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Search Results: 1 - 10 of 2565 matches for " Gerhard Glatzel "
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Measuring Soil Fertility under Hagenia abyssinica (Bruce) J. F. Gmel by the Biotest Method
Biruktayet Assefa,Gerhard Glatzel
International Journal of Agronomy , 2010, DOI: 10.1155/2010/845087
Abstract: The experiment was conducted at the Forestry Research Center, Ethiopia in 2008. Soil was sampled under the canopy of Hagenia abyssinica and from farmland area adjacent to the forest to measure fertility of soils by using the biotest with linseed (Linum usitatissimum L.), barley (Hordeum vulgare L.), and wheat (Triticum aestivum L.) as indicators. The experimental design was a completely randomized design comprising of 20 seedlings per study site. Seeds were seeded into polythene plastic bags. Seedling emergence, germination, and survival rate were recorded. Plant height and root collar diameter were measured. Final weight of fresh biomass was measured, and each component was oven-dried at 70°C. Dry weight was recorded at constant weight. Significant differences ( ) were observed between soil treatments. Plants grown on Hagenia-influenced soils attained better performance, suggesting the beneficial role of Hagenia abyssinica in enhancing soil fertility status which in turn results in higher productivity. 1. Introduction In Ethiopia, land degradation in the form of soil erosion and declining soil fertility is a serious constraint to agricultural productivity as well as economic development [1–3]. Land cover change triggered by agricultural land expansion and heavy livestock pressure are the proximate causes for degradation [4–6]. Some of the noticeable problems of soil fertility loss in the highlands include using dung and crop residues as household fuels and animal feeds, declining fallow periods, soil and organic matter burning (guie), and low use of chemical fertilizers [7]. Though the farming system in most part is mixed crop-livestock, nutrient flows between the two are predominantly one sided, with feeding of crop residues to livestock but little or no dung being returned to the soil [7]. Fertility replenishment can only be sustained if the nutrients removed are returned to the soil through addition. Trees on crop land have potential to improve soil fertility due to their organic inputs with nutrient recycling through mineralization [8–12]. Because soils in many parts of Ethiopia have low fertility, farmers are trying to apply inorganic fertilizers to replenish plant nutrients in their crop land. However, with the rising costs of farm inputs, this is becoming less of an option for the majority who do not have enough cash to purchase fertilizers. Therefore, it is critical to look for an option by examining trees that can improve top soil fertility through addition of litter. Hagenia abyssinica (Bruce) J. F. Gmel is an indigenous broad-leaved
Ethnomedicinal uses of Hagenia abyssinica (Bruce) J.F. Gmel. among rural communities of Ethiopia
Biruktayet Assefa, Gerhard Glatzel, Christine Buchmann
Journal of Ethnobiology and Ethnomedicine , 2010, DOI: 10.1186/1746-4269-6-20
Abstract: Plants have played a vital role in the prevention and treatment of disease since prehistoric times. People in different parts of the world depend on plant resources for their basic needs and are aware of many useful species occurring in their ecosystem. They have continuously developed their knowledge of traditional plant uses and plant resource management [1-4]. Traditional knowledge is described as 'a cumulative body of knowledge, practice and belief, evolving by adaptive processes and handed down through generations by cultural transmission, about the relationship of living beings (including humans) with one another and with their environment' [2]. In many countries of Africa, Asia and Latin America people depend on traditional knowledge and medicinal plants to meet some of their primary health care needs. For instance in Africa up to 80% of the population use traditional medicine for primary health care [5]. Likewise, many Ethiopian communities are dependent on local plant resources for medicine. Ethiopia is endowed with diverse biological resources due to significant geographical diversity, which favored the formation of different habitat and vegetation zones. Ethiopia is also home to a diverse mix of ethnic, cultural and linguistic groups. This diverse combination of social and cultural backgrounds contributed much to the existence of rich indigenous knowledge, including managing and using medicinal plants against human and livestock ailments. Plants have been used as a source of medicine in Ethiopia for a long time. More than 80% of the Ethiopian people are dependent on plants for their health service [6]. More than 95% of traditional medical preparations in the country are of plant origin [7]. Medicinal plants and knowledge of their uses provide a vital contribution to human and livestock health care needs. The importance of medicinal plants to treat human and livestock ailments in most parts of Ethiopia is stated by various authors [8-14].Hagenia abyssinica
