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Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Necrotising enterocolitis (NEC) is a devastating disease that typically affects formula-fed premature infants, suggesting that dietary components may influence disease pathogenesis. TAG are the major fat components of infant formula, and their digestion requires pancreatic lipases, which may be naturally deficient in premature neonates. We hypothesise that NEC develops partly from the accumulation of incompletely digested long-chain TAG-containing unsaturated fatty acids within the intestinal epithelial cells, leading to oxidative stress and enterocyte damage. We further hypothesise that the administration of a formula that contains reduced TAG (‘pre-digested fat’) that do not require lipase action may reduce NEC severity. To test these hypotheses, we induced NEC in neonatal mice using three different fat formulations, namely ‘standard fat’, ‘pre-digested fat’ or ‘very low fat’, and determined that mice fed ‘standard fat’ developed severe NEC, which was significantly reduced in mice fed ‘pre-digested fat’ or ‘very low fat’. The expression level of the critical fat-digesting enzyme carboxyl ester lipase was significantly lower in the newborn compared with older pups, leading to impaired fat digestion. The accumulation of mal-digested fat resulted in the significant accumulation of fat droplets within the intestinal epithelium of the distal ileum, resulting in the generation of reactive oxygen species and intestinal inflammation. Strikingly, these changes were prevented in pups fed ‘pre-digested fat’ or ‘very low fat’ formulas. These findings suggest that nutritional formula containing a pre-digested fat system may overcome the natural lipase deficiency of the premature gut, and serve as a novel approach to prevent NEC.
Respecting a person’s choices about the mental health services they do or do not use is a mark of quality support, and is often pursued for moral reasons, as a rights imperative and to improve outcomes. Yet, providing information and assistance for people making decisions about the mental health services can be a complex process, and has been approached in various ways. Two prominent approaches to this end are ‘shared decision-making’ and ‘supported decision-making’. This article considers each of these approaches, discussing points of similarity and difference and considering how the two might complement one another. By exploring the contribution that each approach can make, we conclude by proposing how future application of these approaches can account for the broader context of decisions, including support for ongoing decision-making; the multitude of service settings where decision-making occurs; and the diversity in supportive practices required to promote active involvement.
Based on seven measured sections from Svalbard, the marine strata of the Permian Kapp Starostin Formation are arranged into seven transgressive–regressive sequences (TR1–TR7) of c. 4–5 Ma average duration, each bound by a maximum regressive surface. Facies, including heterozoan-dominated limestones, spiculitic cherts, sandstones, siltstones and shales, record deposition within inner, middle and outer shelf areas. The lowermost sequence, TR1, comprises most of the basal Vøringen Member, which records a transgression across the Gipshuken Formation following a hiatus of unknown duration. Temperate to cold, storm-dominated facies established in inner to middle shelf areas between the latest Artinskian and Kungurian. Prolonged deepening during sequences TR2 and TR3 was succeeded by a long-term shallowing-upward trend that lasted until the latest Permian (TR4–TR7). A major depocentre existed in central and western Spitsbergen while to the north, Dickson Land remained a shallow platform, leading to a shallow homoclinal ramp in NE Spitsbergen and Nordaustlandet. The Middle Permian extinction (late Capitanian) is recorded near the base of TR6 in deeper parts of the basin only; elsewhere this sequence is not recorded. Likewise the youngest sequence, TR7, extending to the upper formational contact of latest Permian age, is found only in the basin depocentre. Comparison with age-equivalent strata in the Sverdrup Basin of Canada reveals a remarkably similar depositional history, with, for example, two (third-order) sea-level cycles recorded in the Late Permian of both regions, in keeping with the global record. Sequence stratigraphy may therefore be a powerful correlative tool for onshore and offshore Permian deposits across NW Pangaea.
Necrotising enterocolitis (NEC) is a common disease in premature infants characterised by intestinal ischaemia and necrosis. The only effective preventative strategy against NEC is the administration of breast milk, although the protective mechanisms remain unknown. We hypothesise that an abundant human milk oligosaccharide (HMO) in breast milk, 2′-fucosyllactose (2′FL), protects against NEC by enhancing intestinal mucosal blood flow, and we sought to determine the mechanisms underlying this protection. Administration of HMO-2′FL protected against NEC in neonatal wild-type mice, resulted in a decrease in pro-inflammatory markers and preserved the small intestinal mucosal architecture. These protective effects occurred via restoration of intestinal perfusion through up-regulation of the vasodilatory molecule endothelial nitric oxide synthase (eNOS), as administration of HMO-2′FL to eNOS-deficient mice or to mice that received eNOS inhibitors did not protect against NEC, and by 16S analysis HMO-2′FL affected the microbiota of the neonatal mouse gut, although these changes do not seem to be the primary mechanism of protection. Induction of eNOS by HMO-2′FL was also observed in cultured endothelial cells, providing a link between eNOS and HMO in the endothelium. These data demonstrate that HMO-2′FL protects against NEC in part through maintaining mesenteric perfusion via increased eNOS expression, and suggest that the 2′FL found in human milk may be mediating some of the protective benefits of breast milk in the clinical setting against NEC.
