scholarly journals Platinized graphene fiber electrodes uncover direct spleen-vagus communication

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Maria A. Gonzalez-Gonzalez ◽  
Geetanjali S. Bendale ◽  
Kezhong Wang ◽  
Gordon G. Wallace ◽  
Mario Romero-Ortega
Keyword(s):  
High Performance ◽  
Liquid Crystalline ◽  
Anatomical Location ◽  
Tract Tracing ◽  
Pharmacological Modulation ◽  
Significant Challenge ◽  
Point Of Entry ◽  
Neural Modulation ◽  
Major Organ ◽  
Stimulation Of

AbstractNeural interfacing nerve fascicles along the splenic neurovascular plexus (SNVP) is needed to better understand the spleen physiology, and for selective neuromodulation of this major organ. However, their small size and anatomical location have proven to be a significant challenge. Here, we use a reduced liquid crystalline graphene oxide (rGO) fiber coated with platinum (Pt) as a super-flexible suture-like electrode to interface multiple SNVP. The Pt-rGO fibers work as a handover knot electrodes over the small SNVP, allowing sensitive recording from four splenic nerve terminal branches (SN 1–4), to uncover differential activity and axon composition among them. Here, the asymmetric defasciculation of the SN branches is revealed by electron microscopy, and the functional compartmentalization in spleen innervation is evidenced in response to hypoxia and pharmacological modulation of mean arterial pressure. We demonstrate that electrical stimulation of cervical and sub-diaphragmatic vagus nerve (VN), evokes activity in a subset of SN terminal branches, providing evidence for a direct VN control over the spleen. This notion is supported by adenoviral tract-tracing of SN branches, revealing an unconventional direct brain-spleen projection. High-performance Pt-rGO fiber electrodes, may be used for the fine neural modulation of other small neurovascular plexus at the point of entry of major organs as a bioelectronic medical alternative.

scholarly journals Platinized graphene fiber electrodes revealed differential activity in terminal splenic neurovascular plexi supporting a direct spleen-vagus communication

2021 ◽  
Author(s):  
María A. González-González ◽  
Geetanjali Bendale ◽  
K Wang ◽  
Gordon G. Wallace ◽  
Mario Romero-Ortega
Keyword(s):  
High Performance ◽  
Liquid Crystalline ◽  
Anatomical Location ◽  
Tract Tracing ◽  
Pharmacological Modulation ◽  
Significant Challenge ◽  
Point Of Entry ◽  
Neural Modulation ◽  
Major Organ ◽  
Stimulation Of

AbstractNeural interfacing nerve fascicles along the splenic neurovascular plexi (SNVP) is needed to better understand the spleen physiology, and for selective neuromodulation of this major organ. However, the small size and anatomical location have proven to be a significant challenge. Here, we use a reduced liquid crystalline graphene oxide (rGO) fiber coated with platinum (Pt) as a super-flexible suture-like electrode to interface multiple SNVP. The Pt-rGO fibers were used as handover knot electrodes over the small plexi, allowing sensitive recording from the splenic nerve (SN) terminal branches. Asymmetric defasciculation of the SN branches was revealed by electron microscopy, and the functional compartmentalization in spleen innervation was evidenced in response to hypoxia and pharmacological modulation of mean arterial pressure. We demonstrate that electrical stimulation of cervical and subdiaphragmatic vagus nerve (VN), evoked direct activity in a subset of SN terminal branches, providing evidence for a direct VN control over the spleen. This notion was supported by tract-tracing of SN branches, revealing an unconventional direct spleen-VN projection. High-performance Pt-rGO fiber electrodes, may be used for the fine neural modulation of other small neurovascular plexi at the point of entry of the organs as a bioelectronic medical alternative.

