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A Cd(II)-based metal–organic framework as fluorescent chemical sensor, formulated as {[Cd3(bmipia)2]·10DMF·5H2O}n (FCS-2), was synthesized through a hydrothermal process and structurally characteri...

With the rapid growth in electronic device performance, there has been an increasing demand for thermally conductive polymer composites to handle the thermal management issue, thus contributing to the great importance to develop the graphene framework, which is evaluated as the most promising reinforcements for enhancing the thermal conductivity of polymer. Vacuum filtration is a common method to fabricate graphene framework, whereas, it is available to prepare a framework with centimeter-scale thickness by filtrating the graphene-water dispersion, due to the fact of sample cracking caused by the mismatch of surface tension between graphene and water. In this work, a surfactant-assisted strategy was proposed by adjusting the surface tension of the water close to that of graphene first, then performing a conventional filtration process, to fabricate graphene framework. As a result, a thick graphene framework (thickness: 3 cm) was successfully prepared, and after embedding into epoxy, the framework endows the composite (13.6 wt%) with a high in-plane thermal conductivities of 12.4 W/mK, which is equivalent to ≈ 64 times higher than that of neat epoxy. Our method is simple and compatible with the conventional filtration process, suggesting great potential for the mass-production of graphene framework to meet the practical application requirements.

Renewable thermoplastic starch (TPS) was modified by poly (vinyl alcohol) (PVA) with varying degrees of polymerization (DPs) or scCO2-assisted processing to prepare TPSxPVAyz or scCO2TPSxPVAyz fully biodegradable blends. The TPSxPVAyz (or scCO2TPSxPVAyz) films showed the smallest free volume characteristics and oxygen transmission rates (OTRs), as their PVA loadings approached an optimum value. The smallest free volume characteristics and OTRs evaluated for each optimal TPSxPVAyz (or scCO2TPSxPVAyz) films reduced noticeably as their DPs reduced from 2400 to 300. Considerably smaller OTRs and free volume characteristics were acquired for scCO2TPSxPVAyz films than those of corresponding TPSxPVAyz films prepared without the assistance of scCO2. An essential result is that the OTR of the optimal scCO2TPSxPVAyz film with a moisture content of 4wt% was merely 4.6 cm3/m2∙day∙atm. This OTR is as good as that of the polyvinylidene chloride oxygen barrier packaging. Dynamic mechanical relaxations and WAXD characterizations revealed that TPS and PVA are miscible, as PVA loadings were ≤ the optimum values. The enhanced oxygen barrier resistance and reduced free volume characteristics for optimal TPSxPVAyz and scCO2TPSxPVAyz films are partly ascribed to the strengthened molecular interactions between O–H groups of TPS and PVA, as they were processed with the assistance of scCO2, optimum PVA loadings or diminished DPs.

Potassium (K+) ions are essential minerals that are important in maintaining fluid and electrolyte balance in biological systems and regulating bodily functions. However, abnormal K+ concentration level will cause numerous health problems or diseases. Therefore, the effective detection of physiological K+ level is very important in the healthcare field. In this work, we designed, fabricated and characterized solution-gated field effect transistors (FETs) based on high quality CVD graphene for highly sensitive and selective detection of K+ ions. O2 plasma pre-processing for 10 s yielded a limit of detection (LOD) down to 0.058 pM, and a linear dynamic range spanning from sub-0.1 pM to 100 nM. Meanwhile, as the G-quadruplex conformation possesses strong affinity for K+, the FETs exhibit excellent discrimination against other common cations, such as Na+ and Fe3+. As a result, the solution-gated graphene FETs with enhanced sensitivity and selectivity for K+ can be applied to health monitoring and disease prevention.

Background Various types of pulmonary diseases are associated with iron deficiency. However, information on iron status in coronavirus disease 2019 (COVID-19) is scarce. Methods This study included 50 hospitalized patients with confirmed COVID-19. The role of serum iron in predicting severity and mortality of COVID-19 was evaluated. Results The most common symptoms of COVID-19 patients in this study were cough (82%), fever (64%), and chest distress (42%). Of the 50 patients, 45 (90%) patients had abnormally low serum iron levels (, Serum iron deficiency occurs in COVID-19. Critically ill patients with COVID-19 who died during hospitalization had significantly lower serum iron levels compared with those survivors. Decreased serum iron level can predict the transition of mild to critical COVID-19.

