反观念主义:精神追求的执迷

本文从反观念艺术家与西方艺术史;反观念艺术家与观代艺术;反观念艺术家与当代艺术;反观念主义的核心;观念艺术家的工作环境、大事记、展览;反观念主义的国际发展趋势;反观念艺术家的近期活动等各个方面分析阐述了反观念艺术对精神追求的执迷.     

Simulating the effect of environmental flow duration on seedling emergence from riparian seed banks of the Upper Hunter River,New South Wales

Passive riparian revegetation techniques are important tools in river rehabilitation. However, the utility of the sediment seed bank as a passive riparian regeneration option is poorly understood. After modelling a range of flows for field‐surveyed cross sections, a glasshouse seedling emergence experiment was undertaken to compare the effects of simulated flow duration on seedling emergence of desirable riparian species that occur on benches of the gravel‐bedded Hunter River near Muswellbrook, New South Wales. The duration of inundation did have an effect (although not always significant) on seed germination for most species. The most successful simulated flood conditions differed among species, with the control treatment (no inundation) resulting in the most germination for only two of the 10 species examined. These findings suggest that although environmental flows for the sole purpose of stimulating the riparian seed bank in order to facilitate regeneration of desirable riparian species would be largely ineffective and complicated by differing inundation responses among species, seed bank stimulation using environmental flows could be a value‐added benefit from flows allocated for other purposes. As such, consideration of flow duration is worthy of inclusion in environmental flow allocation planning.     

Inter-individual differences in the ability of human milk-fat extracts to enhance the genotoxic potential of the procarcinogen benzo[a]pyrene in MCF-7 breast cells

Environmental factors are believed to play an important role in cancer aetiology. Whether environmental pollutants act in isolation or in combination within mixtures remains unclear. Four human milk-fat extracts (from resident U.K. women) were screened for levels of organochlorinated and brominated compounds prior to being tested (1-50 mg-equiv) for micronucleus (MN)-forming activity in MCF-7 cells. Using the cytokinesis-block micronucleus assay, micronuclei (MNi) were scored in 1000 binucleate cells per treatment. Cell viability (% plating efficiency) and immunohistochemical detection of p53 induction were also measured. The effects of treatment with 1 mg-equiv of extract in combination with benzo[a]pyrene (BP) were also examined. BP-DNA adducts were detected and quantified by 32P-postlabeling analysis. Dose-related increases in MNi independent of pollutant concentrations were induced by milk-fat extracts. All four extracts elevated the percentage of p53 positive cells, although not always in a dose-related fashion. Some combinations resulted in profound low-dose-induced increases in MNi and significant elevations in the percentage of p53 positive cells, which occurred without further reduction in cell viability or mitotic rate. When one particular extract was combined with BP, a 100-fold increase in BP-DNA adducts was detected as compared with the levels induced by BP alone; an effect not induced by other extracts. This adduct-enhancing extract was fractionated into 14 fractions that were subsequently tested (1 mg-equiv of original extract) in combination with 0.01 microM BP. Fraction 1, into which nonpolar pollutants mostly eluted, enhanced MN-forming activity with BP. Surprisingly, the more polar and less likely to contain fat-soluble pollutants fractions 5 and 8 also enhanced MN-forming activity. No identifiable pollutants were present in these fractions. The results suggest that different environmental pollutants present in human tissue may influence the susceptibility of target cells to initiating events.     

The relationship between geomorphic river adjustment and management actions over the last 50 years in the Upper Hunter Catchment,NSW, Australia

The installation of 517 river works in the upper Hunter catchment, New South Wales over the last 50 years is linked to geomorphic river adjustment and flood history at catchment and reach scales. Nineteen types of works are classified into three categories consisting of engineering, heavy machinery and vegetation works. Since 1952, a transition in techniques has been detected from engineering‐based approaches, to river training/maintenance, to more ecosystem‐based approaches. From the 1950s to the mid‐1980s extensive river engineering was undertaken. Projects were concentrated along laterally unconfined rivers and were generally implemented after major phases of geomorphic river adjustment. Neither the type of river nor the type of river adjustment guided the implementation of differing management techniques or their distribution in the catchment. A blanket approach was adopted, applying the same types of works across all types of river. Emphasis was placed upon concerns for bank instability rather than bed instability. Hence in many cases, river works addressed the symptoms (i.e. bank erosion) rather than the underlying causes of river change (i.e. bed incision). Since the mid 1980s, techniques have evolved towards vegetation‐based procedures. The development of more effective river rehabilitation programmes requires that greater consideration is given to proactive strategies which build upon an understanding of geomorphic river adjustments at the catchment scale. Copyright © 2008 John Wiley & Sons, Ltd.     

