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Background Due to its partially superficial course, the saphenous nerve is vulnerable to injury by trauma or surgery potentially leading to painful neuroma formation. Different surgical techniques to treat neuroma have been described, but so far, no one has proven to be superior to the others. The aim of this study was therefore to identify factors influencing the outcome of revision surgery in saphenous nerve neuropathic pain in our department. Methods From 2010 to 2020, a total of 29 consecutive patients with neuropathic pain and suspected neuroma of the saphenous nerve underwent revision surgery. A medical chart review was performed to collect patient-, pain-, and treatment-specific factors. Outcomes were registered. Results Post revision surgery in neuropathic pain of the saphenous nerve, 16 (55.2%) patients suffered from persisting pain. In multivariable logistic regression models evaluating the risk of persisting pain post saphenous nerve revision surgery, both smoking and preoperative opiate consumption represented independent predictors of higher risk for persisting pain. Conclusions Patients with injury to the saphenous nerve should be coached toward smoking cessation. Whenever possible, forgoing opiate treatment might be beneficial. Level of evidence: Level IV, Risk/Prognostic.

ZusammenfassungIn der peripheren Nervenchirurgie ist die intraoperative Beurteilung eines pathologischen Nervensegmentes von zentraler Bedeutung. Mittels verschiedener Methoden kann die Vitalität eines Nervs beurteilt und zwischen alleiniger Neurolyse oder Resektion und Nervenrekonstruktion entschieden werden. Neben Nervenmorphologie, intraoperativer Schnellschnittdiagnostik und einfacher Nervenstimulation ist die intraoperative Elektrophysiologie ein wertvolles Instrument des Nervenchirurgen. Ziel dieser apparativen Diagnostik ist das Erfassen objektiver Parameter, welche die Funktion peripherer Nerven dokumentieren. Die intraoperative Elektroneurografie erlaubt die Ableitung eines Nervenaktionspotentials über einem pathologisch veränderten Nervensegment und ist seit vielen Jahren etabliert. Im Gegensatz dazu wird die intraoperative Nadel-Elektromyografie in der peripheren Nervenchirurgie noch kaum benutzt, obwohl sie interessante Vorteile mit sich bringt. Sie kann sowohl bei der Selektion geeigneter Faszikel für motorische Neurotisationen als auch bei der Faszikel-topografischen Ableitung von Kontinuitätsneuromen wertvolle Zusatzinformationen generieren. Die vorliegende Übersichtsarbeit fasst die Möglichkeiten der intraoperativen Elektromyografie anhand von Fallbeispielen aus der Traumatologie und Tumorchirurgie zusammen.

This paper reports on the analysis and optimization of high-efficiency organic tandem solar cells via full opto-electronic device simulation on continuum level and using a hopping model for the explicit description of the charge recombination junction. Inclusion of the electrical sub-cell interconnection allows for a rigorous assessment of the impact of the internal charge distribution and associated built-in fields as well as quasi-Fermi level profiles on the measured device characteristics. It enables the direct evaluation of the external quantum efficiency in a simulation that follows closely the measurement protocol, and sheds light on complications related to the dependence of the band profile on the illumination conditions. The study also points at fingerprints of insufficient junction quality in the electrical characteristics of the tandem device. After studying the impact of key electrical parameters such as, carrier mobility, lifetime and interface hopping rate, onto the device characteristics, the latter are optimized not only optically, but also electronically, adding in both cases an increasing number of layers to the parameters of the global optimization procedure. An improvement of 2% absolute power conversion efficiency by using the full opto-electronic optimization as compared to optical optimization only is found.

