An Exploratory Multi-Session Study of Learning High-Dimensional Body-Machine Interfacing for Assistive Robot Control.

Individuals who suffer from severe paralysis often lose the capacity to perform fundamental body movements and everyday activities. Empowering these individuals with the ability to operate robotic arms, in high degrees-of-freedom (DoFs), can help to maximize both functional utility and independence. However, robot teleoperation in high DoFs currently lacks accessibility due to the challenge in capturing high-dimensional control signals from the human, especially in the face of motor impairments. Body-machine interfacing is a viable option that offers the necessary high-dimensional motion capture, and it moreover is noninvasive, affordable, and promotes movement and motor recovery. Nevertheless, to what extent body-machine interfacing is able to scale to high-DoF robot control, and whether it is feasible for humans to learn, remains an open question. In this exploratory multi-session study, we demonstrate the feasibility of human learning to operate a body-machine interface to control a complex, assistive robotic arm. We use a sensor net of four inertial measurement unit sensors, bilaterally placed on the scapulae and humeri. Ten uninjured participants are familiarized, trained, and evaluated in reaching and Activities of Daily Living tasks, using the body- machine interface. Our results suggest the manner of control space mapping (joint-space control versus task-space control), from interface to robot, plays a critical role in the evolution of human learning. Though joint-space control shows to be more intuitive initially, task-space control is found to have a greater capacity for longer-term improvement and learning.

Characterizing Eye Gaze for Assistive Device Control.

Eye gaze tracking is increasingly popular due to improved technology and availability. However, in assistive device control, eye gaze tracking is often limited to discrete control inputs. In this paper, we present a method for collecting both reactionary and control eye gaze signals to build an individualized characterization for eye gaze interface use. Results from a study conducted with motor-impaired participants are presented, offering insights into maximizing the potential of eye gaze for assistive device control. These findings can inform the development of continuous control paradigms using eye gaze.

Oxidized Phospholipid oxPAPC Alters Regulatory T-Cell Differentiation and Decreases Their Protective Function in Atherosclerosis in Mice.

BACKGROUND: Regulatory T cells (Tregs) are protective in atherosclerosis but reduced during disease progression due to cell death and loss of stability. However, the mechanisms of Treg dysfunction remain unknown. Oxidized phospholipids are abundant in atherosclerosis and can activate innate immune cells, but little is known regarding their impact on T cells. Given Treg loss during atherosclerosis progression and oxidized phospholipid levels in the plaque microenvironment, we investigated whether oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (oxPAPC), an oxidized phospholipid associated with atherosclerotic plaques, alters Treg differentiation and function. METHODS: CD4+ T cells were polarized to Treg, T helper (Th) 1, and Th17 cells with or without oxPAPC and assessed by flow cytometry. Gene expression in oxPAPC-treated Tregs was analyzed by bulk RNA sequencing. Functional studies of oxPAPC-induced Tregs were performed by coculturing Tregs with CellTrace Violet-labeled cells in vitro, and by adoptively transferring Tregs to hyperlipidemic Ldlr-/- mice to measure atherosclerosis progression. RESULTS: Compared with controls, oxPAPC-treated Tregs were less viable, but surviving cells expressed higher levels of the Th1-associated markers T-bet, CXCR3, and IFN (interferon)-γ. Th1 and Th17 skewing cultures were unaltered by oxPAPC. IFN-γ is linked to Treg instability, thus Treg polarization experiments were repeated using Ifngr1-/- CD4+ T cells. IFNγR1 (INF gamma receptor 1) deficiency did not improve cell viability in oxPAPC-treated Tregs; however, T-bet and IFN-γ expression was not increased in surviving cells suggesting a role for IFN-γsignaling. OxPAPC-treated Tregs were less suppressive in vitro, and adoptive transfer studies in hyperlipidemic Ldlr-/- mice showed that oxPAPC-induced Tregs possessed altered tissue homing and were insufficient to inhibit atherosclerosis progression. CONCLUSIONS: OxPAPC elicits Treg-specific changes altering Treg differentiation and inducing a Th1-like phenotype in surviving cells partially through IFN-γ signaling. This is biologically relevant as oxPAPC-treated Tregs do not reduce atherosclerosis progression in Ldlr-/- mice. This study supports the role of oxidized phospholipids in negatively impacting Treg differentiation and atheroprotective function.

