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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.
Patients with schizophrenia suffer from a broad range of cognitive disturbances. The impact in terms of functional outcome is significant. There are also several reports of disturbed autonomic regulation in the disease. The present study examined cognitive function as well as psychophysiological parameters in patients with schizophrenia and healthy controls.
Twenty-five patients and 14 controls were investigated with electrodermal activity (EDA), an oral niacin skin flush test and a comprehensive neurocognitive test program including the Wechsler battery (WAIS-R), Fingertapping Test, Trail Making Test, Verbal Fluency, Benton Visual Retention Test, Wisconsin Card Sorting Test and Rey Auditory Verbal Learning Test.
The patients generally had inferior test results compared to controls. Further analysis revealed that the EDA non-responding patient group explained this variation with significant lower test results than controls. On executive tests, EDA non-responders also performed significantly worse than EDA responding patients. The small group of niacin non-responding patients exhibited an even lower overall test performance. Delayed niacin flush also correlated inversely with psychomotor function and IQ in the patients.
The findings support the hypothesis of a neurodevelopment disturbance affecting both autonomic function and higher cortical function in schizophrenia.
Antimicrobial resistance (AMR) is a global public health threat. Emergence of AMR occurs naturally, but can also be selected for by antimicrobial exposure in clinical and veterinary medicine. Despite growing worldwide attention to AMR, there are substantial limitations in our understanding of the burden, distribution and determinants of AMR at the population level. We highlight the importance of population-based approaches to assess the association between antimicrobial use and AMR in humans and animals. Such approaches are needed to improve our understanding of the development and spread of AMR in order to inform strategies for the prevention, detection and management of AMR, and to support the sustainable use of antimicrobials in healthcare.
The use of underground geological repositories, such as in radioactive waste disposal (RWD) and in carbon capture (widely known as Carbon Capture and Storage; CCS), constitutes a key environmental priority for the 21st century. Based on the identification of key scientific questions relating to the geophysics, geochemistry and geobiology of geodisposal of wastes, this paper describes the possibility of technology transfer from high-technology areas of the space exploration sector, including astrobiology, planetary sciences, astronomy, and also particle and nuclear physics, into geodisposal. Synergies exist between high technology used in the space sector and in the characterization of underground environments such as repositories, because of common objectives with respect to instrument miniaturization, low power requirements, durability under extreme conditions (in temperature and mechanical loads) and operation in remote or otherwise difficult to access environments.
Individuals with major depressive disorder (MDD) are characterized by maladaptive responses to both positive and negative outcomes, which have been linked to localized abnormal activations in cortical and striatal brain regions. However, the exact neural circuitry implicated in such abnormalities remains largely unexplored.
In this study 26 unmedicated adults with MDD and 29 matched healthy controls (HCs) completed a monetary incentive delay task during functional magnetic resonance imaging (fMRI). Psychophysiological interaction (PPI) analyses probed group differences in connectivity separately in response to positive and negative outcomes (i.e. monetary gains and penalties).
Relative to HCs, MDD subjects displayed decreased connectivity between the caudate and dorsal anterior cingulate cortex (dACC) in response to monetary gains, yet increased connectivity between the caudate and a different, more rostral, dACC subregion in response to monetary penalties. Moreover, exploratory analyses of 14 MDD patients who completed a 12-week, double-blind, placebo-controlled clinical trial after the baseline fMRI scans indicated that a more normative pattern of cortico-striatal connectivity pre-treatment was associated with greater improvement in symptoms 12 weeks later.
These results identify the caudate as a region with dissociable incentive-dependent dACC connectivity abnormalities in MDD, and provide initial evidence that cortico-striatal circuitry may play a role in MDD treatment response. Given the role of cortico-striatal circuitry in encoding action–outcome contingencies, such dysregulated connectivity may relate to the prominent disruptions in goal-directed behavior that characterize MDD.
Multi-locus variable number tandem repeat analysis (MLVA) is used in clinical and reference laboratories for subtyping verocytotoxin-producing Escherichia coli O157 (VTEC O157). However, as yet there is no common allelic or profile nomenclature to enable laboratories to easily compare data. In this study, we carried out an inter-laboratory comparison of an eight-loci MLVA scheme using a set of 67 isolates of VTEC O157. We found all but two isolates were identical in profile in the two laboratories, and repeat units were homogeneous in size but some were incomplete. A subset of the isolates (n = 17) were sequenced to determine the actual copy number of representative alleles, thereby enabling alleles to be named according to international consensus guidelines. This work has enabled us to realize the potential of MLVA as a portable, highly discriminatory and convenient subtyping method.
