Optical second harmonic generation in LiBO modulated by intense femtosecond X-ray pulses.

Many of the scientific applications for X-ray free-electron lasers seek to exploit the ultrashort pulse durations of intense X-rays to obtain femtosecond time resolution of various processes in a "pump-probe" scheme. One of the limiting factors for such experiments is the timing jitter between the X-rays and ultrashort pulses from more conventional lasers operating at near-optical wavelengths. In this work, we investigate the potential of using X-ray-induced changes in the optical second harmonic generation efficiency of a nonlinear crystal to retrieve single-shot arrival times of X-ray pulses with respect to optical laser pulses.

SwissFEL Aramis beamline photon diagnostics. Erratum.

The list of authors in the paper by Juranić et al. (2018) [J. Synchrotron Rad.

Experimental station Bernina at SwissFEL: condensed matter physics on femtosecond time scales investigated by X-ray diffraction and spectroscopic methods.

The Bernina instrument at the SwissFEL Aramis hard X-ray free-electron laser is designed for studying ultrafast phenomena in condensed matter and material science. Ultrashort pulses from an optical laser system covering a large wavelength range can be used to generate specific non-equilibrium states, whose subsequent temporal evolution can be probed by selective X-ray scattering techniques in the range 2-12 keV. For that purpose, the X-ray beamline is equipped with optical elements which tailor the X-ray beam size and energy, as well as with pulse-to-pulse diagnostics that monitor the X-ray pulse intensity, position, as well as its spectral and temporal properties.

SwissFEL Aramis beamline photon diagnostics.

The SwissFEL Aramis beamline, covering the photon energies between 1.77 keV and 12.7 keV, features a suite of online photon diagnostics tools to help both users and FEL operators in analysing data and optimizing experimental and beamline performance.

THz streak camera method for synchronous arrival time measurement of two-color hard X-ray FEL pulses.

The two-color operation of free electron laser (FEL) facilities allows the delivery of two FEL pulses with different energies, which opens new possibilities for user experiments. Measuring the arrival time of both FEL pulses relative to the external experimental laser and to each other improves the temporal resolution of the experiments using the two-color FEL beam and helps to monitor the performance of the machine itself. This work reports on the first simultaneous measurement of the arrival times of two hard X-ray FEL pulses with the THz streak camera.

Opportunities for Chemistry at the SwissFEL X-ray Free Electron Laser.

X-ray techniques have long been applied to chemical research, ranging from powder diffraction tools to analyse material structure to X-ray fluorescence measurements for sample composition. The development of high-brightness, accelerator-based X-ray sources has allowed chemists to use similar techniques but on more demanding samples and using more photon-hungry methods. X-ray Free Electron Lasers (XFELs) are the latest in the development of these large-scale user facilities, opening up new avenues of research and the possibility of more advanced applications for a range of research.

The SwissFEL Experimental Laser facility.

The hard X-ray laser SwissFEL at the Paul Scherrer Institute is currently being commissioned and will soon become available for users. In the current article the laser facility is presented, an integral part of the user facility, as most time-resolved experiments will require a versatile optical laser infrastructure and precise information about the relative delay between the X-ray and optical pulse. The important key parameters are a high availability and long-term stability while providing advanced laser performance in the wavelength range from ultraviolet to terahertz.

Population structure and comparative genome hybridization of European flor yeast reveal a unique group of Saccharomyces cerevisiae strains with few gene duplications in their genome.

Wine biological aging is a wine making process used to produce specific beverages in several countries in Europe, including Spain, Italy, France, and Hungary. This process involves the formation of a velum at the surface of the wine. Here, we present the first large scale comparison of all European flor strains involved in this process.

Genetic analysis of geraniol metabolism during fermentation.

Geraniol produced by grape is the main precursor of terpenols which play a key role in the floral aroma of white wines. We investigated the fate of geraniol during wine fermentation by Saccharomyces cerevisiae. The volatile compounds produced during fermentation of a medium enriched with geraniol were extracted by Stir-bar sorptive extraction and analysed by GC-MS.

QTL mapping of the production of wine aroma compounds by yeast.

Background: Wine aroma results from the combination of numerous volatile compounds, some produced by yeast and others produced in the grapes and further metabolized by yeast. However, little is known about the consequences of the genetic variation of yeast on the production of these volatile metabolites, or on the metabolic pathways involved in the metabolism of grape compounds. As a tool to decipher how wine aroma develops, we analyzed, under two experimental conditions, the production of 44 compounds by a population of 30 segregants from a cross between a laboratory strain and an industrial strain genotyped at high density.

Ecological success of a group of Saccharomyces cerevisiae/Saccharomyces kudriavzevii hybrids in the northern european wine-making environment.

The hybrid nature of lager-brewing yeast strains has been known for 25 years; however, yeast hybrids have only recently been described in cider and wine fermentations. In this study, we characterized the hybrid genomes and the relatedness of the Eg8 industrial yeast strain and of 24 Saccharomyces cerevisiae/Saccharomyces kudriavzevii hybrid yeast strains used for wine making in France (Alsace), Germany, Hungary, and the United States. An array-based comparative genome hybridization (aCGH) profile of the Eg8 genome revealed a typical chimeric profile.

