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1. chinaXiv:202110.00020 [pdf]

Response of C:N:P in the plant-soil system and stoichiometric homeostasis of Nitraria tangutorum leaves in the oasis-desert ecotone, Northwest China

WEI Yajuan; DANG Xiaohong; WANG Ji; GAO Junliang; GAO Yan
Subjects: Geosciences >> Geography

Nitraria tangutorum nebkhas are widely distributed in the arid and semi-arid desert areas of China. The formation and development of N. tangutorum nebkhas are the result of the interaction between vegetation and the surrounding environment in the process of community succession. Different successional stages of N. tangutorum nebkhas result in differences in the community structure and composition, thereby strongly affecting the distribution of soil nutrients and ecosystem stability. However, the ecological stoichiometry of N. tangutorum nebkhas in different successional stages remains poorly understood. Understanding the stoichiometric homeostasis of N. tangutorum could provide insights into its adaptability to the arid and semi-arid desert environments. Therefore, we analyzed the stoichiometric characteristics of N. tangutorum in four successional stages, i.e., rudimental, developing, stabilizing, and degrading stages using a homeostasis model in an oasis-desert ecotone of Northwest China. The results showed that soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents and their ratios in the 0–100 cm soil depth were significantly lower than the averages at regional and global scales and were weakly influenced by successional stages in the oasis-desert ecotone. TN and TP contents and C:N:P in the soil showed similar trends. Total carbon (TC) and TN contents in leaves were 450.69–481.07 and 19.72–29.35 g/kg, respectively, indicating that leaves of N. tangutorum shrubs had a high storage capacity for C and N. Leaf TC and TN contents and N:P ratio increased from the rudimental stage to the stabilizing stage and then decreased in the degrading stage, while the reverse trend was found for leaf C:N. Leaf TP content decreased from the rudimental stage to the degrading stage and changed significantly in late successional stages. N:P ratio was above the theoretical limit of 14, indicating that the growth of N. tangutorum shrubs was limited by P during successional stages. Leaf N, P, and N:P homeostasis in four successional stages was identified as ''strictly homeostasis''. Redundancy analysis (RDA) revealed that soil acidity (pH) and the maximum water holding capacity were the main factors affecting C:N:P stoichiometric characteristics in N. tangutorum leaves. Our study demonstrated that N. tangutorum with a high degree of stoichiometric homeostasis could better cope with the arid desert environment.

submitted time 2021-10-11 From cooperative journals:《Journal of Arid Land》 Hits5599Downloads253 Comment 0

2. chinaXiv:201711.00134 [pdf]

Two New Silver Coordination Polymers Constructed from 3,3-Azodibenzoic Acid and Different Pyridine Derivatives: Syntheses, Structures and Fluorescent Properties

HOU Xiang-Yang; WANG Xiao; REN Yi-Xia; TANG Long; JU Ping; WANG Ji-Jiang; KANG Wei-Wei; LIU Xiao-Li
Subjects: Chemistry >> Physical Chemistry

Two coordination polymers (CPs), {[Ag(ADA)0.5(DPE)]·H2O}n (1) and {[Ag(ADA)0.5(Bipy)0.5]·H2O}n (2), (H2ADA = 3,3-azodibenzoic acid, DPE = 1,2-di(4-pyridyl)- ethylene, Bipy = 4,4?-bipyridine), have been synthesized via solvothermal reactions of Ag+ with ADA2- and/or DPE, Bipy. CPs 1 and 2 were characterized by elemental analyses, IR spectra, thermal behaviors, and X-ray single-crystal diffraction. CPs 1 and 2 feature “Ag···Ag” subunits. CP 1 shows a 3D construction, in which the “Ag···Ag” subunits extend through ADA2- and DPE ligands using μ6-kO,O;kO;kO;kO,O;kO;kO and μ2-kO;kO coordination modes, respectively. It crystallizes in triclinic system, space group P, with a = 0.3808(18), b = 1.2476(6), c = 1.309(6) nm, α = 76.757(5), β = 84.649(5), γ = 86.809(5)?, V = 0.6024(5) nm3, Z = 2, Mr = 351.11, C13H11AgN2O3, Dc = 1.936 g/cm3, F(000) = 348, S = 1.064, R = 0.0323 and wR = 0.0689. CP 2 exhibits a 3D supramolecular structure, in which the “Ag···Ag” subunits are connected by ADA2- and DPE ligands with μ6-kO;kO;kO,O;kO;kO and μ2-kO;kO coordination modes, respectively. Ultimately, through hydrogen bond and π···π interaction, the “Ag···Ag” subunits stabilize the 3D supramolecular structure of 2. It crystallizes in monoclinic, space group C2/c, with a = 25.301(15), b = 13.197(8), c = 6.970(4) nm, β = 102.597(7)?, V = 2.271(2) nm3, Z = 8, C12H10AgN2O2.50, Mr = 330.09, Dc = 1.931 g/cm3, F(000) = 1304, S = 1.082, R = 0.1107 and wR = 0.2984. The fluorescence properties of CPs 1 and 2 have been also investigated.

