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Light induces petal color change in Quisqualis indica(Combretaceae)

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Plant Diversity 2018年第1期40卷 28-34页

作者： juan yan Menglin Wang Ling Zhang Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China

Petal color change, a common phenomenon in angiosperms, is induced by various environmental and endogenous factors. Interestingly, this phenomenon is important for attracting pollinators and further reproductive success. Quisqualis indica L.(Combretaceae) is a tropical Asian climber that undergoes sequential petal color change from white to pink to red. This color changing process is thought to be a good strategy to attract more pollinators. However, the underlying physiological and biochemical mechanisms driving this petal color change phenomenon is still underexplored. In this context, we investigated whether changes in pH, pollination, light, temperature or ethylene mediate petal color change. We found that the detected changes in petal pH were not significant enough to induce color alterations. Additionally, pollination and temperatures of 20-30℃did not alter the rate of petal color change; however, flowers did not open when exposed to constant temperatures at 15℃ or 35℃.Moreover, the application of ethylene inhibitor, i.e., silver thiosulphate, did not prevent color change. It is worth mentioning here that in our study we found light as a strong factor influencing the whole process of petal color change, as petals remained white under dark conditions. Altogether, the present study suggests that petal color change in Q. indica is induced by light and not by changes in petal pH, pollination, ethylene, or temperature, while extremely low or high temperatures affect flower anthesis. In summary, our findings represent the probable mechanism underlying the phenomenon of petal color change, which is important for understanding flower color evolution.

关键词： Environmental factors Ethylene Petal color pH Pollination Temperature

Some results on entropy dimension for non-autonomous systems

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Applied Mathematics(A Journal of Chinese Universities) 2020年第3期35卷 281-292页

作者： yanG yan-juan WANG Lin WANG Wei School of Mathematics and Statistics Shandong Normal UniversityJi’nan 250014China College of Applied Mathematics Shanxi University of Finance and EconomicsTaiyuan 030006China College of Mathematics and Information Science Hebei Normal UniversityShijiazhuang 050024China

In this paper,the preimage branch t-entropy and entropy dimension for nonautonomous systems are studied and some systems with preimage branch t-entropy zero are ***,formulas calculating the s-topological entropy of a sequence of equi-continuous monotone maps on the unit circle are ***,examples to show that the entropy dimension of non-autonomous systems can be attained by any positive number s are constructed.

关键词： entropy dimension homemorphism finite graphs non-autonomous systems

Research on influence of typical microstructure characteristics of Ni base single crystal on creep rupture and deformation analysis of turbo blade

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航空动力学报 2011年第5期26卷 1148-1158页

作者： CAO juan WANG yan-rong SHI Duo-qi School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

Considering the influence of typical microstructure characteristics on creep performance,a series of UM-F single crystal alloys which had similar element components but different microstructures were used to analyze the relationship between creep life and microstructure characteristics of Ni base single *** main factors were proposed:misfit,volume fraction of precipitate and maximum matrix channel *** Microstate parameter Ymicro was established to estimate the deformation state of the *** linear relationship between the initial value of microstate parameter Y0 and creep life under a certain temperature/load was *** analyzing the high temperature region of turbo blade using the material parameters of DD 3,the creep deformation and the life prediction of the critical points of blade were obtained and the result closed to the test.

关键词：《航空动力学报》期刊摘要编辑部

SP3-Hybridization Feature of Ag4 Superatom in Superatomic Molecules

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： Li-juan yan Long-jiu Cheng Jin-long yang Hefei National Laboratory of Physical Science at the Microscale University of Science and Technology of China Hefei 230026 China Department of Chemistry Anhui University Hefei 230601 China Hefei National Laboratory of Physical Science at the Microscale University of Science and Technology of China Hefei 230026 ChinaSynergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China

Analogous to atoms, superatoms can be used as building blocks to compose molecules and materials. To demonstrate this idea, the possibility of using tetrahedral Ag4 cluster to form a series of superatomic molecules Ag4X4 (X=H, Li, Na, K, Cu, Ag, Au and F, Cl, Br) is discussed. Based on the super valence bond model, a tetrahedral Ag4 cluster can be viewed as a 4-electron superatom, which can mimic a sp3 hybridization C atom. By comparison of the representative superatomic molecules Ag4X4 (X=Au, Cl) with the corresponding simple molecules CX4 (X=H, Cl), the similarities in terms of chemical bonding patterns and molecular orbitals (MOs) are conspicuous. Energy calculations predict that the Ag4 superatom can bind with all the involved ligands. Furthermore, the stabilities of superatomic molecules are enhanced by the large gaps of the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO gaps) and high aromaticity. Our studies may find applications in assembling materials with superatoms.

