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Stimuli‐responsive materials have recently gained significant attention in the field of soft robotics, sensors, and biomimetic devices. The most facile way for the fabrication of such materials remains to endow bilayer structures which are fabricated with the combination of active and passive layers. Although, easily fabricated, these structures suffer from the generation of stress points between connection areas. In this work we develop a method to create a thin film with controlled cross‐link variation across its thickness. The cross‐link gradient is achieved through polymerization induced diffusion of dithiol molecules in thiol‐ene network. As a result, the film exhibits bending deformation upon illumination with light or exposure to a chemical solvent, thereby demonstrating dual responsiveness. Light actuation of the film is achieved via photothermal effects due to the incorporation of dye into the system which can absorb UV light and heat the network. While solvent induced actuation is due to anisotropic swelling. Furthermore, the straightforward fabrication procedure allows for the creation of more complex deformations by patterning the film using a photomask during photopolymerization. [ABSTRACT FROM AUTHOR]

Surgical sutures are gold‐standard wound closure devices. However, they are unable to form a tight seal with surrounding tissues, raising the risks of body fluid leakage and surgical site infection. Additionally, the use of sutures can result in cracking at suture roots, damage and micro‐trauma to soft tissues due to the slicing and compression of suture fibers after their placement. Bioadhesives capable of mimicking natural biological interfaces are appealing alternatives, but they cannot achieve the same level of strength as conventional surgical sutures. Here, a tough adhesive puncture sealing (TAPS) suture, featuring swelling‐triggered bioadhesion to mend the gap between the suture and the surrounding tissues with a soft yet tough adhesive interface is reported. This unique design principle of TAPS sutures is applicable to diverse soft tissues of various defect sizes and can be controlled by modulating the hydrogel swelling kinetics. The advantages of the TAPS sutures for meniscal tear repair and intestine tissue sealing ex vivo, corroborates their favorable applications in managing mechanically active musculoskeletal and gastrointestinal tissues are demonstrated. The design and performance of the TAPS sutures offer extensive possibilities for redesigning surgical tools and developing next‐generation medical devices for wound management and tissue repair. [ABSTRACT FROM AUTHOR]

Large scale computer simulations are employed to analyze the conformations of network strands in polymer networks at preparation conditions (characterized by a polymer volume fraction of ϕ0) and when swollen to equilibrium (characterized by a polymer volume fraction ϕ < ϕ0). Network strands in end‐linked model networks are weakly stretched and partially swollen at preparation conditions as compared to linear polymers in the same solvent at ϕ0. Equilibrium swelling causes non‐ideal chain conformations characterized by an effective scaling exponent approaching 7/10 on intermediate length scales for increasing overlap of the chains. The chain size in a network consists of a fluctuating and a time average "elastic" contribution. The elastic contribution swells essentially affinely ∝(ϕ0/ϕ)2/3, whereas the swelling of the fluctuating part lies between the expected swelling of the entanglement constraints and the swelling of non‐cross‐linked chains in a comparable semi‐dilute solution. The total swelling of chain size results from the changes of both fluctuating and non‐fluctuating contributions. [ABSTRACT FROM AUTHOR]

Hydrogels based on sodium alginate (SA) and partially neutralised poly(acrylic acid) were obtained by radical polymerisation. The hydrogels were cross-linked with N,N′-methylenebisacrylamide (MBA), simultaneously grafting the resulting polymer onto SA. The findings of the FTIR spectroscopy showed that all of the hydrogels were effectively synthesized and sodium alginate was chemically bonded with the poly(sodium acrylate) matrix. DSC analysis of the melting heat and glass transition parameters indicated that the hydrogel structure had changed as a result of the cross-linking process. Sodium alginate and MBA were tested at different concentrations to determine how they affected the hydrogel properties. A very high content of the biopolymer, i.e., sodium alginate, was used in our research, up to 33 wt%. This resulted in durable and stable hydrogels with a very high ability to uptake water, comparable to hydrogels based on synthetic polymers only. The ability to swell is inversely proportional to the quantity of MBA present. By increasing the amount of sodium alginate in the hydrogel, the ability of the hydrogel to absorb water is reduced. However, water uptake remains relatively high at 350 g·g−1, even for the hydrogel with the highest SA content. [ABSTRACT FROM AUTHOR]

Deuterium-tritium fusion reactions produce energy in the form of 14.1 MeV neutrons, and hence fusion reactor components will be exposed to high energy neutron irradiation while also being subjected to thermal, mechanical and magnetic loads. Exposure to neutron irradiation has numerous consequences, including swelling and dimensional changes, comparable in magnitude to the peak transient thermal deformations occurring in plasma-facing components. Irradiation also dynamically alters the various thermo-mechanical properties, relating temperature, stress and swelling in a strongly non-linear way. Experimental data on the effect of neutron exposure spanning the design parameter space are very sparse and this highlights the relevance of computer simulations. In this study we explore the equivalence between the body force/surface traction approach and the eigenstrain formalism for treating anisotropic irradiation-induced swelling. We find that both commercial and massively parallelised open source software for finite element method (FEM) simulations are suitable for assessing the effect of neutron exposure on the mechanically loaded reactor components. We demonstrate how two primary effects of irradiation, radiation swelling and the degradation of thermal conductivity, affect the distributions of stress and temperature in the divertor of the ITER tokamak. Significant uncertainties characterising the magnitude of swelling and models for treating it suggest that on the basis of the presently available data, only an order of magnitude estimate can be given to the stress developing in reactor components most exposed to irradiation during service. [ABSTRACT FROM AUTHOR]

When calcium-based stabilizers (e.g., lime and cement) are used to treat sulfate-bearing soil, ettringite will be produced under wet conditions, causing swelling of the soil and damage to pavements constructed on sulfate-bearing soils. In order to reduce the swelling of soils caused by ettringite, this study attempted to use the non-calcium-based activators (sodium silicate and NaOH) to activate ground granulated blast-furnace slag (GGBS) to stabilize the sulfate-bearing soil. A series of experiments were carried out: unconfined compression strength, swelling test, leaching test, X-ray diffraction (XRD), and scanning electron microscopy (SEM) tests, to study the performance of soils treated with sodium silicate–NaOH-GGBS. The results showed that the swelling percentage of sodium silicate–NaOH-GGBS-treated soils (0–0.2%) were smaller than that of cement-treated soil (1.2%), and their strengths (1.35–3.35 MPa) were higher than cement-treated soil (0.79 MPa). This was attributed to the formation of ettringite in the cement-stabilized soil after soaking. The calcium ion (Ca2+) concentration in the cement-stabilized soil was higher than that in the sodium silicate–NaOH-GGBS-stabilized soils, and the Ca2+ concentration in the sodium silicate–NaOH-GGBS-stabilized soils kept at a low and stable level. The rapid consumption of Ca2+ in sodium silicate–NaOH-GGBS-stabilized soils for the synthesis of calcium silicate hydrate (CSH) caused the absence of Ca2+ and prevented the production of ettringite. XRD and SEM tests did not detect ettringite in the sodium silicate–NaOH-GGBS-treated soils, which was the reason for insignificant swelling and high strength of the soils. Overall, the sodium silicate–NaOH-GGBS were effective in suppressing swelling due to ettringite and enhancing the strength of sulfate-bearing soils. [ABSTRACT FROM AUTHOR]