Flowering and successful pollination in wheat are key determinants of both quantity and quality of grain. Bread wheat line ‘Paragon’, introgressed with single or multiple daylength insensitivity alleles was used to dissect the effects on the timing and duration of flowering within a hierarchical plant architecture. Flowering of wheat plants was observed in a series of pot-based and field experiments. Ppd-D1a was the most potent known allele affecting the timing of flowering, requiring the least thermal time to flowering across all experiments. The duration of flowering for individual lines was dominated by the shift in the start of flowering in later tillers and the number of tillers per plant, rather than variation in flowering duration of individual spikes. There was a strong relationship between flowering duration and the start of flowering with the earliest lines flowering for the longest. The greatest flowering overlap between tillers was recorded for the Ppd-1b. Across all lines, a warmer environment significantly reduced the duration of flowering and the influence of Ppd-1a alleles on the start of flowering. These findings provide evidence of pleiotropic effects of the Ppd-1a alleles, and have direct implications for breeding for increased stress resilient wheat varieties.
Coral reef ecosystems have great importance for the countries of the Wider Caribbean Region in terms of both use and non-use values and services. Several of the contributors to this symposium attest to their importance for fisheries and biodiversity (see Ehrhardt et al. in Chapter 11; Appeldoorn in Chapter 10; Appeldoorn et al. in Chapter 12; Horrocks et al. in Chapter 9). Coral reef ecosystems support livelihoods (see McConney and Salas in Chapter 7) and provide critical ecosystem services (Schuhmann et al. in Chapter 8) including for tourism, although this aspect of their value is not developed in detail in Chapter 8. Caribbean coral reef ecosystems have been degraded by many human impacts of both marine and land-based origin (see Sweeney and Corbin in Chapter 4; Gil and Wells in Chapter 5; Yáñez-Arancibia et al. in Chapter 17). They are among the most complex and biologically diverse marine ecosystems, and will require a holistic ecosystem- based approach for their conservation and sustainable use.
This synthesis chapter presents the outputs of a group process aimed at developing a vision and way ahead for ecosystem-based management (EBM) for coral reef ecosystems in the Wider Caribbean, using the methods described earlier (Fanning et al. in Chapter 1). The chapter first describes a vision for coral reef EBM and reports on the priorities assigned to the identified vision elements. It then discusses how the vision might be achieved by taking into account assisting factors (those that facilitate achievement) and resisting factors (those that inhibit achievement). The chapter concludes with guidance on the strategic direction needed to implement the vision, identifying specific actions to be undertaken for each of the vision elements.
The occupational breakdown of members of the Coral Reef Ecosystems Working Group reflected the diversity of affiliations present at the EBM Symposium and included governmental, intergovernmental, academic, non-governmental and private sector (fishers and fishing industry and consulting) representatives. With guidance provided by the facilitator, this diverse group of participants was asked to first address the question of “What do you see in place in 10 years’ time when EBM/EAF has become a reality in the Caribbean?”
In an outbreak of gastroenteritis on board a cruise ship 251 passengers and 51 crew were affected and consulted the ship's surgeon during a 14-day period. There was a significant association between consumption of cabin tap water and reported illness in passengers. Enterotoxigenic Escherichia coli were isolated from passengers and crew and coliforms were found in the main water storage tank. Contamination of inadequately chlorinated water by sewage was the most likely source of infection.
A low level of reported illness and late recognition of the outbreak delayed investigation of what was probably the latest in a series of outbreaks of gastrointestinal illness on board this ship. There is a need for a national surveillance programme which would monitor the extent of illness on board passenger cruise ships as well as a standard approach to the action taken when levels of reported illness rise above a defined level.
Fibroblast growth factor (FGF)-2 (basic) is a potent angiogenic molecule involved in tumor progression, and is one of several growth factors with a central role in ovarian carcinogenesis. We hypothesized that common single nucleotide polymorphisms (SNPs) in the FGF2 gene may alter angiogenic potential and thereby susceptibility to ovarian cancer. We analyzed 25 FGF2 tgSNPs using five independent study populations from the United States and Australia. Analysis was restricted to non-Hispanic White women with serous ovarian carcinoma (1269 cases and 2829 controls). There were no statistically significant associations between any FGF2 SNPs and ovarian cancer risk. There were two nominally statistically significant associations between heterozygosity for two FGF2 SNPs (rs308379 and rs308447; p < .05) and serous ovarian cancer risk in the combined dataset, but rare homozygous estimates did not achieve statistical significance, nor were they consistent with the log additive model of inheritance. Overall genetic variation in FGF2 does not appear to play a role in susceptibility to ovarian cancer.
This study focuses on fracture properties of silicon wafers used by the photovoltaic (PV) industry as substrates for solar cells. In the first part, we numerically model three fixtures that are often used to test the strength of PV wafers. In the second part, we employ our previously developed model to predict strength of the wafers as a function of loading fixture and surface treatment. Surface treatment is simulated by removing damage from the wafer surface.
