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Drought is a serious constraint on crop growth and production of important staple crops such as maize. Improved understanding of the responses of crops to drought can be incorporated into cropping system models to support crop breeding, varietal selection, and management decisions for minimizing negative impacts. We investigate the impacts of different soil types (stony and silty) and water regimes (irrigated and rainfed) on hydraulic linkages between soil and plant, as well as root : shoot growth characteristics. Our analysis is based on a comprehensive dataset measured along the soil–plant–atmosphere pathway at field scale in two growing seasons (2017 and 2018) with contrasting climatic conditions (low and high vapor pressure deficit). Roots were observed mostly in the topsoil (10–20 cm) of the stony soil, while more roots were found in the subsoil (60–80 cm) of the silty soil. The difference in root length was pronounced at silking and harvest between the soil types. Total root length was 2.5–6 times higher in the silty soil than in the stony soil with the same water treatment. At silking time, the ratios of root length to shoot biomass in the rainfed plot of the silty soil (F2P2) were 3 times higher than those in the irrigated silty soil (F2P3), while the ratio was similar for two water treatments in the stony soil. With the same water treatment, the ratios of root length to shoot biomass of silty soil were higher than for stony soil. The seasonally observed minimum leaf water potential (ψleaf) varied from around -1.5 MPa in the rainfed plot in 2017 to around -2.5 MPa in the same plot of the stony soil in 2018. In the rainfed plot, the minimum ψleaf in the stony soil was lower than in the silty soil from -2 to -1.5 MPa in 2017, respectively, while these were from -2.5 to -2 MPa in 2018, respectively. Leaf water potential, water potential gradients from soil to plant roots, plant hydraulic conductance (Ksoil_plant), stomatal conductance, transpiration, and photosynthesis were considerably modulated by the soil water content and the conductivity of the rhizosphere. When the stony soil and silt soil are compared, the higher "stress" due to the lower water availability in the stony soil resulted in fewer roots with a higher root tissue conductance in the soil with more stress. When comparing the rainfed with the irrigated plot in the silty soil, the higher stress in the rainfed soil resulted in more roots with a lower root tissue conductance in the treatment with more stress. This illustrates that the "response" to stress can be completely opposite depending on conditions or treatments that lead to the differences in stress that are compared. To respond to water deficit, maize had higher water uptake rate per unit root length and higher root segment conductance in the stony soil than in the silty soil, while the crop reduced transpired water via reduced aboveground plant size. Future improvements in soil–crop models in simulating gas exchange and crop growth should further emphasize the role of soil textures on stomatal function, dynamic root growth, and plant hydraulic system together with aboveground leaf area adjustments. [ABSTRACT FROM AUTHOR]

Dietary supplements play a reactive role in the human body; they perform the role of signaling molecules, which are important for the immune system, expression, and regulation of signal pathways. Conversely, depending on many parameters such as age, physical activity duration, training condition, intensity, and genetic summary can be a reason for the amassing and overproduction of oxidants/anti-oxidants, leading to muscle distress and structural impairment. The research was based on primary data analysis to determine whether the study used SPSS and AMOS software and generated results between them. Additionally, many sports happen in pre-seasons, and athletes have their training session on the same day, which leads to the formation of nitrogen and Oxygen reactive and inflammatory constituents. Therefore, there is a need for some ways to reduce these effects and increase the performance and recovery of athletes. There is an existing indication that using dietary supplements and dietary sources like fruits, cereals, and vegetables can reduce oxidative stress, post-exercise swelling, and immune defects and improve metabolic recovery and strength of muscles, thus all advantageous to what sports and athletes demand. Overall, the result was a direct and significant impact of dietary supplements on physical performance and muscle recovery. [ABSTRACT FROM AUTHOR]

