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Migration of styrene oligomers from food contact materials: in silico prediction of possible genotoxicity. Dear Editor, I read with considerable interest the recent paper by Beneventi and co-workers on the migration of styrene oligomers (SO) from food contact materials. Beneventi and co-workers also raised concern that the analogues identified in the QSAR models employed did not contain the cyclobutane fragment present in SD4 and further investigated six cyclobutane derivatives (SD4-1 to SD4-6 in their supplemental information - file 1). [Extracted from the article]

The design and synthesis of dansyl-appended fluorescent sequence-defined oligomers (SDOs) for the selective detection of toxic Hg2+ ions in water is reported. The system incorporates dithiocarbamate (DTC) to act as the binding unit and hydroxy group at the terminal site to improve water solubility. The sensor exhibited positive solvatochromism. This platform has the advantage of systematically increasing the number of DTC units to improve the sensitivity and in doing so, a 100-fold enhancement in sensitivity was obtained by increasing the number of DTC from one to two. A very low detection limit of 60 pM was achieved with the two DTC system and this platform has scope to improve LOD further. Moreover, visual detection and fabrication of paper strip for easy detection of Hg2+ ions are also possible. The sensor selectively binds to Hg2+ ions even in presence of competitive ions and was applied for detection of Hg2+ contamination in lake and tap water samples. Further, we successfully used our sensor for cell imaging in MCF-7 and HeLa cancer cell lines and detect Hg2+ using fluorescence microscopy. The same system was also capable of removing Hg2+ ions from water with an efficiency > 95%. [Display omitted] • Dansyl-appended sequence-defined oligomers (SDOs) for the selective detection of Hg2+ ions in water and live cells. • Number of DTC units (receptor) were increased to improve sensitivity. • Detection limit in picomolar range was achieved with the two DTC system. • Visual detection of Hg2+. • Fabrication of paper strip-based system. • Detection of Hg2+ contamination in lake and tap water samples. • Cell imaging in MCF-7 and HeLa cell lines, and detection of Hg2+ in the living cells. • Removal of Hg2+ ions from water with an efficiency > 95%. [ABSTRACT FROM AUTHOR]

The optimal design of high wear‐resistance and durability of coatings using organic–inorganic interpenetrating networks has been a long‐term goal of researchers. Although some progress has been made in the modification of waterborne polyurethanes (WPU), there are still significant challenges in fabricating more durable polyurethane‐based protective coatings from the perspective of structural design at a molecular level. Here, a sub‐nanoscaled (<1 nm) inorganic calcium phosphate oligomer (CPO) is used to carry out organic–inorganic hybrid cross‐linking in a WPU network and precisely regulate the structure of the macromolecular network at the molecular level. The herein‐produced CPO‐WPU hybrid coating shows excellent wear resistance and water resistance. Taber abrasion tests demonstrate that the CPO‐WPU coating can be capable of 15 500 turns at a load of 750 g, 2.2 times that of pure WPU coating, and the water‐resistance of CPO‐WPU coating is significantly improved compared with WPU coating due to its well‐integrated organic–inorganic network. Overall, the CPO‐WPU coating material significantly improves the mechanical strength, wear‐resistance, and water‐resistance, compared with the original WPU coating and other modified polyurethane. This hybrid coating can provide a potential application in paper‐making, textiles, and furniture due to its unique organic–inorganic network, low cost, and green process. [ABSTRACT FROM AUTHOR]

Nano-plastics have been found in snow and evidence shows that they can act as nuclei. The aerosol water-uptake ability is an important property that will determine wet deposition, a potential main route for nano-plastics to fall to the ground. In this work, we measure the hygroscopicity of three nano-plastics: low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polyvinyl chloride (PVC), and a fourth compound, cellulose, with in-situ aerosol techniques via a cloud condensation nuclei counter. Cellulose is a high-molecular weight compound and a main component of commonly used paper products. Ultrafine nano-plastic particles in the range of 20 to 200 nm are explored. Nano-plastic materials LDPE, PET, and PVC form droplets more readily than cellulose nanoparticles. The high hygroscopicity of nano-plastics indicates that the nano-plastics are either oligomers or a polymer with properties for water adsorption. Furthermore, a single parameter hygroscopicity, κ, derived from different droplet activation models (Flory Huggins Köhler and Frenkel-Halsey-Hill adsorption theory) are reported. Moreover, the molecular weights of the leached oligomers are predicted by Flory Huggins Köhler theory assuming ideal polymer mixing. The observed intrinsic hygroscopicity is size-dependent, hence the adsorption-based hygroscopicity model could be applied. Nano-plastics can be incorporated into clouds, transported globally, and may also be removed from the atmosphere via wet deposition processes. The analysis of hygroscopicity help estimating the lifetime and transport of nano-plastic particles in the atmosphere. [ABSTRACT FROM AUTHOR]

Diblock conjugated oligomers are π-conjugated molecules that contain two segments having distinct frontier orbital energies and HOMO-LUMO gap offsets. These oligomers are of fundamental interest to understand how the distinct π-conjugated segments interact and modify their excited state properties. The current paper reports a study of two series of diblock oligomers that contain oligothiophene (Tn) and 4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (TBT) segments that are coupled by either ethynyl (-C≡C-) or trans-(-C≡C-)2Pt(II)(PBu3)2 acetylide linkers. In these structures, the Tn segment is electron rich (donor), and the TBT is electron poor (acceptor). The diblock oligomers are characterized by steady-state and time-resolved spectroscopy, including UV-visible absorption, fluorescence, fluorescence lifetimes, and ultrafast transient absorption spectroscopy. Studies are compared in several solvents of different polarity and with different excitation wavelengths. The results reveal that the (-C≡C-) linked oligomers feature a delocalized excited state that takes on a charge transfer (CT) character in more polar media. In the (-C≡C-)2Pt(II)(PBu3)2-linked oligomers, there is weak coupling between the Tn and TBT segments. Consequently, short wavelength excitation selectively excites the Tn segment, which then undergoes ultrafast energy transfer (~1 ps) to afford a TBT-localized excited state. [ABSTRACT FROM AUTHOR]

The disruption of the blood–brain barrier (BBB) in Alzheimer's Disease (AD) is largely influenced by amyloid beta (Aβ). In this study, we developed a high-throughput microfluidic BBB model devoid of a physical membrane, featuring endothelial cells interacting with an extracellular matrix (ECM). This paper focuses on the impact of varying concentrations of Aβ1–42 oligomers on BBB dysfunction by treating them in the luminal. Our findings reveal a pronounced accumulation of Aβ1–42 oligomers at the BBB, resulting in the disruption of tight junctions and subsequent leakage evidenced by a barrier integrity assay. Additionally, cytotoxicity assessments indicate a concentration-dependent increase in cell death in response to Aβ1–42 oligomers (LC50 ~ 1 µM). This study underscores the utility of our membrane-free vascular chip in elucidating the dysfunction induced by Aβ with respect to the BBB. [ABSTRACT FROM AUTHOR]

