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21.
We conducted a meta-analysis of age differences in predecisional information search (N = 1,304) that suggests that aging is associated with a small but significant decrease in predecisional information search (Hedges's g = –0.30). In addition, we investigated the consequences of limited information search for decision quality in real-world consumer environments using simulation methods. Overall, the results suggest that the aging decision maker can afford to neglect information because this leads to small losses in decision quality. In other words, less may be enough for the aging consumer. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
Larisa I. Privalova Boris A. Katsnelson Nadezhda V. Loginova Vladimir B. Gurvich Vladimir Y. Shur Yakov B. Beikin Marina P. Sutunkova Ilzira A. Minigalieva Ekaterina V. Shishkina Svetlana V. Pichugova Ludmila G. Tulakina Svetlana V. Beljayeva 《International journal of molecular sciences》2014,15(11):21538-21553
We used stable water suspensions of copper oxide particles with mean diameter 20 nm and of particles containing copper oxide and element copper with mean diameter 340 nm to assess the pulmonary phagocytosis response of rats to a single intratracheal instillation of these suspensions using optical, transmission electron, and semi-contact atomic force microscopy and biochemical indices measured in the bronchoalveolar lavage fluid. Although both nano and submicron ultrafine particles were adversely bioactive, the former were found to be more toxic for lungs as compared with the latter while evoking more pronounced defense recruitment of alveolar macrophages and especially of neutrophil leukocytes and more active phagocytosis. Based on our results and literature data, we consider both copper solubilization and direct contact with cellular organelles (mainly, mitochondria) of persistent particles internalized by phagocytes as probable mechanisms of their cytotoxicity. 相似文献
23.
Muhammad G. Dastgir Ludmila G. Peeva Andrew G. Livingston 《Chemical engineering science》2005,60(24):7034-7044
This study investigates the possibility of using a composite-supported polymeric liquid membrane (CSPLM) configuration for the Membrane Aromatic Recovery System (MARS). The membrane was prepared by impregnating the liquid membrane phase into the pores of a composite flat sheet membrane consisting of a microporous support and a thin non-porous layer. A polyvinylidenfluoride (PVDF) microporous support coated with a thin non-porous polydimethylsiloxane (PDMS) layer was chosen as a composite membrane due to its superior combination of mass transfer rates and chemical resistance among the membranes tested and polypropylene glycol (PPG) was used as a liquid membrane phase due to its high affinity for phenol. The resulting membrane showed uniform selectivity and operational stability under the continuous MARS operating conditions for more than two months. The mass transfer rates () were 5 times higher than those of the silicone rubber tubing () which is used in commercial scale MARS technology. The CSPLM also exhibited reduced water flux and low sodium ion transfer. The partition coefficient of phenol between PPG/water was measured as 84. A marked effect of ionic strength on partition coefficient of phenol was observed with partition coefficient increase to 134 when measured in the presence of 20 wt% KCl in phenol aqueous solution. 相似文献
24.
The consolidation of multiple workloads and servers enables the efficient use of server and power resources in shared resource pools. We employ a trace-based workload placement controller that uses historical information to periodically and proactively reassign workloads to servers subject to their quality of service objectives. A reactive migration controller is introduced that detects server overload and underload conditions. It initiates the migration of workloads when the demand for resources exceeds supply. Furthermore, it dynamically adds and removes servers to maintain a balance of supply and demand for capacity while minimizing power usage. A host load simulation environment is used to evaluate several different management policies for the controllers in a time effective manner. A case study involving three months of data for 138 SAP applications compares three integrated controller approaches with the use of each controller separately. The study considers trade-offs between: (i) required capacity and power usage, (ii) resource access quality of service for CPU and memory resources, and (iii) the number of migrations. Our study sheds light on the question of whether a reactive controller or proactive workload placement controller alone is adequate for resource pool management. The results show that the most tightly integrated controller approach offers the best results in terms of capacity and quality but requires more migrations per hour than the other strategies. 相似文献
25.
Ivan Kelnar Ivan Fortelný Ludmila Kaprálková Jiřina Hromádková 《Polymer Engineering and Science》2015,55(9):2133-2139
Effect of layered silicates on structure of microfibrillar composites (MFCs) with reinforcing PA6 fibrils formed in situ by melt drawing was studied. Clay was added to HDPE/PA6 MFC using different mixing protocols including simultaneous addition, application of pre‐made masterbatches with both constituents and their combinations. In all cases, majority of nanofiller (NF) was contained inside PA6 fibrils. On the other hand, fibrils dimensions were significantly affected by the clay addition protocol; their marked increase in the case of simultaneous addition of all components and application of HDPE/C30 nanocomposite indicate important effect of NF migration to the PA6 phase in the course of mixing and melt drawing. The effect of properties of PA6 and HDPE phases and NF migration on the morphology evolution is discussed. It is shown that the fiber shape and volume after sample drawing are controlled by the interplay between the dispersed fibril extension and coalescence. POLYM. ENG. SCI., 55:2133–2139, 2015. © 2015 Society of Plastics Engineers 相似文献
26.
27.
