scholarly journals An Ultrastretchable Electrical Switch Fiber with a Magnetic Liquid Metal Core for Remote Magnetic Actuation

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2407
Author(s):  
Kyeongmin Hong ◽  
Minjae Choe ◽  
Seoyeon Kim ◽  
Hye-Min Lee ◽  
Byung-Joo Kim ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Ambient Pressure ◽  
Elastic Fiber ◽  
Iron Particle ◽  
Elastic Fibers ◽  
Magnetic Actuation ◽  
Magnetic Liquid ◽  
The Core ◽  
Conformal Electronics ◽  
Magnetic Strength

In this work we describe a soft and ultrastretchable fiber with a magnetic liquid metal (MLM) core for electrical switches used in remote magnetic actuation. MLM was prepared by removing the oxide layer on the liquid metal and subsequent mixing with magnetic iron particles. We used SEBS (poly[styrene-b-(ethylene-co-butylene)-b-styrene]) and silicone to prepare stretchable elastic fibers. Once hollow elastic fibers form, MLM was injected into the core of the fiber at ambient pressure. The fibers are soft (Young’s modulus of 1.6~4.4 MPa) and ultrastretchable (elongation at break of 600~5000%) while maintaining electrical conductivity and magnetic property due to the fluidic nature of the core. Magnetic strength of the fibers was characterized by measuring the maximum effective distance between the magnet and the fiber as a function of iron particle concentration in the MLM core and the polymeric shell. The MLM core facilitates the use of the fiber in electrical switches for remote magnetic actuation. This ultrastretchable and elastic fiber with MLM core can be used in soft robotics, and wearable and conformal electronics.

scholarly journals Enhancement of elastin expression by transdermal administration of sialidase isozyme Neu2

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Akira Minami ◽  
Yuka Fujita ◽  
Jun Goto ◽  
Ayano Iuchi ◽  
Kosei Fujita ◽  
...  
Keyword(s):  
Sialic Acid ◽  
Skin Diseases ◽  
Lower Layer ◽  
Elastic Fiber ◽  
Sialic Acid Residue ◽  
Elastic Fibers ◽  
Transdermal Administration ◽  
Sialidase Activity ◽  
Fiber Assembly ◽  
Senescence Accelerated Mice

AbstractReduction of elastin in the skin causes various skin diseases as well as wrinkles and sagging with aging. Sialidase is a hydrolase that cleaves a sialic acid residue from sialoglycoconjugate. Cleavage of sialic acid from microfibrils by the sialidase isozyme Neu1 facilitates elastic fiber assembly. In the present study, we showed that a lower layer of the dermis and muscle showed relatively intense sialidase activity. The sialidase activity in the skin decreased with aging. Choline and geranate (CAGE), one of the ionic liquids, can deliver the sialidase subcutaneously while maintaining the enzymatic activity. The elastin level in the dermis was increased by applying sialidase from Arthrobacter ureafaciens (AUSA) with CAGE on the skin for 5 days in rats and senescence-accelerated mice prone 1 and 8. Sialidase activity in the dermis was considered to be mainly due to Neu2 based on the expression level of sialidase isozyme mRNA. Transdermal administration of Neu2 with CAGE also increased the level of elastin in the dermis. Therefore, not only Neu1 but also Neu2 would be involved in elastic fiber assembly. Transdermal administration of sialidase is expected to be useful for improvement of wrinkles and skin disorders due to the loss of elastic fibers.

scholarly journals Clinical Relevance of Elastin in the Structure and Function of Skin

2021 ◽  
Author(s):  
Leslie Baumann ◽  
Eric F Bernstein ◽  
Anthony S Weiss ◽  
Damien Bates ◽  
Shannon Humphrey ◽  
...  
Keyword(s):  
Wound Healing ◽  
Clinical Relevance ◽  
Structural Integrity ◽  
Elastic Fiber ◽  
Subcutaneous Fat ◽  
Structure And Function ◽  
Fiber Formation ◽  
Elastic Fibers ◽  
Superficial Dermis ◽  
And Function

