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1Barometric altimetry system as virtual constellation applied in CAPS显示文摘This work describes the barometric altimetry as virtual constellation applied to the Chinese Area Positioning System (CAPS), which uses the transponders of communication satellites to transfer navigation messages to users. Barometric altimetry depends on the relationship of air pressure varying with altitude in the Earth’s atmosphere. Once the air pressure at a location is measured the site altitude can be found. This method is able to enhance and improve the availability of three-dimensional positioning. The difficulty is that the relation between barometric pressure and altitude is variable in different areas and under various weather conditions. Hence, in order to obtain higher accuracy, we need to acquire the real-time air pressure corresponding to an altimetric region’s reference height. On the other hand, the altimetry method will be applied to satellite navigation system, but the greatest difficulty lies in how to get the real-time air pressure value at the reference height in the broad areas overlaid by satellite navigation. We propose an innovational method to solve this problem. It is to collect the real-time air pressures and temperatures of the 1860 known-altitude weather observatories over China and around via satellite communication and to carry out time extrapolation forecast uniformly. To reduce data quantity, we first partition the data and encode them and then broadcast these information via navigation message to CAPS users’ receivers. Upon the interpolations being done in receivers, the reference air pressure and temperature at the receiver’s nearby place is derived. Lastly, combing with the receiver-observed real air pressure and temperature, the site’s altitude can be determined. The work is presented in the following aspects: the calculation principle, formulae, data collection, encoding, prediction, interpolation method, navigation message transmission together with errors causes and analyses. The advantages and shortcomings of the technique are discussed at the end.AI GuoXiang SHENG PeiXuan DU JinLin ZHENG YongGuang CAI XianDe WU HaiTao HU YongHui HUA Yu LI XiaoHui 2009Science China(Physics,Mechanics & Astronomy)2009,52,3:22
2Induction of apoptosis of human gastric carcinoma SGC-7901 cell line by 5,7-dihydroxy-8-nitrochrysin in vitro显示文摘AIM: To investigate the effect of 5, 7-dihydroxy-8- nitrochrysin (NOChR) on apoptosis of human gastric carcinoma SGC-7901 cell line. METHODS: SGC-7901 cells were cultured in vitro and the inhibitory effect of NOChR on proliferation of SGC-7901 cells was measured by using an MTT assay. NOChR-induced apoptosis rate of SGC-7901 cells was detected using flow cytometry (FCM) with PI staining. DNA ladder bands were observed by DNA agarose gel electrophoresis. The influence of NOChR on the proxisome proliferator-activated receptor-γ (PPARγ), Bcl-2 and Bax protein expression of SGC-7901 cells was analyzed by Western blot. RESULTS: MTT assay showed that NOChR markedly inhibited proliferation of SGC-7901 cells in a dose- dependent manner, and when IC50 was 4.14 μmol/L, the potency of NOChR was 10 times than that of lead compound, chrysin (ChR, IC50 was 40.56 μmol/L), and was similar to 5-fluorouracil (5-FU, IC50 was 4.51 μmol/L). FCM with propidium iodide (PI) staining demonstrated that the apoptosis rates of SGC-7901 cells treated with 1.25, 5.00 and 20.00 μmol/L NOChR for 48 h were 9.8% ± 0.2%, 36.8% ± 1.9% and 45.5% ± 3.5%, respectively, and were significantly higher when treated with 5.00 and 20.00 μmol/L NOChR than that with 20.00 μmol/L ChR (12.9% ± 1.5%). DNA agarose gel electrophoresis showed that treatment of SGC-7901 cells with 20.00 μmol/L NOChR for 48 h resulted in typical DNA ladder bands of DNA of SGC-7901 cells, which could be eliminated by treating with 10.00 μmol/L GW9662, a blocker of PPARγ. Western blot analysis revealed that after 24 h of treatment with 20.00 μmol/L NOChR, PPARgamma and Bax protein expression of SGC-7901 cells increased but Bcl-2 expression decreased; however, pre-incubation with 10.00 μmol/L GW9662 could efficiently antagonize and weaken the regulatory effect of 20.00 μmol/L NOChR on Bax and Bcl-2 protein expression of SGC-7901 cells. CONCLUSION: NOChR induces apoptosis of SGC-7901 cell lines by activating PPARγ and decreasing ratio of Bcl-2 to Bax.Xiao-Hong Ai Xing Zheng Xiao-Qing Tang Li Sun Yang-Qin Zhang Yong Qin Hua-Qing Liu Hong Xia Jian-Guo Cao 2007World Journal of Gastroenterology2007,13,28:22
