76
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Wen Z, Liao Q, Hu Y, You L, Zhou L, Zhao Y. A spheroid-based 3-D culture model for pancreatic cancer drug testing, using the acid phosphatase assay. Braz J Med Biol Res 2013; 46:634-42. [PMID: 23903680 PMCID: PMC3859338 DOI: 10.1590/1414-431x20132647] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 04/15/2013] [Indexed: 01/29/2023] Open
Abstract
Current therapy for pancreatic cancer is multimodal, involving surgery and
chemotherapy. However, development of pancreatic cancer therapies requires a
thorough evaluation of drug efficacy in vitro before animal
testing and subsequent clinical trials. Compared to two-dimensional culture of
cell monolayer, three-dimensional (3-D) models more closely mimic native
tissues, since the tumor microenvironment established in 3-D models often plays
a significant role in cancer progression and cellular responses to the drugs.
Accumulating evidence has highlighted the benefits of 3-D in
vitro models of various cancers. In the present study, we have
developed a spheroid-based, 3-D culture of pancreatic cancer cell lines
MIAPaCa-2 and PANC-1 for pancreatic drug testing, using the acid phosphatase
assay. Drug efficacy testing showed that spheroids had much higher drug
resistance than monolayers. This model, which is characteristically reproducible
and easy and offers rapid handling, is the preferred choice for filling the gap
between monolayer cell cultures and in vivo models in the
process of drug development and testing for pancreatic cancer.
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77
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Tongay S, Zhou J, Ataca C, Liu J, Kang JS, Matthews TS, You L, Li J, Grossman JC, Wu J. Broad-range modulation of light emission in two-dimensional semiconductors by molecular physisorption gating. NANO LETTERS 2013; 13:2831-6. [PMID: 23627637 DOI: 10.1021/nl4011172] [Citation(s) in RCA: 327] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In the monolayer limit, transition metal dichalcogenides become direct-bandgap, light-emitting semiconductors. The quantum yield of light emission is low and extremely sensitive to the substrate used, while the underlying physics remains elusive. In this work, we report over 100 times modulation of light emission efficiency of these two-dimensional semiconductors by physical adsorption of O2 and/or H2O molecules, while inert gases do not cause such effect. The O2 and/or H2O pressure acts quantitatively as an instantaneously reversible "molecular gating" force, providing orders of magnitude broader control of carrier density and light emission than conventional electric field gating. Physi-sorbed O2 and/or H2O molecules electronically deplete n-type materials such as MoS2 and MoSe2, which weakens electrostatic screening that would otherwise destabilize excitons, leading to the drastic enhancement in photoluminescence. In p-type materials such as WSe2, the molecular physisorption results in the opposite effect. Unique and universal in two-dimensional semiconductors, the effect offers a new mechanism for modulating electronic interactions and implementing optical devices.
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78
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Ma CY, Ma JL, Jiao YL, Li JF, Wang LC, Yang QR, You L, Cui B, Chen ZJ, Zhao YR. The plasma level of soluble receptor for advanced glycation end products is decreased in patients with systemic lupus erythematosus. Scand J Immunol 2012; 75:614-22. [PMID: 22324318 DOI: 10.1111/j.1365-3083.2012.02691.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In recent years, the role of high mobility group box-1 (HMGB1) protein and its receptors in autoimmune diseases has received increasing attention. It has been documented that HMGB1 is associated with disease activity in patients with systemic lupus erythematosus (SLE). This study was undertaken to determine the potential role of receptor for advanced glycation end products (RAGE), one receptor for HMGB1, in the pathogenesis of SLE. Plasma levels of soluble RAGE (sRAGE) from 105 patients with clinical diagnosis of SLE and 43 healthy controls were determined by ELISA. Associations between sRAGE levels and clinical, laboratory characteristics were assessed. The data showed that plasma levels of sRAGE in patients with SLE were significantly lower than those in healthy controls (HC) (P = 0.003). Plasma sRAGE in patients receiving short-period treatment showed an immediate decrease compared with the untreated patients (P = 0.023). In contrast, plasma sRAGE in patients receiving long-period treatment were significantly increased compared to those with short-period treatment (P = 0.000) and comparable with those in HC (P = 0.305). The significant decreased levels of sRAGE in patients with SLE suggest the potential association of RAGE signalling and SLE clinical pathology, whereas, long-period antilupus treatment may counteract the decreased sRAGE levels in patients with SLE.