The Impact of Control Interface on Features of Heart Rate Variability.

Shared human-robot control for assistive machines can improve the independence of individuals with motor impairments. Monitoring elevated levels of workload can enable the assistive autonomy to adjust the control sharing in an assist-as-needed way, to achieve a balance between user fatigue, stress, and independent control. In this work, we aim to investigate how heart rate variability features can be utilized to monitor elevated levels of mental workload while operating a powered wheelchair, and how that utilization might vary under different control interfaces. To that end, we conduct a 22 person study with three commercial interfaces. Our results show that the validity and reliability of using the ultra-short-term heart-rate variability features as predictors of workload indeed are affected by the type of interface in use.

The latest in systemic lupus erythematosus-accelerated atherosclerosis: related mechanisms inform assessment and therapy.

PURPOSE OF REVIEW: Accelerated atherosclerosis is a significant comorbidity and the leading cause of death for patients with systemic lupus erythematosus (SLE). It is now apparent that SLE-accelerated atherosclerosis is not driven solely by traditional cardiovascular risk factors, adding complexity to disease characterization and mechanistic understanding. In this review, we will summarize new insights into SLE-accelerated atherosclerosis evaluation, treatment, and mechanism. RECENT FINDINGS: Recent work highlights the need to incorporate inflammatory biomarkers into cardiovascular disease (CVD) risk assessments. This is especially true for SLE patients, in which mechanisms of immune dysfunction likely drive CVD progression. There is new evidence that commonly prescribed SLE therapeutics hinder atherosclerosis development. This effect is achieved both by reducing SLE-associated inflammation and by directly improving measures of atherosclerosis, emphasizing the interconnected mechanisms of the two conditions. SUMMARY: SLE-accelerated atherosclerosis is most likely the consequence of chronic autoimmune inflammation. Therefore, diligent management of atherosclerosis requires assessment of SLE disease activity as well as traditional cardiovascular risk factors. This supports why many of the therapeutics classically used to control SLE also modulate atherosclerosis development. Greater understanding of the mechanisms underlying this condition will allow for the development of more targeted therapeutics and improved outcomes for SLE patients.

Active Intent Disambiguation for Shared Control Robots.

Assistive shared-control robots have the potential to transform the lives of millions of people afflicted with severe motor impairments. The usefulness of shared-control robots typically relies on the underlying autonomy's ability to infer the user's needs and intentions, and the ability to do so unambiguously is often a limiting factor for providing appropriate assistance confidently and accurately. The contributions of this paper are four-fold. First, we introduce the idea of intent disambiguation via control mode selection, and present a mathematical formalism for the same. Second, we develop a control mode selection algorithm which selects the control mode in which the user-initiated motion helps the autonomy to maximally disambiguate user intent. Third, we present a pilot study with eight subjects to evaluate the efficacy of the disambiguation algorithm. Our results suggest that the disambiguation system (a) helps to significantly reduce task effort, as measured by number of button presses, and (b) is of greater utility for more limited control interfaces and more complex tasks. We also observe that (c) subjects demonstrated a wide range of disambiguation request behaviors, with the common thread of concentrating requests early in the execution. As our last contribution, we introduce a novel field-theoretic approach to intent inference inspired by dynamic field theory that works in tandem with the disambiguation scheme.

Interface Operation and Implications for Shared-Control Assistive Robots.

