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The hardness, conductivity and room temperature tensile test were used to study the properties of the new aluminum alloy aged at 110-140 ℃ for different time.The microstructure of the alloy was observed by transmission microscope (TEM).The results show that the optimum aging process of the new aluminum alloy is aging at 110 ℃ for 24 h.Tensile strength, yield strength and elongation are 808,785 MPa,6.9%, respectively.Aging temperature is the main factor affecting the type, density and size of precipitates.When aged at 110 ℃,the main precipitations are GPⅠ zones,GPⅡ zones and metastable η' phase. After aging at 110 ℃ for a long time (up to 96 h), GPⅠ zones and GPⅡ zones still exist stably.Compared with aging at 110 ℃, the precipitation process accelerates at 140 ℃.After aging at 140 ℃ for 4 h, no GP zone is observed, and the main precipitate phase is η'.After aging at 140 ℃ for 24 h, the main precipitates are η' phase and η phase.

This research has produced Al-Zn-Mg-Cu alloy containing 20%(mass fraction,the same below) alloying elements by the Hot-top semi-continuous DC casting equipment, which has adopted purifying and refining on-line technologies. This alloy has broken the limit of 7000 Al-alloy containing no more than 14% alloying elements. The microstructure and fracture of the alloy were investigated by optical microscopy (OM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM), the temperature of phases transformation was investigated by differential scanning calorimetry (DSC), and the hardness and tensile properties were also tested. The tensile strength, yield strength and elongation of this alloy can be up to 810.3, 799.3MPa and 3.4% by RRA heat-treatment after extrusion. Through the study on the single and tertiary-stage ageing treatment kinetics, the optimum ageing temperature 120℃ is identified and a wider range of aging time can be chosen. Moreover, no other precipitates are found in the alloy containing 16.1%Zn element,and the joint strengthening comes from the undissolved second phase and the ageing precipitation η' phase.

A kind of Al-Zn-Mg-Cu alloy containing 9.6%(mass fraction) Zn element was produced by the Hot-top semi-continuous DC casting technology. The microstructure of the alloy and the temperature of phases transformation were investigated by optical microscopy(OM),transmission electron microscopy(TEM) and differential scanning calorimetry(DSC) respectively.The hardness and tensile properties of the alloy were tested,and the fracture was studied by scanning electron microscopy(SEM).Results show that the as-cast microstructure of this alloy is fine and has less intergranular eutectic phases, with the melting temperature of 473.4℃. Therefore, the homogenization heat-treatment is 465℃/24h. After the homogenization heat-treatment, the grain boundary of the ingot has turned to be intermittent and the phases have dissolved significantly. Besides, the systematic experiments were conducted on the T6 and RRA of this alloy after extrusion. The results show that on the condition of 135℃/12h treatment, the highest hardness is 197.7HBS, and the tensile strength, yield strength, elongation are 727.5, 718.0MPa and 9.3% respectively. On the condition of 120℃/24h+190℃/5min+135℃/3h treatment, the highest hardness is 204.7HBS, and the tensile strength, yield strength, elongation can reach 764.0, 749.0MPa and 7.2% respectively.

Background: For enhancement of drug effectiveness and reduction of drug toxicity, liposomal drugs have been studied in laboratories and clinics for decades. Although the results obtained from in vitro are encouraging, but the results from in vivo tests were not satisfactory. The main reasons for this situation were that we do not have enough information about the way how liposomal particles penetrating into solid tumor tissue, and what happening to the liposome particles after they got into the tumor tissue. In this paper, we are going to report the results from our observations on the way folic acid targeted and non-targeted PEGyl-DSPC liposomal doxorubicin particles penetrate into solid tumor tissue.Methods: Subcutaneous transplanted murine L1210JF solid tumors in mice were used as a model. PEGyl liposomal doxorubicins were injected through tail venue, and tumor tissue samples were collected at special time points. Cryosections were cut and dried by a fl owing of air after mounted on the slides right away. Then the dried cryosections were stained in water systems; the blood vessel cells were stained with green fluorescent FITC labeled antibody against CD31 antigen; the nuclei of the living cells were stained with a blue fluorescent dye DAPI. Since the whole procedure was carried out in aquatic system, the red color fluorescent liposomal doxorubicin particles remain visible under fl uorescence microscope.Results: Both folate conjugated and non-conjugated PEGyl-DSPC liposomal doxorubicin particles were only leaking out from the broken holes of blood vessels with a special direction and spread out for a limited distance, which was similar to the results showed before, in that observation a latex microsphere sample was used as a model.

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Biallelic MYO5B variants have been associated with familial intrahepatic cholestasis (FIC) with low serum gamma-glutamyltransferase (GGT). Intronic or synonymous variants outside of canonical splice sites (hereinafter referred to as noncanonical variants) with uncertain significance were identified in MYO5B posing a challenge in clinical interpretation. This study is aimed at assessing the effects of these variants on premessenger RNA (pre-mRNA) splicing to improve recognition of pathogenic spliceogenic variants in MYO5B and better characterize the MYO5B genetic variation spectrum. Disease-associated MYO5B noncanonical variants were collected from the literature or newly identified low GGT cholestasis patients. In silico splicing predictions were performed to prioritize potential pathogenic variants. Minigene splicing assays were performed to determine their splicing patterns, with confirmation by blood RNA analysis in one case. Eleven (five novel) noncanonical variants with uncertain significance were identified. Minigene splicing assays revealed that three variants (c.2090+3A>T, c.2414+5G>T, and c.613-11G>A) caused complete aberrations, five variants (c.2349A>G/p.(=), c.4221G>A/p.(=), c.1322+5G>A, c.1669-35A>C, and c.3045+3A>T) caused predominant aberrations, and three variants (c.4852+11A>G, c.455+8T>C, and c.2415-6C>G) had no effect on pre-mRNA splicing. Patient-derived RNA analysis showed consistent results. Based on our results, eight variants were reclassified as likely pathogenic and three as likely benign. Combining the clinical features and the above analysis, the diagnosis of MYO5B-associated FIC could be made in three new patients. In conclusion, we characterized the splicing patterns of MYO5B noncanonical variants and suggest that RNA analysis should be routinely included in clinical diagnostics to provide essential evidence for the interpretation of variants. [ABSTRACT FROM AUTHOR]