cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.13020/d62q21
title: Constrained Buckling of Variable Length Elastica: Solution by Geometrical Segmentation

description: The associated paper to this dataset proposes a method to analyze the post-buckling response of a planar elastica subjected to unilateral constraints. The method rests on assuming a deformed shape of the elastica that is consistent with an assumed buckling mode and given unilateral constraints, and on uniquely segmenting the elastica so that each segment is a particular realization of the same canonical problem. An asymptotic solution of the canonical problem, which is characterized by clamped-pinned boundary conditions and monotonically varying curvature, is derived using a perturbation technique. The complete solution of the constrained elastica is constructed by assembling the solution for each segment. It entails solving a nonlinear system of algebraic equations that embodies the continuity conditions between the segments and the contact constraints.

The method is then applied to analyze the post-buckling response of a planar weightless elastica compressed inside two rigid frictionless horizontal walls. The length of the elastica could be either constant, or variable, but the focus of the analysis is on the response of a variable length elastica, which is gradually inserted inside the conduit. In the insertion problem, a configurational force is generated at the insertion point, which is not present in the classical problem of a constant length elastica (Bigoni et al, in Mechanics of Materials, 2015)[10].

The proposed approach is shown to lead to a simple and accurate numerical technique to simulate the constrained buckling of an elastica. The optimal sequence of equilibrium configurations of the elastica associated with a monotonic force- or displacement-control loading is deduced in accordance with the principle of minimum energy.
description: The MATLAB codes demonstrate the example of a free-standing fold described in Section 4.3 of the related paper (under review). In particular, the MATLAB code "Example_Secondary" provides the solution for a pinned-pinned elastica of constant length, characterized by two symmetric discrete contacts between the elastica and the upper wall and a free standing fold. 

The MATLAB code, "fbnd_secondary," solves a system of equations for this example, using the nonlinear least-squares MatLab solver "lsqnonlin." With this solver, convergence of the solution is achieved even with a poor initial guess.

The supplementary paper provides an analytical derivation of the buckling response of a constrained elastica clamped at both ends, as opposed to the response of pinned-pinned elastica analyzed in the paper.
DOI: 10.13020/c37f-nv41
title:  TnSeq of Himar1 transposon library of Mycobacterium tuberculosis H37Rv grown in vitro (on Mtb YM rich or Mtb minimal).
DOI: 10.13020/d61013
title: Indoor Spatial Updating with Reduced Visual Information

description: Spatial updating refers to the ability to keep track of position and orientation while moving through an environment. People with impaired vision may be less accurate in spatial updating with adverse consequences for indoor navigation. In this study, we asked how artificial restrictions on visual acuity and field size affect spatial updating, and also judgments of the size of rooms. Normally sighted young adults were tested with artificial restriction of acuity in Mild Blur (Snellen 20/135) and Severe Blur (Snellen 20/900 ) conditions, and a Narrow Field (8º) condition. The subjects estimated the dimensions of seven rectangular rooms with and without these visual restrictions. They were also guided along three-segment paths in each of the rooms. At the end of each path, they were asked to estimate the distance and direction to the starting location. In Experiment 1, the subjects walked along the path. In Experiment 2, they were pushed in a wheelchair to determine if reduced proprioceptive input would result in poorer spatial updating. With unrestricted vision, mean Weber fractions for room-size estimates were near 20%. Severe Blur but not Mild Blur yielded larger errors in room-size judgments. The Narrow Field was associated with increased error, but less than with Severe Blur. There was no effect of visual restriction on estimates of distance back to the starting location, and only Severe Blur yielded larger errors in the direction estimates. Contrary to expectation, the wheelchair subjects did not exhibit poorer updating performance than the walking subjects, nor did they show greater dependence on visual condition. If our results generalize to people with low vision, severe deficits in acuity or field will adversely affect the ability to judge the size of indoor spaces, but updating of position and orientation may be less affected by visual impairment.
description: The data are contained in a csv spreadsheet. There is an accompanying txt file that explains the columns in the spreadsheet. Please see the referenced article for more information about the methods.
DOI: 10.13020/d6q08z
title: MNREAD Baseline Data for Normal Vision Across the Lifespan

description: The continuous-text reading-acuity test MNREAD is designed to measure the reading performance of people with normal and low vision. This test is used to estimate maximum reading speed (MRS), critical print size (CPS), reading acuity (RA), and the reading accessibility index (ACC). 

