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• Different scale surfaces are investigated in closed loop two-phase spray cooling. • Fluid distribution on the macro- surface has an important effect on heat transfer. • CHF are improved by 116 % at surface temperature 80 °C on multi-scale surface. • Maximum evaporation efficiency reached 60 % at the chamber pressure of 60 kPa. • Enhancement ratio varies with the surface temperature on structured surfaces. Dielectric liquid spray cooling is a promising way to dissipate heat of high-power electronic devices. Surface modification is a most cost-effective method to enhance spray cooling. Inspired by leaf veins, this paper designs and fabricates macro-scale, micro- and nano- scale, and multi-scale structured surfaces for dielectric liquid spray cooling. The cooling characteristics are tested on a two-phase spray cooling system using HFE-7100. The results reveal that the heat transfer is enhanced on all the structured surfaces. Two bionic leaf vein structures, reticulated veins and parallel veins, are designed for macro-scale structured surfaces. The results show that the former one is superior to the other thanks to its better liquid distribution. For the micro- and nano- scale structured surfaces, due to the larger surface area and higher thermal conductivity, the graphene coating outperforms the carbon nanotube coating in heat transfer. Multi-scale structured surfaces, featured with leaf veins and micro- and nano- coatings, further enhance heat transfer. The heat flux increases by 116 % compared with that of the smooth surface. The evaporation efficiency reaches 60 % at the surface temperature of 80 °C. Furthermore, the effect of surface temperature on the enhancement ratio of heat transfer is analyzed, revealing various enhancement mechanisms of different scaled structured surfaces. [ABSTRACT FROM AUTHOR]

• A liquid nitrogen droplet impacting experimental system is designed and built. • The droplet exhibits spreading, retraction and rebound in the Leidenfrost state. • Liquid nitrogen droplet dynamics are mainly affected by Weber number. • Maximum spreading coefficient exhibits a power-law increase with Weber number. • Maximum rebound coefficient first increases and then decreases with Weber number. Liquid nitrogen droplet impacting a superheated surface is a fundamental phenomenon of liquid nitrogen spray cooling, whereas the mechanisms behind which are still unclear. We designed and developed a visual experimental system to investigate the dynamics of a liquid nitrogen droplet impacting a superheated surface under cryogenic conditions. The impact dynamics of the liquid nitrogen droplet at the Leidenfrost state are captured, and the effects of Weber number (We) and surface temperature on the spreading and rebound characteristics of the droplet are analyzed. The findings show that the droplet exhibits spreading, retraction and rebound at a low We. Droplet spreading and rebound characteristics are mainly affected by We while insensitive to surface temperature. The maximum spreading coefficient exhibits a power-law increase with We , while the maximum rebound coefficient shows an upward and then downward trend with We. The dimensionless maximum spreading time, dimensionless residence time, and dimensionless maximum rebound time show power-law increase with We. Corresponding fitting correlations for these factors for liquid nitrogen droplets are also proposed. This study contributes to an in-depth understanding of the impact dynamics of cryogenic liquid droplet under cryogenic conditions. [ABSTRACT FROM AUTHOR]

Abstract The efficacy of nonthermal plasma-activated water (PAW) in the decontamination of mung bean sprouts was evaluated in this work. After being treated with PAW for 30 min, the populations of total aerobic bacteria and total yeasts and moulds on mung bean sprouts were decreased by 2.32- and 2.84- log 10 CFU/g, respectively. The PAW treatment had no significant effect on the antioxidant potential of mung bean sprouts as shown by using 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH•) scavenging activity assay, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method, and ferric reducing antioxidant power (FRAP) assay (p > 0.05). Additionally, the PAW treatment caused no significant changes in the total phenolic and flavonoid contents, nor the sensory characteristics of mung bean sprouts (p > 0.05). Reactive species such as nitrates, nitrites, and H 2 O 2 were generated in PAW, which presumably contributed to the disinfection efficacy of PAW. These data show that PAW can be used as a promising nonthermal technology for the control of microbial contamination in sprouts. Industrial relevance Edible sprouts are common food ingredients across the world. However, sprouts can be contaminated by pathogenic microorganisms, which may result in health risks to humans. Recently, PAW has been shown to be a safe and effective method for food surface sanitation. However, the application of PAW in the microbial control for sprouts is less investigated. In this study, the influences of PAW on the microbial load, chemical and sensory quality of mung bean sprouts were investigated for the first time. The results showed that PAW could effectively inactivate bacteria and yeasts and moulds on mung bean sprouts without resulting in significant changes in the antioxidant capacities, total phenolic and flavonoid contents, and sensory characteristics of mung bean sprouts. These data indicated that PAW can be used as a promising nonthermal technology for reducing microbial populations on sprouts. Highlights • A 30-min PAW treatment of mung bean sprouts reduced total aerobic bacterial counts by 2.32-log 10 CFU/g. • PAW effectively reduced microbial loads on mung bean sprouts. • PAW had no adverse impacts on physicochemical properties of mung bean sprouts. • Reactive species played a pivotal role in the inactivation efficacy of PAW. • PAW is a promising method for the preservation of mung bean sprouts. [ABSTRACT FROM AUTHOR]