submitted time 2017-11-05 From cooperative journals:《结构化学》 Hits2575Downloads1043 Comment 0

3. chinaXiv:201711.00151 [pdf]

Crystal Structures, Characterizations and Fluorescence Properties of Two 3D Ca(II)/Sr(II) Coordination Polymers Based on 2-Sulfoterephthalate

WANG Zhi-Xiang; CAO Jia; Ren Yi-XiaZHOU Shan-Hong; ZHANG Mei-Li; WANG Ji-Jiang
Subjects: Chemistry >> Physical Chemistry

Two alkaline earth metal coordination polymers [M(2-Hstp)(H2O)] (M = Ca2+ (1) and Sr2+ (2), 2-H3stp = 2-sulfoterephthalate) were synthesized under hydrothermal conditions by the precursor [Mn(2-Hstp)2(4,4?-Hbpy)2] and alkaline earth metal salts. The two alkaline earth complexes are not isomorphic. Complex 1 crystallizes in the monoclinic space group P21/m, while 2 in the monoclinic space group P21/c, despite of their similar formulas. In 1, the Ca2+ ion lies in a seven-coordinated pentagon bipyramidal configuration, coordinated with five 2-Hstp2- anions and one water molecule. However, the Sr2+ ion in 2 is coordinated by nine oxygen atoms to form a single-capped square antiprism polyhedron. Both 1 and 2 exhibit π-π* emission of the 2-sulfoterephthalate ligand.

submitted time 2017-11-05 From cooperative journals:《结构化学》 Hits1271Downloads760 Comment 0

4. chinaXiv:201711.00168 [pdf]

Syntheses, Crystal Structures, and Photoluminescent Properties for One New Cd(II) CP Based on 3,5-Bis(4?-carboxy-phenyl)-1,2,4-triazole and 1,4-Bis(imidazol-1-ylmethyl)benzene

HOU Xiang-Yang; WANG Xiao; REN Yi-Xia; WANG Ji-Jiang; JIN Wei; KANG Wei-Wei; MA Xin; HAN Xing-Xing
Subjects: Chemistry >> Physical Chemistry

One new coordination polymer (CP) [Cd(bct)(bib)]·2(H2O) (1), based on 3,5-bis(4?-carboxy- phenyl)-1,2,4-triazole (H2bct) and 1,4-bis(imidazol-1-ylmethyl)benzene(bib), has been synthesized by hydrothermal method, and its structure was determined and characterized by single-crystal X-ray diffraction analysis, elemental analysis, IR spectroscopy, and thermogravimetric analysis. The crystal structure of CP 1 is a three-dimensional framework with (3,5)-connected topology, where the bct ligands adopt a ?3-kO,kO,kO coordination mode connecting with three Cd centers and the bib ligands adopt a ?2-kN,kN coordination mode bridging two Cd ions. It crystallizes in monoclinic system, space group C2/c, with a = 2.6838(4), b = 1.24221(17), c = 1.8011(2) nm, β = 102.939(2)?, V = 5.8522(13) nm3, Z = 8, C30H27CdN7O6, Mr = 694.00, Dc = 1.566 g/cm3, F(000) = 2784, S = 1.055, R = 0.0294 and wR = 0.0731. Furthermore, solid-state photoluminescence measurements show that CP 1 produces strong emissions at room temperature.

submitted time 2017-11-05 From cooperative journals:《结构化学》 Hits1386Downloads761 Comment 0

5. chinaXiv:201605.00732 [pdf]

PS341 inhibits hepatocellular and colorectal cancer cells through the FOXO3/CTNNB1 signaling pathway

Yang, Zhao; Zhou, Xiumin; Tao, Min; Li, Chong; Zhu, Hong; Yang, Zhao; Liu, Shengwu; Liu, Shengwu; Zhu, Mingao; Zhang, Hong; Wang, Ji; Xu, Qian; Lin, Kaisu; Li, Chong; Yang, Zhao;
Subjects: Biology >> Biophysics

Hepatocellular carcinoma (HCC) and colorectal cancer (CRC) are among the most common cancers across the world. Particularly, a large number of patients with CRC also have liver metastasis. Currently, there are just a few targeted drugs against these two kinds of tumors which can only benefit a very small population of patients. Therefore, the need of more effective therapeutic drugs or strategies for these two types of cancers is urgent. PS341 (Bortezomib) is the first proteasome inhibitor drug which has been approved in clinical treatment for multiple myeloma. Here we demonstrated that PS341 negatively regulated HCC and CRC both in vitro and in vivo, including the inhibition of cell proliferation, epithelial-mesenchymal transition (EMT), the expression of stemness-related genes, cell migration and invasiveness. Mechanically, PS341 upregulated the expression of FOXO3, which inhibited the transcriptional activation of CTNNB1. The downregualtion of CTNNB1 led to apoptosis, cell cycle arrest, and the inhibition of migration, invasion, self-renewal and tumor formation of these two cancer types. In sum, our findings shed light on the PS341 mediated targeted therapy against both HCC and CRC in the future.

submitted time 2016-05-05 Hits1491Downloads906 Comment 0

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