We report a search for diphoton events with large missing transverse energy produced in pp collisions at √s=1.96 TeV. The data were collected with the D0 detector at the Fermilab Tevatron Collider and correspond to 6.
View Article and Find Full Text PDFAmerican ginseng (Panax quinquefolius) is one of the most commonly used herbal medicines in the world. Discriminating between P. quinquefolius grown in different countries is difficult using traditional quantitation methods.
View Article and Find Full Text PDFThe concentrations of hexabromocyclododecanes (HBCD) in Sargassum fusiforme, the common Chinese edible seaweed, were investigated by LC-MS/MS. For the recovery of HBCD, the efficiency levels of ultrasonic-assisted extraction, microwave-assisted extraction, Soxhlet extraction and pressurised liquid extraction were compared under different conditions. Pressurised liquid extraction and ultrasonic-assisted extraction resulted in complete extraction of HBCD (92.
View Article and Find Full Text PDFInternal alkynes undergo 1,1-carboboration reactions upon treatment with boranes RB(C(6)F(5))(2) (R = C(6)F(5), CH(3)) to yield trisubstituted alkenylboranes. These products can be used as substrates in Pd-catalyzed cross-coupling reactions.
View Article and Find Full Text PDFGlioblastoma multiforme (GBM) has an abysmal prognosis. We now know that the epidermal growth factor receptor (EGFR) signaling pathway and the loss of function of the tumor suppressor genes p16Ink4a/p19ARF and PTEN play a crucial role in GBM pathogenesis: initiating the early stages of tumor development, sustaining tumor growth, promoting infiltration, and mediating resistance to therapy. We have recently shown that this genetic combination is sufficient to promote the development of GBM in adult mice.
View Article and Find Full Text PDFIntersubgenomic heterosis in rapeseed has been revealed in previous studies by using traditional Brassica napus (A(n)A(n)C(n)C(n)) to cross partial new type B. napus with A(r)/C(c) introgression from the genomes of B. rapa and B.
View Article and Find Full Text PDFPurpose: Routine ultrasound screening to predict gestational age is important for risk assessment of pregnancy complications among pregnant women. We explored a quantitative method for sonographic analysis of placental texture, with the objective of reproducible measurement.
Methods: We studied 151 pregnant women; the gestational ages of their fetuses ranged from 10 to 38 weeks.
This paper presents some unusual reactions of lanthanide tris(alkyl)s or lanthanide mono-Cp' (Cp' = (C(5)Me(4))SiMe(3)) bis(alkyl)s with pyrrolyl ligands, and the eta(5)- or eta(1)-coordination mode of the pyrrolyl ring, as well as C=N and C=O double bonds insertion into Ln-sigma-C moities. N,N,O-tridentate ligand HL(1), 2-(2-CH(3)OC(6)H(3)N=CH)-C(4)H(3)NH, was prepared. Treatment of HL(1) with rare-earth metal tris(alkyl)s, Ln(CH(2)SiMe(3))(3)(THF)(2), generated centrosymmetric bimetallic (pyrrolylaldiminato)lanthanide mono(alkyl) complexes [{2-(2-CH(3)OC(6)H(3)NC(H)R)-C(4)H(3)N}LnR](2) (1a: Ln = Y; 1b: Ln = Lu) (R = CH(2)SiMe(3)).
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
June 2010
NIR spectroscopy technique was attempted to measure total flavone content in snow lotus in this work. Interval partial least square with genetic algorithm (iPLS-GA) was used to select the efficient spectral regions and variables in model calibration. The performance of the final model was back-evaluated according to root mean square error of calibration (RMSEC) and correlation coefficient (R(c)) in calibration set, and tested by mean square error of prediction (RMSEP) and correlation coefficient (R(p)) in prediction set.
