Migration Of Components Research Articles

BIOMECHANICAL ASPECTS OF IMPACTION BONE GRAFTING IN THE ACETABULAR REVISION (EXPERIMENTAL AND CLINICAL WORK)

Introduction. The modern features of the revision hip arthroplasty are the increase of the number early revisions and young age of patients. Bone defect management in this category is especially relevant. The leading role in long-term survival using impaction bone grafting (IBG) is given to the mechanical properties of the graft. The purpose of the study is to explore the mechanical properties of osteoplastic material and determine the effect of cyclic loads on dynamic changes in the position of the acetabular component after revision hip arthroplasty using (IBG). Materials and methods. A single-cycle constrained compression experiment was carried out on morselized xenobone. Cyclic tests were carried out at the second stage of the study. Clinical interpretation of biomechanics was carried out on the radiographic data by changes in the acetabular position. Results. Stress-strain dependences and instantaneous elastic moduli were obtained. The increase of the instantaneous elastic modulus during cyclic tests was obtained by 2.6 times for a “dry” specimen and from 3.9 to 4.7 times with liquid. The shift of the center rotation cranially and laterally was noted in the first case is 2.4 and 1.5 mm, in the second is 14.9 and 9.5 mm, respectively. The change in the inclination was 18.7º in the first case and 19.8º in the second. The Hip Harris Score (HHS) was 97 points in the first case, 53 points in the second. Conclusions: 1. The material used for IBG is subject to deformation in the postoperative period. 2. Compression tests suggested that the deformation of impacted bone graft in the postoperative period gradually tends to reach a plateau, and with the completion of the deformation, migration of the acetabular component stops. 3. A change of the acetabular component position in the absence of a radiolucent line is not an absolute sign of loosening.

How different soil surface treatments in urban areas affect soil pore structure and associated soil properties and processes

Soil water and temperature regimes in urban environments are greatly affected by different surface treatments, and these may lead even to changes in soil properties. The goal of this study was to find out how soil properties had changed after 8 years of soil surface modification. Five surface treatment scenarios were considered: bare soil (BS), bark chips (BC), concrete paving (CP), mown grass (MG), and unmown grass (UG). X-ray computed tomography and micromorphological analyses showed that character of pores in soils with grass (MG, UG), which were mainly influenced by organisms living in soils and roots, differed from pore character in soil covers BC or CP, which mostly were impacted by organisms living in soils. Both groups differed from BS, which was predominantly affected by the regular treatment consisting in weed removal and soil loosening. Soil under BC was more compact than for other treatments due to decomposition of the bark chips mulch and migration of mulch components. Organic matter content was greatest but its quality lowest in the BC soil, followed by UG, MG, CP, and BS. The highest aggregate stability assessed using the water-stable aggregates (WSA) index was found for UG, followed by MG, BC, CP, and BS. The greatest water retention ability was observed for BC followed by UG, MG, CP, and BS. The unsaturated hydraulic conductivities for pressure head of –2 cm measured for UG, MG, and BS were much higher than were those for CP and BC. Finally, the greatest net CO2 efflux was measured for BC and MG, followed by UG, CP, and BS. CO2 emission correlated negatively with soil physical quality expressed as slope of the soil water retention curve at its inflection point. In general, the best soil conditions were observed for UG. No treatment considerably aggravated soil condition.

Cross-Linkable Fullerene Electron Transport Layer with Internal Encapsulation Capability for Efficient and Stable Inverted Perovskite Solar Cells.

A stable and compact fullerene electron transport layer (ETL) is crucial for high-performance inverted perovskite solar cells (PSCs). However, traditional fullerene-based ETLs like C60 and PCBM are prone to aggregate under operational conditions, a challenge recently recognized by academic and industrial researchers. Here, we designed and synthesized a novel cross-linkable fullerene molecule, bis((3-methyloxetan-3-yl)methyl) malonate-C60 monoadduct (BCM), for use as an ETL in PSCs. Upon a low-temperature annealing at 100 °C, BCM undergoes in-situ cross-linking to form a robust cross-linked BCM (CBCM) film, which demonstrates excellent electron mobility and a suitable band structure for efficient PSCs. Our results show that PSCs incorporating CBCM-based ETL achieve an impressive efficiency of 25.89% (certified: 25.36%), significantly surpassing the 23.25% efficiency of PCBM-based devices. The intramolecular covalent interactions within CBCM films effectively prevent aggregation and enhance film compactness, creating an internal encapsulation layer that mitigates the decomposition and ion migration of perovskite components. Consequently, CBCM-based PSCs show exceptional stability, maintaining 97.8% of their initial efficiency after 1000 hours of maximum power point tracking, compared to only 78.6% retention in PCBM-based devices after less than 820 hours.

