26 research outputs found
Investigating Looking Behaviors with a Humanoid Robot
Faculty advisor: Jed ElisonSeveral research studies have shown that children with autism spectrum disorders (ASD) often display impairments in their ability to engage in many social behaviors that are crucial for the development of social-emotional competence, empathy, and expressive language. Because most children with autism show strong preferences for nonsocial information such as objects and machines (Adamson, Deckner, & Bakeman, 2010; Tapus et al., 2012), researchers have explored using humanoid robots to help children with autism develop skills for social interaction (Tapus et al., 2012). In this study, we used data from 55 typically developing toddlers (M= 33 months) who participated in a 10-minute semi-structured play session with a humanoid robot, the NAO V4 (Aldebaran Robotics). The NAO robot was pre-programmed to advance through seven structured social interactions, such as Simon Says, I Spy, a tai chi routine, and a dance to “If You’re Happy and You Know It.” Using this data, we examined children’s engagement with the robot, specifically their looking preferences during the interaction phases with the NAO.This research was supported by the Undergraduate Research Opportunities Program (UROP)
Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study
BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348
Leveraging Computer Vision and Humanoid Robots to Detect Autism in Toddlers
University of Minnesota Ph.D. dissertation. December 2018. Major: Computer Science. Advisor: Maria Gini. 1 computer file (PDF); xvi, 150 pages.Autism Spectrum Disorder is a developmental disorder often characterized by limited social skills, repetitive behaviors, obsessions, and/or routines. Early intervention significantly improves long-term outcomes for toddlers identified in the second year of life and is the best approach for affecting lasting positive change for children with an ASD. Research shows that children with autism especially enjoy technology, including autonomous (or seemingly autonomous) robots. Tying these together, we hypothesize that observing play interactions between very young children (2 - 4 years old) and a humanoid robot can help us identify children with autism; this first requires us to generate a very large, thoroughly characterized dataset of typically developing children. We begin with an eye tracking experiment comparing four different robots and a young human peer; this shows us which type of robot may be of most interest to children in an in-person, real-life play scenario, and if that robot is as interesting as a peer. Using the robot found to be most interesting in the eye tracking experiment, we next detail a human-robot interaction experiment that engages 2 - 4 year old children in a series of social games with a small humanoid robot; we then analyze the social distances, or proxemics, of the child throughout the interaction. To generate the proxemics data, we use a highly automated person detector which utilizes two state-of-the-art convolutional neural networks; with the proxemics and other development assessment data, we compare and group participants and discuss the implications of those results. A subset of robot interaction participants also finished the eye tracking task, so we discuss the relationship between the human-robot interactions and eye tracking results. Lastly, to validate the generalizability of our automated tracker, we test the system on two other child development experiments, a multiple-participant in-group bias play scenario for 5 and 8 year old children, and an unsolvable box task for toddlers
Building polymer-like clusters from colloidal particles with isotropic interactions, in aqueous solution
Hypothesis: Colloidal particles that interact via a long-ranged repulsive barrier in combination with a very short-ranged attractive minimum can “polymerize” to form highly anisotropic structures. Motivated by previous experimental achievements in non-aqueous solvents, and recent theoretical predictions, we hypothesize that it is possible to construct clusters that resemble linear or branched polymers, in aqueous solution. If these clusters are not too large, they may even remain dispersed, but even if they grow large enough to sediment, they may be collected and used in future applications.Experiments: In this work, we specifically synthesize poly (ethylene glycol) (PEG) chains, grafted onto poly(styrene) (PS) particles in aqueous solution, and adjust the conditions so that strongly anisotropic and isolated polymer-like clusters are formed. These conditions include a very low ionic strength (the particles are weakly charged), a relatively high temperature, and a low particle concentration. An important criterion is that the particle size is large enough to admit structural analyses via confocal laser scanning microscopy (CLSM). We have furthermore utilized Metropolis Monte Carlo (MC) simulation to generate theoretical predictions of these cluster formations. We have conducted such simulations of 3D as well as 2D systems, where the latter is also relevant, given that the clusters sometimes deposit onto the glass surfaces upon imaging. A simplistic particle–particle potential of mean force is adopted for the simulations, but we also invoke a more elaborate theoretical model, to demonstrate that similar interactions can be obtained when the grafted chains are treated explicitly.Findings: According to our Zeta potential measurements, the particles indeed carry a weak negative charge, presumably due to ion specific adsorption. Furthermore, by ensuring that the ionic strength is very low, with a Debye length similar to the particle size, we could use temperature to control the hydrophobicity of the grafted PEG layer, and thus the strength of the short-ranged attraction. We were indeed able to establish highly anisotropic structures, that resemble linear or branched polymers, which we could image by CLSM. The average degree of polymerization could be adjusted by a variation of the particle concentration
