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1. chinaXiv:202108.00007 [pdf]

Size- and leaf age-dependent effects on the photosynthetic and physiological responses of Artemisia ordosica to drought stress

WANG Chunyuan; YU Minghan; DING Guodong; GAO Guanglei; ZHANG Linlin; HE Yingying; LIU Wei
Subjects: Geosciences >> Geography

Drought is one of the most significant natural disasters in the arid and semi-arid areas of China. Populations or plant organs often differ in their responses to drought and other adversities at different growth stages. At present, little is known about the size- and leaf age-dependent differences in the mechanisms of shrub-related drought resistance in the deserts of China. Here, we evaluated the photosynthetic and physiological responses of Artemisia ordosica Krasch. to drought stress using a field experiment in Mu Us Sandy Land, Ningxia Hui Autonomous Region, China in 2018. Rainfall was manipulated by installing outdoor shelters, with four rainfall treatments applied to 12 plots (5 m×5 m). There were four rainfall levels, including a control and rainfall reductions of 30%, 50% and 70%, each with three replications. Taking individual crown size as the dividing basis, we measured the responses of A. ordosica photosynthetic and physiological responses to drought at different growth stages, i.e., large-sized (>0.5 m2) and small-sized (≤0.5 m2) plants. The leaves of A. ordosica were divided into old leaves and young leaves for separate measurement. Results showed that: (1) under drought stress, the transfer efficiency of light energy captured by antenna pigments to the photosystem II (PSII) reaction center decreased, and the heat dissipation capacity increased simultaneously. To resist the photosynthetic system damage caused by drought, A. ordosica enhanced its free radical scavenging capacity by activating its antioxidant enzyme system; and (2) growth stage and leaf age had effects on the reaction of the photosynthetic system to drought. Small A. ordosica plants could not withstand severe drought stress (70% rainfall reduction), whereas large A. ordosica individuals could absorb deep soil water to ensure their survival in severe drought stressed condition. Under 30% and 50% rainfall reduction conditions, young leaves had a greater ability to resist drought than old leaves, whereas the latter were more resistant to severe drought stress. The response of A. ordosica photosynthetic system reflected the trade-off at different growth stages and leaf ages of photosynthetic production under different degrees of drought. This study provides a more comprehensive and systematic perspective for understanding the drought resistance mechanisms of desert plants.

submitted time 2021-08-06 From cooperative journals:《Journal of Arid Land》 Hits2797Downloads220 Comment 0

2. chinaXiv:202010.00034 [pdf]

Application of a new wind driving force model in soil wind erosion area of northern China

ZOU,Xueyong; LI,Huiru; LIU,Wei; WANG,Jingpu; CHENG,Hong; WU,Xiaoxu; ZHANG,Chunlai; KANG,Liqiang
Subjects: Geosciences >> History of Geosciences

The shear stress generated by the wind on the land surface is the driving force that results in the wind erosion of the soil. It is an independent factor influencing soil wind erosion. The factors related to wind erosivity, known as submodels, mainly include the weather factor (WF) in revised wind erosion equation (RWEQ), the erosion submodel (ES) in wind erosion prediction system (WEPS), as well as the drift potential (DP) in wind energy environmental assessment. However, the essential factors of WF and ES contain wind, soil characteristics and surface coverings, which therefore results in the interdependence between WF or ES and other factors (e.g., soil erodible factor) in soil erosion models. Considering that DP is a relative indicator of the wind energy environment and does not have the value of expressing wind to induce shear stress on the surface. Therefore, a new factor is needed to express accurately wind erosivity. Based on the theoretical basis that the soil loss by wind erosion (Q) is proportional to the shear stress of the wind on the soil surface, a new model of wind driving force (WDF) was established, which expresses the potential capacity of wind to drive soil mass in per unit area and a period of time. Through the calculations in the typical area, the WDF, WF and DP are compared and analyzed from the theoretical basis, construction goal, problem-solving ability and typical area application; the spatial distribution of soil wind erosion intensity was concurrently compared with the spatial distributions of the WDF, WF and DP values in the typical area. The results indicate that the WDF is better to reflect the potential capacity of wind erosivity than WF and DP, and that the WDF model is a good model with universal applicability and can be logically incorporated into the soil wind erosion models.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits947Downloads561 Comment 0