Despite recent vigorous progress in synthesis of monofunctional electrocatalysts for hydrogen evolution reaction (HER) or oxygen evolution reaction (OER), it remains challenging to develop bifunctional electrocatalysts for efficient overall water splitting. Herein, we report the crafting of MoC 2 -doped NiFe alloy nanoparticles (NPs) encapsulated within a-few-layer-thick N-doped graphene (denoted NG-NiFe@MoC 2 ) via one-step calcination of hybrid precursors containing polymer-encapsulating binary Prussian blue analogues NPs and Mo 6+ cations. The resulting NG-NiFe@MoC 2 nanohybrids were exploited as electrocatalysts and exhibited excellent performance on either HER or OER separately as a direct consequence of the synergistic effects of unique compositions (i.e., MoC 2 dopants and NiFe alloy NPs; both exerted profound influence on HER and OER) and advantageous architecture (i.e., a-few-layer-thick N-doped graphene encapsulating shell). Remarkably, an alkaline electrolyte capitalizing on NG-NiFe@MoC 2 nanohybrids as bifunctional electrocatalysts achieved overall water-splitting (i.e., concurrent HER and OER) current density of 10 mA cm −2 at a low potential of 1.53 V over a period of 10-h operation, outperforming the precious Pt/C//RuO 2 counterpart. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the effects of dielectric barrier discharge (DBD) plasma on inactivation of spoilage yeast Zygosaccharomyces rouxii ( Z. rouxii ), in apple juice. Results showed that DBD plasma treatment at 90 W for 140 s resulted in about 5-log reduction of Z. rouxii in apple juice. The levels of extracellular nucleic acids and proteins as well as contents of H 2 O 2 and NO 2 − in yeast extract-peptone-dextrose (YPD) medium increased significantly after DBD plasma treatment at 90 W for 40–200 s. The increases in membrane permeability and generation of reactive species would likely contribute to DBD plasma-mediated inactivation of Z. rouxii . DBD plasma caused significant changes in pH, titratable acidity, and certain color parameters of apple juice, but had no effect on the contents of total soluble solids, reducing sugar, and total phenolics. This study provides key implications for the application of DBD plasma in fruit juice processing. [ABSTRACT FROM AUTHOR]

Aiming to improve the heat transfer of phase change spray cooling, experiments were conducted to investigate the influences of surface roughness, nozzle inlet sub-cooling degree and nozzle-to-surface distance. A commercial full cone nozzle was employed to spray the working fluid R134a towards a circular cooling surface in a closed loop system. It is found that rougher cooling surface can bring forward the nucleate boiling, leading to enhanced heat transfer and broadened high-efficiency heat transfer range. Higher nozzle inlet sub-cooling degree can retard the flash evaporation of R134a inside the nozzle passageway and increase the mass flowrate correspondingly. As a result, the spray cooling performance is greatly improved. With regard to the influence of nozzle-to-surface distance, the optimal heat transfer capability is obtained at 16 mm. It is slightly larger than the distance at which the circular cooling surface is overlapped with the cross-section of the spray field. For purpose of gaining a deeper insight into the underlying reason, a CFD model based on the Euler-Lagrange approach was established to simulate the atomization process. The results show that the nozzle-to-surface distance not only affects the spray field coverage area, but also has some impacts on the microscopic atomization characteristics. The combined action of these two factors accounts for the occurrence of the optimal nozzle-to-surface distance. [ABSTRACT FROM AUTHOR]

The ability to develop low-cost highly efficient electrocatalyst for oxygen evolution reaction (OER) is key to the overall water splitting device that represents a viable and promising source of alternative energy. Herein, we crafted three-dimensional (3D) network comprising nitrogen-doped graphitic carbon-coated heterojunctions (denoted NC-Ni 0.36 Fe 0.64 /MnO x ) via one-step calcination of hybrid precursors containing ternary Prussian blue analogues and polymers. The NC-Ni 0.36 Fe 0.64 /MnO x nanocomposites were then exploited as catalysts for OER, displaying exceptional performance with a small overpotential of 300 mV to reach 10 mA cm −2 , a low Tafel slope of 43 mV/dec and an outstanding stability without deactivation over a 10-h OER. Notably, compared to commercial RuO 2 catalysts, NC Ni 0.36 Fe 0.64 /MnO x catalysts demonstrated much lower overpotential and Tafel slope. The excellent OER performance can be attributed to the presence of high-valence oxidized metal species (Ni 2+ , Fe 2+ and Mn 2+ ) at the heterostructured interface as well as pyridinic N-doped carbon species on highly conductive graphitic carbon network, thus greatly facilitating the electron-withdrawing from OH − and thus charge transfer during OER. This simple yet effective strategy may open new possibilities for creating a wide range of low-cost, high-efficiency, non-precious transition metal OER catalysts for the overall water splitting. [ABSTRACT FROM AUTHOR]

Anti-microtubule therapy represents one of the most strategic cancer therapeutics. Tublin inhibitor such as paclitaxel (PTX) is well known to disturb the dynamic nature of microtubules, being considered as the first-line drug for various malignancies. However, PTX does not show favorable clinical outcomes due to serious systemic toxicities and low selectivity. The development of PTX delivery systems and combinational therapies has been conducted to enhance PTX efficacy with poorly defined mechanisms. Herein, we introduced a reactive oxygen species producible composite liposome based on a new photosensitizer sinoporphyrin sodium (DVDMS) to enhance the therapeutic effect of PTX through photochemical stimulation, and more importantly, the pivotal molecular regulation mechanisms were specifically explored. Compared with DVDMS-liposome (DL) or PTX-liposome (PL), the composite liposome DVDMS-PTX-liposome (PDL) exhibited a superior anti-tumor advantage following laser irradiation against MCF-7 breast cancer. The localized PTX release after PDL administration greatly decreased the drug dosage and laser power required, leading to much higher safety and lower costs. In vitro, the combined treatment significantly suppressed cell viability and potentiated cell apoptosis. The apoptotic central regulator Mcl-1 as a favorable target, was evaluated in association with photochemically enhanced sensitivity to anti-tubulin chemotherapeutics. Phosphorylation of Mcl-1 led to its direct degradation with the proteasome system, making it relatively unstable and potentiating cell death resulting from photochemical synergy via PDL plus laser irradiation. Further, a decrease in ATP production and glycolysis after PDL plus laser would prevent the possible energy-switch and apoptosis-escape by PTX alone treatment, thereby resulted in increased cell death in combinational therapy. Systemic administration of PDL followed by in vivo photochemotherapy achieved significantly improved therapeutic effects compared to either alone. And, the intrinsic fluorescence of DVDMS facilitated real-time imaging of PDL in tumors. Therefore, the present strategy with details at the molecular regulation could be a promising platform for antitublin chemotherapeutics. [ABSTRACT FROM AUTHOR]

