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Drought is a serious agronomic problem, and urgent attention to overcome drought stress is vital to eradicate or minimize its effects on crop production. Random induction of genomic mutation is a technique that can enhance genetic diversity leading to useful traits such as enhanced drought tolerance. In this study, sugarcane callus was exposed to different concentrations of the chemical mutagen, ethyl methanesulfonate (EMS). Concentrations of 20 mM and lower were identified as useful to induce genomic mutations without compromising in vitro sugarcane plant regeneration abilities. Furthermore, sugarcane callus was exposed to varying concentrations of polyethylene glycol (PEG) for different time periods in order to identify a suitable in vitro osmotic selection regime to simulate drought stress in vitro. The optimal in vitro osmotic selection treatment was identified as callus exposed to 20% (w/v) PEG6000 for 8 weeks, followed by a 2 weeks osmotic recovery period without PEG and ending with a further 8 week PEG selection period during somatic embryo regenerations. Sugarcane callus from the NCo310 cultivar was subsequently mutagenized with 16 mM EMS and in vitro selected on 20% (w/v) PEG6000, which resulted in the survival of 18 plantlets. These in vitro selected lines were subjected to preliminary greenhouse pot trials to confirm drought tolerance. Pot trials identified seven lines that outlived NCo310 control plants. In addition, when re-watered after the drought stress period, plants from one mutant line recovered and were able to form new shoots. The results from this study indicate, therefore, that EMS mutagenesis and in vitro selection for osmotic pressure using PEG can be successfully applied to cultivate sugarcane plants with improved morphological and physiological responses to water stress. [ABSTRACT FROM AUTHOR]

Co–Al–W-based alloys are promising new materials for high-temperature applications. They owe their high-temperature strength to hardening by ternary L1 2 -Co 3 (Al 1−x W x ) precipitates, which may form even though binary Co 3 Al is not stable. In the current work, density functional theory calculations are performed to study the solubility and ordering of the transition metals W, Mo, Ti, and Ta at the Al sublattice in L1 2 -Co 3 Al. The sublattice disorder is modelled with a newly parametrised cluster expansion and compared to results using special quasi-random structures. Our results for W and Mo show that the mixing energy exhibits a minimum at approximately x = 0.7. However, the computed small values of the mixing energies indicate that W and Mo atoms are fully disordered with the Al atoms already at low temperatures. For Ti and Ta we find no sizeable driving force for ordering with the Al atoms. The computed solubilities on the Al sublattice obtained are in the range of 40–80 meV/atom for W and Mo and less than 25 meV/atom for Ti and Ta. [ABSTRACT FROM AUTHOR]

Most applications of thermodynamic databases to materials design are limited to ambient pressure. The consideration of elastic contributions to thermodynamic stability is highly desirable but not straight-forward to realise. We present examples of existing physical models for pressure-dependent thermodynamic functions and discuss the requirements for future implementations given the existing results of experiments and first-principles calculations. We briefly summarize the calculation of elastic constants and point out examples of nonlinear variation with pressure, temperature and chemical composition that would need to be accounted for in thermodynamic databases. This is particularly the case if a system melts from different phases at different pressures. Similar relations exist between pressure and magnetism and hence set the need to also include magnetic effects in thermodynamic databases for finite pressure. We present examples to illustrate that the effect of magnetism on stability is strongly coupled to pressure, temperature, and external fields. As a further complication we discuss dynamical instabilities that may appear at finite pressure. While imaginary phonon frequencies may render a structure unstable and destroy a crystal lattice, the anharmonic effects may stabilize it again at finite temperature. Finally, we also outline a possible implementation scheme for strain effects in thermodynamic databases. [ABSTRACT FROM AUTHOR]

Abstract A full-length cDNA encoding cytosolic phosphoglycerate mutase (PGAM; E.C. 5.4.2.1) from potato (Solanum tuberosum L.) was isolated. RNA blots indicated that the accumulation of PGAM transcript was similar in all organs studied. Transgenic potato plants with either constitutive, or tuber-specific, decreases in PGAM expression were created. Constitutive reduction of enzyme activity of down to 25% of the control resulted in increased 3-PGA contents of up to 30% in leaves, but also led to reduced growth rates, probably due to a reduction of photosynthetic activity. Soluble carbohydrates and starch in leaves were reduced, and the tuber yield of the plants was lowered. Plants with 30% of the wild-type PGAM activity in leaves and 55% in tubers showed reduced amounts of starch in tubers also. Tuber-specific reduction of PGAM expression in transgenic potato plants had no effect on starch metabolism and tuber yield, although the 3-PGA level was increased. This indicates that 3-PGA concentrations in potato tubers are not important for regulating ADP-glucose pyrophosphorylase activity in the production of starch under some environmental conditions. [ABSTRACT FROM AUTHOR]