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79
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Yu P, Luo W, Yi D, Zhang JX, Rossell MD, Yang CH, You L, Singh-Bhalla G, Yang SY, He Q, Ramasse QM, Erni R, Martin LW, Chu YH, Pantelides ST, Pennycook SJ, Ramesh R. Interface control of bulk ferroelectric polarization. Proc Natl Acad Sci U S A 2012; 109:9710-5. [PMID: 22647612 PMCID: PMC3382509 DOI: 10.1073/pnas.1117990109] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The control of material interfaces at the atomic level has led to novel interfacial properties and functionalities. In particular, the study of polar discontinuities at interfaces between complex oxides lies at the frontier of modern condensed matter research. Here we employ a combination of experimental measurements and theoretical calculations to demonstrate the control of a bulk property, namely ferroelectric polarization, of a heteroepitaxial bilayer by precise atomic-scale interface engineering. More specifically, the control is achieved by exploiting the interfacial valence mismatch to influence the electrostatic potential step across the interface, which manifests itself as the biased-voltage in ferroelectric hysteresis loops and determines the ferroelectric state. A broad study of diverse systems comprising different ferroelectrics and conducting perovskite underlayers extends the generality of this phenomenon.
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80
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Li J, Wang S, Liu H, You L. Preparation of Polycarbonate Hollow Microspheres by Microencapsulation Method. INT J POLYM MATER PO 2011. [DOI: 10.1080/00914037.2010.551358] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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81
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You L, Sheng ZY, Chen JY, Pan L, Chen L. The safety and efficacy of early-stage bi-weekly alendronate to improve bone mineral density and bone turnover in chinese post-menopausal women at risk of osteoporosis. J Int Med Res 2011; 39:302-10. [PMID: 21672334 DOI: 10.1177/147323001103900133] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The efficacy and safety of early, low frequency antiresorptive drug intervention for osteopaenia on bone mineral density (BMD) and bone turnover in Chinese post-menopausal women at risk of developing osteoporosis were investigated. A total of 180 women aged 40 - 70 years were enrolled and equally randomized to receive either 70 mg alendronate once every 2 weeks plus 0.5 μg alfacalcidol daily (treatment group) or alfacalcidol 0.5 μg daily alone (control group) for 12 months. In the treatment group, lumbar spine and total hip BMD at 12 months had increased significantly from baseline and compared with the control group. There were also significant reductions in serum levels of the bone turnover biomarkers, bone-specific alkaline phosphatase and C-terminal telopeptide of type I collagen, compared with the control. No serious adverse events were observed in either group and safety profiles were similar. It was concluded that early intervention with 70 mg alendronate once every 2 weeks was safe, well tolerated and more effective than alfacalcidol alone (control) in increasing BMD and reducing bone turnover, and might prevent serious outcomes, such as fragility fractures, reduce rates of adverse effects and improve patient compliance.
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82
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You L, Jiefu Y. The role of the polymorphism of CYP2C9 in patients with atrial fibrillation treated in warfarin anticoagulation therapy. BRITISH HEART JOURNAL 2011. [DOI: 10.1136/heartjnl-2011-300867.247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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83
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Zhang JX, He Q, Trassin M, Luo W, Yi D, Rossell MD, Yu P, You L, Wang CH, Kuo CY, Heron JT, Hu Z, Zeches RJ, Lin HJ, Tanaka A, Chen CT, Tjeng LH, Chu YH, Ramesh R. Microscopic origin of the giant ferroelectric polarization in tetragonal-like BiFeO(3). PHYSICAL REVIEW LETTERS 2011; 107:147602. [PMID: 22107234 DOI: 10.1103/physrevlett.107.147602] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2011] [Indexed: 05/12/2023]
Abstract
We report direct experimental evidence for a room-temperature, ∼130 μC/cm(2) ferroelectric polarization from the tetragonal-like BiFeO(3) phase. The physical origin of this remarkable enhancement of ferroelectric polarization has been investigated by a combination of x-ray absorption spectroscopy, scanning transmission electron microscopy, and first principles calculations. A large strain-induced Fe-ion displacement relative to the oxygen octahedra, combined with the contribution of Bi 6s lone pair electrons, is the mechanism driving the large ferroelectric polarization in this tetragonal-like phase.
