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In this paper we derive several explicit results on one special sticky diffusion process which is constructed as a time-changed version of a diffusion with no sticky points. A theorem concerning the process-related Green operators defined on some nonnegative piecewise continuous functions is provided. Then, based on this theorem, we explore the distributional properties of the sticky diffusion. A financial application is presented where we compute the value of the European vanilla call option written on the underlying with sticky price dynamics. [ABSTRACT FROM AUTHOR]

Highlights • Murray's law of tree-like rectangular microchannel network is reexamined. • Effect of dimensional and structural parameters on the Murray's law are investigated. • Convective heat transfer of a tree-like rectangular microchannel heat sink is studied. Abstract The present work theoretically and numerically reexamines the Murray's law to design a tree-like rectangular microchannel network with constant microchannel height under the constraint of constant total channel volume, and investigates effects of the dimensional and structural parameters of the tree-like network on the optimal width ratio and optimal hydraulic diameter ratio of rectangular microchannels at two successive branching levels to achieve a minimum hydraulic resistance. The results show that the optimal hydraulic diameter ratio of the tree-like rectangular microchannel network does not follow the conventional Murray's law. Both the optimal width ratio and the optimal hydraulic diameter ratio to achieve a minimum hydraulic resistance strongly depend on the dimensional and structural parameters including rectangular channel height H , total channel volume V , channel length ratio γ , channel length at the initial branching level L 0 , branching number N and branching level m of the tree-like network. Additionally, the present work finds that the average convective heat transfer coefficient of a heat sink with an elementary T-shaped tree-like rectangular liquid-cooling microchannel network with the constant channel height increases with both the increasing width ratio of microchannels at two successive branching levels and the increasing channel height. [ABSTRACT FROM AUTHOR]

In this paper, we study option prices under a feasible threshold diffusion model subject to jump-to-default risk where the default intensity takes a negative power of the underlying stock price. The model incorporates the regime switches endogenously by assuming the volatility to shift from one regime to another when the stock price crosses the pre-specified threshold level. This threshold can be understood as the psychological price barrier. Using the probabilistic approach, we obtain the Laplace-transform-based analytical solutions to the pricing problem of European vanilla options. Numerical analysis in the end examines the option-related quantities using the derived results and shows the impact of jump-to-default risk and threshold effect. [ABSTRACT FROM AUTHOR]

Tetracycline (TCN) is a typical antibiotic with ecological toxicity, which is easy to cause bacterial drug resistance. Single-atom catalysts have a broad application prospect in the remediation of antibiotic polluted water by activated persulfate (PDS), but its catalytic properties are limited because of its high surface energy and easy aggregation. Therefore, in our manuscript, a novel nitrogen doped magnetic graphene oxide confined Fe-Co dual single-atom catalyst (Fe/Co(1:1) (S) -NMGO) was prepared by one-step molten salt assisted high temperature pyrolysis. XPS and AC-HAADF-STEM analysis indicated single-atom Fe and Co existed. Fe and Co atoms were bound to the material mainly through coordination with pyridinic N and pyrrolic N. While single-atom Fe and Co were simultaneously introduced into the modified materials, the removal rate of TCN reached 93.1%, implying the significant synergistic effect of single-atom Fe and Co on TCN removal. Molten salt assisted high-temperature pyrolysis significantly improved the TCN degradation rate. In addition, this research showed that the existence of magnetite nanoparticles was beneficial to improve the separation performance of the single-atom catalysts as well as the catalytic performance. At the same time, the effects of some key parameters (Fe/Co molar ratio, catalyst dosage, PDS dosage, initial pH, coexisting anions and humic acids) on TCN degradation in Fe/Co(1:1) (S) -NMGO/PDS system were also investigated. The catalytic potential in actual water and regeneration performance of the material were also evaluated. The possible activation mechanism and degradation pathway of TCN were proposed. These findings will provide important reference for the future design and application of single-atom-involved catalysts. [Display omitted] • Fe/Co dual single-atom catalyst was prepared by molten salt assisted pyrolysis. • Molten salts could provide a high polarity environment to destroy metal-metal bond. • Single Fe and Co atoms anchored on NMGO are verified by AC-HAADF-STEM. • TCN removal rate in this system could reach 93% at low catalyzer and PDS dosage. • Free radical (SO 4 •− >O 2 •− >HO•) oxidation were the main degradation mechanisms. [ABSTRACT FROM AUTHOR]

