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In this contribution, we employ computational tools from the energy landscape approach to test Gaussian Approximation Potentials (GAPs) for C60. In particular, we apply basin-hopping global optimization and explore the landscape starting from the low-lying minima using discrete path sampling. We exploit existing databases of minima and transition states harvested from previous work using tight-binding potentials. We explore the energy landscape for the full range of structures and pathways spanning from the buckminsterfullerene global minimum up to buckybowls. In the initial GAP model, the fullerene part of the landscape is reproduced quite well. However, there are extensive families of C1@C59 and C2@C58 structures that lie lower in energy. We succeeded in refining the potential to remove these artifacts by simply including two minima from the C2@C58 families found by global landscape exploration. We suggest that the energy landscape approach could be used systematically to test and improve machine learning interatomic potentials. [ABSTRACT FROM AUTHOR]

This work deals with the stochastic inference of gas-phase chemical reaction rates in high temperature air flows from plasma wind tunnel experimental data. First, a Bayesian approach is developed to include not only measurements but also additional information related to how the experiment is performed. To cope with the resulting computationally demanding likelihood, we use the Morris screening method to find the reactions that influence the solution to the stochastic inverse problem from a mechanism comprising 21 different reactions for an air mixture with seven species: O2, N2, NO, NO+, O, N, e−. A set of six reactions, mainly involving nitrogen dissociation and exchange, are the ones identified to impact the solution the most. As such, they are assumed to be uncertain and estimated along with the boundary conditions of the experiment and the catalytic recombination parameters of the materials involved in the testing. The remaining 15 reactions are set to their nominal values. The posterior distribution is then propagated through the proposed boundary layer model to produce the posterior predictive distributions of the temperature and mass fraction profiles along the boundary layer stagnation line. It is identified that NO concentrations have the largest increase in uncertainty levels compared to cases where the inference problem is carried out for fixed chemical model parameter values. This allows us to inform a new experimental campaign targeting the reduction of uncertainties affecting the chemical models. [ABSTRACT FROM AUTHOR]

With increasing demand and environmental concerns, researchers are exploring new materials that can perform as well or better than traditional materials while reducing environmental impact. The BAMline, a real-life sample materials research beamline, provides unique insights into materials' electronic and chemical structure at different time and length scales. The beamline specializes in x-ray absorption spectroscopy, x-ray fluorescence spectroscopy, and tomography experiments. This enables real-time optimization of material properties and performance for various applications, such as energy transfer, energy storage, catalysis, and corrosion resistance. This paper gives an overview of the analytical methods and sample environments of the BAMline, which cover non-destructive testing experiments in materials science, chemistry, biology, medicine, and cultural heritage. We also present our own synthesis methods, processes, and equipment developed specifically for the BAMline, and we give examples of synthesized materials and their potential applications. Finally, this article discusses the future perspectives of the BAMline and its potential for further advances in sustainable materials research. [ABSTRACT FROM AUTHOR]

Novel photonic nanowires are fabricated using low‐index materials and tested in the near‐infrared spectrum to assess their nonlinear optical properties. In this work, the need to redefine the standard nonlinear figure of merit in terms of nonlinear phase shift and optical transmission for a given propagation distance is argued. According to this new metric, the devices largely outperform all established platforms for optical modules with a linear footprint in the range of 50–500 µm, which is demonstrated to be an outstanding technological gap. For 85 fs pulses, with carrier wavelength at 1480 nm and sub‐µW power levels, a spectral broadening exceeding 80% of the initial bandwidth was recorded over a propagation length of just 50 µm. Leveraging on CMOS‐compatible processes and well‐established materials such as silicon, silica, and indium tin oxide, the devices bring great promise for developing alternative all‐optical devices with unparalleled nonlinear performances within the aforementioned range. [ABSTRACT FROM AUTHOR]

