Yihan Zhen, Cuijuan Zhang, Jiashu Yuan et al.

Journal of Materials Chemistry A • 2021

Three AQ-based materials are designed by incorporating acetamide and tetraalkylammonium ionic groups. The solubility and stability are enhanced, and the NARFB with a two-electron transfer process shows high cycling performance.

Avinava Kundu, Simmi Gautam, Biswarup Chakraborty

Journal of Materials Chemistry A • 2025

The redox and aqueous speciation chemistry of chalcogenides present in the Fe 3 X 4 (X = Se, S, O) structure also controls the electrochemical evolution of the reactive phase for alkaline oxygen evolution reaction.

Maria Victoria Martinez, Rusbel Coneo Rodriguez, Claudia R Rivarola et al.

ECS Meeting Abstracts • 2019

The loading and mass transfer of electroactive species inside polymeric hydrogels is of interest in drug delivery, analytical chemistry and water remediation. The electrochemical properties of the species could be affected by the viscoelastic properties of the gel, local ionic force and pH, as well as interactions (e.g. hydrophobic) between the ions and the polymer chains. Usually, a thin film of the hydrogel is deposited on the electrode, loaded with electroactive species and electrochemically investigated. However, the mass transfer is controlled by finite diffusion and depends of an unknown, the thickness of the layer in the experimental conditions. On the other hand, we show here that a simple set-up, consisting of a disk electrode pressed on the soft hydrogel, allows performing electrochemistry of electroactve species (redox complexes, arsenite, nitrite) loaded inside the hydrogel matrix. The redox complexes are present as dilute solutions and the hydrogel dimensions fulfill the semi-infinite diffusion boundary conditions. Therefore, the data analysis can be performed using the theoretical framework developed for electrochemical measurements in liquid solutions. The physicochemical properties of the bulk hydrogels are evaluated by measuring the swelling kinetics, in the same conditions of the electrochemical measurements. Redox cations (e.g. tris(phenanthroline)iron(II) (TPFeII)) or anions (e.g. Fe(CN) 6 -3 , (FeCN) are loaded into anionic, neutral and cationic hydrogels showing no Donnan exclusion effects. The cyclic voltammetry of the loaded species show a quasireversible electron transfer mechanism (E qre ). The electrochemical parameters (diffusion coefficient and charge transfer constant) inside hydrogels are measured using chronoamperometry and digital simulation of the cyclic voltammetry. The Stokes-Einstein equation is used to calculate the effective viscosity of the hydrogel matrixes using the diffusion coefficients of redox complexes determined inside the hydrogels and in aqueous solutions (of known viscosities). The calculated viscosities correlate, with a negative slope, with the swelling rate constant of the hydrogel matrix. The heterogeneous charge transfer constants correlate with the calculated viscosities, revealing the effect of solvent dynamics on the charge transfer, according to Marcus theory for strongly adiabatic electron transfer. In that way, it is shown that the electrochemical measurements are able to monitor the local solvation properties of the hydrogel matrix. The method can be applied in electrochemical sensing of environmental contaminants. In the case of nitrite, the charge transfer is slow on glassy carbon (GC) electrodes. Therefore a redox catalyst (TPFeII) and nitrite are simultaneously absorbed in an anionic hydrogel and the redox electrocatalysis occurs inside the hydrogel matrix. On the other hand, the sensing of arsenite is made using Co oxide nanoparticles adsorbed on the GC electrode with arsenite loaded inside the hydrogel.

K. W. WILLMAN, R. D. ROCKLIN, R. NOWAK et al.

Chemischer Informationsdienst • 1981

Abstract Unter Verwendung von 4‐(MethyldichlorsilyD‐butyrylchlorid können nach aufgezeigtem Schema in Abhängigkeit von den Reaktionsbedingungen Aminophenylferrocen und Tetrakis‐(p‐aminophenyl)‐porphyrin kovalent an glasartige Kohlenstoff‐ und oberflächenoxidierte Pt‐Elektroden gebunden werden.

Takuma Matsuo, Dan Sato, Sang-Gyu Koh et al.

ECS Meeting Abstracts • 2022

Physical Reservoir Computing (PRC) has recently attracted significant attention as a computational method suitable for the edge AI computing, which requires both the high performance of information processing and energy conservative operation. There are two standard methods for evaluating PRC performance: the short-term memory (STM) task for the memory capacity and the parity check (PC) task for the nonlinear conversion capacity. We have developed PR device utilizing Faradaic currents generated by the redox reaction of metal ions in ionic liquids (ILs) and the impact of metal ions in ILs on the STM characteristics has been evaluated by comparing the RC device using metal-ion doped IL with that using non-doped (pure) IL [1] . In this study, we investigated the effect of Faradaic current on the STM and PC tasks by extracting the Faradaic current from the output signal when the triangular shaped input voltage pulse was applied to the PR device. It was found out that the peak shaped Faradaic current in the output signal improves not only the memory capacity but also the nonlinear conversion capability. A reservoir device with a transverse Pt/SiO 2 /Pt structure was prepared (Fig. 1) and solvated IL, Cu(Tf 2 N) 2 -Glyme(G3)=1:1 [2] , was provided between the Pt electrodes as a reaction field where electrochemical reaction of Cu actively takes place. In order to prevent unnecessary copper deposition on the top surface of the Pt electrode, all areas other than the Pt electrode tip was covered with SiO 2 . As a result, a structure that allows deposition only between the terminals was realized. Furthermore, to prevent the migration of the IL by the application of an electric field, an IL pool surrounded by a resist wall was formed by patterning a spin-coated photoresist AZ5214E with a thickness of 2 µm. Au/Ti (100/10 nm) was deposited as the contact pad. The device characteristics were evaluated by cyclic voltammetry. In addition, a response of the device to the triangular pulses was investigated by using the B1530A WGFMU (waveform generator / fast measurement unit). STM and PC tasks were used to evaluate the time series data processing ability. In the present study, an artificial time-series data consisting of randomly connected binary data (0 and 1) was input to one of the Pt electrodes as the triangular shaped voltage pulse stream, while the other electrode was grounded. The positive and negative voltages were defined as 2bit data, ‘1’ and ‘0’, respectively. As shown in Fig. 2, triangular voltage pulse streams shown by the blue line were input to the reservoir device, and output current shown by red line was observed. Current peak appears when the polarity of the input signal is switched from positive to negative and vice versa (black arrow), but the peak intensity decreases when application of voltage pulses with the same polarity are continuously repeated. In addition, Cu deposition on the Pt electrode was observed. These results indicate that the origin of the peak is the Faradaic current generated by the electroactive species near the electrode. We divided output current data into two parts; the first half (yellow region), the latter half (green region). The first half corresponds to the rising part of the triangular pulse and involves the Faradaic current. On the other hand, the latter half corresponds to the descending part of the triangular pulse and is more featureless compared with the first half. We found that the accuracy of STM task was much higher when the first half was used. This tendency was also confirmed for the PC task. In PRC based on the concept of virtual nodes using a single physical device [3] , the output signal complexity is considered to be related to the multidimensional transformation capability, which is one of indispensable property for PRC [4] . The present results suggest that the redox reaction of electroactive species in the IL increases the complexity of the output signal and improves the ability to extract time-series features. We thank Mr. Hiroshi Sato for supporting device fabrication processes. A part of this work was supported by "Nanotechnology Platform Program", Grant Number JPMXPF21NM0006. [1] D. Sato et al ., MEMRISYS 2021, 4A-7 (2021). [2] H. Yamaoka et al ., Chem. Lett., 46, 1832-1835 (2017). [3] L. Appeltant et al ., Nat. Commun., 2, 468 (2011). [4] L. Appeltant et al ., Sci. Rep., 4, 3629 (2014). Figure 1

Ben Dlugatch, Yogendra Kumar, Ran Attias et al.

