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This research investigates the gasification of hydrothermal-carbonized-biomass pellets, focusing on the synergistic impact of pellet size and moisture content on the production of hydrogen, methane, and carbon monoxide. The study employs a computational fluid dynamics (CFD) two-dimensional Eulerian approach to elucidate the intricate relationships between these critical parameters and their combined impact on gasification efficiency. The impact of moisture content and pellet size on reaction kinetics and heat transfer are explored to unravel the underlying mechanisms governing gasification of biomass for high yield combustible gases. In all four pellets size examined in the current study (5, 10, 15, and 20 mm), the lowest pellets size increased the cold gas, carbon conversion, and gasification efficiency by 10.78, 23.03, and 21.6%, respectively, as compared to the highest pellets size. The gasification efficiency sequentially declined from 61.6% to 35.2% when the moisture contents increased from 4.3% to 14.5%. The study established that pellet size and moisture content have a significant influence on hydrogen-carbon monoxide ratio. As a result, the outcomes of the current study can be relied on to increase or decrease the various components in syngas depending on the final purpose of the end product without the need to use gas composition control catalysts. This model can further be used to optimize more operating parameters like gasification temperature and equivalence ratio in relation to particle size and moisture content. • Gasification of hydrothermal carbonized biomass pellets in a downdraft gasifier using CFD modelling. • Smaller pellet sizes have a high tendency to stabilize gasification temperature. • Higher oxidation temperature improves endothermic reactions. • Pellet size and moisture content have a significant influence on carbon conversion, heating value, and cold gas efficiency. [ABSTRACT FROM AUTHOR]

The lack of a fully developed human cardiac model in vitro hampers the progress of many biomedical research fields including pharmacology, developmental biology, and disease modeling. Currently, available methods may only differentiate human induced pluripotent stem cells (iPSCs) into immature cardiomyocytes. To achieve cardiomyocyte maturation, appropriate modulation of cellular microenvironment is needed. This study aims to optimize a microfluidic system that enhances maturation of human iPSC-derived cardiomyocytes (iPSC-CMs) through cyclic pulsatile hemodynamic forces. Human iPSC-CMs cultured in the microfluidic system show increased alignment and contractility and appear more rod-like shaped with increased cell size and increased sarcomere length when compared to static cultures. Increased complexity and density of the mitochondrial network in iPSC-CMs cultured in the microfluidic system are in line with expression of mitochondrial marker genes MT-CO1 and OPA1. Moreover, the optimized microfluidic system is capable of stably maintaining controlled oxygen levels and inducing hypoxia, revealed by increased expression of HIF1α and EGLN2 as well as changes in contraction parameters in iPSC-CMs. In summary, this microfluidic system boosts the structural maturation of iPSC-CM culture and could serve as an advanced in vitro cardiac model for biomedical research in the future. The availability of in vitro human cardiomyocytes generated from induced pluripotent stem cells (iPSCs) opens the possibility to develop human in vitro heart models for disease modeling and drug testing. However, iPSC-derived cardiomyocytes remain structurally and functionally immature, which hinders their application. In this manuscript, we present an optimized and complete microfluidic system that enhances maturation of iPSC-derived cardiomyocytes through physiological cyclic pulsatile hemodynamic forces. Furthermore, we improved our microfluidic system by using a closed microfluidic recirculation and oxygen exchangers to achieve and maintain low oxygen in the culture chambers, which is suitable for mimicking the hypoxic condition and studying the pathophysiological mechanisms of human diseases in vitro. In the future, a variety of technologies including 3D tissue engineering could be integrated into our system, which may greatly extend the use of iPSC-derived cardiac models in drug development and disease modeling. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The interplay of turbulent flow and heterogeneous gasification reactions of char particles is studied using Reynolds-averaged and large-eddy simulations. Currently available submodels for char gasification are typically developed for laminar flow conditions. For that reason, the simulation results are used to assess the applicability of these models at higher particle Reynolds numbers. Two representative gasification conditions were chosen on the basis of simulation data obtained for two different entrained-flow gasifiers: a 2 mm particle at atmospheric pressure in an O 2 /CO 2 /H 2 O atmosphere at 2006 K and a 263 µm particle at 30 bar in another O 2 /CO 2 /H 2 O atmosphere at 1480 K. The Navier–Stokes equations for the flow field were solved and were coupled with energy and species conservation equations. Six gaseous chemical species, H 2 , O 2 , CO, CO 2 , H 2 O, N 2 , and solid carbon, were considered and a semi-global reaction mechanism was applied for the homogeneous gas-phase reactions. Three heterogeneous gas-solid reactions were modeled: the water gas reaction, the Boudouard reaction and the oxidation of carbon to create carbon monoxide. The modification of the reaction zone due to a changing wake structure is presented in this work and the effect of turbulent structures on the overall carbon conversion rate is outlined. The impact of flow oscillations on char consumption and the particle temperature distribution at particle Reynolds numbers of 500 and 1000 is shown to be moderate. [ABSTRACT FROM AUTHOR]