Unlabelled: The relationships between both diarrhoea and respiratory infections and linear and ponderal growth were prospectively examined among 28 753 Sudanese pre-school children. Childhood infections were significantly and inversely associated with attained height and attained weight and gain in height and weight over a 6-mo period. They were significantly and positively associated also with stunting after adjusting for age, gender, socio-economic status, dietary variables and previous morbidity. Attained height was on average 17 mm lower (95% CI [-19 -15]) for children with diarrhoea and 11 mm lower (95% CI [-3 -9]) for children with complicated cough than for those without these symptoms. The association between morbidity and attained weight was significant for diarrhoea and complicated cough, but the differences between children with and without symptoms were negligible. The risk of being stunted 6 mo later was 1.38 times (95% CI [1.20 1.59]), 1.29 times (95% CI [0.97 1.72]) and 1.32 times (95% CI [1.13 1.54]) greater among normally-nourished children with diarrhoea, febrile diarrhoea and fever, respectively, than among children without these symptoms. The difference in attained height between children with diarrhoea or complicated cough and those without symptoms increased with age, and was larger among the non-breastfed children compared with breastfed children.Conclusion: The results underline the need to reduce child morbidity to prevent the impairment of growth and development. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents sugar and organic acid content and composition, the principal determinants of flavour, of strawberries of the cultivars Festival and Ventana at four consecutive developmental stages. The metabolite profiles of these two cultivars were very similar. Glucose was the predominant sugar at approximately twice the concentration of fructose and sucrose. Total acid concentrations were five times lower than total sugar concentrations in ripe berries, with citrate comprising roughly two thirds of the total acid content. The maximum extractable catalytic activities of key enzymes in the relevant metabolic pathways were also quantified during berry development, in an attempt to elucidate possible correlations. Sucrose synthase activity was very low or undetected, while neutral invertase activity was relatively high, suggesting that sucrose synthase does not make a significant contribution to sink strength in these cultivars. Three enzymes, invertase, pyrophosphate-dependent phosphofructokinase (PFP) and fructose-1,6-bisphosphatase (FBPase), showed distinct activity patterns during development and may affect sugar and acid accumulation and sugar composition of strawberries. [Copyright &y& Elsevier]

Abstract: The metabolite profiles of Sutherlandia frutescens populations may vary depending on their geographical location, affecting the quality of plant-based pharmaceutical products generated from this species. This paper aims at using metabolic profiling through liquid chromatography mass spectrometry (LC–MS) to assess the metabolite content of seed pods from populations of the medicinal plant S. frutescens growing in geographically different environments. Terpenoid (retention time: 7.5–9.0min) and flavonoid (retention time: 15.0–19.0min) regions of the chromatograms were useful in distinguishing between samples and five distinct clusters were revealed after principal component analysis (PCA). This may assist in tracing the region where plants actually come from and the identification at the subspecies level. To increase the class separation and simplify interpretation, we focused on those populations from the arid Karoo and the coastal Gansbaai area, applying orthogonal partial least squares discriminant analysis (OPLS-DA) to organize these into two clear groups. The presence or absence of sutherlandioside B (SU1) and its derivatives contributed significantly to the separation of the Karoo plants from those from the Gansbaai cluster. Processing procedures of herbal products require standardization, but this becomes challenging when plants do not contain key chemical principles. Extracts from the Gansbaai population had virtually undetectable levels of SU1; consequently products manufactured from farmed plants originating from this region may lack these compounds, which are now proposed to be anti-cancerous. There were several sutherlandioside-type metabolites that distinguished populations from each other. These chemicals may add new knowledge in terms of the broader metabolomic understanding of Sutherlandia populations and their potential pharmacological action. In vitro plants generated as part of a commercialization–conservation strategy had a similar metabolite profile to non-propagated plants. In fact, these plants could be traced to the West Coast populations, further confirming their identity. This study highlighted that SU1 cannot be used as the only quality control marker for Sutherlandia products, since it does not occur in all populations and there is no conclusive evidence that it is the main active ingredient of the plant. The effect of α-naphthalene acetic acid (NAA) at 1mg l−1 was tested on in vitro plants. Sutherlandiosides and sutherlandins were detectable in treated plants. Although the treatment had impacts on the growth capacity of plants, SU1 did not accumulate at higher levels in auxin-treated plantlets. The similarity of micropropagated plants to wild plants proved that tissue culture does not have deleterious effects on the chemistry of Sutherlandia plants. Metabolomic approaches using LC–MS are thus an important feature as a diagnostic tool and should be integrated into the herbal product manufacturing process utilizing Sutherlandia and its extracts. [Copyright &y& Elsevier]

