bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organizational identity strength, identification, and commitment and their relationships to turnover intention: does organizational hierarchy matter?
Authors: Cole Michael S. , Bruch Heike 
Published: June 2006

AbstractIn the present study we sought to clarify the functional distinctions between organization identity strength, organizational identification, and organizational commitment. Data were obtained from 10 948 employees of a large steel manufacturer. First, confirmatory factor analysis was used to test the discriminant validity of the three focal constructs. Next, drawing on research that suggests hierarchical differentiation may influence individuals' conceptual frame of reference, we examined each focal construct's measurement equivalence across three hierarchical levels (officers, n = 1,056, middle‐management, n = 1049, workers, n = 1050). Finally, multigroup structural equation modeling was used to simultaneously estimate the between‐group correlations between turnover intention and organization identity strength, organizational identification, and organizational commitment. Results indicated that (a) the measures used to reflect the three focal constructs were empirically distinct, (b) the focal constructs were conceptually equivalent across hierarchical levels, and (c) the pattern of correlations with turnover intention was different for employees with management responsibilities versus workers with no management responsibility. The present findings suggest perceptions of a strong organizational identity, organizational identification, and organizational commitment may influence employees' turnover intention in unique ways, depending on their hierarchical level within the organization. Copyright © 2006 John Wiley & Sons, Ltd.
Social identities and commitments at work: toward an integrative model
Authors: Meyer John P. , Becker Thomas E. , van Dick Rolf 
Published: June 2006

AbstractAlthough social identities and work‐related commitment are important aspects of employee attachment, distinctions between and relations among the two have not been clearly articulated. In this conceptual piece, we propose that identity and commitment are distinguishable in terms of their essential meaning, foci of attachment, mindsets, volitionality, and behavioral implications. We further suggest that situated and deep structure social identities are differentially antecedent to exchange‐based and value‐based commitments, and that commitment mediates, at least partially, the effects of identities on motivation and work behavior. Finally, we consider the implications of multiple identities for employees in different kinds of collectives (nested and cross‐cutting). Copyright © 2006 John Wiley & Sons, Ltd.
Modeling ferricyanide adsorption on goethite: Basics and applications
Authors: Rennert Thilo , Mansfeldt Tim 
Published: June 2006

AbstractFerricyanide, [FeIII(CN)6]3–, is an anthropogenic and potentially toxic contaminant in soil. Its adsorption on goethite has been previously studied, but not evaluated with a surface complexation model (SCM) considering the effects of pH and ionic strength. Therefore, we carried out batch experiments with ferricyanide and goethite suspensions with different ferricyanide concentrations (0.075 mM and 0.15 mM), ionic strengths (0.01 and 0.1 M), and pH (ranging from 4 to 7.4). Adsorption data were then interpreted with the 1‐pK Stern and the charge distribution model assuming monodentate inner‐sphere ferricyanide surface complexes on goethite (lg K = 10.6), which are known from infrared spectroscopy. Furthermore, we applied the SCM to ferricyanide adsorption in previous studies on ferricyanide adsorption in the presence of sulfate and on the solubility of Fe‐cyanide complexes in a suspension of a loess loam. The SCM correctly reflected ferricyanide adsorption in the batch experiments as well as the effects of pH and ionic strength. The SCM also described ferricyanide adsorption in the presence of sulfate, because the ferricyanide adsorption measured and that modeled were significantly correlated (R2 = 0.80). Furthermore, we applied the SCM to a study on the solubility of Fe‐cyanide complexes in soil under varying redox conditions so that ferricyanide adsorption on goethite and precipitation of Fe‐cyanide complexes were considered. The actual ferricyanide concentrations were rather reflected when applying the SCM compared to those modeled in an approach in which exclusively precipitation was taken into account. We conclude that ferricyanide adsorption on goethite should be included into geochemical modeling approaches on the mobility of Fe‐cyanide complexes in subsoils.
Black carbon in the zonal steppe soils of Russia
Authors: Rodionov Andrej , Amelung Wulf , Haumaier Ludwig , Urusevskaja Inga , Zech Wolfgang 
Published: June 2006