Abstract Elastin is the main component of elastic fibers, which provide stretch, recoil, and elasticity to the skin. Normal levels of elastic fiber production, organization, and integration with other cutaneous extracellular matrix proteins, proteoglycans, and glycosaminoglycans are integral to maintaining healthy skin structure, function, and youthful appearance. Although elastin has very low turnover, its production decreases after individuals reach maturity and it is susceptible to damage from many factors. With advancing age and exposure to environmental insults, elastic fibers degrade. This degradation contributes to the loss of the skin’s structural integrity; combined with subcutaneous fat loss, this results in looser, sagging skin, causing undesirable changes in appearance. The most dramatic changes occur in chronically sun-exposed skin, which displays sharply altered amounts and arrangements of cutaneous elastic fibers, decreased fine elastic fibers in the superficial dermis connecting to the epidermis, and replacement of the normal collagen-rich superficial dermis with abnormal clumps of solar elastosis material. Disruption of elastic fiber networks also leads to undesirable characteristics in wound healing, and the worsening structure and appearance of scars and stretch marks. Identifying ways to replenish elastin and elastic fibers should improve the skin’s appearance, texture, resiliency, and wound-healing capabilities. However, few therapies are capable of repairing elastic fibers or substantially reorganizing the elastin/microfibril network. This review describes the clinical relevance of elastin in the context of the structure and function of healthy and aging skin, wound healing, and scars and introduces new approaches being developed to target elastin production and elastic fiber formation.

scholarly journals Dill Extract Induces Elastic Fiber Neosynthesis and Functional Improvement in the Ascending Aorta of Aged Mice with Reversal of Age-Dependent Cardiac Hypertrophy and Involvement of Lysyl Oxidase-Like-1

Biomolecules ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 173 ◽  
Author(s):  
Wassim Fhayli ◽  
Quentin Boëté ◽  
Nadjib Kihal ◽  
Valérie Cenizo ◽  
Pascal Sommer ◽  
...  
Keyword(s):  
Cardiac Hypertrophy ◽  
Lysyl Oxidase ◽  
Elastic Fiber ◽  
Ascending Aorta ◽  
Functional Improvement ◽  
Elastic Fibers ◽  
Aged Mice ◽  
Age Related ◽  
And Function

Elastic fibers (90% elastin, 10% fibrillin-rich microfibrils) are synthesized only in early life and adolescence mainly by the vascular smooth muscle cells through the cross-linking of its soluble precursor, tropoelastin. Elastic fibers endow the large elastic arteries with resilience and elasticity. Normal vascular aging is associated with arterial remodeling and stiffening, especially due to the end of production and degradation of elastic fibers, leading to altered cardiovascular function. Several pharmacological treatments stimulate the production of elastin and elastic fibers. In particular, dill extract (DE) has been demonstrated to stimulate elastin production in vitro in dermal equivalent models and in skin fibroblasts to increase lysyl oxidase–like-1 (LOXL-1) gene expression, an enzyme contributing to tropoelastin crosslinking and elastin formation. Here, we have investigated the effects of a chronic treatment (three months) of aged male mice with DE (5% or 10% v/v, in drinking water) on the structure and function of the ascending aorta. DE treatment, especially at 10%, of aged mice protected pre-existing elastic lamellae, reactivated tropoelastin and LOXL-1 expressions, induced elastic fiber neo-synthesis, and decreased the stiffness of the aging aortic wall, probably explaining the reversal of the age-related cardiac hypertrophy also observed following the treatment. DE could thus be considered as an anti-aging product for the cardiovascular system.

scholarly journals Collagen and Elastic Fiber Content Correlation Analysis between Horizontal and Vertical Orientations of Skin Samples of Human Body

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Naveen Kumar ◽  
Pramod Kumar ◽  
Satheesha Nayak Badagabettu ◽  
Ranjini Kudva ◽  
Sudarshan Surendran ◽  
...  
Keyword(s):  
Abdominal Wall ◽  
Negative Correlation ◽  
Anterior Abdominal Wall ◽  
Elastic Fiber ◽  
Elastic Fibers ◽  
Correlation Pattern ◽  
Unequal Distribution ◽  
Dermal Collagen ◽  
Lateral Chest ◽  
Skin Samples

Background. Unequal distribution of dermal collagen and elastic fibers in different orientations of skin is reported to be one of the multifocal causes of scar related complications. Present study is to understand the correlation pattern between collagen in horizontal (CH) and in vertical (CV) directions as well as that of elastic in horizontal (EH) and vertical (EV) directions.Materials and Method. A total of 320 skin samples were collected in two orientations from suprascapular, anterior chest, lateral chest, anterior abdominal wall, and inguinal regions of 32 human cadavers. Spearman correlation coefficient (r) was calculated between the variables (CH,CV,EH, andEV).Results. Significant positive correlation betweenCHandCV, and betweenEHandEVobserved in all 5 areas tested. A negative correlation betweenCVandEVat suprascapular, lateral chest, and inguinal regions and negative correlation betweenCHandEHat anterior chest and anterior abdominal wall have been identified.Conclusion. Knowledge of asymmetric content of dermal collagen and elastic fibers together with the varied strength and degree of association in the given area provides guidelines to the dermatologists and aesthetic surgeons in placing elective incisions in the direction maximally utilizing the anatomical facts for aesthetically pleasing result.