The first example of intramolecular nucleophilic addition of 1,4-diazabutatriene to ester is disclosed. This approach provides a facile and versatile synthesis for functionalized 2H-1,4-benzoxazines under metal-, reagent-, and solvent-free conditions. Experimental and computational studies revealed the pivotal role of 1,5-acyl migration as the self-catalytic step in the reaction selectivity. [ABSTRACT FROM AUTHOR]

Herein, we present an efficient and atom‐economic tandem hydroformylation organocatalyzed Friedel‐Crafts reaction sequence for the synthesis of diindolylmethanes. Classic syntheses have relied on (Lewis) acid activation of aldehydes, which are often not commercially available and rather sensitive in handling. In contrast, the combination of rhodium‐catalyzed hydroformylation and subsequent organocatalytic activation of the in‐situ formed aldehydes allows the use of readily available and stable alkenes with various functional groups while avoiding acidic conditions to expand the range of available diindolylmethanes. A broad scope of diindolylmethanes was prepared in yields up to 85 % demonstrates the utility of the presented method. [ABSTRACT FROM AUTHOR]

This review examines the role of defective carbon‐based electrodes in sodium‐ion and vanadium flow batteries. Methods for introducing defects into carbon structures are explored and their effectiveness in improving electrode performance is demonstrated. In sodium‐based systems, research focuses primarily on various precursor materials and heteroatom doping to optimise hard carbon electrodes. Defect engineering increases interlayer spacing, porosity, and changes the surface chemistry, which improves sodium intercalation and reversible capacities. Heteroatom functionalisation and surface modification affect solid electrolyte interface formation and coulombic efficiencies. For flow batteries, post‐fabrication electrode enhancement methods produce defects to improve electrode kinetics, although these methods often introduce oxygen functional groups as well, making isolation of defect effects difficult. Continued research efforts are key to developing carbon‐based electrodes that can meet the unique challenges of future battery systems. [ABSTRACT FROM AUTHOR]

Herein, a highly efficient five‐step reaction sequence to BODIPYs is presented. The key step is the combination of transition metal‐catalyzed in‐situ generation of aldehydes and their subsequent organocatalytic activation to yield dipyrromethanes, which are further converted to the corresponding BODIPY. Classic syntheses towards BODIPYs have relied on aldehydes or acid chlorides, which are often not commercially available and rather sensitive to handle. The presented approach starts from readily available and stable alkenes or aryl‐bromides, which allows to extend the range of readily available BODIPYs that can be tailored for their specific use. The synthesis of 55 derivatives with overall yields of up to 78 % demonstrates the wide applicability and advantages of the presented method. [ABSTRACT FROM AUTHOR]

In plant science, it is an established method to obtain structural parameters of crops using image analysis. In recent years, deep learning techniques have improved the underlying processes significantly. However, since data acquisition is time and resource consuming, reliable training data are currently limited. To overcome this bottleneck, synthetic data are a promising option for not only enabling a higher order of correctness by offering more training data but also for validation of results. However, the creation of synthetic data is complex and requires extensive knowledge in Computer Graphics, Visualization and High-Performance Computing. We address this by introducing Synavis , a framework that allows users to train networks on real-time generated data. We created a pipeline that integrates realistic plant structures, simulated by the functional–structural plant model framework CPlantBox, into the game engine Unreal Engine. For this purpose, we needed to extend CPlantBox by introducing a new leaf geometrization that results in realistic leafs. All parameterized geometries of the plant are directly provided by the plant model. In the Unreal Engine, it is possible to alter the environment. WebRTC enables the streaming of the final image composition, which, in turn, can then be directly used to train deep neural networks to increase parameter robustness, for further plant trait detection and validation of original parameters. We enable user-friendly ready-to-use pipelines, providing virtual plant experiment and field visualizations, a python-binding library to access synthetic data and a ready-to-run example to train models. [ABSTRACT FROM AUTHOR]

