Lifetime Assessment of Load-Bearing Polymer Glasses: The Influence of Physical Ageing

The timescale at which ductile failure occurs in loaded glassy polymers can be successfully predicted using the engineering approach presented in a previous publication. In this paper the influence of progressive physical ageing on the plastic deformation behaviour of unplasticised poly(vinyl chloride) (uPVC) is characterised and incorporated in the existing approach. With the modification it is possible to quantitatively predict long-term failures which show a so-called endurance limit. The predictions are compared with failure data of uPVC specimens which were subjected to constant or dynamic loads. In dynamic loading conditions a second type of failure mode was observed: fatigue crack growth. A brief study on the influence of the frequency and stress ratio of the applied stress signal shows that crack growth failure is not expected to occur within experimentally reasonable timescales for constant loading conditions

Cranial ultrasound findings in preterm germinal matrix haemorrhage, sequelae and outcome

Germinal matrix-intraventricular haemorrhage (GMH-IVH), periventricular haemorrhagic infarction (PHI) and its complication, post-haemorrhagic ventricular dilatation (PHVD), are still common neonatal morbidities in preterm infants that are highly associated with adverse neurodevelopmental outcome. Typical cranial ultrasound (CUS) findings of GMH-IVH, PHI and PHVD, their anatomical substrates and underlying mechanisms are discussed in this paper. Furthermore, we propose a detailed descriptive classification of GMH-IVH and PHI that may improve quality of CUS reporting and prediction of outcome in infants suffering from GMH-IVH/PHI

Pygmy dipole strength close to particle-separation energies - the case of the Mo isotopes

The distribution of electromagnetic dipole strength in 92, 98, 100 Mo has been investigated by photon scattering using bremsstrahlung from the new ELBE facility. The experimental data for well separated nuclear resonances indicate a transition from a regular to a chaotic behaviour above 4 MeV of excitation energy. As the strength distributions follow a Porter-Thomas distribution much of the dipole strength is found in weak and in unresolved resonances appearing as fluctuating cross section. An analysis of this quasi-continuum - here applied to nuclear resonance fluorescence in a novel way - delivers dipole strength functions, which are combining smoothly to those obtained from (g,n)-data. Enhancements at 6.5 MeV and at ~9 MeV are linked to the pygmy dipole resonances postulated to occur in heavy nuclei.Comment: 6 pages, 5 figures, proceedings Nuclear Physics in Astrophysics II, May 16-20, Debrecen, Hungary. The original publication is available at www.eurphysj.or

Nuclear medicine imaging of posttraumatic osteomyelitis

Early recognition of a possible infection and therefore a prompt and accurate diagnostic strategy is essential for a successful treatment of posttraumatic osteomyelitis (PTO). However, at this moment there is no single routine test available that can detect osteomyelitis beyond doubt and the performed diagnostic tests mostly depend on personal experience, available techniques and financial aspects. Nuclear medicine techniques focus on imaging pathophysiological changes which usually precede anatomical changes. Together with recent development in hybrid camera systems, leading to better spatial resolution and quantification possibilities, this provides new opportunities and possibilities for nuclear medicine modalities to play an important role in diagnosing PTO. In this overview paper the techniques and available literature results for PTO are discussed for the three most commonly used nuclear medicine techniques: the three phase bone scan (with SPECT-CT), white blood cell scintigraphy (also called leukocyte scan) with SPECT-CT and F-18-fluorodeoxyglucose (FDG)-PET/CT. Emphasis is on how these techniques are able to answer the diagnostic questions from the clinicians (trauma and orthopaedic surgeons) and which technique should be used to answer a specific question. Furthermore, three illustrative cases from clinical practice are described

The Antifungal Plant Defensin HsAFP1 from Heuchera sanguinea Induces Apoptosis in Candida albicans

Plant defensins are active against plant and human pathogenic fungi (such as Candida albicans) and baker's yeast. However, they are non-toxic to human cells, providing a possible source for treatment of fungal infections. In this study, we characterized the mode of action of the antifungal plant defensin HsAFP1 from coral bells by screening the Saccharomyces cerevisiae deletion mutant library for mutants with altered HsAFP1 sensitivity and verified the obtained genetic data by biochemical assays in S. cerevisiae and C. albicans. We identified 84 genes, which when deleted conferred at least fourfold hypersensitivity or resistance to HsAFP1. A considerable part of these genes were found to be implicated in mitochondrial functionality. In line, sodium azide, which blocks the respiratory electron transport chain, antagonized HsAFP1 antifungal activity, suggesting that a functional respiratory chain is indispensable for HsAFP1 antifungal action. Since mitochondria are the main source of cellular reactive oxygen species (ROS), we investigated the ROS-inducing nature of HsAFP1. We showed that HsAFP1 treatment of C. albicans resulted in ROS accumulation. As ROS accumulation is one of the phenotypic markers of apoptosis in yeast, we could further demonstrate that HsAFP1 induced apoptosis in C. albicans. These data provide novel mechanistic insights in the mode of action of a plant defensin

High delayed and missed injury rate after inter-hospital transfer of severely injured trauma patients

PURPOSE: Missed injuries are reported in 1.3-65% of all admitted trauma patients. The severely injured patient that needs a higher level of care which requires an inter-hospital transfer has an increased risk for missed injuries. The aim of this study was to establish the incidence and clinical relevance of missed injuries in severely injured patients who require inter-hospital transfer to a level 1 trauma center. METHODS: All patients with an Injury Severity Score (ISS) ≥ 16 transferred to the University Medical Center Groningen (UMCG) between January 2010 and July 2015 were included. Data were obtained from a prospective trauma database and supplemented with information from the patient records. A delayed diagnosis was defined as any injury detected within the first 24 h after the initial trauma, with or without a tertiary survey. Missed diagnoses were defined as any injury diagnosed after 24 h following trauma. RESULTS: Two hundred and fifty-one trauma patients were included. A total of 88 patients (35%) were found to have ≥ 1 new diagnoses with 65 (26%) patients that had 1 or more delayed diagnoses and 23 (9.2%) patients had 1 or more missed diagnoses (detected > 24 h after injury) after transfer to our hospital. For 47 of the 88 patients (53%), the new diagnoses required a change of management. The Glasgow Coma Scale (GCS) was the only statistically significant risk factor for a new diagnosis upon transfer. CONCLUSIONS: Inter-hospital transfer of severely injured patients increases the risk of a delayed detection of injuries. We found that 35% of all transferred patients with an ISS ≥ 16 have at least new diagnoses, with over half of these diagnoses requiring a change of management. Given these findings, clinicians should maintain a high index of suspicion when receiving a transferred severely injured trauma patient