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opencc-by-4.0Mar 2022View details →

Trajectories and driving profiles for hybrid h2 multiple units.

Identifier: DOI Creator: German Aerospace Center, Institute of Vehicle Concepts nameType: Organizantional Title: Trajectories and driving profiles for hybrid h2 multiple units. Publisher: Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Institut für Fahrzeugkonzepte. Publication Year: 2022 ResourceType: Simulated Trajectories Subject: This data set comprises driving profiles and simulated trajectories for bi-mode fuel cell hydrogen multiple units. Date: 2022-02-10 Description: This data set comprises driving profiles and simulated trajectories for bi-mode fuel cell hydrogen multiple units. Methodology is described in relatedItem. FundingReference: FCH2Rail; Fuel Cell Hybrid Power Pack for Rail Applications; Grant Agreement Number: 101006633 RelatedItem: "D1.1 - Report on line and use case based requirements" of the FCH2Rail project. This dataset comprises following files: characteristic_traction_curve.csv Resembles the maximum force applicable by the electric engine at a given velocity to accelerate the train. Velocity is given in kilometer per hour [km/h], traction_force is given in newton [N]. characteristic_maximal_electrical_breaking_curve.csv Resembles the maximum force applicable by the electric engine at a given velocity to decelerate the train. Velocity is given in kilometer per hour [km/h], max_elec_braking_force is given in newton [N]. characteristic_maximal_mechanical_breaking_curve.csv Resembles the maximum force applicable by the mechanical brake at a given velocity to decelerate the train. Velocity is given in kilometer per hour [km/h], max_mech_braking_force is given in newton [N]. electrifications.csv Electrifications are derived from open street map (OSM). pkm resembles distances from start in kilometers. Electrification: 1 = electrified, 0 = not electrified. maxspeeds.csv pkm resembles distances from start in kilometers. Maxspeeds are derived from Open Street Map data. Data gaps are manually corrected with infrastructure maps from Adif. Maxspeeds in km/h. slopes.csv pkm resembles distances from start in kilometers. Slopes in permille are derived from JAXA ALOS 0.1 X 0.1 DEM. Underlying method is described in the public deliverable "D1.1 - Report on line and use case based requirements" of the FCH2Rail project. timetable.csv pkm resembles distances from start in kilometers. station_name represents common name of railway stations where the train stops. standing_time [s] resembles the standing time within the station in seconds. driving_time [s] resembles driving time to the next station in seconds. vehicle.csv Contains the descriptive values for the vehicle. Vehicle resembles the name of the train to which the corresponding  values are assigned. Static_mass is specified in kilogram [kg], rotating_mass is specified in kilogram [kg]. Davis coefficient davis_a is specified in newton [N], davis_b is specified in newton per kilometers per hour [N/(km/h)] & davis_c is specified in newton per squared kilometers per hour [N/(km/h)^2].   simulated_trajectory.csv Underlying simulation method, with which simulated trajectory is obtained is described in the public deliverable "D1.1 - Report on line and use case based requirements" of the FCH2Rail project. Traveltime is specified in seconds, starts with zero. Traveled distance is specified in meters [m]. Velocity is specified in meters per second [m/s].  Power at the wheel is specified in watt [W].

opencc-zeroMay 2022View details →

Asymmetric song recognition does not influence gene flow in an emergent songbird hybrid zone

Hybrid zones can be used to examine the mechanisms affecting reproductive isolation and speciation, like song. Song has equivocal support as a driver of speciation; we did not find song to cause reproductive isolation. We examined an emerging secondary contact zone between White-crowned Sparrow subspecies pugetensis and gambelii by measuring song variation, song recognition, plumage, morphology and mtDNA. Plumage and morphological characters provided evidence of hybridization in the contact zone, with some birds possessing plumage and song characteristics intermediate between the subspecies. Playback experiments revealed asymmetric song recognition: male pugetensis displayed greater response to their own song than gambelii song, whereas gambelii did not discriminate significantly. If female choice operates similarly to male song discrimination, we predicted asymmetric gene flow, resulting in a greater number of hybrids with gambelii mitochondrial DNA (mtDNA). Contrary to our prediction, more gambelii and putative hybrids in the contact zone possessed pugetensis mtDNA haplotypes, possibly due to greater pugetensis abundance and female-biased dispersal.

