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341.
Hansson Patrik; R?nnlund Michael; Juslin Peter; Nilsson Lars-G?ran 《Canadian Metallurgical Quarterly》2008,23(3):531
Realistic confidence judgments are essential to everyday functioning, but few studies have addressed the issue of age differences in overconfidence. Therefore, the authors examined this issue with probability judgment and intuitive confidence intervals in a sample of 122 healthy adults (ages: 35-40, 55-60, 70-75 years). In line with predictions based on the na?ve sampling model (P. Juslin, A. Winman, & P. Hansson, 2007), substantial format dependence was observed, with extreme overconfidence when confidence was expressed as an intuitive confidence interval but not when confidence was expressed as a probability judgment. Moreover, an age-related increase in overconfidence was selectively observed when confidence was expressed as intuitive confidence intervals. Structural equation modeling indicated that the age-related increases in overconfidence were mediated by a general cognitive ability factor that may reflect executive processes. Finally, the results indicated that part of the negative influence of increased age on general ability may be compensated for by an age-related increase in domain-relevant knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
342.
关于参数化主义 尼尔·里奇与帕特里克·舒马赫的对谈 总被引:2,自引:0,他引:2
在对谈里,帕特里克·舒马赫把"参数化主义"设想为继文艺复兴、巴洛克及现代主义之后一种新的时代风格,捍卫了"参数化主义"作为21世纪全球化风格的观点。对他而言,"参数化主义"的定义与讨论基于其导致的结果,而非其采用的技术。因而,风格这一概念被重新阐释,作为构建和推动参数化主义全球运动的因素。为推动参数化主义从先锋成为主流,舒马赫借由尼克拉斯·卢曼的社会系统理论衍生出一种基于普遍社会理论的普遍建筑理论——建筑自组织系统理论,"参数化主义"正是基于此理论。这一理论把社会理解为一个交流系统,一切建筑设计相应地成为交流系统的设计。以"参数化符号学"为议题,交流系统设计可通过与智能体群聚模型的结合在设计过程中具体操作实现。 相似文献
343.
Formation of environmentally relevant brominated dioxins from 2,4,6,-tribromophenol via bromoperoxidase-catalyzed dimerization 总被引:1,自引:0,他引:1
Polybrominated dibenzo-p-dioxins (PBDD) are emerging environmental pollutants with structural similarities to the highly characterized toxicants polychlorinated dibenzo-p-dioxins. The geographical and temporal variations of PBDD in biota samples from the Baltic Sea do not display features that are normally related to anthropogenic sources such as incineration, and therefore the natural formation of PBDDs has been suggested. This study of the bromoperoxidase mediated oxidative coupling of 2,4,6-tribromophenol (an abundant substance that is naturally formed in marine systems) identified the formation of ppb-level yields of 1,3,6,8-tetrabromodibenzo-p-dioxin (1,3,6,8-TeBDD) through direct condensation. Additional TeBDDs (1,3,7,9-TeBDD, 1,2,4,7-TeBDD, and/or 1,2,4,8-TeBDD) and tri-BDDs (1,3,7-TrBDD and 1,3,8-TrBDD) were frequently formed but at lower yields. The formation of these TeBDDs probably proceeds via bromine shifts or Smiles rearrangements, whereas the TrBDDs may result from subsequent debromination processes. Because all of the congeners formed by oxidative coupling and subsequent reactions are also found in Baltic Sea biota, the results support the theory that PBDDs are formed from natural precursors. 相似文献
344.
Quartz crystal microbalance with dissipation monitoring (QCM-D) was used to investigate dextran adsorption to alumina and silica. Sensitive adsorption measurements combined with determination of nanometer-scale polymer conformations demonstrate the utility of this technique for studying biopolymer adsorption. The adsorbed amounts and polymeric structures of dextran were determined on A12O3 and SiO2 by real-time monitoring of resonance frequency and energy dissipation changes (deltaf and deltaD). After the sample was rinsed, the apparent mass of retained dextran was 83 ng/cm(2) on the alumina surface and 9 ng/cm2 on the silica surface based on the frequency and energy dissipation changes. The deltaD/deltaf ratios were significantly different on the two surfaces, indicating different conformations of the polymers. On alumina, the ratio changed as adsorption proceeded indicating changes of dextran conformation from the initial to latter adsorption steps. On silica, the ratio did not change during the experiments. Therefore, the dissipation and frequency data suggest significantly different mechanisms of dextran adsorption on alumina and silica surfaces. Molecular dynamics simulations of 12 monomeric units of dextran on a silica slab illustrated that H2O molecules lead to loosely bound dextran structure onto the SiO2 surface, consistent with the observed high-energy dissipation in the QCM-D experiments. 相似文献
345.
