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The authors previously developed a divide-and-conquer (DC)-based non-local excited-state calculation method for large systems using dynamical polarizability [Nakai and Yoshikawa, J. Chem. Phys. 146, 124123 (2017)]. This method evaluates the excitation energies and oscillator strengths using information on the dynamical polarizability poles. This article proposes a novel analysis of the previously developed method to obtain further configuration information on excited states, including excitation and de-excitation coefficients of each excitation configuration. Numerical applications to simple molecules, such as ethylene, hydrogen molecule, ammonia, and pyridazine, confirmed that the proposed analysis could accurately reproduce the excitation and de-excitation coefficients. The combination with the DC scheme enables both the local and non-local excited states of large systems with an excited nature to be treated. [ABSTRACT FROM AUTHOR]

The atmospheric reactions are mainly initiated by hydroxyl radical (OH). Here, we choose the C2H4 + OH reaction as a model reaction for other reactions of OH with alkenes. We use the GMM(P).L//CCSD(T)-F12a/cc-pVTZ-F12 theoretical method as the benchmark results close to the approximation of CCSDTQ(P)/CBS accuracy to investigate the C2H4 + OH reaction. The rate constants for the C2H4 + OH reaction at high-pressure limit were calculated by using the dual-level strategy. It integrates the transition state theory rate constant calculated by GMM(P).L//CCSD(T)-F12a/cc-pVTZ-F12 with the canonical variational transition state theory containing small-curvature tunneling (CVT/SCT) calculated by using the M11-L functional method with the MG3S basis set. The rate constants of C2H4 + OH at different pressures were obtained by using both the system-specific quantum Rice–Ramsperger–Kassel (SS-QRRK) theory and master equation method. The calculated results uncover that both the calculated rate constants at different pressures and temperatures are quantitatively consistent with the values obtained by the experimental measurements in the C2H4 + OH reaction. We find that the post-CCSD(T) contributions to the barrier height for the C2H4 + OH reaction are significant with the calculated value of −0.38 kcal/mol. We also find that the rate determining step is only dominated by the tight transition state under atmospheric conditions, whereas previous investigations indicated that the rate constants were controlled by both the loose and tight transition states in the C2H4 + OH reaction. The present findings unravel that it is an important factor for the effect of torsional anharmonicity on quantitative kinetics. [ABSTRACT FROM AUTHOR]

We simulate the nonadiabatic dynamics of photo-induced isomerization and dissociation in ethylene using ab initio classical trajectories in an extended phase space of nuclear and electronic variables. This is achieved by employing the linearized semiclassical initial value representation method for nonadiabatic dynamics, where discrete electronic states are mapped to continuous classical variables using either the Meyer–Miller–Stock–Thoss representation or a more recently introduced spin mapping approach. Trajectory initial conditions are sampled by constraining electronic state variables to a single initial excited state and by drawing nuclear phase space configurations from a Wigner distribution at a finite temperature. An ensemble of classical ab initio trajectories is then generated to compute thermal population correlation functions and analyze the mechanisms of isomerization and dissociation. Our results serve as a demonstration that this parameter-free semiclassical approach is computationally efficient and accurate, identifying mechanistic pathways in agreement with previous theoretical studies and also uncovering dissociation pathways observed experimentally. [ABSTRACT FROM AUTHOR]

The photodissociation dynamics of jet-cooled ethyl radical (C2H5) via the A ̃ 2A′(3s) states are studied in the wavelength region of 230–260 nm using the high-n Rydberg H-atom time-of-flight (TOF) technique. The H + C2H4 product channels are reexamined using the H-atom TOF spectra and photofragment translational spectroscopy. A prompt H + C2H4( X ̃ 1Ag) product channel is characterized by a repulsive translational energy release, anisotropic product angular distribution, and partially resolved vibrational state distribution of the C2H4( X ̃ 1Ag) product. This fast dissociation is initiated from the 3s Rydberg state and proceeds via a H-bridged configuration directly to the H + C2H4( X ̃ 1Ag) products. A statistical-like H + C2H4( X ̃ 1Ag) product channel via unimolecular dissociation of the hot electronic ground-state ethyl ( X ̃ 2A′) after internal conversion from the 3s Rydberg state is also examined, showing a modest translational energy release and isotropic angular distribution. An adiabatic H + excited triplet C2H4(ã3B1u) product channel (a minor channel) is identified by energy-dependent product angular distribution, showing a small translational energy release, anisotropic angular distribution, and significant internal excitation in the C2H4(ã3B1u) product. The dissociation times of the different product channels are evaluated using energy-dependent product angular distribution and pump–probe delay measurements. The prompt H + C2H4( X ̃ 1Ag) product channel has a dissociation time scale of <10 ps, and the upper bound of the dissociation time scale of the statistical-like H + C2H4( X ̃ 1Ag) product channel is <5 ns. [ABSTRACT FROM AUTHOR]

We present a Cu/PTFE electrode for the CO2 reduction reaction with a high coverage of *OH which facilitates both the activation of CO2 and the C–C coupling, leading to a faradaic efficiency for ethylene exceeding 50% at an exceptionally low potential of −246 mV vs. RHE, with the maximum FEC2H4 reaching 60.3%. [ABSTRACT FROM AUTHOR]

In order to realize stable propagation of the ethylene-air rotating detonation wave with less velocity deficit in the annular combustion chamber, a series of experiments have been carried out while changing the combustor width (i.e. 10 mm, 15 mm, 25 mm, and a hollow combustor), mass flow rate of air, and equivalence ratio. The air and ethylene are supplied into the combustor through a slot-orifice impinging injection scheme, where air is injected through a slot with a height of 0.5 mm and ethylene is supplied by 160 orifices with a diameter of 0.35 mm. Experimental results indicate that four propagation modes have been obtained, i.e. the single wave mode, the sawtooth wave mode, the periodic oscillation mode, and the deflagration mode. The sawtooth wave mode and the periodic oscillation mode are considered unstable modes. In the single wave mode, the average propagation velocity of rotating detonations in the annular combustion chamber with a combustor width of 15 mm is between 1121 and 1215 m/s. The minimum velocity deficit is 21.9%, and the relative standard deviation of the propagation velocity is less than 5%, which is much lower than the experimental results of other studies utilizing ethylene and air in the annular combustors. In addition, the reasons may lead to the failure of producing rotating detonations have been analyzed. The effects of the chemical reactivity on the generation of rotating detonation waves have been demonstrated by installing a convergent nozzle at the exit of the combustor. [ABSTRACT FROM AUTHOR]

Adsorptive C2H2/C2H4 separation using metal–organic frameworks (MOFs) has emerged as a promising technology for the removal of C2H2 (acetylene) impurity (1 %) from C2H4 (ethylene). The practical application of these materials involves the optimization of separation performance as well as development of scalable and green production protocols. Herein, we report the efficient C2H2/C2H4 separation in a MOF, Cu(OH)INA (INA: isonicotinate) which achieves a record C2H2 packing density of 351 mg cm−3 at 0.01 bar through high affinity towards C2H2. DFT (density functional theory) calculations reveal the synergistic binding mechanism through pore confinement and the oxygen sites in pore wall. The weakly basic nature of binding sites leads to a relatively low heat of adsorption (Qst) of approximately 36 kJ/mol, which is beneficial for material regeneration and thermal management. Furthermore, a scalable and environmentally friendly synthesis protocol with a high space‐time yield of 544 kg m−3 day−1 has been developed without using any modulating agents. This material also demonstrates enduring separation performance for multiple cycles, maintaining its efficacy after exposure to water or air for three months. [ABSTRACT FROM AUTHOR]