Five randomly cross-linked amphiphilic copolymer networks (ACPN) were prepared via the free radical cross-linking copolymerization of the hydrophobic n-butyl acrylate (BuA) and the hydrophilic N,N-dimethylacrylamide (DMAAm), in the presence of a small amount (5 mol% with respect to the sum of BuA plus DMAAm monomers) of the hydrophobic 1,6-hexanediol diacrylate (HexDA) cross-linker, initiated by 4,4ʹ-azobis(4-cyanovaleric acid) in 1,4-dioxane at a 10 % w/v total monomer concentration. The five ACPNs differed in their BuA content, fixed at 10, 30, 50, 70 and 90 mol%. The two homopolymer networks, BuA and DMAAm, were also prepared using the same polymerization method. Thus, this study involved a total of seven polymer networks, forming a homologous series with BuA contents ranging from 0 to 100 mol%. These networks were characterized in terms of their degrees of swelling in tetrahydrofuran (THF) and water, their mechanical properties in water, and their adhesion to human skin. The degrees of swelling (DS) of the networks in THF were higher than those in water because THF is a non-selective solvent, whereas water is selective for the hydrophilic DMAAm units. The DSs in THF increased with the network content in the less polar BuA units, while the opposite was true for the DSs in water which decreased with the content in the hydrophobic BuA units from 11 (0 mol% BuA) down to 1.1 (100 mol% BuA). A maximum in the elastic modulus was observed for the hydrogel with 50 mol% BuA, reflecting the opposing effects of polymer composition in soft polymer (polyBuA) content and hydrogel water content. In contrast, the tensile strain at break increased monotonically with the hydrogel BuA content, reaching a remarkable ∼900 % for the hydrogel with 90 mol% BuA. Finally, the adhesion of the ACPNs, both in their dried and hydrated states, onto human skin was explored. The adhesion of the hydrated samples onto skin was stronger than that of the dried ones. The hydrated ACPN with 30 mol% BuA exhibited the strongest adhesion onto skin, attributable to the best combination of a rather high content in polar DMAAm units (70 mol%), and a rather low aqueous DS (∼2.5), with the low DS value causing only a small dilution in the DMAAm units participating in the polar interactions with skin. The present work demonstrates that, even in this synthetically simple ACPN system, the multiple effects of ACPN composition on a certain property, in some cases opposing and in some other cooperating, lead to a rather complicated behavior. In particular, as the BuA content increases, some properties display maxima (elastic modulus, stress at break and fracture energy of hydrated ACPNs, and adhesion of hydrated ACPNs onto skin) while some other properties exhibit monotonic increases (strain at break of hydrated ACPNs, and adhesion of dried ACPNs onto skin). Thus, the optimal ACPN for a particular application will highly depend on the property best-serving the particular application, e.g., the ACPNs with 30, 50 and 90 mol% BuA for strongest wet adhesion to skin, stiffest hydrogel response, and highest hydrogel extensibility and toughness, respectively. [ABSTRACT FROM AUTHOR]

Liquid silicone rubber (LSR) garners attention across a diverse range of industries owing to its commendable fluidity and heat resistance. Nonetheless, its mechanical strength and oil resistance fall short compared to other rubbers, necessitating enhancement through the incorporation of a suitable filler. This research focuses on reinforcing LSR using carbon black (CB) particles as a filler, evaluating the mechanical properties and oil resistance of neat LSR, and LSR containing up to 3 wt% of CB filler. CB was added in powder form to investigate its effect on LSR. When LSR was impregnated with oil, the deterioration of rubber was noticeably observed under high-temperature conditions compared to room-temperature conditions. Consequently, the mechanical properties and oil resistance, excluding the permanent compression reduction rate, tended to increase as the filling content of CB increased compared to the unfilled state. Notably, in the specimen with 2 wt% CB filler, the tensile modulus increased significantly by 48% and the deterioration rate was reduced by about 50% under accelerated deterioration conditions. Additionally, the swelling rate in oil decreased by around 14%. This validates a notable improvement in both mechanical properties and oil resistance. Based on the identified mechanism for properties enhancement in this study, CB/LSR composite is expected to have a wide range of applications in fields such as gaskets, oil seals, and flexible sensors. [ABSTRACT FROM AUTHOR]

AbstractMolybdenum disulfide (MoS2), a two-dimensional inorganic molecule, has lately been studied in medical research with regard to carrying pharmaceuticals due to its distinctive characteristics. A biodegradable polymer system applicable in cancer drug delivery can be created with the addition of MoS2. In our research described in this paper, we investigated the influence of the amount of MoS2 on the characteristics and performance of our novel gel blend. It was aimed to prepare a new gel blend, which we thought would have the potential to be used as a stimulus-sensitive, polymeric hydrogel as a carrier in the triple negative breast cancer (TNBC) drug delivery system, with the MoS2 added to the polyethylene glycol (PEG)/κ-carrageenan combination. This 2D material (MoS2) impacted the hydrogel by improving the transmittance, swelling, and elasticity performance compared to the normal no MoS2 structure of the polymeric gel. The polymer blend characteristics were mainly tested using UV-VIS spectrophotometry and gravimetric analysis. The varied properties of these gel mixtures were investigated using five different mass ratios of MoS2. The 5 mg MoS2/(PEG)/κ-carrageenan gel was the best sample investigated in terms of the elasticity. The results of the study demonstrated that our gel system can be utilized for precisely targeted and regulated delivery of cancer drugs. To create preliminary data for this near future goal, the release mechanism of the Doxorubicin drug loaded into the produced gel were examined. [ABSTRACT FROM AUTHOR]

In a growing world population scenario, greater demand for food and in turn agricultural input is expected in the coming decades. The development of innovative sustainable amendments and fertilizers such as hydrogels (HGs) relies on this context. HGs are defined as 3D polymeric networks with the ability to absorb and retain a large amount of water (i.e., swellability). HGs swellability makes them ideal platforms for water- and nutrient-controlled release. The literature reflects a notable diversity in HGs composition, properties, and impacts on agroecosystems, resulting in the dissemination of information across multiple publications. Within this context, the primary aim of this scientific review is to systematically compile, critically evaluate, and synthesize the latest findings and relevant literature pertaining to the application of HGs in agroecosystems. We found that this class of materials was consistently found on soil bulk density, crop available water, soil electrical conductivity, cation exchange capacity and main cereal or legume crops performances particularly under moderate water deficit conditions, suggesting their effectiveness for arid and semi- arid areas. Encouraging results were also found on pesticide, agrochemicals, and microorganisms delivering. Thus, the delivery of agronomic inputs with loaded-HG may play a key role in forthcoming agriculture that would minimize the agronomic impact on the environment. Nevertheless, some critical issues still remain open, concerning: (i) the decreased of HG effectiveness following wetting and drying cycles, (ii) the impact of Na+ contained in HG on crop cells, (iii) the HG effect on soil saturated hydraulic conductivity and pH, and (iv) HG biodegradability and their fate into the environment. In conclusion, HGs seem a promising technology to reach/maintain food security and soil health, but future research should address the development of well-defined protocols for producing biowaste-derived HG that will ensure their biodegradability and non-toxicity and will disclose new insights into a circular economy approach agronomy. One of the biggest challenges would be the synthesis of “smart” HG able to respond to environmental stimuli triggering molecule(s) release in soil. [ABSTRACT FROM AUTHOR]

Sorbents are promising materials for applications in atmospheric water harvesting, thermal energy storage, and passive cooling, thereby addressing central challenges related to water scarcity and the global energy transition. Recently, hygroscopic hydrogel composites have emerged as high‐performance sorbents. However, many of these systems are fabricated with unsustainable and costly sorbent materials, which hinders their wide deployment. Here, the synthesis of high‐performance, cost‐efficient polyacrylamide hydrogels loaded with unprecedented amounts of calcium chloride is demonstrated. To this end, the swelling procedure of polyacrylamide hydrogels in aqueous calcium chloride solutions is optimized. The achievable salt loading in the hydrogel is characterized as a function of temperature, calcium chloride concentration in the swelling solution, and the hydrogel preparation conditions. The obtained hydrogel‐salt composites are shown to be stable under repeated sorption‐desorption cycling and enable water uptakes of 0.92 and 2.38 grams of water per gram of dry materials at 30% and 70% relative humidity, respectively. The resulting cost‐performance ratio substantially exceeds lithium chloride‐based systems. Further, the mechanistic insights on hydrogel salt interactions can guide the design of sustainable and low‐cost sorbent materials for future applications in water and energy. [ABSTRACT FROM AUTHOR]