Morphology of High-Performance Rigid-Rod Polymer Fibers and Molecular Composites

1989 ◽  
Vol 47 ◽  
pp. 338-339
Author(s):  
W.W. Adams ◽  
S. J. Krause
Keyword(s):  
Tensile Strength ◽  
High Performance ◽  
Liquid Crystalline ◽  
Molecular Level ◽  
Synergistic Effects ◽  
Tensile Modulus ◽  
Commercial Development ◽  
The Matrix ◽  
Molecular Composites ◽  
Rigid Rod

Rigid-rod polymers such as PBO, poly(paraphenylene benzobisoxazole), Figure 1a, are now in commercial development for use as high-performance fibers and for reinforcement at the molecular level in molecular composites. Spinning of liquid crystalline polyphosphoric acid solutions of PBO, followed by washing, drying, and tension heat treatment produces fibers which have the following properties: density of 1.59 g/cm3; tensile strength of 820 kpsi; tensile modulus of 52 Mpsi; compressive strength of 50 kpsi; they are electrically insulating; they do not absorb moisture; and they are insensitive to radiation, including ultraviolet. Since the chain modulus of PBO is estimated to be 730 GPa, the high stiffness also affords the opportunity to reinforce a flexible coil polymer at the molecular level, in analogy to a chopped fiber reinforced composite. The objectives of the molecular composite concept are to eliminate the thermal expansion coefficient mismatch between the fiber and the matrix, as occurs in conventional composites, to eliminate the interface between the fiber and the matrix, and, hopefully, to obtain synergistic effects from the exceptional stiffness of the rigid-rod molecule. These expectations have been confirmed in the case of blending rigid-rod PBZT, poly(paraphenylene benzobisthiazole), Figure 1b, with stiff-chain ABPBI, poly 2,5(6) benzimidazole, Fig. 1c A film with 30% PBZT/70% ABPBI had tensile strength 190 kpsi and tensile modulus of 13 Mpsi when solution spun from a 3% methane sulfonic acid solution into a film. The modulus, as predicted by rule of mixtures, for a film with this composition and with planar isotropic orientation, should be 16 Mpsi. The experimental value is 80% of the theoretical value indicating that the concept of a molecular composite is valid.

The Influence of Recycling On Thermotropic Liquid Crystalline Polymer and Glass Fiber Composites

2021 ◽  
Author(s):  
Tianran Chen
Keyword(s):  
High Performance ◽  
Liquid Crystalline ◽  
Tensile Modulus ◽  
Crystalline Polymer ◽  
Fiber Composites ◽  
Reinforced Composites ◽  
Recycling Process ◽  
Mechanical Recycling ◽  
Glass Fiber Composites ◽  
Pp Composites

In this paper, high-performance thermotropic liquidcrystalline polymer (TLCP)/polypropylene (PP) and glassfiber (GF)/PP composites were prepared by the injectionmolding process. Mechanical recycling of TLCP/PP andGF/PP composites consisted of grinding of the injectionmolded specimens and further injection molding of thegranules. The influence of mechanical recycling onmechanical and thermal properties was investigated. In situTLCP/PP maintains tensile modulus and strength duringthe recycling process, indicating the regeneration ofpolymeric fibrils at each reprocessing stage. GF/PPcomposite exhibits deterioration of mechanical propertiesafter recycling because of fiber breakage during processing,which is a very common issue on reusing glass or carbonfiber reinforced composites. The experimental resultsreveal that the TLCP/PP composite has better recyclabilitythan GF/PP.

High Performance Capacitors Using BaTiO3 Nanowires Engineered by Rigid Liquid-crystalline Polymers

2017 ◽  
Vol 121 (37) ◽  
pp. 20075-20083 ◽  
Author(s):  
Dou Zhang ◽  
Chao Ma ◽  
Xuefan Zhou ◽  
Sheng Chen ◽  
Hang Luo ◽  
...  
Keyword(s):  
High Performance ◽  
Liquid Crystalline ◽  
Liquid Crystalline Polymers ◽  
Crystalline Polymers

Theoretical Studies of the Physical Properties of Rodlike and Related Polymers

1988 ◽  
Vol 134 ◽  
Author(s):  
W. J. Welsh ◽  
J. E. Mark ◽  
Y. Yang ◽  
G. P. Das
Keyword(s):  
High Performance ◽  
Liquid Crystalline ◽  
Theoretical Work ◽  
Environmental Resistance ◽  
New Class ◽  
Protonated Forms ◽  
New Type ◽  
Electrooptical Properties ◽  
Cis And Trans ◽  
Strong Acids