Loss of Lon1 led to stunted plant growth and accumulation of nuclear‐encoded mitochondrial proteins including Lon1 substrates. However, an in‐depth label‐free proteomics quantification of mitochondrial proteins in lon1 revealed that the majority of mitochondrial‐encoded proteins decreased in abundance. Additionally, we found that lon1 mutants contained protein aggregates in the mitochondrial that were enriched in metabolic enzymes, ribosomal subunits and PPR‐containing proteins of the translation apparatus. These mutants exhibited reduced general mitochondrial translation as well as deficiencies in RNA splicing and editing. These findings support the role of Lon1 in maintaining a functional translational apparatus for mitochondrial‐encoded gene translation. Transcriptome analysis of lon1 revealed a mitochondrial unfolded protein response reminiscent of the mitochondrial retrograde signalling dependent on the transcription factor ANAC017. Notably, lon1 mutants exhibited transiently elevated ethylene production, and the shortened hypocotyl observed in lon1 mutants during skotomorphogenesis was partially alleviated by ethylene inhibitors. Furthermore, the short root phenotype was partially ameliorated by introducing a mutation in the ethylene receptor ETR1. Interestingly, the upregulation of only a select few target genes was linked to ETR1‐mediated ethylene signalling. Together this provides multiple steps in the link between loss of Lon1 and signalling responses to restore mitochondrial protein homoeostasis in plants. Summary statement: Plant Lon1 prevents the aggregation of mitochondrial proteins, including metabolic enzymes and components of the translational apparatus such as ribosomal and PPR proteins. Dysfunctional proteins within these aggregates inhibit the translation of mitochondrial‐encoded genes and trigger unfolded protein responses associated with ANAC017. [ABSTRACT FROM AUTHOR]

To preserve the quality traits of late-harvested 'Galaxy' apples during extended storage, the effects of 1-methylcyclopropene (1-MCP) treatment and storage conditions on postharvest quality were analysed. Alongside quality measures, indicators like ethylene production, respiration rate, aminocyclopropane-1-carboxylic acid oxidase (ACO) activity, and membrane permeability were assessed. Apples were harvested at an optimal harvest date or later and stored for 7 months at 1°C under regular atmosphere or controlled atmosphere. Treatments with 1–MCP at 300, 600 or 900 nL L−1 were applied pre- or post-storage. After 7 days shelf-life, apples subjected to 1-MCP and controlled atmosphere exhibited reduced ethylene production, respiration rate, and ACO activity compared to untreated or regular atmosphere counterparts. While the time of 1-MCP application and its concentration did not impact the respiration rate during shelf-life, controlled atmosphere effectively decreased it. The combination of controlled atmosphere and 1–MCP pre-storage was most effective in lowering ACO activity. Irrespective of conditions, 1-MCP curtailed ethylene production, respiration rate, and ACO activity during shelf-life, alleviating firmness and acidity loss. Only controlled atmosphere preserved quality and minimised disorders for optimally harvested apples, not late-harvested ones. None of the treatments maintained late-harvested apples' quality after long-term storage plus shelf-life. [ABSTRACT FROM AUTHOR]

Biosynthesis of the phytoalexins scopoletin and scopolin in Nicotiana species is regulated by upstream signals including jasmonate (JA), ethylene (ET), and NaWRKY3 in response to the necrotrophic fungus Alternaria alternata , which causes brown spot disease. However, how these signals are coordinated to regulate these phytoalexins remains unknown. By analyzing RNA sequencing data and RNAi, we identified NaERF1B-like (NaERF1B-L) as a key player in Nicotiana attenuata during A. alternata infection by regulating the transcripts of Feruloyl-CoA 6'-hydroxylase 1 (NaF6'H1), encoding a key enzyme for scopoletin biosynthesis, and NaVS1-like (NaVS1-L), a putative biosynthetic gene of the phytoalexin solavetivone. We further demonstrated that the synergistic induction of these two genes by JA and ET signaling is mediated by NaERF1B-L. Additionally, we found that the two closely related proteins, NaWRKY6 and NaWRKY3, physically interact to enhance NaERF1B-L expression by directly binding to and activating the NaERF1B-L promoter. Collectively, our current results demonstrate that NaERF1B-L plays a positive role in resistance to A. alternata by modulating phytoalexin biosynthesis through the integration of JA/ET and NaWRKY6/3 signaling. Our findings reveal a fine-tuned transcriptional regulatory hierarchy mediated by NaERF1B-L for brown spot disease resistance in wild tobacco. [ABSTRACT FROM AUTHOR]

Low‐Density Polyethylene (LDPE) reactors have the potential for rupture because of thermal runaway from auto‐accelerating chemistry. Pockets of unmixed, highly reactive, LDPE constituents, called hot spots, are often generated by conditions within the reactor and are the main source of thermal runaway. Because of this, there is a need to define thresholds of hot spot conditions that produce runaway. Computational Fluid Dynamics is used to study an isolated LDPE sphere with varying initial temperature, initial catalyst concentration, and volume to determine which combinations promote thermal runaway. It is found that increasing both initial temperature and initial catalyst concentration increased thermal runaway likelihood, while, counter‐intuitively, hot spot volume has no effect. An LDPE runaway map is provided to quantify the combinations that result in safe reactor operation. This allows manufacturers to make more informed control actions and to determine safe reactor conditions based on local mixture composition and temperature alone. [ABSTRACT FROM AUTHOR]

Despite a substantial impact on various economic and cell technology factors, the influence of electrolyte quantities is rarely addressed in research. This study examines the impact of varying electrolyte quantities on cell performance and aging processes using three different electrolytes: LP57 (1 M LiPF6 in ethylene carbonate:ethyl methyl carbonate (EC:EMC 3:7 w/w), LP572 (LP57+2 wt.% vinylene carbonate (VC)) and LP57 + absVC (18.351 mg VC). Comprehensive analytical post mortem investigations revealed that continuous excessive electrolyte decomposition determines the performance of cells using LP57, leading to enhanced irreversible lithium‐ion loss and interphase thickening with increasing electrolyte volume. Impedance rise due to the growth of the interphase was also identified as the cause of degrading cell performance with rising amounts of LP572, attributed to an increasingly pronounced consumption of VC rather than electrolyte aging effects. By varying the electrolyte quantity while maintaining a constant amount VC within the cell system, the differences in cell performance were minimized, and observed deteriorating effects were suppressed. This study demonstrates the sensitive interdependence of electrolyte volume and additive concentration, practically affecting aging behavior. Comprehensively understanding the characteristics of each individual electrolyte component and tailoring the electrolytes to cell‐specific cell properties proves to be crucial to optimize cell performance. [ABSTRACT FROM AUTHOR]

Ethylene dimerization is an industrial process that is currently carried out using homogeneous catalysts. Here we present a highly active heterogeneous catalyst containing minute amounts of atomically dispersed Pd. It requires no co‐catalyst(s) or activator(s) and significantly outperforms previously reported catalysts tested under similar reaction conditions. The selectivity to C4‐ and C6‐hydrocarbons was about 80 % and 10 % at 42 % ethylene conversion at 200 °C using an industrially relevant feed containing 50 vol % ethylene, respectively. Our kinetic and catalyst characterization experiments complemented by density functional theory calculations provide molecular insights into the local environment of isolated Pd(II)Ox species and their role in achieving high activity in the target reaction. When the developed catalyst was rationally integrated with a Mo‐containing olefin metathesis catalyst in the same reactor, the formed butenes reacted with ethylene to propylene with a selectivity of 98 % at about 24 % ethylene conversion. [ABSTRACT FROM AUTHOR]