Graphene has been demonstrated as an effective reinforcement for metal matrix composites, due to its excellent mechanical properties, robust chemical inertness, thermal stability, and self-lubricating. Nevertheless, the limiting factor for its further use in metal matrix composites, is to realize the homogeneous dispersion of graphene for taking advantage of its exceptional and fascinating properties, because of the poor wettability and density contrast between metal matrix and graphene. Herein, we design a gel-assisted route to synthesize high-quality graphene nanoplatelets modified monodispersed copper particles, followed by hot pressing to fabricate graphene reinforced copper matrix composites bulk. This simple route with high efficiency and low cost, offers a new solution for the mass-production of graphene reinforced copper matrix composites and other graphene-based composites on an industrial scale. Significantly enhanced tensile strength of 253 MPa, and yield strength of 145 MPa, accompanied by the low friction coefficient and improved wear resistance, can be simultaneously achieved in the composites. For the real electrical contact performance test, the service life of electrical contacts made of graphene reinforced copper matrix composites, is 10 times longer as that of the commercial pure copper electrical contacts and almost comparable to CuAg20 contacts, demonstrating its superior ability to solve the electrical contact issues in electrical engineering systems.

The influence on the performances of chemical vapor deposition (CVD) diamond coating/cemented carbide substrate was investigated through comparing the treatments of deionized water, ethanol and hydrogen peroxide after acid reaction. The surface morphology, content and composition of the treated cemented carbide were investigated by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The as-fabricated, in different treatments, diamond coatings' quality and adhesion were detected by Raman spectroscopy and indentation testing, respectively. Moreover, the cutting performance of as-fabricated diamond coatings was studied when the pre-treatments apply to the cutting tools. The results demonstrated that the surface of the cemented carbide, treated by ethanol, precipitated out impurities like Cobalt sulfide and Cobalt sulphate which will lead to poor adhesion, and its scratch test critical load (when delamination occurred) was 27 N. In contrast, the other two ways have the similar better effect: their critical loads were 68 N and 65 N. And the cutting test against Al-SiC alloy indicated that the tool treated with peroxide after a chemical etching had better performance.

Graphene shows great promise as a high-efficiency electrothermal film for flexible transparent defoggers/defrosters. However, it remains a great challenge to achieve a good balance between the production cost and the properties of graphene films. Here, we proposed a cost-effective self-assembly method to fabricate high-performance, large-area graphene oxide/electrochemically exfoliated graphene hybrid films for heater applications. The self-assembled graphene hybrid films with the area of 20 × 20 cm2 could be transferred onto arbitrary substrates with nonplanar surfaces and simply patterned with the hard mask. After reduction by hydrogen iodide vapor followed by 800 °C thermal treatment, the hybrid films with the transmittance of 76.2% exhibit good heating characteristics and defogging performance, which reach a saturation temperature of up to 127.5 °C when 40 V was applied for 60 s.

Nanoparticle-built MgO hollow microspheres were synthesized through a template-free hydrothermal route using citrate as a structural director. Zn was introduced into MgO to improve the surface charge. Pure MgO and Zn-doped MgO samples were characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectrometry (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and a zeta-potential analyzer. The as-prepared microspheres showed outstanding performance for the removal of Congo red (CR, anionic dye) from solutions. The maximum adsorption capacities of pure MgO and Zn-doped MgO samples were 3022.02 and 2953.39 mg g-1, respectively. The Zn-loaded sample only required 45 min to reach equilibrium, which was much shorter than that of pure MgO sample (120 min) and most previously reported adsorbents. The high adsorption capacity and efficiency for CR removal resulted from the samples' unique porous structures and positive surface charges at pH 7. The adsorption process followed Langmuir isotherm and pseudo-second-order model. Regeneration assessment was conducted by a method of calcining for four times, and the observed steady adsorption efficiency indicated a bright prospect for the two samples in wastewater treatment.

Exfoliation of graphene flakes in solution is a high-yield and low-cost synthesis method, but the quality of the obtained graphene flakes is not high, because of the presence of functional groups and structural defects. Therefore, the ability to synthesize high-quality graphene with excellent electrical properties is desirable for electronic applications. Here, we present a facile and rapid annealing approach with nickel for structural repair in isolated graphene flakes on rough insulating substrates, accompanied by lateral stitching of the isolated parts to form a continuous and monolithic film. This process involves the active carbon species being coalesced at the desaturation edge of graphene flakes. Meanwhile, the defects in graphene can be also repaired to improve its crystal quality and electrical properties. Significantly, the carrier mobility of graphene with excellent structural properties is >1000 cm2 V–1 s–1 on average, nearly 10 times higher than that of the process with copper or 100 times hi...

