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161.
This article appraises the career of architect Ralph Erskine focusing on the context for his contribution to Swedish and British social housing and planning. Erskine's formative experience during the 1930s and his subsequent transnational career are utilized to explore the mutual influences of planning ideals across national boundaries. The Garden City ideal, Functionalism and the urban village concept are considered for their long-term contribution to his work. In addition, vernacular architecture and participatory planning are explored as influences on the evolution of his community architecture vision by the 1970s. Drawing on evidence from urban developments in Britain and Sweden, the discussion demonstrates that Erskine's cultural transfer of international planning ideals essentialized aspects of British and Swedish historical culture. The article concludes with a discussion of the 1970s and Erskine's role in the redevelopment of Byker in Newcastle upon Tyne. This process was hailed as a pioneer moment in the English community architecture movement. However, this study demonstrates that Erskine should be distinguished from the grassroots activism of the community architecture movement. Rather the discussion emphasizes that his participatory planning was underpinned by a structural tension between social engineering and democratic participation that was generated and reinforced by his transnational career.  相似文献   
162.
Dialkyl phthalate esters (DPEs) are widely used chemicals, with over 4 million tonnes being produced worldwide each year. On the basis of their octanol-water partition coefficients (Kow), which range from 10(1.61) for dimethyl phthalate to 10(9.46) for di-iso-decyl phthalate, certain phthalate esters have the potential to bioconcentrate and biomagnify in aquatic food webs. However, there are no reported field studies on the trophodynamics of phthalate ester in aquatic food webs. This study reports the distribution of 8 individual phthalate esters (i.e., dimethyl, diethyl, di-isobutyl, di-n-butyl, butylbenzyl, di(2-ethylhexyl), di-n-octyl, and di-n-nonyl) and 5 commercial isomeric mixtures (i.e., di-iso-hexyl (C6), di-iso-heptyl (C7), di-iso-octyl (C8), di-iso-nonyl (C9), and di-iso-decyl (C10)) in a marine aquatic food web. DPE concentrations were determined in 18 marine species, representing approximately 4 trophic levels. Co-analysis of DPEs and 6 PCB congeners (i.e., PCB-18, 99, 118, 180, 194, and 209) in all samples produced a direct comparison of the bioaccumulation behavior of PCBs and DPEs. Lipid equivalent concentrations of the PCBs increased with increasing trophic position and stable isotope ratios (delta15N). The Food-Web Magnification Factor (FWMF) of the PCB congeners ranged from 1.8 to 9.5. Lipid equivalent concentrations of low and intermediate molecular weight DPEs (i.e., C1-C7 DPEs: dimethyl, diethyl, di-iso-butyl, di-n-butyl, benzylbutyl, and C6 and C7 isomers) did not exhibit statistically significant trends with trophic position or stable nitrogen isotope ratios (delta15N) in the food web and FWMFs were not significantly different from 1. Lipid equivalent concentrations of the high-molecular-weight DPEs (i.e., C8-C10 DPEs: di(2-ethylhexyl), di-n-octyl, di-n-nonyl, C8, C9, and C10) declined significantly with increasing trophic position and stable isotope ratios (delta15N), producing FWMFs between 0.25 and 0.48. These results show that all DPEs tested did not biomagnify in the studied aquatic food web whereas PCBs did biomagnify.  相似文献   
163.
This paper establishes a connection between structure sensitive categorial inference and classical modal logic. The embedding theorems for non-associative Lambek Calculus and the whole class of its weak Sahlqvist extensions demonstrate that various resource sensitive regimes can be modelled within the framework of unimodal temporal logic. On the semantic side, this requires decomposition of the ternary accessibility relation to provide its correlation with standard binary Kripke frames and models.  相似文献   
164.
Polyamidoamines were synthesized by Michael-type polyaddition reaction and conjugates characterized by 1H NMR, 31 Mosmann, T. Rapid Colorimetric Assay for Cellular Growth and Survival: Application to Proliferation and Cytotoxicity Assays. J. Immunol. Meth. 1983, 65, 5563.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]P NMR, FTIR, SEM, and EDX. The biological evaluation of the new materials revealed 12–30% inhibition of the human breast cancer cells (MCF7) and 25% of the Plasmodium falciparum malaria parasites by the conjugates. The hemolysis assay revealed that these materials did not have any effect on the host red blood cell membrane. The release mechanism of neridronate followed Korsmeyer–Peppas model at pH 1.2 with a diffusion coefficient of 0.45 indicating a Fickian diffusion mechanism; Higuchi model at pH 6.0 thus indicating a diffusion mechanism.  相似文献   
165.