Activation of two different resistance mechanisms in Saccharomyces cerevisiae upon exposure to octanoic and decanoic acids.

Medium-chain fatty acids (octanoic and decanoic acids) are well known as fermentation inhibitors. During must fermentation, the toxicity of these fatty acids is enhanced by ethanol and low pH, which favors their entrance in the cell, resulting in a decrease of internal pH. We present here the characterization of the mechanisms involved in the establishment of the resistance to these fatty acids.

High-repetition-rate optical parametric chirped-pulse amplifier producing 1-microJ, sub-100-fs pulses in the mid-infrared.

We present a high-repetition-rate, femtosecond optical parametric chirped pulse amplifier (OPCPA). Its seed signal is obtained by difference frequency generation from the two-branch output of a commercially available Er:fiber laser amplifier. The optical parametric amplifier is pumped by a commercially available diode-pumped solid-state laser.

Male reproductive success and multiple paternity in wild, low-density populations of the adder (Vipera berus).

We studied for the first time the occurrence of multiple paternity, male reproductive success, and neonate survival in wild, low-density adder (Vipera berus) populations using 13 microsatellite loci. Paternity was assigned for 15 clutches, collected during 3 years. Our data demonstrated that multiple paternity can occur at a high level (69%) in natural populations of V.

Mid-infrared difference-frequency generation of ultrashort pulses tunable between 3.2 and 4.8 microm from a compact fiber source.

We report single-pass difference-frequency generation of mid-infrared femtosecond pulses tunable in the 3.2-4.8 microm range from a two-branch mode-locked erbium-doped fiber source.

Characterization of natural hybrids of Saccharomyces cerevisiae and Saccharomyces bayanus var. uvarum.

Nine yeast strains were isolated from spontaneous fermentations in the Alsace area of France, during the 1997, 1998 and 1999 grape harvests. Strains were characterized by pulsed-field gel electrophoresis, PCR-restriction fragment length polymorphism (RFLP) of the MET2 gene, delta-PCR, and microsatellite patterns. Karyotypes and MET2 fragments of the nine strains corresponded to mixed chromosomal bands and restriction patterns for both Saccharomyces cerevisiae and Saccharomyces bayanus var.

Evolution of the population of Saccharomyces cerevisiae from grape to wine in a spontaneous fermentation.

To determine the grape or winery origin of the Saccharomyces cerevisiae involved in spontaneous fermentation, musts were collected at different stages of wine-making process and fermented. First, grapes were collected in two different vineyards and crushed at the laboratory. Second, musts were collected after crushing and clarification in the cellar.

An N-proximal sequence of the alfalfa mosaic virus movement protein is necessary for association with cell walls in transgenic plants.

We have made transgenic tobacco plants (Nicotiana tabacum, cv. Xanthi nc) expressing the movement protein (P3, 300 amino acids) of alfalfa mosaic virus (A1MV) and two N-terminally deleted proteins lacking respectively 12 and 77 amino acids of the P3 sequence (P3 delta[1-12] and P3 delta[1-77]). The same proteins were expressed in recombinant yeast.

Nucleic acid-binding properties of the alfalfa mosaic virus movement protein produced in yeast.

The movement protein of alfalfa mosaic virus (P3) was purified from yeasts transformed with an expression vector containing the P3 gene. Its nucleic acid-binding properties were tested by electrophoretic retardation, nitrocellulose retention, and RNA-protein cross-linking. The recombinant protein had a higher affinity for single-stranded RNA and DNA than for double-stranded nucleic acids.

Treatment of patients with chronic granulomatous disease with recombinant human interferon-gamma does not improve neutrophil oxidative metabolism, cytochrome b558 content or levels of four anti-microbial proteins.

Recombinant interferon-gamma (rIFN-gamma) has been described to enhance phagocyte functions in vitro and in vivo in several patients with chronic granulomatous disease (CGD). To demonstrate the clinical usefulness of this treatment, 128 patients were treated in a randomized, double-blind multi-centre study with a placebo preparation or with rIFN-gamma. We analysed parameters of neutrophil oxidative and non-oxidative metabolism in 16 patients enrolled in this study.

Nucleic acid binding properties of the 92-kDa replicase subunit of alfalfa mosaic virus produced in yeast.

The 92-kDa non-structural protein of alfalfa mosaic virus (one of the replicase subunits) was synthesized by Saccharomyces cerevisiae transformed with a recombinant expression vector. The yeast-expressed protein had the immunological and size characteristics of the naturally made viral protein. It was partially purified and its nucleic acid binding properties were tested by gel-retardation electrophoresis and nitrocellulose adsorption.

Biologically active transcripts of alfalfa mosaic virus RNA3.

Transcripts of the bicistronic RNA3 of alfalfa mosaic virus were synthesized using the in vitro T7 run-off transcription system. Synthetic RNA3 containing one additional G nucleotide at the 5' end were found to be infectious when coinoculated with RNA1 and RNA2 and coat protein.