Analysis of potential genotoxicity of deicing material in the test for induction of dominant lethal mutations in germ cells of male Drosophila

Introduction. Long-term use of deicing materials (DM) is one of the significant factors causing the active distribution of various chemical compounds that are part of multicomponent deicing mixtures in the environment. In this regard, the expansion of methodological approaches to assessing their biological hazard remains important. Materials and methods. The DM used for research based on a mixture of urea with magnesium and ammonium nitrates. The DM was tested in the form of an aqueous solution and added to the soil to obtain an aqueous extract. The analysis includes test for induced dominant lethal mutations in Drosophila male germ cells. Results. All samples tested significantly reduced the fertility of Drosophila males. The frequencies of early dominant lethal mutations (EDLM) significantly exceeded the levels of the controls, and the effects of the soil extract appeared at the lowest concentration – 5 g/L and of the DM solution – 10 g/L. The trend in the rate of late dominant lethal mutations (LDLM) indicates to the death of sperm or a decrease in mating potency. Limitations. The method of inducing dominant lethal mutations in Drosophila melanogaster and the genotoxic effects assessment of DM in the germ cells of male flies within the study has no restrictions. Conclusion. The conducted test is so far the only one in the field of research into the genetic safety of multicomponent DMs using a method for induced dominant lethal mutations in Drosophila male germ cells. The results prove the high informative rate of the methodological approach which involves analyzing soil extracts to identify and assess a genotoxicity of DM component composition when it enters the soil which can become as a transit layer for migration of DM components and their products transformation into groundwater.

Destabilization of Pedicle Screws and Migration of Connecting Rod into the Posterior Cranial Fossa in a Patient After Posterior Spondylosynthesis with a Screw System

When performing osteosynthesis for spinal instability after traumatic injury, diagnostic difficulties arise due to the migration of metal structure components to distant “atypical” anatomical areas, which is associated with the risk of neurological deficit and life-threatening conditions. This article presents a casuistic case of migration of a metal structure component through an iatrogenic opening in the occipital bone into the posterior cranial fossa in a patient who had previously undergone instrumental correction for comminuted fractures of the cervical vertebrae. It should be noted that there are no data on “spontaneous” perforation of the occipital bone by metal osteosynthesis elements in the domestic literature.

Accuracy and precision of Volumetric Matching Micromotion Analysis (V3MA) is similar to RSA for tibial component migration in TKA.

Radiostereometric analysis (RSA) is the current gold standard to determine implant migration, but it requires bone markers and special equipment. Therefore, we developed VoluMetric Matching Micromotion Analysis (V3MA), a software program for Computed Tomography-based radiostereometric analysis (CT-RSA). This study aimed to determine the accuracy and precision of V3MA in vitro compared to RSA and provide a clinical proof of concept. The accuracy (RMSE (Root Mean Squared Error)) and precision (SD (standard deviation)) of V3MA were compared to RSA. A tibial component was placed in 21 different positions within a cadaveric bone to assess accuracy. For precision,a total of 20 repeated zero-migration examinations from 4 cadaveric bones with cemented tibial components were performed. In 6 total knee arthroplasty (TKA) patients 1 to 5 year migration was measured with V3MA and RSA. V3MA accuracy ranged between 0.02 and 0.09 mm for translations and was 0.01° for internal-external rotations. For RSA, the accuracy ranged between 0.03 and 0.09 mm for translations and was 0.09° for internal-external rotations. V3MA precision ranged between 0.01 and 0.06 mm for translations and 0.02 to 0.07° for rotations. RSA precision ranged between 0.00 and 0.06 mm for translations and 0.04 to 0.25° for rotations. V3MA was successful in 6 clinical cases and no systematic bias was present. In conclusion, the accuracy and precision of V3MA were similar to RSA. Therefore, V3MA is a promising alternative to RSA in migration measurements of tibial components in TKA.