Background: Paracrine factors secreted by endothelial progenitor cells (EPCs) are suggested to be responsible, in part, for the improved microvascular development in bronchopulmonary dysplasia (BPD) models. This study aims to investigate the potential role of exosomes derived from EPCs (EPC-EXOs), a component of paracrine secretion, in angiogenesis by mediating the activity of PMVECs exposed to hyperoxia. Methods: EPCs were isolated from bone marrow of rats. EPC-EXOs were isolated by ExoQuick-TC kits from the conditioned media of EPCs. The PMVECs were divided into three groups, including the normal group, the hyperoxia group (exposed to 85% O 2 ) and the EPC-EXOs treatment group (exposed to 85% O 2 and EPC-EXOs with the concentration of 100 µg/mL). The activities of proliferation, migration and tube formation of PMVECs were detected at the endpoint. The mRNA and protein expression levels of VEGF, VEGFR2 and eNOS in different groups were detected by real-time quantitative PCR and western blot. Results: We found EPC-EXOs exhibited a cup or biconcave morphology, with the size ranging from 30 to 150 nm, and positive for the characteristic exosomal surface marker proteins, CD63 and TSG101. Comparing to the control group, Hyperoxic stress impaired the proliferation, migration, and tubule formation of PMVECs, and decreased the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF), and vascular endothelial growth factor receptor 2 (VEGFR-2) of PMVECs. Comparing to the hyperoxia group, EPC-EXOs treatment enhanced the bioactivity of PMVECs in vitro , and increased the expression of eNOS, VEGF and VEGFR2. Conclusions: Our data demonstrate EPCs secrete exosomes that have independent angiogenic activity in vitro . This may help explain in part the protective effects of EPCs on hyperoxic injury in the developing lung vasculature and may represent a promising therapeutic strategy for BPD.

Copper-based materials are common industrial products which have been broadly applied to the fields of powder metallurgy, electrical contact, and heat exchangers, etc. However, the ease of surface oxidation limits the durability and effectiveness of copper-based components. Here, we have developed a powder metallurgy process to fabricate graphene/copper composites using copper powders which were first deposited with graphene layers by thermal chemical vapor deposition (CVD). The graphene/copper composites embedded with an interconnected graphene network was then able to be obtained by vacuum hot-pressing. After thermal oxidation (up to 220 °C) in humid air for several hours, we found that the degree of surface oxidation of our samples was much less than that of their pure Cu counterpart and our samples produced a much smaller increase of interfacial contact resistance when used as electrical contact materials. As a result, our graphene/copper composites showed a significant enhancement of oxidation resistance ability (≈5.6 times) compared to their pure Cu counterpart, thus offering potential applications as novel electrical contact materials.

Glaucoma is an optic neuropathy characterized by progressive degeneration of retinal ganglion cells (RGCs). Aberrations in several cytoskeletal proteins, such as tau have been implicated in the pathogenesis of neurodegenerative diseases, could be initiating factors in glaucoma progression and occurring prior to axon degeneration. Developmentally regulated brain protein (Drebrin or DBN1) is an evolutionarily conserved actin-binding protein playing a prominent role in neurons and is implicated in neurodegenerative diseases. However, the relationship between circulating DBN1 levels and RGC degeneration in glaucoma patients remains unclear. In our preliminary study, we detected drebrin protein in the plasma of glaucoma patients using proteomic analysis. Subsequently, we recruited a total of 232 patients including primary angle-closure glaucoma (PACG), primary open-angle glaucoma (POAG) and Posner-Schlossman syndrome (PS) and measured its DBN1 plasma levels. We observed elevated DBN1 plasma levels in patients with primary glaucoma but not in patients with PS compared to nonaxonopathic controls. Interestingly, in contrast to tau plasma levels increased in all groups of patients, elevated drebrin plasma levels correlated with retinal nerve fiber layer defect (RNFLD) in glaucoma patients. To further explore the expression of DBN1 in neurodegeneration, we conducted experiment of optic nerve crush (ONC) models, and observed increased expression of DBN1 in the serum as well as in the retina and then decreased after ONC. This result reinforces the potentiality of circulating DBN1 levels are increased in glaucoma patients with neurodegeneration. Taken together, our findings suggest that circulating DBN1 levels correlated with RNFLD and may reflect the severity of RGCs injury in glaucoma patients. Combining measurement of circulating drebrin and tau levels may be a useful indicator for monitoring progression of neurodegenerative diseases.

