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101.
Ayşegül Karaküçük-İyidoğan Zeliha Mercan Emine Elçin Oruç-Emre Demet Taşdemir Derya İşler İbrahim Halil Kılıç 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):661-673
Abstract The synthesis and characterization of 18 novel thiosemicarbazones have been investigated as part of a research program on development of compounds with antibacterial and antioxidant activities. Among the tested compounds, 2-(4-hydroxybenzylidene)-N-[4-(trifluoromethoxy)phenyl]hydrazine carbothioamide (3g) and 2-(thiophen-2-ylmethylidene)-N-[4-(morpholin-4-yl)phenyl]hydrazine carbothioamide (4b) showed excellent inhibition potency at low concentration (0.5 μg/mL) against Gram-positive pathogens (Enterococcus faecalis and Staphylococcus aureus). All tested compounds were also found to possess antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text, tables, and figures.] 相似文献
102.
Gokce E Shuford CM Franck WL Dean RA Muddiman DC 《Journal of the American Society for Mass Spectrometry》2011,22(12):2199-2208
Normalization of spectral counts (SpCs) in label-free shotgun proteomic approaches is important to achieve reliable relative
quantification. Three different SpC normalization methods, total spectral count (TSpC) normalization, normalized spectral
abundance factor (NSAF) normalization, and normalization to selected proteins (NSP) were evaluated based on their ability
to correct for day-to-day variation between gel-based sample preparation and chromatographic performance. Three spectral counting
data sets obtained from the same biological conidia sample of the rice blast fungus Magnaporthe oryzae were analyzed by 1D gel and liquid chromatography-tandem mass spectrometry (GeLC-MS/MS). Equine myoglobin and chicken ovalbumin
were spiked into the protein extracts prior to 1D-SDS- PAGE as internal protein standards for NSP. The correlation between
SpCs of the same proteins across the different data sets was investigated. We report that TSpC normalization and NSAF normalization
yielded almost ideal slopes of unity for normalized SpC versus average normalized SpC plots, while NSP did not afford effective
corrections of the unnormalized data. Furthermore, when utilizing TSpC normalization prior to relative protein quantification,
t-testing and fold-change revealed the cutoff limits for determining real biological change to be a function of the absolute
number of SpCs. For instance, we observed the variance decreased as the number of SpCs increased, which resulted in a higher
propensity for detecting statistically significant, yet artificial, change for highly abundant proteins. Thus, we suggest
applying higher confidence level and lower fold-change cutoffs for proteins with higher SpCs, rather than using a single criterion
for the entire data set. By choosing appropriate cutoff values to maintain a constant false positive rate across different
protein levels (i.e., SpC levels), it is expected this will reduce the overall false negative rate, particularly for proteins
with higher SpCs. 相似文献
103.
Four unsymmetrical vic-dioximes: [L1H2] N-(4-butylphenyl)amino-amphi-glyoxime, [L2H2] N-(4-butylphenyl)amino-anti-glyoxime, [L3H2] N-(4-phenylazophenyl)amino-amphi-glyoxime and [L4H2] N-(4-phenylazophenyl)amino-anti-glyoxime have been prepared from amphi-chloroglyoxime, anti-chloroglyoxime, 4-butylaniline and 4-(phenylazo)aniline respectively. The complexes of these vic-dioximes with NiII, CoII, CuII and CdII ions have been investigated. All are insoluble in common solvents. Their i.r. spectra and elemental analyses are given, together with mass and 1H-n.m.r. spectra of the ligands. 相似文献
104.
Ucar Asuman Findik Mukerrem Kuzu Muslum Pehlivanoglu Suray Sayin Ulku Sayin Zafer Akgemci Emine Guler 《Research on Chemical Intermediates》2021,47(2):533-550
Research on Chemical Intermediates - Metal complexes of thiosemicarbazones have been receiving considerable attention in biological applications such as antimicrobial and anticancer therapies. In... 相似文献
105.