Acrolein is highly toxic and its presence in wine has been correlated with the development of bitterness. Analytical detection and quantification in aqueous solutions are challenging due to high reactivity and problems with chemical derivative analysis. Here we demonstrate the potential of a natural derivative, formed under conditions prevailing in wine, as a marker for acrolein detection. Solid-phase microextraction (SPME) coupled with gas chromatograph mass spectrometry (GC-MS) was validated as a technique for direct detection of the acrolein dimer. Conventional GC-MS analysis using a quadrupole mass spectrometer did not provide sufficient chromatographic resolution for the separation of the target analyte from interfering compounds. Accurate mass measurements with time-of-flight (TOF)-MS, on the other hand, allowed qualitative and quantitative measurements of the acrolein dimer. This work lays the analytical foundation for studies on the evolution of acrolein and its dimer in solution. [ABSTRACT FROM AUTHOR]

Understanding how water interacts with nanopores of carbonaceous electrodes is crucial for energy storage and conversion applications. A high surface area of carbonaceous materials does not necessarily need to translate to a high electrolyte-solid interface area. Herein, we study the interaction of water with nanoporous C1N1 materials to explain their very low specific capacity in aqueous electrolytes despite their high surface area. Water was used to probe chemical environments, provided by pores of different sizes, in 1H MAS NMR experiments. We observe that regardless of their high hydrophilicity, only a negligible portion of water can enter the nanopores of C1N1, in contrast to a reference pure carbon material with a similar pore structure. The common paradigm that water easily enters hydrophilic pores does not apply to C1N1 nanopores below a few nanometers. Calorimetric and sorption experiments demonstrated strong water adsorption on the C1N1 surface, which restricts water mobility across the interface and impedes its penetration into the nanopores., (© 2024 Wiley‐VCH GmbH.)

Self-templating is a facile strategy for synthesizing porous carbons by direct pyrolysis of organic metal salts. However, the method typically suffers from low yields (<4%) and limited specific surface areas (SSA<2000 m 2  g -1 ) originating from low activity of metal cations (e.g., K + or Na + ) in promoting construction and activation of carbon frameworks. Here we use cesium acetate as the only precursor of oxo-carbons with large SSA of the order of 3000 m 2  g -1 , pore volume approaching 2 cm 3  g -1 , tunable oxygen contents, and yields of up to 15 %. We unravel the role of Cs + as an efficient promoter of framework formation, templating and etching agent, while acetates act as carbon/oxygen sources of carbonaceous frameworks. The oxo-carbons show record-high CO 2 uptake of 8.71 mmol g -1 and an ultimate specific capacitance of 313 F g -1 in the supercapacitor. This study helps to understand and rationally tailor the materials design by a still rare organic solid-state chemistry., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

In two studies, we examined whether open science practices, such as making materials, data, and code of a study openly accessible, positively affect public trust in science. Furthermore, we investigated whether the potential trust-damaging effects of research being funded privately (e.g. by a commercial enterprise) may be buffered by such practices. After preregistering six hypotheses, we conducted a survey study (Study 1; N  = 504) and an experimental study (Study 2; N  = 588) in two German general population samples. In both studies, we found evidence for the positive effects of open science practices on trust, though it should be noted that in Study 2, results were more inconsistent. We did not however find evidence for the aforementioned buffering effect. We conclude that while open science practices may contribute to increasing trust in science, the importance of making use of open science practices visible should not be underestimated.

Carbon suboxide (C 3 O 2 ) is a unique molecule able to polymerize spontaneously into highly conjugated light-absorbing structures at temperatures as low as 0 °C. Despite obvious advantages, little is known about the nature and the functional properties of this carbonaceous material. In this work, the aim is to bring "red carbon," a forgotten polymeric semiconductor, back to the community's attention. A solution polymerization process is adapted to simplify the synthesis and control the structure. This allows one to obtain this crystalline covalent material at low temperatures. Both spectroscopic and elemental analyses support the chemical structure represented as conjugated ladder polypyrone ribbons. Density functional theory calculations suggest a crystalline structure of AB stacks of polypyrone ribbons and identify the material as a direct bandgap semiconductor with a medium bandgap that is further confirmed by optical analysis. The material shows promising photocatalytic performance using blue light. Moreover, the simple condensation-aromatization route described here allows the straightforward fabrication of conjugated ladder polymers and can be inspiring for the synthesis of carbonaceous materials at low temperatures in general., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