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84
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Liu YC, Xu ZF, Jin GR, You L. Spin squeezing: transforming one-axis twisting into two-axis twisting. PHYSICAL REVIEW LETTERS 2011; 107:013601. [PMID: 21797542 DOI: 10.1103/physrevlett.107.013601] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Indexed: 05/31/2023]
Abstract
Squeezed spin states possess unique quantum correlation or entanglement and are significantly promising for advancing quantum information processing and quantum metrology. In recent back-to-back publications [C. Gross et al., Nature (London) 464, 1165 (2010) and Max F. Riedel et al., Nature (London) 464, 1170 (2010)], reduced spin fluctuations are observed leading to spin squeezing at -8.2 and -2.5 dB, respectively, in two-component atomic condensates exhibiting one-axis-twisting interactions. The noise reduction limit for the one-axis twisting scales as ∝1/N(2/3), which for a condensate with N∼10(3) atoms is about 100 times below the standard quantum limit. We present a scheme using repeated Rabi pulses capable of transforming the one-axis-twisting spin squeezing into the two-axis-twisting type, leading to Heisenberg limited noise reduction ∝1/N or an extra tenfold improvement for N∼10(3).
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85
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Li F, Liu X, Zhang L, You L, Wu H, Li X, Zhao J, Yu J. QSAR studies on the depuration rates of polycyclic aromatic hydrocarbons, polybrominated diphenyl ethers and polychlorinated biphenyls in mussels (Elliptio complanata). SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2011; 22:561-573. [PMID: 21732892 DOI: 10.1080/1062936x.2011.569947] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Based on the mechanism of action, a quantitative structure-activity relationship (QSAR) model for the depuration rate constants (k(d)) of 28 PAHs, 8 PBDEs and 28 PCBs in mussels (Elliptio complanata) was constructed by partial least squares (PLS) regression, following the guidelines for development and validation of QSAR models. For the training set of the QSAR model, r² = 0.953, the cross-validated regression coefficient (Q²(CUM)) was 0.947. The predicted log k(d) values for the validation set were consistent with the observed values, with a standard error (SE) of 0.160 log units and a squared correlation coefficient (Q²(EXT)) of 0.892. Comparatively, the developed QSAR model had good robustness, predictive ability and extended applicability domain. The electrophilicity index (ω), molecular polarizability (α), the averages of the negative potentials on the molecular surface (V(s⁻)) and the balance parameter of surface potential (τ) were the key parameters governing the log k(d) values in the QSAR model, which indicated that the log k(d) value was mainly related to the partition ability, electrostatic interactions, and van der Waals interactions of compounds.
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86
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Li J, Wang SJ, Liu HY, Wang SK, You L. Microencapsulation of sulfur in poly(urea-formaldehyde). J Appl Polym Sci 2011. [DOI: 10.1002/app.33899] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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87
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Lu TM, McDonald JF, Dabral S, Yang GR, You L, Bai P. Low Temperature Processing for Multilevel Interconnection and Packaging. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-181-55] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTThe future high density multilevel interconnection and packaging requires that the combination of the insulator and conductor layers has a low RC value. Thermal stress and diffusion during processing are issues of great concern in the high density multilevel structures. The problem can be alleviated by a proper choice of materials and processes that do not require high temperature. In this paper we propose to use parylene and its derivatives (dielectric constant 2.3–2.6) as the possible interlayer dielectrics and Cu (bulk resistivity ∼1.7 μ Ω-cm) as the conductor. Parylene can be vapor-deposited and cured at room temperature. The metallization of Cu has been achieved at room temperature using the newly developed partially ionized beam deposition technique. This technique has been shown to grow high quality metal films with low resistivity at low substrate temperatures. The interaction between Cu and parylene, including adhesion and diffusion, is also discussed.
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88
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You L, Yang GR, Lang CI, Wu P, Moore JA, McDonald JF, Lu TM. Vapor Deposition of Parylene Films from Precursors. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-282-593] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTParylene films, depending on the type, are thermally stable up to 530°C and have low dielectric constants ranging from 2.35 to 3.15. One of the most interesting properties of this material is its vapor depositability. Conventional vapor deposition involves cracking the parylene dimers at temperatures from 600 to 730 °C and polymerizingthe monomers at - 35 °C to RT. We have developed a simpler and less expensive technique that directly uses the precursors from which the dimers are made. This method requires the use of metal catalysts to produce parylene films. We have used the precursors α,α'-dibromo-p-xylene and dibromotetrafluoro-p-xylene to produce N-type and F-type parylene films. FTIR, XPS, thermal stability, and electrical studies show that the F-type parylene films grown from the precursors are comparable to, or sometimes better than, the films grown from dimer, and have potential microelectronics applications.
