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The dissolution behaviour of three corn starches, including corn starch (CS), high amylose corn starch (HACS) and waxy corn starch (WCS) with different amylose content in 1-allyl-3-methylimidazolium chloride ([AMIM]Cl) and 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) were studied by comparing their dissolution state in ionic liquids (ILs). Further, the structural and thermal properties of the regenerated starch were analyzed. WCS with the lowest amylose content had the fastest dissolution rate, the most extensive structural damage, and the lowest solubility and required the maximum energy for dissolution. In the process of dissolution-regeneration, the A-type crystalline structure of WCS and CS was completely destroyed and transformed into an amorphous structure, while the B-type crystalline structure of HACS transformed into an ordered V-shaped structure. And the thermal stability of starch was improved after dissolution-regeneration in ILs. Among the two kinds of ILs, [AMIM] Cl had a better ability to dissolve starch, causing minor damage to the starch.

In this paper, CuOx@Ag/CeO2 catalysts were synthesized by simple wet-chemical method and equal volume impregnation method. The obtained catalysts were subjected to soot temperature programmed oxidation (soot-TPO) activity tests and were further characterized by various techniques such as X-ray diffraction (XRD), transmission electron microscopy/high-resolution transmission electron microscopy (TEM/HR-TEM), N2 physisorption, X-ray photoelectron spectroscopy (XPS) and H2- temperature programmed reduction (H2-TPR). The results show that CuOx@Ag/CeO2 synthesized presents well controlled core-shell structures, with nano-cube like Cu2O as the core and Ag decorated polycrystalline CeO2 grafting layers as the shell. Such core-shell structured CuOx@Ag/CeO2 can successfully construct a secondary oxygen delivery channel (CuOx → CeO2 → Ag) to effectively transfer bulk oxygen of the catalyst to the soot, resulting in its excellent soot oxidation activity compared to CuOx@CeO2. The potential benefiting effect by Ag introduction over Cu@Ag/Ce can be concluded as: (i) pumping lattice oxygen and accelerating gaseous O2 dissociation to generate significantly increased active surface oxygen content; (ii) modulating a moderate surface oxygen vacancies concentration to maintain more highly active O2– species.

In order to save energy consumption, improve network performance and prolong the life cycle of communication network, a reasonable relay selection algorithm for energy collection wireless sensor networks is proposed. Firstly, taking solar wireless sensor network as an example, the energy consumption and solar energy state of sensor nodes are mathematically analyzed. Then, the cooperation probability is optimized with the interruption probability threshold as the constraint, and the relay nodes participating in the cooperative transmission are controlled to save the energy of cooperative transmission in the system. According to the solar energy status, network energy balance, signal-to-noise ratio and outage probability of the relay node, a multi criteria relay selection strategy is adopted to select the optimal node. Compared with the comparison algorithm, this algorithm can save at least 47.1% power consumption and prolong the network lifetime by 25.9%.

Hypothesis Droplet spreading on surfaces is a ubiquitous phenomenon in nature and is relevant with a wide range of applications. In practical scenarios, surfaces are usually associated with certain levels of vibration. Although vertical or horizontal modes of vibration have been used to promote droplet dewetting, bouncing from immiscible medium, directional transport, etc., a quantitative understanding of how external vibration mediates the droplet behaviors remains to be revealed. Methods We studied droplets impacting on stationary and vibratory surfaces, respectively. In analogy to the Weber number We = ρ U i 2 D 0 / γ , we define the vibration Weber number We * = ρ U v 2 D 0 / γ to quantitively analyze the vibration-induced dynamic pressure on droplet behaviors on vibratory surfaces, where ρ , γ , D 0 , U i and U v are liquid density, surface tension, initial droplet diameter, impact velocity of the droplet, and velocity amplitude of vibration, respectively. Findings We demonstrate that the effect of vibration on promoting droplet spreading can be captured by a new scaling number expressed as We * / [ We 1\2 sin ( θ/2 ) ] , leading to (Dm − Dm0)/Dm0 ∝ We * / [ We 1\2 sin ( θ/2 ) ] , where θ is the contact angle, and Dm0 and Dm are the maximum diameter of the droplet on stationary and vibratory surfaces, respectively. The scaling number illustrates the relative importance of vibration-induced dynamic pressure compared to inertial force and surface tension. Together with other well-established non-dimensional numbers, this scaling number provides a new dimension and framework for understanding and controlling droplet dynamics. Our findings can also find applications such as improving the power generation efficiency, intensifying the deposition of paint, and enhancing the heat transfer of droplets.