Journal of The Electrochemical Society • 2025

Abstract The chemistry of the electrolyte solutions that enable reversible Mg deposition is not trivial. Such solutions are currently limited to ethereal solvents and most of them contain chlorides complexes. These ionic complexes have important role in the performance. However, the presence of chlorides in these solutions complicates the cathode side because such solutions are not compatible with the commonly used metallic current collectors for cathodes. Consequently, it is questionable whether it is possible to synthesize fully functional Cl-free electrolyte solutions suitable commercial Mg-ion batteries. Noked et al. reported that by adding DME to the precursor electrolyte [Mg2Cl3*6THF]+ [Ph3AlCl]- in THF, it was possible to create a new electroactive complex Mg salt, namely, [Mg-3.DME]2+ 2[AlPh3Cl]-, which solution performs better than the precursor’s solution. This solution introduces a new case of chlorides free electrolyte solution, with stabilized Mg2+ cations and anions containing chloride ligands which cannot lead to corrosion phenomena. In this work a full evaluation of selected electrolyte solution was carried out, considering rigorously the role of the electroactive species and the anion complexes in the electrochemical process. 
In addition, we study the effect of the anion on the electrochemical performance by comparing this solution with other previously presented solutions.

P. Stonehart, H. A. Kozlowska, Brian Evans Conway

Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences • 1969

The relation between reaction rate and potential (or time) for electrochemical surface processes occurring under potentiodynamic control (linear potential-time programme) has been investigated with particular reference to the behaviour of thin surface oxide films on noble metals. The kinetics of processes involving adsorbed electroactive species are treated for several model cases; the rate equations are developed for mechanisms involving various reaction orders or for processes involving adsorbed reactant interactions and surface heterogeneity effects. By examination of the dependence of the reaction rate (current) with time and the effect of potential scan rate, v , on the maximum reaction velocity and the potential at which it occurs, the models may be distinguished. In this manner, the inter­dependence of v and the reaction velocity constants k a and k c for the anodic oxidation and the cathodic reduction processes respectively, can be quantitatively established. The relation between quasi-equilibrium situations where the reverse reaction is significant and irreversible situations where it is not can be demonstrated. Heterogeneity terms introduced into the kinetic relations express deviations from Langmuir adsorption behaviour and may be an intrinsic property of the substrate surface or a property of the adsorbed reactant (induced heterogeneity). Applications of the treatment are made to reduction of surface oxide species at the noble metals and the significance of hysteresis and time effects in the processes of electrochemical formation and reduction of surface oxide at platinum, rhodium, iridium and palladium is investigated.

Kazuko Ogino (née Ebata), Nobuyuki Tanaka

Bulletin of the Chemical Society of Japan • 1966

Abstract The one-electron reduction wave of hexamminechromiuni(III) ions at the dropping mercury electrode splits into two steps by the presence of manganese (II) and ethylenediaminetetraacetato-manganate(II) (MnY2−; Y4− represents a quadrivalent ethylenediaminetetraacetate anion) ions. The limiting current of the first step was considered to depend on the rate of the formation of CrY2− by the substitution reaction of MnY2− and chromium(II) ions which were produced at the electrode by the reduction of the chromium(III) complex ions. From the change in the limiting current of the first step by the change of the concentrations of Mn2+, MnY2− and H+ the rate constants of the complex-forming reaction (Remark: Graphics omitted.) were obtained to be K1f=8×107 l.mol−1sec−1,K1b=4×104 l.mol−1sec−1 (ionicstrength 1.0, 25°C)

Luis Angel Contreras-Pimentel, Hiram Hernández-López, Ismailía L. Escalante-García et al.

ECS Meeting Abstracts • 2018

The generation of energy from renewable sources (solar and wind) is limited by the weather conditions that turn them into intermittent sources. In addition to this, and due to the large amount of energy produced while minimum demand, energy storage technologies are urgently needed. Redox flow batteries (RFBs) are a very attractive technology for large-scale energy storage [1]. Currently RFB systems are mostly based on redox reactions of electroactive metal ions, which are limited by their abundance, low solubility, high cost and toxicity. However, organic species have generated great interest [2]. Quinones are the main organic redox active species that have a key role in the electron transport processes of biological systems depending on molecular aromaticity and their electronic structures [3]; for example, the synthesis of ATP and photosynthesis [4]. However, the synthesis of redox species based on quinone analogs for RFB is associated with the unnecessary factor of human and monetary capital. Therefore, the current computer tools allow great opportunities to screen for valuable quinone species for RFB, as well to optimize resources. In this work, a chemical system derived from quinones was proposed as possible electroactive species as redox electrolyte for energy storage applications (Figure 1). Computer calculations of the chemical system were carried out to determine the difference in eV between HOMO-LUMO (Egap) in order to predict their electron transfer ability, as well, the relationship towards their redox properties for RFB applications. First, the molecules shown in Figure 1 were modeled in the program molden to obtain the z matrices. Then, theoretical calculations were performed by Gaussian v.0.9 using the functional hybrid B3LYP with the base 6-311 + G (d, p) in order to obtain the difference of eV between the HOMO-LUMO of the molecules. Subsequently, t he proposed molecules were synthesized by Michael addition of 1,4 (DNQ1-6) using substituted anilines. Here, the synthesis reactions were carried out at 70°C for 12 h. On the other hand, the triazole in the DNQ8 was synthesized by means of a catalyzed 1,3-dipolar addition cycle of Huisgen. Electrochemical Studies were carried out by cyclic and linear voltammetry to evaluate the redox reactions, reversibility and the diffusion coefficients in order to confirm the theoretical calculations of the proposed system. The theoretical calculations results showed that all materials have a lower E gap compared to their predecessor NQ (E gap =3.984eV), Figure 1. Therefore, it is possible to say that the DNQ1-8 compounds are suitable as redox electrolyte for flow batteries since at lower E gap higher electrical conductivity, according to the theory of frontier molecular orbitals [5]. Particularly, the DNQ3 and DNQ6 presented the lowest E gap , thus, these compounds could be a very attractive option for a fast electron transfer at the electrode/electrolyte interface in a RFB. All the molecules proposed in Figure 1 were synthesized as describe above. The yields were from 63% to 81%. The molecules synthesized with chlorinated reagents exhibit the highest yield and it was attributed to the presence of a better leaving group. UV-vis studies were performed to support the correspondence of the E gap by theoretical calculations. For instance, a batochromic shift of the interactions η → π * was observed at 480 nm approximately for the DNQ1 as compared to this for the DNQ3 at 540 nm approximately. These preliminary results agreed with the theoretical calculations, higher E gap for the DNQ1 as compared to lower E gap for the DNQ3. Overall, the proposed system seems to be suitable for energy storage applications in RFBs, however, electrochemical studies are being carried out and will be presented at the conference in order to confirm these results. References Skyllas-Kazacos, M., Chakrabarti, M. H., Hajimolana, S. A., Mjalli, F. S. & Saleem, M. “Progress in flow battery research and development”, J. Electrochem . No. 158, p. R55-R79 (2011). Song, Z. & Zhou, H. “Towards sustainable and versatile energy storage devices: an overview of organic electrode materials”, Energy Environ . No. 6, p. 2280–2301 (2013). Ding, Y., Li, Y. & Yu, G. “Exploring bio-inspired quinone-based organic redox flow batteries: a combined experimental and computational study”, Chem No.1, p . 790–801 (2016). Quan, M., Sanchez, D., Wasylkiw, M. F. & Smith, D. K. “Voltammetry of quinones in unbuffered aqueous solution”, J Am Chem Soc . No. 129, p. 12847–12856 (2007). Tsuji, Y. & Hoffmann, R. “Frontier orbital control of molecular conductance and its switching”, Chem. Int. Ed. Engl. No. 53, p. 4093–4097 (2014). Figure 1

Michael J. Honeychurch, Michael J. Ridd

Electroanalysis • 1995

Abstract A theory to describe the enhancement of the transition time and change in peak shape for the chronopotentiometric reduction of an adsorbed species caused by the reduction of an electroactive diffusing species is presented. The equations were derived for planar, cylindrical and spherical electrodes and verified for the chronopotentiometric reduction of adsorbed cystine, as mercurous cysteine thiolate, on a hanging mercury drop electrode in the presence of dissolved oxygen.

