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Saeed AI, Sharov V, White J, Li J, Liang W, Bhagabati N, Braisted J, Klapa M, Currier T, Thiagarajan M, Sturn A, Snuffin M, Rezantsev A, Popov D, Ryltsov A, Kostukovich E, Borisovsky I, Liu Z, Vinsavich A, Trush V, Quackenbush J. TM4: a free, open-source system for microarray data management and analysis. Biotechniques 2003; 34:374-8. [PMID: 12613259 DOI: 10.2144/03342mt01] [Citation(s) in RCA: 3723] [Impact Index Per Article: 169.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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Liang W, Bockrath M, Bozovic D, Hafner JH, Tinkham M, Park H. Fabry - Perot interference in a nanotube electron waveguide. Nature 2001; 411:665-9. [PMID: 11395762 DOI: 10.1038/35079517] [Citation(s) in RCA: 775] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The behaviour of traditional electronic devices can be understood in terms of the classical diffusive motion of electrons. As the size of a device becomes comparable to the electron coherence length, however, quantum interference between electron waves becomes increasingly important, leading to dramatic changes in device properties. This classical-to-quantum transition in device behaviour suggests the possibility for nanometer-sized electronic elements that make use of quantum coherence. Molecular electronic devices are promising candidates for realizing such device elements because the electronic motion in molecules is inherently quantum mechanical and it can be modified by well defined chemistry. Here we describe an example of a coherent molecular electronic device whose behaviour is explicitly dependent on quantum interference between propagating electron waves-a Fabry-Perot electron resonator based on individual single-walled carbon nanotubes with near-perfect ohmic contacts to electrodes. In these devices, the nanotubes act as coherent electron waveguides, with the resonant cavity formed between the two nanotube-electrode interfaces. We use a theoretical model based on the multichannel Landauer-Büttiker formalism to analyse the device characteristics and find that coupling between the two propagating modes of the nanotubes caused by electron scattering at the nanotube-electrode interfaces is important.
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Roelofs TA, Liang W, Latimer MJ, Cinco RM, Rompel A, Andrews JC, Sauer K, Yachandra VK, Klein MP. Oxidation states of the manganese cluster during the flash-induced S-state cycle of the photosynthetic oxygen-evolving complex. Proc Natl Acad Sci U S A 1996; 93:3335-40. [PMID: 11607649 PMCID: PMC39608 DOI: 10.1073/pnas.93.8.3335] [Citation(s) in RCA: 137] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Mn K-edge x-ray absorption spectra for the pure S states of the tetranuclear Mn cluster of the oxygen-evolving complex of photosystem II during flash-induced S-state cycling have been determined. The relative S-state populations in samples given 0, 1, 2, 3, 4, or 5 flashes were determined from fitting the flash-induced electron paramagnetic resonance (EPR) multiline signal oscillation pattern to the Kok model. The edge spectra of samples given 0, 1, 2, or 3 flashes were combined with EPR information to calculate the pure S-state edge spectra. The edge positions (defined as the zero-crossing of the second derivatives) are 6550.1, 6551.7, 6553.5, and 6553.8 eV for S0, S1, S2, and S3, respectively. In addition to the shift in edge position, the S0--> S1 and S1--> S2 transitions are accompanied by characteristic changes in the shape of the edge, both indicative of Mn oxidation. The edge position shifts very little (0.3 eV) for the S2--> S3 transition, and the edge shape shows only subtle changes. We conclude that probably no direct Mn oxidation is involved in this transition. The proposed Mn oxidation state assignments are as follows: S0 (II, III, IV, IV) or (III, III, III, IV), S1 (III, III, IV, IV), S2 (III, IV, IV, IV), S3 (III, IV, IV, IV).