In this paper, we consider the desingularization of multiscale solutions to 2D steady incompressible Euler equations. When the background flow ψ 0 is nontrivial, we construct a family of solutions which has nonzero vorticity in small neighborhoods of a given collection of points. One prescribed set of points comprises minimizers of the Kirchhoff-Routh function, while another part of points is on the boundary determined by both ψ 0 and Green's function. Moreover, heights and circulation of solutions have two kinds of scale. We prove the results by considering maximization problem for the vorticity and analyzing the asymptotic behavior of the maximizers.

Comorbid chronic pain and depression are increasingly becoming a concerning public problem, but the underlying mechanisms remain unclear. Here, we demonstrate that pain-related depression-like behaviors are induced in a rat model of chronic constriction injury (CCI). Using this model, we found that chronic neuropathic pain decreased the activity and expression of sirtuin 1 (SIRT1, an NAD+-dependent deacetylase) in the central nucleus of the amygdala (CeA). In addition, the pharmacologic activation of SIRT1 in the CeA could alleviate the depression-like behaviors associated with chronic pain while relieving sensory pain. Accordingly, adeno-associated virus (AAV)-mediated SIRT1 overexpression in the CeA produced a positive effect on the easement of chronic pain and comorbid depression. Taken together, these findings highlight the role of SIRT1 in the CeA in chronic pain and depression states and reveal that the upregulation of SIRT1 may be a potential therapy for the treatment of pain-depression comorbidities.

The gas-liquid counter-current flow limitation (CCFL) is closely related to efficient and safety operation of many equipment in industrial cycle. Air-water countercurrent flow experiments were performed in a tube with diameter of 25 mm to understand the triggering mechanism of CCFL. A parallel electrode probe was utilized to measure film thickness whereby the time domain and frequency domain characteristics of liquid film was obtained. The amplitude of the interface wave is small at low liquid flow rate while it becomes large at high liquid flow rate after being disturbed by the airflow. The spectral characteristic curve shows a peak-shaped distribution. The crest exists between 0 and 10 Hz and the amplitude decreases with the frequency increase. The analysis of visual observation and characteristic of film thickness indicate that two flooding mechanisms were identified at low and high liquid flow rate, respectively. At low liquid flow rate, the interfacial waves upward propagation is responsible for the formation of CCFL onset. While flooding at high liquid flow rate takes place as a direct consequence of the liquid bridging in tube due to the turbulent flow pattern. Moreover, it is believed that there is a transition region between the low and high liquid flow rate.

The presence of the blood-brain barrier (BBB) remains a challenge in the treatment of central nervous system (CNS) diseases, as it hinders the infiltration of many therapeutic drugs into the brain parenchyma. Therefore, developing efficacious pharmacological agents that can traverse the BBB is crucial for optimal treatment of diseases of the CNS such as neurodegenerative conditions and brain tumors. Adeno-associated virus (AAV), one of the most promising gene therapy vectors, has been shown to cross the BBB safely and is non-pathogenic in nature and therefore has been utilized for numerous diseases of the CNS. Along with the development of protein engineering techniques such as directed evolution including DNA shuffling, a great number of BBB-crossing AAVs have been developed, that could be systemically injected for therapeutic benefit. In this review, we discuss several feasible approaches to improve transportation of therapeutic agents to the CNS. We also discuss the advantages of using BBB-crossing AAVs, their role as a gene delivery agent and highlight the different types of BBB-AAV vectors that have been developed in order to provide a greater insight into how they can be used in diseases of the CNS.

