A linear model to derive melt pond depth on Arctic sea ice from hyperspectral data

Melt ponds are key elements in the energy balance of Arctic sea ice. Observing their temporal evolution is crucial for understanding melt processes and predicting sea ice evolution. Remote sensing is the only technique that enables large-scale observations of Arctic sea ice. However, monitoring melt pond deepening in this way is challenging because most of the optical signal reflected by a pond is defined by the scattering characteristics of the underlying ice. Without knowing the influence of meltwater on the reflected signal, the water depth cannot be determined. To solve the problem, we simulated the way meltwater changes the reflected spectra of bare ice. We developed a model based on the slope of the log-scaled remote sensing reflectance at 710 nm as a function of depth that is widely independent from the bottom albedo and accounts for the influence of varying solar zenith angles. We validated the model using 49 in situ melt pond spectra and corresponding depths from shallow ponds on dark and bright ice. Retrieved pond depths are accurate (root mean square error, RMSE=2.81 cm; nRMSE=16 %) and highly correlated with in situ measurements (r=0.89; p=4.34×10−17

Image-based window detection: an overview

Automated segmentation of buildings’ façade and detection of its elements is of high relevance in various fields of research as it, e. g., reduces the effort of 3 D reconstructing existing buildings and even entire cities or may be used for navigation and localization tasks. In recent years, several approaches were made concerning this issue. These can be mainly classified by their input data which are either images or 3 D point clouds. This paper provides a survey of image-based approaches. Particularly, this paper focuses on window detection and therefore groups related papers into the three major detection strategies. We juxtapose grammar based methods, pattern recognition and machine learning and contrast them referring to their generality of application. As we found out machine learning approaches seem most promising for window detection on generic façades and thus we will pursue these in future work

Large-scale purification of factor VIII by affinity chromatography: optimization of process parameters

The optimization of a new process for the extraction of human coagulation factor VIII (FVIII) from plasma with the tailor-made affinity matrix dimethylaminopropylcarbamylpentyl-Sepharose CL-4B (C3---C5 matrix) is described. First, plasma is applied to DEAE-Sephadex A-50 anion exchanger in order to separate a number of proteins, including coagulation factors II, IX and X (prothrombin complex), from FVIII. Subsequently, the unbound fraction of the ion exchanger, containing FVIII, is contacted with the C3---C5 affinity matrix. Optimization of the FVIII affinity chromatographic procedure is accomplished in terms of the ligand density of the matrix, adsorption mode (batch-wise versus column-wise adsorption and matrix to plasma ratio), and conditions of pH and conductivity to be applied on washing and desorption. In scale-up experiments, by processing 20 1 of plasma, the recovery (340 U VIII:C/kg plasma) and the specific activity (s.a.) (1.2 U VIII:C/mg protein) are better than those obtained by cryoprecipitation (recovery 300 U VIII:C/kg plasma, s.a. O.3 U VIII:C/mg protein). The newly developed process using the specially designed C3---C5 affinity matrix has potential application in the process-scale purification of FVIII

Application of Sentinel-2 MSI in Arctic Research: Evaluating the Performance of Atmospheric Correction Approaches Over Arctic Sea Ice

Multispectral remote sensing may be a powerful tool for areal retrieval of biogeophysical parameters in the Arctic sea ice. The MultiSpectral Instrument on board the Sentinel-2 (S-2) satellites of the European Space Agency offers new possibilities for Arctic research; S-2A and S-2B provide 13 spectral bands between 443 and 2,202 nm and spatial resolutions between 10 and 60 m, which may enable the monitoring of large areas of Arctic sea ice. For an accurate retrieval of parameters such as surface albedo, the elimination of atmospheric influences in the data is essential. We therefore provide an evaluation of five currently available atmospheric correction processors for S-2 (ACOLITE, ATCOR, iCOR, Polymer, and Sen2Cor). We evaluate the results of the different processors using in situ spectral measurements of ice and snow and open water gathered north of Svalbard during RV Polarstern cruise PS106.1 in summer 2017. We used spectral shapes to assess performance for ice and snow surfaces. For open water, we additionally evaluated intensities. ACOLITE, ATCOR, and iCOR performed well over sea ice and Polymer generated the best results over open water. ATCOR, iCOR and Sen2Cor failed in the image-based retrieval of atmospheric parameters (aerosol optical thickness, water vapor). ACOLITE estimated AOT within the uncertainty range of AERONET measurements. Parameterization based on external data, therefore, was necessary to obtain reliable results. To illustrate consequences of processor selection on secondary products we computed average surface reflectance of six bands and normalized difference melt index (NDMI) on an image subset. Medians of average reflectance and NDMI range from 0.80–0.97 to 0.12–0.18 while medians for TOA are 0.75 and 0.06, respectively

Case Report: Clinical Use of a Patient-Individual Magnetic Resonance Imaging-Based Stereotactic Navigation Device for Brain Biopsies in Three Dogs

Three-dimensional (3D) printing techniques for patient-individual medicine has found its way into veterinary neurosurgery. Because of the high accuracy of 3D printed specific neurosurgical navigation devices, it seems to be a safe and reliable option to use patient- individual constructions for sampling brain tissue. Due to the complexity and vulnerability of the brain a particularly precise and safe procedure is required. In a recent cadaver study a better accuracy for the 3D printed MRI-based patient individual stereotactic brain biopsy device for dogs is determined compared to the accuracies of other biopsy systems which are currently used in veterinary medicine. This case report describes the clinical use of this 3D printed MRI-based patient individual brain biopsy device for brain sampling in three dogs. The system was characterized by a simple handling. Furthermore, it was an effective and reliable tool to gain diagnostic brain biopsy samples in dogs with no significant side effects