A. Robert Hillman, Mohamoud A. Mohamoud, Stanley Bruckenstein

Electroanalysis • 2005

Abstract The mobile species (ion and solvent) content of permselective electroactive films can be represented in 3D compositional space, where the three components are potential ( E ), charge ( Q ) and solvent population ( Γ S ). Having introduced this concept for films undergoing redox switching under thermodynamic control with ideal solvation characteristics, it was previously shown how one could introduce the additional complexity of non‐ideal solvation characteristics, or slow charge (electron/ion) transfer kinetics, or slow solvent transfer kinetics. Here, the facility is developed to incorporate any combination of these complexities, providing a more realistic model for “typical” electroactive films. Additionally, the possibility of “asymmetry” in the entry and exit rates of mobile species is considered. A range of specific kinetic and thermodynamic scenarios is explored for a cyclic voltammetric potential control function and represented in ( E , Q, Γ S )‐space and through solvent:ion flux ratios. These integral and differential compositional representations are directly applicable to experimental data from a wide range of in situ techniques and allow simple visualization and qualitative recognition of specific behavioral types. The responses vary significantly with potential scan rate, underscoring the value of varying experimental timescale in order to highlight specific phenomena and thereby evaluate the relevant thermodynamic or kinetic parameters.

Takuya Okazaki, Masaki Yoshioka, Tatsuya Orii et al.

Electroanalysis • 2023

Abstract We present an electrochemical‐lossy mode resonance (LMR) sensing method that detects refractive indices and electroactive species. The LMR peaks of indium‐tin‐oxide in the transmittance‐wavelength spectra were significantly shifted as the applied potential between 1.0 and −0.5 V at 209 nm/V. The modulation was exploited for sensing the refractive index and electroactive species (ferrocyanide and methylene blue) in two ways: peak‐wavelength tracking and potential scanning. The potential‐scanning technique produced clear potential LMR peaks in the transmittance‐potential spectra for the first time, which were corresponded to the external refractive index. Meanwhile, the limits of detection of ferrocyanide and methylene blue were 7.5 and 25.3 μM, respectively, in peak‐wavelength tracking and 18.2 and 20.8 μM, respectively, in the potential scanning technique.

Christopher B. Gorman

Advanced Materials • 1997

The role of a dendrimer as an encapsulating shell around small molecules or the dendrimer core itself are briefly outlined. It is shown that encapsulation by a dendrimer reduces the rate of electron transfer to or from a redox‐active moiety incorporated in the core according to the degree of branching around the core. Development of this idea could lead to a molecular switch or an information storage device. The use of the properties of the core in order to obtain information about the shape, internal organization, and environment within a dendrimer is also outlined and an example given.

L. R. Dalton

MRS Proceedings • 1987

ABSTRACT A general scheme for the preparation of soluble electroactive polymers is reviewed with emphasis that polymers so prepared permit investigation of the effects of π-electron delocalization and lattice charge upon nonlinear optical activity. Particular attention is focused upon six membered ring polymer derivatized in 1,4 positions with vinylamine substituents. Such substituents influence rates of polymerization reactions and electronic properties as well as solubility. Preliminary measurement of χ (3) for as-synthesized polymers is effected by DFWM.

, Homayoun Jamasbi, Yen Wei

• 2001

Electroactive polymers have been identified as novel corrosion inhibiting coatings for metals. Among all the electroactive polymers studied so far, polyaniline is the first to achieve commercial availability. However, one problem associated with large-scale commercial applications is the limited processibility. Furthermore, among the inherent drawbacks is the non-unity polydispersity in molecular weight and the existence of structural defects. Another potential problem with polyaniline is poor adhesion to metal substrates. Aniline oligomers, on the other hand, could be prepared in well defined structures with unity or near unity polydispersity. They demonstrate enhanced solubility and processibility due to lower molecular weight. End groups could be varied to different functional groups and as a result various polymeric derivatives of aniline oligomers could be prepared. The epoxy cured amino terminated aniline has demonstrated excellent adhesion to cold rolled steel, and a far better performance than polyaniline. In this thesis, for the first time, we have performed a series of systematic comparative exposure studies containing various aniline oligomers and their epoxy cured derivatives both as coatings and as additives against the best of commercially available conventional systems. We have successfully demonstrated the superior corrosion protection properties of aniline oligomers and their epoxy cured derivatives for practical, industrial applications. In particular, the epoxy cured amino terminated aniline trimer demonstrated outstanding corrosion protection property at low film thickness. We performed the exposure tests based on the two widely accepted industrial standards per ASTM (AMERICAN SOCIETY FOR TESTING AND MATERIALS). They are: ASTM B 117-97 (Standard Practice for Operating Salt Spray (Fog) Apparatus), and ASTM D 5894-96 Cyclic Salt Fog/UV Exposure of Painted Metal, (Alternating Exposures in a Fog/Dry Cabinet and a UV/Condensation Cabinet). In order for the data to have universal acceptance, there are also grading and interpretation requirements based on ASTM. Therefore, we used ASTM D 1654-92 (Standard Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments).

L. H. Han, T. J. Lu

Volume 1 • 2004

Electroactive polymers (EAPs), such as piezoelectric polymer, polyelectrolyte gels, dielectric elastomer and conducting polymer etc., are emerging as a new type of actuation materials for a broad range of actuator and transducer applications, because of their higher strain, higher response and higher efficiency. Acrylic elastomer films have demonstrated higher specific energy density (0.4J/g) and more than 100% actuated strains, and have been recommended for the artificial muscle actuators. Much research has been carried out to investigate the actuation properties of EAP films, however, little information is available for the mechanical properties of EAP films, which are crucial for designing EAP actuators. This work focuses on developing a means of characterizing the mechanical properties of EAP thin film materials, describing the mechanical behavior with the suitable constitutive models and determining the material parameters for the development of actuators. To measure the mechanical properties of EAP films, a uniaxial testing system is developed, which consists of a small-scale force transducer, a CCD camera, a National Instruments card and a laser displacement transducer. The loading and unloading cycles on film specimens are controlled by an Instron Machine. The applied force and the total are stored in the computer by the National Instrument card. A sequence of 2D images are recorded by the CCD camera to capture the deformation process of the film sample. Then, the displacements of the marks on the film surface vertical to the thickness plane are calculated from the sequential images by image analysis techniques. There are several well-known models available to describe the mechanical behaviors of the EAP films, such as Neo-Hookean, Mooney-Rivlin and Ogden models etc. To determine the most suitable constitutive models and corresponding material constants, a generalized method based on finite element analysis is proposed and implemented by interfacing with ABAQUS finite element package. The kernel of the method is to minimize the difference between the measured displacement field and the computed displacement field. A global optimisation algorithm, simulated annealing (SA), is used to minimize the objective. The experimental investigation on the mechanical properties of the dielectric elastomer film (VHB4910) is presented as an example to demonstrate the functions of the testing system and the developed method. The developed testing system and method can also be used for characterizing the mechanical properties of other EAP film materials.

