ISSN 0253-2778

CN 34-1054/N

2021 Vol. 51, No. 2

Invited Reviews
Three-dimensional array materials for electrocatalytic water splitting
Liu Qilong, Xiao Chong
2021, 51(2): 87-102. doi: 10.52396/JUST-2021-0045
Hydrogen energy is considered to be one of the clean energy sources most likely to alternate fossil fuels. The exploration of catalytic materials suitable for electrocatalytic water splitting to produce hydrogen has become an important subject in the field of water electrolysis. Limited to the phenomena of easy stacking of nano-powder materials and poor conductivity during the catalytic reaction, the combination of nano-active materials and conductive substrates to construct three-dimensional (3D) array electrodes with open porous structures has become a research hotspot. This article first summarizes the advantages of 3D array electrodes for water electrolysis, then briefly describes several strategies for improving the catalytic performance of materials, and finally classifies and summarizes the array catalytic materials used for water electrolysis. It is expected to provide reference for the design and synthesis of electrocatalytic materials in the future.
Research Articles: Chemistry
Electrodialysis to concentrate high-salinity solutions: The matching relation between cation- and anion-exchange membranes
YAN Haiyang, LI Wei, WANG Yaoming, WU Liang, NIKONENKO Victor, PISMENSKAYA Natalia, XU Tongwen
2021, 51(2): 103-110. doi: 10.52396/JUST-2021-0044
The effect of the matching relation between the cation and anion exchange membranes on the electrodialysis (ED) concentration performance was investigated through evaluating the salt flux, water flux, the flux ratio of salt to water and the salt content of the ED concentrate. Results indicate that the water uptake of the cation exchange membrane (CEM) is a key factor for the ED concentration performance when the ion exchange capacity of CEM has a feasible value; while for the anion exchange membrane (AEM), the ion permeability maybe is more important compared with the ion exchange capacity and the water uptake for the ED concentration performance. Besides, CEM has a greater significance for the ED concentration performance compared with AEM when both membranes have a relatively high ion permeability.
Synthesis of protected amines from N-hydroxyphthalimide esters via Curtius rearrangement
Xu Ying, Xu Mengyu
2021, 51(2): 111-116. doi: 10.52396/JUST-2021-0029
An efficient and mild method to prepare carbamoyl azides from NHP (N-hydroxyphthalimide) esters and TMSN3 was developed. The structure of carbamoyl azide was confirmed by the X-ray analysis. Corresponding carbamoyl azides were converted into carbamates for isolation. This methodology allows an efficient access to primary, secondary, tertiary alkyl and aryl carbamates. Mechanistic studies reveal that Curtius rearrangement is responsible for the generation of carbamoyl azides.
Research Articles: Life Sciences and Medicine
LncRNA GIMA promotes hepatocarcinoma cell survival via inhibiting ATF4 under metabolic stress
Wang Hong, Luo Jingjing, Wang Chenfeng, Zhang Guang, Mei Yide, Yang Yang
2021, 51(2): 117-128. doi: 10.52396/JUST-2021-0041
Tumor cells are usually under nutrient-deficient microenvironment, a series of adaptive responses are adopted to maintain the cell survival and growth under the metabolic stress. However, the regulatory role of long non-coding RNA (lncRNA) in this process still remains elusive.To explore whether lncRNAs involve in regulating the hepatocarcinoma cell survival under the metabolic stress, GIMA(glucose-deprivation induced modulator of ATF4) was identified as an lncRNA induced by glucose deprivation via the transcriptome sequencing, and the upregulation of GIMA depends on the ATF4 activation under glucose deprivation. The Luciferase assay and the chromatin immunoprecipitation assay proved that GIMA is the transcriptional target gene of ATF4. Furthermore, GIMA promotes the hepatocarcinoma cell survival under glucose deprivation via specifically inhibiting ATF4. Taken together,these results suggest that GIMA may be a new potential target for the hepatocarcinoma treatment.
Effects of alanine-serine-cysteine transporter 2 on proliferation and invasion of hepatocellular carcinoma
Yu Shuqi, Zhang Shitong, Wang Dezheng, Sun Yi, Cheng Meiling, Kan Chen, Ni Fang
2021, 51(2): 129-139. doi: 10.52396/JUST-2021-0033