ABSTRACTThis review focuses on a new type of para-catenated aromatic polymer being used in the preparation of high-performance films and fibers of exceptional strength, thermal stability, and environmental resistance, including inertness to essentially all common solvents. Polymers of this type include the cis- and trans-poly(p-phenylene benzobisoxazole) (PBO), the cis- and trans-forms of the corresponding poly(pphenylene benzobisthiazole) (PBT), and the structurally similar poly(5,5ʹ-bibenzoxazole-2.2ʹ-diyl-l,3-phenylene) (AAPBO) and poly(2,5-benzoxazole) (ABPBO) and their sulfurcontaining analogues. Because of their rigidity, these polymers become highly oriented in solution and some display liquid crystalline behavior. The purpose of this paper is to summarize the authorsʹ theoretical work on the structures, conformational energies, intermolecular interactions, electronic properties, electrical conductivity, and electrooptical properties of these chains, including, in some cases, the so-called articulated forms and the protonated forms known to exist in strong acids. The emphasis is on how such studies provide a molecular understanding of the unusual properties and processing characteristics of this new class of materials.

High performance liquid crystalline physical gels prepared by side chain liquid crystalline polymers

Polymer ◽  
2018 ◽  
Vol 151 ◽  
pp. 75-83 ◽  
Author(s):  
Jianhang Zhao ◽  
Yongjie Yuan ◽  
Lei Chen ◽  
Ye Li ◽  
Hailiang Zhang
Keyword(s):  
High Performance ◽  
Liquid Crystalline ◽  
Liquid Crystalline Polymers ◽  
Side Chain ◽  
Crystalline Polymers

Graphene-Ta2O5 Heterostructure Enabled High Performance, Deep-Ultraviolet to Mid-Infrared Photodetection

Nanoscale ◽  
2021 ◽  
Author(s):  
Vinh Ho ◽  
Yifei Wang ◽  
Michael Cooney ◽  
Nguyen Q Vinh
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Low Cost ◽  
Infrared Region ◽  
Temperature Sensitive ◽  
Mid Infrared ◽  
Significant Challenge ◽  
Deep Ultraviolet ◽  
Infrared Photodetection

Ultrafast, high sensitive, low cost photodetectors operating at room temperature sensitive from the deep-ultraviolet to mid-infrared region remain a significant challenge in optoelectronics. Achievements in traditional semiconductors using cryogenic operation...

CAP2b, a cardioacceleratory peptide, is present in Drosophila and stimulates tubule fluid secretion via cGMP

1995 ◽  
Vol 269 (6) ◽  
pp. R1321-R1326 ◽  
Author(s):  
S. A. Davies ◽  
G. R. Huesmann ◽  
S. H. Maddrell ◽  
M. J. O'Donnell ◽  
N. J. Skaer ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Manduca Sexta ◽  
High Performance ◽  
Fluid Secretion ◽  
Malpighian Tubules ◽  
Cyclic Monophosphate ◽  
Cgmp Signaling ◽  
Camp And Cgmp ◽  
Tubule Fluid ◽  
Stimulation Of

A cardioacceleratory peptide, CAP2b, identified originally in the lepidopteran Manduca sexta, stimulates fluid secretion by Malpighian tubules of the dipteran Drosophila melanogaster. High-performance liquid chromatography analyses of adult D. melanogaster reveal the presence of a CAP2b-like peptide, that coelutes with M. sexta CAP2b and synthetic CAP2b and that has CAP2b-like effects on the M. sexta heart. CAP2b accelerates fluid secretion in tubules stimulated by adenosine 3',5'-cyclic monophosphate (cAMP) but has no effect on tubules stimulated by guanosine 3',5'-cyclic monophosphate (cGMP), implying that it acts through the latter pathway. By contrast, the action of leucokinin is additive to both cAMP and cGMP but not to thapsigargin, suggesting that leucokinin acts by the elevation of intracellular calcium. CAP2b stimulation elevates tubule cGMP levels but not those of cAMP. By contrast, leucokinin has no effect on levels of either cyclic nucleotide. Both CAP2b and cGMP increase transepithelial potential difference, suggesting that stimulation of vacuolar-adenosinetriphosphatase action underlies the corresponding increases in fluid secretion. Overall, the results show that a Drosophila CAP2b-related peptide acts to stimulate fluid secretion by Malpighian tubules through the cGMP-signaling pathway.

Sign in / Sign up

Export Citation Format

Share Document