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Objective: The aim of our study was to compare the clinical value of pathological spontaneous activity (PSA) in different thoracic paraspinal muscles (TPMs) in amyotrophic lateral sclerosis (ALS). Methods: A total of 116 ALS patients were retrospectively analyzed over 31 ± 8 months concerning the occurrence of PSA in T9–T11 TPM. The occurrence of PSA was correlated with pulmonary function and clinical disability. Results: The positive sharp wave (PSW) potentials were more frequently observed than fibrillation (fib) in T9–T11 segments. The PSA positive frequency of bulbar‐onset ALS (B‐ALS) is less than upper limb‐onset ALS (U‐ALS) and lower limb‐onset ALS (L‐ALS) at the levels of T10 and T11 TPM (p = 0.050, p = 0.001). The fibs/PSWs in TPM indicated high sensitivity and negative predictive value for forced vital capacity (FVC) < 80%. Linear correlation analysis indicated that PSA of TPM was associated with pulmonary ventilation function (PVF). Associations also exist between clinical parameters and PVF as well as the disease severity. Conclusions: The occurrence of T9‐TPM fibs/PSWs was correlated with clinical disability and is extremely helpful in implying an involvement of PVF. The T9‐TPM typically provided a good practical indicator for comprehensive disease evaluation, which was irrelevant to the site of onset. [ABSTRACT FROM AUTHOR]

The outstanding mechanical properties, light weight, and biodegradability of cellulose nanofibrils (CNFs) make them promising components of renewable and sustainable next-generation reinforced composite biomaterials and bioplastics. Manufacturing CNFs at a pilot scale requires disc-refining fibrillation of dilute cellulose fibers in aqueous pulp suspensions to shear the fibers apart into their nanodimensional forms, which is, however, an energy-intensive process. Here, we used atomistic molecular dynamics (MD) simulation to examine media that might facilitate the reduction of interactions between cellulose fibers, thereby reducing energy consumption in fibrillation. The most suitable medium found by the simulations was an aqueous solution with 0.007:0.012 wt.% NaOH:urea, and indeed this was found in pilot-scale experiments to reduce the fibrillation energy by ~21% on average relative to water alone. The NaOH:urea-mediated CNFs have similar crystallinity, morphology, and mechanical strength to those formed in water. The NaOH and urea act synergistically on CNFs to aid fibrillation but at different length scales. NaOH deprotonates hydroxyl groups leading to mesoscale electrostatic repulsion between fibrils, whereas urea forms hydrogen bonds with protonated hydroxyl groups thus disrupting interfibril hydrogen bonds. This suggests a general mechanism in which an aqueous medium that contains a strong base and a small organic molecule acting as a hydrogen-bond acceptor and/or donor may be effectively employed in materials processes where dispersion of deprotonable polymers is required. The study demonstrates how atomic-detail computer simulation can be integrated with pilot-scale experiments in the rational design of materials processes for the circular bioeconomy. [ABSTRACT FROM AUTHOR]

Fibrillation (Fib) is the most well-known sort of sporadic heartbeat. The sporadic termination of electrical impulses causes the atria (the top chambers in the heart) to tremble (or fibrillate). Cardiovascular arrhythmias happen in older people with coronary disease. Now and again, individuals with Fib have no manifestations, and their condition is just recognizable upon actual assessment. The issues include inconsistent heartbeats when the heart is reliably in a sporadic mood, as anticipated through the patient well-being observation framework (PHMS). The PHMS proposed calculation is ready to anticipate the inconsistent pulses by the location of the R top in electrocardiogram signals (ECG) and the unpredictable beat anticipated by utilizing the P wave along with the QRS complex with the T wave for one heart cycle. Hence, this paper proposes a hybrid Convolutional Neural Network (CNN) and Recurrent Neural Networks (RNN), termed hybrid C-RNN, to proceed with the characterization and determination of the arrhythmic beats. This work also analyzes the QRS peak variations, followed by classification. The practicability of the heartbeat characterization utilizing hybrid C-RNN is completed by metrics like accuracy, sensitivity, and specificity. The proposed model achieved an accuracy of 98.57%, sensitivity of 1%, and specificity of 9.565217e-01%. This is compared best with some existing approaches in the result section. [ABSTRACT FROM AUTHOR]

Copyright of Traditional Chinese Drug Research & Clinical Pharmacology is the property of Traditional Chinese Drug Research & Clinical Pharmacology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a good alternative to natural fibers and petroleum-derived fibers, Lyocell fibers draw increasing interests owing to its advantages of sustainable forest source, low carbon emission, high strength and comfort. However, Lyocell exhibits significant fibrillation behavior under friction, which seriously reduce product quality and limit its further development. Herein, dual crosslinking networks were innovatively constructed in Lyocell cellulose structure to enhance the interaction of cellulose macromolecular chains. Bifunctional reactive dyes were loaded in the inner part of Lyocell fiber to form a primary crosslinking network. Then, the cellulose interaction in Lyocell skin layer was further enhanced after the coating by cationic waterborne polyurethane. The mechanism was determined and results showed that durable dual crosslinking networks were formed in Lyocell cellulose structure. From scanning electron microscope (SEM) observation, fibrillation behavior of Lyocell fibers was effectively prevented by dual crosslinking networks. Meanwhile, the durability was evaluated, showing that the treated fabric maintained good anti-fibrillation performance after washing for 50 times. Furthermore, the interaction of dyes and fibers was also enhanced by the cationic polymer via electrostatic attraction force, realizing high dye utilization efficiency. Therefore, the method exhibits great potential in promoting the application of Lyocell fibers in greener textile. [ABSTRACT FROM AUTHOR]

Protein fibrils formed through self-assembly are expected to be used as a novel functional ingredient in food industry, on account of their abundant amino acids, straight morphology, and multi-level and multi-scale structures. The development and utilization of protein fibrils have become a research hotspot in the food field in recent years, notably the research on plant-derived protein self-assembled fibrils that are more in line with the needs of green and sustainable development has attracted considerable attention. In this paper, the formation mechanism and influencing factors of plant-derived protein fibrillization are introduced. Especially, the impact of fibrous self-assembly on the protein structure and techno -functional properties, as well as the application status and development prospects of protein fibrils in the food field are highlighted, with a view to provide a theoretical basis for the development and utilization of plant protein fibrils in the field of functional food. [ABSTRACT FROM AUTHOR]