Tian-Bing Xu, Ji Su

Aerospace • 2004

An electroactive polymer-ceramic hybrid actuation system (HYBAS) was recently developed. The HYBAS demonstrates significantly-enhanced electromechanical performance by utilizing advantages of cooperative contributions of the electromechanical responses of an electrostrictive copolymer and an electroactive single crystal. The hybrid actuation system provides not only a new type of device but also a concept to utilize different electroactive materials in a cooperative and efficient method for optimized electromechanical performance. In order to develop an effective procedure to optimize the performance of a hybrid actuation system (HYBAS), a theoretical model has been developed, based on the elastic and electromechanical properties of the materials utilized in the system and on the configuration of the device. The model also evaluates performance optimization as a function of geometric parameters, including the length of the HYBAS and the thickness ratios of the constituent components. The comparison between the model and the experimental results shows a good agreement and validates the model as an effective method for the further development of high performance actuating devices or systems for various applications.

Nirmal Singh Mahar, Kartik Aiyer, Juwayria et al.

Microbiology Resource Announcements • 2023

The draft genome sequence of Delftia sp. is reported here. The genome was recovered from a mixed-species electroactive community in a microbial fuel cell that had been inoculated with wastewater from the Indian Institute of Technology Delhi, India. Sequencing was performed using Nanopore technology.

, Jana Marie Wächter

• 2024

Bacterial biofilms are polymicrobial aggregates embedded in a self-produced matrix, which consists of extracellular polymeric substances (EPS). In a clinical context, bacterial biofilms are related to the development of chronic infections. Notably, their unique properties confer persistence in host niches despite antimicrobial treatment and the host immune response, where their distinct virulence exacerbates disease progression. In vitro models for bacterial biofilms have been developed. Simple models typically provide artificial growth environments, resulting in biofilm development diverging from in vivo biofilms. Consequently, sophisticated models incorporate growth conditions mimicking the environment of chronic infections. Still, they lack host cells, as the pathogenic bacteria cause cytotoxic effects during biofilm formation. In this context, electrospinning represents a promising approach, due to the ability to design nanofibrous scaffolds that closely mimic biological matrices, while maintaining mechanical strength for non-destructive handling in in vitro experiments. The objective of this thesis was to develop an in vitro biofilm model for chronic wound infections based on electrospun scaffolds, offering high clinical relevance through its close representation of in vivo conditions, the capacity to explore host-biofilm interfaces, and the incorporation of multiple bacterial species within a single biofilm. Three-dimensional electrospun scaffolds of cellulose acetate (CA) and gelatin were fabricated as scaffolds for biofilm development. The scaffolds were designed to possess composition and physicochemical properties similar to native biofilm microenvironments. Furthermore, high mechanical strength was required to enable the transfer of mature biofilms. The CA-based scaffolds, alone and in combination with gelatin, fulfilled the necessary criteria for physicochemical properties. Gelatin fiber scaffolds were limited due to rapid dissolution in aqueous environments. P. aeruginosa colonization of CA scaffolds did not result in three-dimensional model systems. In contrast, fiber scaffolds of CA and gelatin promoted bacterial distribution throughout their entire dimensions and enabled matrix production. Along with the formation of aggregates and a dense biofilm morphology, this confirmed their maturation. Their high antibiotic tolerance demonstrated the functional properties of mature biofilms. Subsequently, the high mechanical strength of the biofilm models on blend scaffolds enabled the transfer of mature biofilms to ex vivo human skin wounds, imitating a chronic state of wound infection. The novel biofilm model based on nanofibrous scaffolds addressed the major limitations of existing biofilm models by mimicking the native microenvironment of infectious biofilms and facilitating the examination of biofilm-host interfaces. In the next step, the developed biofilm model system was used to evaluate host biofilm interactions. For this study, in vitro and ex vivo models of human skin wounds were infected with pre-cultivated biofilms of P. aeruginosa. Regarding the structural characterization of biofilm infected wound models, all models enabled biofilm growth in close contact to the wound bed, creating ideal conditions for biofilm host interactions. In the case of viable wound models, an active immune response was demonstrated with cytokine gene expression patterns consistent with in vivo observations. Furthermore, the tissue viability was found to impact bacterial colonization behavior in the wound bed. These observations underscored the relevance of using viable models for studying direct biofilm-host-interactions. The new biofilm model, combined with human wound models of various complexities, demonstrated its applicability across a spectrum of research fields, from basic investigations to translational approaches. Biofilms in persistent wound infections typically exhibit a polymicrobial nature. Previous investigations have largely concentrated on single species due to the challenges of co-cultivating biofilms of multiple pathogens in vitro. P. aeruginosa and S. aureus were selected to create mono and dual-species biofilms. P. aeruginosa mono-species biofilms and dual-species biofilms exhibited rapid biofilm development. In contrast, the development of S. aureus biofilms was delayed. Initially, the presence of P. aeruginosa stimulated the adhesion of S. aureus in the dual-species biofilms. However, P. aeruginosa became increasingly dominant, revealing both cooperative and competitive interactions. In dual-species biofilms, both species existed in close proximity, essential for interbacterial interactions. All models exhibited high tolerance to antibiotic treatment. The biofilm matrix acting as a penetration barrier was demonstrated as a major factor. Constituents of P. aeruginosa mono-species and dual-species biofilms impaired wound healing by stimulating host immune responses and reducing cell viability. In contrast, S. aureus biofilms appeared to exhibit proliferative effects with no impairment of wound healing. The biofilm model facilitated the co-cultivation of multiple species in one biofilm, underscoring its similarity to the in vivo environment.

K Di Gleria, C.M Halliwell, C Jacob et al.

FEBS Letters • 1997

A cysteine residue was introduced close to the active site of β‐lactamase I by site‐directed mutagenesis to replace tyrosine‐105 and was subsequently modified with an electroactive SH‐specific reagent, N ‐(2‐ferrocene‐ethyl)maleimide. The resulting modified enzyme became electroactive, showing good quasi‐reversible electrochemistry which was characteristic of the attached ferrocene moiety while retaining its specific enzymatic activity. In the presence of a suicide substrate, 6β‐iodopenicillanic acid, the redox potential shifted +20 mV suggesting that the label was sensitive to changes in the active site of the enzyme.

