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Liu ZC, Bao DE, Liu DL, Chen XS. Construction of a genetic linkage map and identification of QTL associated with growth traits in Malus sieversii. JOURNAL OF ENVIRONMENTAL BIOLOGY 2016; 37:1043-1047. [PMID: 29989734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
110 F(1) individuals of apple were obtained by crossing between a good quality cultivar'Red Fuji'ofMalus domestica and an accession'Hongrou Apple'ofMalus sieversi. Using Joinmap3.0, a molecular genetic linkage map of Malus sieversii was constructed by 175 SSR and 105 SRAP markers which were integrated into 17 linkage groups and spanned 1299.67cM in genome with an average distance of 4.6cM between the markers. By using interval mapping method,17 QTLs for eight growth traits of Malus sieversii were detected, including 2 QTLs for tree height on cl and c16, 2 QTLs for stem height on c7, 2 QTLs for stem thickness on c3, 2 QTLs for new shoot length on c15 and c16, 2 QTLs for new shoot diameter on c2, 3 QTLs for internode number on c1, c2 and c2, 2 QTLs for internode length on c 1 and c2, 2 QTLs for lenticel density on c17, respectively. The phenotypic variations explained by each QTL ranged from 10.15% to 41.66%, and their LOD values varied from 2.54 to 4.53, of which five QTLs were major effect genes (LOD≥3.5).
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Yang XF, Kuang YW, Liu YS, Zhang DB, Shao ZG, Yu HL, Hong XK, Feng JF, Chen XS, Wang XF. Carbon-based molecular devices: Fano effects controlled by the molecule length and the gate voltage. NANOSCALE 2016; 8:15712-15719. [PMID: 27528438 DOI: 10.1039/c6nr03451a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Fano effect is an important quantum phenomenon in mesoscopic systems, which arises from an interference between the localized state and the extended state. Here we observe an obvious Fano effect near the Fermi level in an all-carbon molecular device consisting of an acene molecule sandwiched between two zigzag graphene nanoribbon (ZGNR) electrodes. By increasing the length of the molecule, an extended state gradually evolves into a localized state. With the aid of the nearby extended state, a Fano effect is achieved. Using a gate voltage, we can easily tune the Fano effect induced by the single-transmission channel. When the spin degree of freedom is involved, the all-carbon device can show a half-metallic property with positive or negative 100% spin polarization at the Fermi level under the gate voltage; meanwhile the spin thermoelectric effect can also be enhanced.
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Chen W, Zhao SL, Holovko M, Chen XS, Dong W. Scaled Particle Theory for Multicomponent Hard Sphere Fluids Confined in Random Porous Media. J Phys Chem B 2016; 120:5491-504. [PMID: 27294670 DOI: 10.1021/acs.jpcb.6b02957] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The formulation of scaled particle theory (SPT) is presented for a quite general model of fluids confined in a random porous media, i.e., a multicomponent hard sphere (HS) fluid in a multicomponent hard sphere or a multicomponent overlapping hard sphere (OHS) matrix. The analytical expressions for pressure, Helmholtz free energy, and chemical potential are derived. The thermodynamic consistency of the proposed theory is established. Moreover, we show that there is an isomorphism between the SPT for a multicomponent system and that for a one-component system. Results from grand canonical ensemble Monte Carlo simulations are also presented for a binary HS mixture in a one-component HS or a one-component OHS matrix. The accuracy of various variants derived from the basic SPT formulation is appraised against the simulation results. Scaled particle theory, initially formulated for a bulk HS fluid, has not only provided an analytical tool for calculating thermodynamic properties of HS fluid but also helped to gain very useful insight for elaborating other theoretical approaches such as the fundamental measure theory (FMT). We expect that the general SPT for multicomponent systems developed in this work can contribute to the study of confined fluids in a similar way.