Owing to the unfavorable wetting and density difference between graphene and copper, it remains challenging to achieve homogeneous dispersion of graphene for utilizing the unique nature of graphene in copper matrix composites. Here, we design an in-situ process to fabricate graphene-like carbon (GLC) reinforcing copper matrix composites: GLC can be directly fabricated on commercial copper particles using modified PECVD method followed by vacuum hot pressing, which is high-efficiency and can be massively produced for graphene reinforced metal matrix composites in industrial level. After hot pressing, the GLC with ultralow content (170 to 350 ppm) can be uniformly dispersed and tightly embedded within the copper matrix. A remarkable thermal conductivity enhancement efficiency of 85% and enhanced thermal conductivity (439 W m−1 K−1), accompanied by the higher wear resistance, can be obtained in our GLC reinforced copper matrix composites. In actual arc ablation performance measurement, the breakdown strength and relative arc ablation resistance of GLC/Cu composites can be significantly improved by 106.5% and 33.3% than pure copper, respectively, demonstrating GLC/Cu composites a promising candidate for application as high voltage electrical contacts.

In virtue of its excellent performance and abundant surface terminations, MXenes, a newly emerged 2D materials, greatly exhibit promising applications in many fields of energy storage and electromagnetic shielding. Ti3C2, a member of MXenes, is widely investigated in recent years. However, lack for attention in thermal property and corrosion behavior. Here, Copper matrix composites were prepared by Spark Plasma Sintering, in which TiC and few-layer Ti3C2 nanosheets as filler. The results exhibit corrosion resistance of the Ti3C2/Cu composites were improved compared to TiC/Cu composites, benefiting from outstanding electrical conductivity and easily oxidized property of Ti3C2. However, the thermal conductivity of Ti3C2/Cu composite with the content of 2 wt% Ti3C2 improves about 15% compared to TiC/Cu composites with same content, resulting from the low inherent thermal conductivity of filler and lattice mismatch between copper and filler. Moreover, the electrical resistance of Ti3C2/Cu composites increases about 100% with the content of 2 wt% Ti3C2 at interfacial contact resistance measurement compared with pure Cu. Meanwhile, the anti-corrosion performance of the Ti3C2/Cu composites was improved over pure Cu. This work will broaden appliance field of Ti3C2 and lay the foundation for the future research.

Background Previous studies have implicated reduced brain-derived neurotrophic factor (BDNF) expression and BDNF-TrkB receptor signaling as well as microglial activation and neuroinflammation in poststroke depression (PSD). However, the contributions of microglial BDNF-TrkB signaling to PSD pathogenesis are unclear. Material/Methods We compared depression-like behaviors as well as neuronal and microglial BDNF and TrkB expression levels in the amygdala, a critical mood-relating limbic structure, in rat models of stroke, depression, and PSD. Depression-like behaviors were assessed using the sucrose preference test, open-field test, and weight measurements, while immunofluorescence double staining was employed to estimate BDNF and TrkB expression by CD11b-positive amygdala microglia and NeuN-positive amygdala neuron. Another group of PSD model rats were examined following daily intracerebroventricular injection of proBDNF, tissue plasminogen activator (t-PA), or normal saline (NS) for 7 days starting 4 weeks after chronic unpredictable mild stress (CUMS). Results The numbers of BDNF/CD11b- and TrkB/CD11b-immunofluorescence-positive cells were lowest in the PSD group at 4 and 8 weeks after CUMS (P0.05). Injection of t-PA increased BDNF/CD11b- and TrkB/CD11b-positive cells in the amygdala of PSD rats and normalized behavior compared with NS or proBDNF injection (P

Tungsten copper (WCu) composite has been widely applied in the fields of electrical contacts, heat exchanger and electronic packing materials, due to its high melting point, high hardness of tungsten (W) as well as superior electrical and thermal conductivities of copper (Cu). However, the ease of high-temperature arc ablation hinders the practical application of WCu in high-voltage environment. Herein, we devise an in-situ wrapping strategy to grow graphene over Cu particles for preparing high-performance WCu composite via thermal chemical vapor deposition (CVD). Distinct from the traditional graphene wrappings, our thermal CVD-enabled low-defect graphene achieves not only its uniform dispersion in the matrix but also strong interface affinity with W particles, thus endowing the composite with desirable mechanical properties and excellent electrical conductivity. Particularly, the wear rate of our sample is approximately 76% lower compared to that of WCu. Moreover, both the arc ablation resistance and electrical conductivity properties of our sample are significantly improved due to the in-situ thermal CVD growth of graphene.

Copper powder has broad applications in the powder metallurgy, heat exchanger, and electronic industries due to its intrinsically high electrical and thermal conductivities. However, the ease of formation of surface oxide or patina layer raises difficulty of storage and handling of copper powder, particularly in the case of Cu microparticles. Here, we developed a thermal chemical vapor deposition chemical vapor deposition (CVD) process for large-scale synthesis of graphene coatings on Cu microparticles, which importantly can remain monodisperse without aggregation after graphene growth at high temperature by using removal spacers. Compared to other protective coating methods, the intrinsic electrical and thermal properties of Cu powder would not be degraded by uniform growth of low defect few-layer graphene on each particle surface. As a result, when the anticorrosion performance test was carried out by immersing the samples in Cu etchant, the corrosion rate of graphene/Cu microparticles was significantly improved (ca three times slower) compared to that of pristine Cu powder, also showing a comparable anticorrosion ability to commercial CuZn30 alloy.