The paper focuses on the correction of Illumina WGS sequencing reads. We provide an extensive evaluation of the existing correctors. To this end, we measure an impact of the correction on variant calling (VC) as well as de novo assembly. It shows, that in selected cases read correction improves the VC results quality. We also examine the algorithms behaviour in a processing of Illumina NovaSeq reads, with different reads quality characteristics than in older sequencers. We show that most of the algorithms are ready to cope with such reads. Finally, we introduce a new version of RECKONER, our read corrector, by optimizing it and equipping with a new correction strategy. Currently, RECKONER allows to correct high-coverage human reads in less than 2.5 h, is able to cope with two types of reads errors: indels and substitutions, and utilizes a new, based on a two lengths of oligomers, correction verification technique. [ABSTRACT FROM AUTHOR]

Synapse loss is the principal cause of cognitive decline in Alzheimer's disease (AD) and related disorders (ADRD). Synapse development depends on the intricate dynamics of the neuronal cytoskeleton. Cofilin, the major protein regulating actin dynamics, can be sequestered into cofilactin rods, intra-neurite bundles of cofilin-saturated actin filaments that can disrupt vesicular trafficking and cause synaptic loss. Rods are a brain pathology in human AD and mouse models of AD and ADRD. Eliminating rods is the focus of this paper. One pathway for rod formation is triggered in ~20% of rodent hippocampal neurons by disease-related factors (e.g., soluble oligomers of Amyloid-β (Aβ)) and requires cellular prion protein (PrPC), active NADPH oxidase (NOX), and cytokine/chemokine receptors (CCRs). FDA-approved antagonists of CXCR4 and CCR5 inhibit Aβ-induced rods in both rodent and human neurons with effective concentrations for 50% rod reduction (EC50) of 1–10 nM. Remarkably, two D-amino acid receptor-active peptides (RAP-103 and RAP-310) inhibit Aβ-induced rods with an EC50 of ~1 pM in mouse neurons and ~0.1 pM in human neurons. These peptides are analogs of D-Ala-Peptide T-Amide (DAPTA) and share a pentapeptide sequence (TTNYT) antagonistic to several CCR-dependent responses. RAP-103 does not inhibit neuritogenesis or outgrowth even at 1 µM, >106-fold above its EC50. N-terminal methylation, or D-Thr to D-Ser substitution, decreases the rod-inhibiting potency of RAP-103 by 103-fold, suggesting high target specificity. Neither RAP peptide inhibits neuronal rod formation induced by excitotoxic glutamate, but both inhibit rods induced in human neurons by several PrPC/NOX pathway activators (Aβ, HIV-gp120 protein, and IL-6). Significantly, RAP-103 completely protects against Aβ-induced loss of mature and developing synapses and, at 0.1 nM, reverses rods in both rodent and human neurons (T½ ~ 3 h) even in the continuous presence of Aβ. Thus, this orally available, brain-permeable peptide should be highly effective in reducing rod pathology in multifactorial neurological diseases with mixed proteinopathies acting through PrPC/NOX. [ABSTRACT FROM AUTHOR]

The assembly of the β-amyloid peptide (Aβ) to form oligomers and fibrils is closely associated with the pathogenesis and progression of Alzheimer's disease. Aβ is a shape-shifting peptide capable of adopting many conformations and folds within the multitude of oligomers and fibrils the peptide forms. These properties have precluded detailed structural elucidation and biological characterization of homogeneous, well-defined Aβ oligomers. In this paper, we compare the structural, biophysical, and biological characteristics of two different covalently stabilized isomorphic trimers derived from the central and C-terminal regions Aβ. X-ray crystallography reveals the structures of the trimers and shows that each trimer forms a ball-shaped dodecamer. Solution-phase and cell-based studies demonstrate that the two trimers exhibit markedly different assembly and biological properties. One trimer forms small soluble oligomers that enter cells through endocytosis and activate capase-3/7-mediated apoptosis, while the other trimer forms large insoluble aggregates that accumulate on the outer plasma membrane and elicit cellular toxicity through an apoptosis-independent mechanism. The two trimers also exhibit different effects on the aggregation, toxicity, and cellular interaction of full-length Aβ, with one trimer showing a greater propensity to interact with Aβ than the other. The studies described in this paper indicate that the two trimers share structural, biophysical, and biological characteristics with oligomers of full-length Aβ. The varying structural, assembly, and biological characteristics of the two trimers provide a working model for how different Aβ trimers can assemble and lead to different biological effects, which may help shed light on the differences among Aβ oligomers. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of NIPU by using cardanol as starting material. A cardanol formaldehyde oligomer was first prepared through the reaction of cardanol and formaldehyde, catalyzed by citric acid. The resulting oligomer was then subjected to epoxidation with m-chloroperbenzoic acid to obtain an epoxide compound, which was subsequently used to fix carbon dioxide (CO2) and form a cyclic carbonate. Using this cyclic carbonate, along with an amine, cardanol-based isocyanate polyurethane (NIPU) was prepared. Different characterization methods, such as Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and thermogravimetric analysis (TGA), were used to confirm the synthesis of the four intermediate products and NIPU in the reaction process. This study highlights the promise of bio-based NIPU as a sustainable alternative in a number of applications while offering insightful information on the synthesis and characterization of the material. [ABSTRACT FROM AUTHOR]

The process of amyloid aggregation is quite complex and poorly studied. In this paper, summarizing the previously obtained results on the aggregation of the multidomain smooth muscle protein titin, we tried to complement the idea of its amyloid aggregation by presenting a new, in our opinion, possible mechanism. The main conclusion is that the ability of titin to form amorphous aggregates seems to be the only possible means of aggregation of this protein. Apparently, only individual sections of the molecules, and not the entire protein, are involved in the formation of the amyloid structure in amorphous aggregates of smooth muscle titin. This feature distinguishes titin from other amyloid or amyloid-like proteins due to the large size of the molecule. The possible energy landscape underlying the formation of amyloid aggregates of titin is discussed. [ABSTRACT FROM AUTHOR]