opencc-zeroDec 2021View details →

Hybrid evolution repeats itself across environmental contexts in Texas sunflowers (Helianthus)

To what extent is evolution repeatable? Little is known about whether the evolution of hybrids is more (or less) repeatable than non-hybrids. We used field experimental evolution in annual sunflowers (Helianthus) in Texas to ask the extent to which hybrid evolution is repeatable across environments compared to non-hybrid controls. We created hybrids between Helianthus annuus (L.) and H. debilis (Nutt.) and grew plots of both hybrids and non-hybrid controls through eight generations at three sites in Texas. We collected seeds from each generation and grew each generation × treatment × home site combination at two final common gardens. We estimated the strength and direction of evolution in terms of fitness and 24 traits, tested for repeated versus non-repeated evolution, and assessed overall phenotypic evolution across lineages and in relation to a locally adapted phenotype. Hybrids consistently evolved higher fitness over time while controls did not, though trait evolution varied in strength across home sites. Repeated evolution was more evident in hybrids versus non-hybrid controls, and hybrid evolution was often in the direction of the locally adapted phenotype. Our findings have implications for both the nature of repeatability in evolution and the contribution of hybridization to evolution across environmental contexts.

opencc-by-4.0May 2022View details →

Using a Hybrid Kano-Importance Questionnaire in the Acquisition of Data Related to Students' Expectations from Online Educational Platforms

This dataset contains the data collected for the assessment of the quality attributes of a new online educational platform. The questionnaire used for data collection the Kano methodology and was designed as a hybrid Kano-importance questionnaire. The purpose of this data collection consists of the analysis of the students’ expectations regarding the features proposed for a new online educational platform. This analysis facilitates the identification of student needs during times of COVID-19 pandemic and post-pandemic times, while a transition to an online educational system was used throughout the world.

opencc-by-4.0Jul 2019View details →

Manufacturing of Hybrid Overmoulded FRP Components: Impact of Process and Environmental Parameters on the Mechanical Properties