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Bockrath M, Liang W, Bozovic D, Hafner JH, Lieber CM, Tinkham M, Park H. Resonant electron scattering by defects in single-walled carbon nanotubes. Science 2001; 291:283-5. [PMID: 11209073 DOI: 10.1126/science.291.5502.283] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We report the characterization of defects in individual metallic single-walled carbon nanotubes by transport measurements and scanned gate microscopy. A sizable fraction of metallic nanotubes grown by chemical vapor deposition exhibits strongly gate voltage-dependent resistance at room temperature. Scanned gate measurements reveal that this behavior originates from resonant electron scattering by defects in the nanotube as the Fermi level is varied by the gate voltage. The reflection coefficient at the peak of a scattering resonance was determined to be about 0.5 at room temperature. An intratube quantum dot device formed by two defects is demonstrated by low-temperature transport measurements.
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Ren F, Zhu Z, Qian X, Liang W, Mu P, Sun H, Liu J, Li A. Novel thiophene-bearing conjugated microporous polymer honeycomb-like porous spheres with ultrahigh iodine uptake. Chem Commun (Camb) 2016; 52:9797-800. [DOI: 10.1039/c6cc05188j] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We demonstrated novel honeycomb-like porous spherical conjugated microporous polymers bearing thiophene units with ultrahigh iodine uptake.
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Qian X, Zhu ZQ, Sun HX, Ren F, Mu P, Liang W, Chen L, Li A. Capture and Reversible Storage of Volatile Iodine by Novel Conjugated Microporous Polymers Containing Thiophene Units. ACS APPLIED MATERIALS & INTERFACES 2016; 8:21063-21069. [PMID: 27458782 DOI: 10.1021/acsami.6b06569] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Conjugated microporous polymers having thiophene building blocks (SCMPs), which originated from ethynylbenzene monomers with 2,3,5-tribromothiophene, were designedly synthesized through Pd(0)/CuI catalyzed Sonogashira-Hagihara cross-coupling polymerization. The morphologies, structure and physicochemical properties of the as-synthesized products were characterized through scanning electron microscope (SEM), thermogravimeter analysis (TGA), (13)C CP/MAS solid state NMR and Fourier transform infrared spectroscope (FTIR) spectra. Nitrogen sorption-desorption analysis shows that the as-synthesized SCMPs possesses a high specific surface area of 855 m(2) g(-1). Because of their abundant porosity, π-conjugated network structure, as well as electron-rich thiophene building units, the SCMPs show better adsorption ability for iodine and a high uptake value of 222 wt % was obtained, which can compete with those nanoporous materials such as silver-containing zeolite, metal-organic frameworks (MOFs) and conjugated microporous polymers (CMPs), etc. Our study might provide a new possibility for the design and synthesis of functional CMPs containing electron-rich building units for effective capture and reversible storage of volatile iodine to address environmental issues.
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Levy DE, Lapierre F, Liang W, Ye W, Lange CW, Li X, Grobelny D, Casabonne M, Tyrrell D, Holme K, Nadzan A, Galardy RE. Matrix metalloproteinase inhibitors: a structure-activity study. J Med Chem 1998; 41:199-223. [PMID: 9457244 DOI: 10.1021/jm970494j] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Modifications around the dipeptide-mimetic core of a hydroxamic acid based matrix metalloproteinase inhibitor were studied. These variations incorporated a variety of natural, unnatural, and synthetic amino acids in addition to modifications of the P1' and P3' substituents. The results of this study indicate the following structural requirements: (1) Two key hydrogen bonds must be present between the enzyme and potent substrates. (2) Potent inhibitors must possess strong zinc-binding functionalities. (3) The potential importance of the hydrophobic group at position R3 as illustrated by its ability to impart greater relative potency against stromelysin when larger hydrophobic groups are used. (4) Requirements surrounding the nature of the amino acid appear to be more restrictive for stromelysin than for neutrophil collagenase, 72 kDa gelatinase, and 92 kDa gelatinase. These requirements may involve planar fused-ring aryl systems and possibly hydrogen-bonding capabilities.