3Nickel-exposed Workers in China: A Cohort Study显示文摘There are more than 50 000 workers in Jinchuan Group Co,Ltd(JNMC).Since all staff in JNMC are eligible for a medical examination every two years,only 23 484 nickel-exposed subjects who participated in medical examination were included in this study.Their data,collected from June 22,2011 to September 28,2012,in aBAI Ya Na YAGN Ai Min PU Hong Quan HE Jie CHENG Ning ZHENG Tong Zhang DAI Min ZHANG Ya Wei BASSING Bryan WANG Qiu Ying 2014Biomedical and Environmental Sciences2014,27,3:20
4Generation of a precise Oct4-hrGFP knockin cynomolgus monkey model via CRISPR/Cas9-assisted homologous recombination显示文摘Yiqiang Cui Yuyu Niu Jiankui Zhou Yongchang Chen Yiwei Cheng Shangang Li Zongyong Ai Chu Chu Hong Wang Bo Zheng Xuejin Chen Jiahao Sha Xuejiang Guo Xingxu Huang Weizhi Ji 2018Cell Research2018,28,3:13
5The role of Med19 in the proliferation and tumorigenesis of human hepatocellular carcinoma cells显示文摘Shao-wu ZOU Kai-xing AI Zhi-gang WANG Zhou YUAN Jun YAN Qi ZHENG 2011Acta Pharmacologica Sinica2011,32,3:12
6Nutrient Intakes of Pregnant Women and their Associated Factors in Eight Cities of China: A Cross-sectional Study显示文摘Fang-Li Liu Yu-Mei Zhang Gerard Vinyes Pares Kathleen C Reidy Wen-Zhi Zhao Ai Zhao Cheng Chen Celia Y Ning Ying-Dong Zheng Pei-Yu Wang 2015Chinese Medical Journal2015,,13:12
7Preparation of Li_4Ti_5O_(12) submicrospheres and their application as anode materials of rechargeable lithium-ion batteries显示文摘We report on the preparation of spinel Li4Ti5O12 submicrospheres and their application as anode materials of rechargeable lithium-ion batteries. The spinel Li4Ti5O12 submicrospheres are synthesized with three steps of the hydrolysis of TiCl4 to form rutile TiO2, the hydrothermal treatment of rutile TiO2 with LiOH to prepare an intermediate phase of LiTi2O4+δ, and the calcinations of LiTi2O4+δ to obtain spinel Li4Ti5O12. The as-prepared products are investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The diameters of Li4Ti5O12 submicrospheres with novel hierarchical microstructures are about 200–300 nm with the assembly of 20–30 nm nanoparticles. The electrochemical properties of Li4Ti5O12 submicrospheres are measured by galvanostatical discharge/charge test and cyclic voltammetry (CV). The as-prepared Li4Ti5O12 display excellent discharge/charge rate and cycling capability. A high discharge capacity of 174.3 mAh/g is obtained in the first discharge at 1 C rate. Meanwhile, there is only tiny capacity fading with nearly 100% columbic efficiency in the sequential 5–50 cycles. Moreover, lithium-ion diffusion coefficient in Li4Ti5O12 is calculated to be 1.03 × 10-7 cm2/s. The present results indicate that the as-prepared Li4Ti5O12 submicrospheres are promising anode candidates of rechargeable Li-ion batteries for high-power applications.ZHANG Ai, ZHENG ZongMin, CHENG FangYi, TAO ZhanLiang & CHEN Jun Key Laboratory of Advanced Energy Materials Chemistry, Ministry of Education College of Chemistry, Nankai University, Tianjin 300071, China 2011Science China Chemistry2011,54,6:9
