Search Results (86)

The complexity of the biochemistry and the variety of possible environments make the subject of the no-growth limits of bacteria a very tough challenge. This present work addresses the problem of applying to the microbial cultures the polymer science approach, which is widespread in food technology. This requires the definition of a “dynamic state diagram” that reports the expected trends of the glass transition of two virtual polymers, which mimic the crowded cytoplasmic polymers and the polymeric meshwork of the cell envelope, respectively, versus the water content. At any given temperature, the water content at the glass transition represents the lowest limit for the relevant molecular mobility. This representation leads one to recognize that the lowest temperature to observe microbial growth coincides with that of the largest freeze-concentrated liquid phase, in line with the values predicted by the Ratkowsky empirical equation. In view of potential applications in predictive microbiology, this paper suggests an alternative interpretation for the highest tolerated temperature and the temperature of the largest specific growth rate. Full article

Rat hepatitis E virus (rat HEV) is an emerging zoonotic virus detected in rodents worldwide, with increasing evidence of presence in environmental sources such as surface water, wastewater and bivalves. This systematic review compiles and analyzes all the published research on rat HEV contamination in these matrices, as well as its implications for human health. A comprehensive literature search was conducted using databases such as PubMed, Scopus, Web of Science, and Mendeley, including studies published up until 27 May 2025. Studies were included if they evaluated rat HEV in water- or food-related matrices using molecular detection. The risk of bias was not assessed. The certainty of evidence was not formally evaluated. Limitations include reliance on PCR methods without infectivity confirmation. Following PRISMA inclusion and exclusion criteria, eight eligible studies were analyzed. The results show high detection rates of rat HEV RNA in influent wastewater samples from several high-income European countries, namely Sweden, France, Italy, Spain and Portugal. Lower detection rates were found in effluent wastewater and surface waters in Sweden. In bivalve mollusks sampled in Brazil, rat HEV RNA was detected in 2.2% of samples. These findings show the widespread environmental presence of rat HEV, particularly in urban wastewater systems. While human infections by rat HEV have been documented, the true extent of rat HEV zoonotic potential remains unclear. Given the risks associated with this environmental rat HEV contamination, enhanced surveillance, standardized detection methods, and targeted monitoring programs in food production and water management systems are essential to mitigate potential public health threats. Establishing such programs will be crucial for understanding the impact of rat HEV on human health. Full article

(1) Background: Aquatic organisms are more sensitive to pollutants than terrestrial ones, making them ideal for ecotoxicology studies. Chironomids, a key bioindicator species, have been widely used in environmental pollution research. With the continuous deepening of research on water environmental pollution and the continuous development of molecular biology, it is therefore very important to understand the current research progress of the toxicology of chironomids. (2) Methods: This study used bibliometrics to analyze 1465 publications on chironomid toxicology from the Web of Science and PubMed databases, aiming to reveal research trends, hotspots, and future directions. The data analysis involved Microsoft Excel, VOS viewer, CiteSpace, and ChatGLM. (3) Results: Heavy metals, pesticides, and microplastics were the main pollutants studied, with Chironomus riparius being the most researched species. The analysis indicated a growing research trend since 1998, reflecting an increasing global concern over aquatic pollution. This study concludes that more molecular-level research is needed to uncover toxic mechanisms and improve environmental risk assessments. (4) Conclusions: This work will aid scientists and policymakers in developing better pollution control strategies and conservation efforts for aquatic ecosystems, ultimately contributing to environmental protection and public health. Full article

