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51.
Terracciano A Abdel-Khalek AM Adám N Adamovová L Ahn CK Ahn HN Alansari BM Alcalay L Allik J Angleitner A Avia MD Ayearst LE Barbaranelli C Beer A Borg-Cunen MA Bratko D Brunner-Sciarra M Budzinski L Camart N Dahourou D De Fruyt F de Lima MP del Pilar GE Diener E Falzon R Fernando K Ficková E Fischer R Flores-Mendoza C Ghayur MA Gülgöz S Hagberg B Halberstadt J Halim MS Hrebícková M Humrichouse J Jensen HH Jocic DD Jónsson FH Khoury B Klinkosz W Knezević G Lauri MA Leibovich N Martin TA 《Science (New York, N.Y.)》2005,310(5745):96-100
Most people hold beliefs about personality characteristics typical of members of their own and others' cultures. These perceptions of national character may be generalizations from personal experience, stereotypes with a "kernel of truth," or inaccurate stereotypes. We obtained national character ratings of 3989 people from 49 cultures and compared them with the average personality scores of culture members assessed by observer ratings and self-reports. National character ratings were reliable but did not converge with assessed traits. Perceptions of national character thus appear to be unfounded stereotypes that may serve the function of maintaining a national identity. 相似文献
52.
Excess cyclin E-Cdk2 accelerates entry into S phase of the cell cycle and promotes polyploidy, which may contribute to genomic instability in cancer cells. We identified 20 amino acids in cyclin E as a centrosomal localization signal (CLS) essential for both centrosomal targeting and promoting DNA synthesis. Expressed wild-type, but not mutant, CLS peptides localized on the centrosome, prevented endogenous cyclin E and cyclin A from localizing to the centrosome, and inhibited DNA synthesis. Ectopic cyclin E localized to the centrosome and accelerated S phase entry even with mutations that abolish Cdk2 binding, but not with a mutation in the CLS. These results suggest that cyclin E has a modular centrosomal-targeting domain essential for promoting S phase entry in a Cdk2-independent manner. 相似文献
53.
The molecular nature of sweet taste receptors has not been fully explored. Employing a differential screening strategy, we identified a taste receptor gene, Tre1, that controls the taste sensitivity to trehalose in Drosophila melanogaster. The Tre1 gene encodes a novel protein with similarity to G protein-coupled seven-transmembrane receptors. Disruption of the Tre1 gene lowered the taste sensitivity to trehalose, whereas sensitivities to other sugars were unaltered. Overexpression of the Tre1 gene restored the taste sensitivity to trehalose in the Tre1 deletion mutant. The Tre1 gene is expressed in taste sensory cells. These results provide direct evidence that Tre1 encodes a putative taste receptor for trehalose in Drosophila. 相似文献
54.
Matsumoto Y Nakatsuji S Kuga K Karaki Y Horie N Shimura Y Sakakibara T Nevidomskyy AH Coleman P 《Science (New York, N.Y.)》2011,331(6015):316-319
Fermi liquid theory, the standard theory of metals, has been challenged by a number of observations of anomalous metallic behavior found in the vicinity of a quantum phase transition. The breakdown of the Fermi liquid is accomplished by fine-tuning the material to a quantum critical point by using a control parameter such as the magnetic field, pressure, or chemical composition. Our high-precision magnetization measurements of the ultrapure f-electron-based superconductor β-YbAlB(4) demonstrate a scaling of its free energy that is indicative of zero-field quantum criticality without tuning in a metal. The breakdown of Fermi liquid behavior takes place in a mixed-valence state, which is in sharp contrast with other known examples of quantum critical f-electron systems that are magnetic Kondo lattice systems with integral valence. 相似文献
55.