Metabolic reprogramming is a major feature of tumors, and tumor cells adapt to their glutamine needs by up-regulating the alanine-serine-cysteine transporter 2(ASCT2). It was found that the ASCT2 expression in hepatocellular carcinoma (HCC) tissues was significantly higher than that in normal liver tissues. In addition, the higher expression of ASCT2 in HCC patients was closely associated with poor survival.The knockdown of ASCT2 inhibited the proliferation, clone formation, migration and invasion of HCC cells in vitro.Cell cycle analysis suggested that knockdown of ASCT2 inhibited the proportion of HCC cells in the S phase. In vivo tumorigenic assay confirmed that the knockdown of ASCT2 in HCC cells could significantly inhibit tumor growth.Further studies showed that the knockdown of ASCT2 significantly reduced mitochondrial oxidative phosphorylation(OXPHOS),ATP production,and the phosphorylation level of AKT/S6 in HCC cells.Overall, our results showed that knockdown of ASCT2 could inhibit the malignancy of HCC cells. In addition, the mitochondrial metabolism and phosphorylation level of the AKT/S6 signaling pathway of HCC cells were also inhibited following the ASCT2 inhibition, suggesting that the dysregulated mitochondrial metabolism and abnormal activation of AKT/S6 signaling pathway were closely associated with the HCC progression.
Histone methyltransferase SDG8 in dehydration stress
Sun Xingwang, Chen Lan, Su Yanhua, Ding Yong, Zheng Han
2021, 51(2): 140-146. doi: 10.52396/JUST-2020-0006
The covalent modifications of histone in plants have changed dynamically during the development and adaption to dehydration stress. However, the histone modification enzymes involved in dehydration stress are mostly unknown. Here, we show that the SDG8, responsible for di- and tri-methylation of H3 lysine36, is involved in dehydration stress in Arabidopsis. The expression analysis shows that mutations in SDG8 result in altering a cluster of gene transcripts, including genes in salt, cold, and dehydration stress. Loss-of-function of SDG8 displays faster transpiration, larger stomatal apertures, less sensitivity to the ABA treatment, and decreased tolerance to dehydration stress. Together, our study suggests that SDG8 might be a novel factor involved in the dehydration stress process.
SIPA1L2 as a risk factor implicated in Alzheimer's disease
WEN Canhong, LI Jiarui, CAI Jiahui, TAN Haizhu
2021, 51(2): 147-152. doi: 10.52396/JUST-2021-0008
Alzheimer's disease(AD) is a common neurodegenerative disorder with high heritability. An increasing number of common variants have been found to be associated with AD, but these common variants can only explain a small proportion of the heritability. Theory and practice have shown that rare variants can explain the remaining heritability. We explored rare functional variants that altering susceptibility to AD among 600470 variants in 389 individuals (175 with AD and 214 with cognitively normal). Firstly, after imputing the missing genotypes on the Michigan imputation server, quality control and gene-based annotation were carried out. Secondly, the efficient resampling sequence kernel association test was performed on 311 annotated exonic variants. Finally, the underlying biological interpretations of the identified risk gene were predicted through several bioinformatics tools. The results showed that under the Bonferroni correction, the rare missense variant rs2275303 in SIPA1L2 gene was significantly associated with AD (P=6.00E-04), and its pathogenicity was verified by bioinformatics analysis. SIPA1L2 gene is expected to play an important role in the prevention, diagnosis, prognosis and treatment of AD.
Research Articles: Mathematics
Global dynamics of an SEIQR model with saturation incidence rate and hybrid strategies
Ma Yanli, Chu Zhengqing, Li Hongju
2021, 51(2): 153-163. doi: 10.52396/JUST-2020-1046
An SEIQR epidemic model with the saturation incidence rate and hybrid strategies was proposed, and the stability of the model was analyzed theoretically and numerically. Firstly, the basic reproduction number R0 was derived, which determines whether the disease was extinct or not. Secondly, through LaSalle's invariance principle, it was proved that the disease-free equilibrium is globally asymptotically stable and the disease generally dies out when R0<1. By Routh-Hurwitz criterion theory, it was proved that the disease-free equilibrium is unstable and the unique endemic equilibrium is locally asymptotically stable when R0>1. Thirdly, according to the periodic orbit stability theory and the second additive compound matrix, it was proved that the unique endemic equilibrium is globally asymptotically stable and the disease persists at this endemic equilibrium if it initially exists when R0>1. Finally, some numerical simulations were carried out to illustrate the results.
The asymptotic properties of least square estimators in the linear errors-in-variables regression model with φ-mixing errors
Deng Xin, Tian Chunyu, Ge Meimei, Ye Jing, Ding Yang, Wu Yi
2021, 51(2): 164-172. doi: 10.52396/JUST-2020-0019
The simple linear errors-in-variables (EV) model with φ-mixing random errors was mainly studied. By using the central limit theorem and the Marcinkiewicz-type strong law of large numbers for the φ-mixing sequence, the asymptotic normality of the least square (LS) estimators for the unknown parameters were established under some mild conditions. In addition, based on the strong convergence for weighted sums of φ-mixing random variables, the strong consistency of the LS estimators were obtained. Finally, the simulation study was provided to verify the validity of the theoretical results.