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81.
This work analyses the potential role of nitrogen pollution technology of crop systems of Pujiang, County in Eastern China‘s Zhejiang Province, rice and vegetables are important cropping systems. We used a case study approach involving comparison of farmer practices and improved technologies. This approach allows assessing the impact of technology on pollution, is forward looking, and can yield information on the potential of on-the-shelf technology and provide opportunities for technology development. The approach particularly suits newly developed rice technologies with large potential of reducing nitrogen pollution and for future rice and vegetables technologies. The results showed that substantial reductions in nitrogen pollution are feasible for both types of crops. 相似文献
82.
Journal of Science Teacher Education - 相似文献
83.
Kristian Berg 《Reading and writing》2016,29(3):453-474
What determines consonant doubling in English? This question is pursued by using a large lexical database to establish systematic correlations between spelling, phonology and morphology. The main insights are: Consonant doubling is most regular at morpheme boundaries. It can be described in graphemic terms alone, i.e. without reference to phonology. In monomorphemic words, consonant doubling depends mostly on the word ending. Certain endings correlate with double consonants (e.g. <er> as in <summer>), while others correlate with single consonants (e.g. <it> as in <visit>). What is more, it is the graphemic form of the word ending that determines the presence or absence of double consonants: The word endings <-ic> and <-ick>, for example, are homophonous, but the former almost always occurs with single consonants (e.g. <panic>), the latter with double consonants (e.g. <derrick>). That makes graphemic word endings peculiar entities: Like suffixes, they are recurring and they have distributional properties—but unlike suffixes, they have no morphosyntactic or semantic function. 相似文献
84.
This article focuses on the concept of work‐organization in general and the adaptation of this concept to the (Swedish) school‐system in particular. One major point stressed by the authors is that the work‐organization of the school is not purely a question of technical forms of administration. When establishing work‐organization it is of crucial importance to take the functions of the school into consideration. This means that the first step is to focus the content of the organizational activities and then build up administrative forms which facilitate a goal‐oriented work. 相似文献
85.
Jaap Scheerens Hans Luyten Stéphanie M. van den Berg Cees A. W. Glas 《Educational Research and Evaluation》2013,19(1):15-39
As expectations of the economic impact of educational attainment are soaring (Hanushek & Woessmann, 2009) and conjectures about successful national educational reforms (Mourshed, Chijioke, & Barber, 2010) are welcomed by educational policy-makers in many countries, a careful assessment of the empirical evidence for these kinds of claims is needed. In this article, we present a methodology that was applied to an international data set. A multi-level model of education was used to present a hypothetical scenario, indicated as the “implementation scenario”. The scenario was tested on the Programme for International Student Assessment (PISA) 2009 data set by means of multi-level structural equation modelling. Although we find some evidence for direct effects and some support for straightforward implementation, the overall impact of malleable conditions at the system and school level appears disappointingly small. A theoretical strand of literature that would account for “limited malleability” is referred to in discussing these results. 相似文献
86.
87.
Dana Von Berg 《Journal of Interlibrary Loan, Document Delivery & Electronic Reserve》2013,23(5):337-345
Interlibrary loan borrowing staff at the University of Arizona Main Library, who handle difficult interlibrary loan requests, are taking a collaborative approach to obtaining unique, difficult-to-locate materials. A working group within the document delivery team meets weekly to share examples processed during the preceding week to increase the fill rate of challenging interlibrary loan requests. The group also established a wiki for the purpose of sharing resources that have been used to solve difficult requests. The wiki serves as an advanced interlibrary loan training resource that can be accessed by a greater number of staff, enabling them to gain the skills necessary to process difficult requests. 相似文献
88.
