Johns Hopkins Research Data Repository
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Current-voltage, voltage-temperature, cyclic voltammetry, morphological, and spectroscopic raw data
No full textThis dataset is backup information for the publication whose abstract is reproduced here. Air stable and soluble tetrabutylammonium fluoride (TBAF), is demonstrated as an efficient n-type dopant for the conjugated polymer ClBDPPV. Electron transfer from F− anions to the π-electron deficient polymer ClBDPPV through anion-π electronic interactions is strongly corroborated by the combined the results of electron spin resonance (ESR), UV-Vis-NIR and ultraviolet photoelectron spectroscopy (UPS). Doping of ClBDPPV with 25 mol% TBAF boosts electrical conductivity to up to 0.62 S cm-1, among the highest conductivities that has been reported for solution processed n-type conjugated polymers, with a thermoelectric power factor of 0.63 μW m−1 K−2 in air. Importantly, the Seebeck coefficient agrees with recently published correlations to conductivity. Moreover, the F- doped ClBDPPV shows significant air stability, maintaining the conductivity of over 0.1 S cm-1 in a thick film after exposure to air for one week, to the best of our knowledge the first report of an air stable solution processable n-doped conductive polymer with this level of conductivity. The result shows that using solution processable small-anion salts such as TBAF as a n-dopant of organic conjugated polymers possessing lower LUMO (< -4.2 eV) can open new opportunities toward high performance air stable solution processable n-type thermoelectric conjugated polymers
Data and code associated with the publication “Sensitivity of catchment transit times to rainfall variability under present and future climates”
No full textThis data and code were used to generate the figures in the publication “Sensitivity of catchment transit times to rainfall variability under present and future climates”
Current-voltage raw data, molecular weight and morphology measurement data, and spectra for thiophene polymer characterization and thermoelectric measurements
No full textThis dataset is backup information for the publication whose abstract is reproduced here. Four p-type polymers were synthesized by modifying poly(bisdodecylquaterthiophene) (PQT12) to increase oxidizability by p-dopants. A sulfur atom is inserted between the thiophene rings and dodecyl chains, and/or 3,4-ethylenedioxy groups are appended to thiophene rings of PQT12. Doped with NOBF4, PQTS12 (with sulfur in side chains) shows conductivity of 350 S cm-1, the highest reported nonionic conductivity among films made from dopant-polymer solutions. Doped with tetrafluorotetracyanoquinodimethane (F4TCNQ), PDTDE12 (with 3,4-ethylenedioxy groups on thiophene rings) shows conductivity of 140 S cm-1. The converse combinations of polymer and dopant, and formulations using a polymer with both the sulfur and ethylenedioxy modifications showed lower conductivities. The conductivities are stable in air without extrinsic ion contributions associated with PEDOT:PSS and that cannot support sustained current or thermoelectric voltage. Efficient charge transfer, tighter π-π stacking and strong intermolecular coupling are responsible for the conductivity. Values of nontransient Seebeck coefficient and conductivity agree with empirical modeling for materials with these levels of pure hole conductivity; the power factor compares favorably with prior p-type polymers made by the alternative process of immersion of polymer films into dopant solutions. Models and conductivities point to significant mobility increases induced by dopants, on the order of 1-5 cm2 V-1 s-1, supported by field-effect transistor studies of slightly doped samples. The thermal conductivities were in the range of 0.2 ~ 0.5 W m-1 K-1, typical for conductive polymers. The results point to further enhancements that could be obtained by increasing doped polymer mobilities
Data associated with the PlosONE publication “Implicit measures of receptive vocabulary knowledge in individuals with severe autism”
No full textImplicit measures of cognition are essential for assessing knowledge in individuals with severe autism because such individuals are often unable to make reliable overt behavioral responses. Here we test whether three implicit measures – eye movement monitoring (EM), pupillary dilation (PD), and event-related potentials (ERPs) – can reliably estimate vocabulary knowledge in individuals with severe autism. Five adults with severe autism were tested in a repeated-measures design with two tasks. High-frequency ‘known’ words (e.g. bus, airplane) and low-frequency ‘unknown’ words (e.g. ackee, cherimoya) were presented in a visual-world task (during which EM and PD data were collected) and a picture-word congruity task (during which ERP data were collected). Using a case study approach with single-subject analyses, we demonstrate that these implicit measures can provide estimates of receptive vocabulary knowledge in the majority of these participants. However, participants differed with respect to which measures were the most sensitive and which variables best predicted vocabulary knowledge. These implicit measures may be useful to assess language abilities in individuals with severe autism, but their use should be tailored to each individual
Data associated with publication "Wind farms providing secondary frequency regulation: Evaluating the performance of model-based receding horizon control"
No full textWe investigate the capability of wind farm to track a power reference signal to help ensure reliable power grid operations. The wind farm controller is based on a simple dynamic wind farm model and tested using high-fidelity simulations. We find that the dynamic nature of the wind farm model is vital for tracking the power signal, and the controlled wind farm would pass industry performance tests in most cases.