Amphiphilic polymer gels show environmentally sensitive mechanical properties depending on the solvent polarity, which makes them useful for applications in soft contact lenses, membranes, drug delivery systems, and tissue engineering. To rationally design the material properties for such applications, a sound knowledge about the mechanical properties at different solvency states is necessary. To acquire such knowledge, amphiphilic networks are prepared by hetero‐complementary coupling of amine‐terminated tetra‐poly(ethylene glycol) (t‐PEG‐NH2) with 2‐(4‐nitrophenyl)‐benzoxazinone terminated tetra‐poly(ε‐caprolactone) (t‐PCL‐Ox). The mechanical properties are investigated on different length‐scales and under non‐selective and selective solvent conditions using shear rheometry and atomic force microscopy (AFM). The swelling as well as the modulus in good solvent are in accord with scaling laws found for other four‐arm star‐shaped polymer networks and theoretical predictions. The swelling in selective solvent reveals a concentration‐independent volume swelling degree and a nearly linear scaling of the modulus with concentration. The surface topography probed by AFM reveals microphase‐separated structures in the range of 20 nm. Similar modulus values are obtained for bulk films in water using the complementary methods of atomic force microscopy and rheometry. The data are compared with pure hydrophilic networks to identify the effect of amphiphilicity on the material properties. [ABSTRACT FROM AUTHOR]

AbstractVanadium is a typical low-activation metal and has the advantages of lower neutron irradiation activation, better mechanical properties at high temperature, and higher compatibility with the liquid lithium blanket. However, the effect of helium on the formation of irradiation defects in vanadium has not been adequately explored at low temperatures (below 723 K). Helium ion irradiations of 18 keV up to 0.54 displacement per atom were employed to study the temperature-dependent behavior of irradiation defects in vanadium at 523, 623, and 723 K. Helium bubbles were observed in vanadium under irradiations at all temperatures, but no dislocation loops were observed. With the increase of irradiation temperature, the average size of helium bubbles and swelling increased, and the density of helium bubbles decreased. It is noteworthy that the average size of helium bubbles and swelling increased significantly when the irradiation temperature increased from 623  to 723 K. In addition, pentagonal helium bubbles, helium bubbles nucleated at the grain boundary, and combinations between helium bubbles were observed. [ABSTRACT FROM AUTHOR]

Pressure‐induced swelling has been reported earlier for several hydrophilic layered materials. MXene Ti3C2Tx is also a hydrophilic layered material composed by 2D sheets but so far pressure‐induced swelling is reported for this material only under conditions of shear stress at MPa pressures. Here, high‐pressure experiments are performed with MXenes prepared by two methods known to provide "clay‐like" materials. MXene synthesized by etching MAX phase with HCl+LiF demonstrates the effect of pressure‐induced swelling at 0.2 GPa with the insertion of additional water layer. The transition is incomplete with two swollen phases (ambient with d(001) = 16.7Å and pressure‐induced with d(001) = 19.2Å at 0.2 GPa) co‐existing up to the pressure point of water solidification. Therefore, the swelling transition corresponds to change from two‐layer water intercalation (2L‐phase) to a never previously observed three‐layer water intercalation (3L‐phase) of MXene. Experiments with MXene prepared by LiCl+HF etching have not revealed pressure‐induced swelling in liquid water. Both MXenes also show no anomalous compressibility in liquid methanol. The presence of pressure‐induced swelling only in one of the MXenes indicates that the HCl+LiF synthesis method is likely to result in higher abundance of hydrophilic functional groups terminating 2D titanium carbide. [ABSTRACT FROM AUTHOR]

Rainfall infiltration softens the filling material of deep cracks in expansive soil, significantly reducing its mechanical strength and causing slope instability and failure. Investigating this influence is crucial for preventing slope disasters. This study established a model with a weak interlayer to conduct rainfall infiltration tests on an expansive soil slope. Analyzing the moisture absorption and deformation model test results, the study delved into the temporal and spatial variations of the slope’s seepage field. It also clarified the evolution characteristics and action modes of the strain field under seepage influence. Results indicate that runoff leads to pooling at the slope foot, causing significant softening and swelling. The seepage and deformation fields exhibit a “start-rapid growth-slow growth-tend to stability” pattern on the time curve. Soil affected by rainfall infiltration is concentrated at depths of 10–20 cm. The start-up stage of deep soil displacement change is primarily due to water infiltration delay, intensifying with depth. The weak interlayer weakens and is destroyed after moisture absorption, resulting in the upper slope losing support force, leading to continued collapse and slope failure. The research provides a systematic understanding of the mechanism and failure mode of slope disasters, verifying and analyzing permeability, swelling, shrinking, and seepage characteristics of expansive soil. [ABSTRACT FROM AUTHOR]

This study deals with preparing and characterizing polyvinyl alcohol/egg white/montmorillonite bionanocomposite hydrogels as antibacterial drug delivery systems. The cyclic freezing/thawing method was utilized to fabricate the hydrogels. To study the performance of the prepared hydrogels as drug delivery systems, amoxicillin, as a model antibiotic drug, was loaded into the hydrogels by mixing with the precursor polymer solution and gelation. From the diverse microstructural characterization techniques, i.e. XRD, SEM, AFM, DLS, and gel fraction estimation, it was possible to infer that montmorillonite has been successfully incorporated into the hydrogel network and acted as an additional crosslinker to bind the chains of egg white and polyvinyl alcohol. Scrutinizing the physical properties of the produced hydrogels demonstrated that increasing incorporated montmorillonite content adversely affects the prepared hydrogels' swelling ability and prolongs their dehydration period. Additionally, the Swelling characteristics of the hydrogels were evaluated at different pHs. Results showed an increase in the swelling ability of all samples by raising the pH value of the medium. Additionally, it was proved that both swelling and dehydration of the hydrogels follow non-Fickian diffusion. In vitro drug delivery experiments demonstrated that the cumulative fractional release of amoxicillin was adversely dependent on the amount of incorporated montmorillonite into the hydrogels and positively dependent on the pH of the release solution. It was also found that, in all examined samples, the mechanism by which the release of clindamycin happens is non-Fickian or anomalous transport. [ABSTRACT FROM AUTHOR]

Polymer matrix tablets are an important drug-delivery system widely used for oral drug administration. Understanding the tablet hydration process, both experimentally and theoretically, is, thus, very important for the development of drug delivery systems that exhibit high drug loading capacity and controlled release potential. In this study, we used magnetic resonance microscopy (MRM) to nondestructively and dynamically analyze the water hydration process of xanthan-based tablets. The swelling process was characterized by well-resolved fronts of erosion, swelling, and penetration. The experimental results were complemented by numerical simulations of the polymer matrix hydration process. In the simulations, the polymer tablet matrix was modeled as an assembly of interacting chains with embedded drug particles, while its hydration process was mediated by interaction with solvent particles. The swelling dynamics were modeled within a Monte Carlo-based bond fluctuation model (BFM) that elegantly accounted for steric and nearest-neighbor interactions. This study provides an efficient experimental–theoretical approach for the study of polymer matrix swelling processes. [ABSTRACT FROM AUTHOR]

Water plays an important role in the properties of cellulose. In materials design, the water uptake of cellulose has been traditionally seen as a drawback, since water reduces mechanical resistance of paper and cardboard, and at high hydration, cellulose-based products are disintegrated. However, recently, the hydration of cellulose has been considered as an advantage to design water-responsive soft actuators. In Nature, water is the fuel for several plant functions that involve motion, such as the seed release or the plant protection from high temperature and radiation. Inspired by these natural systems, cellulose-based actuators have been designed to display different movements (bending, twisting, curling) in response to water. Biopolymer structuration inducing anisotropy within the system allows the asymmetric expansion of layers, which results in macroscopic movement. This review gives an overview of the soft actuators triggered by the hydration/dehydration processes of cellulose. We present representative examples of water-triggered natural actuators, which have inspired researchers to design anisotropic cellulose-based materials that develop controlled movement in response to water. [ABSTRACT FROM AUTHOR]