Among the bases of DNA, guanine is the most easily oxidized. Imidazolone (Iz) is a guanine oxidative damage, and we sought to generate Iz-containing oligomers. In this paper, we describe the methods and conditions to increase the yield of Iz by employing photooxidation reactions using light-emitting diodes (LEDs) with emission wavelengths of 365 nm and 450 nm. For photooxidation performed with the 450 nm LED source at light intensities of 2.75–275 mW/cm2, peak yields of Iz were 35% at light intensities of 27.5 and 68.8 mW/cm2. For reactions performed with the 365 nm LED source at light intensities of 5.12–512 mW/cm2, the peak yield of Iz was 34% at a light intensity of 51.2 mW/cm2. By varying the irradiation time, the maximum yield of Iz (34–35%) was obtained with irradiation times of 5–20 min using the 450 nm LED source at an intensity of 13.8 mW/cm2. Using the 365 nm LED source at an intensity of 25.6 mW/cm2, the maximum Iz yield obtained was 31% at irradiation times of 2–5 min. Thus, we obtained conditions that can provide an Iz yield of up to 35%. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to investigate the effects on material performance in the epoxy acrylate resin system owing to the existence of the different ring of the cyclic methacrylate. In this paper, cyclic methacrylate as diluents was added into epoxy acrylate (EA) resin by ultraviolet (UV)-cured polymerization to investigate the effects on material performance owing to the existence of the different rings. Design/methodology/approach: EA and 1-adamantyl methacrylate were synthesized by traditional methods according to previous papers, respectively. After adding different cyclic methacrylate as diluents to the EA oligomers, the system was exposed to the UV-light for polymerization. Findings: The hydrophobic properties of the cured materials were increased slightly because of the alkyl groups from the methacrylate. The thermal stabilities and mechanical properties of the resins were enhanced by the cyclic diluents with the hard segments. Meanwhile, the crosslink density of the polymer decreased with the bulky group like adamantly owing to its huge structure. Research limitations/implications: The cyclic methacrylates were introduced into EA oligomers for decreasing the viscosity and increasing the materials performances, which could be recognized as new diluents applied in UV-cued polymerization. Originality/value: The results of this study will be conducive to fabricate EA resins possessed with high thermal stabilities and mechanical properties by convenient UV-cured polymerization. [ABSTRACT FROM AUTHOR]

The microtubule associated protein, tau, is implicated in a multitude of neurodegenerative disorders that are collectively termed as tauopathies. These disorders are characterized by the presence of tau aggregates within the brain of afflicted individuals. Mutations within the MAPT gene that encodes the tau protein form the genetic backdrop for familial forms of tauopathies, such as frontotemporal dementia (FTD), but the molecular consequences of such alterations and their pathological effects are unclear. We sought to investigate the conformational properties of the aggregates of three tau mutants: A152T, P301L, and R406W, all implicated within FTD, and compare them to those of the native form (WT‐Tau 2N4R). Our immunochemical analysis reveals that mutants and WT tau oligomers exhibit similar affinity for conformation‐specific antibodies but have distinct morphology and secondary structure. Additionally, these oligomers possess different dye‐binding properties and varying sensitivity to proteolytic processing. These results point to conformational variety among them. We then tested the ability of the mutant oligomers to cross‐seed the aggregation of WT tau monomer. Using similar array of experiments, we found that cross‐seeding with mutant aggregates leads to the formation of conformationally unique WT oligomers. The results discussed in this paper provide a novel perspective on the structural properties of oligomeric forms of WT tau 2N4R and its mutant, along with shedding some light on their cross‐seeding behavior. [ABSTRACT FROM AUTHOR]

C-Glycosyl amino acids are a group of C-glycosides in which a carbohydrate molecule is attached to the side chain or backbone of the amino acid via a C–C bond. Despite the numerous methods that have been developed for their synthesis, the C-glycosyl α-amino acids and their oligomers are relatively unexplored. In this work, we presented a protocol for the synthesis of oligomers containing alternating C-glycosyl α-amino acids and proteinogenic α-amino acids. The methodology is based on the modification of α-acyloxyamides obtained from the Passerini reaction using α- D -galactopyranose- and α- L -sorbofuranose-derived aldehydes as C-glycosyl donors. The protocol enabled the synthesis of homo- and heterochiral tetramers, and homo- and heterovalent tetramers in very good yields. [ABSTRACT FROM AUTHOR]

In this paper, fully bio-based branched unsaturated polyester (BUPE) oligomers were synthesized by one-step solvent-free polycondensation using itaconic acid, isosorbide and glycerol as feedstocks. The branched structure was confirmed by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy (1H NMR). The effect of the branched structure on the properties of BUPE UV curing coatings was investigated. The results showed that the introduction of a glycerol branched structure was favorable for UV curing. The BUPE UV curing coatings based on the glycerol branched structure showed higher gel content and crosslink density, which enhanced the hardness, solvent resistance and mechanical properties of the coatings. In addition, the BUPE UV curing coatings possessed extremely low surface roughness, excellent heat resistance and light transmission properties. [ABSTRACT FROM AUTHOR]

Solid surfaces have been shown to affect the aggregation and assembly of many biomolecular systems. One important example is the formation of protein fibrils, which can occur on a range of biological and synthetic surfaces. The rate of fibrillation depends on both the protein structure and the surface chemistry, with the different molecular and oligomer structures adopted by proteins on surfaces likely to be crucial. In this paper, the aggregation of the model amyloidogenic peptide, A β (16–22), corresponding to a hydrophobic segment of the amyloid beta protein on a gold surface is studied using molecular dynamics simulation. Previous simulations of this peptide on gold surfaces have shown that it adopts conformations on surfaces that are quite different from those in bulk solution. These simulations show that this then leads to significant differences in the oligomer structures formed in solution and on gold surfaces. In particular, oligomers formed on the surface are low in beta-strands so are unlike the structures formed in bulk solution. When oligomers formed in solution adsorb onto gold surfaces they can then restructure themselves. This can then help explain the inhibition of A β (16–22) fibrillation by gold surfaces and nanoparticles seen experimentally. [ABSTRACT FROM AUTHOR]

A series of triarylamines was synthesised and screened for their suitability as catholytes in redox flow batteries using cyclic voltammetry (CV). Tris(4‐aminophenyl)amine was found to be the strongest candidate. Solubility and initial electrochemical performance were promising; however, polymerisation was observed during electrochemical cycling leading to rapid capacity fade prescribed to a loss of accessible active material and the limitation of ion transport processes within the cell. A mixed electrolyte system of H3PO4 and HCl was found to inhibit polymerisation producing oligomers that consumed less active material reducing rates of degradation in the redox flow battery. Under these conditions Coulombic efficiency improved by over 4 %, the maximum number of cycles more than quadrupled and an additional theoretical capacity of 20 % was accessed. This paper is, to our knowledge, the first example of triarylamines as catholytes in all‐aqueous redox flow batteries and emphasises the impact supporting electrolytes can have on electrochemical performance. [ABSTRACT FROM AUTHOR]

Even though thermofluorochromic materials are eternal candidates for their use in multiple applications, they are still limited as they require complex synthetic strategies to accomplish tunable optical properties and/or provide optical changes only over a very wide temperature range. By taking advantage of the high sensitivity of the optical properties of conjugated polymers and oligomers to the external environment, herein phase change material (PCM)‐based thermofluorochromic mixtures are created, where the solid‐to‐liquid transition of the PCM host triggers a sharp fluorescence color change of the dispersed polymers/oligomers. Fluorophore conjugation length, concentration, and PCM nature can be used to vary the spectral properties of the resulting materials along the visible region, covering a large part of the CIE 1931 color space. For the preparation of functional devices, this behavior can be directly transferred to the solid state by soaking or printing cellulose papers with the obtained thermofluorochromic mixtures as well as by structuring them into solid lipid particles that can be dispersed within polymer matrices. The resulting materials show very promising features as thermal sensors and anticounterfeiting labels. [ABSTRACT FROM AUTHOR]