8Effects of targeting magnetic drug nanoparticles on human cholangiocarcinoma xenografts in nude mice显示文摘BACKGROUND:Targeting is a new therapeutic tool for malignant tumor as a result of combining nanotechnology with chemotherapeutics.The aim of our study was to investigate the effects of magnetic nanoparticles enveloping a chemotherapeutic drug on human cholangiocarcinoma xenografts in nude mice. METHODS:The human cholangiocarcinoma xenograft model was established in nude mice with the QBC939 cell line.The nude mice were randomly assigned to 7 groups. 0.9%saline or magnetic nanoparticles,including high (group 2),medium(group 4)and low(group 5)dosages, were given to nude mice through the tail vein 20 days after the QBC939 cell line was implanted.Calculations were made 35 days after treatment in order to compare the volumes,inhibition ratios and growth curves of the tumors in each group.Mice in each group were sacrificed randomly to collect tumor tissues and other organs for electron microscopy and pathological examination. RESULTS:The high and medium dosage groups were significantly different from the control group(P<0.05). The tumor inhibition ratios for the high,medium and low dosage groups were 39.6%,14.6%and 7.9%,respectively. The tumor growth curve of groups 5,4,and 2 changed slowly in turn.The high and medium groups showed cell apoptosis under an electron microscope.CONCLUSION:Magnetic nanoparticles can inhibit the growth of human cholangiocarcinoma xenografts in nude mice.Tang, Tao Zheng, Jian-Wei Chen, Bo Li, Hong Li, Xi Xue, Ke-Ying Ai, Xing Zou, Sheng-Quan 2007Hepatobiliary & Pancreatic Diseases International2007,6,3:8
9Survey of coverage,strategy and cost of hepatitis B vaccination in rural and urban areas of China显示文摘INTRODUCTIONSomestudiesdemonstratedthatHBsAgandantiHBcpositiveratesoftheimmunizedpopulationsafterhepatitisB(HB)vaccination...ZENG Xian Jia 1, YANG Gong Huan 2, LIAO Su Su 1, CHEN Ai Ping 2, TAN Jian 2, HUANG Zheng Jing 2 and LI Hui 1 1999World Journal of Gastroenterology1999,5,4:8
10Ghrelin improves delayed gastrointestinal transit in alloxan-induced diabetic mice显示文摘AIM: To investigate the effects of ghrelin on delayed gastrointestinal transit in alloxan-induced diabetic mice. METHODS: A diabetic mouse model was established by intraperitoneal injection with alloxan. Mice were randomized into two main groups: normal mice group and diabetic mice group treated with ghrelin at doses of 0, 20, 50, 100 and 200 μg/kg ip. Gastric emptying (GE), intestinal transit (IT), and colonic transit (CT) were studied in mice after they had a phenol red meal following injection of ghrelin. Based on the most effective ghrelin dosage, atropine was given at 1 mg/kg 15 min before the ghrelin injection for each measurement. The mice in each group were sacrificed 20 min later and their stomachs, intestines, and colons were harvested immediately. The amount of phenol red was measured. Percentages of GE, IT, and CT were calculated. RESULTS: Percentages of GE, IT, and CT were significantly decreased in diabetic mice as compared to control mice (22.9 ± 1.4 vs 28.1 ± 1.3, 33.5 ± 1.2 vs 43.2 ± 1.9, 29.5 ± 1.9 vs 36.3 ± 1.6, P < 0.05). In the diabetic mice, ghrelin improved both GE and IT, but not CT. The most effective dose of ghrelin was 100 μg/kg and atropine blocked the prokinetic effects of ghrelin on GE and IT.CONCLUSION: Ghrelin accelerates delayed GE and IT but has no effect on CT in diabetic mice. Ghrelin may exert its prokinetic effects via the cholinergic pathway in the enteric nervous system, and therefore has therapeutic potential for diabetic patients with delayed upper gastrointestinal transit.Wen-Cai Qiu Zhi-Gang Wang Ran Lv Wei-Gang Wang Xiao-Dong Han Jun Yan Yu Wang Qi Zheng Kai-Xing Ai 2008World Journal of Gastroenterology2008,14,16:7
11Prevalence of Anti-endothelial Cell Antibodies in Patients with Pulmonary Arterial Hypertension Associated with Connective Tissue Diseases显示文摘Objective To investigate the prevalence of anti-endothelial cell antibodies (AECAs) in the sera of connective tissue diseases (CTD) patients with pulmonary arterial hypertension (PAH) and its correlation with clinical manifestations. Methods AECAs in sera of 39 CTD patients with PAH,22 CTD patients without PAH,and 10 healthy donors as controls were detected with Western blotting. The prevalence of different AECAs in different groups was compared and its correlation with clinical manifestations was also investigated. Results The prevalence of AECAs was 82.1% in CTD patients with PAH,72.7% in CTD patients without PAH,and 20.0% in healthy donors. Anti-22 kD AECA was only detected in CTD patients with PAH (15.4%). Anti-75 kD AECA was more frequently detected in CTD patients with PAH than in those without PAH (51.3% vs. 22.7%,P<0.05). In CTD patients with PAH,anti-75 kD AECA was more frequently detected in those with Raynaud’s phenomenon or with positive anti-RNP antibody. Conclusion AECAs could be frequently detected in CTD patients with or without PAH,while anti-22 kD and anti-75 kD AECA might be specific in CTD patients with PAH.Meng-tao Li Jun Ai Zhuang Tian Quan Fang Wen-jie Zheng Xue-jun Zeng Xiao-feng Zeng 2010Chinese Medical Sciences Journal2010,25,1:7