Simulation data output in the form of comma separated value files
Current-voltage raw data for transistors and micrograph morphology images for films
No full textThis dataset is backup information for the publication whose abstract is reproduced here. Layer-by-layer deposited guanine and pentacene in organic field-effect transistors (OFETs) is introduced. Through adjusting the layer thickness ratio of guanine and pentacene, the tradeoff of two electronic parameters in OFETs, charge carrier mobility and current on/off ratio, was controlled. The charge mobility was enhanced by depositing the pentacene over and between guanine layers and by increasing the proportion of pentacene in the layer-by-layer system, while the current on/off ratio was increased via the decreased off current induced by the guanine layers. The tunable device performance was mainly ascribed to the trap and dopant neutralizing properties of the guanine layers, which would decrease the density of free hydroxyl groups in the OFETs. Furthermore, the cost of the devices could be reduced remarkably via the adoption of the low-cost guanine
Data associated with the PLoS ONE publication 'A Brief Intervention for Preparing ICU Families to be Proxies: A Phase I Study' by Turnbull et al. 2017
No full textBackground: Family members of critically ill patients report high levels of conflict with clinicians, have poor understanding of prognosis, struggle to make decisions, and experience substantial symptoms of anxiety, depression, and post-traumatic stress regardless of patient survival status. Efficient interventions are needed to prepare these families to act as patient proxies.
Objectives: To assess a brief “patient activation” intervention designed to set expectations and prepare families of adult intensive care unit (ICU) patients to communicate effectively with the clinical team.
Design: Phase I study of acceptability and immediate side effects
Setting and Participants: 122 healthcare proxies of 111 consecutive patients with a stay of ≥24 hours in the Johns Hopkins Hospital Medical ICU (MICU), in Baltimore, Maryland.
Intervention: Reading aloud to proxies from a booklet (Flesch-Kincard reading grade level 3.8) designed with multidisciplinary input including from former MICU proxie
Data associated with the PLoS ONE publication 'Evaluation of a strategy for enrolling the families of critically ill patients in research using limited human resources' by Turnbull et al. 2017
No full textWe want to know if patient activation interventions can be adapted to help the friends and family members who choose to speak for incapacitated ICU patients. These friends and family members are called proxies. As a first step in this process, we conducted a Phase I study in the Medical Intensive Care Unit at Johns Hopkins Hospital, in Baltimore, Maryland. More information about this project can be accessed at www.piperscience.org/proxy-activation .
This dataset includes data and codebook for the study associated with the cited PLOS one publication. Certain variables in the public access version of the data were broadened and variables detailing patient and proxy relationships are not included to reduce identity disclosure risk. These may be obtained by direct request with approval by investigators local IRBs.
Rationale: Clinical trials of interventions aimed at the families of intensive care unit (ICU) patients have proliferated but recruitment for these trials can be challenging.
Objectives: To evaluate a strategy for recruiting families of patients currently being treated in an ICU using limited human resources and time-varying daily screening over 7 consecutive days
Methods: We screened the Johns Hopkins Hospital medical ICU census 7 days per week to identify eligible family members. We then made daily, in-person attempts to enroll eligible families during a time-varying 2-hour enrollment period until families declined participation, consented, or were no longer eligible
Data and code for the report: Ferguson, Gray, and Davis: an analysis of recorded crime incidents and arrests in Baltimore City, March 2010 through December 2015"
No full textThis collection includes: (1) the report and its appendices, (2) raw data files from the Baltimore Police Department downloaded from the Open Baltimore portal on February 3, 2016, and (3) an R project with associated analysis code that reproduces the key results of the report included herein: Morgan, Stephen L. and Joel A. Pally. "Ferguson, Gray, and Davis: An Analysis of Recorded Crime Incidents and Arrests in Baltimore City, March 2010 through December 2015." A Report Prepared for the 21st Century Cities Initiative at Johns Hopkins University. Baltimore, MD: Johns Hopkins University, 2016
Data associated with publication: Action enhances acoustic cues for 3-D target localization by echolocating bats.
No full textUnder natural conditions, animals encounter a barrage of sensory information, from which they must select
and interpret biologically relevant signals. Active sensing can facilitate this process by engaging motor systems in the sampling of sensory information. The echolocating bat serves as an excellent model to investigate the coupling between action and sensing, because it adaptively controls both the acoustic signals used to probe the environment, and movements to receive echoes at the auditory periphery. We report here that the echolocating bat controls the features of its sonar vocalizations in tandem with the positioning of the outer ears to maximize acoustic cues for target detection and localization. The bat’s adaptive control of sonar vocalizations and ear positioning occurs on a millisecond time-scale to capture spatial information from arriving echoes, as well as on a longer time-scale, to track target movement. Our results demonstrate that purposeful control over sound production and reception can serve to improve acoustic cues for localization tasks. This finding also highlights the general importance of movement to sensory processing across animal species. Finally, our discoveries point to important parallels between spatial perception by echolocation and vision