Drought is a serious constraint to crop growth and production of important staple crops such as maize. Improved understanding of the responses of crops to drought can be incorporated into cropping system models to support crop breeding, varietal selection and management decisions for minimizing negative impacts. We investigate the impacts of different soil types (stony and silty) and water regimes (irrigated and rainfed) on hydraulic linkages between soil and plant, as well as root: shoot growth characteristics. Our analysis is based on a comprehensive dataset measured along the soil-plant-atmosphere pathway at field scale in two growing seasons (2017, 2018) with contrasting climatic conditions (low and high VPD). Roots were observed mostly in the topsoil (10-20 cm) of the stony soil while more roots were found in the subsoil (60-80 cm) of the silty soil. The difference in root length was pronounced at silking and harvest between the soil types. Total root length was 2.5 - 6 times higher in the silty soil compared to the stony soil with the same water treatment. At silking time, the ratios of root length to shoot biomass in the rainfed plot of the silty soil (F2P2) were 3 times higher than those in the irrigated silty soil (F2P3) while the ratio was similar for two water treatments in the stony soil. With the same water treatment, the ratios of root length to shoot biomass of silty soil was higher than stony soil. The observed minimum leaf water potential (ψleaf) varied from around -1.5 MPa in the rainfed plot in 2017 to around -2.5 MPa in the same plot of the stony soil in 2018. In the rainfed plot, the mimimum ψleaf in the stony soil was lower than in silty soil from -2 to -1.5 MPa in 2017, respectively while these were from -2.5 to -2 MPa in 2018, respectively. Leaf water potential, water potential gradients from soil to plant roots, plant hydraulic conductance (Ksoil_plant), stomatal conductance, transpiration, and photosynthesis were considerably modulated by the soil water content and the conductivity of the rhizosphere. When the stony soil and silt soil are compared, the higher 'stress' due to the lower water availability in the stony soil resulted in less roots with a higher root tissue conductance in the soil with more stress. When comparing the rainfed with the irrigated plot in the silty soil, the higher stress in the rainfed soil resulted in more roots with a lower root tissue conductance in the treatment with more stress. This illustrates that the 'response' to stress can be completely opposite depending on conditions or treatments that lead to the differences in stress that are compared. To respond to water deficit, maize had higher water uptake rate per unit root length and higher root segment conductance in the stony soil than in the silty soil, while the crop reduced transpired water via reduced aboveground plant size. Future improvements of soil-crop models in simulating gas exchange and crop growth should further emphasize the role of soil textures on stomatal function, dynamic root growth, and plant hydraulic system together with aboveground leaf area adjustments. [ABSTRACT FROM AUTHOR]

Non‐invasive imaging of processes within the soil–plant continuum, particularly root and soil water distributions, can help optimize agricultural practices such as irrigation and fertilization. In this study, in‐situ time‐lapse horizontal crosshole ground penetrating radar (GPR) measurements and root images were collected over three maize crop growing seasons at two minirhizotron facilities (Selhausen, Germany). Root development and GPR permittivity were monitored at six depths (0.1–1.2 m) for different treatments within two soil types. We processed these data in a new way that gave us the information of the "trend‐corrected spatial permittivity deviation of vegetated field," allowing us to investigate whether the presence of roots increases the variability of GPR permittivity in the soil. This removed the main non‐root‐related influencing factors: static influences, such as soil heterogeneities and rhizotube deviations, and dynamic effects, such as seasonal moisture changes. This trend‐corrected spatial permittivity deviation showed a clear increase during the growing season, which could be linked with a similar increase in root volume fraction. Additionally, the corresponding probability density functions of the permittivity variability were derived and cross‐correlated with the root volume fraction, resulting in a coefficient of determination (R2) above 0.5 for 23 out of 46 correlation pairs. Although both facilities had different soil types and compaction levels, they had similar numbers of good correlations. A possible explanation for the observed correlation is that the presence of roots causes a redistribution of soil water, and therefore an increase in soil water variability. Core Ideas: Analying spatial and temporal belowground GPR signal variability and root images for maize crop roots.Root images and GPR data show differences for different treatments.Linking of root volume fraction and GPR permittivity variability. [ABSTRACT FROM AUTHOR]