Spray cooling with liquid nitrogen as the working fluid has been widely employed in a plenty of fields requiring cooling at cryogenic temperature, such as the cryogenic wind tunnels and cooling super-conducting magnets. In this study, we built a liquid nitrogen spray system and experimentally investigated the influence of injection pressure difference on the droplet size distribution and the spray cone angle. The measurements using particle size analyser show increasing the injection pressure difference improves the atomization, as indicated by the homogenization and reduction of the droplet size. The initial spray cone angle is insensitive to the injection pressure difference. However, the far-field spray cone angle decreases dramatically with increasing the injection pressure difference. The results could enrich our knowledge of spray cooling of cryogenic fluids and benefit the design of cryogenic spray cooling systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three distinct collision regimes of two nitrogen droplets are revealed. • Collision dynamics of water droplets are compared with those of nitrogen droplets. • Effects of surface tension and viscosity on droplet collision are illustrated. • The minimum kinetic energy for separation upon droplet collision is shown. Collision of nitrogen droplets is a basic phenomenon in an array nitrogen spray cooling system, while the understanding on which is still lacking. We conduct a numerical simulation to investigate the collision dynamics of two nitrogen droplets in a low-temperature environment under various Weber numbers, Reynolds numbers and impact parameters, and simulation of collision of two water droplets is conducted for comparison. Incompressible Navier-Stokes equations are solved to simulate the colliding process, and Volume of Fluid (VOF) method and adaptive mesh refinement technique are used to capture gas-liquid interface. Three regimes of collision are found for nitrogen droplet collision, including coalescence, reflection separation and stretching separation. Upon collision, a lower surface tension and lower viscous dissipation consume less initial kinetic energy, which is conducive to the separation of droplets. Compared with water droplets, collision of nitrogen droplets easily enables breakage due to the lower surface tension and viscous dissipation. Separation of nitrogen droplets leads to the increase of secondary droplet number and enlarges heat transfer area of droplets and gas, which would enhance droplet vaporization and temperature descendence of the environment. [ABSTRACT FROM AUTHOR]

Abstract: It is reported that a dual-layer carbon film on SiC wafer is prepared using carbide-derived carbon (CDC) process with subsequent chemical vapor deposition (CVD). The dual-layer film includes a sub-layer of CDC and a top layer of CVD, which are prepared by chlorination of SiC and pyrolysis of CCl4 at high temperature respectively. The CDC and CVD layers are mainly amorphous. And similar dispersion effects are observed in the Raman spectra, although the D-band position of the CVD layer shifts to higher wavenumber (~1354cm−1) than that of the CDC layer (~1337cm−1). Surface chemistry analysis suggests that the unstable chemical bonds, mainly C―Cl, as well as dangling bonds in the CDC layer play an important role in promoting the nucleation of CVD carbon. The surface morphology evolvement from SiC wafer to CDC layer and to dual-layer film is investigated by atomic force microscopy [AFM] and field emission scanning electronic microscopy [FESEM]. The nanoporous surface formed in the CDC process is favorable for capturing carbon species from the gas phase and can act as a “seedbed” for the nucleation and growth of CVD layer. The primary tribological study indicates that the dual-layer film shows great advantages in friction reduction and wear resistance with comparison to SiC and CDC layer, suggesting its potential in lubrication for SiC-based moving components. [Copyright &y& Elsevier]

Abstract: In this paper, the composition, structure, morphology and high vacuum tribological properties of three DLC-based solid–liquid lubricating coatings were investigated after atomic oxygen (AO) and ultraviolet (UV) irradiations. The research results showed that AO and UV irradiations induced the structural changes, including oxidation, bond breaking and crosslinking reactions of the DLC film and liquid lubricants, and the destruction of AO irradiation was much stronger than that of UV irradiation. After irradiations, the friction coefficient of the DLC-based solid–liquid lubricating coatings was lower than that before irradiation (except for AO irradiation), but the wear rates were larger due to irradiation destruction. [Copyright &y& Elsevier]

Abstract: Phase change spray cooling is known as an effective method to remove heat from high-power electronic devices due to its high heat transfer efficiency and high critical heat flux (CHF). In this study, a closed-cycle spray cooling system with R22 as the coolant was designed and built, and the system cooling performance including the heat transfer coefficient, cooling surface temperature and CHF was experimentally investigated with nozzle inlet pressure in the range of 0.6–1.0MPa. The system shows a great capability in removing high heat flux from the cooling surface at a relatively low temperature. As the nozzle inlet pressure increases, the value of CHF first increases and then decreases slightly. The maximum CHF of 276.1Wcm−2 is achieved at the nozzle inlet pressure of 0.8MPa and the corresponding cooling surface temperature is 26.8°C. [Copyright &y& Elsevier]

Objective: To determine the relationship between progesterone receptor membrane component-1 (PGRMC1) expression and the outcome of IVF treatment. Design: A prospective study in which PGRMC1 messenger RNA (mRNA) levels, methylation status of the Pgrmc1 promoter, and the presence of point mutations within Pgrmc1 were obtained from granulosa (GC)/luteal cells of women undergoing controlled ovarian hyperstimulation (COH). Setting: Fertility center/basic science laboratory. Patient(s): Eighty-five patients undergoing IVF treatment and 10 women who were undergoing COH for the purpose of oocyte donation were included in this study. Intervention(s): None. Main Outcome Measure(s): The PGRMC1 measurements were correlated with clinical outcomes, such as number of follicles, number of retrieved oocytes, and ongoing pregnancy rates (PR). Result(s): The PGRMC1 mRNA levels within GC/luteal cells of 18% of IVF patients were >2.25-fold higher than those of oocyte donors. Individuals with elevated PGRMC1 mRNA levels had 30% fewer large follicles and fewer oocytes retrieved. The elevated PGRMC1 mRNA levels were associated with an increase in the methylation of Pgrmc1 promoter. Conclusion(s): In patients with elevated PGRMC1 mRNA levels, gonadotropin-induced follicle development is attenuated, although sufficient numbers of follicles develop to allow for ET and subsequent pregnancy. [ABSTRACT FROM AUTHOR]