Soil organisms constitute multitrophic food webs, which are important determinants for nutrient and carbon flow through terrestrial systems. However, these complex interactions are not well understood, particular in the most cryptic compartment – the link between microorganisms and microfauna. The present study investigates binary trophic links between microbial prey and nematodes in a controlled semi-natural soil environment. A microcosm system with circulating airflow was filled with γ-irradiated arable soil (Luvisol), inoculated with 13C labelled microbial diet and nematode grazers, and incubated for 72 h. Signatures of 13C and CO 2 evolved from microcosms, soil phospholipid fatty acids and nematode densities were determined. Except for the model nematode Caenorhabditis elegans, all organisms joint in the 12 different investigated binary links represent dominant taxa at the arable field site. Studied were the fungal grazers Aphelenchoides saprophilus and Aphelenchus sp. in combination with the fungi Chaetomium globosum, Aspergillus terreus or Cryptococcus terreus as well as the bacterial grazers C. elegans and Acrobeloides buetschlii in combination with the bacteria Pseudomonas putida , Kitasatospora sp. or Sphingomonas trueperi. The results assigned trophic and non-trophic interactions and considerable variation between binary links. The biomass decline of S. trueperi in presence of C. elegans as well as the increased release of 13C in links of C. globosum and A. terreus with Aphelenchus sp. and S. trueperi with A. buetschlii assign nematode grazing and thus a classical predator-prey system. Such direct trophic interactions can induce distinct C fluxes within a binary link as assigned by the increased density (i.e. biomass) of C. elegans when feeding on S. trueperi. In contrast, the numbers of Aphelenchus sp. declined when feeding on A. terreus , and thus reduced C flow to the next trophic level. Grazing can also foster C allocation in microbial biomass via compensatory growth, as indicated e.g. for the link of Aphelenchus sp. with the fungi C. globosum and A. terreus. While these diverse responses to grazing were to be expected, the use of CO 2 and 13C measurements further revealed that non-trophic interactions shape C flux in a binary link, particularly in the bacterial channel. Besides the fungal link of C. terreus with Aphelenchus sp., non-trophic interactions were obvious for the bacterial links Kitasatospora sp. with C. elegans or A. buetschlii, and P. putida with A. buetschlii. The presence of nematodes caused a reduction in respiration (evolved CO 2), thus a decline in microbial activity. The formation of chemical and/or morphological defense is likely a reason for that reduced prey activity. For further studies the inclusion of such non-trophic interactions is necessary to achieve realistic models for C flow through soil food webs. • Microbial traits cause variation in palatability for nematode grazers. • Predator-prey interactions of nematodes within a functional guild differ. • Impact of non-trophic interactions on C flux depends on the specific binary link. [ABSTRACT FROM AUTHOR]

Highlights • An approach for providing real world data into driving simulator domain is presented. • The approach is explained with details about the data format and guideline examples. • The guidelines were validated by applying them on a complex urban reference track. • Developed guidelines and intermediate data format are provided for free. Abstract Development of driver assistance and automation systems relies on domain-specific formats for the geometrical and logical representation of road networks in simulation environments. The trend to simulate real world urban environments leads to increasing demands for such data which cannot be derived easily from cadastral or open source geodata. In contrast, specific surveying directly into these domain-specific formats quickly becomes time- and cost-consuming. The DLR in partnership with OEMs developed guidelines and a simplified data format to facilitate surveying into an intermediate, discrete geodata format which meets the requirements of both the governmental and the driving simulation domain. The intermediate format should serve as a data hub from which specific simulation formats can be derived automatically through the developed processing tool chain. In this article the need of such an approach is discussed, the data format and the guidelines explained as well as the feasibility and effort of this approach is examined in an urban use case in Germany covering the dedicated surveying of road sections followed by automatic processing into OpenDRIVE. [ABSTRACT FROM AUTHOR]

