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In this article, we present evidence of a distinct class of extreme events that occur during the transient chaotic state within network modeling using the Brusselator with a mutually coupled star network. We analyze the phenomenon of transient extreme events in the network by focusing on the lifetimes of chaotic states. These events are identified through the finite-time Lyapunov exponent and quantified using threshold and statistical methods, including the probability distribution function (PDF), generalized extreme value (GEV) distribution, and return period plots. We also evaluate the transitions of these extreme events by examining the average synchronization error and the system's energy function. Our findings, validated across networks of various sizes, demonstrate consistent patterns and behaviors, contributing to a deeper understanding of transient extreme events in complex networks. [ABSTRACT FROM AUTHOR]

A novel dicoumarol-based copolyester was synthesized via a one-step polycondensation reaction using titanium tetraisopropoxide (TTIP) as a catalyst. The copolyester was characterized using Fourier transform infrared spectroscopy (FT-IR), Nuclear Magnetic Resonance (NMR) spectroscopy (1H and 13C), and Differential Scanning Calorimetry (DSC). Scanning electron microscopy (SEM) was used to examine the surface morphology before and after degradation. The synthesized copolyester exhibited toxicity against MCF-7 breast cancer cells, with an IC50 value of 62.5 μg/mL, and demonstrated potential as a drug carrier with a consistent drug-release rate. The combination of dicoumarol, itaconic acid, and 1,12-dodecanediol in the copolyester enhances its biomedical capabilities, with dicoumarol providing anticancer properties, itaconic acid offering biocompatibility and mechanical stability, and 1,12-dodecanediol ensuring structural integrity and responsiveness. This study presents the first example of a dicoumarol-substituted copolyester, which was thoroughly characterized and shown to have promising biocompatibility for targeted anticancer therapy. The synthesis of this novel copolyester from renewable sources highlights the growing interest in sustainable materials for pharmaceutical and biomedical applications, particularly in drug delivery and tissue engineering for cancer treatment.

This study dealt with preparation and efficient utilization of may flower seed carbon (MFSC) to adsorb Fe (II) from aqueous solution. Batch experiments were conducted to analyze the impact of adsorption parameters viz, contact time, initial metal ion concentration, adsorbent dose and pH on adsorption process. The results revealed that iron removal increased gradually up to a maximum of 99.52% and removal attains maximum at 80 min. Complete removal of Fe (II) was observed at a dosage of 100 mg/50 mL of pH 6 and 80 min contact time. Experimental data were fitted with Langmuir, Freundlich and Dubinin –Radushkevich (D‐R) isotherm models and was observed to be better explained by Langmuir adsorption model. The monolayer adsorption was 49.75 mg g−1 of Fe (II) on MFSC and the adsorption process followed Pseudo second order kinetics; regeneration of carbon was possible with 0.3 M HCl. © 2018 American Institute of Chemical Engineers Environ Prog, 38: S243–S249, 2019 [ABSTRACT FROM AUTHOR]

Abundant availability of lignocellulosic biomass (LCB) coupled with diverse pretreatment methods have made it a promising option for energy production. However, it faces several challenges, some of which can be overcome by integrating pretreatment processes. The present study aims to optimize the integration of two different pretreatment methods—torrefaction (to reduce moisture content and fractionate biomass) and alkaline pretreatment of wood waste (to delignify biomass)—and utilize it for bioethanol production. Pretreatment performance was evaluated based on delignification, biomass hydrolysis, and bioethanol production. Initially, torrefaction was performed in a continuous reactor at a temperature range of 225–300 °C, followed by optimization of the critical parameters of alkaline pretreatment of torrefied wood waste (TWW), that is, the temperature, reaction time, solid–liquid ratio, and alkali concentration. Subsequently, the chemical and carbohydrate compositions of raw wood waste (RWW) and TWW were studied, followed by enzymatic hydrolysis and bioethanol fermentation. Integrated pretreatment positively impacted the cellulose and glucose contents of raw and torrefied biomass at lower temperatures. The enzymatic hydrolysis of TWW treated with alkali produced higher levels of glucose and bioethanol than (stand-alone) TWW. These results can be used as a basis for choosing the most suitable pretreatment for enhanced biomass conversion.