This work investigates the potential utilisation of the agro-waste pineapple leaf fibre (PALF) as a green reinforcement in polypropylene (PP) composites. Generally, chemical treatment is used to clean the scratched PALF, and the effluents of those chemicals are discharged into nature. A new mechanical approach (carding) was used in this work to remove the remaining extraneous substances from the scratched and sun-dried PALF instead of using any chemical treatment. The percentage of sticky fibres and dust content decreased, and fibre breakage increased with the increasing number of carding passages. The individualized fibre properties were also influenced by the number of carding passages. The carding process reduced the diameter of PALF due to removal of extraneous materials. The tensile properties of raw PALF improved significantly until the fourth carding passage and further increase in the number of passages did not show any significant influence on the tenacity and modulus. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) confirmed the elimination of hemicellulose along with other gummy and waxy substances from the individualized PALF due to the carding action. The crystallinity % also increased after the carding process due to the removal of amorphous substances. As the reinforcement-matrix interfacial shear strength (IFSS) strongly influences the physico-mechanical properties of composites, IFSS of carded PALF reinforced finer and coarser PP fibre micro-bonded composites was also studied using the single fibre pull-out test (SFPT). Among different composites, the fourth carding passed PALF-reinforced finer PP fibre micro-bonded composite showed the highest IFSS. Additionally, the load- extension curves and SEM images of the tensile pulled-out surface were investigated to study the interfacial adhesion between PALF and PP micro-droplets. The increased surface roughness of PALF due to the carding action resulted in an improvement in the IFSS of PALF-reinforced PP micro-bonded composites. [ABSTRACT FROM AUTHOR]

Amyloid fibroproliferation leads to organ damage and is associated with a number of neurodegenerative diseases affecting populations worldwide. There are several ways to protect against fibril formation, including inhibition. A variety of organic compounds based on molecular recognition of amino acids within the protein have been proposed for the design of such inhibitors. However, the role of macrocyclic compounds, i.e., thiacalix[4]arenes, in inhibiting fibrillation is still almost unknown. In the present work, the use of water-soluble thiacalix[4]arene derivatives for the inhibition of hen egg-white lysozyme (HEWL) amyloid fibrillation is proposed for the first time. The binding of HEWL by the synthesized thiacalix[4]arenes (logKa = 5.05–5.13, 1:1 stoichiometry) leads to the formation of stable supramolecular systems capable of stabilizing the protein structure and protecting against fibrillation by 29–45%. The macrocycle conformation has little effect on protein binding strength, and the native HEWL secondary structure does not change via interaction. The synthesized compounds are non-toxic to the A549 cell line in the range of 0.5–250 µg/mL. The results obtained may be useful for further investigation of the anti-amyloidogenic role of thiacalix[4]arenes, and also open up future prospects for the creation of new ways to prevent neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Lyocell fibers are currently claimed as green fibers with good application prospects, but the major problem of fibrillation restricts further promotion and application. In this study, based on the theory of hydration lubrication at the solid/liquid interface, hexamethylene-diisocyanate trimer (HDIt), polyethylene glycol (PEG), and butanone oxime (MEKO) were used to synthesize a reactive hydrophilic triblock polyurethane (RHT-PU). RHT-PU could construct a water lubrication layer on the lyocell fiber surface via H-bonding between polyoxyethylene ether and water molecules, reducing the coefficient of friction (CoF) of the fiber interface in the water. It was found that PEG molecular weight and grafting density had significant effects on the CoF of modified fabrics, with CoFs decreased with increased PEG molecular weight and grafting density. In water, the CoFs of fabrics modified by RHT-PU were reduced from 0.45 to 0.32 and maintained lower CoFs at higher temperature and higher normal loads. After mechanical friction and household washing tests, the surface abrasion of modified fabrics were significantly improved and color fading grade of fabrics raised from 3 grade to 4–5 grade. Construction of water-lubricated interfaces effectively reduced fibrillation. [ABSTRACT FROM AUTHOR]

Abstract Oil palm trunk (OPT) is an inexpensive, abundantly available by-product of palm oil production which is typically not put to material use. Due to its comparably high cellulose content, OPT represents a suitable raw material for the preparation of cellulose nanofibrils (CNFs). Aiming for full utilization of the raw material and minimized energy demand, non-delignified and partially delignified (alkali-pretreated) OPT was subjected to mechanical fibrillation in the present study. As compared to CNFs from fully delignified OPT, the lignin-rich microfibrils obtained by this approach generally showed higher average fibril diameters, lower thermal stability as well as lower viscosity, and higher sedimentation rate in suspension. However, the combination of alkali-pretreatment and fibrillation by disc-grinding and subsequent high-pressure homogenization resulted in fibrils with properties similar to those of CNFs from fully delignified OPT. As proven by IR-spectroscopy, thermogravimetry and chemical composition analysis, alkali-treated OPT fibrils still contained substantial amounts of residual lignin which could, for instance, act as a natural coupling agent or binder in composite applications. Moreover, the facile delignification process applied herein requires far less chemicals and energy than conventional pulping and is thus beneficial from both the economic and ecological perspective.

The article shows the possibility of intensifying the process of producing microcrystalline cellulose via pregrinding of fibrous semi-finished products before hydrolysis. The technological factors determining the grinding of fibrous materials have been considered. The efficiency of the microcrystalline cellulose production process is influenced by the choice of its production technology. For grinding, a semi-industrial disc mill with a tacking with rectilinear and curvilinear knives has been used. Multiphysics models of the flow of fibrous mass in the grinding zone of a disc mill with different knife tacking patterns have been constructed. The morphological properties of the fiber have been measured on the Morfi Neo automatic fiber analyzer after grinding to 65 °SR. The nature of the change in the properties of bleached sulfate hardwood and softwood cellulose has been analyzed. It has been found that it is identical for all degrees of grinding, but the quantitative characteristics change to the greatest extent when grinding softwood cellulose using a tacking with rectilinear knives: the weighted average length of fibers decreases by 17 %, the width – by 14 %; the content of broken fibers increases by 22 %, the content of fines along the length – by 67 % and the fibrillation index – by 1.9 times. A comparative analysis of the values of the degree of polymerization depending on the knife tacking pattern has been carried out. The conditions for producing microcrystalline cellulose after grinding the fibrous mass in a semi-industrial disc mill, depending on the degree of grinding, have been determined. It has been shown that with an increase in the degree of grinding of the fibrous mass from 15 to 65 °SR, the degree of polymerization of microcrystalline cellulose decreases from 272 to 120, the concentration of hydrochloric acid – from 2.5 to 1.5 N and the duration of hydrolysis – from 120 to 90 min. The developed method for producing microcrystalline cellulose makes it possible to reduce the cost of chemical treatment of the fibrous mass (acid concentration, treatment duration and hydrolysis temperature) by 1.5 times.

