Swelling Measurements Research Articles

Measurements of Nitrile Rubber Absorption of Hydrocarbons: Trends for Sustainable Aviation Fuel Compatibility

The commercial aviation sector is seeking to reach net zero CO2 emissions by 2050, with sustainable aviation fuel (SAF) being the most important lever. However, SAF is currently limited by ASTM specifications to a maximum of 50%v blending with conventional jet fuel. One reason for the current blend limit is motivation to maintain o-ring swelling consistent with 100% petroleum fuel. This work explores the relationships between o-ring swelling of SAF blend components, model compounds, and various blends in nitrile rubber compared to conventional fuel swelling. Specifically, optical dilatometry measurements were used to gather swell propensity data for 39 different hydrocarbon dopants at 8%v in an iso-alkane solution, 4 dopants at 7 different concentrations, and 19 different fuels or fuel blends. This study also highlights the advantages of using swell measurements, such as those employed here, as a quality control metric instead of the current 8%v aromatics requirement. Notably, the potential is shown to maintain swelling in the conventional fuel range with fuels composed of less than 8%v aromatics.

The Adsorption Efficiency of Regenerable Chitosan-TiO2 Composite Films in Removing 2,4-Dinitrophenol from Water.

In this work, the great performance of chitosan-based films blended with TiO2 (CH/TiO2) is presented to adsorb the hazardous pollutant 2,4-dinitrophenol (DNP) from water. The DNP was successfully removed, with a high adsorption %: CH/TiO2 exhibited a maximum adsorption capacity of 900 mg/g. For pursuing the proposed aim, UV-Vis spectroscopy was considered a powerful tool for monitoring the presence of DNP in purposely contaminated water. Swelling measurements were employed to infer more information about the interactions between chitosan and DNP, demonstrating the presence of electrostatic forces, deeply investigated by performing adsorption measurements by changing DNP solutions' ionic strength and pH values. The thermodynamics, adsorption isotherms, and kinetics were also studied, suggesting the DNP adsorption's heterogeneous character onto chitosan films. The applicability of pseudo-first- and pseudo-second-order kinetic equations confirmed the finding, further detailed by the Weber-Morris model. Finally, the adsorbent regeneration was exploited, and the possibility of inducing DNP desorption was investigated. For this purpose, suitable experiments were conducted using a saline solution that induced the DNP release, favoring the adsorbent reuse. In particular, 10 adsorption/desorption cycles were performed, evidencing the great ability of this material that does not lose its efficiency. As an alternative approach, the pollutant photodegradation by using Advanced Oxidation Processes, allowed by the presence of TiO2, was preliminary investigated, opening a novel horizon in the use of chitosan-based materials for environmental applications.

Evaluation of the efficacy of topical rifamycin application on postoperative complications after lower impacted wisdom teeth surgery

PurposeThis study aimed to evaluate the efficacy of a single-dose topical rifamycin application on postoperative complications after impacted lower third molar surgery. Materials and methodsThis prospective, controlled clinical study consisted of individuals with bilaterally impacted lower third molars that would be extracted for orthodontic reasons. The extraction sockets were irrigated with 3 ml/250 mg of rifamycin solution in Group 1, while in Group 2 (control group) the extraction sockets were irrigated with 20 ml of physiological saline. Pain intensity was measured daily for 7 days by using visual analog scale. Trismus and edema were evaluated preoperatively and on the postoperative days 2 and 7 by calculating the proportional changes in maximum mouth opening and mean distance between reference points of the face, respectively. Paired samples t-test, Wilcoxon signed rank test and Chi-square test were used to analyze the study variables. Results35 patients (19 female, 16 male) were included in the study. The mean age of all participants was 22.19±4.98. Alveolitis was observed in 8 patients, (6 in the control group, 2 in the rifamycin group). There was no statistically significant difference between groups in terms of trismus and swelling measurements on the 2nd and 7th postoperative days (p>0.05). VAS scores were significantly low in rifamycin group on postoperative days 1 and 4 (p<0.05). ConclusionWithin the limits of the present study, topical rifamycin application reduced the incidence of alveolitis, prevented infection, and provided analgesic effect after surgical removal of impacted third molars.