Nitric oxide (NO) release can promote healthy tissue regeneration. A PEG-fibrinogen adhesive hydrogel that would allow for inducible NO release was created with mechanical properties that could be tailored to specific applications and tissue types. PEG (4-arm)-fibrinogen hydrogels of varying ratios were derivatized with S-nitroso-N-acetyl-D, L-penicillamine (SNAP)-thiolactone to create an active NO donor material. Controlled release from gels was established using light as the activating source, although temperature, pH, and external mechanical loading are also means to induce active NO release. Gels with varying ratios of fibrinogen to PEG were made, derivatized, and tested. Gels below a ratio of 1.5:1 (fibrinogen:PEG) did not gel, while at ratio of 1.5:1 gelation occurs and NO release can be induced. Interestingly, the release from 1.5:1 gels was significantly lower compared to 2:1 and 3:1 gel formulations. Rheometric data show that lower ratio gels are more elastic than viscous. Derivatized gels exhibited linear elastic moduli, behaving more like other more synthetic hydrogels. Swelling data indicates that as the ratio of fibrinogen to PEG increases the swelling ratio decreases, likely due to the hydrophobic nature of the NO donor. Cells remain viable on both derivatized and non-derivatized gels.
The subcritical flow of a stream over a bottom obstruction or depression is considered with particular interest in obtaining solutions with no downstream waves. In the linearised problem this can always be achieved by superposition of multiple obstructions, but it is not clear whether this is possible in a full nonlinear problem. Solutions computed here indicate that there is an effective nonlinear superposition principle at work as no special shape modifications were required to obtain wave-cancelling solutions. Waveless solutions corresponding to one or more trapped waves are computed at a range of different Froude numbers and are shown to provide a rather elaborate mosaic of solution curves in parameter space when both negative and positive obstruction heights are included.
Norovirus (NoV) is a leading cause of outbreaks of gastroenteritis worldwide, and a major burden for healthcare facilities. This study investigated the NoV genotypes responsible for outbreaks in Edinburgh healthcare facilities between June 2008 and July 2011, and studied their temporal distribution to enable a better understanding of the epidemiology of the outbreaks. A total of 287 samples positive for NoV genogroup II (GII) RNA by reverse transcription–polymerase chain reaction (RT–PCR) during routine diagnostic testing were investigated. Nested RT–PCR (nRT–PCR) and sequencing was used to genotype the NoV strains. Overall, a total of 69 NoV strains belonging to six different genoclusters (GII.1, GII.2, GII.3, GII.4, GII.6, GII.13) were detected. The predominant genotype was GII.4 that included four variants, GII.4 2006a, GII.4 2006b, GII.4 2007 and GII.4 2010. Importantly, increases in NoV activity coincided with the emergence of new GII.4 strains, highlighting the need for an active surveillance system to allow the rapid identification of new strains.
Coronary artery disease is a major problem worldwide causing 7.2 million deaths worldwide annually, resulting from vascular occlusion, myocardial infarction and its complications. Stent implantation is a percutaneous interventional procedure that mitigates vessel stenosis, providing mechanical support within the artery. However, stenting causes physical damage to the arterial wall. It is well accepted that a valuable route to reduce in-stent re-stenosis can be based on promoting cell response to nano-structured stainless steel (SS) surfaces such as, for example, by patterning nano-pits in SS. In this regard patterning by Focussed Ion-Beam (FIB) milling offers several advantages for flexible prototyping (i) practically any substrate material that is able to withstand high vacuum conditions of the microscope chamber can be used, (ii) there is high flexibility in the obtainable shapes and geometries by modulating the ion beam current and the patterning conditions, (iii) reduced complexity of the pattering process e.g. it is a single-step process with a possibility of real-time monitoring of the milling progression. On the other hand FIB patterning of polycrystalline metals is greatly influenced by channelling effects and re-deposition. Correlative microscopy methods present an opportunity to study such effects comprehensively and derive structure-property understanding that is important for developing improved pattering. In this report we present a FIB patterning protocol for nano-structuring features (concaves) ordered in rectangular arrays on pre-polished 316L Stainless Steel (SS) surfaces. An investigation based on correlative microscopy approach of the size, shape and depth of the developed arrays in relation to the crystal orientation of the underlying SS domains, is presented. The correlative microscopy protocol is based on cross-correlation of top-view Scanning Electron Microscopy (SEM), Electron Backscattered Diffraction (EBSD), and Atomic Force Microscopy (AFM).Various dose tests were performed, aiming at improved productivity by preserving nano-size accuracy of the patterned process. The optimal FIB patterning conditions for achieving reasonably high throughput (patterned rate of about 0.03 mm2 per hour) and nano-size accuracy in dimensions and shapes of the features, are discussed as well.