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, we investigated the complexation of bioactive isoflavones, specifically biochanin A (BCA) and genistein (GEN), with hen egg white lysozyme (HEWL) and explored their inhibitory effects on HEWL modification using a combination of multi-spectroscopic and computational methods. The observed binding affinity was of a moderate nature (on the order of 104 M−1), and a static quenching mechanism was identified in the fluorescence quenching process. Notably, the binding constant (Kb) for GEN (4.449 ± 0.262 × 104 M−1) was found to be higher than that for BCA (3.707 ± 0.108 × 104 M−1) towards HEWL. Our spectroscopic measurements, complemented by molecular docking calculations, suggested the involvement of Trp62 in the binding site of the isoflavones within the geometry of HEWL. The micro-environment surrounding the Trp-residues exhibited an increase in hydrophilicity, as indicated by Synchronous fluorescence (SFS) and three-dimensional fluorescence (3D) studies. Interestingly, circular dichroism (CD) studies revealed no marked alteration in the secondary structure of HEWL upon binding with the isoflavones. Furthermore, our investigation into the interaction patterns, employing FTIR and molecular docking studies, revealed a predominance of hydrogen bonding and hydrophobic interactions. Beyond the binding study, the isoflavones demonstrated a promising inhibitory effect on the d-ribose-mediated glycation of HEWL, as well as on HEWL fibrillation, as evidenced by fluorescence emission studies. Our findings not only exhibited an excellent correlation with experimental observations but also provided precise insights into the location and dynamics of isoflavones within the binding site through detailed analyses of molecular docking and molecular dynamics simulation data.

The global burden caused by cardiovascular disease is substantial, with heart disease representing the most common cause of death around the world. There remains a need to develop better mechanistic models of cardiac function in order to combat this health concern. Heart rhythm disorders, or arrhythmias, are one particular type of disease which has been amenable to quantitative investigation. Here we review the application of quantitative methodologies to explore dynamical questions pertaining to arrhythmias. We begin by describing single-cell models of cardiac myocytes, from which two and three dimensional models can be constructed. Special focus is placed on results relating to pattern formation across these spatially-distributed systems, especially the formation of spiral waves of activation. Next, we discuss mechanisms which can lead to the initiation of arrhythmias, focusing on the dynamical state of spatially discordant alternans, and outline proposed mechanisms perpetuating arrhythmias such as fibrillation. We then review experimental and clinical results related to the spatio-temporal mapping of heart rhythm disorders. Finally, we describe treatment options for heart rhythm disorders and demonstrate how statistical physics tools can provide insights into the dynamics of heart rhythm disorders.

Abstract Background The impact of chronic kidney disease (CKD) on atrial fibrillation outcomes (AF) is not well understood. Methods We conducted analyses of comorbid AF and CKD related death in the United States from 1999 to 2020 using descriptive epidemiology. Results Age‐adjusted mortality rates (AAMR) per 100,000 increased from 0.39 in 1999 to 1.65 in 2020. Non‐Hispanic populations (1.01) and nonmetropolitan areas (1.08) had higher AAMRs compared to Hispanic (0.62) and metropolitan (0.97) areas. Midwestern (1.11) and Western (1.13) US regions recorded the highest AAMRs. Conclusions These findings highlight the need for interventions to address AF death disparities in patients with CKD.

Lignocellulose nanofibers (LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the important role of these two stages. This review discussed the interaction between lignin and chemicals in the pretreatment stage, and discovered the general law of the effect of lignin in the mechanical fibrillation stage. Lignin exhibits both promotion and inhibition effects on mechanical fibrillation, and the mutual competition between the two effects ultimately affects the energy consumption, morphology and yield of LCNFs. Furthermore, the recent research progress related to the contributions of lignin on the functional application of LCNFs was summarized, aiming to provide profound guidance for the preparation and application of LCNFs.

