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Friction has been considered to mediate physiological activities of cells, however, the biological friction between a single cell and its ligand-bound surface has not been thoroughly explored. Herein, we established a friction model for single cells based on an atomic force microscopy (AFM) combined with an inverted fluorescence microscopy (IFM) to study the friction between a highly sensitive platelet and fibrinogen-coated surface. The study revealed that the friction between the platelet and fibrinogen-coated tip is mainly influenced by specific ligand–receptor interaction. Further, we modeled the biological friction, which consists of specific interaction, non-specific interaction, and mechanical effect. Besides, the results suggested that the velocity can also affect specific ligand–receptor interactions, resulting in the friction change and platelet adhesion to fibrinogen surfaces. The study built a friction model between a single cell and its ligand-bound surface and provided a potential method to study the biological friction by the combination of AFM and IFM.

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A novel trench-assisted dual-mode multi-core fiber with large-mode-field-area is proposed. The structure consists of 17 conventional cores and two air holes according to a regular hexagon, which can realize strict dual-mode transmission. The structural parameters’ effect on mode transmission characteristics, mode-field-area, and bending loss are analyzed systematically. By optimizing the structural parameters, the mode-field-area of the fundamental mode can reach ${2100.619}\;{{\unicode{x00B5}{\rm m}}^2}$. The introduction of the trench with a lower refractive index than cladding can reduce the bending loss to ${9.88} \times {{10}^{- 4}}\;{\rm dB}/{\rm m}$ when the bending radius is 2.3 cm. Besides, the structural design is flexible, and the manufacturing process is simple, which has broad application prospects.

Background: Tibetan medicine Gaoyuan’an capsule (GYAC) is widely used to prevent pulmonary edema at high altitude, but the specific mechanism has not been explored. In this study, we analyzed the mechanism of GYAC in hypoxia tolerance, and provided a new idea for the prevention and treatment of altitude disease. Methods: The effective components and corresponding targets of GYAC were screened out by the Chinese herbal medicine network database, and the key targets of hypoxia tolerance were retrieved by Genecards, OMIM and PubMed database. Cytoscape 3.7.2 was used to construct GYAC ingredient-target-hypoxia tolerance-related target network. GO function annotation and KEGG enrichment analysis were performed to predict the pathways in which target genes may be involved, and molecular docking was used to verify the binding ability of the compound to target genes. In vitro, the above results were further verified by molecular experiment. Results: We found that GYAC can improve hypoxia tolerance by regulating various target genes, including IL6, IFNG, etc. The main regulatory pathways were HIF-1 signaling pathway. Molecular docking showed that the affinity between luteolin and target genes (IL6, IFNG) were better. In vitro, we observed that hypoxia can inhibit cell viability and promote apoptosis of H9C2 cell. And hypoxia can promote the expression of LDH. After the addition of luteolin, the decrease of cell viability, the increase of cell apoptosis, LDH release and the decrease of mitochondrial membrane potential were inhibited. Besides, inflammatory related factors (IL-6, IL-10, IL-2, IFNG and VEGFA) expression were also inhibited hypoxic cell models. Conclusions: The results of network pharmacology and molecular docking showed that luteolin, a monomeric component of GYAC, played a role in hypoxia tolerance through a variety of target genes, such as IL6, IFNG. What’s more, we have discovered that luteolin can reduce the inflammatory response in cardiac myocytes, thereby alleviating mitochondrial damage, and ultimately enhancing the hypoxia tolerance of H9C2 cardiomyocytes.

Natural gas production from shale formations involves highly complex geological features consisting of fractures that are embedded spatially-distributed in a matrix made of organic and inorganic materials. In this paper, we develop a coupled multiscale and multi-continuum approach for simulating gas transport in the shale formation. The multiscale method allowed us to capture detailed interactions between the fractures and the background. For the fine-scale heterogeneities involving organic and inorganic materials distribution in the matrix, we use a dual-continuum approach. The matrix is coupled to the fractures by use of the Generalized Multiscale Finite Element Method (GMsFEM). In our previous work (Akkutlu et al., 2016), we used a single-continuum background coupled to the fracture network. This paper presents a significant extension and considers dual-continuum media as a background. GMsFEM systematically identifies the fracture networks by constructing corresponding multiscale basis functions. GMsFEM also accurately represents the fractures interacting with the background media. Moreover, GMsFEM can handle any spatial fracture distributions and thus, it avoids the limitations of the multi-continuum approaches. Results show that the proposed numerical approach can accurately capture the interactions between the fractures and the multi-continuum model using a few multiscale basis functions.