Single-pass membrane proteins, which constitute up to 50% of all transmembrane proteins, are typically active in significant conformational changes, such as a dimer or other oligomers, which is essential for understanding the function of transmembrane proteins. Finding the key motifs of oligomers through experimental observation is a routine method used in the field to infer the potential conformations of other members of the transmembrane protein family. However, approaches based on experimental observation need to consume a lot of time and manpower costs; moreover, they are hard to reveal the potential motifs. A proposed approach is to build an accurate and efficient transmembrane protein oligomer prediction model to screen the key motifs. In this paper, an attention-based Global-Local structure LSTM model named GLTM is proposed to predict dimers and screen potential dimer motifs. Different from traditional motifs screening based on highly conserved sequence search frame, a self-attention mechanism has been employed in GLTM to locate the highest dimerization score of subsequence fragments and has been proven to locate most known dimer motifs well. The proposed GLTM can reach 97.5% accuracy on the benchmark dataset collected from Membranome2.0. The three characteristics of GLTM can be summarized as follows: First, the original sequence fragment was converted to a set of subsequences which having the similar length of known motifs, and this additional step can greatly enhance the capability of capturing motif pattern; Second, to solve the problem of sample imbalance, a novel data enhancement approach combining improved one-hot encoding with random subsequence windows has been proposed to improve the generalization capability of GLTM; Third, position penalization has been taken into account, which makes a self-attention mechanism focused on special TM fragments. The experimental results in this paper fully demonstrated that the proposed GLTM has a broad application perspective on the location of potential oligomer motifs, and is helpful for preliminary and rapid research on the conformational change of mutants. [ABSTRACT FROM AUTHOR]

Bottom-up synthesis of siloxane-based nanoporous materials from siloxane oligomers is promising for constructing well-defined structures at a molecular level. Herein, we report the synthesis of nanoporous materials consisting of cage-type siloxanes through the nonhydrolytic siloxane bond formation reaction. Cage siloxanes with double-n-ring geometries (n = 4 or 6) modified with dimethylsilyl and dimethylethoxysilyl groups are synthesized and directly cross-linked using a B(C6F5)3 catalyst, resulting in the formation of porous networks composed of alternating cage siloxane nodes and tetramethyldisiloxane (-SiMe2OSiMe2-) linkers. Compared with conventional hydrolysis and polycondensation reactions of alkoxysilyl-modified cage siloxanes under acid conditions, the non-hydrolytic condensation reaction was found favorable for the formation of porous siloxane networks without unwanted cleavage of the siloxane bonds. [ABSTRACT FROM AUTHOR]

Bis(diimino)metal complex nanosheets composed of metal ions and hexaaminobenzene ligands (MHABs) are fascinating two-dimensional materials which have been gaining significant attention as electrode materials and electrocatalysts owing to their electrical conductivities, redox properties, and porous structures obtained by the π-conjugated system and regular metal complex arrangement. Although electrochemical oxidation enables the simple and direct formation of MHABs on electrodes within a couple of minutes only, the obtained MHABs are relatively rough and of low crystallinity. This study investigated the effects of the applied potential during the synthesis, the type of base, and the concentrations of bases and building blocks on the synthesis of NiHAB nanosheets. Optical microscopy (OM), atomic force microscopy (AFM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and grazing-incidence X-ray scattering (GIXS) results revealed that a low oxidation potential, high concentration of the ammonia solution, and low concentration of the building blocks in the reaction solution provided a nanometre-thick NiHAB layer. Under the optimal reaction conditions, NiHAB nanosheets were successfully synthesized in a face-on orientation manner on gold electrodes using electrochemical oxidation methods. Furthermore, the anisotropic electrochemical synthesis of CuHAB was achieved under the optimised conditions. The mechanism of the MHAB growth process with an anisotropic orientation and nanometre thickness was proposed and attributed to the flat adsorption of p-conjugated oligomers composed of bis(diamino)metal moieties in a solution onto an electrode surface and the electrochemical oxidation and deprotonation of the adsorbates on the electrode. [ABSTRACT FROM AUTHOR]

Protein oligomers are important intermediates in the formation of amyloid fibrils. In amyloidosis, for example, Alzheimer's disease, oligomers can have a toxic effect on cells. This paper describes the distinctive features of oligomerization of multidomain muscle proteins, smooth muscle titin, and myosin-binding protein C (C-protein) of skeletal muscles consisting of FnIII-like and IgC2-like domains and capable of forming amyloid amorphous aggregates in vitro. Under conditions of low ionic strength (below physiological values), the C-protein formed stable oligomers that were not involved in further aggregation. Smooth muscle titin formed oligomers under conditions of high ionic strength (μ ~ 0.6), which were precursors of amyloid amorphous aggregates of this protein.The results we obtained expand the understanding of the process of protein aggregation. [ABSTRACT FROM AUTHOR]

Recently there have been significant advances in the viscosification of CO2 using a low concentration of oligomers. The new engineered molecules do not adsorb onto rock. This paper studies the effects of different CO2-enhanced viscosity levels in subsurface aquifers and reservoirs. The study was conducted using numerical modeling and simulation tools in homogeneous, heterogenous, fractured, and unfractured media. The viscosity enhancement of CO2 varied from 2- to 20-fold. The simulations included homogeneous, layered, and fractured domains in 2D and in 3D for improved oil recovery. The results showed that in unfractured, homogenous, and layered media, a 10-fold viscosity increase leads to significant increases in oil recovery. In a fractured medium with a highly connected fracture network, a 20-fold viscosity enhancement may have a considerable effect in delaying breakthrough and improving oil recovery. Simulations were performed in a compositional three-phase flow based on higher-order discretization. The algorithm included Fickian diffusion, which may add to oil recovery performance when there is a sufficient surface area between the CO2-rich phase and the oil phase. In CO2 sequestration, an increase in the viscosity of CO2 and consequent mobility control promotes CO2 dissolution in the aqueous phase. Due to the increase in the density of the aqueous phase from CO2 dissolution, the CO2 is carried away from the cap rock to the bottom of the formation. This work is of particular importance in improved oil recovery and in safe CO2 sequestration due to solubility trapping and mitigation of pressure increase. The higher-order numerical scheme used in this simulation guarantees a level of accuracy not obtained in traditional simulators. [ABSTRACT FROM AUTHOR]