Microorganisms in forest soils provide essential ecosystem services, such as decomposition of organic matter and nutrient mineralization. However, microbial community structure and function can be affected by environmental conditions, such as regional climate and soil properties and, moreover, by human activity through forest management. We examined the biomass and composition of microbial assemblages in 150 forest stands in the organic layer (Oi, Oe, Oa) and upper mineral soil (0–10 cm) in three regions across Germany (Schwäbische Alb, Hainich-Dün, Schorfheide-Chorin) by phospholipid fatty acid (PLFA) analysis. Different explanatory environmental variables (total C, N, S, P, organic C, inorganic C, pH, water content) were identified. The intensity of land use was characterized with the Forest Management Intensity Index (ForMI). The total amount of PLFAs, as measure for microbial biomass, was different among the three regions both in the organic layer and mineral soil. In the organic layer, total PLFAs decreased from Schwäbische Alb over Hainich-Dün to Schorfheide-Chorin, with the latter comprising a fourfold and twofold lower amount in fungal and bacterial PLFAs, respectively. In contrast, in the mineral soil the forests in the Hainich-Dün showed the highest microbial biomass. Discriminant function analysis of PLFA pattern indicated that Gram-positive bacteria and fungi accounted mainly for the regional differences in the organic layer, whereas in the mineral soil additionally Gram-negative and actinobacteria were important. Redundancy analysis showed that PLFA profiles were predominantly affected by sampling site and environmental variables, with the water content in the organic layer and the soil texture in the mineral soil explaining most of the variability in microbial communities between the three regions. Additionally, forest stands were classified into four management groups (conifer; deciduous with low, medium, and high intensity) based on the ForMI. In the mineral soil, forest management accounted for a small proportion of the observed regional differences. Within regions, fungal biomass in the organic layer decreased with management intensity at the Schwäbische Alb and increased in the mineral soils of Hainich-Dün region. Microbial community structure discriminated coniferous and deciduous forests in all three regions, and moreover showed a separation based on forest management intensity in the Schorfheide-Chorin. In conclusion, microbial biomass and community composition in forest organic layer and mineral soil were more influenced by regional conditions, including environmental properties such as moisture, soil texture, C/N ratio and pH, than by forest management intensity. However, within given environments, microbial assemblages can be influenced by forest management, in particular through changes in the tree species composition. [ABSTRACT FROM AUTHOR]

CFD-based optimization provides an efficient tool to improve systems in which conversion processes depend on a strong interaction between flow field and chemical reactions. The present work develops an improved multi-parameter and multi-objective optimization concept for reactive flow systems and demonstrates this concept for a new quench reactor. Response surface methods (metamodels) are used within the metamodel-based optimization process to accelerate the optimization rapidly. Different metamodels such as polynomials, K-nearest, radial basis functions, anisotropic Kriging, smoothing spline analysis of variance, and artificial neural networks are applied and carefully analyzed. It can be shown that radial basis function metamodels in combination with a certain number of CFD calculations provide a robust and efficient optimization scheme. The computational effort can be reduced by a factor of 17, which provides a reliable basis to optimize more complex reactive flow systems, e.g. the high pressure partial oxidation of natural gas or crude oil. [ABSTRACT FROM AUTHOR]

In car-body production, the fixtures used for fixing the car-body panels during the joining processes predominantly consist of rigid constructions that are precise and specific for one car-model. In addition to the already presented automatic adaptation of such fixtures, and specific for the production of many different car-models using same fixture, different clamping robots have been developed. In order to meet the high quality requirements, the positional deviations of these clamping robots are adjusted due to different external loads. This control loop is carried out using a combination of finite element method, mathematical algorithms and modern methods of artificial intelligence. [ABSTRACT FROM AUTHOR]