Sympathetic Prions
Markus Glatzel
The Scientific World Journal , 2001, DOI: 10.1100/tsw.2001.258
Abstract:
Hard x-ray emission spectroscopy: a powerful tool for the characterization of magnetic semiconductors
Mauro Rovezzi,Pieter Glatzel
Physics , 2013, DOI: 10.1088/0268-1242/29/2/023002
Abstract: This review aims to introduce the x-ray emission spectroscopy (XES) and resonant inelastic x-ray scattering (RIXS) techniques to the materials scientist working with magnetic semiconductors (e.g. semiconductors doped with 3d transition metals) for applications in the field of spin-electronics. We focus our attention on the hard part of the x-ray spectrum (above 3 keV) in order to demonstrate a powerful element- and orbital-selective characterization tool in the study of bulk electronic structure. XES and RIXS are photon-in/photon-out second order optical processes described by the Kramers-Heisenberg formula. Nowadays, the availability of third generation synchrotron radiation sources permits applying such techniques also to dilute materials, opening the way for a detailed atomic characterization of impurity-driven materials. We present the K{\beta} XES as a tool to study the occupied valence states (directly, via valence-to-core transitions) and to probe the local spin angular momentum (indirectly, via intra-atomic exchange interaction). The spin sensitivity is employed, in turn, to study the spin-polarized unoccupied states. Finally, the combination of RIXS with magnetic circular dichroism (RIXS-MCD) extends the possibilities of standard magnetic characterization tools.
Translational research in acupuncture—teleacupuncture bridges science and practice  [PDF]
Gerhard Litscher
Health (Health) , 2010, DOI: 10.4236/health.2010.21003
Abstract: In March 2009, the first teleacupuncture between China and Austria was performed. This publica-tion summarizes the first important results. 24- hour electrocardiograms were registered in Bei-jing and analyzed in Graz. A heart rate variability monitor partly developed in Austria was used for recording. Data were transferred via internet over a distance of 7,650 km. For the spectral analysis of heart rate variability a new method, the so-called ‘Fire of Life’ illustration, was ap-plied. The state of health of a 31-year-old patient before, during and after acupuncture treatment sessions was documented. Despite several limi- tations, transcontinental teleacupuncture opens up new possibilities in public health.
Oscillating Universe  [PDF]
Gerhard Lessner
Journal of Modern Physics (JMP) , 2011, DOI: 10.4236/jmp.2011.210135
Abstract: It is pointed out that the inflationary flat Λ-CDM-model coming out from a big bang seems to be inconsistent. An alternative model based on previous work by the author is outlined. It starts with a geometrical phase transition in Minkowski space where the source of the gravitational field is a Higgs-like scalar field φ. After the phase transition space-time is a contracting anti-deSitter space. Matter and radiation are created over a very long period of about 30 billion years from the gravitational energy. About 44 billion years after the phase transition the universe runs through a nonsingular minimum.
Foucault’s Concept of Heterotopia as an èpistemé for Reading the Post-Modern City: The Viennese Example  [PDF]
Gerhard Hatz
Current Urban Studies (CUS) , 2018, DOI: 10.4236/cus.2018.64025
Abstract:
“The postmodern city is a myth, a tale, a telling, a poignant narrative that builds on the past to continually new horizons… The postmodern city is not only an epitomizing model of contemporary social and economic development, but also a metaphysical reality, a place where the real and the imagined are persistently commingled in ways we have only begun to understand…” (Chambers, 1990; Soja 2000). Normative notions on the city have to be dissected as an intersection of the near and the far order of urban societies (Lefebvre, 1996) and as fluid conceptualizations in a heterochronical context. However, cities similarly have to be read as “thirdspaces” (Soja, 1996)—contestations of mythical and real urban spaces and places, continuously re-interpreted and endowing urban spaces and places with even transient meanings. The paper seeks to grasp Foucault’s notions on heterotopia as a theoretical framework and èpistemé for approaching these “thirdspaces”—in-between the social relations and their inscriptions into the material reality of cities.