Anesthesia of neonates with propofol induces persistent behavioral abnormalities in adulthood. Although propofol-triggered apoptosis of neurons in the developing brain may contribute to the development of cognitive deficits, the mechanism of neurotoxicity induced by neonatal exposure to propofol remains unclear. In this study, the effects of neonatal propofol anesthesia on synaptic plasticity and neurocognitive function were investigated. Postnatal day 7 (PND-7) Sprague-Dawley rats were intraperitoneally injected with fat emulsion or 20, 40 or 60 mg/kg propofol for three consecutive days. The expression of brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB) and postsynaptic density protein 95 (PSD-95) in the rat hippocampus at PND-10 and PND-12 was measured by Western blotting. The number of dendritic branches, total dendritic length and dendritic spine density were observed by Golgi-Cox staining 24 h and 72 h after the last propofol administration. Long-term potentiation (LTP) was measured electrophysiologically in hippocampus of PND-60 rats to evaluate the synaptic function. The learning and memory abilities of rats were evaluated by Morris water maze (MWM) experiments, Novel object recognition test (NORT) and Object location test (OLT) at PND-60. Our results showed that neonatal exposure to propofol significantly inhibited the expression of BDNF, TrkB and PSD-95 in the rat hippocampus. The number of dendritic branches, total dendritic length and dendritic spine density of neurons in the rat hippocampus were markedly reduced after neonatal propofol anesthesia. LTP was significantly diminished in hippocampus of PND-60 rats after repeated exposure to propofol in the neonatal period. Morris water maze experiments showed that repeated neonatal exposure to propofol significantly prolonged the escape latency and decreased the time spent in the target quadrant and the number of platform crossings. NORT and OLT showed that repeated neonatal exposure to propofol markedly reduced the Investigation Time for novel object or location. All of the results above indicate that repeated exposure to propofol in the neonatal period can impair hippocampal synaptic plasticity and the recognition function of rats in adulthood.

Group 2 innate lymphoid cells (ILC2s), characterized by secretion of type 2 cytokines, regulate multiple immune responses. ILC2s are found in different tumor tissues, and ILC2-derived interleukin (IL)-4, IL-5, and IL-13 act on the cells in tumor microenvironment to participate in tumor progression. ILC2s are abundant in colorectal cancer (CRC) tissue, but the role of ILC2s in CRC remains unclear. In this study, we found that the percentage of ILC2s was higher in CRC tissue than in the adjacent normal tissue and that these ILC2s were the dominant IL-9-secreting cell-subsets in CRC tissue, as shown by flow cytometry analysis. ILC2s-derived IL-9 could activate CD8+ T cells to inhibit tumor growth, while anti-IL-9 reversed this effect. In vivo experiments showed that neutralizing ILC2s promoted tumor growth, while tumor inhibition occurred by intravenous injection of IL-9. In conclusion, our results demonstrated that ILC2-derived IL-9 could activate CD8+ T cells to promote anti-tumor effects in CRC.

The most stable structures of Ge6M (M = Ge, Al) clusters and reactions of Ge6M clusters with a single water molecule are investigated theoretically by density functional theory (DFT) calculation and reaction pathway search method at the same level. The calculated binding energies of Ge7 and Ge6Al clusters show that the stabilities of two clusters are close. The most stable geometric structures and electronic structures of Ge6M@H2O complex and reaction pathways of Ge6M with a single H2O molecule are predicted. All geometric structures of reactants, intermediate products, final products and transition states are confirmed by frequency analysis. Our results show that both of Ge7 and Ge6Al clusters can completely release H2 from water after a three steps reaction and both reactions are endothermic. The calculated adsorption energies and energy barriers indicate that the dopant Al atom will improve the reactivity between Ge7 cluster and water. The NPA charge of Ge7O and Ge6AlO means both of them can react with another H2O molecule.

