Showing papers by "University of Stuttgart published in 2001"
TL;DR: This article considers the empirical data and then reviews the main approaches to modeling pedestrian and vehicle traffic, including microscopic (particle-based), mesoscopic (gas-kinetic), and macroscopic (fluid-dynamic) models.
Abstract: Since the subject of traffic dynamics has captured the interest of physicists, many surprising effects have been revealed and explained. Some of the questions now understood are the following: Why are vehicles sometimes stopped by ``phantom traffic jams'' even though drivers all like to drive fast? What are the mechanisms behind stop-and-go traffic? Why are there several different kinds of congestion, and how are they related? Why do most traffic jams occur considerably before the road capacity is reached? Can a temporary reduction in the volume of traffic cause a lasting traffic jam? Under which conditions can speed limits speed up traffic? Why do pedestrians moving in opposite directions normally organize into lanes, while similar systems ``freeze by heating''? All of these questions have been answered by applying and extending methods from statistical physics and nonlinear dynamics to self-driven many-particle systems. This article considers the empirical data and then reviews the main approaches to modeling pedestrian and vehicle traffic. These include microscopic (particle-based), mesoscopic (gas-kinetic), and macroscopic (fluid-dynamic) models. Attention is also paid to the formulation of a micro-macro link, to aspects of universality, and to other unifying concepts, such as a general modeling framework for self-driven many-particle systems, including spin systems. While the primary focus is upon vehicle and pedestrian traffic, applications to biological or socio-economic systems such as bacterial colonies, flocks of birds, panics, and stock market dynamics are touched upon as well.
3,117 citations
TL;DR: Several (laboratory-scale) continuous anaerobic/aerobic processes for the treatment of wastewaters containing azo dyes have recently been described.
Abstract: Azo dyes are the most important group of synthetic colorants. They are generally considered as xenobiotic compounds that are very recalcitrant against biodegradative processes. Nevertheless, during the last few years it has been demonstrated that several microorganisms are able, under certain environmental conditions, to transform azo dyes to non-colored products or even to completely mineralize them. Thus, various lignolytic fungi were shown to decolorize azo dyes using ligninases, manganese peroxidases or laccases. For some model dyes, the degradative pathways have been investigated and a true mineralization to carbon dioxide has been shown. The bacterial metabolism of azo dyes is initiated in most cases by a reductive cleavage of the azo bond, which results in the formation of (usually colorless) amines. These reductive processes have been described for some aerobic bacteria, which can grow with (rather simple) azo compounds. These specifically adapted microorganisms synthesize true azoreductases, which reductively cleave the azo group in the presence of molecular oxygen. Much more common is the reductive cleavage of azo dyes under anaerobic conditions. These reactions usually occur with rather low specific activities but are extremely unspecific with regard to the organisms involved and the dyes converted. In these unspecific anaerobic processes, low-molecular weight redox mediators (e.g. flavins or quinones) which are enzymatically reduced by the cells (or chemically by bulk reductants in the environment) are very often involved. These reduced mediator compounds reduce the azo group in a purely chemical reaction. The (sulfonated) amines that are formed in the course of these reactions may be degraded aerobically. Therefore, several (laboratory-scale) continuous anaerobic/aerobic processes for the treatment of wastewaters containing azo dyes have recently been described.
1,119 citations
TL;DR: In this article, an overview of the membrane development for proton-conductive polymer (composite) membranes for the application membrane fuel cells, focusing on the membrane developments in this field performed at ICVT.
1,006 citations
TL;DR: CFLIP expression was able to reverse the proapoptotic effect of NF-κB inhibition, and Western blot analysis revealed that cFLIP, but not TRAF1, A20, and cIAP2, expression levels rapidly decrease upon CHX treatment.
