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51.
AbstractIn this paper, we study different classes of generalized convex/quasiconvex set-valued maps, defined by means of the l-type and u-type preorder relations, currently used in set-valued optimization. In particular, we identify those classes of set-valued maps for which it is possible to extend the classical characterization of convex real-valued functions by quasiconvexity of their affine perturbations. 相似文献
52.
[structure: see text] Apoptolidin (1) exhibits potent and highly selective apoptosis inducing activity against sensitive cancer cell lines and is hypothesized to act by inhibition of mitochondrial F(0)F(1)-ATP synthase. A series of apoptolidin derivatives, including a new intermolecular Diels-Alder adduct, were analyzed for antiproliferative activity in E1A-transformed rat fibroblasts. Potent F(0)F(1)-ATPase inhibition was not a sufficient determinant of antiproliferative activity for several analogues, suggesting the existence of a secondary biological target or more complex mode of action for apoptolidin. 相似文献
53.
Seto H Yamada NL Nagao M Hishida M Takeda T 《The European physical journal. E, Soft matter》2008,26(1-2):217-223
Membrane fluctuations of dipalmitoylphosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) were investigated by neutron spin echo spectroscopy. The intermediate structure factor was analyzed in terms of the model proposed by Zilman and Granek (Phys. Rev. Lett. 77, 4788 (1996)), and the bending modulus of lipid bilayers was derived. The hardening of a lipid bilayer upon approaching the main transition point in the anomalous swelling regime was observed, which naturally connects the bending modulus in the gel phase below the main transition temperature. 相似文献
54.
Kawaguchi M Ito R Honda H Endo N Okanouchi N Saito K Seto Y Nakazawa H 《Journal of chromatography. A》2008,1206(2):196-199
A simple and highly sensitive method called stir bar sorptive extraction (SBSE) and thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS), which is used for the determination of trace amounts of 5-chloro-2-(2,4-dichlorophenoxy)phenol (triclosan) in river water samples, is described. A stir bar coated with polydimethylsiloxane (PDMS) is added to a 10mL water sample and stirring is carried out for 120min at room temperature (25 degrees C) in a vial. Then, the PDMS stir bar is subjected to TD-GC-MS. The detection limit of triclosan is 5ngL(-1) (ppt). The method shows linearity over the calibration range (0.02-20mugL(-1)) and the correlation coefficient is higher than 0.997 for triclosan standard solution. The recovery of triclosan in river water samples ranges from 91.9 to 108.3% (RSD: 4.0-7.0%). This simple, accurate, sensitive, and selective analytical method may be used in the determination of trace amounts of triclosan in river water samples. 相似文献
55.
Kawaguchi M Ito R Honda H Endo N Okanouchi N Saito K Seto Y Nakazawa H 《Journal of chromatography. A》2008,1200(2):260-263
A method for the simultaneous measurement of benzophenone (BP) sunscreen compounds, its derivatives 2,4-dihydroxybenzophenone (BP-1), 2-hydroxy-4-methoxybenzophenone (BP-3), 2-hydroxy-4-methoxy-4'-methylbenzophenone (BP-10), 2-hydroxybenzophenone (2OH-BP), 3-hydroxybenzophenone (3OH-BP) and 4-hydroxybenzophenone (4OH-BP), in water samples was developed using stir bar sorptive extraction (SBSE) with in situ derivatization followed by thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS). The detection limit is 0.5-2 ng L(-1) (ppt) for the seven BPs. The method shows good linearity and the correlation coefficients are equal to or higher than 0.990 for all the analyte. The average recoveries of BPs range from 102.0 to 128.1% (RSD<15.4%, n=6). Trace amounts of BPs in river water samples were determined by the present method. 相似文献
56.
Negishi M Seto H Hase M Yoshikawa K 《Langmuir : the ACS journal of surfaces and colloids》2008,24(16):8431-8434
The mobility of phospholipid molecules at a water/oil interface on cell-sized phospholipid-coated microdroplets was investigated through the measurement of diffusion constants by fluorescence recovery after photobleaching. It is found that the diffusion constant of phospholipids showed the relation D approximately (eta water + eta oil) -0.85, where D is the diffusion constant, eta water is the viscosity of water, and eta oil is the viscosity of oil. This observation indicates that the viscosity of the surrounding oil is the primary factor that determines the diffusibility of phospholipids at a water/oil interface. 相似文献
57.
