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In an attempt to improve implant-bone integration and accelerate bone fracture healing from resisting osteoclastic resorption point of view, we have employed a novel procedure to develop a mesoporous silica nanoparticles/hydroxyapatite (MSNs/HA) composite coating onto stainless Kirschner wire substrate. Characterizations of the surface microstructures indicated enlarged specific surface area compared to HA-coated wires as control, thus the MSNs/HA composite coated implants are endowed with abilities to locally deliver biomedical substances and enhance fracture healing. Herein, zoledronic acid (ZOL) as a model drug, different doses of which were immobilized in the mesoporous coating toward decreasing osteoclastic resorption activity. The loading capacities of ZOL increased almost eight-folds to that of pure HA coating, and the introduction of MSNs obviously retarded ZOL release to achieve a more sustained release profile. After certain periods of osteoclast like cells co-culturing with ZOL contained wires, tartrat-resistant acid phosphatases (TRAP) staining of polynucleated cells and a pit formation assay were performed to investigate the ZOL dose-dependent anti-resorption activity. The promoted local effect on osteoclasts will be of clinical benefit to support implant integration and bone repair.

Resistance to radiotherapy is frequently encountered in clinic, leading to poor prognosis of cancer patients. Long noncoding RNAs (lncRNAs) play important roles in the development of radioresistance due to their functions in regulating the expression of target genes at both transcriptional and posttranscriptional levels. Exploring key lncRNAs and elucidating the mechanisms contributing to radioresistance are crucial for the development of effective strategies to reverse radioresistance, which however remains challenging. Here, actin filament‐associated protein 1 antisense RNA1 (lncAFAP1‐AS1) is identified as a key factor in inducing radioresistance of triple‐negative breast cancer (TNBC) via activating the Wnt/β‐catenin signaling pathway. Considering the generation of a high concentration of reduction agent glutathione (GSH) under radiation, a reduction‐responsive nanoparticle (NP) platform is engineered for effective lncAFAP1‐AS1 siRNA (siAFAP1‐AS1) delivery. Systemic delivery of siAFAP1‐AS1 with the reduction‐responsive NPs can synergistically reverse radioresistance by silencing lncAFAP1‐AS1 expression and scavenging intracellular GSH, leading to a dramatically enhanced radiotherapy effect in both xenograft and metastatic TNBC tumor models. The findings indicate that lncAFAP1‐AS1 can be used to predict the outcome of TNBC radiotherapy and combination of systemic siAFAP1‐AS1 delivery with radiotherapy can be applied for the treatment of recurrent TNBC patients. [ABSTRACT FROM AUTHOR]

Summary: Latent heat storage system using phase change materials (PCMs) has been recognized as one of the most useful technologies for energy conservation. In this study, a novel type of fatty acid eutectic of methyl palmitate (MP) and lauric acid (LA)/polyacrylonitrile (PAN) composite phase change fiber is prepared by single electrospinning method. Additionally, copper nanoparticles (CNPs) with different mass ratio are combined for improving the thermal conductivity of the PCM. The structure and morphology of the fabricated composite PCMs are observed by scanning electron microscopy (SEM), and the thermal properties and performance are also characterized. SEM results show that the liquid fatty acid has been fully stabled by the three‐dimensional structure of the fibers. Good compatibility among the components of the composites is also demonstrated. Besides, the addition of nanoparticles leads to an improved thermal conductivity by over 115.2% and a phase transition temperature 21.24 °C as well as a high latent heat of 85.07 J/g. Moreover, excellent thermal reliability of the phase change fiber is confirmed by multiple thermal cycles. Hence, the composite PCM prepared in this study shows a promising potential for thermal energy system such as building insulating and thermal mass regulating textiles. [ABSTRACT FROM AUTHOR]

The negative impacts of aggressive environment on the durability of concrete materials have raised great concerns in recent years. Although the nano modification has been considered as a promising approach to enhance the durability of concrete materials with exposure to synergistic attacks from complicated aggressive environment, the investigation of the impacts of various chemicals on low dosage nano modified concrete, especially along with freeze/thaw and wet/dry cycles, is still very limited. In this study, the impacts of sodium chloride (NaCl) and potassium acetate (KAc) on laboratory fabricated concrete samples, which were modified with low dosage of nano SiO 2 and nano TiO 2 particles, were investigated. The mass loss, flexural strength, compressive strength, and relative dynamic modulus of elasticity were tested to evaluate the deterioration of low dosage nano modified concrete samples after exposure to F/T along with W/D cycles in KAc and NaCl solutions. The microstructure analyses demonstrate that both NaCl and KAc have negative impacts on the durability of concrete samples after F/T and W/D cycles. However, the addition of low dosage nano particles shows a distinctive enhancement of environment resistance of concrete samples. Through the microstructure analysis, three potential reasons were presented to help elucidate the deterioration mechanisms of concrete with exposure to aggressive environment. Moreover, based on the microstructure analysis, the different modification mechanisms corresponding to various nano materials were presented. This study not only shows the possibility of low dosage nano modification on the durability enhancement of concrete, but also provides potential modification mechanisms which help to design and fabricate durable concrete materials with exposure to complicated aggressive environment. [ABSTRACT FROM AUTHOR]