AbstractBlack Mollisols are typically rich in charred organic matter, however, little is known about the zonal distribution of black C (BC) in steppe soils. In this study, we used benzene polycarboxylic acids (BPCA) as specific markers for BC in particle‐size fractions of depth profiles in several zonal soils (Greyzem, Phaeozem, Chernozem, Kastanozem) of the Russian steppe. In addition, liquid‐state 13C‐NMR spectra were obtained on the alkaline‐soluble soil organic matter (SOM). The results showed that both the content and depth distribution of BC varies in the different soil types; the concentration of BC in the bulk top soils being closely related to the aromaticity of the SOM (r2 = 0.98 for the native topsoils, 0.83 for top‐ and subsurface soils). Especially the Chernozems were rich in aromatic SOM, which partly contained more than 17% BC of total C, most of which being allocated in the mineral fractions. Long‐term arable cropping did not reduce the BC contents of the surface soil, though it did promote the enrichment of BC in the silt fractions. The same shift was detected as soil depth increased. We conclude that BC is not fully inert in these soils, but apparently can be preserved in the silt as decomposition of SOM increased, i.e., it accumulates exactly in that fraction, which has been formerly assigned to contain old, aromatic C.
Soil mapping for land‐use planning in a karst area of N Thailand with due consideration of local knowledge
Authors: Schuler Ulrich , Choocharoen Chalathon , Elstner Peter , Neef Andreas , Stahr Karl , Zarei Mehdi , Herrmann Ludger 
Published: June 2006

AbstractFor the development of sustainable land‐management systems in the highlands of N Thailand, detailed knowledge about soil distribution and soil properties is a prerequisite. Yet to date, there are hardly any detailed soil maps available on a watershed scale.In this study, soil maps on watershed level were evaluated with regard to their suitability for agricultural land‐use planning. In addition to common scientific methods (as underlying the WRB classification), participatory methods were used to exploit local knowledge about soils and to document it in a “Local Soil Map”.Where the WRB classification identified eight soil units, the farmers distinguished only five on the basis of soil color and “hardness”. The “Local Soil Map” shows little resemblance with the detailed, patchy pattern of the WRB‐based soil map. On the contrary, the “Local Soil Map” is fairly similar to the petrographic map suggesting that soil color is directly related to parent material.The farmers' perception about soil fertility and soil suitability for cropping could be confirmed by analytical data. We conclude that integrating local soil knowledge, petrographic information, and knowledge of local cropping practices allows for a rapid compilation of information for land‐evaluation purposes at watershed level. It is the most efficient way to build a base for regional land‐use planning.
Rheological‐stiffness analysis of K+‐treated and CaCO3‐rich soils
Authors: Markgraf Wibke , Horn Rainer 
Published: June 2006

AbstractRheological methods are applied whenever flow behavior of substances needs to be investigated on a particle‐to‐particle scale executed by a parallel‐plate rheometer. Under oscillation, mechanical effects due to trafficking or vibrations caused by agricultural and forest machinery can be simulated by conducting amplitude‐sweep tests. Hooke's law of elasticity, Newton's law for ideal fluids (viscosity), Mohr‐Coulomb's equation, and, finally, Bingham's yielding are well‐known relationships and parameters in the field of rheology. This paper aims to introduce rheometry as a suitable method to determine the mechanical behavior of salt‐affected soils when subjected to external stresses. Potassium‐treated loamy sand from Halle and loamy silt from Kassel, both sites located in Germany, as well as loess from Israel, saturated with NaCl solutions in several concentrations were analyzed. From the stress‐strain–relationship parameters like the storage modulus G′ and the loss modulus G″, yield stress τy and the linear viscoelastic (LVE)–deformation range including the deformation limit γL, i.e., the transition from an elastic to a viscous state, were determined and calculated, respectively. With respect to salt effects, amplitude‐sweep tests on originally CaCO3‐rich Avdat Loess show an increasing stability if saturated with higher NaCl concentrations. Comparable tests with K+‐rich substrates from Halle and Kassel evinced similar tendencies including the phenomenon of a critical K+ content, which becomes more obvious in case of the drained (–60h Pa) loamy‐silt samples from Kassel. Nevertheless, a higher microstructural stability is given in both substrates from Halle and Kassel, affected by different water contents, in general, which influence the exchange and availability of cations. The results verify that oscillatory tests are applicable for retracing salt‐induced effects, beside those ones, which are influenced by texture, current water content, and/or further chemical parameters.
Methods for evaluating human impact on soil microorganisms based on their activity, biomass, and diversity in agricultural soils
Authors: Joergensen Rainer Georg , Emmerling Christoph 
Published: June 2006

