Comparative Immunology
Julius P. Kreier in Infection, Resistance, and Immunity, 2022
Invertebrates protect themselves against invasion by processes of phagocytosis, humoral immunity, and cell-mediated immunity as well as by physical barriers. For example, arthropods have tough exoskeletons made of chitin that can protect them against all types of attackers. The horseshoe crab (Limulus polyphemus) not only has a hard exoskeleton but can also protect itself against bacterial endotoxins by secreting a specialized glycoprotein through pores in the carapace. On contact with bacterial endotoxins, this glycoprotein coagulates, sealing the pores and immobilizing any invading bacteria. Other invertebrates such as the coelenterates, annelids, mollusca, and echinoderms may secrete masses of sticky antibacterial mucus when attacked thereby immobilizing potential invaders.
Digital Health Technology for Behavior Change
James M. Rippe in Lifestyle Medicine, 2019
To date, the use of advanced exoskeletons has largely been limited to patients with paraplegia or other severe neurological disorders, and to specialized military or industrial applications. While the technology has proven valuable for rehabilitation and limited functional ambulation, it has faced many barriers to adoption, including high cost, heavy components, and difficulty donning and doffing.191 However, new types of exoskeletons and exosuits that use soft materials, such as fabrics, and alternative actuator systems, such as air compression, are significantly lighter, easier to use, more adaptable to body differences, and less expensive.192,193 While the technology is only starting to be assessed in the literature,194–196 it has potential to be widely integrated into daily life. People with less severe limitations than paraplegia, such as the elderly, those with joint pains or muscle weakness,197,198 or even healthy users, could wear these devices to assist with daily activity. The technologies could be incorporated into clothing, braces, or shoes to enable easier ambulation, running, hiking,199 jumping, or other physical activities.
Exoskeleton: The New Horizon of Robotic Assistance for Human Gait
Stefano Federici, Marcia J. Scherer in Assistive Technology Assessment Handbook, 2017
An exoskeleton is an active mechanical device that is anthropomorphic in nature, is “worn” by an operator, fits closely to his or her body, and works in concert with the wearer's movements. Generally, the term “exoskeleton” is used to describe a device augmenting the performance of an able-bodied wearer. In contrast, the term “active orthosis” is described as a device that is used to increase the ambulatory ability of a person with disability, for example, someone suffering from a leg pathology. Occasionally, however, the term “exoskeleton” is also used to describe certain assistive devices that enclose the majority of the lower limbs (Dollar and Herr, 2008).
Finite element analysis of lower limb exoskeleton during sit-to-stand transition
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2021
Umesh K., Vidhyapriya R.
Artificial lower limb exoskeleton is a device used to assist the locomotion of an individual. Such devices are employed either to assist person for rehabilitation after a disability or to assist soldiers in bearing the load during combat operations. In either way, an exoskeleton is a wearable system that can house the lower limbs and provided with the facility to move along with the natural movement of a person. Such devices cannot be manufacture under mass production, since every individual has the unique gait pattern and dimensions. Gait analysis is always encouraged for interpreting the data requirements in the individualization of devices. An exoskeleton consists of structural components to hold the body segments for bearing the body weight, several actuator systems for joint movements, and control circuitry for control of movements, balance, and gait generation (Kim et al. 2013; Liu et al. 2012; Mooney et al. 2014). Several techniques are employed for controlling an exoskeleton, which includes joystick, EMG, EEG, voice assist, etc. The controlling techniques of exoskeleton are selected based on the ability of the patients (Shaari et al. 2015; Wicaksono et al. 2016; Zhu et al. 2015). The users of the exoskeleton will be patients who have limbs but they lost the ability to support the entire weight of the body.
A quick and versatile protocol for the 3D visualization of transgene expression across the whole body of larval Drosophila
Published in Journal of Neurogenetics, 2021
Oliver Kobler, Aliće Weiglein, Kathrin Hartung, Yi-chun Chen, Bertram Gerber, Ulrich Thomas
Pioneered by Werner Spalteholz a century ago, tissue clearing proved to be a groundbreaking technique in microscopic anatomy (Eisenstein, 2018; Spalteholz, 1911) once optimized protocols were combined with state-of-the-art cell labeling, microscopy, and image data processing (Ueda et al., 2020). This paved the way for striking insights into the morphology and cytoarchitecture of relatively large, intact, and complete organs, including mammalian brains and indeed their neuronal projections throughout the body (Cai et al., 2019). Given that these approaches work for animals the size of a mouse and ‘through skin and bone’, it might have seemed trivial to apply them to much smaller animals such as Drosophila, too. The cuticular exoskeleton of arthropods, however, proves to be a tricky obstacle to clearing. A recent protocol (Pende et al., 2018) has addressed this problem with remarkable success and was documented and optimized for pupal and adult stages.
Design recommendations for exoskeletons: Perspectives of individuals with spinal cord injury
Published in The Journal of Spinal Cord Medicine, 2023
Lysanne van Silfhout, Allard J.F. Hosman, Henk van de Meent, Ronald H.M.A. Bartels, Michael J.R. Edwards
More than 50% of the participants thought they would not need crutches while walking with an exoskeleton. However, most of the current exoskeletons are not designed to maintain balance, which is the reason that the patient needs crutches during ambulation. An exception to this is the REX exoskeleton by REX Bionics.22 This is also the reason that exoskeletons are currently unsuitable for users with higher-level SCI, who have poor upper extremity strength. Moreover, the ambulatory speed of current exoskeletons is relatively low, on average 0.26 m/s.11 Despite that, over 10% of the participants in this study expected that one can ambulate with an exoskeleton just as fast or even faster than able-bodied people. However, the average walking speed of able-bodied people is far higher, namely 1.3–1.4 m/s.23
Related Knowledge Centers
- Animal
- Chitin
- Desiccation
- Endoskeleton
- Muscle
- Skeleton
- Soft Tissue
- Armour
- Arthropod Exoskeleton
- Mollusc Shell