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1

Phylogenetic discontinuity of Plateau zokor (Myospalax baileyi Thomas) populations in Qinghai-Tibetan Plateau

100%

Tang L. , Zhang T. , Lin G. , Su J.

Polish Journal of Ecology

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2010

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tom 58

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nr 1

EN

Mitochondrial cytochrome b gene sequences and morphological data (body length, hind foot length, etc.) for twelve populations with pairwise distances 27–600 km in Qinghai-Tibetan Plateau (distributed in Qinghai, Gansu and Sichuan Province, and at the altitude 3020–4550 m) in Western China were used to investigate the phylogeographical pattern of Plateau zokor (Myospalax baileyi Thomas). There was a little disparity between mtDNA genetic distance and morphological Euclidean distance on population relationships. However, there is a significant correlation (P <0.001) calculated by Mantel’s tests was validated between mtDNA and morphology distances. Analysis of Molecular Variance showed that most of the observed genetic variations occurred between populations, indicating little maternal gene flow between them, as a result of geographical restrictions. Phylogenetic analysis coupled with cluster analysis together showed that the substantial population structuring and phylogenetic discontinuities existed within this species. The evident allopatric population structuring of this subterranean rodent may mostly result from its specialized subterranean excavating behavior with high energy costs, predation from grassland raptors and also the influences of perennial tundra and environmental desiccation in the Qinghai-Tibetan Plateau.

2

Experience-dependent acquisition of visuomotor behavioral representation in primary visual cortex

100%

Puscian A. , Benisty H. , Tang L. , Higley M. J.

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2019

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tom 79

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nr Suppl.1

EN

INTRODUCTION: The role of primary sensory cortical areas in perception and behavior remains unclear. Moreover, the functional plasticity of these circuits during task acquisition is largely unknown. AIM(S): Here, we developed a visual learning task in awake, head-fixed mice in which animals learn to associate a small drifting grating stimulus with an aversive air puff to the cornea, driving the establishment of a conditioned blink response. METHOD(S): We previously showed that both task acquisition and performance require intact primary visual cortex (V1). Pairing this approach with 2‑photon calcium imaging of identified neuronal subpopulations in V1, we monitored cellular activity across two weeks of learning. RESULTS: Our results show that the population activity of excitatory neurons in both layer 2/3 and 5 reliably encodes the presence of a sensory stimulus throughout training, but acquires the ability to accurately represent motor output over several days. Analysis of individual neurons demonstrates that cells not encoding behavior significantly lose their visual responses during learning, producing an overall enhancement of the population-level representation. We find similar results for GABAergic interneurons expressing parvalbumin and vasoactive intestinal peptide. However, somatostatin‑expressing interneurons fail to encode behavior at any point in training, suggesting that cell type‑specific mechanisms promote plasticity in V1 circuits associated with learning. CONCLUSIONS: In conclusion, our data suggest that visual experience produces a functional reorganization of both excitatory and inhibitory networks that facilitates efficient performance in visuomotor behavior.

3

Phylogenetic discontinuity of plateau zokor (myospalax baileyi thomas) populations in qinghai-tibetan plateau

100%

Tang L. , Zhang T. , Lin G. , Su J.

Polish Journal of Ecology

|

2010

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tom Vol. 58, nr 1

167-176

EN

Mitochondrial cytochrome b gene sequences and morphological data (body length, hind foot length, etc.) for twelve populations with pairwise distances 27-600 km in Qinghai-Tibetan Plateau (distributed in Qinghai, Gansu and Sichuan Province, and at the altitude 3020-4550 m) in Western China were used to investigate the phylogeographical pattern of Plateau zokor (Myospalax baileyi Thomas). There was a little disparity between mtDNA genetic distance and morphological Euclidean distance on population relationships. However, there is a significant correlation (P <0.001) calculated by Mantel's tests was validated between mtDNA and morphology distances. Analysis of Molecular Variance showed that most of the observed genetic variations occurred between populations, indicating little maternal gene flow between them, as a result of geographical restrictions. Phylogenetic analysis coupled with cluster analysis together showed that the substantial population structuring and phylogenetic discontinuities existed within this species. The evident allopatric population structuring of this subterranean rodent may mostly result from its specialized subterranean excavating behavior with high energy costs, predation from grassland raptors and also the influences of perennial tundra and environmental desiccation in the Qinghai-Tibetan Plateau.