Fabrication and characterization of bioprints with Lactobacillus crispatus for vaginal application

Bacterial vaginosis (BV) is characterized by low levels of lactobacilli and overgrowth of potential pathogens in the female genital tract. Current antibiotic treatments often fail to treat BV in a sustained manner, and > 50% of women experience recurrence within 6 months post-treatment. Recently, lactobacilli have shown promise for acting as probiotics by offering health benefits in BV. However, as with other active agents, probiotics often require intensive administration schedules incurring difficult user adherence. Three-dimensional (3D)-bioprinting enables fabrication of well-defined architectures with tunable release of active agents, including live mammalian cells, offering the potential for long-acting probiotic delivery. One promising bioink, gelatin alginate has been previously shown to provide structural stability, host compatibility, viable probiotic incorporation, and cellular nutrient diffusion. This study formulates and characterizes 3D-bioprinted Lactobacillus crispatus-containing gelatin alginate scaffolds for gynecologic applications. Different weight to volume (w/v) ratios of gelatin alginate were bioprinted to determine formulations with highest printing resolution, and different crosslinking reagents were evaluated for effect on scaffold integrity via mass loss and swelling measurements. Post-print viability, sustained-release, and vaginal keratinocyte cytotoxicity assays were conducted. A 10:2 (w/v) gelatin alginate formulation was selected based on line continuity and resolution, while degradation and swelling experiments demonstrated greatest structural stability with dual genipin and calcium crosslinking, showing minimal mass loss and swelling over 28 days. 3D-bioprinted L. crispatus-containing scaffolds demonstrated sustained release and proliferation of live bacteria over 28 days, without impacting viability of vaginal epithelial cells. This study provides in vitro evidence for 3D-bioprinted scaffolds as a novel strategy to sustain probiotic delivery with the ultimate goal of restoring vaginal lactobacilli following microbiological disturbances.

Mixtures of colliery spoils and fluidized bed bottom ash: strength and swelling behavior under compressive stress in isolated conditions

The amount and variety of waste materials used in civil engineering are steadily increasing due to the depletion of natural resources and the implementation of environmental policies. A new mixture of colliery spoils and fluidized bed bottom ash was recently developed in Poland, which proved to be prone to excessive, long-term swelling, potentially damaging structures such as road embankments. Numerous papers discuss the heaving mechanisms in spoils or fluidized bed ash. However, no reports analyzing the expansion of their mixture seem to be available. The purpose of this paper is to fill this void. The experiment involved measurements of linear swelling of mixture samples stored inside CBR test molds and isolated from moisture loss/gain. Material expansion is caused by the reactivity of the fluidized bed ash; its content in the mix correlates positively with the final swelling strain. At the same time, colliery spoils provide an environment particularly conducive to the phenomenon’s occurrence. A linear swelling strain of 0.3–3.2% was observed after 6 months (disregarding the first 24 h of rapid volume growth). The expansion of mixtures was also measured under constant compressive stress of 0–100 kPa to better represent their actual working conditions. Based on the results, it is proposed to adapt a mathematical model developed for anhydrite-rich rock to describe the load-swelling relationship in mixtures of colliery spoils with fluidized bed bottom ash. Such a model can be potentially used, e.g., in numerical analyses, to assess the impact of the material’s expansion on embankments.