Herein we report an improved self‐assembling phosphorus ligand based on hydrogen bonding between pyridone/hydroxypyridine in the ligand backbone. The N‐pyrrolyl substituents significantly improve the π‐backbonding properties of the ligand. Rhodium, iridium and platinum complexes of the ligand were prepared and analyzed by NMR spectroscopy and x‐ray crystal structure analysis. A catalyst based on this ligand showed very high catalytic activity and linear regioselectivity in rhodium‐catalyzed hydroformylation of 1‐octene. The same ligand was applied in linear regioselective iridium‐catalyzed hydroformylation of 1‐octene. [ABSTRACT FROM AUTHOR]

The Pd‐catalyzed Suzuki‐Miyaura cross‐couplings (SMRs) are utilized as the most practical method to construct C−C bond, especial for biaryls. However, a major disadvantage of current protocols is the requirement of excess organoboron coupling partner (1.5–3.0 equiv.). Herein, a novel palladacyclic 1,3‐bis(2,6‐diisopropylphenyl)acenaphthoimidazol‐2‐ylidene (AnIPr) precatalyst possessing a chiral oxazoline was designed, which enabled a general protocol towards bulky tri‐ortho‐substituted biaryls, ternaphthalenes and diarylanthracenes via the Pd‐catalyzed SMR employing equimolar organoborons and aryl bromides. A remarkable scope of substrates with various functional groups and heterocycles were well compatible with an adaptability to synthesize useful ligands. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons, such as pyrenes, are a well‐known material class for non‐covalent modification of carbon surfaces in many applications. In electrochemical energy storage, pyrenes are mostly used in large polymeric structures. This work addresses the use of carboxy‐ and amino‐functionalized pyrenes for graphite electrodes for lithium‐ion batteries (LIBs). Pyrenes are explored as adsorbed species on graphite prior to electrode fabrication and as additives to the electrode composition. Thereby, 1‐pyrenecarboxylic acid, 1‐pyrenebutyric acid, 1‐aminopyrene, and 1‐pyrenebutylamine were under investigation. As additives, pyrenes do not influence the cycling performance of the electrode at low current but deteriorate the performance at high current, regardless of the functional group. However, when the pyrenes are adsorbed to the graphite surface, the influence of the different functional groups becomes clearly visible, revealing that an additional butyl group has a positive impact on the cycling performance and lithium‐ion transport of the electrodes. Electrodes with 1‐pyrenebutyric acid even enhanced the performance compared to the pristine electrode. [ABSTRACT FROM AUTHOR]

The kinetic processes responsible for the efficient oxidation of dissolved vanadyl oxide species in the positive half‐cell of a vanadium flow battery are far from being understood. Despite recent evidence that the reaction is most strongly favored at hydrogen‐terminated graphite edge sites, a mechanism involving oxygen‐containing surface groups has still been frequently reproduced to date. In this work, operando Raman spectroscopy follows the reaction at the interface between graphite‐based model electrodes and vanadium‐containing sulfuric acid as the electrolyte. The potential‐dependent growth of different vibrational modes is related to the electrocatalytic activity of the sample and allows to track the oxidation of the electrolyte species. Moreover, the results express vanadium reaction intermediates of dimeric origin only on the edge‐exposed surface of graphite, which exhibits significantly higher electrochemical activity. No interaction with surface oxygen postulated before could be observed for the active electrodes at potentials relevant to the reaction. Instead, a new growing graphite‐related feature shows direct electronic interactions between vanadium ions and carbon atoms during charge transfer. [ABSTRACT FROM AUTHOR]

Detailed mechanistic investigations on our previously reported synthesis of branched allylic esters by the rhodium complex‐catalyzed propargylic C−H activation have been carried out. Based on initial mechanistic studies, we present herein more detailed investigations of the reaction mechanism. For this, various analytical (NMR, X‐ray crystal structure analysis, Raman) and kinetic methods were used to characterize the formation of intermediates under the reaction conditions. The knowledge obtained by this was used to further optimize the previous conditions and generate a more active catalytic system. [ABSTRACT FROM AUTHOR]