The steroid hormone ecdysone, which controls insect molting and metamorphosis, is synthesized in the prothoracic gland (PG), and several steroidogenic enzymes that are expressed specifically in the PG are involved in ecdysteroidogenesis. In this study, we identified new regulators that are involved in the transcriptional control of the silkworm steroidogenic enzyme genes. In silico analysis predicted several potential cis-regulatory elements (CREs) for the homeodomain transcription factors Antennapedia (Antp) and POU-M2 in the proximal promoters of steroidogenic enzyme genes. Antp and POU-M2 are expressed dynamically in the PG during larval development, and their overexpression in silkworm embryo-derived (BmE) cells induced the expression of steroidogenic enzyme genes. Importantly, luciferase reporter analyses, electrophoretic mobility shift assays, and chromatin immunoprecipitation assays revealed that Antp and POU-M2 promote the transcription of the silkworm steroidogenic enzyme gene Phantom (Phm) by binding directly to specific motifs within overlapping CREs in the Phm promoter. Mutations of these CREs in the Phm promoter suppressed the transcriptional activities of both Antp and POU-M2 in BmE cells and decreased the activities of mutated Phm promoters in the silkworm PG. In addition, pulldown and co-immunoprecipitation assays demonstrated that Antp can interact with POU-M2. Moreover, RNA interference-mediated down-regulation of either Antp or POU-M2 during silkworm wandering not only decreased the ecdysone titer but also led to the failure of metamorphosis. In summary, our results suggest that Antp and POU-M2 coordinate the transcription of the silkworm Phm gene directly, indicating new roles for homeodomain proteins in regulating insect ecdysteroidogenesis.

Cordycepin, an adenosine analogue, has been reported to improve cognitive function. Important roles on learning and memory of adenosine and its receptors, such as adenosine A1 and A2A receptors (A1R and A2AR), also have been shown. Therefore, we assume that the improvement of learning and memory induced by cordycepin is likely related to hippocampal adenosine content and adenosine receptor density. Here we investigated the effects of cordycepin on the short-term spatial memory by using a spontaneous alternation behavior (SAB) test in Y-maze, and then examined hippocampal adenosine content and A1R and A2AR densities. We found that orally administrated cordycepin (at dosages of 5 and 10mg/kg twice daily for three weeks) significantly increased the percent of relative alternation of mice in SAB but not altered body weight, hippocampus weight and hippocampal adenosine content. Furthermore, cordycepin decreased A2AR density in hippocampal subareas; however, cordycepin only reduced the A1R density in DG but not CA1 or CA3 region. Our results suggest that cordycepin exerts a nootropic role possibly through modulating A2AR density of hippocampus, which further support the concept that it is mostly A2AR rather than A1R to control the adaptive processes of memory performance. These findings would be helpful to provide a new window into the pharmacological properties of cordycepin for cognitive promotion.

In-situ and ex-situ methods were applied to modify silica particles in order to investigate their effects on the reinforcement of silicone rubber. Surface area and pore analyzer, laser particle size analyzer, Fourier-transform infrared spectroscopy (FTIR), contact-angle instrument, and transmission electron microscope (TEM) were utilized to investigate the structure and properties of the modified silica particles. Dynamic mechanical thermal analyzer (DMTA) was employed to characterize the vulcanizing behavior and mechanical properties of the composites. Thermogravimetric analysis (TGA) was performed to test the thermal stability of the composites. FTIR and contact angle analysis indicated that silica particles were successfully modified by these two methods. The BET surface area and TEM results reflected that in-situ modification was more beneficial to preparing silica particles with irregular shape and higher BET surface area in comparison with ex-situ modification. The DMTA and TGA data revealed that compared with ex-situ modification, the in-situ modification produced positive influence on the reinforcement of silicone rubber. (C) 2014 Elsevier Ltd. All rights reserved.

