Glacial/interglacial changes in mineral dust and sea-salt records in polar ice cores: sources, transport, and deposition

Sea salt and mineral dust records as represented by Na+ and Ca2+ concentrations, respectively, in Greenland and Antarctic ice cores show pronounced glacial/interglacial variations. For the Last Glacial Maximum (LGM) mineral dust (sea salt) concentrations in Greenland show an increase of a factor of approximately 80 (15) compared to the Holocene and significant shifts by a factor of 15 (5) during Dansgaard Oeschger events. In Antarctica, the dust (sea salt) flux is enhanced by a factor of 15 (3) during the LGM compared to the Holocene and variations by approximately a factor of 8 (1-2) exist in parallel to Antarctic warm events. Primary glacial dust sources are the Asian deserts for Greenland and Patagonia for Antarctica. Ice core evidence and model results show that both changes in source strength as well as atmospheric transport and lifetime contributed to the observed changes in Greenland ice cores. In Antarctica changes in ice core fluxes are in large parts related to source variations both for sea salt and dust, where the formation of sea salt aerosol from sea ice may play a pivotal role. Summarizing our latest estimates on changes in sources, transport and deposition these processes are roughly able to explain the glacial increase in sea salt in both polar regions while they fall short by at least a factor of 4-7 for mineral dust. Future improvements in model resolution and in the formulation of source and transport processes together with new ice core records, e.g. on dust size distributions, will eventually allow to converge models and observations

MutationDistiller: user-driven identification of pathogenic DNA variants

MutationDistiller is a freely available online tool for user-driven analyses of Whole Exome Sequencing data. It offers a user-friendly interface aimed at clinicians and researchers, who are not necessarily bioinformaticians. MutationDistiller combines Mutation- Taster’s pathogenicity predictions with a phenotypebased approach. Phenotypic information is not limited to symptoms included in the Human Phenotype Ontology (HPO), but may also comprise clinical diagnoses and the suspected mode of inheritance. The search can be restricted to lists of candidate genes (e.g. virtual gene panels) and by tissue-specific gene expression. The inclusion of GeneOntology (GO) and metabolic pathways facilitates the discovery of hitherto unknown disease genes. In a novel approach, we trained MutationDistiller’s HPO-based prioritization on authentic genotype–phenotype sets obtained from ClinVar and found it to match or outcompete current prioritization tools in terms of accuracy. In the output, the program provides a list of potential disease mutations ordered by the likelihood of the affected genes to cause the phenotype. MutationDistiller provides links to gene-related information from various resources. It has been extensively tested by clinicians and their suggestions have been valued in many iterative cycles of revisions. The tool, a comprehensive documentation and examples are freely available at https://www.mutationdistiller.org

White Organic Light-Emitting Diodes with fine chromaticity tuning via ultrathin layer position shifting

Non-doped white organic light-emitting diodes using an ultrathin yellow-emitting layer of rubrene (5,6,11,12-tetraphenylnaphtacene) inserted on either side of the interface between a hole-transporting NPB (4,4'-bis[N-(1-naphtyl)-N-phenylamino]biphenyl) layer and a blue-emitting DPVBi (4,4'-bis(2,2'-diphenylvinyl)-1,1'-biphenyl) layer are described. Both the thickness and the position of the rubrene layer allow fine chromaticity tuning from deep-blue to pure-yellow via bright-white with CIE coordinates (x= 0.33, y= 0.32), a external quantum efficiency of 1.9%, and a color rendering index of 70. Such a structure also provides an accurate sensing tool to measure the exciton diffusion length in both DPVBi and NPB (8.7 and 4.9 nm respectively)

Micro- and Macroscopic Modeling of Crowding and Pushing in Corridors

Experiments with pedestrians revealed that the geometry of the domain, as well as the incentive of pedestrians to reach a target as fast as possible have a strong influence on the overall dynamics. In this paper, we propose and validate different mathematical models at the micro- and macroscopic levels to study the influence of both effects. We calibrate the models with experimental data and compare the results at the micro -- as well as macroscopic levels. Our numerical simulations reproduce qualitative experimental features on both levels, and indicate how geometry and motivation level influence the observed pedestrian density. Furthermore, we discuss the dynamics of solutions for different modeling approaches and comment on the analysis of the respective equations.Comment: 22 pages, 14 figure

The dynamics of volunteer motivations for engaging in the management of invasive plants : Insights from a mixed-methods study on Scottish seabird islands