Enhancing aesthetic outcomes: The role of biomechanics in periorbital and eyelid cosmetic surgery.

Cosmetic periorbital and eyelid surgery is a commonly performed procedure in facial plastic surgery. Understanding the biomechanics of periorbital anatomy and its role in aesthetic surgery is essential for achieving optimal outcomes. This review explores the biomechanical processes involved in periorbital age changes and analyzes the impact of cosmetic surgery approaches on these processes. By maintaining the initial mechanical equilibrium of the brows, eyelids, septal fat, and blepharoplasty folds, periorbital and eyelid cosmetic surgery can effectively rejuvenate the appearance. Disruption of this equilibrium can lead to the migration of anatomic components, resulting in signs of aging. Surgeons, by applying biomechanical concepts, can tailor the forces exerted upon the different structures to manifest the patient's aesthetic aspirations. The key to success in periorbital and eyelid cosmetic surgery lies in re-establishing a dynamic mechanical equilibrium within the periorbital framework.

Chemical elements migration in underground waters of mining territory

Relevance. The need to study the forms of migration of chemical elements in the groundwater of flooded copper pyrite mines in order to correctly understand and predict their transfer and distribution in hydrogeochemical fields. Ground and surface waters are a complex mixture of substances in which, depending on pH, Eh and t °С, phase transitions are formed with subsequent dissolution or precipitation of minerals. To solve these problems, numerical hydrogeomigration modeling is used, including physicochemical, which allows drawing conclusions about the scale of pollution and the localization of such areas for subsequent development of measures to improve the state of the hydrosphere. Aim. To determine the forms of metal migration in groundwater and to calculate water saturation indices in relation to minerals. Objects. Groundwater in the territory of the closed Levikha copper pyrite mine. Methods. Laboratory studies of groundwater were carried out using flame emission spectrometry, flame atomic absorption, photometric method with Nessler's reagent, titrimetric, mercumetric and potentiometric methods; mass spectrometry with ionization in inductively coupled plasma and gravimetric method. Physical and chemical modeling using the software product Visual MINTEQ 3.1. Results. According to the results of processing chemical analyzes and physical and chemical modeling, all tested wells are divided into groups: 1) wells no. 1, 2, 3 and 6, located within the former mining allotment (near the Levikha XIV mine, a man-made reservoir, the Levikha II mine and a neutralization station); 2) represented by water in wells no. 4 near the shaft of the mine Tsentralnaya and no. 5 near the dump Yuzhny; 3) well no. 7, located near the mouth of the Levikha river. Saturation indices and forms of migration of components in the aquatic environment make it possible to identify the scale of pollution and the localization of such areas. Thus, with the current pumping system, there is no large-scale pollution of groundwater at the Levikha mine. It is localized in the area of the Tsentralny mine shaft (well no. 4) and the Yuzhny dump (well no. 5).

Analysis and prediction for dynamic migration behavior of NEPE propellant/liner interface layer full components