SUMMARY: Long non‐coding RNAs (lncRNAs) play crucial roles in various biological processes in plants. However, the functional mechanism of lncRNAs in fruit ripening, particularly the transition from unripe to ripe stages, remains elusive. One such lncRNA1840, reported by our group, was found to have important role in tomato fruit ripening. In the present study, we gain insight into its functional role in fruit ripening. CRISPR‐Cas9 mediated lncRNA1840 mutants caused the delayed tomato fruit ripening. Notably, loss function of lncRNA1840 did not directly impact ethylene signaling but rather delay ethylene synthesis. Transcriptomic analysis revealed differences in the expression of ripening related genes in lncRNA1840 mutants, suggesting that it is involved in gene regulation of fruit ripening. We used Chromatin Isolation by RNA Purification (ChIRP)‐Seq to identify lncRNA1840 binding sites on chromatin. ChIRP‐seq suggested that lncRNA1840 had occupancy on 40 genes, but none of them is differentially expressed genes in transcriptomic analysis, which indicated lncRNA1840 might indirectly modulate the gene expression. ChIRP‐mass spectrometry analysis identified potential protein interactors of lncRNA1840, Pre‐mRNA processing splicing factor 8, highlighting its involvement in post‐transcriptional regulatory pathways. In summary, lncRNA1840 is key player in tomato plant growth and fruit ripening, with multifaceted roles in gene expression and regulatory networks. Significance Statement: Long non‐coding RNAs (lncRNAs) play important roles in various biological processes in plants, but the mechanism of action of lncRNAs during fruit ripening remains unexplored. lncRNA1840 was identified in tomato, which confirmed that it affected the ripening process of tomato fruit and achieved post‐transcriptional regulation by participating in alternative splicing, which improved the regulatory network of tomato fruit ripening and filled the gap of lncRNA in the field of fruit ripening. [ABSTRACT FROM AUTHOR]

α‐Olefins are very important bulk and fine chemicals and their synthesis from ethylene, an abundantly available and inexpensive feedstock, is highly attractive. Unfortunately, the direct or on‐purpose synthesis of olefins from ethylene is limited to three examples, 1‐butene, 1‐hexene, and 1‐octene, all having a linear structure. Herein, the direct synthesis of 3‐methylenepentane and 4‐ethylhex‐1‐ene, branched trimerization, and tetramerization products of ethylene, respectively, is reported. Different molecular titanium catalysts, all highly active, with a selectivity toward the formation of the branched ethylene trimer or tetramer, the employment of different activators, and different reaction conditions are the key to selective product formation. The long‐time stability of selected catalysts employed permits upscaling as demonstrated for the synthesis of 4‐ethylhex‐1‐ene (52 g isolated, TON(ethylene) 10.7 · 106). [ABSTRACT FROM AUTHOR]

Plants synchronize their growth and development with environmental changes, which is critical for their survival. Among their life cycle transitions, seed germination is key for ensuring the survival and optimal growth of the next generation. However, even under favorable conditions, often germination can be blocked by seed dormancy, a regulatory multilayered checkpoint integrating internal and external signals. Intricate genetic and epigenetic mechanisms underlie seed dormancy establishment, maintenance, and release. In this review, we focus on recent advances that shed light on the complex mechanisms associated with physiological dormancy, prevalent in seed plants, with Arabidopsis thaliana serving as a model. Here, we summarize the role of multiple epigenetic regulators, but with a focus on histone modifications such as acetylation and methylation, that finely tune dormancy responses and influence dormancy-associated gene expression. Understanding these mechanisms can lead to a better understanding of seed biology in general, as well as resulting in the identification of possible targets for breeding climate-resilient plants. [ABSTRACT FROM AUTHOR]

Optoelectronic properties of linear π‐conjugated polymers/oligomers are of great importance for the fabrication of organic photonic and electronic devices. To this end, the π‐conjugated polymers/oligomers need to meet both optoelectronic and key structural properties in order to fulfill their implementation as active components. In particular, they need to possess low bandgap and high thermal, conformational, and photochemical stabilities. So far, several strategies have been developed to attain such requirements including the covalent and non‐covalent rigidification concepts of the π‐conjugated systems. On the basis of these findings, we describe herein the theoretical studies of novel series of covalently bridged derivatives demonstrating the benefits of the strategy. Comparison of these derivatives with compounds previously described in the literature highlights enhanced optoelectronic properties and behaviors that would be beneficial for the construction and development of new linear π‐conjugated polymers. [ABSTRACT FROM AUTHOR]

A bidentate ligand, 2,3‐dihydro‐2,2‐dimethyl‐7‐benzofuranol (ddbfOH), is used to synthesize the titanium complexes, ddbfOTi(OiPr)3(1) and (ddbfO)2Ti(OiPr)2(2). Combined with diethylaluminium chloride (Et2AlCl) and di‐n‐butylmagnesium (Bu2Mg), complexes 1 and 2 exhibit super high activity towards ethylene polymerization, and giving the ultra‐high molecular weight polyethylene (UHMWPE). After rationally optimizing the experimental conditions, the highest polymerization activity is achieved in both 1/ and 2/Et2AlCl/Bu2Mg catalytic systems (213.6×106 g‐PE⋅mol‐Ti−1 h−1, 142.8×106 g‐PE⋅mol‐Ti−1 h−1). The highest molecular weight (Mv =1905×104) can be achieved under a low polymerization temperature (−30 °C) at the expense of activity (3000 g‐PE⋅mol‐Ti−1 h−1). Additionally, through the investigation of various polymerization conditions on the activity and molecular weight of the catalytic system, we have found that the ratio of the catalyst and cocatalyst has a more significant impact on both activity and molecular weight. [ABSTRACT FROM AUTHOR]

ABSTRACT ETHYLENE RESPONSE FACTOR6 (ERF6) has emerged as a central player in stress‐induced plant growth inhibition. It orchestrates complex pathways that enable plants to acclimate and thrive in challenging environments. In response to various abiotic and biotic stresses, ERF6 is promptly activated through both ethylene‐dependent and ‐independent pathways, and contributes to enhanced stress tolerance mechanisms by activating a broad spectrum of genes at various developmental stages. Despite the crucial role of ERF6, there is currently a lack of published comprehensive insights into its function in plant growth and stress response. In this respect, based on the tight connection between ethylene and ERF6, we review the latest research findings on how ethylene regulates stress responses and the mechanisms involved. In addition, we summarize the trends and advances in ERF6‐mediated plant performance under optimal and stressful conditions. Finally, we also highlight key questions and suggest potential paths to unravel the ERF6 regulon in future research. [ABSTRACT FROM AUTHOR]

Ethephon (2-chloroethylphosphonic acid) is frequently used for flush management in order to maximize flowering in litchi. However, the optimal dosage of ethephon, which balances between flush control effect and the detrimental effect on leaves, is unknown. This study aimed to identify the optimal ethephon dosage and test more efficient ethephon application methods, using a drone for flush control and flowering promotion in litchi. The effects of a single manual full-tree spray of 250, 500 or 1000 mg/L of ethephon in early November on the bud break rate, leaf drop rate, net photosynthetic rate, LcFT1 expression and floral induction (panicle emergence rate and panicle number) in 'Jingganghongnuo' litchi were examined in the season of 2021–2022. In the season of 2022–2023, the effects of drone application of 1000 mg/L of ethephon in early November on bud growth and floral induction were observed. The results showed that the manual ethephon treatments were effective at enforcing bud dormancy and elongating the dormancy period and that the effects were positively dependent on dosage. One manual spray of 1000 mg/L of ethephon in late autumn enabled a dormancy period of 6 weeks. The treatments advanced seasonal abscission of old leaves in winter and caused short-term suppression on photosynthesis within 2 weeks after treatment. Ethephon treatments, especially at 1000 mg/L, enhanced the expression of LcFT1 in the mature leaves and promoted floral induction reflected by earlier panicle emergence and increased panicle emergence rate and number in the terminal shoot. The floral promotion effect was also positively dosage dependent. The cumulative chilling hours below 15 °C from the date of treatment to the occurrence of a 20% panicle emergence rate were lowered in ethephon treatments. A drone spray of 1000 mg/L of ethephon solution consumed a sixth of the manual spray solution volume and was two thirds less effective in suppressing bud break compared with manual spraying. However, it achieved a significant flowering promotion effect comparable to traditional manual spraying. The results suggest that ethephon application enhanced flowering responsiveness to chilling as well as enforced bud dormancy. The application of ethephon with a drone proved to be an efficient method for flush control and flower promotion. [ABSTRACT FROM AUTHOR]

