Effect of Li on the microstructure and electrical properties of (K_0.17Na_0.83)NbO_3 lead-free piezoceramics

Guo-Zhong Zang,Yan Wang,Xiu-Jie Yi,Juan Du,Zhi-Jun Xu 한국물리학회 2011 Current Applied Physics Vol.11 No.2

Lead-free (K_0.17Na_(0.83-x)Li_x)NbO_3 piezoceramics were synthesized by conventional solid state sintering and the effect of Li on the microstructure and electrical properties was investigated. The experimental results show that 4 mol% Li doping facilitates the grain growth and increases the density of the ceramics. The measurement of dielectric properties reveals that the orthorhombic-tetragonal (T_(O-T)) and tetragonalcubic (T_C) phase transition temperatures change linearly with increasing Li content and the sample with x = 0.06 exhibits the highest T_C of 429 ℃ and lowest T_(O-T) of 181 ℃. Because of the wide apart of T_(O-T) from room temperature, no polymorphic phase structures were obtained and the piezoelectric strain coeffi-cient d_33 and piezoelectric coupling constant k_p varied between low values of 57, 61 pC/N and 0.18, 0.24,respectively with less than 6 mol% Li doping.

Characteristics and Risk Factors of Functional Dyspepsia Fulfilling the Rome IV Criteria Overlapping With Gastroesophageal Reflux Disease, Irritable Bowel Syndrome, and Functional Constipation in South China

( Yan-qin Long ),( Wen-li Xu ),( Lu-xiu Li ),( Hui-qin He ),( Jing-jie Wang ),( Guo-dong Shan ),( Ning Dai ),( Hong-tan Chen ) 대한소화기기능성질환·운동학회 2024 Journal of Neurogastroenterology and Motility (JNM Vol.30 No.2

Background/Aims Functional dyspepsia (FD) overlapping with other gastrointestinal disorders are quite common. The characteristics of FD overlap in Chinese population with latest Rome IV criteria were unclear. This large-scale outpatient-based study assessed the characteristics of FD overlap in South China. Methods Consecutive FD patients visited the Gastroenterology Clinic at 2 tertiary medical centers in Hangzhou, China who fulfilled the Rome IV criteria were enrolled. Complete questionnaires related to the gastrointestinal symptoms (Rome IV criteria), Reflux Disease Questionnaire, anxiety and depression, quality of sleep and life, and demographic information were collected. Results Among the total of 3281 FD patients, 50.69% overlapped with gastroesophageal reflux disease, 21.46% overlapped with irritable bowel syndrome, 6.03% overlapped with functional constipation. FD overlap had higher proportion of single/divorced/widowed rate, high education level, being employed, drinking, night shift, unhealthy dietary habit than FD only (P < 0.05). They had higher frequency of consultation and economic burden, as well as lower scores in quality of life (P < 0.001). Multivariate logistic regression showed that increasing age, female, low body mass index, history of gastroenteritis, anxiety, depression, and poor sleep quality were independent risk factors for FD overlap. Conclusions FD overlap was quite common in China with high economic burden and poor quality of life, FD patients with history of gastroenteritis, anxiety, depression, and poor sleep quality were more likely to have overlap disorders. Awareness of the physical and psychosocial stressors in overlapping condition would help optimize the management of FD overlap in clinical practice. (J Neurogastroenterol Motil 2024;30:184-193)

A Novel 3D Polypseudo-rotaxane Metal-organic Framework Based on a Flexible Bis-pyridyl-bis-amide Ligand

Xiu-Li Wang,Na Han, Hong-Yan Lin,Chuang Xu,Jian Luan,Guo-Cheng Liu 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.11

A novel 3D compound {[Cu(L)(H2O)4][Cu2(SIP)2(L)2]}·2H2O (1) (L = N,N-bis(4-pyridinecarboxamide)-1,4- butane, SIP = 5-sulfoisophthalate) is hydrothermally synthesized. X-ray diffraction analysis reveals that compound 1 is composed of 2D anionic [Cu2(SIP)2(L)2]n 2n− double-layers and discrete 1D cationic [CuL(H2O)4]n 2n+ polymeric chains, which represents a rare 3D polypseudo-rotaxane MOF from intercalation of 1D and 2D framework. In addition, the luminescent property and electrochemical behavior of compound 1 have been investigated.