The present data contains MNREAD data from 645 normally sighted participants ranging in age from 8 to 81 years. The data were collected in several studies conducted by different testers and at different sites in our research program, enabling evaluation of robustness of the test.

The data allows to: 1) study the age dependence of reading performance for normally sighted individuals; 2) provide baseline data for MNREAD testing.
description: Contains MNREAD estimates for 654 participants with normal vision (age range 8-81). The four MNREAD estimates are : Maximum Reading Speed, Reading Accessibility Index, Critical Print Size, Reading Acuity.
DOI: 10.13020/d6qk5p
title: Thermal Processing of Diblock Copolymer Melts Mimics Metallurgy

description: Small-angle x-ray scattering experiments conducted with compositionally asymmetric low
molar mass poly(isoprene)-b-poly(lactide) diblock copolymers reveal an extraordinary
thermal history dependence. The development of distinct periodic crystalline or aperiodic
quasicrystalline states depends on how specimens are cooled from the disordered state to
temperatures below the order-disorder transition temperature. Whereas direct cooling
leads to the formation of documented morphologies, rapidly quenched samples that
are then heated from low temperature form the hexagonal C14 and cubic C15 Laves phases
commonly found in metal alloys. Self-consistent mean-field theory calculations show
that these, and other associated Frank-Kasper phases, have nearly degenerate free
energies, suggesting that processing history drives the material into long-lived metastable
states defined by self-assembled particles with discrete populations of volumes and
polyhedral shapes.
description: The data provided here contains the results of self-consistent field theory (SCFT) calculations. Specifically, the folder contains the input and output files for all the SCFT calculations that are shown in Fig. 1 of the main manuscript and Figs. S2-S7 of the supplemental materials. Using these files and the open source PSCF software available at pscf.cems.umn.edu, one can reproduce all the SCFT results presented in the main manuscript and its supplemental materials.
DOI: 10.13020/d6v599
title: Supporting Data for “Renewable, Degradable, and Chemically Recyclable Cross-Linked Elastomers”

description: These files contain data along with associated output from instrumentation supporting all results reported in Jacob P. Brutman, Guilhem X. De Hoe, Deborah K. Schneiderman, Truyen N. Le, and Marc A. Hilmyer Renewable, Degradable, and Chemically Recyclable Cross-Linked Elastomers. Industrial & Engineering Chemistry Research 2016 55 (42), 11097-11106. In Brutman et. al. we found: Most commercial elastomers, typified by vulcanized natural rubber, are cross-linked polymers and as such cannot easily be reprocessed or recycled. While some are derived from renewable resources, the majority are produced from petroleum feedstocks and do not easily degrade. In this study, renewable elastomers based on β-methyl-δ-valerolactone were produced using two different methodologies: (1) tandem copolymerization/cross-linking with a bis(six-membered cyclic carbonate); (2) cross-linking of a linear poly(β-methyl-δ-valerolactone) homopolymer with a free-radical generator. The mechanical properties of these materials were investigated; tensile strengths of up to 12 MPa and elongations of up to 2000% were observed. Inclusion of a filler (fumed silica) was used to enhance the performance of the elastomers without significant loss of elasticity, with some composites exhibiting tensile strengths nearly double that of the neat elastomer. Aqueous degradation studies indicated that the materials were capable of degradation in acidic and basic conditions at 60 °C. Moreover, these cross-linked elastomers can also be chemically recycled, yielding monomer in high purity and yield (>91% and 93%, respectively).
description: Full description of the data is in the attached Readme file.
DOI: 10.13020/s6s5-2d61
title: Continuous Forest Inventory Plots for the UMN Cloquet Forestry Center

