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Dielectric elastomers (DEs) are electroactive polymers commonly used in soft robotics. Bulky and stiff high‐voltage circuits are usually needed to control their operation. This article presents autonomous control in a multi‐functional device made entirely of DEs. A gripper made of DE actuators is controlled by dielectric elastomer sensors through an electrical circuit. The circuit itself is composed of a network of actuators and sensors. The final structure requires only a constant power supply to work and produces its controlling signals. Every component can be manufactured simultaneously with the same materials and processes. At first, the logical control of the gripper is demonstrated by directly connecting a sensor to the gripper that opens when the sensor is stretched. Then, a DE level‐triggered flip‐flop (also called latch) is introduced to have bi‐stability between open and closed states. Finally, the latch is integrated inside the gripper, allowing it to sense objects. The device autonomously grips an object that is placed in it, resembling the closing mechanism of the plant Dionaea muscipula, also known as the Venus flytrap. [ABSTRACT FROM AUTHOR]

Airborne imaging differential optical absorption spectroscopy (DOAS), ground-based stationary DOAS, and car DOAS measurements were conducted during the S5P-VAL-DE-Ruhr campaign in September 2020. The campaign area is located in the Rhine-Ruhr region of North Rhine-Westphalia, western Germany, which is a pollution hotspot in Europe comprising urban and large industrial sources. The DOAS measurements are used to validate spaceborne NO 2 tropospheric vertical column density (VCD) data products from the Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI). Seven flights were performed with the airborne imaging DOAS instrument for measurements of atmospheric pollution (AirMAP), providing measurements that were used to create continuous maps of NO 2 in the layer below the aircraft. These flights cover many S5P ground pixels within an area of 30 km × 35 km and were accompanied by ground-based stationary measurements and three mobile car DOAS instruments. Stationary measurements were conducted by two Pandora, two Zenith-DOAS, and two MAX-DOAS instruments. Ground-based stationary and car DOAS measurements are used to evaluate the AirMAP tropospheric NO 2 VCDs and show high Pearson correlation coefficients of 0.88 and 0.89 and slopes of 0.90 ± 0.09 and 0.89 ± 0.02 for the stationary and car DOAS, respectively. Having a spatial resolution of about 100 m × 30 m, the AirMAP tropospheric NO 2 VCD data create a link between the ground-based and the TROPOMI measurements with a nadir resolution of 3.5 km × 5.5 km and are therefore well suited to validate the TROPOMI tropospheric NO 2 VCD. The observations on the 7 flight days show strong NO 2 variability, which is dependent on the three target areas, the day of the week, and the meteorological conditions. The AirMAP campaign data set is compared to the TROPOMI NO 2 operational offline (OFFL) V01.03.02 data product, the reprocessed NO 2 data using the V02.03.01 of the official level-2 processor provided by the Product Algorithm Laboratory (PAL), and several scientific TROPOMI NO 2 data products. The AirMAP and TROPOMI OFFL V01.03.02 data are highly correlated (r=0.87) but show an underestimation of the TROPOMI data with a slope of 0.38 ± 0.02 and a median relative difference of - 9 %. With the modifications in the NO 2 retrieval implemented in the PAL V02.03.01 product, the slope and median relative difference increased to 0.83 ± 0.06 and + 20 %. However, the modifications resulted in larger scatter and the correlation decreased significantly to r=0.72. The results can be improved by not applying a cloud correction for the TROPOMI data in conditions with high aerosol load and when cloud pressures are retrieved close to the surface. The influence of spatially more highly resolved a priori NO 2 vertical profiles and surface reflectivity are investigated using scientific TROPOMI tropospheric NO 2 VCD data products. The comparison of the AirMAP campaign data set to the scientific data products shows that the choice of surface reflectivity database has a minor impact on the tropospheric NO 2 VCD retrieval in the campaign region and season. In comparison, the replacement of the a priori NO 2 profile in combination with the improvements in the retrieval of the PAL V02.03.01 product regarding cloud heights can further increase the tropospheric NO 2 VCDs. This study demonstrates that the underestimation of the TROPOMI tropospheric NO 2 VCD product with respect to the validation data set has been and can be further significantly improved. [ABSTRACT FROM AUTHOR]

Clouds have a strong impact on satellite measurements of tropospheric trace gases in the ultraviolet, visible, and near-infrared spectral ranges from space. Therefore, trace gas retrievals rely on information on cloud fraction, cloud albedo, and cloud height from cloud products. In this study, the cloud parameters from different cloud retrieval algorithms for the Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI) are compared: the Optical Cloud Recognition Algorithm (OCRA) a priori cloud fraction, the Retrieval Of Cloud Information using Neural Networks (ROCINN) CAL (Clouds-As-Layers) cloud fraction and cloud top and base height, the ROCINN CRB (Clouds-as-Reflecting-Boundaries) cloud fraction and cloud height, the Fast Retrieval Scheme for Clouds from the Oxygen A-band (FRESCO) cloud fraction, the interpolated FRESCO cloud height from the TROPOMI NO 2 product, the cloud fraction from the NO 2 fitting window, the O 2 –O 2 cloud fraction and cloud height, the Mainz Iterative Cloud Retrieval Utilities (MICRU) cloud fraction, and the Visible Infrared Imaging Radiometer Suite (VIIRS) cloud fraction. Two different versions of the TROPOMI cloud products OCRA/ROCINN, FRESCO, and the TROPOMI NO 2 product are included in the comparisons (processor version 1.x and 2.x). Overall, the cloud parameters retrieved by the different algorithms show qualitative consistency in version 1.x and good agreement in version 2.x with the exception of the VIIRS cloud fraction, which cannot be directly compared to the other data. Differences between the cloud retrievals are found especially for small cloud heights with a cloud fraction threshold of 0.2, i.e. clouds that are particularly relevant for tropospheric trace gas retrievals. The cloud fractions of the different version 2 cloud products primarily differ over snow- and ice-covered pixels and scenes with sun glint, for which only MICRU includes an explicit treatment. All cloud parameters show some systematic problems related to the across-track dependence, where larger values are found at the edges of the satellite view. The consistency between the cloud parameters from different algorithms depends strongly on how the data are filtered for the comparison, for example, what quality value is used or whether snow- and ice-covered pixels are excluded from the analysis. In summary, clear differences were found between the results of various algorithms, but these differences are reduced in the most recent versions of the cloud data. [ABSTRACT FROM AUTHOR]

