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Numerical modeling of earthquake dynamics and derived insight for seismic hazard relies on credible, reproducible model results. The sequences of earthquakes and aseismic slip (SEAS) initiative has set out to facilitate community code comparisons, and verify and advance the next generation of physics-based earthquake models that reproduce all phases of the seismic cycle. With the goal of advancing SEAS models to robustly incorporate physical and geometrical complexities, here we present code comparison results from two new benchmark problems: BP1-FD considers full elastodynamic effects, and BP3-QD considers dipping fault geometries. Seven and eight modeling groups participated in BP1-FD and BP3-QD, respectively, allowing us to explore these physical ingredients across multiple codes and better understand associated numerical considerations. With new comparison metrics, we find that numerical resolution and computational domain size are critical parameters to obtain matching results. Codes for BP1-FD implement different criteria for switching between quasi-static and dynamic solvers, which require tuning to obtain matching results. In BP3-QD, proper remote boundary conditions consistent with specified rigid body translation are required to obtain matching surface displacements. With these numerical and mathematical issues resolved, we obtain excellent quantitative agreements among codes in earthquake interevent times, event moments, and coseismic slip, with reasonable agreements made in peak slip rates and rupture arrival time. We find that including full inertial effects generates events with larger slip rates and rupture speeds compared to the quasi-dynamic counterpart. For BP3-QD, both dip angle and sense of motion (thrust versus normal faulting) alter ground motion on the hanging and foot walls, and influence event patterns, with some sequences exhibiting similar-size characteristic earthquakes, and others exhibiting different-size events. These findings underscore the importance of considering full elastodynamics and nonvertical dip angles in SEAS models, as both influence short- and long-term earthquake behavior and are relevant to seismic hazard.

For the implementation of power market in China, medium- and long-term security checks are essential for bilateral transactions, of which the electricity quantity that constitutes the generation feasible region (GFR) is the target. However, uncertainties from load forecasting errors and transmission contingencies are threats to medium- and long-term electricity trading in terms of their influences on the GFR. In this paper, we present a graphic distortion pattern in a typical three- generator system using the Monte Carlo method and projection theory based on security constrained economic dispatch. The underlying potential risk to GFR from uncertainties is clearly visualized, and their impact characteristics are discussed. A case study on detailed GFR distortion was included to demonstrate the effectiveness of this visualization model. The result implies that a small uncertainty could distort the GFR to a remarkable extent and that different line-contingency precipitates disparate the GFR distortion patterns, thereby eliciting great emphasis on load forecasting and line reliability in electricity transactions.

It is widely recognized that fluid injection can trigger fault slip. However, the processes by which the fluid-rock interactions facilitate or inhibit slip are poorly understood and some are neglec...

A surface functionalization system targeted for iron-based materials is developed by combining two biodegradable components, iron oxide nanostructured arrays and polycaprolactone (PCL) coatings. Iron oxide nanoporous and nanotubular arrays are superior surface functionalization matrices, while their stability and cytocompatibility can be further improved by PCL coatings, the morphology of which can modify the drug release behavior. The biodegradation behavior of this system was investigated firstly by electrochemical tests, and further biodegradation information (including the surface morphology and chemical composition) was collected from samples used in a long-term in vitro cytocompatibility test over 21 days of incubation with human adipose-derived stem cells (ADSCs). Moreover, the drug release behavior of these arrays coated with various PCL coatings was studied using tetracycline as a model drug. Experimental results demonstrate that PCL coatings can endow iron oxide nanostructured arrays a proper biodegradation behavior with bioactive degradation products on the surface, also leading to high cytocompatibility characterized by the production of collagen type I and cell distribution on the PCL-coated samples. Furthermore, with the barrier effect of PCL, the whole functionalization system shows sustainable drug release behavior.