Background: Target therapy has been one of the important strategies in new drug discovery and the resulting drug resistance has also been a serious problem for concern. At the same time, there are several cancer genes or pathways operating within a given cancer. Given these two things, the combination therapy will be needed for optimal therapeutic effect. Objective: Camptothecin and norcantharidin were thus chosen to construct a dual anticancer drugs assemblies mainly because CPT was the DNA-topoisomerase I inhibitor and norcantharidin could also suppress the cancer cell growth by inhibiting protein phosphatase. The designed conjugate of camptothecin and norcantharidin linked by alanine was expected to have dual target drug properties. Methods: EDCI/DMAP was chosen as a coupling agent for the coupling of CPT with substituted norcantharidin derivatives and CCK-8 method was used to test the cytotoxicity and intensity on human hepatoma cell line HepG2. Two kinds of enzymes, Top I and CDC 25B were selected to screen the binding affinity in molecular level. Results: Nine of dual targets camptothecin derivatives were smoothly synthesized by twice coupling in the condition of EDCI/DMAP in moderate yield. All of the synthesized compounds were characterized by 1HNMR and 13CNMR spectrum and exhibited strong potent inhibition against Hep G2, SW480, BGC803, and PANC-1 cell line in vitro. The newly synthesized camptothecin compounds, such as 3j and 3i have strengthened inhibition activity compared to camptothecin and norcantharidin. Conclusion: We have successfully synthesized a series of novel camptothecin derivatives constructed from three components of camptothecin, alanine and norcantharidin. These compounds not only preserved strong activity against several cancer cell lines in vitro, but also exhibited potential binding affinity to target Top I and CDC 25B. Therefore, these conjugates linked by alanine could suppress cancer cell growth by inhibiting Top I and protein phosphatase simultaneously, which makes it much valuable as a novel bi-functional target drug candidate to develop in vivo.

In this study, coconutshell-, coal-, and wood-based activated carbon were selected as the adsorbents for NO adsorption. KOH and transition metal oxides (CuO, FeOx, and NiO) were further adopted to improve the NO removal efficiency and adsorption capacity at ambient temperature. The results showed that CSAC-KOH(3)-NiO(10)adsorbents (coconut shell based activated carbon modified by 3% KOH and then 10% NiO) achieved the highest removal efficiency of NO (above 95.6%) and adsorption capacity (5.26 mg/g) within 60 min. XPS and NO-TPD results indicated that the increase of −C–O and OH–/Ox–species might be the reasons for good removal efficiency of NO over CSAC-KOH, while the increase of OH-/Ox–and lattice oxygen (O2–in Ni–O) species is the reason for the CSAC-KOH-NiO sample. The medium sites of the active adsorbed oxygen (Ox–) species and strong sites of lattice oxygen are the major adsorption sites on the surface of CSAC-KOH-NiO. The possible NO adsorption process were proposed that the main nitrite species (−NO2) might be generated by lattice oxygen (O2–) in Ni–O sites with the stimulation effects of active oxygen (Ox–or/and [O]), while NO–and – NO3species were generated from −C—C, −C═C, and −C═O sites.

Rapid detection of foodborne pathogens is crucial to prevent the outbreaks of foodborne diseases. In this work, we proposed a novel microfluidic biosensor based on magnetorheological elastomer (MRE) and smartphone. First, micropump and microvalves were constructed by deforming the MRE under magnetic actuation and integrated into the microfluidic biosensor for fluidic control. Then, the micropump was used to deliver immune porous gold@platinum nanocatalysts (Au@PtNCs), bacterial sample, and immunomagnetic nanoparticles (MNPs) into a micromixer, where they were mixed, incubated and magnetically separated to obtain the Au@PtNC-bacteria-MNP complexes. After 3,3′,5,5′-tetramethylbenzidine and hydrogen peroxide were injected and catalyzed by the Au@PtNCs, smartphone was used to measure the color of the catalysate for quantitative analysis of target bacteria. Under optimal conditions, this biosensor could detect Salmonella typhimuriumquantitatively and automatically in 1 h with a linear detection range of 8.0 × 101CFU/mL to 8.0 × 104CFU/mL and a detection limit of 62 CFU/mL. The microfluidic biosensor was compact in size, simple to use, and efficient for detection, and might be used for in-field screening of foodborne pathogens to prevent food poisoning.

