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1Relationship between plasma D(-)-lactate and intestinal damage after severe injuries in rats显示文摘AIM To explore the kinetic changes in plasma D (-)lactate and lipopolysaccharide ( LPS ) levels, and investigate whether D (-)-lactate could be used as a marker of intestinal injury in rats following gut ischemia/reperfusion, burn, and acute necrotizing pancreatitis (ANP).METHODS Three models were developed in rats:gut ischemia/reperfusion obtained by one hour of superior severe burn injury created by 30% of total body surface induced by continuous inverse infusion of sodium taurocholate and trypsin into main pancreatic duct.Plasma levels of D( - )-lactate in systemic circulation and LPS in portal circulation were measured by enzymaticspectrophotometric method and limulus amebocyte lysate (LAL) test kit, respectively. Tissue samples of intestine were taken for histological analysis.RESULTS One hour gut ischemia followed by reperfusion injuries resulted in a significant elevation in plasma D( - )lactate and LPS levels, and there was a significant correlation between the plasma D( - )-lactate and LPS (r =0.719, P<0.05). The plasma concentrations of D(-)lactate and LPS increased significantly at 6 h postburn,and there was also a remarkable correlation between them (r = 0.877, P < 0.01). D ( - )-lactate and LPS levels elevated significantly at 2 h after ANP, with a similar significant correlation between the two levels (r-0.798,P < 0.01 ). The desquamation of intestine villi and infiltration of inflammatory cells in the lamina propria were observed in all groups.CONCLUSION The changes of plasma D( - )-lactate levels in systemic blood paralleled with LPS levels in the portal vein blood. The measurement of plasma D (-)-lactate level may be a useful marker to assess the intestinal injury and to monitor an increase of intestinal permeability and endotoxemia following severe injuries in early stage.Xiao-Qing Sun Xiao-Bing Fu Rong-Zhan Yi Lü Qun Deng Xiao-Guo Jian Zhi-Yong Sheng Bum Institute, 304~(th)Hospital,Beijing 100037,China Department of General Surgery,Chinese PLA 304 Hospital,Beijing 100037,China 2001World Journal of Gastroenterology2001,7,4:56
2Multiple genetic alterations and behavior of cellular biology in gastric cancer and other gastric mucosal lesions:H.pylori infection,histological types and staging显示文摘AIM To investigate the expression of multiplegenes and the behavior of cellular biology ingastric cancer(GC)and other gastric mucosallesions and their relations to Helicobacter pylori(H.pylori)infection,tumor staging andhistological subtypes.METHODS Three hundred and twenty-sevenspecimens of gastric mucosa obtained viaendoscopy or surgical resection,and ABCimmunohistochemical staining were used todetect the expression of p53,p16,Bcl-2 andCOX-2 proteins.H.pylori was determined byrapid urea test combined with pathologicalstaining or14C urea breath test.Cellular image analysis was performed in 66 patients withintestinal metaplasia(IM)and/or dysplasia(Dys).In 30 of them,both cancer and theparacancerous tissues were obtained at the timeof surgery.Histological pattern,tumor staging,lymph node metastasis,grading ofdifferentiation and other clinical data werestudied in the medical records.RESULTS p16 expression of IM or Dys wassignificantly lower in positive H.pylori chronicatrophic gastritis(CAG)than those withnegative H.pylori(CAG:54.8% vs 88.0%,IM:34.4% vs 69.6%,Dys:23.8% vs 53.6%,allP<0.05),Bcl-2 or COX-2 expression of IM orDys in positive H.pylori cases was significantlyhigher than that without H.pylori(Bcl-2:68.8%vs23.9%,90.5% vs 60.7%;COX-2:50.0% vs10.8%,61.8% vs 17.8%;all P<0.05).Themean number of most parameters of cellularimage analysis in positive H.pylori group wassignificantly higher than that in negative H.pylori group(Ellipser:53±14,40±12μm,Area1:748±572,302±202 μm2,Area2:3050±1661,1681±1990 μm2,all P<0.05;Ellipseb:79±23,58±15 μm,Ratio1:22%±5%,13%±4%,Ratio2:79%±17%,53%±20%,all P<0.01).There was significant correlation between Bcl-2and histologic pattern of gastric carcinoma,andbetween COX-2 and tumor staging or lymph nodemetastasis(Bcl-2:75.0% vs 16.7%;COX-2:76.0% vs 20.0%,79.2% vs 16.7%;allP<0.05).CONCLUSION p1l6, Bcl-2, and COX-2 but not p53 gene may