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Objective: The objective of this article was 2-fold: firstly, we wanted to examine whether the original Driving Anger Scale (DAS) and the original Driving Anger Expression Inventory (DAX) apply to German professional taxi drivers because these scales have previously been given to professional and particularly to nonprofessional drivers in different countries. Secondly, we wanted to examine possible differences in driving anger experience and expression between professional German taxi drivers and nonprofessional German drivers.Methods: We applied German versions of the DAS, the DAX, and the State–Trait Anger Expression Inventory (STAXI) to a sample of 138 professional German taxi drivers. We then compared their ratings to the ratings of a sample of 1,136 nonprofessional German drivers (Oehl and Brandenburg n.d.).Results: Regarding our first objective, confirmatory factor analysis shows that the model fit of the DAS is better for nonprofessional drivers than for professional drivers. The DAX applies neither to professional nor to nonprofessional German drivers properly. Consequently, we suggest modified shorter versions of both scales for professional drivers. The STAXI applies to both professional and nonprofessional drivers. With respect to our second objective, we show that professional drivers experience significantly less driving anger than nonprofessional drivers, but they express more driving anger.Conclusions: We conclude that the STAXI can be applied to professional German taxi drivers. In contrast, for the DAS and the DAX we found particular shorter versions for professional taxi drivers. Especially for the DAX, most statements were too strong for German drivers to agree to. They do not show behaviors related to driving anger expression as they are described in the DAX. These problems with the original American DAX items are in line with several other studies in different countries. Future investigations should examine whether (professional) drivers from further countries express their anger as proposed by the DAX. In addition, professional drivers experience less driving anger (DAS) and less general trait anger (STAXI) than nonprofessional drivers, but they report more driving anger expression (DAX) and more current general state anger (STAXI). Subsequent studies should therefore focus on different types of anger within the group of professional drivers. 相似文献
204.
Mass-cultivation of carbohydrate rich macroalgae, a possible solution for sustainable biofuel production 总被引:2,自引:0,他引:2
Stefan Kraan 《Mitigation and Adaptation Strategies for Global Change》2013,18(1):27-46
Global demand for bio-fuels continues unabated. Rising concerns over environmental pollution and global warming have encouraged the movement to alternate fuels, the world ethanol market is projected to reach 86 billion litres this year. Bioethanol is currently produced from land-based crops such as corn and sugar cane. A continued use of these crops drives the food versus fuel debate. An alternate feed-stock which is abundant and carbohydrate-rich is necessary. The production of such a crop should be sustainable, and, reduce competition with production of food, feed, and industrial crops, and not be dependent on agricultural inputs (pesticides, fertilizer, farmable land, water). Marine biomass could meet these challenges, being an abundant and carbon neutral renewable resource with potential to reduce green house gas (GHG) emissions and the man-made impact on climate change. Here we examine the current cultivation technologies for marine biomass and the environmental and economic aspects of using brown seaweeds for bio-ethanol production. 相似文献
205.
Kaluzhnaya OV Belikov SI Schröder HC Rothenberger M Zapf S Kaandorp JA Borejko A Müller IM Müller WE 《Die Naturwissenschaften》2005,92(3):128-133
In ancient Lake Baikal (East Siberia), freshwater sponges have diversified to an extraordinary degree. The skeleton of Lubomirskia baicalensis, which attains a size of up to 1 m, is constructed from spicules, which are cemented into longitudinal bundles. Our X-ray analysis revealed that the architecture of the specimens follows a highly ordered radiate accretive growth pattern. The spicules have a central axial canal with an axial filament inside. This organic filament is composed of silicatein, the major enzyme involved in silica formation of the spicules. We found that the specific activity of silicatein in samples from the non-growing (basal) zone is much lower than in those from the growth zone (tips) and that even the composition of this molecule differs in these regions. The present study shows for the first time that the turnover of silicatein, the major element of the axial canal of sponge spicules, changes within a sponge specimen depending on the region in which it is found. 相似文献
206.
Stefan Norra 《Environmental science and pollution research international》2009,16(5):539-545
Background, aim, and scope In 1875, the geoscientist Walter Suess introduced several spheres, such as the lithosphere and the atmosphere to promote a
comprehensive understanding of the system earth. Since then, this idea became the dominating concept for the understanding
of the distribution of chemical elements in the system earth. Meanwhile, due to the importance of human beings on global element
fluxes, the term anthroposphere was introduced. Nevertheless, in face of the ongoing urbanization of the earth, this concept
is not any more adequate enough to develop a comprehensive understanding of global element fluxes in and between solid, liquid,
and gaseous phases. This article discusses a new concept integrating urbanization into the geoscientific concept of spheres.
Main features No geological exogenic force has altered the earth’s surface during the last centuries in such an extent as human activity.
Humans have altered the morphology and element balances of the earth by establishing agrosystems first and urban systems later.
Currently, urban systems happen to become the main regulators for fluxes of many elements on a global scale due to ongoing
industrial and economic development and a growing number of inhabitants. Additionally, urban systems are constantly expanding
and cover more and more former natural and agricultural areas. For nature, urban systems are new phenomena, which never existed
in previous geological eras. The process of the globe’s urbanization concurrently is active with the global climate change.
In fact, urban systems are a major emitter for climate active gases. Thus, beside the global changes in economy and society,
urbanization is an important factor within the global change of nature as is already accepted for climate, ecosystems, and
biodiversity.