Abstract: The caspase 8 homologue FLICE-inhibitory protein (cFLIP) is a potent negative regulator of death receptor-induced apoptosis We found that cFLIP can be upregulated in some cell lines under critical involvement of the NF-κB pathway, but NF-κB activation was clearly not sufficient for cFLIP induction in all cell lines Treatment of SV80 cells with the proteasome inhibitor N-benzoyloxycarbonyl (Z)-Leu-Leu-leucinal (MG-132) or geldanamycin, a drug interfering with tumor necrosis factor (TNF)-induced NF-κB activation, inhibited TNF-induced upregulation of cFLIP Overexpression of a nondegradable IκBα mutant (IκBα-SR) or lack of IκB kinase γ expression completely prevented phorbol myristate acetate-induced upregulation of cFLIP mRNA in Jurkat cells These data point to an important role for NF-κB in the regulation of the cFLIP gene SV80 cells normally show resistance to TNF-related apoptosis-inducing ligand (TRAIL) and TNF, as apoptosis can be induced only in the presence of low concentrations of cycloheximide (CHX) However, overexpression of IκBα-SR rendered SV80 cells sensitive to TRAIL-induced apoptosis in the absence of CHX, and cFLIP expression was able to reverse the proapoptotic effect of NF-κB inhibition Western blot analysis further revealed that cFLIP, but not TRAF1, A20, and cIAP2, expression levels rapidly decrease upon CHX treatment In conclusion, these data suggest a key role for cFLIP in the antiapoptotic response of NF-κB activation
634 citations
01 Aug 2001
TL;DR: A novel texture-based volume rendering approach that achieves the image quality of the best post-shading approaches with far less slices, suitable for new flexible consumer graphics hardware and suited for interactive high-quality volume graphics.
Abstract: We introduce a novel texture-based volume rendering approach that achieves the image quality of the best post-shading approaches with far less slices. It is suitable for new flexible consumer graphics hardware and provides high image quality even for low-resolution volume data and non-linear transfer functions with high frequencies, without the performance overhead caused by rendering additional interpolated slices. This is especially useful for volumetric effects in computer games and professional scientific volume visualization, which heavily depend on memory bandwidth and rasterization power.We present an implementation of the algorithm on current programmable consumer graphics hardware using multi-textures with advanced texture fetch and pixel shading operations. We implemented direct volume rendering, volume shading, arbitrary number of isosurfaces, and mixed mode rendering. The performance does neither depend on the number of isosurfaces nor the definition of the transfer functions, and is therefore suited for interactive high-quality volume graphics.
590 citations
TL;DR: In this Minireview examples of newer stoichiometric and catalytic methods are summarized which have proved their suitability for the enantioselective construction of quaternary stereocenters.
Abstract: The stereoselective formation of C-C bonds is of great importance for the synthesis of enantiomerically pure natural products and pharmaceuticals. A broad repertoire of chiral auxiliaries, reagents, and catalysts can be utilized for the reliable generation of tertiary stereocenters. In contrast, the synthesis of organic compounds with quaternary stereocenters is a much more demanding and challenging task. Every enantioselective synthetic method can demonstrate its value through the generation of a fully substituted carbon center. In this Minireview examples of newer stoichiometric and catalytic methods are summarized which have proved their suitability for the enantioselective construction of quaternary stereocenters.
561 citations
Book•
01 Jan 2001TL;DR: The emphasis shifts from FORTRAN to C++, in recognition of the upsurge of object oriented programming in engineering simulations, and the CADAC4 software package provides eight C++ simulations, which range from UAVs, aircraft, missiles, and boosters to hypersonic aircraft with transfer vehicles for satellite rendezvous.
Abstract: Overview Mathematical Concepts in Modeling Frames and Coordinate Systems Kinematics of Translation and Rotation Quatrenions Translational Dynamics Attitude Dynamics Perturbation Equations of Steady and Unsteady Flight Three-Degree-of-Freedom Simulation Turbo-Ramjet Propulsion Five-Degree-of-Freedom Simulation Proportional Navigation Gimbaled Seekers GPS Six-Degree-of-Freedom Simulation Oblate Earth Model Aerodynamic Modeling Autopilots INS Modeling Monte Carlo Analysis Turbulence Modeling Cockpit Simulators Hardware-In-The-Loop Facilities Wargaming Real-Time Applications Appendix A: Matrices Appendix B: CADAC Primer Appendix C. Aerospace Simulations in C++ Appendix D. Analytical Foundation of Tensor Flight Dynamics.
476 citations
TL;DR: Flow cytometric analysis revealed reduced damage with respect to cytoplasmic membrane potential and integrity in cells grown in the dynamic environments of the large scale reactor and the scale-down reactor.
443 citations
TL;DR: The TNF-receptor-associated factor (TRAF) family is a phylogenetically conserved group of scaffold proteins that link receptors of the IL-1R/Toll and TNF receptor family to signalling cascades, leading to the activation of NF-κB and mitogen-activated protein kinases as discussed by the authors.