In this paper, a series of novel carbazole-based polysiloxane oligomers: P(CzVinyl11Siloxane2), P(CzVinyl21Siloxane2), and P(CzVinyl11Siloxane3) with high refractive index (RI) containing the linear and/ or branched structures with vinyl and carbazole reactive moieties have been presented to the literature for optoelectronic applications. The polysiloxane oligomers were synthesized by an acid-catalyzed sol–gel condensation reaction of alkoxysilane monomers (carbazole-dimethoxysilane (Cz-2SiOCH3) and vinyl-(di- or tri-methoxy)silanes (VMDMS or VTMS)) in the presence of trimethylmethoxysilane (SiMe) after a photoinitiated thiol-ene reaction was performed to obtain the compound Cz-2SiOCH3. The structural confirmations were made using FT-IR, 1H NMR, and 13C NMR spectroscopies. In addition, a 29Si NMR study was performed to elucidate the nature of the siloxane structure of P(CzVinyl11Siloxane2). The refractive indices of the polysiloxane oligomers were between 1.6028 and 1.5923 as high values by varying the linear or branched structures. DSC analyzes revealed that the glass transition temperatures of P(CzVinyl11Siloxane2), P(CzVinyl21Siloxane2), and P(CzVinyl11Siloxane3) were -11 °C, -5 °C and -39 °C, respectively. Then, the polysiloxane oligomers were photopolymerized and their structural changes were observed by spectroscopic techniques. The photopolymerized polysiloxane oligomers with maintained and/ or enhanced refractive index values (between 1.6132 and 1.5719) showed very good transparency between 86.11% and 81.33% at 600 nm by the spin coating films. The novel carbazole-based polysiloxane oligomers would be useful chemical products or intermediates for the development of optical materials applied in optoelectronic devices. [ABSTRACT FROM AUTHOR]

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In this paper, we designed and synthesised three Schiff base mesogenic units X-YP and six Y-shaped liquid crystal oligomers X-AYP and X-BYP (×= -CH3O, -CH3, -Cl). Molecular structures of the prepared compounds were confirmed via FT-IR, 1H NMR and elemental analysis. The mesomorphic properties were investigated by differential scanning calorimetry (DSC) and polarised light microscopy (POM). The photochemical properties of Y-shaped liquid crystal oligomers were preliminarily studied by UV-Vis spectrum. The results indicated that X-YP containing OCH3 and Cl substituents exhibited mesophase, while X-YP with CH3 substituent was non-mesogenic. The synthesized Y-shaped liquid crystals X-AYP and X-BYP both had liquid crystal properties and exhibited nematic phase during heating and cooling, which belonged to thermotropic enantiotropic nematic liquid crystals. The polarity of the terminal groups and the number of mesogenic units had a significant effect on the mesophase behaviour of Y-shaped liquid crystals. The absorption intensities of X-AYP and X-BYP in the UV spectra were affected by the terminal substituents. [ABSTRACT FROM AUTHOR]

The paper presents a fascinating photo physics of the light emitting polymer (LEP), poly2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) when diluted by the solid poly methylmethacrylate (PMMA) environment. The neat MDMO-PPV exhibiting the single peak absorption at 496.6 nm and emission at 589 nm (of 0–0 transition) displays the blue and red shifted bimodal absorption and emissions simultaneously in the presence of inert PMMA matrix. Blue phase peaks are dominant for low dopant concentrations whereas the red phase peaks are dominant at higher concentrations. A switching from blue phase to red phase is due to transition from collapsed chain conformations to coupled or aggregated conformations of conjugated chains of MDMO-PPV. At low doping level, the intra-chain excitonic coupling between the transition dipoles (TDMs) of MDMO-PPV are disrupted by the PMMA matrix, whereas the intra-chain excitonic coupling is pronounced at higher doping levels in accordance with Kasha's model of aggregation. The emissions around 525 and 530 nm correspond to MDMO-PPV oligomer precursors and that around 580 to 605 nm are due to J aggregated conjugated chains. The activation energy calculations from Broido's, Horwitz-Metzer and Van –Kravelin methods are in good agreement, elucidating the correctness and consistency of the techniques used. Increase in the thermal stability of the samples with the increased doping level is affirmed by increase in activation energy from about 105 to 155 kJ/ mole. The XRD studies confirm the blue phase induced disorder and supported by the occurrence of the FTIR resonant peaks related to vinyl ring wagging and C = C stretching modes. Enhanced dc and conductivity increase in dielectric constant, the photo physics related parameters like energy gap, Urbach energy and Stokes shifts are reported. Highly correlated wavelength shifts and intensities of emission for both the exciting wavelengths 340 nm and 450 nm along with the unprecedented tuning of emission over wide range of the visible region with the most simple and the economic solution cast method are the novelty of this work. This invention can boost the technological aspects of plastic electronic display devices, like LED, LASER, solar cell and EM shielding. [ABSTRACT FROM AUTHOR]

In this paper we propose a numerical method to localize many‐electron excited states. To characterize the electronic structure of the electronic excited states of a system, quantum chemistry methods typically yield a delocalized description of the excitations. Some a priori localization methods have been developed to provide an intuitive local picture of the excited states. They typically require a good strategy to separate the system of interest from its environment, or a set of a priori localized orbitals, that may reduce their computational accuracy. Here, we introduce an a posteriori method to localize delocalized many‐body excited states directly obtained from quantum chemistry calculations. A localization metric for the excited states is defined from their representation as electron–hole pairs, which is encoded in the transition density matrix. This novel a posteriori strategy thus allows to localize excitons within a volume around selected fragments of a complex molecular system without tempering with its quantum chemical treatment. The method is tested on π‐stacked oligomers of phenanthrenes and pyrenes. It is found to efficiently localize and separate the excitons according to their character while preserving the information about delocalized many‐body states at a low computational cost. [ABSTRACT FROM AUTHOR]

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Incorporating hydrolytically sensitive functional groups into polymer backbones provides a feasible strategy to trigger their degradation to the starting monomers, thus enabling chemical recycling of the material. Here, we present two series of copolyesters in which a biobased spirocyclic ketal-functional diester monomer was incorporated into poly(butylene 2,5-furandicarboxylate) (PBLF) and poly(hexamethylene 2,5-furandicarboxylate) (PHLF), respectively. A two-step melt polycondensation resulted in copolyesters with moderate to high molecular weights, as confirmed by intrinsic viscosity and size exclusion chromatography data. Thermogravimetric analysis showed a thermal stability up to 275 °C, and increasing char yields upon incorporation of the spirocyclic monomer. The crystallinity and melting points of the copolyesters decreased with an increasing content of the spirocyclic ketal units in the backbone. Copolyesters containing up to 15% of the spiro-ketal units were semicrystalline, while those containing 20 and 50% spiro-ketal units were completely amorphous. The hydrolytic degradation of copolyesters from the PHLF series was investigated using 3–12 M aq. HCl, and were found to degrade faster than the corresponding homopolyesters. Acid-catalyzed cleavage of the randomly distributed spiro ketal units promoted the rapid fragmentation of the polymer chain into small oligomers, which were subsequently hydrolyzed to the original chemical building blocks. The ketone-terminated telechelic oligomers obtained after the degradation of spirocyclic ketal units were also investigated in a direct polymerization with pentaerythritol. The initial results implied that the oligomers can be re-polymerized into the original polymer. Hence, this work demonstrated a feasible pathway towards chemically recyclable 2,5-furandicarboxylate polyesters with a tuneable degree of crystallinity. [ABSTRACT FROM AUTHOR]