The prices of lots of assets have been proved in literature to exhibit special behaviors around psychological barriers, which is an important fact needed to be considered when pricing derivatives. In this paper, we discuss the valuation problem of double barrier options under a volatility regime-switching model where there exist psychological barriers in the prices of underlying assets. The volatility can shift between two regimes, that is to say, when the asset price rises up or falls down through the psychological barrier, the volatility takes two different values. Using the Laplace transform approach, we obtain the price of the double barrier knock-out call option as well as its delta. We also provide the eigenfunction expansion pricing formula and examine the effect of the psychological barrier on the option price and delta, finding that the gamma of the option is discontinuous at such barriers. [ABSTRACT FROM AUTHOR]

To reduce the influence of a sulfate-based starch water-reducing agent on the setting time of cement, a novel starch-based water-reducing agent, namely sulfate-based starch maleic acid monoester (SAMAS), was designed to adjust its hydrophilicity by maleic acid monoester. Gel permeation chromatography, Fourier transform infrared spectroscopy, and 1H NMR nuclear magnetic resonance spectroscopy were used to characterize the prepared SAMAS, while Zeta potential, UV–Vis absorption, X-ray photoelectron spectroscopy, X-ray diffraction, cement paste fluidity, and setting time measurements were conducted to investigate its dispersion performance, retardation performance, adsorption behavior, and mechanism of action. SAMAS exhibited good dispersion performance and did not significantly prolong the setting time of the cement. In addition, the dispersion performance of SAMAS was found to depend mainly on steric hindrance, and its weak retardation performance originated from the hydrophilic regulation of the maleic acid monoester groups, which ensures the normal progress of the cement hydration reaction by hindering the formation of a hydration film. • SAMAS is prepared using a clean and industrializable method. • SAMAS shows excellent dispersion performance and unique weak retarding performance. • Revealed the adsorption characteristics and mechanism of action of SAMAS [ABSTRACT FROM AUTHOR]

This study presents a pricing model for power exchange options, in which the possibility of default by the risky counterparty as well as the arrival of important business information are taken into consideration. The idiosyncratic and common jump components induced by the arrival of business information are subsumed into all asset price processes whose dynamics are correlated with each other. Employing the measure-change technique, we obtain a pricing formula for the values of power exchange options with counterparty risk. At last, based on the derived formula, we numerically analyze the impacts of counterparty risk and jump risk on option prices. © 2016 Wiley Periodicals, Inc. Jrl Fut Mark 37:499-521, 2017 [ABSTRACT FROM AUTHOR]

Isoflurane exposure induces apoptosis in cultured cells and in the developing brain, while the underlying mechanism remains largely unclarified. This study was designed to determine whether the disruption of mitoK-mediated ATP balance was involved in the cytotoxicity of isoflurane. Human neuroglioma cells U251 and 7-day-old mice were treated with isoflurane. A specific mitoK antagonist 5-HD was used, and the cellular ATP levels, NAD/NADH ratios, and mitochondrial transmembrane potential (ΔΨ) were measured. Our data showed that the blockage of mitoK by 5-HD mitigated the isoflurane-induced ΔΨ disruption, reactive oxygen species (ROS) accumulation, and apoptosis in U251 cells. Moreover, we found that the toxic effect of isoflurane was not observed in the first 2-h exposure; instead, the cellular ATP levels and NAD/NADH ratios were markedly increased. The reduction of ATP levels and NAD/NADH ratios was only detected after this initial phase. This dynamical effect of isoflurane was blocked by 5-HD. In contrast, a ROS scavenger NAC sustained the isoflurane-induced ATP elevation. Similar results were observed in animal studies. And again, 5-HD attenuated isoflurane-induced cognitive disorders in the Intellicage test, a system that assesses place learning behavior in a social environment. Our study uncovered a potential mechanism underlying isoflurane's toxicity with a therapeutic future. [ABSTRACT FROM AUTHOR]