Summary: Due to their sessile nature, plants cannot escape adverse environmental conditions and evolved mechanisms to cope with sudden environmental changes. The reaction to variations in abiotic factors, also summarized as acclimation response, affects all layers of cellular functions and involves rapid modification of enzymatic activities, the metabolome, proteome and transcriptome on different timescales. One trait of plants acclimating to high light (HL) is the rapid transcriptional activation of the flavonoid biosynthesis (FB) pathway resulting in the accumulation of photoprotective and antioxidative flavonoids, such as flavonols and anthocyanins, in the leaf tissue. Although enormous progress has been made in identifying enzymes and transcriptional regulators of FB by forward and reverse genetic approaches in the past, the signals and signalling pathways permitting the conditional activation of FB in HL are still debated. With this Tansley Insight, we summarize the current knowledge on the proposed signals and downstream factors involved in regulating FB and will discuss their contribution to, particularly, HL‐induced accumulation of anthocyanins. [ABSTRACT FROM AUTHOR]

Airborne imaging differential optical absorption spectroscopy (DOAS), ground-based stationary and car DOAS measurements were conducted during the S5P-VAL-DE-Ruhr campaign in September 2020. The campaign area is located in the Rhine-Ruhr region of North Rhine-Westphalia,Western Germany, which is a pollution hotspot in Europe comprising urban and large industrial emitters. The measurements are used to validate space-borne NO2 tropospheric vertical column density data products from the Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI). Seven flights were performed with the airborne imaging DOAS instrument formeasurements of atmospheric pollution (AirMAP), providing measurements which were used to create continuous maps of NO2 in the layer below the aircraft. These flights cover many S5P ground pixels within an area of 30 kmx 35 km and were accompanied by ground-based stationary measurements and three mobile car DOAS instruments. Stationary measurements were conducted by two Pandora, two zenith-sky and two MAX-DOAS instruments distributed over three target areas. Ground-based stationary and car DOAS measurements are used to evaluate the AirMAP tropospheric NO2 vertical column densities and show high Pearson correlation coefficients of 0.87 and 0.89 and slopes of 0.93±0.09 and 0.98±0.02 for the stationary and car DOAS, respectively. Having a spatial resolution of about 100mx 30m, the AirMAP tropospheric NO2 vertical column density (VCD) data creates a link between the ground-based and the TROPOMI measurements with a resolution of 3.5 kmx 5.5 km and is therefore well suited to validate the TROPOMI tropospheric NO2 VCD. The measurements on the seven flight days show strong NO2 variability, which is dependent on the different target areas, the weekday, and the meteorological conditions. The AirMAP campaign dataset is compared to the TROPOMI NO2 operational off-line (OFFL) V01.03.02 data product, the reprocessed NO2 data, using the V02.03.01 of the official L2 processor, provided by the Product Algorithm Laboratory (PAL), and several scientific TROPOMI NO2 data products. The TROPOMI data products and the AirMAP data are highly correlated with correlation coefficients between 0.72 and 0.87, and slopes of 0.38±0.02 to 1.02±0.07. On average, TROPOMI tropospheric NO2 VCDs are lower than the AirMAP NO2 results. The slope increased from 0.38±0.02 for the operational OFFL V01.03.02 product to 0.83±0.06 after the improvements in the retrieval of the PAL V02.03.01 product were implemented. Different auxiliary data, such as spatially higher resolved a priori NO2 vertical profiles, surface reflectivity and the cloud treatment, are investigated using scientific TROPOMI tropospheric NO2 VCD data products to evaluate their impact on the operational TROPOMI NO2 VCD data product. The comparison of the AirMAP campaign dataset to the scientific data products shows that the choice of surface reflectivity data base has a minor impact on the tropospheric NO2 VCD retrieval in the campaign region and season. In comparison, the replacement of the a priori NO2 profile in combination with the improvements in the retrieval of the PAL V02.03.01 product regarding cloud heights has a major impact on the tropospheric NO2 VCD retrieval and increases the slope from 0.88±0.06 to 1.00±0.07. This study demonstrates that the underestimation of the TROPOMI tropospheric NO2 VCD product with respect to the validation dataset has been and can be further significantly improved. [ABSTRACT FROM AUTHOR]

Lake Vostok, East Antarctica, represents an extensive water surface at the base of the ice sheet. Snow, ice and atmospheric pressure loads applied anywhere within the lake area produce a hydrostatic response, involving deformations of the ice surface, ice–water interface and particle horizons. A modelling scheme is developed to derive height changes of these surfaces for a given load pattern. It is applied to a series of load scenarios, and predictions based on load fields derived from a regional climate model are compared to observational datasets. Our results show that surface height changes due to snow-buildup anomalies are damped over the lake area, reducing the spatial standard deviation by one-third. The response to air pressure variations, in turn, adds surface height variability. Atmospheric pressure loads may produce height changes of up to $\pm$ 4 cm at daily resolution, but decay rapidly with integration time. The hydrostatic load response has no significant impact neither on ICESat laser campaign biases determined over the lake area nor on vertical particle movements derived from GNSS observations. [ABSTRACT FROM AUTHOR]

