Beyond swarm intelligence: The Ultraswarm

This paper explores the idea that it may be possible to combine two ideas – UAV flocking, and wireless cluster computing – in a single system, the UltraSwarm. The possible advantages of such a system are considered, and solutions to some of the technical problems are identified. Initial work on constructing such a system based around miniature electric helicopters is described

The effect of Nystatin on the inner ear : an experimental guinea pig study

Objectifs: Le Nystatin est un antibiotique efficace pour le traitement d’otomycose. Bien que sa sécurité au niveau de l’oreille externe soit bien établie, son utilisation n’est pas recommandée lorsqu’il y a une perforation tympanique. L’objectif de cette étude est d’évaluer le potentiel ototoxique du Nystatin lorsque celui-ci est appliqué directement au niveau de l’oreille moyenne. Méthodes: Nous avons fait une étude expérimentale avec 18 cochons d’Indes de souche Hartley que nous avons divisés en deux groupes. En exposant l’oreille moyenne de chaque animal au Nystatin (groupe I) ou à la néomycine (groupe II) et chaque oreille controlatérale à une solution physiologique (NaCl), la fonction auditive a été évaluée avec un test de potentiels évoqués auditif du tronc cérébral avant et après les injections. Une étude par microscopie électronique a permis une comparaison histologique de l’état des cellules ciliées cochléaires entre les 2 groupes. Résultats: Les pertes auditives moyennes du groupe « Nystatin » étaient de 13.0 dB et comparables aux pertes moyennes observées dans les oreilles ayant été injectées avec du NaCl (4.0 dB dans le groupe I et 15.1 dB dans le groupe II). Le groupe de contrôle « néomycine » a subi une perte auditive moyenne de 39.3 dB, ce qui représente une différence cliniquement et statistiquement significative (p<0.001). L’étude histologique avec une microscopie à balayage électronique a démontré une conservation de l’architecture des cellules ciliées cochléaires dans les groupe Nystatin et NaCl. La néomycine a causé une destruction marquée de ces structures. Conclusions: Le Nystatin ne provoque pas d’atteinte auditive ni de destruction des cellules ciliées externes après injection directe dans l’oreille moyenne chez le cochon d’Inde.Objective: Nystatin is an effective topical antifungal agent widely used in the treatment of otomycosis. Though it is safe for external ear use, current recommendations are to avoid its use in cases of tympanic membrane perforation. The objective of our study was to test the security of Nystatin when applied directly to the middle ear of a guinea pig model. Methods: We performed an experimental study with 18 Hartley guinea pigs that were divided into two groups. Exposing middle ears from one group to Nystatin (group I) and from the other to the ototoxic neomycin (group II), we compared results of auditory brainstem response (ABR) testing at three intervals during the study. Each animal’s contralateral ear was injected with a physiological solution (NaCl). At the end of the study, we performed a histological analysis of the animals’ cochleae using a scanning electron microscope. Results: Average hearing loss in the Nystatin group was 13.0 dB which was similar to the results obtained in the NaCl-exposed ears (4.0 dB in group I and 15.1 dB in group II). Average hearing loss in the neomycin group was 39.3 dB, which represents a clinically significant difference (p<0.001). Scanning electron microscope evaluation revealed intact cochlear hair cell architecture in the Nystatin and normal saline groups, compared to important destruction in the neomycin group. Conclusion: Nystatin does not cause hearing impairment or cochlear hair cell damage when exposed directly to the middle ear of a guinea pig model