Kraft pulp is the most common and economically advantageous raw material for making cellulose nanofibers (CNFs). However, it is revealed that high temperatures and pressures during kraft cooking cause the aggregation of cellulose microfibrils, which reduces the nanofibrillation capability of kraft pulp. Herein, we studied the optimum kraft cooking conditions required to obtain uniform CNFs by preventing aggregation. The fibrillation ability was compared with that of undried pulp treated with purification method only. Suspensions of undried pulps were mechanically fibrillated for various durations. The degree of fibrillation was evaluated by sedimentation, morphology, and water retention values. Kraft pulp cooking at a H-factor of approximately 650 for 140 °C, 160 °C and 170 °C resulted in less fibrillation than in the Wise-based pulp, even at low temperatures such as 140 °C. In contrast to expectations, high matrix substances with lignin contents of 30% did not prevent aggregation of the cellulose microfibrils. The production of CNFs requires a pulping technique for extracting cellulose without aggregation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ovalbumin (OVA), accounting for 50% of proteins in egg white, is a kind of high‐quality protein with excellent nutritional and processing functions. Acid heat treatment will induce the deformation and filtration of OVA, endowing it with improved functionality. However, the molecular kinetic process during the fibrillation of OVA and the application of the fabricated OVA fibrils (OVAFs) have not been thoroughly studied and revealed. RESULTS: In this study, the fabrication mechanism and the application OVAFs as an interfacial stabilizer and polyphenol protector were investigated. Acidic (pH 3.0) heat treatment was used to induce the fibrillation of OVA, and thioflavin T fluorescence intensity, molecular weight distribution, and the tertiary and secondary structures of OVAF samples were recorded to determine the fibrillation efficiency and the molecular mechanism. The results showed that, in the initial stage of fibrillation, OVA first hydrolyzed to oligopeptides, accompanied by the exposure of hydrophobic domains. Then, oligopeptides were connected by disulfide bonds to form primary fibril monomers. Hydrophobic interaction and hydrogen bonding may participate in the further polymerization of the fibrils. The fabricated OVAFs were characterized by a β‐sheet‐rich structure and possessed improved emulsifying, foaming, and polyphenol protection ability. CONCLUSION: The research work was meaningful for exploring the application of globular water‐soluble OVA in an emerging nutritious food with novel texture and sensory properties. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Mitral valve prolapse (MVP) is associated with aggravated risk of ventricular tachycardia (VT), ventricular fibrillation (VF) and sudden cardiac death (SCD). There is a lack of specific guideline recommendation regarding risk stratification and management, despite multiple proposed high-risk phenotypes. We performed systematic review and meta-analysis to evaluate high-risk phenotypes for malignant arrhythmias in patients with MVP. We comprehensively searched the databases of MEDLINE, SCOPUS, and EMBASE from inception to April 2023. Included studies were cohort and case-control comparing between MVP patients with and without VT, VF, cardiac arrest, ICD placement, or SCD. Data from each study were combined using the random-effects. Pooled odds ratios (OR) and 95% confidence intervals (CI) were calculated. Nine studies from 1985 to 2023 were included involving 2,279 patients with MVP. We found that T-wave inversion (OR 2.52; 95% CI: 1.90–3.33; p < 0.001), bileaflet involvement (OR 2.28; 95% CI: 1.69–3.09; p < 0.001), late gadolinium enhancement (OR 17.05; 95% CI: 3.41–85.22; p < 0.001), mitral annular disjunction (OR 3.71; 95% CI: 1.63–8.41; p < 0.002), and history of syncope (OR 6.96; 95% CI: 1.05–46.01; p = 0.044), but not female (OR 0.96; 95% CI: 0.46–2.01; p = 0.911), redundant leaflets (OR 4.30; 95% CI: 0.81–22.84; p = 0.087), or moderate-to-severe mitral regurgitation (OR 1.24; 95% CI: 0.65–2.37; p = 0.505), were associated with those events. Bileaflet prolapse, T-wave inversion, mitral annular disjunction, late gadolinium enhancement, and history of syncope are high-risk phenotypes among population with MVP. Further research is needed to validate the risk stratification model and justify the role of primary prophylaxis against malignant arrhythmias. [ABSTRACT FROM AUTHOR]

Handmade paper has been around for centuries. In Asia, Europe, and other parts of the world, the means of creating handmade paper depend largely on traditional equipment and other industrial machines. In Ghana, the means of creating handmade paper is through a tedious process of hand beating the bast fiber of the Kyenkyen tree. This resulted in the production of a proto-paper known as the bark cloth. This traditional method has almost become extinct with the influx of imported industrial papers. Therefore the purpose of this study was to seek a solution to this problem through the possible design and fabrication of a paper pulp-making machine daubed the Ada Beater. Thus getting vital tools for making art, print, and papermaking. The paper explored practice-based research methodology to fabricate a papermaking machine known as the Ada Beater. The results showed that the machine can be fabricated and made to produce improved papers of archival quality derived from various plant sources in Ghana. It is recommended that this homegrown know-how should be made available to artists and art teachers for the teaching and use of handmade paper for artistic purposes.

Petroleum-based materials are often used in the packaging industry. However, the single use value of such products can be problematic with regard to proper waste disposal. As such, molded pulp packaging can be used as an alternative, given its ease of recycling, composting, and eventual biodegradation. In this work, we aims to study the pulp properties of sunn hemp and its usage as molded pulp products. For this purpose, unbleached beaten and unbeaten soda pulps derived from the whole stem of sunn hemp were examined for their fiber morphology, fibrillation, fiber classification, and physical properties. The sunn hemp pulp was subsequently molded using a batch molding machine. To determine the hydrophobicity of the molded pulp products, the molded samples were manufactured with and without additives. Finally, some properties of the molded pulp products were examined and compared with the commercially available bleached bagasse molded pulp products. It was observed that the molded products made from sunn hemp pulp with additives had a higher water contact angle than that of the commercial products. In terms of general usage, the molded products from sunn hemp pulp with additives were found to be capable of storing hot water, hot cooking oil, as well as microwaving water. We concluded that the sunn hemp pulp could be used as an alternative fibrous raw material in the production of molded pulp packaging.

Background: The impact of chronic kidney disease (CKD) on atrial fibrillation outcomes (AF) is not well understood. Methods: We conducted analyses of comorbid AF and CKD related death in the United States from 1999 to 2020 using descriptive epidemiology. Results: Age-adjusted mortality rates (AAMR) per 100,000 increased from 0.39 in 1999 to 1.65 in 2020. Non-Hispanic populations (1.01) and nonmetropolitan areas (1.08) had higher AAMRs compared to Hispanic (0.62) and metropolitan (0.97) areas. Midwestern (1.11) and Western (1.13) US regions recorded the highest AAMRs. Conclusions: These findings highlight the need for interventions to address AF death disparities in patients with CKD. [ABSTRACT FROM AUTHOR]

The characteristics of fiber morphology and paper structure are critical to the barrier properties of food packaging paper. Herein, this study aimed to use pulp fibrillation, paper semi-dry pressing and carboxymethyl starch (CMS) coating to flatten the fibers, which were formed on the paper surface with good barrier properties due to the tight bond between fibers. The results showed that the permeability of paper was reduced by 87.56%, from 81.44 μm/Pa·s to 10.13 μm/Pa·s after the pulp fibrillation treatment (60 °SR). Moreover, semi-dry pressing treatment contributed to decreasing the water vapor transmission coefficient (WVP) by 50.98% to 2.74 × 10−10 g/m·s·Pa, and the oxygen permeation coefficient (OP) decreased by 98.04% to 1.93 × 10−14 cm3·cm/cm2·s·Pa. After coating the paper surface with titanium dioxide (TiO2) and CMS, the WVP of the paper was further reduced to 1.55 × 10−10 g/m·s·Pa, and OP was reduced to 0.19 × 10−14 cm3·cm/cm2·s·Pa. These values were 72.27% and 99.8% lower than those of the original paper, respectively. Therefore, through pulp fibrillation, semi-dry pressing of paper, TiO2 filling, and surface coating with CMS, there is no need to use synthetic polymer surface film-forming agents to achieve the high barrier properties that are required for low water and oxygen molecules permeation in food packaging paper.