Biomimetic peptides represent a growing class of active ingredients in modern cosmeceuticals, designed to mimic the function of the naturally occurring peptides involved in skin homeostasis, repair, and regeneration. Among them, acetyl hexapeptide-8 (AH-8), often referred to as a “botox-like” peptide, has received considerable attention for its potential to dynamically reduce wrinkles through the modulation of neuromuscular activity. AH-8 is widely used in topical formulations intended for anti-aging effects, scar treatment, and skin rejuvenation. This review provides a comprehensive overview of the structure and proposed mechanisms of action of AH-8, with particular focus on its efficacy and skin penetration properties. Due to its hydrophilic nature and relatively large molecular size, AH-8 faces limited permeability through the lipophilic stratum corneum, making effective dermal delivery challenging. Formulation strategies such as oil-in-water (O/W) and multiple water-in-oil-in-water (W/O/W) emulsions have been explored to enhance its delivery, but the ability of AH-8 to reach neuromuscular junctions remains uncertain. Preclinical and clinical studies indicate that AH-8 may reduce wrinkle depth, improve skin elasticity, and enhance hydration. However, the precise biological mechanisms underlying these effects—particularly the peptide’s ability to inhibit muscle contraction when applied topically—remain incompletely understood. In some studies, AH-8 has also shown beneficial effects in scar remodeling and sebum regulation. Despite promising cosmetic outcomes, AH-8’s low skin penetration limits its bioavailability and therapeutic potential. This review emphasizes the need for further research on formulation science and delivery systems, which are essential for optimizing the effectiveness of peptide-based cosmeceuticals and validating their use as non-invasive alternatives to injectable treatments. Full article

In contemporary construction practices, polycarboxylate superplasticizers (PCEs) have gained extensive utilization in concrete formulation owing to their exceptional dispersive properties and superior water reduction capabilities. Nevertheless, these admixtures demonstrate pronounced susceptibility to clay contamination, a critical limitation that substantially constrains their practical implementation. To mitigate this detrimental effect, multiple technical strategies have been developed to suppress clay sensitivity, with predominant approaches focusing on molecular structure optimization and incorporation of supplementary admixtures. This review systematically investigates the competitive adsorption mechanisms operating at the cement–clay interface. Through rigorous analysis of molecular architecture characteristics and synergistic admixture combinations, we comprehensively review current methodologies for enhancing the clay resistance of PCE-based systems. Furthermore, this paper proposes prospective directions for synthesizing clay-tolerant PCE derivatives, emphasizing molecular design principles and advanced formulation protocols that may inform future research trajectories in construction materials science. Full article

Background/Objectives: The Self-Nanoemulsifying Drug Delivery System (SNEDDS) has been widely applied in oral drug delivery, particularly for poorly water-soluble compounds. The successful development of SNEDDS largely depends on the precise composition of its components. This narrative review provides an in-depth analysis of Quality by Design (QbD), Design of Experiment (DoE), and in silico approach applications in SNEDDS development. Methods: The review is based on publications from 2020 to 2025, sourced from reputable scientific databases (Pubmed, Science direct, Taylor and francis, and Scopus). Results: Quality by Design (QbD) is a systematic and scientific approach that enhances product quality while ensuring the robustness and reproducibility of SNEDDS, as outlined in the Quality Target Product Profile (QTPP). DoE was integrated into the QbD framework to systematically evaluate the effects of predefined factors, particularly Critical Material Attributes (CMAs) and Critical Process Parameters (CPP_S), on the desired responses (Critical Quality Attributes/CQA), ultimately leading to the identification of the optimal SNEDDS formulation. Various DoEs, including the mixture design, response surface methodology, and factorial design, have been widely applied to SNEDDS formulations. The experimental design facilitates the analysis of the relationship between CQA and CMA/CPP, enabling the identification of optimized formulations with enhanced biopharmaceutical, pharmacokinetic, and pharmacodynamic profiles. As an essential addition to this review, in silico approach emerges as a valuable tool in the development of SNEDDS, offering deep insights into self-assembly dynamics, molecular interactions, and emulsification behaviour. By integrating molecular simulations with machine learning, this approach enables rational and efficient optimization. Conclusions: The integration of QbD, DoE, and in silico approaches holds significant potential in the development of SNEDDS. These strategies enable a more efficient, rational, and predictive formulation process. Full article