Legumes are a cost-effective source of proteins and abundant starch, a biodegradable substance, providing human nutrition and serving various food sectors globally. Some of the neglected (underutilised) legumes can also be used as the cheapest source of starch. Therefore, the present study was conducted to determine the physicochemical characteristics of jack bean (Canavalia ensiformis) starch - a legume not widely known so underutilised. The starch was isolated from the bean by standard method to study its various properties. One-way analysis of variance was employed to verify a significant difference at the 5% significance level. The jack bean yielded 30.98% of starch. The starch's moisture, ash, fat, protein, fiber, and carbohydrate content were 9.67%, 0.19%, 0.27%, 0.56%, 0.27%, and 89.28% respectively. The physicochemical properties were also determined. The apparent and total amylose contents were 43.82% and 47.78%, respectively, with 7.66% of amylose leaching at 95° C. The water and oil absorption capacities were 2.31 and 2.56 g/g, respectively, while emulsion capacity and stability were 62.30 and 71.38 %, respectively. The solubility and swelling power of jack bean starch increased with temperature from 55 to 95°C. The effect of starch concentrations (6, 8, and 10%) on freeze-thaw stability revealed that water expelled decreased as starch content increased. Nevertheless, a comprehensive investigation has not been conducted into the distinct functional characteristics and other attributes of jack bean starch. This study could provide new opportunities for conventional starch industries that rely on starch from sources like cereals, tubers, and rhizomes. [ABSTRACT FROM AUTHOR]

Wood waste, which constitutes an important component of solid waste, is produced by the wood industry, and especially in the processing one. The wood industry includes tree bark, sawdust, planer shavings, sander dust etc. produces unwanted products and/or wastes. This study investigated the usability of sawdust of fruit trees in the production of Medium Density Fiberboard (MDF) and some technological properties of the produced MDF panels. Sawdust of fruit trees was mixed to beech fibers at the ratio of 10, 20 and 30% by weight. The mats were manually formed using 13% urea formaldehyde and pressed at a temperature of 185°C for 8 min in a computer control press. The MDF panel samples of water absorption (WA), thickness swelling (TS), surface hardness, surface roughness, MOR and MOE were investigated. It was determined that the values of WA and TS decreased with increasing the ratio of sawdust. Modulus of rupture (MOR), modulus of elasticity (MOE), surface hardness, surface roughness parameters (Ra, Rq and Rz) values of panel samples increased with increasing the ratio of sawdust from panels. Based on these results, it is advisable that wood sawdust fruit-trees can be used as an alternative raw material source in MDF production. [ABSTRACT FROM AUTHOR]

We conducted an experimental study on the swelling–shrinking characteristic of expansive soil treated with enzyme-induced carbonate precipitation (EICP) using yellow soybean. A series of tests including the free swell test, swelling rate test, swelling pressure test, and shrinking test were conducted on expansive soil specimens with various water contents and equimolar concentrations. The test results showed that EICP-treated expansive soil samples exhibited an obvious reduction in the magnitude of free swelling rate, swelling rate, swelling pressure, and shirking rate compared with the untreated one. This indicates that EICP using yellow soybean can effectively reduce the swell and shrink potential of expansive soil. The free swelling rate consistently decreases with the increasing equimolar concentration. A more remarkable reduction in swelling rate can be observed at a concentration of 1 mol/L compared with a less significant decrease at a higher concentration. The free swelling rate shows an ascending trend first and then a declining tendency with the increase of water content at higher equimolar concentrations. The influences of equimolar concentration and water content on the change of swelling rate for treated samples with applied loading pressures are insignificant. The swelling pressure reduces remarkably with increasing equimolar concentration and then tends to level off. The swelling pressure exhibits an ascending tendency with the increase of water content. The shrinking rate reduces more remarkably with equimolar concentration at first and then increases less remarkably, with an equimolar concentration of 2 mol/L exhibiting the lowest shrinking rate. The soil specimen with higher water content shows a higher value of shrinking rate than that with a lower one. [ABSTRACT FROM AUTHOR]

The swelling properties of polyacrylonitrile gel prepared by the repeating cycle of freezing and thawing were examined, as its transient response toward the equilibrium swollen states varies with the variation of mixing ratio (r) of the immersion solvent which consisted of N, N–dimethylacetamide and benzene. Two experimental protocols were used; successive solvent exchanges were conducted in Protocol 1, and no solvent exchange but the varying of the volume of immersion solvent was conducted in Protocol 2. Also, the aging time was set between the end of the freezing and thawing cycle and the start of the swelling experiment. As a result, the equilibrium swelling ratio decreased with the increase in the aging time. Significant discrepancies for the transient responses were found for the immersion solvents between r ≤ 0.74 and r ≥ 0.78 both in Protocol 1 and 2, in which the elution of polyacrylonitrile molecules was related to the responses. A characteristic overshoot curve was observed in the swelling with r ≥ 0.78 in Protocol 2, which was also attributed to the polyacrylonitrile elution. The polymer solvent interaction parameter was calculated on the basis of the osmotic pressure equilibrium, which was associated with the interpretation of the transient response data. [ABSTRACT FROM AUTHOR]

Background: Anterior cervical discectomy and fusion is the most commonly used surgical approach for treating cervical spine conditions, but it can often lead to postoperative swallowing difficulties. To retrospectively assess the effects of topical triamcinolone acetonide in the anterior cervical surgery on swallowing function. Methods: In this study, a retrospective design was used to select patients aged 18 years and older who were diagnosed with cervical spondylosis and required anterior cervical discectomy and fusion. Among them, the patients in the experimental group used triamcinolone acetonide topically in front of the plate during surgery, and the control group was the patients who did not use triamcinolone acetonide. The sex, age, operation time, operation segment, and preoperative soft tissue area were compared between the two groups. Results: There were no significant differences in gender, age, operation time, and segment between the two groups. For the preoperative soft tissue area, triamcinolone acetonide was significantly lower than in the control group (P < 0.05). Conclusion: The retrospective results of this study support that topical triamcinolone acetonide as a treatment in anterior cervical surgery can significantly reduce soft tissue swelling, and no effect was found on the operation time, postoperative blood loss, and segment. These findings provide an important basis for clinical care teams to make treatment decisions and confirm the effectiveness of triamcinolone acetonide in improving swallowing function. However, there was a possibility of information collection and selection bias due to the limitations of retrospective studies. To confirm and further advance the use of this treatment, more rigorous prospective randomized controlled trials are recommended to validate these preliminary results. [ABSTRACT FROM AUTHOR]

A 58-year-old man with a history of diabetes type I and chronic coronary syndrome who underwent coronary artery bypass grafting (CABG) 7 years before was admitted to a cardiology unit for unplanned cardiac catheterization because of dyspnea and chest pain at rest. Femoral access was chosen because of the previous CABG and a vascular closure device (VCD) was used at the end of the procedure. Because of femoral artery rupture during VCD implantation, surgical vascular repair was performed. About 45 days later, the patient experienced a growing inguinal swelling at the site of vascular access in the absence of fever and clinical features of inflammation. The swelling became painful over time. Despite the most probable hypothesis of a hematoma, pseudoaneurysm, and inguinal abscess, a final diagnosis of lymphocele was made. [ABSTRACT FROM AUTHOR]

Brain edema is considered as a common feature associated with hepatic encephalopathy (HE). However, its central role as cause or consequence of HE and its implication in the development of the neurological alterations linked to HE are still under debate. It is now well accepted that type A and type C HE are biologically and clinically different, leading to different manifestations of brain edema. As a result, the findings on brain edema/swelling in type C HE are variable and sometimes controversial. In the light of the changing natural history of liver disease, better description of the clinical trajectory of cirrhosis and understanding of molecular mechanisms of HE, and the role of brain edema as a central component in the pathogenesis of HE is revisited in the current review. Furthermore, this review highlights the main techniques to measure brain edema and their advantages/disadvantages together with an in-depth description of the main ex-vivo/in-vivo findings using cell cultures, animal models and humans with HE. These findings are instrumental in elucidating the role of brain edema in HE and also in designing new multimodal studies by performing in-vivo combined with ex-vivo experiments for a better characterization of brain edema longitudinally and of its role in HE, especially in type C HE where water content changes are small. [ABSTRACT FROM AUTHOR]