Complete distal ruptures of the biceps brachii tendon are rather rare and surgical reinsertion is the gold standard. Recently, one incision approaches for the refixation of the distal biceps tendon have been popularized with the introduction of a single-incision approach employing a trans-radial cortical button fixation. Since the introduction of this fixation technique we have seen more iatrogenic lesions to the posterior interosseous nerve (PIN) after not having seen any PIN lesions with 2 incision biceps refixation techniques over the last 5 years. Several patients with iatrogenic PIN affections after one incision refixation techniques of the distal biceps tendon were referred to our level 1 department of Plastic surgery and hand surgery from different orthopedic surgeons. Over the course of 6 months we saw 5 patients with a similar history. We decided to analyze this problem and propose a course of action to regain function of the PIN innervated muscles as good and fast as possible. If there is a loss of function in the PIN innervated muscles after distal biceps refixation a neurological evaluation including electrophysiology needs to be conducted. An ultrasound assessment of the nerve itself should guide the clinician in the decision between a conservative and a surgical treatment in the early postoperative phase. If surgical exploration is warranted intraoperative neurography should be the basis on which ground (partial) grafting or solely neurolysis is performed. Postoperatively all patients need to follow a rehabilitation protocol to help with nerve regeneration and regaining of motor function.

The operational Australian Bluelink ocean forecast system is used to transform physical oceanographic observations into coherent analyses and predictions. These analyses and predictions form the ba...

ZusammenfassungIm Frühstadium von Nervenläsionen stellt die klinische Differenzierung zwischen Neurapraxie, Axonotmesis und Neurotmesis oftmals eine große Herausforderung dar. Vor allem im Frühstadium von Nervenläsionen ist eine korrekte Klassifizierung des Schädigungstyps jedoch von essenzieller Bedeutung, da hiermit das therapeutische Konzept, insbesondere das operative Vorgehen und damit die Prognose, maßgebend bestimmt werden. Neben einer ausführlichen klinischen Statuierung und Anamneseerhebung bedarf es zur Präzisierung der Diagnose den Einsatz ergänzender elektrophysiologischer (funktioneller) und/oder bildgebender Untersuchungen. Eine elektrophysiologische Diagnostik kann hierbei Auskunft über Lokalisation, Schweregrad, Verlauf, Schädigungstyp und einer beginnenden oder stattgehabten Reinnervation geben. Präoperativ sollten hinsichtlich der funktionellen Diagnostik eine Neurografie, Nadel-Elektromyografie (EMG) und ggf. evozierte Potentiale (EP) und bildgebend eine Nervensonografie oder Magnetresonanztomografie (MRT) durchgeführt werden. Ergänzend kann eine EMG auch intraoperativ erfolgen.

In the early stage of nerve lesions, the clinical differentiation between neurapraxia, axonotmesis and neurotmesis often presents a big challenge. Especially in the early stage, however, it is crucial to correctly classify the type of damage because this is what essentially determines the therapeutic concept, in particular the surgical approach and, therefore, the prognosis. A precise diagnosis not only requires detailed clinical assessment and medical history taking, but also the use of additional electrophysiological (functional) and/or imaging examinations. Electrophysiological diagnostic tests may provide information ion localization, severity, course, type of damage and incipient or past reinnervation. Preoperative functional diagnostic measures should include neurography, needle electromyography (EMG) and, if needed, evoked potentials (EP), while imaging procedures should include neural sonography and magnetic resonance imaging (MRI). As a complimentary procedure, EMG may also be performed during surgery.Im Frühstadium von Nervenläsionen stellt die klinische Differenzierung zwischen Neurapraxie, Axonotmesis und Neurotmesis oftmals eine große Herausforderung dar. Vor allem im Frühstadium von Nervenläsionen ist eine korrekte Klassifizierung des Schädigungstyps jedoch von essenzieller Bedeutung, da hiermit das therapeutische Konzept, insbesondere das operative Vorgehen und damit die Prognose, maßgebend bestimmt werden. Neben einer ausführlichen klinischen Statuierung und Anamneseerhebung bedarf es zur Präzisierung der Diagnose den Einsatz ergänzender elektrophysiologischer (funktioneller) und/oder bildgebender Untersuchungen. Eine elektrophysiologische Diagnostik kann hierbei Auskunft über Lokalisation, Schweregrad, Verlauf, Schädigungstyp und einer beginnenden oder stattgehabten Reinnervation geben. Präoperativ sollten hinsichtlich der funktionellen Diagnostik eine Neurografie, Nadel-Elektromyografie (EMG) und ggf. evozierte Potentiale (EP) und bildgebend eine Nervensonografie oder Magnetresonanztomografie (MRT) durchgeführt werden. Ergänzend kann eine EMG auch intraoperativ erfolgen.