It is difficult to obtain efficient flowability of reactive powder concrete (RPC) mix due to a low water/binder ratio. The improvement of material flowability could be achieved by using the latest generation polycarboxylate superplasticizers (SPs), as well as by changing the mixing procedure. This paper presents two different superplasticizers’ effect on a fresh mix and hardened reactive powder concrete properties. Results of systematic experimental studies (including physicochemical and spectroscopic tests) and molecular modelling suggest that superplasticizer chemical structure plays a key role in shaping the properties of the concrete mix. It has been demonstrated that SP containing more carboxylate salt groups -COO⁻ Me⁺ improves fluidity of the RPC mix and causes its better deaeration. In contrast, hardened concrete exhibits lower porosity and consequently greater strength. On the other hand, a change in ingredients mixing from a three-stage to a four-stage procedure increased the mix flowability and the RPC strength. The chemical structure of SP and the mixing procedure had no significant impact on cement hydration progress. Our results could be useful both from the point of view of the basic science of materials and the applied field of planning of cement composites in construction. Full article

In this review article the synthesis and solid state structure of squaramide/squarate based metal–organic frameworks (MOFs) are analyzed and discussed. In detail, a thorough search in the literature revealed the successful utilization of these two organic molecules as MOF building blocks capable of catalyzing (i) water splitting reactions, (ii) electrocatalytic oxygen evolution reactions, and (iii) Michael addition reactions. Additionally, some of the highlighted examples also utilized these two molecular synthons to compose MOFs exhibiting gas adsorbent properties, concretely for capturing propadiene and propylene. In each of the selected examples a theoretical study of the noncovalent interactions (NCIs) established between the squaramide/squarate-based MOF and the guest molecules trapped inside was carried out, providing additional information regarding the strength of the MOF–guest interactions, which certainly influence the catalytic/adsorbent capabilities of these materials. We believe that the examples collected herein will be useful for those scientists working in the fields of supramolecular chemistry, crystal engineering, catalysis, and materials science by providing a retrospective guide on the role of squaramide and squarate in the formation of MOFs. Full article

Radiolysis of water and aqueous solutions refers to the decomposition of water and its solutions under exposure to ionizing radiation, such as γ-rays, X-rays, accelerated particles, or fast neutrons. This exposure leads to the formation of highly reactive species, including free radicals like hydroxyl radicals (^●OH), hydrated electrons (e⁻_aq), and hydrogen atoms (H^●), as well as molecular products like molecular hydrogen (H₂) and hydrogen peroxide (H₂O₂). These species may further react with each other or with solutes in the solution. The yield and behavior of these radiolytic products depend on various factors, including pH, radiation type and energy, dose rate, and the presence of dissolved solutes such as oxygen or ferrous ions, as in the case of the ferrous sulfate (Fricke) dosimeter. Aqueous radiation chemistry has been pivotal for over a century, driving advancements in diverse fields, including nuclear science and technology—particularly in water-cooled reactors—radiobiology, bioradical chemistry, radiotherapy, food preservation, wastewater treatment, and the long-term management of nuclear waste. This field is also vital for understanding radiation effects in space. Full article

White clover (Trifolium repens L.) is cultivated worldwide as a forage crop, green manure, and turfgrass, valued for its adaptability and broad distribution. Although numerous studies have investigated the adverse effects of drought stress on white clover growth and yield, a comprehensive bibliometric review has been lacking. To address this gap, we analyzed relevant publications from the Web of Science Core Collection (1990–2024) using VOSviewer (1.6.19.0) and R (4.3.1) software. Our findings reveal a consistent annual increase in research outputs, indicating sustained scholarly efforts to enhance white clover’s drought tolerance. China, New Zealand, Australia, the United States, and France lead in publication volume and maintain active international collaborations. Keyword co-occurrence analysis underscores the importance of phenotypic, physiological, and molecular mechanisms linked to drought resistance, particularly regarding plant growth and yield. Emerging directions include further exploration of transgenic technologies and molecular pathways to bolster white clover’s resilience under water-limited conditions. Overall, these insights offer a theoretical foundation for future research and provide a valuable reference for advancing sustainable agricultural practices in arid and semi-arid environments. Full article