A manufacturing parametric study was carried out on a hybrid part, consisting of two organo sheets and injection moulded rib reinforcements, made out of a short fibre reinforced plastic. The effect of the temperature of all components, the pressure profile throughout the injection moulding process as well as the subsequent storage conditions on the mechanical properties was investigated. For this purpose a total of 96 parts was manufactured with different processing parameter combinations. Afterwards all parts were subjected to a cantilever beam test, analysing initial stiffness, deformation work and peak force. Furthermore a variety of potentially influencing factors such as temperature, humidity, order of testing, transfer durations and many more were tracked. Parameter definition: <ul> <li>part_ID: Unique part identifier.</li> <li>OS-degradation: Degradation of the organo-sheet(OS) because of thermal decomposition at temperatures above 260°C. Given as percentage of degraded mass.</li> <li>heating-duration: Time of heating the OS in seconds.</li> <li>heating_temperature-OS: Surface temperature of the OS at the end of the heating period in °C.</li> <li>heating_field-temp.: Temperature of the heating field immediately before the heating process begins in °C.</li> <li>stiffness: Bending stiffness of the structure in N/mm. Determined from the force-deflection-curve between 50 and 150 N.</li> <li>maximum_force: Highest force value measured during the cantilever beam test in kN.</li> <li>deflection: Value corresponding to the maximum force in mm.</li> <li>deformation_work: Absorbed work due to deformation in kN*mm. Determined by integrating the force-deflection-curve from 5 to 30 mm with a lower bound of 0.05 kN on the force.</li> <li>corrected-x: Value of x corrected by taking into account the water intake.</li> <li>rib_lengths-x: Length of the rib in mm (1à5th, 2à7th , 3à10th).</li> <li>sprue_width: Diameter of the sprue in mm.</li> <li>part_length: Total part length in mm.</li> <li>mould_filled-x: Flag indicating whether the mould was filled (indicated by 1) at position x (1àbroad end, 2àmid, 3ànarrow end)</li> <li>rib_length: Mean of the measured rib lengths in mm.</li> <li>mould_filled: Mean of the flags for fill state.</li> <li>day_of_testing: Day on which the part was tested (1,2,3).</li> <li>no._of_test_per_day: Number of test on the respective day.</li> <li>no._of_test_total: Number of tests in total.</li> <li>delay_of_transfer: Duration between removal of the OS from the heating field and begin of the transfer in s.</li> <li>transfer_temp_beg.-x: Surface temperature in °C of the OS at the beginning of the transfer at position x.</li> <li>transfer_temp_end-x: Surface temperature in °C of the OS at the end of the transfer at position x.</li> <li>tool_surface_temp.-x: Surface temperature in °C of the tool at position x.</li> <li>fixing-x: Flag indicating whether the OS was fixed (indicated by 1) at position x (1àbroad end, 2àmid, 3ànarrow end).</li> <li>fixing: Mean of the flags for fixing.</li> <li>duration-rapid_traverse: Duration of the rapid motion phase of the press in s.</li> <li>duration-deformation: Duration of the motion phase of the press deforming the OS in s.</li> <li>press_profile: ID for translational velocity of the press (0àslow, 1àfast).</li> <li>duration-closing: Sum of duration-rapid_traverse and duration-deformation.</li> <li>duration-injection: Duration of the pure injection process in s.</li> <li>duration-holding_pressure: Time for which the holding pressure was kept up in s.</li> <li>temp.-cylinder-x: Mean of the temperature over one cycle at one heating band in °C.</li> <li>temp-hot_runner-x: Mean of the temperature over one cycle at one heating element in the hot runner in °C.</li> <li>temp.-defl._tool-x: Mean of the temperature over one cycle in the deflection tool at position x.</li> <li>delay-injection: Time between the press fully closing and the beginning of injection in s.</li> <li>holding_pressure-beg.-x: Holding pressure at the beginning of holding and position x in bar.</li> <li>holding_pressure-end-x: Holding pressure at the ned of holding and position x in bar.</li> <li>duration-form_stability-x: Time in s between maximum melt pressure and form stability, characterised by a pressure below 75 bar.</li> <li>max.-pressure-melt-x: Maximum pressure during the injection process at position x in bar.</li> <li>transmission-hold._press.-beg.: Ratio of pressure signal from the sensor at screw and in tool at beginning of holding.</li> <li>transmission-hold._press.-end: Ratio of pressure signal from the sensor at screw and in tool at end of holding.</li> <li>cooling_rate-hold._press.-x: Measured cooling rate at position x during the holding phase in °C/s.</li> <li>cooling_rate-cooling-x: Measured cooling rate at position x during the cooling phase in °C/s.</li> <li>tool-temp.-x: Measured tool temperature at position x in °C.</li> <li>max.-melt-temp-x: Highest measured melt temperature at position x in °C.</li> <li>demoulding-temp.-x: Measured tool temperature at position x at demoulding in °C.</li> <li>storage-standard_atmosphere: Storage duration at standard atmosphere in h.</li> <li>absoprtion_water-std.atm.: Water absorption during the storage at standard atmosphere in g.</li> <li>absoprtion_water-climate_chamber.: Water absorption during the storage in the climate chamber in g.</li> <li>storage-climate_chamber: Storage duration in climate chamber in h.</li> <li>vert._position-climate_chamber: Vertical position in the climate chamber in cm.</li> <li>air-temp.: Air temperature during manufacturing in °C.</li> <li>air-rel._humidity: Relative humidity during manufacturing in %.</li> <li>no.-production-day: Consecutive number indicating parts manufactured before the respective part.</li> <li>factor_level: Factor level in the DOE.</li> <li>prod.-date: Date of production.</li> <li>prod-time: Time of production in CEST.</li> <li>batch_number: ID in which batch the part was manufactured.</li> </ul>

Data for: Assortative mating in an ecological context: Effects of mate choice errors and relative species abundance on the frequency and asymmetry of hybridization

The frequency and asymmetry of mixed-species mating set the initial stage for the ecological and evolutionary implications of hybridization. How such patterns of mixed-species mating, in turn, are influenced by the combination of mate choice errors and relative species abundance remain largely unknown. We develop a mathematical model that generates predictions for how relative species abundances and mate choice errors affect hybridization patterns. When mate choice errors are small (<5%) the highest frequency of hybridization occurs when one of the hybridizing species is at low abundance, but when mate choice errors are high (>5%) the highest hybridization frequency occurs when species occur in equal proportions. Furthermore, females of the less abundant species are overrepresented in mixed-species matings. We compare our theoretical predictions with empirical data on naturally hybridizing Ficedula flycatchers and find that hybridization is highest when the two species occur in equal abundance, implying rather high mate choice errors. We discuss ecological and evolutionary implications of our findings and encourage future work on hybrid zone dynamics that take demographic aspects, such as relative species abundance, into account.