Multiplex Real-time PCR for RRM1, XRCC1, TUBB3 and TS mRNA for Prediction of Response of Non-small Cell Lung Cancer to Chemoradiotherapy

Wu, Guo-Qiu,Liu, Nan-Nan,Xue, Xiu-Lei,Cai, Li-Ting,Zhang, Chen,Qu, Qing-Rong,Yan, Xue-Jiao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.10

Background: This study was aimed to establish a novel method to simultaneously detect expression of four genes, ribonucleotide reductase subunit M1(RRM1), X-ray repair cross-complementing gene 1 (XRCC1), thymidylate synthase (TS) and class III ${\beta}$-tubulin (TUBB3), and to assess their application in the clinic for prediction of response of non-small cell lung cancer (NSCLC) to chemoradiotherapy. Materials and Methods: We have designed four gene molecular beacon (MB) probes for multiplex quantitative real-time polymerase chain reactions to examine RRM1, XRCC1, TUBB3 and TS mRNA expression in paraffin-embedded specimens from 50 patients with advanced or metastatic carcinomas. Twenty one NSCLC patients receiving cisplatin-based first-line treatment were analyzed. Results: These molecular beacon probes could specially bind to their target genes in homogeneous solutions. Patients with low RRM1 and XRCC1 mRNA levels were found to have apparently higher response rates to chemoradiotherapy compared with those with high levels of RRM1 and XRCC1 expression (p<0.05). The TS gene expression level was not significantly associated with chemotherapy response (p>0.05). Conclusions: A method of simultaneously detecting four molecular markers was successfully established and applied for evaluation of chemoradiotherapy response. It may be a useful tool in personalized cancer therapy.

A Novel 3D Polypseudo-rotaxane Metal-organic Framework Based on a Flexible Bis-pyridyl-bis-amide Ligand

Wang, Xiu-Li,Han, Na,Lin, Hong-Yan,Xu, Chuang,Luan, Jian,Liu, Guo-Cheng Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.11

A novel 3D compound $\{[Cu(L)(H_2O)_4][Cu_2(SIP)_2(L)_2]\}{\cdot}2H_2O$ (1) (L = N,N-bis(4-pyridinecarboxamide)-1,4-butane, SIP = 5-sulfoisophthalate) is hydrothermally synthesized. X-ray diffraction analysis reveals that compound 1 is composed of 2D anionic $[Cu_2(SIP)_2(L)_2]_n{^{2n-}}$ double-layers and discrete 1D cationic $[CuL(H_2O)_4]_n{^{2n+}}$ polymeric chains, which represents a rare 3D polypseudo-rotaxane MOF from intercalation of 1D and 2D framework. In addition, the luminescent property and electrochemical behavior of compound 1 have been investigated.

Cloning and expression of a Chk1 gene in Daphnia pulex during different modes of reproduction

Xiaoge Guo,Shanliang Xu,Xuemei Yan,Wei Zhou,Xinyu Dai,Xiu Zou,Chunlin Wang,Danli Wang,Yunlong Zhao 한국유전학회 2015 Genes & Genomics Vol.37 No.9