A 3D benign paroxysmal positional vertigo model for study of otolith disease

AbstractObjectiveTo develop a three-dimensional study tool of the membranous labyrinth in order to study the pathophysiology, diagnostic workup and treatment of benign paroxysmal positional vertigo (BPPV). BPPV is the most common cause of peripheral vertigo. Its diagnosis and treatment depend on an understanding of the anatomy of the vestibular labyrinth and its position relative to the head. To date, many illustrations have been made to explain principals of diagnosis and treatment of BPPV, but few have been based on anatomical studies of the membranous labyrinth.MethodsA cadaveric human membranous labyrinth was axially sectioned at 20 μm resolution, stained and segmented to create a high-resolution digital model. The model was cloned to create an enantiomeric pair of labyrinths. These were associated a 3D model of a human skull, segmented from MRI data, and were oriented according to established anatomic norms. Canal markers representing otoliths were created to mark canalith position during movement of the model within the 3D environment.ResultsThe model allows visualization of true membranous labyrinth anatomy in both ears simultaneously. The dependent portion of each semicircular duct and of the utricle can easily be visualized in any head position. Moveable markers can mark the expected progress of otolith debris with changes in head position and images can be captured to document simulations. The model can be used to simulate pathology as well as diagnostic maneuvers and treatment procedures used for BPPV. The model has great potential as a teaching tool.ConclusionA simple model based on human anatomy has been created to allow careful study of BPPV pathophysiology and treatment. Going forward, this tool could offer insights that may lead to more accurate diagnosis and treatment of BPPV

An investigation into the impact of microvascular leakage on neutrophil transendothelial migration as analysed using murine models of inflammation.

PhD ThesisControlled opening of endothelial-cell (EC) junctions is vital in regulating vascular permeability and neutrophil transendothelial migration (TEM) during acute inflammation. Although both phenomena can occur independently, as supported by distinct molecular pathways, the potential inter-play of these two responses requires further exploration. In this thesis, we investigated the impact of microvascular leakage on neutrophil TEM and the potential downstream pathophysiological consequences. To this aim, as part of this project, a confocal intravital microscopy platform was developed for simultaneous analysis of neutrophil TEM and vascular permeability within the murine cremaster muscle microcirculation. The inflammatory reactions employed were driven by locally administered LTB4, or IL-1β ± vasoactive agents (e.g. histamine/VEGF), or by a model of IR-injury. The findings provide direct evidence for the ability of inflammatory reactions characterised by enhanced microvascular leakage to promote an aberrant mode of neutrophil TEM, known as reverse (r)TEM. This response is characterised by neutrophils that have partially breached the endothelium and move in a retrograde mode, thus returning into the lumen. Interestingly, genetic functional deficiency or pharmacological blockade of VE-cadherin-dependent hyper-permeability reduced the frequency of neutrophil rTEM. Mechanistically, this migration behaviour was driven by excessive diffusion of tissue-derived CXCL1 through EC junctions into the plasma, resulting in a disrupted chemotactic gradient across the endothelium. Development of a novel tracking method allowed us to demonstrate that rTEM neutrophils exhibited a pro-inflammatory phenotype and disseminated into the blood and lung circulation. Presence of these cells in lungs was associated with vascular damage. Finally, we identified distinct roles for TNF-receptors in controlling vascular permeability and neutrophil migration during IR-injury. Collectively, the findings of this thesis provide a causal link between increased local microvascular leakage induction and disrupted localisation of chemotactic directional cues across the endothelial barrier, resulting in aberrant mode of neutrophil migration and subsequent distant organ damage

Stacking Gravitational Wave Signals from Soft Gamma Repeater Bursts

Soft gamma repeaters (SGRs) have unique properties that make them intriguing targets for gravitational wave (GW) searches. They are nearby, their burst emission mechanism may involve neutron star crust fractures and excitation of quasi-normal modes, and they burst repeatedly and sometimes spectacularly. A recent LIGO search for transient GW from these sources placed upper limits on a set of almost 200 individual SGR bursts. These limits were within the theoretically predicted range of some models. We present a new search strategy which builds upon the method used there by "stacking" potential GW signals from multiple SGR bursts. We assume that variation in the time difference between burst electromagnetic emission and burst GW emission is small relative to the GW signal duration, and we time-align GW excess power time-frequency tilings containing individual burst triggers to their corresponding electromagnetic emissions. Using Monte Carlo simulations, we confirm that gains in GW energy sensitivity of N^{1/2} are possible, where N is the number of stacked SGR bursts. Estimated sensitivities for a mock search for gravitational waves from the 2006 March 29 storm from SGR 1900+14 are also presented, for two GW emission models, "fluence-weighted" and "flat" (unweighted).Comment: 17 pages, 16 figures, submitted to PR

