50 research outputs found

    An Introduction to Causal Inference Methods for Observational Human-Robot Interaction Research

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    Quantitative methods in Human-Robot Interaction (HRI) research have primarily relied upon randomized, controlled experiments in laboratory settings. However, such experiments are not always feasible when external validity, ethical constraints, and ease of data collection are of concern. Furthermore, as consumer robots become increasingly available, increasing amounts of real-world data will be available to HRI researchers, which prompts the need for quantative approaches tailored to the analysis of observational data. In this article, we present an alternate approach towards quantitative research for HRI researchers using methods from causal inference that can enable researchers to identify causal relationships in observational settings where randomized, controlled experiments cannot be run. We highlight different scenarios that HRI research with consumer household robots may involve to contextualize how methods from causal inference can be applied to observational HRI research. We then provide a tutorial summarizing key concepts from causal inference using a graphical model perspective and link to code examples throughout the article, which are available at https://gitlab.com/causal/causal_hri. Our work paves the way for further discussion on new approaches towards observational HRI research while providing a starting point for HRI researchers to add causal inference techniques to their analytical toolbox.Comment: 28 page

    Modelling the effect of hydrogen on crack growth in zirconium

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    Via molecular dynamics simulations, the effects of hydrogen on stress evolution of -zirconium and crack propagation in monocrystalline and multiple grained zirconium systems are investigated. Diffusion barriers are shown to reduce when strain is applied, which then causes hydrogen to accumulate at surfaces and grain boundaries. Crack growth is considered for a range of -zirconium systems, both with and without hydrogen, strained in multiple directions. The effects of crystal orientation are shown to be of high influence on the stress evolution of -zirconium irrespective of hydrogen content. Crack growth velocity is increased the most by hydrogen for -zirconium when uniaxial strain is applied in the [0 0 0 1] direction. Simulations are conducted investigating the effects of single grain boundaries in normal and parallel orientations to crack growth showing a high importance on the location of interstitial hydrogen in crack growth behaviour. In addition, larger scale simulations show the effects of multiple grain boundaries and hydrogen content in the evolution of cracks

    Controlled induction of human pancreatic progenitors produces functional beta‐like cells in vitro

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    Directed differentiation of human pluripotent stem cells into functional insulin‐producing beta‐like cells holds great promise for cell replacement therapy for patients suffering from diabetes. This approach also offers the unique opportunity to study otherwise inaccessible aspects of human beta cell development and function in vitro. Here, we show that current pancreatic progenitor differentiation protocols promote precocious endocrine commitment, ultimately resulting in the generation of non‐functional polyhormonal cells. Omission of commonly used BMP inhibitors during pancreatic specification prevents precocious endocrine formation while treatment with retinoic acid followed by combined EGF/KGF efficiently generates both PDX1+ and subsequent PDX1+/NKX6.1+ pancreatic progenitor populations, respectively. Precise temporal activation of endocrine differentiation in PDX1+/NKX6.1+ progenitors produces glucose‐responsive beta‐like cells in vitro that exhibit key features of bona fide human beta cells, remain functional after short‐term transplantation, and reduce blood glucose levels in diabetic mice. Thus, our simplified and scalable system accurately recapitulates key steps of human pancreas development and provides a fast and reproducible supply of functional human beta‐like cells.SynopsisFocusing on developmental mechanisms, the results of this study further accelerate successful differentiation of human ESCs into functional pancreatic beta cells.Exclusion of commonly used BMP inhibitors during human embryonic stem cell to pancreatic progenitor differentiation prevents precocious endocrine induction.Sequential exposure of foregut cells to retinoic acid followed by combined EGF/KGF treatment establishes highly pure PDX1+ and PDX1+/NKX6.1+ progenitor populations, respectively.Precise temporal induction of endocrine differentiation in PDX1+/NKX6.1+ progenitors, but not in PDX1+/NKX6.1− progenitors, results in the generation of functional beta‐like cells in vitro.Beta‐like cells exhibit key features of bona fide human beta cells, remain functional after short‐term transplantation, and reduce blood glucose levels in diabetic mice.Focusing on developmental mechanisms, the results of this study further accelerate successful differentiation of human ESCs into functional pancreatic beta cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111932/1/embj201591058.reviewer_comments.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/111932/2/embj201591058.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/111932/3/embj201591058-sup-0001-FigsS1-S4.pd

    Potential benefits and therapeutic applications of "Panchgavya" therapy (Cowpathy) for human and animal health: Current scientific knowledge

