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•Electrospun nanofiber inserts are promising novel ocular drug delivery systems.•The biocompatible polymer nanofibers instantly dissolve in tear fluid.•Molecularly dispersed drugs are ...immediately released and available.•Solid fiber formulations do not require preservatives or pH/tonicity adjustment.•No fluid volume is added to the eye and retention time is increased.
Liquid and semi-solid formulations are the most commonly used drug delivery systems for ophthalmic diseases. Upon application into the conjunctival sac, these systems introduce a variable and unphysiologically high liquid volume to the eye, resulting in overflow and extensive nasolacrimal drainage, accounting for dosing inaccuracy and short ocular residence time. In this study, we present nanofibrous electrospun scaffolds composed of biocompatible polymers, overcoming these challenges by immediate drug release. The fibers incorporate gentamicin and dexamethasone, intended for the treatment of bacterial conjunctivitis. Upon contact with the ocular surface, the nanofibers immediately dissolve in the tear fluid, quantitatively releasing the two actives, yielding over92% drug recovery, determined with fluorimetric and chromatographic quantifications methods. Simultaneously, the viscosity of the tear fluid increases, shown by complex viscometry measurements. A newly developed ex vivo microfluidic porcine cornea model was used to evaluated ocular residence time. In contrast to fluid eye drops, the contact time was significantly prolonged and 20 min after application, an increase in drug availability on the ocular surface of 342% was observed. Biocompatibility of the polymer system was demonstrated in an OECD approved in vitro cornea model. The antibacterial activity after processing was evaluated according to EUCAST guidelines, and storage stability of the system was confirmed over a 12-week period.
This innovative drug delivery system poses a highly promising platform technology, overcoming challenges associated with conventional dosage forms for drug delivery to the anterior eye and thus significantly advancing therapeutic approaches.
Fostered by and embedded in the general development of information and communications technology (ICT), the evolution of tsunami warning systems (TWS) shows a significant development from ...seismic-centred to multi-sensor system architectures using additional sensors (e.g. tide gauges and buoys) for the detection of tsunami waves in the ocean. Currently, the beginning implementation of regional tsunami warning infrastructures indicates a new phase in the development of TWS. A new generation of TWS should not only be able to realise multi-sensor monitoring for tsunami detection. Moreover, these systems have to be capable to form a collaborative communication infrastructure of distributed tsunami warning systems in order to implement regional, ocean-wide monitoring and warning strategies. In the context of the development of the German Indonesian Tsunami Early Warning System (GITEWS) and in the EU-funded FP6 project Distant Early Warning System (DEWS), a service platform for both sensor integration and warning dissemination has been newly developed and demonstrated. In particular, standards of the Open Geospatial Consortium (OGC) and the Organization for the Advancement of Structured Information Standards (OASIS) have been successfully incorporated. In the FP7 project Collaborative, Complex and Critical Decision-Support in Evolving Crises (TRIDEC), new developments in ICT (e.g. complex event processing (CEP) and event-driven architecture (EDA)) are used to extend the existing platform to realise a component-based technology framework for building distributed tsunami warning systems.
The German Indonesian Tsunami Early Warning System (GITEWS) is built upon a complex sensor data infrastructure. To best fulfill the demand for a long living system, the underlying software and ...hardware architecture of GITEWS must be prepared for future modifications both of single sensors and entire sensors systems. The foundation for a flexible integration and for stable interfaces is a result of following the paradigm of a Service Oriented Architecture (SOA). The Tsunami Service Bus (TSB) - our integration platform in GITEWS - realizes this SOA approach by implementing the Sensor Web Enablement (SWE) standards and services. This paper focuses on architectural and implementation aspects of the TSB. Initially, the general architectural approach in GITEWS by SOA and SWE is presented. Based on this conception, the concrete system architecture of GITEWS is introduced. The sensor integration platform TSB is then discussed in detail, following by its primary responsibilities and components. Special emphasis is laid on architectural transparency, comprehensible design decisions, and references to the applied technology.
Machine damage due to tool collisions is a widespread issue in milling production. These collisions are typically caused by human errors. A solution for this problem is proposed based on a ...low-complexity 24 GHz continuous wave (CW) radar system. The developed monitoring system is able to detect moving objects by evaluating the Doppler shift. It combines incoherent information from several spatially distributed Doppler sensors and estimates the distance between an object and the sensors. The specially designed compact prototype contains up to five radar sensor modules and amplifiers yet fits into the limited available space. In this first approach we concentrate on the Doppler-based positioning of a single moving target. The recorded signals are preprocessed in order to remove noise and interference from the machinery hall. We conducted and processed system measurements with this prototype. The Doppler frequency estimation and the object position obtained after signal conditioning and processing with the developed algorithm were in good agreement with the reference coordinates provided by the machine's control unit.