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89
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You L, Li L, Zhang F, Xu Q, Ren J. A pilot study of the clinical relevance of the relationship between the serum level of pregnancy-associated plasma protein A and the degree of acute coronary syndrome. J Int Med Res 2010; 38:625-32. [PMID: 20515576 DOI: 10.1177/147323001003800225] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Serum levels of pregnancy-associated plasma protein-A (PAPP-A), high-sensitivity C-reactive protein (hs-CRP) and tumour necrosis factor-alpha (TNF-alpha) were measured in 70 patients with acute coronary syndrome (ACS), comprising 18 with unstable angina (UA), 37 with acute myocardial infarction (AMI) and 15 with stable angina (SA); 15 healthy controls were also included. Levels of PAPP-A were significantly higher in the UA and AMI groups than in the SA and control groups. Levels of PAPP-A were similar in the SA and control groups, and higher in the ACS patients who were cardiac troponin T-negative (comprising UA and AMI patients) than in the control and SA groups. Levels of hs-CRP and TNF-alpha were significantly higher in the SA group than in the control group, significantly higher in the UA group than in the SA and control groups, and significantly higher in the AMI group than in all other groups. Levels of PAPP-A in ACS patients were positively correlated with levels of hs-CRP and TNF-alpha. It would seem, therefore, that PAPP-A is associated with inflammation and might be used to detect plaque instability and rupture before an increase in cardiac troponin T is detectable.
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90
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Lv H, Wang JC, Wu KL, Gao X, Wang LC, You L, Chen ZJ. Numb regulates meiotic spindle organisation in mouse oocytes. Reprod Fertil Dev 2010; 22:664-72. [PMID: 20353726 DOI: 10.1071/rd09236] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Accepted: 10/12/2009] [Indexed: 11/23/2022] Open
Abstract
Numb is an adaptor protein that controls the fate of cells in different species through asymmetrical inheritance by sibling cells during division. It has been investigated extensively in mitosis, mostly in neural progenitor cells, but its function in meiosis remains unknown. The present study was designed to investigate the expression, subcellular localisation and functional roles of Numb during mouse oocyte meiotic maturation. Using real-time polymerase chain reaction and western blotting, we found that the expression of Numb increased from the germinal vesicle (GV) to MII stages. Immunofluorescent staining revealed that Numb was mainly concentrated in the GV before meiosis resumption, aggregated in the vicinity of the chromosomes after GV breakdown and then localised to the spindle poles from prometaphase I to MII. Nocodazole treatment resulted in spindle destruction and Numb diffusion into the cytoplasm. However, Numb appeared at the spindle poles again once the spindles had formed when nocodazole-treated oocytes were washed and cultured for spindle recovery. Depletion of Numb by RNA interference resulted in chromosome misalignment, spindle deformation and even doubled spindle formation. Our results suggest that Numb is critical for spindle organisation during mouse oocytes meiosis. The present study provides evidence of a new function for Numb in addition to its action as a cell fate-determining factor.
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91
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Shi Y, Chen Z, Yan J, You L, Zhao Y. AC-018 Analysis of clinical characteristics in a large-scale study of Chinese women with polycystic ovary syndrome. Reprod Biomed Online 2008. [DOI: 10.1016/s1472-6483(10)61522-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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92
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Sun B, You L. Observing the Einstein-de Haas effect with atoms in an optical lattice. PHYSICAL REVIEW LETTERS 2007; 99:150402. [PMID: 17995144 DOI: 10.1103/physrevlett.99.150402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Indexed: 05/25/2023]
Abstract
The conservation of magnetization, or atomic spin angular momentum, is broken for anisotropic dipolar interactions. As a result, the Einstein-de Haas effect, or the transfer of spin to spatial angular momentum, arises because the total angular momentum is conserved. We identify the regime for observing this with two 87Rb atoms in a single well, stimulated by the recent result for a condensate. The two-atom system is found to be more easily observed and confirmed with the addition of a periodically modulated magnetic field. Our result of utilizing a feeble dipolar interaction may find potential applications in precision measurements.
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93
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Shi YH, Chen ZJ, You L, Zhao YR. Analysis of clinical data in a large-scale chinese women with polycystic ovary syndrome (PCOS). Fertil Steril 2007. [DOI: 10.1016/j.fertnstert.2007.07.626] [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]
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94
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Chang L, Zhai Q, Lu R, You L. Number fluctuation dynamics of atomic spin mixing inside a condensate. PHYSICAL REVIEW LETTERS 2007; 99:080402. [PMID: 17930933 DOI: 10.1103/physrevlett.99.080402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Indexed: 05/25/2023]
Abstract
We investigate the quantum dynamics of number fluctuations inside an atomic condensate during coherent spin mixing among internal states of the ground state hyperfine manifold, by quantizing the semiclassical nonrigid pendulum model in terms of the conjugate variable pair: the relative phase and the atom number. Our result provides a theoretical basis that resolves the resolution limit, or the effective "shot-noise" level, for counting atoms that is needed to clearly detect quantum correlation effects in spin mixing.