While the low thermal conductivities of silica aerogels have made them of interest to the aerospace community as lightweight thermal insulation, the application of conformal polymer coatings to these gels increases their strength significantly, making them potentially useful as structural materials as well. In this work we perform multiscale computer simulations to investigate the tensile and compressive strain behavior of silica and polymer-coated silica aerogels.
Aerogels are made up of clusters of interconnected particles of amorphous silica of less than bulk density. We simulate gel nanostructure using a Diffusion Limited Cluster Aggregation (DLCA) procedure, which produces aggregates that exhibit fractal dimensions similar to those observed in real aerogels. We have previously found that model gels obtained via DLCA exhibited stress-strain curves characteristic of the experimentally observed brittle failure. However, the strain energetics near the expected point of failure were not consistent with such failure. This shortcoming may be due to the fact that the DLCA process produces model gels that are lacking in closed-loop substructures, compared with real gels. Our model gels therefore contain an excess of dangling strands, which tend to unravel under tensile strain, producing non-brittle failure. To address this problem, we have incorporated a modification to the DLCA algorithm that specifically produces closed loops in the model gels.
We obtain the strain energetics of interparticle connections via atomistic molecular statics, and abstract the collective energy of the atomic bonds into a Morse potential scaled to describe gel particle interactions. Polymer coatings are similarly described.
We apply repeated small uniaxial strains to DLCA clusters, and allow relaxation of the center eighty percent of the cluster between strains. The simulations produce energetics and stress-strain curves for looped and nonlooped clusters, for a variety of densities and interaction parameters.
The NASA Star and Exoplanet Database (NStED) is a general purpose stellar archive with the aim of providing support for NASA's planet finding and characterization goals, stellar astrophysics, and the planning of NASA and other space missions. There are two principal components of NStED: a database of (currently) 140,000 nearby stars and exoplanet-hosting stars, and an archive dedicated to high precision photometric surveys for transiting exoplanets. We present a summary of the NStED stellar database, functionality, tools, and user interface. NStED currently serves the following kinds of data for 140,000 stars (where available): coordinates, multiplicity, proper motion, parallax, spectral type, multiband photometry, radial velocity, metallicity, chromospheric and coronal activity index, and rotation velocity/period. Furthermore, the following derived quantities are given wherever possible: distance, effective temperature, mass, radius, luminosity, space motions, and physical/angular dimensions of habitable zone. Queries to NStED can be made using constraints on any combination of the above parameters. In addition, NStED provides tools to derive specific inferred quantities for the stars in the database, cross-referenced with available extra-solar planetary data for those host stars. NStED can be accessed at http://nsted.ipac.caltech.edu.
The NASA Star and Exoplanet Database (NStED) is a general purpose stellar archive with the aim of providing support for NASA's planet finding and characterization goals, stellar astrophysics, and the planning of NASA and other space missions. There are two principal components of NStED: a database of (currently) 140,000 nearby stars and exoplanet-hosting stars, and an archive dedicated to high-precision photometric surveys for transiting exoplanets. We present a summary of the latter component: the NStED Exoplanet Transit Survey Service (NStED-ETSS), along with its content, functionality, tools, and user interface. NStED-ETSS currently serves data from the TrES Survey of the Kepler Field as well as dedicated photometric surveys of four stellar clusters. NStED-ETSS aims to serve both the surveys and the broader astronomical community by archiving these data and making them available in a homogeneous format. Examples of usability of ETSS include investigation of any time-variable phenomena in data sets not studied by the original survey team, application of different techniques or algorithms for planet transit detections, combination of data from different surveys for given objects, statistical studies, etc. NStED-ETSS can be accessed at http://nsted.ipac.caltech.edu.
A recent study at this Centre has shown that maize silage, regardless of maturity at harvest has the same feed value as grass silage when offered to ewes in late pregnancy (Keady and Hanrahan 2008). The control of gastrointestinal nematodes of sheep is largely dependent on the use of anthelmintics. The increasing evidence for resistance to nematode parasites of sheep to the broad-spectrum anthelmintics (Good, 2005; Good et al., 2007) has led to the search for alternative sustainable solutions to parasite control. The temporary loss of acquired immunity to gastrointestinal nematodes that is indicated by an increased faecal egg output in late pregnancy and early lactation is a well established phenomenon and is important in the epidemiology of nematodes parasites of sheep. There is substantial evidence for nutritional effects on the expression of immunity to gastrointestinal nematodes. In particular, there is evidence that faecal egg output of parasitised periparturient ewes is reduced in response to increased dietary metabolizable protein (Coop & Kyriazakis 1999; Donaldson et al., 1998; Houdijk et al., 2000). The objective of the present study was to evaluate the effect of diet during mid and late pregnancy as influenced by forage type and harvest system, concentrate feed level and soyabean supplementation on the peri-parturient rise in nematode egg output in ewes.