play a role in the early genesis/ progression of gastric carcinoma and are associated with H. pylori infection. p53 gene is relatively late event in gastric tumorigenesis and mainly relates to its progression. There is more cellular-biological behavior of malignant tumor in gastric mucosal lesions with H. pylori infection. Aberrant Bcl-2 protein expression appears to be preferentially associated with the intestinal type cancer. COX-2 seems to be related to tumor staging and lymph node metastasis.Heng Jun Gao Lian Zhen Yu Jian Feng Bai Yan Shen Peng Gu Sun Han Lin Zhao Kun Miu Xiu Zhen Lü Xiao Yong Zhang Zhi Quan Zhao 2000World Journal of Gastroenterology2000,6,6:52
3Estrogen enhances the functions of CD4^(+)CD25^(+)Foxp3^(+) regulatory T cells that suppress osteoclast differentiation and bone resorption in vitro显示文摘Cross-talk has been shown to occur between the immune system and bone metabolism pathways.In the present study,we investigated the impact of CD4^(+)CD25^(+)Foxp3^(+) regulatory T(Treg)cells on osteoclastogenesis and bone resorption.Treg cells that were isolated and purified from peripheral blood mononuclear cells(PBMCs)of healthy adults inhibited both the differentiation of osteoclasts(OCs)from human embryo bone marrow cells(BMCs)and the pit formation in a dose-dependent manner.In cell cocultures,the production levels of both interleukin-10(IL-10)and transforming growth factor-beta 1(TGF-β1)were proportionally upregulated as the ratio of Treg cells to BMCs was increased,and the inhibition of OC differentiation and bone resorption by Treg cells was completely reversed by anti-IL-10 and anti-TGF-β1 antibodies.Treatment of BMC and Treg cell cocultures with 17β-estradiol(E2)at concentrations between 10^(-7) and 10^(-9) mol/l suppressed OC differentiation and bone resorption more efficiently than it did in cultures of BMCs alone;this enhanced suppression occurred via the stimulation of Treg cell IL-10 and TGF-b1 expression.These data suggest that Treg cells suppress OC differentiation and bone resorption by secreting IL-10 and TGF-β1.E2 enhances the suppressive effects of Treg cells on OC differentiation and bone resorption by stimulating IL-10 and TGF-β1 secretion from these cells.Therefore,Treg cell-derived IL-10 and TGF-b1 are likely involved in the regulation of E2 on bone metabolism and represent potential therapeutic targets for the treatment of postmenopausal osteoporosis(PMO).CY Luo L Wang C Sun DJ Li 2011Cellular & Molecular Immunology2011,8,1:33
4Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan显示文摘The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3, LI Jiliang1, SUN Shanxue1 & WANG Xinzheng1 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Institute of Geophysics, Chinese Seismological Bureau, Beijing 100081, China 3. Institute of Deposition Resource, Chinese Academy of Geological Sciences, Beijing 100037, China 2005Science China Earth Sciences2005,48,11:30
5Blockade of cholecystokinin-2 receptor and cyclooxygenase-2 synergistically induces cell apoptosis, and inhibits the proliferation of human gastric cancer cells in vitro显示文摘Gastrin and cyclooxygenase-2(COX-2) playimportant roles in the carcinogenesis and progression ofgastric cancer.However,it remains unknown whether the combination of cholecystokinin-2(CCK-2) receptor antagonist plus COX-2 inhibitor exerts synergistic anti-tumor effects on human gastric cancer.Here,we demonstrated that the combination of AG-041R(a CCK-2 receptor antagonist) plus NS-398(a selective COX-2 inhibitor) treatment had synergistic effects on proliferation inhibition,apoptosis induction,down-regulation of Bcl-2 and up-regulation of Bax expression in MKN-45 cells.These results indicate that simultaneous targeting of CCK-2 receptor and COX-2 may inhibit gastric cancer development more effectively than targeting either molecule alone.(C)2008 Elsevier Ireland Ltd.All rights reserved.Sun, W. H. 2008南京医科大学学报(自然科学版)2008,28,9:30
6Human mesenchymal stem cells overexpressing pigment epitheliumderived factor inhibit hepatocellular carcinoma in nude mice(摘要)显示文摘Gao, Y Yao, A Zhang, W Lu, S Yu, Y Deng, L Yin, A Xia, Y Sun, B Wang, X 2010南京医科大学学报(自然科学版)2010,30,8:25