Lev/MSNs/n-HA/PU has been proved to be a novel scaffold material to treat bone defect caused by chronic osteomyelitis. We have previously identified that this material can effectively treat chronic osteomyelitis caused by Staphylococcus aureus in vivo. However, the potential mechanisms of antibacterial and osteogenic induction properties remain unclear. Thus, for osteogenesis property, immunohistochemistry, PCR, and Western blot were performed to detect the expression of osteogenic markers. Furthermore, flow cytometry and TUNEL were applied to analyze MC3T3-E1 proliferation and apoptosis. For antibacterial property, the material was co-cultivated with bacteria, bacterial colony forming units was counted and the release time of the effective levofloxacin was assayed by agar disc-diffusion test. Moreover, scanning electron microscope was applied to observe adhesion of bacteria. In terms of osteogenic induction, we found BMSCs adherently grew more prominently on Lev/MSNs/n-HA/PU. Lev/MSNs/n-HA/PU also enhanced the expression of osteogenic markers including OCN and COL1α1, as well as effectively promoted the transition from G1 phase to G2 phase. Furthermore, Lev/MSNs/n-HA/PU could reduce apoptosis of MC3T3-E1. Besides, both Lev/MSNs/n-HA/PU and n-HA/PU materials could inhibit bacterial colonies, while Lev/MSNs/n-HA/PU possessed a stronger antibacterial activities, and lower bacterial adhesion than n-HA/PU. These results illustrated that Lev/MSNs/n-HA/PU composite scaffold possess favorable compatibility in vitro, which induce osteogenic differentiation of MSCs, promote proliferation and differentiation of MC3T3-E1, and inhibit apoptosis. Moreover, clear in vitro antibacterial effect of Lev/MSNs/n-HA/PU was also observed. In summary, this study replenishes the potential of Lev/MSNs/n-HA/PU composite scaffold possess dual functions of anti-infection and enhanced osteogenesis for future clinical application.

Series of Fe/Cu-SSZ-13 catalysts with different Fe loading content were synthesized by simple one-pot strategy. The obtained catalysts were subjected to selective catalytic reduction (SCR) of NOx with NH3 and were characterized by various techniques. The results show that Fe0.63/Cu1.50-SSZ-13 catalyst with proper Fe content exhibits excellent catalytic activity with widest operation temperature window from 160 to 580°C, excellent hydrothermal stability as well as good resistance to sulfur poisoning when compared with Cu-SSZ-13, signifying its great potential for practical applications. Further characterizations reveal that the synthesized Fe/Cu-SSZ-13 catalysts present typical chabazite (CHA) structure with good crystallinity, while isolated Cu2+ and monomeric Fe3+ are revealed as the predominant copper and iron species. At low temperatures, isolated Cu2+ species act as primary active sites for SCR reaction, while monomeric Fe3+ species provide sufficient active sites for sustain the SCR activity at high temperature. Moreover, Fe over doping would lead to the damage of zeolite structure, destruction of isolated Cu2+ site, as well as the formation of highly oxidizing Fe2O3, thus causing deterioration of catalytic performances.

In this article, we construct traveling-rotating helical vortices with small cross-section to the 3D incompressible Euler equations in an infinite pipe, which tend asymptotically to singular helical vortex filament evolved by the binormal curvature flow. The construction is based on studying a general semilinear elliptic problem in divergence form \begin{equation*} \begin{cases} -\varepsilon^2\text{div}(K(x)\nabla u)= (u-q|\ln\varepsilon|)^{p}_+,\ \ &x\in \Omega,\\ u=0,\ \ &x\in\partial \Omega, \end{cases} \end{equation*} for small values of $ \varepsilon. $ Helical vortex solutions concentrating near several helical filaments with polygonal symmetry are also constructed., Comment: 40 pages

In this paper, we are concerned with nonlinear desingularization of steady vortex rings of three-dimensional incompressible Euler fluids. We focus on the case when the vorticity function has a simple discontinuity, which corresponding to a jump in vorticity at the boundary of the cross-section of the vortex ring. Using the vorticity method, we construct a family of steady vortex rings which constitute a desingularization of the classical circular vortex filament in several kinds of domains. The precise localization of the asymptotic singular vortex filament is proved to depend on the circulation and the velocity at far fields of the vortex ring, and the geometry of the domains. Some qualitative and asymptotic properties are also established.

