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Peroxisomes are key regulators of cellular and metabolic homeostasis. These organelles play important roles in redox metabolism, the oxidation of very-long-chain fatty acids (VLCFAs), and the biosynthesis of ether phospholipids. Given the essential role of peroxisomes in cellular homeostasis, peroxisomal dysfunction has been linked to various pathological conditions, tissue functional decline, and aging. In the past few decades, a variety of cellular signaling and metabolic changes have been reported to be associated with defective peroxisomes, suggesting that many cellular processes and functions depend on peroxisomes. Peroxisomes communicate with other subcellular organelles, such as the nucleus, mitochondria, endoplasmic reticulum (ER), and lysosomes. These inter-organelle communications are highly linked to the key mechanisms by which cells surveil defective peroxisomes and mount adaptive responses to protect them from damages. In this review, we highlight the major cellular changes that accompany peroxisomal dysfunction and peroxisomal inter-organelle communication through membrane contact sites, metabolic signaling, and retrograde signaling. We also discuss the age-related decline of peroxisomal protein import and its role in animal aging and age-related diseases. Unlike other organelle stress response pathways, such as the unfolded protein response (UPR) in the ER and mitochondria, the cellular signaling pathways that mediate stress responses to malfunctioning peroxisomes have not been systematically studied and investigated. Here, we coin these signaling pathways as “peroxisomal stress response pathways”. Understanding peroxisomal stress response pathways and how peroxisomes communicate with other organelles are important and emerging areas of peroxisome research. 

We present the results of photometric and spectroscopic monitoring campaigns of the changing look AGN NGC 2617 carried out from 2016 until 2022 and covering the wavelength range from the X-ray to the near-IR. The facilities included the telescopes of the SAI MSU, MASTER Global Robotic Net, the 2.3-m WIRO telescope, Swift, and others. We found significant variability at all wavelengths and, specifically, in the intensities and profiles of the broad Balmer lines. We measured time delays of ∼6 d (∼8 d) in the responses of the Hβ (Hα) line to continuum variations. We found the X-ray variations to correlate well with the UV and optical (with a small time delay of a few days for longer wavelengths). The K-band lagged the B band by 14 ± 4 d during the last three seasons, which is significantly shorter than the delays reported previously by the 2016 and 2017–2019 campaigns. Near-IR variability arises from two different emission regions: the outer part of the accretion disc and a more distant dust component. The HK-band variability is governed primarily by dust. The Balmer decrement of the broad-line components is inversely correlated with the UV flux. The change of the object’s type from Sy1 to Sy1.8 was recorded over a period of ∼8 yr. We interpret these changes as a combination of two factors: changes in the accretion rate and dust recovery along the line of sight.

 

The field of Mechatronics and Robotics Engineering (MRE) is emerging as a distinct academic discipline. Previously, courses in this field have been housed in departments of Mechanical Engineering, Electrical Engineering, or Computer Science, instead of a standalone department or curriculum. More recently, single, freestanding courses have increasingly grown into course sequences and concentrations, with entire baccalaureate and graduate degree programs now being offered. The field has been legitimized in recent years with the National Center for Education Statistics creating the Classification of Instructional Programs (CIP) code 14.201 Mechatronics, Robotics, and Automation Engineering. As of October 2019, ABET accredits a total of 9 B.S. programs in the field: 5 Mechatronics Engineering, 3 Robotics Engineering, 1 Mechatronics and Robotics Engineering, and none in Automation Engineering. Despite recent tremendous and dynamic growth, MRE lacks a dedicated professional organization and has no discipline-specific ABET criteria. As the field grows more important and widespread, it becomes increasingly relevant to formalize and standardize the curricula of these programs. This paper begins a conversation about the contents of a cohesive concept inventory for MRE. The impetus for this effort grew from a set of four industry and government sponsored workshops held around the country named the Future of Mechatronics and Robotics Engineering (FoMRE). These workshops brought together multidisciplinary academic professionals and industry leaders in the field, and ran from September 2018 to September 2019. The study presented here focuses primarily on programs at the baccalaureate level, but informs discussion at the graduate level as well. A survey is prepared with lists of potential concept inventory items, and asks university faculty, students and practicing engineers to identify which concepts lie at the core of MRE. Because of the interdisciplinary nature of the field, a wide range of basic concepts including physical quantities and units, circuit analysis, digital logic, electronics, programming, computer-aided design, solid and fluid mechanics, chemistry, dynamic systems and controls, and mathematics are considered. Questions ask participants to rank the priority or importance of potential core concepts from these categories and also provide opportunities for open-ended response. The results of this survey identify gaps between existing undergraduate curricula, student experience, and employer expectations, and continuing work will provide insight into the direction of a unifying curricular design for MRE education. 

Whereas vision dominates sensing in robots, animals with limited vision deftly navigate their environment using other forms of perception, such as touch. Efforts have been made to apply artificial skins with tactile sensing to robots for similarly sophisticated mobile and manipulative skills. The ability to functionally mimic the afferent sensory neural network, required for distributed sensing and communication networks throughout the body, is still missing. This limitation is partially due to the lack of cointegration of the mechanosensors in the body of the robot. Here, lacings of stretchable optical fibers distributed throughout 3D-printed elastomer frameworks created a cointegrated body, sensing, and communication network. This soft, functional structure could localize deformation with submillimeter positional accuracy (error of 0.71 millimeter) and sub-Newton force resolution (~0.3 newton).