Magnesium, as a biodegradable metal, is a promising candidate for biomedical applications. To modify the degradation behavior of magnesium and improve its osteocompatibility, chemical conversion and spin coating methods were combined to develop a diammonium hydrogen phosphate-pretreated/poly(ether imide) (DAHP/PEI) co-coating system. The diammonium hydrogen phosphate pretreatment was employed to enhance the attachment between PEI coatings and the magnesium substrate; meanwhile, it could serve as another bioactive and anticorrosion layer when PEI coatings break down. Surface characterization, electrochemical tests, and short-term immersion tests in DMEM were performed to evaluate DAHP/PEI coatings. Electrochemical measurements showed that DAHP/PEI coatings significantly improved the corrosion resistance of pure magnesium. No obvious changes of the chemical compositions of DAHP/PEI coatings occurred after 72 h of immersion in DMEM. An in vitro cytocompatibility study confirmed that viability and LDH activity of human osteoblast-like cells on DAHP/PEI coatings showed higher values than those on the DAHP-pretreated layer and pure magnesium. The DAHP-pretreated layer could still enhance the ALP activity of MG-63 cells after the degradation of PEI in DAHP/PEI coatings. Besides that, the in vitro cellular response to the treated magnesium was investigated to gain knowledge on the differentiation and proliferation of human adipose-derived stem cells (hADSCs). Cell distribution and morphology were observed by fluorescence and SEM images, which demonstrated that DAHP/PEI coatings facilitated cell differentiation and proliferation. The high level of C-terminals of collagen type I production of hADSCs on DAHP/PEI coatings indicated the potential of the coating for promoting osteogenic differentiation. Positive results from long-term cytocompatibility and proliferation tests indicate that DAHP/PEI coatings can offer an excellent surface for hADSCs.

Inflammation widely occurs in various tissues and organs in the human body. Rapid and accurate diagnosis of inflammation is essential to avoid severe complications. This study aims to obtain a non-destructive, fast, and comprehensive tool for the detection of pathogenic sites of inflammation in vivo. A fluorescence and photoacoustic dual-mode imaging probe, Cy-ASP, was first developed to detect inflammatory biomarker LTA4H with good sensitivity and selectivity in living small animal. Furthermore, the relationship between LTA4H and NF-κB in an LPS-induced cell was investigated. This work provides a new idea for the clinical diagnosis of pneumonia and hepatitis and revealing the upstream regulatory mechanism of LTA4H in the pneumonia model.

As an essential amino acid, cysteine is involved in various biosynthetic and metabolic processes, such as protein synthesis, hormone synthesis, and redox homeostatic maintenance. Inordinate cysteine levels are often associated with serious diseases. Thus, designing and synthesizing a novel fluorescent probe for determining the concentration of cellular cysteine, which could indirectly monitor the prevalence of these diseases, is essential. We developed a florescence probe P−Cy with good sensitivity for cysteine detection in vivo. P−Cy only exhibited good response toward cysteine but did not show response toward other biothiols, such as homocysteine (Hcy) and glutathione (GSH). In this study, we used P−Cy by successfully imaging cellular endogenous and exogenous cysteine levels. Furthermore, P−Cy was also performed in mice to detect cysteine level, indicating that P−Cy is a powerful tool for cysteine detection in situ.

Biodegradable polymer coatings on magnesium alloys are attractive, as they can provide corrosion resistance as well as additional functions for biomedical applications, e.g., drug delivery. A gelatin nanospheres/chitosan (GNs/CTS) composite coating on WE43 substrate was fabricated by electrophoretic deposition with simvastatin (SIM) loaded into the GNs. Apart from a sustained drug release over 28 days, an anticorrosion behavior of the coated WE43 substrates was confirmed by electrochemical tests. Both the degradation and corrosion rates of the coated substrate were significantly minimized in contrast to bare WE43. The cytocompatibility of the coated samples was analyzed both quantitatively and qualitatively. Additionally, the osteogenic differentiation of MC3T3-E1 cells on SIM-containing coatings was assessed by measuring the expression of osteogenic genes and related proteins, alkaline phosphatase (ALP) activity, and extracellular matrix mineralization, showing that the SIM-loaded composite coating could upregulate the expression of osteogenic genes and related proteins, promote ALP activity, and enhance extracellular matrix mineralization. In summary, the SIM-loaded GNs/CTS composite coatings were able to enhance the corrosion resistance of the WE43 substrate and promote osteogenic activity, thus demonstrating a promising coating system for modifying the surface of magnesium alloys targeted for orthopedic applications.