Clouds have a strong impact on satellite measurements of tropospheric trace gases in the ultraviolet, visible, and near-infrared spectral ranges from space. Therefore, trace gas retrievals rely on information on cloud fraction, cloud albedo, and cloud height from cloud products. In this study, the cloud parameters from different cloud retrieval algorithms for Sentinel-5 Precursor (S5P) TROPOMI are compared: the OCRA a priori cloud fraction, the ROCINN CAL cloud fraction and cloud top and base height, the ROCINN CRB cloud fraction and cloud height, the FRESCO cloud fraction, the interpolated FRESCO cloud height from the TROPOMI NO2 product, the cloud fraction from the NO2 fitting window, the O2-O2 cloud fraction and cloud height, the MICRU cloud fraction, and the VIIRS cloud fraction. Two different versions of the TROPOMI cloud products OCRA/ROCINN, FRESCO, and the TROPOMI NO2 product are included in the comparisons (processor version 1.x and 2.x). Overall, the cloud parameters retrieved by the different algorithms show qualitative consistency in version 1.x and good agreement in version 2.x with the exception of the VIIRS cloud fraction, which cannot be directly compared to the other data. Differences between the cloud retrievals are found especially for small cloud heights with a cloud fraction threshold of 0.2, i.e., clouds that are particularly relevant for tropospheric trace gas retrievals. The cloud fractions of the different version 2 cloud products primarily differ over snow- and ice-covered pixels and scenes with sun glint, for which only MICRU includes an explicit treatment. All cloud parameters show some systematic problems related to the across-track dependence, where larger values are found at the edges of the satellite view. The consistency between the cloud parameters from different algorithms depends strongly on how the data is filtered for the comparison, e.g., what quality value is used or whether snow and ice-covered pixels are excluded from the analysis. In summary, clear differences were found between the results of various algorithms, but these differences are reduced in the most recent versions of the cloud data. [ABSTRACT FROM AUTHOR]

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 present study aims to analyze the interaction of chemical reactions, particle morphology change and hydrodynamics in fluidized-bed gasifiers. The char gasification in a batch fluidized-bed gasifier was modeled. The two-fluid model approach was coupled with an extended version of the uniform conversion model accounting for inert ash fraction. Model assumptions were confirmed via measurement of char density, porosity and particle size distribution at different stages of conversion in a lab-scale fluidized-bed gasifier. The CFD model correctly predicts the effects of particle structure change on chemical reactions, approved by a first of its kind comprehensive validation against unsteady experiments. Based on the validated CFD model, the interaction of hydrodynamics and local particle density variations due to chemical reactions is analyzed, and the effect of the initial bed height is studied. [Display omitted] • A batch fluidized-bed gasifier is modeled using the two-fluid model. • An extended uniform conversion model considering the ash fraction is applied. • The CFD model is successfully validated against unsteady gasification experiments. • The conversion model correctly predicts experimental char morphology change. • The particle density reduction during reaction improves the particle mixing. [ABSTRACT FROM AUTHOR]

Purpose: Three human papillomavirus (HPV) vaccines are available against up to nine HPV types. In Sweden, from 2012, Gardasil was offered to 10−12 year old girls through the school-based vaccination program, and as catchup vaccination for women up to 26 years. To obtain a baseline, and follow HPV vaccination effects, during 2008−2018, cervical and oral HPV prevalence were followed at a youth clinic in Stockholm, and in 2013 for comparison oral HPV prevalence was examined in high-school youth in a middle-sized county in Sweden. Methods: In this review, we discuss all our data with cervical and oral mouthwash samples that were collected and tested for 24−27 HPV types by a bead-based multiplex assay from 2008. Results: Compared with 2008−2011, with ~ 35% HPV16 and > 60% high risk (HR) HPV cervical prevalence at the youth clinic, a decrease of vaccine HPV types was observed between 2013 and 2018, with e.g., HPV16 falling to 5% in catchup vaccinated women and 15−18% in nonvaccinated women. Most common cervical HR-HPV types were HPV39, 51, 52, 56, and 59 together accounting for ~ 10% of cervical cancer, and where only HPV52 is included in Gardasil-9. At baseline 2009−2011, oral HPV prevalence was ~ 10% in unvaccinated youth at the youth clinic, but after 2013 it dropped to < 2% at the youth clinic and high schools. Conclusion: To conclude, Gardasil HPV types have decreased, but it is still important to follow remaining HR-HPV types and cancer development, since there is an ongoing increase in the incidence of HPV-associated tonsillar and base of tongue cancer, and cervical cancer in Sweden. [ABSTRACT FROM AUTHOR]

In recent years, it has become evident that plants perceive, integrate and communicate abiotic stress signals through chloroplasts. During the process of acclimation plastid-derived, retrograde signals control nuclear gene expression in response to developmental and environmental cues leading to complex genetic and metabolic reprogramming to preserve cellular homeostasis under challenging environmental conditions. Upon stress-induced dysfunction of chloroplasts, GENOMES UNCOUPLED (GUN) proteins participate in the repression of PHOTOSYNTHESIS-ASSOCIATED NUCLEAR GENES (PHANGs). Here, we show that the retrograde signal emitted by, or communicated through, GUN-proteins is also essential to induce the accumulation of photoprotective anthocyanin pigments when chloroplast development is attenuated. Comparative whole transcriptome sequencing and genetic analysis reveal GUN1 and GUN5-dependent signals as a source for the regulation of genes involved in anthocyanin biosynthesis. The signal transduction cascade includes well-known transcription factors for the control of anthocyanin biosynthesis, which are deregulated in gun mutants. We propose that regulation of PHANGs and genes contributing to anthocyanin biosynthesis are two, albeit oppositely, co-regulated processes during plastid biogenesis. [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]