3. chinaXiv:202002.00078 [pdf]

Confirmed asymptomatic carrier of SARS-CoV-2

Luo, Sihui; Liu, Wei; Liu, Zhenjun; Zheng, Xueying; Ling, Ping; Ding, Yu; Hong, Changxing; Liu, Zhirong; Liu, Jian; Weng, Jianping
Subjects: Medicine, Pharmacy >> Clinical Medicine

Here we reported a case of asymptomatic carrier of SARS-CoV-2 infection. A 50-year old woman, lived with her husband in Anqing(Anhui, China) with no significant past medical history, travel history to Wuhan or adjacent area, or exposure to wild animals. She took throat swab test for SARS-CoV-2 nucleic acid due to her husband’s close contact with patients who had SARS-CoV-2 infection. Her results were confirmed positive on February 6, 2020. But she did not report elevation of temperature measurement, nor respiratory or gastrointestinal symptoms and her chest CT scan showed no significant abnormalities. She was hospitalized on February 6 and treated with antiviral agents. During her hospitalization, apart from a mild elevation of liver enzymes after 10-day treatment of lopinavir/ritonavir, she was asymptomatic, with her blood cell count, live and renal function largely normal. Her subcutaneous oxygen saturation stayed above 97%. Chest CT scan was repeated on February 11 and 20, and both were negative for signs of viral pneumonia. Notably, a second set of throat swabs and anal swabs were sent to test for SARS-CoV-2 on February 19, and the results were still confirmed positive. This is a confirmed case of asymptomatic carrier of SARS-CoV-2 infection. Her persistent positive findings in both throat and anal swabs suggested the possibility of healthy carrier of the virus, which adds to the difficulty in preventing transmission of the disease.

submitted time 2020-02-28 Hits35079Downloads4221 Comment 0

4. chinaXiv:201711.00152 [pdf]

Synthesis, Crystal Structure, Theoretical Calculations, and Photoluminescent Property of a Mn(II) Complex Assembled by 5-Amino-isophthalic Acid and Phen Ligands

LIU Wei; LI Hui-Ming; YAN Li; WANG Qing-Wei; XU Lei
Subjects: Chemistry >> Physical Chemistry

A coordination polymer [Mn2(ctpt)2(aic)2]n (1, ctpt = 2-(4-chloro-phenyl)-1H-1,3,7,8- tetraaza-cyclopenta[l]phenanthrene, H2aic = 5-amino-isophthalic acid) was hydrothermally designed and synthesized. The complex was characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, and thermogravimetric analysis (TGA). Each Mn(II) atom is linked by the aic ligands with neighbor Mn(II) atoms, forming an infinite one-dimensional (1D) double-chain structure. Complex 1 crystallizes in monoclinic, space group C2/c, with a = 18.23(1), b = 17.27(1), c = 16.69(1) ?, V = 4814.0(7) ?3, C27H16ClMnN5O4, Mr = 564.84, Dc = 1.559 g/cm3, μ(MoKα) = 0.706 mm-1, F(000) = 2296, Z = 8, the final R = 0.0487 and wR = 0.1269 (I > 2σ(I)). The 1D chain structure of complex 1 is stable below 458 ℃. In addition, to elucidate the essential electronic characters of this complex, theoretical calculation analysis of 1 was performed by the PBE0/LANL2DZ method in Gaussian 03 Program.

submitted time 2017-11-05 From cooperative journals:《结构化学》 Hits1812Downloads1003 Comment 0

5. chinaXiv:201705.00516 [pdf]

Mechanical Robust and Self-Healable Supramolecular Hydrogel

Zheng, J [Zheng, Jing][ 1 ]; Xiao, P [Xiao, Peng][ 1 ]; Liu, W [Liu, Wei][ 1 ]; Zhang, JW [Zhang, Jiawei][ 1 ]; Huang, YJ [Huang, Youju][ 1 ]; Chen, T [Chen, Tao][ 1 ]