Chitosan as a natural biopolymer was immobilized and chelating-deposited with and without bioactive glass (BG) onto Mg substrates by means of a chemical conversion process at 75 °C to provide anti-corrosion properties, good adhesion and biocompatibility. The aim of the present work was to integrate the surface of biodegradable Mg as a part of the corrosion resistant coating via metal-chitosan complexation process. The surface morphology and composition of the coatings were characterized by Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). The results provided evidence of the formation of a chitosan coating as well as its chelating reaction and immobilization on magnesium by a chemical conversion process. The non-alkalization of the chitosan solution was ascribed to the protective layer of Mg (II)-chitosan complex, which inhibits the further migration of Mg ions. The in vitro bioactivity of both chitosan (CHI)-coated and chitosan/BG (CHI/BG)-coated surfaces in simulated body fluid (SBF) proved the complete retention of chitosan and BG on the magnesium substrates. The XRD analysis of the (CHI/BG) coating after 2 weeks immersion in SBF showed mainly the formation of magnesium hydrogen phosphate hexahydrate and undetected amorphous (Ca, Mg) phosphate. The present study represents a novel attempt to modify the surface of Mg by a simple, one-step chemical conversion treatment in chitosan to form a Mg (II)-chitosan complex layer. Mechanisms for the Mg-chitosan complexation process and for the coating bioactivity behavior in SBF were discussed.

We developed a photoacoustic and fluorescent dual-mode imaging probe, CCYS, for the detection of cysteine with high selectivity and sensitivity in a living system for the first time. By using CCYS, we found that the limited synthesis of glutathione in pulmonary fibrosis was not caused by cysteine deficiency.

Golgi oxidative stress is significantly associated with the occurrence and progression of hypertension. Notably, the concentration of hydrogen peroxide (H2O2) is directly proportional to the degree of Golgi oxidative stress. Therefore, based on a novel Golgi-targeting phenylsulfonamide group, we developed a two-photon (TP) fluorescent probe, Np-Golgi, for in situ H2O2 ratiometric imaging in living systems. The phenylsulfonamide moiety effectively assists Np-Golgi in the precise location of Golgi apparatus. In addition, the raw material of phenylsulfonamide is easily available, and chemical modification is easily implemented. By application of Np-Golgi, we explored the generation of H2O2 during Golgi oxidative stress, and also successfully revealed increases on the levels of Golgi H2O2 in the kidneys of mice with hypertension. This work provides an ideal tool to monitor Golgi oxidative stress for the first time and novel drug targets for the future treatment of hypertension.

Golgi pH homeostasis affects many different biological processes, including glycosylation. Recent studies have demonstrated that transmembrane protein 165 (TMEM165) deficiency leads to Golgi glycosylation abnormalities by disturbing Golgi pH homeostasis. However, due to the lack of specific tools to measure Golgi pH in situ, evidence for TMEM165 involvement in H+ transport in the Golgi apparatus is still absent. Herein, the photoacoustic and fluorescent dual-mode probe CPH was developed for ratiometric detection of Golgi pH. CPH was proved to accumulate in the Golgi apparatus and reversibly image Golgi pH in real-time with high sensitivity in cells. Furthermore, we found that the absence of TMEM165 influenced H+ equilibrium and caused Golgi apparatus acidification. Our work provides strong evidence that TMEM165 regulates Golgi pH homeostasis. Moreover, we believe that CPH has the potential to be a practical tool to monitor Golgi pH in various biological processes.

Fault-zone fluids control effective normal stress and fault strength. While most earthquake models assume a fixed pore fluid pressure distribution, geologists have documented fault valving behavior, that is, cyclic changes in pressure and unsteady fluid migration along faults. Here we quantify fault valving through 2-D antiplane shear simulations of earthquake sequences on a strike-slip fault with rate-and-state friction, upward Darcy flow along a permeable fault zone, and permeability evolution. Fluid overpressure develops during the interseismic period, when healing/sealing reduces fault permeability, and is released after earthquakes enhance permeability. Coupling between fluid flow, permeability and pressure evolution, and slip produces fluid-driven aseismic slip near the base of the seismogenic zone and earthquake swarms within the seismogenic zone, as ascending fluids pressurize and weaken the fault. This model might explain observations of late interseismic fault unlocking, slow slip and creep transients, swarm seismicity, and rapid pressure/stress transmission in induced seismicity sequences., Coupling between fault zone fluid flow, permeability evolution, and elastic stress transfer produces fault valving and fluid-driven aseismic slip and pore pressure pulses. This model might explain late interseismic fault unlocking, slow slip, and rapid pressure transmission in induced seismicity.