The full-length cDNA of a Chk1 gene (DpChk1) was cloned from Daphnia pulex using RACE method. This cDNA is 1767 bp in length, consisting of a 1497 bp open reading frame encoding 498 amino acid protein. The deduced DpChk1 protein sequence contains phosphorylation sites, three conserved Ser-Gln and Thr- Gln motifs and shares 51–55 % similarity with A. pisum, M. rotundata, D. melanogaster, A. echinatior, B. terrestris, R. pulchellus and M. occidentalis, respectively. Gene expression analysis showed that Chk1 is differentially expressed in D. pulex during different reproductive modes. DpChk1 expression in sexually-reproducing females and males is significantly higher than in parthenogenetic Daphnia. Whole-mount in situ hybridization revealed that DpChk1 was expressed during two kinds of reproductive modes. In parthenogenetic females, hybridization signals were found in the antennae and thoracic limb, whereas expression levels in the corresponding sites of sexuallyreproducing females were relatively strong, DpChk1 could not be detected in the gonads of ephippial and parthenogenetic females. Taken together, these different reproductive stages and sex specific expression patterns are regulated temporally and spatially. We speculate that DpChk1 may be involved in conversion between different stages of reproduction and in sexual differentiation in D. pulex.

An integrated study of tyrosinase inhibition by rutin: progress using a computational simulation.

Si, Yue-Xiu,Yin, Shang-Jun,Oh, Sangho,Wang, Zhi-Jiang,Ye, Sen,Yan, Li,Yang, Jun-Mo,Park, Yong-Doo,Lee, Jinhyuk,Qian, Guo-Ying Adenine Press 2012 Journal of biomolecular structure & dynamics Vol.29 No.5

<P>Tyrosinase inhibition studies have recently gained the attention of researchers due to their potential application values. We simulated docking (binding energies for AutoDock Vina: -9.1 kcal/mol) and performed a molecular dynamics simulation to verify docking results between tyrosinase and rutin. The docking results suggest that rutin mostly interacts with histidine residues located in the active site. A 10 ns molecular dynamics simulation showed that one copper ion at the tyrosinase active site was responsible for the interaction with rutin. Kinetic analyses showed that rutin-mediated inactivation followed a first-order reaction and mono- and biphasic rate constants occurred with rutin. The inhibition was a typical competitive type with K(i) = 1.100.25 mM. Measurements of intrinsic and ANS-binding fluorescences showed that rutin showed a relatively strong binding affinity for tyrosinase and one possible binding site that could be a copper was detected accompanying with a hydrophobic exposure of tyrosinase. Cell viability testing with rutin in HaCaT keratinocytes showed that no toxic effects were produced. Taken together, rutin has the potential to be a potent anti-pigment agent. The strategy of predicting tyrosinase inhibition based on hydroxyl group number and computational simulation may prove useful for the screening of potential tyrosinase inhibitors.</P>

Electrospun Polyphenylquinoxaline Ultrafine Non-woven Fibrous Membranes with Excellent Thermal and Alkaline Resistance: Preparation and Characterization

Chen-yu Guo,Lu-meng Yin,Jin-gang Liu,Xin-ke Wang,Na Zhang,Lin Qi,Yan Zhang,Xiao Wu,Xiu-min Zhang 한국섬유공학회 2019 Fibers and polymers Vol.20 No.12

A series of polyphenylquinoxaline (PPQ) ultrafine non-woven fibrous membranes have been first successfullyprepared via the electrospinning procedure with the soluble PPQ solutions as the starting materials. For this purpose, variousorgano-soluble PPQ resins were synthesized via the one-step high temperature polycondensation procedure from thearomatic ether-bridged bis(α-diketone) and bis(o-diamine) monomers. Flexible ether linkages and pendant bulky phenylsubstituents endowed the PPQ resins good solubility in polar aprotic solvents. The high-molecular-weight PPQ resins weredissolved in N-methyl-2-pyrrolidone (NMP) to afford the PPQ electrospinning solution except PPQ-Ia derived from 4,4'-oxydibenzil (ODB) and 3,3'-diaminobenzidine (DAB) due to the limited solubility in the solvent. All the derived PPQultrafine non-woven fibrous membranes maintained good structure integrity after hydrolysis aging either at room temperature(25 oC) for 72 h or at refluxing temperature (100 oC) for 24 h in an aqueous sodium hydroxide (NaOH) solution at a solidcontent of 20 wt%. Comparatively, the polyimide (PI) reference electrospun membrane (PI-ref) derived from 1,2,4,5-pyrromellitic anhydride (PMDA) and 4,4'-oxydianiline (ODA) lost its original structure only after boiling in the same NaOHsolution within 3 h. In addition, the developed PPQ ultrafine non-woven fibrous membranes exhibited good thermal stabilitywith the 5 % weight loss temperatures (T5%) higher than 555.0 oC in nitrogen and glass transition temperatures (Tg) in therange of 248.1-266.1 oC, respectively.

