Sidewall depletion in nano-patterned LAO/STO heterostructures

We report the fabrication of nanostructures from the quasi-two-dimensional electron gas (q2DEG) formed at the LaAlO$_{3}$/ SrTiO$_{3}$ (LAO/STO) interface. The process uses electron beam lithography in combination with reactive ion etching. This technique allows to pattern high-quality structures down to lateral dimensions as small as $100$nm while maintaining the conducting properties without inducing conductivity in the STO substrate. Temperature dependent transport properties of patterned Hall bars of various widths show only a small size dependence of conductivity at low temperature as well as at room temperature. The deviation can be explained by a narrow lateral depletion region. All steps of the patterning process are fully industry compatible.Comment: 5 pages, 4 figure

The Holocene thermal maximum in the Nordic Seas: the impact of Greenland Ice Sheet melt and other forcings in a coupled atmosphere-sea ice-ocean model

The relatively warm early Holocene climate in the Nordic Seas, known as the Holocene Thermal Maximum (HTM), is often associated with an orbitally forced summer insolation maximum at 10 ka BP. The spatial and temporal response recorded in proxy data in the North Atlantic and the Nordic Seas reveal a complex interaction of mechanisms active in the HTM. Previous studies have investigated the impact of the Laurentide Ice Sheet (LIS), as a remnant from a previous glacial period, altering climate conditions with a continuous supply of melt water to the Labrador Sea and adjacent seas and with a downwind cooling effect from the remnant LIS. In our present work we extend this approach by investigating the impact of the Greenland Ice Sheet (GIS) on the early Holocene climate and the HTM. Reconstructions suggest melt rates of 13 mSv for 9 ka BP, which result in our model in a ocean surface cooling of up to 2 K near Greenland. Reconstructed summer SST gradients agree best with our simulation including GIS melt, confirming that the impact of early Holocene GIS is crucial for understanding the HTM characteristics in the Nordic Seas area. This implies that the modern and near-future GIS melt can be expected to play an active role in the climate system in the centuries to come

The impact of early Holocene Arctic Shelf flooding on climate in an atmosphere–ocean–sea–ice model

Glacial terminations are characterized by a strong rise in sea level related to melting ice sheets. This rise in sea level is not uniform all over the world, because regional effects (uplift and subsidence of coastal zones) are superimposed on global trends. During the early Holocene the Siberian Shelf became flooded before 7.5 ka BP and the coastline reached modern-day high stands at 5 ka BP. This area is currently known as a sea-ice production area and contributes significantly to the sea-ice exported from the Arctic through the Fram Strait. This leads to the following hypothesis: during times of rising sea levels, shelves become flooded, increasing sea-ice production on these shelves, increasing sea-ice volume and export through the Fram Strait and causing the sea-ice extent to advance in the Nordic Seas, yielding cooler and fresher sea surface conditions. We have tested this hypothesis in an atmosphere–ocean–sea–ice coupled model of intermediate complexity (LOVECLIM). Our experiment on early Holocene Siberian Shelf flooding shows that in our model sea-ice production in the Northern Hemisphere increases (15%) and that sea-ice extent in the Northern Hemisphere increases (14%) but sea-ice export decreases (−15%) contrary to our hypothesis. The reason of this unexpected behaviour has its origin in a weakened polar vortex, induced by the land–ocean changes due to the shelf flooding, and a resulting decrease of zonality in the Nordic Seas pressure regime. Hence the winter Greenland high and the Icelandic low strengthen, yielding stronger winds on both sides of the Nordic Seas. Increased winds along the East Greenland Current support local sea-ice production and transport towards the South, resulting in a wider sea-ice cover and a southward shift of convection areas. The overall strength of the Atlantic meridional overturning circulation is reduced by 4% and the heat transport in the Atlantic basin by 7%, resulting in an annual cooling pattern over the Nordic Seas by up to −4 °C. We find that the flooding of the Siberian shelf resulting from an orbitally induced warming and related glacioeustatic sea level rise causes a Nordic Seas cooling feedback opposed to this warming

Associations between stress and migraine and tension-type headache: Results from a school-based study in adolescents from grammar schools in Germany