More than half of oil remains in the reservoir pores after water flooding. A microscopic visualised physical model under high temperature and pressure was created to simulate a reservoir pore network. It is an efficient way to study the formation and distribution of microscopic remaining oil which can enhance oil recovery. Displacement mechanisms were researched for CO2/water alternative flooding (CO2-WAG). The remaining oil morphology and migration characteristics were directly observed and analysed. The distribution of the remaining oil of models in different flooding stages was quantitatively obtained by grey images processing technology. Comparing the distribution of different occurrences of microscopic remaining oil, the multiphase fluid transport characteristics in the experimental porous media is described. Experimental results show that the recovery efficiency under the CO2-oil miscible state can be enhanced 5.75% more than the immiscible state. There exist four types of remaining oil after CO2-WAG with different effects, namely: 1) clusters; 2) columnar; 3) membrane; 4) blind-end remaining oil. Miscible CO2-WAG could efficiently improve oil recovery of cluster, column, and membrane types of remaining oil. Immiscible CO2-WAG only caused an obvious recovery improvement for the cluster type of remaining oil. In order for CO2-WAG flooding to be used to improve oil recovery most efficiently, the occurrence state and distributions of remaining oil should first be considered. [Received: June 23, 2015; Accepted: March 1, 2016]

The nitrile-containing insecticides sulfoxaflor, flonicamid, thiacloprid, and acetamiprid are used widely in agriculture, polluting the environment and harming animals. The Co2+-dependent enzyme nitrile hydratase (NHase) is a powerful tool for the degradation of nitrile-containing insecticides. Here, the NHase activities of Escherichia colipET28a-PsNHase, harboring Pseudomonas stutzeriCGMCC 22915 (Ps) NHase gene, and E. colipET28a-PsNHase-PsCbiM, harboring genes of PsNHase and a cobalt transporter PsCbiM, were compared. The presence of PsCbiM promoted PsNHase activity. E. colipET28a-PsNHase-PsCbiM was immobilized using calcium alginate, which increased the tolerance of its NHase to acidic, alkaline, and high-temperature environments. Immobilized E. colipET28a-PsNHase-PsCbiM was applied to degrade sulfoxaflor, flonicamid, thiacloprid, and acetamiprid. These insecticides were both substrates and inhibitors of immobilized E. colipET28a-PsNHase-PsCbiM. Substrate inhibition model assays showed that the optimum initial concentrations of sulfoxaflor, flonicamid, thiacloprid, and acetamiprid for degradation by immobilized cells were 455.01, 195.50, 139.20, and 410.26 μmol/L, respectively. Degradation of nitrile-containing insecticides by immobilized engineered E. colicells was reported here for the first time. This study provides a novel and excellent bioremediation agent for treatment of wastewater contaminated with nitrile-containing insecticides.

Liquid infused surfaces (LIS) hold remarkable potential in anticoagulation. However, liquid loss of LIS in the bloodstream remains a challenge toward its clinical application. Here, micronano hierarchy structures are obtained on the titanium alloy substrate by regulating the microspheres’ distribution. When the gap between the microspheres is smaller than the diameter of the red blood cell (RBC), the LIS is more stable under the blood wash and presents a better anticoagulation performance. The proper interval is found to prevent the RBCs from entering the gap and remove the liquid on the surface. The retained thickness of the liquid film is measured by the atomic force microscopy (AFM) technique. The LIS is applied on the front guide vane of an artificial heart pump and exhibits significant improvement on anticoagulation in the blood circulation in vitro for 25 h. The techniques and findings can be used to optimize the anticoagulation performance of LIS-related biomedical implant devices.

Steam reforming (SR) of single model molecules (acetone, butanol, and ethanol) and a specific mixture (butanol/acetone/ethanol = 6/3/1, mass ratio) assumed as a model of biobutanol raw mixture has been researched over mesoporous Nix/MgO catalysts (xrepresented nickel mole percent in Ni–Mg) at 673–873 K. The result showed reactant conversion at lower temperatures allowed ranking the three single-molecule compounds as the function of SR activity as follows: ethanol > acetone > butanol. The catalytic performance of mesoporous Ni0.12/MgO catalyst with lower Ni component containing enough active sites outperformed that of mesoporous Ni0.16/MgO catalyst which was more inclined to sinter in all SR tests of single-component compounds except at 673 K. On the contrary, the catalytic behavior of Ni0.16/MgO (richer in nickel) was superior to that of Ni0.12/MgO catalyst in SR of multicomponent compounds. Moreover, in acetone–butanol–ethanol steam reforming (ABESR), SR of ethanol suffered competition from acetone and butanol, suppressing ethanol molecule access to the limited active sites of the catalyst. As a consequence, the conversion of ethanol in SR of multicomponent compounds decreased compared to that in SR of pure ethanol.