Abstract: hOGG1 protein excises the 8-hydroxy-2′-deoxyguanine (8-OHdG) which is associated with type 2 diabetes mellitus (T2DM). Our aim of this work is to explore whether the polymorphisms of hOGG1 gene are associated with T2DM. We screened the polymorphisms in the 5′-UTR (c.−18G>T, c.−23A>G, c.−45G>A and c.−53G>C) and c.977C>G (Ser326Cys) in exon 7 of hOGG1 gene. A case–control study indicated that c.−23A/G heterozygote was markedly associated with diabetes (P =0.004, OR=2.648, 95%CI=1.355–5.176) and with an increased level of C-peptide (705.00 versus 545.91pmol/L, P =0.044). Furthermore, a significantly increased risk of T2DM was observed in the subjects carrying heterozygous variant of c.−23A>G and homozygous mutation of Ser326Cys (OR=3.684, 95%CI=1.400–9.697). The promoter activity of the variant allele c.−23G decreased 30–40% in Hela and HEK293 cell lines. In conclusion, the variant c.−23A>G of hOGG1 gene could decrease the gene promoter activity and was a risk factor for T2DM. [Copyright &y& Elsevier]

Tectorigenin is one of the main components in rhizomes of Iris tectorum, which is traditionally used to treat disorders such as hepatic cirrhosis caused by fibrosis. Idiopathic pulmonary fibrosis (IPF), one of the most common interstitial lung diseases, is caused by accumulation of fibroblasts in lungs. Aim of the study: In this work we sought to examine the effects of tectorigenin on pulmonary fibroblasts in the IPF animal model and investigated the molecular mechanism (microRNA regulation) of tectorigenin treatment. Materials and methods: A well-known animal disease model of pulmonary fibrosis in rat was established by intratracheally instilling of bleomycin. In vitro cultured pulmonary fibroblasts in bleomycin-treated rats and in controls were treated with or without tectorigenin. Comparative analyses of cell proliferation, apoptosis and cell cycle of pulmonary fibroblasts in bleomycin-treated rats and in controls were performed. Expression of miR-338* and its candidate gene LPA1 related to IPF of tectorigenin-treated pulmonary fibroblasts in bleomycin-treated rats were further investigated. Results: Tectorigenin significantly inhibited the proliferation of pulmonary fibroblasts in bleomycin-treated rats but not in controls. However, no altered cell cycle and apoptosis of pulmonary fibroblasts in bleomycin-treated rats and in controls was observed after tectorigenin treatment. Tectorigenin remarkably enhanced miR-338* expression of pulmonary fibroblasts in bleomycin-treated rats and downregulated LPA1 in the protein level. Conclusions: Tectorigenin inhibits the proliferation of pulmonary fibroblasts in vitro and enhances miR-338* expression, which might in turn downregulate LPA1. This indicates a potential inhibitory role of tectorigenin on the pathogenesis of IPF. [Copyright &y& Elsevier]

The effect of substrate temperature is investigated experimentally on the ice profile of an impact water droplet. A hydrophilic substrate, a relatively high impact velocity which can lead to a larger contact area, and a low surface temperature are employed aiming at enhancing the heat transfer rate through the droplet. The frozen droplet is uniquely central-concave at low surface temperatures, in contrast to the widely observed central-pointy ice formed at cold surfaces. The formation of the central-concave icing is attributed to the additional interior circular-like freezing front advancing both upwards and outwards during the solidification. Upon decreasing the surface temperature, the nucleation is triggered earlier, and the freezing rate is higher than that of a quasi-steady droplet freezing on a similar subcooled surface due to the impact-induced flattening of the droplet. A freezing regime map described by the dimensionless number representing the heat conduction rate through the substrate and Weber number consists of two regimes for the formation of the central-pointy and central-concave ice profile respectively. Unlabelled Image [ABSTRACT FROM AUTHOR]

• Significant change of metabolites was observed in CAG patients treatment koumiss. • Several gut microbes might be associated with the modulation of fecal metabolites. • The koumiss treatment also alleviated gut inflammation. Our previous research showed that koumiss intervention could alleviate symptoms of chronic atrophic gastritis (CAG) via the modulation of gut microbiota. The present work aimed to further decipher the mechanism of the observed functional effect by analyzing changes in the fecal metabolomes of these patients. Significant modulation was observed in the levels of metabolites relating to several pathways, namely biosynthesis of primary and secondary bile acid, as well as metabolism of unsaturated fatty acid, linoleic acid and arachidonic acid, phenylalanine, and retinol. Koumiss treatment also decreased the level of some fecal proinflammatory markers, as evidenced by significant decrease in the fecal interleukin 38 (P < 0.05) and numerical decrease in tumor necrosis factor-α after 60-days of koumiss consumption. Our data together suggest that koumiss can serve as functional food that improves CAG symptoms via integrative modulation of the host immunity, gut microbiota and metabolome. [ABSTRACT FROM AUTHOR]

