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Thermal infrared data collected by the Thermal Emission Spectrometer (TES) and Thermal Emission Imaging System (THEMIS) instruments have significantly impacted the understanding of martian surface mineralogy. Spatial/temporal variations in igneous lithologies; the discovery of quartz, carbonates, and chlorides; and the widespread identification of amorphous, silica-enriched materials reveal a planet that has experienced a diversity of primary and secondary geo-logic processes including igneous crustal evolution, regional sedimentation, aqueous alteration, and glacial/periglacial activity.
Quaternary processes and environmental changes are often difficult to assess in remote subantarctic islands due to high surface erosion rates and overprinting of sedimentary products in locations that can be a challenge to access. We present a set of high-resolution, multichannel seismic lines and complementary multibeam bathymetry collected off the eastern (leeward) side of the subantarctic Auckland Islands, about 465 km south of New Zealand's South Island. These data constrain the erosive and depositional history of the island group, and they reveal an extensive system of sediment-filled valleys that extend offshore to depths that exceed glacial low-stand sea level. Although shallow, marine, U-shaped valleys and moraines are imaged, the rugged offshore geomorphology of the paleovalley floors and the stratigraphy of infill sediments suggests that the valley floors were shaped by submarine fluvial erosion, and subsequently filled by lacustrine, fjord, and fluvial sedimentary processes.
The deep subsurface of other planetary bodies is of special interest for robotic and human exploration. The subsurface provides access to planetary interior processes, thus yielding insights into planetary formation and evolution. On Mars, the subsurface might harbour the most habitable conditions. In the context of human exploration, the subsurface can provide refugia for habitation from extreme surface conditions. We describe the fifth Mine Analogue Research (MINAR 5) programme at 1 km depth in the Boulby Mine, UK in collaboration with Spaceward Bound NASA and the Kalam Centre, India, to test instruments and methods for the robotic and human exploration of deep environments on the Moon and Mars. The geological context in Permian evaporites provides an analogue to evaporitic materials on other planetary bodies such as Mars. A wide range of sample acquisition instruments (NASA drills, Small Planetary Impulse Tool (SPLIT) robotic hammer, universal sampling bags), analytical instruments (Raman spectroscopy, Close-Up Imager, Minion DNA sequencing technology, methane stable isotope analysis, biomolecule and metabolic life detection instruments) and environmental monitoring equipment (passive air particle sampler, particle detectors and environmental monitoring equipment) was deployed in an integrated campaign. Investigations included studying the geochemical signatures of chloride and sulphate evaporitic minerals, testing methods for life detection and planetary protection around human-tended operations, and investigations on the radiation environment of the deep subsurface. The MINAR analogue activity occurs in an active mine, showing how the development of space exploration technology can be used to contribute to addressing immediate Earth-based challenges. During the campaign, in collaboration with European Space Agency (ESA), MINAR was used for astronaut familiarization with future exploration tools and techniques. The campaign was used to develop primary and secondary school and primary to secondary transition curriculum materials on-site during the campaign which was focused on a classroom extra vehicular activity simulation.
Catheter-associated urinary tract infections (CAUTIs) are among the most common hospital-acquired infections (HAIs). Reducing CAUTI rates has become a major focus of attention due to increasing public health concerns and reimbursement implications.
To implement and describe a multifaceted intervention to decrease CAUTIs in our ICUs with an emphasis on indications for obtaining a urine culture.
A project team composed of all critical care disciplines was assembled to address an institutional goal of decreasing CAUTIs. Interventions implemented between year 1 and year 2 included protocols recommended by the Centers for Disease Control and Prevention for placement, maintenance, and removal of catheters. Leaders from all critical care disciplines agreed to align routine culturing practice with American College of Critical Care Medicine (ACCCM) and Infectious Disease Society of America (IDSA) guidelines for evaluating a fever in a critically ill patient. Surveillance data for CAUTI and hospital-acquired bloodstream infection (HABSI) were recorded prospectively according to National Healthcare Safety Network (NHSN) protocols. Device utilization ratios (DURs), rates of CAUTI, HABSI, and urine cultures were calculated and compared.
The CAUTI rate decreased from 3.0 per 1,000 catheter days in 2013 to 1.9 in 2014. The DUR was 0.7 in 2013 and 0.68 in 2014. The HABSI rates per 1,000 patient days decreased from 2.8 in 2013 to 2.4 in 2014.