12Hijacking antibody-induced CTLA-4 lysosomal degradation for safer and more effective cancer immunotherapy显示文摘It remains unclear why the clinically used anti-CTLA-4 antibodies, popularly called checkpoint inhibitors, have severe immunotherapy-related adverse effects (irAEs) and yet suboptimal cancer immunotherapeutic effects (CITE). Here we report that while irAE-prone Ipilimumab and TremeIgG1 rapidly direct cell surface CTLA-4 for lysosomal degradation, the non-irAE-prone antibodies we generated, HL12 or HL32, dissociate from CTLA-4 after endocytosis and allow CTLA-4 recycling to cell surface by the LRBA-dependent mechanism. Disrupting CTLA-4 recycling results in robust CTLA-4 downregulation by all anti-CTLA-4 antibodies and confers toxicity to a non-irAE-prone anti-CTLA-4 mAb. Conversely, increasing the pH sensitivity of TremeIgG1 by introducing designed tyrosine-to-histidine mutations prevents antibody-triggered lysosomal CTLA-4 downregulation and dramatically attenuates irAE. Surprisingly, by avoiding CTLA-4 downregulation and due to their increased bioavailability, pH-sensitive anti-CTLA-4 antibodies are more effective in intratumor regulatory T-cell depletion and rejection of large established tumors. Our data establish a new paradigm for cancer research that allows for abrogating irAE while increasing CITE of anti-CTLA-4 antibodies.Yan Zhang Xuexiang Du Mingyue Liu Fei Tang Peng Zhang Chunxia Ai James K. Fields Eric J. Sundberg Olga S. Latinovic Martin Devenport Pan Zheng Yang Liu 2019Cell Research2019,29,8:6
13Validation of the China-PAR Equations for Cardio-cerebrovascular Risk Prediction in the Inner Mongolian Population显示文摘The objective of this study was to evaluate the usefulness of the China-PAR equations in predicting the 10-year risk of cardiovascular disease(CVD) in the Inner Mongolians population. A population-based, prospective cohort of 2,589 Mongolians were followed up from 2003 to 2012.Participants were categorized into 4 subgroups according to their 10-year CVD risks calculated using the China-PAR equations: < 5%, 5%-9.9%,10%-19.9%, and ≥ 20%. The China-PAR equations discriminated well with good C statistics(range,0.76-0.86). The adjusted hazard ratios for CVD showed an increasing trend among the 4 subgroups(P for trend < 0.01). However, the China-PAR equations underestimated the 10-year CVD risk in Mongolians, and the calibration was unsatisfactory(Hosmer-Lemeshow χ~2 = 19.98, P < 0.01 for men, χ~2 = 46.58, P < 0.001 for women). The performance of the China-PAR equations warrants further validation in other ethnic groups in China.ZENG Ni Mei ZHENG Xiao Wei PENG Hao JIAO Yang LI Hong Mei ZHANG Ming Zhi WANG Ai Li ZHANG Yong Hong 2018Biomedical and Environmental Sciences2018,31,6:6
14Clinical efficacy of gemcitabine and cisplatin-based transcatheter arterial chemoembolization combined with radiotherapy in hilar cholangiocarcinoma显示文摘BACKGROUND Radical surgical resection is regarded as the best treatment for hepatic hilar cholangiocarcinoma. However, 60%-70% of patients have lost the chance of surgery at the time of diagnosis. Simple biliary stent or drainage tube placement may fail in a short time due to tumor invasion or overgrowth, bile accumulation, or biofilm formation. Effective palliative treatments to extend the effective drainage time are of great significance for improving the quality of life of patients and changing the prognosis of patients. AIM To investigate the clinical efficacy of gemcitabine and cisplatin-based transcatheter arterial chemoembolization (TACE) combined with