• IL-1β stimulates MCP-1 production in alveolar type II epithelial cells. • IKK/NF-κB p65, JNK/c-Jun, and C/EBPβ/δ signaling pathways are activated by IL-1β. • IKK/NF-κB p65/κB element, JNK/c-Jun/AP-1 site, C/EBPβ/δ/C/EBP binding site, and Sp1/Sp1 element contribute to MCP-1 transcription. During acute lung injury, a large number of monocytes are recruited into the pulmonary tissue, which is mainly mediated by local production of monocyte chemotactic protein 1 (MCP-1). As an essential component of the lung tissues, alveolar type II epithelial cells are one of the major sources of MCP-1. Therefore, uncovering the mechanism whereby MCP-1 production is regulated in the alveolar type II cells will provide a pivotal theoretical basis for clinical intervention in acute lung injury. In the current study, we find that there is a κB binding site in the MCP-1 promoter region, and mutation of the site leads to reduced production of MCP-1 in alveolar type II epithelial cells. In contrast, overexpression of NF-κB p65 significantly increases MCP-1 expression. Furthermore, we elucidate that IKKα/β—NF-κB p65 signaling pathway and phosphorylation of serine 534 in NF-κB p65 are required for the maximal expression of MCP-1. Also, Activator protein 1 (AP-1) site in the promoter region and JNK1/2—c-Jun signaling are required for MCP-1 generation in alveolar type II epithelial cells. Moreover, a CCAAT/enhancer-binding protein (C/EBP) element is identified in the MCP-1 promoter region through the point mutation technique, and further experiments demonstrate that both C/EBPβ and C/EBPδ are involved in basic and IL-1β-mediated MCP-1 expression. Of note, specificity protein 1—Sp1 expression is not changed in alveolar type II epithelial cells incubated with IL-1β, but it still control MCP-1 production by binding to the consensus sequence in the promoter region. More importantly, we find that the results derived from the cell line—MLE-12 cells and primary cells are consistent. Taken together, our data provide insights into the molecular mechanism how MCP-1 expression in inflammatory alveolar type II epithelial cells is regulated at transcription level. [ABSTRACT FROM AUTHOR]

Highlights • TNF-α stimulates IL-6 production in alveolar type II epithelial cells. • JNK/c-Jun signaling, C/EBPδ, and IKK/NF-κB p65 pathways are all activated by TNF-α. • JNK/c-Jun/AP-1 site, C/EBPδ/C/EBP binding site, and IKK/NF-κB p65/κB element contribute to IL-6 transcription. Abstract Although participation of IL-6 in lung inflammation has been widely elucidated, the transcriptional regulation of its generation in alveolar type II cells stimulated by TNF-α remain unclear. Here, we find that TNF-α significantly induces IL-6 production, and TNF-α induction of IL-6 is mainly regulated at transcriptional level. Upon stimulated by TNF-α, Activator Protein-1 (AP-1)-mediated transcriptional activity is apparently increased in alveolar type II epithelial cells, which might be derived from elevated phosphorylation of JNK and subsequent activation of c-Jun. Either down-regulation of c-Jun or the AP-1 site mutation leads to significant reduction of IL-6 expression. In contrast, ectopic expression of c-Jun notably increases IL-6 generation. So, c-Jun, one of the AP-1 family members, plays a pivotal role in TNF-α-induced IL-6 generation. CCAAT/enhancer binding protein δ (C/EBPδ) expression is significantly amplified by TNF-α, which may contribute to the rise of C/EBP activity in alveolar type II cells. C/EBPδ shRNA treatment results in attenuation of IL-6 expression in the cells, which is consistent with data by introduction of mutations into the C/EBP site in the promoter. However, overexpression of C/EBPδ greatly increases the IL-6 promoter activity. In addition, data regarding another transactivator in the family—C/EBPβ show that it does not affect IL-6 production. We also find that the IKK/NF-κB p65 pathway is activated in TNF-α-treated alveolar type II epithelial cells, and plays an essential role in positive regulation of IL-6 expression in TNF-α-treated alveolar type II epithelial cells via knockdown or forced expression of NF-κB p65, or elimination of κB sites in the IL-6 promoter. Notably, IL-6 promoter-driven luciferase production in primary alveolar type II epithelial cells can also be increased by the ectopic expression of c-Jun, C/EBPδ, and NF-κB p65, respectively. Collectively, our data provide insights into molecular mechanism involved in IL-6 expression in alveolar type II epithelial cells on TNF-α treatment, which provides a theoretical basis for specific inhibition of IL-6 production at the transcriptional level. [ABSTRACT FROM AUTHOR]

The cavitating flow of cryogenic liquid through a spray nozzle is influenced by many factors, such as unique thermophysical properties of cryogenic liquid, the inflow temperature and the complicated geometrical structure of the spray nozzle. The geometrical parameters of liquid nitrogen spray nozzles have a profound impact on cavitating flow which in turn affects spray atomization characteristics and cooling performance. In present study, CFD simulations are performed to investigate influence of the nozzle geometry on the liquid nitrogen cavitating flow. The mixture model is used to describe the liquid-vapor two phase flow, and both the cavitation and evaporation are considered for the phase change. The predictions of mass flow of liquid nitrogen spray are validated against experimental results. The effects of geometric parameters, including the outlet orifice diameter and the length of nozzle, the inlet edge angle of orifice, the inlet corner radius of orifice, the orifice shape and different positions of swirl vanes, are investigated under a wide range of pressure difference and inflow temperature. The results show that the effects of geometric parameters on cavitating flow show different trends under subcooled conditions compared with saturated temperature conditions. The flow characteristics are more affected by the changes of the inlet edge angle, the inlet corner radius, and the orifice shape. The insert of swirl vanes has an effect on the distribution of the cavitated vapor within the orifice, but it has little influence on flow characteristics. The results could enrich our knowledge of liquid nitrogen cavitating flow in spray nozzles of various shapes. [ABSTRACT FROM AUTHOR]

Soybean trypsin inhibitor (STI) is considered as one of the most important anti-nutritional factors in soybeans. The objective of this study was to investigate the impacts and underling mechanisms of dielectric-barrier discharge (DBD) plasma on STI activities. The results shown that DBD plasma treatment significantly induced the inactivation of STI in soymilk and Kunitz-type trypsin inhibitor from soybean (SKTI) in a model system. After exposure to DBD plasma at 51.4 W for 21 min, the STI activities of soymilk were reduced by 86.1%. Affter being treated by DBD plasma, the intrinsic fluorescence and surface hydrophobicity of SKTI were significantly decreased, while the sulfhydryl contents were increased. It is assumed that DBD plasma-induced conformational changes and oxidative modification might contribute to the inactivation of SKTI. In summary, DBD plasma technology is a potential alternative to heat treatment for the inactivation of anti-nutritional substances in food legumes. [ABSTRACT FROM AUTHOR]