View Article and Find Full Text PDFThe effects of 80% ethanolic chlorella extracts (GPE) on carbon tetrachloride (CCl(4))-induced hepatic damage were investigated in Sprague-Dawley rats. The rats were orally treated with GPE (0.5 g/kg body weight) or silymarin (0.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
February 2009
Interest in the interaction between cationic porphyrins, particularly derivatives of meso-tetra(N-methylpyridinium-4-yl) porphyrin(TMPyP), and DNA abounds because they are versatile DNA-binding agents that could find application in photodynamic therapy, cancer detection, artificial nucleases, virus inhibition and so on. The interaction of two water-soluble cationic porphyrins, meso-tetrakis(4-N, N, N-trimethylanilinium) porphyrin (TMAP) and 5-phenyl-10,15,20-tris[4-(N-methyl) pyridinium]porphyrin (TriMPyP), with calf thymus DNA (ctDNA) was studied by UV-Vis absorption spectroscopy, fluorescence spectroscopy and resonance light scattering technique. TriMPyP forms aggregate in water due to the molecular asymmetry while TMAP exists as monomers.
View Article and Find Full Text PDFWe present detailed investigations of our previously reported observations of the 3(1)Delta(g) and 4(1)Delta(g) Rydberg states having separated-atom limits of Na(3s) + Na(4d) and Na(3s) + Na(4f), respectively, of Na(2) using high-resolution cw optical-optical double resonance spectroscopic measurements and analyzing the assigned rovibrational energy levels both by the individual linear fit method and the Dunham polynomial fit method. We have sorted out e/f-parity observed energy levels, and then from the Dunham polynomial fits of the e-parity levels, we have derived molecular constants and constructed Rydberg-Klein-Rees potentials of the 3(1)Delta(g) and 4(1)Delta(g) states, which appear to be twin states with an avoided crossing at R(c) = 4.10 A and a splitting of DeltaE(c) = 94 cm(-1).
View Article and Find Full Text PDF3D-IPS/DFFT is an extension of the three-dimensional isotropic periodic sum (3D-IPS) for evaluation of electrostatic and Lennard-Jones interactions in heterogeneous systems; it utilizes a discrete fast Fourier transform (DFFT) for efficient calculation of the IPS potential with a large local region radius. The method is demonstrated to be highly accurate for simple bulk fluids, liquid/liquid and liquid/vapor interfaces, and lipid bilayers and monolayers. Values for r(C) (the cutoff distance for direct evaluation of pairs) and R(C) (the local region radius) equal to 10 A and twice the longest edge of the periodic cell, respectively, provide excellent efficiency and accuracy.
View Article and Find Full Text PDFIn March of 2008, a leaf scab disease was observed in a papaya (Carica papaya L.) orchard at Guoshing, 24.03°N, 120.
View Article and Find Full Text PDFBackground: Most women with a clinical presentation consistent with ovarian cancer have benign conditions. Therefore methods to distinguish women with ovarian cancer from those with benign conditions would be beneficial. We describe the development and preliminary evaluation of a serum-based multivariate assay for ovarian cancer.
View Article and Find Full Text PDFHIV protease inhibitors are a key component of anti-retroviral therapy, but their susceptibility to cytochrome P(450) metabolism reduces their systemic availability and necessitates repetitive dosing. Importantly, failure to maintain adequate inhibitor levels is believed to provide an opportunity for resistance to emerge; thus, new strategies to prolong the lifetime of these drugs are needed. Toward this goal, numerous prodrug approaches have been developed, but these methods involve creating inactive precursors that require enzymatic processing.
View Article and Find Full Text PDFArsenic has been linked to increased prevalence of cancer and cardiovascular disease (CVD), but the long-term impact of arsenic exposure remains unclear. Human paraoxonase (PON1) is a high-density lipoprotein-associated antioxidant enzyme which hydrolyzes oxidized lipids and is thought to be protective against atherosclerosis, but evidence remains limited to case-control studies. Only recently have genes encoding enzymes responsible for arsenic metabolism, such as AS3MT and GSTO, been cloned and characterized.