radiotherapy in hilar cholangiocarcinoma.METHODS A retrospective analysis was conducted on patients clinically diagnosed with hilar cholangiocarcinoma from June 2014 to January 2017 at the Liaoning Provincial Cancer Hospital. Patients were evaluated by specialists, and those who were not suitable for surgery or unwilling to undergo surgery and met the inclusion criteria were included in the study. There were a total of 72 patients (34 males and 38 females) with an average age of 59.9 years (range, 40-72 years). According to percutaneous transhepatic biliary angiography and the patients’ wishes, stent implantation or biliary drainage tube implantation was used to relieve biliary obstruction. The patients were divided into either a control group or a combined treatment group according to their follow-up treatment. The control group consisted of a total of 35 patients who received simple biliary drainage tube placement and biliary stent implantation (7 patients with bilateral stents and 6 with a unilateral stent) and 22 patients receiving biliary drainage tube placement alone. The combined treatment group received TACE and extracorporeal radiotherapy after biliary drainage or biliary stent implantation and consisted of a total of 37 patients, including 21 patients receiving combined treatment after biliary stent placement (14 patients with bilateral stents and 7 with a unilateral stent) and 16 undergoing combined therapy after implanting the biliary drainage tube. In the combination treatment group, the TACE chemotherapy regimen employed gemcitabine and cisplatin, and the embolic agent was iodized oil. A particular dose was determined according to the patient's body surface area and the tumor staining indicated by DSA. In vitro radiotherapy was performed with intensity-modulated radiotherapy or threedimensional conformal radiotherapy at an average dose of 48.3 Gy. Both groups were followed from stent implantation or drainage tube implantation until the patient quitted or died. The median length of follow-up observation was 13 mo. The differences in overall survival time and the effect of different jaundice reducing methods (single stent, double stent, or biliary drainage) on the patency time and survival time of biliary stents were compared between the two groups;the related factors affecting overall survival time were analyzed. RESULTS The median survival time of the control group was 10.5 mo;the median survival time of patients with biliary stent implantation and those with percutaneous biliary drainage was 9.6 mo and 11.4 mo, respectively, and there was no statistically significant difference between them. The median survival time of the combined treatment group was 20.0 mo, which was significantly higher than that of the control group (P < 0.05). Among patients in the combined treatment group, the median survival time of patients who underwent biliary stent implantation and those who accepted percutaneous biliary drainage before the combination therapy was 19.5 mo and 20.1 mo, respectively, and there was no significant difference between them. In the combination treatment group, the mean time of median stent patency was 15.6 mo, which was significantly higher than that of the control group (7.0 mo;P < 0.05). The independent factors affecting survival time included age, whether to receive combination therapy, percutaneous biliary drainage tube implantation, and Bismuth-Corlette classification as type IV. CONCLUSION Gemcitabine and cisplatin-based TACE combined with radiotherapy can prolong the survival of patients with hilar cholangiocarcinoma. Independent predictors of survival include selection of combination therapy, Bismuth-Corlette classification as type IV, selection of percutaneous biliary drainage tube implantation, and age.Wen-Heng Zheng Tao Yu Ya-Hong Luo Ying Wang Ye-Fu Liu Xiang-Dong Hua Jie Lin Zuo-Hong Ma Fu-Lu Ai Tian-Lu Wang 2019World Journal of Gastrointestinal Oncology2019,11,6:6