This paper presents the results of an assessment of the morphological characteristics of semi-finished wood-fibre products obtained from waste fibreboard using a rotary cutting machine by dry grinding. The work has established the influence of machine design parameters, such as the gap between the rotor and stator cutters and the angle of the stator cutter contact with the raw materials, on the mass fraction of small fibres and fines in wood-fibre pulp. These parameters determine the main structural characteristics of boards and ensure fibre bonding. The paper describes the collision of single secondary wood fibres that leads to the development of primary cracks, contributing to external and internal fibrillation in the absence of high temperatures and pressure without using chemical additives or water and steam.

Introduction: Misfolding of amyloidogenic proteins is a molecular hallmark of neurodegenerative diseases in humans. A detailed understanding of the underlying molecular mechanisms is mandatory for developing innovative therapeutic approaches. The bovine PI3K-SH3 domain has been a model system for aggregation and fibril formation.Methods: We monitored the fibril formation kinetics of low pH-denatured recombinantly expressed [U-13C, 15N] labeled bovine PI3K-SH3 by a combination of solution NMR, high-resolution magic angle spinning (HR-MAS) NMR and solid-state NMR spectra. Solution NMR offers the highest sensitivity and, therefore, allows for the recording of two-dimensional NMR spectra with residue-specific resolution for individual time points of the time series. However, it can only follow the decay of the aggregating monomeric species. In solution NMR, aggregation occurs under quiescent experimental conditions. Solid-state NMR has lower sensitivity and allows only for the recording of one-dimensional spectra during the time series. Conversely, solid-state NMR is the only technique to detect disappearing monomers and aggregated species in the same sample by alternatingly recoding scalar coupling and dipolar coupling (CP)-based spectra. HR-MAS NMR is used here as a hybrid method bridging solution and solid-state NMR. In solid-state NMR and HR-MAS NMR the sample is agitated due to magic angle spinning.Results: Good agreement of the decay rate constants of monomeric SH3, measured by the three different NMR methods, is observed. Moderate MAS up to 8 kHz seems to influence the aggregation kinetics of seeded fibril formation only slightly. Therefore, under sufficient seeding (1% seeds used here), quiescent conditions (solution NMR), and agitated conditions deliver similar results, arguing against primary nucleation induced by MAS as a major contributor. Using solid-state NMR, we find that the amount of disappeared monomer corresponds approximately to the amount of aggregated species under the applied experimental conditions (250 µM PI3K-SH3, pH 2.5, 298 K, 1% seeds) and within the experimental error range. Data can be fitted by simple mono-exponential conversion kinetics, with lifetimes τ in the 14–38 h range. Atomic force microscopy confirms that fibrils substantially grew in length during the aggregation experiment. This argues for fibril elongation as the dominant growth mechanism in fibril mass (followed by the CP-based solid-state NMR signal).Conclusion: We suggest a combined approach employing both solution NMR and solid-state NMR, back-to-back, on two aliquots of the same sample under seeding conditions as an additional approach to follow monomer depletion and growth of fibril mass simultaneously. Atomic force microscopy images confirm fibril elongation as a major contributor to the increase in fibril mass.

The adhesion of pressure-sensitive adhesives (PSAs) is a complex phenomenon that can be understood through the characterization of different properties, including viscoelastic, mechanical, and fracture properties. The aim of the present paper is to determine the viscoelastic behaviour of an acrylic PSA and place it in the viscoelastic window, as well as to determine the tensile strength of the material. Additionally, different numbers of stacked adhesive layers and two crosshead speeds were applied to characterize the tensile strength of the adhesive in the different conditions. Adding a new interface between layers showed a negative influence in the tensile strength, while a higher crosshead speed implied a considerable increase in the same value. Finally, double cantilever beam (DCB) fracture tests were performed, and the J-integral approach was used to evaluate the fracture energy throughout the tests. The substrate roughness, the number of stacked layers, and the thickness of the PSA proved to decrease the performance of the PSA in fracture tests. While tensile bulk tests in viscoelastic materials are not easily found in the literature, as well as DCB tests, for fracture characterization, the obtained results allowed for the characterization of those properties in an acrylic PSA. [ABSTRACT FROM AUTHOR]

Automatic external defibrillators (AEDs) are devices intended for emergency first aid by both qualified and non-medical personnel. Statistical studies prove that more than 90% of accidents occur outside hospitals, and in 70% of them the cause is the occurrence of heart fibrillation - loss of the normal rhythm, which can have a fatal outcome. The surest way to stop fibrillation is to apply a short-term powerful electrical impulse (electroshock) through electrodes placed on the victim's chest. The first 8-10 minutes are of decisive importance for the victim's life, which leads to the need to provide AED in large public areas, to be used by the first witnesses of the accident - pre-trained persons, such as policemen, security guards, volunteers. Objective: To investigate awareness and public attitudes to participate in early defibrillation training in special programs. Material and methods: 175 respondents from 6 regional cities in Northern Bulgaria were studied in the period May - July 2023. Survey, historical and statistical methods were used. Results and discussion: 54.3% of the respondents have no information about AAD and its application. In the surveyed cities, a total of 78.9% of respondents do not know and have not seen automatic external defibrillators installed in public places. 72% of respondents believe that medical personnel or citizens with non-medical education, trained in special programs, should work with these devices. 61.7% do not have information on conducting training for early defibrillation under specialized programs in the relevant regional centers. The information received and the demonstration in places allowed 81.7% of the respondents to perceive the idea of placing VAD in public places as very good and good, and 55.4% of the respondents would participate in specialized training, because saving human life is extremely humane. Conclusion: Awareness and education increase the chances of survival for people with cardiac arrest. Organized trainings are provided to employees and even students. With this initiative, it is possible to increase the chance of survival of people with cardiac arrest in the future. The use of automated external defibrillators is an important advance in effectively saving human lives. [ABSTRACT FROM AUTHOR]