Amyloidosis is a condition involving a disparate group of pathologies characterized by the extracellular deposition of insoluble fibrils composed of broken-down proteins. These proteins can accumulate locally, causing peculiar symptoms, or in a widespread way, involving many organs and. causing severe systemic failure. The damage that is created is related not only to the accumulation of. amyloid fibrils but above all to the precursor oligomers of the fibrils that manage to enter the cell in a very particular way. This article analyzes the current state of research related to the entry of these oligomers into the cell membrane and the theories related to their toxicity. The paper proposed here not only aims to review the contents in the literature but also proposes a new vision of amyloid toxicity. that could occur in a multiphase process catalyzed by the cell membrane itself. In this process, the denaturation of the lipid bilayer is followed by the stabilization of a pore through energetically favorable self-assembly processes which are achieved through particular oligomeric structures. [ABSTRACT FROM AUTHOR]

The popularity and rapid spread of new psychoactive substances is why there is an urgent need for their fast monitoring in saliva in the field with electrodes modified with a selective receptor. Oligomers of electrochemically oxidized 3-aminobenzoic acid that are deposited on the surface of a graphite screen-printed electrode (o-3ABA/G/SPE) is proposed as a selector for the analyte of forensic interest. The oligomeric structure and existence of the zwitterionic form of o-3ABA on the G/SPE surface was confirmed using scanning electron microscopy, Raman spectroscopy and cyclic voltammetry techniques. The equilibrium adsorption constants between o-3ABA and 2-aminoindane (primary amine: Kads(2-AI) = 5.31 × 104) and selected synthetic cathinones (secondary amine: Kads(butylone) = 6.12 × 105, tertiary amines: Kads(MDPV) = 3.41 × 104 and Kads(naphyrone) = 1.01 × 104) were estimated using the electrochemical impedance spectroscopy (EIS) technique. The EIS technique was applied for determining a 1.0 μM concentration of 2-AI (RSD 3.5–4.0%) and butylone (RSD 4.9–6.4%) in the model and oral fluid samples. [ABSTRACT FROM AUTHOR]

A series of new gold nanocomposite materials, GNC_LCx (x = 6–11), was obtained from a series of non-linear liquid crystal oligomers, LCx (x = 6–11), with a gold nanocluster (GNC) possessing a formulation of [Au25(SC12H25)18]TOA, which is represented as Au25. The oligomers consist of a central disulphide (S–S) linkage wherein the length of the inner alkyl spacer n1 varied from 6 to 11, whilst the outer alkyl length n2 was fixed at 6. The synthesis of Au25 was verified using UV-vis and TEM, whereas the properties of Au25, LCx, and GNC_LCx were validated using UV-vis, PL, DLS, and TEM. However, the fundamental results of GNC_LCX suggest the possibility of core alteration, indicating that the GNC in GNC_LCx may no longer be the same Au25. The occurrence of some kind of complexation or more than one intermolecular interaction (other than hydrophobic interaction) is proposed that might contribute to the exisiting outcome. The primary findings implied that the synthesis of the nanocomposites was successful and the enhancement of the thermal stability of the transition temperatures of crystal–isotropic (TCr–I) and isotropic–nematic (TI–N) transitions along with the photoluminescence property were observed. [ABSTRACT FROM AUTHOR]

Protein self-assembly into fibrils and oligomers plays a key role in the etiology of degenerative diseases. Several pathways for this self-assembly process have been described and shown to result in different types and ratios of final assemblies, therewith defining the effective physiological response. Known factors that influence assembly pathways are chemical conditions and the presence or lack of agitation. However, in natural and industrial systems, proteins are exposed to a sequence of different and often complex mass transfers. In this paper, we compare the effect of two fundamentally different mass transfer processes on the fibrilization process. Aggregation-prone solutions of hen egg white lysozyme were subjected to predominantly non-advective mass transfer by employing centrifugation and to advective mass transport represented by orbital shaking. In both cases, fibrilization was triggered, while in quiescent only oligomers were formed. The fibrils obtained by shaking compared to fibrils obtained through centrifugation were shorter, thicker, and more rigid. They had rod-like protofibrils as building blocks and a significantly higher β-sheet content was observed. In contrast, fibrils from centrifugation were more flexible and braided. They consisted of intertwined filaments and had low β-sheet content at the expense of random coil. To the best of our knowledge, this is the first evidence of a fibrilization pathway selectivity, with the fibrilization route determined by the mass transfer and mixing configuration (shaking versus centrifugation). This selectivity can be potentially employed for directed protein fibrilization. [ABSTRACT FROM AUTHOR]

The underlying trend of colloidal synthesis has focused on extending the structure and composition complexity of colloidal particles. Hollow and yolk–shell particles are successful examples that have potential applications in frontier fields. In this paper, a facile and controllable etching method based on the molecular exchange of the dynamic imine bond to generate cavities in polymer particles is developed. Starting from boronate ester polymer particles and inorganic@boronate core–shell particles with the imine bonds incorporated in the polymer networks, the etching method easily affords hollow and yolk–shell particles with tunable shell thicknesses. The molecular exchange dynamics analysis indicates that guest amine molecules cause the reconstruction of imine bonds and the leakage of molecular and oligomer fragments, resulting in the formation of the hollow structure. This molecular exchange‐based etching method may be of interest in the construction of polymer architectures with increased composition and structure complexities. [ABSTRACT FROM AUTHOR]

Sulfonated phenol–formaldehyde (SPF) resin used as a cross-linker for petroleum reservoir conformance control was synthesized under alkaline conditions. The reaction process of SPF resin was evaluated by measuring the solution's viscosity with respect to phenol–formaldehyde (PF) resin. The molecular structure of SPF resin was characterized by both FTIR and HPLC–MS/MS. The influence of the formaldehyde/phenol molar ratio (F/P) and the sodium formaldehyde sulfoxylate/phenol molar ratio (S/P) on the properties of SPF were analyzed in terms of the storage time, coagulation value, molecular size, and zeta potential. The results indicate that the presence of formaldehyde sodium bisulfite could slow down condensation reaction. Phenol rings were connected by methylene bridges in the position of o–p, and sulfonated SPF resin molecules all had one sulfonate group on the oligomer structure. The storage time decreased from 87 to 6 days, and the zeta potential decreased from −3.02 to −7.70 mV with the increase in F/P (1.2–2.0). Meanwhile, the sedimentation value and the diameter increased from 3.291 × 104 to 5.045 × 104 mg/L and from 2.7 to 5.3 nm, respectively. Sulfonation could significantly increase the storage time and dispersion stability. With the increase in S/P (0.1–0.35), the storage time increased from 15 to 86 days, the sedimentation value increased from 1.927 × 104 to 5.269 × 104 mg/L, and the diameter decreased from 6.3 to 3.0 nm. This paper can present new ideas for improving the storage stability and salt tolerance of phenol–formaldehyde resin and further improving the range of its applications, which has essential reference significance. [ABSTRACT FROM AUTHOR]

