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To explore the influence of deformation temperature on the tensile and microstructure of high-strength Al alloy, pre-aged AA7075 sheets were processed by cryorolling and room temperature rolling. Hardness and tensile tests examined the mechanical properties of AA7075. The microstructures of AA7075 under different rolling conditions were analyzed by scanning electron microscopy, optical microscopy, x-ray diffraction, electron backscatter diffraction and transmission electron microscope. The results show that the ultimate tensile strength and hardness of cryorolled AA7075 are 672.6 MPa and 226.6 HV, respectively. When the rolling reduction rate reaches 60%, the cryorolled AA7075 remains great ductility of 5.7%. The cryorolling can effectively result in higher dislocation densities, thus improving the strength of the AA7075 sheets. Meanwhile, the cryorolled AA7075 after pre-aging can avoid the occurrence of shear bands and microcracks to improve the material's ductility. [ABSTRACT FROM AUTHOR]

The strength and extent of elongation of AA2024 sheets should be improved to realize the fabrication of lightweight components. We prepared high-performance AA2024 strips following a combination of (low-temperature pre-aging + cryorolling + aging) processes and studied their mechanical properties and microstructures. The results showed that the ultimate tensile strength of the material prepared by this process reached 631 MPa, and 10% elongation could be achieved. The microstructure reveals that the process of pre-aging can significantly improve the dislocation density (~ 47.5%) after cryorolling and then improve the strength of the AA2024 sheets following the dislocation strengthening mechanism. It is also found that the cryorolled AA2024 sheets exhibit the γ -fiber texture, similar to asymmetric rolling. Finally, we calculated the yield strength increment of the material and discussed its strengthening source. [ABSTRACT FROM AUTHOR]

The objective of this study is to develop a new hepatitis B surface antigen (HBsAg) delivery system by coating soluble microneedle arrays with mannose-modified PLGA nanoparticles (MNPs). MNPs of different sizes were synthesized. The effects these nanoparticles on the maturation of dendritic cells were studied by flow cytometry. HBsAg-containing MNPs (HBsAg/MNPs) of the appropriate sizes were coated into water-soluble microneedle arrays. The in vitro characteristics of microneedles arrays and the immune responses after subcutaneous administration in mice were studied. The results showed that PLGA nanoparticles with an average size of about 800 nm showed the most significant effects in stimulating the maturation of dendritic cells. In the water-soluble microneedle array, the targeted PLGA nanoparticles containing HBsAg were distributed discretely with a maximum distribution height of about 280 μm with a drug load of 0.98 ± 0.05 μg/mg. The drug-containing microneedle arrays exhibited excellent mechanical properties and improved biosafety. The results of immune responses in vivo showed that the subcutaneous administration of the microneedle arrays induced the proliferation of splenocyte, secreted specific IL-12 and IFN-γ, and promote the production of IgG in mice. This study verifies the feasibility of soluble composited microneedles administration in hepatitis B immunization, and provides new ideas for the development and application of non-injectable vaccine delivery systems. [ABSTRACT FROM AUTHOR]

In this paper a dynamical system model is proposed for solving the split convex feasibility problem. Under mild conditions, it is shown that the proposed dynamical system globally converges to a solution of the split convex feasibility problem. An exponential convergence is obtained provided that the bounded linear regularity property is satisfied. The validity and transient behavior of the dynamical system is demonstrated by several numerical examples. The method proposed in this paper can be regarded as not only a continuous version but also an interior version of the known CQ-method for solving the split convex feasibility problem. [ABSTRACT FROM AUTHOR]

