222 research outputs found

    Cosmic multi-muon bundles measured at DELPHI

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    The DELPHI detector at LEP, located 100 mm underground, has been used to detect the multi-muon bundles by cathode readout of its hadron calorimeter and its tracking detectors (TPC, muon chambers). The experimental apparatus allows us to study muon bundles originating from primary cosmic particles with energies in the interval 101410^{14} - 1017eV10^{17} eV. The cosmic events registered during the years 1999 and 2000 correspond roughly to 1.6106s1.6 10^6 s of effective run time. The aim of the work is to compare the measured muon multiplicity distributions and predictions of high energy interaction models for different types of primary particles and also to determine the absolute flux of events in certain muon multiplicity range. The presentation describes the current status of the analysis.Comment: 2 pages, 1 figure, presented at XXXVIIth Rencontres de Moriond Electroweak Interactions and Unified Theories 2002 (Young Scientists Forum

    A Study of Modified Characteristics of Hadronic Interactions

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    We have implemented ad-hoc modifications to the CORSIKA Monte-Carlo generator which allow us to simultaneously adjust the multiplicity, elasticity and cross-section of hadronic interactions with respect to the predictions of the Sibyll 2.3d interaction model, in order to assess whether a reasonable combination of changes (that is not excluded by current experimental data) could alleviate the observed tension between the model predictions and observed features of extensive air showers induced by ultra-high energy cosmic rays (UHECR). Previously, we have studied the effects of such changes on proton-initiated showers. Because a multitude of experimental data suggest that the primary composition of the UHECR is mixed, we have expanded the modification procedure to include nuclear projectiles in a consistent way based on the superposition model, in a similar manner as was used in the previous studies carried out using one-dimensional simulation methods. As we are using a fully three-dimensional approach, we can quantify the effects of the changes on both longitudinal and lateral features of the showers. With the inclusion of nuclear projectiles, we can study the impact of the changes on observable quantities for realistic primary beams as well as on the determination of the primary composition from data under the assumption of the modified hadronic interactions.Comment: 6 pages, 9 figures, a conference proceeding for UHECR202

    Modified Characteristics of Hadronic Interactions

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    All Sky Camera for the CTA Atmospheric Calibration work package

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    The All Sky Camera (ASC) is a passive non-invasive imaging system for rapid night sky atmosphere monitoring. By design, the operation of the ASC will not affect the measurement procedure of the CTA observatory, for which we discuss its application in this report. The data collected should enable improved productivity and increased measurement time for the CTA observatory. The goal of ASC is to identify cloud position, atmosphere attenuation and time evolution of the sky condition, working within the CTA Central Calibration Facilities (CCF) group. Clouds and atmosphere monitoring may allow near-future prediction of the night-sky quality, helping scheduling. Also, in the case of partly cloudy night sky the cameras will identify the uncovered regions of the sky during the operation time, and define potential observable sources that can be measured. By doing so, a higher productivity of the CTA observatory measurements may be possible

    Competition among native and invasive Phragmites australis populations: An experimental test of the effects of invasion status, genome size, and ploidy level

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    Among the traits whose relevance for plant invasions has recently been suggested are genome size (the amount of nuclear DNA) and ploidy level. So far, research on the role of genome size in invasiveness has been mostly based on indirect evidence by comparing species with different genome sizes, but how karyological traits influence competition at the intraspecific level remains unknown. We addressed these questions in a common‐garden experiment evaluating the outcome of direct intraspecific competition among 20 populations of Phragmites australis, represented by clones collected in North America and Europe, and differing in their status (native and invasive), genome size (small and large), and ploidy levels (tetraploid, hexaploid, or octoploid). Each clone was planted in competition with one of the others in all possible combinations with three replicates in 45‐L pots. Upon harvest, the identity of 21 shoots sampled per pot was revealed by flow cytometry and DNA analysis. Differences in performance were examined using relative proportions of shoots of each clone, ratios of their aboveground biomass, and relative yield total (RYT). The performance of the clones in competition primarily depended on the clone status (native vs. invasive). Measured in terms of shoot number or aboveground biomass, the strongest signal observed was that North American native clones always lost in competition to the other two groups. In addition, North American native clones were suppressed by European natives to a similar degree as by North American invasives. North American invasive clones had the largest average shoot biomass, but only by a limited, nonsignificant difference due to genome size. There was no effect of ploidy on competition. Since the North American invaders of European origin are able to outcompete the native North American clones, we suggest that their high competitiveness acts as an important driver in the early stages of their invasion