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Liang Y, Chen XS, Wu JY, Huang O, Zong Y, Nie LJ, Fang Q, He JR, Zhu L, Chen WG, Li YF, Shen KW. [Factors related to adjuvant ovarian function suppression in premenopausal breast cancer patients]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2016; 38:357-362. [PMID: 27188608 DOI: 10.3760/cma.j.issn.0253-3766.2016.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To analyze the applied condition of ovary function suppression (OFS) before and after joint analysis of TEXT and SOFT trials and SOFT trial, and to identify the relevant factors of OFS usage. METHODS The analysis was performed in premenopausal women with hormone receptor (HR) positive breast cancer receiving surgical treatment from Apr 2013 to Oct 2015 in Ruijin Hospital, Shanghai Jiaotong University School of Medicine. Adjuvant treatment strategy was made in the multidisciplinary team (MDT) meetings. We analyzed the applied condition of OFS before and after joint analysis, SOFT trial and its relevant factors. RESULTS Among 454 patients, 114 (25.1%) patients received OFS. Before the results of joint analysis came out, all the patients (38/38) received OFS together with tamoxifen (TAM); after the results came out, clinicians began to put OFS with exemestane into practice, among 76 patients, 41(53.9%) patients received OFS with exemestane while 35 (46.1%) patients received OFS together with TAM. Before the results of SOFT trial came out, 71 out of 310 (22.9%) patients received OFS while 43 out of 144 (29.9%) patients received OFS after that. No significant difference was found between the proportion of patients receiving OFS before and after the results of SOFT trial came out (P=0.112). Age, histological grade, pN status, Ki-67 status, molecular subtype and acceptance of chemotherapy were correlated with OFS treatment (P<0.05). Age, tumor grade and pN were independent significant predictors of OFS usage. CONCLUSIONS After the results of joint analysis came out, clinicians began to apply OFS with exemestane to premenopausal women with HR positive breast cancer. There is no significant difference between the proportion of patients receiving OFS before and after SOFT trial. Age, tumor grade and pN status are independent significant predictors of OFS treatment. Patients younger than 40, with histological grade Ⅱ or Ⅲ tumor and with pN1 or pN2 status are prone to receive OFS.
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Wu YF, He FL, Gu YQ, Chen XS, Chen L, Chen L, Zhang J, Wang ZG. Evaluation in vivo of autologous cell derived vein grafts based on tissue engineering concept. INT ANGIOL 2015; 34:495-501. [PMID: 25669621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
AIM Aim of the study was to construct and evaluate of autologous cell derived vein grafts based on tissue engineering concept. METHODS In this study, we constructed venous grafts (VGs) in 12 days based on tissue engineering concept. We draw out 8-12 mL of bone marrow from the intended recipient canines (N.=8) to culture and expand endothelial progenitor cells (EPCs). After having been labeled with PKH26-GL, the cells were seeded onto the luminal surface of decellularized scaffolds (DSs) with single, rotative method for 4 hours. Following static culture for 24-72 hours, the hybrids were implanted to recipient canine inferior vena cava. Non-seeded DSs (N.=4) were performed as control. RESULTS Angiography disclosed that patent number of test (control) group were 7/7 (2/4), 6/6 (2/2) and 4/4 (1/2) at postoperative 10 days, 4 weeks and 12 weeks, respectively. At 12 weeks, confluenced endothelial cells which covered the whole inner luminal surface of the explants were detected. Meanwhile, fibroblasts and α-actin positive cells in the matrices were found. PKH26-GL labeled EPCs sustained on the luminal surface accompanied by newly formed endothelial cells. However, the explants in both groups showed partial stenosis. CONCLUSION These results indicate that such constructed VGs based on autologous bone marrow-derived EPCs and porcine DSs are promising and deserve to further improvement and testing.