关键词： Superatom Magic numbers Super valence bond Binding energy Aromaticity

A Novel 3D Cd^(Ⅱ)-CP Based on a Bi-functional(N-/O-Sites) Triazole-modified Carboxyl Ligand:Structure,Topology and Photoluminescence

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Chinese Journal of Structural Chemistry 2022年第2期41卷 85-90,I0009页

作者： ZHAO Dan GUO Ting-Ting AN yan-yan yan juan-Zhi Taiyuan University Taiyuan 030032China

With triazole-modified derivative as link,one new framework[Cd_(5)(μ_(5)-HL^(2-))_(2)(μ_(4)-L^(3-))_(2)(H_(2)O)_(10)]·2H_(2)O(1,H_(3)L=2-(1,2,4-triazol-1-yl)benzene-1,3,5-tricarboxylic acid) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction,powder X-ray diffraction and elemental *** 1exhibits a 3D (3,4,6)-connected net cross-linked by binuclear[Cd_(2)(COO)_(5)]^(-)cluster and mononuclear Cd(Ⅱ)geometry via HL^(2-)/L^(3-)*** crystallizes in triclinic system,space group P1 with a=7.7411(11),b=9.8813(15),c=20.177(3)?,α=85.547(4)°,β=80.603(4)°,γ=67.976(3)°,V=1411.3(4)?^(3),Z=1,M_(r)=1876.89g/mol,D_(c)=2.208 mg/m^(3),μ=1.97 mm^(-1),F(000)=918,GOOF=1.03,the final R=0.0869 and w R=0.1950 for3127 observed reflections with I>2σ(I).The solid photoluminescent behaviour of 1 has been further functionally investigated.

关键词： triazole Cd(Ⅱ)complex crystal structure fluorescence property

Aberrant expression of ether à go-go potassium channel in colorectal cancer patients and cell lines

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World Journal of Gastroenterology 2007年第8期13卷 1257-1261页

作者： Xiang-Wu Ding juan-juan yan Ping An Peng Lü He-Sheng Luo Department of Gastroenterology Renmin Hospital of Wuhan University Wuhan 430060 Hubei Province China Department of Gastroenterology Xiangfan Central Hospital Xiangfan 441021 Hubei Province China

AIM: To study the expression of ether à go-go (Eag1) potassium channel in colorectal cancer and the relation- ship between their expression and clinico-pathological features. METHODS: The expression levels of Eag1 protein were determined in 76 cancer tissues with paired non- cancerous matched tissues as well as 9 colorectal adenoma tissues by immunohistochemistry. Eag1 mRNA expression was detected in 13 colorectal cancer tissues with paired non-cancerous matched tissues and 4 colorectal adenoma tissues as well as two colorectal cancer cell lines (LoVo and HT-29) by reverse transcription PCR. RESULTS: The frequency of positive expression of Eag1 protein was 76.3% (58/76) and Eag1 mRNA was 76.9% (10/13) in colorectal cancer tissue. Expression level of Eag1 protein was dependent on the tumor size, lymphatic node metastasis, other organ metastases and Dukes’ stage (P < 0.05), while not dependent on age, sex, site and degree of differentiation. Eag1 protein and mRNA were negative in normal colorectal tissue, and absolutely negative in colorectal adenomas except that one case was positively stained for Eag1 protein. CONCLUSION: Eag1 protein and mRNA are aberrantly expressed in colorectal cancer and occasionally expressed in colorectal adenoma. The high frequency of expression of Eag1 in tumors and the restriction of normal expression to the brain suggest the potential of this protein for diagnostic, prognostic and therapeutic purposes.

