Spore-forming bacteria as pharmaceutical factories

Many Bacilli form dormant structures, spores, which routinely survive physical, chemical and biological challenge. How do spores encapsulate their contents, and could it be possible to mimic or adapt them to make better drug products? Key spore component 2,6-dipicolinic acid (DPA) is necessary for protein stability, but investigation of its role is confounded with that of water content. Tests replacing DPA with chemical analogues were not successful, but led to the novel approach of doping spores with extra DPA. Various Bacillus species, in the main B. subtilis and B. thuringiensis, have been engineered to produce, for the first time, fragments of a humanized monoclonal antibody: kindly provided by Medimmune. It is possible to produce antibodies inside the spore core. This work proposes for the first time that such therapeutic spores might lack an outer coat, and demonstrates that antibody production continues. It is understood they continue to resist most challenges including wet heat, which damages proteins, yet they become susceptible to lysozyme. Such spores, further developed to lyse in presence of intestinal, though not gastric fluid, may have use in oral delivery. Cry1Ac of B. thuringiensis offers an alternative; large protein crystals are produced during sporulation. Here, various fluorescent fusions that maintain fluorescence over months were developed and investigated in detail. For the first time, fluorescent antibody crystals were produced. In addition to drug delivery, these fusions offer a novel approach to crystallization of intransigent proteins, for structural studies. This work shows that it might be feasible to use spores as pharmaceutical formulations. A number of challenges remain: from fabrication, through limits of current good manufacturing practice, to engineering biology to protect the environment and commercial interests. Bacterial spores have for the past century and a half been known for their dormancy, and it’s about time engineers took advantage.Medimmune (now AZ's biologics division) part funded the studentship and lab costs. Reference MA-417339

Pilgrimage Project

The University of North Florida Pilgrimage Project combines interdisciplinary approaches with digital and STEM technologies and applies them to the study of pilgrimage with a special focus on the Camino de Santiago

Particulate emissions from commercial shipping: chemical, physical, and optical properties

, 39% OM, and 15% BC and differs from inventories that used 81%, 14%, and 5% and 31%, 63%, and 6% SO 4 2À , OM, and BC, respectively. SO 4 2À and OM mass were found to be dependent on fuel sulfur content as were SSA, hygroscopicity, and CCN concentrations. BC mass was dependent on engine type and combustion efficiency. A plume evolution study conducted on one vessel showed conservation of particle light absorption, decrease in CN > 5 nm, increase in particle hygroscopicity, and an increase in average particle size with distance from emission. These results suggest emission of small nucleation mode particles that subsequently coagulate/condense onto larger BC and OM. This work contributes to an improved understanding of the impacts of ship emissions on climate and air quality and will also assist in determining potential effects of altering fuel standards

Energy Development in Colorado’s Pawnee National Grasslands: Mapping and Measuring the Disturbance Footprint of Renewables and Non-Renewables

This paper examines the pattern and extent of energy development in steppe landscapes of northeast Colorado, United States. We compare the landscape disturbance created by oil and gas production to that of wind energy inside the Pawnee National Grasslands eastern side. This high-steppe landscape consists of a mosaic of federal, state, and private lands where dominant economic activities include ranching, agriculture, tourism, oil and gas extraction, and wind energy generation. Utilizing field surveys, remote sensing data and geographic information systems techniques, we quantify and map the footprint of energy development at the landscape level. Findings suggest that while oil and gas and wind energy development have resulted in a relatively small amount of habitat loss within the study area, the footprint stretches across the entire zone, fragmenting this mostly grassland habitat. Futhermore, a third feature of this landscape, the non-energy transportation network, was also found to have a significant impact. Combined, these three features fragment the entire Pawnee National Grasslands eastern side, leaving very few large intact core, or roadless areas. The primary objective of this ongoing work is to create a series of quantifiable and replicable surface disturbance indicators linked to energy production in semi-arid grassland environments. Based on these, and future results, we aim to work with industry and regulators to shape energy policy as it relates to environmental performance, with the aim of reducing the footprint and thus increasing the sustainability of these extractive activities

Laserix : Une plate-forme pour le développement large spectre d’applications de la lumière intense