Background: Human papillomavirus (HPV) is a causative agent for tonsillar and base of tongue squamous cell carcinoma (TSCC/BOTSCC), as well as for cervical cancer. Premalignant stages in cervical cancer have been studied extensively, while little is known about premalignant stages in TSCC/BOTSCC and the role of HPV. Here we analyzed differences in gene and protein expression between high‐grade dysplasia and invasive cancer in both HPV‐positive (HPV+) and HPV‐negative (HPV−) TSCC/BOTSCC. Methods: High‐grade dysplasia and invasive carcinoma were laser microdissected from HPV+ and HPV− TSCC/BOTSCC tumor sections. Differential gene expression was studied utilizing nanoString RNA‐panels and genes of interest were validated on the protein level by immunohistochemistry. Results: Forty genes in the HPV+ tumors showed significantly different expression between high‐grade dysplasia and invasive cancer and 33 genes in the HPV− tumors. Five out of the nine most significant pathways showed similar increased activity in invasive cancer as compared to high‐grade dysplasia in both HPV+ and HPV− tumors. Lastly, significant differences in protein expression was confirmed for SPARC, psoriasin, type I collagen and galectin‐1 in both HPV+ and HPV− tumors. Conclusions: This is to our knowledge the first study disclosing differences and similarities in gene expression between dysplastic and invasive HPV+ and HPV− TSCC/BOTSCC. [ABSTRACT FROM AUTHOR]

Fractionation effects and the formation of structured domains are investigated in polydisperse systems of attractive spherocylinders with the help of Monte Carlo simulations. For sufficiently high attractive interaction strength and pressure, the large rods in the system aggregate and form a highly ordered hexatic monolayer that coexists with an isotropic fluid of smaller rods. Fractionation diminishes with decreasing interaction strength but is still observed for hard rod systems, in which the large rods form a nematic droplet rather than a monolayer. Results for polydisperse systems are accompanied by phase diagrams for monodisperse systems of attractive spherocylinders. Here, the phase behavior is shown as a function of rod length and pressure. [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]

5-Aminolevulinic acid (ALA) is the first stable, committed metabolic intermediate of the tetrapyrrole biosynthesis pathway. The different classes of tetrapyrrole end-products, such as chlorophyll, heme, phycobilins, and siroheme, fulfill pivotal functions in photosynthetic organisms and are required in different quantities during the daily environmental changes and the entire plant development. As result of the light-absorbing characteristics of tetrapyrroles as well as their redox properties as oxidants and reductants, the biosynthetic pathway requires safety precautions to ensure a continuous flow of metabolites and to prevent accumulation of excessive light-absorbing end-products, intermediates, and breakdown products. ALA synthesis is the rate-limiting step of tetrapyrrole biosynthesis and is controlled by tight light-dark and environmental-dependent regulatory mechanisms at the transcriptional and post-translational level. In this chapter, we summarize several post-translational control mechanisms of ALA synthesis, mainly on glutamyl-tRNA reductase, the first enzyme of tetrapyrrole biosynthesis, which ensure a partially coinciding regulation for the adequate supply of metabolic precursors for the synthesis of tetrapyrroles in plants. [ABSTRACT FROM AUTHOR]

For more than 2 decades, satellite observations from instruments such as GOME, SCIAMACHY, GOME-2, and OMI have been used for the monitoring of bromine monoxide (BrO) distributions on global and regional scales. In October 2017, the TROPOspheric Monitoring Instrument (TROPOMI) was launched on board the Copernicus Sentinel-5 Precursor platform with the goal of continuous daily global trace gas observations with unprecedented spatial resolution. In this study, sensitivity tests were performed to find an optimal wavelength range for TROPOMI BrO retrievals under various measurement conditions. From these sensitivity tests, a wavelength range for TROPOMI BrO retrievals was determined and global data for April 2018 as well as for several case studies were retrieved. Comparison with GOME-2 and OMI BrO retrievals shows good consistency and low scatter of the columns. The examples of individual TROPOMI overpasses show that due to the better signal-to-noise ratio and finer spatial resolution of 3.5×7 km2 , TROPOMI BrO retrievals provide good data quality with low fitting errors and unique information on small-scale variabilities in various BrO source regions such as Arctic sea ice, salt marshes, and volcanoes. [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]

For more than two decades, satellite observations from instruments such as GOME, SCIAMACHY, GOME-2 and OMI have been used for the monitoring of bromine monoxide (BrO) distributions on global and regional scales. In October 2017, the TROPOspheric Monitoring Instrument (TROPOMI) was launched onboard the Copernicus Sentinel-5 Precursor platform with the goal of continuous daily global trace gas observations with unprecedented spatial resolution. In this study, sensitivity tests were performed to find an optimal wavelength range for TROPOMI BrO retrievals under various measurement conditions. From these sensitivity tests, a wavelength range for TROPOMI BrO retrievals was determined and global data for April 2018 as well as for several case studies were retrieved. Comparison with GOME-2 and OMI BrO retrievals shows good consistency and low scatter of the columns. The examples of individual TROPOMI overpasses show that due to the better signal to noise ratio and finer spatial resolution of 3.5x7km2, TROPOMI BrO retrievals provide good data quality with low fitting errors and unique information on small scale variabilities in various BrO source regions such as Arctic sea ice, salt marshes, and volcanoes. [ABSTRACT FROM AUTHOR]

In order to maintain enzyme stability and activity, chloroplasts use two systems of thiol‐disulfide reductases for the control of redox‐dependent properties of proteins. Previous studies have revealed that plastid‐localized thioredoxins (TRX) and the NADPH‐dependent thioredoxin reductase C (NTRC) are important for the reduction of cysteine residues of enzymes involved in chlorophyll synthesis. Very recently, it was shown that the pale green phenotype of the ntrc mutant is suppressed when the contents of 2‐cysteine peroxiredoxins (2CP) A and B are decreased. Here, we show that suppression of the ntrc phenotype results from a recovery of wild‐type‐like redox control of chlorophyll biosynthesis enzymes in ntrc/2cp mutants. The presented results support the conclusion that TRXs rather than NTRC are the predominant reductases mediating the redox‐regulation of these enzymes. [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]