Introduction: Stress is considered the major contributor to migraine and tension-type headache in adolescents. Previous studies have focused on general stressors, whereas the aim of the present study was to investigate associations between individuals’ stressful experiences and different types of headache. Methods: Adolescents from 10th and 11th grades of grammar schools filled in questionnaires. Stressful experiences were measured with the Trier Inventory of Chronic Stress. Type of headache was classified according to the International Classification of Headache Disorders. Linear regressions, adjusted for sex and grade, were calculated to estimate differences in stress scores that can be attributed to migraine, tension-type headache or miscellaneous headache. Results: A total of 1260 questionnaires were analysed. Tension-type headache, migraine and co-existing migraine plus tension-type headache were found in 48.7%, 10.2% and 19.8% of the participants. In subjects with migraine or co-existing migraine plus tension-type headache, high increases in stress scores were found in all investigated dimensions, whereas much weaker and inconsistent associations were found in subjects with tension-type headache only. Conclusions: The characteristic of migraine is more associated with stressful experiences than this is the case for tensiontype headache. This suggests that adolescent migraine patients might specially benefit from behavioural interventions regarding stress

Concurrent TNFRSF1A R92Q and pyrin E230K mutations in a child with multiple sclerosis

We report a 16-year-old female patient with a severe course of multiple sclerosis and concomitant symptoms suggestive of a hereditary autoinflammatory disease. Genetic analyses revealed that she inherited a TNFRSF1A R92Q mutation from her mother and a pyrin E230K mutation from her father. To our knowledge, this is the first report of a patient with severe childhood multiple sclerosis and mutations in two genes which predispose to hereditary autoinflammatory disorders. We speculate that these mutations contribute to early multiple sclerosis manifestation and enhance the inflammatory damage inflicted by the autoimmune response

Digital Soil Mapping auf unterschiedlichen Skalen unter Anwendung von Techniken des maschinellen Lernens und multivariater Geostatistik im Mittelmeerraum

This dissertation aims at creating digital soil mapping approaches to model soil textural fractions at the field and catchment scale in Mediterranean soil types. It intends to improve the prediction accuracy of soil spatial interpolation models by focusing on (i) the combination of traditional kriging methods with more complex, data-driven machine learning algorithms, and (ii) the integration of environmental covariates from geophysical sensor data. In addition, model outputs are delivered by a web-based dissemination platform (geoportal) as well as in form of a Web Map Service to advance the long-term visibility and access to digital soil mapping data.Das Ziel dieser Dissertation ist es, geeignete Digital Soil Mapping-Ansätze zu entwickeln, um Korngrößenfraktionen mediterraner Böden auf der Feld- und Landschaftsskala zu modellieren. Dabei geht es primär um eine verbesserte Vorhersagegenauigkeit räumlicher Interpolationsverfahren (i) durch Kombinieren traditioneller Kriging-Methoden mit komplexeren, datengetriebenen Modellen des Maschinellen Lernens sowie (ii) durch die Berücksichtigung geophysikalischer Prädiktoren. Darüber hinaus werden die erstellten Karten über ein Geoportal und in Form eines WMS-Dienstes weitergegeben, um eine langfristige und breite Erreichbarkeit der Digital Soil Mapping-Daten zu gewährleisten

Protein enrichment of cassava peel by submerged fermentation with Trichoderma viride (ATCC 36316)

Cassava (Manihot esculenta Crantz) peel is one of the solid wastes produced as a consequence of cassava processing. It is low in protein but contains a large amount of carbohydrate, causing an environmental problem with disposal. In order to add-value to this major cassava processing waste and also reduce its resultant environmental pollution, this study investigated the effect of submerged fermentation using Trichoderma viride ATCC 36316 on the protein content and amino acid profile of enzyme and non-enzyme pre-treated cassava peel. Compositional analysis of the product obtained with T. viride in the fermentor revealed that dry biomass increased in crude protein, true protein, crude fat, crude fibre, ash and total dietary fibre. The crude protein increased from 4.21 to 37.63 and 36.52% for enzyme and non-enzyme pre-treated fermented samples respectively with 31.6% as true protein for the former and 29.03% as true protein for the latter while the starch contents reduced considerably in both samples. Starch reduction was from 51.93 to 24.34 and 26.07% for enzyme and non-enzyme pre-treated fermented samples, respectively. The fermented products contained all the essential amino acids; however the chemical score of essential amino acids indicated methionine as the limiting amino acid