Stiffness-Tunable and all-soft electrical smart material made by magnetic liquid metal and sponge

2021 ◽  
Author(s):  
K. Wang ◽  
J. Zhou ◽  
S. Li ◽  
J. Hu ◽  
J. Yang ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Smart Material ◽  
Magnetic Liquid

scholarly journals Guiding magnetic liquid metal for flexible circuit

2021 ◽  
Author(s):  
Chengjun Zhang ◽  
Qing Yang ◽  
Jiale Yong ◽  
Chao Shan ◽  
Jingzhou Zhang ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Magnetic Liquid

Elastin exhibits a distinctive temporal and spatial pattern of distribution in the developing chick limb in association with the establishment of the cartilaginous skeleton

1994 ◽  
Vol 107 (9) ◽  
pp. 2623-2634 ◽  
Author(s):  
J.M. Hurle ◽  
G. Corson ◽  
K. Daniels ◽  
R.S. Reiter ◽  
L.Y. Sakai ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Spatial Pattern ◽  
Elastic Fiber ◽  
Spatial Location ◽  
Limb Bud ◽  
Confocal Laser ◽  
Elastic Fibers ◽  
Type I ◽  
Temporal And Spatial

In this work we have analyzed the presence of elastic components in the extracellular matrices of the developing chick leg bud. The distributions of elastin and fibrillin were studied immunohistochemically in whole-mount preparations using confocal laser microscopy. The association of these constituents of the elastic matrix with other components of the extracellular matrix was also studied, using several additional antibodies. Our results reveal the transient presence of an elastin-rich scaffold of extracellular matrix fibrillar material in association with the establishment of the cartilaginous skeleton of the leg bud. The scaffold consisted of elastin-positive fibers extending from the ectodermal surface of the limb to the central cartilage-forming regions and between adjacent cartilages. Fibrillin immunolabeling was negative in this fibrillar scaffold while other components of the extracellular matrix including: tenascin, laminin and collagens type I, type III and type VI; appeared codistributed with elastin in some regions of the scaffold. Progressive changes in the spatial pattern of distribution of the elastin-positive scaffold were detected in explant cultures in which one expects a modification in the mechanical stresses of the tissues related to growth. A scaffold of elastin comparable to that found in vivo was also observed in high-density micromass cultures of isolated limb mesodermal cells. In this case the elastic fibers are observed filling the spaces located between the cartilaginous nodules. The fibers become reoriented and attach to the ectodermal basal surface when an ectodermal fragment is located at the top of the growing micromass. Our results suggest that the formation of the cartilaginous skeleton of the limb involves the segregation of the undifferentiated limb mesenchyme into chondrogenic and elastogenic cell lineages. Further, a role for the elastic fiber scaffold in coordinating the size and the spatial location of the cartilaginous skeletal elements within the limb bud is also suggested from our observations.

Behavior of Inert Gas Bubbles in Forced Convective Liquid Metal Circuits

1976 ◽  
Vol 98 (1) ◽  
pp. 5-11 ◽  
Author(s):  
W. J. Minkowycz ◽  
D. M. France ◽  
R. M. Singer
Keyword(s):  
Liquid Metal ◽  
Bubble Dynamics ◽  
Bubble Radius ◽  
Gas Bubbles ◽  
Inert Gas ◽  
Liquid Sodium ◽  
Gas Bubble ◽  
Flowing Liquid ◽  
Argon Gas ◽  
The Core

Conservation equations are derived for the motion of a small inert gas bubble in a large flowing liquid-gas solution subjected to large thermal gradients. Terms which are of the second order of magnitude under less severe and steady-state conditions are retained, thus resulting in an expanded form of the Rayleigh equation. The bubble dynamics is a function of opposing mechanisms tending to increase or decrease bubble volume while being transported with the solution. Diffusion of inert gas between the bubble and the solution is one of the most important of these mechanisms included in the analysis. The analytical model is applied to an argon gas bubble flowing in a weak solution of argon gas in liquid sodium. Calculations are performed for these fluids under conditions typical of normal and abnormal operation of a liquid metal fast breeder reactor (LMFBR) core and the resulting bubble radius, internal gas pressure, and mass of inert gas are presented in each case. An important result obtained indicates that inert gas bubbles reaching the core inlet of an LMFBR will always grow as they traverse the core under normal and extreme abnormal conditions and that the rate of growth is quite small in all cases.

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