The migration behavior of nitrate ester-plasticized polyether (NEPE) propellant components significantly impacts safety. Experimentally observing the migration process is challenging and time-consuming. This study employed molecular dynamics (MD) methods to simulate a molecular model of the NEPE propellant/liner interface layer, enabling the prediction of component migration behavior. We visualized the migration process of all propellant components and studied the interface layer components' migration patterns, diffusion coefficients, and concentration gradient distributions. The contents of migrated components of the propellant and liner at different accelerated aging times at 70 °C were determined using high-performance liquid chromatography (HPLC), and the simulation patterns were compared with experimental observations. The results indicate that the migrated components in the propellant mainly consist of nitrate esters (Nitroglycerin, abbreviated as NG, and Butanetriol Trinitrate, abbreviated as BTTN), stabilizers (NMethylnitroaniline, abbreviated as MNA, and 2-Nitrodiphenylamine, abbreviated as 2-NDPA), and solid component (Hexahydro-1,3,5-trinitro-1,3,5-triazine, abbreviated as RDX). The migration process is primarily dominated by the substantial migration of nitrate esters, which is a key factor contributing to the degradation of propellant performance during storage. The migration process can be divided into three stages: swift migration, steady slow migration, and migration equilibrium. The diffusion coefficients are ranked from most significant to most minor as NG > BTTN > RDX > MNA > 2-NDPA. Three migration stages consistent with the simulation process were observed using HPLC, and the migration behavior of nitrate esters aligned with simulation patterns. Our designed full-component model can qualitatively predict component migration behavior. Additionally, a faster diffusion coefficient does not necessarily lead to a greater amount of migration. We employed MD simulations combined with density functional theory (DFT) calculations to explain this phenomenon and found that intermolecular interactions may influence the diffusion coefficient. At the same time, the migration amount is highly correlated with molecular polarity. Therefore, increasing the molecular polarity difference between easily migrating components and liner materials is a beneficial strategy for slowing the migration process and enhancing the storage safety of propellants.

Delaying walnut oxidation using a compostable film comprising poly(ε-caprolactone), thermoplastic gliadins, and green tea extract

A new active packaging composed of poly(e-caprolactone) (PCL) and thermoplastic gliadin proteins incorporating green tea extract (GTE) was developed through compounding and film-extrusion process. Firstly, commercial green tea extract was analyzed, revealing that GTE primarily comprised epigallocatechin gallate (EGCG), which conferred potent antioxidant activity determined by the DPPH assay, along with moderate antibacterial activity. The incorporation of 5 wt% of GTE in the extruded films increased thermal stability and Young’s Modulus, and reduced oxygen and water vapor permeability with respect to control PCL/TPG film. Migration studies showed that the release of GTE depended on the type of food simulant, with higher levels observed in an oil-in-water emulsion simulant compared to a non-acidic aqueous food simulant, while no migration of GTE components was detected in dry foodstuffs simulant. Consequently, the antioxidant capacity derived from migrated GTE components were considerably higher in 50 % ethanol than in 10 % ethanol. Furthermore, PCL/TPG-GTE film exhibited antibacterial activity against Gram negative E. coli and Gram positive S. aureus in vitro when tested following the JIS Z2801 standard. The GTE addition also improved walnuts stability, resulting in a reduction and delay of fat peroxidation. Hence, the novel active system developed in this work can constitute a sustainable alternative to improve quality and safety of packaged products.

Degradation of toxic components in kitchen waste during hydrothermal carbonization process

Hydrothermal carbonization (HTC) is a promising technique for kitchen waste (KW) disposal. However, KW may contain heavy metals (HMs), aflatoxin, nitrites and sulfites, posing risk for hydrochar utilization. In order to clarify the migration of these toxic components during hydrochar formation process, 7 kinds of kitchen wastes were adopted to carry out HTC experiments at 180–240 °C. Concentration detections results showed that Fe, Mn, Cr, Ni, Cu, and Zn contents were relatively high with a range of 30–2500 mg/kg in KW feedstocks. After HTC treatment, Fe, Cr, Cu were mainly (>80 %) enriched in hydrochar, the enrichment factors of Mn, Ni, Zn was almost above 50 %. From the perspective of species and valence distributions, Mn, Fe, Ni, and Zn in hydrochar were below moderate risk level. No aflatoxin was detected in hydrochar, because AFB1 and AFB2 can be completely degraded into organic acids in the HTC environment at 180 °C. Part benzene rings in aflatoxin were reduced and the C-C bonds were further broken, the C-O bonds were oxidized to produce carboxylic acids. Some benzene rings in aflatoxin remained to form organic acids with aromatic structures. NO2− and SO32- ions with strong ecotoxicity were mostly converted into NO3− and SO42- and flowed into the liquid phase. Some NO2− ions were also converted to and ammonia N and pyridine N; some SO32- ions were converted to sulfonic and sulfinic acid organics, which were successively transformed into sulfonyl/sulfinyl and sulfone/sulfoxide organics. The above findings are of great significance for the transformation mechanism of toxic substances in HTC environment and environment-friendly utilization of hydrochar.