366 citations
TL;DR: This work demonstrates the applicability of correspondence analysis to and high value for the analysis of microarray data, displaying associations between genes and experiments and applies it to a non-time-series data set of its own.
Abstract: Correspondence analysis is an explorative computational method for the study of associations between variables. Much like principal component analysis, it displays a low-dimensional projection of the data, e.g., into a plane. It does this, though, for two variables simultaneously, thus revealing associations between them. Here, we demonstrate the applicability of correspondence analysis to and high value for the analysis of microarray data, displaying associations between genes and experiments. To introduce the method, we show its application to the well-known Saccharomyces cerevisiae cell-cycle synchronization data by Spellman et al. [Spellman, P. T., Sherlock, G., Zhang, M. Q., Iyer, V. R., Anders, K., Eisen, M. B., Brown, P. O., Botstein, D. & Futcher, B. (1998) Mol. Biol. Cell 9, 3273-3297], allowing for comparison with their visualization of this data set. Furthermore, we apply correspondence analysis to a non-time-series data set of our own, thus supporting its general applicability to microarray data of different complexity, underlying structure, and experimental strategy (both two-channel fluorescence-tag and radioactive labeling).
350 citations
TL;DR: It is pointed out that saturation transients are indispensable for a proper description of sand flux over structured terrain, by applying the model to the windward side of an isolated dune, thereby resolving recently reported discrepancies between field measurements and theoretical predictions.
Abstract: We derive a phenomenological continuum saltation model for aeolian sand transport that can serve as an efficient tool for geomorphological applications. The coupled differential equations for the average density and velocity of sand in the saltation layer reproduce both the known equilibrium relations for the sand flux and the time evolution of the sand flux as predicted by microscopic saltation models. The three phenomenological parameters of the model are a reference height for the grain-air interaction, an effective restitution coefficient for the grain-bed interaction, and a multiplication factor characterizing the chain reaction caused by the impacts leading to a typical time or length scale of the saturation transients. We determine the values of these parameters by comparing our model with wind tunnel measurements. Our main interest are out of equilibrium situations where saturation transients are important, for instance at phase boundaries (ground/sand) or under unsteady wind conditions. We point out that saturation transients are indispensable for a proper description of sand flux over structured terrain, by applying the model to the windward side of an isolated dune, thereby resolving recently reported discrepancies between field measurements and theoretical predictions.
TL;DR: In this paper, molecular models for 25 pure fluids are presented based on the two-center Lennard-Jones plus point quadrupole pair potential (2CLJQ) and the model parameters were adjusted to experimental vapor−liquid equilibria of the pure fluids using a highly efficient procedure.
Abstract: Molecular models for 25 different pure fluids are presented: neon, argon, krypton, xenon, methane, oxygen, nitrogen, fluorine, chlorine, bromine, iodine, carbon dioxide, carbon disulfide, ethane, ethene, ethyne, perfluoroethane, perfluoroethene, perchloroethene, propadiene, propyne, sulfurhexafluoride, tetrafluoromethane, tetrachloromethane, and propylene. The models are based on the two-center Lennard-Jones plus pointquadrupole pair potential (2CLJQ). The model parameters were adjusted to experimental vapor−liquid equilibria of the pure fluids using a highly efficient procedure. The application of these models to the calculation of vapor−liquid equilibria and homogeneous fluid state points by molecular simulation shows good agreement with experimental results. Numbers for model parameters correlate reasonably with geometric data of the molecules and experimental quadrupole moments. Due to the compatibility of the presented models, applications to the prediction of vapor−liquid equilibria of mixtures are...
TL;DR: A gas chromatography/mass spectrometry method for the simultaneous quantitative determination of natural and synthetic estrogens and phytoestrogens in effluents of sewage treatment plants (STPs) was developed and selected substances were detected in the majority of samples.