opencc-by-4.0Jun 2022View details →

PhytoNodes for Environmental Monitoring: Stimulus Classification based on Natural Plant Signals in an Interactive Energy-efficient Bio-hybrid System

Cities worldwide are growing, putting bigger populations at risk due to urban pollution. Environmental monitoring is essential and requires a major paradigm shift. We need green and inexpensive means of measuring at high sensor densities and with high user acceptance. We propose using phytosensing: using natural living plants as sensors. In plant experiments we gather electrophysiological data with sensor nodes. We expose the plant Zamioculcas zamiifolia to five different stimuli: wind, temperature, blue light, red light, or no stimulus. Using that data we train ten different types of artificial neural networks to classify measured time series according to the respective stimulus. We achieve good accuracy and succeed in running trained classifying artificial neural networks online on the microcontroller of our small energy-efficient sensor node. To indicate later possible use cases, we showcase the system by sending a notification to a smartphone application once our continuous signal analysis detects a given stimulus.   Data repository for our paper "PhytoNodes for Environmental Monitoring: Stimulus Classification based on Natural Plant Signals in an Interactive Energy-efficient Bio-hybrid System", submitted to the GoodIT conference. Please refer to the paper for more information.   Contents of this repository <ul> <li>mu_interface: Code for our data collection plant experiments, based on Raspberry Pis and the <a href="http://cybertronica.co/?q=products/phytosensor">Cybertronica phytosensing and phytoactuating system</a>.</li> <li>raw_data: The datasets from our plant experiments for the stimuli wind, temperature, red light, blue light, and no stimulus.</li> <li>dl-4-tsc: Deep learning framework developed by <a href="https://doi.org/10.1007/s10618-019-00619-1">Fawaz et. al (Deep learning for time series classification: a review)</a> and adapted to our use case. Find the training and testing datasets in the archives folder as well as the trained classifiers in the results folder.</li> <li>classification_results.ods: Overview of the results from the deep learning framework (accuracy, precision, recall, training time).</li> <li>TFLite_Models: The trained classifiers in TensorFlow Lite Format.</li> <li>00_AI_BLE_MeasuringOnlyWind: Source code for classification on STM-based PhytoNodes (using MCDCNN two-class classifier) and Bluetooth communication. The code is written for the STM32WB55 Nucleo board and can be transferred to the dongle.</li> <li>zavrsniProjekt_iOS: Source code of the iOS app used to receive data from the STM-based PhytoNodes.</li> <li>Watchplant_application_documentation.pdf: Instructions to build and use the iOS app.</li> </ul>

Data from: Hybrid incompatibility between D. virilis and D. lumei is stronger in the presence of transposable elements

Mismatches between parental genomes in selfish elements are frequently hypothesized to underlie hybrid dysfunction and drive speciation. However, because the genetic basis of most hybrid incompatibilities is unknown, testing the contribution of selfish elements to reproductive isolation is difficult. Here we evaluated the role of transposable elements (TEs) in hybrid incompatibilities between Drosophila virilis and D. lummei by experimentally comparing hybrid incompatibility in a cross where active TEs are present in D. virilis (TE+) and absent in D. lummei, to a cross where these TEs are absent from both D. virilis (TE-) and D. lummei genotypes. Using genomic data, we confirmed copy number differences in TEs between the D. virilis (TE+) strain and the D. virilis (TE-) strain and D. lummei. We observed F1 postzygotic reproductive isolation exclusively in the interspecific cross involving TE+ D. virilis but not in the cross involving TE- D. virilis. This precisely mirrors the intraspecies dysgenic phenotype where teste atrophy only occurs when TE+ D. virilis is the paternal parent. A series of backcross experiments, designed to account for alternative models of hybrid incompatibility, showed that both F1 hybrid incompatibility and intrastrain dysgenesis is consistent with the action of TEs rather than other, genic, interactions. A further Y-autosome interaction contributes to additional, sex-specific, inviability in one direction of this cross combination. These experiments demonstrate that TEs that cause intraspecies dysgenesis can increase reproductive isolation between closely related lineages, thereby adding to the processes that consolidate speciation.