Investigating the Role of Conformational Effects on Laccase Stability and Hyperactivation under Stress Conditions
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Dr. Valerio Ferrario Dr. Alexey Chernykh Federica Fiorindo Dr. Marina Kolomytseva Dr. Loris Sinigoi Dr. Nina Myasoedova Dr. Diana Fattor Prof. Dr. Cynthia Ebert Prof. Dr. Ludmila Golovleva Prof. Dr. Lucia Gardossi 《Chembiochem : a European journal of chemical biology》2015,16(16):2365-2372
Fungal laccase from Steccherinum ochraceum 1833 displays remarkable stability under different harsh conditions: organic/buffer mixtures, thermal treatment, and microwave radiation. The behavior is particularly significant in the light of the sharp inactivation observed for two different fungal laccases. Laccase from S. ochraceum 1833 also displays hyperactivation under mild thermal treatment (60 °C). Molecular dynamics simulations at 80 °C explained how this laccase retains the geometry of the electron transfer pathway, thereby assuring electron transfer through the copper ions and thus maintaining its catalytic activity at high temperature. Spectroscopic studies revealed that the thermal activation corresponds to specific conformational changes in the protein. The results indicate that this laccase is potentially applicable under denaturing conditions that might be beneficial for the biotransformation of recalcitrant substrates. 相似文献
28.
Lubica Sobotova Jana Jurkovicova Ludmila Sevcikova 《The Science of the total environment》2010,408(6):1264-1270
Objective
The objective of our study was to investigate and evaluate the relationship between road traffic noise and cardiovascular risk.Methods
The study sample (n = 659; 36.9% male, 63.1% female university students, mean age 22.83 ± 1.58 years) included a group exposed to road traffic noise (n = 280, Leq,24 h = 67 ± 2 dB(A)) and a control group (n = 379, Leq,24 h = 58.7 ± 6 dB(A)). Subjective response was determined by a validated noise annoyance questionnaire. The ten year risk of developing a coronary heart disease event was quantified as an evaluation of cardiovascular risk (SCORE60, Framingham 10-year risk estimation and projection to the age of 60, relative risk SCORE chart).Results
Cardiovascular risk scores were significantly higher in the exposed group based on the Framingham scores projected to the age of 60, SCORE60 (AOR = 2.72 (95% CI = 1.21-6.15)) and the relative risk SCORE chart (AOR = 2.81 (1.46-5.41)).Conclusions
These findings highlight the association between road traffic noise and cardiovascular risk. 相似文献29.
Victor Spuskanyuk Oleksandr Davydenko Alla Berezina Oleksandr Gangalo Ludmila Sennikova Michael Tikhonovsky Dmitry Spiridonov 《Journal of Materials Processing Technology》2010,210(13):1709-1715
Effect of combined processing by the equal-channel angular hydroextrusion (ECAH), direct hydroextrusion (HE) and drawing (D) on properties of copper wire is discussed in the paper. The technique has been for the first time employed for hardening lengthy copper rods and wire and reaching the ultimate tensile strength σ = 686 MPa and the elongation to failure δ = 2% in the 0.5 mm diameter copper wire. These contrast with σ = 556 MPa and δ = 1.4% resulted from processing without ECAH. Electrical conductivity of the highest strength wire produced with ECAH and conductivity of a hardened wire produced without ECAH differ negligibly. 相似文献
30.
Richardson SD Thruston AD Rav-Acha C Groisman L Popilevsky I Juraev O Glezer V McKague AB Plewa MJ Wagner ED 《Environmental science & technology》2003,37(17):3782-3793
Using gas chromatography/mass spectrometry (GC/MS), we investigated the formation of disinfection byproducts (DBPs) from high bromide waters (2 mg/L) treated with chlorine or chlorine dioxide used in combination with chlorine and chloramines. This study represents the first comprehensive investigation of DBPs formed by chlorine dioxide under high bromide conditions. Drinking water from full-scale treatment plants in Israel was studied, along with source water (Sea of Galilee) treated under carefully controlled laboratory conditions. Select DBPs (trihalomethanes, haloacetic acids, aldehydes, chlorite, chlorate, and bromate) were quantified. Many of the DBPs identified have not been previously reported, and several of the identifications were confirmed through the analysis of authentic standards. Elevated bromide levels in the source water caused a significant shift in speciation to bromine-containing DBPs; bromoform and dibromoacetic acid were the dominant DBPs observed, with very few chlorine-containing compounds found. Iodo-trihalomethanes were also identified, as well as a number of new brominated carboxylic acids and 2,3,5-tribromopyrrole, which represents the first time a halogenated pyrrole has been reported as a DBP. Most of the bromine-containing DBPs were formed during pre-chlorination at the initial reservoir, and were not formed by chlorine dioxide itself. An exception wasthe iodo-THMs, which appeared to be formed by a combination of chlorine dioxide with chloramines or chlorine (either added deliberately or as an impurity in the chlorine dioxide). A separate laboratory study was also conducted to quantitatively determine the contribution of fulvic acids and humic acids (from isolated natural organic matter in the Sea of Galilee) as precursor material to several of the DBPs identified. Results showed that fulvic acid plays a greater role in the formation of THMs, haloacetic acids, and aldehydes, but 2,3,5-tribromopyrrole was produced primarily from humic acid. Because this was the first time a halopyrrole has been identified as a DBP, 2,3,5-tribromopyrrole was tested for mammalian cell cytotoxicity and genotoxicity. In comparison to other DBPs, 2,3,5-tribromopyrrole was 8x, 4.5x, and 16x more cytotoxic than dibromoacetic acid, 3-chloro-4-(dichloromethyl)-5-hydroxy-2-[5H]-furanone [MX], and potassium bromate, respectively. 2,3,5-Tribromopyrrole also induced acute genomic damage, with a genotoxic potency (299 microM) similar to that of MX. 相似文献