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101.
Protein microarray technology is a powerful, popular tool for the high-throughput analysis of protein interactions. One important use for protein microarray technology is protein quantification by immunoassay, which was originally based on enzyme linked immunosorbent assay (ELISA) methods. Recently, new research and diagnostic applications have created a need for a rapid and easily applied high-throughput protein quantification method. Here, we introduce several novel techniques that address these needs. Our improved protein microarray-based sandwich immunoassay techniques allow researchers to: (1) control the size and shape of protein spots on the microarray using a perforated seal; (2) analyze two proteins within a single spot, thus increasing the number of tests run on a single microarray without increasing the number of protein spots; (3) improve the efficiency and speed of the Ag-Ab interaction through vibratory reagent convection, which increased the signal intensity by more than two-fold and decreased the reaction time from 30 to 10 min. These new techniques will facilitate rapid immunoassays for diagnostic purposes and other research areas utilizing protein microarray analysis, such as investigations of ligand-receptor or protein-small molecule interactions. 相似文献
102.
Ismail AH Bassil BS Yassin GH Keita B Kortz U 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(20):6163-6166
Wheely: For the first time and very unexpectedly, a rupture of the very stable {P(8)W(48)} wheel was observed in aqueous solution at pH?4 and 80?°C in the presence of Fe(III), Eu(III)/Gd(III), and H(2)O(2). This inorganic ring opening is unprecedented in polyoxometalate chemistry. 相似文献
103.
SK Podiyanachari R Fröhlich CG Daniliuc JL Petersen G Kehr G Erker N Suzuki S Yuasa K Hagimori S Inoue T Asada T Takemoto Y Masuyama 《Dalton transactions (Cambridge, England : 2003)》2012,41(35):10811-10816
The reaction of η(2)-iminozirconocene chloride complexes with trimethylsilylethynyl lithium leads to rapid C-C coupling at room temperature to yield the corresponding five-membered aza-zirconacycloallenoids. Such compounds were also obtained by trapping of in situ generated zirconocene with alkynyl imines. 相似文献
104.
T Shirahata K Shiratori S Kumeta T Kawamoto T Ishikawa SY Koshihara Y Nakano H Yamochi Y Misaki T Mori 《Journal of the American Chemical Society》2012,134(32):13330-13340
A series of quasi-one-dimensional molecular conductors (DMEDO-TTF)(2)XF(6) (X = P, As, and Sb), where DMEDO-TTF is dimethyl(ethylenedioxy)tetrathiafulvalene, undergo characteristic structural transitions in the range of 130-195 K for the PF(6) salt and 222-242 K for the AsF(6) salt. The dramatic structural transition is induced by the order of the ethylenedioxy moiety, and the resulting anion rotation leads to the reconstruction of the H···F interaction between the methyl groups and the anions. The unique hydrogen bonds play a crucial role in the transition. As a result, the molecular packing is rearranged entirely; the high-temperature molecular stacks with an ordinary quasi-triangular molecular network transforms to a quasi-square-like network, which has never been observed among organic conductors. Nonetheless, the low-temperature phase exhibits a good metallic conductivity as well, so the transition is a metal-metal (MM) transition. The resistivity measured along the perpendicular direction to the conducting ac-plane (ρ(⊥)) and the calculation of the Fermi surface demonstrate that the high-temperature metal phase is a one-dimensional metal, whereas the low-temperature metal phase has considerable interchain interaction. In the SbF(6) salt, a similar structural transition takes place around 370 K, so that the quasi-square-like lattice is realized even at room temperature. Despite the largely different MM transition temperatures, all these salts undergo metal-insulator (MI) transitions approximately at the same temperature of 50 K. The low-temperature insulator phase is nonmagnetic, and the reflectance spectra suggest the presence of charge disproportionation with small charge difference (0.14). 相似文献
105.
Yasuko Saito Toshiyuki Takano Keita Sakakibara Hiroshi Kamitakahara Fumiaki Nakatsubo 《Cellulose (London, England)》2012,19(6):2105-2114
2,3-Di-O-myristyl-6-O-(zinc(II) phthalocyaninyl) cellulose (5) was synthesized from cellulose (1) by five reaction steps via 6-O-(3′,4′-dicyanophenyl)-2,3-di-O-myristyl cellulose (4). The key reaction was phthalocyanine-ring formation on a cellulose backbone, that is, the reaction of compound 4 with o-phthalodinitrile in the presence of hexamethyldisilazane and zinc acetate in DMF afforded to compound 5 in 35.4 % yield. Consequently, the degree of substitution with phthalocyanine moieties of compound 5 was 0.38. The LB monolayer film of compound 5 on an indium tin oxide (ITO) electrode was found to show photocurrent generation performance at 680 nm. 相似文献
106.