The involvement of stress ethylene in early chilling injury (CI) symptom development of mature-green (MG) banana fruit was examined using the ethylene action inhibitor, 1-methyclopropene (1-MCP). MG banana fruit pretreated with 0 or 50 μg L−1 1-MCP were stored at two chilling temperatures, 5 °C or 10 °C, for 0, 1, 12, or 72 h (different CI stresses), then transferred to 20 °C (rewarming) for 2 d. Irreversible CI symptoms that developed during 72 h storage at 5 or 10 °C included vascular browning and epidermal color parameters (L*, chroma, and hue angle). Some CI symptoms drastically intensified during exposure to 5 or 10 °C for 72 h, even being exacerbated after rewarming. Fruit in the other treatments suffered milder CI, and the recovery response progressed from slight and reversible to severe and irreversible with longer durations of exposure to lower temperatures. The effect of 1-MCP pretreatment was to attenuate the effect of chilling in terms of the CI symptom development (i.e., the browning of sub-epidermal tissues and the increasing of electrolyte efflux) and to promote recovery after rewarming, especially for the fruit stored at 5 °C, indicating the potential involvement of ethylene in membrane structural alterations under CI stress. [ABSTRACT FROM AUTHOR]

Taraxacum kok-saghyz Rodin (TKS) is a recognized alternative source of natural rubber comparable to the rubber tree. The geranylgeranyl pyrophosphate synthase (GGPS) catalyzed the synthesis of geranylgeranyl pyrophosphate (GGPP), which is an important enzyme in the secondary metabolism pathway. In this study, we present the first analysis of the GGPS gene family in TKS, where a total of seven TkGGPS family members were identified. Their core motifs, conserved structural domains, gene structures, and cis-acting elements were described. In addition, two phylogenetic trees were constructed based on the Neighbor-Joining and Maximum-Likelihood methods, and the TkGGPSs were highly conserved and exhibited good collinearity with the other species. Transcriptome data showed that seven TkGGPS gene members were expressed in all the 12 tissues measured, and TkGGPS1, TkGGPS3, and TkGGPS6 were highly expressed in latex, suggesting that they may be associated with natural rubber synthesis. Meanwhile, quantitative real-time PCR (qRT-PCR) showed that the expression levels of the TkGGPS genes were regulated by the ethylene and methyl jasmonate (MeJA) pathways. Subcellular localization results indicated that all the TkGGPS proteins were also located in chloroplasts involved in photosynthesis in plants. This study will provide valuable insights into the selection of candidate genes for molecular breeding and natural rubber biosynthesis in TKS. [ABSTRACT FROM AUTHOR]

The present review is focused on current findings on the involvement of ethylene in seed biology. The responsiveness of seeds to ethylene depends on the species and the dormancy status, improving concentrations ranging from 0.1 to 200 μL L−1. The signaling pathway of ethylene starts with its binding to five membrane-anchored receptors, which results in the deactivation of Constitutive Triple Response 1 (CTR1, a protein kinase) that does not exert its inhibitory effect on Ethylene Insensitive 2 (EIN2) by phosphorylating its cytosolic C-terminal domain. An analysis of germination in the presence of inhibitors of ethylene synthesis or action, and using seeds from mutant lines altered in terms of the genes involved in ethylene synthesis (acs) and the signaling pathway (etr1, ein2, ein4, ctr1 and erf1), demonstrates the involvement of ethylene in the regulation of seed dormancy. The promoting effect of ethylene is also regulated through crosstalk with abscisic acid (ABA) and gibberellins (GAs), essential hormones involved in seed germination and dormancy, and Reactive Oxygen Species (ROS). Using a mutant of the proteolytic N-degron pathway, Proteolysis (PRT6), the Ethylene Response Factors (ERFs) from group VII (HRE1, HRE2, RAP 2.2, RAP2.3 and RAP 2.12) have also been identified as being involved in seed insensitivity to ethylene. This review highlights the key roles of EIN2 and EIN3 in the ethylene signaling pathway and in interactions with different hormones and discusses the responsiveness of seeds to ethylene, depending on the species and the dormancy status. [ABSTRACT FROM AUTHOR]

Petal senescence represents an extraordinary phase of flower development, involving precisely regulated biochemical and physiological reprogramming. Plant growth regulators (PGRs) stand as the chief regulatory switches to elicit such reprogramming causing programmed cell death (PCD) of petals. Ethylene is recognized as the key hormone that regulates senescence in ethylene-sensitive flowers. In contrast, there has been a constant pursuit to dispense the same role to a hormone other than ethylene in the ethylene-independent class of flowers. Pertinently, abscisic acid (ABA) is presumed to play a decisive role in the petal senescence of ethylene-insensitive flowers. Additionally, oxidative stress characterized by the accumulation of reactive oxygen species (ROS) is assumed to be the hallmark of PCD and senescence in petals. Consistent with this idea, the current investigation ascertains the role of PGRs viz., ethylene, ABA, and gibberellic acid (GA), besides ROS in regulating the senescence in ray florets of Calendula officinalis; a least documented ornamental of Asteraceae. The ray florets were analyzed for the transient biochemical changes from juvenility through maturity to senescence. Based on the current findings, it was ascertained that ABA plays a significant role in instigating senescence in ray florets of C. officinalis. Furthermore, postharvest treatment with ABA antagonists such as GA and sodium tungstate (ST) combatively delayed the senescence of this flower. GA and ST significantly reduced the hydrogen peroxide (H2O2) accretion and protein degradation, besides accentuating the cell membrane integrity and antioxidant system in the detached flowers of C. officinalis. [ABSTRACT FROM AUTHOR]

Fruit color is a key feature of fruit quality, primarily influenced by anthocyanin or carotenoid accumulation or chlorophyll degradation. Adapting the pigment content is crucial to improve the fruit's nutritional and commercial value. Genetic factors along with other environmental components (i.e., light, temperature, nutrition, etc.) regulate fruit coloration. The fruit coloration process is influenced by plant hormones, which also play a vital role in various physiological and biochemical metabolic processes. Additionally, phytohormones play a role in the regulation of a highly conserved transcription factor complex, called MBW (MYB-bHLH-WD40). The MBW complex, which consists of myeloblastosis (MYB), basic helix–loop–helix (bHLH), and WD40 repeat (WDR) proteins, coordinates the expression of downstream structural genes associated with anthocyanin formation. In fruit production, the application of plant hormones may be important for promoting coloration. However, concerns such as improper concentration or application time must be addressed. This article explores the molecular processes underlying pigment formation and how they are influenced by various plant hormones. The ABA, jasmonate, and brassinosteroid increase anthocyanin and carotenoid formation, but ethylene, auxin, cytokinin, and gibberellin have positive as well as negative effects on anthocyanin formation. This article establishes the necessary groundwork for future studies into the molecular mechanisms of plant hormones regulating fruit color, ultimately aiding in their effective and scientific application towards fruit coloration.Key message: In this article, we have discussed the underlying molecular mechanism of hormonal regulation of fruit color in fruit-bearing plant species. The process of regulating fruit color is influenced by plant hormones which have a significant role in the physiological and biochemical metabolic processes and the control of gene expression and MBW complex activity. [ABSTRACT FROM AUTHOR]