The preparation of stable and efficient electrocatalysts comprising abundant and non-critical row-materials is of paramount importance for their industrial implementation. Herein, we present a simple synthetic route to prepare Mn(II) sub-nanometric active sites over a highly N-doped noble carbonaceous support. This support not only promotes a strong stabilization of the Mn(II) sites, improving its stability against oxidation, but also provides a convenient coordination environment in the Mn(II) sites able to produce CO, HCOOH and CH 3 COOH from electrochemical CO 2 reduction.

Hypothesis: Developing materials for thermally driven adsorption chillers and adsorption heat pumps is a growing research field due to the potential of these technologies to address up to 50% of the world's total energy demand. These materials must be abundant, easy to synthesize, hydrophilic, and low in cost. Bare carbon materials are hydrophobic and therefore usually not considered for these applications. However, by introducing heteroatoms and tuning their porosity, the hydrophilicity of carbonaceous networks can be increased significantly., Experimental: Herein, a series of highly nitrogen doped carbonaceous materials (CNs) have been synthesized by submitting uric acid to heat treatment at different temperatures in the presence of an inorganic salt mix as solvent and pore template. The effect of the thermal treatment on the materials composition, pore network, and water sorption capability has been studied., Findings: At 800 °C, a nitrogen depleted carbonaceous material with a maximal water uptake of 1.38g H2O g -1 is obtained. Condensation at 750 °C creates an ultra-hydrophilic CN with a water uptake of 0.8 g H2O g -1 at already much lower partial pressures. While the maximum uptake is mainly ascribed to the mesopore volume of the material, the differences in hydrophilicity can be controlled by functionality., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Trehalose is a non-reducing disaccharide widely distributed in nature. The trehalose biosynthetic intermediate, trehalose 6-phosphate (Tre6P) is an essential regulatory and signaling molecule involved in both regulation of carbon metabolism and photosynthesis. To investigate the effect of altered trehalose synthesis on sucrose accumulation in sugarcane ( Saccharum spp . hybrid), we independently overexpressed the Escherichia coli otsA (trehalose-6-phosphate synthase; TPS) and otsB (trehalose-6-phosphate phosphatase; TPP) genes and additionally partially silenced native TPS expression. In mature cane, sucrose levels in the otsA transgenic plants were lowered, whereas sucrose levels in the otsB transgenic plants were increased. Partial silencing of TPS expression in sugarcane transformed with a TPS-targeted microRNA recombinant construct was confirmed in leaf and mature internode tissue of transgenic plants. Most of the silencing transgenic lines accumulated trehalose at lower levels than the wild-type (WT) plants. The immature stalk tissue of these transgenic lines had lower levels of glucose and fructose, whereas the mature internode tissue had lower sucrose and glucose levels, when compared with the WT. Furthermore, various minor metabolites and sugars were detected in the sugarcane plants, which mostly decreased as the stalk tissue of the cane matured. The results demonstrate that manipulation of Tre6P/trehalose metabolism has the potential to modify the profile of soluble sugars accumulated in sugarcane stems., Competing Interests: The Authors did not report any conflict of interest., (© 2021 The Authors. Plant Direct published by American Society of Plant Biologists and the Society for Experimental Biology and John Wiley & Sons Ltd.)

Herein, the basic nature of noble covalent, sp2-conjugated materials prepared via direct condensation of guanine in the presence of an inorganic salt melt as structure directing agent was studied. At temperatures below 700 °C stable and more basic addition products with at C/N ratio of 1 (C 1 N 1 adducts) and with rather uniform micropore sizes were formed. Carbonization at higher temperatures broke the structural motif, and N-doped carbons with 11 wt % and surface areas of 1900 m 2  g -1 were obtained. The capability for CO 2 sorption and catalytic activity of the materials depended of both their basicity and their pore morphology. The optimization of the synthetic parameters led to very active (100 % conversion) and highly selective (99 % selectivity) heterogeneous base catalysts, as exemplified with the model Knoevenagel condensation of benzaldehyde with malononitrile. The high stability upon oxidation of these covalent materials and their basicity open new perspectives in heterogeneous organocatalysis., (© 2020 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