Subramanian S Devasahayam N McMillan A Matsumoto S Munasinghe JP Saito K Mitchell JB Chandramouli GV Krishna MC 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2012,214(1):244-251
Oxygen maps derived from electron paramagnetic resonance spectral-spatial imaging (EPRI) are based upon the relaxivity of molecular oxygen with paramagnetic spin probes. This technique can be combined with MRI to facilitate mapping of pO(2) values in specific anatomic locations with high precision. The co-registration procedure, which matches the physical and digital dimensions of EPR and MR images, may present the pO(2) map at the higher MRI resolution, exaggerating the spatial resolution of oxygen, making it difficult to precisely distinguish hypoxic regions from normoxic regions. The latter distinction is critical in monitoring the treatment of cancer by radiation and chemotherapy, since it is well-established that hypoxic regions are three or four times more resistant to treatment compared to normoxic regions. The aim of this article is to describe pO(2) maps based on the intrinsic resolution of EPRI. A spectral parameter that affects the intrinsic spatial resolution of EPRI is the full width at half maximum (FWHM) height of the gradient-free EPR absorption line in frequency-encoded imaging. In single point imaging too, the transverse relaxation times (T(2)(?)) limit the resolution since the signal decays by exp(-t(p)/T(2)(?)) where the delay time after excitation pulse, t(p), is related to the resolution. Although the spin densities of two point objects may be resolved at this separation, it is inadequate to evaluate quantitative changes of pO(2) levels since the linewidths are proportionately affected by pO(2). A spatial separation of at least twice this resolution is necessary to correctly identify a change in pO(2) level. In addition, the pO(2) values are blurred by uncertainties arising from spectral dimensions. Blurring due to noise and low resolution modulates the pO(2) levels at the boundaries of hypoxic and normoxic regions resulting in higher apparent pO(2) levels in hypoxic regions. Therefore, specification of intrinsic resolution and pO(2) uncertainties are necessary to interpret digitally processed pO(2) illustrations. 相似文献
107.
Sakakibara K Nakatsubo F French AD Rosenau T 《Chemical communications (Cambridge, England)》2012,48(62):7672-7674
Right-handedness derived from bisporphyrins attached to a cellotriose backbone at O-6 and O'-6 positions is revealed for the first time. This cellotriose is proposed as a model of alternatingly functionalized cellulosics, which have promising properties for applications in optoelectronics and molecular receptors owing to the chirality and rigid backbone effects. 相似文献
108.
Keita Sakakibara Yasuhiro Ogawa Fumiaki Nakatsubo 《Macromolecular rapid communications》2007,28(11):1270-1275
Langmuir‐Blodgett films of a cellulose derivative containing porphyrins, porphyrin‐cellulose, were fabricated in order to construct a cellulose‐based molecular photocurrent generation system. On visible light illumination of the LB monolayer film deposited on an ITO electrode, anodic photocurrents were observed with a quantum yield of 1.6% at an applied potential of 0 V versus SCE, and 3.8–4.6% at 0.2–0.3 V versus SCE. These values indicate that the self‐quenching of the photoexcited porphyrins in the cellulose LB film was suppressed, while porphyrin moieties in the LB film had a densely packed structure. This is because the porphyrins are located at a distance of approximately 1.0 nm along the cellulose backbone.
109.
Yasunori Fujikoshi Takashi Kanda Megu Ohtaki 《Annals of the Institute of Statistical Mathematics》1999,51(4):707-721
This paper deals with some inferential problems under an extended growth curve model with several hierarchical within-individuals design matrices. The model includes the one whose mean structure consists of polynomial growth curves with different degrees. First we consider the case when the covariance matrix is unknown positive definite. We derive a LR test for examining the hierarchical structure for within individuals design matrices and a model selection criterion. Next we consider the case when a random coefficients covariance structure is assumed, under certain assumption of between-individual design matrices. Similar inferential problems are also considered. The dental measurement data (see, e.g., Potthoff and Roy (1964, Biometrika, 51, 313-326)) is reexamined, based on extended growth curve models. 相似文献
110.
Jun Koyanagi Keita Takeguchi Kazuki Murai Hirokazu Furue Nobuyuki Masuda 《Molecular Crystals and Liquid Crystals》2017,656(1):54-65
Blue-phase liquid crystals form three-dimensional structures in a self-organizing manner and are similar to living tissue structures such as the teeth of mice and collagen tissues. This study presents numerical results regarding the conditions under which blue-phase liquid crystals occur. The Monte Carlo simulations are performed by employing an improved Lennard–Jones potential that considers anisotropy and chirality. The conditions for the formation of the blue phase, which vary with respect to the chirality, are examined first. The relationship between the anisotropic parameters and the chiral parameter for the formation of the blue phase is discussed. Identical blue-phase structures are obtained, even when the cell size and molecular number are varied drastically. This discussion is useful for considering the scale-up problem, which is almost always a difficult issue for molecular-scale simulations. 相似文献