Foam stabilized by a surfactant has been used successfully for mobility control during enhanced oil recovery processes, but the stability of the foam limits its application. Aqueous foams prepared from dispersions of partially hydrophobic silicon dioxide (SiO2) nanoparticles and sodium dodecyl sulfate (SDS) anionic surfactant were studied and the injection behavior of foams stabilized by a solution of SDS or dispersion of SiO2/SDS were analyzed for comparison. Foam stability increased with increasing nanoparticle concentration although the feasibility of producing a foam (foamability) followed the opposite trend. The surface tension and interfacial dilatational rheological properties were affected by the addition of SiO2nanoparticles. When 0.05 wt % SiO2was added to the solution of SDS, the system's dilatational elasticity increased significantly, but not the dilatational viscosity. The sweep efficiency to dead end was very small, and the SiO2/SDS foam could displace more residual oil in the dead end than that in the SDS foam. The differential pressure could increase to 0.58 MPa when SDS foam was injected, but for the SiO2/SDS foam it could increase to 1.7 MPa. The SiO2/SDS foam exhibited better profile control performance than that of the SDS foam. When subsequent water was injected for 3.5 pore volumes, the flow rate of the high‐permeability sand pack could still be maintained at 1.0 mL min−1, which suggested that the SiO2/SDS foam had a better resistance to water flushing. Additionally, the foam volume should also be considered, especially for a SiO2concentration of >1.5 wt %. SiO2/SDS foam can reduce the residual oil saturation clearly, and the enhanced oil recovery and final oil recovery can reach 36.90 and 69.57 %, respectively. Flushing out the last drop: This study focuses on the properties of foams stabilized by partially hydrophobic nanoparticles and the anionic surfactant sodium dodecyl sulfate (SDS). The foam stability increases with increasing nanoparticle concentration, although its feasibility to produce a foam (foamability) follows the opposite trend. It is believed that improved foam stability, dilatational viscoelasticity, and efficient oil recovery from dead‐end pores may be the main factors that result in high oil recovery levels.

Foam flooding is a promising technique for enhancing oil recovery, but the foam instability limits its application. This study investigates the properties of foam stabilized by silica (SiO2) nanoparticles combined with hexylamine. Surface dilational rheology, contact angle, and adsorption measurements have been performed and correlated with the foam stability. The results show that the SiO2/hexylamine dispersion induces a synergistic effect on the foam stability at intermediate hexylamine concentrations. The most stable foam was obtained with the most hydrophobic particles. The dilational viscoelasticity and the adsorption amount followed the same trend as that of foam stability. As a plugging agent, the SiO2/hexylamine foam could block the core with the maximum pressure peak at approximately 0.85 MPa. Moreover, our results indicate that the foam stability, dilational viscoelasticity, and roughness of the bubble surface together might contribute to better plugging performance in porous media. Nanoparticles Stabilized Foam: The properties of a foam stabilized by SiO2nanoparticles combined with hexylamine are presented in this work for use in enhanced oil recovery. A four‐region model, based on the adsorption behavior of surfactant on particles, is used to explain different phase behaviors of the SiO2/hexylamine dispersion. The flooding experiments show that the particle‐stabilized foams have an effective plugging performance in porous media.

To report a rare liveborn case with a giant, septated, chest wall lymphangioma that underwent prenatal expectation treatment.

Deep desulfurization of a high-sulfur jet fuel (for fuel cell applications) was achieved by adsorption with -complexation sorbents. The total sulfur content of JP-5 jet fuel was removed from 1172 ppmw S to below 1 ppmw S. The following sorbents were prepared and tested:  CuCl supported on activated carbon (CuCl/AC), PdCl2/AC, PdCl2/Al2O3, and Cu(I)−Y zeolite. Comparison of these sorbents as well as other known sorbents showed that PdCl2/AC had the highest sulfur selectivity and capacity. It was found that significant breakthrough occurred at about 6.0 mL/g for desulfurization of JP-5 by PdCl2/AC. Ab initio molecular orbital computation was performed for the bond energies between different sulfur molecules and these sorbents. For methylated benzothiophene, the main sulfur molecules in jet fuels, the bond energies (and the separation factors for organosulfur/benzene) followed the order PdCl2> CuCl > Cu−Y. This result was in agreement with the experimental breakthrough data. The spent PdCl2/AC was regenerated with benzene in a static system, and the regenerated sorbent was tested for reuse. The results showed that ∼74 wt % adsorbed sulfur could be desorbed and 72% of the sulfur capacity could be recovered for reuse.