International audienceLASERIX est une plateforme de l’IJClab sur le campus de l’Université Paris Saclay. Le laser est une chaîne CPA de niveau 50 TW à 10 Hz. Des thématiques de recherche en rapport avec la physique des deux infinis sont menées en parallèle avec une vocation affirmée d’ouverture à la formation. Nous présentons un panorama sur les sources XUV de lumière structurée, l’accélération laser plasma et des études prospectives sur l’étude des propriétés du vide soumis à un champ électromagnétique ultra-intense

Caractérisation mono-tir du front d'onde d'un vortex extrême ultra-violet de haute charge topologique

International audienceWir präsentieren eine experimentelle Intensität und Wellenfront-Charakterisierung des Infrarot-Laser sowie den extremen ultravioletten Wirbel, der durch hohe harmonische Erzeugung in einem Medium der erweiterten Generation erhalten wurde. In einer langen Fokussierungsgeometrie ermöglicht ein intensiver Wirbelstrahl, der durch phasenangepasste, absorptionsbegrenzte hohe harmonische Erzeugung in einer 15 mm langen mit Argon gefüllten Gaszelle erhalten wird, die Einzelschuss-Charakterisierung der Wirbelstruktur. Darüber hinaus validiert unsere Studie das Erhaltung Gesetz der Drehimpulses auch für ein solches Medium der erweiterten Generation.We present an experimental intensity and wavefront characterization of the infrared vortex driver as well as the extreme ultraviolet vortex obtained through high harmonic generation in an extended generation medium. In a loose focusing geometry, an intense vortex beam obtained through phase-matched absorption-limited high harmonic generation in a 15 mm long Argon filled gas-cell permits single-shot characterization of the vortex structure. Moreover, our study validates the multiplicative law of momentum conservation even for such an extended generation medium.Nous présentons une caractérisation expérimentale de l'intensité et du front d'onde d'un faisceau laser vortex infrarouge, ainsi que du vortex extrême ultraviolet obtenu par génération d'harmoniques d'ordre élevé dans un milieu générateur long. Dans une géométrie de longue focalisation, nous obtenons un faisceau vortex intense par génération d'harmoniques en régime d'accord de phase limité par l'absorption dans une cellule d'argon de 15mm, permettant ainsi une caractérisation mono-tir de la structure vorticielle. Notre étude valide également la loi de conservation du moment cinétique, même dans un milieu de génération étendu

Towards subpicosecond pulses from solid target plasma based seeded soft X-ray laser

International audienceWe investigate the coherence of plasma-based soft X-ray laser (XRL) for different conditions that can alter the electron density in the gain region. We first measure the source temporal coherence in amplified spontaneous emission (ASE) mode. We develop a data analysis procedure to extract both its spectral width and pulse duration. These findings are in agreement with the spectral line shape simulations and seeded operation experimental results. Utilizing the deduced spectral width and pulse duration in a one-dimensional Bloch-Maxwell code, we reproduce the experimental temporal coherence properties of the seeded-XRL. Finally, we demonstrate efficient lasing in ASE and seeded mode at an electron density two times higher than the routine conditions. In this regime, using Bloch-Maxwell modeling, we predict the pulse duration of the seeded XRL to be ∼ 500 f s

Status report of the ESCULAP project at Orsay: External injection of low energy electrons in a Plasma

International audienceThe ESCULAP project aims at studying external injection of low energy (10 MeV) electrons in a plasma in the quasilinear regime. This facility will use the photo injector PHIL and the high power laser LASERIX. We will give a status report of the preliminary work on the facility and the status of the two machines. We will also present the results of simulations showing the expected performances of the facility

Synchronization of a Photo-Injector and a High Power Laser With Independent Clocks

International audienceThe plasma acceleration project ESCULAP (ElectronS CoUrts pour L'Acc\'el\'eration Plasma) aims at studying electrons injection into a laser plasma accelerator. This requires the injection of short electron bunches generated by the photo injector PHIL (Photo injector at LAL) into a plasma wave by the high power femtosecond Laser LASERIX. As a first step we have studied how to synchronize PHIL and LASERIX. As these two machines had not been initially designed to work together, simple synchronization solutions were not available. We detail here the synchronisation scheme that we have tested and the experimental results obtained