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Li A, Liang W, Hughes R. The effect of carbon monoxide and steam on the hydrogen permeability of a Pd/stainless steel membrane. J Memb Sci 2000. [DOI: 10.1016/s0376-7388(99)00223-9] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Long J, Huang G, Liang W, Liang B, Chen Q, Xie J, Jiang J, Su L. The prevalence of schizophrenia in mainland China: evidence from epidemiological surveys. Acta Psychiatr Scand 2014; 130:244-56. [PMID: 24916190 DOI: 10.1111/acps.12296] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/12/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Schizophrenia is a severe mental disorder. Its prevalence appears inconsistent in different regions of China; thus, we conducted this meta-analysis to estimate the prevalence of schizophrenia in mainland China. METHOD Studies on the prevalence of schizophrenia in mainland China were identified from electronic databases up to July 2013. Meta-analysis was used for prevalence of schizophrenia estimate. RESULTS For lifetime prevalence of schizophrenia, prevalence of 5.44 per 1000 (overall), 5.33 per 1000 (males), 5.51 per 1000 (females), 6.60 per 1000 (urban) and 4.73 per 1000 (rural) were estimated; there was no significant difference between males and females, while prevalence for urban dwellers was higher than for rural (OR=1.44, 95%CI: 1.30-1.59). For point prevalence of schizophrenia, prevalence of 4.62 per 1000 (overall), 4.63 per 1000 (males), 4.95 per 1000 (females), 5.15 per 1000 (urban) and 4.44 per 1000 (rural) were estimated; no statistical difference was found in males and females, but prevalence for urban dwellers was higher than for rural (OR=1.20; 95%CI: 1.02-1.41). CONCLUSION The prevalence estimate results were consistent with the international prevalence estimate of schizophrenia in mainland China. There was no significant difference between males and females, while prevalence for urban dwellers was higher than for rural.
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Liang W, Shediac-Rizkallah MC, Celentano DD, Rohde C. A population-based study of age and gender differences in patterns of health-related behaviors. Am J Prev Med 1999; 17:8-17. [PMID: 10429747 DOI: 10.1016/s0749-3797(99)00040-9] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Most research on preventive health behaviors has focused on individual rather than groups of behaviors. This study examined interrelationships among multiple preventive health behaviors in different age and gender groups. METHODS From 1990 to 1992, Maryland residents were surveyed by telephone through the Behavioral Risk Factor Surveillance System. The study sample of 4455 was divided into 8 groups based on age (18-24, 25-39, 40-54, and 55+) and gender. Correlation and oblique rotated factor analyses were used to examine patterns of 8 to 11 preventive health behaviors in each age-gender group. RESULTS Medical checkup and cholesterol test formed one behavioral cluster in the four male age groups. Breast and cervical cancer screening (mammogram, clinical breast examination [CBE], and Pap Smear) did not form one cluster until age 55 or older; Pap smear, CBE formed one cluster for women of all ages. Risk-taking behaviors were only prominent in the youngest age group: Seatbelt non-use, smoking, and drinking formed one cluster in younger males, and drinking and driving after drinking clustered in younger females. CONCLUSION Screening and risk-taking behaviors form distinct groups, and behavioral patterns differ by age and gender. Public health programs should consider multi-behavioral approaches, and be sensitive to the gender and age of the target population.