The occurrence of sugar alcohols is ubiquitous among plants. Physiochemical properties of sugar alcohols suggest numerous primary and secondary functions in plant tissues and are often well documented. In addition to functions arising from physiochemical properties, the synthesis of sugar alcohols may have significant influence over photosynthetic, respiratory, and developmental processes owing to their function as a large sink for photosynthates. Sink strength is demonstrated by the high concentrations of sugar alcohols found in plant tissues and their ability to be readily transported. The plant scale distribution and physiochemical function of these compounds renders them strong candidates for functioning as stress metabolites. Despite this, several aspects of sugar alcohol biosynthesis and function are poorly characterised namely: 1) the quantitative characterisation of carbon flux into the sugar alcohol pool; 2) the molecular control governing sugar alcohol biosynthesis on a quantitative basis; 3) the role of sugar alcohols in plant growth and ecology; and 4) consequences of sugar alcohol synthesis for yield production and yield quality. We highlight the need to adopt new approaches to investigating sugar alcohol biosynthesis using modern technologies in gene expression, metabolic flux analysis and agronomy. Combined, these approaches will elucidate the impact of sugar alcohol biosynthesis on growth, stress tolerance, yield and yield quality. [ABSTRACT FROM AUTHOR]

• Nematode communities were shaped by environmental filtering. • Tree type, ground cover and resources were drivers in the organic layer. • Abiotic conditions (water content, soil type) impacted the mineral soil most. • Specific nematode families correlated with forest stand age and density. • Management practice increasing deadwood had no effects. A key to forest productivity is structure and function of the biotic microbiome in the soil, which determines nutrient mineralisation and consequently tree growth and fitness. Soil nematodes are a dominant part of these assemblages, with an important role in the associated micro-food web. However, nothing is known about how forest management and soil properties affect soil nematodes. This study investigated the nematode communities in the organic layer and mineral soil of 150 forests located in three different German regions. Fifty forest stands each were studied in Schwäbische Alb (ALB), Hainch-Dün (HAI) and Schorfheide-Chorin (SCH). The effect of forest management (forest management index – ForMI, silvicultural management intensity indicator – SMI), soil properties (total C, N, S, P, organic C, inorganic C, pH, water content) and microbial food source (phospholipid fatty acids - PLFA) on nematode density, community and ecological indices were assessed. The nematode density in the organic layer of the forests was with a mean of 290 individuals g−1 DW comparable across all three regions, while in the mineral soil nematode density was significant lower in SCH. Here, dry sandy soils are frequently stocked with intensively managed pine forests, and the associated fungal-based decomposition is reflected in a greater proportion of fungal-feeding nematodes and a higher Channel Index. Effects of region and soil layer were mirrored by the structure of the nematode community. Organic layer and mineral soil differed distinctly, while in the latter SCH separated from ALB and HAI. The nematode community was predominantly affected by region, soil properties and resources, with microbial diet as driving factor in the organic layer, whereas soil parameters were more important in mineral soil. In comparison, the influence of forest management was low, with ForMI and SIM together explaining 8% (organic layer) and 4% (mineral soil) of the overall variation. Most remarkable, the nematode community in HAI, a region dominated by broad-leaf forests, was resilient to management intensity in the organic layer. On the other hand, management practice had family-specific impact: In the organic layer of ALB, the density of the bacterial-feeding Teratocephalidae and the fungal-feeding Aphelenchoididae increased with higher Inonat (indicates non-natural tree species) and higher SMIr (addresses stand age and species selection related to the risk of stand loss). In sum, the structure and function of nematode communities were driven by both, biotic factors such food source (i.e. the soil layer inhabited) and abiotic factors such as soil type and climate (i.e. region). Furthermore, forest management can affect nematode communities, mainly by the selected tree species, but also by stand age and density. [ABSTRACT FROM AUTHOR]

Summary Lymphocytes represent basic components of vertebrate adaptive immune systems, suggesting the utility of non-mammalian models to define the molecular basis of their development and differentiation. Our forward genetic screens in zebrafish for recessive mutations affecting early T cell development revealed several major genetic pathways. The identification of lineage-specific transcription factors and specific components of cytokine signaling and DNA replication and/or repair pathways known from studies of immunocompromised mammals provided an evolutionary cross-validation of the screen design. Unexpectedly, however, genes encoding proteins required for pre-mRNA processing were enriched in the collection of mutants identified here. In both zebrafish and mice, deficiency of the splice regulator TNPO3 impairs intrathymic T cell differentiation, illustrating the evolutionarily conserved and cell-type-specific functions of certain pre-mRNA-processing factors for T cell development. [ABSTRACT FROM AUTHOR]