Interaction enhancement of Lyocell cellulose chains for controlled fibrillation behavior with greener application in eco-textiles

Lyocell is treated as a biodegradable, sustainable, and low-carbon emission cellulose fiber, but it possesses a high fibrillation tendency in the dyeing process which is generally conducted at alkaline, wet and high-temperature conditions. The fibrillation phenomenon seriously reduces the product quality and affects its application in eco-textiles. In response to the problem, a greener and simple fibrillation prevention treatment was innovatively conducted before the coloration process to enhance the interaction of Lyocell cellulose macromolecular chains. A nonionic crosslinker with isocyanate reactive groups was applied for the fibrillation control. The mechanism of the reaction between the nonionic crosslinker and Lyocell cellulose chains was determined through the measurements of fiber swelling, dynamic surface tension, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). It was found that the fibril interaction was significantly enhanced with reduced lateral swelling of Lyocell fibers. The fibrillation tendency was greatly reduced at the treatment condition of 20 g/L, 175 °C, and 80 s. Moreover, the interaction between cellulose chains was further improved after dyed with bifunctional reactive dyes. In comparison to commercial cationic and anionic crosslinkers, the nonionic sample not only showed little effect on the dye fixation, but also added good wrinkle resistance to Lyocell fabrics. The method showed the advantages of a shorter process and low chemical consumption compared to the conventional Lyocell dyeing process. Therefore, this work may promote the development of Lyocell fabric in high-quality and eco-friendly textiles.

Synthesis and characterization of chitosan/cellulose blend reinforced with copper oxide nanoparticles as moisture barrier film

Bio-based plastics emerged as eco-friendly and resource-efficient substitutes for petroleum-based counterparts. Despite the continuous efforts to develop these alternatives, their inferior performance, most notably mechanical and moisture barrier aspects, limits their application. Material hybridization, like polymer blending and nanocomposite technology, are among the methods employed to improve the properties of bioplastics. This present work focuses on synthesizing bioplastic films with 30/70, 50/50, and 70/30 chitosan to cellulose (CH/CE) percent weight ratios. FTIR analysis of the blend films revealed interaction between NH2 and OH, confirming the compatibility between chitosan and cellulose. Analysis of variance showed increasing cellulose content significantly (p < 0.05) enhanced the resistance to swelling. The 30/70-CH/CE film exhibited the least swelling, which is 65.5% lower than the pure chitosan film. Moreover, copper oxide nanoparticles (CuO NPs) were prepared as reinforcement due to its hydrophobicity. Structural and morphological analyses of hydrothermally synthesized CuO nanoparticles confirmed monoclinic and urchin-like structure. Varying amounts of CuO NPs, i.e., 1%, 3%, and 5% w/v were added to the 30/70-CH/CE films to further enhance the moisture barrier properties. The best barrier performance was attained at 5% w/v, indicated by the smallest % swelling (93.25%) and largest contact angle measurement (89.32°). This could be related to the morphological change from fibrous to smoother film surface with increasing amount of CuO NPs. Results suggest the potential of the chitosan/cellulose polymer blend and the copper oxide nanoparticle-reinforced films for moisture barrier applications.

Experimental Dehydration of the Water-Ethanol Mixture by Pervaporation through Membranes Based on Polyvinyl Alcohol: What Conditions for Better Performance?

Abstract: The separation processes are of paramount importance in the industrial field. The techniques used to obtain separation membranes depend on the type of membrane and the applications envisaged.&#x0D; Aim: The objective of the study is to focus on the master membrane allowing better pervaporation of the water-ethanol mixture by varying various parameters such as the polymer content, the polyacrylic acid (PAA) content and the operating variables such as the drying temperature and the stay in the oven. &#x0D; Materials: We fabricated membranes to separate water-ethanol mixtures by the pervaporation process. First, films based on polyvinyl alcohol and acid polyacrylics were prepared using the appropriate solvent (water) with different PAA contents. We then characterized these films using the technique of infrared spectroscopy and the measurement of swelling of these membranes in water / ethanol mixtures. Pervaporation tests were carried out to measure the selectivity and flow of these films with respect to the mixture.&#x0D; Results: All the membranes exhibit a higher permeation flux than that of pure PVA, especially when the PAA content is high. The selectivity to water of these crosslinked membranes, represented by the water content in the permeate is appreciable.&#x0D; Conclusion: The addition of PAA to PVA makes possible the improvement of swelling, the flow is improved as well as the water selectivity and the permeability of the membrane which makes the PVA-PAA alloy a simple and effective method to ensure dehydration of the Water-Ethanol mixture.

