322,992 research outputs found
Politiek als evenwichtskunst
Full text linkHet boek telt 310 pagina's, kost /77,50 en is te bestellen bij iedere ,,,,boekhandel onder vermelding van ISBN 9060927990. "Politiek als evenwichtskunst" van Hoogerwerf richt zich op de fundamentele vragen rondom de Nederlandse politiek
Production of antioxidant molecules in Polygonum aviculare (L.) and senecio vulgaris (L.) under metal stress: A possible tool in the evaluation of plant metal tolerance
Full text linkPlants growing on heavy metal (HM)-polluted soils show toxicity symptoms, such as chlorosis and growth reduction, and undergo oxidative stress due to the formation of reactive oxygen species (ROS). Plants overcome oxidative stress by producing a wide range of antioxidant molecules, such as polyphenols and flavonoids. The aim of the present work was to study the accumulation of these molecules in response to increasing concentrations of Cd, Cr, Cu, Ni, Pb and Zn and to assess whether they can be used as a tool in assessing metal-related stress in Polygonum aviculare and Senecio vulgaris. On average, P. aviculare shoots accumulated lower amounts of metals than S. vulgaris shoots. The uptake of all six elements was correlated and proportional to their concentration in the nutrient solution (ρ > 0.9), with the bioaccumulation factor (BAF) being >1 for most of them. The present research demonstrated that 82% of the samples showed a good correlation (|ρ| > 0.5) between the level of polyphenols, flavonoids and antioxidant activity and the metal concentration in plant shoots, confirming that the metal stress level and production of phenolic compounds having antioxidant activity were strictly connected. Nonetheless, the mere quantification of these molecules cannot identify the type of metal that caused the oxidative stress, neither determine the concentration of the stressors. The five tested populations of each species did not show any specific adaptation to the environment of origin
Daily performance of a sustained attention task during light phase desynchronizes circadian oscillators in nocturnal rats.
No full textPrevious studies demonstrated that daily performance of a sustained attention task (SAT) for water reward during the light phase causes nocturnal rats to entrain to a diurnal activity pattern (Gritton et al., 2009). In addition, level of performance during the light phase was significantly lowered when compared to dark phase performance. We hypothesized that the shift to a diurnal activity pattern observed in animals trained during the light phase was due to desynchronization of the SCN and peripheral oscillators. To test this hypothesis, SAT practice occurred either during the light phase at ZT4 [SAT4] or during the dark phase at ZT16 [SAT16]. A control group practiced a daily fixed interval 9 s [FI-9] schedule of reinforcement at ZT4. Light/dark cycle was 12:12 and food was provided ad libitum. A second control group was handled at randomly selected times but was neither water-deprived nor performed [NP]. Circadian behavioral activity was recorded to verify the SAT effect on circadian rhythm. As circadian clock operates in most tissues via transcriptional feedback that involve the products of circadian clock genes, we hypothesized that expression of the clock genes present in the gastrointestinal tract (Hoogerwerf et al., 2007) were altered in SAT4 animals. Preliminary data show that SAT4 animals have dampened Period2 (Per2) rhythms in the colon when compared to FI-9 and NP animals. Results from ongoing experiments indicate that Per2 expression in the SCN is not altered by SAT4 practice; however, in non-SCN areas in the brain Per2 expression is attenuated. To better understanding the relationship between the SCN and the peripheral oscillators, additional biopsy data was collected from the heart, lung, liver, kidney, and stomach at 4 time points (ZT2, ZT8, ZT14, and ZT20). As circadian misalignment is associated with diabetes, obesity and metabolic syndrome, food intake and stool output of SAT4, SAT16, FI-9 and NP animals were collected. SAT4 animals’ food intake was significantly higher compared to NP and their gastrointestinal motility was altered as well. Furthermore, preliminary corticosterone data suggests that day/night differences are attenuated in SAT4 animals as compared to SAT16 animals, and SAT trained animals have overall elevated corticosterone levels compared to NP animals. This research provides new insights in understanding cognitive work-induced shifts in circadian rhythms, the cause and role of circadian abnormalities in neuropsychiatric disorders, obesity and metabolic syndrome, and it eventually will inform the development of treatments of such disorders
Diffusive author(s), cohesive author: Analysis of S/N (1994)