Multifunctional Sericin-Chitosan-Aloe Vera Composite Film for Food Packaging

Abstract In recent years, the demand for innovative, sustainable, and efficient food packaging solutions has surged in response to growing concerns about environmental impact, food safety, and quality preservation. A sericin-based polymer composite film with multifunctional properties shows promise as an alternative for enhancing food packaging. In this study, sericin-based composite films were prepared by incorporating Aloe vera gel, chitosan, and glycerol into a sericin solution (1.5 % w/v) through facile homogenisation at 70 °C, followed by casting and subsequent drying on a glass platform. The resulting dried film exhibited uniformity, a smooth texture, and successful integration of the composite components. The film demonstrated a moisture content of 21.02 % and a porosity of 3.56 %, with a thickness of (62.1 ± 2.3) µm. It exhibited moderate transparency with reasonable water vapour permeability. Notably, the DPPH scavenging results indicated that the film has a potent antioxidant capacity with an efficacy rate of 99.1 %, supported further by a phenolic content of 11.5 mg GAE per gram of film. Controlled solute migration of components from the composite films was observed, particularly under acidic conditions. Importantly, toxicity evaluation on A549 cells revealed no adverse effects, even at higher concentrations. Due to its consistent film-forming ability, antioxidant potency, controlled migration, and safe nature, the developed sericin polymer-based film could be an effective alternative for food packaging sensitive foods, maintaining oxidative stability, reducing moisture loss, improving quality, and extending shelf life.

Fluid-rock interaction related to alpine subduction of Allalingabbro deduced from large-size μXRF element maps

Alpine subduction of a block of olivine gabbro produced a plethora of different assemblages and local structures typical of high-pressure and low-temperature metamorphism. However, gabbro with the locally well-preserved igneous assemblage olivine - augite - plagioclase occurs in some domains of a 2 km long outcrop (Allalinhorn, western Alps).A large variety of hydrate minerals including zoisite, glaucophane, talc, Mg-chloritoid, chlorite, paragonite and muscovite formed during Alpine subduction of the metagabbro. The three primary igneous minerals have been replaced by hydration reactions during Eocene subduction. Talc, omphacite, and zoisite + jadeite and are the main minerals in the local domains after olivine, augite and plagioclase respectively. The rocks preserved the coarse grained igneous texture.An excellent overview of the complex coarse textures of the eclogite facies rocks has been provided by element distribution maps produced from up to 25 cm large polished slabs of typical samples of Allalingabbro using a μXRF instrument. The RGB images suggest that the minerals formed at the high-pressure in the presence of an aqueous fluid. The pseudomorphing reactions progressed close to volume conservation. The hydration reactions required an H2O fluid containing dissolved solids. The mapped distribution of elements including trace elements provides important clues on the origin and mobility of these elements in the hydration fluid. The homogeneously distributed immobile Cr in omphacite portrays primary augite. The irregular patchy Sr distribution resulted from small-scale migration of components replacing plagioclase by Sr-bearing zoisite and jadeite. Coherent Ni signals are related to the presence of talc. The talc occurs as a late infill of structures produced by dissolving olivine. Mg-chloritoid, kyanite and mica coat the former grain-boundary of olivine and plagioclase suggesting that olivine dissolved at eclogite facies conditions. Talc formed at distinctly lower pressures, however, as implied by computed model reactions. The olivine replacement structures are often larger than the size thin section and can be excellently studied by the large size μXRF patterns used in this study.The fractured surroundings of the locations of olivine provided the necessary hydraulic conductivity for hydration reactions to progress. The fractures and small veinlets contain late Ni-bearing talc. Cl is only present in very late vein amphibole suggesting that hydration fluids in the subduction zone transported dissolved components as hydrous complexes (and their dissociated ions). There is no evidence for the presence of a Cl-brine during subduction. In addition to primary olivine as a local Ni source, the element may also have partly been imported with the hydration fluid and originate from dehydration of ophiolitic serpentinites in the slab.