7Vasculogenic mimicry is a prognostic factor for postoperative survival in patients with glioblastoma显示文摘A previous report has confirmed the existence and clinical significance of vasculogenic mimicry(VM)in glioma.However,its conclusions about the negative clinical significance of VM in glioblastoma are based on a small group of patients and,thus,might be unconvincing.The aim of the present study was to reevaluate the clinical significance of VM in glioblastoma.Patients were classified as VM-positive orWang SY Ke YQ Lu GH Song ZH Yu L Xiao S Sun XL Jiang XD Yang ZL Hu CC 2013中国神经肿瘤杂志2013,11,3:22
8Accuracy evaluation of a new three-dimensional reproduction method of edentulous dental casts, and wax occlusion rims with jaw relation显示文摘The article introduces a new method for three-dimensional reproduction of edentulous dental casts,and wax occlusion rims with jaw relation by using a commercial high-speed line laser scanner and reverse engineering software and evaluates the method’s accuracy in vitro.The method comprises three main steps:(i)acquisition of the three-dimensional stereolithography data of maxillary and mandibular edentulous dental casts and wax occlusion rims;(ii)acquisition of the three-dimensional stereolithography data of jaw relations;and(iii)registration of these data with the reverse engineering software and completing reconstruction.To evaluate the accuracy of this method,dental casts and wax occlusion rims of 10 edentulous patients were used.The lengths of eight lines between common anatomic landmarks were measured directly on the casts and occlusion rims by using a vernier caliper and on the three-dimensional computerized images by using the software measurement tool.The direct data were considered as the true values.The paired-samples t-test was used for statistical analysis.The mean differences between the direct and the computerized measurements were mostly less than 0.04 mm and were not significant(P.0.05).Statistical significance among 10 patients was assessed using one-way analysis of variance(P,0.05).The result showed that the 10 patients were considered statistically no significant.Therefore,accurate three-dimensional reproduction of the edentulous dental casts,wax occlusion rims,and jaw relations was achieved.The proposed method enables the visualization of occlusion from different views and would help to meet the demand for the computer-aided design of removable complete dentures.Fu-Song Yuan Yu-Chun Sun Yong Wang Pei-Jun L 2013International Journal of Oral Science2013,5,3:20
9The Impact of the Linked Factors of Provenance,Tectonics and Climate on Potash Formation:An Example from the Potash Deposits of Lop Nur Depression in Tarim Basin,Xinjiang,Western China显示文摘Potash deposits commonly accumulate in highly restricted settings at the final stage of brine evaporation. This does not mean that potash deposits are formed simply as a result of the evaporation concentration of seawater or lake water, but rather as a coupling result of particular provenance, tectonics and climate activities. In this paper, we focus on the formative mechanism of the potash deposits of Lop Nur depression in Tarim Basin to interpret the detailed coupling mechanism among provenance, tectonics and climate. In terms of the provenance of Lop Nur Lake, the water of the Tarim River which displays 'potassium-rich' characteristics play an important role. In addition, the Pliocene and Lower-Middle Pleistocene clastic beds surrounding Lop Nur Lake host a certain amount of soluble potassium and thus serves as 'source beds' for potash formation. During the late Pliocene, the Lop Nur region has declined and evolved into a great lake from the previous piedmont and diluvial fan area. Since the mid Pleistocene, the great-united Lop Nur Lake has been separated and has generated a chain system consisting of Taitema Lake, Big Ear Lake and Luobei Lake which has turned into the deepest sag in Lop Nur Lake. Dry climate in Lop Nur region has increased since the Pliocene, and became extreme at the late Pleistocene. The study implies that potash formation in Lop Nur Lake depends on the optimal combination of extreme components of provenance, tectonics and climate during a shorter-term period. The optimal patterns of three factors are generally characterized by the long-term accumulation and preliminary enrichment of potassium, the occurrence of the deepest sub-depression and the appearance of an extremely arid climate in Lop Nur region. These factors have been interacting synergistically since the forming of the saline lake and in the later stages strong 'vapor extraction' caused by extremely arid climate is needed to trigger large scale mineralization of potash deposits.LIU Chenglin JIAO Pengcheng Lü Fenglin WANG Yongzhi SUN Xiaohong ZHANG Hua WANG Licheng YAO Fojun 2015Acta Geologica Sinica(English Edition)2015,89,6:18