Severe atmospheric haze caused by industrial pollution has severely affected human health and led to the increasing incidence of cardiopulmonary diseases, including pneumonia. Conventional methods for diagnosis of pneumonia are complicated and tedious, and current clinical imaging techniques might cause organ injuries to some extent. Therefore, an accurate, fast, and intact imaging method must be developed to diagnose pneumonia in the early stages. In this study, we propose a new two-photon fluorescence probe, named as ASPC, for detection of the activity of the inflammatory biomarker LTA4H through specific recognition and cleavage of amides containing the unnatural amino acid l-AspBzl. The activity of LTA4H in the lung tissues of mice was rapidly and accurately monitored for the first time and could be an indicator for diagnosis of pneumonia. The severity of pneumonia in mice caused by haze particulate was determined through imaging the activity of LTA4H as biomarker and confirmed using a commercial ELISA...

A local drug delivery system consisting of superhydrophobic titanium oxide nanotube (S-TNTs) arrays and ultrasonic-controlled release trigger was developed in this work. Hydrophilic TNTs arrays are converted into superhydrophobic after being treated by 1H,1H,2H,2H- perfluorooctyl-triethoxysilane (POTS). S-TNTs arrays serving as a drug-carrying vehicle require no extra sealing treatment due to the excellent isolation effect from the trapped air layer on the surface. Different amounts of drugs could be loaded into S-TNTs arrays by control of the structure of arrays (including length and diameter of tubes) and the original amount of drug in the drug-loading solution. The relation between surface morphology of TNTs arrays and superhydrophobicity (isolation effect) was thoroughly investigated. To achieve a stimulus-responsive drug delivery system, ultrasonication was employed as an efficient drug release trigger. Trapped air layer could be selectively removed by ultrasonication, and therefore the loaded drug could be released in a multiple and controlled manner. Any drugs that can dissolve in nonpolar solutions are expected to be suitable for this local drug delivery system.

NiTi98-xSixC2 (x = 0, 4, 8 wt%) coatings were prepared on Ti-6Al-4V substrate by laser cladding to improve the surface mechanical properties of NiTi coatings. The effects of Si content addition on the microstructure, phase composition, microhardness, and tribological properties of the coatings were systematically analyzed. The results show that NiTi98-xSixC2 (x = 0, 4, 8) coatings are mainly composed of NiTi, NiTi2, TiC, and Ti5Si3 phases. The rod-like phase of Ti5Si3 was found in NiTi90Si8C2 coating, while the rod-like phases were found broken. The fragmentation of the rod-like phase is related to the growth of the NiTi phase around it. At the same time, TEM results show that the NiTi (B2) phase and Ti2Si second phase are exited in the NiTi90Si8C2 coating. Ti2Si, which has not been decomposed into Ti5Si3, remains during the laser cladding process. In addition, the eutectic structure in NiTi90Si8C2 coating was observed in some regions. The average microhardness of the NiTi98-xSixC2 (x = 0, 4, 8) coating were at 534.08 HV0.5, 598.06 HV0.5, and 974.08 HV0.5, respectively. The wear resistance of NiTi98-xSixC2 (x = 0, 4, 8) coatings increased with the increased Si content. The NiTi90Si8C2 coating exhibits the highest microhardness (974.08 HV0.5) and wear resistance (friction coefficients, wear trace, widths loss weight, and wear rate are 0.320, ~1.25 mm, 12.2 mg, and 5.78 × 10−6 g/Nm, respectively). In NiTi90Si8C2 coating, Ti5Si3 phase plays a significant role in the second phase strengthening to improve its tribological properties. The above analysis confirms that NiTi90Si8C2 coating has optimal tribological properties.