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]

We examine public policy toward the use of genetic information by insurers. Individuals engage in unobservable primary prevention and have access to different prevention technologies. Thus, insurance markets are affected by moral hazard and adverse selection. Individuals can choose to take a genetic test to acquire information about their prevention technology. Information has positive decision-making value, that is, individuals may adjust their behavior based on the result of the test. However, testing also exposes individuals to uncertainty over the available insurance contract, so-called classification risk, which lowers the value of information. In our analysis we distinguish between four different policy regimes, determine the value of information under each regime and associated equilibrium outcomes on the insurance market. We show that the policy regimes can be Pareto ranked, with a duty to disclose being the preferred regime and an information ban the least preferred one. [ABSTRACT FROM AUTHOR]

Ice-surface elevation profiles of more than 30 000 km in total length are derived from kinematic GNSS (GPS and the Russian GLONASS) observations on sledge convoy vehicles along traverses between Vostok Station and the East Antarctic coast. These profiles have accuracies between 4 and 9 cm. They are used to validate elevation data sets from both radar and laser satellite altimetry as well as four digital elevation models. A crossover analysis with three different processing versions of Envisat radar altimetry elevation profiles yields a clear preference for the relocation method over the direct method of slope correction and for threshold retrackers over functional fit algorithms. The validation of CryoSat-2 low-resolution mode and SARIn mode data sets documents the progress made from baseline B to C elevation products. ICESat laser altimetry data are demonstrated to be accurate to a few decimetres over a wide range of surface slopes. A crossover adjustment in the region of subglacial Lake Vostok combining ICESat elevation data with our GNSS profiles yields a new set of ICESat laser campaign biases and provides new, independent evidence for the stability of the ice-surface elevation above the lake. The evaluation of the digital elevation models reveals the benefits of combining laser and radar altimetry. [ABSTRACT FROM AUTHOR]

GENOMES UNCOUPLED 4 (GUN4) is a positive regulator of light-dependent chlorophyll biosynthesis. GUN4 activates Mg chelatase (MgCh) that catalyzes the insertion of an Mg2+ ion into protoporphyrin IX. We show that Arabidopsis (Arabidopsis thaliana) GUN4 is phosphorylated at Ser 264 (S264), the penultimate amino acid residue at the C terminus. While GUN4 is preferentially phosphorylated in darkness, phosphorylation is reduced upon accumulation of Mg porphyrins. Expression of a phosphomimicking GUN4(S264D) results in an incomplete complementation of the white gun4-2 null mutant and a chlorotic phenotype comparable to gun4 knockdown mutants. Phosphorylated GUN4 has a reduced stimulatory effect on MgCh in vitro and in vivo but retains its protein stability and tetrapyrrole binding capacity. Analysis of GUN4 found in oxygenic photosynthetic organisms reveals the evolution of a C-terminal extension, which harbors the phosphorylation site of GUN4 expressed in angiosperms. Homologs of GUN4 from Synechocystis and Chlamydomonas lack the conserved phosphorylation site found in a C-terminal extension of angiosperm GUN4. Biochemical studies proved the importance of the C-terminal extension for MgCh stimulation and inactivation of GUN4 by phosphorylation in angiosperms. An additional mechanism regulating MgCh activity is proposed. In conjunction with the dark repression of 5-aminolevulinic acid synthesis, GUN4 phosphorylation minimizes the flow of intermediates into the Mg branch of the tetrapyrrole metabolic pathway for chlorophyll biosynthesis. [ABSTRACT FROM AUTHOR]

In chloroplasts, protein phosphorylation regulates important processes, including metabolism, photosynthesis, gene expression, and signaling. Because the hitherto known plastid protein kinases represent only a fraction of existing kinases, we aimed at the identification of novel plastid-localized protein kinases that potentially phosphorylate enzymes of the tetrapyrrole biosynthesis (TBS) pathway. We screened publicly available databases for proteins annotated as putative protein kinase family proteins with predicted chloroplast localization. Additionally, we analyzed chloroplast fractions which were separated by sucrose density gradient centrifugation by mass spectrometry. We identified four new candidates for protein kinases, which were confirmed to be plastid localized by expression of GFP-fusion proteins in tobacco leaves. A phosphorylation assay with the purified kinases confirmed the protein kinase activity for two of them. [ABSTRACT FROM AUTHOR]

For the development of advanced driving assistance and automation systems the simulation plays an important role. Urban areas get increasing emphasis, especially in the context of future Car2X-communication. This article describes an approach developed in the project Virtual World. Its goal is to model such virtual three-dimensional (3D) environments and logical road descriptions automatically based on a tool chain from heterogeneous geographic datasets (e.g., cadastral data, road surveying, aerial pictures, and crowd-sourced data). As proof of concept, the urban area of Braunschweig, Germany, was chosen. The article focuses on the generation of a 3D city model with corresponding road network description suitable for driving and traffic simulations as used in research and industry. The article gives technical descriptions of the major work steps and discusses issues regarding the availability of data. It concludes with the current project outcome and further development in the project. [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]