Leaf senescence and abscission in autumn are critical phenological events in deciduous woody perennials. After leaf fall, dormant buds remain on deciduous woody perennials, which then enter a winter dormancy phase. Thus, leaf fall is widely believed to be linked to the onset of dormancy. In Rosaceae fruit trees, DORMANCY-ASSOCIATED MADS-box (DAM) transcription factors control bud dormancy. However, apart from their regulatory effects on bud dormancy, the biological functions of DAMs have not been thoroughly characterized. In this study, we revealed a novel DAM function influencing leaf senescence and abscission in autumn. In Prunus mume, PmDAM6 expression was gradually up-regulated in leaves during autumn toward leaf fall. Our comparative transcriptome analysis using two RNA-seq datasets for the leaves of transgenic plants overexpressing PmDAM6 and peach (Prunus persica) DAM6 (PpeDAM6) indicated Prunus DAM6 may up-regulate the expression of genes involved in ethylene biosynthesis and signaling as well as leaf abscission. Significant increases in 1-aminocyclopropane-1-carboxylate accumulation and ethylene emission in DEX-treated 35S:PmDAM6-GR leaves reflect the inductive effect of PmDAM6 on ethylene biosynthesis. Additionally, ethephon treatments promoted autumn leaf senescence and abscission in apple and P. mume, mirroring the changes due to PmDAM6 overexpression. Collectively, these findings suggest that PmDAM6 may induce ethylene emission from leaves, thereby promoting leaf senescence and abscission. This study clarified the effects of Prunus DAM6 on autumn leaf fall, which is associated with bud dormancy onset. Accordingly, in Rosaceae, DAMs may play multiple important roles affecting whole plant growth during the tree dormancy induction phase. [ABSTRACT FROM AUTHOR]

The purpose of this study is the pyrolysis of the distilled fractions obtained in the coking process as such and hydrotreated with the aim of diversifying the feedstock used in pyrolysis. The application of hydrotreating followed by pyrolysis, determines the reduction of the aromatic and olefinic hydrocarbons content in the feedstock, which leads to the improvement of the distribution of the reaction products and the decrease in the level of coke deposits, compared to the pyrolysis of non-hydrotreated distillate fractions. This study also aims to calculate the kinetic parameters of the pyrolysis process for non-hydrotreated and hydrotreated coking fraction at three equivalent temperatures: T = 680 °C, T = 695 °C, T = 705 °C. [ABSTRACT FROM AUTHOR]

Fusicoccin (FC) is one of the most studied fungal metabolites to date. The finding that the plasma membrane H+-ATPase in combination with 14-3-3 proteins acts as a high-affinity receptor for FC was a breakthrough in the field. Ever since, the binding of FC to the ATPase–14-3-3 receptor complex has taken center stage in explaining all FC-induced physiological effects. However, a more critical review shows that this is not evident for a number of FC-induced effects. This review challenges the notion that all FC-affected processes start with the binding to and activation of the plasma membrane ATPase, and raises the question of whether other proteins with a key role in the respective processes are directly targeted by FC. A second unresolved question is whether FC may be another example of a fungal molecule turning out to be a 'copy' of an as yet unknown plant molecule. In view of the evidence, albeit not conclusive, that plants indeed produce 'FC-like ligands', it is worthwhile making a renewed attempt with modern improved technology to answer this question; the answer might upgrade FC or its structural analogue(s) to the classification of plant hormone. [ABSTRACT FROM AUTHOR]

The triple response phenotype is characteristic for seedlings treated with the phytohormone ethylene or its direct precursor 1-aminocyclopropane-carboxylic acid, and is often employed to find novel chemical tools to probe ethylene responses. We identified a benzoxazole-urea derivative (B2) partially mimicking ethylene effects in a triple response bioassay. A phenotypic analysis demonstrated that B2 and its closest analogue arinole (ARI) induced phenotypic responses reminiscent of seedlings with elevated levels of auxin, including impaired hook development and inhibition of seedling growth. Specifically, ARI reduced longitudinal cell elongation in roots, while promoting cell division. In contrast to other natural or synthetic auxins, ARI mostly acts as an inducer of adventitious root development, with only limited effects on lateral root development. Quantification of free auxins and auxin biosynthetic precursors as well as auxin-related gene expression demonstrated that ARI boosts global auxin levels. In addition, analyses of auxin reporter lines and mutants, together with pharmacological assays with auxin-related inhibitors, confirmed that ARI effects are facilitated by TRYPTOPHAN AMINOTRANSFERASE1 (TAA1)-mediated auxin synthesis. ARI treatment in an array of species, including Arabidopsis, pea, tomato, poplar, and lavender, resulted in adventitious root formation, which is a desirable trait in both agriculture and horticulture. [ABSTRACT FROM AUTHOR]

Using the structure-induced effect of KBH(mim)3 ligand, four 2-dimensional (2D) boron imidazolate frameworks with identical body framework and different dangling monocarboxylate ligands, have been synthesized. Electrocatalytic results indicate that the surrounding microenvironment regulation could effectively affect the activity and selectivity towards C2H4. BIF-151 showed the highest electrocatalytic performances with the Faraday efficiency (FE) of 25.94% for C2H4 at −1.4 V vs. RHE. [ABSTRACT FROM AUTHOR]

The synthesis and structural analysis of (Me3SiC5H4)TiCl2(OAr) [OAr = O-2,6-iPr2-4-RC6H2; R = H, SiEt3] revealed that it exhibits higher catalytic activities than (tBuC5H4)TiCl2(OAr), Cp*TiCl2(OAr), with efficient comonomer incorporation in ethylene/styrene copolymerization in the presence of a methylaluminoxane (MAO) cocatalyst. The catalytic activity in the copolymerization increased upon increasing the charged styrene concentration along with the increase in the styrene content in the copolymers, whereas the activities of other catalysts showed the opposite trend. (Me3SiC5H4)TiCl2(O-2,6-iPr2C6H3) displayed the most suitable catalyst performance in terms of its activity and styrene incorporation, affording amorphous copolymers with styrene contents higher than 50 mol% (up to 63.6 mol%) and with random styrene incorporation confirmed by 13C-NMR spectra. [ABSTRACT FROM AUTHOR]

Amorphous photocatalysts are characterized by numerous grain boundaries and abundant unsaturated sites, which enhance reaction efficiency from both kinetic and thermodynamic perspectives. However, amorphization strategies have rarely been used for photocatalytic CO2 reduction. Doping copper onto a metal–organic framework (MOF) surface can regulate the electronic structure of photocatalysts, promote electron transfer from the MOF to Cu, and improve the separation efficiency of electron‐hole pairs. In this study, an amorphous photocatalyst MOFw‐p/Cu containing highly dispersed Cu (0, I, II) sites was designed and synthesized by introducing a regulator and in situ copper species during the nucleation process of MOF (UiO‐66‐NH2). Various characterizations confirmed that the Cu species were anchored to the organometallic skeleton of the surface amorphization MOF structure. The synergistic effect of Cu doping and surface amorphization in MOFw‐p/Cu can significantly enhance the CO and CH4 yields while promoting the formation of the multicarbon product C2H4. The approach holds promise for developing novel, highly efficient MOFs as photocatalysts for CO2 photoreduction, enabling the production of high‐value‐added C2 products. [ABSTRACT FROM AUTHOR]