关键词： Colorectal cancer Adenoma Ether à go-go gene, Potassium channels

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Biomedical and Environmental Sciences 2013年第6期26卷 492-495页

作者： YIN Jian Hai YUAN Zhong Ying CAI Hui Xia SHEN Yu juan JIANG yan yan ZHANG Jing WANG yan juan CAO Jian Ping National Institute of Parasitic Diseases Chinese Center for Disease Control and Prevention Key Laboratory of Parasite and Vector Biology MOHChina WHO Collaborating Center for Malaria Schistosomiasis and Filariasis Qinghai Institue for Endemic Disease Prevention and Control

Objective Pigs, as hosts of zoonotic Cryptosporidium species/genotypes, are domestic animals with public health significance. The present study was to characterize the infection rate and species/genotype of Cryptosporidium in pre-weaned and post-weaned pigs from Shanghai and Shaoxing, China. Methods A total of 208 fecal samples （42 from pre-weaned piglets, and 166 from post-weaned pigs） were examined by nested PCR of the 185 rRNA gene and analyzed by phylogenetic DNA fragment sequencing of secondary PCR products. Results Infection was detected in 79 samples （19/42 pre-weaned piglets, and 60/166 post-weaned pigs）. C. suis （14/79） and Cryptosporidium pig genotype II （65/79） were identified; piglets were more susceptible to the former （13/14） and post-weaned pigs to the latter （59/65）. Conclusion Infection of Cryptosporidium spp. in pigs was age-specific; piglets were more susceptible to C. suis while pigs were more susceptible to Cryptosporidium pig genotype II. These findings combined with the isolation of the two Cryptosporidium from water suggest that pigs may be a source of zoonotic Cryptosporidium water pollution. Improvements in pig feeding practices, sewage discharge, feces disposal and field worker protection are therefore important to prevent potential public health problems.

关键词： Cryptosporidium suis Cryptosporidium pig genotype II Age-specificity Pigs China

Smart Colorimetric Corn Starch Films Combined with Anthocyanin-Loaded Glutenin-Carboxymethyl Chitosan Nanocomplexes for Freshness Monitoring of Chilled Pork

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Journal of Renewable Materials 2024年第1期12卷 71-87页

作者： juan yan Wenchao Li Xianfang Zhang Shisheng Liu College of Food Science and Engineering Hainan UniversityHaikou570100China Engineering Research Center for Utilization of Tropical Polysaccharide Resources Ministry of EducationHaikou570100China

In this study,intelligent,pH-responsive colorimetric films were prepared by encapsulating anthocyanins in nanocomplexes prepared from glutenin and carboxymethyl *** nanocomplexes were added to a corn starch matrix and used in the freshness monitoring of chilled *** effects of anthocyanin-loaded nanocomplexes on the physical,structural,and functional characteristics of the films were *** addition of anthocyanin-loaded nanocomplexes increased the tensile strength,elongation at break,hydrophobicity,and light transmittance of the films while decreasing their water vapor *** is because new hydrogen bonds are formed between the film components,resulting in a more homogeneous and dense *** colorimetric film has a significant color response to pH *** films were used in experiments on the freshness of chilled pork,in which the pH changes with changing freshness *** results show that the colorimetric film can monitor changes in the freshness of chilled pork in real time,where orange,pink,and green represent the fresh,secondary fresh,and putrefied states of pork,***,the intelligent colorimetric film developed in this study has good application potential in the food industry.

关键词： Carboxymethyl chitosan glutenin nanocomplexes anthocyanins pH indicator film chilled pork

Conjugation of Chitooligosaccharide-5-fluorouracil with Bovine Serum Albumin

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Chinese Chemical Letters 2006年第11期17卷 1495-1498页

作者： Rong Min WANG Jing Feng SONG Yu Feng HE juan juan MAO yan LI Key Laboratory of Polymer Materials of Gansu Province Institute of Polymer Northwest Normal University Lanzhou 730070

The interaction between chitooligosaccharide-5-fluorouracil （COS-5FU） and bovine serum albumin （BSA） was studied by fluorescence spectroscopy. It was found that an energy transfer between COS-5FU and BSA had been occurred. The binding constants were calculated, k298K=1.175×10^4 L·mol^-1. Based on the mechanism of energy transfer of dipole-dipole interaction between the donor and acceptor, the distance between BSA and COS-SFU was determined.

关键词： Chitooligosaccharide-5-fluorouracil BSA fluorescence spectroscopy.