4

Impact of the Mixture of Hexa(N-hydroxymethyl)amidocyclotriphosphazene and Partially Methylated Melamine Formaldehyde Resin on the Flame Retardancy of Paper

88%

Tang L. , Zhao J. , Sui X. , Song H. , He W.

Fibres & Textiles in Eastern Europe

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2016

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tom Vol. 24, no. 4 (118)

153--160

EN

The flame retardancy of the mixture of hexa(N-hydroxymethyl)amidocyclotriphosphazene and partially methylated melamine formaldehyde resin (HHMATP/PMMM) in paper was proposed by limiting oxygen index measurement (LOI), the vertical burning test and cone calorimetry test (CCT). In our research, the LOI of washed FR-paper could still be up to 33.5%; the after flame time , and burning time were reduced to 4.8 s & 0 s, and the char length was only 12.0 mm. While the results of CCT imply that compared with non-flame retarded paper, the heat release rate (HRR) of FR-paper with HHMAPT/PMMM increases gently; the mass loss becomes significantly slow, and the prolonged maximum heat release rate (PHRR), average heat release rate (MHRR), average effective heat of combustion (MEHC) and total heat release (THR) drop greatly. According to the experimental results, HHMATP/PMMM has not only excellent flame retardancy in paper but also good water resistance, with HHMATP/PMMM playing a flame retardant role mainly by means of the condensed phase mechanism.

PL

Badano zmniejszenie palności papieru stosując mieszaninę hexa(N-hydroxymethyl)amidocyclotriphosphazene i częściowo zmetylowanej żywicy melamine formaldehyde (HHMATP/PMMM) poprzez indeks tlenowy (LOI), test pionowego palenia i test kalorymetru stożkowego (CCT). Eksperymenty wykazały, że HHMATP/PMMM ma nie tylko dobry wpływ na ograniczenie palności papieru, ale również na jego odporność na działanie wody.

5

Knitted silk mesh-like scaffold incorporated with sponge-like regenerated silk fibroin/collagen I and seeded with mesenchymal stem cells for repairing Achilles tendon in rabbits

75%

Tang L. , Yang Y. , Li Y. , Yang G. , Luo T. , Xue Y. , Zhang W.

Acta of Bioengineering and Biomechanics

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2018

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tom Vol. 20, no. 3

77--87

EN

A scaffold knit with natural sericin-free silk fibroin fiber possesses desirable mechanical properties, biocompatibility, ease of fabrication, and slow degradability. However, regenerated silk fibroin degrades faster than natural silk. In this study, natural silk fibroin fiber mesh-like scaffolds were prepared by a weft-knitting method and the pores were filled with sponge-like regenerated silk fibroin-collagen I. The microporous sponge and mesh-like scaffolds were fused to achieve gradient degradation of the scaffolds, and rabbit bone marrow mesenchymal stem cells (BMSCs) were seeded onto the scaffolds to form scaffold–BMSCs composites. The composites were implanted into gap defects made in the rabbit Achilles tendon. Twenty weeks after implantation, histological observation showed that tendon-like tissue had formed, collagen I mRNA was expressed, abundant collagen was generated, and that there was no obvious degradation of silk. The maximum load of the neo-Achilles tendon was 62.14% that of the natural Achilles tendon. These outcomes were superior to those obtained in the group implanted with a scaffold without BMSCs. These findings suggest the feasibility of constructing tissue-engineered tendons using weft-knitted silk scaffolds incorporated with sponge-like regenerated silk fibroin/collagen I and seeded with BMSCs, and show potential of the scaffold–BMSCs composites to repair Achilles tendon defects.

6

Impact of Hexaamidocyclotriphosphazene on the Flame Retardancy of Paper

75%

Tang L. , Bi W. , Ke Y. , Song H. , He W. , Liu Y.