Development of self-healing polymers with spontaneous self-healing capability and good mechanical performance is highly desired and remains a great challenge. Here, mechanical robust and self-healable supramolecular hydrogels have been fabricated by using

submitted time 2017-05-02 Hits1533Downloads871 Comment 0

6. chinaXiv:201605.01519 [pdf]

Biochemical and structural characterization of a novel ubiquitin-conjugating enzyme E2 from Agrocybe aegeria reveals Ube2w family-specific properties

Qi, Chao; Li, De-Feng; Feng, Lei; Hou, Yanjie; Wang, Da-Cheng; Qi, Chao; Sun, Hui; Liu, Wei
Subjects: Biology >> Biophysics

Ubiquitination is a post-translational modification that is involved in myriad cellar regulation and disease pathways. The ubiquitin-conjugating enzyme (E2) is an important player in the ubiquitin transfer pathway. Although many E2 structures are available, not all E2 families have known structures, and three-dimensional structures from fungal organisms other than yeast are lacking. We report here the crystal structure of UbcA1, which is a novel ubiquitin-conjugating enzyme identified from the edible and medicinal mushroom Agrocybe aegerita and displays potential antitumor properties. The protein belongs to the Ube2w family and shows similar biochemical characteristics to human Ube2w, including monomer-dimer equilibrium in solution, alpha-NH2 ubiquitin-transfer activity and a mechanism to recognize backbone atoms of intrinsically disordered N-termini in substrates. Its structure displays a unique C-terminal conformation with an orientation of helix alpha 3 that is completely different from the reported E2 structures but similar to a recently reported NMR ensemble of Ube2w. A mutagenesis study on this novel enzyme revealed that an intact C-terminus is significant for protein dimerization and enzymatic activity. As the first crystallized full-length protein of this family, UbcA1 may supersede the truncated X-ray structure of Ube2w (PDB entry 2A7L) as the representative structure of the Ube2w family.

submitted time 2016-05-12 Hits2601Downloads1387 Comment 0

7. chinaXiv:201605.01414 [pdf]

Integrative analysis of human protein, function and disease networks

Liu, Wei; Wang, Xiaofan; Wu, Aiping; Wu, Aiping; Wu, Aiping; Wu, Aiping; Pellegrini, Matteo
Subjects: Biology >> Biophysics

Protein-protein interaction (PPI) networks serve as a powerful tool for unraveling protein functions, disease-gene and disease-disease associations. However, a direct strategy for integrating protein interaction, protein function and diseases is still absent. Moreover, the interrelated relationships among these three levels are poorly understood. Here we present a novel systematic method to integrate protein interaction, function, and disease networks. We first identified topological modules in human protein interaction data using the network topological algorithm (NeTA) we previously developed. The resulting modules were then associated with functional terms using Gene Ontology to obtain functional modules. Finally, disease modules were constructed by associating the modules with OMIM and GWAS. We found that most topological modules have cohesive structure, significant pathway annotations and good modularity. Most functional modules (70.6%) fully cover corresponding topological modules, and most disease modules (88.5%) are fully covered by the corresponding functional modules. Furthermore, we identified several protein modules of interest that we describe in detail, which demonstrate the power of our integrative approach. This approach allows us to link genes, and pathways with their corresponding disorders, which may ultimately help us to improve the prevention, diagnosis and treatment of disease.

submitted time 2016-05-12 Hits1929Downloads1051 Comment 0

8. chinaXiv:201605.01342 [pdf]

Functional Characterization of Long Noncoding RNA Lnc_bc060912 in Human Lung Carcinoma Cells

Luo, Huaxia; Sun, Yu; Wei, Guifeng; Luo, Jianjun; Yang, Xinling; Liu, Wei; Chen, Runsheng; Luo, Huaxia; Sun, Yu; Wei, Guifeng; Yang, Xinling; Liu, Wei; Chen, Runsheng; Yang, Xinling; Guo, Mingzhou
Subjects: Biology >> Biophysics >> Biochemistry & Molecular Biology