This paper presents an investigation of the temperature dependence of the oligomeric state of the horseradish peroxidase (HRP) enzyme on the temperature of its solution, and on the solution storage time, at the single-molecule level. Atomic force microscopy has been employed to determine how the temperature and the storage time of the HRP solution influence its aggregation upon direct adsorption of the enzyme from the solution onto bare mica substrates. In parallel, spectrophotometric measurements have been performed in order to estimate whether the HRP enzymatic activity changes over time upon the storage of the enzyme solution. The temperature dependence of the HRP oligomeric state has been studied within a broad (15–40 °C) temperature range. It has been demonstrated that the storage of the HRP solution for 14 days does not have any considerable effect on the oligomeric state of the enzyme, neither does it affect its activity. At longer storage times, AFM has allowed us to reveal a tendency of HRP to oligomerization during the storage of its buffered solution, while the enzymatic activity remains virtually unchanged even after a 1-month-long storage. By AFM, it has been revealed that after the incubation of a mica substrate in the HRP solution at various temperatures, the content of the mica-adsorbed oligomers increases insignificantly owing to a high-temperature stability of the enzyme. [ABSTRACT FROM AUTHOR]

Aldimine derivatives chromophores grafted on polyacetylene oligomers were first designed to investigate the nonlinear optical (NLO) response of the resulting materials using CAMB3LYP method. The effects of different factors such as the chain length separating the substitutions as well as the configurations and the orientations of these latter, were examined and discussed. In a second part of this paper, NLO responses, in particular the static hyperpolarizabilities of polyvinyl oligomers substituted by aldimine chromophores via carboxylic groups and by pyrrolidone groups were calculated for different configurations. The stability and the hydrogen bonding in each oligomer were also discussed. [ABSTRACT FROM AUTHOR]

The conventional fractionation of lignocellulose into cellulose, hemicellulose, and lignin was generally carried out at high temperatures and under highly acidic conditions owing to the rigid matrix of lignocellulose and crystallinity of cellulose, causing the degradation of carbohydrates and condensation of lignin, thus hindering their value-added utilization. In this study, a stepwise fractionation method was proposed in which microwave-assisted fractionation of hemicellulose under mild conditions contributed to 81.9% of xylose yield; then, the cellulose part solid was rapidly dissolved in LiBr molten salt hydrate (LiBr-MSH) solution, followed by a filtration process to isolate lignin solid. It was found that the removal of hemicellulose provided more pores for the next dissolution of cellulose, and LiBr-MSH caused the cleavage of the hydrogen bonds of cellulose. Consequently, the cellulose part solid was rapidly dissolved in LiBr-MSH. The results showed that under the optimal fractionation conditions, 78.0% yield of glucan oligomers and 89.7% purity of noncondensed lignin were obtained from cellulose fractionation and filtration, respectively. A high β-O-4 bond content close to 87.3% of the theoretical maximum yield was detected in the obtained lignin, indicating that most β-O-4 bond structure of lignin was well preserved. Additionally, the isolated lignin can be selectively depolymerized into aromatic monomers with a high yield of 20.4%, which is 74.2% of the theoretical maximum yield. [ABSTRACT FROM AUTHOR]

Parahydrogen hyperpolarization has evolved into a versatile tool in NMR, allowing substantial sensitivity enhancements in analysis of biological samples. Herein we show how its application scope can be extended from small metabolites to underivatized oligopeptides in solution. Based on a homologous series of alanine oligomers, we report on an experimental and DFT study on the structure of the oligopeptide and hyperpolarization catalyst complexes formed in the process. We demonstrate that alanine oligomers coordinate to the iridium carbene-based catalyst in three different ways, each giving rise to distinctive hydride signals. Moreover, the exact structures of the transient oligopeptide-catalyst complexes are oligomer-specific. This work gives a first insight into how the organometallic iridium-N-heterocyclic carbene-based parahydrogen hyperpolarization catalyst interacts with biopolymers that have multiple catalyst binding sites. A preliminary application example is demonstrated for oligopeptide detection in urine, a complex biological mixture. [ABSTRACT FROM AUTHOR]

This paper investigates the production of hydrocarbon resins by oligomerization in solution and suspension of the C9 fraction of by-products from oil refining. The disadvantage of existing technologies for oligomers by free radical oligomerization is the use of high reaction temperatures. The application of N-replaced amino peroxides as low-temperature initiators and a suspension oligomerization technology can reduce the temperature and duration of the reaction. The correlation between oligomerization parameters and yield and characteristics of oligomers has been established. Owing to this, it will be possible to set optimal conditions and predict the properties of the resulting products. The high values of the yield and bromine number correlation in oligomerization in solution (–0.98 and –0.95) and suspension (–0.83 and –0.80) indicate the course of the oligomerization reaction. The main factor influencing oligomerization in solution is the reaction temperature (correlation 0.80). The softening temperature of oligomers is in the range of 349‒353 K and does not depend on the oligomerization conditions in the solution (correlation indicator 0.18). Suspension oligomerization in the studied intervals does not depend on temperature (correlation −0.08) and initiator concentration (correlation 0.40). It is proved that in the studied intervals of variables, the yield of oligomers depends on the duration of the reaction (correlation 0.88). The color indicator of suspension oligomerization products at the studied intervals varies slightly and is 20–30 mg I2/100 ml. The established optimal conditions make it possible to effectively use oil refining by-products by synthesizing light oligomers. Under the established optimal conditions, the product yield is 22.7 % with oligomerization in solution and 19.4 % with suspension oligomerization. [ABSTRACT FROM AUTHOR]

The thermal stability of gun propellants is related to significant safety issues in their development, production, storage, or transportation. Therefore, the study of improving the thermal stability of propellants has urgent and important practical significance. In this work, glycidyl azide polymer (GAP) with a relative molecular weight of 330 was added to the gun propellant to prepare modified NG-NC-RDX gun propellants containing different contents of oligomeric GAP. The ability of the propellant to cause discoloration of methyl violet test paper due to thermal decomposition, as well as the thermal weight loss and adiabatic decomposition behavior of the propellant, were characterized. And the differential charge density of GAP and NG, as well as the free volume and microstructure of GAP/NC and NG/NC blends, were compared, and the mechanism by which GAP improves the thermal stability of the propellant was discussed. When the content of GAP in the propellant changes from 0% to 16%, the time for the methyl violet test paper to change from purple to orange is prolonged from 87 minutes to 98 minutes. The initial decomposition temperature of thermal weight loss increased from 164.7 °C to 176.4 °C. The maximum temperature rise rate during adiabatic decomposition decreased from 0.95 °C·min−1 to 0.12 °C·min−1. According to MS simulation calculations, GAP provides a larger free volume and improves the uniformity of the mesoscopic phase structure of the propellant. The covalent effect of bond C-N 3 in GAP molecules is stronger than that of bond O-NO 2 in NG molecules. The thermal stability of the NG-NC-RDX propellant increases with the addition of GAP, and it increases with the increase of GAP content in the propellant. This work provides a scheme for improving the thermal stability of the gun propellant and offers a way to reduce the risk of thermal stimulation. [Display omitted] [ABSTRACT FROM AUTHOR]

