Learning a Motor Grammar of Iconic Gestures

Sadeghipour A, Kopp S. Learning a Motor Grammar of Iconic Gestures. In: Proceedings of the 35th Annual Meeting of the Cognitive Science Society (CogSci 2013). Austin, TX: Cognitive Science Society; 2014: 1341-1346

3D Iconic Gesture Dataset

Sadeghipour A, Morency L-P. 3D Iconic Gesture Dataset. University of Southern California; 2011.Iconic gestures are pictorial gestures, which depict entities, objects or actions. Humans perform iconic gestures to refer to entities through embodying their shapes. For instance, people often gesture the outline of an object (e.g. a circle for a ball) when referring to it during communication. 29 subjects (20 males and 9 females) were asked to perform gestures to refer to 20 different virtual 3D objects. Using MS Kinect™, in total 1739 gesture performances were captured each in three formats: color video, depth video and motion of the tracked skeleton (as 3D positions of 20 joints in 30 fps). Project website: http://projects.ict.usc.edu/3dig

Gesture-based Object Recognition using Histograms of Guiding Strokes

Sadeghipour A, Morency L-P, Kopp S. Gesture-based Object Recognition using Histograms of Guiding Strokes. In: Bowden R, Collomosse J, Mikolajczyk K, eds. Proceedings of the British Machine Vision Conference. BMVA Press; 2012: 44.1-44.11

Side-hole catheters have higher thrombus aspiration efficiency than regular end-hole catheters in an in vitro model

PURPOSEWe aimed to evaluate and compare thrombus aspiration efficiency between side-hole and end-hole thrombus-aspirating catheters.METHODSUsing an in vitro model of acute thrombus occlusion, we performed thrombus aspiration with two catheter designs. Two end-hole and two side-hole catheters, 8 F and 10 F in diameter, were examined. Thrombus aspiration was performed with each catheter 30 times, and the amount of thrombotic material aspirated in each attempt was determined. The mean weight of the thrombotic material and the mean weight of the non-fluid thrombotic material extracted in all 30 attempts by each catheter were also determined.RESULTSThe 10 F side-hole catheter aspirated more thrombotic material than did the 10 F end-hole catheter (44.76 g vs. 28.35 g). The 8 F side-hole catheter had higher thrombus aspiration capacity than did the 8 F end-hole catheter in terms of the mean weight of the aspirated thrombus at each aspiration attempt (1.41 g vs. 0.58 g; P < 0.001) and the mean volume of the aspirated thrombotic material at each aspiration attempt (1.79 mL vs. 1.01 mL; P < 0.001). The mean weight of the non-fluid thrombotic material aspirated with the side-hole catheters was higher than that aspirated by the end-hole catheters with the same diameter size (31.06 g vs. 22.41 g for the 10 F catheters; P < 0.001; and 4.54 g vs. 2.99 g for the 8 F catheters; P < 0.001).CONCLUSIONSide-hole catheters are more effective in aspirating acute thrombi. The added benefit of the side-hole design is more remarkable in smaller-sized catheters. Animal models are needed to examine their aspiration capacity in a real elastic vascular conduit and in the presence of wall-adherent thrombi

Association between serum vitamin D, hs-CRP, and prooxidant-antioxidant balance with anthropometric and biochemical parameters in patients with diabetic foot ulcers