Introduction In patients with ulnar neuropathy at the elbow (UNE) the precise determination of the site of lesion is important for subsequent differential diagnostic considerations and therapeutic management. Due to a paucity of comparable data, to better define the role of different diagnostic tests, we performed the first prospective study comparing the diagnostic accuracy of short segment nerve stimulation, nerve ultrasonography, MR neurography (MRN), and diffusion tensor imaging (DTI) in patients with UNE. Methods UNE was clinically diagnosed in 17 patients with 18 affected elbows. For all 18 affected elbows in patients and 20 elbows in 10 healthy volunteers, measurements of all different diagnostic tests were performed at six anatomical positions across the elbow with measuring points from distal (D4) to proximal (P6) in relation to the medial epicondyle (P0). Additional qualitative assessment regarding structural changes of surrounding nerve anatomy was conducted. Results The difference between affected arms of patients and healthy control arms were most frequently the largest at measure intervals D2 to P0 and P0 to P2 for electrophysiological testing, or measure points P0 and P2 for all other devices, respectively. At both levels P0 and at P2, T2 contrast-to-noise ratio (CNR) of MRN and mean diffusivity (MD) of DTI-based MRN showed best accuracies. Discussion This study revealed differences in diagnostic performance of tests concerning a specific location of UNE, with better results for T2 contrast to noise ratio (CNR) in MRN and mean diffusivity of DTI-based MRN. Additional testing with MRN and nerve ultrasonography is recommended to uncover anatomical changes.

We present a comprehensive opto-electronic simulation framework for the computational analysis and optimization of perovskite-silicon tandem solar cells, consisting of a combination of a multiscale optical model for the simultaneous consideration of interference in thin coatings and scattering at textured interfaces with a mixed electronic-ionic drift-diffusion transport model that captures the peculiarities of the geometries and materials used in the tandem architecture.

We present a comprehensive approach to the characterization and modeling of photovoltaic metal-halide perovskite single junction devices and perovskite-silicon tandem solar cells. The framework is based on 1D opto-electronic device simulation in steady-state and transient modes as well as frequency domain including specific features of the perovskite materials such as mobile ions, combined with a broad variety of device characterization experiments. As a salient feature, advanced optimization algorithms are used for reliable parameter extraction and opto-electronic device optimization purposes in both single junction and tandem solar cell architectures.

In light‐emitting electrochemical cells (LECs), the position of the emission zone (EZ) is not predefined via a multilayer architecture design, but governed by a complex motion of electrical and ionic charges. As a result of the evolution of doped charge transport layers that enclose a dynamic intrinsic region until steady state is reached, the EZ is often dynamic during turn‐on. For thick sandwich polymer LECs, a continuous change of the emission color provides a direct visual indication of a moving EZ. Results from an optical and electrical analysis indicate that the intrinsic zone is narrow at early times, but starts to widen during operation, notably well before the electrical device optimum is reached. Results from numerical simulations demonstrate that the only precondition for this event to occur is that the mobilities of anions (µa) and cations (µc) are not equal, and the direction of the EZ shift dictates µc > µa. Quantitative ion profiles reveal that the displacement of ions stops when the intrinsic zone stabilizes, confirming the relation between ion movement and EZ shift. Finally, simulations indicate that the experimental current peak for constant‐voltage operation is intrinsic and the subsequent decay does not result from degradation, as commonly stated.