Redox regulation is an essential post-translational regulatory mechanism in prokaryotes and eukaryotes. The reversible oxidation and reduction of cysteine residues of proteins is also important in photosynthetic organisms to control enzymatic activities, protein stability and the interaction with other proteins of chloroplast-localized proteins. Several enzymes of the plant tetrapyrrole biosynthesis pathway have been identified to be redox regulated by thioredoxins (TRXs) and NADPH-dependent thioredoxin reductase C (NTRC). Among these proteins, Mg protoporphyrin IX methyltransferase (encoded by CHLM) was identified to be activated and stabilized by interaction with NTRC. CHLM catalyzes a methyl group transfer by using S-adenosylmethionine (SAM). Here we demonstrate that three conserved cysteine residues of Arabidopsis CHLM are essential for catalytic function and redox-dependent activation of the enzyme. In vitro and in planta biochemical assays of recombinant CHLM and the Arabidopsis chlm knockout mutant overexpressing wild-type and cysteine substitution mutants of CHLM revealed modified methyltransferase activity, when the conserved cysteine residues of CHLM are replaced by serine. While C177 is responsible for redox-dependent enzyme activation, exchange of the two cysteine residues, C111 and C115, has a strong impact on enzyme activity. The modified CHLM activity of single and double mutants with cysteine substitution is presented, and the role of each cysteine residue is discussed based on a modeled structure of CHLM. These studies contribute to enhanced understanding of the physiological and enzymatic significance of redoxregulated CHLM. [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]

During 2009 - 2011, we reported that the oral and cervical prevalence of human papillomavirus (HPV) was high by international standards at 9.3% and 74%, respectively, in youth aged 15 - 23 years attending a youth clinic in Stockholm. After gradual introduction of public HPV vaccination during 2007 - 2012, between 2013 and 2014, when 73% of the women were HPV-vaccinated, but not necessarily before their sexual debut, oral HPV prevalence had dropped to 1.4% as compared with 9.3% in 2009 - 2011 (p 0.00001). Cervical HPV prevalence was high and common cervical high-risk types were HPV51, 56, 59, 73, 16, 39, 52, and 53. However, it was shown that HPV16, 31, and 70 were significantly less common among HPV-vaccinated women than among those who had not received the vaccine. [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]

The use of biodegradable materials for implants is a promising strategy to overcome known long-term clinical complications related to permanent implants. Ideally, biodegradable implants support the damaged tissue for a certain period and then degrade, while the physiological function of the surrounding tissue is restored. Although Mg-based alloys nearly ideally lend themselves to biodegradable implants, a few critical shortcomings promoted the development of alternative alloy systems. Due to their reasonably good biocompatibility, moderate corrosion rate without hydrogen evolution and adequate mechanical properties, increasing attention has been paid to Zn alloys. In this work, precipitation-hardening alloys in the system Zn-Ag-Cu were developed relying on thermodynamic calculations. After casting the alloys, their microstructures were refined by thermomechanical treatment. The processing was tracked and directed, respectively, by routine investigations of the microstructure, associated with hardness assessments. Although microstructure refinement increased the hardness, the material proved to be susceptible to aging as the homologous temperature of zinc is at 0.43 Tm. Besides mechanical performance and corrosion rate, long-term mechanical stability is another crucial factor that must be taken into consideration to ensure the safety of the implant and thus requires a profound understanding of the aging process. [ABSTRACT FROM AUTHOR]

Inland ships are an important source of NOx , especially for cities along busy waterways. The amount and effect of such emissions depend on the traffic density and NOx emission rates of individual vessels. Ship emission rates are typically derived using in situ land measurements in relation to NOx emission factors (e.g. the number of pollutants emitted by ships per unit of burnt fuel). In this study, a different approach is taken, and NOx emission rates are obtained (in gs-1). Within the EU LIFE project, CLean INland SHipping (CLINSH), a new approach to calculating the NOx emission rates from data of in situ measurement stations has been developed and is presented in this study. Peaks (i.e. elevated concentrations) of NOx were assigned to the corresponding source ships, using the AIS (automated identification system) signals they transmit. Each ship passage was simulated, using a Gaussian puff model, in order to derive the emission rate of the respective source ship. In total, over 32 900 ship passages have been monitored over the course of 4 years. The emission rates of NOx were investigated with respect to ship speed, ship size, and direction of travel. Comparisons of the onshore-derived emission rates and those on board for selected CLINSH ships show good agreement. The derived emission rates are of a similar magnitude to emission factors from previous studies. Most ships comply with existing limits due to grandfathering. The emission rates (in gs-1) can be directly used to investigate the effect of ship traffic on air quality, as the absolute emitted number of pollutants per unit of time is known. In contrast, for relative emission factors (in gkg-1 fuel), further knowledge about the fuel consumption of the individual ships is needed to calculate the number of pollutants emitted per unit of time. [ABSTRACT FROM AUTHOR]

The newly developed lexsyg system by Freiberg Instruments is a versatile luminescence reader, suited for research on the luminescence of materials, fundamental research in luminescence dating, but also for routine mass measurements in retrospective dosimetry as well as in dating application. The 80 sample storage wheel is disconnected from the measurement chamber and therefore crosstalk of optical stimulation is absent and cross-irradiation is negligible from the α- and β-sources, which are providing very uniform irradiations, with the latter especially designed for radiofluores-cence (RF) measurement. Optical excitation sources and filter wheels to vary detection wavelengths can be programmed to change at almost any time within measurement sequences, including the auto-mated change of an optional wheel holding up to four different detectors. Thermoluminescence meas-urements and preheating are possible with a versatile heater, which can be programmed for linear or non-linear heating or cooling, as well as holding a temperature constant. Rates as well as durations can be varied, together with individual ramping, staging and cooling for an almost unlimited number of steps. Violet- and IR-lasers, green and blue LED-arrays can be operated in continuous (CW) or modulated mode (linear/non-linear), and optionally for pulsed as well as time resolved luminescence detection. Six arrays of power LEDs allow the simulation of different bleaching regimes ('solar simu-lator'), while luminescence detection can be achieved by a variety of photomultiplier tubes and by CCD cameras for spatially resolved measurements and luminescence spectra. [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]