The racecourse "Kerepesi Ügető" in Budapest was closed in 2000, and all of its buildings were demolished except for the Class II Grandstand, which had been declared a national monument earlier. Our task was to perform a comprehensive static investigation of this grandstand and to develop a methodology for structural strengthening in order to preserve this monument for future generations. Investigations included in situ measurements, laboratory material tests, and finite‐element analysis of the structure. According to the results of static calculations, the method of strengthening was proposed, which included the injection of cracks, integration of new structural elements, application of concrete jacketing, and bonded carbon‐fiber‐reinforced polymer sheets. The applied strengthening and renovation method extended the lifespan of the grandstand by 50 years. [ABSTRACT FROM AUTHOR]

In this study, the functionality of self‐formulated carbon‐based conductive coatings (CBCCs) with incorporation of graphite as the anode in an impressed current cathodic protection system is studied. The anode materials are tested and evaluated for long‐term durability and performance by an accelerated durability test method. The results show that the functional time is highly dependent on the acceleration factor, and thus the charge passed through the material during testing, as well as the material composition. From the results, there are also indications that the addition of graphene into the CBCC matrix has a positive effect on the homogeneity of the material, but without any major influence on the conductivity and performance. [ABSTRACT FROM AUTHOR]

Fragrance encapsulates are widely used in consumer care applications such as fabric softeners or other liquid laundry products; they provide multiple benefits, from fragrance protection in the commercial product to a controlled release and improved sensorial experience for the consumers. Polymeric fragrance encapsulates are in the scope of the EU regulation restricting the use of intentionally added microplastic particles, and industry is actively working on innovation programs to find biodegradable alternatives. However, particular attention needs to be paid to claims that a fragrance encapsulation system is biodegradable, because biodegradation test results can vary considerably depending on how a test material is prepared, which can even lead to false‐positive biodegradation test results, as shown in our study. We demonstrate the importance of the sample preparation phase of the process. We show how the biodegradation level can fluctuate from 0% to 91%, depending on how the test material is isolated from a given microcapsule slurry system, and we present a method that can be used to obtain trustworthy biodegradation results. Environ Toxicol Chem 2024;43:1242–1249. © 2024 Givaudan France SAS. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Amputees who use prosthetic limbs suffer from the problem of high contact temperature between the socket of the prosthetic limb and the amputated part and lack of evaporation of sweat. These conditions lead to discomfort and failure to perform functions properly. In addition, these conditions help generate ulcers and accumulate harmful bacteria in this area. This paper presents a heatsink design to extract heat from the contact area. A cylindrical heat sink is designed for phase‐changing materials with three branched tubes in two stages. The current heat sink is used to cool the contact area between the amputated part and the socket in the lower prostheses. Three distributions of pipe branches are proposed. The distribution and pipe lengths were obtained using a constructal design method. In the constructal design, the lengths of the branched tubes were the degrees of freedom, the objective function was the minimization of the inlet temperature to the heat sink, and the constraint was the volume of the cylindrical heat sink. The metabolic heat transfer during exercise was estimated and its value was used to calculate the size of the cylindrical heatsink and the selection of the phase change material by testing three of them: water, tridecane, and dodecane. It was found that water gives the highest latent heat of melting and the lowest volume in addition to its availability. On the other hand, two cooling fluids were tested: water and air. It was found that water as a cooling fluid gave the lowest flow and the largest heat capacity. Constructal theory was used to design a cylindrical heat sink using branched tubes for the coolant in two steps: the first with three branches, and the second with nine branches. The degree of freedom for constructal theory was the length of the branches through the choice of their end locations. It was found that the branches of the highest length led to a reduction in temperature from 40°C to 15.48°C compared with the single tube, which reduced the temperature to 23.87°C. All tests recorded a pressure drop within the acceptable range of 3.1–5.43 Pa for the branches examined. The research demonstrated that using constructal theory achieved the best thermal dissipation within a restricted volume. [ABSTRACT FROM AUTHOR]

