Enhanced cooling methods are needed for advanced power systems. A promising method is using an open-cell metal foam to improve the heat transfer rates. However, the pressure drop induced by the metal ...foams is relatively higher and thus becomes a critical issue in engineering applications. The focus of this research is the modeling and simulation of heat transfer enhancement and corresponding pressure drop.
A simplified analytical model based on diamond-shaped unit cells has been developed to predict the heat transfer capability of a foamed channel. The heat transfer rates predicted by the analytical model have been compared with available experimental data from other researchers and favorable agreements have been obtained. To evaluate the pressure drop in metal foams, a unit-cell CFD model was built using software package Fluent. The model is based on a structure of sphere-centered open-cell tetrakaidecahedron, which is very similar to the actual microstructure of an aluminum metal foam. Flow patterns and grid independence are investigated and simulation results are shown to agree well with experimental data.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Phytochemicals have been used as potential chemopreventive or chemotherapeutic agents. However, there are data suggesting a mutagenic effect of some phytochemicals. We hypothesized that safrole would ...have anticancer effects on human oral squamous cell carcinoma HSC-3 cells. Safrole decreased the percentage of viable HSC-3 cells via induction of apoptosis by an increased level of cytosolic Ca2+ and a reduction in the mitochondrial membrane potential (ΔΨ
m
). Changes in the membrane potential were associated with changes in the Bax, release of cytochrome c from mitochondria, and activation of downstream caspases-9 and -3, resulting in apoptotic cell death. In vivo studies also showed that safrole reduced the size and volume of an HSC-3 solid tumor on a xenograft athymic nu/nu mouse model. Western blotting and flow cytometric analysis studies confirmed that safrole-mediated apoptotic cell death of HSC-3 cells is regulated by cytosolic Ca2+ and by mitochondria- and Fas-dependent pathways.
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CMK, NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
A novel disposable transnasal esophagoscope, the E.G. Scan (IntroMedic Co. Ltd., Seoul, Korea), was developed for the evaluation of esophageal diseases while eliminating the inconvenience associated ...with sterilization, portability, patient monitoring, complications, and the economic burden of sedation. The feasibility, safety, and tolerability of the first version of the E.G. Scan was evaluated in this pilot study. Nasal esophagoscopy was performed successfully in 46 patients with known or suspected esophageal diseases. At least 50% of the Z-line was visualized by the E.G. Scan in 38 (82.6%) of 46 patients. Abnormalities were identified in 27 patients: erosive esophagitis (n=18), Barrett's esophagus (n=1), esophageal varices (n=7), and esophageal candidiasis (n=1). Nasal pain was absent or mild in most patients, and adverse events were not observed. Further technical improvement of the E.G. Scan would increase the diagnostic usefulness in future clinical practice.
Injectable hydrogels are useful for numerous biomedical applications, such as to introduce therapeutics into tissues or for 3D printing. To expand the complexity of available injectable hydrogels, ...shear‐thinning and self‐healing granular hydrogels are developed from microgels that interact via guest–host chemistry. The microgel properties (e.g., degradation, molecule release) are tailored through their crosslinking chemistry, including degradation in response to proteases. When microgels of varied formulations are mixed, complex release and degradation behaviors are observed, including after injection to permit cellular invasion.
A modular, guest–host‐mediated approach is used to design an injectable granular hydrogel. Tunable microgels are formed into granular structures that exhibit multiplexed properties based on their microgel design. This generalizable strategy allows complex material design through individual microgels that respond to their local environment.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Carboxyl content and amylose leaching of gamma-irradiated corn starch increased and swelling factor decreased with increasing radiation dose. The apparent amylose content decreased gradually from ...28.7% for native starch to 20.9% for 50 kGy irradiated starch. The proportion of short amylopectin branch chains (DP 6 to 12) increased, while the proportion of longer branch chains (DP greater-than-or-equal 37) decreased with increasing radiation dose. The relative crystallinity and the degree of granule surface order decreased from 28.5% and 0.631 in native starch to 26.9% and 0.605 in 50 kGy irradiated starch, respectively. Pasting viscosity and gelatinization temperatures decreased with an increase in radiation dose. At a high dose (50 kGy), melting of amylose-lipid complex in DSC thermogram was not observed. The rapidly digestible starch (RDS) content slightly decreased up to 10 kGy but increased at 50 kGy. The resistant starch (RS) content slightly decreased at 2 kGy and then increased up to 50 kGy. The slowly digestible starch (SDS) content showed the opposite trend to RS content. Slower irradiation dose rate reduced carboxyl content, swelling factor, and amylose leaching. The apparent amylose content and amylopectin chain length distribution were not significantly affected by dose rate of gamma irradiation. However, the relative crystallinity and gelatinization enthalpy increased with slower dose rate. Slower dose rate decreased RDS and SDS contents, and increased RS content.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A
bstract
Through a mechanism similar to perturbative particle scattering, particles of mass
m
χ
larger than the Hubble expansion rate
H
inf
during inflation can be gravitationally produced at the ...end of inflation without the exponential suppression powers of exp(−
m
χ
/H
inf
). Here we develop an analytic formalism for computing particle production for such massive particles. We apply our formalism to specific models that have been previously been studied only numerically, and we find that our analytical approximations reproduce those numerical estimates well.