Inspired by inorganic oligomers, we herein develop a novel inorganic gel based on calcium oxalate oligomers, and the crystallization morphology has been studied initially in this paper. The prepared oligomer is translucent gel and can exist stably in ethanol, but in aqueous medium it will change from gel to powder. In the crystallization process, because of the volatile speed of solvent and capping agent TEA at different temperature, CaC2O4 oligomer gels (COOGs) exhibited distinct crystallization behavior and morphology. Compared with conventional inorganic crystallization, the crystallization process of the gel at room temperature shows a tendency to gradually extend to the inside of the gel. Moreover, the XRD pattern and SEM images shown that the COOGs achieved distinctly different crystal morphology under different temperature. These provide a preliminary research foundation for the crystallization behavior and control conditions of inorganic gels. [ABSTRACT FROM AUTHOR]

Pattern recognition receptor (PRR) is a kind of sensor which is mainly expressed on the surface of innate immune cells. It can recognize pathogen related molecular patterns (PAMPs) or damage related molecular patterns (DAMPs). The innate immune system uses pattern recognition receptors to recognize pathogenic microorganisms in periodontal tissues and transmit signals to downstream pathways in time, thus triggering immune responses and then eliminating them. PRR has many family members, including toll like receptor family (TLRs), C-type lectin receptor family (CLRs), retinoic acid induced gene I (RIG-I) like receptor family (RLRs) and nucleotide binding oligomer domain (NOD) like receptor family (NLRs). Among them, RLRs are cytoplasmic receptors that recognize dsRNA from RNA viruses and have little association with chronic periodontitis. In this paper, the classification and structure of TLRs, CLRs, NLRs and the role of signal transduction pathway in chronic periodontitis are reviewed. In order to enrich the pathogenesis of periodontitis, provide new ideas for the treatment and prevention of chronic periodontitis. [ABSTRACT FROM AUTHOR]

Tritan™ (a kind of glycol-modified polycyclohexylene dimethylene terephthalate) is a novel copolyester mainly in use for the production of sports bottles and food storage containers. Oligomers in three food-grade Tritan™ samples were identified after dissolution-precipitation by high performance liquid chromatography with diode array detection and mass spectrometry and quantified after alkaline hydrolysis to the monomers. The obtained overall oligomer content <1000 Da determined by hydrolysis ranged from 7.2 to 10.6 mg/g material. Three consecutive migration experiments were performed according to the Commission Regulation (EU) No 10/2011. Oligomer migration values decreased from first to third migration during all simulations. Less than 25 µg/kg (third migrate) were detected in bottle migrates when tested under room temperature storage conditions (40 °C, 24 h) with simulants 3% acetic acid, 20 and 50% ethanol and during hot-fill testing (70 °C, 2 h) with simulants 3% acetic acid and 20% ethanol, respectively, while 170 µg/kg were determined in 50% ethanol after migration at 70 °C for 2 h. Food storage containers that were labelled as microwave-suitable by the supplier were tested according to the Joint Research Centre recommendations for microwave dishware. A strong deformation of the containers as well as a loss of transparency were observed during the tests (100 °C, 2 h with 10% ethanol and 3% acetic acid in an autoclave, 121 °C, 30 min with sunflower oil), questioning the suitability of the material for microwave applications. Maximum oligomer migration was 379 µg/kg during the third migration (sunflower oil at 121 °C for 30 min). Based on the migration data and an in silico oligomer evaluation according to the threshold of toxicological concern concept, no exceedances of daily thresholds for oligomers are expected from a proper use of Tritan™ drinking bottles, even with hot drinks. [ABSTRACT FROM AUTHOR]

Lithium sulfur (Li–S) batteries have become the predominant energy storage devices of the future. However, the reasons why Li–S batteries have not been widely commercialized include the shuttle effect of polysulfides and the volume expansion of sulfur active substances. In this study, a binder with a stretchable 3D reticular structure was induced using inorganic oligomers. Potassium tripolyphosphate (PTP) has been used to powerfully connect the tamarind seed gum (TSG) chain through robust intermolecular forces due to the strong electronegativity of P–O− groups. With this binder, the volume expansion of sulfur active substances can be well restrained. In addition, a large amount of –OH groups in TSG and P–O− bonds in PTP can also effectively adsorb polysulfides and inhibit the shuttle effect. Therefore, the S@TSG-PTP electrode shows an improved cycle performance. When the sulfur loading is as high as 4.29 mg cm−2, the areal specific capacity can reach 3.37 mA h cm−2 after 70 cycles. This study highlights a new way for the binder design of high-loading sulfur electrodes. [ABSTRACT FROM AUTHOR]

Lignin, as the second largest biomass resource in the biomass plant, has the potential to be converted into other organic matter. Microbial mediated biocatalytic process in compost can depolymerize and utilize lignin environmentally. However, the source of lignin is complex and difficult to depolymerize, which limits the composting efficiency and reduces the humus quality. The purpose of the study was to find a breakthrough point by analyzing the difficulties of lignin depolymerization and reveal the potential contribution of lignin depolymerization to humus formation during composting. In this paper, the composition characteristics of lignin and the microbial action of lignin depolymerization were reviewed, including the microorganisms involved in lignin depolymerization, lignin depolymerases and microbial pathways, the potential pathway of lignin to form humus, and the environmental factors affecting lignin depolymerization during composting. Although the depolymerization ability of fungi on lignin has been studied for decades, the strict growth conditions of fungi limit their function during composting. Bacteria not only have good tolerance to environmental changes but also play an important role in the depolymerization of lignin. The results showed that the lignin depolymerization during composting was completed under the synergistic action of fungi and bacteria. Fungi deoxidized lignin β-O-4 and other bonding bonds by secreting depolymerases at low temperature, so as to depolymerize large molecules of lignin into oligomers and monomers, while bacteria degraded small molecules of lignin into nutrients that could be used by microorganisms at low temperature. At high temperature, bacteria can promote lignin depolymerization by secreting high temperature resistant depolymerases. Therefore, the study provides a theoretical basis for microbial cooperative depolymerization of lignin and formation of humus during composting. At the same time, it is necessary to add microbial agents and control the environment in different stages of compost to efficiently depolymerize lignin. [Display omitted] [ABSTRACT FROM AUTHOR]