The application of surfactant or surfactant-assisted media to grow polyoxometalate (POM)-based MOFs (POMOFs) is extremely scarce. In this work, for the first time, we use water-polyethylene glycol (PEG) 400 mixed media to synthesize two new crystalline POM-pillared three-dimensional porous arrays, [Co7(Trz)12(H2O)8][HPX12O40(VO)2]·12H2O (X = Mo for Co-PMo and X = W for Co-PW, Trz = 1,2,4-triazole). By employing a simple sonication-driven functionalization strategy, Co-PMo/CNTs (PCNT-n) nanocomposites with increased effective sites, enhanced specific surface area and excellent conductivity are fabricated. The resulting PCNT-2 nanocomposite shows an excellent reversible capacity of 820 mA h g−1 after 100 cycles and outstanding rate capability as an anode for lithium batteries. After the initial decay, the PCNT-2 electrode can bear a current density of 2000 mA g−1 over 450 cycles without obvious capacity loss. Meanwhile, the mechanism of lithium storage in PCNT-2 is discussed using X-ray photoelectron spectroscopy (XPS). Moreover, the PCNT-2 nanocomposite exhibits the hybrid behavior of battery and supercapacitor according to the electrochemical kinetic analyses. This might open new avenues for the design of crystalline POM-based materials or their nanocomposites to achieve high-performance energy storage. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to develop a novel formulation of oleanolic acid (OA) solid dispersion (SD), using leucine (Leu) as the carrier to improve OA oral bioavailability. Methods: The OA‐Leu SD was prepared by solvent evaporation and was evaluated in vitro using differential scanning calorimetry, X‐ray powder diffraction, scanning electron microscopy, flowability, hygroscopicity and dissolution test. The stability of the SD was evaluated using accelerated testing. In vivo pharmacokinetic tests were performed in male Sprague Dawley rats using a liquid chromatography tandem‐mass spectrometry bioanalytical method. Key findings: OA‐Leu SD was successfully prepared, and OA was mostly in an amorphous state. More than 80% of OA could dissolve in OA‐Leu SD in 20 min, while only 13.4% of free OA dissolved. The powder flow of OA‐Leu SD was clearly improved compared with free OA and its moisture absorption was 3.4%. The accelerated testing further demonstrated that SD could maintain OA in an amorphous state at 40 °C for 6 months. OA‐Leu SD showed higher relative oral bioavailability (189.7%) than free OA in rats. Conclusions: Using Leu as a carrier produced a SD with good flowability, low hygroscopicity and high bioavailability. [ABSTRACT FROM AUTHOR]

The launched hepatitis B vaccine could induce powerful antibodies, whereas it failed to improve potent cellular immune responses due to that the Th2-type response-induced aluminum adjuvant was adopted. Here, to target antigen-presenting cells under the epidermis and induce potent cellular and humoral immune responses, mannose-modified poly d,l-lactide-co-glycolic acid (PLGA) was synthesized and nanoparticle (MNP)-loaded hepatitis B surface antigen (HBsAg) protein was prepared. HBsAg could be slowly released and highly presented to lymphocytes which facilitated to produce long-lasting immunity based on characters of PLGA. In vitro uptake test results showed that MNPs could enhance internalization in bone marrow–derived dendritic cells (BMDCs) and RAW 264.7 cells. Subcutaneous delivery of MNPs into mice kept humoral immune and strengthened cellular immune responses. Experimental results indicated that MNPs showed significantly modified properties compared with parental PLGA nanoparticles. Thus, the obtained MNPs could be a promising vehicle for hepatitis B vaccine delivery. [ABSTRACT FROM AUTHOR]

Background: Adiponectin (ADP) polymorphisms associated with diabetes mellitus in several populations. However, no previous studies have investigated its association with diabetic peripheral neuropathy (DPN). Our study examined the association between ADP-linked SNPs and DPN susceptibility. Methods: We randomly recruited 160 diabetes mellitus (DM) patients and 80 healthy individuals. Results: The C allele of rs3821799 increased DPN susceptibility. In normal individuals, GG of rs3774261 carriers had 7.1 times higher DPN susceptibility than AA carriers. The haplotype analyzes indicated CGG might increase DPN susceptibility. Conclusion: Our study demonstrated that ADP gene polymorphisms are associated with the susceptibility to DPN. [ABSTRACT FROM AUTHOR]

Objectives: To search for mutations in the Frizzled-4 gene (FZD4) in Chinese patients with familial exudative vitreoretinopathy (FEVR) and to delineate the mutation- associated clinical features. Methods: Forty-eight Chinese patients with FEVR and 100 unrelated control subjects were recruited and had complete ophthalmic examinations performed. The coding regions of FZD4 were screened for mutations by polymerase chain reaction and direct sequencing. Multiple sequence alignment was conducted to evaluate the conservation of residues among different FZD4 homologs and the human Frizzled family. Genotype-phenotype correlations were also analyzed. Results: Twelve putative disease-causing mutations were identified in total, 9 of which were novel: 1 deletion (P14fsX57), 1 nonsense mutation (S491X), and 7 missense mutations (G22E, E180K, T237R, R253C, F328S, A339T, and D470N). Three reported FZD4 mutations were also detected: H69Y, M105V, and W496X. Remarkably, 2 patients who harbored compound heterozygous mutations (H69Y with E180K orW496X) had amore severe ocular phenotype than carriers of a single H69Y mutation. Conclusions: FZD4 mutations were responsible for FEVR in 15 of 48 Chinese patients (31.3%) in this study, similar to other ethnic groups. This study supports the highly polymorphic nature of FZD4 with a differential mutation profile in the Chinese population. Clinical Relevance: The profile of the mutations obtained in FZD4 further illustrates the complexity of FEVR and provides a better understanding of the genotypephenotype correlations. [ABSTRACT FROM AUTHOR]