The role of starch degradation in non-vascular plants is poorly understood. To expand our knowledge of this area, we have studied this process in Physcomitrella patens. This has been achieved through examination of the step known to initiate starch degradation in angiosperms, glucan phosphorylation, catalysed by glucan, water dikinase (GWD) enzymes. Phylogenetic analysis indicates that GWD isoforms can be divided into two clades, one of which contains GWD1/GWD2 and the other GWD3 isoforms. These clades split at a very early stage within plant evolution, as distinct sequences that cluster within each were identified in all major plant lineages. Of the five genes we identified within the Physcomitrella genome that encode GWD-like enzymes, two group within the GWD1/GWD2 clade and the others within the GWD3 clade. Proteins encoded by both loci in the GWD1/GWD2 clade, named PpGWDa and PpGWDb, are localised in plastids. Mutations of either PpGWDa or PpGWDb reduce starch phosphate abundance, however, a mutation at the PpGWDa locus had a much greater influence than one at PpGWDb. Only mutations affecting PpGWDa inhibited starch degradation. Mutants lacking this enzyme also failed to develop gametophores, a phenotype that could be chemically complemented using glucose supplementation within the growth medium.

Starch is a plant storage polyglucan that accumulates in plastids. It is composed of two polymers, amylose and amylopectin, with different structures and plays several roles in helping to determine plant yield. In leaves, it acts as a buffer for night time carbon starvation. Genetically altered plants that cannot synthesize or degrade starch efficiently often grow poorly. There have been a number of successful approaches to manipulate leaf starch metabolism that has resulted in increased growth and yield. Its degradation is also a source of sugars that can help alleviate abiotic stress. In edible parts of plants, starch often makes up the majority of the dry weight constituting much of the calorific value of food and feed. Increasing starch in these organs can increase this as well as increasing yield. Enzymes involved in starch metabolism are well known, and there has been much research analyzing their functions in starch synthesis and degradation, as well as genetic and posttranslational regulatory mechanisms affecting them. In this mini review, we examine work on this topic and discuss future directions that could be used to manipulate this metabolite for improved yield.

The Co-Ta system has been reviewed and the thermodynamic description was re-assessed in the present work. DFT (density functional theory) calculations considering spin polarization were performed to obtain the energies for all end-member configurations of the C14, C15, C36 and μ phases for the evaluation of the Gibbs energies of these phases. The phase diagram calculated with the present description agrees well with the experimental and theoretical data. Considering the DFT results was essential for giving a better description of the μ phase at lower temperatures.

Cassava ( Manihot esculenta Crantz) is a root crop used as a foodstuff and as a starch source in industry. Starch functional properties are influenced by many structural features including the relative amounts of the two glucan polymers amylopectin and amylose, the branched structure of amylopectin, starch granule size and the presence of covalent modifications. Starch phosphorylation, where phosphates are linked either to the C3 or C6 carbon atoms of amylopectin glucosyl residues, is a naturally occurring modification known to be important for starch remobilization. The degree of phosphorylation has been altered in several crops using biotechnological approaches to change expression of the starch-phosphorylating enzyme GLUCAN WATER DIKINASE (GWD). Interestingly, this frequently alters other structural features of starch beside its phosphate content. Here, we aimed to alter starch phosphorylation in cassava storage roots either by manipulating the expression of the starch phosphorylating or dephosphorylating enzymes. Therefore, we generated transgenic plants in which either the wild-type potato GWD ( StGWD ) or a redox-insensitive version of it were overexpressed. Further plants were created in which we used RNAi to silence each of the endogenous phosphoglucan phosphatase genes STARCH EXCESS 4 ( MeSEX4 ) and LIKE SEX4 2 ( MeLSF ), previously discovered by analyzing leaf starch metabolism in the model species Arabidopsis thaliana . Overexpressing the potato GWD gene ( StGWD ), which specifically phosphorylates the C6 position, increased the total starch-bound phosphate content at both the C6 and the C3 positions. Silencing endogenous LSF2 gene ( MeLSF2 ), which specifically dephosphorylates the C3 position, increased the ratio of C3:C6 phosphorylation, showing that its function is conserved in storage tissues. In both cases, other structural features of starch (amylopectin structure, amylose content and starch granule size) were unaltered. This allowed us to directly relate the physicochemical properties of the starch to its phosphate content or phosphorylation pattern. Starch swelling power and paste clarity were specifically influenced by total phosphate content. However, phosphate position did not significantly influence starch functional properties. In conclusion, biotechnological manipulation of starch phosphorylation can specifically alter certain cassava storage root starch properties, potentially increasing its value in food and non-food industries.