Toward understanding distributed cognition in IT security management: the role of cues and norms

Information technology security management (ITSM) entails significant challenges, including the distribution of tasks and stakeholders across the organization, the need for security practitioners to cooperate with others, and technological complexity. We investigate the organizational processes in ITSM using qualitative analysis of interviews with ITSM practitioners. To account for the distributed nature of ITSM, we utilized and extended a distributed cognition framework that includes as key aspects the themes of cues and norms. We show how ITSM challenges foster under-use of cues and norms, which comprises a type of risk that may result in outcomes that are adverse to the organization’s interests. Throughout, we use scenarios told by our participants to illustrate the various concepts related to cues and norms as well as ITSM breakdowns.     

Technology of electrostatic spinning for the production of polyurethane tissue engineering scaffolds

Electrostatic spinning was investigated as an alternative to electrospinning to establish the potential of the technique for the production of a range of microfibrous polyurethane scaffolds with a variety of structures and properties related to the fabrication conditions. Tecoflex^® SG‐80A polyurethane was spun, systematically altering the spinning parameters, and the resulting scaffolds were characterised using scanning electron microscopy. Inter‐fibre separation was significantly affected by flow rate, spray distance and grid and mandrel voltages; fibre diameter by flow rate and mandrel voltage; void fraction by flow rate; fibre orientation by traverse speed and mandrel speed; and thickness by flow rate. Thus, scaffold (three‐dimensional) architecture may be controlled through manipulation of the electric fields and the fibre deposition (spinning parameters of flow rate and grid and mandrel voltages); and by spray movement and direction (spinning parameters of relative spray height, spray distance, traverse speed and mandrel speed). There were significant differences between the internal and external scaffold surfaces, due in part to the manner in which the surface of the mandrels was prepared. We conclude that the process may be used to produce a range of polyurethane scaffolds for use in many tissue engineering applications. Copyright © 2007 Society of Chemical Industry     

What are we monitoring and why? Using geomorphic principles to frame eco-hydrological assessments of river condition

Monitoring and assessment are integral components in adaptive management programmes that strive to improve the condition of river systems. Unfortunately, these procedures are generally applied with an emphasis upon biotic attributes and water quality, with limited regard for the geomorphic structure, function and evolutionary trajectory of a river system. Geomorphic principles convey an understanding of the landscape context within which ecohydrologic processes interact. Collectively, geo-eco-hydrologic understanding presents a coherent biophysical template that can be used to frame spatially and temporally rigorous approaches to monitoring that respect the inherent diversity, variability and complexity of any given river system. This understanding aids the development of management programmes that ‘work with nature.’ Unless an integrative perspective is used to monitor river condition, conservation and rehabilitation plans are unlikely to reach their true potential.     

The benefits of more electronic screen space on students’ retention of material in classroom lectures

Many lecture halls today have two or more screens to be used by instructors for lectures with computer-supported visual aids. Typically, this additional screen real estate is not used to display additional information; rather a single stream of information is projected on all screens. We describe a controlled laboratory study that empirically assesses the effect on students learning of using the increased classroom screen real estate to project an additional stream of information. We measured how well participants learned from a two-stream presentation compared to a one-stream presentation duplicated on both screens. Data indicate that using extra screen real estate can indeed improve learning. In particular, learning was most improved when pertinent prior information was shown alongside currently explained information. There is also evidence that visual comparisons were improved with parallel viewing using extra screen real estate. Subjective data gathered from participants showed a strong preference for learning with two streams of content over a regular one-stream presentation.     

Supporting Innovation through HR Policy: Evidence from the UK

This paper focuses on the relationship between the importance of innovation for organizations and their human resources policy. Drawing on survey findings, we examine the coherence of organizations’ utilization of HR recruitment, training and performance management policies to support and enhance firms’ innovation performance. Through a social–psychological perspective, we situate our findings in two diverse areas: the psychological literature, exploring the measurement of innovation, and second, with regard to the internal (with each other) and external (with broader organizational objectives) integration of distinct HR policy elements. Our surveyed organizations indicate that, whilst attaching importance to innovation, they fail to consistently translate this importance into coherent HR policies. Typically, HR policy rewarded non‐managerial employees for innovation, whilst managerial staff were expected to do so as a matter of course. This inconsistency is one source of resistance which blocks the generation of new ideas, and their implementation, organization‐wide.