, Brenda Guadalupe Molina García

• 2020

Development of polymeric biomaterials with tailored properties is essential for expanding biotechnologies and, therefore, proposing novel solutions for diagnostic and treatments in modern medicine. In order to contribute with such expansion, this research suggests different strategies to modify intrinsically conducting polymers (ICPs) and overcome their few limitations. Three main engineering approaches were used to combine ICPs advantages with others from conventional insulating polymers and biopolymers, optimizing their performance as electrochemical biomaterials on tissues engineering, biomimetic platforms, actuators and specially on the biosensing field. The first strategy evaluated in this Thesis was designed to take advantage of the “grafting-through”technique and prepare graft copolymers with ICPs backbones. The incorporation of well-known biocompatible polymers like polyethylene glycol (PEG) and polycaprolactone (PCL) into ICP backbones, increased the cell viability in presence of the synthetized copolymers. Such modifications and the ICPs electroactivity allowed to estimate the copolymers performance as electrochemical sensors of biomolecules. The second approach was planned to prepare free-standing, flexible and electroactive films for the electrochemical detection of bacterial infections. The excellent mechanical properties of isotactic polypropylene (i-PP) plastic, combined with an ICP like poly (3,4-ethylendioxythiophene) (PEDOT), enabled the obtained a novel composite with good dimensional stability to be applied as electrochemical platform for bacterial detection. This composite was able to perceive extracellular nicotinamide adenine dinucleotide (NADH), generated from the respiration reactions of bacteria, and distinguishing prokaryotic microbes from eukaryotic cells. In addition, with a small adjustment, the generated films exhibited qualities as electroactive bioplatforms for tissue engineering. Finally, the third strategy fashioned an electroactive multi-functional nanomembrane for applications of flexible biomedical implants. A layer-by-layer assembly (LbL) was used to integrate the PEDOT electroactivity to the poly(lactic acid) (PLA) biopolymer. The self-supported nanomembrane of 5 layers, showed benefits as biomimetic platforms for selective ion and ATP transport, as well as actuator/artificial muscles. Overall, the characterization studies of the electroactive and biocompatible composites presented in this Thesis, offer a comprehensive view on how modifications in ICPs optimize its abilities as biomaterials and open a wide range of possible applications in biomedicine. El desarrollo de biomateriales poliméricos con propiedades específicas, es esencial para la expansión biotecnológica y, por lo tanto, para el diseño de soluciones novedosas en el diagnóstico y tratamientos de enfermedades en la medicina moderna. Con el objetivo de contribuir con dicha expansión, esta investigación propone diferentes estrategias de modificación en polímeros conductores intrínsecos (ICPs por sus siglas en ingles), y superar con ello sus pocas limitaciones. Tres principales enfoques de ingeniería fueron utilizados para combinar las ventajas de ICPs con las de otros polímeros convencionales y biopolímeros, optimizando su rendimiento como biomateriales electroquímicos en ingeniería de tejidos, plataformas biomiméticas, actuadores y, especialmente, en el campo de la biodetección. La primera estrategia evaluada en esta Tesis, fue diseñada para aprovechar la técnica de injerto y preparar copolímeros con una cadena principal de ICP. Empleando esta técnica, la incorporación de polímeros biocompatibles, como el polietilenglicol (PEG) y la policaprolactona (PCL), en la cadena principal de un ICP, aumentó la viabilidad celular en presencia de los copolímeros formados. Dichas modificaciones y la electroactividad de los ICPs, permitieron estimar el rendimiento de los copolímeros como sensores electroquímicos de biomoléculas. El segundo enfoque fue planeado para preparar películas auto soportables, flexibles y electroactivas, que permitieran la detección electroquímica de infecciones bacterianas. Las excelentes propiedades mecánicas del polipropileno isotáctico (i-PP) en combinación con un ICP, como el poli (3,4-etilendioxitiofeno) (PEDOT), permitieron obtener un nuevo compuesto electroquímico capaz de percibir el dinucleótido adenina de nicotianamina (NADH por su siglas en ingles), generado extracelularmente durante las reacciones respiratorias de las bacterias, y distinguir los microbios procariotas de las células eucariotas. Además, con un pequeño ajuste, las películas generadas exhibieron cualidades como bioplataformas electroactivas para la ingeniería de tejidos. Finalmente, con la tercera estrategia se diseñó una nanomembrana electroactiva multifuncional, para aplicaciones de implantes biomédicos flexibles. Un ensamble de capa por capa, fue utilizado para integrar la electroactividad del PEDOT con el biopolímero ácido poli láctico (PLA por sus siglas en ingles). La nanomembrana auto soportable de 5 capas, mostró beneficios como plataforma biomimética para el transporte selectivo de iones y adenosín trifosfato; o como músculos artificiales o actuadores. En general, los estudios de caracterización de los compuestos electroactivos y biocompatibles presentados en esta Tesis, ofrecen una visión integral de cómo las modificaciones en los ICPs optimizan sus capacidades como biomateriales, y abren una amplia gama de posibles aplicaciones en biomedicina.

Sandra Mendoza, Eduardo Castaño, Yunny Meas et al.

Electroanalysis • 2004

Abstract In this work, we present a method to analyze the voltammetric response of reversible redox systems involving molecules that, bearing m non‐interactive electroactive sites, can undergo fast complexation equilibria with host molecules present at concentrations of the same order of magnitude as those of the electroactive guest. The approach focuses on systems for which the relative values of the binding constants for the oxidized and reduced forms of the guest result in the displacement of the voltammetric response of the electroactive molecule as the concentration of the host is increased in the electrolytic solution. This behavior is commonly known as “one wave shift behavior”. Based on a series of assumptions, the method allows calculation of all the thermodynamic parameters that describe the electrochemical and complexation equilibria of a given host‐guest system. The main strength of the suggested method, however, relies on the fact that it only requires cyclic voltammetry data and that it can be used for systems in which large concentrations of the host can not be employed either due to important changes of the ionic strength or to solubility problems. Although the accuracy of the obtained information is limited by the quality of the data provided by the technique, and by the assumptions employed, it certainly represents an excellent starting point for subsequent refinement either using digital simulations or an independent experimental technique.

, Napat Charoonrak

• 2013

Electroactive shape memory composites are smart materials that change their shapes and recover their initial shapes in the presence of an applied electric field. In this work, the focus is on fabricating an electroactive shape memory composite consisting of iron (Ill) chloride doped poly(p-phenylene)(PPP)/crosslinked poly(ε-caprolactone) (cPCL) using benzoyl peroxide (BPO) as a crosslinking agent. In addition, thermal property, electrical conductivity, and electromechanical properties of the composite as a function of crosslinking ratio. doping level, and concentration of embedded PPP are investigated. The electromechanical properties show that 3%wt BPO cPCL gives the highest storage modulus response and electrical sensitivity. However, the electrical sensitivity decreases dramatically at 0.01%v/v of embedded PPP because of the increasing of initial storage modulus. Then start to increase with increasing the concentration of PPP which can be attributed to the increases of dipole moment induction in the presence of an external electrical stimulation.

, Tenille Herd

Queensland University of Technology • 2024

Organic redox flow batteries are a type of energy storage technology that uses organic molecules in a pumped organic solvent system to operate. The use of organic materials reduces our reliance on metals and disturbing the environment. Additionally, this technology could aid the widespread adoption of renewable energy technologies as part of an approach to address the climate change crisis through the use of cheap feedstock. In this work, a number of studies were conducted to assess organic compounds for their suitability for use as catholyte material within an organic redox flow battery.

Guiqin Yang, Luchao Han, Junlin Wen et al.