Experimental Dehydration of the Water-Ethanol Mixture by Pervaporation through Membranes Based on Polyvinyl Alcohol: What Conditions for Better Performance?

Abstract: The separation processes are of paramount importance in the industrial field. The techniques used to obtain separation membranes depend on the type of membrane and the applications envisaged.&#x0D; Aim: The objective of the study is to focus on the master membrane allowing better pervaporation of the water-ethanol mixture by varying various parameters such as the polymer content, the polyacrylic acid (PAA) content and the operating variables such as the drying temperature and the stay in the oven. &#x0D; Materials: We fabricated membranes to separate water-ethanol mixtures by the pervaporation process. First, films based on polyvinyl alcohol and acid polyacrylics were prepared using the appropriate solvent (water) with different PAA contents. We then characterized these films using the technique of infrared spectroscopy and the measurement of swelling of these membranes in water / ethanol mixtures. Pervaporation tests were carried out to measure the selectivity and flow of these films with respect to the mixture.&#x0D; Results: All the membranes exhibit a higher permeation flux than that of pure PVA, especially when the PAA content is high. The selectivity to water of these crosslinked membranes, represented by the water content in the permeate is appreciable.&#x0D; Conclusion: The addition of PAA to PVA makes possible the improvement of swelling, the flow is improved as well as the water selectivity and the permeability of the membrane which makes the PVA-PAA alloy a simple and effective method to ensure dehydration of the Water-Ethanol mixture.

Improved pervaporation dehydration performance of alginate composite membranes by embedding organo-montmorillonite

In this work, two different montmorillonite (MMT) nanoclays were incorporated in sodium alginate (Alg) solution for fabrication of hybrid membrane for pervaporative separation of aqueous isopropanol solution. Sodium-MMT (Na-MMT) was modified to organo-montmorillonite (O-MMT) using cationic surfactant dialkyldimethyl ammonium chloride (DDAC). The influence of incorporating MMTs on the membrane properties and separation performance was investigated. Intercalating of DDA+ on Na-MMT tailored the chemical structure and morphology of the MMTs. Integrating of MMTs modified the physicochemical properties of the membranes. The membrane morphology shows the homogeneous dispersion of MMTs in athe Alg matrix. Positron annihilation lifetime spectroscopy analysis revealed a tuned microstructure of the membranes. Swelling measurements showed better compatibility of O-MMT than the Na-MMT with the Alg matrix. As a result, AlgO-MMT had better separation performance than the AlgNa-MMT with permeation flux of 4764 g∙m−2∙h−1 and water concentration in permeate of 99.99 wt% on dehydrating 70 wt% IPA/water aqueous solution at 25 °C. Owing to the favorable compatibility between the polymer and filler, AlgO-MMT membrane demonstrated stability at different pervaporation operating conditions and long-term use. Our results demonstrated that the properties and separation performance of Alg membrane can be enhanced through incorporation of O-MMTs.

Preparation and Characterization of Poly(vinyl acetate-co-2-hydroxyethyl methacrylate) and In Vitro Application as Contact Lens for Acyclovir Delivery.