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Yang GQ, Ge KY, Chen JS, Chen XS. Selenium-related endemic diseases and the daily selenium requirement of humans. World Rev Nutr Diet 2015; 55:98-152. [PMID: 3287776 DOI: 10.1159/000415560] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Zhang T, Zhang GX, Han KP, Tang Y, Wang JY, Fan QC, Chen XS, Wei Y, Wang YJ. Molecular cloning and characterization, and prokaryotic expression of the GnRH1 gene obtained from Jinghai yellow chicken. GENETICS AND MOLECULAR RESEARCH 2015; 14:2831-49. [PMID: 25867433 DOI: 10.4238/2015.march.31.14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The gonadotropin-releasing hormone (GnRH) plays an important role in the control of reproductive functions. Recent studies have reported the occurrence of GnRH molecular variants in numerous species. In this study, the GnRH1 gene from Jinghai yellow chicken was cloned by reverse transcriptase-polymerase chain reaction and transformed into BL21 (DE3) competent cells. The GnRH1 gene and amino acid sequences were subjected to bioinformatic analyses. The GnRH1 gene nucleotide sequence was discovered to be 352 bp long, containing a coding, promoter, and section of the 3'-regions. The GnRH1 gene shared 93, 81, 54, 58, 61, 76, 76, 59, 76, and 66% sequence identity with Meleagris gallopavo, Columba livia, Homo sapiens, Bos taurus, swines, Capra hircus, Ovis aries, Pantholops hodgsonii, Equus caballus, and Rattus norvegicus, respectively. The GnRH1 gene showed conserved domains. The GnRH1 protein was a secreted protein comprising 92 amino acids, with a molecular weight of 10205.6 Da and a theoretical pI of 5.67. Most of the amino acid residues were observed to be hydrophilic, indicating water solubility. The predicted secondary structures of proteins included α-helices (h; 23.08%), β-extensions (e; 10.92%), and random coils (c; 66.0%). The successful construction of prokaryotic expression vector pET32a-GnRH1 was confirmed by restriction and sequence analysis. SDS-PAGE analysis showed the successful expression of recombinant plasmid in Escherichia coli BL21 (molecular weight = 25-28 kDa). Larger quantities of protein were expressed in supernatant, indicating greater expression in soluble form. Western blot analysis confirmed the expression of the target protein.
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Wu BH, Wang CR, Chen XS, Xu GJ. Current noise in three-terminal hybrid quantum point contacts. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:025301. [PMID: 24305057 DOI: 10.1088/0953-8984/26/2/025301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We investigate the current noise of three-terminal hybrid structures at arbitrary bias voltages. Our results indicate that the noise can be a useful tool to extract dynamical information in multi-terminal hybrid structures. The zero-frequency noise is sensitive to the coupling with a normal lead. As a result, the characteristic multiple-step structure of the noise Fano factor due to multiple Andreev reflection will be suppressed as we increase this coupling. In addition, the internal dynamics due to processes of Andreev reflection and multiple Andreev reflection raises rich features in the noise spectrum corresponding to the energy differences of various dynamical processes.
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Yao BM, Fu L, Chen XS, Lu W, Guo H, Gui YS, Hu CM. Ground penetrating detection using miniaturized radar system based on solid state microwave sensor. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:124702. [PMID: 24387449 DOI: 10.1063/1.4838662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We propose a solid-state-sensor-based miniaturized microwave radar technique, which allows a rapid microwave phase detection for continuous wave operation using a lock-in amplifier rather than using expensive and complicated instruments such as vector network analyzers. To demonstrate the capability of this sensor-based imaging technique, the miniaturized system has been used to detect embedded targets in sand by measuring the reflection for broadband microwaves. Using the reconstruction algorithm, the imaging of the embedded target with a diameter less than 5 cm buried in the sands with a depth of 5 cm or greater is clearly detected. Therefore, the sensor-based approach emerges as an innovative and cost-effective way for ground penetrating detection.
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Wang ZC, Shi JG, Chen XS, Xu GH, Li LJ, Jia LS. The role of smoking status and collagen IX polymorphisms in the susceptibility to cervical spondylotic myelopathy. GENETICS AND MOLECULAR RESEARCH 2012; 11:1238-44. [PMID: 22614351 DOI: 10.4238/2012.may.9.2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We investigated a possible association of collagen IX tryptophan (Trp) alleles (Trp2 and Trp3) and smoking with cervical spondylotic myelopathy (CSM) in 172 Chinese patients and 176 age- and gender-matched controls. The smoking status was evaluated by smoking index (SI). The CSM cases had a significantly higher prevalence of Trp2 alleles (Trp2+) than controls (19.8 vs 6.2%, P = 0.002), but the prevalence of Trp3 alleles (Trp3+) was similar between the two groups (23.3 vs 21.6%, P = 0.713). Logistic regression analyses showed that the subjects with Trp2+ had a higher risk for CSM. We thus analyzed whether smoking status influenced the association between Trp2 alleles and CSM risk. Among Trp2+ subjects with an SI less than 100, the smoking status did not influence the effect of risk for SCM [odds ratio (OR) = 1.34, 95% confidential interval (95%CI) = 0.85-2.18, P > 0.05]. When SI increased from 101 to 300, the OR for CSM reached 3.34 (95%CI = 2.11-5.67, P = 0.011); when SI was more than 300, the OR for CSM reached 5.56 (95%CI = 3.62-7.36, P < 0.001). Among Trp2- subjects with SI more than 300, the OR for CSM increased 2.14 (95%CI = 1.15-4.07, P = 0.024). We found a significant association between the Trp2 alleles and CSM risk and smoking amplifies this risk, suggesting that smoking abstinence is important for reducing CSM occurrence in subjects with high genetic risk.
