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Summary  

The calculation of Hirsch's h-index is a detail-ignoring way, therefore, single h-index could not reflect the difference of time spans for scientists to accumulate their papers and citations. In this study the h-index sequence and the h-index matrix are constructed, which complement the absent details of single h-index, reveal different increasing manner and the increasing mechanism of the h-index, and make the scientists at different scientific age comparable.

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The long-term mineral fertilisation experiment set up on acidic brown forest soil in Gödöllő in 1972 has made it possible over the years to answer a number of questions. It became clear that, in general, increasing rates of NPK fertilisation only caused a significant increase in the yields obtained in the crop rotation at lower rates (150–300 kg NPK/ha). As time went on, rates higher than this caused yield depression. The continuous application of high fertiliser rates led to a substantial increase in the P and K contents of the ploughed layer and in the quantity of nitrate accumulating in the 3 m soil profile. An increase in the quantity of nutrients was associated with a reduction in the pH and in the content of Ca and Mg. When mineral fertilisation was omitted for six years, there was a substantial reduction in the P and K contents of the ploughed layer.

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Abstract  

During the period 1985–1995 Daniel Koshland was Editor-in-Chief of the journal Science. As such he exerted a huge influence on all aspects related to content and lay-out of the journal. This study compares Science’s bibliometric characteristics between three periods: a pre-Koshland (1975–1984) period, the Koshland period (1985–1995) and the post-Koshland period (1996–2006). The distributions of document types, the country/territory and institutional distribution of authors, co-authorship data and disciplinary impact measured by subject categories of citations are studied. These bibliometric characteristics unveil some of the changes the journal went through under the leadership of Daniel Koshland.

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Abstract  

The paper examines the qualitative as well as quantitative indicators for the assessment of the scientific publication activities of 32 countries, with special attention to the Zipf-Pareto distribution of those indicators. Also discussed is the linear relationship between the number of first authors of scientific papers in a given country and the number of papers it produced. Based on these discussions, a comprehensive indicator combining the merits of quantitative and qualitative indicators is suggested. The ranking of the 32 countries by this indicator is found to follow also Zipf-Pareto distribution.

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Abstract  

On the basis of the measured frequency distribution of China"s inter-regional co-authored papers covered by the Chinese Science Citation Database, this paper shows the pattern of China"s inter-regional research collaboration (IRRC), and analyzes how the collaborative pattern was formed. A new method is used to calculate the expected value matrix based on an observed value matrix of IRRC, which is asymmetric and has no diagonal elements. The results fall into three groups. 1) Regional scientific productivity affects both the collaborative preference and ranking of authors" name; 2) geographical proximity is an important factor determining the pattern of IRRC; 3) when using Salton"s measure, regional mean collaborative strength increases as the regional productivity increases, and as the distance between two regions decreases.

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Maize is one of the most important crops in Hungarian crop production, making up 70-72% of forage consumption. Due to high energy prices and the rapidly increasing costs of drying, the need for maize hybrids with shorter growing seasons is increasing. Farmers require hybrids with a grain moisture content of 20-25% at harvest, making them suitable for storage with less drying.  In order to avoid excessive costs and workloads during harvest, it is wise to cultivate a mixture of hybrids with longer and shorter growing seasons as well as with slower and faster drying down rates.  The effect of fertilization on the yield components and moisture content of maize was examined, using the data from a two-year survey on the hybrid MV 484 SC, with five fertilizer treatments in 1998, and a control and three (0, 90 and 150 kg N/ha) nutrient levels in 1999.

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