A PROSPECTIVE RANDOMIZED CONTROLLED TRIAL COMPARING THE DIRECT SUPERIOR APPROACH WITH THE POSTERIOR APPROACH FOR TOTAL HIP ARTHROPLASTY

The direct superior approach (DSA) is a modification of the posterior approach (PA) that preserves the iliotibial band and short external rotators except for the piriformis or conjoined tendon during total hip arthroplasty (THA). The objective of this study was to compare postoperative pain, early functional rehabilitation, functional outcomes, implant positioning, implant migration, and complications in patients undergoing the DSA versus PA for THA.This study included 80 patients with symptomatic hip arthritis undergoing primary THA. Patients were prospectively randomised to receive either the DSA or PA for THA, surgery was undertaken using identical implant designs in both groups, and all patients received a standardized postoperative rehabilitation programme. Predefined study outcomes were recorded by blinded observers at regular intervals for two-years after THA. Radiosteriometric analysis (RSA) was used to assess implant migration.There were no statistical differences between the DSA and PA in postoperative pain scores (p=0.312), opiate analgesia consumption (p=0.067), and time to hospital discharge (p=0.416). At two years follow-up, both groups had comparable Oxford hip scores (p=0.476); Harris hip scores (p=0.293); Hip disability and osteoarthritis outcome scores (p=0.543); University of California at Los Angeles scores (p=0.609); Western Ontario and McMaster Universities Arthritis Index (p=0.833); and European Quality of Life questionnaire with 5 dimensions scores (p=0.418). Radiographic analysis revealed no difference between the two treatment groups for overall accuracy of acetabular cup positioning (p=0.687) and femoral stem alignment (p=0.564). RSA revealed no difference in femoral component migration (p=0.145) between the groups at two years follow-up.There were no differences between patients undergoing the DSA versus PA for THA with respect to postoperative pain scores, functional rehabilitation, patient-reported outcome measurements, accuracy of implant positioning, and implant migration at two years follow-up. Both treatment groups had excellent outcomes that remained comparable at all follow-up intervals.

Five-year migration of uncemented femoral components in total knee arthroplasty with either highly cross-linked or conventional polyethylene inserts: a blinded randomized controlled trial using radiostereometric analysis.

The aim of this study was to compare the migration of the femoral component, five years postoperatively, between patients with a highly cross-linked polyethylene (HXLPE) insert and those with a conventional polyethylene (PE) insert in an uncemented Triathlon fixed insert cruciate-retaining total knee arthroplasty (TKA). Secondary aims included clinical outcomes and patient-reported outcome measures (PROMs). We have previously reported the migration and outcome of the tibial components in these patients. A double-blinded randomized controlled trial was conducted including 96 TKAs. The migration of the femoral component was measured with radiostereometry (RSA) at three and six months and one, two, and five years postoperatively. PROMs were collected preoperatively and at all periods of follow-up. There was no clinically relevant difference in terms of migration of the femoral component or PROMs between the HXLPE and PE groups. The mean difference in migration (maximum total point motion), five years postopeatively, was 0.04 mm (95% CI -0.06 to 0.16) in favour of the PE group. There was no clinically relevant difference in migration of the femoral component, for up to five years between the two groups. These findings will help to establish a benchmark for future studies on migration of femoral components in TKA.

Liquefaction efficiency study of heterogeneous condensation of methane-ethane binary gas mixtures with different component contents

Natural gas is a mixture of hydrocarbons. During the liquefaction of natural gas, the mixed gas undergoes heterogeneous condensation on the surface of the heat exchanger. Currently, the heterogeneous condensation mechanism of mixed gases is not fully understood, and the influence of component content on the liquefaction efficiency is not clear. Therefore, the molecular dynamics simulation was employed to investigate the heterogeneous condensation process of methane-ethane binary mixed gas on a solid surface. The characteristics of condensation nucleation cluster growth was explored and the variations in temperature, density, heat flux, and liquefaction rate were analyzed. The impact of ethane on methane condensation was also discussed. The results indicate that increasing wettability enhances surface nucleation quantity and shortens nucleation time, resulting in a 3.6- times increase in heat flux. The addition of ethane gas in the system promotes condensation nucleation, which increases the liquefaction rate by 60 % when x = 20 % compared to the pure methane system. However, for methane gas, ethane only benefits the liquefaction of methane molecules in the initial nucleation stage. As the mixture in the system enters the cluster growth stage, component migration in the mixed gas leads to a lower liquefaction rate compared to pure methane gas.