To face the impact of climate change in all dimensions of our society in the near future, the European Union (EU) has established an ambitious target. Until 2050, the share of renewable power shall increase up to 75% of all power injected into nowadays’ power grids. While being clean and having become significantly cheaper, renewable energy sources (RES) still present an important disadvantage compared to conventional sources. They show strong fluctuations, which introduce significant uncertainties when predicting the global power outcome and confound the causes and mechanisms underlying the phenomena in the grid, such as blackouts, extreme events, and amplitude death. To properly understand the nature of these fluctuations and model them is one of the key challenges in future energy research worldwide. This review collects some of the most important and recent approaches to model and assess the behavior of power grids driven by renewable energy sources. The goal of this survey is to draw a map to facilitate the different stakeholders and power grid researchers to navigate through some of the most recent advances in this field. We present some of the main research questions underlying power grid functioning and monitoring, as well as the main modeling approaches. These models can be classified as AI- or mathematically inspired models and include dynamical systems, Bayesian inference, stochastic differential equations, machine learning methods, deep learning, reinforcement learning, and reservoir computing. The content is aimed at the broad audience potentially interested in this topic, including academic researchers, engineers, public policy, and decision-makers. Additionally, we also provide an overview of the main repositories and open sources of power grid data and related data sets, including wind speed measurements and other geophysical data.

Bio-insecticidal research has focused on long-term vector control using essential oils (EOs). This study examined the larvicidal, oviposition-deterrent, and repellent properties of five medicinal herb-based EO formulations (EOFs) on mosquitoes that are vectors of dengue, filariasis, and malaria. EOFs were significantly more toxic to the larvae and pupae of Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti with LC50 = 9.23, 12.85, and 14.46 ppm, as well with 10.22, 11.39, and 12.81 ppm, with oviposition active indexes of −0.84, −0.95, and −0.92, respectively. Oviposition-deterrent repellence was found in 91.39%, 94.83%, and 96.09%. EOs and N, N-Diethyl-3-methylbenzamide (DEET) were prepared at various concentrations for time duration repellent bioassays (6.25–100 ppm). Ae. aegypti, An. stephensi, and Cx. quinquefasciatus were monitored for 300, 270, and 180 min, respectively. At 100 ppm, EOs and DEET had comparable repellence in terms of test durations. EOF’s primary components d-limonene (12.9%), 2,6-octadienal, 3,7-dimethyl, (Z) (12.2%), acetic acid, phenylmethyl ester (19.6%), verbenol (7.6%), and benzyl benzoate (17.4%) may be combined to make a mosquito larvicidal and repellant equivalent to synthetic repellent lotions. In the molecular dynamics simulations, limonene (−6.1 kcal/mol) and benzyl benzoate (−7.5 kcal/mol) had a positive chemical association with DEET (−6.3 kcal/mol) and interacted with the OBP binding pocket with high affinity and stability. This research will help local herbal product manufacturers and the cosmetics industry in developing 100% herbal insect repellent products to combat mosquito-borne diseases, including dengue, malaria, and filariasis.

Sustainable biofuel production is necessary to meet the daunting challenge of “fueling” growing economies with a significantly reduced carbon footprint. Although its higher oxygen content often hinders the direct conversion of lignocellulosic biomass (LCB) into energy-dense biofuels, microbial biofuel production from LCB still has potential. The production of primary alcohols by acetone–butanol–ethanol (ABE) fermentation has been practiced for more than a century to attain near-theoretical maximum. However, ABE produced conventionally by native microorganisms is not equivalent to fossil fuel-based aviation fuels in terms of energy density, volatility, and cost-efficiency. Various strategies have been adapted for the microbial synthesis of advanced fuels from renewable feedstock with the advancements in genetic engineering. Yet, the presence of inhibitors and the inefficiency of microbes to utilize or transport the sugar mixtures from LCB often impede titer and yield. However, ABE mixtures can act as platform chemicals to synthesize high-value biofuels by biocatalytic or chemo-catalytic applications. Chemical catalysts, in particular, are used to produce higher alcohols ranging from 3-carbon to 20-carbon fuels from the ABE fermentation mixture. This article reviews the recent trends in the production of higher biofuels from ABE mixtures using biological and chemical catalysts. Focus is placed on genomic and metabolic engineering strategies implemented to upgrade microbes for higher biofuel production via the fermentation of renewable feedstocks. This paper also summarizes the advancements in the chemical conversion route of an ABE fermentation mixture into higher biofuels. Finally, the review provides insights into future research toward commercializing renewable and sustainable higher biofuels and chemicals.

In this paper, we investigate sampled-data stabilization of memristor nonlinearity in Chua's circuits. The system stability pertaining to its switching nonlinearity covers two situations of flux thresholds. Through the stability analysis, the multistability characteristic is proved by its periodic invariant stable line. Moreover, the dynamical features of the considered system are examined in details by numerical and corresponding simulated experiments. Several statistical and analytical characteristic methods are used to confirm the existence of chaotic attractors. With the help of Lyapunov stability theory, new sufficient conditions are formulated using the linear matrix inequality (LMI) method to ensure robust stability and stabilization of closed-loop systems. Finally, we present a numerical example to ascertain the validity of the theoretical results obtained.