This study aimed at examining the bond strength between zirconia and ceramic veneer, following the ISO 9693 guidelines. A total of fifty specimens of zirconia/ceramic‐veneer system were produced using two commercial zirconias (VITA YZ‐HTWhite and Zolid HT+ White, referred to as Group A and Group B, respectively) and a ceramic‐veneering material (Zirkonia 750). The microstructure (via x‐ray diffraction analysis, XRD and Secondary Electron mode, SEM) and the mechanical properties (via 3‐point bending tests) of the two groups were assessed. Then, experiments were conducted according to the ISO 9693 and conventional protocols applied for producing zirconia/ceramic‐veneer restorations. Bond strength values, measured by 3‐point bending tests, were 34.42 ± 7.60 MPa for Group A and 31.92 ± 6.95 MPa for Group B. SEM observations of the cohesively fractured surfaces (on the porcelain side) and the examination for normality using the Shapiro–Wilk test suggested the use of Weibull statistical analysis. Median strength (σ50%) for Group A and Group B was 34.76 and 32.22 MPa, while the characteristic strength (σ63.2%) was 35.78 and 33.14 MPa, respectively. The Weibull modulus disparity between groups (12.69 and 13.07) was not significant. Bond strength exceeded the ISO 9693 minimum of 20 MPa, suggesting satisfactory strength for clinical use. [ABSTRACT FROM AUTHOR]

Resin‐based three‐dimensional (3D) printing finds extensive application in the field of dentistry. Although studies of cytotoxicity, mechanical and physical properties have been conducted for newly released 3D printing resins such as Crowntec (Saremco), Temporary Crown Resin (Formlabs) and Crown & Bridge (Nextdent), the resistance of these materials to esterases in saliva has not been demonstrated at the molecular level. Therefore, in this study, the binding affinities and stability of these new 3D printing resins to the catalytic sites of esterases were investigated using molecular docking and molecular mechanics with Poisson–Bolzmann and surface area solvation (MM/PBSA) methods after active pocket screening. Toxicity predictions of the materials were also performed using ProTox‐II and Toxtree servers. The materials were analyzed for mutagenicity, cytotoxicity, and carcinogenicity, and LD50 values were predicted from their molecular structures. The results indicated that out of the three novel 3D printing materials, Nexdent exhibited reduced binding affinity to esterases, indicating enhanced resistance to enzymatic degradation and possessing a superior toxicity profile. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effect of four different strategies for bonding a CAD/CAM resin nanoceramic restoration (Lava Ultimate, 3M) to the dentin surface using a universal adhesive (Scotch Bond Universal, 3M) and adhesive resin cement (RelyX Ultimate, 3M) on the shear bond strength (SBS) and failure mode. The strategies comprised: (i) immediate sealing, immediate bonding; (ii) immediate sealing, bonding after 2 weeks with provisional restoration; (iii) immediate sealing with flowable resin composite reinforcement and bonding after 2 weeks with provisional restoration; and (iv) no immediate sealing, and bonding after 2 weeks with provisional restoration. After bonding, all the specimens were thermocycled, shear tests were performed using a universal testing machine, and failure modes were determined using stereomicroscope and scanning electron microscopy. The highest mean SBS was recorded with immediate sealing, immediate bonding strategy. Most adhesive failures with exposed dentinal tubules were noted in specimens exposed to bonding after 2 weeks with no immediate sealing, which was associated with the lowest SBS. Mixed failures predominated in all immediate dentin sealing groups. Immediate sealing with universal adhesives improves SBS, particularly in the single‐visit approach, which has shown significantly better performance, whereas the provisional phase has a negative effect. [ABSTRACT FROM AUTHOR]