The primary goal of the surgical treatment of upper brachial plexus injuries is to restore active elbow flexion. Accordingly, Oberlin's transfer has been frequently performed since 1994 and has influenced the development of other nerve transfers. However, the window of opportunity for nerve transfers remains a subject of controversy. The objective of this study was to assess magnetic resonance (MR) neurographic, clinical and electrophysiological long-term results after Oberlin's transfer. For this purpose, we performed a retrospective follow-up study. Six patients with upper brachial plexus or musculocutaneous nerve injuries were assessed; 2 were iatrogenic nerve injuries following shoulder arthroscopy or neurofibroma resection. Direct and indirect signs of neuropathy were objectified with MR neurography. Moreover, clinical and electrodiagnostic follow-up was performed and all patients completed the Disabilities of Arm, Shoulder and Hand score. Mean follow-up was 48 ± 21.9 (range, 20-73) months. Mean age was 40 ± 11.3 years and mean delay to surgery was 9 ± 3.2 months. All patients were satisfied with the functional results and the median Disabilities of Arm, Shoulder and Hand score was 21 (range, 1-57). Biceps strength was improved in 5 patients from Medical Research Council grade M0 to M4-5 and in one patient to M2-3. The donor nerve showed normal motor and sensory action potentials. Follow-up MR neurography demonstrated biceps reinnervation. Taken together, this study reports good long-term results after Oberlin's transfer. MR neurography represents an excellent, noninvasive preoperative planning tool and can be of high value in selected postoperative cases. The combined evaluation of nerves and muscles may help to indicate nerve transfers in delayed cases.

In Numerical Weather Prediction (NWP), forecast systems are used to transform meteorological observations into forecasts that provide the basis for information services to the general public and many other users. In oceanography, in order to best exploit the observations, it is similarly necessary to transform them into coherent analyses and predictions that can be the basis for information services about the marine environment, its ecosystem, and the cryosphere that can be used in many applications and that can provide boundary data for weather predictions. Marine industries (e.g., commercial fishing, aquaculture, shipping, oil and gas, renewable energy, tourism), government agencies (e.g., those responsible for search and rescue, defense, coastal management, environmental protection), and other stakeholders (e.g., recreation, water sports, artisanal and sport fishing) depend on timely and accurate information about the marine environment. This includes ocean physical and biological states, the weather, and for some areas, ice cover from hours to weeks in advance as well as in the past. Supported by progress in numerical ocean modeling and data assimilation methods; increased supercomputing capacity; and most importantly, enhanced, routine, and sustained in situ and remotely sensed ocean observations, the last decade saw the development and operational implementation of mesoscale (eddy-resolving) short- and medium-range (days to weeks) ocean forecasting and reanalysis capabilities at many operational weather and ocean forecasting centers. The building and maintaining of operational ocean forecasting systems require a wide range of expertise. Most global ocean forecasting systems transition from research and demonstration modes to sustained, permanent operational capabilities with attendant infrastructure (European Commission 2015). Beyond the traditional short-term forecasting of physical ocean properties (temperature, salinity, surface height, currents, waves), marine activities such as water quality and habitat management as well as climate research increasingly rely on operational oceanographic data and products. To satisfy existing and new requirements for end-use applications, such as coastal protection, ecosystem monitoring and forecasting, and climate monitoring, these operational ocean forecasting systems must be sustained, as well as evolve and improve, to remain relevant with broad utility.

​This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials & Interfaces, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsami.9b04991, A variety of experiments on vacuum-deposited methylammonium lead iodide perovskite solar cells are presented, including JV curves with different scan rates, light intensity-dependent open-circuit voltage, impedance spectra, intensity-modulated photocurrent spectra, transient photocurrents, and transient voltage step responses. All these experimental data sets are successfully reproduced by a charge drift-diffusion simulation model incorporating mobile ions and charge traps using a single set of parameters. While previous modeling studies focused on a single experimental technique, we combine steady-state, transient, and frequency-domain simulations and measurements. Our study is an important step toward quantitative simulation of perovskite solar cells, leading to a deeper understanding of the physical effects in these materials. The analysis of the transient current upon voltage turn-on in the dark reveals that the charge injection properties of the interfaces are triggered by the accumulation of mobile ionic defects. We show that the current rise of voltage step experiments allow for conclusions about the recombination at the interface. Whether one or two mobile ionic species are used in the model has only a minor influence on the observed effects. A delayed current rise observed upon reversing the bias from +3 to -3 V in the dark cannot be reproduced yet by our drift-diffusion model. We speculate that a reversible chemical reaction of mobile ions with the contact material may be the cause of this effect, thus requiring a future model extension. A parameter variation is performed in order to understand the performance-limiting factors of the device under investigation.