Porcine circovirus type 2 (PCV2) is a causative agent for PCV-associated disease. To analyze the role of the genomic nucleotide deletion in PCV2 replication, four mutant infectious clones of single nucleotide deletion within ORF2 Δ1376 PCV2, Δ1377 PCV2, Δ1378 PCV2, and Δ1379 PCV2, were constructed by the Dpn I site-directed mutagenesis. These mutants were rescued and verified by indirect immunoinfluscent assay (IFA) on the transfected PK15 cells. The data showed that only infectious clone Δ1376 PCV2 can successfully generate infectious virions, indicating that the nucleotide 1376G within ORF2 is not essential for PCV2 replication. The ability of virus multiplication revealed that virus titer of Δ1376 PCV2 was approximately 10 folds more than that of its parent virus. The proinflammatory factors analysis demonstrated that splenic transcripts and serum concentration of Interleukin-6 (IL-6) in Δ1376 PCV2-infected mice are higher than those in its parent PCV2-infected mice. Our data suggested that the replication ability of PCV2 with the nucleotide 1376G deleted within ORF2 was improved and the mRNA transcription and protein expression of IL-6 were strengthened.

Crystalline boron nanowires (BNWs) have been grown on the entire surface of diamond powders by a solid solid reaction approach. A series of analysis technique were employed to investigate the as grown BNWs. The as grown BNWs are in length of several micron meters with the diameter ranging from 20-200 nm. And the BNVVs crystalline structure is identified to be tetragonal structure. Systematic analyses reveal that the growth models such as classic VLS (vapor-liquid-solid) model are not applicable to explain this kind of BNW's growth mechanism. Hereby, an extended VLS model is proposed which can perfectly interpret the BNW's growth process on diamond surface and match experiment results very well. (C) 2013 Elsevier EN. All rights reserved

The present study provides an efficient approach for nano-functionalization of diamond powders. Boron nanostructure can be grown on diamond particle entire surface by a simple heat-treatment process. After treatment, various boron nanoforms were grown on the diamond particle surface at different processing temperature. High-density boron nanowires (BNVVs) grow on the diamond particle entire surface at 1333 K, while nanopillars cover diamond powders when the heat treatment process is performed at 1393 K. The influence of the pretreatment temperature on the microstructure and thermal conductivity of Cu/diamond composites were investigated. Cu/diamond composites with high thermal conductivity of 670W (mK)(-1) was obtained, which was achieved by the formation of large number of nanowires and nanopillars on the diamond particle surface. (C) 2013 Elsevier B.V. All rights reserved.

Zinc oxide (ZnO) nanorods were synthesized using a modified wet chemical method. Poly(vinylidene fluoride-co-hexafluoropropylene), P(VDF-HFP), nanocomposites with different ZnO nanorods loadings were prepared via a solution blend route. Field emission scanning electron microscopic (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) were used to investigate the structure and morphology of the nanocomposites. XRD and FTIR data indicate that the incorporation of ZnO nanorods promote the crystalline structure transformation of P(VDF-HFP). As the content of ZnO nanorods increases, the β phase structure increases while the α phase decreases. In addition, the dielectric properties of the P(VDF-HFP) and its composites were systematically studied. Open image in new window

Multidrug resistance (MDR) is one of the major reasons for the failure of cancer chemotherapy. A newly reported liposome carrier, propylene glycol liposomes (EPI-PG-liposomes) were made to load epirubicin (EPI) which enhanced EPI absorption in MDR tumor cells to overcome the drug resistance. MDA-MB 435 and their mutant resistant (MDA-MB 435/ADR) cells were used to examine the cellular uptake and P-gp function in vitro for EPI-PG-liposomes by fluorescence microscopy and FCM, respectively. Mammary tumor model was also established to investigate the tumor growth inhibition and pharmacodynamics of EPI-PG-liposomes in vivo. Morphology evaluation showed that EPI-PG-liposomes had a homogeneous spherical shape with an average diameter of 182 nm. Based on cell viability assay, fluorescent microscopy examination, and EPI uptake assay, EPI-PG-liposomes exhibited an effective growth inhibition not only in MDA-MB-435 cells, but also in MDA-MB 435/ADR cells. EPI-PG-liposomes have high permeability not only on tumor cell membrane, but also on cell nucleus membrane. P-gp function assay showed that the anticancer action of EPI-PG-liposomes was not related to P-gp efflux pump, suggesting that PG-liposomes would not affect the normal physiological functions of membrane proteins. EPI-PG-liposomes also showed a better antitumor efficacy compared to EPI solution alone. With high entrapment efficiency, spherical morphology and effective inhibition on MDR cancer cells, EPI-PG-liposomes may represent a better chemotherapeutic vectors for cancer targeted therapy.

While North America and Europe have been recovering from acidification, China is experiencing impacts of acid deposition. The Taihu region is a seriously impacted area by acid rain in China, with the average rainfall pH < 5. However, the acid neutralizing capacity (ANC) and pH of Taihu Lake have significantly increased over the past 60 years (p < 0.05). Analyses showed that watershed neutralization by carbonates and in-lake alkalinization by algae activities were the two major reactions responsible for the increase. In the Taihu basin, the dominant carbonate bedrocks are the major source of base cations (particularly Ca2+ and Mg2+) and act as the acidification buffer. In addition, our field measurements across the lake showed that the pH values were significantly higher in algal bloom waters than in areas without blooms. This observation was further supported by our statistical analysis showing that the Taihu ANC and pH were significantly correlated with the chlorophyll increase (p < 0.05; 1985–2015). How...