Small scale spatial heterogeneity of soil respiration in an old growth temperate deciduous forest
A. Jordan,G. Jurasinski,S. Glatzel
Biogeosciences Discussions , 2009,
Abstract: The large scale spatial heterogeneity of soil respiration caused by differences in site conditions is quite well understood. However, comparably little is known about the micro scale heterogeneity within forest ecosystems on homogeneous soils. Forest age, soil texture, topographic position, micro topography and stand structure may influence soil respiration considerably within short distance. In the present study within site spatial heterogeneity of soil respiration has been evaluated. To do so, an improvement of available techniques for interpolating soil respiration data via kriging was undertaken. Soil respiration was measured with closed chambers biweekly from April 2005 to April 2006 using a nested design (a set of stratified random plots, supplemented by 2 small and 2 large nested groupings) in an unmanaged, beech dominated old growth forest in Central Germany (Hainich, Thuringia). A second exclusive randomized design was established in August 2005 and continually sampled biweekly until July 2007. The average soil respiration values from the random plots were standardized by modeling soil respiration data at defined soil temperature and soil moisture values. By comparing sampling points as well as by comparing kriging results based on various sampling point densities, we found that the exclusion of local outliers was of great importance for the reliability of the estimated fluxes. Most of this information would have been missed without the nested groupings. The extrapolation results slightly improved when additional parameters like soil temperature and soil moisture were included in the extrapolation procedure. Semivariograms solely calculated from soil respiration data show a broad variety of autocorrelation distances (ranges) from a few centimeters up to a few tens of meters. The combination of randomly distributed plots with nested groupings plus the inclusion of additional relevant parameters like soil temperature and soil moisture data permits an improved estimation of the range of soil respiration, which is a prerequisite for reliable interpolated maps of soil respiration.
Winter emissions of carbon dioxide, methane and nitrous oxide from a minerotrophic fen under nature conservation management in north-east Germany
V. Huth,G. Jurasinski,S. Glatzel
Mires and Peat , 2012,
Abstract: Drained peatlands are known to be important sources of carbon dioxide (CO2) and nitrous oxide (N2O). While CO2 emissions occur mainly during the growing season, large N2O emissions may occur during the non-growing season as well. Peatland re-wetting may be an effective measure to prevent those emissions. However, recent research shows that re-wetted peatlands may release large amounts of methane (CH4) during the years immediately after re-wetting whereas abandonment of intensive grassland on drained peat soils possibly leads to low nutrient supply and thus to small greenhouse gas (GHG) emissions. Here we examine the role of extensification practices (such as abandonment of mineral fertilisation, reduced cutting frequency and a cattle-free winter period) on GHG emissions from a temperate peatland during winter. From November 2009 to March 2010 GHG measurements were made on a minerotrophic fen five years after intensive grassland use was abandoned. During the measurement period CO2 and N2O emissions amounted to 4.4 t ha-1 and 2.6 t ha-1 CO2-equivalent, whilst CH4 emissions were negligible. Altogether the site emitted 7 t ha-1 CO2-equivalent, of which 37 % was N2O, even though the winter 2009/2010 was extraordinarily cold. Thus, extensification of grassland use alone may not be sufficient to reduce GHG emissions from temperate peatlands.
Non-linear pulsations in Wolf-Rayet stars
S. Wende,W. Glatzel,S. Schuh
Physics , 2009,
Abstract: Numerical simulations of the evolution of strange-mode instabilities into the non-linear regime have been performed for a wide range of stellar parameters for Wolf-Rayet stars. It has been shown that the Wolf-Rayet models reach radial velocities which amount to up to 30% of their escape velocity. The acoustic luminosities suggest a connection to the observed mass loss. Most of the models show a jump in the mean effective temperature after reaching the non-linear regime. This jump is related to the run of the opacity.
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