International Journal of Systematic and Evolutionary Microbiology • 2013

A Gram-negative, straight to slightly curved rod-shaped bacterium, motile with peritrichous flagella, designated SgZ-6 T , was isolated from an electroactive biofilm and was characterized by means of a polyphasic approach. Growth occurred with 0–5.0 % (w/v) NaCl (optimum 1 %), at pH 6.0–10.0 (optimum pH 7.0) and at 10–42 °C (optimum 30 °C) in trypticase soya broth. Phylogenetic analyses based on the 16S rRNA and gyrB genes identified the isolate as a member of a novel species of the genus Pseudomonas . Strain SgZ-6 T exhibited the highest 16S rRNA gene sequence similarity to ‘ Pseudomonas linyingensis ’ CGMCC 1.10701 (97.5 %), followed by Pseudomonas sagittaria JCM 18195 T (97.4 %), P. oleovorans subsp. lubricantis DSM 21016 T (96.6 %), P. tuomuerensis JCM 14085 T (96.5 %) and P. alcaliphila JCM 10630 T (96.4 %). Strain SgZ-6 T showed the highest gyrB gene sequence similarity of 93.7 % to ‘ P. linyingensis ’ CGMCC 1.10701 among all type strains of genus Pseudomonas . DNA–DNA pairing studies showed that strain SgZ-6 T displayed 47.1 and 40.3 % relatedness to ‘ P. linyingensis ’ CGMCC 1.10701 and P. sagittaria JCM 18195 T , respectively. The major isoprenoid quinone was ubiquinone 9 (Q-9). The whole-cell fatty acids consisted mainly of summed feature 3 (C 16 : 1 ω6 c and/or C 16 : 1 ω7 c ), C 16 : 0 and summed feature 8 (C 18 : 1 ω6 c and/or C 18 : 1 ω7 c ). The DNA G+C content of the genomic DNA was 68.1 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain SgZ-6 T is proposed to represent a novel species of the genus Pseudomonas , for which the name Pseudomonas guangdongensis sp. nov. is proposed. The type strain is SgZ-6 T ( = CCTCC AB 2012022 T = KACC 16606 T ). An emended description of the genus Pseudomonas is also proposed.

Yue Dong, Peifang Wang, Yixuan Zhang

IOP Conference Series: Earth and Environmental Science • 2020

Abstract Microbial electrochemical systems (MESs) are a promising clean energy source to directly convert waste chemicals in domestic wastewater to available electric power with synchronous pollutant removal. The physiological and biochemical behaviors of electroactive microorganisms (EAMs) is the key factor of the MESs. Dibutyl phthalate (DBP), as the emerging pollutant, widely exists in municipal wastewater which has strong ecological toxicity. So, utilization of MESs in the engineering practice of wastewater treatment must consider the impact of DBP on the physiological and biochemical behaviors of electroactive biofilm. The output voltage and power density of the MES decreased significantly with the increase of DBP in the synthetic wastewater. In addition, the EAMs resisted the stimulation of DBP by secreting more extracellular polymer substances (EPS) by microscopic observation. The composition and structure of the EPS also changed, mainly reflected in the increase of β-polysaccharide content and the expansion of its coverage area.

John Fuerst

Microorganisms • 2014

The MDPI journal Microorganisms is still very young, having been launched in 2013, but the concept of the microorganism has been in use for at least a century as a unifying principle for the discipline of microbiology, which was cemented firmly by the intellectual work of Roger Stanier and colleagues in their Microbial World and other general microbiology textbooks and related articles from the 1950s to the 1970s [1,2]. Merging the idea of the microscopic and the very small with the older idea of an organism as a living entity or cell, the concept of a microorganism enabled a real appreciation of the microbial world as one that is amenable to study using similar tools and approaches even though representing distinctly different types of reproductive units and cell organizations. In the late 20th century following the work of Carl Woese and other molecular evolutionists, biologists came to appreciate the commonality among all organisms, all being comprised of cells that bear a remarkable similarity to one another and that share a common evolutionary ancestry, and consequently with major features of a largely shared genetic code and molecular biology. In this sense microbiology and biology as a whole became unified as they never had been before.[...]

John Fuerst

Microorganisms • 2013

It is my great pleasure to welcome you to Microorganisms, a new open access journal, which is dedicated to microorganisms in all their forms and via any approach to their study. [...]

, Yi Guo, Yen Wei

• 2007

Novel electroactive nanostructured polymers and organic-inorganic hybrid materials have been successfully developed for electrochemical, sensory, and tissue engineering applications. For this new class of materials, electroactivity was introduced into silica matrix through the incorporation of a silsesquioxane precursor, N,N'-bis(4'-(3- triethoxysilylpropyl-ureido)phenyl)-1,4-quinonenediimine (TSUPQD). As a derivative of emeraldine form of aniline trimer, TSUPQD was synthesized from the reaction between one equivalent of aniline trimer and two equivalents of triethoxysilylpropyl isocyanate (TESPIC) and characterized by spectroscopic methods, such as FTIR, UV-Vis, MS, NMR, and XRD. The electrochemical behavior of TSUPQD was studied by cyclic voltammetry showing two distinct oxidative states in a reversible cyclic voltammogram after doping with a protonic acid. The intrinsic electroactivity of TSUPQD is similar to polyaniline was maintained. With the presence of two triethoxylsilane groups on each TSUPQD molecule, related mesoporous electroactive hybrid materials were prepared through surfactant templated sol-gel process. The resultant hexagonally patterned porous structures were studied by BET and TEM. The materials have large surface areas and pore volumes with pore diameters ranging from 2.1 to 2.8 nm. Porous structures give rise to improved electroactivity compared to their nonporous counterparts. Multicolor silica nanospheres were prepared by coating TSUPQD onto silica surface via intermolecular condensation reaction. By varying the particle size, surface area, and organic dopant, the nanospheres exhibit multiple colors. Furthermore, luminescent nanospheres were prepared when fluorescent organic acid was employed as dopant. These nanospheres demonstrated the promising potential as sensory materials for hydrazine detection. Electroactive self-assembled monolayers were evenly attached on glass substrates, followed by covalent bonding of an adhesive oligopeptide, i.e., cyclic RGD, on the aromatic amine terminals. The biocompatibility evaluation on resultant structures from PC12 neuronal cell cultures demonstrated that this bio-derivatized substrate well supported the cell adhesion and proliferation. It is more significant that this electroactive surface stimulated spontaneous neuritogenesis of PC12 cells. Electrospun PANI-contained gelatin fibers were also investigated as conductive scaffold for tissue engineering purposes. SEM analysis of the blend fibers containing less than 3 wt% PANI revealed uniform fibers with no evidence for phase segregation. DSC studies confirmed this result. To test the utilization of PANI-gelatin blends as a fibrous matrix for supporting cell growth, H9c2 rat cardiac myoblast cell cultures were evaluated in terms of cell proliferation and morphology.

Paul J. Weimer

Microorganisms • 2022

As major structural components of plant cell walls, cellulose and hemicellulose are degraded and fermented by anaerobic microbes in the rumen to produce volatile fatty acids, the main nutrient source for the host. Cellulose degradation is carried out primarily by specialist bacteria, with additional contributions from protists and fungi, via a variety of mechanisms. Hemicelluloses are hydrolyzed by cellulolytic bacteria and by generalist, non-cellulolytic microbes, largely via extracellular enzymes. Cellulose hydrolysis follows first-order kinetics and its rate is limited by available substrate surface area. Nevertheless, its rate is at least an order of magnitude more rapid than in anaerobic digesters, due to near-obligatory adherence of microbial cells to the cellulose surface, and a lack of downstream inhibitory effects; in the host animal, fiber degradation rate is also enhanced by the unique process of rumination. Cellulolytic and hemicellulolytic microbes exhibit intense competition and amensalism, but they also display mutualistic interactions with microbes at other trophic levels. Collectively, the fiber-degrading community of the rumen displays functional redundancy, partial niche overlap, and convergence of catabolic pathways that all contribute to stability of the ruminal fermentation. The superior hydrolytic and fermentative capabilities of ruminal fiber degraders make them promising candidates for several fermentation technologies.