HMGR (3-hydroxy-3-methylglutaryl-CoA reductase) plays a crucial role as the first rate-limiting enzyme in the mevalonate (MVA) pathway, which is the upstream pathway of natural rubber biosynthesis. In this study, we carried out whole-genome identification of Taraxacum kok-saghyz (TKS), a novel rubber-producing alternative plant, and obtained six members of the TkHMGR genes. Bioinformatic analyses were performed including gene structure, protein properties, chromosomal localization, evolutionary relationships, and cis-acting element analyses. The results showed that HMGR genes were highly conserved during evolution with a complete HMG-CoA reductase conserved domain and were closely related to Asteraceae plants during the evolutionary process. The α-helix is the most prominent feature of the secondary structure of the TkHMGR proteins. Collinearity analyses demonstrated that a whole-genome duplication (WGD) event and tandem duplication event play a key role in the expansion of this family and TkHMGR1 and TkHMGR6 have more homologous gene between other species. Cis-acting element analysis revealed that the TkHMGR gene family had a higher number of MYB-related, light-responsive, hormone-responsive elements. In addition, we investigated the expression patterns of family members induced by ethylene (ETH) and methyl jasmonate (MeJA), and their expression levels at different stages of T. kok-saghyz root development. Finally, subcellular localization results showed that six TkHMGR members were all located in the endoplasmic reticulum. In conclusion, the results of our study lay a certain theoretical basis for the subsequent improvement of rubber yield, molecular breeding of rubber-producing plants, and genetic improvement of T. kok-saghyz. [ABSTRACT FROM AUTHOR]

The discovery and development of efficient technologies that enable the use of CO2 as a starting material for chemical synthesis (at scale) is probably one of the biggest scientific challenges of our time. But a key question is if the cure will not be worse than the disease? In this work, the economic feasibility of the electrochemical reduction of CO2 to ethylene is assessed and it is demonstrated that from a Capital expenditure and Operational expenditure point of view the electrochemical production of ethylene from CO2 is not feasible under the current market conditions. Even in the case that the renewable electricity price would be zero, the feasibility is hampered by the state-of-the-art catalyst performance (selectivity) and the cost of the electrochemical reactor. Turning the installation on and off, if this would be even practically possible, is not interesting because our study shows that because of the high Capital expenditure, the payback time of the process would become unacceptably high. Finally, because of the high electricity requirement, this Carbon Capture and Utilization process has a lower CO2 avoidance potential than the substitution of gray electricity by green electricity. This means that today the available green electricity would best be used to close coal and gas based power plants instead of powering the electrochemical conversion of CO2 to ethylene. [ABSTRACT FROM AUTHOR]

Hevea brasiliensis is an important cash crop with the product named natural rubber (NR) for markets. Ethylene (ET) is the most effective yield stimulant in NR production but the molecular mechanism remains incomplete. Here, latex properties analysis, transcriptome analysis, and metabolic profiling were performed to investigate the mechanism of NR yield increase in four consecutive tappings after ET stimulation. The results revealed that sucrose and inorganic phosphate content correlated positively with dry-rubber yield and were induced upon ET stimulation. Stimulation with ET also led to significant changes in gene expression and metabolite content. Genes involved in phytohormone biosynthesis and general signal transduction as well as 51 transcription factors potentially involved in the ET response were also identified. Additionally, KEGG annotation of differentially accumulated metabolites suggested that metabolites involved in secondary metabolites, amino-acid biosynthesis, ABC transporters, and galactose metabolism were accumulated in response to ET. Integrative analysis of the data collected by transcriptomics and metabolomics identified those differentially expressed genes and differentially accumulated metabolites are mainly involved in amino-acid biosynthesis and carbohydrate metabolism. Correlation analysis of genes and metabolites showed a strong correlation between amino-acid biosynthesis during ET stimulation. These findings provide new insights into the molecular mechanism underlying the ET-induced increase in rubber yield and further our understanding of the regulatory mechanism of ethylene signaling in rubber biosynthesis. [ABSTRACT FROM AUTHOR]

Amorphous photocatalysts are characterized by numerous grain boundaries and abundant unsaturated sites, which enhance reaction efficiency from both kinetic and thermodynamic perspectives. However, amorphization strategies have rarely been used for photocatalytic CO2 reduction. Doping copper onto a metal–organic framework (MOF) surface can regulate the electronic structure of photocatalysts, promote electron transfer from the MOF to Cu, and improve the separation efficiency of electron‐hole pairs. In this study, an amorphous photocatalyst MOFw‐p/Cu containing highly dispersed Cu (0, I, II) sites was designed and synthesized by introducing a regulator and in situ copper species during the nucleation process of MOF (UiO‐66‐NH2). Various characterizations confirmed that the Cu species were anchored to the organometallic skeleton of the surface amorphization MOF structure. The synergistic effect of Cu doping and surface amorphization in MOFw‐p/Cu can significantly enhance the CO and CH4 yields while promoting the formation of the multicarbon product C2H4. The approach holds promise for developing novel, highly efficient MOFs as photocatalysts for CO2 photoreduction, enabling the production of high‐value‐added C2 products. [ABSTRACT FROM AUTHOR]

Plant hormones, pivotal regulators of plant growth, development, and response to environmental cues, have recently emerged as central modulators of epigenetic processes governing gene expression and phenotypic plasticity. This review addresses the complex interplay between plant hormones and epigenetic mechanisms, highlighting the diverse methodologies that have been harnessed to decipher these intricate relationships. We present a comprehensive overview to understand how phytohormones orchestrate epigenetic modifications, shaping plant adaptation and survival strategies. Conversely, we explore how epigenetic regulators ensure hormonal balance and regulate the signalling pathways of key plant hormones. Furthermore, our investigation includes a search for novel genes that are regulated by plant hormones under the control of epigenetic processes. Our review offers a contemporary overview of the epigenetic–plant hormone crosstalk, emphasizing its significance in plant growth, development, and potential agronomical applications. [ABSTRACT FROM AUTHOR]

Isolated metal sites catalysts (IMSCs) play crucial role in electrochemical CO2 reduction, with potential industrial applications. However, tunable synthesis strategies for IMSCs are limited. Herein, we present an atomic printing strategy that draws inspiration from the ancient Chinese “movable‐type printing technology”. Selecting customizable combinations of metal atoms as metal precursors from an extensive binuclear metal library. A series of dual‐atom catalysts were prepared by utilizing the edge nitrogen atoms in the C2N cavity as anchoring “pincers” to capture metal atoms. To prove utility, the dual atom catalyst Cu2‐C2N is investigated as electrocatalytic CO2RR catalyst. The synergistic interaction of dual Cu atoms promotes C−C coupling and guarantees FEC2+ (90.8 %) and FEC2H4. (71.7 %) at −1.10 V vs RHE. DFT calculations revealed the Cu2 site would be subtly flipped during CO2RR for enhancing *CO adsorption and dimerization. We validate that atomic printing strategies are applicable to wide range of metal combinations, representing a significant advancement in the development of IMSCs. [ABSTRACT FROM AUTHOR]

A series of novel diphosphinoamine (PNP) ligands bearing a P-alkenyl group were synthesized and applied in chromium-catalyzed selective ethylene tri-/tetramerization by in situ combination of Cr(acac)3 and modified methylalumoxane (MMAO-3A). The ligand substitution and oligomerization conditions have a remarkable influence on the catalytic activity and controllable selectivity. Most of these PNP ligands are highly active for ethylene tri-/tetramerization with considerable selectivity. An asymmetric diisopropenylphosphanyl ligand with an N-cyclohexyl group achieved the highest activity of 2036 kg (g Cr h−1)−1 with a high total selectivity of 81.1 wt% toward valuable 1-hexene (43.0 wt%) and 1-octene (38.1 wt%) at 40 bar ethylene and 60 °C. An asymmetric mixed isopropenyl/ethylphosphanyl ligand with an N-isopropyl group exhibited a high 1-octene selectivity of 65.5 wt% and a high total 1-hexene/1-octene selectivity (91.5 wt%) with a high activity of 1256 kg (g Cr h−1)−1. [ABSTRACT FROM AUTHOR]