Experimental test of selection against hybridization as a driver of avian signal divergence

Signal divergence may be pivotal in the generation and maintenance of new biodiversity by allowing closely related species to avoid some costs of co-occurrence. In birds, closely related, sympatric species are more divergent in their colour patterns than those that live apart, but the selective pressures driving this pattern remain unclear. Traditionally, signal divergence among sympatric species is thought to result from selection against hybridization, but broad evidence is lacking. Here, we conducted field experiments on naïve birds using spectrometer-matched, painted 3D-printed models to test whether selection against hybridization drives colour pattern divergence in the genus Poecile. To address selection for male colour pattern divergence without the influence of learning or the evolution of female discrimination in sympatry, we simulated secondary contact between Poecile species, and conducted mate choice experiments on naïve, allopatric females. We found that female black-capped chickadees (P. atricapillus) are equally likely to perform copulation solicitation displays to sympatric and allopatric heterospecific congeners when they are paired with conspecifics, but exhibit a strong preference for less divergent males when presented with paired heterospecific congeners. These results suggest that increased colour pattern divergence among sympatric species can reduce the likelihood of mixed mating in some contexts, and therefore should be favoured by selection against hybridization.

Data for: Range and niche expansion through multiple interspecific hybridization - a genotyping by sequencing analysis of Cherleria (Caryophyllaceae)

Background: Cherleria (Caryophyllaceae) is a circumboreal genus that also occurs in the high mountains of the northern hemisphere. In this study, we focus on a clade that diversified in the European High Mountains, which was identified using nuclear ribosomal (nrDNA) sequence data in a previous study. With the nrDNA data, all but one species was monophyletic, with little sequence variation within most species. Here, we use genotyping by sequencing (GBS) data to determine whether the nrDNA data showed the full picture of the evolution in the genomes of these species. Results: The overall relationships found with the GBS data were congruent with those from the nrDNA study. Most of the species were still monophyletic and many of the same subclades were recovered, including a clade of three narrow endemic species from Greece and a clade of largely calcifuge species. The GBS data provided additional resolution within the two species with the best sampling, C. langii and C. laricifolia, with structure that was congruent with geography. In addition, the GBS data showed significant hybridization between several species, including species whose ranges did not currently overlap. Conclusions: The hybridization led us to hypothesize that lineages came in contact on the Balkan Peninsula after they diverged, even when those lineages are no longer present on the Balkan Peninsula. Hybridization may also have helped lineages expand their niches to colonize new substrates and different areas. Not only do genome-wide data provide increased phylogenetic resolution of difficult nodes, they also give evidence for a more complex evolutionary history than what can be depicted by a simple, branching phylogeny.

opencc-by-4.0Jun 2022View details →

Broadband microwave detection using electron spins in a hybrid diamond-magnet sensor chip

Dataset accompanying "Broadband microwave detection using electron spins in a hybrid diamond-magnet sensor chip".

opencc-by-4.0Jul 2022View details →

Integration of an event-driven Timepix3 hybrid pixel detector into a cryo-EM workflow

Abstract The development of direct electron detectors has played a key role in low-dose electron microscopy imaging applications. Monolithic active-pixel sensor (MAPS) detectors are currently widely applied for cryogenic electron microscopy (cryo-EM); however, they have best performance at 300~kV, have relatively low read-out speed and only work in imaging mode. Hybrid pixel detectors (HPDs) can operate at any energy, have a higher DQE at lower voltage, have unprecedented high time resolution, and can operate in both imaging and diffraction modes. This could make them well-suited for novel low-dose life-science applications, such as cryo-ptychography, iDPC, and liquid cell imaging. Timepix3 is not frame-based, but truly event-based, and can record individual hits with 1.56~ns time resolution. Here, we present the integration of such a detector into a cryo-EM workflow and demonstrate that it can be used for automated data collection on biological specimens. The performance of the detector in terms of MTF and DQE has been investigated at 200~kV and we studied the effect of deterministic blur. We describe a single-particle analysis structure of \SI{3}{\angstrom} resolution and compare it with Falcon3 data collected under the same microscope. These studies could pave the way toward more efficient low-dose single-particle techniques. Data description Data has been split up in several different directories. In general: each directory contains individual READMEs Flat fields Collected on both TImepix3 and Falcon3 at 200 kV using a Tecnai Arctica microscope. These data have been used for calculating NPS, ToT correction and gain correction.  Knife edge Collected on both TImepix3 and Falcon3 at 200 kV using a Tecnai Arctica microscope. These data have been used for calculating MTF. ToT correction calibration file This calibration file has been used to correct all raw Timepix3 data. Including micrographs deposited in EMPIAR. Gain correction Gain correction files calculated from flat field data for several different image formation methods of the Timepix3. The Python script for calculating the gain has been included. Software The software tpx3HitParser, tpx3EventViewer and the MTF-NPS-DQE scripts have listed as related identifiers to this entry.