10Leber's hereditary optic neuropathy is associated with the mitochondrial ND4 G11696A mutation in five Chinese families显示文摘Zhou XT Wei QP Yang L Tong Y Zhao FX Lu CJ Qian YP Sun YH Lu F Qu J Guan MX 2006中国生物学文摘2006,20,4:18
11The effects of nitrogen fertilizer application on methane and nitrous oxide emission/uptake in Chinese croplands显示文摘The application of nitrogen(N) fertilizer to increase crop yields has a significant influence on soil methane(CH_4) and nitrous oxide(N_2O) emission/uptake.A meta-analysis was carried out on the effect of N application on(i) CH_4 emissions in rice paddies,(ii) CH_4 uptake in upland fields and(iii) N_2O emissions.The responses of CH_4 emissions to N application in rice paddies were highly variable and overall no effects were found.CH_4 emissions were stimulated at low N application rates(<100 kg N ha^(-1)) but inhibited at high N rates(>200 kg N ha^(-1)) as compared to no N fertilizer(control).The response of CH_4 uptake to N application in upland fields was 15%lower than control,with a mean CH_4 uptake factor of-0.001 kg CH_4-C kg^(-1) N.The mean N_2O emission factors were 1.00 and 0.94%for maize(Zea mays) and wheat(Triticum aestivum),respectively,but significantly lower for the rice(Oryza sativa)(0.51%).Compared with controls,N addition overall increased global warming potential of CH_4 and N_2O emissions by 78%.Our result revealed that response of CH_4 emission to N input might depend on the CH_4concentration in rice paddy.The critical factors that affected CH_4 uptake and N_2O emission were N fertilizer application rate and the controls of CH_4 uptake and N_2O emission.The influences of application times,cropping systems and measurement frequency should all be considered when assessing CH_4 and N_2O emissions/uptake induced by N fertilizer.SUN Bin-feng ZHAO Hong LU Yi-zhong Lü Fei WANG Xiao-ke 2016Journal of Integrative Agriculture2016,15,2:18
12Quantitative trait loci(QTLs)for quality traits related to protein and starch in wheat显示文摘Quality traits in wheat (Triticum aestivum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99–40.52% of phe- notypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster includ- ing protein and starch traits on chromosome 1D.Haiyan Sun Jianhua Lü Yuding Fan Yan Zhao Fanmei Kong Rijun Li Honggang Wang Sishen Li 2008Progress in Natural Science:Materials International2008,18,7:13
13High expression levels of IKK alpha and IKK beta are necessary for the malignant properties of liver cancer显示文摘IKK-NF-kappa B signaling is regarded as an important factor in hepatocarcinogenesis and a potential target for liver cancer therapy.Therefore,in this study,we analyzed the expression of mRNAs encoding components and targets of NF-kappa B signaling including IKK alpha,IKK beta,RANK,RANKL,OPG,CyclinD3,mammary serine protease inhibitor(Maspin),CyclinD1,c-FLIP,Bcl-x1,Stat3,Cip1 and Cip2 by real-time PCR in 40 patients with liver cancer.After statistical analysis,7 indices including IKK alpha,IKK beta,RANK,Maspin,c-FLIP,Cip2 and cyclinD1 were found to show significant differences between tumor tissue and its corresponding adjacent tissue.When IKK alpha and IKK beta were downregulated in the hepatocellular carcinoma(HCC) cell lines of MHCC-97L and MHCC-97H in vitro,the numbers of BrdU positive cells were decreased in both IKK alpha and IKK beta knockdown cells.Levels of apoptosis were also investigated in IKK alpha and IKK beta knockdown cells.The growth of HCC was inhibited in the subcutaneous implantation model,and lung metastatogenesis was also significantly inhibited in the kidney capsule transplantation model.Downregulation of IKK alpha and IKK beta in HCC cultured in vitro revealed that increased Maspin,OPG and RANKL expression was associated with metastasis of