Nanomodified Portland cement pastewith a water/cement ratio of0.4 was prepared with the addition of TiO2nanoparticlesat 0.1, 0.5, 1.0, and 1.5% by mass of cement. The flexural strengthsof the prepared cement-based composites were tested, and the fracturesurfaces were observed by scanning electron microscopy (SEM). Theflexural strength of the nanomodified TiO2Portland cementpaste reached the highest value with a dosage of 1.0 mass %. The SEMobservation shows that admixing of the TiO2nanoparticleslargely decreased the quantity of internal microcracks in the cementpaste. A new type of needle-shaped hydration product was observed,and its potential growth mechanism was proposed. Atomic force microscopywas introduced to observe the microstructure of nanomodified Portlandcement paste, and the results show that the nanoroughness of the hardenedcement pastes with admixed TiO2nanoparticles was muchlower than that without the TiO2nanoparticle addition.Coupled with X-ray diffraction data, the morphological informationobtained at the micrometer and nanometer scales shed light on therole of TiO2nanoparticles in the cement-based composite. [ABSTRACT FROM AUTHOR]

The phenomenon of rutting is one of the most serious problems on asphalt pavements. Decreasing the surface temperature of the asphalt pavement is an effective method to solve the rutting problem on asphalt pavements. In this study, a nano-sized-particles-filled polymer composite was developed as an overlay to reflect solar energy and decrease the surface temperature of asphalt pavements. The overlay was composed of acrylic or epoxy resin filled with nano TiO2or nano TiNO2. The solar reflection of the nanoparticle-filled polymers was tested, and the results showed that solar reflection effectiveness of the TiO2/acrylic composite reached the highest value. The results of outdoor temperature tests indicate that the solar-reflective overlay could decrease the surface temperature of asphalt pavements by about 10°C when the pavement temperature is about 60°C. [ABSTRACT FROM AUTHOR]

The great demand for gas sensors in practical applications has stimulated tremendous attention in this area due to its important significance in real life. A facile synthesis of WO 3 nanoplates and their subsequent Sn doping strategy by using a hydrothermal method was investigated to enhance gas sensing performance for NO 2 gas, one of the gases toxic to human beings and the environment. Various techniques were used to characterize all the products. The morphology characterizations demonstrated that all the samples exhibited a similar nanoplate structure with or without Sn doping. The gas sensing properties of the sensors based on different doping concentrations (0, 1, 2 and 5 wt%) have been systematically investigated. The sensor based on the 2 wt% Sn-doped WO 3 nanoplates showed the maximum response to NO 2 (55–100 ppb NO 2 ). Furthermore, the introduction of Sn ions into the sensing materials of WO 3 resulted in shorter response and recovery times. This finding could be attributed to the increased number of oxygen vacancies on the surface of the sensing material and the resistance of the gas sensors. The results provide a new doping strategy to fabricate high performance NO 2 gas sensors. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Dispersed WO 3 nanoparticles with high crystallinity, well dispersity and porous nanostructure were successfully synthesized through adjusting hexamethylenetetramine (HMT) amount and subsequent annealing treatment. • The sensor based on dispersed WO 3 nanoparticles sintered at 500 °C possesses the highest response (132.0) towards 100 ppm toluene at the operation temperature of 225 °C. • The sensor also exhibits not only a good selectivity for toluene among various VOC gases but also ultrafast response/recovery time (2 s/6 s) to 100 ppm toluene at the optimal working temperature. • The obtained superior gas sensing properties can be attributed to the high resistance caused by crystallinity and grain boundary, and porous structure of the sensing materials. Abstract The preparation of size-controlled materials has shown remarkable potential with regard to their reinforced sensing performance. Herein, we report a facile solvothermal synthesis of dispersed WO 3 nanoparticles with porous nanostructure caused by particle assembly. Various characterizations of the as-obtained samples were analyzed. Furthermore, the gas sensing properties of WO 3 samples on volatile organic compounds were investigated. The results reveal that the gas sensors based on synthesized WO 3 samples with suitable hexamethylenetetramine (HMT) amount and sintering treatment exhibit the highest response (132.0) towards 100 ppm toluene at the optimal working temperature of 225 °C with fast response/recovery time (2 s/6 s), which is attributed to the porous structure of the sensing film and the high resistance caused by well crystallization and grain boundary among the nanoparticles. [ABSTRACT FROM AUTHOR]