An Examination of Recording Accuracy and Precision From Eye Tracking Data From Toddlerhood to Adulthood
The quantitative assessment of eye tracking data quality is critical for ensuring accuracy and precision of gaze position measurements. However, researchers often report the eye tracker’s optimal manufacturer’s specifications rather than empirical data about the accuracy and precision of the eye tracking data being presented. Indeed, a recent report indicates that less than half of eye tracking researchers surveyed take the eye tracker’s accuracy into account when determining areas of interest for analysis, an oversight that could impact the validity of reported results and conclusions. Accordingly, we designed a calibration verification protocol to augment independent quality assessment of eye tracking data and examined whether accuracy and precision varied between three age groups of participants. We also examined the degree to which our externally quantified quality assurance metrics aligned with those reported by the manufacturer. We collected data in standard laboratory conditions to demonstrate our method, to illustrate how data quality can vary with participant age, and to give a simple example of the degree to which data quality can differ from manufacturer reported values. In the sample data we collected, accuracy for adults was within the range advertised by the manufacturer, but for school-aged children, accuracy and precision measures were outside this range. Data from toddlers were less accurate and less precise than data from adults. Based on an a priori inclusion criterion, we determined that we could exclude approximately 20% of toddler participants for poor calibration quality quantified using our calibration assessment protocol. We recommend implementing and reporting quality assessment protocols for any eye tracking tasks with participants of any age or developmental ability. We conclude with general observations about our data, recommendations for what factors to consider when establishing data inclusion criteria, and suggestions for stimulus design that can help accommodate variability in calibration. The methods outlined here may be particularly useful for developmental psychologists who use eye tracking as a tool, but who are not experts in eye tracking per se. The calibration verification stimuli and data processing scripts that we developed, along with step-by-step instructions, are freely available for other researchers
Image_2_An Examination of Recording Accuracy and Precision From Eye Tracking Data From Toddlerhood to Adulthood.PDF
<p>The quantitative assessment of eye tracking data quality is critical for ensuring accuracy and precision of gaze position measurements. However, researchers often report the eye tracker’s optimal manufacturer’s specifications rather than empirical data about the accuracy and precision of the eye tracking data being presented. Indeed, a recent report indicates that less than half of eye tracking researchers surveyed take the eye tracker’s accuracy into account when determining areas of interest for analysis, an oversight that could impact the validity of reported results and conclusions. Accordingly, we designed a calibration verification protocol to augment independent quality assessment of eye tracking data and examined whether accuracy and precision varied between three age groups of participants. We also examined the degree to which our externally quantified quality assurance metrics aligned with those reported by the manufacturer. We collected data in standard laboratory conditions to demonstrate our method, to illustrate how data quality can vary with participant age, and to give a simple example of the degree to which data quality can differ from manufacturer reported values. In the sample data we collected, accuracy for adults was within the range advertised by the manufacturer, but for school-aged children, accuracy and precision measures were outside this range. Data from toddlers were less accurate and less precise than data from adults. Based on an a priori inclusion criterion, we determined that we could exclude approximately 20% of toddler participants for poor calibration quality quantified using our calibration assessment protocol. We recommend implementing and reporting quality assessment protocols for any eye tracking tasks with participants of any age or developmental ability. We conclude with general observations about our data, recommendations for what factors to consider when establishing data inclusion criteria, and suggestions for stimulus design that can help accommodate variability in calibration. The methods outlined here may be particularly useful for developmental psychologists who use eye tracking as a tool, but who are not experts in eye tracking per se. The calibration verification stimuli and data processing scripts that we developed, along with step-by-step instructions, are freely available for other researchers.</p
Building polymer-like clusters from colloidal particles with isotropic interactions, in aqueous solution
Electroweak parameters of the z0 resonance and the standard model
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Measurement of the Mass of the Z-Boson and the Energy Calibration of Lep
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