The chemical industry must reduce greenhouse gas emissions to align with the Paris Agreement. In this study, we assess the economic feasibility of electrochemical oxidations (i.e., using water and electricity to create reactive oxygen species) as an alternative to current energy- and emissions-intensive industrial methods for producing ethylene oxide (EO) and glycol (EG) and propylene oxide (PO) and glycol (PG). Technoeconomic analyses reveal ethylene electrooxidations in a gas diffusion electrode assembly reach economic viability at single-pass conversions above 70% for EO and 40% for EG with overall Faradaic efficiencies (FE) above 20% and high carbon selectivities toward the desired products. Propylene electrooxidation achieves economic feasibility at a minimum single-pass conversion of 10% and overall FE greater than 10% for both PO and PG, while allowing variance in carbon selectivity. These electrochemical methods require current densities of at least 0.1 A cm-2 and lifetimes greater than 2 years for industrial scalability. We demonstrate that electrochemical oxidations can reduce emissions and operational hazards in the production of key chemical intermediates through benchmarking targets for the experimental advancement of alkene electrooxidations. [ABSTRACT FROM AUTHOR]

Higher olefins (HO) are a category of unsaturated hydrocarbons widely used in industry applications to make products essential for daily human life. Establishing safe exposure limits requires a solid data matrix that facilitates understanding of their toxicological profile. This in turn allows for data to be read across to other members of the category, which are structurally similar and have predictable physico-chemical properties. Five independent subchronic oral toxicity studies were conducted in Wistar rats with Oct-1-ene, Nonene, branched, Octadec-1-ene, Octadecene and hydrocarbon C12-30, olefin-rich, ethylene polymn. by product, at doses ranging from 20 to 1000 mg/kg bw. These HO were selected considering gut absorption, carbon chain length, double-bond position and carbon backbone structural variations. Generally, limited and non-adverse toxicity effects were observed at the end of the treatment for short carbon chain HO. For instance, alpha 2u-globulin nephropathy in the male rats and liver hypertrophy. No clear trend in systemic toxicity was linked to the double-bond position. Key factors for hazard assessment include absorption, carbon chain length, and branching, with Nonene, branched, identified as the worst-case substance. Taken together, the no observed adverse effect level (NOAEL) of each HO in these subchronic studies was set at the highest dose tested. [ABSTRACT FROM AUTHOR]

The pursuit of high efficacy C−C coupling during the electrochemical CO2 reduction reaction remains a tremendous challenge owing to the high energy barrier of CO2 activation and insufficient coverage of the desired intermediates on catalytic sites. Inspired by the concept of capture‐coupled CO2 activation, we fabricated quinone‐grafted carbon nanofibers via an in situ oxidative carbonylation strategy. The quinone functionality of carbon nanofibers promotes the capture of CO2 followed by activation. At a current density of 400 mA cm−2, the Faradaic efficiency of ethylene reached 62.9 %, and a partial current density of 295 mA cm−2 was achieved on the quinone‐rich carbon nanofibers. The results of in situ spectroscopy and theoretical calculations indicated that the remarkable selectivity enhancement in ethylene originates from the quinone structure, rather than the electronic properties of Cu particles. The interaction of quinone with CO2 increases the local *CO coverage and simultaneously hinders the co‐adsorption of *H on Cu sites, which greatly reduces the energy barrier for C−C coupling and restrains subsequent *CO protonation. The modulation strategy involving specific oxygenated structure, as an independent degree of freedom, guides the design of functionalized carbon materials for tailoring the selectivity of desired products during the CO2 capture and reduction. [ABSTRACT FROM AUTHOR]

Copper (Cu)-based catalysts show promise for electrocatalytic CO2 reduction (CO2RR) to multi-carbon alcohols, but thermodynamic constraints lead to competitive hydrocarbon (e.g., ethylene) production. Achieving selective ethanol production with high Faradaic efficiency (FE) and current density is still challenging. Here we show a multivalent Cu-based catalyst, Cu-2,3,7,8-tetraaminophenazine-1,4,6,9-tetraone (Cu-TAPT) with Cu2+ and Cu+ atomic ratio of about 1:2 for CO2RR. Cu-TAPT exhibits an ethanol FE of 54.3 ± 3% at an industrial-scale current density of 429 mA cm−2, with the ethanol-to-ethylene ratio reaching 3.14:1. Experimental and theoretical calculations collectively unveil that the catalyst is stable during CO2RR, resulting from suitable coordination of the Cu2+ and Cu+ with the functional groups in TAPT. Additionally, mechanism studies show that the increased ethanol selectivity originates from synergy of multivalent Cu sites, which can promote asymmetric C–C coupling and adjust the adsorption strength of different carbonaceous intermediates, favoring hydroxy-containing C2 intermediate (*HCCHOH) formation and formation of ethanol. This study proposes a multivalent Cu-based catalyst (Cu-TAPT) for electrocatalytic CO2RR, which promotes specific intermediate formation by the synergy of Cu2+ and Cu+ sites, thereby achieving a 54.3% Faradaic efficiency of ethanol at 429 mA cm−2. [ABSTRACT FROM AUTHOR]

To better understand the relationship between MdMCs and ethylene during apple fruit ripening. "Golden Delicious" apple fruit were treated with ethephon (0.2 mmol L−1) and ethylene action inhibitor 1-methylcyclopropene (1-MCP) (1 µL L−1) after harvest, and the ethylene-responsive transcription factor MdERF2 was transiently over-expressed in apple fruit at commercial maturity. Our results showed that climacteric peaks of respiration rate and ethylene production were advanced by ethephon treatment while delayed by application of 1-MCP. Ethephon treatment increased activity of MC, content of malondialdehyde (MDA), and relative electrical conductivity (REC) compared with controls during ripening, while 1-MCP treatment had the opposite effects. Expression of MdMC04, MdMC07, MdMC12, MdMC14, MdMC16, MdMC18, MdMC19, and MdMC20 was differentially induced by ethephon treatment, while their expression was generally downregulated by application of 1-MCP compared with controls during ripening. MdMC06 expression was induced at the late ripening stage by 1-MCP treatment but reduced by ethephon application during ripening compared to the control group. Transcript levels of MdMC01 and MdMC13 were promoted by both 1-MCP and ethephon treatments during ripening. In contrast, expression of MdMC17, MdMC05, MdMC02, MdMC21, MdMC10, and MdMC09 was differentially reduced after application of ethephon and 1-MCP during ripening compared with controls. Expression patterns of MdMCs varied in fruit transiently over-expressing MdERF2 during ripening. These results indicated that MdMCs expression was modulated by ethylene signal during apple ripening. Our findings would be useful for further unraveling the molecular mechanism of ethylene signaling in modulating MC genes during apple ripening. [ABSTRACT FROM AUTHOR]