As a novel and flexible actuator, the water hydraulic artificial muscle (WHAM) has become at the forefront of bionic robot research. In order to explore the fatigue behavior of WHAM, the lifetime of WHAM was analyzed based on the crack propagation of neoprene rubber and the S‐N curve of aramid fiber. Meanwhile, WHAM's fatigue tests were carried out, and the fatigue life exceeded 56,000 cycles under the pressure of 2 MPa and the elastic load of 1030.7 N/mm. In addition, WHAM's fatigue failure is represented as the burst of the rubber tube after fiber fracture. Moreover, heavy load aggravates fibrillation that leads to severe fracture of fibrils under similar friction, and the fatigue life of WHAM is aggravatingly shortened by the coupling of fibrillation and friction. Finally, an empirical model of fatigue life was obtained, which can predict the lifetime of WHAM. Highlights The fatigue behavior of WHAMs was analyzed based on the crack propagation of rubber and the S‐N curve of aramid fiber.The fatigue behavior of WHAMs is represented as the burst of rubber tube after fiber strands fracture.Heavy load aggravates fibrillation that leads to severe fracture of fibrils under similar friction, and the fatigue life of WHAMs is aggravatingly shortened by the coupling of fibrillation and friction.An empirical model of fatigue life was obtained, which can predict the fatigue life of WHAMs. [ABSTRACT FROM AUTHOR]

Petroleum-based materials are often used in the packaging industry. However, the single use value of such products can be problematic with regard to proper waste disposal. As such, molded pulp packaging can be used as an alternative, given its ease of recycling, composting, and eventual biodegradation. In this work, we aims to study the pulp properties of sunn hemp and its usage as molded pulp products. For this purpose, unbleached beaten and unbeaten soda pulps derived from the whole stem of sunn hemp were examined for their fiber morphology, fibrillation, fiber classification, and physical properties. The sunn hemp pulp was subsequently molded using a batch molding machine. To determine the hydrophobicity of the molded pulp products, the molded samples were manufactured with and without additives. Finally, some properties of the molded pulp products were examined and compared with the commercially available bleached bagasse molded pulp products. It was observed that the molded products made from sunn hemp pulp with additives had a higher water contact angle than that of the commercial products. In terms of general usage, the molded products from sunn hemp pulp with additives were found to be capable of storing hot water, hot cooking oil, as well as microwaving water. We concluded that the sunn hemp pulp could be used as an alternative fibrous raw material in the production of molded pulp packaging. [ABSTRACT FROM AUTHOR]

Abstract Background Multiple methods of quantifying social determinants of health exist, such as the social vulnerability index (SVI). We assess the impact of the SVI on atrial fibrillation (AF)‐related cardiovascular disease mortality. Methods CDC databases were used to obtain mortality and SVI information. Age‐adjusted mortality rates (AAMR) were compared among all US counties, aggregated by SVI quartiles. Results AAMR was not increased in counties within the highest SVI quartile, consistent across gender and geographic subgroups. Conclusions Increased SVI is a poor marker to predict mortality outcomes associated with AF.

Wild-type human SOD1 forms a highly conserved intra-molecular disulfide bond between C57-C146, and in its native state is greatly stabilized by binding one copper and one zinc atom per monomer rendering the protein dimeric. Loss of copper extinguishes dismutase activity and destabilizes the protein, increasing accessibility of the disulfide with monomerization accompanying disulfide reduction. A further pair of free thiols exist at C6 and C111 distant from metal binding sites, raising the question of their function. Here we investigate their role in misfolding of SOD1 along a pathway that leads to formation of amyloid fibrils. We present the seeding reaction of a mutant SOD1 lacking free sulfhydryl groups (AS-SOD1) to exclude variables caused by these free cysteines. Completely reduced fibril seeds decreasing the kinetic barrier to cleave the highly conserved intramolecular disulfide bond, and accelerating SOD1 reduction and initiation of fibrillation. Presence or absence of the pair of free thiols affects kinetics of fibrillation. Previously, we showed full maturation with both Cu and Zn prevents this behavior while lack of Cu renders sensitivity to fibrillation, with presence of the native disulfide bond modulating this propensity much more strongly than presence of Zn or dimerization. Here we further investigate the role of reduction of the native C57-C146 disulfide bond in fibrillation of wild-type hSOD1, firstly through removal of free thiols by paired mutations C6A, C111S (AS-SOD1), and secondly in seeded fibrillation reactions modulated by reductant tris (2-carboxyethyl) phosphine (TCEP). Fibrillation of AS-SOD1 was dependent upon disulfide reduction and showed classic lag and exponential growth phases compared with wild-type hSOD1 whose fibrillation trajectories were typically somewhat perturbed. Electron microscopy showed that AS-SOD1 formed classic fibrils while wild-type fibrillation reactions showed the presence of smaller "sausage-like" oligomers in addition to fibrils, highlighting the potential for mixed disulfides involving C6/C111 to disrupt efficient fibrillation. Seeding by addition of sonicated fibrils lowered the TCEP concentration needed for fibrillation in both wild-type and AS-SOD1 providing evidence for template-driven structural disturbance that elevated susceptibility to reduction and thus propensity to fibrillate.

Amyloid fibroproliferation leads to organ damage and is associated with a number of neurodegenerative diseases affecting populations worldwide. There are several ways to protect against fibril formation, including inhibition. A variety of organic compounds based on molecular recognition of amino acids within the protein have been proposed for the design of such inhibitors. However, the role of macrocyclic compounds, i.e., thiacalix[4]arenes, in inhibiting fibrillation is still almost unknown. In the present work, the use of water-soluble thiacalix[4]arene derivatives for the inhibition of hen egg-white lysozyme (HEWL) amyloid fibrillation is proposed for the first time. The binding of HEWL by the synthesized thiacalix[4]arenes (logKa = 5.05–5.13, 1:1 stoichiometry) leads to the formation of stable supramolecular systems capable of stabilizing the protein structure and protecting against fibrillation by 29–45%. The macrocycle conformation has little effect on protein binding strength, and the native HEWL secondary structure does not change via interaction. The synthesized compounds are non-toxic to the A549 cell line in the range of 0.5–250 µg/mL. The results obtained may be useful for further investigation of the anti-amyloidogenic role of thiacalix[4]arenes, and also open up future prospects for the creation of new ways to prevent neurodegenerative diseases.