AbstractThe present review is focused on microbiological methods used in agricultural soils accustomed to human disturbance. Recent developments in soil biology are analyzed with the aim of highlighting gaps in knowledge, unsolved research questions, and controversial results. Activity rates (basal respiration, N mineralization) and biomass are used as overall indices for assessing microbial functions in soil and can be supplemented by biomass ratios (C : N, C : P, and C : S) and eco‐physiological ratios (soil organic C : microbial‐biomass C, qCO2, qNmin). The community structure can be characterized by functional groups of the soil microbial biomass such as fungi and bacteria, Gram‐negative and Gram‐positive bacteria, or by biotic diversity. Methodological aspects of soil microbial indices are assessed, such as sampling, pretreatment of samples, and conversion factors of data into biomass values. Microbial‐biomass C (µg (g soil)–1) can be estimated by multiplying total PLFA (nmol (g soil)–1) by the FPLFA‐factor of 5.8 and DNA (µg (g soil)–1) by the FDNA‐factor of 6.0. In addition, the turnover of the soil microbial biomass is appreciated as a key process for maintaining nutrient cycles in soil. Examples are briefly presented that show the direction of human impact on soil microorganisms by the methods evaluated. These examples are taken from research on organic farming, reduced tillage, de‐intensification of land‐use management, degradation of peatland, slurry application, salinization, heavy‐metal contamination, lignite deposition, pesticide application, antibiotics, TNT, and genetically modified plants.
The mechanical behavior of structured and homogenized soil under repeated loading
Authors: Peth Stephan , Horn Rainer 
Published: June 2006

AbstractSoil deformation is increasingly important in crop production since nowadays weights of agricultural machines exceed the bearing capacity of most soils. Often this is counteracted by distributing the weight over more axles leading to an increase in wheeling frequency. Machine passages during one year can, depending on the crop and equipment used, range between two and five times for the majority of the field and up to twenty times and more for a wheeling track. These add up to hundreds of loading events for a crop‐rotation period. In this study, we investigated the effect of multiple loading with the same load in a cyclic‐compression test on soil‐pore‐volume change. The tests were conducted on homogenized soil samples with varying texture and undisturbed soil samples from a field experimental site comparing conventional and conservation‐tillage systems. Of particular interest was the question whether there is significant plastic soil deformation for soil stresses that remained sufficiently below the precompression stress, which is commonly neglected. Our results show that especially for cohesive soils, the assumption of fully elasticity in the recompression range may not be justified since those soils show distinct cyclic‐creep behavior. We found that deformation under cyclic loading follows a logarithmic law. We used the slope of the logarithmic fit of void‐ratio changes vs. loading cycles as a parameter to characterize the sensitivity of soils to cyclic compression. The results suggest that for characterizing the mechanical stability of soils that show cyclic creep, we have (with respect to long‐term deformation effects) to consider both precompression stress and cyclic compressibility.
Topsoil characterization—recommendations for revision and expansion of the FAO‐Draft (1998) with emphasis on humus forms and biological features
Authors: Broll Gabriele , Brauckmann Hans‐Jörg , Overesch Mark , Junge Birte , Erber Claudia , Milbert Gerhard , Baize Denis , Nachtergaele Freddy 
Published: June 2006