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    Cow's milk, urine, dung, ghee, and curd (together known as "Panchgavya") have incomparable medicinal value in Ayurveda and ancient Indian clinical methods. Panchgavya is also known as Cowpathy in Ayurveda. In India, the cow is revered as a goddess known as "Gaumata" because of its nurturing qualities similar to those of a mother. Almost no adverse effects are associated with using Panchgavya, which is why it is recommended in Ayurveda for treating disorders affecting numerous body systems. Its possible antimicrobial effects have piqued the curiosity of medical researchers and practitioners. Cow milk is widely regarded as a nutritious diet and has been shown to effectively treat various medical conditions, including high body temperature, pain, cancer, diabetes, kidney diseases, and weakness. Milk can prevent the growth of microorganisms, has erotic qualities when combined with the leaves of medicinal herbs, and the fat in milk has anticancer characteristics. Toned and skim milk, lassi, yoghurt, cottage cheese, and khoa all come from milk and have important medicinal characteristics. Curd (dahi) is recommended as a blood purifier for conditions such as hemorrhoids, piles, and gastrointestinal issues. Ghee made from cows has been shown to boost immunity. It is important to highlight the use of cow dung as an antifungal and for treating malaria and tuberculosis. It has the potential to aid in the development of a populace free from disease, the creation of sustainable energy systems, the fulfilment of all nutritional needs, the elimination of poverty, the promotion of organic farming culture, and the like. Cow urine is a powerful remedy for numerous medical conditions, including but not limited to epileptic convulsions, diabetes, hepatitis, inflammation, fever, and anaemia. The current review article explores how the Panchgavya ingredients can be employed to safeguard human and animal health

    VEGF Stimulates Activation of ERK5 in the Absence of C-Terminal Phosphorylation Preventing Nuclear Localization and Facilitating AKT Activation in Endothelial Cells

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    Extracellular-signal-regulated kinase 5 (ERK5) is critical for normal cardiovascular development. Previous studies have defined a canonical pathway for ERK5 activation, showing that ligand stimulation leads to MEK5 activation resulting in dual phosphorylation of ERK5 on Thr218/Tyr220 residues within the activation loop. ERK5 then undergoes a conformational change, facilitating phosphorylation on residues in the C-terminal domain and translocation to the nucleus where it regulates MEF2 transcriptional activity. Our previous research into the importance of ERK5 in endothelial cells highlighted its role in VEGF-mediated tubular morphogenesis and cell survival, suggesting that ERK5 played a unique role in endothelial cells. Our current data show that in contrast to EGF-stimulated HeLa cells, VEGF-mediated ERK5 activation in human dermal microvascular endothelial cells (HDMECs) does not result in C-terminal phosphorylation of ERK5 and translocation to the nucleus, but instead to a more plasma membrane/cytoplasmic localisation. Furthermore, the use of small-molecule inhibitors to MEK5 and ERK5 shows that instead of regulating MEF2 activity, VEGF-mediated ERK5 is important for regulating AKT activity. Our data define a novel pathway for ERK5 activation in endothelial cells leading to cell survival

    The role of ERK5 in endothelial cell function

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    Extracellular-signal-regulated kinase 5 (ERK5), also termed big MAPK1 (BMK1), is the most recently discovered member of the mitogen-activated protein kinase (MAPK) family. It is expressed in a variety of tissues and is activated by a range of growth factors, cytokines and cellular stresses. Targeted deletion of Erk5 in mice has revealed that the ERK5 signalling cascade is critical for normal cardiovascular development and vascular integrity. In vitro studies have revealed that, in endothelial cells, ERK5 is required for preventing apoptosis, mediating shear-stress signalling and regulating tumour angiogenesis. The present review focuses on our current understanding of the role of ERK5 in regulating endothelial cell function

    Resistance against ostracization: An unbiased analysis on the institutional treatment of tribal groups as portrayed in Jai Bhim

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    Jai Bhim (2021), directed by T J Gnanavel, has piqued the interest of a broader audience due to its incisively political message as well as the title. One may envisage using the iconic Ambedkarite phrase to commodify Ambedkarite politics and exploit it for corporate goals. However, a more complex and controversial perspective of the film emerges after a deeper screening. The present research applies resistance theory to the political context within the film, namely the caste-based layering. Individuals sometimes strive to denigrate or look down on persons from the so-called lower castes. Such activities are frowned upon in the film, and they should be stopped in real life as well
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