McVey  Claire  Logan  Natasha  Thanh  Nguyen T. K.  Elliott  Christopher  Cao  Cuong 《Nano Research》2019,12(3):509-516

Detection of enzyme biomarkers originating from either bio-fluids or contaminating microorganisms is of utmost importance in clinical diagnostics and food safety. Herein, we present a simple, low-cost and easy-to-use sensing approach based on the switchable peroxidase-mimicking activity of plasmonic gold nanoparticles (AuNPs) that can catalyse for the oxidation of 3,3’,5’5-tetramethylbenzidine (TMB) for the determination of protease enzyme. The AuNP surface is modified with casein, showing dual functionalities. The first function of the coating molecule is to suppress the intrinsic peroxidase-mimicking activity of AuNPs by up to 77.1%, due to surface shielding effects. Secondly, casein also functions as recognition sites for the enzyme biomarker. In the presence of protease, the enzyme binds to and catalyses the degradation of the coating layer on the AuNP surface, resulting in the recovery of peroxidase-mimicking activity. This is shown visually in the development of a blue colored product (oxidised TMB) or spectroscopically as an increase in absorbance at 370 and 650 nm. This mechanism allows for the detection of protease at 44 ng·mL−1 in 90 min. The nanosensor circumvents issues associated with current methods of detection in terms of ease of use, compatibility with point-of-care testing, low-cost production and short analysis time. The sensing approach has also been applied for the detection of protease spiked in ultra-heat treated (UHT) milk and synthetic human urine samples at a limit of detection of 490 and 176 ng·mL−1, respectively, showing great potential in clinical diagnostics, food safety and quality control.

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166.
Human CD48, a membrane‐bound, glycosylphosphatidylinositol (GPI)‐linked glycoprotein, is a potential tumour target for the treatment of leukaemias and lymphomas. CD48 is expressed on T‐ and B‐cells, however <5% of CD34+ progenitor cells express CD48. A truncated, 45 kDa soluble form of the full length CD48 was expressed in Chinese hamster ovary (CHO) cells, and was shown to consist of a broad range of charge isoforms, with the most abundant isoforms between pI 4.5 and 5.0. The truncated form of CD48 was shown to bind to antibodies raised against native, GPI‐linked CD48 by surface plasmon resonance analysis. A synthetic, human, scFv immunoglobulin gene library was screened against recombinant CD48 by phage display, and an scFv antibody fragment, (designated N2A) was isolated after four rounds of biopanning. N2A was reassembled as a human IgG1 human monoclonal antibody, expressed in CHO cells and the binding of IgG1‐N2A to recombinant CD48 was confirmed by surface plasmon resonance. Flow cytometry studies of IgG1‐N2A binding to Raji cells showed the specificity of N2A for GPI‐linked CD48 was conserved, and presents the potential for IgG1‐N2A as a lead antibody candidate for the treatment of white blood cell malignancies. Copyright © 2005 Society of Chemical Industry  相似文献   
167.
In 2 experiments, an error-detection approach was used to determine whether 3-year-olds' perseverative errors on the postswitch phase of the Dimensional Change Card Sort (DCCS) are due to lack of response control or representational inflexibility. In Experiment 1, 3-, 4-, and 5-year-olds watched a puppet sort perseveratively on the postswitch phase and evaluated its responses. Most 4- and 5-year-olds detected the puppet's perseverative errors, whereas most 3-year-olds failed to do so despite detecting errors on a simpler card sort. Experiment 2 revealed that 3-year-olds who failed to correctly evaluate the puppet's behavior tended to fail their own DCCS. Results imply that perseveration on the DCCS cannot be attributed to difficulty inhibiting prepotent motor responses. Instead, changes in rule use between 3 and 5 years of age are interpreted in terms of the development of representational flexibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
168.
In their recent article, N. Spillane and G. Smith (see record 2007-06095-002) suggested that reservation-dwelling American Indians have higher rates of problem drinking than do either non–American Indians or those American Indians living in nonreservation settings. These authors further argued that problematic alcohol use patterns in reservation communities are due to the lack of contingencies between drinking and “standard life reinforcers” (SLRs), such as employment, housing, education, and health care. This comment presents evidence that these arguments were based on a partial review of the literature. Weaknesses in the application of SLR constructs to American Indian reservation communities are identified as is the need for culturally contextualized empirical evidence supporting this theory and its application. Cautionary notes are offered about the development of literature reviews, theoretical frameworks, and policy recommendations for American Indian communities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
169.
We reviewed 25 international and 10 Australian studies published between 1999 and 2004 for evidence of individual and organizational impacts of stress in the health and community services (HCS) sector. Several HCS occupations showed high levels of distress compared to Australian population data. Results were consistent with the Job Demands-Resources model: High demands (e.g., workload, emotional) combined with low resources (e.g., control, rewards, support) were associated with adverse health (e.g., psychological, physical) and organizational impacts (e.g., reduced job satisfaction, sickness absence). Australian-specific issues included rural and remote work and the complex role of Aboriginal Health Workers. Strong associations between modifiable work factors and adverse outcomes provide a rationale for primary preventive policy development by occupational health and safety regulators and workers' compensation authorities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
170.
The authors investigated empirical research into occupational stress interventions conducted in Australia within the past 10 years. They focused on evidence published and the quality of the evidence base. All intervention studies were conducted in the public sector. Only 1 study reached the gold standard in evidence-based research. Most interventions were individually focused, despite the preponderance of research identifying risky work environment stressors. Results suggest a paucity of published information regarding what works with occupational stress interventions in Australia and an urgent need for further research in the area, particularly focusing on the private sector, rural workers, and scientific evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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