For the development of reliable numerical models of entrained flow gasifiers it is crucial to understand and to model correctly the interactions between the hot gas-flow and the coal particles undergoing pyrolysis and char conversion. In this work a laboratory-scale entrained flow coal gasifier was investigated numerically. Based on the detailed analysis of the particle trajectories, the interaction between the flow field and coal particles of different sizes was carefully discussed and analyzed. For small, medium, and large particles, the primary regions for devolatilization, oxidation, and gasification were detected, and the conversion behavior for these particle fractions was quantified in terms of pyrolysis time, residence time, and overall conversion rate. Additional particle-resolved CFD calculations were carried out for representative particles of different sizes in order to study the heat and mass transfer of the isolated particles in detail. Pyrolyzing coal particles and combusting or gasifying char particles were considered at several positions in the reactor, where each location is characterized by different gas compositions and temperatures. For these particles, the flow field, and the species and temperature distributions in the boundary layer are discussed. The particle-resolved calculations demonstrate the impact of the particle Reynolds number and the influence of the mass flow from the particle to the surrounding gas on the overall heat and mass transfer. [ABSTRACT FROM AUTHOR]

Tetrapyrroles are macrocyclic molecules with various structural variants and multiple functions in Prokaryotes and Eukaryotes. Present knowledge about the metabolism of tetrapyrroles reflects the complex evolution of the pathway in different kingdoms of organisms, the complexity of structural and enzymatic variations of enzymatic steps, as well as a wide range of regulatory mechanisms, which ensure adequate synthesis of tetrapyrrole end-products at any time of development and environmental condition. This review intends to highlight new findings of research on tetrapyrrole biosynthesis in plants and algae. In the course of the heme and chlorophyll synthesis in these photosynthetic organisms, glutamate, one of the central and abundant metabolites, is converted into highly photoreactive tetrapyrrole intermediates. Thereby, several mechanisms of posttranslational control are thought to be essential for a tight regulation of each enzymatic step. Finally, we wish to discuss the potential role of tetrapyrroles in retrograde signaling and point out perspectives of the formation of macromolecular protein complexes in tetrapyrrole biosynthesis as an efficient mechanism to ensure a fine-tuned metabolic flow in the pathway. This article is part of a Special Issue entitled: Chloroplast Biogenesis. [ABSTRACT FROM AUTHOR]

The non-catalytic reforming of natural gas to syngas was studied with test runs at the semi-industrial scale test plant HP POX. The product gas composition, and gas and wall temperatures across the reactor were considered at 50, 60 and 70 bar(g), while the reactor temperature was varied between 1200 and 1400 °C. In addition, the flame structure was studied using optical measurements. The experiment was designed to provide a challenging benchmark for numerical modeling. For that reason, the reactor geometry, boundary conditions, and the experimental data are provided in such a way that the results can easily be reproduced using CFD. [ABSTRACT FROM AUTHOR]

This work is devoted to the three-dimensional numerical investigation of a chemical reacting porous carbon particle moving in a hot O 2 /CO 2 gas. The porous particle was represented by an agglomerate of small monodisperse spherical particles distributed inside a sphere. The ambient temperature was systematically varied in a range between 1200 and 2500 K. To solve the Navier–Stokes equations for the flow field coupled with the energy and species conservation equations, a finite volume solver was applied. In addition to the solid carbon the model incorporates six gaseous chemical species (O 2 , CO, CO 2 , H 2 , H 2 O, and N 2 ). The reaction mechanism includes semi-global carbon monoxide oxidation, the forward and backward water–gas-shift reaction, and four heterogeneous reactions. The ambient medium was assumed to be nearly dry. The main objective of this work was to understand the char conversion processes inside a porous carbon particle. In particular, the change of regimes depending on the ambient gas temperature and the influence of the flow velocity on the processes inside the porous particle were studied in detail. As a reference case the oxidation of a solid non-permeable sphere moving in a hot O 2 /CO 2 gas was considered, and the results for the porous particle are discussed and compared against the reference case. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reduced order modeling of non-catalytic partial oxidation of natural gas. • Low computational effort through a physics-based and compact model. • Validation against semi-industrial test plant experiments and CFD. • Demonstrated exibility and reliability of the model for a broad spectrum of operating parameters. • Analysis of conversion processes in different reactor zones. A reduced order model (ROM) for the non-catalytic partial oxidation (POX) of natural gas was developed and validated against large-scale numerical and experimental results. The ROM utilizes a network of perfectly stirred reactors, each describing a distinctive reactor zone and corresponding conversion processes. The zone definition is based on the CFD calculation of reactive flow, resulting in a compact, physics-based model that is valid for a broad range of POX reactors. The ROM is capable of predicting global reactor characteristics and flow field pattern within a short period of time, enabling the optimization of reactor geometry and the boundary and operating conditions. Additionally, the ROM can be used to evaluate detailed chemical reactions mechanisms. The ROM is validated against semi-industrial process data, and used to analyze the influence of each reactor zone on the overall species conversion. A new correlation between the fuel slip from the burner to the downstream reactor zones, the steam injection, and the λ value is built. [ABSTRACT FROM AUTHOR]