Characterization and anti-tumor activity of chemical conjugation of doxorubicin (DOX) in polymeric micelles were investigated. Polymeric micelles with chemical conjugation of doxorubicin (DOX-P) were prepared. Succinic anhydride activated pluronic F68 was first synthesized and the primary amine group in doxorubicin was conjugated to the terminal carboxyl of pluronic F68 via a amide. The resulting polymeric micelles in aqueous solution were characterized by measurement of size, ξ-potential, drug loading and critical micelle concentration. From characterization results, DOX-P micelles had superiorities over physically-loaded DOX micelles in loading efficiency, diameter and CMC value. From drug release experiment in vitro, DOX-P micelles reached a sustained release profile for DOX. The cytotoxic activity of the micelles against A549/DOX cells was greater than free DOX. Fluorescence microscope observation and flow cytometry analysis supported the enhanced cellular uptake of the micelles. From A549/DOX cells experiments, DOX-P micelles could enhance DOX anti-tumor activity and circumvent the multi-drug resistance (MDR) of A549/DOX cells. With low CMC value, high loading efficiency, nanometer diameter, good penetration ability and controlled release behaviour, DOX-P micelles might be developed as a new cancer targeted delivery system.

Gas-filled phospholipid-based ultrasonic microbubbles (PUMs) are widely used in diagnostic imaging. The micro- or nanoparticle size and the physiochemical nature of shell provide the potential for a new way to improve pulmonary absorption for peptides and proteins.Male Sprague-Dawley rats were fasted for 12 h. Then insulin solution and insulin-PUM mixture solution were administered by intratracheal instillation. The hypoglycemic effect was observed to evaluate insulin absorption after lung administration. Fluorescein isothiocyanate-dextran (molecular mass, 4 kDa) was used as the index of evaluating drug alveolar deposition and absorption by visualization techniques.Administration of insulin solution containing PUMs significantly reduced the blood glucose levels of Sprague-Dawley rats, compared with administration of insulin-only solution. The minimum reductions of the blood glucose concentration produced by insulin solution containing PUMs and by an insulin-only solution reached 60.81% and 34.60% of the initial glucose levels, respectively, and their bioavailabilities relative to subcutaneous injection were 48.58% and 29.09%, respectively. Histopathological study of the lung showed no changes in the morphology of the pulmonary alveoli after administration to these drugs. Only a slight inflammatory cell infiltration in the alveoli could be found in some rats.These results suggested that PUMs might be used as an effective way to improve pulmonary absorption for peptides and proteins.

Polymeric compounds are of great interest as corrosion inhibitors in acidic environment due to their inherent stability. Polymeric film is effectively used for the protection of metals partly owing to their capacity to act as a physical barrier between the metal surface and the corrosive environment. In this paper, a cation polyelectrolyte inhibitor (Quaternary Polyethyleneimine, QPEI) was prepared. The quality and inhibition efficiency of QPEI self-adsorbed films were studied by polarization curve and electrochemical impedance spectroscopy, respectively. The compositions and morphologies of the polymer film on the steel surface were examined with the aids of SEM and XPS, respectively. The results showed that QPEI could greatly retard the corrosion of iron in sulfuric acid, which was attributed mainly to the protective QPEI film formed on the surface. Meanwhile, the inhibition of QPEI could be supposed as a mixed process, in which both cathodic and anodic corrosions were simultaneously restrained. Based on the results of XPS and SEM, it could be evidenced that the QPEI can form a protective polymer layer on the metal surface by adsorption.

A novel anodization which is environmentally friendly,low voltage and 1ow energy consumption was developed to improve corrosion resistance of AZ3l magnesium alloy．The corrosion resistance of the anodic films was studied by electrochemical impedance spectroscopy(EIS) and potentiodynamic polarization techniques．The microstructure and compositions of films were examined bv SEM, XPS and XRD．A new kind of organic additive used in the electrolyte is friendly to the environment．The compact, intact and uniform coating with high hardness can be prepared on AZ31 magnesium alloy by the environmentally friendly anodization, which enhances the corosion resistance 0f AZ31 Mg alloy significantly.