This paper presents the results of an assessment of the morphological characteristics of semi-finished wood-fibre products obtained from waste fibreboard using a rotary cutting machine by dry grinding. The work has established the influence of machine design parameters, such as the gap between the rotor and stator cutters and the angle of the stator cutter contact with the raw materials, on the mass fraction of small fibres and fines in wood-fibre pulp. These parameters determine the main structural characteristics of boards and ensure fibre bonding. The paper describes the collision of single secondary wood fibres that leads to the development of primary cracks, contributing to external and internal fibrillation in the absence of high temperatures and pressure without using chemical additives or water and steam. [ABSTRACT FROM AUTHOR]

Fabrication of self-reinforced polyethylene terephthalate (PET) has been achieved through the in situ generation of PET fibrils via a spun bond process. The reinforcement fibrils created from the PET with higher Tm are made from a unique in situ processing method. As a result, the fibrils are well dispersed and distributed in the lower Tm PET matrix. The high degree of molecular similarity affords perfect interfaces between the matrix and dispersed phase, leading to excellent stress transfer from the matrix to the dispersed fibrils. While the extremely large interfaces from the nanofibrillation process can maximize the advantage of the excellent molecular similarity of the self-reinforced polymeric composites, few studies have been conducted to research nanofibrillar self-reinforced polymeric composite systems. Hence, as a proof of concept, this work provides new insight into an approach for developing a self-reinforced polymeric system with a nanofibrillation process. This process increases the tensile strength of PET composites by up to 15% compared to composites made by a simple blending process and 47% higher than neat PET. Furthermore, extensional viscosity measurements show a strain-hardening behavior in the fibrillated PET composites not observed in the neat PET and showed minimal behavior in un-fibrillated PET composites. The foam process results reveal that the presence of PET fibrils in PET improves the expansion ratio as well as the cell density of the PET composites. Specifically, compared to the PET composite foams without the fibrillation process, fibrillated PET composite foams showed up to 3.7 times higher expansion ratios and one to two orders of magnitude higher cell densities. In thermal conductivity measurements, fibrillated PET composite foams achieved thermal conductivity of as low as 0.032 W/mK. [ABSTRACT FROM AUTHOR]

Palmyra fibers are found to be the renewable and sustainable fiber in textile applications. These fibers possess good tensile strength and found to be used as a natural reinforcement material for composites. The main objective of this work is to extract and treat the fibers with varying concentrations of NaOH (2%,3%,4%& 5%) to evaluate the mechanical properties, surface morphology, and fiber orientation. The observations in SEM images denote the removal of impurities like hemi cellulose and lignin after the alkali treatment. 4% NaOH-treated fibers results in higher tensile strength (63.43 MPa) and a further increase in alkali concentration to 5% results in a reduction of the tensile strength (62.65 MPa). For all the treated fibers, elongation at break was found to be higher than the untreated one. The orientation in the fiber structure improves after the alkali treatment up to 4% and a further increase in alkali concentration leads to a decrease in the orientation which was observed through X-ray diffraction studies.

Parkinson’s disease (PD) is a progressive neurodegenerative disease that is characterized by the loss of dopamine. Since dopamine has trouble entering the blood–brain barrier, the utilization of dendrimers and other nanomaterials is considered for conjugating the neurotransmitter and other PD drugs. Dendrimers are three-dimensional, hyper-branched structures that are categorized into several generations. Alpha-synuclein (ASN) is the protein involved in regulating dopaminergic functions and is the main aggregate found inside Lewy bodies. Different types of dendrimers have shown efficacy in disrupting the formation of unstable beta structures of ASN and fibrillation. The conjugation of PD drugs into nanomaterials has elicited a prolonged duration of action and sustained release of the drugs inside the BBB. The objectives of this study are to review the applications of a dendrimer-based drug delivery system in addressing the root cause of Parkinson’s disease and to emphasize the delivery of anti-Parkinson’s drugs such as rotigotine, pramipexole and dopamine using routes of administration other than oral and intravenous.

Objectives: To examine whether the left atrial (LA) mechanical function is a predictor for the development of post-operative atrial fibrillation (POAF) following cardiac surgery. Background: POAF is an important and frequent complication of cardiac surgery. The relationship between LA mechanical function and POAF is not well understood. We examined the relationship between pre-operative LA function and POAF in patients without a history of atrial fibrillation. Method: our study was a prospective study that included 80 subjects who were eligible for cardiac surgery. pre-operative transthoracic echocardiograms were done for all subjects which were followed up for the occurrence of atrial fibrillation postoperatively. They were divided postoperatively into two groups. Group1: patients who developed POAF .group 2: patients who did not develop AF post operatively. The left atrial maximum volume and left atrial minimum volume were measured preoperatively and indexed to body surface area .LA TEF was calculated as: {[(LAVmax - LAVmin)/LAVmax] 100%}. Results: POAF occurred in 35% of subjects. Mean LA TEF in group 1 was 43.43%±4.38 versus 56.48±6.20% in group 2. Mean LAVmaxI in group 1 was 2 2 32.40±4.97 ml/m versus 26.66±6.26 ml/m in group 2. Mean LAVminI in group 1 was 17.17±3.62 ml/m² versus 10.49±3.56ml/m². LA TEF was lower in patients with POAF compared with those without POAF (43 ± 4.38% vs. 56.48± 6.2%, p 0.000). Conclusions: preoperative assessment of LA TEF is an independent predictor of POAF. Pre operative medical prophylaxis can be given to those with poor left atrial mechanical function. [ABSTRACT FROM AUTHOR]