Sulfonamide antibiotics (SAs) are widely used in medicine, animal husbandry and aquaculture, and excessive intake of SAs may pose potential toxicity to organisms. The toxicological mechanisms of two classical SAs, sulfamerazine (SMR) and sulfamethoxazole (SMT), were investigated by molecular docking, DFT and multi-spectroscopic techniques using HSA and BSA as model proteins. The quenching of HSA/BSA endogenous fluorescence by SMR was higher than that by SMT due to the stronger binding effect of the pyrimidine ring on HSA/BSA compared to the oxazole ring, and that result was consistent with that predicted by DFT calculations. Thermodynamic parameters show that the binding of SAs to HSA/BSA is an exothermic process that proceeds spontaneously (ΔG0). Marker competition experiments illustrate that the binding site of SMR/SMT on serum albumin is located in subdomain IIIA. The combination of SAs and HSA/BSA is mainly realized by hydrogen bond and hydrophobic interaction, and the concept is also supported by molecular modeling. The reduced α-helix content of HSA/BSA induced by SMR/SMT indicates a greater stretching of the protein α-helix structure of the SMR/SMT-HSA/BSA. The results could provide useful toxicological information on the hazards of SAs in response to growing concern that SAs may pose a toxic threat to organisms.

Four CeO2–ZrO2 mixed oxides with different morphologies were synthesized using hydrothermal (polyhedra, rods and plates) and coprecipitation method (disordered). Detail structural/physio-chemical characterizations, catalytic activity measurements as well as in situ DRIFTS were conducted on the obtained ceria-zirconia as well as its supported Rh-only TWCs. The CeO2-ZrO2 mixed oxides present different exposed crystal planes and the catalytic performance of Rh/CeO2-ZrO2 is closely related to such different microstructures. Polyhedra shaped CeO2-ZrO2 exhibits increased lattice micro-strain originated from lattice distortion and defects, which can promote the mobility of bulk oxygen species to the surface, resulting in better three-way performance. Disordered Rh/CeO2-ZrO2 catalyst with high surface area and OSC shows wider static operation window, but the surface rhodium species tend to exist as Rh4+ with low redox ability which not favorable for the redox reactions. Besides, the lack of intermediate Rh-(NO)2 and Rh-CN species over disordered Rh/CeO2-ZrO2 based on in situ DRIFTS further reveals its unsatisfactory performance for NOx conversion.

A series of (Ce, Cr)xO2/Nb2O5 catalysts with different (Ce, Cr)xO2 to Nb2O5 mass ratios were synthesized by the deposition-precipitation method for use in deep catalytic oxidation of 1,2-dichloroethane (DCE), which is one of the typical chlorinated volatile organic compound pollutants. The textural properties were characterized by X-ray diffraction, N2 adsorption/desorption isotherms, UV-Raman spectroscopy, and scanning electron microscopy. The surface acidity and the redox properties were characterized by ammonia temperature-programmed desorption and H2 temperature-programmed reduction, respectively. The results show that the addition of a proper amount of (Ce, Cr)xO2 over Nb2O5 significantly improves the intrinsic catalytic activity towards the deep oxidation of DCE, and only a very small amount of C2H3Cl is detected as the byproduct of the oxidation process. Further study reveals the existence of an obvious synergistic effect between Nb2O5, with abundant strong acid sites, and (Ce, Cr)xO2, with strong oxidation sites, as the strong acid sites of Nb2O5 promote the adsorption and dehydrochlorination of DCE, while the strong oxidation sites of (Ce, Cr)xO2 contribute to the deep oxidation of the reactant, intermediates, and byproducts.

Blending with non-starch hydrocolloids is a crucial method to modify the processing properties of native starch. However, few comprehensive studies investigated the effects of inulin on the properties of rice starch (RS). In this research, we used three types of inulin with different degrees of polymerization (DP), namely, short-chain inulin (SI, DP 10), and long-chain inulin (LI, DP > 23), to investigate the effects of inulin on the pasting, thermal, and rheological properties of RS and to provide the foundation for the application of inulin in RS-based food. Inulin addition increased the pasting temperature of RS and decreased all viscosity indices, including the peak, final, breakdown, and Setback viscosities of RS. Compared with LI, SI and MI exerted stronger influence on the viscosity indices of RS. The gelatinization temperature levels of the RS–inulin blends were higher than that of starch alone. The RS and RS–inulin blends exhibited a shear-thinning property, and stress–shear hysteresis loops were observed during shear. Thixotropy followed the order RS > RS-LI > RS-MI > RS-SI. Dynamic viscoelasticity results indicated that the RS and RS–inulin blends displayed weak gel-like behavior. Replacement of RS with LI and MI evidently increased the elastic properties more than the viscous properties of the RS–inulin blends.