Fibres & Textiles in Eastern Europe

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2016

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tom Vol. 24, no. 4 (118)

148--152

EN

In this paper, the flame retardancy of hexaamidocyclotriphosphazene (HACTP) in paper was studied by limiting oxygen index measurement, the vertical burning test and cone calorimetry test. Meanwhile the mechanism was discussed by the analysis of residues obtained in the cone calorimeter test. The experimental results revealed that HACTP had excellent flame retardancy in paper.

PL

Badano zmniejszenie palności papieru stosując hexaamidocyklotrifosfazen (HACTP) poprzez indeks tlenowy, test pionowego palenia, i test kalorymetru stożkowego. Badano również mechanizm ograniczenia palności poprzez analizę resztek uzyskanych z testu kalorymetru stożkowego. Eksperymenty wykazały, że HACTP ma wybitny wpływ na zmniejszenie palności papieru.

7

Syntheses, Properties and Crystal Structures of One-dimensional Transition Metal-Azide Coordination Polymers via Hydrogen Bonds

75%

Li Q. , Zhang L. , Peng F. , Ge Y. , Chen L. , Tang L.

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2005

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tom Vol. 79 / nr 8

1389-1397

EN

Three novel mononuclear transition metal-azide compounds, Mn(PzBu-t)4(N3)2 (1), Co(PzBu-t)4(N3)2 (2) and Co(PzBu-t)3(N3)3 (3) (PzBu-t = 3-tert-butyl pyrazole), have been synthesized and characterized by elemental analysis, IR and UV-Vis spectra, and the crystal structures of compounds 1 and 3 have been determined. Crystal data for 1: triclinic, space group P1 with a = 8.0844(9), b = 10.1230(12), c = 12.1046(13) A, alfa = 91.854(3)°, beta = 108.495(2)°, gamma =101.598(2)°, V = 915.33(18) A3 and Z = 1. Crystal data for 3: monoclinic, space group P2(1) with a = 10.3286(9), b = 23.593(2), c = 12.7735(10) A,beta = 106.659(2)°, V = 2982.0(4) A3 and Z= 2. The azide ions in compound 1 are coordinated to manganese(II) ions in trans centrosymmetric octahedral configuration. However, compound 3 shows two unsymmetrical molecules with distorted octahedral geometry ligated by three azide anions and three 3-tert-butyl pyrazole ligands in crystal cell. The compounds are aggregated to form one-dimensional chain through (pyrazole)N-H...N(azide) hydrogen bonds, respectively. In aqueous solution, the reaction of compound 2 with azide excess (2 equivalents) and H2O2 was investigated, and the product was isolated and identified to be homogeneous as compound 3. The result suggests that the compound 3, as the oxidation product of compound 2, was formed by the change of the coordination geometry around cobalt ion in the reaction process, due to the binding of peroxides to the cobalt ion via the removal of the pyrazole ligand.

8

Influence of heat stress on leaf morphology and nitrogen–carbohydrate metabolisms in two wucai (Brassica campestris L.) genotypes

63%

Yuan L. , Tang L. , Zhu S. , Hou J. , Chen G. , Liu F. , Liu S. , Wang C.