GMOs Across the Atlantic

GMOs Across the AtlanticSacrificing Precaution in the Name of Free Trade?Kofi Annan once said “[…] that arguing against globalisation is like arguing against the laws of gravity”. The world has evolved into a place of omnipresent interconnectivity where people are linked across borders by economic, political, friendly and family ties. Although risks have likewise become globalised in the process, risk management still largely constitutes a national issue. While transnational food scandals as the BSE crisis in 1997 or the horse meat scandal of 2013 have shaken consumers within and beyond the European Union (EU), Member States (MS) nonetheless continue to insist on their sovereignty to approach and handle uncertain risks by themselves. There are a variety of levels related to dealing with uncertain risks that are affected by this controversy. Amongst them are science as in risk assessment, law as in risk regulation and politics as in risk management and the overall coordinating risk governance processes. As neither science or law nor politics are able to provide fully sound and satisfying solutions for coping with uncertain risks, controversy and heated debate remains even long after a political decision has been made on a case. It is striking how all these disciplines attempt to appropriately respond to uncertainty, while they do actually add more complexity and differing opinions. There consequently is no solid ground for policy-makers to base their final decisions on and justify the particular regulation or acceptance of risks. It remains an issue how politics can effectively work in light of uncertainty. This is especially important when considering the effects of globalisation. Through international trade and the flow of goods through the world economy, products associated with uncertain risk cross national borders on a daily basis and need to be regulated. The ongoing negotiations on a free trade agreement between the European Union and the United States of America have highlighted the difficulties regarding this process. If successfully concluded, supposedly by the end of 2014, the Transatlantic Trade and Investment Partnership (TTIP) would constitute the largest free trade zone worldwide and both the EU and the US would benefit tremendously. However, negotiations have not gone so smoothly due to prevailing disagreement over the rules that should apply for the TTIP. With regards to food safety, the EU and the US have already had difficulties in the past to agree on a common denominator. Related differences and incompatibilities become evident in the debate on food safety. Although consumer protection is a highlyranked principle for both parties, there is little agreement on what requires strict protective measures and what should be regulated only mildly. In the past and recently, problematic issues for the EU have included US exports of genetically modified crops into the EU as well as meat imports from American hormone-treated or -fed animals and chicken meat that was treated with chlorine. On the part of the US, concerns have mostly been about EU lactic-acid washed meat, raw milk cheese and dairy imports into the States. Both parties have according precautionary measures in place, but request each other to drop the various bans and ease regulatory practices and processes on other products

Uncertainty in the measurement of indoor temperature and humidity in naturally ventilated dairy buildings as influenced by measurement technique and data variability

The microclimatic conditions in dairy buildings affect animal welfare and gaseous emissions. Measurements are highly variable due to the inhomogeneous distribution of heat and humidity sources (related to farm management) and the turbulent inflow (associated with meteorologic boundary conditions). The selection of the measurement strategy (number and position of the sensors) and the analysis methodology adds to the uncertainty of the applied measurement technique. To assess the suitability of different sensor positions, in situations where monitoring in the direct vicinity of the animals is not possible, we collected long-term data in two naturally ventilated dairy barns in Germany between March 2015 and April 2016 (horizontal and vertical profiles with 10 to 5 min temporal resolution). Uncertainties related to the measurement setup were assessed by comparing the device outputs under lab conditions after the on-farm experiments. We found out that the uncertainty in measurements of relative humidity is of particular importance when assessing heat stress risk and resulting economic losses in terms of temperature-humidity index. Measurements at a height of approximately 3 m–3.5 m turned out to be a good approximation for the microclimatic conditions in the animal occupied zone (including the air volume close to the emission active zone). However, further investigation along this cross-section is required to reduce uncertainties related to the inhomogeneous distribution of humidity. In addition, a regular sound cleaning (and if possible recalibration after few months) of the measurement devices is crucial to reduce the instrumentation uncertainty in long-term monitoring of relative humidity in dairy barns. © 2017 The Author

Evaluation des Arbeitnehmerüberlassungsgesetzes (AÜG): Endbericht zum Forschungsvorhaben

Der Forschungsbericht dokumentiert die Ergebnisse der Evaluation des zum April 2017 weiterentwickelten Arbeitnehmerüberlassungsgesetzes (AÜG). Die Evaluation des Gesetzes hatte zum Ziel Umsetzung und Wirksamkeit der damaligen Neuregelungen auf Grundlage wissenschaftlicher Daten und Methoden zu untersuchen. Dabei lag der Schwerpunkt der Untersuchung auf dem mit der Gesetzesreform verfolgten Ziel, die Leiharbeit auf ihre Kernfunktion zu fokussieren. Gleichzeitig sollten das Grundprinzip "Faire Bezahlung für gute Arbeit" und die Sozialpartnerschaft in Deutschland gestärkt werden. Im Fokus der Untersuchung standen hierbei die Neuregelungen zur Überlassungshöchstdauer sowie die Regelungen zu Equal Pay und den Abweichungsmöglichkeiten hiervon. Ebenfalls umfassend betrachtet wurden die Offenlegungs-, Konkretisierungs- und Informationspflicht sowie die Stärkung der Tarifautonomie, das Streikbrecherverbot, die Regelungen zur Mitbestimmung und die Festhaltenserklärung