Abstract: The proliferation test with human estrogen receptor-positive MCF-7 breast cancer cells (E-Screen assay) was applied for quantitative determination of total estrogenic activity in 24-h composite effluent samples from 16 municipal and two industrial sewage treatment plants (STPs) in the state of Baden-Wurttemberg, southwestern Germany. The estrogenic efficacy relative to the positive control, 17beta-estradiol, was between 26 and 74% (median, 48%) for the 16 municipal STPs. Estradiol equivalent concentrations (EEQs) were between 0.2 and 7.8 ng/L (median, 1.6 ng/L) and, thereby, were lower than those found in a pilot study, which revealed EEQs of greater than 10 ng/L in the effluents of two other STPs. The EEQs in 14 of the 16 effluent samples were very similar (0.9-3.3 ng/L), indicating a rather constant input of estrogenic substances via STPs into rivers. Additional activated charcoal filtration turned out to be very efficient in further eliminating estrogenic activity from effluents. The EEQs of the E-Screen assay and those calculated from the results of extensive chemical analysis using the estradiol equivalency factors determined for 13 natural and synthetic estrogenic substances were comparable for most of the effluent samples. 17beta-Estradiol, 17alpha-ethinylestradiol, and, to a lesser extent, estrone contributed to 90% or more of the EEQ value.
TL;DR: In this paper, a system of terms applicable to ordered microporous and mesoporous materials is proposed, and rules for writing a standardized crystal chemical formula for such materials are presented.
Abstract: A system of terms applicable to ordered microporous and mesoporous materials is proposed, and rules for writing a standardized crystal chemical formula for such materials are presented. The recommendations are based both on common usage and on a systematic classification scheme. The nomenclature has been developed to encompass all inorganic materials with ordered, accessible pores with free diameters of less than 50 nm. The crystal chemical formula describes the chemical composition of both the guest species and the host, the structure of the host, the structure of the pore system, and the symmetry of the material. This formula can be simplified or expanded to suit the user's requirements.
01 Dec 2001
TL;DR: A view-based approach to recognize free-form objects in range images using a set of local features that are easy to calculate and robust to partial occlusions and a multidimensional histogram to obtain highly discriminant classifiers without the need for segmentation is explored.
Abstract: The paper explores a view-based approach to recognize free-form objects in range images We are using a set of local features that are easy to calculate and robust to partial occlusions By combining those features in a multidimensional histogram, we can obtain highly discriminant classifiers without the need for segmentation Recognition is performed using either histogram matching or a probabilistic recognition algorithm We compare the performance of both methods in the presence of occlusions and test the system on a database of almost 2000 full-sphere views of 30 free-form objects The system achieves a recognition accuracy above 93% on ideal images, and of 89% with 20% occlusion
TL;DR: An overview and classification of optical burst switching schemes and present burst reservation concepts is given and a new analysis is introduced that allows to calculate the loss probabilities of a two-class system based on the reservation mechanism just-enough-time for arbitrary offsets.
Abstract: Summary In this paper, we give an overview and classification of optical burst switching schemes and present burst reservation concepts. The performance of various basic reservation mechanisms proposed in literature is compared. Furthermore, a new analysis is introduced that allows to calculate the loss probabilities of a two-class system based on the reservation mechanism just-enough-time (JET) for arbitrary offsets. Finally, a variety of new results is presented including the dependence of burst loss probabilities on offset, burst length distribution, and interarrival distribution.
TL;DR: It is postulated that a large fraction of sponge-associated bacteria resides permanently in the Aplysina aerophoba mesohyl pointing to a highly integrated interaction between the host sponge and associated microorganisms.
TL;DR: In this article, two different techniques for the electronic surface passivation of silicon solar cells, the plasmaenhanced chemical vapour deposition of silicon nitride (SiN) and the fabrication of thin thermal silicon oxide/plasma SiN stack structures, are investigated.
Abstract: Two different techniques for the electronic surface passivation of silicon solar cells, the plasma-enhanced chemical vapour deposition of silicon nitride (SiN) and the fabrication of thin thermal silicon oxide/plasma SiN stack structures, are investigated. It is demonstrated that, despite their low thermal budget, both techniques are capable of giving an outstanding surface passivation quality on the low-resistivity (∼1 � cm) p-Si base as well as on n + -diffused solar cell emitters with the oxide/nitride stacks showing a much better thermal stability. Both techniques are then applied to fabricate frontand rear-passivated silicon solar cells. Open-circuit voltages in the vicinity of 670 mV are obtained with both passivation techniques on float-zone single-crystalline silicon wafers, demonstrating the outstanding surface passivation quality of the applied passivation schemes on real devices. All-SiN passivated multicrystalline silicon solar cells achieve an open-circuit voltage of 655 mV, which is amongst the highest open-circuit voltages attained on this kind of substrate material. The high open-circuit voltage of the multicrystalline silicon solar cells results not only from the excellent degree of surface passivation but also from the ability of the cell fabrication to maintain a relatively high bulk lifetime (>20 µs) due to the low thermal budget of the surface passivation process.