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Liang W, Lin C, Yuan L, Chen L, Guo P, Li P, Wang W, Zhang X. Preactivation of Notch1 in remote ischemic preconditioning reduces cerebral ischemia-reperfusion injury through crosstalk with the NF-κB pathway. J Neuroinflammation 2019; 16:181. [PMID: 31526384 PMCID: PMC6747758 DOI: 10.1186/s12974-019-1570-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 08/29/2019] [Indexed: 12/21/2022] Open
Abstract
Background Remote ischemic preconditioning (RIPC) initiates endogenous protective pathways in the brain from a distance and represents a new, promising paradigm in neuroprotection against cerebral ischemia-reperfusion (I/R) injury. However, the underlying mechanism of RIPC-mediated cerebral ischemia tolerance is complicated and not well understood. We reported previously that preactivation of Notch1 mediated the neuroprotective effects of cerebral ischemic preconditioning in rats subjected to cerebral I/R injury. The present study seeks to further explore the role of crosstalk between the Notch1 and NF-κB signaling pathways in the process of RIPC-induced neuroprotection. Methods Middle cerebral artery occlusion and reperfusion (MCAO/R) in adult male rats and oxygen-glucose deprivation and reoxygenation (OGD/R) in primary hippocampal neurons were used as models of I/R injury in vivo and in vitro, respectively. RIPC was induced by a 3-day procedure with 4 cycles of 5 min of left hind limb ischemia followed by 5 min of reperfusion each day before MCAO/R. Intracerebroventricular DAPT injection and sh-Notch1 lentivirus interference were used to inhibit the Notch1 signaling pathway in vivo and in vitro, respectively. After 24 h of reperfusion, neurological deficit scores, infarct volume, neuronal apoptosis, and cell viability were assessed. The protein expression levels of NICD, Hes1, Phospho-IKKα/β (p-IKK α/β), Phospho-NF-κB p65 (p-NF-κB p65), Bcl-2, and Bax were assessed by Western blotting. Results RIPC significantly improved neurological scores and reduced infarct volume and neuronal apoptosis in rats subjected to I/R injury. OGD preconditioning significantly reduced neuronal apoptosis and improved cell viability after I/R injury on days 3 and 7 after OGD/R. However, the neuroprotective effect was reversed by DAPT in vivo and attenuated by Notch1-RNAi in vitro. RIPC significantly upregulated the expression of proteins related to the Notch1 and NF-κB pathways. NF-κB signaling pathway activity was suppressed by a Notch1 signaling pathway inhibitor and Notch1-RNAi. Conclusions The neuroprotective effect of RIPC against cerebral I/R injury was associated with preactivation of the Notch1 and NF-κB pathways in neurons. The NF-κB pathway is a downstream target of the Notch1 pathway in RIPC and helps protect focal cerebral I/R injury.
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Sun H, Li A, Zhu Z, Liang W, Zhao X, La P, Deng W. Superhydrophobic activated carbon-coated sponges for separation and absorption. CHEMSUSCHEM 2013; 6:1057-1062. [PMID: 23650204 DOI: 10.1002/cssc.201200979] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 03/13/2013] [Indexed: 05/28/2023]
Abstract
Highly porous activated carbon with a large surface area and pore volume was synthesized by KOH activation using commercially available activated carbon as a precursor. By modification with polydimethylsiloxane (PDMS), highly porous activated carbon showed superhydrophobicity with a water contact angle of 163.6°. The changes in wettability of PDMS- treated highly porous activated carbon were attributed to the deposition of a low-surface-energy silicon coating onto activated carbon (confirmed by X-ray photoelectron spectroscopy), which had microporous characteristics (confirmed by XRD, SEM, and TEM analyses). Using an easy dip-coating method, superhydrophobic activated carbon-coated sponges were also fabricated; those exhibited excellent absorption selectivity for the removal of a wide range of organics and oils from water, and also recyclability, thus showing great potential as efficient absorbents for the large-scale removal of organic contaminants or oil spills from water.