AbstractThe characterization of topsoils has recently received enhanced attention, particularly for environmental monitoring. Traditional national and international soil taxonomies hardly consider the topsoil in spite of its importance for soil quality. Consequently, the FAO “Topsoil Characterization for Sustainable Land Management” was developed to be used additionally for describing topsoils and to combine it with the “World Reference Base for Soil Resources” (WRB). In this paper, recommendations for a first step of a revision and expansion of the FAO “Topsoil Characterization” are made. On the one hand, common rules for soil description as used in the FAO “Guidelines for Profile Description” were incorporated in the FAO “Topsoil Characterization”. On the other hand, new characteristics for the description of the organic matter and of biological features of the topsoils were introduced. At first, the proposed German systematics of humus forms is presented and correlated with different national systematics, for validation in the international context. Secondly, a correlation of the new German systematics of humus forms with the FAO “Topsoil Characterization for Sustainable Land Management” and other topsoil systematics is made. Thirdly, additional qualifiers are described focussing on the organic layers and the biological features.A coincidence between the characterization of humus forms and topsoils was found which appears to be an appropriate basis for the incorporation of humus forms in the FAO “Topsoil Characterization”. Investigations have shown that the topsoils in forests can be described comprehensively by additional qualifiers for the organic layers. Grassland or arable land which usually lack organic layers can be characterized in detail by qualifiers concerning soil biological activity in the A horizon. The methodology was already applied successfully in temperate regions. But there is still a need for further discussion of the revision and for tests in tropical and subtropical zones and poorly drained areas.
Silicon pools and fluxes in soils and landscapes—a review
Authors: Sommer Michael , Kaczorek Danuta , Kuzyakov Yakov , Breuer Jörn 
Published: June 2006

AbstractSilicon (Si) is the second‐most abundant element in the earth's crust. In the pedosphere, however, huge spans of Si contents occur mainly caused by Si redistribution in soil profiles and landscapes. Here, we summarize the current knowledge on the different pools and fluxes of Si in soils and terrestrial biogeosystems. Weathering and subsequent release of soluble Si may lead to (1) secondarily bound Si in newly formed Al silicates, (2) amorphous silica precipitation on surfaces of other minerals, (3) plant uptake, formation of phytogenic Si, and subsequent retranslocation to soils, (4) translocation within soil profiles and formation of new horizons, or (5) translocation out of soils (desilication). The research carried out hitherto focused on the participation of Si in weathering processes, especially in clay neoformation, buffering mechanisms for acids in soils or chemical denudation of landscapes. There are, however, only few investigations on the characteristics and controls of the low‐crystalline, almost pure silica compounds formed during pedogenesis. Further, there is strong demand to improve the knowledge of (micro)biological and rhizosphere processes contributing to Si mobilization, plant uptake, and formation of phytogenic Si in plants, and release due to microbial decomposition. The contribution of the biogenic Si sources to Si redistribution within soil profiles and desilication remains unknown concerning the pools, rates, processes, and driving forces. Comprehensive studies considering soil hydrological, chemical, and biological processes as well as their interactions at the scale of pedons and landscapes are necessary to make up and model the Si balance and to couple terrestrial processes with Si cycle of limnic, fluvial, or marine biogeosystems.
Problems in CEC determination of calcareous clayey sediments using the ammonium acetate method
Authors: Dohrmann Reiner 
Published: June 2006

AbstractCation‐exchange–capacity (CEC) results of calcareous soils and clays can be erroneous if the ammonium acetate method is used. In this study, a model is proposed to explain the process for systematic underestimation of the CEC. Seven clayey sediments from Germany with varying calcite and low organic‐C content were studied. After several exchange treatments with concentrated ammonium acetate (NH4Ac) solutions, the exchange population is assumed to be in homoionic ammonium form. Throughout the cation‐exchange experiment, calcite reacts with the NH4Ac exchange solution generating Ca2+ cations. During the necessary washing steps to remove excess salt, calcite dissolution is lower but still occurs. The permanently added Ca2+ ions compete successfully with NH$ _4^+ $, especially during the washing steps. This leads to a more or less partial biionic exchange population resulting in an underestimation of the CEC which is calculated based on NH$ _4^+ $ concentration of the clay by Kjeldahl analysis. The biionic exchange population was proven using the new silver thiourea technique with presaturation of calcite, AgTUcalcite. The clay with 148 g kg–1 calcite had a fraction of 16.4 cmol+ kg–1 exchangeable Ca2+. This is ca. 50% of the CEC of this clay being 31.8 cmol+ kg–1. For clays with similar mineralogical composition, this trend is proportional to the calcite content.
Ordered Microporous Surface Films Formed by Core‐Shell‐Type Nanospheres
Authors: Ishizu Koji , Kobayakawa Naoyuki , Uchida Satoshi 
Published: June 2006