We introduce a new tool – the Spectral Taylor Diagram (STD) – for the comparison of time series in the frequency domain. The STD provides a novel way of displaying the squared-coherence, power, amplitude, phase, and root-mean-squared difference of discrete frequencies of two time-series. Each STD summarises these quantities in a single plot, for multiple targeted frequencies. The versatility of STDs is demonstrated through a series of sea-level comparisons between observations from tide gauges, and model results from a global eddy-permitting ocean general circulation model with explicit tidal forcing.

In 1998 the Australian Government released ‘Australia’s Ocean Policy: Caring, Understanding, Using Wisely’ (Environment Australia 1998a). The policy, released in the International Year of Oceans, r...

Analyses of the variability in a 3.5-year run of a hydrodynamic model developed for simulating the circulation of the Great Barrier Reef (GBR) are presented. Sea-surface temperature, salinity, currents and cross-shelf transports between the GBR lagoon and the deep ocean offshore are investigated and compare well to available observations. Water mass intrusions and flushing events are critical factors in determining the health of coral reef and continental shelf ecosystems. Results from tracer release experiments provide a synoptic view of the variability of residence times within the GBR and identify critical regions of shelf-ocean exchange. One such region of significant tracer contribution to the shelf is identified in the vicinity of the Pompey Reefs in an area characterised by increased frequency of upslope transported water. Another location of enhanced flux on to the shelf exists in the region bracketing Palm Passage, where the reef matrix is very open, and provides little obstacle to cross-shelf exchange. The Palm Passage location is the origin of a northwards plume of elevated concentration. The model circulation provides a robust and useful picture of the Great Barrier Reef, rendering the model suitable for providing input to biogeochemical and sediment models to simulate, at a broad scale, the ecosystem health, water quality, transport and fate of water and waterborne material, moving through catchments and into the GBR lagoon.

The drastic reduction in the number of observation data from the Tropical Atmospheric Ocean (TAO)/Triangle Trans-Ocean Buoy Network (TRITON) array since 2012 has given rise to a need to assess the impact of those data in ocean data assimilation (DA) systems. This article provides a review of existing studies evaluating the impacts of data from the TAO/TRITON array and other components of the Tropical Pacific Observing System (TPOS) on current ocean DA systems used for a variety of operational and research applications. It can be considered as background information that can guide the evaluation exercise of TPOS. Temperature data from TAO/TRITON array are assimilated in most ocean DA systems which cover the tropical Pacific in order to constrain the ocean heat content, stratification, and circulation. It is shown that the impacts of observation data depend considerably on the system and application. The presence of model error often makes the results difficult to interpret. Nevertheless there is consensus that the data from TAO/TRITON generally have positive impacts complementary to Argo floats. In the equatorial Pacific, the impacts are generally around the same level or larger than those of Argo. We therefore conclude that, with the current configuration of TPOS, the loss of the TAO/TRITON data is having a significant detrimental impact on many applications based on ocean DA systems. This conclusion needs to be kept under review because the equatorial coverage by Argo is expected to improve in the future.

We present a new methodology that allows quantifying the impact of individual terms of the temperature and salinity conservation within the mixed layer on mixed layer depth (MLD). The method is applied to output from an ocean general circulation model in the Indian Ocean to investigate variability and changes in MLD. On seasonal timescales and for most areas of the Indian Ocean variability of MLD is tightly linked to all thermohaline budget terms. In the Indian Ocean at approximately 20°S the MLD covaries with surface heat and freshwater fluxes on intraseasonal and interannual timescales. The geography of the region includes the Leeuwin Current, plus the tropical eastern Indian Ocean for interannual surface freshwater fluxes. The range of seasonal amplitudes of MLD variability varies with individual budget terms but is typically within 1 m/month to 100 m/month. The ocean footprints of an intraseasonal tropical cyclone, tropical and midlatitude seasonal temperature and salinity budgets and interannual variability associated with the Indian Ocean Dipole Mode are analyzed. The results reveal close relationships of the thermohaline budgets within the mixed layer with the variability of the MLD. The associated tendencies of changes in MLD are consistent with Argo and satellite-based observations of tendencies within the mixed layer and sea-surface temperature and salinity.