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Maura F, Petljak M, Lionetti M, Cifola I, Liang W, Pinatel E, Alexandrov LB, Fullam A, Martincorena I, Dawson KJ, Angelopoulos N, Samur MK, Szalat R, Zamora J, Tarpey P, Davies H, Corradini P, Anderson KC, Minvielle S, Neri A, Avet-Loiseau H, Keats J, Campbell PJ, Munshi NC, Bolli N. Biological and prognostic impact of APOBEC-induced mutations in the spectrum of plasma cell dyscrasias and multiple myeloma cell lines. Leukemia 2018; 32:1044-1048. [PMID: 29209044 PMCID: PMC5886048 DOI: 10.1038/leu.2017.345] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Liang W, Hopper JE, Rowley JD. Karyotypic abnormalities and clinical aspects of patients with multiple myeloma and related paraproteinemic disorders. Cancer 1979; 44:630-44. [PMID: 113076 DOI: 10.1002/1097-0142(197908)44:2<630::aid-cncr2820440233>3.0.co;2-g] [Citation(s) in RCA: 75] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Karyotypic abnormalities were detected in the malignant cells of 6 of 18 patients with multiple myeloma (MM). Six patients with benign monoclonal gammopathy, one with amyloidosis of immunoglobulin origin, and two with Waldenström's macroglobulinemia had normal karyotypes. All six MM patients with aneuploidy were in a group of 10 patients in an accelerated or relapse phase of their disease and four had high serum paraprotein levels (7.92, 6.24, 6.80, and 4.24 g/dl, respectively) when their abnormal karyotypes were detected. Five of the 6 MM patients with aneuploidy had received prior chemotherapy. Aneuploidy was not observed in 8 stable MM patients. Abnormalities of chromosome 14 were present in all 6 patients, with a 14q+ marker in 5 and loss of No. 14 in 1. A translocation between Nos. 11 and 14 was found in aneuploid cells of 2 patients who had plasma cell leukemia (PCL). However, the break point in the long arm of No. 11 differed in the 2 patients. A gain of Nos. 5, 9, and 11 was seen in 3 patients, a gain of No 1 in 2, and rearrangements of No. 1 in 5 MM patients, including all 4 who had a 14q+ marker chromosome initially. A deletion of chromosome 6 at band q25 was detected in 2 MM patients and a pericentric inversion of No. 6 (6p21 to 6q13) was seen in the patient with PCL. Three of 4 MM patients had a nonrandom loss of one chromosome 8. Two other MM patients, who were treated with melphalan and prednisone, developed acute nonlymphocytic leukemia (ANLL) 2+ and 4+ years after the diagnosis of MM. Marrow cells of one patient showed a 5q- chromosome and a constitutional translocation involving Nos. 13 and 14 during the preleukemic stage; during the leukemic phase, the karyotype evolved to 50 chromosomes including extra chromosomes 1, 6, 8, 10, and 21 and a missing 7, in addition to the originally detected 5q- and the 13/14 translocation. The peripheral blood from the other patient was hypodiploid, with a missing chromosome 7 and a translocation between 3q and 9p. These patterns of chromosome change resemble those of ANLL rather than MM and are similar to the changes seen in ANLL after treated malignant lymphoma.
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Dau H, Andrews JC, Roelofs TA, Latimer MJ, Liang W, Yachandra VK, Sauer K, Klein MP. Structural consequences of ammonia binding to the manganese center of the photosynthetic oxygen-evolving complex: an X-ray absorption spectroscopy study of isotropic and oriented photosystem II particles. Biochemistry 1995; 34:5274-87. [PMID: 7711049 DOI: 10.1021/bi00015a043] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The structure and orientation of the manganese complex in NH3-treated photosystem II (PS II) membrane particles of spinach are being studied by X-ray absorption spectroscopy. On the basis of earlier work by our group, a structure for the tetranuclear manganese complex of PS II, which consists of two di-mu-oxo-bridged binuclear Mn units linked by a mono-mu-oxo group, has been proposed [Yachandra, V. K., et al. (1993) Science 260, 675-679]. The extended X-ray absorption fine structure (EXAFS) of the complex modified by NH3 binding in the S2-state is suggestive of an increase in the Mn-Mn distance of one of these units from 2.72 +/- 0.02 to 2.87 +/- 0.02 A, whereas the Mn-Mn distance of the second unit seems to be unaffected by NH3 treatment. The elongation of one binuclear center could result from the replacement of one bridging mu-oxo by an amido group. The lengthening of one Mn-Mn distance means that, by NH3 treatment, the distance degeneracy of the 2.7 A Mn-Mn EXAFS interaction is removed. Consequently, the orientation of individual binuclear units with respect to the membrane normal becomes resolvable by EXAFS spectroscopy of partially oriented PS II membrane particles. The angle between the normal of the PS II-containing membrane and the Mn-Mn vector is determined to be 67 degrees +/- 3 degrees for the 2.87 A distance and 55 degrees +/- 4 degrees for the 2.72 A distance. Only small effects on position, shape, and orientation dependence of Mn K-edge spectra result from NH3 treatment, indicating that the Mn oxidation state, the symmetry of the Mn ligand environment, and the orientation of the complex remain essentially unaffected in the annealed NH3 S2-state. Therefore, it seems likely that the angles determined for the ammonia-modified manganese complex are similar to the respective angles of the untreated complex. The structure of the manganese complex and its orientation in the membrane are discussed.