Spray cooling with cryogen could achieve lower temperature level than refrigerant spray. The internal flow conditions within spray nozzles have crucial impacts on the mass flow rate, particle size, spray angle and spray penetration, thereby influencing the cooling performance. In this paper, CFD simulations based on mixture model are performed to study the cavitating flow of liquid nitrogen in spray nozzles. The cavitation model is verified using the experimental results of liquid nitrogen flow over hydrofoil. The numerical models of spray nozzle are validated against the experimental data of the mass flow rate of liquid nitrogen flow through different types of nozzles including the pressure swirl nozzle and the simple convergent nozzle. The numerical studies are performed under a wide range of pressure difference and inflow temperature, and the vapor volume fraction distribution, outlet vapor quality, mass flow rate and discharge coefficient are obtained. The results show that the outlet diameter, the pressure difference, and the inflow temperature significantly influence the mass flow rate of spray nozzles. The increase of the inflow temperature leads to higher saturation pressure, higher cavitation intensity, and more vapor at nozzle outlet, which can significantly reduce mass flow rate. While the discharge coefficient is mainly determined by the inflow temperature and has little dependence on the pressure difference and outlet diameter. Based on the numerical results, correlations of discharge coefficient are proposed for pressure swirl nozzle and simple convergent nozzles, respectively, and the deviation is less than 20% for 93% of data. [ABSTRACT FROM AUTHOR]

Functionally enhanced polyether-bridged amidopyridinium dicationic ionic liquids for highly efficient and sustainable fixation of CO 2 to cyclic carbonates. [Display omitted] • Polyether-bridged amidopyridinium dicationic ionic liquids were synthesized. • An enhanced activity was observed in the cycloaddition reaction. • At a very low loading of 0.01 mol%, the TON value is as high as 7700. • The synergistic activation of epoxides by two amidopyridinium cations. Task-specific ionic liquids integrated with multi-active sites display promising potential for use in the cycloaddition reaction of CO 2 and epoxides. Utilizing the functional enhancement strategy, we successfully synthesized a novel range of polyether-bridged amidopyridinium dicationic ionic liquids (PE-PyDILs) via efficient bisamidation and biquaternization reactions. Under relatively mild reaction conditions, PE-PyDILs can catalyze the coupling of CO 2 with various epoxides to produce cyclic carbonates in quantitative yields, demonstrating an enhanced effectiveness and a longer service life compared to previous DILs. At a very low loading of 0.01 mol%, the TON value is as high as 7700. The excellent catalytic performance can be attributed to the intramolecular cooperative activation of epoxides with two amidopyridinium cations bridged by polyether, as supported by the spectroscopic analysis and kinetic studies. This mechanism led to a reduction in activation energy and improved the efficiency of the cycloaddition reaction. [ABSTRACT FROM AUTHOR]

Neuronal nitric oxide synthase (nNOS) plays a pivotal role in the pathological process of neuronal injury in the development of epilepsy. Our previous study has demonstrated that nitric oxide (NO) derived from nNOS in the epileptic brain is neurotoxic due to its reaction with the superoxide radical with the formation of peroxynitrite. Neuropeptide Y (NPY) is widely expressed in the mammalian brain, which has been implicated in energy homeostasis and neuroprotection. Recent studies suggest that nNOS may act as a mediator of NPY signaling. Here in this study, we sought to determine whether NPY expression is regulated by nNOS, and if so, whether the regulation of NPY by nNOS is associated with the neuronal injuries in the hippocampus of epileptic brain. Our results showed that pilocarpine-induced temporal lobe epilepsy (TLE) mice exhibited an increased level of nNOS expression and a decreased level of NPY expression along with hippocampal neuronal injuries and cognition deficit. Genetic deletion of nNOS gene, however, significantly upregulated hippocampal NPY expression and reduced TLE-induced hippocampal neuronal injuries and cognition decline. Knockdown of NPY abolished nNOS depletion-induced neuroprotection and cognitive improvement in the TLE mice, suggesting that inhibition of nNOS protects against hippocampal neuronal injuries by increasing neuropeptide Y expression in TLE mice. Targeting nNOS-NPY signaling pathway in the epileptic brain might provide clinical benefit by attenuating neuronal injuries and preventing cognitive deficits in epilepsy patients. [Display omitted] • NOS enzymatic activity is increased in the hippocampus of TLE mice. • Inhibition of nNOS suppresses TLE-induced cognitive impairment. • Inhibition of nNOS suppresses TLE-induced neuroinflammation and neuronal injuries. • nNOS negatively regulates NPY expression in the hippocampus of TLE mice. • Inhibition of nNOS suppresses TLE-induced neural injuries in a NPY-dependent manner. [ABSTRACT FROM AUTHOR]

Spray cooling is one of the promising technologies in heat removing for high power density equipment, especially for the equipment with high heat flux surface. R134-a is one of the most prospective alternative refrigerants of R22 due to the zero ODP, low GWP, non-toxicity and non-inflammability, it is necessary to do comparative study on the heat transfer characteristics of R22 and R134-a in spray cooling. In this article, two closed loop spray cooling test rigs with the same spray nozzle are established to investigate the thermal performance of R22 spray cooling and R134-a spray cooling. The main parameters such as critical heat flux (CHF), heat transfer coefficient and target surface temperature are compared in the same thermal condition. The CHF of R134-a spray is lower due to the lower latent heat. The heat transfer coefficient of R22 spray is higher than that of R134-a spray with the same spray chamber pressure. However, R134-a spray cooling could replace R22 spray cooling in the phase change heat transfer region when the heat flux is less than 80 W cm −2 . [ABSTRACT FROM AUTHOR]