In recent years, graphene (Gr) has attracted much attention owing to its excellent reinforcement effects. However, the application of Gr in laser cladded coatings remains a challenge due to the agglomeration of Gr and poor wettability between Gr and the molten metals. To overcome these problems, in this study, Ni modified Gr (Ni@Gr) powders were synthesized by electroless plating method, and Ni@Gr powders reinforced Ni60 (Ni60-Ni@Gr) composite coatings were prepared on the surface of AISI 1045 steel by laser cladding technique. The microstructure, existential state of Gr nanosheets, micro-hardness, wear resistance and corrosion resistance of Ni60-Ni@Gr coatings, Ni60-Gr coatings and Ni60 coatings were studied by SEM, TEM, XRD, Raman, micro-hardness tester, wear tester and electrochemical tester. The results showed that the wettability between the metal matrix and Gr was improved after modification, which promotes the dispersion of Gr nanosheets. The average micro-hardness value of Ni60-Ni@Gr coating was 920.79 HV0.2, which was higher than that of Ni60-Gr coatings (843.80 HV0.2) and Ni60 coatings (777.13 HV0.2). Compared with Ni60-Gr coatings and Ni60 coatings, the Ni60-Ni@Gr coatings have the lowest friction coefficient and weight loss, indicating the best wear resistance of Ni60-Ni@Gr coatings. The potentiodynamic polarization test and EIS test indicated that the corrosion resistance of Ni60 coatings was significantly improved after adding Gr. More notably, compared with the Gr without modification, the addition of modified Gr contributes to the further improvement of the corrosion resistance of Ni60 coating, which was related to the excellent barrier property of uniformly dispersed Ni@Gr powders in coatings.

The new parameter e we proposed in this study is to be more conducive to the hardness design of high-entropy alloy coatings. Here, the parameter e is defined as the ratio of the atomic size mismatch to the atomic stacking mismatch. This parameter can be used as the criterion for measuring the magnitude of lattice distortion caused by the atomic size effect, which reveals the influence of the atomic size effect on the hardness of the alloy. We collected nearly 100 groups of on high-entropy alloy coatings in order to verify the feasibility of parameter e, and to analyze the relevant data from available literatures by using the parameter e. We found that the hardness value of the high-entropy alloy coatings showed monotonicity with the e increased. When e 6.4, hardness value of the coating escalates with the increase of parameter e. Based on this finding, it is suggested that the parameter e can then be used to design a high-entropy alloy coatings with the desired hardness.

Molecular dynamics (MD) simulation was successfully used to explore the mechanism of carbon atom diffusion in supersonic fine particle bombardment (SFPB) pretreated low carbon alloy steel during vacuum carburization. Results of experiment and simulation demonstrated that the plastic deformation was occurred and high surface energy achieved on the surface of low carbon alloy steel during the process of SFPB. The defects were formed inside the crystal including vacancies, 1/2 , and types of dislocations, and the number of defects gradually increased with the increase of bombardment time and speed. Compared with defect-free materials, the large number of defects increase the diffusion coefficient by several orders of magnitudes. The internal defects of the material, including vacancies, dislocations and grain boundaries induce the rise of carbon atom diffusion coefficient, accordingly. While the effect of dislocation types was not obvious to diffusion coefficient. The carburizing temperature has a significant effect on the carbon atom diffusion rate of SFPB pretreated samples, when comparing with that of non-pretreated ones.

The surface nanocrystallization layer induced by supersonic fine particle bombardment (SFPB) was obtained on a structural steel. SFPB was applied as pretreatment on the steel prior to the vacuum carburization, for enhancing the tribological properties under various sliding conditions. Varying duration of pretreatment was performed to investigate the influence on microstructure, surface hardness, and tribological behavior of the carburized substrates. Results suggested that 240s of SFPB pretreatment induced finer grain boundaries and higher hardness. A decrease in weight loss and friction coefficient under unlubricated and lubricated sliding conditions indicated enhanced tribological properties of the 240s SFPB nanocrystallized steel after vacuum carburization. Notably, the lowest friction coefficient was achieved under sea water sliding condition, whereas the highest weight loss was obtained. Rolling contact fatigue behavior of the carburized steel with SFPB 240s pretreatment was discussed and Weibull life distribution was proposed in the study.