Marine heat waves along the Western Australian coast are potentially damaging to the marine environment especially coastal fisheries and the Ningaloo Reef. Initiation and amplification mechanisms for marine heat waves (referred to as ‘Ningaloo Nino’ events) are explored using ocean and atmosphere reanalyses for the period 1960–2011. We find that the onset stage from October to November is promoted by wind-evaporation-SST feedback that operates to the northwest of the coast on the north-eastern flank of the Mascarene subtropical high: cyclonic anomalies act to reduce the surface wind speed and warm the ocean surface, thereby driving increased rainfall and stronger cyclonic anomalies. The growth and southward expansion of positive SST anomalies along the Australian west coast is further supplemented by anomalous poleward advection of heat by the Leeuwin Current, which is coupled with the cyclonic anomalies off the coast. The strongest Ningaloo Nino events, such as the record strong 2011 event, occur in conjunction with La Nina conditions in the Pacific, which drives westerly wind anomalies to the northwest of Australia that can promote the WES feedback and accelerate the Leeuwin Current via transmission of thermocline anomalies from the western Pacific onto the west Australian coast. However, many Ningaloo Nino events occur independent of La Nina and some Ningaloo Nino events even occur during certain El Ninos. We explain this general independence from ENSO because the triggering of Ningaloo Nino events from the Pacific is most sensitive to antecedent SST anomalies in the far western Pacific, rather than in the central Pacific where ENSO typically has greatest magnitude.

Ningaloo Nino refers to the episodic occurrence of anomalously warm ocean conditions along the subtropical coast of Western Australia (WA). Ningaloo Nino typically develops in austral spring, peaks in summer, and decays in autumn, and it often occurs in conjunction with La Nina conditions in the Pacific which promote poleward transport of warm tropical waters by the Leeuwin Current. Since the late 1990s, there has been a marked increase in the occurrence of Ningaloo Nino, which is likely related to the recent swing to the negative phase of the Interdecadal Pacific Oscillation (IPO) and enhanced El Nino–Southern Oscillation variance since 1970s. The swing to the negative IPO sustains positive heat content anomalies and initiates more frequent cyclonic wind anomalies off the WA coast so favoring enhanced poleward heat transport by the Leeuwin Current. The anthropogenically forced global warming has made it easier for natural variability to drive extreme ocean temperatures in the region.

Eddy-resolving global ocean models are highly desired for spatially-improved climate studies, but this is challenging because they require careful configuration and substantial computational resources. Model drift, partially related to insufficient model spin-up, imperfect model physics or bias in surface forcing, can be problematic, leading to contamination of climate change signals. In this study, we adapt a near-global eddy-resolving ocean general circulation model, originally developed for short-range ocean forecasting, for climate studies. The Ocean Forecasting Australia Model version 3 (OFAM3) is spun up for 20 years, with repeated year 1979 forcing and adaptive relaxation (Newtonian nudging) of temperature and salinity in the deep ocean to an observation-based climatology. In addition, surface heat fluxes from the JRA-55 atmospheric reanalysis are adjusted during the spin-up experiment to minimise excessive net heat uptake in the ocean. In the historical experiment, spanning 1979–2014, a non-adaptive relaxation is applied by repeating the same relaxation rates derived from the last five years of the spin-up experiment, and the surface heat flux adjustment diagnosed during the spinup experiment is also maintained. We demonstrate that the historical experiment driven by the JRA-55 reanalysis does not have significant drifts (e.g., as shown by simulated global ocean heat content), and also provides an eddy-resolving simulation of the global ocean circulation over the period 1979–2014. Decadal changes, such as the strengthening of the subtropical gyre circulation, are also reasonably simulated. A biogeochemical model is coupled with OFAM3 to produce patterns of primary productivity and carbon fluxes that are consistent with observations. Experiences gained from our numerical experiments will be helpful to other modelling groups who are interested in running global eddy-resolving OGCMs for climate studies.