Despite the growing interest in brain–machine interface (BMI)-driven neuroprostheses, the translation of the BMI output into a suitable control signal for the robotic device is often neglected. In this article, we propose a novel control approach based on dynamical systems that was explicitly designed to take into account the nature of the BMI output that actively supports the user in delivering real-valued commands to the device and, at the same time, reduces the false positive rate. We hypothesize that such a control framework would allow users to continuously drive a mobile robot and it would enhance the navigation performance. 13 healthy users evaluated the system during three experimental sessions. Users exploit a 2-class motor imagery BMI to drive the robot to five targets in two experimental conditions: with a discrete control strategy, traditionally exploited in the BMI field, and with the novel continuous control framework developed herein. Experimental results show that the new approach: 1) allows users to continuously drive the mobile robot via BMI; 2) leads to significant improvements in the navigation performance; and 3) promotes a better coupling between user and robot. These results highlight the importance of designing a suitable control framework to improve the performance and the reliability of BMI-driven neurorobotic devices. [ABSTRACT FROM AUTHOR]

Accurate detection of pathological conditions in human subjects can be achieved through off-line analysis of recorded biological signals such as electrocardiograms (ECGs). However, human diagnosis is time-consuming and expensive, as it requires the time of medical professionals. This is especially inefficient when indicative patterns in the biological signals are infrequent. Moreover, patients with suspected pathologies are often monitored for extended periods, requiring the storage and examination of large amounts of non-pathological data, and entailing a difficult visual search task for diagnosing professionals. In this work we propose a compact and sub-mW low power neural processing system that can be used to perform on-line and real-time preliminary diagnosis of pathological conditions, to raise warnings for the existence of possible pathological conditions, or to trigger an off-line data recording system for further analysis by a medical professional. We apply the system to real-time classification of ECG data for distinguishing between healthy heartbeats and pathological rhythms. Multi-channel analog ECG traces are encoded as asynchronous streams of binary events and processed using a spiking recurrent neural network operated in a reservoir computing paradigm. An event-driven neuron output layer is then trained to recognize one of several pathologies. Finally, the filtered activity of this output layer is used to generate a binary trigger signal indicating the presence or absence of a pathological pattern. We validate the approach proposed using a Dynamic Neuromorphic Asynchronous Processor (DYNAP) chip, implemented using a standard 180 nm CMOS VLSI process, and present experimental results measured from the chip. [ABSTRACT FROM AUTHOR]

This article discusses a new methodology for the synthesis of highly fluorescent meso-alkyl and -aryl BODIPYs, which are important compounds in the field of chemistry. The method involves the use of a stainless steel autoclave to perform key steps, including the generation of aldehydes and their subsequent activation. The resulting dipyrromethanes are then converted to BODIPYs with high yields. The article provides more detailed information on the research and can be found in the Chemistry - A European Journal. [Extracted from the article]

Background/Aims: To date, there is no imaging technique to assess tubular function in vivo. Blood oxygen level-dependent magnetic resonance imaging (BOLD MRI) measures tissue oxygenation based on the transverse relaxation rate (R2*). The present study investigates whether BOLD MRI can assess tubular function using a tubule-specific pharmacological maneuver. Methods: Cross sectional study with 28 participants including 9 subjects with ATNinduced acute kidney injury (AKI), 9 healthy controls, and 10 subjects with nephron sparing tumor resection (NSS) with clamping of the renal artery serving as a model of ischemia/reperfusion (I/R)-induced subclinical ATN (median clamping time 15 min, no significant decrease of eGFR, p=0.14). BOLD MRI was performed before and 5, 7, and 10 min after intravenous administration of 40 mg furosemide. Results: Urinary neutrophil gelatinaseassociated lipocalin was significantly higher in ATN-induced AKI and NSS subjects than in healthy controls (p=0.03 and p=0.01, respectively). Before administration of furosemide, absolute medullary R2*, cortical R2*, and medullary/cortical R2* ratio did not significantly differ between ATN-induced AKI vs. healthy controls and between NSS-I/R vs. contralateral healthy kidneys (p>0.05 each). Furosemide led to a significant decrease in the medullary and cortical R2* of healthy subjects and NSS contralateral kidneys (p<0.05 each), whereas there was no significant change of R2* in ATN-induced AKI and the NSS-I/R kidneys (p>0.05 each). Conclusion: BOLD-MRI is able to detect even mild tubular injury but necessitates a tubulespecific pharmacological maneuver, e.g. blocking the Na+-K+-2Cl- transporter by furosemide. [ABSTRACT FROM AUTHOR]