Simple Summary: To better prevent/combat recurrence and identify predictive/targetable markers upon diagnosis, we performed whole-exome sequencing (WES) of primary tumours and relapses of human papillomavirus positive (HPV+) tonsillar and base of tongue cancer (TSCC/BOTSCC) on patients treated with curative intent, with and without relapse. A specific deletion in the CDC27 gene was observed only in the primaries of 5/17 patients that recurred but in none of the 18 patients without recurrence. Furthermore, three specific variants and 26 mutated genes enriched in mucins were identified in at least 30% of all primaries irrespective of recurrence. To conclude, a specific CDC27 deletion could be specific for recurrent HPV+ TSCC/BOTSCC, while BCLAF1, AQP7 and other globally mutated genes could be of significance for further investigation. To identify predictive/targetable markers in human papillomavirus positive (HPV+) tonsillar and base of tongue cancer (TSCC/BOTSCC), whole-exome sequencing (WES) of tumours of patients with/without recurrence was performed. Forty primary tumours and adjacent normal tissue were separated by micro-dissection from formalin-fixed paraffin-embedded tissue from patients treated with curative intent 2000–2014 at Karolinska University Hospital. Successful sequencing was obtained in primary tumours of 18 patients without and primaries of 17 with local or distant recurrence, as well as in 10 corresponding recurrences (i.e., five local relapses and five distant metastases) from these 17 patients. One variant—a high-impact deletion in the CDC27 gene—was observed only in primaries of 5/17 patients that had a recurrence after full treatment but in none of those without recurrence. In addition, 3 variants and 26 mutated genes, including CDC27, BCLAF1 and AQP7, were present in at least 30% of all primary tumours independent of prognosis. To conclude, a CDC27 deletion was specific and found in ~30% of samples from patients with a local relapse/distant metastasis and could, therefore, potentially be a prospective marker to predict prognosis. Commonly mutated genes, such as BCLAF1, should be further studied in the context of targeted therapy. [ABSTRACT FROM AUTHOR]

We present the application of Latent Semantic Analysis (LSA) in combination with recommender systems, in order to enhance discovery in geoportals. As a basis for discovery, metadata of spatial data and services, as well as of non-spatial resources, such as documents and scientific papers, is created and registered in the catalogue of the geoportal (semi-)automatically. Links that are not inherent in the data itself are established based on the semantic similarity of its textual content using LSA. This leads to the transition from unstructured data to structured (metadata) information, serving as a basis for the generation of knowledge. The metadata information is integrated into a recommendation system that provides a ranked list showing (1) what other users viewed and (2) the related resources discovered by the LSA workflow as a result. Based on the assumptions that similar texts have something in common and that users are likely to be interested in what other users viewed, recommendations provide a broader, but also more precise, search result; on the one hand, the recommender engine considers additional information; on the other hand, it ranks resources based on the discovery experience of other users and the likeliness of the documents being related to each other. [ABSTRACT FROM AUTHOR]

The NADPH-dependent thioredoxin reductase C (NTRC) is involved in redox-related regulatory processes in chloroplasts and nonphotosynthetic active plastids. Together with 2-cysteine peroxiredoxin, it forms a two-component peroxide-detoxifying system that acts as a reductant under stress conditions. NTRC stimulates in vitro activity of magnesium protoporphyrin IX monomethylester (MgPMME) cyclase, most likely by scavenging peroxides. Reexamination of tetrapyrrole intermediate levels of the Arabidopsis (Arabidopsis thaliana) knockout ntrc reveals lower magnesium protoporphyrin IX (MgP) and MgPMME steady-state levels, the substrate and the product of MgP methyltransferase (CHLM) preceding MgPMME cyclase, while MgP strongly accumulates in mutant leaves after 5-aminolevulinic acid feeding. The ntrc mutant has a reduced capacity to synthesize 5-aminolevulinic acid and reduced CHLM activity compared with the wild type. Although transcript levels of genes involved in chlorophyll biosynthesis are not significantly altered in 2-week-old ntrc seedlings, the contents of glutamyl-transfer RNA reductase1 (GluTR1) and CHLM are reduced. Bimolecular fluorescence complementation assay confirms a physical interaction of NTRC with GluTR1 and CHLM. While ntrc contains partly oxidized CHLM, the wild type has only reduced CHLM. As NTRC also stimulates CHLM activity in vitro, it is proposed that NTRC has a regulatory impact on the redox status of conserved cysteine residues of CHLM. It is hypothesized that a deficiency of NTRC leads to a lower capacity to reduce cysteine residues of GluTR1 and CHLM, affecting the stability and, thereby, altering the activity in the entire tetrapyrrole synthesis pathway. [ABSTRACT FROM AUTHOR]

Inthis work, the behavior of a 200-μm spherical carbon particlemoving in a hot environment mainly consisting of O2andCO2was investigated numerically. The main goal of thiswork was to study the influence of the particle velocity, temperature,and composition of the surrounding gas on the carbon consumption rates.The particle investigated was placed in a uniform oxygen/carbon dioxidemixture at different Reynolds numbers corresponding to different laminarflow regimes. The ambient temperature was systematically varied inthe range of 1000–3000 K, and the mass fraction of O2was varied between 0.12 and 0.36. To solve the Navier–Stokesequations for the flow field coupled with the energy and species conservationequations, a finite volume solver was applied. In addition to thesolid carbon, the model incorporates six gaseous chemical species(O2, CO, CO2, H2, H2O,and N2). The semiglobal reaction mechanism includes theforward and backward water–gas-shift reaction, one reactionfor CO combustion, and four heterogeneous reactions. The ambient mediumwas assumed to be nearly dry (YH2O= 0.001). The numerical results were carefully validatedagainst experimental data published in the literature (Bejaranoand Levendis, Combust. Flame2008, 153, 270−287). In particular,it was shown that taking into account losses from radiation (gas–gas,gas–solid) brings the results closer to the experimental data.Additionally, the influence of the gas–gas radiation effecton the integral characteristics of the oxidizing particle was studied.In particular, the results are discussed with a focus on the systematicvariation of the ambient-gas temperature and Reynolds number. We foundout that increasing the Reynolds number enhances species transportto the particle surface and shifts particle oxidation from a diffusion-controlledto a kinetically controlled regime. [ABSTRACT FROM AUTHOR]