Shared-control for assistive devices can increase the independence of individuals with motor impairments. However, each person is unique in their level of injury and physical constraints. Consequently, a plethora of interfaces are used to control the assistive device, depending on the individual. In order to be effective, the shared-autonomy assistance should be aware of the usage characteristics of the interface and adjust to varying performance characteristics of the person. To that end, we conduct a 23 person (9 spinal cord injured and 14 uninjured) study using three commercial interfaces used to operate powered wheelchairs, and establish performance measures to characterize interface usage. The analyses of our performance measures unveil key aspects of the interface operation that can inform features of a customizable and interface-aware control sharing framework.

Implementation of a Perinatal Depression Care Bundle in a Nurse-Managed Midwifery Practice.

OBJECTIVE: To implement a perinatal depression care bundle at a midwifery practice to help certified nurse-midwives (CNMs) educate women about perinatal depression and direct those affected to mental health services. DESIGN: Quality improvement project to implement a perinatal depression care bundle for care of pregnant women between 24 and 29 weeks gestation. SETTING/LOCAL PROBLEM: CNMs practicing in a nurse-managed midwifery practice systematically screen all women for perinatal depression during pregnancy and the postpartum period but do not have a consistent method of providing anticipatory guidance about perinatal depression. PARTICIPANTS: All CNMs in the midwifery practice providing prenatal care (n = 16) participated in implementation. INTERVENTION/MEASUREMENTS: The perinatal depression care bundle included three elements: (a) an educational handout; (b) a brief, provider-initiated discussion about perinatal depression; and (c) lists of local and online mental health resources. Four weeks after the care bundle was implemented, we conducted a retrospective chart review to assess CNMs' adherence to the new bundle. RESULTS: Over 4 weeks, 51 prenatal visits met eligibility criteria for participation. CNMs implemented the perinatal depression care bundle for 22 (43.1%) eligible visits. CNM feedback indicated that the care bundle was brief, easy to incorporate into routine care, and well received by women. CONCLUSION: This project incorporated the use of a perinatal depression care bundle for women seen during routine prenatal care. Using a systematic approach to deliver perinatal depression education and resources reduces process variability and may destigmatize the illness, allowing women to feel empowered to seek help before depression symptoms become severe.

Group-based interventions for postpartum depression: An integrative review and conceptual model.

This integrative review explores how and to what extent group-based therapy and social support interventions affect women's recovery from postpartum depression (PPD). Thirteen articles from three databases met inclusion criteria. The studies revealed that a group environment of acceptance and understanding set a foundation for women to share their experiences with PPD. As women shared challenges, wisdom, and guidance within the group, they attained positive outcomes: validation, empowerment, and improvements in depressive symptoms. An integrated conceptual model was created to depict the identified characteristics and outcomes of PPD groups; clinicians can use the model to optimize group-based PPD interventions.

Autonomy in Rehabilitation Robotics: An Intersection.

Within the field of human rehabilitation, robotic machines are used both to rehabilitate the body and to perform functional tasks. Robotics autonomy able to perceive the external world and reason about high-level control decisions, however, seldom is present in these machines. For functional tasks in particular, autonomy could help to decrease the operational burden on the human and perhaps even to increase access-and this potential only grows as human motor impairments become more severe. There are however serious, and often subtle, considerations to introducing clinically-feasible robotics autonomy to rehabilitation robots and machines. Today the fields of robotics autonomy and rehabilitation robotics are largely separate. The topic of this article is at the intersection of these fields: the introduction of clinically-feasible autonomy solutions to rehabilitation robots, and opportunities for autonomy within the rehabilitation domain.

Prediction of user preference over shared-control paradigms for a robotic wheelchair.