The polymerase chain reaction (PCR) is a molecular biology tool with diverse applications in the aquatic sciences. Classical PCR is a nonquantitative method that can be used to detect target DNA sequences that are characteristic of particular microbial taxa but cannot determine their concentrations in water samples. Various quantitative forms of PCR have been developed to remove this limitation. Of these, the two that currently are used most widely are real-time quantitative PCR (qPCR) and droplet digital PCR (ddPCR). Several outlines of the mathematical and statistical basis of these methods for estimating target sequence concentrations are available in the literature, but we are aware of no thorough and rigorous derivation of the theoretical underpinnings of either. The purpose of this review is to provide such derivations, and to identify and compare the main strengths and weaknesses of the two methods. We find that both estimation methods are sound, provided careful attention is paid to specific details that differ between the two. With qPCR, it is especially important to reduce any significant PCR inhibition by sample constituents and to properly fit the standard curve to heteroskedastic calibration data. With ddPCR, it is important to ensure that the value of the mean droplet volume used in calculating concentrations is correct for the particular combination of droplet generator and master mix used. The advantages of qPCR include lower instrument and per-sample costs, a shorter turnaround time for obtaining results, a higher upper limit of quantification, and a wider dynamic range. The advantages of ddPCR include freedom from dependence on a standard curve, an inherently lower sensitivity to PCR inhibitors, a lower limit of quantification, a simpler theoretical basis, and simpler data analysis. We suggest qPCR often will be preferable in laboratory studies where investigators have significant control over the range of target sequence concentrations in samples, concentrations are sufficiently high so proper calibration does not require standards with concentrations low enough to exhibit exaggerated variability in the threshold cycle, and no significant inhibition is present, or more generally, in studies where funding levels do not permit the higher cost of instrumentation and supplies required by ddPCR or where the shorter turnaround time for qPCR is essential. If sufficient funds are available, ddPCR often will be preferable when the ability to quantify low concentrations is important, especially if inhibitors are likely to be present at concentrations that are problematic for qPCR. Full article

Epoxy-terminated hyperbranched polymers (EHBPs) are a class of macromolecular polymers with a hyperbranched structure containing epoxy groups. They possess characteristics such as low viscosity, high functionality, and thermal stability, which endow them with broad application potential in materials science and chemical engineering. This study uses epoxidized soybean oil (ESO) as the raw material, which undergoes ring-opening reactions with glycerol and is esterified with 2,2-bis(hydroxymethyl)propionic acid (DMPA) to obtain epoxy soybean oil polyol (EGD) with a high hydroxyl value. Subsequently, four types of EHBPs are synthesized by incorporating epichlorohydrin (ECH) in mass ratios of 1:3, 1:4, 1:5, and 1:6 under strong alkaline conditions. The product structure is characterized using FT–IR and GPC. The degree of branching of EGD is calculated using ¹H NMR and ¹³C NMR spectroscopy. The epoxy value of EHBPs is tested using the hydrochloric acid–acetone method, and the water contact angle, adhesion properties, rheological properties, and thermal properties of the EHBPs are also evaluated. The results show that the degree of branching of EGD is 0.45. The epoxy values of the EHBPs are 0.73, 0.79, 0.82, and 0.89 mol/100g, respectively. As the epoxy value and molecular weight of the epoxy hyperbranched polymers (EHBPs) increase, the water contact angle and adhesion strength of the EHBPs rise progressively and the viscosity decreases. Additionally, the glass transition temperature increases with the increase in the epoxy value. These epoxy hyperbranched polymers with low viscosity and high adhesion strength offer a promising approach for modifying surface coatings or formulating adhesives. Full article

Prof. George Whitesides’ pioneering contributions to the field of self-assembled monolayers (SAMs) have profoundly influenced biointerface science and beyond. This review explores the development of SAMs as highly organized molecular structures, focusing on their role in advancing surface science, biointerface research, and biomedical applications. Prof. Whitesides’ systematic investigations into the effects of SAMs’ terminal group chemistries on protein adsorption and cell behavior culminated in formulating “Whitesides’ Rules”, which provide essential guidelines for designing bioinert surfaces. These principles have driven innovations in anti-fouling coatings for medical devices, diagnostics, and other biotechnological applications. We also discuss the critical role of interfacial water in SAM bioinertness, with studies demonstrating its function as a physical barrier preventing protein and cell adhesion. Furthermore, this review highlights how data science and machine learning have expanded the scope of SAM research, enabling predictive models for bioinert surface design. Remarkably, Whitesides’ Rules have proven applicable not only to SAMs but also to polymer-brush films, illustrating their broad relevance. Prof. Whitesides’ work provides a framework for interdisciplinary advancements in material science, bioengineering, and beyond. The enduring legacy of his contributions continues to inspire innovative approaches to addressing challenges in biomedicine and biotechnology. Full article