Acknowledgments The authors thank the SOS Puffin volunteers and the Craigleith Management Group for their support in this research project. We also thank John Hunt (SOS Puffin), Anja Byg and Kerry Waylen (The James Hutton Institute), Norman Dandy (Plunkett Foundation), Michelle Pinard (University of Aberdeen), and four anonymous reviewers for their valuable comments on earlier versions of this paper. We acknowledge funding by the Natural Environment Research Council and the Rivers and Fisheries Trusts of Scotland. (NERC).Peer reviewedPostprin

Online monitoring of yeast cultivation using a fuel-cell-type activity sensor

A microbial fuel-cell type activity sensor integrated into 500mL and 3.2L bioreactors was employed for ampero- (μA) and potentiometric (mV) measurements. The aim was to follow the microbial activity during ethanol production by Saccharomyces cerevisiae and to detect the end of carbohydrate consumption. Three different sensor setups were tested to record electrochemical signals produced by the metabolism of glucose and fructose (1:1) online. In a first setup, a reference electrode was used to record the potentiometric values, which rose from 0.26 to 0.5V in about 10h during the growth phase. In a second setup, a combination of ampero- and pseudo-potentiometric measurements delivered a maximum voltage of 35mV. In this arrangement, the pseudo-potentiometric signal changed in a manner that was directly proportional to the amperometric signals, which reached a maximum value of 32μA. In a third type of arrangement, a reference electrode was added to the anodic bioreactor compartment to carry out ampero- and potentiometric measurements; this is made possible by the high internal resistance of the cultivation. In this case, the reference potential rose to 0.44V while the current maximum recorded by the working electrodes reached 27μA. Reference and pseudo-reference electrodes were in all cases K3Fe(CN)6/carbon. Electrodes were made of 9cm2 woven graphite. To compare the electrochemical signals with established values, the metabolism was also monitored for optical density (at 600nm) indicating biomass production. For fructose and glucose conversion, HPLC with an Aminex column and RI detector was used, and ethanol production was analyzed by GC with methanol as internal standard. The combination of amperometric and potentiometric recordings was found to be an ideal setup and was successfully used in reproducible cultivation

'n Ondersoek na die behoeffes van studentverpleegkundiges met betrekking tot die ontwikkeling van basiese studievaardighede.

>Magister Scientiae - MScDie grondgedagte vir hierdie studie spruit voort uit die verantwoordelikheid van die verpleegdosente om die vermoëns van studentverpleegkundiges tot selfgerigte studie te ontwikkel. Selfgerigte studie vereis onder andere, die vermoë om inligting te kan vind, te verwerk, en toe te pas in die praktyk. Hierdie vaardighede is essensiële voorvereistes vir onafhanklike professionele praktisering. Die ontwikkeling van die genoemde vaardighede impliseer 'n multi-dimensionele benadering wat die student in totaliteit aanspreek. Voorts vereis dit nougesette betrokkenheid van die student by sy/ haar studies. Laasgenoemde veronderstel, onder andere, egter dat studente oor sekere essensiële vaardighede, in verband met leer en studie, beskik. Uit die literatuur blyk dit duidelik dat sekondêre onderwys, oor die algemeen, studente nie voldoende voorberei vir tersiêre onderwys nie. Deur middel van hierdie studie wou die navorser dus antwoorde probeer vind op die vraag of studenteverpleegkundiges behoeftes ervaar aan leiding met betrekking tot spesifiek geïdentifiseer studievaardighede, die leiding wat verskaf word en of daar leemtes bestaan in die leiding wat studente reeds ontvang. Nadat die studieterrein afgebaken is, is verskillende terme en begrippe, grondliggend tot die studie, omskryf en in perspektief gestel. Hoofstuk twee is gewyaan 'n bespreking van die konsepte leer, -probleme en studie binne die perspektief van hierdie studie, asook verbandhoudend relevante begrippe. Aandag is in die daaropvolgende twee hoofstukke geskenk aan, onderskeidelik, spesifieke stud ievaardighede verbandhoudend tot die versameling van inligting en studievaardighede verbandhoudend tot die benutting van inligting

Seasonal variability of resources : The unexplored adversary of biogas use in rural Ethiopia

Funding This project was funded by (BBSRC BB/M010996/1) and the University of Aberdeen. AF’s contribution was supported by UKRI (ES/P002501/1). JS’s contribution was supported by UKRI (ES/P002501/1) and DFID NEXUS (NE/P004830). Acknowledgements We would like to thank Hawassa University and the Southern Agricultural Research Institute for their support with organisation, data collection and translation.Peer reviewedPublisher PD