As the quest for long-term lunar exploration and habitation comes closer to reality, widespread efforts are ongoing to effectively mitigate lunar dust surface contamination and infiltration. This dust is hazardous to humans and tends to adhere tenaciously to all exposed surfaces, causing performance issues and ultimately failure. While several active and passive technologies have been developed to address this challenge, assessing the performance of these technologies in the lunar environment is required. The Regolith Adherence Characterization experiment payload scheduled to be flown to the lunar surface in 2024 provides an important opportunity for this evaluation. A limited number of material testing slots were available to the NASA Langley Research Center for this mission, so it was critical to make an informed selection. Two polymers, Kapton® HN and Teflon™ FEP, a carbon fiber reinforced bismaleimide composite, and a titanium alloy, Ti–6Al–4V, were chosen to be a diverse selection of structural materials from the NASA Langley Research Center. Each material was topographically modified using laser ablation patterning. This article describes the selection, surface modification, terrestrial characterization, and performance evaluation for these passive dust mitigating materials. • Lunar dust is a significant challenge for long term missions on the Moon. • The fine dust is specially jagged, highly abrasive and clings strongly to exposed surfaces. • The contamination of components with this dust can cause failure. • In this work, materials were selected, and surface engineered for minimizing simulated lunar dust adhesion. • They were then integrated into a payload for dust adhesion evaluation on the Moon in 2024. [ABSTRACT FROM AUTHOR]