No full textThis study indicates the ways in which various aspects of the author(s) are brought forth in Dumb type’s performance art, the S/N production. Previous research has suggested a non-hierarchical organization of Dumb type and the absence of a “privileged author” in Dumb type’s collaborative work, S/N. However, the results that I have investigated from member’s interviews on the creative process of S/N along with my analysis of the recorded images of S/N, indicate a different aspect of the author(s). First, S/N was created through, so to speak, the collective ideas of the members of Dumb type. Further, S/N has at least nine quotations from previous performances, installations, and printed writings, besides the work-in-progress technique. Explicating one of the “author functions” as given by Michel Foucault, each text has plural subjects of the author. However, it has been revealed from members’ interviews that Teiji Furuhashi had a decision-making role in selecting the members’ ideas within the performance. Since then, S/N has had plural subjects of creation; however, Furuhashi is one of the subjects of creation along with the “privileged author.” S/N has plural authors (diffusive authors) yet at the same time, it has a “privileged author,” Teiji Furuhashi (cohesive author)
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Linking Data and Publications: Towards a Cross-Disciplinary Approach
Full text linkHoogerwerf M, Lösch M, Schirrwagen J, et al. Linking Data and Publications: Towards a Cross-Disciplinary Approach. International Journal of Digital Curation. 2013;8(1):244-254.In this paper, we tackle the challenge of linking scholarly information in multi-disciplinary research infrastructures. There is a trend towards linking publications with research data and other information, but, as it is still emerging, this is handled differently by various initiatives and disciplines. For OpenAIRE, a European cross-disciplinary publication infrastructure, this poses the challenge of supporting these heterogeneous practices. Hence, OpenAIRE wants to contribute to the development of a common approach for discipline-independent linking practices between publications, data, project information and researchers. To this end, we constructed two demonstrators to identify commonalities and differences. The results show the importance of stable and unique identifiers, and support a ‘by reference’ approach of interlinking research results. This approach allows discipline-specific research information to be managed independently in distributed systems and avoids redundant maintenance. Furthermore, it allows these disciplinary systems to manage the specialized structures of their contents themselves
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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No full textCan archives of audiovisual TV interviews be used to make authors more visible to students, and thereby reduce the learning gap between native and non-native language speakers in college classes? We examined students in a college course who learned about one scholar's ideas through watching an audiovisual TV interview (i.e., visible author format) and about another scholar's ideas through reading a formal text description (i.e., invisible author format). For the invisible author, native language speakers scored significantly higher than the non-native language speakers on a corresponding exam question (i.e., a cognitive measure), generated more words on the exam question (i.e., a motivational measure), and mentioned the author's name more often in answering the exam question (i.e., an affective measure). For the visible author, the groups did not differ on any of these measures. These findings provide evidence for the idea that making the author visible through audiovisual TV interviews can eliminate the learning gap between native and non-native language speakers. 3 Universities around the world serve students who are non-native speakers of th
The vanishing author in computer-generated works: a critical analysis of recent Australian case law
Full text linkAbstract
The use of software is ubiquitous in the creation of many copyright works, yet the requirement in copyright law that every work have a human author who engages in independent intellectual effort means that its use may prevent copyright subsistence. Several recent Australian cases have refocused attention on authorship as an essential criterion of copyright subsistence, and these cases suggest that much computer-produced output may be authorless and thus lack copyright protection. This article, the first in a two-part series, analyses how each case deals with the question of authorship of computer-produced works and why the use of software diminishes copyright protection for a significant number of computer-generated works. The article critiques the application of conventional notions of human authorship developed in the pre-computer age to modern productions and suggests alternative approaches to authorship that satisfy both the major objectives of copyright policy and the need to adapt to the computer age. The article argues that, without a broader judicial approach to authorship of computer-generated works, Parliament must remedy the lacuna in protection for these ‘authorless’ works. Possible solutions for reform are suggested. In a forthcoming article, the author comprehensively examines those reform proposals
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