description: The University of Minnesota Cloquet Forestry Center is a field research and instructional station associated with the College of Food, Agricultural, and Natural Resources Sciences (CFANS). Continuous Forest Inventory data has been collected for the CFC since 1959. The network of permanent forest measurement plots consists of 406 1/7 acre plots with a subset of these plots re-measured up to seven times since establishment. The last re-measurement occurred Summer 2014. The majority of the CFI plots were geolocated with a Trimble GeoXT GNSS receiver in 2014 or 2015 to obtain sub-meter precision for each plot center. Plot locations are marked in the field with a tagged center post with painted tree numbers oriented to plot center. Eight plots without precision GNSS locations are indicated within the attribute table. One plot location is missing from this dataset as it could not be relocated in the field (Plot_ID = '620'). The most recent report on the UMN Cloquet Forestry Center CFI is available as 2016 Staff Paper No. 243 published through the UMN Department of Forest Resources and summarizes findings from the 2014 remeasurement. The associated 1959-2014 data are available through the Digital Repository of the University of Minnesota (DRUM) at: https://doi.org/10.13020/096z-kg59.
description: The University of Minnesota Cloquet Forestry Center is a field research and instructional station associated with the College of Food, Agricultural, and Natural Resources Sciences (CFANS). Continuous Forest Inventory data has been collected for the CFC since 1959. The network of permanent forest measurement plots consists of 406 1/7 acre plots with a subset of these plots re-measured up to seven times since establishment. The last re-measurement occurred Summer 2014. The majority of the CFI plots were geolocated with a Trimble GeoXT GNSS receiver in 2014 or 2015 to obtain sub-meter precision for each plot center. Plot locations are marked in the field with a tagged center post with painted tree numbers oriented to plot center. Eight plots without precision GNSS locations are indicated within the attribute table. One plot location is missing from this dataset as it could not be relocated in the field (Plot_ID = '620'). The most recent report on the UMN Cloquet Forestry Center CFI is available as 2016 Staff Paper No. 243 published through the UMN Department of Forest Resources and summarizes findings from the 2014 remeasurement.
description: The University of Minnesota Cloquet Forestry Center (CFC) Continous Forest Inventory (CFI) plot network shows mapped locations of CFI plots established between 1959 and 2014 for use in ongoing forest inventory and analysis efforts at the CFC.
DOI: 10.13020/4h9x-xq26
title: Validating a Model of Architectural Hazard Visibility with Low-Vision Observers

description: Pedestrians with low vision are at risk of injury when hazards, such as steps and posts, have low visibility. This study aims at validating the software implementation of a computational model that estimates hazard visibility.  The model takes as input a photorealistic 3-D rendering of an architectural space, and the acuity and contrast sensitivity of a low-vision observer, and outputs estimates of the visibility of hazards in the space.  Our experiments explored whether the model can predict the likelihood of observers correctly identifying hazards. 
We tested fourteen normally sighted subjects with blur goggles that reduced acuity to 1.2 logMAR or 1.6 logMAR and ten low-vision subjects with acuities ranging from 0.8 logMAR to 1.6 logMAR. Subjects viewed computer-generated images of a walkway containing five possible targets ahead—large step up, large step-down, small step up, small step down, or a flat continuation. Each subject saw these stimuli with variations of lighting and viewpoint in 250 trials and indicated which of the five targets was present. The model generated a score on each trial that estimated the visibility of the target. If the model is valid, the scores should be predictive of how accurately the subjects identified the targets. We used logistic regression to examine the correlation between the scores and the participants’ responses. 
For twelve of the fourteen normally sighted subjects with artificial acuity reduction and all ten low-vision subjects, there was a significant relationship between the scores and the participant’s probability of correct identification. 
These experiments provide evidence for the validity of a computational model that predicts the visibility of architectural hazards. The software implementation of the model may be useful for architects to assess the visibility of hazards in their designs, thereby enhancing the accessibility of spaces for people with low vision.
description: The three text files "UoMRLVsubjScore", "UoMSLVSubjScore", and "UoMLVSubjScoreROI_Central" contain the Hazard Visibility Scores (HVS) generated by the DeVAS software for each trial based on the stimulus image and the subject's visual acuity (VA) and contrast sensitivity (CS). The first two text files used comprehensive ROI, while the third file used central ROI. "UoMRLVsubjScore" and "UoMLVSubjScoreROI_Central" were based on the low-vision subjects' vision conditions, and the "UoMSLVSubjScore" were based on the normal-sighted subjects. The software is available online via https://github.com/visual-accessibility/DeVAS-filter. 
The four CSV files, "SLVCSV_UoM_Mod", "SLVCSV_UoM_Sev", "RLVCSV_UoM", and "RLVCSV_ROI_Central" are the file used for logistic regression. "SLVCSV_UoM_Mod" contains the data from normally-sighted subjects wearing moderate blur goggles, and "SLVCSV_UoM_Sev" contains the data from normally-sighted subjects wearing severe blur goggle. "RLVCSV_UoM" contains the data from low-vision subjects.  See the readme.txt file for more information.
DOI: 10.13020/d6rx0j
title: Experimental data on pore moduli of porous rock