The Stimulator of Interferon Genes (STING) pathway initiates potent immune responses upon recognition of DNA. To initiate signaling, serine 365 (S365) in the C-terminal tail (CTT) of STING is ...phosphorylated, leading to induction of type I interferons (IFNs). Additionally, evolutionary conserved responses such as autophagy also occur downstream of STING, but their relative importance during in vivo infections remains unclear. Here we report that mice harboring a serine 365-to-alanine (S365A) mutation in STING are unexpectedly resistant to Herpes Simplex Virus (HSV)-1, despite lacking STING-induced type I IFN responses. By contrast, resistance to HSV-1 is abolished in mice lacking the STING CTT, suggesting that the STING CTT initiates protective responses against HSV-1, independently of type I IFNs. Interestingly, we find that STING-induced autophagy is a CTT- and TBK1-dependent but IRF3-independent process that is conserved in the STING S365A mice. Thus, interferon-independent functions of STING mediate STING-dependent antiviral responses in vivo.
The rapidly increasing application of antibodies has inspired the development of several novel methods to isolate and target antibodies using smart biomaterials that mimic the binding of Fc-receptors ...to antibodies. The Fc-binding domain of antibodies is the primary binding site for e.g., effector proteins and secondary antibodies, whereas antigens bind to the Fab region. Protein A, G, and L, surface proteins expressed by pathogenic bacteria, are well known to bind immunoglobulin and have been widely exploited in antibody purification strategies. Several difficulties are encountered when bacterial proteins are used in antibody research and application. One of the major obstacles hampering the use of bacterial proteins is sample contamination with trace amounts of these proteins, which can invoke an immune response in the host. Many research groups actively develop synthetic ligands that are able to selectively and strongly bind to antibodies. Among the reported ligands, peptides that bind to the Fc-domain of antibodies are attractive tools in antibody research. Besides their use as high affinity ligands in antibody purification chromatography, Fc-binding peptides are applied e.g., to localize antibodies on nanomaterials and to increase the half-life of proteins in serum. In this review, recent developments of Fc-binding peptides are presented and their binding characteristics and diverse applications are discussed.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary Objectives Arthritis with intra-articular inflammation was accompanied by joint pain, swelling, and stiffness leading to significant functional impairment. Thus, regulation of joint ...inflammation is a good therapeutic approach for patients with arthritis. In this study, the effect of low intensity ultrasound (LIUS) applied to an adjuvant-induced arthritic rat model on the synovium was investigated. Design Synovial inflammation was induced by complete Freund's adjuvant (CFA)-injection into the rat knee joint. LIUS (200 mW/cm2 ) was applied on the ipsilateral knee everyday for 10 min beginning 1 day after inflammation induction. The expression of proinflammatory factors and immunohistochemical staining pattern of the synovium were assessed. Results CFA induced an increase of the knee circumference that was significantly diminished by LIUS. Synovial membrane hyperplasia in the ipsilateral joint was also affected by LIUS. The inflammatory mediators, COX-1/2, IL-1β, and iNOS, but not TNF-α, in the synovial membrane were induced after 3 days, and they closely correlated with the degree of edema. In the synovial membrane, the expression of inflammatory mediators was reduced by LIUS. The chemoattractant chemokine receptor CCR5 also was involved. On immunohistochemical analysis, CFA caused increased infiltration of CD11b-positive cells in the synovium. After 3 days, neutrophils, myeloperoxidase (MPO)-positive cells filled the inflammatory core; later, monocytes and macrophages, ionized calcium binding adaptor molecule 1 (Iba1)-positive cells in the periphery infiltrated the core by day 5. LIUS markedly reduced CFA-induced inflammatory cells infiltration. Conclusion LIUS showed a potent anti-inflammatory effect in this animal arthritis model with reduced infiltration of inflammatory cells into the synovium.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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