AbstractSummary: Polymer nanospheres are synthesized by free‐radical dispersion copolymerization of methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDM) with a methacryloyl‐terminated polystyrene (PS‐MC) macromonomer in cyclohexane. Such polymer nanospheres are stabilized sterically with polystyrene (PS)‐grafted chains in cyclohexane at temperatures greater than 34 °C (the Θ temperature for PS). Ordered microporous surface films are constructed by casting these core‐shell‐type nanospheres from hot cyclohexane solution at 20 °C. The results indicate the possibility of fixation or encapsulation of functional materials after microporous patterning of the core‐shell‐type nanospheres.SEM photograph of a vertical section of a hexagonal micropore film obtained here.magnified imageSEM photograph of a vertical section of a hexagonal micropore film obtained here.
Time dependence of 3He diffusion in the human lung: Measurement in the long‐time regime using stimulated echoes
Authors: Wang Chengbo , Miller G. Wilson , Altes Talissa A. , de Lange Eduard E. , Cates Jr. Gordon D. , Mugler John P. 
Published: June 2006

AbstractA stimulated‐echo‐based technique was developed to measure the long‐time‐scale apparent diffusion coefficient (ADC) of hyperpolarized 3He during a single breath‐hold acquisition. Computer simulations were used to evaluate the performance of the technique and guide the selection of appropriate parameter values for obtaining accurate ADC values. The technique was used in 10 healthy subjects and two subjects with chronic obstructive pulmonary disease (COPD) to measure the global ADC for diffusion times between a few tenths of a second and several seconds, and to acquire spatial maps of the ADC for a diffusion time of 1.5 s. The reproducibility of the technique and its sensitivity to the direction of diffusion sensitization were also investigated. In healthy subjects, global ADC values decreased by severalfold over the range of diffusion times measured (mean values = 0.039 and 0.023 cm2/s at diffusion times of 0.61 and 1.54 s, respectively). ADC maps were generally uniform, with mean values similar to the corresponding global values. For the two COPD subjects, global ADC values were substantially greater than those of every healthy subject at all diffusion times measured. In addition, regional elevations of ADC values were far more conspicuous on long‐time‐scale ADC maps than on short‐time‐scale ADC maps. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Limits on activation‐induced temperature and metabolic changes in the human primary visual cortex
Authors: Katz‐Brull Rachel , Alsop David C. , Marquis Robert P. , Lenkinski Robert E. 
Published: June 2006

AbstractChanges in cerebral blood flow (CBF) and metabolism are now widely used to map and quantify neural activity, although the underlying mechanism for these changes is still incompletely understood. Magnetic resonance spectroscopy (MRS) at 3T, synchronized with a 32‐s block design visual stimulation paradigm, was employed to investigate activation‐induced changes in temperature and metabolism in the human primary visual cortex. A marginally significant increase in the local temperature of the visual cortex was found (0.1°C, P = 0.09), excluding the possibility of a temperature decrease (95% confidence interval (CI) = 0.0–0.2°C), which was previously suggested. A comparison with models of thermal equilibrium in the presence of blood flow suggests that an increase in heat production during activation, greater than or at least equal to that produced by the complete oxidative metabolism of the elevated glucose (Glc) utilization accompanying activation, would be required to offset the cooling effects of the increased blood flow. The total pools of glutamate (Glu), glutamine (Gln), myo‐Inositol (mI), N‐acetylaspartate (NAA), choline (Cho), and lactate (Lac) were not significantly affected by activation. Limits on Lac concentration changes were too weak to constrain theories of the metabolic use of elevated Glc consumption during stimulation, and emphasize the challenges of measuring even large Lac changes accompanying stimulation. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Pharmakologie der Diuretika: Angriffspunkte der verschiedenen Wirkstoffgruppen
Authors: Knauf Heinrich , Mutschler Ernst 
Published: June 2006

AbstractDiuretika als harntreibende Arzneistoffe wurden zunächst klinisch‐pharmakologisch nach dem Ausmaß der Diuresesteigerung und der Dosis‐Abhängigkeit ihrer Wirkung eingeteilt. Demgemäß unterschied man High‐ceiling‐von Low‐ceiling‐Diuretika, wobei der Begriff Ceiling (“Decke”) pharmakologisch die maximal erreichbare Wirkstärke (intrinsische Aktivität) des Arzneistoffes charakterisiert.