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An FP, Bai JZ, Balantekin AB, Band HR, Beavis D, Beriguete W, Bishai M, Blyth S, Boddy K, Brown RL, Cai B, Cao GF, Cao J, Carr R, Chan WT, Chang JF, Chang Y, Chasman C, Chen HS, Chen HY, Chen SJ, Chen SM, Chen XC, Chen XH, Chen XS, Chen Y, Chen YX, Cherwinka JJ, Chu MC, Cummings JP, Deng ZY, Ding YY, Diwan MV, Dong L, Draeger E, Du XF, Dwyer DA, Edwards WR, Ely SR, Fang SD, Fu JY, Fu ZW, Ge LQ, Ghazikhanian V, Gill RL, Goett J, Gonchar M, Gong GH, Gong H, Gornushkin YA, Greenler LS, Gu WQ, Guan MY, Guo XH, Hackenburg RW, Hahn RL, Hans S, He M, He Q, He WS, Heeger KM, Heng YK, Hinrichs P, Ho TH, Hor YK, Hsiung YB, Hu BZ, Hu T, Hu T, Huang HX, Huang HZ, Huang PW, Huang X, Huang XT, Huber P, Isvan Z, Jaffe DE, Jetter S, Ji XL, Ji XP, Jiang HJ, Jiang WQ, Jiao JB, Johnson RA, Kang L, Kettell SH, Kramer M, Kwan KK, Kwok MW, Kwok T, Lai CY, Lai WC, Lai WH, Lau K, Lebanowski L, Lee J, Lee MKP, Leitner R, Leung JKC, Leung KY, Lewis CA, Li B, Li F, Li GS, Li J, Li QJ, Li SF, Li WD, Li XB, Li XN, Li XQ, Li Y, Li ZB, Liang H, Liang J, Lin CJ, Lin GL, Lin SK, Lin SX, Lin YC, Ling JJ, Link JM, Littenberg L, Littlejohn BR, Liu BJ, Liu C, Liu DW, Liu H, Liu JC, Liu JL, Liu S, Liu X, Liu YB, Lu C, Lu HQ, Luk A, Luk KB, Luo T, Luo XL, Ma LH, Ma QM, Ma XB, Ma XY, Ma YQ, Mayes B, McDonald KT, McFarlane MC, McKeown RD, Meng Y, Mohapatra D, Morgan JE, Nakajima Y, Napolitano J, Naumov D, Nemchenok I, Newsom C, Ngai HY, Ngai WK, Nie YB, Ning Z, Ochoa-Ricoux JP, Oh D, Olshevski A, Pagac A, Patton S, Pearson C, Pec V, Peng JC, Piilonen LE, Pinsky L, Pun CSJ, Qi FZ, Qi M, Qian X, Raper N, Rosero R, Roskovec B, Ruan XC, Seilhan B, Shao BB, Shih K, Steiner H, Stoler P, Sun GX, Sun JL, Tam YH, Tanaka HK, Tang X, Themann H, Torun Y, Trentalange S, Tsai O, Tsang KV, Tsang RHM, Tull C, Viren B, Virostek S, Vorobel V, Wang CH, Wang LS, Wang LY, Wang LZ, Wang M, Wang NY, Wang RG, Wang T, Wang W, Wang X, Wang X, Wang YF, Wang Z, Wang Z, Wang ZM, Webber DM, Wei YD, Wen LJ, Wenman DL, Whisnant K, White CG, Whitehead L, Whitten CA, Wilhelmi J, Wise T, Wong HC, Wong HLH, Wong J, Worcester ET, Wu FF, Wu Q, Xia DM, Xiang ST, Xiao Q, Xing ZZ, Xu G, Xu J, Xu J, Xu JL, Xu W, Xu Y, Xue T, Yang CG, Yang L, Ye M, Yeh M, Yeh YS, Yip K, Young BL, Yu ZY, Zhan L, Zhang C, Zhang FH, Zhang JW, Zhang QM, Zhang K, Zhang QX, Zhang SH, Zhang YC, Zhang YH, Zhang YX, Zhang ZJ, Zhang ZP, Zhang ZY, Zhao J, Zhao QW, Zhao YB, Zheng L, Zhong WL, Zhou L, Zhou ZY, Zhuang HL, Zou JH. Observation of electron-antineutrino disappearance at Daya Bay. PHYSICAL REVIEW LETTERS 2012; 108:171803. [PMID: 22680853 DOI: 10.1103/physrevlett.108.171803] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Indexed: 05/23/2023]
Abstract
The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.