A series of poly(vinyl acetate-co-2-hydroxyethylmethacrylate)/acyclovir drug carrier systems (HEMAVAC) containing different acyclovir contents was prepared through bulk free radical polymerization of 2-hydroxyethyl methacrylate with vinyl acetate (VAc) in presence of acyclovir (ACVR) as the drug using a LED lamp in presence of camphorquinone as the photoinitiator. The structure of the drug carrier system was confirmed by FTIR and 1HNMR analysis, and the uniform dispersion of the drug particles in the carrier was proved by DSC and XRD analysis. The study of the physico-chemical properties of the prepared materials, such as the transparency, swelling capacity, wettability and optical refraction, was carried out by UV-visible analysis, a swelling test and measurement of the contact angle and the refractive index, respectively. The elastic modulus and the yield strength of the wet prepared materials were examined by dynamic mechanical analysis. The cytotoxicity of the prepared materials and cell adhesion on these systems were studied by LDH assay and the MTT test, respectively. The results obtained were comparable to those of standard lenses with a transparency of 76.90-89.51%, a swelling capacity of 42.23-81.80% by weight, a wettability of 75.95-89.04°, a refractive index of 1.4301-1.4526 and a modulus of elasticity of 0.67-1.50 MPa, depending on the ACVR content. It was also shown that these materials exhibit no significant cytotoxicity; on the other hand, they show significant cell adhesion. The in vitro dynamic release of ACVR in water revealed that the HEMAVAC drug carrier can consistently deliver uniformly adequate amounts of ACVR (5.04-36 wt%) over a long period (7 days) in two steps. It was also found that the solubility of ACVR obtained from the release process was improved by 1.4 times that obtained by direct solubility of the drug in powder form at the same temperature.

FPGA-based online voltage/current swell segmentation and measurement

Power-signal distortion is one of the main problems industry faces since it is produced by the use of non-linear loads and environmental disturbances. Swells are among the most common electrical disturbances that cause low power quality (PQ) in electric-energy delivery systems. Different methodologies have been proposed to detect disturbances, and as one of the most common electrical disruptions, the monitoring of voltage/current swells is an essential task for opportune correction and increase of the electric-system PQ. Unfortunately, most of the proposed methods for PQ monitoring do not perform a measurement of the disturbance time span. Hence, in this work, a novel method for detecting and measuring the time-length of voltage/current swells through spline interpolation and Otsu segmentation, implemented in an FPGA, is proposed. Obtained results from signals generated through a computer model and acquired from real experimentation demonstrate that the proposed approach can measure swell disturbances in the electric voltage/current signal from a distribution system with high resolution and precision, performing the time-span measurement of a swell disturbance in 81.3 μs, with high certainty of up to 99.945%. Furthermore, the portability of the proposed hardware processing unit is shown by its implementation in FPGA devices from two different vendors.

Attenuation of COX-2 enzyme by modulating H2O2-mediated NF-κB signaling pathway by monoamine oxidase inhibitor (MAOI): a further study on the reprofiling of MAOI in acute inflammation.

This study aims to investigate the anti-inflammatory mechanism of monoamine oxidase inhibitor (MAOI) in carrageenan (CARR) induced inflammation models to reprofile their use. We also aimed to explore the role of monoamine oxidase (MAO)-mediated H2O2-NF-κB-COX-2 pathway in acute inflammation. In vitro anti-inflammatory activity and hydrogen peroxide (H2O2) scavenging activity were performed according to the established procedure. Inflammation was induced using CARR in BALB/c mice at the foot paw and peritoneal cavity. Hourly measurement of paw swelling was performed. The level of nitric oxide (NO), myeloperoxidase (MPO), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2) and nuclear factor κB (NF-κB) was determined using enzyme-linked immunosorbent assay (ELISA). Peritoneal fluid was collected to investigate total count, differential count of leukocytes, and capillary permeability. In vitro anti-inflammatory evaluations revealed the potential role of MAOI to inhibit heat-induced protein denaturation and human red cell membrane destabilization. H2O2 inhibition activity of MAOI also proved their powerful role as an H2O2 scavenger. Treatment with MAOI in CARR-induced mice significantly reduced paw edema, leukocyte extravasation, and total and differential leukocyte count. The result of ELISA showed MAOI effectively reduce the level of COX-2, PGE2 and NF-κB in inflamed tissue. In short, this study demonstrates that inhibition of H2O2 by MAOI alleviates CARR-induced paw edema possibly by inhibiting the H2O2-mediated NF-κB-COX-2 pathway. The present investigation identifies MAOI might reprofile for the treatment of acute inflammation also, the MAO enzyme may use as a novel therapeutic target to design and develop new class of anti-inflammatory agents.