Background: After total knee arthroplasty (TKA), patients have limited knee range of motion (ROM), trophic changes and pain. Cryotherapy and compression are recommended in the literature, but no study has shown that cryotherapy and compression combined leads to better results than cryotherapy alone. The primary objective was to compare knee ROM after 21 days of rehabilitation post-TKA between patients who underwent rehabilitation with compressive cryotherapy with those who had cryotherapy alone. The secondary objectives were to compare other trophic, pain and functional outcomes. Methods: Forty patients were randomized into two groups: Standard Cryotherapy (SC = 20, median age 77 years), which applied cold packs along with their rehabilitation; and Compressive Cryotherapy (CC = 20, median age 76 years), which received cold compression. Knee joint's passive and active ROM (primary outcome) were measured with a goniometer. Knee's circumference, fluctuation test, pain at rest and during activity, 6-minute walking test (6MWT) and KOOS questionnaire were secondary outcomes. The groups were compared on D1 (baseline) and D21 of rehabilitation. A survival analysis has compared the groups on D1, D8, D15, D21. Results: All subjects had a significant improvement in all the parameters on D21 relative to D1 (p <.05), except for pain at rest (p =.065 for CC and p =.052 for SC). On D21, the CC group had a significantly larger improvement in the joint effusion (p =.002), pain during activity (p =.005), 6MWT (p =.018) and KOOS (p =.004) than the SC group. Based on the survival analysis, the CC group had significantly faster improvement in the joint ROM (p =.011 for flexion and p =.038 for extension) and knee circumference (p =.013) than the SC group. Conclusions: Both cryotherapy methods improved joint ROM, trophic changes, pain and function. Adding dynamic compression to a cryotherapy protocol provided further benefits: a significantly faster improvement in passive knee flexion ROM, a greater reduction of swelling, and pain during activity. Similarly, walking distance and KOOS questionnaire were significantly better for CC. Trials registration: The study was registered in the ClinicalTrials.gov database on 14/09/2023 (identifier: NCT06037824). [ABSTRACT FROM AUTHOR]

Superabsorbent composites (SC) can be defined as filler-enriched absorbent polymer chemistry. The superabsorbent polymers are made up of hydrophilic polymers with added cross-linking systems and tend to absorb, swell and retain a substantial volume of water. The conventional chemistries are based on synthetic polymers mainly acrylics. Concerning the fossil fuel crisis, their price depletion and to make the superabsorbent compounds more eco-friendly various biobased materials are incorporated into the structure to make the systems eco-friendlier and more sustainable. The biobased compounds widely explored in such areas are starch, cellulose, guar gum, xanthan gum, alginate, etc. The filler namely various clays such as montmorillonite (MMT), Attapulgite (APT), Kaolin, and bentonite in carbon-based fillers carbon nanotubes (CNT), graphite oxide, and various biobased compounds such as proteins, and biobased waste such as wheat straw, rice husk ash, and miscellaneous fillers as semi-coke, layered double hydroxides are well studied in the SC area. The performance of SC depends upon various reaction parameters such as monomers, initiator, modifier, filler, temperature, and time as well on other factors such as pH of the medium and particle size. The SC is found in a variety of application areas such as drug delivery, agriculture, wastewater treatment, the construction industry, sanitary napkins and diapers, food preservation, and artificial snow. [ABSTRACT FROM AUTHOR]

Background: Tourniquet use during upper extremity surgery in patients with a history of axillary lymph node dissection (ALND) remains controversial due to the perceived but unproven risk of lymphoedema. We prospectively evaluated upper extremity swelling in patients with a history of unilateral ALND using a standardised tourniquet model. Methods: A tourniquet was applied to the upper arm bilaterally, with the unaffected side serving as an internal control. Each arm was subsequently held in an elevated position to reduce swelling. Hand volume was measured using an aqueous volumeter. Results: The patients' ALND arms experienced slightly greater increases in volume following tourniquet application compared to their healthy control arms. However, this amount of oedema was temporary and reversible, as both arms experienced spontaneous resolution of swelling with no significant difference in residual hand volume at the conclusion of the study. Conclusions: Tourniquet use may be safe in patients with a history of ALND. Further investigation is needed to verify this in a surgical setting. Level of Evidence: Level II (Therapeutic) [ABSTRACT FROM AUTHOR]

Three small-scale mock-up tests were carried out on artificially fractured Opalinus Clay samples from the lower sandy facies of Mont Terri site: the first with the synthetic water of neutral pH and at an osmotic suction of 1 MPa, the second with a highly NaNO3 saline solution with a neutral pH and at osmotic suction of 34 MPa, and the third with a hyperalkaline solution at pH = 13.5 and at osmotic suction of 1.16 MPa. The radial swelling pressure was monitored using a total pressure sensor along with the fracture opening using a displacement transducer. The tests ran for over 290 days. After that, the three tests were dismantled. A detailed petrophysical characterization of 45 subsamples was conducted, and the pore size distribution was determined at different positions. X-ray diffractometry measurements were also conducted to identify any mineralogical changes. Results show that, in the case of the synthetic water and the alkaline solution, the friction forces exerted by the lid and the base on the sample were significant and probably hampered the self-sealing of the fracture. Saline solutions affect the self-sealing process of claystones. Indeed, even though increasing the salinity caused the contraction of the diffuse double layer and generated additional fractures within the sample, which increased the permeability and thus accelerated the hydration process, a complete self-sealing of the fracture opening was not observed. [ABSTRACT FROM AUTHOR]

The resistance of rubber materials to different solvents and compression set need to be studied in order to determine the proper conditions of use and storage. In this research, we will study the effect of nanographene oxide (GO) as a filler substitution on the swelling characteristics and compression set of ethylene-propylene-diene monomer (EPDM) rubber/styrene-butadiene rubber (SBR) composites. The nanographene oxide was varied based on the amount (0, 2, 4, 6, 8 and 10 phr with and without modification). The EPDM/SBR composites were made using a two-roll mill and vulcanized using a hydraulic press. Furthermore, the composites were tested for resistance to immersion (swelling) according to ASTM D-471 using aromatic, aliphatic, and chlorinated solvents. The compression set testing is carried out according to ASTM D-395 with a compression test apparatus. From the research it is known that modified GO (mGO) can be a suitable filler substitution for EPDM/SBR composites. The 10 phr mGO is the most suitable filler substitution to increase swelling resistance and compression set for EPDM/SBR composites. [ABSTRACT FROM AUTHOR]

Rain-induced shallow failures in expansive soils often occur on gentle slopes with slope ratios of 1:2–1:6, resulting in highly complex stability issuesThis study established an equivalent theoretical model for the swelling behavior of expansive soils based on the similarity theory of temperature and humidity fields. A numerical simulation approach was developed using a model with consistent nodes and the conversion of seepage results and swelling loads, allowing for the decoupling analysis of slope seepage–deformation–stress considering swelling and strength softening. Numerical analyses were conducted on a specific slope profile in a case study, analyzing the distribution and evolution of the slope seepage, deformation, and shear stress. The findings revealed that changes in moisture content at the slope toe have the most significant impact, with infiltration depth and strength attenuation being the largest. Horizontal and vertical deformations were also highly influenced by the reduction of shear strength. The uneven water absorption and swelling of expansive soil slopes resulted in shear stress concentration areas on the slope, leading to local failures near the slope toe and eventual overall instability of the slope. This study provides valuable insights into the complex behavior of shallow failures in expansive soil slopes. [ABSTRACT FROM AUTHOR]

