Preemptive Behavior in Sequential-Move Tournaments with Heterogeneous Agents

Rank-order tournaments are usually modeled simultaneously. However, real tournaments are often sequential. We show that agents’ strategic behavior in sequential-move tournaments significantly differ from the one in simultaneous-move tournaments: In a sequential-move tournament with heterogeneous agents, there may be either a first-mover or a second-mover advantage. Under certain conditions the first acting agent chooses a preemptively high effort so that the following agent gives up. The principal is able to prevent preemptive behavior in equilibrium, but he will not implement first-best efforts although the agents are risk neutral.preemption, tournaments

grofit: Fitting Biological Growth Curves with R

The grofit package was developed to fit many growth curves obtained under different conditions in order to derive a conclusive dose-response curve, for instance for a compound that potentially affects growth. grofit fits data to different parametric models and in addition provides a model free spline method to circumvent systematic errors that might occur within application of parametric methods. This amendment increases the reliability of the characteristic parameters (e.g.,lag phase, maximal growth rate, stationary phase) derived from a single growth curve. By relating obtained parameters to the respective condition (e.g.,concentration of a compound) a dose response curve can be derived that enables the calculation of descriptive pharma-/toxicological values like half maximum effective concentration (EC50). Bootstrap and cross-validation techniques are used for estimating confidence intervals of all derived parameters.

Liquid Crystal Mixed Beam-Switching and Beam-Steering Network in Hybrid Metallic and Dielectric Waveguide Technology

Future communication systems at W-band are demanding highly directive antenna systems with beam-steering capability. For the hardware implementation of analogue beam-steering at millimetre waves, the microwave liquid crystal (LC) technology is ideally suited. It takes advantage of specifically synthesised LCs for microwaves in combination with appropriate device and biasing concepts, where the orientation of the LC, and therefore, its effective permittivity can be continuously tuned. It has low dielectric losses above 10GHz with a decreasing trend with increasing frequency. To exploit these unique characteristics, the focus of this scientific work is set for the first time on the investigation of an LC-based network with mixed discrete beam-switching and continuous beam-steering capability between the switching states for high-gain antennas at W-band. It consists of a Butler matrix combined with continuously tuneable phase shifters and a novel type of RF switch, an interference-based Single-Pole n-Throw (SPnT). The interference principle of the SPnT allows a continuously adjustable power splitting ratio, and hence, the generation of multiple beams. Different technologies are investigated for the realisation of this mixed network. Due to its high level of integrability and compact designs, the standard low temperature co-fired ceramic technology is examined, however, for a first proof-of-concept at Ka-band only. For W-band, two low-loss technologies are investigated: tuneable metallic and dielectric waveguides. While metallic waveguides are well suited for the realisation of low-loss non-tuneable feeding networks, dielectric waveguides are better suited for the realisation of tuneable LC components at (sub)millimetre waves, since no metallic boundaries are limiting the integration of an electrical biasing network. As non-tuneable core part, a Butler matrix with an average insertion loss of 3.5 dB at 102 GHz is realised, which is based on a novel multifunctional crossover design, allowing a miniaturised in-plane realisation of the overall mixed network. As key component for tuning of the mixed beam-switching and beam-steering network, a step-index dielectric waveguide phase shifter is presented. With a phase shifter figure-of-merit of 100 °/dB at 102 GHz, this fully electrically biased phase shifter is going far beyond the state-of-the-art for electrically tuneableW-band phase shifter. To stay on the same technology platform and to allow an in-plane realisation from the input port up to the radiating elements, the interference-based SPnTs are additionally investigated by a hybrid implementation of metallic and dielectric waveguides. It exhibits an insertion loss of 3dB, while providing an isolation of 27 dB. Hence, this hybrid metallic and dielectric waveguide technology reveals a high potential not only for the presented LC-based mixed beam-switching and beam-steering network, but also for LC-tuned continuous beam-steering networks at frequencies above 100 GHz, since low-loss metallic waveguide feeding networks can be generally combined with high-performance tuneable dielectric waveguides

Marine nanogels as a source of atmospheric nanoparticles in the high Arctic

The high Arctic (north of 80°N) in summer is a region characterized by clean air and low abundances of preexisting particles. Marine colloidal nanogels i.e., assembled dissolved organic carbohydrate polymer networks have recently been confirmed to be present in both airborne particles and cloud water over the Arctic pack ice area. A novel route to atmospheric nanoparticles that appears to be operative in the high Arctic is suggested. It involves the injection of marine granular nanogels into the air from evaporating fog and cloud droplets, and is supported by observational and theoretical evidence obtained from a case study. Statistical analysis of the aerosol size distribution data recorded in the years 1991, 1996, 2001, and 2008 classified 75 nanoparticle events - covering 17% of the observed time period - as nanogel-type events, characterized by the spontaneous appearance of several distinct size bands below 200 nm diameter

Impact and risk analysis in the integrated development of product and production system