, Patcharee Intanoo

• 2010

Elastomers that can respond to external stimuli, such as temperature and electric field, are known as dielectric elastomers, consisting of either a polar molecule or an unsaturated structure on the side chain with induced dipole moments. In our work, we prepared the electroactive polymers from blends of dielectric elastomers and a conductive polymer. For the dielectric elastomers, ethylene propylene diene elastomer (EPDM NORDEL IP 5565) was used as the matrix phase. The conductive polymers, permethylpolyazine (PAZ), were synthesized and doped with iodine at various doping levels for improving the electrical conductivity. The blends were prepared by the mechanical blending of highly doped PAZ particles with EPDM at various particle concentrations from 5 vol% to 20 vol%. The chemical structures of undoped and doped PAZ were characterized by FT-IR. The electromechanical properties were studied under an oscillatory shear mode in the frequency range 0.1-100 rad/s with electric field strength varying from 0 to 1 kV/mm at 27℃. The effects of particle concentration on storage modulus response, G', storage modulus sensitivity, G'/G'0, and electrical conductivity, σ, and dielectric constant, ɛ' at 27℃ and 100 rad/s were also studied. G' and G'/G'0 increase with increasing electric field strength, and particle concentration. The electrical conductivity and dielectric constant increase with particle concentration.

Julio Villena, Haruki Kitazawa

Microorganisms • 2017

In recent decades; scientists have provided encouraging evidence that probiotic microorganisms are valuable in the prevention and treatment of a variety of diseases.[...]

, Shan Cheng, Yen Wei

• 2002

Novel nanostructured porous sol-gel materials, nanocomposites, electroactive and bioapplicable materials have been successfully developed for a wide range of perceivable applications. Several versatile nonsurfactant templated sol-gel pathways have been developed to prepare nanostructured porous materials and composites with different morphologies (e.g., monoliths, nanospheres, nanoparticles, and thin films), structures, compositions and properties. The synthetic conditions were systematically studied and optimized. The template effects on pore structure as well as synthetic process, especially template removal steps, have been investigated. The composition and pore structures were thoroughly studied with various spectroscopic and microscopic methods such as IR, TGA, SEM, TEM, BET and XRD. The obtained mesoporous materials usually exhibit high surface area, large pore volume and narrowly distributed pore diameter. The porosity can be fine tuned simply by adjusting the template concentration. The convenient synthesis as well as the distinctive structure and physical-chemical properties render these sol-gel materials great suitability for a wide range of potential applications, such as chemical and biological sensors, catalysts, drug delivery and functional coatings. Biocompatible and electroactive nanocomposites have been prepared through a biological agent (i.e., collagen) templated chemical polymerization of aniline monomers. The resultant polyaniline-collagen complexes exhibit well controlled doping-dedoping electroactivity and much enhanced solubility. Demonstrated with cell growth studies, the polyaniline-collagen complexes show improved biocompatibility in comparison to polyaniline. The new materials can be used to fabricate scaffolds, with which the effect of electrical stimuli on cell growth and differentiation can be evaluated with the hope of ultimately using electrical signal to stimulate controllable cell and tissue regeneration. Aniline derivative substituted quinoline ligand compounds and their complexes have been prepared and investigated as potential electroluminescent materials.

Zheng-Kai An, Young-Chae Song, Keug-Tae Kim et al.

Fermentation • 2023

Direct interspecies electron transfer (DIET) between electroactive microorganisms (EAMs) offers significant potential to enhance methane production, necessitating research for its practical implementation. This study investigated enhanced methane production through DIET in an anaerobic digester bio-augmented with EAMs. A horizontal anaerobic digester (HAD) operated for 430 days as a testbed to validate the benefits of bioaugmentation with EAMs. Anaerobic digestate slurry, discharged from the HAD, was enriched with EAMs in a bioelectrochemical auxiliary reactor (BEAR) under an electric field. This slurry enriched with EAMs was then recirculated into the HAD. Results showed bio-augmentation with EAMs led to an increase in volatile solids removal from 56.2% to 77.5%, methane production rate from 0.59 to 1.00 L/L.d, methane yield from 0.26 to 0.34 L/g CODr, and biogas methane content from 59.9% to 71.6%. It suggests that bio-augmentation enhances DIET, promoting the conversion of volatile fatty acids to methane and enhancing resilience against kinetic imbalances. The enrichment of EAMs reached optimal efficacy under an electric field intensity of 2.07 V/cm with a mean exposure time of 2.53 days to the electric field in the BEAR. Bio-augmentation with externally enriched EAMs is a feasible and effective strategy to optimize anaerobic digestion processes.

Kenji Kiyohara, Takushi Sugino, Kinji Asaka

Advances in Science and Technology • 2008

In order to understand the mechanism of the bending motion of the electroactive polymer actuators from the molecular interaction, we performed Monte Carlo simulations in two length scales; the micrometer scale and the nanometer scale. In the micrometer scale picture, the bending motion of an actuator can be viewed as the inhomogeneous expansion/contraction of the three layer system. We theoretically formulated the deformation of the actuator in terms of the elastic constants and the stress exerted due to the applied voltage. For the nanometer scale, noting that the electrodes of the EAP actuators have porous structures, we modeled the anode and the cathode by the porous electrodes where the ions are confined in the space with the dimension comparable to the ion size. We found that significant osmotic stress arises in the porous electrodes when voltage is applied. The results of such multi-scale analyses are combined with the experimental results to obtain the insights into the molecular mechanism of the actuators and to give the guideline for the molecular design of the actuators.

Mirian Samblas, J. Alfredo Martínez, Fermín Milagro

Mediators of Inflammation • 2018

DNA methylation has been suggested as a regulatory mechanism behind some inflammatory processes. The physiological actions of methyl donors, such as folic acid, choline, and vitamin B 12 on inflammation-related disease have been associated with the synthesis of the universal methyl donor S-adenosyl methionine (SAM). The aim of this study was to evaluate the effects of folic acid, choline, vitamin B 12 , and a combination of all on preventing the lipopolysaccharide- (LPS-) induced inflammatory response in human THP-1 monocyte/macrophage cells. Folic acid and the mixture of methyl donors reduced interleukin 1 beta (IL1B) and tumour necrosis factor (TNF) expression as well as protein secretion by these cells. Folic acid and choline decreased C-C motif chemokine ligand 2 ( CCL2 ) mRNA levels. In addition to this, the methyl donor mixture reduced Cluster of differentiation 40 (CD40) expression, but increased serpin family E member 1 (SERPINE1) expression. All methyl donors increased methylation levels in CpGs located in IL1B , SERPINE1 , and interleukin 18 (IL18) genes. However, TNF methylation was not modified. After treatment with folic acid and the methyl donor mixture, ChIP analysis showed no change in the binding affinity of nuclear factor- κ B (NF- κ B) to IL1B and TNF promoter regions after the treatment with folic acid and the methyl donor mixture. The findings of this study suggest that folic acid might contribute to the control of chronic inflammation in inflammatory-related disease.