description: These data address two key questions: (i) is Ks'' a constant and (ii) under what conditions does Ks'' = Ks hold. We present unique laboratory experiments that enable the direct measurement of Ks'', for the first time, for ideal and natural porous solids.
description: Deposited here are Excel spreadsheets containing all figure data except for figures 1 and 2. Descriptions of each file can be found in "Tarokh-Labuz-Readme.txt".
DOI: 10.13020/5r00-8c56
title: Snapshot Safari Educational Materials

description: Snapshot Safari (www.snapshotsafari.org) is a cross-continental network of biodiversity monitoring programs run by the University of Minnesota Lion Center (www.lioncenter.umn.edu/snapshot-safari). To address the urgent need for accurately assessing vulnerable wildlife populations, we deployed over two dozen camera trap surveys distributed in protected areas across Africa. We rely on the help of online volunteers ("citizen scientists") to help classify animals captured in our millions of camera trap images. The citizen science platform provides a novel opportunity for public engagement and science education, and we have created educational multimedia based on the Snapshot Safari citizen science experience to promote these learning opportunities. Here, we present activities and videos aimed at a middle school-level audience that use our camera trap images to teach ecological and conservation principles.
description: These materials were created by Jessica Dewey as part of a Ph.D. program at University of Minnesota. This collection contains six educational activities to teach ecological principles via authentic learning experiences using read data from our wildlife surveys. Activity 1 guides students through setting up a Zooniverse account and take part in citizen science projects. Activity 2 helps students formulate ecological questions base on camera trap image data. Activity 3 teaches students about the different daily activity patterns of African species. Activity 4 presents students with data from a predator playback experiment and asks students to formulate hypotheses about predator-prey interactions. Activity 5 guides students through the process of connecting to the Zooniverse mobile app. Activity 6 presents an interactive timeline of conservation activities at the Snapshot Safari sites used in these programs. As a note: camera trap data is delivered to the UMN Lion Center several times a year. If a project you are interested in does not have data at the moment, check back soon! Classified images can still be accessed by clicking the "Classify" tab within individual projects.
DOI: 10.13020/ner9-eb82
title: High Frequency Oxygen Data from Eight Shallow Prairie Pothole Lakes, 2009-2013

description: Dissolved oxygen controls important processes in lakes, from chemical reactions to organism community structure and metabolism. In shallow lakes, small volumes allow for large fluctuations in dissolved oxygen concentrations, and the oxygen regime can greatly affect ecosystem-scale processes. This data includes high frequency dissolved oxygen measurements that we used to examine differences in oxygen regimes between two alternative stable states that occur in shallow lakes. We compared annual oxygen regimes in four macrophyte-dominated, clear state lakes to four phytoplankton-dominated, turbid state lakes by quantifying oxygen concentrations, anoxia frequency, and measures of whole-lake metabolism. Oxygen regimes were not significantly different between lake states throughout the year except for during the winter under-ice period. During winter, clear lakes had less oxygen, higher frequency of anoxic periods, and higher oxygen depletion rates. Oxygen depletion rates correlated positively with peak summer macrophyte biomass. Due to lower levels of oxygen, clear shallow lakes may experience anoxia more often and for longer duration during the winter, increasing the likelihood of experiencing fish winterkill. These observations have important implications for shallow lake management, which typically focuses efforts on maintaining the clearwater state.
description: This dataset includes high frequency oxygen measurements from 8 shallow lakes. Each lake has a separate data file of oxygen measurements from the study period. Also included are data files of water chemistry, macrophyte biomass, and calculated metabolism values which include all lakes.
DOI: 10.13020/9td6-c784
title:  Giant sulfur bacteria (Beggiatoaceae) from sediments below the Benguela Upwelling System the host diverse microbiomes 