Nobuo SasakiTomoyuki Matsumoto Yoshinori IkenakaAkio Kazusaka Mayumi Ishizuka Shoichi Fujita 《Pesticide biochemistry and physiology》2011,100(2):135-139
The nitrofuran antibacterial agent furazolidone (FZ) is still used in veterinary medicine in some countries in the Middle and Far East. The present study aimed to show the effect of FZ on the activity of microsomal enzymes that metabolize FZ, and to identify the enzyme that contributes to FZ metabolism in chickens. Wistar rats and White Leghorn chickens were administered FZ once a day for four consecutive days. FZ metabolism was accelerated by FZ administration in chickens, but not in rats. The elevation of FZ metabolism coincided with the induction of NADPH cytochrome P450 reductase (CPR) activity in chickens, but such induction was not observed in rats. FZ metabolizing activities were inhibited in the presence of a CPR inhibitor (diphenylene iodonium chloride) but not by the addition of archetypal cytochrome P450 inhibitors (CO or n-octylamine). The preset study concluded that FZ accelerated its own metabolism in the chicken by induction of the activity of CPR. 相似文献
56.
Izumi Noguchi Takunori Katoh Shigekatsu Sakai Riki Iwata Masayuki Akiyama Hideyuki Ohtsuka Kouichi Sakata Hirohide Aga Yutaka Matsumoto 《Water, air, and soil pollution》2001,130(1-4):421-426
Snowcover surveys were carried out in Hokkaido, northern Japan. Snowpack samples were collected using a steel pipe at 80 sites in 1988, 69 sites in 1992, and 66 sites in 1996 and 2000 during the time when the water equivalents of the snowcover are the greatest. Spatial distribution maps of water equivalents and of the concentrations and the accumulated amounts of hydrogen, non-sea-salt sulfate and non-sea-salt calcium ion of the snowcover drawn by Kriging method are discussed. The distribution maps show that water equivalents and the accumulated amounts of hydrogen and non-sea-salt sulfate in all the sample years were largest in the Japan Sea region, as were the ion concentrations of hydrogen and non-sea-salt sulfate. It was estimated this was caused by air pollutants transported from a great distance. The ratio of areas below pH 5.0 increased temporally from 1988 (20%) to 1992, 1996 and 2000 (66–80%). This trend was estimated to be affected by a decline of non-sea-salt calcium concentrations derived from alkaline road dust. In addition, the effect of snowcover components was assessed by comparison between the acid loads of the snowcover and the acid neutralizing capacity of lake water. We found that lakes in the middle of the Japan Sea coast have the potential to be acidified by snowmelt. 相似文献
57.
Naoki Harada Shigeto Otsuka Masaya Nishiyama Satoshi Matsumoto 《Biology and Fertility of Soils》2005,41(1):46-51
A pot experiment was conducted to investigate the influences of indigenous phototrophs on methane (CH4) emissions from a paddy soil where rice straw was incorporated or was surface-applied. During the cultivation, half of the pots were covered with aluminum foil, except for the minimum space for rice plants, to prevent ambient light reaching the floodwater or the soil surface. Growth of oxygen-producing phototrophs was hardly observed in the unilluminated plots, whereas intensive growth of algae, duckweed and hydrophytes was found in the illuminated ones. Plant growth was not affected by the different treatments. Seasonal changes in CH4 emission determined by a closed chamber method indicated that illumination had no or only minor effects on CH4 emissions when rice straw was incorporated or was not applied, but significantly reduced CH4 emissions when rice straw was surface-applied. Methanogenesis occurring in the soil-floodwater interface was further investigated in two lab-scale model experiments measuring methanogenic activity. As a result, more activated methanogenesis was found in the surface-applied rice straw and the soil around the straw compared with the soil incubated without rice straw. The magnitude of the methanogenic activity in the rice straw incubated under illuminated conditions was significantly lower than that incubated in the dark. Consequently, this study demonstrates that methanogenesis in paddy soil occurs even in the soil-floodwater interface if plant residues like rice straw exist, and such methanogenesis is likely to be suppressed by growth of indigenous phototrophs under illumination. 相似文献
58.