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Feng X, Liu JJ, Zhou X, Song FH, Yang XY, Chen XS, Huang WQ, Zhou LH, Ye JH. Single sevoflurane exposure decreases neuronal nitric oxide synthase levels in the hippocampus of developing rats. Br J Anaesth 2012; 109:225-33. [PMID: 22535834 DOI: 10.1093/bja/aes121] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND The use of general anaesthetics in young children and infants has raised concerns regarding the adverse effects of these drugs on brain development. Sevoflurane might have harmful effects on the developing brain; however, these effects have not been well investigated. METHODS Postnatal day 7 (P7) Sprague-Dawley rats were continuously exposed to 2.3% sevoflurane for 6 h. We used the Fox battery test and Morris water maze (MWM) to examine subsequent neurobehavioural performance. Cleaved caspase-3 and neuronal nitric oxide synthase (nNOS) were quantified by immunoblotting, and the Nissl staining was used to observe the histopathological changes in the hippocampus. RESULTS A single 6 h sevoflurane exposure at P7 rats resulted in increased cleaved caspase-3 expression and decreased nNOS levels in the hippocampus, and induced the loss of pyramidal neurones in the CA1 and CA3 subfields of the hippocampus at P7-8. These changes were accompanied by temporal retardation of sensorimotor reflexes. However, neither the Fox battery test at P1-21 nor the MWM test at P28-32 showed differences between the air- and sevoflurane-treated groups. CONCLUSIONS Although early exposure to sevoflurane increases activated caspase-3 expression and neuronal loss and decreases nNOS in the neonatal hippocampus, it does not affect subsequent neurobehavioural performances in juvenile rats.
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Zhou J, Wang Q, Sun Q, Chen XS, Kawazoe Y, Jena P. Ferromagnetism in semihydrogenated graphene sheet. NANO LETTERS 2009; 9:3867-70. [PMID: 19719081 DOI: 10.1021/nl9020733] [Citation(s) in RCA: 169] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Single layer of graphite (graphene) was predicted and later experimentally confirmed to undergo metal-semiconductor transition when fully hydrogenated (graphane). Using density functional theory we show that when half of the hydrogen in this graphane sheet is removed, the resulting semihydrogenated graphene (which we refer to as graphone) becomes a ferromagnetic semiconductor with a small indirect gap. Half-hydrogenation breaks the delocalized pi bonding network of graphene, leaving the electrons in the unhydrogenated carbon atoms localized and unpaired. The magnetic moments at these sites couple ferromagnetically with an estimated Curie temperature between 278 and 417 K, giving rise to an infinite magnetic sheet with structural integrity and magnetic homogeneity. This is very different from the widely studied finite graphene nanostrucures such as one-dimensional nanoribbons and two-dimensional nanoholes, where zigzag edges are necessary for magnetism. From graphene to graphane and to graphone, the system evolves from metallic to semiconducting and from nonmagnetic to magnetic. Hydrogenation provides a novel way to tune the properties with unprecedented potentials for applications.