Multiscale evaluation of aging susceptibility of asphalt binders modified with recycled rubber and plastic pyrolytic oil composites

Changes in rheological performance, migration of chemical components, and microstructure transformation are some of the processes that occur as asphalt binders age across various stages throughout their lifecycle. Aging-related changes influence pavement performance, typically increasing its susceptibility to issues like fatigue and thermal cracking. Thus, comprehending the role of aging in the performance of asphalt binders is vital for devising effective pavement design and maintenance strategies. The use of plastic pyrolysis oil and recycled non-tire automobile rubber to create oil-rubber modified asphalt binders is becoming quite popular as a sustainable and environmentally friendly method for asphalt pavements. This study aimed to assess the aging behavior of asphalt binders modified with plastic pyrolysis oil and recycled non-tire automotive rubber, both separately and in composite modification. Binders underwent testing under four aging conditions: unaged, short-term aged, long-term aged, and extended long-term aged. The study focused on a multiscale assessment of aging characteristics, encompassing macroscale, mesoscale, microscale, and nanoscale analyses. At the macroscale, the binders were tested for rheological parameters using multiple stress creep recovery (MSCR), linear amplitude sweep (LAS), and Glover-Rowe (G-R) parameter tests, while the mesoscale analysis was conducted using Fourier-transform infrared (FTIR) spectroscopy. Additionally, microstructural analysis was performed using atomic force microscopy (AFM), and nanoscale evaluation was carried out using nuclear magnetic resonance (NMR). Finally, a comprehensive assessment index that included all the parameters under study was generated using radar graph analysis. It was observed that modifying an asphalt binder with a heat-preheated composite of plastic pyrolysis oil and recycled non-tire automotive rubber showed the lowest CAI values, thus helping to mitigate the effects of aging and achieving enhanced binder performance.

Active Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) Films Containing Phenolic Compounds with Different Molecular Structures.

To obtain more sustainable and active food packaging materials, PHBV films containing 5% wt. of phenolic compounds with different molecular structures (ferulic acid, vanillin, and catechin) and proved antioxidant and antimicrobial properties were obtained by melt blending and compression molding. These were characterized by their structural, mechanical, barrier, and optical properties, as well as the polymer crystallization, thermal stability, and component migration in different food simulants. Phenolic compounds were homogenously integrated within the polymer matrix, affecting the film properties differently. Ferulic acid, and mainly catechin, had an anti-plasticizing effect (increasing the polymer glass transition temperature), decreasing the film extensibility and the resistance to breaking, with slight changes in the elastic modulus. In contrast, vanillin provoked a plasticizing effect, decreasing the elastic modulus without notable changes in the film extensibility while increasing the water vapor permeability. All phenolic compounds, mainly catechin, improved the oxygen barrier capacity of PHBV films and interfered with the polymer crystallization, reducing the melting point and crystallinity degree. The thermal stability of the material was little affected by the incorporation of phenols. The migration of passive components of the different PHBV films was lower than the overall migration limit in every simulant. Phenolic compounds were released to a different extent depending on their thermo-sensitivity, which affected their final content in the film, their bonding forces in the polymer matrix, and the simulant polarity. Their effective release in real foods will determine their active action for food preservation. Catechin was the best preserved, while ferulic acid was the most released.