HCC.These findings were associated with downregulation of Bcl-XL and c-FLIP,which may be the reason for increased apoptosis.The therapeutic effect of IKK alpha and IKK beta downregulation depends on extent of NF-kappa B inhibition and the malignant nature of the HCC.We anticipate that IKK-targeted gene therapy can be used in the treatment of HCC,a cancer that is notoriously resistant to radiation and chemotherapy.Jiang,RQ Xia,YX Li,J Deng,L Zhao,L Shi,J Wang,XH Sun,BC Nanjing Med Univ,Liver Transplantat Ctr,Affiliated Hosp 1,Nanjing,Jiangsu Prov,Peoples R China Nanjing Med Univ,Ctr Canc,Nanjing,Jiangsu Prov,Peoples R China 2010南京医科大学学报(自然科学版)2010,30,5:13
14Mitochondrial Autophagy and NLRP3 Inflammasome in Pulmonary Tissues from Severe Combined Immunodeficient Mice after Cardiac Arrest and Cardiopulmonary Resuscitation显示文摘Jing-Jun Lyu Jawahar L Mehta Yi Li Lu Ye Sheng-Nan Sun Hong-Shuang Sun Jia-Chang Li Dong-Mei Zhang Jie Wei 2018Chinese Medical Journal2018,,10:12
15Preparation of modified Ce-SAPO-34 catalysts and their catalytic performances of methanol to olefins显示文摘The modified Ce-SAPO-34 catalysts were prepared with three methods, i.e., the liquid ion exchange with air calcination, impregnation with air calcination and impregnation with steam calcination methods. The catalytic performances of the catalysts for methanol to olefins were investigated. The properties of the catalysts were characterized using XRD, BET, XRF, FT-IR and NH3-TPD. The results indicated that compared to the SAPO-34 catalyst the catalyst prepared with the impregnation and air calcination prolonged the lifetime by 40 min and improved the selectivity to ethylene by 5% (mol) and the catalyst prepared with the impregnation and steam calcination showed the best modification effect, prolonging the lifetime by 70 min and improving the ethylene selectivity by 10% (mol). The catalyst prepared with the liquid ion exchange showed similar behaviour as the SAPO-34 catalyst. It was verified that the porous structure and surface acidity of these catalysts determined their catalytic behaviors.Shuxun Tian Shengfu Ji Dandan Lü Bingyang Bai Qi Sun 2013Journal of Energy Chemistry2013,22,4:10
16Periodicity and map for discovery of new ionic liquids显示文摘There is virtually no limit in the number of ionic liquids. How to select proper ones or discover new ones with desirable properties in such a large pool of ionic liquids? It has become a bottleneck in the researches and applications of ionic liquids. Mendeleev’s periodic law states that the properties of the elements vary periodically. Whether the similar regularity exists among ionic or mo-lecular fragments of compounds is an interesting topic. In this work, we attempted to establish a pe-riodicity and draw a “map” of ionic liquids for providing definite guidance to discover, design, and se-lect the proper ionic liquids rather than trial-and-error. If a complete regularity of the system of ionic liquids can be finally established in the future, we are near an epoch in understanding the existing differences and the reasons for the similarity of the ions or molecular fragments.ZHANG Suojiang, SUN Ning, ZHANG Xiangping & Lü Xingmei Research Laboratory for Green Chemical Engineering and Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China Correspondence should be addressed to Zhang Suojiang 2006Science China Chemistry2006,49,2:9
17Potent antitumor efficacy of an E1B 55kDa-deficient adenovirus carrying murine endostatin in hepatocellular carcinoma显示文摘Li G Sham J Yang J Su C Xue H Chua D Sun L Zhang Q Cui Z Wu M Qian Q 2005第二军医大学学报2005,26,11:9
18Opposite effects of nitrogen fertilization and plastic film mulching on crop N and P stoichiometry in a temperate agroecosystem显示文摘Aims Crop nitrogen(N)and phosphorus(P)stoichiometry can influence food nutritive quality and many ecosystem processes.However,how and why N and P stoichiometry respond to long-term agricul-tural management practices(e.g.N fertilization and film mulching)are not clearly understood.Methods We collected maize tissues(leaf,stem,root and seed)and soil sam-ples from a temperate cropland under 30-year continuous N fer-tilization and plastic film mulching treatments,measured their C,N and P concentrations(the proportion(%)relative to the sample