This study aims to encourage the large scale production of micro-cellulose fibres (MCF), especially in developing economies. Micro-fibres have been extracted from banana pseudo-stem agro-wastes to valorise the latter. The particularity of this study is that a commercial food wet grinder, an equipment necessitating less investment cost as compared to the traditional supermass colloider (SMC) machine, has been employed to yield micro-fibres. For enabling maximum controllability of the process, the effect of two grinding parameters (the gap distance and the number of passes) were investigated. The results revealed the viability of such a mechanical equipment: from SEM results, 95% reduction in fibre diameter (comparable to the 99% size reduction for the SMC machine) and from XRD results, high percentage crystallinity (76–80% corresponding to an increase of 25–30%) were obtained. The optimal conditions resulting in these conditions were: smallest possible gap distance (800 µm) and highest number of passes (30). Another singularity of this study is that the gap distance proved to be more important than the number of passes in terms of the fibre diameter reduction, lignin and hemicellulose reduction, crystallinity and fibrillation. Lignin and hemicellulose, despite having been decreased to 13% and 7–9% respectively during the process, have been observed to enhance fibrillation. Thus, a high degree of fibrillation (yielding micro-fibres of diameter 1–2 µm) was obtained at a relatively low power consumption (4.1 kWh/kg fibre). Finally, a detailed explanatory mechanism based on the literature-reported viscoelasticity of lignin has been given to explain how it facilitates fibrillation. Graphical abstract showing the outcomes of wet grinding of untreated banana fibres. [ABSTRACT FROM AUTHOR]

A heavy metal ion adsorbent (HFPANF) with high surface area was obtained from polyacrylonitrile fibers with fibrillation and alkali hydrolysis, and an activated carbon fiber filter was prepared by using HFPANF as the binder. The surface area of polyacrylonitrile was 48.64 m2/g due to fibrillation, which also led to the carboxyl content of the HFPANF up to 3.4 mmol/g. Batch adsorption experiments on Cu2+ and Pb2+ showed that the adsorption capacities of HFPANF for Cu2+ and Pb2+ were 47.5 mg/g and 54.3 mg/g. The adsorption kinetics showed that the adsorption reached equilibrium at 90 min and that the adsorption followed the pseudo-second order model. It indicates that the adsorption process is chemisorption. HFPANF formed a single tooth chelate with Cu and a double tooth chelate with Pb. HFPANF-ACF filter was prepared by wet molding technique. When the HFPANF content was 30%, the filter reached a compressive strength of 15.37 MPa and its maximum flux was 180 L/h. 2.5 mg/L of Cu and Pb were used for dynamic adsorption experiments and the heavy metal removal rate was still above 95% after filtering 600 L. The pressure drop of HFPANF-ACF filter was much smaller compared with that of GAC filter due to the combined effect of fibrillated nanofibers and ACF, which can improve the filtration efficiency of the filter. [ABSTRACT FROM AUTHOR]

Phenol-soluble modulins (PSMs) are virulent peptides secreted by staphylococci that undergo self-assembly into amyloid fibrils. This study focuses on Staphylococcus aureus PSMα1 and PSMα3, which share homologous sequences but exhibit distinct amyloid fibril structures. Upon subjecting PSMα1 to an 80°C heat shock, it fibrillates into cross-β structures, resulting in the loss of cytotoxic activity. Conversely, PSMα3 cross-α fibrils undergo reversible disaggregation upon heat shock, leading to the recovery of cytotoxicity. The differential thermostability probably arises from the presence of hydrogen bonds along the β-strands within the β-sheets of the cross-β fibrils. We propose that the breakdown of PSMα3 fibrils into soluble species, potentially co-aggregating with membrane lipids, is crucial for its toxic process and enables the reversible modulation of its biological activity under stress conditions. In contrast, the formation of robust and irreversible cross-β fibrils by PSMα1 corresponds to its role in biofilm stability. These findings emphasize how the unique fibril morphologies and thermostability of PSMα1 and PSMα3 shape their functional roles in various environments of S. aureus.

The present study investigates the influence of surface fibrillation of lyocell fibres on the adhesion and resulting properties of short fibre-reinforced polypropylene (PP) and polylactide (PLA) composites. Fibrillation was shown to reduce the tensile strength and elongation at break of the fibres, while not affecting Young's modulus. It was demonstrated that fibrillation improved adhesion significantly compared to non-fibrillated (untreated) fibres, and the critical fibre length determined by microbond tests was reduced. Despite the reduced tensile strength of the fibrillated lyocell fibres, the tensile strength of the composites was increased by a factor of 1.15 for PP and 1.62 for PLA compared to composites produced with untreated fibres. The Young's modulus of the composites was increased using fibrillated fibres by a factor of 1.41 for PP and 1.20 for PLA. The impact strength was also improved by using fibrillated fibres by a factor of 1.38 for PP-based and 1.23 for PLA-based composites. Surface fibrillation of lyocell offers interesting application possibilities, particularly for short fibre-reinforced materials, as the higher specific fibre surface reduces the critical fibre length of lyocell, leading to improved stress transfer from the matrix to the fibre. These fibres seem particularly promising to enhance the mechanical properties of short-fibre reinforced composites for 3D printing applications.

Background: Multiple methods of quantifying social determinants of health exist, such as the social vulnerability index (SVI). We assess the impact of the SVI on atrial fibrillation (AF)‐related cardiovascular disease mortality. Methods: CDC databases were used to obtain mortality and SVI information. Age‐adjusted mortality rates (AAMR) were compared among all US counties, aggregated by SVI quartiles. Results: AAMR was not increased in counties within the highest SVI quartile, consistent across gender and geographic subgroups. Conclusions: Increased SVI is a poor marker to predict mortality outcomes associated with AF. [ABSTRACT FROM AUTHOR]

Dichlorotriazine reactive crosslinker has been used to reduce the fibrillation of Lyocell. The fibrillation propensity and mechanism of 4, 6-dichloro-2-sodium dioxy-1, 3, 5-triazine treatment on Lyocell fibers were studied, and the mechanical properties and dyeing properties of the treated Lyocell fibers were evaluated. The results showed that the three-step reaction process can make lyocell have more uniform behavior of decreased fibrillation propensity, in which the first step is physical mixing of triazine and cellulose, the second and third steps are the stepwise reactions of cellulose with two chlorines of Dichlorotriazine under different conditions, respectively. At the end of the reaction, non-fibrillating Lyocell fibers were produced. In addition, the structure, mechanical properties and dyeing properties of the Lyocell fibers were not affected by the cross-linking chemical reaction process. In conclusion, this study provides a better uniform effect and economically reasonable route for the preparation of commercial non-fibrillating Lyocell fibers.