• Curcumin protected against cachectic weight loss in C26 tumor-bearing mice. • Curcumin alleviated cancer cachexia-associated adipocyte atrophy and lipid degradation. • The protective effects of curcumin on cachectic fat loss are mediated by the cAMP/PKA/CREB signaling pathway. Cachexia is a multifactorial debilitating syndrome that is responsible for 22% of mortality among cancer patients, and there are no effective therapeutic agents available. Curcumin, a polyphenolic compound derived from the plant turmeric, has been shown to have anti-inflammatory, antioxidant, anti-autophagic, and antitumor activities. However, its function in cancer cachexia remains largely unexplored. This study aimed to elucidate the mechanisms by which curcumin improves adipose atrophy in cancer cachexia. C26 tumor-bearing BALB/c mice and β3-adrenoceptor agonist CL316243 stimulated BALB/c mice were used to observe the therapeutic effects of curcumin on the lipid degradation of cancer cachexia in vivo. The effects of curcumin in vitro were examined using mature 3T3-L1 adipocytes treated with a conditioned medium of C26 tumor cells or CL316243. Mice with C26 tumors and cachexia were protected from weight loss and adipose atrophy by curcumin (50 mg/kg, i.g.). Curcumin significantly reduced serum levels of free fatty acids and increased triglyceride levels. In addition, curcumin significantly inhibited PKA and CREB activation in the adipose tissue of cancer cachectic mice. Curcumin also ameliorated CL316243-induced adipose atrophy and inhibited hormone-mediated PKA and CREB activation in mice. Moreover, the lipid droplet degradation induced by C26 tumor cell conditioned medium in mature 3T3-L1 adipocytes was ameliorated by curcumin (20 µM) treatment. Curcumin also improved the lipid droplet degradation of mature 3T3-L1 adipocytes induced by CL316243. Curcumin might be expected to be a therapeutic supplement for cancer cachexia patients, primarily through inhibiting adipose tissue loss via the cAMP/PKA/CREB signaling pathway. [Display omitted]. [ABSTRACT FROM AUTHOR]

Epidemiological studies have indicated that exposure to ambient air-borne fine particulate matter (PM2.5) is associated with many cardiopulmonary diseases; however, the underlying pathological mechanisms of PM2.5-induced lung injury remain unknown. In this study, we aimed to assess the impact of acute or prolonged exposure to water-insoluble fractions of PM2.5 (PM2.5 particulate) on lung injury and its molecular mechanisms. Balb/c mice were randomly exposed to PM2.5 once (acute exposure) or once every three days for a total of 6 times (prolonged exposure). Lung, BALF and blood samples were collected, and pulmonary pathophysiological alterations were analyzed. Nrf2 knockout mice were adapted to assess the involvement of Nrf2 in lung injury, and transcriptomic analysis was performed to delineate the mechanisms. Through transcriptomic analysis and validation of Nrf2 knockout mice, we found that acute exposure to PM2.5 insoluble particulates induced neutrophil infiltration-mediated airway inflammation, whereas prolonged exposure to PM2.5 insoluble particulate triggered lung fibrosis by decreasing the transcriptional activity of Nrf2, which resulted in the downregulated expression of antioxidant-related genes. In response to secondary LPS exposure, prolonged PM2.5 exposure induced more severe lung injury, indicating that prolonged PM2.5 exposure induced Nrf2 inhibition weakened its antioxidative defense capacity against oxidative stress injury, leading to the formation of pulmonary fibrosis and increasing its susceptibility to secondary bacterial infection. [Display omitted] • Acute exposure to PM2.5 induced neutrophil mediated airway inflammation. • Prolonged exposure to PM2.5 induced lung fibrosis. • Reduced antioxidant-related genes expression was found after PM2.5 exposure. • Nrf2 knockout mice exhibit increased pulmonary fibrosis after PM2.5 exposure. • PM2.5 exposure increased the susceptibility for secondary bacterial infection. [ABSTRACT FROM AUTHOR]