The metalloproteinase ADAM10 is the most important amyloid precursor protein (APP) α-secretase, preventing the deposit of neurotoxic amyloid β (Aβ) peptide and generating a soluble APP fragment (sAPP α) with neurotrophic functions. Recent studies have suggested that ADAM10 also play a role in the pathogenesis of inflammatory CNS diseases, such as multiple sclerosis (MS). Demyelination is the hallmarks of MS but the mechanisms involved remain unclear. Here in this study, we examined the role that ADAM10 might play in the cuprizone-induced demyelination model. Our results demonstrated that ADAM10 expression and sAPP α production were significantly reduced in the corpus callosum in response to cuprizone treatment. Overexpression of ADAM10 increased sAPP α production and suppressed demyelination as well as neuroinflammation and oxidative stress in cuprizone-induced demyelination model. Pharmacological inhibition of ADAM10 activity, however, abrogates the protective effect of ADAM10 against demyelination, neuroinflammation and oxidative stress. It has been reported that CNS demyelination may induce seizure activity. Here, we found that overexpression of ADAM10 reduced seizure susceptibility in cuprizone-induced demyelination model, suggesting that ADAM10-derived sAPP α suppresses demyelination and reduces seizure susceptibility via ameliorating neuroinflammation and oxidative stress in cuprizone-induced demyelination model. [Display omitted] • ADAM10 expression is reduced in cupizone-induced demyelination. • ADAM10 protects against cupizone-induced myelin structural protein loss. • ADAM10 suppresses CPZ-induced mature oligodendrocytes loss and oligodendrocyte progenitor cells proliferation. • Inhibition of ADAM10 abrogates the protective effect of ADAM10 against demyelination and oxidative stress. • ADAM10 suppresses CPZ-induced seizure susceptibility. [ABSTRACT FROM AUTHOR]

Electromyography (EMG) plays a vital role in detecting medical abnormalities and analyzing the biomechanics of human or animal movements. However, long-term EMG signal monitoring will increase the bandwidth requirements and transmission system burden. Compressed sensing (CS) is attractive for resource-limited EMG signal monitoring. However, traditional CS reconstruction algorithms require prior knowledge of the signal, and the reconstruction process is inefficient. To solve this problem, this paper proposed a reconstruction algorithm based on deep learning, which combines the Temporal Convolutional Network (TCN) and the fully connected layer to learn the mapping relationship between the compressed measurement value and the original signal, and it has been verified in the Ninapro database. The results show that, for the same subject, compared with the traditional reconstruction algorithms orthogonal matching pursuit (OMP), basis pursuit (BP), and Modified Compressive Sampling Matching Pursuit (MCo), the reconstruction quality and efficiency of the proposed method is significantly improved under various compression ratios (CR). • Solve the problem of poor compressed sensing reconstruction effect of EMG. • Propose a novel EMG compressed sensing reconstruction method TCNN. • TCNN improves the reconstruction quality and efficiency of EMG. • Obtain the most suitable compressed ratio for EMG recovery. [ABSTRACT FROM AUTHOR]

• Mass flow rates of cryogenic multi-nozzle spray were experimentally investigated. • Internal flow characteristics of liquid nitrogen were revealed by numerical studies. • Relation between mass flow rates basically matches relations between nozzle numbers. The multi-nozzle spray cooling with liquid nitrogen can achieve high heat transfer rate and uniform temperature for a large-scale environmental simulation system. The understanding of the flow characteristics is crucial to the accurate control of the mass flow rates and the temperature distribution in a cryogenic system. This article combines the experimental and numerical approach to reveal the external and internal flow characteristics of the multi-nozzle spray with liquid nitrogen. It is found that a higher injection pressure is followed by an increasing mass flow rate under a given nozzle combination. The number and position of the low-temperature region in the downstream field correspond to the number and the arrangement of spraying nozzles under each combination. The pressure differences have little effect on the spray cone angle of a single-nozzle. The flow swirl is induced by the slotted swirl in the nozzle chamber and the cavitation is caused by the abrupt change structure at the orifice. In the absence of the friction and the resistance, the ratio of the mass flow rate in the multi-nozzles to that in the single-nozzle is basically equal to the ratio of the nozzle numbers. And the nearly equal amount of liquid nitrogen flows into each single nozzle of a multi-nozzle array under the varied injection pressure and inlet temperature conditions. The experimental research and the theoretical analysis are to provide insights on the practical engineering application of the multi-nozzle spray cooling in a cryogenic environmental simulation system. [ABSTRACT FROM AUTHOR]

Transcranial modulation of primary cilia may provide new opportunities in the treatment of neurodegenerative diseases. This study investigates the effect of non-invasive low-intensity pulsed ultrasound (LIPUS) stimulation on primary cilia of rat hippocampal neurons. Three hours of LIPUS stimulation significantly reduced the incidence rate and length of cilia on cultured neurons (p < 0.01). Similarly, increasing the duration and intensity of LIPUS stimulation decreased the incidence and length of cilia. LIPUS stimulation improved c-fos expression when it was delivered to CA1 of the intact hippocampus of rats. And prolonged LIPUS stimulation (frequency: 0.5 MHz, pulse repetition frequency: 500 Hz, duty cycle: 5%, Ispta: 255 mW/cm2, 10 min/d, 10 d) caused a statistically significant reduction in the incidence rate (p < 0.05) and length of primary cilia (p < 0.01) of neurons in rat CA1 hippocampus. These results indicate the promising potential of LIPUS stimulation in the treatment of primary cilium-related brain diseases. [ABSTRACT FROM AUTHOR]