View Article and Find Full Text PDFSensors (Basel)
September 2012
Ion-sensitive, field-effect transistors (ISFET) have been useful biosensors in many applications. However, the signal-to-noise ratio of the ISFET is limited by its intrinsic, low-frequency noise. This paper presents an ISFET capable of utilizing lateral-bipolar conduction to reduce low-frequency noise.
View Article and Find Full Text PDFMol Biol Rep
November 2009
Relative quantification real-time PCR has become a routine method in molecular biology research to study the small amount gene expression. There are a few mathematical models for relative quantification data analysis in real-time PCR, and the formula 2(-DDCT ) is one of the most frequently used method. In this paper, we are to present another equation which directly calculates the change rate (R (c)) of gene expression, and give a example to compare the application of this model with 2(-DDCT).
View Article and Find Full Text PDFThe electronic structures of the molecules ((t)BuO)(3)M[triple bond]N (M = Cr, Mo, W) have been investigated with gas phase photoelectron spectroscopy and density functional calculations. It is found that the alkoxide orbitals mix strongly with the M[triple bond]N triple bond orbitals and contribute substantially to the valence electronic structure. The first ionization of ((t)BuO)(3)Cr[triple bond]N is from an orbital of a(2)(C(3v)) symmetry that is oxygen based and contains no metal or nitrogen character by symmetry.
View Article and Find Full Text PDFA comprehensive study has been made to predict the adsorption structures and (31)P NMR chemical shifts of various trialkylphosphine oxides (R3PO) probe molecules, viz., trimethylphosphine oxide (TMPO), triethylphosphine oxide (TEPO), tributylphosphine oxide (TBPO), and trioctylphosphine oxide (TOPO), by density functional theory (DFT) calculations based on 8T zeolite cluster models with varied Si-H bond lengths. A linear correlation between the (31)P chemical shifts and proton affinity (PA) was observed for each of the homologous R3PO probe molecules examined.
View Article and Find Full Text PDFWe studied the 1(2)A' '(X2A' '), 1(2)A' (A2A'), 2(2)A' ' (B2A' '), and 2(2)A' (C2A') states of the C2H3Cl+ ion using the complete active space self-consistent field (CASSCF) and multiconfiguration second-order perturbation theory (CASPT2) methods. For the four ionic states, we calculated the equilibrium geometries, adiabatic (T0) and vertical (Tv) excitation energies, and relative energies (Tv') at the geometry of the molecule at the CASPT2 level and the Cl-loss dissociation potential energy curves (PECs) at the CASPT2//CASSCF level. The computed oscillator strength f value for the X2A' ' <-- A2A' transition is very small, which is in line with the experimental fact that the A state has a long lifetime.
View Article and Find Full Text PDFWe use the concept of the Filippov solution to study the dynamics of a class of delayed dynamical systems with discontinuous right-hand side, which contains the widely studied delayed neural network models with almost periodic self-inhibitions, interconnection weights, and external inputs. We prove that diagonal-dominant conditions can guarantee the existence and uniqueness of an almost periodic solution, as well as its global exponential stability. As special cases, we derive a series of results on the dynamics of delayed dynamical systems with discontinuous activations and periodic coefficients or constant coefficients, respectively.
View Article and Find Full Text PDFGenetic variants of the neuronal sortilin-related receptor (SORL1) have been demonstrated to modulate the risk of Alzheimer's disease (AD) in different American and European populations [Rogaeva, E., Meng, Y., Lee, J.
View Article and Find Full Text PDFPhys Rev Lett
September 2007
We report measurements of branching fractions for B --> K pi and B --> pi pi decays based on a data sample of 449 x 10(6) BB[over] pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We also measure the ratios of partial widths for B-->Kpi decays, namely R(c) identical with 2Gamma(B(+) --> K(+) pi(0))/Gamma(B(+) --> K(0) pi(+)) = 1.08+/-0.
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