Results Due to the fact that urbanization has become a global process shaping the earth and that the urban systems are globally cross-linked
among each other, a new geoscientific sphere has to be introduced: the astysphere. This sphere comprises the parts of the
earth influenced by urban systems. Accepting urbanization as global ongoing process forming the astysphere comprehensively
copes with the growing importance of urbanization on the creation of present geologic formations.
Discussion Anthropogenic activities occur mainly in rural and urban environments. For long lasting periods of human history, human activities
mainly were focused on hunting and agriculture, but since industrialization, urbanized areas became increasingly important
for the material and energy fluxes of earth. Thus, it seems appropriate to classify the anthroposphere into an agriculturally
and an urban-dominated sphere, which are the agrosphere (Krishna 2003) and the astysphere (introduced by Norra 2007).
Conclusions We have to realize that urban systems are deposits, consumers, and transformers of resources interacting among each other
and forming a network around the globe. Since the future of human mankind depends on the sustainable use of available resources,
only a global and holistic view of the cross-linked urban systems forming together the astysphere provide the necessary geoscientific
background understanding for global urban material and energy fluxes. If we want to ensure worth-living conditions for future
generations of mankind, we have to develop global models of the future needs for resources by the global metasystem of urban
systems, called astysphere.
Perspectives The final vision for geoscientific research on the astysphere must be to design models describing the global process of urbanization
of the earth and the development of the astysphere with respect to fluxes of materials, elements, and energy as well as with
respect to the forming of the earth’s face. Besides that, just from the viewpoint of fundamental research, the geoscientific
concept of spheres has to be complemented by the astysphere if this concept shall fully represent the system earth.
相似文献
Stefan NorraEmail: |
207.
208.
Kees Klein Goldewijk Stefan C. Dekker Jan Luiten van Zanden 《Journal of Land Use Science》2017,12(5):313-337
Changes in land use and land cover are important in global climate change, but the many uncertainties in historical estimates seriously hamper climate modelling. We collected new data on estimated per capita land use over the last two millennia, using new data sources from the Humanities. In general, and in agreement with literature, we found that per capita land use indeed has not been constant in the past, but differ per region and over time. Land use in the distant past was mostly less than 1 ha/cap. However, the recently colonised regions show much higher values and have experienced a much higher per capita land use for the recent past. Most known trajectories follow a concave or bell-shaped curve towards the present. 相似文献
209.
Wolfgang Schaaf Michael Elmer Anton Fischer Werner Gerwin Rossen Nenov Hans Pretzsch Stefan Seifert Susanne Winter Markus Klemens Zaplata 《Environmental monitoring and assessment》2013,185(7):5965-5986
The objective of this paper is to present observations, results from monitoring measurements, and preliminary conclusions about the development of patterns and structures during the first 5 years of development of an artificial catchment starting from point zero. We discuss the high relevance of initial system traits and external events for the system development and draw conclusions for further research. These investigations as part of a Collaborative Research Center, aim to disentangle and understand the feedback mechanisms and interrelationships of processes and their co-development with spatial and temporal structures and patterns by studying an initial, probably less complex ecosystem. Therefore, intensive measurements were carried out in the catchment with regard to the development of surface structures, hydrological patterns, vegetation dynamics, water chemistry, and element budgets. During the first 5 years, considerable changes within the catchment were observed. Both internal and external factors could be identified as driving forces for the formation of structures and patterns in the artificial catchment. Initial structures formed by the construction process and initial substrate characteristics were decisive for the distribution and flow of water. External factors like episodic events triggered erosion and dissection during this initial phase, promoted by the low vegetation cover, and the unconsolidated sandy substrate. The transformation of the initial geosystem into areas with evolving terrestrial or aquatic characteristics and from a very episodic to a more permanent stream network and discharge, together with the observed vegetation dynamics increased site diversity and heterogeneity with respect to water and nutrient availability and transformation processes compared with the more homogenous conditions at point zero. The processes and feedback mechanisms in the initial development of a new landscape may deviate in rates, intensity, and dominance from those known from mature ecosystems. It is therefore crucial to understand these early phases of ecosystem development and to disentangle the increasingly complex interactions between the evolving terrestrial and aquatic, biotic, and abiotic compartments of the system. Long-term monitoring of initial ecosystems may provide important data and parameters on processes and the crucial role of spatial and temporal structures and patterns to solve these problems. Artificially created catchments could be a suitable tool to study these initial developments at the landscape scale under known, designed, and defined boundary conditions. 相似文献
210.
Dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) are used by saprophilous insects to locate breeding sites (decaying organic matter), and by brood-site deceptive flowers to attract such insects. However, little is known about the relative importance of these two compounds in eliciting electrophysiological and behavioral responses in the insects. Here, we compared the relative attractiveness of DMDS and DMTS to saprophilous flies in field choice experiments and tested whether potential differences in field responses can be explained by differences in electrophysiological antennal responses to these compounds. Field experiments revealed that the attractiveness of a mixture of these compounds is due to DMTS alone. This result was confirmed by electroantennographic recordings in which flies of four tested species of Calliphoridae (Lucilia sericata, L. caesar, Calliphora vicina, Protocalliphora azurea) and one Muscidae (Musca domestica) respond clearly to DMTS, but not to DMDS. In house flies, however, DMTS elicited electrophysiological responses only, not reflected in behavioral assays. Despite the fact that DMTS and DMDS exhibit similar chemical structures, both the electroantennographic and field responses from saprophilous flies to these two compounds strongly differed. Our study suggests that oligosulfide-responsive saprophilous flies rely on DMTS and not DMDS for finding appropriate breeding sites and that DMTS and not DMDS could act as a key mediator for pollinator attraction in brood-site deceptive plants. 相似文献