Zinc (Zn)-containing materials have osteogenic and antibacterial activities while bioactive glass nanoparticles (BGN) show bone-bonding ability, as well as osteoconductive and osteoinductive properties. Zn-containing BGN are therefore considered to be promising materials for various biomedical applications, particularly in bone regeneration. In this study, we report a convenient method to prepare Zn-containing BGN by coating ZnO quantum dots (QDs) on BGN via electrostatic interactions. The synthesized ZnO–BGN nanocomposite particles are spherical and highly dispersed, and exhibit a unique fluorescence behavior under UV excitation, emitting three wavelengths in the violet, blue and green range. ZnO–BGN showed apatite-forming ability upon immersion in simulated body fluid, but their apatite formation was delayed compared to BGN. Interestingly, ZnO–BGN showed a rapid release of Zn ions at pH 4 but a far slower release at pH 7.4. ZnO–BGN also exhibited antibacterial effects on both Gram-positive and Gram-negative bacteria at the concentrations of 1, 0.1, and 0.01 mg mL−1. Higher concentrations could lead to stronger antibacterial effects. The LDH and live/dead assays indicated that ZnO–BGN had no significant cytotoxicity towards human mesenchymal stem cells (hMSC) at concentration of 0.1 and 0.01 mg mL−1, but ZnO–BGN inhibited the relative proliferation of hMSC compared to BGN and the control according to the MTT assay. Notably ZnO–BGN improved the osteogenic differentiation of hMSC as indicated by the determination of the alkaline phosphatase activity. In conclusion, coating quantum dots on BGN is a promising strategy to produce Zn-containing BGN. The synthesized ZnO–BGN are potential materials for bone regeneration, considering their apatite-forming ability, unique ion-release behavior, effective antibacterial activity, non-cytotoxicity, and osteogenic potential.

An organic-inorganic nanocomposite coating consisting of fibrous cellulose nanocrystals and 45S5 bioactive glass, intended as a bioactive surface for bone implants, was developed by a one-step electrophoretic deposition. The composition, surface roughness and wettability of the deposited coatings, influenced by the concentration of each component in the suspension, were controllable as a result of the simplicity of the coating technique. Bioactive glass particles were individually wrapped with porous cellulose layers, forming a porous coating with uniform thickness. Bioactivity test in simulated body fluid revealed a rapid hydroxyapatite formation on the deposited nanocomposite coating. Furthermore, electrochemical test was carried out to understand the corrosion behavior of the deposited coatings during incubation in simulated body fluid. According to the results of this study, the obtained cellulose-bioactive glass coatings with tunable properties represent a promising approach for biofunctionalization of metallic orthopedic implants.

The influence of the addition of nano-scaled bioactive glass (nBG) powder into polycaprolactone (PCL) coatings on the biodegradation and bioactivity of pure Mg was investigated in the present work. Scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Fourier transform infrared spectroscopy (FTIR) and electrochemical methods were employed to characterize the morphology, chemical composition and anticorrosion properties of the coatings. The results indicate that nBG addition in PCL increases the degradation of PCL in physiological solution; depending on the amount of nBG in the composite coating, the barrier properties of PCL therefore can be modified. At the same time, the addition of nBG facilitates the formation of hydroxyapatite during 7 days immersion in simulated body fluid (SBF).

Composite 3D scaffolds combining natural polymers and bioceramics are promising candidates for bone tissue engineering (BTE). Zein, as a natural plant protein, offers several advantages, including biocompatibility, adequate strength properties, and low/no immunogenicity; however, it lacks bioactivity. Thus, composite zein: bioactive glass (BG) scaffolds are proposed as promising candidate for BTE applications, with silver-doping of bioactive glass providing an antibacterial effect against possible post-implantation infection. Therefore, the aim of this study was to investigate the in vitro antibacterial properties, biocompatibility, bioactivity and compressive strength of zein scaffolds containing silver-doped bioactive glass. BG nanoparticles, undoped and Ag-doped, were fabricated using the sol-gel method. 3D composite zein:BG scaffolds, containing 20 wt% BG, were prepared and their antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was assessed using the disc diffusion assay. Human osteoblast-like MG-63 cells were used to evaluate the in vitro biocompatibility of the prepared scaffold groups. In addition, the compressive strength of the scaffolds was determined using uniaxial compression strength testing and the scaffold interconnected porosity was measured using helium pycnometer. Disc diffusion assay showed that only zein scaffolds containing Ag-doped sol-gel BG are antibacterially positive against E. coli and S. aureus. Pure zein scaffolds and zein scaffolds containing sol-gel-derived BG showed no negative influence on the growth of MG-63 cells, as evident by the cells' ability to survive, proliferate, and function on these scaffolds. Moreover, incorporating sol-gel-derived BG into zein scaffolds at zein:BG of 80:20 ratio showed bioactive properties with adequate porosity without affecting the scaffolds' compressive strengths, which was similar to that of trabecular bone, suggesting that the new composites have potential for BTE applications in non-loaded bearing areas.