CeO2-CrOx-Nb2O5 mixed oxides were synthesized by three different methods (coprecipitation, deposition-precipitation and mechanical mixing) and subjected for 1,2-dichloroethane (DCE) deep oxidation tests. Detailed characterizations such as XRD, UV-Raman, N2 adsorption/desorption, SEM, XPS, NH3-TPD and H2-TPR were performed. Results show that the synergistic effect between redox and acid properties are critical for promoting the catalytic oxidation of DCE. The CeCrNb-cp prepared by coprecipitation method presents larger specific surface area and mesopore volume as well as smaller particle sizes. Moreover, the highly dispersed state of (Ce,Cr)xO2 in the Nb2O5 matrix can enhance the strong interaction between Nb2O5 and (Ce,Cr)xO2, facilitate the synergy between surface acid sites and oxidation sites, thus improving the destructive efficiency of DCE. The CeCrNb-cp catalyst exhibits excellent catalytic activity for DCE destruction, high selectivity for less toxic products (HCl and CO2), scarce formation of chlorinated byproduct (C2H3Cl) and relatively good durability, all of which indicates it would be promising for potential industrial application.

More wind and solar power will be integrated into future power systems in China. Assessing the complementarity of wind and solar resources helps to mitigate the fluctuation of renewable power output effectively. This study comprehensively assesses the complementarity of wind and solar resources over China based on MERRA-2 reanalysis dataset. The results show that the complementarity between two resources and that between different regions for a single resource are significantly affected by the time scales. The complementarity between wind and PV power plants is superior to that between wind or solar power plants in different regions. Furthermore, the complementarity between wind and PV power can be further improved by dispersing the locations of wind farms, especially when the PV power is significantly positively correlated with wind power at the same location. However, dispersing the locations of PV plants may not work since the diurnal and seasonal solar radiation are highly similar in different regions. Extreme value analysis is employed to assess the benefits obtained from the wind-solar complementarity. The duration of no power output and the hourly negative fluctuation in power output are significantly reduced due to the complementarity.

The Λ-S electronic states with respect to the lowest four dissociation limits of BeSb are investigated theoretically on the icMRCI + Q level employing basis set of quintuple-ζ quality. The geometrical parameters, potential energy curves, vibrational energy levels, spectroscopic constants for the twelve Λ ‐ S states are obtained, analyzed and compared with those of the Beryllium-VA group diatomic family species where data are available. The permanent dipole moments, transition dipole moments, Einstein emission coefficients, radiative lifetimes and Franck-Condon factors for interested Λ ‐ S states are also derived. Further assessments of the spin-orbit coupling effect are performed for states associated with the first two dissociation asymptotes of BeSb. Four Λ ‐ S states split into seven Ω states, and some of the PECs are distorted significantly through the spin-orbit coupling effect, which is similar to its isovalent diatomics BeAs. In consideration of potential risks of manipulating beryllium-containing species directly, the information associated with molecular structures, spectroscopic parameters as well as transition properties that provide in this paper is anticipated to serve as guidelines for further researches of BeSb.

Peer-to-peer (P2P) is a practice of providing loans from lenders directly to borrowers through an online platform. Being rapidly developed, P2P platforms face many hidden risks in the meantime. Besides default risk, operational risk, there exists prepayment risk of borrowers which not only shrinks the investment income of lenders but also disrupts the normal operation of the platform. In this paper, we use Cox proportional hazard model to investigate the influential factors of P2P network loan prepayment risk to provide advice to P2P platforms and investors to avoid prepayment risk.

The assessment of wind resource is the basis of wind power utilization. An accurate and comprehensive characterization of wind resource is of vital importance to site planning, wind turbine selecti ...