The environmental conditions under which the availability of inorganic nutrients such as nitrogen (N) and phosphorus (P) influence soil microbial growth are poorly understood, especially with regards to how fertilization changes specific aspects of microbial growth such as carbon-use efficiency (CUE). Microbial CUE is the fraction of C converted into biomass out of all C taken in and plays a critical role in global C budgets. Using the 18O labeled water method we tested short vs. long-term effects of N and/or P fertilization on microbial growth, CUE, and C, N, and P-acquiring enzyme activities in two soils from an oak-savanna, which differ in their soil organic matter (SOM) content. We hypothesized that soils with more SOM (from under tree canopies) would have higher microbial growth rates than soils with less SOM (from open grassland), and that microbial growth and CUE would increase with fertilization. We further hypothesized that these increases would be associated with a decrease in enzyme activity and a shift towards older SOM substrates in the short-term, in contrast to substrates from recently fixed C resulting from increased plant productivity in the long-term. We found that nutrient additions did not affect microbial growth or CUE in the relatively high SOM habitat on either time scale. In contrast, the low SOM habitat had lower growth and CUE when single nutrients were added, with significantly reduced growth when P alone was added, but was unchanged when N and P were added together. Our results show that short-term, stoichiometric imbalances can reduce microbial growth and that microbial growth at this site is limited not by nutrients but by the amount of C available to soil microbes. • Microbial growth, carbon-use efficiency, and enzyme activity were unchanged by short or long-term addition of N and P. • Soil organic matter content was a primary control on microbial growth and the short-term effect of adding N or P alone. • Addition of N and P together led to changes in microbially respired Δ14C signatures. [ABSTRACT FROM AUTHOR]

Abstract: This work considers heat and fluid flow past ellipsoidal and cubic particles at different angles of attack. Although numerous works have investigated drag forces for spherical and non-spherical particles, there are very few works about Nusselt number relations for such particles, especially in cases where the particles are not oriented in a streamwise direction. Motivated by this fact, three-dimensional numerical simulations of heat and fluid flow past non-spherical particles at different angles of attack were performed. In particular, a laminar-steady flow past ellipsoidal and cubic particles was considered and the results compared against those for a spherical particle. In order to take into account the angle of attack in semi-empirical models, new correlations for the drag, lift and torque coefficients and for the Nusselt number were developed and the accuracy of the closures is discussed in comparison with published models. [Copyright &y& Elsevier]

Abstract: Based on pressure tide gauge observations at three sites off the Atlantic coast of Tierra del Fuego main island, time series spanning one to seven months of bottom pressure and sea-level variations are derived and analysed to reveal the major driving mechanisms. Ocean tides account for 99.5% of the total energy of the sea-level variations. The amplitudes and phases of a comprehensive set of tidal constituents resulting from a harmonic tidal analysis are presented. Exceptionally large shallow-water tides are identified. The second largest contribution is due to the local inverse barometer model accounting for up to 65% of the variance of the tide residual sea-level variations. Close to the shore a significant topographic modulation of the sea-level variations is revealed. The in situ observations are compared with six recent global ocean tide models, official tide tables, and sea-surface heights derived from satellite altimetry data. The amplitudes and phases predicted by the ocean tide models for the semidiurnal and diurnal constituents agree with those derived from our tide gauge records on average within 2cm and 5°, respectively. In the time domain the tidal signal represented by the models deviates typically by a few decimetres from that extracted from our records. Absolute altimeter biases were determined for the Jason-2, Jason-1 extended mission, and Envisat satellite altimeters. Relative sea-level variations are represented by the altimetry data with an accuracy of the order of 5cm. [Copyright &y& Elsevier]