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Ishihara M, Shaklee PN, Yang Z, Liang W, Wei Z, Stack RJ, Holme K. Structural features in heparin which modulate specific biological activities mediated by basic fibroblast growth factor. Glycobiology 1994; 4:451-8. [PMID: 7827407 DOI: 10.1093/glycob/4.4.451] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The biological activity of basic fibroblast growth factor (bFGF) is influenced greatly by direct binding to heparin and heparan sulphate (HS). Heparin-derived oligosaccharides have been utilized to determine the structural requirements present in the polymer that account for binding to bFGF. We had previously demonstrated that fragments > 6 mer can inhibit the interaction between cell surface heparan sulphate proteoglycan (HSPG) and bFGF, and bFGF-induced proliferation of adrenocortical endothelial (ACE) cells. In contrast, oligosaccharides > 10 mer can enhance the binding of bFGF to its high-affinity receptor or support bFGF-induced mitogenesis in ACE cells (Ishihara et al., J. Biol. Chem., 268, 4675-4683, 1993). We have extended these studies to size- and structure-defined oligosaccharides from heparin, 2-O-desulphated (2-O-DS-) heparin, 6-O-desulphated (6-O-DS-) heparin, carboxy-reduced (CR-) heparin and carboxy-amidomethylsulphonated (AMS-) heparin. Oligosaccharides from these polymers were fractionated on a bFGF-affinity column and were assessed as inhibitors or enhancers of specific bFGF-derived biological activities. The results of these studies indicate that both 2-O-sulphate and the negative charge of the carboxy group [L-iduronic acid (IdoA) residues] are required for specific interactions of heparin-derived oligosaccharides with bFGF and for modulation of bFGF mitogenic activity. In addition, the charge of the carboxy groups in uronic acids can be replaced by other functional groups with a negative charge, such as the amidomethyl sulphonate moiety described here.
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Liang W, Ilchenko VS, Savchenkov AA, Matsko AB, Seidel D, Maleki L. Whispering-gallery-mode-resonator-based ultranarrow linewidth external-cavity semiconductor laser. OPTICS LETTERS 2010; 35:2822-2824. [PMID: 20717469 DOI: 10.1364/ol.35.002822] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We demonstrate a miniature self-injection locked distributed-feedback laser using resonant optical feedback from a high-Q crystalline whispering-gallery-mode resonator. The linewidth reduction factor is greater than 10,000, with resultant instantaneous linewidth of less than 200 Hz. The minimal value of the Allan deviation for the laser-frequency stability is 3 x 10(-12) at the integration time of 20 micros. The laser possesses excellent spectral purity and good long-term stability.
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Liang W, Latimer MJ, Dau H, Roelofs TA, Yachandra VK, Sauer K, Klein MP. Correlation between structure and magnetic spin state of the manganese cluster in the oxygen-evolving complex of photosystem II in the S2 state: determination by X-ray absorption spectroscopy. Biochemistry 1994; 33:4923-32. [PMID: 8161553 DOI: 10.1021/bi00182a022] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The structure of the manganese cluster in the S2 state with the g approximately 4 EPR signal (S2-g4 state) generated by 130 K illumination of photosystem II (PSII) membranes prepared from spinach has been investigated by X-ray absorption spectroscopy. The Mn X-ray absorption K-edge spectra of the S2-g4 state not only show a shift of the inflection point to higher energy from the S1 state but also reveal a different edge shape from that of the S2 state with the multiline signal (S2-MLS state). Extended X-ray absorption fine structure (EXAFS) studies of the Mn K-edge show that the structure of the Mn cluster in the S2-g4 state is distinctly different from those in the S2-MLS or S1 states. In the S2-g4 state, the second shell of back-scatters from the Mn absorber is found to contain two Mn-Mn distances of 2.73 and 2.85 A. We interpret this to indicate the presence of two nonequivalent di-mu-oxo-bridged Mn binuclear structures in the Mn cluster of the S2-g4 state. The third shell of the S2-g4 state at about 3.3 A also contains increased heterogeneity. By contrast, very little distance disorder was found to exist in the second shell of the S1 or S2-MLS states. A mechanism is proposed to explain these results in the context of our model for the Mn cluster and the EPR properties of the Mn complex in the S2 state.