Birgit Anne van Driel Sharon R. van der Meer Klaas Jan van den Berg Joris Dik 《文物保护研究》2013,58(5):261-272
ABSTRACTTwentieth century paints often contain titanium dioxide and zinc oxide based white pigments that can range from photostable to highly photocatalytic. Photocatalytic pigments can cause the degradation of paint upon UV exposure, whereas photostable pigments may be benign or can protect paintings from degradation. Hence, knowing whether or not a pigment is photocatalytic is of high importance for risk assessment and the subsequent decision making process concerning storage and exposure conditions of objects. Here we present a proof of principle, focused on titanium white paints, for an easy-to-use and low-tech application of a commercial photocatalytic activity indicator ink (PAII) on embedded paint samples or cross sections. This test determines, qualitatively, if a photocatalytic pigment is present in a white paint sample. The PAII paint sample staining application shows an obvious color change, within five minutes of UV irradiation, for paint samples containing photocatalytic pigments. A microscope with a camera and a UV source are the only necessary equipment for the application of this method. A quantitative image processing protocol is also proposed as an extension of the staining method by applying open source software analysis to measure the color change using photographs. The test was evaluated on reference paints with well-characterized pigments and applied on samples from modern paintings by Piet Mondriaan, Robert Ryman, and Lucebert, indicating the presence of harmful photocatalytic pigments in these cases. The novel application of a commercial ink on paint samples offers a simple test, not just for assessment of photocatalytic activity of titanium white pigments, but which may in future be applied for the detection of photoactive forms of zinc white and other potentially harmful semiconductor pigments in art objects. 相似文献
89.
Kris Berg Richard W. Latin Thomas Baechle 《Research quarterly for exercise and sport》2013,84(4):395-401
Abstract This study investigated the timing of the trigger pull in relation to the cardiac cycle during air rifle shooting. Electrocardiogram) was recorded from 20 male nonelite rifle shooters in two separate testing sessions. The testing was conducted at an indoor shooting range using an optoelectronic shooting system. Each participant fired a shot in the standing position at a distance of 10 m from the target. The results showed that compared to random triggering, the shooters fired more often during the phase of 10–50% of the R wave-to-R wave (R-R) interval and less often during the phase of 50–90%. With regard to performance accuracy, the participants exhibited average or above average performance, when the shot occurred in the beginning (0–50%) and in the end (70–99%) of the R-R interval. The less optimal range for the triggering was located within the 50–70% phase of the R-R interval. The length of R-R interval (i.e., heart rate) did not affect the relation of shot placement within the cardiac cycle to the accuracy of shooting performance. The present results extend previous findings by showing that in air rifle shooting the optimum firing time within the cardiac cycle may be located in the systolic phase. It is argued that the systole-diastole dichotomy is not a sufficiently accurate way to investigate the effects of shot placement in the cardiac cycle. Further research is needed to examine the extent to which the relationship between the timing of triggering within the cardiac cycle and shooting performance depends a shooter's skill level. 相似文献
90.
Marian K. J. Dekker Berber R. Van den Berg Ad J. M. Denissen Margriet M. Sitskoorn 《Journal of sports sciences》2013,31(16):1550-1560
AbstractThis study focuses on a novel, easy to use and instruction-less method for mental training in athletes. Previous findings suggest that particular mental capacities are needed for achieving peak performance; including attentional control, focus, relaxation and positive affect. Electroencephalography (EEG) alpha brain activity has been associated with neural inhibition during processes of selective attention, for improving efficiency in information processing. Here we hypothesised that eyes open alpha power training by music teaches athletes to (1) learn to self-regulate their brain activity, and (2) learn to increase their baseline alpha power, herewith improving mental capacities such as focusing the allocation of attention. The study was double-blind and placebo-controlled. Twelve elite gymnasts were either given eyes open alpha power training or random beta power training (controls). Results indicate small improvements in sleep quality, mental and physical shape. In our first attempt at getting a grip on mental capacities in athletes, we think this novel training method can be promising. Because gymnastics is one of the most mentally demanding sports, we value even small benefits for the athlete and consider them indicative for future research. 相似文献