Note on Heat Effects in Capillary Flow

© 2020, The Author(s), under exclusive licence to Springer Nature Limited. Understanding ethnic differences in pain is important for addressing disparities in pain care. A common belief is that African Americans are hyposensitive to pain compared to Whites, but African Americans show increased pain sensitivity in clinical and laboratory settings. The neurobiological mechanisms underlying these differences are unknown. We studied an ethnicity- and gender-balanced sample of African Americans, Hispanics and non-Hispanic Whites using functional magnetic resonance imaging during thermal pain. Higher pain report in African Americans was mediated by discrimination and increased frontostriatal circuit activations associated with pain rating, discrimination, experimenter trust and extranociceptive aspects of pain elsewhere. In contrast, the neurologic pain signature, a neuromarker sensitive and specific to nociceptive pain, mediated painful heat effects on pain report largely similarly in African American and other groups. Findings identify a brain basis for higher pain in African Americans related to interpersonal context and extranociceptive central pain mechanisms and suggest that nociceptive pain processing may be similar across ethnicities.

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Capillary flows and self-assembly of porous hydrate structures

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2012.1.003 ◽

2012 ◽

Vol 9 (1) ◽

pp. 22-25

Author(s):

S.V. Amel’kin ◽

D.Ye. Igoshin

Keyword(s):

Experimental Data ◽

Aqueous Solution ◽

Self Assembly ◽

Capillary Flow ◽

Secondary Crystallization ◽

Assembly Model ◽

Physical Processes ◽

Good Correspondence ◽

Solution Formation ◽

Capillary Flows

A self-assembly model for porous hydrate structures is proposed, which takes into account the sequence of basic physical processes: hydrate growth on the surface of the aqueous solution, formation of islet structure, capillary flow, separation and transfer of secondary crystallization nuclei to the meniscus. The model was studied within the cellular automata method. A good correspondence between the results of the simulation and the experimental data is obtained.

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CAPILLARY FLOW OF FLOW IN SEDIMENTARY BASINS

10.1130/abs/2020am-354567 ◽

2020 ◽

Author(s):

Lawrence Cathles ◽

Keyword(s):

Capillary Flow ◽

Sedimentary Basins

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Rapid synchronized fabrication of vascularized thermosets and composites

Nature Communications ◽

10.1038/s41467-021-23054-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Mayank Garg ◽

Jia En Aw ◽

Xiang Zhang ◽

Polette J. Centellas ◽

Leon M. Dean ◽

...

Keyword(s):

Large Scale ◽

Capillary Flow ◽

External Heat ◽

Frontal Polymerization ◽

Self Healing ◽

Vascular Networks ◽

Ambient Conditions ◽

External Energy ◽

Imaging Phantoms ◽

Vascular Structures

AbstractBioinspired vascular networks transport heat and mass in hydrogels, microfluidic devices, self-healing and self-cooling structures, filters, and flow batteries. Lengthy, multistep fabrication processes involving solvents, external heat, and vacuum hinder large-scale application of vascular networks in structural materials. Here, we report the rapid (seconds to minutes), scalable, and synchronized fabrication of vascular thermosets and fiber-reinforced composites under ambient conditions. The exothermic frontal polymerization (FP) of a liquid or gelled resin facilitates coordinated depolymerization of an embedded sacrificial template to create host structures with high-fidelity interconnected microchannels. The chemical energy released during matrix polymerization eliminates the need for a sustained external heat source and greatly reduces external energy consumption for processing. Programming the rate of depolymerization of the sacrificial thermoplastic to match the kinetics of FP has the potential to significantly expedite the fabrication of vascular structures with extended lifetimes, microreactors, and imaging phantoms for understanding capillary flow in biological systems.

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Thin-Film Processing of Polypropylene and Polystyrene Sheets by a Continuous Wave CO2 Laser with the Cu Cooling Base

Polymers ◽

10.3390/polym13091448 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1448

Author(s):

Nobukazu Kameyama ◽

Hiroki Yoshida ◽

Hitoshi Fukagawa ◽

Kotaro Yamada ◽

Mitsutaka Fukuda

Keyword(s):

Thin Film ◽

Co2 Laser ◽

Continuous Wave ◽

Cw Laser ◽

Heat Effects ◽

Film Processing ◽

Carbon Dioxide Co2 ◽

A Minor ◽

Residual Heat ◽

Thin Film Processing

Carbon dioxide (CO2) laser is widely used in commercial and industrial fields to process various materials including polymers, most of which have high absorptivity in infrared spectrum. Thin-film processing by the continuous wave (CW) laser is difficult since polymers are deformed and damaged by the residual heat. We developed the new method to make polypropylene (PP) and polystyrene (PS) sheets thin. The sheets are pressed to a Cu base by extracting air between the sheets and the base during laser processing. It realizes to cut the sheets to around 50 µm thick with less heat effects on the backside which are inevitable for thermal processing using the CW laser. It is considered that the boundary between the sheets and the base is in thermal equilibrium and the base prevents the sheets from deforming to support the backside. The method is applicable to practical use since it does not need any complex controls and is easy to install to an existing equipment with a minor change of the stage.

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