15A seismic model for crustal structure in North China Craton显示文摘We present a digital crustal model in North China Craton(NCC). The construction of crustal model is based on digitization of original seismic sounding profiles, and new results of three-dimensional structure images of receiver functions. The crustal model includes seismic velocity and thickness of crustal layers. The depths to Moho indicate a thinning crust ~30 km in the east areas and a general westward deepening to more than 40 km in the west. The P wave velocity varies from 2.0 to 5.6 km/s in the sedimentary cover,from 5.8 to 6.4 km/s in the upper crust, and from 6.5 to 7.0 km/s in the lower crust. By analyzing regional trends in crustal structure and links to tectonic evolution illustrated by typical profiles, we conclude that:(1) The delimited area by the shallowing Moho in the eastern NCC represents the spatial range of the craton destruction. The present structure of the eastern NCC crust retains the tectonic information about craton destruction by extension and magmatism;(2) The tectonic activities of the craton destruction have modified the crustal structure of the convergence boundaries at the northern and southern margin of the NCC;(3) The Ordos terrene may represent a relatively stable tectonic feature in the NCC, but with the tectonic remnant of the continental collision during the assembly of the NCC in the north-east area and the response to the lateral expansion of the Tibetan Plateau during the Cenozoic in the south-west.TianYu Zheng YongHong Duan WeiWei Xu YinShuang Ai 2017Earth and Planetary Physics2017,1,1:5
16Epidermal growth factor receptor mutation analysis in cytological specimens and responsiveness to gefitinib in advanced non-small cell lung cancer patients显示文摘Background: Epidermal growth factor receptor(EGFR) mutation is the key predictor of EGFR tyrosine kinase inhibitors(TKIs) efficacy in non-small cell lung cancer(NSCLC). We conducted this study to verify the feasibility of EGFR mutation analysis in cytological specimens and investigate the responsiveness to gefitinib treatment in patients carrying EGFR mutations.Methods: A total of 210 cytological specimens were collected for EGFR mutation detection by both direct sequencing and amplification refractory mutation system(ARMS). We analyzed EGFR mutation status by both methods and evaluated the responsiveness to gefitinib treatment in patients harboring EGFR mutations by overall response rate(ORR), disease control rate(DCR) and progression free survival(PFS).Results: Of all patients, EGFR mutation rate was 28.6%(60/210) by direct sequencing and 45.2%(95/210) by ARMS(P<0.001) respectively. Among the EGFR wild type patients tested by direct sequencing, 26.7% of them were positive by ARMS. For the 72 EGFR mutation positive patients treated with gefitinib, the ORR, DCR and median PFS were 69.4%, 90.2% and 9.3 months respectively. The patients whose EGFR mutation status was negative by direct sequencing but positive by ARMS had lower ORR(48.0% vs. 80.9%, P=0.004) and shorter median PFS(7.4 vs. 10.5 months, P=0.009) as compared with that of EGFR mutation positive patients by both detection methods. Conclusions: Our study verified the feasibility of EGFR analysis in cytological specimens in advanced NSCLC. ARMS is more sensitive than direct sequencing in EGFR mutation detection. EGFR Mutation status tested on cytological samples is applicable for predicting the response to gefitinib. Abundance of EGFR mutations might have an influence on TKIs efficacy.Lin Li Zijin Zhang Zhixin Bie Zheng Wang Ping Zhang Xin Nie Yuanming Li Hui Wang Bin Ai Gang Cheng 2015Chinese Journal of Cancer Research2015,27,3:5
17Prevalence of Metabolic Syndrome in Chinese Nickel-exposed Workers显示文摘The prevalence of metabolic syndrome(MS was investigated in Chinese nickel-exposed workers A total of 35 104 subjects were enrolled in this study.The age-adjusted prevalence of MS,BMI≥25diabetes,hypertension,and abnormal lipid was13.9%,29.5%,12.8%,27.5%,and 47.1%respectively.The prevalence of BMI≥25hyperglycemia,and hypertension increasedYANG Ai Min BAI Ya Na PU Hong Quan ZHENG Tong Zhang CHENG Ning LI Juan Sheng LI Hai Yan ZHANG Ya Wei DING Jiao SU Hui REN Xiao Wei HU Xiao Bin 2014Biomedical and Environmental Sciences2014,27,6:5