The quantification of anisotropy in graphene/natural rubber nanocomposites: Evaluation of the aspect ratio, concentration, and crosslinking

AbstractIn the processing of nanocomposites, high shear stresses at elevated temperatures orient two‐dimensional nanoparticles like graphene. This orientation leads to anisotropic mechanical, thermal or barrier properties of the nanocomposite. This anisotropy is addressed in this study by comparing graphene (few‐layer graphene, FLG) with a nanoscaled carbon black (nCB) at a filler content of 3 phr, by varying the vulcanization, and by comparing different FLG contents. Transmission electron microscopy gives insight into the qualitative orientation in the nanocomposite with FLG or nCB. The storage moduli parallel and normal to the orientation reveal the direction dependency of reinforcement through dynamic mechanical analysis (DMA). Dimensional swelling measurements show a restriction of the expansion parallel to the FLG orientation, and an increased expansion normal to the orientation. The vulcanization system and crosslinking determine the respective level of property values, and higher crosslinking densities increase the anisotropy in DMA resulting in values of up to 2.9 for the quantified anisotropy factor. With increasing FLG content, the anisotropy increases. A comparison of the results reveals swelling measurements as the most suitable method for the determination of anisotropy. Compared to recent literature, the presented processing induces higher anisotropy, leading to higher reinforcing effects in the direction of orientation.

Prediction of Swelling of Polypropylene Separators and Its Effect on the Lithium-Ion Battery Performance

The safety and reliability of lithium-ion batteries depend on porous separators, many of which are made of polymer materials, such as polypropylene. Favorable interactions between a separator and organic electrolyte solvents used in the batteries often induce separator swelling. Swelling increases the electric resistance of the cell and is accompanied by plasticization of the separator, which also affects the battery’s performance. Here we propose a model based on Flory’s theory of polymer solutions which can predict the swelling of a porous polymer separator based on the Flory–Huggins parameter for polymer–solvent interactions. Despite the complexity of the polymer structure, introducing only two additional parameters provides predictive capability for the model. These two parameters can be obtained based on experimental measurements of separator swelling in two different solvents; the model also requires the Flory–Huggins parameter as an input, which can be calculated based on the UNIFAC-FV group contribution method for a given polymer–solvent pair. We illustrated the applicability of this model to recent experimental data on the swelling of polypropylene separators in various solvents. We also showed a simple relation between the separator swelling and an increase in cell resistance. Our model can be used for a quick assessment of various polymer–solvent pairs for application in lithium-ion batteries.

PREOPERATIVE ANKLE SWELLING DOES NOT AFFECT POSTOPERATIVE WOUND COMPLICATIONS FOLLOWING ANKLE FRACTURE SURGERY

Swelling following an ankle fracture is commonly believed to preclude surgical fixation, delaying operative treatment to allow the swelling to subside. This is in an attempt to achieve better soft tissue outcomes. We aim to identify whether pre-operative ankle swelling influences postoperative wound complications following ankle fracture surgery.This is a prospective cohort study of 80 patients presenting to a tertiary referral centre with operatively managed malleolar ankle fractures.Ankle swelling was measured visually and then quantitatively using the validated ‘Figure-of-eight’ technique. Follow-up was standardised at 2, 6, and 12 weeks post-operatively. Wound complications, patient co-morbidities, operative time, surgeon experience, and hospital stay duration were recorded.The complication rate was 8.75% (n=7), with 1 deep infection requiring operative intervention and all others resolving with oral antibiotics and wound cares. There was no significant difference in wound complication rates associated with quantitative ankle swelling (p=0.755), visual assessment of ankle swelling (p=0.647), or time to operative intervention (p=0.270).Increasing age (p=0.006) and female gender (p=0.049) had a significantly greater probability of wound complications. However, BMI, smoking status, level of the operating surgeon, and tourniquet time were not significantly different.Visual assessment of ankle swelling had a poor to moderate correlation to ‘Figure-of-eight’ ankle swelling measurements ICC=0.507 (0.325- 0.653).Neither ankle swelling nor time to surgery correlates with an increased risk of postoperative wound complication in surgically treated malleolar ankle fractures. Increasing patient age and female gender had a significantly greater probability of wound infection, irrespective of swelling. Visual assessment of ankle swelling is unreliable for quantifying true ankle swelling.Operative intervention at any time after an ankle fracture, irrespective of swelling, is safe and showed no better or worse soft tissue outcomes than those delayed for swelling.