opencc-zeroJul 2022View details →

Evidence of hybrid breakdown among invasive hybrid cattails (Typha x glauca)

Interspecific hybridization has varied consequences for offspring fitness, with implications for the maintenance of species integrity. Hybrid vigour, when it occurs, can peak in first-generation (F1) hybrids and then decline in advanced-generation (F2+) hybrids. This hybrid breakdown, together with the processes affecting patterns of hybridization and hybrid fitness, determine the evolutionary stability of hybrid zones. An extensive hybrid zone in North America involving the cattails Typha latifolia, T. angustifolia, and their invasive hybrid T. × glauca is characterized by hybrid vigour among F1s, but the fitness of advanced-generation hybrids has not been studied. We compared seed germination and plant growth of T. latifolia (parental L), F1 T. × glauca (F1), hybrid backcrosses to T. angustifolia (bcA) and T. latifolia (bcL), and advanced-generation (F2) hybrids. Consistent with expectations under hybrid breakdown, we found reduced plant growth for F2 hybrids in comparison with F1s (plant height and above-ground biomass) and parental Ls (above-ground biomass). Backcrossed hybrids had intermediate measures of plant growth and bcLs were characterized by reduced seed germination in comparison with parental Ls. Hybrid breakdown could make the formation of F1s in North America finite because (1) hybridization among cattails is asymmetric, with T. angustifolia but not T. latifolia subject to genetic swamping, and (2) T. angustifolia is less common and subject to competitive displacement by F1s. Hybrid breakdown is therefore expected to reduce hybrid frequencies over time, contributing to the long-term maintenance of T. latifolia – the only native cattail in the study region.

opencc-by-4.0Jul 2022View details →

Molecular evidence for introgressive hybridization in New Zealand masked gulls

Genetic data and codes to reproduce the analyses from the manuscript : Given, A. D., Mills, J. A., Momigliano, P., & Baker, A. J. (2022). Molecular evidence for introgressive hybridization in New Zealand masked gulls. Ibis. https://doi.org/10.1111/ibi.13117 The data and codes are  in  two zipped folders <ol> <li>FSC.zip</li> <li>PopGen.zip</li> </ol> The FSC.zip folder contains data and scripts to reproduce the fastsimcoal simulations and to calculate summary statistics from observed and simulated data. It also includes the results from these analyses and an R script to run ABC model selection via random forest.   The PopGen.zip folder contains the microsatellite dataset in both genepop (RB-BB.gen) and structure (RB-BB.str) formats , the results from STRUCTURE analyses (folder RB-BB_STRUCT), and an R script (Popgen_analyses.r) to reproduce population genetic analyses (PCA and summary statistics: FST, and estimate HWE,  HO and HE) and plots.

opencc-zeroAug 2022View details →

Ecological outcomes of hybridization vary extensively in Catostomus fishes

Hybridization outcomes vary geographically and can depend on the environment. Hybridization can also reshape biotic interactions, leading to ecological shifts. If hybrids function differently ecologically in ways that enhance or reduce fitness, and those ecological roles vary geographically, ecological factors might explain variation in hybridization outcomes. However, relatively few studies have focused on ecological traits of hybrids. We compared the feeding ecology of Catostomus fish species and hybrids by using stable isotopes δ13C and δ15N as a proxy for diet and habitat use, and compared two native species, an introduced species, and three interspecific hybrid crosses. We included hybrids and parental species from seven rivers where hybridization outcomes vary. Relative isotopic niches of native species varied geographically, but native species did not fully overlap in isotopic space in any river sampled, suggesting little overlap of resource use between historically sympatric species. The introduced species overlapped with one or both native species in every river, suggesting similar resource use and potential competition. Hybrids occupied intermediate, matching, or more transgressive isotopic niches, and varied within and among rivers. Ecological outcomes of hybridization varied across locations, implying that hybridization might have unpredictable, idiosyncratic ecological effects. --

opencc-zeroAug 2022View details →

On the impermanence of species: The collapse of genetic incompatibilities in hybridizing populations