Long noncoding RNAs (lncRNAs) are pervasively transcribed in the human genome. Recent studies suggest that the involvement of IncRNAs in human diseases could be far more prevalent than previously appreciated. Here we have identified a lncRNA termed Lnc_bc060912 whose expression is increased in human lung and other tumors. Lnc_bc060912 is 1.2 kb in length and is composed of two exons. The expression of Lncbc060912, was repressed by p53. Lnc_bc060912 suppressed cell apoptosis. Using a recently developed method for RNA-pulldown with formaldehyde cross-linking, we found that Lnc_bc060912 interacted With the two DNA damage repair proteins PARP1 and NPM1. Together, these results suggest that Lnc_bc060912, via PARP1 and NPM1, affects cell apoptosis and may play important roles in tumorigenesis and cancer progression.

submitted time 2016-05-11 Hits2023Downloads1242 Comment 0

9. chinaXiv:201605.01284 [pdf]

Transcriptome profiling of esophageal squamous cell carcinoma reveals a long noncoding RNA acting as a tumor suppressor

Wei, Guifeng; Luo, Huaxia; Sun, Yu; Tian, Liqing; Liu, Wei; Liu, Lihui; Luo, Jianjun; Chen, Runsheng; Li, Jiagen; He, Jie
Subjects: Biology >> Biophysics >> Oncology

Esophageal Squamous Cell Carcinoma (ESCC) is among the most common malignant cancers worldwide. In the past, extensive efforts have been made to characterize the involvement of protein-coding genes in ESCC tumorigenesis but few for long noncoding RNAs (lncRNAs). To investigate the transcriptome profile and functional relevance of lncRNAs, we performed an integrative analysis of a customized combined lncRNA-mRNA microarray and RNA-seq data on ESCCs and matched normal tissues. We identified numerous lncRNAs that were differentially expressed between the normal and tumor tissues, termed "ESCC-associated lncRNAs (ESCALs)", of which, the majority displayed restricted expression pattern. Also, a subset of ESCALs appeared to be associated with ESCC patient survival. Gene set enrichment analysis (GSEA) further suggested that over half of the ESCALs were positively- or nelgativelyassociated with metastasis. Among these, we identified a novel nuclear-retained lncRNA, named Epist, which is generally highly expressed in esophagus, and which is down-regulated during ESCC progression. Epist over-expression and knockdown studies further suggest that Epist inhibits the metastasis, acting as a tumor suppressor in ESCC. Collectively, our analysis of the ESCC transcriptome identified the potential tumor suppressing lncRNA Epist, and provided a foundation for future efforts to identify functional lncRNAs for cancerous therapeutic targeting.

submitted time 2016-05-11 Hits2423Downloads1161 Comment 0

10. chinaXiv:201605.01283 [pdf]

Knockdown of ERp44 leads to apoptosis via activation of ER stress in HeLa cells

Chang, Yan; Wu, Yanyun; Ji, Guangju; Liu, Wei
Subjects: Biology >> Biophysics >> Biochemistry & Molecular Biology

ERp44, an endoplasmic reticulum (ER) resident protein, regulates intracellular Ca2+ release and involves in the maturation of many proteins in mammalian cells. In this study, we investigated the effects and mechanism of ERp44 on cell apoptosis by using ERp44 knockdown stable HeLa cell lines. We found that ERp44 knockdown resulted in increases in cell apoptosis rate more than one fold higher than that of control; using serum starvation, caspase-3 protein level was significantly up-regulated in ERp44 knockdown cells compared to the control cells. Furthermore, we demonstrated that in response to serum starvation, the protein levels of CHOP and GRP78 were also largely raised in ERp44 knockdown cells. Moreover, caspase-12 was activated, which suggested cell apoptosis was induced by ER stress. Taken together, our results indicate that knockdown of ERp44 leads to cell apoptosis through the activation of ER stress. (C) 2015 Elsevier Inc. All rights reserved.

submitted time 2016-05-11 Hits1801Downloads998 Comment 0

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