    INFLUENCE OF AGE, GENDER AND SIRE LINE ON YOUNG CATTLE BEHAVIOUR TRAITS

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    The aim of this study was to test effects of age, gender, and sire line on dairy cattle behaviour. We have analyzed results of ethological tests for 40 Holstein breed animals (23 males and 17 females), offsprings of three sires. Maintenance behaviour were observed at the age of 90, 130 and 170 days. Behaviour in the maze was conducted at the age of 119 days, an open-field test was applied at the age of 124, 168, and 355 days. The social behaviour was determined by feeding on 155th day of the age. The times and the number of periods in all activities of maintenance behaviour were changing significantly (P<0.001) according to the age. The total time of lying, lying with ruminating, ruminating, feeding was increasing from the age of 90 days to the age of 170 days, on the other hand the time of standing was decreasing. The times of total lying, lying with ruminating, total ruminating, feeding were increased, and time of standing was decreased from the age of 90 days to the age of 170 days. Calves spent more time lying on the left side than on the right side. The number of ruminating periods was increasing according to the age. Eating periods were decreasing from the age of 90 to 170 days. The most of lying periods were recorded at the age of 130 days. The differences between sex were found in total time of lying, lying on the right side (P<0.05), and the males rest longer and had more periods of lying than females. We have found differences in times of feeding (P<0.001), total lying, standing (P<0.01), and lying on the left side (P<0.05) according to sire by comparing behaviour of the calves. Sire genotypes were significantly manifested in period number of total lying (P<0.001), lying on the right side, feeding (P<0.01), and standing (P<0.05). Males stood in the first part of maze longer than females (P<0.001), also length of total standing was longer by bulls (P<0.01). Heifers took shorter time to leave the maze than bulls (P<0.05). Sire lineages significantly differed in times of standing in the first part of maze and maze leaving. We did not find any significant differences either among sire lineage groups or between genders in locomotor behaviour measured by the number of crossed squares in open-field test. During all observations were more mobile heifers. No significant differences were found between males and females in social behaviour. The sire line influenced only the number of total duels (P<0.001). We found significant positive relationship between live body weight and time of staying in the first part of maze (r=0.3957**), time of maze leaving (r=0.3720**), and number of total and win duels (0.4031**, 0.3216*). Significant relationships were recorded in almost maintenance behaviour activities (P<0.001). Consistency of locomotor behaviour was proved only between the ages of 124 and 168 days (r=0.3177*). Significant relationship between maze behaviours and number of crossed squares were found only in ages of 119 and 124 days (r=-0.3721**; r=- 0.4110**; r=-0.3994**)

    Agriculture in the Face of Changing Markets, Institutions and Policies: Challenges and Strategies

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    Since the late 1980s, agriculture in Central and Eastern European Countries (CEECs) has been under considerable adjustment pressure due to changing political, economic and institutional environments. These changes have been linked to the transition process, as well as the ongoing integration into the European Union and the world market. Reduced subsidies, increased environmental and food quality demands, as well as structural changes in the supply, processing and food retailing sector call for major structural adjustments and the improvement of farmersâ managerial abilities. Though such changes always carry significant threats to farms, they also offer new opportunities for the farms' entrepreneurial engagement. Upcoming changes in the agricultural environment and their possible consequences for farm structures across Europe are thus still timely subjects. The objective of the IAMO Forum 2006 is to contribute to the success of agriculture in the CEECs, as well as their neighboring countries, in todayâs increasingly competitive environment. Concrete questions the conference focuses on are: What are the most suitable farm organizations, cooperative arrangements and contractual forms? How to improve efficiency and productivity? Where do market niches lie and what are the new product demands? This book contains 33 invited and selected contributions. These papers will be presented at the IAMO Forum 2006 in order to offer a platform for scientists, practitioners and policy-makers to discuss challenges and potential strategies at the farm, value chain, rural society and policy levels in order to cope with the upcoming challenges. IAMO Forum 2006, as well as this book, would not have been possible without the engagement of many people and institutions. We thank the authors of the submitted abstracts and papers, as well as the referees, for their evaluation of the abstracts from which the papers were selected. In particular, we would like to express our thanks to OLIVER JUNGKLAUS, GABRIELE MEWES, KLAUS REINSBERG and ANGELA SCHOLZ, who significantly contributed to the organization of the Forum. Furthermore, our thanks goes to SILKE SCHARF for her work on the layout and editing support of this book, and to JIM CURTISS, JAMIE BULLOCH, and DÃNALL Ã MEARÃIN for their English proof-reading. As experience from previous years documents, the course of the IAMO Forum continues to profit from the support and engagement of the IAMO administration, which we gratefully acknowledge. Last but not least, we are very grateful to the Robert Bosch Foundation, the Federal Ministry of Nutrition, Agriculture and Consumer Protection (BMELV), the German Research Foundation (DFG), the Haniel Foundation and the Leibniz Institute of Agricultural Development in Central and Eastern Europe (IAMO) for their respective financial support.Agribusiness, Community/Rural/Urban Development, Farm Management, Industrial Organization, International Development, Labor and Human Capital, Land Economics/Use, Productivity Analysis,

    Organic Agriculture

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    The “Organic Agriculture” (OA) book provides anyone interested in this type of farming with a practically focused textbook. The book gives a basic summary of work covering all relevant themes on which the most competent authors, coordinated by Czech experts - Borivoj Šarapatka and Jirí Urban, provide definitive contributions valid not only within the Czech Republic. The book is recommended for practical farming but also as a textbook for teachers and students. The real value of the book is in the fact that it has been compiled by a number of OA specialists and institutions focusing on this area of agriculture - to meet the demand for a comprehensive publication. The book includes chapters on the history and present status of OA in Europe, the legal status of organic agriculture methods (in accordance with European Council Regulation (EC) No. 834/2007 and Commission Regulation No. 889/2008), the environmental effects of OA, plant production, soil, plant nutrition and fertilization, cultivation of crops, weed control, permanent grassland, organic fruit and vegetable-growing, organic viticulture and wine-making, animal husbandry and animal breeding
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