The design of intelligent powered wheelchairs has traditionally focused heavily on providing effective and efficient navigation assistance. Significantly less attention has been given to the end-user's preference between different assistance paradigms. It is possible to include these subjective evaluations in the design process, for example by soliciting feedback in post-experiment questionnaires. However, constantly querying the user for feedback during real-world operation is not practical. In this paper, we present a model that correlates objective performance metrics and subjective evaluations of autonomous wheelchair control paradigms. Using off-the-shelf machine learning techniques, we show that it is possible to build a model that can predict the most preferred shared-control method from task execution metrics such as effort, safety, performance and utilization. We further characterize the relative contributions of each of these metrics to the individual choice of most preferred assistance paradigm. Our evaluation includes Spinal Cord Injured (SCI) and uninjured subject groups. The results show that our proposed correlation model enables the continuous tracking of user preference and offers the possibility of autonomy that is customized to each user.

A Human-Robot Interaction Perspective on Assistive and Rehabilitation Robotics.

Assistive and rehabilitation devices are a promising and challenging field of recent robotics research. Motivated by societal needs such as aging populations, such devices can support motor functionality and subject training. The design, control, sensing, and assessment of the devices become more sophisticated due to a human in the loop. This paper gives a human-robot interaction perspective on current issues and opportunities in the field. On the topic of control and machine learning, approaches that support but do not distract subjects are reviewed. Options to provide sensory user feedback that are currently missing from robotic devices are outlined. Parallels between device acceptance and affective computing are made. Furthermore, requirements for functional assessment protocols that relate to real-world tasks are discussed. In all topic areas, the design of human-oriented frameworks and methods is dominated by challenges related to the close interaction between the human and robotic device. This paper discusses the aforementioned aspects in order to open up new perspectives for future robotic solutions.

Iron catalyzed diastereoselective hydrogenation of chiral imines.

Cyclopentadienone-based iron complexes were used for the first time to successfully catalyze the diastereoselective hydrogenation of enantiopure imines. Chiral amines, including valuable biologically active products, were obtained often as enantiomerically pure compounds. Computational studies helped to elucidate the chemical and stereochemical aspects of the iron-catalyzed reaction.

Human-in-the-Loop Optimization of Shared Autonomy in Assistive Robotics.

In this paper, we propose a mathematical framework which formalizes user-driven customization of shared autonomy in assistive robotics as a nonlinear optimization problem. Our insight is to allow the end-user, rather than relying on standard optimization techniques, to perform the optimization procedure, thereby allowing us to leave the exact nature of the cost function indeterminate. We ground our formalism with an interactive optimization procedure that customizes control sharing using an assistive robotic arm. We also present a pilot study that explores interactive optimization with end-users. This study was performed with 17 subjects (4 with spinal cord injury, 13 without injury). Results show all subjects were able to converge to an assistance paradigm, suggesting the existence of optimal solutions. Notably, the amount of assistance was not always optimized for task performance. Instead, some subjects favored retaining more control during the execution over better task performance. The study supports the case for user-driven customization and provides guidance for its continued development and study.

The Influence of Nutrition Label Placement on Awareness and Use among College Students in a Dining Hall Setting.

BACKGROUND: Nutrition labels may be important predictors of dietary selections among college students; however, awareness and use are not well understood in this population. OBJECTIVE: The aim of this work was to investigate the influence of label placement on label awareness and use, including influences over time. We also aimed to identify predictors of awareness and use, preferred label information, and reasons for label nonuse. DESIGN: Cross-sectional surveys were administered in three 1-week waves over 3 months. PARTICIPANTS/SETTING: Two thousand seven hundred twenty-nine students aged 18 years or older in four university dining halls. INTERVENTION: Nutrition labels were placed on sneeze guards in two dining halls and directly in front of food in two comparator dining halls. MAIN OUTCOME MEASURES: Label awareness and use were measured using 5-point Likert scales. Reasons for label nonuse and preferred types of information were assessed by response frequencies. STATISTICAL ANALYSIS PERFORMED: Logistic regression was used to determine predictors of label awareness and use. To test for differences in information preferences between label users and nonusers, χ(2) tests were used. RESULTS: Nutrition label awareness and use did not vary by label placement or over time. Awareness was related to being obese, having higher perceived stress, taking nutrition classes, having good/excellent eating habits, eating breakfast, tracking food intake, and exercising five or more times per week. Use was related to being a woman, being overweight, having higher perceived stress, having good/excellent eating habits, eating breakfast, tracking food intake, and exercising three or more times per week. Information preferences differed by use, but calories, fat, and protein were the most preferred pieces of information overall. Not caring, already having a good idea about nutrition information, and not having time were the top reasons for label nonuse. CONCLUSIONS: Label awareness and use did not change with label placement or over time. Making labels easy to read and including preferred information may encourage greater awareness and use.