Effects of ion concentration and active layer thickness play a critical role on the performance of light-emitting electrochemical cells. Expanding on a pioneering materials system comprising the super yellow (SY) polymer and the electrolyte trimethylolpropane ethoxylate (TMPE)/Li+CF3SO3-, it is reported that a slightly lowered salt concentration and layer thickness result in a substantial efficiency increase, and that this increase is confined to a narrow concentration and thickness range. For a film thickness of 70 nm, a blend ratio SY:TMPE:Li+CF3SO3- = 1:0.075:0.0225, and a current of 7.7 mA cm(-2) the current efficacy is 11.6 cd A(-1), on a par with SY light-emitting diodes. The optimized salt content can be explained by increased exciton quenching at higher concentrations and hindered carrier injection and conduction at lower concentrations, while the optical dependence on the layer thickness is due to weak microcavity effects. A comprehensive optical modeling study is presented, which includes the doping-induced changes of the refractive indices and self-absorption losses due the emission-absorption overlap of intrinsic and doped SY. The analysis indicates either a thickness-independent emitter position (EP) close to the anode or a thickness-dependent EP, shifted to the cathode for increased thicknesses.

Background Assessing nerve traumas in children is challenging. Electrodiagnostic studies are often not tolerated. We tested if ultrasound examination in children with recent supracondylar humerus fracture and ulnar nerve pathology was well tolerated and whether it was helpful in assessing the nerve trauma. Methods This is a retrospective analysis of all pediatric cases with recent supracondylar humerus fracture and persistent ulnar deficits presenting to our neurology outpatients clinic from October 2016 to September 2017. All patients underwent clinical neurological examination. Additional examinations in the form of EMG and nerve ultrasound using a 18 MHz hockey stick probe were proposed as additional investigations. Results Patients were aged 3–10 years (mean age 6.3 years), 4 male and 2 female. All experienced severe extension type supracondylar humerus fractures (Type III and Type IV), treated with closed (3 patients) or open reduction (3 patients) and fixed with crossed pinning (2–4 pins). Ulnar nerve deficits in intrinsic hand muscles ranged from M0 to M3. 3 patients showed complete loss of ulnar sensory motor function. 3 were able to tolerate EMG. All 6 patients tolerated and were able to complete ultrasound examination. In 1 patient with complete loss of function, discontinuity of the nerve with formation of stump neuromas was detected in ultrasound. In the other 5 cases, nerve continuity could be demonstrated, but significant nerve swelling (sulcus to upper arm ratios 1.4–2.7; mean 1.97) was apparent in all. In the 2 most severe cases of nerve swelling, additional nerve compromise with scar tissue was detected. Ultrasound findings led to surgical intervention in 2 cases (in one additional EMG data was available): 1) nerve repair by a sural nerve graft for the case of neuronotmesis and 2) neurolysis followed by anterior displacement in one case with severe nerve swelling and compromising scar tissue. Conclusions Nerve ultrasound is well tolerated in children and proved to be useful and informative for management and counselling. Useful ultrasound indicators of neuronal damage included loss of nerve continuity, neuroma formation, compromising scar tissue and nerve swelling.

Real-time operational predictions of the major ocean basins which resolve the ocean mesoscale at mid-latitudes have become established in more than a dozen countries over the last 15 years. These predictions depend on the global ocean observing system (particularly satellite altimeters and the Argo profiling float system), high performance computers and sophisticated ocean models and data assimilation systems. They support an expanding range of information services for operations at sea, weather forecasts and protection of the environment. GODAE Oceanview (GOV) assists the groups developing these predictions. This paper provides an introduction to GOV and the papers in this special issue.