K Takeba M Matsumoto Y Shida H Nakazawa 《Journal of the Association of Official Analytical Chemists》1990,73(4):602-604
A sensitive, selective analytical method has been developed for determination of phenol in honey by liquid chromotography (LC) with amperometric detection (AMD). Phenol is extracted with benzene from the distillate of honey. The benzene extract is washed with 1% sodium bicarbonate solution and then reextracted with 0.1N sodium hydroxide followed by cleanup on a C18 cartridge. Phenol is determined by reverse-phase LC with amperometric detection. An Inertsil ODS column (150 X 4.6 mm, 5 microns) is used in the determination. The mobile phase is a mixture (20 + 80 v/v) of acetonitrile and 0.01M sodium dihydrogen phosphate containing 2mM ethylenediaminetetraacetic acid, disodium salt (EDTA) with the pH adjusted to 5.0. The flow rate is 1 mL/min under ambient conditions. The applied potential of the AMD using a glassy carbon electrode is 0.7 V vs an Ag/AgCl reference electrode. Average recoveries of phenol added to honey were 79.8% at 0.01 ppm spiking level, 90.4% at 0.1 ppm, and 91.0% at 1.0 ppm. Repeatabilities were 3.4, 1.3, and 1.8%, respectively. The detection limit of phenol in honey was 0.002 ppm. For analysis of 112 commercial honey samples, the range and average values of 32 detected samples were 0.05-5.88 ppm and 0.71 ppm, respectively. 相似文献
59.
Yamada N Ozawa S Kageyama N Miyano H 《Journal of agricultural and food chemistry》2004,52(17):5329-5333
Food allergies represent an important health problem in industrialized countries, such that detection and quantitative analysis of the protein considered to be the main allergen is crucial. A dot-blot fluorescent staining method for the detection and quantitative analysis of protein residues in food grade amino acids and nucleic acids is presented. This method combines fluorescence staining with dot-blotting onto PVDF membrane. Several standard proteins, such as bovine serum albumin (66 kDa), lysozyme (14 kDa), ubiquitin (8.6 kDa), bovine insulin (5.7 kDa), and oxidized insulin B chain (3.5 kDa), were detectable at 0.1 ppm using SYPRO Ruby blot stain. Twenty-five different amino acids and two different nucleic acids of food grade were analyzed using this method combined with an internal standard addition method using BSA as an internal standard. All amino acids and nucleic acids were dissolved in 3.6% aqueous HCl and dot-blotted onto PVDF membrane before a large amount of amino acids and nucleic acid were removed. Protein residues and the internal standard protein immobilized on the membrane were stained using SYPRO ruby blot stain. The internal standard in all samples was detectable at 0.1 ppm. Samples were dissolved at 120 or 70 mg/mL, according to their solubility under acidic conditions. The detection limit of protein residues per weight was 0.8-1.4 ppm in amino acids and nucleic acids; residual protein was not detected in any sample. 相似文献
60.
Hideaki Matsumoto 《Soil Science and Plant Nutrition》2005,51(5):613-615
Aluminum (Al) is a major element in the soil; 30–40% of arable land is acidic. Solubilized Al ion in acid soils inhibits root elongation. Intensive research on the Al tolerance mechanism has been conducted in the past few decades. Mechanism of Al tolerance can be classified into Al exclusion mechanism and intracellular tolerance mechanism. Efflux of organic acids from roots upon receiving the Al signal is the major Al exclusion mechanism. Efflux of organic acids through the channel in the plasma membrane was confirmed, and the gene specifically encoding malate transporter in Al-tolerant wheat was discovered recently. The regulatory mechanism in the efflux of organic acids upon protein phosphorylation may be operative. The production of reactive oxygen species (ROS) and their scavenging system are thought to be important in the intracellular tolerance mechanism. 相似文献