18Induction of Tetraploid Male Sterile Tagetes erecta by Colchicine Treatment and Its Application for Interspecific Hybridization显示文摘Tagetes erecta is an annual multifunctional plant which can be cultivated under a broad range of climatic conditions. Polyploidization and interspecific hybridization are applied to facilitate breeding cultivars of T. erecta with improved ornamental qualities. Colchicine treatment to the germinating seeds was proved to be a useful tool for chromosome doubling of the male sterile two-type line ‘M525AB', with the resulting frequency of polyploid seedlings ranging from 88.89%(following 0.05% w/v colchicine applied for a 3–6 h exposure period) to a maximum of100.00%(following 0.1% for 3–6 h, or 0.2% for 3 h). Morphological observation, stomatal size and density analysis, flow cytometric analysis and chromosome counting were conducted to identify the tetraploid plants. Distinctive morphological changes were observed in a notable proportion of polyploid plants. The colchicine-treated polyploid T. erecta plants showed dwarfed and more robust growth, thicker, larger and greener leaves, larger inflorescences and florets. The mutant plants identified through morphological observation all aligned as polyploid plants, thus morphological observation could be an effective method for the detection of polyploidy. The polyploid plants had significant larger stomata size over the abaxial leaf surface, whereas the density of stomata distribution was remarkably reduced. The survival rate of tetraploid cuttings(i.e. 38%)was greatly reduced compared to that of diploid plants. The fertility of tetraploid plants was also decreased, as shown by cross-pollination yields.Interspecific hybridizations between colchicine-induced tetraploid plants of a male sterile T. erecta line and the naturally tetraploid fully fertile Tagetes patula species resulted in hybrid progeny. Most of these hybrids displayed the dwarfed growth stature and compact, larger-flower morphology which is the typical ideotype of herbaceous flowers. Thus, polyploidization may be employed effectively as a means to facilitate interspecific hybridization, thereby contributing significantly to the improvement of quantitative traits of Tagetes spp.HE Yanhong SUN Yalin ZHENG Riru AI Ye CAO Zhe BAO Manzhu 2016Horticultural Plant Journal2016,2,5:5
19Skeletal myogenesis by human embryonic stem cells显示文摘我们检验了在一个 xeno 移植动物的细胞建模的人的胚胎的茎(hES ) 的 myogenic 潜力。这里,我们证明区分开来与 hES 房间的先锋能在成年环境经历 myogenesis 并且在 myogenic 系产生房间类型的一个范围。这研究提供 hES 房间能在 vivo 改革肌肉和卫星房间并且是为对待肌肉的另一种有希望的房间类型的直接证据除了另外的 myogenic 房间类型的退化混乱。房间研究(2006 ) 16:713-722。做 i:10.1038/sj .cr.7310080;出版联机 2006 年 6 月 20 日。Jun Ke Zheng Yi Wang Aditi Karandikar Qian Wang Hui Gai Ai Lian Liu Chao Peng Hui Zhen Sheng 2006Cell Research2006,16,8:4
20Saturated absorption of different layered Bi_2Se_3 films in the resonance zone显示文摘Here, we used the micro P-scan method to investigate the saturated absorption(SA) of different layered Bi_2Se_3 continuous films. Through resonance excitation, first, we studied the influence of the second surface state(SS) on SA. The second SS resonance excitation(~2.07 e V) resulted in a free carrier cross section that was 4 orders of magnitude larger than usual. At the same time, we found that the fast relaxation process of the massless Dirac electrons is much shorter than that of electrons in bulk states. Moreover, the second SS excitation resonance reduced the saturation intensity. Second, we studied the effect of the thickness on the SA properties of materials.The results showed that the saturation intensity was positively correlated to the thickness, the same as the modulation depth, and the thicker the Bi_2Se_3 film was, the less the second SS would influence it. This work demonstrated that by using Bi_2Se_3 as a saturable absorber through changing the thickness or excitation wavelength, a controllable SA could be achieved.JUN ZHANG TIAN JIANG TONG ZHOU HAO OUYANG CHENXI ZHANG ZHENG XIN ZHENYU WANG XIANG’AI CHENG 2018Photonics Research2018,6,10:3
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