AbstractKaral soils mainly composed of swelling clays are considered as one of the main causes of degradation in civil engineering structures in Cameroon. Thus, a better knowledge on Karal-type soil behavior is required to adapt soil treatment for road construction and foundation dimensioning. The physicochemical, mineralogical and geotechnical characterization of ten soils collected in North and Far North Cameroon allowed to classify Karal among plastic soils. As expected, the optimum water contents and maximum dry densities of dynamically compacted Karal reflected the particle size distribution and the mineralogical soil composition with various amounts of swelling clay (montmorillonite) and quartz associated to sand and silt fractions. Then the swelling/shrinkage properties of compacted specimens evaluated by free swelling test and volume shrinkage test were correlated to soil characteristics to propose a suitable classification for Karal-type soils. Not only swelling but also shrinkage properties were assessed and combined to define a new parameter called the total amplitude of swelling and shrinkage deformation, allowing the exclusion of the soil initial water content when evaluating soil deformation. After comparison of usual indirect methods to classify swelling soils, a predictive method of clay-rich soils deformation under moisture variation for Karal was proposed and discussed. [ABSTRACT FROM AUTHOR]

Worldwide, interest in mitochondria is constantly growing, as evidenced by scientific statistics, and studies of the functioning of these organelles are becoming more prevalent than studies of other cellular structures. In this analytical review, mitochondria are conditionally placed in a certain cellular center, which is responsible for both energy production and other non-energetic functions, without which the existence of not only the eukaryotic cell itself, but also the entire organism is impossible. Taking into account the high multifunctionality of mitochondria, such a fundamentally new scheme of cell functioning organization, including mitochondrial management of processes that determine cell survival and death, may be justified. Considering that this issue is dedicated to the memory of V. P. Skulachev, who can be called mitocentric, due to the history of his scientific activity almost entirely aimed at studying mitochondria, this work examines those aspects of mitochondrial functioning that were directly or indirectly the focus of attention of this outstanding scientist. We list all possible known mitochondrial functions, including membrane potential generation, synthesis of Fe-S clusters, steroid hormones, heme, fatty acids, and CO2. Special attention is paid to the participation of mitochondria in the formation and transport of water, as a powerful biochemical cellular and mitochondrial regulator. The history of research on reactive oxygen species that generate mitochondria is subject to significant analysis. In the section "Mitochondria in the center of death", special emphasis is placed on the analysis of what role and how mitochondria can play and determine the program of death of an organism (phenoptosis) and the contribution made to these studies by V. P. Skulachev. [ABSTRACT FROM AUTHOR]

The physical blending method was used in order to prepare nitrile-butadiene rubber/polyamide elastomer/single-walled carbon nanotube (NBR/PAE/SWCNT) composites with better thermal-oxidative aging resistance. The interactions between SWCNTs and NBR/PAE were characterized using the Moving Die Rheometer 2000 (MDR 2000), rheological behavior tests, the equilibrium swelling method, and mechanical property tests. The 100% constant tensile stress and hardness of NBR/PAE/SWCNT composites increased from 2.59 MPa to 4.14 MPa and from 62 Shore A to 69 Shore A, respectively, and the elongation decreased from 421% to 355% with increasing SWCNT content. NBR/PAE/SWCNT composites had improved thermal-oxidative aging resistance due to better interactions between SWCNTs and NBR/PAE. During the aging process, the tensile strength and elongation at break decreased with the increase in aging time compared to the unaged samples, and the constant tensile stress gradually increased. There was a more significant difference in the degradation of mechanical properties when aged in a variety of oils. The 100% constant tensile stress of NBR/PAE/SWCNT composites aged in IRM 903 gradually increased with aging time while it gradually decreased in biodiesel. The swelling index gradually increased with increasing SWCNT content. Interestingly, the swelling index of the composites in cyclohexanone decreased with the increase in SWCNT content. The reasons leading to different swelling behaviors when immersed in different kinds of liquids were investigated using the Hansen solubility parameter (HSP) method, which provides an excellent guide for the application of some oil-resistant products. [ABSTRACT FROM AUTHOR]

Background: Minimally invasive approaches to the hip joint for total hip arthroplasty such as the DAA ("Direct Anterior Approach with bikini incision") are increasingly utilized. According to the literature, this approach is more muscle-sparing, results in less postoperative pain, and achieves higher patient satisfaction. The existence of postoperative lymphedema after hip arthroplasty is hardly considered. The aim of this paper is to contribute to the evaluation of the different access methods related to postoperative lymphedema and their functional outcomes. Methods: This is a prospective non-randomized study at an orthopedic specialist clinic in Northern Europe. The surgeons that performed the arthroplasties are high-volume surgeons in private practice affiliated to the clinic. The study included 188 patients with primary hip arthroplasty in a 1:1 ratio (DAA: standard accesses (posterior, transgluteal, and anterolateral access)). Epidemiologic data, Harris Hip Score, Oxford Hip Score, European Quality of Life 5, and Visual Analog Scale were collected preoperatively on admission day, 3rd and 5th postoperative day, and follow-up after 1 year. Furthermore, the range of motion, gait, and ability to climb stairs, as well as the presence of hypesthesia were assessed. To evaluate the edema situation, both legs were measured on the 3rd and 5th postoperative day. The prescription of manual lymphatic drainage and remaining swelling conditions 1 year postoperatively were recorded. Results: For each group, 94 patients with a mean age of 61.7 years (DAA 60.7 and standard access 62.6) were included. All but one patient in the DAA group showed postoperative lymphedema (n: 93/94; 98.9%). In the standard surgery group, only n: 37/94 (39.4%) showed swelling symptoms requiring treatment. After 1 year, lymphedema persisted in 20 patients in the DAA group and 0 patients in the standard-OR group. Hypesthesia at the ventral thigh persisted in 16/94 (= 17%) patients of the DAA group versus 0/94 patients of the standard group after 12 months. Of these 16 cases, 10 had concomitant edema (62.5%). The DAA showed better results than the standard accesses in terms of Oxford Hip Score (p < 0.05) and ability to climb stairs (p < 0.05). In contrast, the Visual Analog Scale and patient quality of life results showed no significant difference (p > 0.05). Conclusion: The present study demonstrated the increased incidence of postoperative lymphedema in patients operated on via DAA access using a Bikini-type skin incision. In the follow-up, significantly more hypesthesia of the ventral thigh occurred in the DAA group. Otherwise, the DAA proved to be superior to the standard approaches from a functional point of view at short-term follow-up. Future research is needed to compare the horizontally oblique to the longitudinal oblique skin incision technique in direct anterior hip surgery regarding the above-mentioned adverse effects found in this study. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) have become the most rapidly developing fuel cells in recent years. Proton exchange membranes (PEMs) are one of the most essential components of PEMFCs; however, their performance cannot adapt to the rapid development of today's society. In addition, to replace traditional low-performance membranes and meet technical development and commercial needs, most studies are focusing on the design and preparation of ideal PEMs with low electron permeability, low fuel and oxidizer permeability, high proton conductivity, excellent mechanical and chemical properties, and low cost. Herein, we review PEMs based on polymers in the aromatic hydrocarbon family. Owing to their rigid backbone structure, most aryl polymers are lowly soluble in most solvents. The solubility of a polymer can be improved by introducing different monomers that modify the aromatic hydrocarbon compounds in the main or side chain. The PEM can then be prepared using the solution casting method. To improve the proton conductivity, water uptake, mechanical properties, and oxidation stability of PEMs, many researchers have reported the use of various approaches: sulfonation, immersion in hydrochloric acid or phosphoric acid (PA), blending, crosslinking, and addition of inorganic fillers or metal–organic frameworks. The insights provided by this review will assist the development of higher-performance, safer, and cheaper PEMs. • Different kinds of polymers prepared as proton exchange membranes have been reviewed. • The relationship between different properties of proton exchange membranes were discussed. • Various modification methods to improve the properties of proton exchange membranes were described. • The further development direction of proton exchange membrane was explored. [ABSTRACT FROM AUTHOR]