Abstract: This work is devoted to the numerical calculation of heat and fluid flow past spherical particles and non-spherical particles of various shapes. Although numerous works have investigated drag forces (cd ) for spherical and non-spherical particles, works about the Nusselt number (Nu) relations for non-spherical particles are rare. Motivated by this fact, as a first step we consider cuboid, spherical and ellipsoidal particles in steady-state regimes corresponding to Reynolds numbers (Re) from 10 up to 250. Due to the asymmetric flow existing when Re approaches the value of 250, all simulations are made using a three-dimensional domain. Good agreement was observed when our numerical results gained for the sphere were compared with published values for drag coefficients and Nusselt numbers. Based on the analysis of numerical results obtained for non-spherical particles we found out that in addition to the Reynolds number three geometry parameters influence particle-fluid interaction: the drag coefficient depends primarily on the normalized longitudinal length, while both the sphericity and the crosswise sphericity influence the Nusselt number. For that reason new correlations are developed for both the drag coefficient and the Nusselt number. The accuracy of the closures developed for cd and Nu is discussed in a comparison with published models. [Copyright &y& Elsevier]

Abstract: We have conducted a feasibility study for the geostationary monitoring of the diurnal variation of tropospheric NO2 over Tokyo. Using NO2 fields from a chemical transport model, synthetic spectra were created by a radiative transfer model, SCIATRAN, for summer and winter cases. We then performed a Differential Optical Absorption Spectroscopy (DOAS) analysis to retrieve NO2 slant column densities (SCDs), and after converting SCDs into vertical column densities (VCDs), we estimated the precision of the retrieved VCDs. The simulation showed that signal-to-noise ratio (SNR)⩾500 is needed to detect the diurnal variation and that SNR⩾1000 is needed to observe the local minimum occurring in the early afternoon (LT13–14) in summer. In winter, the detection of the diurnal variation during LT08–15 needs SNR⩾500, and SNR⩾1000 is needed if early morning (LT07) and early evening (LT16) are included. The currently discussed sensor specification for the Japanese geostationary satellite project, GMAP-Asia, which has a horizontal resolution of 10km and a temporal resolution of 1hr, has demonstrated the performance of a precision of several percent, which is approximately corresponding to SNR=1000–2000 during daytime and SNR⩾500 in the morning and evening. We also discuss possible biases caused by the temperature dependence of the absorption cross section utilized in the DOAS retrieval, and the effect of uncertainties of surface albedo and clouds on the estimation of precisions. [Copyright &y& Elsevier]

The East Asian countries have been affected by atmospheric gaseous pollutants (in particular SO2) transported from the Asian continent as well as Asian dust storms. For investigation of the impact of these anthropogenic trace gases on local air quality in Korea, ground-based measurements using a Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) system and in situ gas analyzers as well as synoptic meteorological data and scattered sunlight spectra obtained by the satellite-borne instrument, Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) launched on board of Environmental Satellite (ENVISAT) in March 2002, were utilized to retrieve SO2 and trace its transport from the Asian continent to Korea in May 2005. The ground-based measurements were carried out in the region of interest, at Korea Global Watch Observatory (KGAWO) in Korea. Plumes of high SO2 over Chinese industrial areas and their transport to the Korean peninsula were observed in SCIAMACHY data in the period of 21–26 May 2005. Highly increased SO2 was measured by the MAX-DOAS system and in situ gas analyzer in the period of 27–29 May 2005 at KGAWO. These observations are supported by the meteorological results that the air-masses picking up these high SO2 plumes while passing over the Chinese industrial and metropolitan areas were transported to the Korean peninsula. The tropospheric SO2 VCDs over these Chinese industrial and metropolitan areas ranged up to 1.4×1017 molcm−2 in SCIAMACHY data. These SO2 plumes resulted in increased SO2 surface levels of up to 7.8ppbv (measured by an in situ gas analyzer) at KGAWO. [Copyright &y& Elsevier]

Abstract: Adaptation to aridity is considered a major factor in the evolution of the genus Eucalyptus. For the first time, targeted metabolite profiling has uncovered a quantitative yet discrete phytochemical link with eucalypt taxonomy. The distribution of cyclitols among Eucalyptus species, and a range of other Australian tree genera, support their proposed functions in plant tissues and provide putative links with the acclimation of trees to arid environments. [Copyright &y& Elsevier]