Entity linking systems for literature reviews

Scientometrics - Computer-assisted methods and tools can help researchers automate the coding process of literature reviews and accelerate the literature review process. However, existing...     

Uncertainties in the determination of pyrrolizidine alkaloid levels in naturally contaminated honeys and comparison of results obtained by different analytical approaches

The contamination of honey with hepatotoxic pyrrolizidine alkaloids (PAs) is a well-known hazard for food safety. While management strategies and controls of the honey industry aim to reduce the PA levels, uncertainties remain with regard to the safety of regionally produced and marketed honey. In addition, a previous study showed large differences of results obtained after various periods of storage and apparent differences between the analytical results of different laboratories. Therefore, this study aimed at examining these uncertainties by monitoring the impact of storage on the PA and PA N-oxide (PANO) content of two freshly harvested honeys and on possible demixing effects caused by pollen settling. Additionally, three analytical approaches – target analysis with matrix-matched calibration or standard addition and a sum parameter method – were applied for a comparative analysis of 20 honeys harvested in summer 2016. All samples originated from Schleswig-Holstein in Northern Germany where the PA plant Jacobaea vulgaris is currently observed on a massive scale. The results of the time series analyses showed that PANO levels markedly decreased within a few weeks and practically reached the LOD 16 weeks after harvest. Tertiary PAs, by contrast, remained stable and did not increase as a consequence of PANO decrease. The experiments on a putative demixing, which may result in a heterogeneous distribution of PAs/PANOs, revealed that there was no such effect during storage of up to 12 weeks. A comparison of the PA/PANO levels obtained by different analytical approaches showed that in some cases the sum parameter method yielded much higher levels than the target approaches, whereas in other cases, the target analysis with standard addition found higher levels than the other two methods. In summary, the results of this study highlight uncertainties regarding the validity and comparability of analytical results and consequently regarding health risk assessment.     

Cultivation and downstream processing of microalgae and cyanobacteria to generate protein-based technofunctional food ingredients

Abstract

Microalgae are unicellular microorganisms that can be rich in proteins and are therefore a valuable ingredient in different foods. So far microalgae are mainly utilized in foods in low concentrations as a whole-cell ingredient even though it is known that proteins extracted from microalgae can possibly posess various technofunctional properties, such as high protein solubility, emulsification, foaming, and gelation properties. The widespread usage of protein-rich ingredients obtained from microalgae is for the most part prevented by the high price of the biomass, the lack of efficient downstream processes, and the adverse taste. The aim of this review is to give insights into the fundamental properties of the growth and processing of microalgae, highlight the advantages of microalgae ingredients and show potential applications based on the technofunctional, nutritional and sensory properties that were reported. Moreover, the existing challenges and knowledge gaps that hinder the application of microalgal proteins in foods are discussed.     

The Determinants of Debt and (Private) Equity Financing: The Case of Young, Innovative SMEs from Germany

Financial theory creates a puzzle. Some authors argue that high-risk entrepreneurs choose debt contracts instead of equity contracts since risky but high returns are of relatively more value for a loan-financed firm. Conversely, authors who focus explicitly on start-up finance predict that entrepreneurs are the more likely to seek equity-like venture capital contracts, the more risky their projects are. Our paper is an initial step towards resolving this puzzle empirically. We present microeconometric evidence on the determinants of debt and equity financing in young and innovative SMEs. We pay special attention to the role of risk for the choice of the method of financing. Since risk is not directly observable we use different indicators for financial and project risk. It turns out that our data generally confirms the hypothesis that the probability that a young high-tech firm receives equity financing is an increasing function of the financial risk. With regard to the intrinsic project risk, our results are less conclusive, as some of our indicators of a risky project are found to have a negative effect on the likelihood to be financed by private equity.     

Diurnal and spatial variation of xylem dielectric constant in Norway Spruce (Picea abies [L.] Karst.) as related to microclimate, xylem sap flow, and xylem chemistry

Spatial and temporal variations in vegetation dielectric properties strongly influence the microwave backscatter characteristics of forested landscapes. This paper examines the relationship between xylem tissue dielectric constant, xylem sap flux density, and xylem sap chemical composition as measured in the stems of two Norway Spruce (Picea abies [L.] Karst.) trees in the Fichtelgebirge region of Northern Bavaria, Germany. Dielectric constant and xylem sap flux were monitored continuously from June through October 1995, at several heights along the tree trunks. At the end of the measurement series, each tree was harvested, and its xylem sap extracted and analyzed to determine the concentrations of amino acids and cations. Results show that the sap flux density was correlated with vapor pressure deficit (VPD) at all heights in the stem. In contrast, the xylem tissue dielectric constant is influenced by VPD but can exhibit a significant temporal lag relative to changes in VPD. This lag varies with position along the tree trunk. The temporal variability of the dielectric constant is compared with both trees at several positions along the tree trunks. Results of xylem sap chemical analysis are presented. We show that spatial and temporal variability in the xylem tissue dielectric constant is influenced not only by water content, but by variations in xylem sap chemistry as well. This has important implications for microwave remote sensing of forested landscapes, as useful information may be acquired regarding stand physiology and water relations and where variations in dielectric properties within individual trees and across geographic areas can be significant error sources for forest inventory mapping.     

A vectorial vibrating reed magnetometer with high sensitivity

A vibrating reed magnetometer with high sensitivity is constructed. Using optical signal pickup, modified excitation coils, and an acoustical reference excitation system, the high sensitivity of former constructions is combined with the detection of the magnetization component perpendicular to the bias field H. The calibration procedure providing increased reliability is simplified and allows hysteresis measurements with the magnetic easy axis of the sample oriented at an arbitrary angle with respect to H. Measurement results are given in order to demonstrate the performance of the apparatus     

Enabling simulation interoperability

Over the past years a series of architectures have addressed the need to link multiple simulations. These efforts have been driven primarily by the desire to reuse existing "best of breed" simulations in new combinations to avoid developing any single, monolithic architecture with the impossible goal of meeting all simulation needs. The US Department of Defense began developing the high level architecture (HLA) for distributed computer simulation systems. The high level architecture addresses the need to link multiple computer simulation systems. HLA separates the data model from the architecture's functions for exchanging information.