Glenoid structural bone grafting in reverse total shoulder arthroplasty: clinical and radiographic outcomes

IntroductionCurrent options for reconstruction of large glenoid defects in reverse total shoulder arthroplasty (RTSA) include structural bone grafting, utilization of augmented components, or 3D printed custom implants. Given the paucity in the literature on structural bone grafts in RTSA, this study reflects our experience on clinical and radiographic outcomes of structural bone grafts utilized for glenoid defects in RTSA. MethodsWe identified 33 consecutive patients who underwent RTSA utilizing structural bone grafts for glenoid bone loss between 2008 and 2019. Twenty-six patients with mean clinical follow-up of 4.4 ± 3.9 years and mean radiographic follow-up of 2.7 ± 3.2 years were included. Patient demographic data, peri-operative functional outcomes, radiographic outcomes, complications, and re-operation rates were determined. ResultsBetween 2008 and 2019, 26 RTSAs were performed utilizing structural autograft or allograft for glenoid defects. There were 20 females (77%) and 6 males (23%), with mean presenting age of 68 years (range 41-86), mean BMI of 29 (range 21-44) and mean Charlson Comorbidity Index of 3 (range 0-8). There were 19 cases of central glenoid defects, and 7 were combined central and peripheral defects. Structural grafts included humeral head autograft (7), proximal humerus autograft (7), iliac crest autograft (7), distal clavicle autograft (2), and femoral head allograft (3). All eighteen revision RTSA cases had simultaneous humeral-sided revision. There was significant postoperative improvement in ASES scores (27.0 ± 12.6 preop vs. 59.8 ± 24.1 postop; p<0.001) and VAS scores (8.1 ± 3.6 preop vs. 3.0 ± 3.2 postop; p<0.001). Range of motion improved significantly for active forward elevation (63 ± 36º preop vs. 104 ± 36º postop; p<0.001) and external rotation (21 ± 20º preop vs. 32 ± 23º postop, p=0.036). Eighty-eight percent (23/26) of cases had successful reconstruction of the glenoid, defined as no visible radiolucent lines nor glenoid component migration at final follow-up. Re-operation rate was 19% (5/26) Postoperative complications included 2 cases of acromial stress fractures that were treated non-operatively, for a total complication rate (including re-operation) of 27% (7/26 cases). ConclusionsThe use of structural bone autografts and allografts in RTSA was associated with improved outcome scores and range of motion. A reoperation rate of 19% and total complication rate of 27% were reported for these challenging cases. However, 86% of these complications were not related to structural glenoid reconstruction failure. Structural grafts are a reasonable option for glenoid reconstruction in RTSA cases with glenoid bone loss.

Influence of acidity and alkalinity of water environment on water stability of asphalt mixture: Phase II-microscopic erosion mechanism

Acidity and alkalinity of water environments have been proven to influence the water stability of asphalt mixture. However, the relevant influencing mechanism still remains unclear. To fulfill this research gap, this study conducted a series of microscopic tests, aiming at unveiling the microscopic erosion mechanism of the water environment on the water stability of asphalt mixture for better moisture stability achieved. Specifically, the asphalt-aggregate interfacial transition zone (ITZ) samples were prepared by combining #70 asphalt with limestone and granite, respectively, which were then immersed in water solutions at 3 different pH levels (pH = 3.0, 7.0, and 11.0) for 7 days. The chemical composition and microstructure of the asphalt film on the surface of the ITZ samples pre and post-treatment were scrutinized using the Fourier Transform Infrared Spectroscopy (FTIR) and the Atomic Force Microscope (AFM), while the development of microcracks at the asphalt-aggregate interface were identified and traced utilizing the Scanning Electron Microscope (SEM). The test results indicate that after treatment with acidic and alkaline aqueous solutions, the asphalt film's surface is enriched with polar components such as asphaltenes, resins, and aromatic fractions. The migration of these polar components to the surface of the asphalt film reduces the adhesion between asphalt-aggregate, leading to the formation of microcracks at the asphalt-aggregate interface. The most severe crack development occurs in alkaline water environment, followed by acidic water environment. It is interestingly noted that the adhesion at the asphalt-granite interface is improved under the acidic environment. This improvement may be attributed to the covalent nature of silica, which hinders the adsorption of ions from acidic solution into the asphalt film. This hindrance effectively prevents water intrusion at the asphalt-aggregate interface, thereby reducing the adhesion loss. These findings can help elucidate the mechanism of water damage in asphalt pavement exposed to real-world conditions and enhance its water stability with effective countermeasures proposed.