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Matsko AB, Savchenkov AA, Liang W, Ilchenko VS, Seidel D, Maleki L. Mode-locked Kerr frequency combs. OPTICS LETTERS 2011; 36:2845-2847. [PMID: 21808332 DOI: 10.1364/ol.36.002845] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We analyze a mode-locked regime in Kerr frequency combs generated in nonlinear microresonators. Using damped driven nonlinear Schrödinger equations we show that the combs can produce subpicosecond optical pulses when the resonators are characterized with a small enough anomalous group velocity dispersion. We provide an analytical solution of the problem for the case of small damping.
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Qian X, Wang B, Zhu ZQ, Sun HX, Ren F, Mu P, Ma C, Liang WD, Li A. Novel N-rich porous organic polymers with extremely high uptake for capture and reversible storage of volatile iodine. JOURNAL OF HAZARDOUS MATERIALS 2017; 338:224-232. [PMID: 28570876 DOI: 10.1016/j.jhazmat.2017.05.041] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/20/2017] [Accepted: 05/22/2017] [Indexed: 06/07/2023]
Abstract
The imino group-contained porous organic polytriphenylamine, which originated from diphenylamine and 1,3,5-tris(4-bromophenyl)benzene, was designedly synthesized though Buchwald-Hartwig coupling reaction. The basic properties including morphologies, structure and thermal stability of the resulting POPs were investigated by scanning electron microscope(SEM), thermo gravimeter analysis (TGA), 13C CP/MAS solid state NMR and Fourier transform infrared spectroscope (FTIR). The pore size distribution of POPs present uniform mesoporous of sizes less than 50nm. Scanning electron microscope images show that the resulting POPs formed as an aggregation composed of nanospheres. The POPs were employed as a physicochemical stable porous medium for removal of radioactive iodine and an iodine uptake of up to 382wt% was obtained. To our knowledge, this is one of the highest adsorption value reported to date. Based on these findings, the resulting POPs shows great potential in the removal of radioactive iodine at different states, through a green, environmentally friendly, and sustainable way.
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Carraro F, Velásquez-Hernández MDJ, Astria E, Liang W, Twight L, Parise C, Ge M, Huang Z, Ricco R, Zou X, Villanova L, Kappe CO, Doonan C, Falcaro P. Phase dependent encapsulation and release profile of ZIF-based biocomposites. Chem Sci 2020; 11:3397-3404. [PMID: 34777742 PMCID: PMC8529536 DOI: 10.1039/c9sc05433b] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 02/13/2020] [Indexed: 11/29/2022] Open
Abstract
Biocomposites composed of Zeolitic Imidazolate Frameworks (ZIFs) are generating significant interest due to their facile synthesis, and capacity to protect proteins from harsh environments. Here we systematically varied the composition (i.e. relative amounts of ligand (2-methylimidazole), metal precursor (Zn(OAc)2·2H2O), and protein) and post synthetic treatments (i.e. washes with water or water/ethanol) to prepare a series of protein@ZIF biocomposites. These data were used to construct two ternary phase diagrams that showed the synthesis conditions employed gave rise to five different phases including, for the first time, biocomposites based on ZIF-CO3-1. We examined the influence of the different phases on two properties relevant to drug delivery applications: encapsulation efficiency and release profile. The encapsulation efficiencies of bovine serum albumin and insulin were phase dependent and ranged from 75% to 100%. In addition, release profiles showed that 100% protein release varied between 40 and 300 minutes depending on the phase. This study provides a detailed compositional map for the targeted preparation of ZIF-based biocomposites of specific phases and a tool for the straightforward analysis of the crystalline phases of ZIF based materials (web application named "ZIF phase analysis"). These data will facilitate the progress of ZIF bio-composites in the fields of biomedicine and biotechnology.
