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161.
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
162.
163.
Addiction profoundly alters motivational circuits so that drugs become powerful reinforcers of behavior. The interoceptive system continuously updates homeostatic and emotional information that are important elements in motivational decisions. We tested the idea that interoceptive information is essential in drug craving and in the behavioral signs of malaise. We inactivated the primary interoceptive cortex in amphetamine-experienced rats, which prevented the urge to seek amphetamine in a place preference task. Interoceptive insula inactivation also blunted the signs of malaise induced by acute lithium administration. Drug-seeking and malaise both induced Fos expression, a marker of neuronal activation, in the insula. We conclude that the insular cortex is a key structure in the perception of bodily needs that provides direction to motivated behaviors. 相似文献
164.
165.
Zhu Y Murali S Stoller MD Ganesh KJ Cai W Ferreira PJ Pirkle A Wallace RM Cychosz KA Thommes M Su D Stach EA Ruoff RS 《Science (New York, N.Y.)》2011,332(6037):1537-1541
Supercapacitors, also called ultracapacitors or electrochemical capacitors, store electrical charge on high-surface-area conducting materials. Their widespread use is limited by their low energy storage density and relatively high effective series resistance. Using chemical activation of exfoliated graphite oxide, we synthesized a porous carbon with a Brunauer-Emmett-Teller surface area of up to 3100 square meters per gram, a high electrical conductivity, and a low oxygen and hydrogen content. This sp(2)-bonded carbon has a continuous three-dimensional network of highly curved, atom-thick walls that form primarily 0.6- to 5-nanometer-width pores. Two-electrode supercapacitor cells constructed with this carbon yielded high values of gravimetric capacitance and energy density with organic and ionic liquid electrolytes. The processes used to make this carbon are readily scalable to industrial levels. 相似文献
166.
Barata A Campo E Malfeito-Ferreira M Loureiro V Cacho J Ferreira V 《Journal of agricultural and food chemistry》2011,59(6):2543-2553
In the present work, the aroma profiles of wines elaborated from sound and sour rot-infected grapes as raw material have been studied by sensory analysis, gas chromatography-olfactometry (GC-O), and gas chromatography-mass spectrometry (GC-MS), with the aim of determining the odor volatiles most likely associated with this disease. The effect of sour rot was tested in monovarietal wines produced with the Portuguese red grape variety Trincadeira and in blends of Cabernet Sauvignon and sour rotten Trincadeira grapes. Wines produced from damaged berries exhibited clear honey-like notes not evoked by healthy samples. Ethyl phenylacetate (EPhA) and phenylacetic acid (PAA), both exhibiting sweet honey-like aromas, emerged as key aroma compounds of sour rotten wines. Their levels were 1 order of magnitude above those found in controls and reached 304 and 1668 μg L(-1) of EPhA and PAA, respectively, well above the corresponding odor thresholds. Levels of γ-nonalactone also increased by a factor 3 in sour rot samples. Results also suggest that sour rot exerts a great effect on the secondary metabolism of yeast, decreasing the levels of volatiles related to fatty acids and amino acid synthesis. The highest levels of γ-decalactone of up to 405 μg L(-1) were also found in all of the samples, suggesting that this could be a relevant aroma compound in Trincadeira wine aroma. 相似文献
167.
Paula Aguilera Fernando Borie Alex Seguel Pablo Cornejo 《Soil biology & biochemistry》2011,43(12):2427-2431
Arbuscular mycorrhizal spores and glomalin-related soil protein (GRSP) isolated from acid soils were analyzed using confocal laser scanning microscopy (CLSM) for Al detection. Mycorrhizal structures of Glomus intraradices produced under in vitro conditions as well as spores and GRSP from neutral and Cu-polluted soils were used as contrasting criteria. Spores and GRSP from soils with 7 and 70% Al saturation showed autofluorescence which increased especially at the highest soil Al level and when Al3+ solution was added. G.intraradices spores showed fluorescence only when exogenous Al3+ was added. On the contrary, spores and GRSP from neutral and Cu-polluted soils showed little or no significant fluorescence. This fluorescence shown by fungal structures and GRSP when subjected to high Al (of endogenous or exogenous origin) suggest a high capacity for Al immobilization, which could be an effective way to reduce Al activity and phytotoxicity in acid soils. 相似文献
168.