Accelerated fission rate irradiation design, pre-irradiation characterization, and adaptation of conventional PIE methods for U-10Mo and U-17Mo

Metallic U alloys have high U density and thermal conductivity and thus have been explored since the beginning of nuclear power research. Alloys of U with modest amounts of Mo, such as U-10 wt % Mo (U-10Mo), are of particular interest because the γ-U crystal structure in this alloying addition shows prolonged stability in reactor service. Historically, radiation data on U-10Mo fuels were collected in Na fast reactors or lower temperature research reactor conditions, but little is known about irradiation behavior, particularly swelling and creep, at irradiation temperatures between 250 and 500°C. This work discusses the methodology and pre-irradiation characterization results from a U-Mo irradiation campaign performed in the High Flux Isotope Reactor at Oak Ridge National Laboratory. U-10Mo and U-17Mo samples irradiations are being completed at temperatures ranging from 250 to 500°C to three targeted fission densities between 2 × 1020 and 1.5 × 1021 fissions per cubic centimeter. Swelling measurement of the specimen sizes studied here required development and assessment of new methods for volume determination before and after irradiation. Laser profilometry and X-ray computation tomography (XCT) were used to provide preirradiation characterization of samples to determine the error and applicability of each to determine swelling following irradiation. These outcomes are contextualized through use of BISON simulations performed to assess the predicted expansion of U-Mo fuels subjected to the irradiation conditions of this work. Use of existing BISON fuel performance models predicted a maximum of 7% swelling under the irradiation conditions of this study. Pre-irradiation characterization revealed the as-cast U-Mo fuel samples were uniformly large-grained fully cubic U crystals with small U-C/N bearing precipitates and pores distributed throughout. Samples were found to contain a bulk porosity between .4 and 3% because of the casting process. Local porosity in areas far from large, interconnected pores was found by Slice-and-View to be under .2%. Nanometer-sized precipitates rich in C and N were identified in all samples, likely because of impurities during the fabrication process. Dendritic bands were also observed throughout the samples. These bands were characterized by variable Mo content that deviated from the overall Mo content by 2–3 wt %. No other microstructural features were correlated to these bands. Mechanical properties were found to be slightly strengthened compared to literature reports of bulk U-Mo fuels due to the nano-scale precipitates throughout the sample.

Probing the tightly bound layer in poly(vinyl alcohol) thin films using swelling measurements.