Background. Oxidative balance and inflammatory processes affect wound healing phases, and their disruption is connected with delayed wound healing. The present study aimed to assess the association between serum hs-CRP, prooxidant-antioxidant Balance (PAB), and vitamin D with anthropometric and biochemical parameters in patients with diabetic foot ulcers (DFU).Methods. Thirty-two patients with DFU were included in this study. The Spearman correlation coefficient was used to evaluate the bivariate relationship between serum hs-CRP, PAB, and vitamin D with anthropometric characteristics, glycemic status, lipid profiles, homocysteine level, liver, and kidney function tests.Results. Our data showed a significant positive association between serum hs-CRP and insulin (r = 0.417, P = 0.027), uric acid (r = 0.629, P = 0.001), creatinine (r = 0.431, P = 0.022), erythema (r = 0.36, P = 0.049), and ESR (r = 0.560, P = 0.002). Moreover, hs-CRP negatively correlated with FBS (r = –0.427, P = 0.023), total bilirubin (r = –0.639, P = 0.001), direct bilirubin (r = –0.445, P = 0.033), LDL-cholesterol (r = –0.405, P = –0.032), BMI (r = –0.398, P = 0.033) and HTN (r = –0.450, P = 0.014). Serum PAB value negatively correlated with patients age (r = –0.460, P = 0.027), and BMI (r = –0.442, P = 0.035), and positively associated with insulin level (r = 0.431, P = 0.040). A significant positive association between serum vitamin D with patient sex (r = 0.379, P = 0.047), and QUICKI (r = 0.456, P = 0.029), and negative correlation with HbA1c (r = –0.381, P = 0.045) were also determined.Conclusions. This study demonstrated that serum hs- CRP, PAB, and vitamin D are significantly associated with some anthropometric and biochemical parameters with important clinical value in patients with DFU. Low levels of vitamin D and high levels of hs-CRP and PAB may have an important role in the pathogenesis of DFU

Embodied Gesture Processing: Motor-Based Integration of Perception and Action in Social Artificial Agents

A close coupling of perception and action processes is assumed to play an important role in basic capabilities of social interaction, such as guiding attention and observation of others’ behavior, coordinating the form and functions of behavior, or grounding the understanding of others’ behavior in one’s own experiences. In the attempt to endow artificial embodied agents with similar abilities, we present a probabilistic model for the integration of perception and generation of hand-arm gestures via a hierarchy of shared motor representations, allowing for combined bottom-up and top-down processing. Results from human-agent interactions are reported demonstrating the model’s performance in learning, observation, imitation, and generation of gestures

Embodied Behavior Processing in ECAs by Perception-Action Integration

Sadeghipour A, Kopp S. Embodied Behavior Processing in ECAs by Perception-Action Integration. Presented at the CHI 2011 Workshop: Embodied Interaction: Theory and Practice in HCI, Vancouver, BC, Canada.Perception and generation of verbal and nonverbal behavior is one of the main foundations of human social interaction. We model these abilities for embodied conversational agents (ECAs) on the basis of perception-action links as in humans. With a focus on gesture processing, we propose a computational model which enables ECAs to interact with humans in an embodied manner and supports many aspects of social interaction. The model performance is briefly illustrated on the basis of an interaction scene

A Computational Cognitive Model for Embodied Processing of Iconic Gestures

Sadeghipour A. A Computational Cognitive Model for Embodied Processing of Iconic Gestures. Aachen: Shaker; 2015.In this PhD thesis, I propose a computational cognitive model for processing iconic gestures performed with hands and arms. Among different social behaviors, investigating gestures has gained special attention during the last decades. In the field of human-computer interaction, advances in motion tracking systems have opened the gateway to the broader application of gesture-based user interfaces. Virtual humanoid agents are been increasingly used in human-computer interaction as user friendly interfaces that allow for intuitive and natural face-to-face communication. Against this background, I propose a model that endows artificial humanoid agents with the ability to gesture. This capacity includes, for instance, fast and reliable recognition of highly diverse gesture performances, the ability to learn how to perform gestures through imitation, and to establish gestural alignment during interaction with human users. To this end, I propose a cognitive model of the human sensorimotor system based on neuroscience and psychological empirical evidence, and couched in current cognitive theories. To implement information processing within this cognitive model, I propose two computational approaches with complementary strengths and weaknesses: (1) Empirical Bayesian Belief Update (EBBU) features the fast, incremental and cognitively plausible recognition of gestures during interaction with humans. (2) Feature-based Stochastic Context-Free Grammar (FSCFG) learns discriminative or descriptive grammar models of gesture performances