Effectively reducing ICU CAUTI rates requires a multifaceted and collaborative approach; stewardship of culturing was a key and safe component of our successful reduction efforts.
An enhanced understanding of the microstructure of oxide ceramics will help scientists and engineers improve their efficiency and design. A phase-field model for the composition and phase distribution of the oxide ceramic components is studied. The model, which includes an obstacle in the phase portion of the energy potential, results in a minimisation problem that characterises the distribution of the bulk phases. The transition region between them is studied in several mathematically plausible asymptotic limits. The behaviour of the system in these limits provides insights into the applicability of the model and indicates appropriate parameter regimes.
Children with cows' milk protein allergy (CMPA) are at risk of insufficient length and weight gain, and the nutritional efficacy of hypo-allergenic formulas should be carefully assessed. In 2008, a trial assessed the impact of probiotic supplementation of an extensively hydrolysed casein-based formula (eHCF) on acquisition of tolerance in 119 infants with CMPA. First analysis of the study results showed that the studied formula allowed improvement of food-related symptoms. The scoring of atopic dermatitis (SCORAD) index was assessed at randomisation and after 6 months of feeding. A post hoc analysis was performed using WHO growth software's nutritional survey module (WHO Anthro version 3.2.2). All infants who were fed the study formula tolerated it well. The SCORAD index significantly improved from randomisation to 6 months of feeding with the study formula. Anthropometric data indicated a significant improvement in the weight-for-age, length-for-age and weight-for-length z scores, as well as in the restoration of normal BMI. The probiotic supplementation did not show any impact on these parameters. The present data showed that this eHCF was clinically tolerated and significantly improved the SCORAD index and growth indices.
In nature, biomolecules guide the formation of hierarchically-ordered, lightweight, inorganic-organic composites such as corals, shells, teeth and bones. M13 bacteriophage has been used to mimic bio-inspired material development due to its rigid, nanoscale rod-like morphology. Liquid-crystalline monolayers of genetically engineered phage have been used to template crystallization of thin layers of inorganic and metallic materials. We have created thin films composed of engineered M13 phage capable of binding inorganic components. We employed both a dip-cast and a drop-cast film fabrication method on both smooth and rough gold, silica and glass casting surfaces to create thin films and 3D structures of various degrees of hierarchical order. We have found the engineered M13 phage and the inorganic mineral significantly affected both film morphology and the mechanical properties of the film. Similarly, film fabrication parameters such as solution chemistry, temperature, and pulling speed affected film properties. Using a calcium phosphate biomineralized 4E phage, film thickness increased linearly with the number of layers/dips in the phage solution. The stiffness of these composites (Young's modulus) were >80 GPa for mineralized, multilayer films. These materials are an order of magnitude stiffer than the biological equivalent collagen. Stiffness, however, does not appear to increase in a multilayer film beyond a saturation point. Ultimately, we have developed a platform for phage-based bio-composites for developing high performance materials.
Designing new materials with well-defined structures and desired functions is a challenge in materials science, especially with nanomaterials. Nature, however, solves design of these materials through a self-assembling, hierarchically ordered process. We have investigated the mechanisms by which the high- aspect ratio and unique surface chemistry of M13 bacteriophage can give rise to increasingly complex, hierarchically ordered, bundled phage structures with a wide range of material applications. A molecular dynamic simulation of the 3-D structure of a 20-nm section of wild type (WT) and mutant phage types were developed based on WT phage crystal structure and ab initio calculations. Simulations of these phage were then used to examine repulsive and attractive forces of the particles in solution. Examination of contact interactions between two WT phage indicated the phage were maximally attracted to each other in a head to tail orientation. A mutant phage (4E) with a higher negative surface charge relative to WT phage also preferentially ordered head to tail in solution. In contrast, a mutant phage (CLP8) with a net positive surface charge had minimal repulsion in a 90° orientation. Understanding the self-assembly process through molecular dynamic simulations and decomposition of fundamental forces driving inter- and intra-strand interactions has provided a qualitative assessment of mechanisms that lead to hierarchical phage bundle structures. Results from simulation agree with experimentally observed patterns from self-assembly. We anticipate using this system to further investigate development of hierarchical structures not only from biological molecules but also from synthetic materials.