Compacted bentonite is often considered the optimum buffering material in deep geological repository for high-level radioactive waste (HLRW). The investigation of Mt (montmorillonite) swelling behaviors under non-isothermal saline conditions is essential for understanding the buffering property deterioration of compacted bentonite. To reveal the coupling relationship of swelling deformation and interlayer molecular behaviors of Mt, molecular models of Mt-salt system were constructed. The cation exchange and swelling process were studied by molecular dynamics (MD) simulation. We find that counterion replacement is closely related to the interlayer interactions and hydrated complex structure. The entry of K+ and Ca2+ into the Na-Mt interlayer brings about a significant increase in its stability and water retaining capacity, enhancing local agglomeration of interlayer water molecules. This results in inhibition of the swelling deformation of Mt. Besides, elevated temperature reduces the order of interlayer water molecules and increases the interlayer ionic correlation, leading to an increase in basal space. However, these variations of interlayer properties are antagonistic for Mt swelling, resulting in a weaker thermal effect compared to the salination effect. And the swelling behaviors of Mt is essential to evaluate the final swelling deformation of bentonite. These findings provide a clear insight into the mineral changes in bentonite swelling from a molecular view. [ABSTRACT FROM AUTHOR]

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare primary cutaneous lymphoma which often be very complexed to be diagnosed. Here we reported a case of a 38-year-old lady with wax and wane course of left facial swelling associated with prolonged pyrexia of unknown origin, lethargy and prominent weight loss. Multiple investigations were conducted to reach to the conclusive diagnosis. Histopathological showed infiltration of neoplastic lymphoid cells within the adipocyte clusters with hyperchromatic nuclei, small nucleoli and scant cytoplasm. Immunohistochemical analysis were immunoreactive to CD3, CD8 & TIA and negative to CD20, CD4 & CD56. Based on clinical findings, histopathology report and immunohistochemical analysis, the patient diagnosed with SPTCL. Hence, any suspicious maxillofacial swelling without obvious sign of infection and trauma shall be investigated until a final diagnosis is reached. [ABSTRACT FROM AUTHOR]

Sulfonic resins can replace homogeneous sulfonic acids in the oxidation of alcohols with the H2O2/KBr system. The performance of different resins was tested with methyl 9(10)-hydroxystearate, a secondary fatty alcohol. The structural features of the resin were more important than the acid strength for the catalytic performance of this reaction. The optimization of the reaction conditions allows the recovery of the resin, although regeneration is required due to the active role of KBr, and a significant loss of sulfonic groups can be detected after nine runs. In the case of primary fatty alcohols, the oxidation leads to carboxylic acids, which are esterified with the starting alcohol under the acidic conditions. For cyclic secondary alcohols, the steric hindrance around the hydroxyl group seems to be important for the efficiency of the oxidation to ketone. [ABSTRACT FROM AUTHOR]

Impurities such as carbon atoms play a significant role in the void swelling of irradiated metals. The phenomenon is important to both materials designs in which impurities are intentionally introduced and accelerator-based ion irradiation testing in which impurities are introduced unintentionally as contaminants. Here, we report rate theory simulations of void nucleation in pure Fe, which are irradiated by 5-MeV Fe ions, as one typical irradiation condition used in nuclear material testing. Based on kinetics obtained previously from ab initio calculations, Multiphysics Object-Oriented Simulation Environment (MOOSE)–based numerical solvers were used to simulate defect distributions and void nucleation. Vacancy-carbon interactions increase the effective migration energies of carbon and decrease the diffusivity prefactors. The vacancy mobility reduction decreases both interstitial flux and vacancy flux. However, the vacancy flux reduction is more significant than that of interstitials, leading to reduced void nucleation in bulk. On the other hand, reduced vacancy flux toward the surface leads to local vacancy pileups, leading to locally enhanced void nucleation. These two combined effects make the void nucleation profile deviate from the displacements per atom (dpa) peak, and void swelling peaks shift to the near-surface region. The transition from deep swelling to near-surface swelling is plotted as a function of dpa rate, carbon concentration, and temperature. The study shows that the swelling peak shifting caused by the carbon effect can be avoided by either reducing dpa rates or increasing irradiation temperatures. The study is important to understand swelling behaviors and to optimize irradiation parameters for accelerator-based swelling testing. [ABSTRACT FROM AUTHOR]

The dimensional stability and equilibrium moisture content (EMC) of thermally modified hardwoods were studied. Lumber of yellow-poplar (Liriodendron tulipifera); red oak (Quercus borealis); white ash (Fraxinus americana), red maple (Acer rubrum); hickory (Carya glabra), and black cherry (Prunus serotina) were modified in industrial thermo-vacuum system. The water absorption rate, EMC, swelling, anti-swelling efficiency, shrinkage, anti-shrinkage efficiency, and anisotropy of the specimens were measured and compared to unmodified wood. The results show that thermal modification significantly decreased water absorption of wood which leads to improved dimensional stability. Specifically, thermally modified wood showed reduced EMC (22% in hickory to 59% in red maple), increased water absorption repellent (14.9% in black cherry to 29.6% in yellow-poplar), increased anti-swelling efficiency (14.2% in hickory to 71.4% in ash), increased anti-shrinkage efficiency (23.5% in red maple to 65.6% in ash), and reduced anisotropy coefficient (4.7% in red oak to 31.9% in black cherry). [ABSTRACT FROM AUTHOR]

The objective of this study was to determine if performing electrical stimulations (E-STIM) under blood flow restriction (BFR) would result in a greater protective effect against symptoms of muscle damage. 18 individuals (9 females) completed a damaging bout of exercise followed by a low frequency E-STIM treatment protocol on both arms, one of which was completed under BFR. The treatment protocol was then repeated 24-hours post-exercise. There were main effects of time for muscle thickness (pre: 3.5 cm; 48 h post: 3.8 cm; BF10 = 88.476), discomfort (pre: 0.0 au; 48 h post: 4.2 au; BF10 = 241.996), and isometric strength (pre: 278 N; 48 h post: 232 N; BF10 = 10,289.894) which all changed as a result of the damaging exercise protocol, but there were no differences between conditions [all Bayes Factors (BF10) < 0.28]. The effectiveness of low frequency E-STIM for preventing the onset of exercise-induced muscle damage would not appear to be enhanced if performed under BFR. [ABSTRACT FROM AUTHOR]

One of the geotechnical-engineering roles is soil stabilization, because it affects the long-term strength and functionality of structures. For suitability and durability of expansive soils for construction projects, shear strength, bearing capacity and other characteristics can be enhanced through the stabilization process. This study is focused on the effects of steel factory dust (SFD) as an additive on the improvement of the undesired geotechnical properties of expansive soil (CH soil). A series of laboratory tests were conducted on intact and treated samples. SFD was added by 0, 2, 4, 6, 8 and 10% to the dry soil. The conducted tests are consistency, specific-gravity, modified Proctor compaction, swelling-pressure and -percent and unconfined compression tests. The addition of SFD reduced the values of liquid and plastic limits, plasticity index, modulus of elasticity and allowable bearing capacity. Significantly, the 10% SFD addition significantly reduced swelling percent and pressure by 26.8% and 25.4%, respectively while notably increasing the unconfined compressive strength (UCS) from 475 MPa to 629 MPa. SFD was found to be a successful waste material in improving expansive soil by using 10% as the best addition percent, which usefully saves the environment. [ABSTRACT FROM AUTHOR]

