Curvature stabilized skyrmions with angular momentum

We examine skyrmionic field configurations on a spherical ferromagnet with large normal anisotropy. Exploiting variational concepts of angular momentum we find a new family of localized solutions to the Landau-Lifshitz equation that are topologically distinct from the ground state and not equivariant. Significantly, we observe an emergent spin-orbit coupling on the level of magnetization dynamics in a simple system without individual rotational invariance in spin and coordinate space

Mechanical behaviour of sand stabilised with colloidal silica

The response of sand stabilised with colloidal silica aqueous gel is examined in the laboratory, under direct shear, triaxial and normal compression loading, in comparison to that of untreated sand of similar density to evaluate the effect of stabilisation on subsequent sand response. The behaviour of the treated sand differs in important respects from the behaviour of the untreated sand: a significant increase in the angle of shearing resistance is observed at lower stress levels, diminishing with increasing stress level; the peak strength envelope is curved at low stresses for the treated sand only, while at ultimate strength, the envelopes coincide for treated and untreated sands. However, at all stress levels, extreme dilation is associated with the treated sand at peak and ultimate strength conditions. Under normal compression, the treated sand is easily densified, exhibiting higher compressibility than that of sand of similar density. It appears that depending on loading conditions, the aqueous gel alters its structure and has the capacity to absorb or discharge free water; it is of paramount importance to measure volume change and/or pore water pressure change during stabilised sand testing

An interactive data visualisation application to investigate nosocomial transmission of infections

Background: Healthcare-associated infections represent a major threat to patient, staff and visitor safety. Identification of episodes that are likely to have resulted from nosocomial transmission has important implications for infection control. Routinely collected data on ward admissions and sample dates, combined with pathogen genomic information could provide useful insights. We describe a novel, open-source, application for visualising these data, and demonstrate its utility for investigating nosocomial transmission using a case study of a large outbreak of norovirus infection. Methods: We developed the application using Shiny, a web application framework for R. For the norovirus case study, cases were defined as patients who had a faecal sample collected at the hospital in a winter season that tested positive for norovirus. Patient demographics and ward admission dates were extracted from hospital systems. Detected norovirus strains were genotyped and further characterised through sequencing of the hypervariable P2 domain. The most commonly detected sub-strain was visualised using the interactive application. Results: There were 156 norovirus-positive specimens collected from 107 patients. The most commonly detected sub-strain affected 30 patients in five wards. We used the interactive application to produce three visualisations: a bar chart, a timeline, and a schematic ward plan highlighting plausible transmission links. Visualisations showed credible links between cases on the elderly care ward. Conclusions: Use of the interactive application provided insights into transmission in this large nosocomial outbreak of norovirus, highlighting where infection control practices worked well or could be improved. This is a flexible tool that could be used for investigation of any infection in any hospital by interactively changing parameters. Challenges include integration with hospital systems for extracting data. Prospective use of this application could inform better infection control in real time.</ns4:p

Transternal repair of a giant Morgagni hernia causing cardiac tamponade in a patient with coexisting severe aortic valve stenosis

<p>Abstract</p> <p>Background</p> <p>Foramen of Morgagni hernias have traditionally been repaired by laparotomy, lapascopy or even thoracoscopy. However, the trans-sternal approach should be used when these rare hernias coexist with other cardiac surgical diseases.</p> <p>Case presentation</p> <p>We present the case of a 74 year-old symptomatic male with severe aortic <b>valve </b>stenosis and global respiratory failure due to a giant Morgagni hernia causing additionally cardiac tamponade. The patient underwent simultaneous repair of the hernia defect and aortic valve replacement under cardiopulmonary bypass. The hernia was repaired through the sternotomy approach, without opening of its content and during cardiopulmonary reperfusion.</p> <p>Conclusions</p> <p>Morgagni hernia can rarely accompany cardiac surgical pathologies. The trans-sternal approach for its management is as effective as other popular reconstructive procedures, <b>unless viscera strangulation and necrosis are suspected</b>. If severe compressive effects to the heart dominate the patient's clinical presentation correction during the cardiopulmonary reperfusion period is mandatory.</p