Katarina Kalavska Zuzana Sestakova Andrea Mlcakova Katarína Kozics Paulina Gronesova Lenka Hurbanova Viera Miskovska Katarina Rejlekova Daniela Svetlovska Zuzana Sycova-Mila Jana Obertova Patrik Palacka Jozef Mardiak Michal Chovanec Miroslav Chovanec Michal Mego 《International journal of molecular sciences》2021,22(15)
Chemoresistance of germ cell tumors (GCTs) represents an intensively studied property of GCTs that is the result of a complicated multifactorial process. One of the driving factors in this process is the tumor microenvironment (TME). Intensive crosstalk between the DNA damage/DNA repair pathways and the TME has already been reported. This study aimed at evaluating the interplay between the immune TME and endogenous DNA damage levels in GCT patients. A cocultivation system consisting of peripheral blood mononuclear cells (PBMCs) from healthy donors and GCT cell lines was used in an in vitro study. The patient cohort included 74 chemotherapy-naïve GCT patients. Endogenous DNA damage levels were measured by comet assay. Immunophenotyping of leukocyte subpopulations was performed using flow cytometry. Statistical analysis included data assessing immunophenotypes, DNA damage levels and clinicopathological characteristics of enrolled patients. The DNA damage level in PBMCs cocultivated with cisplatin (CDDP)-resistant GCT cell lines was significantly higher than in PBMCs cocultivated with their sensitive counterparts. In GCT patients, endogenous DNA damage levels above the cutoff value were independently associated with increased percentages of natural killer cells, CD16-positive dendritic cells and regulatory T cells. The crosstalk between the endogenous DNA damage level and specific changes in the immune TME reflected in the blood of GCT patients was revealed. The obtained data contribute to a deeper understanding of ongoing interactions in the TME of GCTs. 相似文献
346.
Population changes in a biofilm reactor for phosphorus removal as evidenced by the use of FISH 总被引:5,自引:0,他引:5
Falkentoft CM Müller E Arnz P Harremoës P Mosbaek H Wilderer PA Wuertz S 《Water research》2002,36(2):491-500
Induction of denitrification was investigated for a lab-scale phosphate removing biofilm reactor where oxygen was replaced with nitrate as the electron acceptor. Acetate was used as the carbon source. The original biofilm (acclimatised with oxygen) was taken from a well-established large-scale reactor. During the first run, a decrease in the denitrifying bio-P activity was observed after 1 month following a change in the anaerobic phase length. This was initially interpreted as a shift in the microbial population caused by the changed operation. In the second run, biomass samples were regularly collected and analysed by fluorescent in situ hybridisation (FISH) and confocal laser scanning microscopy (CLSM). Concurrently, samples were taken from the original reactor with oxygen as electron acceptor in order to investigate natural microbial fluctuations. A similar decrease in the activity as in the first run was seen after one month, although the phase lengths had not been varied. Hence, the decrease after 1 month in the first and second run should be seen as a start-up phenomenon. FISH could detect a noticeable shift in the microbial population mainly within the first 2 weeks of operation. Almost all bacteria belonging to the alpha subclass disappeared and characteristic clusters of the beta and gamma subclasses were lost. Small clusters of gram-positive bacteria with a high DNA G + C content (GPBHGC) were gradually replaced by filamentous GPBHGC. Most of the bacteria in the denitrifying, phosphate removing biofilm belonged to the beta subclass of Proteobacteria. The applied set of gene probes had been selected based on existing literature on biological phosphate removing organisms and included a recently published probe for a Rhodocyclus-like clone. However, none of the specific probes hybridised to the dominant bacterial groups in the reactors investigated. No noticeable changes were detected in the aerobic bench-scale reactor during this period, indicating that the observed changes in the lab-scale reactor were caused by the changed environment. 相似文献
347.
Screening of human antibiotic substances and determination of weekly mass flows in five sewage treatment plants in Sweden 总被引:6,自引:0,他引:6
Lindberg RH Wennberg P Johansson MI Tysklind M Andersson BA 《Environmental science & technology》2005,39(10):3421-3429
Twelve antibiotic substances for human use, including trimethoprim and representatives of the fluoroquinolone (FQ), sulfonamide (SA), penicillin (PE), cephalosporin (CE), nitroimidazole (NI), tetracycline (TC), and macrolide (MA) groups, were subjected to a screening study at five Swedish sewage treatment plants (STPs) during one week in 2002 and one week in 2003. The analytes were extracted from raw sewage water, final effluent, and sludge by solid-phase extraction (SPE) or liquid-solid extraction (as appropriate) and then identified and quantified by liquid chromatography/tandem mass spectrometry. The mostfrequently detected antibiotics in the matrices considered in this study were norfloxacin, ofloxacin, ciprofloxacin, trimethoprim, sulfamethoxazole, and doxycycline. The other analytes were only detected in a few samples. Analysis of the weekly mass flows through each STP showed that FQs were partly eliminated from the water during sewage water treatment and the highest amounts of these substances were found in sludge. Sulfamethoxazole and trimethoprim were mainly found in raw sewage water and final effluent, but these substances had balancing mass flows, indicating that they too can withstand sewage water treatment. The mass flow patterns for doxycycline were more complex, with high amounts occurring in sludge in some cases, suggesting thatthe behavior of this analyte may be more strongly influenced by the treatment process and other variables at individual STPs. The environmental load (the sum of the amounts in the final effluent and sludge) normalized to the number of inhabitants in the catchment area of each investigated STP compared with theoretical predictions based on consumption data (in parentheses) showed good correlations: norfloxacin, 0.8 (0.9); ofloxacin, 0.3 (0.2); ciprofloxacin, 1.3 (3.5); sulfamethoxazole, 0.2 (0.4); trimethoprim, 1.1 (1.0); and doxycycline, 0.7 (0.4) mg per person per week. The results show that reasonably accurate predictions of environmental load of these antibiotics can be time-effectively derived from consumption data without additional measurements. 相似文献
348.