Electrospun hybrid scaffolds are an effective platform to deliver drugs site specifically for the prevention and treatment of diseases in addition to promote tissue regeneration because of the flexibility to load drugs therein. In the present study, electrospun hybrid scaffolds containing antibiotics were developed to support cellular activities and eliminate potential postoperative inflammation and infection. As a model drug, levofloxacin (LFX) was successfully incorporated into pure polyhydroxybutyrate/poly(epsilon-caprolactone) (PHB/PCL) scaffolds and PHB/PCL/sol-gel-derived silica (SGS) scaffolds. The influence of LFX on the morphology, mechanical performance, chemical structure, drug release profile, and antibacterial effect of the scaffolds was thoroughly and comparatively investigated. MG-63 osteoblast-like cell cultivation on both scaffolds certified that LFX inclusion did not impair the biocompatibility. In addition to the favorable cellular proliferation and differentiation, scaffolds containing both LFX and SGS displayed highly increased mineralization content. Therefore, the present multifunctional hybrid scaffolds are promising in tissue engineering applications.

Severe atmospheric haze caused by industrial pollution has severely affected human health and led to the increasing incidence of cardiopulmonary diseases, including pneumonia. Conventional methods for diagnosis of pneumonia are complicated and tedious, and current clinical imaging techniques might cause organ injuries to some extent. Therefore, an accurate, fast, and intact imaging method must be developed to diagnose pneumonia in the early stages. In this study, we propose a new two-photon fluorescence probe, named as ASPC, for detection of the activity of the inflammatory biomarker LTA

An ultrasonication treatment is developed as an external method to control the degradation behavior of pure iron. Immersion tests (weight loss measurements) and electrochemical measurements were conducted in two different pseudo-physiological solutions, simulated body fluid (SBF) and Dulbecco's modified Eagle medium (DMEM) solution. By the comparison study in these two different solutions, more information and the mechanism of the degradation process can be revealed. Degradation morphologies (with and without ultrasonication treatment) were observed by scanning electron microscope (SEM), and degradation products on the surface were characterized by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Moreover, the biocompatibility of iron surfaces after being ultrasonicated was evaluated. Ultrasonication was found to accelerate the degradation rate in DMEM, while it makes no difference in SBF solution; the origin of this different behavior is investigated and discussed. The parameters of the ultrasonication treatment, intensity and frequency, show an influence on the degradation rate. No adverse effects on the proliferation and adhesion of human osteoblast-like cells (MG-63) are observed on surfaces after ultrasonication treatment, as compared to bare iron. Based on these results, ultrasonication treatment is considered to have high potential to control the biodegradation behavior of iron-based materials in an external and flexible manner.

Bioactive glass nanoparticles containing copper (Cu-BGNs) were introduced into polycaprolactone (PCL) coating systems to improve the bioactivity, antibacterial properties, and corrosion resistance of vulnerable magnesium matrices under physiological conditions. The influence of different amounts of Cu-BGNs in PCL coatings was thoroughly investigated in determining the wettability, electrochemical properties, and antibacterial effects against Staphylococcus carnosus and Escherichia coli, as well as their cyto-compatibility. Cu-BGNs were observed randomly scattered in PCL coatings. Increasing the concentration of Cu-BGNs resulted in a slight decrease of the water contact angle, and a reduction in anticorrosion properties of the Cu-BGN composite coatings. Yet higher Cu-BGN content in coatings led to more calcium phosphate formation on the surface after 7 days of immersion in Dulbecco's modified Eagle's medium, which was confirmed by Fourier-transform infrared spectroscopy and x-ray photoelectron spectroscopy. The growth of S. carnosus and E. coli was inhibited by Cu2+ ions released from the Cu-BGN coatings. In addition, both direct and indirect cyto-compatibility experiments showed that the viability and proliferation of MG-63 cells on Cu-BGN coatings were highly increased compared to pure magnesium; however, an additional increase of Cu-BGN concentration showed a slight decrease of cell proliferation and cell activity. In summary, Cu-BGN/PCL composite coatings impart magnesium-based biomaterials with antibacterial and anticorrosive properties for clinical applications.