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Hong FC, Feng TJ, Cai YM, Wen LZ, Pan P, Lan LN, Lai YH, Zhou H, Liu XL, Lin SP, Chen G, Chen XS. Burden of syphilis infections in Shenzhen, China: a preliminary estimation. Int J STD AIDS 2009; 20:115-8. [DOI: 10.1258/ijsa.2008.008252] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Information on the prevalence and incidence of sexually transmitted infections is important for developing prevention and control strategies and allocating human and financial resources. However, there are no available estimates of such information for many areas in China. In this study, we used the existing data to make a preliminary estimation of syphilis infections in Shenzhen city, in south-eastern China. Data on prevalence rates of syphilis infections among different populations were obtained from the local HIV/sexually transmitted disease second-generation surveillance programme, and the sizes of different populations were estimated based on the most recently available figures. It was estimated that 83,760 (range 77,490–90,020) people are currently infected with syphilis, giving a prevalence of 0.71–0.82% (0.76% on average) in Shenzhen. Around 18% of these syphilis infections occur among men who have sex with men and another 15.8% and 8.7% occur among female sex workers and their clients, respectively. These estimates suggest that a combination of unprotected paid sex and sex between men may be sustaining the epidemic of syphilis in the study area. The preliminary estimates will assist the government in planning and improving its comprehensive intervention programmes for the future control and prevention of syphilis.
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Yin YP, Wong SPY, Liu MS, Wei WH, Yu YH, Gao X, Chen Q, Fu ZZ, Cheng F, Chen XS, Cohen MS. Improving strategies for syphilis control in China: selective testing of sexually transmitted disease patients--too little, too late? Int J STD AIDS 2008; 19:838-42. [PMID: 19050215 DOI: 10.1258/ijsa.2008.008088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
SUMMARY Syphilis testing guidelines in China are usually based on symptomatic criteria, overlooking risk assessment and ultimately opportunities for disease detection and control. We used data from 10,695 sexually transmitted disease (STD) clinic patients in Guangxi, China, to assess the efficacy of a potential screening tool inquiring about behavioural and health risk factors in identifying the STD patients who should not be triaged for syphilis testing under current guidelines, but on the contrary receive such testing. Validity testing of the screening tool was performed and receiver-operating characteristic curves were plotted to determine an optimal total risk score cut-off for testing. About 40.9% of patients with positive toluidine red unheated serum test and Treponema pallidum particle agglutination test did not show hallmark signs of syphilis. The screening tool was more sensitive in detecting infection in non-triaged male versus female patients (highest sensitivity = 90% vs. 55%) and the cut-off score to warrant testing was lower in non-triaged female patients than in non-triaged male patients (cut-off = 1 vs. 2). Most of the cases were missed among female STD patients. In spite of selective testing based on behavioural and health indicators that improve case detection, cases were still missed. Our study supports universal testing for syphilis in the STD population.
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Yang XF, Chen XS, Lu W, Fu Y. Effects of Shape and Strain Distribution of Quantum Dots on Optical Transition in the Quantum Dot Infrared Photodetectors. NANOSCALE RESEARCH LETTERS 2008; 3:534-539. [PMID: 20596318 PMCID: PMC2894248 DOI: 10.1007/s11671-008-9175-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2008] [Accepted: 09/11/2008] [Indexed: 05/29/2023]
Abstract
We present a systemic theoretical study of the electronic properties of the quantum dots inserted in quantum dot infrared photodetectors (QDIPs). The strain distribution of three different shaped quantum dots (QDs) with a same ratio of the base to the vertical aspect is calculated by using the short-range valence-force-field (VFF) approach. The calculated results show that the hydrostatic strain varepsilon(H) varies little with change of the shape, while the biaxial strain varepsilon(B) changes a lot for different shapes of QDs. The recursion method is used to calculate the energy levels of the bound states in QDs. Compared with the strain, the shape plays a key role in the difference of electronic bound energy levels. The numerical results show that the deference of bound energy levels of lenslike InAs QD matches well with the experimental results. Moreover, the pyramid-shaped QD has the greatest difference from the measured experimental data.