A closed subspace is said to be invariant if it is invariant under the Toeplitz operators and . Invariant subspaces of are well-known to be very complicated. So discovering some good examples of invariant subspaces will be beneficial to the general study. This paper studies a type of invariant subspace constructed through a sequence of inner functions. It will be shown that this type of invariant subspace has direct connections with the Jordan operator. Related calculations also give rise to a simple upper bound for , where are zeros of a Blaschke product.
58.
N.L. Yamada H. Endo N. Osaka Y. Kawabata M. Nagao T. Takeda H. Seto M. Shibayama 《Physica B: Condensed Matter》2009,404(17):2607-2610
Expansion of a detection area is an effective method to increase the measurement efficiency of a neutron spin echo (NSE) spectrometer as well as other spectrometers. For this purpose, we installed a new π/2 spin flipper and Fresnel coil of iNSE spectrometer at JRR-3, Tokai, Japan, for wide-area data acquisition. In this study, we propose a data reduction method to correct the phase inhomogeneity due to the path difference of neutrons on the large detection area. This method can convert many NSE signals at small areas to one NSE signal at a large area with taking the phase offset due to the phase inhomogeneity into account. The measurement efficiency increased by approximately one order of magnitude as a result of the detection area expansion. 相似文献
59.
In order to quickly confirm a potentially hazardous psychoactive designer drug (a compound in which part of the molecular structure of a stimulant or narcotic has been modified), we created a psychoactive drugs data library by performing analysis using liquid chromatography with photodiode array spectrophotometry (LC/PDA) and gas chromatography-mass spectrometry (GC/MS). The data in this library consist of the LC capacity factor (k′) ratios in relation to the internal standard, the ultraviolet (UV) spectra and the MS spectra of 104 compounds. By performing a comparative study of the data in this report with the analytical data for commercial and illegal drug products, it is possible to quickly identify the psychoactive designer drugs in 205 purchased products by using the library. Further, it is possible to analogize the structure of drugs for which there is no matching data in the library using similar data.Furthermore, when structural isomers of controlled substances have detected from the presented library, similarity of their biological effects on human will be predicted, thus leading to regulate their public circulation. Examples of these types of isomers include, for instance, the narcotic 3,4,5-trimethoxyamphetamine (TMA) and its positional isomers 2,4,5-trimethoxyamphetamine (TMA-2) and 2,4,6-trimethoxyamphetamine (TMA-6), or the narcotic 1-(3-chlorophenyl)piperazine (3CPP) and its isomers 1-(o-chlorophenyl)piperazine (2CPP) and 1-(p-chlorophenyl)piperazine (4CPP). Differentiation of these compounds is necessary in regulating them, and we report here the results of a study of a method to confirm these compounds using the present library. 相似文献
60.
We have succeeded in precisely determining the hyperfine interactions, particularly the isomer shifts, in the 149Sm Mössbauer transition. The difference in the nuclear radii between the ground and excited states is critical for the determination of isomer shifts but is relatively small in 149Sm. Therefore, the precise determination by 149Sm Mössbauer spectroscopy is difficult. The recent development of synchrotron-radiation-based Mössbauer spectroscopy allows the isomer shifts to be determined more precisely than previously with the help of wellcollimated synchrotron radiation. In particular, the time-window effect assists the precise determination of hyperfine interactions in the 149Sm Mössbauer transition because this effect enables us to measure spectra with higher energy resolution than natural linewidth determined by the lifetime of the excited states. Meanwhile, highenergy-resolution measurements to determine center shifts by SR-based Mössbauer spectroscopy enable us to observe the second-order Doppler shift, which has not been discussed, particularly for heavy Mössbauer nuclei. We have discussed the precise determination of isomer shifts and the observation of the second-order Doppler shift using 149Sm synchrotron-radiation-based Mössbauer spectroscopy. 相似文献