Snaking and isolas of localised states in bistable discrete lattices

We consider localised states in a discrete bistable Allen-Cahn equation. This model equation combines bistability and local cell-to-cell coupling in the simplest possible way. The existence of stable localised states is made possible by pinning to the underlying lattice; they do not exist in the equivalent continuum equation. In particular we address the existence of 'isolas': closed curves of solutions in the bifurcation diagram. Isolas appear for some non-periodic boundary conditions in one spatial dimension but seem to appear generically in two dimensions. We point out how features of the bifurcation diagram in 1D help to explain some (unintuitive) features of the bifurcation diagram in 2D.Comment: 14 page

MASLWR Overview and RELAP5 Simulation

The focus of this presentation is to demonstrate the functionality of the Multi Application Small Light Water Reactor (MASLWR) thermal hydraulic test facility and it’s natural circulation operating behavior as well as analyze the ability of a RELAP5-3D model to simulate this behavior. The MASLWR facility is introduced with a general overview. Test data collected from steady state operation of the natural circulation configuration of the MASLWR facility will be analyzed and compared to a similar RELAP5-3D simulation. The MASLWR Test Facility models the NuScale design of a next generation nuclear power reactor. It is used to provide test data to NuScale which is used to verify their thermal hydraulic codes modeling their own reactor. The primary loop of the MASLWR is fully contained in the RPV. The electrically heater core heats the water at the bottom of the RPV, this hot water rises through the hot leg located centrally in the RPV. At the top of the hot leg the hot water is directed outward and downward to the helical coil steam generator where it is cooled. Once the water is cooled and becomes more dense it then falls down the cold leg and is recirculated into the core. The flow through the primary loop is driven by natural circulation due to the density gradient. In the secondary loop cold water is pumped through the helical coil steam generator. The water boils and exits the coils as steam. Multiple instruments collect data from the steam and then it is vented to atmosphere. The RPV is configured to simulate being located inside a High Pressure Containment (HPC) [1]. The test facility has multiple types of instruments that collect information on pressure drops, temperatures and flow rates in both the primary and secondary loops. Testing has been performed on the MASLWR test facility to analyze the steady state natural circulation in the primary loop. Steady state was achieved at multiple power levels by varying the flow in the secondary loop. At each power level, different flow rates and temperature distributions were observed. This data will serve as a standard for comparison of our RELAP5-3D simulation. Reactor Excursion and Leak Analysis Program 5 (RELAP5) is a thermal-hydraulic safety analysis software package specifically catered to nuclear reactor operations [2]. A RELAP model of the MASLWR test facility has already been built by Dr. Brian Woods and Jordan Bowser of Oregon State University. This model has been modified to fit the parameters of the test data collected. The flow losses built into this model are the most accurate that can be determined with presently available test data, but could be greatly improved with future testing of the MASLWR test facility. The model was run at multiple power levels to determine flow rates required to maintain steady state of the natural circulation system. The RELAP model consists of all components described in the MASLWR test facility overview with a simplified heat removal structure in place of the helical coil steam generator. Steady-state operation of the facility is defined as unchanging conditions in both the primary and secondary systems with respect to time during operation. Data from the MASLWR testing and the RELAP model were compared. The specific paremeters of the most interest are mass flow rate of the primary coolant, and temperature of the coolant at different locations throughout the natural circulation loop. The temperature data from the two sources turned out to be within the tolerances of the testing instruments. The mass flow rate data from the RELAP model underestimated the true data and was outside of the instrument tolerances. In conclusion the inaccuracy of the mass flow rates can be connected to the inaccurate flow losses built into the RELAP model. It is intended that future testing of the MASLWR test facility will be used to determine more accurate flow losses.Keywords: Thermal Hydraulics, MASLWR, Nuclear, Modular Reactor

The effects of inspiratory muscle training on inspiratory muscle strength, lung function and quality of life in adults with spinal cord injuries: A systematic review and Meta-analysis