Boyeth Pelone, Patricia Ann Sanchez

International Journal of Built Environment and Sustainability • 2025

Amid escalating climate change and other factors, communities in vulnerable areas like Tagum City, Davao del Norte, Philippines, face increasing risks of severe flooding, threatening their safety, livelihoods, and well-being. This highlights the urgent need for comprehensive analysis of flood dynamics and community resilience within a social-ecological system framework, addressing the critical gap in local-level research to inform effective flood risk management strategies. This study employed a combined systematic literature review, Fuzzy Delphi Method, and Analytical Hierarchy Process to develop a Flood Resilience Index (FRI) and resilience map using QGIS. The findings underscore that a significant portion of Tagum City exhibits medium resilience to flooding, with an FRI of 3.221. Notably, several towns identified as medium resilient, including Bincungan (2.801), Pandapan (2.661), Busaon (2.910), and Liboganon (2.660), face heightened vulnerability due to the potential for high flood water levels, exceeding critical thresholds, with a peak level of 11 meters for a projected 5-year return period. The study highlights the interconnectedness of social-ecological components, emphasizing that overall system resilience depends on its weakest elements. To enhance resilience in flood-vulnerable areas, it is crucial to strengthen economic, institutional, and socio-cultural support systems through targeted activities, policies and programs. This research provides crucial insights into the intricate relationship between flooding and resilience, serving as a foundation for informed decision-making and proactive measures to mitigate flood risks, enhance community well-being, and advance climate action for a more resilient and sustainable Tagum City and similar environments.

Yi Wu, Claire Flemmer

International Journal of Built Environment and Sustainability • 2020

Glass curtain wall provides an attractive building envelope, but it is generally regarded as unsustainable because of the high energy needed to maintain thermal comfort. This research explores the advances in the technology of glass cladding and the complex issues associated with judging its sustainability. It assesses the technology and sustainability of glass curtain wall on a sample of thirty commercial buildings in Auckland, New Zealand. Field observations of the glass-clad buildings, coupled with surveys of the building occupants and of glass cladding professionals are used to investigate the cladding characteristics, operational performance, sustainability aspects and future trends. The majority of the sample buildings are low-rise office buildings. The occupants like the aesthetics and indoor environment quality of their glass-clad buildings. However, continuous heating, ventilation and air conditioning are needed in order to maintain thermal comfort within the buildings and this has high energy consumption. The increasing use of unitized systems with double glazing instead of stick-built systems with single glazing improves the sustainability of the cladding through less material wastage and better energy efficiency. Inclusion of photovoltaic modules in the curtain wall also improves energy efficiency but it is currently too expensive for use in New Zealand. Environmental sustainability is also improved when factors such as climate, the orientation of glazed façades, solar control, ventilation and the interior building layout are considered. Any assessment of glass curtain wall sustainability needs to consider the economic and social aspects as well as the environmental aspects such as energy use

Taniela Marli Bes, Marina Cortês Farrel, Carlos Santos et al.

medRxiv • 2022

Abstract Antimicrobial resistance has grown exponentially in the last decade and become a global health threat. The antibiotic resistance crisis has guided the scientific community to explore non-conventional interventions to target resistant bacteria. Development of new technologies, such as aptamers-based treatment and diagnosis, has shown to be promising with remarkable advantages over the past five years. This narrative review aims on what is already known regarding application of aptamer technology in enterobacteria and non-fermenters, and the prospects for future achievements. A systematic search of the English literature was performed on the 7th of December 2021 to identify papers on aptamer discovery, with a focus on gram negative isolates, published from January 01, 1993, to December 07, 2021, under the topics: (aptamer OR aptamers OR SELEX) AND (bacteria OR sepsis OR non-fermenter OR Enterobacteriaceae OR infection)). The reference lists of included articles were also searched, in addition to hand-searching of various relevant high-impact journals. Out of 2,474 articles, 30 experimental studies were recruited for review, and are chronologically described. Although the number of publications regarding development of aptamers to target these pathogenic agents has increased over the years, the recent publications are mostly around diagnostic devices manufactured using previously described aptamers. There have been less than one-third of the studies describing new and specific aptamers. From the 30 selected papers, 18 are regarding non-fermenters, seven approaching multi-species of bacteria and only five regarding a single enterobacteria. Even for the newly described aptamers, most of the published papers pertain to diagnostic aptamers and only seven focus on aptamers for therapeutics. The number of aptamers with strong and specific binding capacity are still limited. Improving the current SELEX and developing more APT remains the major hurdle for aptamer related studies.

Mireia Saladrigas-García, Mario Durán, Matilde D’Angelo et al.

Animal Microbiome • 2022

Abstract Background The establishment of the gut microbiota can be influenced by several perinatal factors, including, most importantly, the maternal microbiota. Moreover, early-life environmental variation affects gut microbial colonization and the intestinal health of offspring throughout life. The present study aimed to explore the development of piglet gut microbiota from birth to weaning in the commercial practice and also to assess how different farm environments could condition this process. Although it is possible to find in the literature other studies with similar objectives this work probably represents one of the few studies that make a systematic evaluation of such differential factors under a real scenario. To achieve this objective, we performed two trials. In a first Trial, we selected 2 farms in which we performed an intensive sampling (5 samples /animal) to characterize the gut colonization pattern during the first days of life and to identify the time window with the greatest impact. Both farms differed in their health status and the use of antimicrobials in the piglets. In a second Trial, we selected 4 additional farms with variable rearing conditions and a distinctive use of antimicrobials in the sows with a simplified sampling pattern (2 samples/animal). Faecal samples were obtained with swabs and DNA was extracted by using the PSP® Spin Stool DNA Kit and sequencing of the 16S rRNA gene (V3-V4 region) performed by Illumina MiSeq Platform. Results The present study contributes to a better understanding of microbiome development during the transition from birth to weaning in commercial conditions. Alpha diversity was strongly affected by age, with an increased richness of species through time. Beta diversity decreased after weaning, suggesting a convergent evolvement among individuals. We pinpointed the early intestinal colonizers belonging to Bacteroides, Escherichia-Shigella , Clostridium sensu stricto 1, and Fusobacterium genera. During lactation(d7-d21 of life), the higher relative abundances of Bacteroides and Lactobacillus genera were correlated with a milk-oriented microbiome. As the piglets aged and after weaning (d36 of life), increasing abundances of genera such as Prevotella , Butyricimonas , Christensenellaceae R-7 group , Dorea , Phascolarctobacterium , Rikenellaceae RC9 gut group , Subdoligranulum, and Ruminococcaceae UCG-002 were observed. These changes indicate the adaptation of the piglets to a cereal-based diet rich in oligosaccharides and starch. Our results also show that the farm can have a significant impact in such a process, evidencing the influence of different environments and rearing systems on the gut microbiota development of the young piglet. Differences between farms were more noticeable after weaning than during lactation with changes in alpha and beta biodiversity and specific taxa. The analysis of such differences suggests that piglets receiving intramuscular amoxicillin (days 2–5 of life) and being offered an acidifying rehydrating solution (Alpha farm in Trial 1) have a greater alpha diversity and more abundant Lactobacillus population. Moreover, the only farm that did not offer any rehydrating solution (Foxtrot farm in Trial 2) showed a lower alpha diversity (day 2 of life) and increased abundance of Enterobacteriaceae (both at 2 and 21 days). The use of in-feed antibiotics in the sows was also associated with structural changes in the piglets’ gut ecosystem although without changes in richness or diversity. Significant shifts could be registered in different microbial groups, particularly lower abundances of Fusobacterium in those piglets from medicated sows. Conclusions In conclusion, during the first weeks of life, the pig microbiota showed a relevant succession of microbial groups towards a more homogeneous and stable ecosystem better adapted to the solid dry feed. In this relevant early-age process, the rearing conditions, the farm environment, and particularly the antimicrobial use in piglets and mothers determine changes that could have a relevant impact on gut microbiota maturation. More research is needed to elucidate the relative impact of these farm-induced early life-long changes in the growing pig.