Contract KAT2 will altogether produce about 8.6 m. t of excavated material. Most of this will be used as fill for various purposes or processed as aggregates for concrete production. This article deals with the management of the material excavated from the tunnel and of material, which has been affected by ground improvement measures or could have been contaminated during excavation or transport. Causes for chemical problems and risks with waste are identified, and possibilities and solutions for technically correct recycling or disposal in compliance with the conditions of waste management law are presented. As an example, the influence of selected additives such as cement or resin foam is discussed. There is also a description of investigation results into the evidence that high concentrations occur in the determination of iron and aluminium in the eluate. These parameters are of significance for the recycling of rock since they are limited under the Austrian federal waste management plan (BAWP). Im Baulos KAT2 fallen insgesamt rund 8,6 Mio. t Tunnelausbruchmaterial an. Der überwiegende Teil wird als Schüttmaterial mit unterschiedlichen Verwendungen verwertet oder für die Herstellung von Gesteinskörnungen zur Betonherstellung aufbereitet. Dieser Beitrag behandelt den Umgang mit Tunnelausbruchmaterial und mit Material, das durch gebirgsverbessernde Maßnahmen beeinflusst wird oder das im Löseprozess und dem Transport verunreinigt werden kann. Ursachen für abfallchemische Auffälligkeiten und Risiken werden aufgezeigt; Möglichkeiten und Lösungen für die fachgerechte Verwertung oder Beseitigung unter Einhaltung abfallrechtlicher Rahmenbedingungen werden vorgestellt. Exemplarisch wird der Einfluss ausgewählter Hilfsstoffe wie Zement oder Harzschaum diskutiert. Beschrieben werden auch Untersuchungsergebnisse zum Nachweis, dass bei der Bestimmung von Eisen und Aluminium im Eluat hohe Konzentrationen auftreten. Diese Parameter sind für die Verwertung des Gesteins von Bedeutung, weil sie nach Bundesabfallwirtschaftsplan (BAWP) begrenzt sind. [ABSTRACT FROM AUTHOR]

Silk fibers are well known for their mechanical propertiessuchas strength and toughness and are lightweight, making them an interestingmaterial for a variety of applications. Silk mechanics mainly relyon the secondary structure of the underlying proteins. Lacewing eggstalk silk proteins obtain a cross-β structure with individualβ strands aligned perpendicular to the fiber axis. This structureis in contrast with that of silks of spiders or silkworms with βstrands parallel to the fiber axis and to that of silks of honeybeeswith α helices arranged in coiled coils. On the basis of thecross-β structure the mechanical properties of egg stalks aredifferent from those of other silks concerning extensibility, toughness,and bending stiffness. Here we show the influence of relative humidityon the mechanical behavior of lacewing egg stalks and propose a modelbased on secondary structure changes to explain the differences ona molecular level. At low relative humidity, the stalks rupture atan extension of 3%, whereas at high relative humidity the stalks ruptureat 434%. This dramatic increase corresponds to breakage of hydrogenbonds between the β strands and a rearrangement thereof in aparallel-β structure. [ABSTRACT FROM AUTHOR]