Assessment of the orbital‐optimized coupled‐electron pair theory for thermochemistry and kinetics: Improving on CCSD and CEPA(1) 下载免费PDF全文
An assessment of the orbital‐optimized coupled‐electron pair theory [or simply “optimized CEPA(0),” OCEPA(0)] [Bozkaya and Sherrill, J. Chem. Phys. 2013, 139, 054104] for thermochemistry and kinetics is presented. The OCEPA(0) method is applied to closed‐ and open‐shell reaction energies, barrier heights, and radical stabilization energies (RSEs). The performance of OCEPA(0) is compared with those of the MP2, CEPA(0), OCEPA(0), CEPA(1), coupled‐cluster singles and doubles (CCSD), and CCSD(T) methods [at complete basis set limits employing cc‐pVTZ and cc‐pVQZ basis sets]. For the most of the test sets, the OCEPA(0) method performs better than CEPA(0), CEPA(1), and CCSD, and provides accurate results. Especially, for open‐shell reaction energies and barrier heights, the OCEPA(0)–CEPA(1) and OCEPA(0)–CCSD differences become obvious. Similarly, for barrier heights and RSEs, the OCEPA(0) method improves on CEPA(0) by 1.6 and 2.3 kcal mol?1. Our results demonstrate that the CEPA(0) method dramatically fails when the reference wave function suffers from the spin‐contamination problem. Conversely, the OCEPA(0) method can annihilate spin‐contamination in the unrestricted‐Hartree–Fock initial guess orbitals and can yield stable solutions. For overall evaluation, we conclude that the OCEPA(0) method is quite helpful not only for problematic open‐shell systems and transition‐states but also for closed‐shell molecules. Hence, one may prefer OCEPA(0) over CEPA(0), CEPA(1), and CCSD as an method, where N is the number of basis functions, for thermochemistry and kinetics. As discussed previously, the cost of the OCEPA(0) method is as much as of CCSD and CEPA(1) for energy computations. However, for analytic gradient computations, the OCEPA(0) method is two times less expensive than CCSD and CEPA(1). Further, the stationary properties of the OCEPA(0) method making it promising for excited state properties via linear response theory. © 2014 Wiley Periodicals, Inc. 相似文献
106.
This work is aimed to show that various problems from different fields can be modeled more efficiently using multiplicative
calculus, in place of Newtonian calculus. Since multiplicative calculus is still in its infancy, some effort is put to explain
its basic principles such as exponential arithmetic, multiplicative calculus, and multiplicative differential equations. Examples
from finance, actuarial science, economics, and social sciences are presented with solutions using multiplicative calculus
concepts. Based on the encouraging results obtained it is recommended that further research into this field be vested to exploit
the applicability of multiplicative calculus in different fields as well as the development of multiplicative calculus concepts. 相似文献
107.
The multiplicative version of Adams Bashforth–Moulton algorithms for the numerical solution of multiplicative differential
equations is proposed. Truncation error estimation for these numerical algorithms is discussed. A specific problem is solved
by methods defined in multiplicative sense. The stability properties of these methods are analyzed by using the standart test
equation. 相似文献
108.
Emine Özergin Mehmet Ali Özarslan Abdullah Alt?n 《Journal of Computational and Applied Mathematics》2011,235(16):4601-4610
The main object of this paper is to present generalizations of gamma, beta and hypergeometric functions. Some recurrence relations, transformation formulas, operation formulas and integral representations are obtained for these new generalizations. 相似文献
109.
In this paper, we prove that every metric line of a Möbius gyrovector space ${(\mathbb{R}_{1}^{n}, \oplus, \otimes)}$ is exactly a cogyroline of itself, and also we prove the nonexistence of periodic lines in ${(\mathbb{R}_{1}^{n}, \oplus, \otimes)}$ . 相似文献
110.
Emine Bulut 《Journal of Macromolecular Science: Physics》2014,53(5):902-917
Microspheres of blends of sodium alginate (NaAlg) and sodium carboxymethyl cellulose (NaCMC) were prepared by a water-in-oil (w/o) emulsion crosslinking method and used for the release of donepezil hydrochloride (DP), which is an Alzheimer's drug. The microspheres were characterized with Fourier transform infrared spectroscopy (FTIR), differantial scanning calorimetry (DSC), and scanning electron microscopy (SEM). The microsphere characteristics, including DP entrapment efficiency, particle size, equilibrium swelling degree (ESD), and DP release kinetics, were determined. The effects of the preparation conditions, including the NaAlg/NaCMC (w/w) ratio, drug/polymer (w/w) ratio, cross-linker concentration and time of exposure to the cross-linker, on the release of DP were investigated for successive gastrointestinal tract pH values of 1.2, 6.8, and 7.4 at 37°C. The release of DP increased with the increase in NaAlg/NaCMC (w/w) ratio and drug/polymer (d/p) ratio, while it decreased with increasing extent of cross-linking. The optimum DP release was obtained as 99.13% for a NaAlg/NaCMC (w/w) ratio of 2/1, d/p ratio of 1/4, CaCl2 concentration of 5% and crosslinking time of 30 min. It was also observed from release results that DP release from the microspheres through the external medium was higher at low pH (1.2) values than that at high pH (6.8 and 7.4) values. The DP release of the microspheres followed either Fickian transport below a value of n < 0.5 or anomalous transport (n = 0.5–1.0). 相似文献