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41.
Background
The tryptophan catabolizing enzyme, indoleamine 2,3, dioxygenase (IDO) is one of two mammalian enzymes, which can catabolize the rarest essential amino acid, tryptophan. IDO is inducible by cytokines such as interferon-γ and plays a role in inflammation and maternal tolerance of fetal allografts, although its exact mode of action is unclear. Therefore, we investigated the circumstances under which IDO is expressed in vitro together with the effects of overexpression of IDO on the growth and morphology of cells. 相似文献42.
Within a mean-field approach and using the Glauber-type stochastic dynamics, we study the kinetics of the spin-2 Blume-Capel
model in the presence of a time-varying (sinusoidal) magnetic field. We investigate the time dependence of the average order
parameter and the behavior of the average order parameter in a period, which is also called the dynamic order parameter, as
a function of the reduced temperature. The nature (continuous and discontinuous) of the transition is characterized by the
dynamic order parameter. The dynamic phase transition points are obtained and the phase diagrams are presented in the reduced
magnetic field amplitude and reduced temperature plane. The phase diagrams exhibit one dynamic tricritical point; besides
a disordered and an ordered phases, there are three phase coexistence regions that are strongly dependent on the interaction
parameter.
The text was submitted by the authors in English. 相似文献
43.
44.
X. Huang S. S. Keskin G. Gullu I. Olmez 《Journal of Radioanalytical and Nuclear Chemistry》2001,247(2):317-323
Wet deposition samples from two locations in the Adirondack region of New York were analyzed for trace elemental composition by instrumental neutron activation analysis. Annual fluxes of the measured species were determined by precipitation-weighted and linear-regression methods. Despite several episodes of high deposition fluxes, the cumulative areal wet deposition of trace elements increased fairly linearly (r
2 > 0.9) over the two year sampling period at both sites. This implies that short duration sampling programs may be used to estimate long-term fluxes and cumulative wet deposition impacts. Based on the magnitude of their fluxes, the measured species have been divided into four groups: acidic anions, electroneutral balancing cations, and minor and trace elements of anthropogenic origin. 相似文献
45.
Temel Öztürk Mehmet Nuri Atalar Melahat Göktaş Baki Hazer 《Journal of polymer science. Part A, Polymer chemistry》2013,51(12):2651-2659
One‐step synthesis of block‐graft copolymers by reversible addition‐fragmentation chain transfer (RAFT) and ring‐opening polymerization (ROP) by using a novel initiator was reported. Block‐graft copolymers were synthesized in one‐step by simultaneous RAFT polymerization of n‐butylmethacrylate (nBMA) and ROP of ε‐caprolacton (CL) in the presence of a novel macroinitiator (RAFT‐ROP agent). For this purpose, first epichlorohydrin (EPCH) was polymerized by using H2SO4 via cationic ring‐opening mechanism. And then a novel RAFT‐ROP agent was synthesized by the reaction of potassium ethyl xanthogenate and polyepichlorohydrin (poly‐EPCH). By using the RAFT‐ROP agent, poly[CL‐b‐EPCH‐b‐CL‐(g‐nBMA)] block‐graft copolymers were synthesized. The principal parameters such as monomer concentration, initiator concentration, and polymerization time that affect the one‐step polymerization reaction were evaluated. The block lengths of the block‐graft copolymers were calculated by using 1H‐nuclear magnetic resonance (1H NMR) spectrum. The block length could be adjusted by varying the monomer and initiator concentrations. The characterization of the products was achieved using 1H NMR, Fourier‐transform infrared spectroscopy, gel‐permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, elemental analysis, and fractional precipitation (γ) techniques. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2651–2659 相似文献
46.
47.
This study reports the development of a novel sensing material that reports on analyte concentrations via diffraction of visible
light from polymerized crystalline colloidal arrays (PCCA). The PCCA contains periodic crystalline colloidal array (CCA) of spherical polystyrene colloids. This new method permanently locks the order of the CCA by embedding the CCA into a polymer
network. These materials are mostly used in the development of novel materials which are basically called sensors for metal
ions and all kinds of organic molecules. The polymer around the crystalline colloid can be functionalized with some recognition
molecule, making these materials useful as optical sensors. We developed a sensor, utilizing crown ether, 2-aminomethyl-18-crown-6
(2A18C6) as the recognition agent, that detects K+ in the concentration range from 5 to 160 ppm. 相似文献
48.
In this study, we present the synthesis of poly-MMA macroperoxy initiators obtained by the ATRP of MMA with bromo methyl benzyl t-butyl peroxy ester (t-BuBP) as an initiator, and CuX (X:Br or Cl)/2,2′-bipyridine (bpy) as a catalyst system at 0, 20, 30 and 40°C. The peroxygen groups do not decompose during the ATRP reaction, because low reaction temperatures used for the ATRP reaction are not enough to decompose them. The peroxygen groups of poly-PMMA macroperoxy initiators can lead them to react with a monomer by using appropriate reaction conditions to obtain the block or graft copolymers. For this purpose, poly-MMA macroperoxy initiators were used to synthesize poly(MMA-b-S) block copolymers with S and used for graft copolymerization of polybutadiene (PBd) and natural rubber (RSS-3) to obtain crosslinked poly(MMA-g-PBd) and poly(MMA-g-RSS-3) graft copolymers. Swelling ratio values of the crosslinked graft copolymers in CHCl3 were calculated. The characterizations of the polymers were achieved by FT-IR, 1H-NMR, GPC, DSC, SEM, and the fractional precipitation (γ) techniques. The reaction schemes were also performed using the HYPERCHEM 7.5 program. The mechanical properties of the products were investigated. 相似文献
49.
Baki Ünal 《Entropy (Basel, Switzerland)》2022,24(8)
In this study, causalities of COVID-19 across a group of seventy countries are analyzed with effective transfer entropy. To reveal the causalities, a weighted directed network is constructed. In this network, the weights of the links reveal the strength of the causality which is obtained by calculating effective transfer entropies. Transfer entropy has some advantages over other causality evaluation methods. Firstly, transfer entropy can quantify the strength of the causality and secondly it can detect nonlinear causal relationships. After the construction of the causality network, it is analyzed with well-known network analysis methods such as eigenvector centrality, PageRank, and community detection. Eigenvector centrality and PageRank metrics reveal the importance and the centrality of each node country in the network. In community detection, node countries in the network are divided into groups such that countries in each group are much more densely connected. 相似文献
50.
For an n-simplex in H
n
or S
n
, we give sine theorems and their results for kth-order vertex angles which are defined in this paper. The Gram and edge matrices, and polar simplex of n-simplex in H
n
or S
n
are used to prove the theorems and their results. 相似文献