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Hong FC, Zhou H, Cai YM, Pan P, Feng TJ, Liu XL, Chen XS. Prevalence of syphilis and HIV infections among men who have sex with men from different settings in Shenzhen, China: implications for HIV/STD surveillance. Sex Transm Infect 2008; 85:42-4. [PMID: 18653567 DOI: 10.1136/sti.2008.031682] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
HIV/STD surveillance system data are important for developing prevention and control programmes for men who have sex with men (MSM), now a core group in Chinese HIV/STD surveillance activities. MSM were recruited from different settings in Shenzhen and were tested for HIV and syphilis. A substantial prevalence of HIV and syphilis infections was found in this population. However, risk behaviours and sociodemographic characteristics varied greatly among MSM recruited from the different settings (gay sauna, gay bar and MSM clinic), suggesting that carefully considering and selecting appropriate settings to represent the MSM population is critical for developing HIV and STD surveillance and prevention programmes.
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Yin YP, Chen XS, Wang HC, Shi MQ, Wei WH, Zhu BY, Yu YH, Tucker JD, Cohen MS. Detection of acute HIV infections among sexually transmitted disease clinic patients: a practice in Guangxi Zhuang Autonomous Region, China. Sex Transm Infect 2008; 84:350-1. [PMID: 18305121 DOI: 10.1136/sti.2007.028837] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Detection of people with acute HIV infection (AHI) affords an important opportunity for early HIV treatment and prevention. HIV RNA reverse transcriptase-polymerase chain reaction (RT-PCR) testing with two-stage pooling scheme was used to detect the AHI in specimens collected from sexually transmitted disease (STD) clinic patients in Guangxi, China. A total of 246 HIV RNA tests were required to screen 11 395 samples negative for conventional enzyme immunoassay (EIA) and Western blot assays, and five AHI cases (0.04%, 95%CI 0.02% to 0.10%) with a high viral load (median of 265,677 copies per ml) were detected. The total expenditure for RT-PCR testing reflected an added cost of $2.9 per specimen screened and $6575 per additional case of AHI identified among the study population. This study supports the feasibility of pooled RNA testing in addition to detection of HIV infections among patients at STD clinics in China, but the cost effectiveness should be carefully considered.
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Chen XS, Troiano N, Kacena M. β-Galactosidase detection as an indicator of endogenous PTHrP in cartilage. Biotech Histochem 2008; 83:89-96. [DOI: 10.1080/10520290802127834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Feng JR, Chen XS, Yuan ZH, Zhang LJ, Ci ZJ, Liu XL, Zhang CY. Primary molecular features of self-incompatible and self-compatible F(1) seedling from apricot (Prunus armeniaca L.) Katy x Xinshiji. Mol Biol Rep 2007; 36:263-72. [PMID: 17987401 DOI: 10.1007/s11033-007-9175-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2007] [Accepted: 10/30/2007] [Indexed: 11/29/2022]
Abstract
Expression of the S-RNase genes in the self-compatible (SC) apricot (Prunus armeniaca L.) cultivar Katy, the self-incompatible (SI) cultivar Xinshiji and their F(1) seedling was examined in this study. Three S-genotypes, S(9)Sc (Sc, self-compatibility S-gene absent from the style), S(8)S(9), and S(8)S(10), were obtained. Seedlings with S-RNase that migrated as a single band in gel electrophoresis were SC, despite high transcript abundance, and those with S-RNase that migrated as two bands were SI with high transcript abundance or SC with low transcript expression. S(8)-RNase was induced in SI cultivars only 24 h after self-pollination, indicating post-transcriptional regulation of S(8)-RNase in SI apricots. A Proteomic study showed that 35 protein spots were synthesized differently between SC and SI pistils. Fifteen of the 35 protein spots were identified; nine proteins, including receptor protein kinase-like protein, reversibly glycosylated polypeptide-2, and isoflavone reductase-like protein, were detected only in the SC pistils; while nine proteins, including actin 7, a putative serine/threonine kinase, and S-RNase, were detected only in the SI pistils. A mitochondrial NAD-dependent malate dehydrogenase and a probable elongation factor G were up-regulated, while heat shock cognate 70 was down-regulated in the SC pistils compared to those in the SI pistils. The results suggest that the proteins responsible for self-compatibility and self-incompatibility may be different.