TL;DR: Host factors alone or in combination with the viral AC1 protein are necessary and sufficient for the production of RDR intermediates, and the consequences of an inherent geminiviral recombination activity for the use of pathogen‐derived resistance traits are discussed.
Abstract: Geminiviruses have spread worldwide and have become increasingly important in crop plants during recent decades. Recombination among geminiviruses was one major source of new variants. Geminiviruses replicate via rolling circles, confirmed here by electron microscopic visualization and two-dimensional gel analysis of Abutilon mosaic virus (AbMV) DNA. However, only a minority of DNA intermediates are consistent with this model. The majority are compatible with recombination-dependent replication (RDR). During development of naturally infected leaves, viral intermediates compatible with both models appeared simultaneously, whereas agro-infection of leaf discs with AbMV led to an early appearance of RDR forms but no RCR intermediates. Inactivation of viral genes ac2 and ac3 delayed replication, but produced the same DNA types as after wild-type infection, indicating that these genes were not essential for RDR in leaf discs. In conclusion, host factors alone or in combination with the viral AC1 protein are necessary and sufficient for the production of RDR intermediates. The consequences of an inherent geminiviral recombination activity for the use of pathogen-derived resistance traits are discussed.
TL;DR: A survey on these new solid bases, their applications in heterogeneous catalysis and new spectroscopic techniques allowing a more detailed investigation of base sites and adsorbates on working catalysts is given in this paper.
TL;DR: In this article, the dominant recombination mechanism in ZnO/CdS/Cu(In,Ga)Se 2 heterojunction devices is reviewed and the role of Cd and Cu diffusion during junction formation and air-annealing of the completed device.
TL;DR: In this paper, the microplane material model for concrete based on the relaxed kinematic constraint is presented, aimed to be used for three-dimensional damage and fracture analysis of concrete and reinforced concrete structures in the framework of smeared crack approach.
TL;DR: A new finite element method which uses weighted extended B-splines on a regular grid as basis functions for solving Dirichlet problems on bounded domains in arbitrary dimensions yields smooth, high order accurate approximations with relatively low dimensional subspaces.
Abstract: We describe a new finite element method which uses weighted extended B-splines on a regular grid as basis functions for solving Dirichlet problems on bounded domains in arbitrary dimensions. This web-method does not require any grid generation and can be implemented very efficiently. It yields smooth, high order accurate approximations with relatively low dimensional subspaces.
01 May 2001
TL;DR: In this article, the authors consider the challenges facing manufacturers today: Efforts to increase efficiency throughout the product life cycle do not only mean extended responsibili, but also mean extended responsibility.
Abstract: Thinking in terms of product life cycles is one of the challenges facing manufacturers today: Efforts to increase efficiency throughout the life cycle do not only mean extended responsibili...
TL;DR: In this article, a theory is suggested which assumes a frozen dipole moment connected with the grain boundaries which induces the polar phase in the grain bulk in correlation with the bulk soft-mode frequency.
Abstract: Thorough Raman and infrared (IR) reflectivity investigations of nominally pure ${\mathrm{SrTiO}}_{3}$ ceramics in the 10--300 K range have revealed a clear presence of the polar phase whose manifestation steeply increases on cooling. The Raman strengths of the Raman-forbidden IR modes are proportional to ${\ensuremath{\omega}}_{\mathrm{TO}1}^{\ensuremath{-}\ensuremath{\alpha}}(\ensuremath{\alpha}\ensuremath{\approx}1.6)$ where ${\ensuremath{\omega}}_{\mathrm{TO}1}$ is the polar soft mode frequency. No pronounced permittivity dispersion is observed below the soft mode frequency so that, as in single crystals, the static permittivity is essentially determined by the soft mode contribution. A theory is suggested which assumes a frozen dipole moment connected with the grain boundaries which induces the polar phase in the grain bulk in correlation with the bulk soft-mode frequency. This stiffens slightly the effective soft mode response and reduces the low-temperature permittivity compared to that of single crystals. Moreover, the polar soft mode strongly couples to the ${E}_{g}$ component of the structural soft doublet showing that the polar axis is perpendicular to the tetragonal axis below the structural transition which is shifted to 132 K in our ceramics. Whereas the ${\mathrm{TiO}}_{6}$ octahedra tilt (primary order parameter) below the structural transition corresponds to that in single crystals, much smaller ${A}_{1g}\ensuremath{-}{E}_{g}$ splitting of the structural soft doublet shows that the tetragonal deformation (secondary order parameter) is nearly 10 times smaller, apparently due to the grain volume clamping in ceramics.