Green algae are a sustainable source of biopolymers for the global demand due to their high photosynthetic efficiency. This article describes the extraction of cellulose from plant systems represented by Ulva lactuca species. In order to extract various substances, algae were finely ground with the help of solvents (liquid media). This was carried out to achieve the necessary conditions that help reduce the resistance this phase shows in regard to the transport and transfer of the species being extracted. The highest yield of extracted cellulose (20,944%) was obtained for the following factors: S/L = 1/20; conc. ethanol = 90%, conc. salts = 4 g/L. Hydrogel membranes are a unique class of macromolecular networks that contain a large fraction of aqueous solvent within their structure. With the cellulose extracted from algae, we obtained membranes which underwent the process of swelling in liquid media (ethyl alcohol) of different concentrations. The swelling of biocellulose membranes in alcoholic solutions of high concentrations was investigated. It was observed that the process of absorption of the alcoholic solution by the membrane occurred rapidly in the first part. After stabilization, the membranes continued to absorb at a slower rate until stabilization or saturation concentration was reached. [ABSTRACT FROM AUTHOR]

PEO-based non-isocyanate polyhydroxyurethane (NIPU, PHU) networks physically modified with octa(3-hydroxy-3-methylbutyldimethylsiloxy)POSS (8OHPOSS) were synthesized via one-pot one-step approach. POSS was introduced into the polymer matrix in the amount of 1–10 wt%. Polar hydroxyls on the vertex groups of POSS allowed for uniform dispersion even up to high loadings (10 wt%). Composites exhibit enhanced thermal stability in comparison to the pristine matrix. FTIR analysis confirmed that POSS strengthens the hydrogen bonding in the material. Upon POSS introduction, plasticization was observed with a peculiar trend change at POSS loadings over 5 wt%. Glass transition temperature of highly crystalline 8OHPOSS was measured and reported to be at around 3 °C. NIPUs at hand exhibit high water absorption (around 200 wt%) typical for hydrogels. Swelling studies show that 8OHPOSS enhances PHUs hydrogels absorption capacity in phosphate-buffered saline (PBS). Higher absorption capacity in PBS solution in comparison to distilled water is an uncommon phenomenon in hydrogels. [ABSTRACT FROM AUTHOR]

The stabilisation of expansive clay subgrades using recycled glass (RG) was proposed, as a sustainable ground improvement technique. Previous studies mainly focused on using RG powder with contents up to 10%, while the current study utilised sand-size particles and up to 40% RG content. Physical properties, compressibility, strength characteristics, and long-term climatic effects on the volumetric behaviour of stabilised clay were investigated. Volumetric responses of stabilised clay were analysed through a constitutive model developed for environmentally stabilised clay. The experimental results revealed that the plasticity of mixtures decreased by 30% as RG content increased to 40%. By using larger RG particles, the strength and bearing capacity increased by about 45% and 130% with the addition of 25% RG. However, adding about 6% of glass powder was sufficient to increase the strength and bearing capacity to about 100% and 200%, respectively. The swell-shrink results suggested that the maximum swelling was achieved in the second cycle in which the clay classification was converted from medium to high expansive clay. The experimental results were also compared and discussed with corresponding data collected from the literature. The outcomes of this study advance the prediction and understanding of the mechanical behaviour of RG-stabilised clay. [ABSTRACT FROM AUTHOR]

Nanopapers fabricated from cellulose nanofibers (CNFs) drastically swell to form hydrogels when they are in contact with water. This gelation makes contrast with conventional papers that simply deform without drastic volume increase. While the volume increase is qualitatively obvious from the macroscopic visual inspection, its quantitative understanding is nontrivial because of the difficulty in the detection of the boundary between the nanopaper hydrogel and the residual or extra water. In this study, we use single particle tracking (SPT) to reveal the swelling-based gelation phenomenon of cellulose nanopapers. The diffusive dynamics of probe particles uncovers the transient process of swelling, and equilibrium analysis reveals the dependence of volume increase fundamentally dependent on the amount of water to be in contact with the nanopapers. Comparison with the aqueous CNF dispersion without drying reveals the difference in the texture of the nanopaper hydrogels from them. [ABSTRACT FROM AUTHOR]

The northern coastal strip of Venezuela with a semiarid climate presents conditions for the development of extensive areas with the presence of expansive clays, and, this is the main pathology of its communication routes due to deformation in the surrounding civil works. This contribution characterizes the presence of expansive clays in northern Venezuela in 81 samples distributed in several states of the country. The study included the determination of geomechanical properties through field work and laboratory tests by Atterberg limits, consistency indices and expansion tests as well as the relationship between the indexes and information from edometer tests. The soil grain size is mainly fine (silts and clays), in the Anzoátegui state the average content of fine grains is 86%, while in Falcón and Miranda they are a little lower, 82% and 67%, respectively. In general, the plasticity index (PI) of these expansive clays is high, with an overall average of 23, although the region of Falcón state presented a moderate average (18). The correlations between the expansion pressure and the PI showed a high correlation. These results corroborate that the criterion used to evaluate the Expansion Potential of a clay soil based on the PI proposed by Chen (1988), is a fairly adequate criterion to be used in the study and identification of the expansive behavior of these types of soils. [ABSTRACT FROM AUTHOR]

The aim of the current study was to fabricate a pH-sensitive hydrogels for controlled release of Bovine serum albumin (BSA) protein. In this research work, polyvinylalcohol grafted poly(acrylic acid-co-2-acrylamido-2-methylpropane sulfonic acid) (PVOH-g-poly(AA-co-AMPS)) hydrogels with varying AA/AMPS molar ratio were synthesized through free radical graft copolymerization of partially neutralized acrylic monomers and characterized by Fourier transform infrared spectroscopy, Elemental analysis, X-ray diffraction, and Scanning electron microscopy, thermogravimetric analysis. Then, mechanical proprieties of hydrogels were investigated, and drug release behavior with Bovine serum albumin (BSA) as model drug was studied in vitro. The effect of AA/AMPS molar ratio, pH media on the swelling property of hydrogels was optimized. Results indicated that the strong interaction in the hydrogels resulted in the formation of a more stable copolymer. The high values of the grafting percentage which exceeds 800% confirmed the high performance of the grafting and the successful synthesis. Grafting AMPS onto PVOH/AA improved both thermal stability and mechanical properties of hydrogel. The hydrogel is simultaneous sensitive to pH and ionic strength; the swelling ratio maximizes at pH 6.8 medium and shrinks at pH 1.2, and decreases as the ionic strength increases; the swelling dynamic mechanism was explained well by Fickian diffusion and Schott's pseudo-second-order models. Different kinetic models were applied, and it has been observed that release profile of BSA best followed the Hixson–Crowell for the release of drug in all release media. However, Zero order and Korsmeyer–peppas models only for pH 1.2 and pH 7.4. The swelling of the hydrogels and release of BSA from the drug loaded hydrogels occurred through non-Fickian diffusion mechanism. It is believed that this hydrogel could be potentially used for localized drug delivery. [ABSTRACT FROM AUTHOR]

Swelling in the vocal folds is caused by the local accumulation of fluid, and has been implicated as a phase in the development of phonotraumatic vocal hyperfunction and related structural pathologies, such as vocal fold nodules. It has been posited that small degrees of swelling may be protective, but large amounts may lead to a vicious cycle wherein the engorged folds lead to conditions that promote further swelling, leading to pathologies. As a first effort to explore the mechanics of vocal fold swelling and its potential role in the etiology of voice disorders, this study employs a finite-element model with swelling confined to the superficial lamina propria, which changes the volume, mass, and stiffness of the cover layer. The impacts of swelling on a number of vocal fold kinematic and damage measures, including von Mises stress, internal viscous dissipation, and collision pressure, are presented. Swelling has small but consistent effects on voice outputs, including a reduction in fundamental frequency with increasing swelling (10 Hz at 30 % swelling). Average von Mises stress decreases slightly for small degrees of swelling but increases at large magnitudes, consistent with expectations for a vicious cycle. Both viscous dissipation and collision pressure consistently increase with the magnitude of swelling. This first effort at modeling the impact of swelling on vocal fold kinematics, kinetics, and damage measures highlights the complexity with which phonotrauma can influence performance metrics. Further identification and exploration of salient candidate measures of damage and refined studies coupling swelling with local phonotrauma are expected to shed further light on the etiological pathways of phonotraumatic vocal hyperfunction. [ABSTRACT FROM AUTHOR]