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Yin YP, Peeling RW, Chen XS, Gong KL, Zhou H, Gu WM, Zheng HP, Wang ZS, Yong G, Cao WL, Shi MQ, Wei WH, Dai XQ, Gao X, Chen Q, Mabey D. Clinic-based evaluation of Clearview Chlamydia MF for detection of Chlamydia trachomatis in vaginal and cervical specimens from women at high risk in China. Sex Transm Infect 2006; 82 Suppl 5:v33-7. [PMID: 17121763 PMCID: PMC2563916 DOI: 10.1136/sti.2006.022475] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES To determine the performance of a rapid Chlamydia trachomatis (CT) test (Clearview Chlamydia MF) compared to the current "gold standard" (Roche Amplicor CT assay) test, and to assess acceptability of the tests to patients. METHODS A total of 1497 women at sexually transmitted diseases (STD) clinics or re-education centres in six urban cities (Shanghai, Nanjing, Shenzhen, Guangzhou, Chengdu and Fuzhou) in China participated in the study. Three vaginal and three cervical swabs were collected from each participant. Rapid CT tests were performed locally on the first vaginal and cervical swabs and the results were read independently by two staff members. The second and third swabs were randomised for performing the Roche CT assay at the National STD Reference Laboratory. Acceptability of the rapid tests to patients was determined by asking patients in clinics about their willingness to wait for the results. RESULTS The prevalence of CT was 13.2% (197/1497), as determined by the Roche assay with cervical specimens. CT was detected in 78 vaginal and 127 cervical specimens by the rapid test and the positive rates determined with cervical specimens were significantly higher than those with vaginal specimens (p<0.001). There was good agreement between the results read by two independent staff for either vaginal or cervical specimens (both kappa = 0.98, p<0.001). Sensitivities for vaginal and cervical specimens were 32.8% and 49.7%, respectively, and specificities were 99.2% and 97.9%, respectively. The positive predictive value was 85.7% for vaginal and 78.4% for cervical specimens. The vast majority of the patients (99.1%) were willing to wait up to two hours for the results. CONCLUSION Clearview Chlamydia MF, while yielding a rapid result and requiring minimal laboratory facilities, had unacceptably low sensitivity compared to a nucleic acid amplification test. Rapid tests yielding results within one hour are generally accepted by the clients.
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Chen XS, Yin YP, Mabey D, Peeling RW, Zhou H, Jiang WH, Wei WH, Yong G, Shi MQ, Chen Q, Gao X. Prevalence of Chlamydia trachomatis infections among women from different settings in China: implications for STD surveillance. Sex Transm Infect 2006; 82:283-4. [PMID: 16877575 PMCID: PMC2564709 DOI: 10.1136/sti.2006.019711] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Yin YP, Chen XS, Song B, Yao X, Hu ZJ, Li WZ. Performance of the Focus ELISA test for detection of herpes simplex virus type-2-specific antibodies in Chinese STD patients. Clin Microbiol Infect 2005; 11:423-4. [PMID: 15819876 DOI: 10.1111/j.1469-0691.2005.01113.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Dong W, Chen XS, Zheng WM. Thermodynamic pressure of a fluid confined in a random porous medium. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 72:012201. [PMID: 16090014 DOI: 10.1103/physreve.72.012201] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2004] [Revised: 12/09/2004] [Indexed: 05/03/2023]
Abstract
Up to now, none of the previously derived expressions is usable in simulations for the practical calculation of the thermodynamic pressure of a fluid adsorbed in a random porous medium. A bona fide virial expression of this pressure is presented. Contrary to what was believed, we show that this pressure is a measurable quantity and propose an experimental procedure for its measurement.
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Chen XS, Dohm V. Nonuniversal finite-size scaling in anisotropic systems. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2004; 70:056136. [PMID: 15600721 DOI: 10.1103/physreve.70.056136] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2004] [Indexed: 05/24/2023]
Abstract
We study the bulk and finite-size critical behavior of the O(n) symmetric phi4 theory with spatially anisotropic interactions of noncubic symmetry in d<4 dimensions. In such systems of a given (d,n) universality class, two-scale factor universality is absent in bulk correlation functions, and finite-size scaling functions including the Privman-Fisher scaling form of the free energy, the Binder cumulant ratio, and the Casimir amplitude are shown to be nonuniversal. In particular it is shown that, for anisotropic confined systems, isotropy cannot be restored by an anisotropic scale transformation.
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