Species pairs often become genetically incompatible during divergence, which is an important source of reproductive isolation. An idealized picture is often painted where incompatibility alleles accumulate and fix between diverging species. However, recent studies have shown both that incompatibilities can collapse with ongoing hybridization, and that incompatibility loci can be polymorphic within species. This paper suggests some general rules for the behavior of incompatibilities under hybridization. In particular, we argue that redundancy of genetic pathways can strongly affect the dynamics of intrinsic incompatibilities. Since fitness in genetically redundant systems is unaffected by introducing a few foreign alleles, higher redundancy decreases the stability of incompatibilities during hybridization, but also increases tolerance of incompatibility polymorphism within species. We use simulations and theories to show that this principle leads to two types of collapse: in redundant systems, exemplified by classical Dobzhansky-Muller incompatibilities, collapse is continuous and approaches a quasi-neutral polymorphism between broadly sympatric species, often as a result of isolation-by-distance. In non-redundant systems, exemplified by coevolution among genetic elements, incompatibilities are often stable, but can collapse abruptly with spatial traveling waves. As both types are common, the proposed principle may be useful in understanding the abundance of genetic incompatibilities in natural populations.

opencc-zeroAug 2022View details →

Biomimetic robotic skin implemented with hydrogel-elastomer hybrids and tomographic imaging methods

Human skin perceives physical stimuli applied to the body and mitigates the risk of physical interaction through its soft and resilient mechanical properties. Social robots would benefit from whole-body robotic skin (or tactile sensors) resembling human skin in realizing a safe, intuitive, and contact-rich interaction with humans. However, existing soft tactile sensors show several drawbacks (complex structure, poor scalability, and fragility), which limit their application in whole-body robotic skin. Here, we introduce biomimetic robotic skin based on hydrogel-elastomer hybrids and tomographic imaging. The developed skin consists of tough hydrogel and silicone elastomer forming a skin-inspired multilayer structure, achieving sufficient softness and resilience for protection. The sensor structure can also be easily repaired with adhesives even after severe damage (incision). For multimodal tactile sensation, electrodes and microphones are deployed in the sensor structure to measure local resistance changes and vibration due to touch. The ionic hydrogel layer is deformed due to an external force, and the resulting local conductivity changes are measured via electrodes. The microphones also detect the vibration generated from touch to determine the location and type of dynamic tactile stimuli. The measurement data are then converted into multimodal tactile information through tomographic imaging and deep neural networks. We further implement a sensorized cosmetic prosthesis, demonstrating that our design could be used to implement deformable or complex-shaped robotic skin.

opencc-by-4.0Mar 2022View details →

Preserving and sharing born-digital and hybrid objects from and across the National Collection (Decision-Making Model)

When considering the complex challenges faced by cultural heritage organisations in collecting, preserving and sharing born digital and hybrid objects, it becomes clear that the process of defining solutions as a community of practice is in its early probing phase: characterised as tentative, exploratory, questioning, experimental. The workshops within this Preserving and sharing born-digital and hybrid objects from and across the National Collection project, which examined the case studies from multiple angles, yielded a richly discursive examination of the main considerations. This Decision Model represents an attempt to create a structured representation of those main considerations and the discourse from the workshops, to codify the main decision-making processes that an organisation may go through when assessing an acquisition of such an object, categorised into high level areas. It attempts to create a traversable system that could be used by collections professionals in their work - policy makers, managers, collections management or digital preservation practitioners, conservators.

opencc-by-4.0Jan 2022View details →

Preserving and sharing born-digital and hybrid objects from and across the National Collection (January 2022)

This report is one of a set of outputs from the Arts and Humanities Research Council funded project ‘Preserving and sharing born-digital and hybrid objects from and across the National Collection’. It has been designed to provide an extensive account of the project research activities and findings, to be useful to museum, heritage, and preservation professionals, as well as to scholars interested in born-digital materials.