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Sun H, La P, Yang R, Zhu Z, Liang W, Yang B, Li A, Deng W. Innovative nanoporous carbons with ultrahigh uptakes for capture and reversible storage of CO 2 and volatile iodine. JOURNAL OF HAZARDOUS MATERIALS 2017; 321:210-217. [PMID: 27619967 DOI: 10.1016/j.jhazmat.2016.09.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 08/22/2016] [Accepted: 09/05/2016] [Indexed: 06/06/2023]
Abstract
Porous carbons as solid-state adsorbents have recently attracted considerable interest in the areas of storage and capture of CO2 as well as the adsorption of radioactive matters. In this work, cigarette butts, one kind of common wastes referring to the filters, were utilized to prepare highly porous carbons by KOH activation in argon atmosphere. The resulting porous carbon shows a high specific surface area of up to 2751m2g-1 with abundant micropores. The resulting porous carbon exhibits excellent iodine uptake of 262wt% and high CO2 adsorption capacity of 6.0mmolg-1 at ambient pressure and 273K, which both are among the highest values reported to date. Given these excellent iodine uptake, CO2 adsorption capacity, ease of preparation as well as good physiochemical stability, the porous carbons derived from cigarette butts show great potential in the reversible adsorption of radioactive iodine and CO2.
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Liang W, Tadros T, Luckham P. Rheological studies on concentrated polystyrene latex sterically stabilized by poly(ethylene oxide) chains. J Colloid Interface Sci 1992. [DOI: 10.1016/0021-9797(92)90304-5] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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He J, Zhang Z, Xiao C, Liu F, Sun H, Zhu Z, Liang W, Li A. High-Performance Salt-Rejecting and Cost-Effective Superhydrophilic Porous Monolithic Polymer Foam for Solar Steam Generation. ACS APPLIED MATERIALS & INTERFACES 2020; 12:16308-16318. [PMID: 32174098 DOI: 10.1021/acsami.9b22832] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Direct solar desalination with excellent solar photothermal efficiency, lower cost, and extended generator device lifetime is beneficial to increase potable water supplies. To address fundamental challenges in direct solar desalination, herein, we present a new and facile method for the scalable fabrication of the polymer porous foam (VMP) as salt-resistant photothermal materials, which was synthesized through a one-step hydrothermal method using styrene and 1-vinyl-3-ethylimidazolium tetrafluoroborate as monomers and N,N'-methylenebisacrylamide as the cross-linking agent. The as-resulted VMP shows excellent mechanical properties which could have a compression strain of 30%, resulting in its superior processability for practical operation. In addition, by taking advantage of its inherent low density, well-controlled porous structure (porosity is 73.81%), and extremely low thermal conductivity (0.03204 W m-1 K-1), the VMP exhibits an excellent solar evaporation property, and the solar photothermal efficiency can reach more than 88% under 1 kW m-2 irradiation. Moreover, the introduction of ionic liquid moiety (imidazolium tetrafluoroborate) into VMP results in its interesting superhydrophilic wettability, which can accelerate water transportation (wetting in 5s) and resolve the crystalline salt within 1.13 h. In addition, the interconnected macropores of the VMP, as water channels, can replenish the vaporized brine on the surface to prevent salt from adhering. The VMP shows a salt-resistant performance, for example, its solar evaporation efficiency remains nearly unchanged after 6 h duration under 1 sun irradiation. Based on its simple and cost-effective manufacturing process, excellent solar photothermal efficiency, and salt resistance, our VMP may be a promising candidate as photothermal materials for practical desalination from seawater and other wastewater.
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Liang W, Savchenkov AA, Matsko AB, Ilchenko VS, Seidel D, Maleki L. Generation of near-infrared frequency combs from a MgF₂ whispering gallery mode resonator. OPTICS LETTERS 2011; 36:2290-2292. [PMID: 21685996 DOI: 10.1364/ol.36.002290] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report on generation of a 20 nm wide, 35 GHz repetition rate optical frequency comb in a magnesium fluoride whispering gallery mode resonator pumped with 2 mW of 1543 nm light. The high efficiency of comb generation is associated with the small anomalous group velocity dispersion of the resonator. Growth dynamics of the comb is studied and compared with earlier theoretical predictions.
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