Improvements in recall and food choices using a graphical method to deliver information of select nutrients.

Consumers have difficulty using nutrition information. We hypothesized that graphically delivering information of select nutrients relative to a target would allow individuals to process information in time-constrained settings more effectively than numerical information. Objectives of the study were to determine the efficacy of the graphical method in (1) improving memory of nutrient information and (2) improving consumer purchasing behavior in a restaurant. Values of fiber and protein per calorie were 2-dimensionally plotted alongside a target box. First, a randomized cued recall experiment was conducted (n=63). Recall accuracy of nutrition information improved by up to 43% when shown graphically instead of numerically. Second, the impact of graphical nutrition signposting on diner choices was tested in a cafeteria. Saturated fat and sodium information was also presented using color coding. Nutrient content of meals (n=362) was compared between 3 signposting phases: graphical, nutrition facts panels (NFP), or no nutrition label. Graphical signposting improved nutrient content of purchases in the intended direction, whereas NFP had no effect compared with the baseline. Calories ordered from total meals, entrées, and sides were significantly less during graphical signposting than no-label and NFP periods. For total meal and entrées, protein per calorie purchased was significantly higher and saturated fat significantly lower during graphical signposting than the other phases. Graphical signposting remained a predictor of calories and protein per calorie purchased in regression modeling. These findings demonstrate that graphically presenting nutrition information makes that information more available for decision making and influences behavior change in a realistic setting.

Suspicion of Motives Predicts Minorities' Responses to Positive Feedback in Interracial Interactions.

Strong social and legal norms in the United States discourage the overt expression of bias against ethnic and racial minorities, increasing the attributional ambiguity of Whites' positive behavior to ethnic minorities. Minorities who suspect that Whites' positive overtures toward minorities are motivated more by their fear of appearing racist than by egalitarian attitudes may regard positive feedback they receive from Whites as disingenuous. This may lead them to react to such feedback with feelings of uncertainty and threat. Three studies examined how suspicion of motives relates to ethnic minorities' responses to receiving positive feedback from a White peer or same-ethnicity peer (Experiment 1), to receiving feedback from a White peer that was positive or negative (Experiment 2), and to receiving positive feedback from a White peer who did or did not know their ethnicity (Experiment 3). As predicted, the more suspicious Latinas were of Whites' motives for behaving positively toward minorities in general, the more they regarded positive feedback from a White peer who knew their ethnicity as disingenuous and the more they reacted with cardiovascular reactivity characteristic of threat/avoidance, increased feelings of stress, heightened uncertainty, and decreased self-esteem. We discuss the implications for intergroup interactions of perceptions of Whites' motives for nonprejudiced behavior.

Using machine learning to blend human and robot controls for assisted wheelchair navigation.

This work presents an algorithm for collaborative control of an assistive semi-autonomous wheelchair. Our approach is based on a statistical machine learning technique to learn task variability from demonstration examples. The algorithm has been developed in the context of shared-control powered wheelchairs that provide assistance to individuals with impairments that affect their control in challenging driving scenarios, like doorway navigation. We validate our algorithm within a simulation environment, and find that with relatively few demonstrations, our approach allows for safe traversal of the doorway while maintaining a high level of user control.