TL;DR: It is found that spatial ordering of the particles is a key factor in the force response of granular packings, and ordered packings have a propagative component that does not occur in disordered packings.
Abstract: We experimentally determine ensemble-averaged responses of granular packings to point forces, and we compare these results to recent models for force propagation in a granular material. We use 2D granular arrays consisting of photoelastic particles: either disks or pentagons, thus spanning the range from ordered to disordered packings. A key finding is that spatial ordering of the particles is a key factor in the force response. Ordered packings have a propagative component that does not occur in disordered packings.
TL;DR: In this paper, the authors proposed a non-intentional, process related approach to improve the performance of a CuInSe2 solar cell by controlling intentional band gap grading via Ga/In and S/Se grading during the deposition.
TL;DR: A gas-kinetic (Boltzmann-like) traffic equation that is not only suited for low vehicle densities, but also for the high-density regime, as it takes into account the forwardly directed interactions, effects of vehicular space requirements like increased interaction rates, and effects of velocity correlations that reflect the bunching of cars, at least partially are presented.
Abstract: We present a gas-kinetic (Boltzmann-like) traffic equation that is not only suited for low vehicle densities, but also for the high-density regime, as it takes into account the forwardly directed interactions, effects of vehicular space requirements like increased interaction rates, and effects of velocity correlations that reflect the bunching of cars, at least partially. From this gas-kinetic equation, we systematically derive the related macroscopic traffic equations. The corresponding partial differential equations for the vehicle density and average velocity are directly related to the quantities characterizing individual driver–vehicle behavior, and, as we show by calibration of the model, their optimal values have the expected order of magnitude. Therefore, the model allows to investigate the influences of varying street and weather conditions or freeway control measures. We point out that, because of the forwardly directed interactions, the macroscopic equations contain non-local instead of diffusion or viscosity terms. This resolves some of the inconsistencies found in previous models and allows for a fast and robust numerical integration, so that several thousand freeway kilometers can be simulated in real-time. It turns out that the model is in good agreement with the experimentally observed properties of freeway traffic flow. In particular, it reproduces the characteristic outflow and dissolution velocity of traffic jams, as well as the phase transition to “synchronized” congested traffic. We also reproduce the five different kinds of congested states that have been found close to on-ramps (or bottlenecks) and present a “phase diagram” of the different traffic states in dependence of the main flow and the ramp flow, showing that congested states are often induced by perturbations in the traffic flow. Finally, we introduce generalized macroscopic equations for multi-lane and multi-userclass traffic. With these, we investigate the differences between multi-lane simulations and simulations of the effective one-lane model.
TL;DR: In this paper, microdiamonds associated with phlogopite, quartz, paragonite, phengite, apatite, and rutile are found as regular constituents of minute polyphase inclusions in garnet of ultrahigh-pressure (P ) metamorphic gneiss lenses within migmatites of the gnesiss-eclogite unit, Erzgebirge, Germany.
Abstract: Microdiamonds associated with phlogopite, quartz, paragonite, phengite, apatite, and rutile are found as regular constituents of minute polyphase inclusions in garnet of ultrahigh-pressure ( P ) metamorphic gneiss lenses within migmatites of the gneiss-eclogite unit, Erzgebirge, Germany. These aggregates are interpreted to represent original inclusions of a supercritical dense COH fluid rich in K, Na, and SiO 2 . From this fluid, diamond was precipitated as a daughter crystal due to cooling at ultrahigh- P conditions. Brittle failure of the garnet host due to overpressure during release of confining pressure is demonstrated by healed radial cracks. During further cooling, the silicate phase assemblage of the inclusions crystallized at reduced internal pressures outside the stability field of diamond, as indicated by the presence of quartz, paragonite, and plagioclase. It is proposed that the mica-dominated mineral assemblage of the inclusions formed by reaction between the fluid and the garnet host, the previously formed diamond daughter crystals being preserved metastably. These diamond-bearing inclusions provide an unequivocal record of dense supercritical COH fluids rich in alkalies and silica within subducted continental crust during ultrahigh- P metamorphism.