Purpose: This systematic review and meta-analysis aimed to evaluate the effectiveness of inspiratory muscle training (IMT) on respiratory muscle strength, lung function and quality of life (QOL) in adults with spinal cord injuries (SCI). Methods: Databases were searched up to June 2022; CENTRAL, CINAHL, MEDLINE, PEDRo, and PubMed. Following PRISMA reporting guidelines, two independent reviewers selected studies and extracted data. Study quality and levels of evidence were assessed. Results: Following selection from 624 initial search results, six randomised controlled trials were identified, comprising 124 participants. Quality of Evidence was very low to moderate. Meta-analysis showed that post intervention, IMT significantly improved maximal inspiratory pressure (MD 15.72 cmH2O, 95% CI 5.02, 26.41, p ¼ 0.004) when compared with a control intervention. There was no significant benefit for physical QOL (SMD 0.12, 95% CI 1.01, 1.25, p ¼ 0.84), mental QOL (SMD 0.2, 95% CI 1.72, 1.33, p ¼ 0.80), maximal expiratory pressure (MD 5.19 cmH2O, 95% CI 4.16, 14.55, p ¼ 0.80), or FEV1 (MD 0.26 L, 95% CI 0.19, 0.7, p ¼ 0.26). Sensitivity analyses found larger effects for studies with 8 week interventions (MD 17.5 cmH2O (95% CI 3.36 to 31.66)) and spring loaded devices alone (MD 21.18 cmH2O, 95% CI 9.65 to 32.72). Conclusion: Moderate quality evidence suggests IMT improves respiratory strength in adults with an SCI. The mental and physical QOL outcomes provided very low quality of evidence, with considerable heterogeneity between study results, leading to inconsistency. Further research is warranted to investigate medium and long-term impact of robust IMT protocols, accounting for patient motivation and adherence t

Probiotics: current landscape and future horizons

In recent years there has been a rapid rise in interest for the application of probiotic supplements to act as mediators in health and disease. This appeal is predominantly due to ever-increasing evidence of the interaction of the microbiota and pathophysiological processes of disease within the human host. This narrative review considers the current landscape of the probiotic industry and its research, and discusses current pitfalls in the lack of translation from laboratory science to clinical application. Future considerations into how industry and academia must adapt probiotic research to maximize success are suggested, including more targeted application of probiotic strains dependent on individual capabilities as well as application of multiple advanced analytical technologies to further understand and accelerate microbiome science. Lay abstract: The global market for probiotic supplements is continually expanding. Despite the public perception of benefits provided by probiotics, the evidence to conclusively link probiotic strains to improved characteristics of health or disease is lacking. This is owing, in part, to the lack of large-scale research trials, but also to the insufficient understanding of the interactions occurring within the human system following supplementation. More in-depth research into individual probiotic strains, combined with the application of multiple advanced measurement techniques will provide a future direction for probiotic research and, in turn, aim to provide useful data to translate into routine healthcare practice

Light curves from rapidly rotating neutron stars

We calculate light curves produced by a hot spot of a rapidly rotating neutron star, assuming that the spot is perturbed by a core $r$-mode, which is destabilized by emitting gravitational waves. To calculate light curves, we take account of relativistic effects such as the Doppler boost due to the rapid rotation and light bending assuming the Schwarzschild metric around the neutron star. We assume that the core $r$-modes penetrate to the surface fluid ocean to have sufficiently large amplitudes to disturb the spot. For a $l'=m$ core $r$-mode, the oscillation frequency $\omega\approx2m\Omega/[l'(l'+1)]$ defined in the co-rotating frame of the star will be detected by a distant observer, where $l'$ and $m$ are respectively the spherical harmonic degree and the azimuthal wave number of the mode, and $\Omega$ is the spin frequency of the star. In a linear theory of oscillation, using a parameter $A$ we parametrize the mode amplitudes such that ${\rm max}\left(|\xi_\theta|,|\xi_\phi|\right)/R=A$ at the surface, where $\xi_\theta$ and $\xi_\phi$ are the $\theta$ and $\phi$ components of the displacement vector of the mode and $R$ is the radius of the star. For the $l'=m=2$ $r$-mode with $\omega=2\Omega/3$, we find that the fractional Fourier amplitudes at $\omega=2\Omega/3$ in light curves depend on the angular distance $\theta_s$ of the spot centre measured from the rotation axis and become comparable to or even larger than $A\sim0.001$ for small values of $\theta_s$.Comment: 10 pages, 9 figures, submitted to M