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95
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Reza F, Josephs E, Yuan F, Van Dyke B, Lin S, Feltz M, Chung H, Tian J, Heinz A, Tang N, O'Brien P, You L, Indurkhya S, Chandran K, Lakhani N, Lee J, LaBean T. Engineering novel synthetic biological systems. ACTA ACUST UNITED AC 2007. [DOI: 10.1049/iet-stb:20060004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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96
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Zhang P, Jen HH, Sun CP, You L. Angular momentum of a magnetically trapped atomic condensate. PHYSICAL REVIEW LETTERS 2007; 98:030403. [PMID: 17358664 DOI: 10.1103/physrevlett.98.030403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2005] [Revised: 09/12/2006] [Indexed: 05/14/2023]
Abstract
For an atomic condensate in an axially symmetric magnetic trap, the sum of the axial components of the orbital angular momentum and the hyperfine spin is conserved. Inside an Ioffe-Pritchard trap (IPT) whose magnetic field (B field) is not axially symmetric, the difference of the two becomes surprisingly conserved. In this Letter we investigate the relationship between the values of the sum or difference angular momentums for an atomic condensate inside a magnetic trap and the associated gauge potential induced by the adiabatic approximation. Our result provides significant new insight into the vorticity of magnetically trapped atomic quantum gases.
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97
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You L, Yin J. Evolutionary design on a budget: robustness and optimality of bacteriophage T7. ACTA ACUST UNITED AC 2006; 153:46-52. [PMID: 16986252 DOI: 10.1049/ip-syb:20050026] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Exploring how biological systems have been 'designed' by evolution to achieve robust behaviours is now a subject of increasing research effort. Yet, it still remains unclear how environmental factors may contribute to this process. This issue is addressed by employing a detailed computer model for the intracellular growth of phage T7. More than 150 000 in silico T7 mutants were generated and the rates and efficiencies of their growth in two host environments, namely, a realistic environment that offered finite host resources for the synthesis of phage functions and a hypothetical environment where the phage was supplied infinite host resources, were evaluated. Results revealed two key properties of phage T7. First, T7 growth was overall robust with respect to perturbations in its parameters, but fragile with respect to changes in the ordering of its genetic elements. Secondly, the wild-type T7 had close to optimal fitness in the finite environment. Furthermore, a strong correlation was found between fitness and growth efficiency in the finite environment. The results underscore the potential importance of the environment in shaping robust design of a biological system. In particular, the strong correlation between fitness and growth efficiency suggests that T7 may have evolved to maximise its growth rate by minimising waste of finite resources.
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98
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Sun B, Zhang WX, Yi S, Chapman MS, You L. Dipolar effect in coherent spin mixing of two atoms in a single optical lattice site. PHYSICAL REVIEW LETTERS 2006; 97:123201. [PMID: 17025962 DOI: 10.1103/physrevlett.97.123201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Indexed: 05/12/2023]
Abstract
We show that atomic dipolar effects are detectable in the system that recently demonstrated two-atom coherent spin dynamics within individual lattice sites of a Mott state. Based on a two-state approximation for the two-atom internal states and relying on a variational approach, we have estimated the spin dipolar effect. Despite the absolute weakness of the dipole-dipole interaction, it is shown that it leads to experimentally observable effects in the spin mixing dynamics.
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99
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Zhang M, Zhang P, Chapman MS, You L. Controlled splitting of an atomic wave packet. PHYSICAL REVIEW LETTERS 2006; 97:070403. [PMID: 17026215 DOI: 10.1103/physrevlett.97.070403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2005] [Indexed: 05/12/2023]
Abstract
We propose a simple scheme capable of adiabatically splitting an atomic wave packet using two independent translating traps. Implemented with optical dipole traps, our scheme allows a high degree of flexibility for atom interferometry arrangements and highlights its potential as an efficient and high fidelity atom optical beam splitter.
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100
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Thung E, Chou J, You L, Xu Z, Jablons D. Hypermethylation Silences Wnt Inhibitory Factor 1 in Nasopharyngeal Carcinoma. J Investig Med 2006. [DOI: 10.1177/108155890605401s28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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