Polybenzoxazines (PBzs), a class of high-performance thermosetting polymers, have gained significant attention for their exceptional thermal stability, mechanical properties, and chemical resistance, making them ideal for aerospace, electronics, and biomedical applications. Recent advancements emphasize their antimicrobial potential, attributed to unique structural properties and the ability to incorporate bio-active functional groups. This review highlights the synthesis, antimicrobial mechanisms, and applications of PBzs and their bio-based derivatives, focusing on sustainable materials science. PBzs demonstrate antimicrobial efficacy through mechanisms such as hydrophobic surface interactions and reactive functional group formation, preventing microbial adhesion and biofilm development. The incorporation of functional groups like amines, quaternary ammonium salts, and phenolic moieties disrupts microbial processes, enhancing antimicrobial action. Modifications with metal nanoparticles, organic agents, or natural bio-actives further augment these properties. Notable bio-based benzoxazines include derivatives synthesized from renewable resources like curcumin, vanillin, and eugenol, which exhibit substantial antimicrobial activity and environmental friendliness. Hybrid PBzs, combining natural polymers like chitosan or cellulose, have shown improved antimicrobial properties and mechanical performance. For instance, chitosan-PBz composites significantly inhibit microbial growth, while cellulose blends enhance film-forming capabilities and thermal stability. PBz nanocomposites, incorporating materials like silver nanoparticles, present advanced applications in biomedical and marine industries. Examples include zirconia-reinforced composites for dental restoration and urushiol-based PBzs for eco-friendly antifouling solutions. The ability to customize PBz properties through molecular design, combined with their inherent advantages such as flame retardancy, low water absorption, and excellent mechanical strength, positions them as versatile materials for diverse industrial and medical applications. This comprehensive review underscores the transformative potential of PBzs in addressing global challenges in antimicrobial material science, offering sustainable and multifunctional solutions for advanced applications. Full article

The electrochemical interface (EI) is the determining factor in the yield and mechanism of sustainable energy storage and conversion systems due to its intrinsic functionality as a dynamic junction with the symmetry breaking of the molecular arrangement for complex reaction fields of mass transport and heterogeneous electron transfer. At the EI, the externally applied potential stimulus drives the formation of the electrical double layer (EDL) and governs the adsorption of interfacial adsorbate species in aqueous electrolyte solutions. Water and its aqueous electrolyte systems are integral and quintessential elements in the technological innovation of various fields such as environmental sciences, electrocatalysis, photocatalysis, and biochemistry. Although deciphering the structure and orientation of water molecules at the electrode–electrolyte interface in a quantitative analysis is of utmost importance, assessing chemical phenomena at the buried EI was rather challenging due to the intricacy of selecting interface-specific methodologies. Based on the non-centrosymmetry of the interfaces’ electronic properties, sum-frequency generation (SFG) spectroscopy has been manifested to be specifically well suited for probing the EI with detailed and comprehensive characteristics of adsorbates’ chemical structures and electrochemical events. In this review, we holistically engage in a methodical and scrupulous assessment of the fundamental EDL models and navigate towards the connection of the renowned Stark effect and potential dependence of SFG spectra at heterogeneous electrode–electrolyte interfaces. We dissect the development, advantages, and available geometrical configurations of in situ SFG spectroscopy in harnessing the EI. A broad spectrum of applications in unraveling the water orientations and rationalizing the convoluted mechanism of fuel-generated electrocatalytic reactions with particular encumbrances and potential resolutions is underscored by leveraging SFG spectroscopy. Full article