A high-order interior penalty discontinuous Galerkin method for the compressible Navier-Stokes equations is introduced, which is a modification of the scheme given by Hartmann and Houston. In this paper we investigate the influence of penalization and boundary treatment on accuracy. By observing eigenvalues and condition numbers, a lower bound for the penalization term μ was found, whereas convergence studies depict reasonable upper bounds and a linear dependence on the critical time step size. By investigating conservation properties we demonstrate that different boundary treatments influence the accuracy by several orders of magnitude, and propose reasonable strategies to improve conservation properties. [ABSTRACT FROM AUTHOR]

Cold acclimation is a multigenic process by which many plant species increase their freezing tolerance. Stabilization of photosynthesis and carbohydrate metabolism plays a crucial role in cold acclimation. To study regulation of primary and secondary metabolism during cold acclimation of Arabidopsis thaliana, metabolic mutants with deficiencies in either starch or flavonoid metabolism were exposed to 4°C. Photosynthesis was determined together with amounts of carbohydrates, anthocyanins, organic acids and enzyme activities of the central carbohydrate metabolism. Starch deficiency was found to significantly delay soluble sugar accumulation during cold acclimation, while starch overaccumulation did not affect accumulation dynamics but resulted in lower total amounts of \sucrose and glucose. Anthocyanin amounts were lowered in both starch deficient and overaccumulating mutants. Vice versa, flavonoid deficiency did not result in a changed starch amount, which suggested a unidirectional signalling link between starch and flavonoid metabolism. Mathematical modelling of carbon metabolism indicated kinetics of sucrose biosynthesis to be limiting for carbon partitioning in leaf tissue during cold exposure. Together with cold‐induced dynamics of citrate, fumarate and malate amounts, this provided evidence for a central role of sucrose phosphate synthase activity in carbon partitioning between biosynthetic and dissimilatory pathways which stabilizes photosynthesis and metabolism at low temperature. Summary Statement: Regulation at the interface of plant primary and secondary metabolism during cold acclimation was analysed by kinetic modelling. Our findings suggest that cold‐induced limitation of sucrose biosynthesis regulates substrate availability for the coordinated accumulation of starch and anthocyanins. [ABSTRACT FROM AUTHOR]

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]

This work is devoted to the numerical investigation of heat and fluid flow past a sphere with a centric, cylindrical bore. Such spherical rings are of interest in many technologi-cal processes. In chemical reactors, for example, spherical rings are used as a catalyst with an increased reacting surface. Motivated by this fact, we considered spherical rings with different bores and different orientations in flow regimes corresponding to Reynolds numbers from 10 up to 300. The results show a significant influence of the bore diameter on the symmetry and hence the steadiness of the flow field. The Nusselt number can be increased, which leads to a moderate rise in the drag coefficient. Thereby, the effect of the borehole depends on the Reynolds number, the bore diameter, and the angle of attack. For that reason, drag forces and total heat transfers do not simply follow the heat exchanging surface area. Based on the presented results, new correlations are given for both the drag coefficient and the Nusselt number; correlations which incorporate the bore geometry and the bore orientation in the flow field. [ABSTRACT FROM AUTHOR]

In ultra-wideband (UWB) wireless propagation channels, each multipath component (MPC) can exhibit delay dispersion or, equivalently, frequency dependence; even more, this dispersion can be different for different MPCs. While this effect is understood to have important implications for UWB system design, extraction of the frequency-dependence parameters from measurements has been lacking. This paper will provide both the theoretical tools for the parameter extraction, and provide experimental results of such parameters in UWB indoor channels. We first develop a method that extracts a single MPC. Based on the image principle, the method identifies locations and intensity of radio sources including both original and image sources (corresponding to MPCs) by a distributed antenna array. We show that the method provides spatial resolution better than 0.5 m and is robust against possible measurement errors. Having applied the method to the measured channels in indoor line-of-sight scenarios, we track the detected image sources over (partially overlapping) frequency subbands to obtain frequency dependent properties of their intensity and location. The variation of the source intensity over the frequency was found to be significant. Furthermore, the locations of the image sources can vary as the frequency changes. Comparison of the results with models that do not describe varying per-path frequency dependence revealed noticeable difference in the shape of the CIRs, and as a result, in the delay spread and the number of significant delay bins for Rake reception. [ABSTRACT FROM PUBLISHER]

In this paper, algorithms for joint high-resolution direction-of-arrival (DoA) and polarization estimation using real-world arrays with imperfections are proposed. Both azimuth and elevation angles are considered. Partially correlated and coherent signals may be handled as well. Unlike most of the work available in the open literature, we consider the case when polarization sensitive antenna arrays, which may be disposed on a conformal surface, may have unknown (but fixed) geometries, be composed of elements with individual beampatterns and be subject to cross-polarization as well as mounting platform effects. Herein, recent results on steering vector modeling from noise-corrupted array calibration measurements are employed. This allows for incorporating all nonidealities of an antenna array into the estimation algorithms in a general and convenient manner. The proposed estimators can be implemented using the fast Fourier transform or polynomial rooting techniques regardless of the array configuration. The stochastic Cramér–Rao lower bound for the estimation problem at hand is established using the results from array steering vector modeling as well. The proposed expression takes into account array nonidealities, making such a bound tight even for real-world arrays. Extensive simulation results are provided using several real-world antenna arrays. The proposed algorithms outperform conventional algorithms available in the literature and have a performance close to the stochastic Cramér–Rao lower bound. [ABSTRACT FROM AUTHOR]