Preparation and Characterization of Electrospun Polyimide Microfibrous Mats with High Whiteness and High Thermal Stability from Organo-soluble Polyimides Containing Rigid-rod Moieties

Chen-yu Guo,Jin-gang Liu,Lu-meng Yin,Meng-ge Huangfu,Yan Zhang,Xiao Wu,Xiu-min Zhang 한국섬유공학회 2018 Fibers and polymers Vol.19 No.8

A series of flexible and tough polyimide (PI) microfibrous mats (PI-1~PI-4) have been prepared via the one-step electrospinning procedure with the organo-soluble PI resins as the starting materials. For this purpose, four PI resins were first synthesized by the chemical imidization reaction from 2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and four aromatic diamines containing rigid-rod moieties in their molecular skeletons, respectively. The PI resins derived from 6FDA and aromatic diamines, including PI-1 from 2-(4-aminophenyl)-5-aminobenzimidazole (APBI), PI-2 from 2-(4-aminophenyl)-5-aminobenzoxazole (APBO), PI-3 from 4,4′-diaminobenzanilide (DABA), and PI-4 from 2- chloro-4,4-diaminobenzanilide (Cl-DABA) exhibited good solubility in polar aprotic solvents, such as N-methyl-2- pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc). Flexible and tough microfibrous mats were successfully prepared by a one-step electrospinning procedure from the PI/DMAc solution (solid content: 15-20 wt%; absolute viscosity: 8000- 10000 mPa·s). The derived PI mats exhibited good whiteness according to the CIE Lab measurements with W (whiteness) values as high as 94.31, L (lightness) values higher than 94.00, b* (yellowness) values as low as 2.98 and yellow indices (YI) as low as 4.87. In addition, the prepared PI mats exhibited excellent thermal and dimensional stability with the glass transition temperatures (Tg) higher than 345 oC and linear coefficients of thermal expansion (CTE) as low as 27.8×10-6 /K.

An Overlooked Effect of Glycine Betaine on Fermentation: Prevents Caramelization and Increases the L-Lysine Production

( Jian Zhong Xu ),( Xiu Hua Xia ),( Jun Lan Zhang ),( Yan Feng Guo ),( Wei Guo Zhang ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.10

This article focuses on the effects of glycine betaine on preventing caramelization, and increasing DCW and L-lysine production. The additional glycine betaine not only decreased the browning intensity (decreased 4 times), and the concentrations of 5-hydroxymethylfurfural (decreased 7.8 times) and furfural (decreased 12 times), but also increased the availability of glucose (increased 17.5%) for L-lysine production. The DCW and L-lysine production were increased by adding no more than 20 mM glycine betaine, whereas the DCW and L-lysine production were decreased with the reduction of pH values, although pH had a better response to prevent caramelization than did glycine betaine. For L-lysine production, the highest increase (40%) was observed on the media with 20 mM glycine betaine. The crucial enzymes in glycolysis and L-lysine biosynthesis pathway were investigated. The results indicated that additional glycine betaine increases the activity of enzymes in glycolysis, in contrast to the effect of pH. All the results indicated that glycine betaine can be used to prevent caramelization and increase the L-lysine production. By applying this strategy, glucose would not be have to be separated from the culture media during autoclaving so that factories can save production costs and shorten the fermentation period.