-absorbing and light-emitting nano-architectures, as well as periodic nanoarrays, or laser-assisted production of nanoclusters and their controlled growth in gaseous or liquid medium to form nanostructured films or colloidal nanoparticles. Nanomaterials synthesized by laser-assisted methods have a variety of unique properties, not reproducible by any other route, and are of importance for photovoltaics, optoelectronics, biological sensing, imaging and therapeutics.
View Article and Find Full Text PDFLaser-induced breakdown spectroscopy (LIBS) has been widely used to evaluate the elemental composition (e.g., minerals or metal accumulation) on vegetal tissues.
View Article and Find Full Text PDFBy use of a self-seeding technique, energetic nanosecond UV pulse trains of adjustable characteristics (number of pulses, pulse energy, interpulse delay) can be easily produced from an oscillator-amplifier XeCl laser system.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
December 2002
The physical phenomena involved in the interaction of a laser-generated plasma plume with a background gas are studied numerically. A three-dimensional combined model is developed to describe the plasma plume formation and its expansion in vacuum or into a background gas. The proposed approach takes advantages of both continuous and microscopic descriptions.
View Article and Find Full Text PDFAnn Med Interne (Paris)
April 1998
We report three cases of pseudohypertrophic chronic myopathy in patients with sarcoidosis. The patients were aged 41-50 years and were of African or mixed ethnic origin. All three patients had multiorgan sarcoidosis recently diagnosed by the presence of hiliary and/or mediastinal node enlargement with or without reticulomicronodulation in the lung fields.
View Article and Find Full Text PDFAnn Med Interne (Paris)
December 1999
Objective: To investigate the clinical, neuropsychological and imaging manifestations of Sjögren's syndrome (SS), a chronic auto-immune disease with peripheral and central nervous system (CNS) involvement.
Design/methods: Fourteen female patients suffering from confirmed SS underwent within 2 weeks: neurological examination, immunological staging, brain MRI, brain 99m Tc-HMPAO SPECT, psychological evaluation and in-depth neuropsychological testing.
Results: All patients showed neuropsychological abnormalities.
1. An antiserum raised against a 14 kDa beta-galactoside specific lectin from human brain (HBL14) was used to probe blots from samples of serum and cerebrospinal fluid. The only HBL14-immunoreactive material detected was heavy and light chains of a beta-galactoside-binding IgG fraction (lectin-like IgG).
View Article and Find Full Text PDFRev Neurol (Paris)
December 1992
Gerstmann-Sträussler-Scheinker's disease is a familial spongiform encephalopathy whose pathological hallmark is the existence--especially in the cerebellum--of numerous amyloid plaques. We report here the third clinicopathological case in a French family. Brain tissue from one of its members--initially described as familial Creutzfeldt-Jakob's disease--has been reported as successfully inoculated to monkeys.
View Article and Find Full Text PDFNeuropathologic study of an 82-year-old male who died from massive cerebral hemorrhage showed extensive amyloid angiopathy, with morphologic and immunohistochemical characteristics similar to those observed in Alzheimer's disease, associated with granulomatous angiitis, including the presence of numerous giant cells. Some of the giant cells contained, in their cytoplasm, congophilic material immunoreactive for the Alzheimer A4 peptide, supporting the hypothesis that the granulomatous angiitis may, in part, represent a foreign body reaction to A4 amyloid deposition.
View Article and Find Full Text PDFWe describe a patient with solitary plasmacytoma of the skull, in whom mononeuritis multiplex was the presenting manifestation. Some features of the POEMS syndrome (plasma cell dyscrasia with polyneuropathy, organomegaly, endocrinopathy, monoclonal [M] protein, skin changes), including thrombocytosis, were found. Muscle and nerve biopsies disclosed a small vessel hypersensitivity-type vasculitis and complement-fixing immune complex deposits in vessel walls.
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