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2017

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tom 86

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nr 2

EN

Heat stress is a major environmental stress that limits plant growth and yield worldwide. The present study was carried out to explore the physiological mechanism of heat tolerant to provide the theoretical basis for heat-tolerant breeding. The changes of leaf morphology, anatomy, nitrogen assimilation, and carbohydrate metabolism in two wucai genotypes (WS-1, heat tolerant; WS-6, heat sensitive) grown under heat stress (40°C/30°C) for 7 days were investigated. Our results showed that heat stress hampered the plant growth and biomass accumulation in certain extent in WS-1 and WS-6. However, the inhibition extent of WS-1 was significantly smaller than WS-6. Thickness of leaf lamina, upper epidermis, and palisade mesophyll were increased by heat in WS-1, which might be contributed to the higher assimilation of photosynthates. During nitrogen assimilation, WS-1 possessed the higher nitrogen-related metabolic enzyme activities, including nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT), and glutamate dehydrogenase (GDH), which were reflected by higher photosynthetic nitrogen-use efficiency (PNUE) with respect to WS-6. The total amino acids level had no influence in WS-1, whereas it was reduced in WS-6 by heat. And the proline contents of both wucai genotypes were all increased to respond the heat stress. Additionally, among all treatments, the total soluble sugar content of WS-1 by heat got the highest level, including higher contents of sucrose, fructose, and starch than those of WS-6. Moreover, the metabolism efficiency of sucrose to starch in WS-1 was greater than WS-6 under heat stress, proved by higher activities of sucrose phosphate synthase (SPS), sucrose synthase (SuSy), acid invertase (AI), and amylase. These results demonstrated that leaf anatomical alterations resulted in higher nitrogen and carbon assimilation in heat-tolerant genotype WS-1, which exhibited a greater performance to resist heat stress.

9

Expression of factors involved in the regulation of angiogenesis in the full-term human placenta: effects of in vitro fertilization

63%

Li C. , Zhang Y. , Tang L. , Zhao H. , Gao C. , Gao L. , Cui Y. , Liu J.

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nr 2

10

Molecular cloning and characterization of a jasmonate biosynthetic pathway gene for allene oxide cyclase from Jatropha curcas

63%

Liu B. , Wang W. , Gao J. , Chen F. , Wang S. , Xu Y. , Tang L. , Jia Y.

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nr 3

EN

Herein, we cloned a full-length cDNA encoding allene oxide cyclase (AOC, EC 5.3.99.6) that is a key enzyme in jasmonates (JAs) biosynthetic pathway from Jatropha curcas L., an important plant species as its seed is the raw material for biodiesels, named as JcAOC (GenBank accession no. FJ874630). The cDNA was 924 bp in length with a complete open reading frame of 750 bp, which encoded a polypeptide of 250 amino acids including a putative signal peptide of 65 amino acid residues and a mature protein of 185 amino acids with a predicted molecular mass of 20.7 kDa and a isoelectric point of 6.24. Phylogenetic analysis indicated that JcAOC belonged to the AOC superfamily. Semi-quantitative RT-PCR analysis revealed that JcAOC mRNA was expressed in roots, stems, leaves, young seeds, endosperms, and flowers, but that the expression level was highest in leaves and lowest in seeds, and mRNA expression of JcAOC could be induced by salt stress (300 mM NaCl) and low temperature (4℃). Furthermore, the full-length coding region of JcAOC excluding signal peptide sequence was inserted into pET-30a and was successfully expressed in Escherichia coli. Overexpression of JcAOC in E. coli conferred its resistance to salt stress and low temperature.

11

Analysis of miRNA-seq combined with gene expression profile reveals the complexity of salinity stress response in Oryza sativa

63%

Wang Q. , Geng T. , Zhu S. , Li R. , Tong Y. , Wang S. , Chen F. , Tang L. , He Y.

Acta Physiologiae Plantarum

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2017

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tom 39

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nr 12

12

Analysis of chloramphenicol in drinking water using an evaporation preparative step and isotope dilution liquid chromatography–tandem mass spectrometry

63%

Li Y. , Liu X. , Zhang R. , ZomPa D. , Luo P. , Tang L. , Liu X. , Zhou Y. , Wen S.

Acta Chromatographica

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2018

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tom Vol. 30, no. 1

17--20

EN

A reliable isotope dilution method for the determination of chloramphenicol (CAP) in drinking water was developed by using an evaporation preparative step. Each sample was monitored by ultrahigh-pressure liquid chromatography (UHPLC) coupled to tandem mass spectrometry (MS/MS) using an electrospray ionization interface (ESI) in negative ion modes. Recoveries of spiked samples were in the range from 93.2% to 95.7% with intra-day relative standard deviation lower than 6.7% and inter-day relative standard deviation lower than 8.2%. Limit of quantification (LOD) was 0.002 ng/mL. The developed method was successfully applied to the analysis of CAP in drinking water of Shannan region of Tibet.