An ultra-high strength aluminum alloy was produced by casting and then extruded to rods. The effect of heat treatment on the microstructure and mechanical properties of the alloy was investigated. After single ageing ...An ultra-high strength aluminum alloy was produced by casting and then extruded to rods. The effect of heat treatment on the microstructure and mechanical properties of the alloy was investigated. After single ageing （120℃, 24 h）, the tensile strength was 812.4 MPa and the elongation was 6.2%. After retrogression reaging （RRA）, the tensile strength was 751.2 MPa and the elongation was 6.4%. The strengthening mechanism is considered as fine grain strengthening, substructure strengthening and dispersion strengthening by Al3（Sc, Zr）.展开更多
To achieve sexual reproduction, flowering plants have evolved a unique double fertilization system that is distinct from animals. Pollen, the male gametophyte of angiosperms, contains two immobile sperm cells and func...To achieve sexual reproduction, flowering plants have evolved a unique double fertilization system that is distinct from animals. Pollen, the male gametophyte of angiosperms, contains two immobile sperm cells and functions as a vehicle for male-female interconnection. Upon landing on the stigma of a flower, it immediately germinates and forms a highly polarized and rapidly growing pollen tube, which delivers the sperm cells to the female gametes embedded deep in the ovules （Dresselhaus et al., 2016）.展开更多
Viral isolation in cell cultures has been regarded for decades as the“gold standard”for the laboratory diagnosis of influenza viral infections.Not all viral strains could be isolated from clinical samples.This study...Viral isolation in cell cultures has been regarded for decades as the“gold standard”for the laboratory diagnosis of influenza viral infections.Not all viral strains could be isolated from clinical samples.This study aimed to quantify the viral load in the samples before isolation to save working time and improve working efficiency.Four hundred samples from patients with influenza-like cases were confirmed pdmH1N1 positive(200 cases)and B Victoria(BV)positive(200 cases)by whole-genome sequencing and analyzed by ddPCR for viral load in samples before isolation,and isolation results were verified by hemagglutination(HA)assay and hemagglutination-inhibition(HI)tests.Probit regression analysis was used to calculate the isolation viral load limit with a 95%probability level by SPSS 19.0 software.The results showed that the isolation limit of viral load was 4.9×10^(4)(95%CI:2.5×10^(4)–9.0×10^(4))copies/mL for pdmH1N1 and 1.9×10^(4)(95%CI:7.8×103–3.6×10^(4))copies/mL for BV.The isolation rate of clinical samples is positively correlated with the viral load in clinical samples,which can be used for viral culture,providing important guidance for daily work.展开更多
基金the National Key Fundamental Research and Development Program of China(No.2005CB623706).
文摘An ultra-high strength aluminum alloy was produced by casting and then extruded to rods. The effect of heat treatment on the microstructure and mechanical properties of the alloy was investigated. After single ageing （120℃, 24 h）, the tensile strength was 812.4 MPa and the elongation was 6.2%. After retrogression reaging （RRA）, the tensile strength was 751.2 MPa and the elongation was 6.4%. The strengthening mechanism is considered as fine grain strengthening, substructure strengthening and dispersion strengthening by Al3（Sc, Zr）.
基金Research in the Wang lab was supported by the National Natural Science Foundation of China （31770196 and 31570001）, Natural Science Foundation of Guangdong Province （2016A030313401）, and Natural Science Foundation of Guangzhou （201707010024）.
文摘To achieve sexual reproduction, flowering plants have evolved a unique double fertilization system that is distinct from animals. Pollen, the male gametophyte of angiosperms, contains two immobile sperm cells and functions as a vehicle for male-female interconnection. Upon landing on the stigma of a flower, it immediately germinates and forms a highly polarized and rapidly growing pollen tube, which delivers the sperm cells to the female gametes embedded deep in the ovules （Dresselhaus et al., 2016）.
基金Capital Health Development and Research of Special(2022‐1G‐3014)Beijing Science and Technology Planning Project of Beijing Science and Technology Commission(Z211100002521015 and Z211100002521019)+1 种基金National Key R&D Program of China(2021ZD0114100,2021ZD0114103)Cooperation Research Project(2020‐jk‐cd‐026).
文摘Viral isolation in cell cultures has been regarded for decades as the“gold standard”for the laboratory diagnosis of influenza viral infections.Not all viral strains could be isolated from clinical samples.This study aimed to quantify the viral load in the samples before isolation to save working time and improve working efficiency.Four hundred samples from patients with influenza-like cases were confirmed pdmH1N1 positive(200 cases)and B Victoria(BV)positive(200 cases)by whole-genome sequencing and analyzed by ddPCR for viral load in samples before isolation,and isolation results were verified by hemagglutination(HA)assay and hemagglutination-inhibition(HI)tests.Probit regression analysis was used to calculate the isolation viral load limit with a 95%probability level by SPSS 19.0 software.The results showed that the isolation limit of viral load was 4.9×10^(4)(95%CI:2.5×10^(4)–9.0×10^(4))copies/mL for pdmH1N1 and 1.9×10^(4)(95%CI:7.8×103–3.6×10^(4))copies/mL for BV.The isolation rate of clinical samples is positively correlated with the viral load in clinical samples,which can be used for viral culture,providing important guidance for daily work.