This paper proposes a consumption-based model that accounts for many features of the nominal term structure of interest rates. The driving force behind the model is a time-varying price of risk ...generated by external habit. Nominal bonds depend on past consumption growth through habit and on expected inflation. When calibrated to data on consumption, inflation, and the aggregate market, the model produces realistic means and volatilities of bond yields and accounts for the expectations puzzle. The model also captures the high equity premium and excess stock market volatility.
Analysis was performed to determine whether a lightning flash could be associated with every reported lightning-initiated wildfire that grew to at least 4 km(exp 2). In total, 905 lightning-initiated ...wildfires within the Continental United States (CONUS) between 2012 and 2015 were analyzed. Fixed and fire radius search methods showed that 81–88% of wildfires had a corresponding lightning flash within a 14 day period prior to the report date. The two methods showed that 52–60% of lightning-initiated wildfires were reported on the same day as the closest lightning flash. The fire radius method indicated the most promising spatial results, where the median distance between the closest lightning and the wildfire start location was 0.83 km, followed by a 75th percentile of 1.6 km and a 95th percentile of 5.86 km. Ninety percent of the closest lightning flashes to wildfires were negative polarity. Maximum flash densities were less than 0.41 flashes km(exp 2) for the 24 h period at the fire start location. The majority of lightning-initiated holdover events were observed in the Western CONUS, with a peak density in north-central Idaho. A twelve day holdover event in New Mexico was also discussed, outlining the opportunities and limitations of using lightning data to characterize wildfires.
Zusammenfassung
Heterogene Datenstrukturen führen bei bundeslandübergreifenden Projekten zur 3D- und Grundwassermodellierung oft zu hohen Barrieren bei der Bearbeitung. Zur Beleuchtung und ...Überwindung solcher Barrieren wurden in einer Pilotstudie drei grenzübergreifende Projektgebiete (Hessen/Bayern, Hessen/Baden-Württemberg und Hessen/Rheinland-Pfalz) im Maßstab 1:25.000 definiert. Strukturgeologisch sind die Arbeitsgebiete im nördlichen Oberrheingraben sowie in der Hanau-Seligenstädter Senke angesiedelt. Die von den geologischen Landesämtern zur Verfügung gestellten Bohrschichtinformationen wurden nach technischen und inhaltlichen Kriterien verglichen und zusammengeführt. Anschließend wurden die Daten mit zuvor definierten Wasserdurchlässigkeitsklassen parametrisiert und im 3D-Raum interpoliert, um eine Abschätzung der Durchlässigkeitsbeiwerte zu ermöglichen. Daneben wurden für ein Teilgebiet Schichtdaten in einem einheitlichen lithostratigraphischem Konzept vereinigt und bundeslandübergreifend Trennhorizonte modelliert. Ein semiautomatisches Zusammenführen der petrographischen Informationen gelang für einen Großteil der Schichten. Die Modellierergebnisse zeigen ein flächenhaftes Auftreten grundwasserleitender Schichten bis etwa 40 m unter Geländeoberkante und ein nicht-flächendeckendes Auftreten geringleitender Schichten in den im Liegenden folgenden 30 Metern. Zudem korreliert das Durchlässigkeitsmodell gut mit dem erstellten Trennflächenmodell.
The aim of this study was to evaluate the influence of microstructural parameters, such as porosity and osteon dimensions, on strength. Therefore, the predictive value of bone mineral density (BMD) ...measured by quantitative computed tomography (QCT) for intracortical porosity and other microstructural parameters, as well as for strength of cortical bone biopsies, was investigated. Femoral cortical bone specimens from the middiaphysis of 23 patients were harvested during total hip replacement while drilling a hole (dia. 4.5 mm) for the relief of the intramedullary pressure. In vitro structural parameters assessed in histological sections as well as BMD determined by quantitative computed tomography were correlated with yield stress, and elastic modulus assessed by a compression test of the same specimens. Significant correlations were found between BMD and all mechanical parameters (elastic modulus: r = 0.69, p < 0.005; yield stress: r = 0.64, p < 0.005). Significant correlations between most structural parameters assessed by histology and yield stress were discovered. Structural parameters related to pore dimensions revealed higher correlation coefficients with yield stress (r = −0.69 for average pore diameter and r = −0.62 for fraction of porous structures, p < 0.005) than parameters related to osteons (r = 0.60 for osteon density and average osteonal area, p < 0.005), whereas elastic modulus was predicted equally well by both types of parameters. Significant correlations were found between BMD and parameters related to porous structures (r = 0.85 for porosity, 0.80 for average pore area, and r = 0.79 for average pore diameter in polynomial regression, p < 0.005). Histologically assessed porosity correlated significantly with parameters describing porous structures and haversian canal dimensions. Our results indicate a relevance of osteon density and fraction of osteonal structures for the mechanical parameters of cortical bone. We consider the measurement of BMD by quantitative computed tomography to be helpful for the estimation of bone strength as well as for the prediction of intracortical porosity and parameters related to porous structures of cortical bone.
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