A strongly adsorbed, tightly bound polymer layer can exist at the polymer/substrate interface in polymer thin films and polymer nanocomposites. The characteristics of the tightly bound layer have long been of interest because of its effect on physical properties. However, direct investigations are challenging as the layer is buried deep within the sample. A common approach to access the tightly bound layer is by rinsing or washing away the loosely bound polymer using a good solvent. While this enables direct investigations of the tightly bound layer, it is unclear if the layer remains unperturbed by the preparation process. Therefore, in situ techniques that can probe the tightly bound layer without strongly perturbing it are preferable. In previous work (P. D. Lairenjam, S. K. Sukumaran and D. K. Satapathy, Macromolecules, 2021, 54, 10931-10942), we introduced an approach to estimate the thickness of the tightly bound layer at the chitosan/silicon interface using swelling of nanoscale thin films when exposed to solvent vapour. To determine the general validity of the approach, in this work we investigated the swelling of poly(vinyl alcohol) (PVA) thin films using two independent techniques: spectroscopic ellipsometry and X-ray reflectivity. We found that the swelling kinetics for thin films of initial thickness in the range 18-215 nm could be described by a single time-dependent swelling ratio, c(t), provided we account for a tightly bound layer of thickness 15 nm at the polymer/substrate interface. Consistent with the conclusions from the swelling measurements, electron density profiles determined by modeling X-ray reflectivity data clearly indicated the existence at the polymer/substrate interface of a 15 nm thick layer of a slightly higher density than the rest of the film. The early-time diffusion coefficient of H2O in PVA determined from the temporal evolution of the mass uptake of the solvent vapour was found to decrease by 3-4 orders of magnitude when the film thickness decreased by approximately an order of magnitude.

How Do Lay People Identify Knee Swelling and What Would They Do About It: Survey Results in the Context of an Event on the Topic of Knee Osteoarthritis

Objective: Besides pain, joint stiffness and muscle weakness, swelling is a common symptom of knee osteoarthritis. According to the literature, there are clinical tests such as the bulge sign or circumference measurement as part of the clinical examination to identify knee swelling. Pharmacological interventions, knee bandages, temporary sports bans and physical interventions are effective decongestant measures. In the conservative treatment of knee osteoarthritis, the promotion of self-management principles is crucial. However, the general population´s level of knowledge regarding the identification and treatment of knee swelling is unknown. To get directly in contact with lay people, a crowdsourcing approach is appropriate. Consequentially, the aim of our crowdsourcing-based study is to get an inside of how lay people identify knee swelling and which measures they would adopt. Methods: Under the assumption that crowdsourcing-based methods can further develop conservative osteoarthritis treatment- in our case especially in the context of knee swelling-, a cross-sectional survey on knee swelling in osteoarthritis was carried out as part of a lecture including a workshop organised in a rural Austrian community. The 26 participants answered two open questions about characteristics and decongestant measures of knee swelling. A content structuring qualitative content analysis with a combined deductive and inductive approach followed by a frequency analysis was used to evaluate the data. Results: The participants determine knee swelling primarily based on at least one of the cardinal symptoms of inflammation (f=26), as well as an undefined optical increase in circumference (f=9). Physical (f=24), pharmacological (f=14) and complementary interventions (f=16) with partly unclear evidence are mentioned as decongestant measures. Conclusion: Identifying knee swelling and applying appropriate decongestant measures challenges lay people. Due to the deficits found, the chosen research method considering a continuous participation of lay people has the potential to further dev

Critical review of the phytohemagglutinin assay for assessing amphibian immunity.

Infectious diseases are a major driver of the global amphibian decline. In addition, many factors, including genetics, stress, pollution, and climate change can influence the response to pathogens. Therefore, it is important to be able to evaluate amphibian immunity in the laboratory and in the field. The phytohemagglutinin (PHA) assay is an inexpensive and relatively non-invasive tool that has been used extensively to assess immunocompetence, especially in birds, and more recently in amphibians. However, there is substantial variation in experimental methodology among amphibian PHA studies in terms of species and life stages, PHA doses and injection sites, and use of experimental controls. Here, we compile and compare all known PHA studies in amphibians to identify knowledge gaps and develop best practices for future work. We found that research has only been conducted on a limited number of species, which may not reflect the diversity of amphibians. There is also a lack of validation studies in most species, so that doses and timing of PHA injection and subsequent swelling measurements may not effectively evaluate immunocompetence. Based on these and other findings, we put forward a set of recommendations to make future PHA studies more consistent and improve the ability to utilize this assay in wild populations, where immune surveillance is greatly needed.