Thymomectomy plus total thymectomy versus simple thymomectomy for early-stage thymoma without myasthenia gravis: A European Society of Thoracic Surgeons Thymic Working Group Study

OBJECTIVES: Resection of thymic tumours including the removal of both the tumour and the thymus gland (thymothymectomy; TT) is the procedure of choice and is recommended in most relevant articles in the literature. Nevertheless, in recent years, some authors have suggested that resection of the tumour (simple thymomectomy; ST) may suffice from an oncological standpoint in patients with early-stage thymoma who do not have myasthenia gravis (MG) (non-MG). The goal of our study was to compare the short-and long-term outcomes of ST versus TT in non-MG early-stage thymomas using the European Society of Thoracic Surgeons thymic database. METHODS: A total of 498 non-MG patients with pathological stage I thymoma were included in the study. TT was performed in 466 (93.6%) of 498 patients who had surgery with curative intent; ST was done in 32 (6.4%). The completeness of resection, the rate of complications, the 30-day mortality, the overall recurrence and the freedom from recurrence were compared. We performed crude and propensity score-adjusted comparisons by surgical approach (ST vs TT). RESULTS: TT showed the same rate of postoperative complications, 30-day mortality and postoperative length of stay as ST. The 5-year overall survival rate was 89% in the TT group and 55% in the ST group. The 5-year freedom from recurrence was 96% in the TT group and 79% in the ST group. CONCLUSION: Patients with early-stage thymoma without MG who have a TT show significantly better freedom from recurrence than those who have an ST, without an increase in postoperative morbidity rate

An integrated open-coastal biogeochemistry, ecosystem and biodiversity observatory of the eastern Mediterranean – the Cretan Sea component of the POSEIDON system

There is a general scarcity of oceanic observations that concurrently examine air–sea interactions, coastal–open-ocean processes and physical–biogeochemical processes, in appropriate spatiotemporal scales and under continuous, long-term data acquisition schemes. In the Mediterranean Sea, the resulting knowledge gaps and observing challenges increase due to its oligotrophic character, especially in the eastern part of the basin. The oligotrophic open Cretan Sea's biogeochemistry is considered to be representative of a greater Mediterranean area up to 106&thinsp;km2, and understanding its features may be useful on even larger oceanic scales, since the Mediterranean Sea has been considered a miniature model of the global ocean. The spatiotemporal coverage of biogeochemical (BGC) observations in the Cretan Sea has progressively increased over the last decades, especially since the creation of the POSEIDON observing system, which has adopted a multiplatform, multivariable approach, supporting BGC data acquisition. The current POSEIDON system's status includes open and coastal sea fixed platforms, a Ferrybox (FB) system and Bio-Argo autonomous floats that remotely deliver fluorescence as a proxy of chlorophyll-a (Chl-a), O2, pH and pCO2 data, as well as BGC-related physical variables. Since 2010, the list has been further expanded to other BGC (nutrients, vertical particulate matter fluxes), ecosystem and biodiversity (from viruses up to zooplankton) variables, thanks to the addition of sediment traps, frequent research vessel (R/V) visits for seawater–plankton sampling and an acoustic Doppler current profiler (ADCP) delivering information on macrozooplankton–micronekton vertical migration (in the epipelagic to mesopelagic layer). Gliders and drifters are the new (currently under integration to the existing system) platforms, supporting BGC monitoring. Land-based facilities, such as data centres, technical support infrastructure, calibration laboratory and mesocosms, support and give added value to the observatory. The data gathered from these platforms are used to improve the quality of the BGC-ecosystem model predictions, which have recently incorporated atmospheric nutrient deposition processes and assimilation of satellite Chl-a data. Besides addressing open scientific questions at regional and international levels, examples of which are presented, the observatory provides user-oriented services to marine policy makers and the society, and is a technological test bed for new and/or cost-efficient BGC sensor technology and marine equipment. It is part of European and international observing programs, playing a key role in regional data handling and participating in harmonization and best practices procedures. Future expansion plans consider the evolving scientific and society priorities, balanced with sustainable management.</p