The assessment of risks and influences of engineering changes of a product or production system on affected technical (sub-) systems of the same or a different domain are of great importance in order to evaluate possible alternatives and to select solutions. The increasing complexity of mechatronic products and production systems with Industry 4.0 technology reinforces the demand for a method that supports engineers in decision making in both technical and strategic issues. By using the method presented in this contribution, interdependencies between product functions, product features and the corresponding production processes and machines can be modelled and used to estimate the impact and risks of changes in one of those domains. Using the method, the change propagation of variations in and between the domains can be evaluated. The objective of the method is to support decision making in different use-cases like integrated product- and production system development, product variations while carrying over most of the production system or varying production processes while carrying over the product to improve production key performance indicators (KPI). Based on the model of PGE – Product Generation Engineering, the information of the reference system is used to identify the interdependencies. The inclusion of strategic factors like know-how and costs is implemented in the model, as well as the quantity and type of variations. The method consists of a representative model for a quick, holistic overview about the interdependencies and of a tool based model by using Model-Based Systems Engineering (MBSE) for an automatic connection and evaluation of the data. The contribution is part of the project I4TP - Sino German Industry 4.0 Factory Automation Platform (i4tp.org), in which a platform is developed to automatically configure a turnkey production system for a product in development

The first plastid genome of the Holoparasitic Genus Prosopanche (Hydnoraceae)

Plastomes of parasitic and mycoheterotrophic plants show different degrees of reduction depending on the plants' level of heterotrophy and host dependence in comparison to photoautotrophic sister species, and the amount of time since heterotrophic dependence was established. In all but the most recent heterotrophic lineages, this reduction involves substantial decrease in genome size and gene content and sometimes alterations of genome structure. Here, we present the first plastid genome of the holoparasitic genus Prosopanche, which shows clear signs of functionality. The plastome of Prosopanche americana has a length of 28,191 bp and contains only 24 unique genes, i.e., 14 ribosomal protein genes, four ribosomal RNA genes, five genes coding for tRNAs and three genes with other or unknown function (accD, ycf1, ycf2). The inverted repeat has been lost. Despite the split of Prosopanche and Hydnora about 54 MYA ago, the level of genome reduction is strikingly congruent between the two holoparasites although highly dissimilar nucleotide sequences are observed. Our results lead to two possible evolutionary scenarios that will be tested in the future with a larger sampling: 1) a Hydnoraceae plastome, similar to those ofHydnora and Prosopanche today, existed already in the most recent common ancestor and has not changed much with respect to gene content and structure, or 2) the genome similarities we observe today are the result of two independent evolutionary trajectories leading to almost the same end point. The first hypothesis would be most parsimonious whereas the second would point totaxon dependent essential gene sets for plants released from photosynthetic constraints.Fil: Jost, Matthias. Technische Universität Dresden.; AlemaniaFil: Naumann, Julia. Technische Universität Dresden.; AlemaniaFil: Rocamundi, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cocucci, Andrea Aristides. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Wanke, Stefan. Technische Universität Dresden.; Alemani

Discordant phylogenomic placement of Hydnoraceae and Lactoridaceae within Piperales using data from all three genomes

Original ResearchPhylogenetic relationships within the magnoliid order Piperales have been studied extensively, yet the relationships of the monotypic family Lactoridaceae and the holoparasitic Hydnoraceae to the remainder of the order remain a matter of debate. Since the first confident molecular phylogenetic placement of Hydnoraceae among Piperales, different studies have recovered various contradictory topologies. Most phylogenetic hypotheses were inferred using only a few loci and have had incomplete taxon sampling at the genus level. Based on these results and an online survey of taxonomic opinion, the Angiosperm Phylogeny Group lumped both Hydnoraceae and Lactoridaceae in Aristolochiaceae; however, the latter family continues to have unclear relationships to the aforementioned taxa. Here we present extensive phylogenomic tree reconstructions based on up to 137 loci from all three subcellular genomes for all genera of Piperales. We infer relationships based on a variety of phylogenetic methods, explore instances of phylogenomic discordance between the subcellular genomes, and test alternative topologies. Consistent with these phylogenomic results and a consideration of the principles of phylogenetic classification, we propose to exclude Hydnoraceae and Lactoridaceae from the broad circumscription of Aristolochiaceae, and instead favor recognition of four monophyletic and morphologically well circumscribed families in the perianth-bearing Piperales: Aristolochiaceae, Asaraceae, Hydnoraceae, and Lactoridaceae, with a total of six families in the orderinfo:eu-repo/semantics/publishedVersio

New insights in sources of the sub-micrometre aerosol at Mt. Zeppelin observatory (Spitsbergen) in the year 2015

In order to evaluate the potential impact of the Arctic anthropogenic emission sources it is essential to understand better the natural aerosol sources of the inner Arctic and the atmospheric processing of the aerosols during their transport in the Arctic atmosphere. A 1-year time series of chemically specific measurements of the sub-micrometre aerosol during 2015 has been taken at the Mt. Zeppelin observatory in the European Arctic. A source apportionment study combined measured molecular tracers as source markers, positive matrix factorization, analysis of the potential source distribution and auxiliary information from satellite data and ground-based observations. The annual average sub-micrometre mass was apportioned to regional background secondary sulphate (56%), sea spray (17%), biomass burning (15%), secondary nitrate (5.8%), secondary marine biogenic (4.5%), mixed combustion (1.6%), and two types of marine gel sources (together 0.7%). Secondary nitrate aerosol mainly contributed towards the end of summer and during autumn. During spring and summer, the secondary marine biogenic factor reached a contribution of up to 50% in some samples. The most likely origin of the mixed combustion source is due to oil and gas extraction activities in Eastern Siberia. The two marine polymer gel sources predominantly occurred in autumn and winter. The small contribution of the marine gel sources at Mt. Zeppelin observatory in summer as opposed to regions closer to the North Pole is attributed to differences in ocean biology, vertical distribution of phytoplankton, and the earlier start of the summer season