mass),and used structural equation models to uncover the re-sponding mechanisms for crop N and P contents(the total amount(g/m2)in crop biomass).Important Findings Long-term N fertilization increased N concentrations in all crop tissues but sharply decreased P concentrations in vegetative tis-sues(leaf,stem and root),thereby reducing their C/N ratio and increasing C/P and N/P ratios.The drop in P concentration in vegetative tissues was due to the dilution effect by biomass in-crement and the priority of P supply for seed production.In con-trast,film mulching decreased N concentration but increased P concentrations in most crop tissues,thereby increasing C/N ratio and reducing C/P and N/P ratios.Film mulching increased crop P content by increasing soil temperature and moisture;whereas,mulching showed little effect on crop N content,because a posi-tive effects of soil temperature may have canceled out a negative effect by soil moisture.This indicated a decoupling of P and N uptake by crops under film mulching.In conclusion,N fertiliza-tion and plastic film mulching showed opposite effects of on crop N and P stoichiometry.Fan Ding Shuangyi Li Xiao-Tao Lü Feike A.Dijkstra Sean Schaeffer Tingting An Jiubo Pei Liangjie Sun Jingkuan Wang 2019Journal of Plant Ecology2019,12,4:8
19Effect of rare earth elements on the structures and mechanical properties of magnesium alloys显示文摘By means of first-principles calculations,we have investigated the effects of rare earth elements (REEs) on the structures and mechanical properties of magnesium.The lattice parameters,elastic constants,bulk moduli,shear moduli,Young's moduli and anisotropic parameter of these solid solutions have been calculated and analyzed.The nearest-neighbor distance between Mg and the REEs is also analyzed to explore the correlation with the bulk moduli.The results show that the 4f-electrons and atomic radii play an important role in the strengthening process.The anomalies of the lattice parameters and mechanical properties at Eu and Yb are due to the half-filled and full-filled 4f-electron orbital states.Finally,the increase of directional bonding character near the alloying elements may account for the anisotropy and brittleness of these magnesium alloys.L Zhong ZHOU Jian SUN ZhiMei CHEN RongShi 2013Science China(Technological Sciences)2013,56,3:8
20Superior grains determined by grain weight are not fully correlated with the flowering order in rice显示文摘Rice panicles are composed of many branches with two types of extreme grains,the superior and the inferior.Traditionally,it has been well accepted that earlier flowers result in superior grains and late flowers generate inferior grains.However,these correlations have never been strictly examined in practice.In order to determine the accurate relationship between superior and inferior grains and the flowering order,we localized all the seeds in a panicle in four distinct rice species and systematically documented the rice flowering order,flower locations and the final grain weight for their relationships.Our results demonstrated that the grain weight is more heavily determined by the position of the seeds than by the flowering order.Despite earlier flowering has a positive correlation with the grain weight in general,grains from flowers blooming on the second day after anthesis generally gained the highest weight.This suggests earlier flowers may not result in superior grains.Therefore,we concluded that superior and inferior grains,commonly determined by grain weight,are not fully correlated with the flowering order in rice.Following the order of the grain weight,the superior grains are generally localized at the middle parts of the primary branches,whereas inferior grains were mainly on the last two secondary branches of the lower half part of the panicle.In addition,the weight of inferior grains were affected by spikelet thinning and spraying with exogenous plant growth regulators,indicating that physiological incompetence might be the major reason for the occurrence of the inferior grains.PENG Ting L Qiang ZHAO Ya-fan SUN Hong-zheng HAN Ying-chun DU Yan-xiu ZHANG Jing LI Jun-zhou WANG Lin-lin ZHAO Quan-zhi 2015Journal of Integrative Agriculture2015,14,5:7
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