description: Due to their lithotrophic metabolisms, morphological complexity and conspicuous appearance, members of the Beggiatoaceae have been extensively studied for more than 100 years. These bacteria are known to be primarily sulfur-oxidizing autotrophs that commonly occur in dense mats at redox interfaces. Their large size and the presence of a mucous sheath allows these cells to serve as sites of attachment for communities of other microorganisms. But little is known about their individual niche preferences and attached microbiomes, particularly in marine environments, due to a paucity of cultivars and their prevalence in habitats that are difficult to access and study. Therefore, in this study, we compare Beggiatoaceae strain composition, community composition, and geochemical profiles collected from sulfidic sediments at four marine stations off the coast of Namibia. To elucidate community members that were directly attached and enriched in both filamentous Beggiatoaceae, namely Ca. Marithioploca spp. and Ca. Maribeggiatoa spp., and non-filamentous Beggiatoaceae, Ca. Thiomargarita spp., the two morphotypes were rinsed of sediment debris and pooled by morphotype for iTag sequencing. The Beggiatoaceae samples collected from a highly sulfidic site were enriched in strains of sulfur-oxidizing Campylobacterota, who may promote a more hospitable setting for the Beggiatoaceae who are known to have a lower tolerance for sulfide to oxygen ratios. Otherwise, specific Beggiatoaceae niche preferences were not elucidated by the methods employed in this study. We found just a few host-specific associations with the motile filamentous morphotypes.  On the contrary, we detected 123 host specific enrichments with non-motile chain forming Beggiatoaceae. Potential metabolisms of the enriched strains include fermentation of host sheath, syntrophic exchange of H2 and acetate, inorganic sulfur metabolism, and nitrite oxidation. Surprisingly, we did not detect any enrichments of anaerobic ammonium oxidizing bacteria as previously suggested and postulate that less well-studied anaerobic ammonium oxidation pathways may be occurring instead.
DOI: 10.13020/d6hc-bw36
title: Data and R code to support: Estimating densities of zebra mussels (Dreissena polymorpha) in early invasions using distance sampling

description: These files are the data and code needed to reproduce the analysis of the manuscript "Estimating densities of zebra mussels (Dreissena polymorpha) in early invasions using distance sampling". The data include spatial coordinates of transects used to survey for zebra mussels in Lake Sylvia and Lake Burgan in the summer of 2017, the counts of zebra mussels on each transect, and environmental covariates collected along transects and at each detection. We also provide the R code needed to process and analyze these data following the distance survey approach described in the manuscript. We provide code for a straightforward distance survey, which doesn't include any spatial covariate information, as well as a more computationally intensive analysis that does include spatial covariates.
description: These files are the data and code needed to reproduce the analysis of the manuscript "Estimating densities of zebra mussels (Dreissena polymorpha) in early invasions using distance sampling". The data include spatial coordinates of transects used to survey for zebra mussels in Lake Sylvia and Lake Burgan in the summer of 2017, the counts of zebra mussels on each transect, and environmental covariates collected along transects and at each detection.  We also provide the R code needed to process and analyze these data following the distance survey approach described in the manuscript. We provide code for a straightforward distance survey, which doesn't include any spatial covariate information, as well as a  more computationally intensive analysis that does include spatial covariates.
DOI: 10.13020/d6qx07
title: Silver: an Attribute Grammar System

description: Silver is an attribute grammar system which supports higher-order, reference, and collection attributes.  It also supports forwarding and provides a modular well-definedness analysis to ensure composability of language extensions. There may be newer, unarchived versions of this software at http://melt.cs.umn.edu.