Park J Bauer S Pittrof A Killian MS Schmuki P von der Mark K 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(1):98-107
The aim of this study is to elucidate whether combined environmental signals provided by nanoscale topography and by growth factors control cell behavior of mesenchymal stem cells (MSCs) in a synergistic or simply additive manner. Chondrogenic and osteogenic differentiation of MSCs is studied on vertically aligned TiO(2) nanotubes of size 15 and 100 nm with and without immobilized bone morphogenetic protein-2 (BMP-2). Although BMP-2 coating stimulates both chondrogenic and osteogenic differentiation of MSCs, the response strongly depends on the surface nanoscale geometry of the BMP-2-coated nanotubes. Chondrogenic differentiation is strongly supported on 100 nm BMP-2-coated nanotubes, but not on 15 nm nanotubes, which induce spreading and de-differentiation of chondrocytes. A similar response is observed with primary chondrocytes, which maintain their chondrogenic phenotype on BMP-2-coated 100 nm nanotubes, but de-differentiate on 15 nm nanotubes. In contrast, osteogenic differentiation is greatly enhanced on 15 nm but not on 100 nm BMP-2-coated nanotubes as shown previously. Furthermore, covalent immobilization of BMP-2 rescues MSCs from apoptosis occurring on uncoated 100 nm TiO(2) nanotube surfaces. Thus, combined signals provided by BMP-2 immobilized to a defined lateral nanoscale spacing geometry seem to contain environmental cues that are able to modulate a lineage-specific decision of MSC differentiation and cell survival in a synergistic manner. 相似文献
349.
Xin Zhou Si-Ming Wu Patrik Schmuki 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(43):2303306
In the present work, the spontaneous dewetting of thin Au layers on single crystalline anatase nanosheets into narrow-disperse Au nanoparticles is investigated. Patterns of the Au particles can be formed on the main facets of anatase that provide a high co-catalytic activity for photocatalytic generation of H2. Dewetting is distinctly influenced by the respective facets (001) and (101), the deposit thickness, and secondary thermal dewetting, but most strongly by the surface termination of the nanosheets. Fluoride termination not only leads to an enhanced Au-phobic behavior but strongly affects the co-catalytic activity for photocatalytic generation of H2. While fluoride termination with or without Au decoration is detrimental for hole transfer, the interplay of the Au co-catalyst and surface fluoride yields highly beneficial effect for electron transfer. This results in a three-times higher photocatalytic H2 production for the F-terminated surface. The findings suggest that dewetting of Au on surface fluorinated TiO2 is an effective way to modulate surface dewetting and achieve a strongly enhanced photocatalytic activity. 相似文献
350.
Luyao Wang Qingbo Wang Emil Rosqvist Jan-Henrik Smått Qiwen Yong Lippo Lassila Jouko Peltonen Thomas Rosenau Martti Toivakka Stefan Willför Patrik Eklund Chunlin Xu Xiaoju Wang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(24):2207085
Fabricating bio-latex colloids with core–shell nanostructure is an effective method for obtaining films with enhanced mechanical characteristics. Nano-sized lignin is rising as a class of sustainable nanomaterials that can be incorporated into latex colloids. Fundamental knowledge of the correlation between surface chemistry of lignin nanoparticles (LNPs) and integration efficiency in latex colloids and from it thermally processed latex films are scarce. Here, an approach to integrate self-assembled nanospheres of allylated lignin as the surface-activated cores in a seeded free-radical emulsion copolymerization of butyl acrylate and methyl methacrylate is proposed. The interfacial-modulating function on allylated LNPs regulates the emulsion polymerization and it successfully produces a multi-energy dissipative latex film structure containing a lignin-dominated core (16% dry weight basis). At an optimized allyl-terminated surface functionality of 1.04 mmol g−1, the LNPs-integrated latex film exhibits extremely high toughness value above 57.7 MJ m−3. With multiple morphological and microstructural characterizations, the well-ordered packing of latex colloids under the nanoconfinement of LNPs in the latex films is revealed. It is concluded that the surface chemistry metrics of colloidal cores in terms of the abundance of polymerization-modulating anchors and their accessibility have a delicate control over the structural evolution of core–shell latex colloids. 相似文献