This paper discusses the mechanisms by which fungi manipulate plant physiology and suppress plant defense responses by producing effectors that can target various host proteins. Effector-triggered immunity and effector-triggered susceptibility are pivotal elements in the complex molecular dialogue underlying plant–pathogen interactions. Pathogen-produced effector molecules possess the ability to mimic pathogen-associated molecular patterns or hinder the binding of pattern recognition receptors. Effectors can directly target nucleotide-binding domain, leucine-rich repeat receptors, or manipulate downstream signaling components to suppress plant defense. Interactions between these effectors and receptor-like kinases in host plants are critical in this process. Biotrophic fungi adeptly exploit the signaling networks of key plant hormones, including salicylic acid, jasmonic acid, abscisic acid, and ethylene, to establish a compatible interaction with their plant hosts. Overall, the paper highlights the importance of understanding the complex interplay between plant defense mechanisms and fungal effectors to develop effective strategies for plant disease management. [ABSTRACT FROM AUTHOR]

(1R,3R,5S,Z)-2-ethylidene-6,6-dimethyl-3-vinylbicyclo[3.1.1]heptane was prepared by hydrovinylation of nopadiene catalyzed by a cationic Ru complex. The structure was fully characterized by 1H- and 13C-NMR spectroscopy, including 2D-COSY and 2D-NOESY spectra, optical rotation, and combustion analysis. In contrast to the previously reported 1,2-hydrovinylation of 1-vinylcycloalkenes by this catalyst, the reaction with nopadiene proceeds by 1,4-addition of ethylene. [ABSTRACT FROM AUTHOR]

Investigating the effects of different segment compositions in block copolymers on their performance is crucial for enhancing material properties and developing new applications. In this study, we investigate the impact of differing segment compositions on the crystallization behavior, microphase separation characteristics, and physical properties of Poly(vinylcyclohexane)-b-poly(ethylene)-b-poly(vinylcyclohexane) (PVCH-PE-PVCH) block copolymers. In PVCH-PE-PVCH block copolymers, the longer PE segments significantly enhance crystallization capability and order. These long PE segments not only facilitate more effective microphase separation, promoting the formation of larger structural domains, but also favor the crystallization of the PE phase, thereby markedly improving the material's mechanical and optical properties. This reveals the pivotal role of the synergistic effect between long-chain PE distribution and microphase separation in regulating the structure and performance of high-performance polymer materials. Although theoretically, high PE content and high molecular weight are conducive to performance enhancement, this was not fully realized under conditions of weak phase separation capability and shorter PE chains. Therefore, we emphasize that optimizing the performance of these high-performance block copolymers through precise molecular design is feasible, providing powerful strategies and theoretical support for designing novel materials with specific functionalities. [ABSTRACT FROM AUTHOR]

Key message: Presented here are model Yang cycle, ethylene biosynthesis and signaling pathways in Cannabis sativa. C. sativa floral transcriptomes were used to predict putative ethylene-related genes involved in sexual plasticity in the species. Sexual plasticity is a phenomenon, wherein organisms possess the ability to alter their phenotypic sex in response to environmental and physiological stimuli, without modifying their sex chromosomes. Cannabis sativa L., a medically valuable plant species, exhibits sexual plasticity when subjected to specific chemicals that influence ethylene biosynthesis and signaling. Nevertheless, the precise contribution of ethylene-related genes (ERGs) to sexual plasticity in cannabis remains unexplored. The current study employed Arabidopsis thaliana L. as a model organism to conduct gene orthology analysis and reconstruct the Yang Cycle, ethylene biosynthesis, and ethylene signaling pathways in C. sativa. Additionally, two transcriptomic datasets comprising male, female, and chemically induced male flowers were examined to identify expression patterns in ERGs associated with sexual determination and sexual plasticity. These ERGs involved in sexual plasticity were categorized into two distinct expression patterns: floral organ concordant (FOC) and unique (uERG). Furthermore, a third expression pattern, termed karyotype concordant (KC) expression, was proposed, which plays a role in sex determination. The study revealed that CsERGs associated with sexual plasticity are dispersed throughout the genome and are not limited to the sex chromosomes, indicating a widespread regulation of sexual plasticity in C. sativa. [ABSTRACT FROM AUTHOR]

Hierarchical ZSM‐5 zeolite materials with different SiO2/Al2O3 molar ratios in the range of 60–300 were synthesized using soft templating and microemulsion methods to generate zeolite materials with narrow mesopore size distributions. The resulting materials were characterized by X‐ray flourescence (XRF), Fourier transform infra‐red (FTIR) spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy (SEM), ammonia temperature programmed desorption (NH3‐TPD), thermo‐gravimetric analysis (TGA), Brunauer‐Emmett‐Teller (BET) surface area measurements, and products from the catalytic tests were analyzed by gas chromatography (GC). The XRF analysis determined that the Si/Al ratios for the synthesized ZSM‐5 were close to the batch ratios. The XRD and FTIR results revealed that the synthesized samples had crystalline ZSM‐5 zeolite structures. The small angle observed from the XRD patterns confirmed the presence of mesopores in the structure of the prepared materials. The SEM results showed that the ZSM‐5 synthesized materials had different morphologies and particle sizes, as well as worm‐like holes indicating that some macropores with average pore sizes ranging between 68 and 85 nm were successfully generated in these materials. NH3‐TPD results showed that the total acidity of the prepared materials decreased with an increase in the Si/Al (SA) ratio following this trend: SA = 71 > 177 > 345. This may be due to the decrease in the aluminum content, which is largely responsible for the formation of acidic sites in zeolites. The acid strength was found to increase with a decrease in the Si/Al ratio, highlighted by the peak shifts to higher temperatures. From the BET results, the SA = 71 was observed to have the highest SSA of 618 m2/g given by its micropore area of 103 m2/g and an external surface area of 515 m2/g. The high external surface area present in the material was due to the development of mesopores with narrow pore size distribution of approximately 6 nm indicating the success of the microemulsion method for the generation of hierarchical zeolites with well controlled pore sizes. The hierarchical ZSM‐5 catalysts were tested for the cracking of various hydrocarbon chain lengths. Low conversions, less than 10%, were obtained in the cracking of hexane; however, when cracking longer chain C12 hydrocarbons, the conversion increased remarkably to 100%. The catalyst with SA = 71 had the highest selectivity towards ethylene and propylene olefins due to its higher acidity in comparison with the other prepared catalysts. Improved activity, selectivity towards ethylene and propylene greater than 60%, and enhanced catalyst stability were demonstrated when using a hierarchical ZSM‐5 compared to the commercial catalyst in the cracking of dodecane. High selectivity towards light olefins was obtained for the cracking of waste tire‐derived oil. The results suggest that these hierarchical materials are suited to the cracking of long chain hydrocarbons and are promising materials for the valorization of waste tire‐derived oils. [ABSTRACT FROM AUTHOR]

Key message: Auxin (AUX) promotion of apple fruit ripening is ethylene-dependent, and AUX-MdARF17-MdERF003 plays a role in AUX-promoted ethylene synthesis in apple. Phytohormones play important roles in plant growth and fleshy fruit ripening, and the phytohormone auxin (AUX) can either promote or inhibit the ripening of fleshy fruits. Although AUX can influence ethylene (ETH) synthesis in apple (Malus domestica) fruits by affecting ETH system II, this mechanism remains to be explored. Here, we identified an ETH response factor (ERF) family transcription factor, MdERF003, whose expression could be activated by naphthalene acetic acid. The transient silencing of MdERF003 inhibited ETH synthesis in fruits, and MdERF003 could bind to the MdACS1 promoter. To explore the upstream target genes of MdERF003, we screened the MdARF family members by yeast one-hybrid assays of the MdERF003 promoter, and found that the transcription factor MdARF17, which showed AUX-promoted expression, could bind to the MdERF003 promoter and promote its expression. Finally, we silenced MdERF003 in apple fruits overexpressing MdARF17 and found that MdERF003 plays a role in MdARF17-promoted ETH synthesis in apple. Thus, AUX–MdARF17–MdERF003 promotes ETH synthesis in apple fruits. [ABSTRACT FROM AUTHOR]