H β-zeolite was synthesized using tetraethyl ammonium hydroxide as the template pharmaceutical and microwave radiation as the heat source. The synthesized samples were characterized by x-ray diffraction, BET, and NH3-TPD. The effects of the sol composition and the radiation temperature on the relative crystallinity were studied. The results showed that the relative crystallinity, special surface area, pore volume, and surface acidity of the H β-zeolite microwave synthesized were higher than the industrial product with synthesized with the conventional hydrothermal synthesis method. Etherification activities were evaluated in the minitype fix-bed reactor, and the yields of etherification production were higher than that of industrial samples.

Correction for ‘High quality graphene films with a clean surface prepared by an UV/ozone assisted transfer process’ by Hongyan Sun et al., J. Mater. Chem. C, 2017, 5, 1880–1884.

A superhydrophobic surface was prepared on aluminum substrate. Anodization and low-temperature plasma treatment were used to create micro-nano-structure and subsequently trichlorooctadecyl-silane modified the rough surface. The result shows that the water static contact of the aluminum surface after anodization and modification by trichlorooctadecyl-silane reaches to 152.1°. A rougher surface with some micro-nano-pores and small mastoids along the edges of pores was generated when low-temperature plasma treatment was applied to anodized aluminum film, resulting in water static contact angle up to 157.8°.

Characterization and antitumor activity of basic fibroblast growth factor-mediated active targeting doxorubicin microbubbles (bFGF-DOX-MB) were investigated. Pluronic F68 with chemical conjugation of doxorubicin (DOX-P) and peptide KRTGQYKLC-conjugated DSPE-PEG2000 were prepared. bFGF-DOX-MB had a normal distribution of particle size, with average particle size of 2.7 μm. Using A549 mouse model, bFGF-DOX-MB combined ultrasound showed the best inhibition effect on tumor volume growth among all the test groups. Similar conclusion was obtained from experimental measurements of tumor weight change and blood cell count. From the results, chemotherapeutic drug inhibition on tumor growth could be enhanced by local ultrasound combined with active targeting bFGF-DOX-MB, which might provide a potential application for ultrasound-mediated chemotherapy.

Experiments in vitro and in vivo were designed to investigate tumor growth inhibition of chemotherapeutics-loaded liposomes enhanced by acoustic cavitation. Doxorubicin-loaded liposomes (DOX liposomes) were used in experiments to investigate acoustic cavitation mediated effects on cell viability and chemotherapeutic function. The influence of lingering sensitive period after acoustic cavitation on tumor inhibition was also investigated. Animal experiment was carried out to verify the practicability of this technique in vivo. From experiment results, blank phospholipid-based microbubbles (PBM) combined with ultrasound (US) at intensity below 0.3 W/cm² could produce acoustic cavitation which maintained cell viability at high level. Compared with DOX solution, DOX liposomes combined with acoustic cavitation exerted effective tumor inhibition in vitro and in vivo. The lingering sensitive period after acoustic cavitation could also enhance the susceptibility of tumor to chemotherapeutic drugs. DOX liposomes could also exert certain tumor inhibition under preliminary acoustic cavitation. Acoustic cavitation could enhance the absorption efficiency of DOX liposomes, which could be used to reduce DOX adverse effect on normal organs in clinical chemotherapy.

Polymeric nanoparticles are widely used as targeted carriers for biomacromolecules. In this paper, modified gelatin nanoparticles were prepared and their feasibility as insulin pulmonary administration system was investigated. D: ,L: -glyceraldehyde and poloxamer 188 were used for gelatin nanoparticle preparation. Novel water-in-water emulsion technique was used to prepare insulin-loaded nanoparticles. Morphological examination of insulin-loaded nanoparticles was carried out using scanning electron microscopy (SEM). Intratracheal instillation of insulin-loaded nanoparticles was performed to evaluate animal hypoglycemic effect. With fluorescence labeling of insulin, alveolar deposition and absorption of insulin-loaded nanoparticles were investigated. Histological changes in the lung were also observed to evaluate the safety. From the micromorphology observation, insulin-loaded nanoparticles under gelatin-poloxamer 188 ratio at 1:1 showed smooth and uniform surface, with average particle size 250 nm and Zeta potential -21.1 mV. From animal experiment, insulin-loaded nanoparticles under gelatin-poloxamer 188 ratio at 1:1 promoted insulin pulmonary absorption effectively and showed good relative pharmacological bioavailability. Proved by alveolar deposition result, FITC-insulin-loaded nanoparticle group was characterized by an acute and rapid hypoglycemic effect. In addition, nanoparticles could guarantee the safety of lung by reducing insulin deposition in lung. A transient weak inflammatory response was observed at 1 day after administration. With good physical characterization, high bioavailability, fast and stable hypoglycemic effect, insulin-loaded nanoparticles might be developed as a novel insulin pulmonary system for diabetes therapy.