Jaime A. Ocampo-Hernández Patricia Tamez-Guerra Samuel Pineda Fernando Tamayo-Mejía Ariel Guzmán-Franco José I. Figueroa de la Rosa Ana Mabel Martínez 《Journal of pest science》2011,84(4):471-477
Entomopathogenic fungi represent excellent candidates for biological insecticides. Among the many entomopathogenic fungi, Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) is one of the most promising species. Here, we report the results of infection studies performed using four B. bassiana native isolates (Bb37, Bb38, Bb40, and Bb45) compared with the commercial product Mycotrol® (strain GHA) on adult Mexican bean beetle Epilachna varivestis Mulsant (Coleoptera: Coccinellidae), one of the most important pests of bean production in Mexico. First, single concentration (1 × 108 conidia mL?1) assays were carried out using all isolates applied using an immersion method. Examinations at 10 days after inoculation indicated that isolates Bb37, Bb38, and Bb40 significantly reduced adult survival, causing 60–75% mortality compared to the commercial strain GHA (33%) and control (29%). Second, using two selected isolates (Bb37 and Bb40), the mean lethal concentration values (LC50) were estimated for third instar larvae and adult E. varivestis. The LC50 values for Bb37 and Bb40 isolates decreased 5.26-fold and 3.19-fold, respectively, in third instars compared with adults. However, such difference for Bb40 isolate was not significant. Finally, an experiment, to compare the median survival time (MST) values between third instar and adult E. varivestis, was conducted using Bb37 and Bb40 at 1 × 109 conidia mL?1. MST values were significantly reduced against larvae (87 and 100 h) compared with adults (130 and 134 h) by Bb37 and Bb40, respectively. We conclude that native isolates of B. bassiana represent an important alternative for the control of E. varivestis. However, to demonstrate its effectiveness under field conditions, detailed studies are needed. 相似文献
169.
Barbosa J Freitas A Moura S Mourão JL Noronha da Silveira MI Ramos F 《Journal of agricultural and food chemistry》2011,59(22):11927-11934
Nitrofurans were broadly used as an extremely effective veterinary antibiotic especially in pig and poultry production farms. Because of fears of the carcinogenic effects on humans, the nitrofurans were banned from use in livestock production in many countries, including the European Union. The present study examines the accumulation, distribution, and depletion of furaltadone and nifursol and of their tissue-bound metabolites [3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ) and 3,5-dinitro-salicylic acid hydrazine (DNSAH), respectively, in poultry edible tissues (muscle, liver, and gizzards) following administration to chickens of therapeutic and subtherapeutic concentrations of both compounds. Nitrofurans determination was performed by high-performance liquid chromatography-diode array detection and liquid chromatography-tandem mass spectrometry, respectively, for feeds and for poultry tissues. Furaltadone and nifursol, in very low concentrations, were found in samples of muscle, liver, and chicken's gizzard collected from slaughtered animals after 5 weeks of treatment and no withdrawal time period. When a withdrawal time period of 3 weeks was respected, no detectable nitrofuran parent compounds was observed in all of the studied matrices. For AMOZ, concentrations of 270 μg/kg in meat, 80 μg/kg in liver, and 331 μg/kg in gizzard were determined after administration of a medicated feed with furaltadone (132 mg/kg), 3 weeks after withdrawal of treatment. For DNSAH, the concentration values obtained are much lower than those observed for AMOZ. For meat, liver, and gizzard, DNSAH concentrations of 2.5, 6.4, and 10.3 μg/kg, respectively, were determined, after administration of a medicated feed with nifursol (98 mg/kg), 3 weeks after withdrawal of treatment. The gizzard could be considered a selected matrix for nitrofuran residues evaluation in poultry, due to its capacity of retaining either nitrofuran parent compounds or metabolites in higher concentrations, regardless of the administered dose or of the respected withdrawal time period. 相似文献
170.