Abstract Background Sustainable biofuels, which are widely considered as an attractive alternative to fossil fuels, can be generated by utilizing various biomass from the environment. Marine biomass, such as red algal biomass, is regarded as one potential renewable substrate source for biofuels conversion due to its abundance of fermentable sugars (e.g., galactose). Previous studies focused on the enhancement of biofuels production from different Clostridium species; however, there has been limited investigation into their metabolic pathways, especially on the conversion of biofuels from galactose, via whole genomic comparison and evolutionary analysis. Results Two galactose-utilizing Clostridial strains were examined and identified as Clostridium acetobutylicum strain WA and C. beijerinckii strain WB. Via the genomic sequencing of both strains, the comparison of the whole genome together with the relevant protein prediction of 33 other Clostridium species was established to reveal a clear genome profile based upon various genomic features. Among them, five representative strains, including C. beijerinckii NCIMB14988, C. diolis DSM 15410, C. pasteurianum BC1, strain WA and WB, were further discussed to demonstrate the main differences among their respective metabolic pathways, especially in their carbohydrate metabolism. The metabolic pathways involved in the generation of biofuels and other potential products (e.g., riboflavin) were also reconstructed based on the utilization of marine biomass. Finally, a batch fermentation process was performed to verify the fermentative products from strains WA and WB using 60 g/L of galactose, which is the main hydrolysate from algal biomass. It was observed that strain WA and WB could produce up to 16.98 and 12.47 g/L of biobutanol, together with 21,560 and 10,140 mL/L biohydrogen, respectively. Conclusions The determination of the production of various biofuels by both strains WA and WB and their genomic comparisons with other typical Clostridium species on the analysis of various metabolic pathways was presented. Through the identification of their metabolic pathways, which are involved in the conversion of galactose into various potential products, such as biobutanol, the obtained results extend the current insight into the potential capability of utilizing marine red algal biomass and provide a systematic investigation into the relationship between this genus and the generation of sustainable bioenergy.

This study explored the therapeutic potential of gut microbiota metabolites in managing Gestational Diabetes Mellitus (GDM). Using network pharmacology, molecular docking, and dynamics simulations, we identified key targets and pathways involved in GDM. We screened 135 gut-derived metabolites, with 8 meeting drug-likeness and pharmacokinetic criteria. Analysis revealed significant overlap with GDM-related targets, including AKT1, IL6, TNF, and STAT3. Functional enrichment analysis highlighted the AGE-RAGE signaling and inflammatory pathways as crucial in GDM pathogenesis. Molecular docking and dynamics simulations showed strong binding affinities and stable interactions between two metabolites, luteolin and naringenin chalcone, and the target protein AKT1. These findings suggest that gut microbiota-derived metabolites, particularly luteolin and naringenin chalcone, may effectively modulate key pathways in GDM, offering promising avenues for novel treatment strategies., 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 © 2025 Elsevier Ltd. All rights reserved.)

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Figure 5 of this article contains three images which have been duplicated within the figure. One of these duplications has additionally been flipped and reflected. The editors also have serious concerns about the integrity of the FTIR trace in Fig. 2(d) of the article. The corresponding author was contacted for comment about these concerns but was unable to provide a suitable explanation. The Editors have therefore lost confidence in the reliability of the findings presented in this article as a whole. Furthermore, an unauthorised authorship change was made to this paper at Revision 1, with author Ashraf Elfasakhany being added to the paper. No explanation was given for this change, nor was it approved by the editor. This authorship change breaches the policies of the journal and as a result, the editors no longer have confidence in this paper and are retracting it. The journal apologises for not having identified the problematic authorship change during the review process and for any resulting inconvenience., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Embelin is one of the primary compounds present in the Embelia ribes fruit. Embelin has a broader pharmacological activity such as Anti-inflammatory, anti-bacterial, antioxidant, and many more. The ultimate aim of the study is to ensure the impact of reduced embelin in the management of Alzheimer's disease. Embelin was isolated and modified by the reduction method, and the Modified Embelin derivative (MED) 3-Undecylcyclohexa-2,5-diene-1,2,4,5-tetraol was analysed through FT-IR, NMR, and Mass Spectroscopic techniques. MED was docked against acetylcholinesterase (AChE) amyloid beta (Aβ) receptors PDB ID: 1EVE & 1B68, respectively. The docking scores remain similar to that of positive standards galantamine and Donepezil.