Abstract As one amorphous carbon consisting of sp2 and sp3 bonding, diamond-like carbon (DLC) films present excellent tribological characteristics. Meanwhile, frictional properties could present great complexity with the varied interaction. In this work, research on the tribological performances of hydrogenated DLC films under the various isobutane conditions, which was similar to some polar fluids, was carried out. The results showed that friction coefficient increased with the isobutane amount. And the wear was constant after a certain amount of isobutane was adsorbed. Combining these experimental results with models, the mechanism has been proposed. It was the isobutane molecules physisorbed on the interface that prevented the hydrogenated DLC films from wear, resulting in the increasing of friction coefficient with gas pressure. Graphical abstract Unlabelled Image Highlights • The friction coefficient of hydrogenated DLC film increased with the amount of isobutane, yet the wear remained low. • The experimental results were supported by ab initio calculations and mathematical models. • Model studies showed that the physisorbed isobutane molecules dominated the tribological behavior of hydrogenated DLC film. [ABSTRACT FROM AUTHOR]

Highlights • Unsteady cryogenic cavitation under fluctuating conditions were numerically studied. • Inlet pressures were set as sine functions with different amplitudes and frequencies. • Cavitation process shows a periodic change and is promoted by pressure fluctuations. Abstract Liquid nitrogen spray cooling can achieve an excellent cooling performance in a cryogenic wind tunnel which can simulate supersonic flows with both high Reynolds number and Mach number for aerodynamic tests. However, the fluctuating flow of a liquid nitrogen supply system can lead to the fluctuation of the injection pressure which induces unsteady cavitation and makes it difficult to control the cooling and high-precision temperature in the cryogenic wind tunnel. To understand the characteristics of the unsteady cavitation in fluctuating flow, we developed the numerical models of liquid nitrogen cavitating flow through the spray nozzles. Sine functions are normally used to simulate the fluctuating inlet pressure, and the effects of the fluctuation amplitude and frequency on the cavitation processes are studied under different inlet temperatures. It is found that the cavitation changes periodically and is generally promoted by the pressure fluctuation. The increase of the frequency can slightly suppress the cavitation while the increase of the amplitude can promote the cavitation. The effects of amplitude and frequency are enhanced under a higher inlet temperature. These findings could benefit the design of cryogenic spray cooling systems in cryogenic wind tunnels. [ABSTRACT FROM AUTHOR]

We investigate the effect of liquid properties and surface supercooling on the spreading dynamics of an impact binary ethylene-glycol and ethanol droplet. Surface supercooling and solution concentration, affecting the physical properties of a droplet, jointly determine the maximum spreading factor. At a high concentration of ethylene-glycol, the maximum spreading factor decreases with surface supercooling. At a low concentration of ethylene-glycol, the maximum spreading factor decreases and then increases with surface supercooling. The relation between the maximum spreading factor and surface supercooling is resulting from the opposite surface-supercooling-dependencies of the maximum internal spreading factor and the dimensionless fingering length. The maximum spreading factor decreases with the ethylene-glycol concentration due to increased liquid surface tension and viscosity. A new model of the maximum spreading factor, taking into account the effect of surface cooling in viscous dissipation, is proposed based on energy conservation, which optimizes the prediction of spreading of an impact droplet on a surface with different supercooling degrees. • Phase diagram of the impact regimes of a binary ethylene-glycol and ethanol droplet impacting on a supercooled surface is highlighted. • The effect of solution concentration on the relation of droplet spreading with surface supercooling is illustrated. • A new model of the maximum spreading factor involving surface supercooling degree is proposed. [ABSTRACT FROM AUTHOR]

The two-phase flow boiling characteristics of liquid nitrogen (LN 2 ) in horizontal circular mini-tubes were experimentally studied. Experiments were performed in a wide range of flow conditions, e.g. inlet pressure from 0.17 to 0.35 MPa, mass flux from 140 to 330 kg/m 2 s, heat flux from 0.5 to 69.4 kW/m 2 and tube diameters of 2.92 mm and 3.96 mm. The influences of mass flux, heat flux, and inlet pressure on the pressure drop were discussed. The results indicated that the pressure drop increases with the increasing mass flux and heat flux but decreases with the increasing inlet pressure. But the influence of heat flux on the frictional pressure drop of LN 2 was weaker than mass flux and inlet pressure. The frictional pressure drop of two-phase flow of LN 2 was compared with homogeneous model and several semi-empirical correlations. An improved correlation based on the Lockhart-Martinelli model, which used coefficient C as a function of Reynolds number and Weber number was proposed. [ABSTRACT FROM AUTHOR]

The two-phase heat transfer of saturated liquid nitrogen (LN 2 ) flow boiling in a horizontal corrugated tube was experimentally studied. The experiments were conducted at different inlet pressures of 0.180–0.461 MPa and mass fluxes of 163.1–257.1 kg m −2 s −1 under a wide range of heat flux of 16,000–40,000 W m −2 . The flow pattern was identified to be unstratified flow according to the circumferential distributions of heat transfer temperature differences. Two heat transfer regimes were observed in the present experiment: the nucleate boiling dominated heat transfer and the convective evaporation dominated heat transfer. Due to the thinning of the liquid film at the tube inner surface caused by helical fin, nucleation suppression and convection augmentation were observed and the variation of the circumferential average HTC with the flow parameters became complex depending on the relative importance of the two heat transfer mechanisms. The effects of heat flux, vapor quality, inlet pressure and mass flux on the circumferential average heat transfer coefficient (HTC) are discussed. The results show that the nucleate boiling heat transfer is enhanced with the increase of heat flux, while the convective evaporation is enhanced with the increase of mass flux and vapor quality, and the decrease of pressure. In order to improve the prediction of HTCs, the Klimenko correlation for cryogenic fluids are included in an additive model. Based on the experimental data of circumferential average heat transfer coefficients, the parameterization of the additive model including the convective and nucleate boiling components was obtained for the LN 2 saturated flow boiling in the corrugated tube. Compared to the Klimenko correlation for the flow boiling of cryogenic fluids with a fully wetted perimeter in smooth tubes, the proposed parameterization of the additive model improves the prediction of HTCs in the convective evaporation dominated regime. [ABSTRACT FROM AUTHOR]