Carbon dioxide capture and reduction (CCR) process emerges as an efficient catalytic strategy for CO 2 capture and conversion to valuable chemicals. K-promoted Cu/Al 2 O 3 catalysts exhibited promising CO 2 capture efficiency and highly selective conversion to syngas (CO + H 2). The dynamic nature of the Cu-K system at reaction conditions complicates the identification of the catalytically active phase and surface sites. The present work aims at more precise understanding of the roles of the potassium and copper and the contribution of the metal oxide support. While γ-Al 2 O 3 guarantees high dispersion and destabilisation of the potassium phase, potassium and copper act synergistically to remove CO 2 from diluted streams and promote fast regeneration of the active phase for CO 2 capture releasing CO while passing H 2. A temperature of 350℃ is found necessary to activate H 2 dissociation and generate the active sites for CO 2 capture. The effects of synthesis parameters on the CCR activity are also described by combination of ex-situ characterisation of the materials and catalytic testing. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the effects of different surface treatments on the repair bond strength between a fiber‐reinforced dentin composite and a posterior composite. Methods: Forty fiber‐reinforced dentin composite resin blocks (4 mm × 4 mm × 4 mm) were separated into eight groups (n = 5) according to the surface preparation methods: (G1) negative control group, (G2) adhesive application, (G3) 50% dimethylsulfoxide (DMSO) application, (G4) 50% DMSO + adhesive application, (G5) 37% phosphoric acid etch + adhesive application, (G6) air abrasion + adhesive application, (G7) 37% phosphoric acid etch + 50% DMSO application + adhesive application, and (G8) air abrasion +50% DMSO application + adhesive application group. The composite surfaces were repaired in two layers with a posterior composite. Composite sticks were subjected to a micro tensile bond strength (μTBS) test. Fractured surfaces were evaluated using a stereomicroscope (×25). Short fiber‐reinforced composite samples' surfaces were investigated by scanning electron microscope (SEM). Shapiro Wilk, one‐way ANOVA, and Tukey HSD tests were used for statistical evaluation. Results: The highest average (μTBS) values were observed in G8, whereas the lowest mean μTBS values were evident in the G1 group. Statistically significant μTBS values were found in all adhesive‐applied groups when compared with the negative control group. Notably, the application of 50% DMSO without adhesive did not lead to a statistically significant increase in μTBS values. SEM images demonstrated that acid etching partially eliminated residues on the composite surface, while air abrasion had a detrimental effect on the integrity of fiber structures. Conclusion: In the repair of fiber‐reinforced dentin composite with a posterior composite, adhesive application is an effective approach. The treatment of 50% DMSO without adhesive did not confer a statistically significant advantage, and the supplemental use of acid etch or air abrasion did not show an additional benefit compared to adhesive‐only repairs. Clinical Significance: Adhesive application emerges as a potent and effective strategy for the repair of bur‐roughened fiber‐reinforced dentin composites. With its limitations, the study highlights the efficacy of adhesive‐only repairs without the necessity for additional surface treatments. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate surface microhardness and gingival marginal adaptation of three different bulk‐fill flowable resin composites (FB‐RBCs) in Class V cavities with enamel or dentin margins before and after thermocycling (TMC). Materials and Methods: Three available FB‐RBCs were used; Palfique Bulk Flow (PaBF) (Tokuyama Dental), SDR Flow+ Bulk Fill Flowable (Dentsply Sirona), and I‐Flow Bulk Fill (I‐Dental). Thirty discs were prepared from each type of FB‐RBCs. The discs were subjected to Vickers microhardness tester machine. Class V cavities were prepared on 180 molars. Gingival margins of half the specimens were prepared above CEJ and the other half below CEJ. Cavities were restored with FB‐RBCs for gingival marginal adaptation test. Two‐way ANOVA was used in microhardness, while three‐way ANOVA was used for marginal adaptation. Results: The used materials showed statistically significant differences in microhardness and marginal adaptation. Conclusions: Regarding microhardness, PaBF showed the highest value before TMC and SDR was the highest after TMC. Regarding marginal adaptation, SDR revealed the best marginal adaptation than PaBF and I‐flow, either subjected to TMC or not. Clinical Significance: The longevity of cervical restorations depend on both the location of the cavity margin and the material used. The microfractures in resin composite surface due to low surface microhardness as well as marginal gaps seen in laboratory studies could be considered as an indicative parameter for clinical problem associated with marginal differences. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of cumulative doses of radiation on the pushout bond strength (BS) of a universal resin cement used in the self‐etch (SE) and self‐adhesive (SA) modes to the intraradicular dentin. Materials and Methods: Forty‐eight human teeth were distributed into three groups (n = 16) according to the radiation therapy dose (RT): NoRT (no‐radiotherapy), 70RT (70 Gy), and 70 + 70RT (70 Gy + 70 Gy). The teeth were redistributed into two subgroups (n = 8), according to the adhesive mode: SE (NoRT‐SE, 70RT‐SE, and 70 + 70RT‐SE) and SA (NoRT‐SA, 70RT‐SA, and 70 + 70RT‐SA). Data were statistically compared after BS test (ANOVA, Tukey's post hoc test, and Fisher's exact test). Results: In the SA mode, BS was significantly higher in nonirradiated teeth compared with 70RT and 70 + 70RT (p < 0.0001). There were no significant differences between SE and SA modes in nonirradiated teeth (p = 0.14). In the 70RT group, SE mode increased BS compared with SA mode (p < 0.0001). Most specimens had adhesive and mixed failures in SA and SE modes, respectively. Conclusions: The universal resin cement in the SE mode had greater BS to the irradiated dentin. When teeth were re‐irradiated, the universal resin cement had similar performance in terms of BS, regardless of the adhesive approach. Clinical Significance: There is no research establishing a correlation between radiotherapy and its impact on the BS of a universal resin cement used in SE and SA modes to intraradicular dentin. [ABSTRACT FROM AUTHOR]

To assess the physical properties and topographical aspect of dental enamel's surface microhardness (KHN), surface roughness (Ra), and color parameters CIELAB (∆Eab*), CIEDE 2000 (∆E00), and whiteness index for dentistry (∆WID) after toothbrushing with experimental toothpaste formulations with the following mineral clay types: kaolin, Sparclay SGY, and Tersil CGY used as abrasive component. Scanning electron microscopy (SEM) was performed for topographical analyses purposes. A total of 96 bovine incisors were used in the experiment. They were divided into eight experimental groups (n = 12), namely: NC—negative control (no treatment), CT12—Colgate Total 12®, CMP—Colgate® Máxima Proteção Anticáries, K—kaolin experimental toothpaste, SGY—Sparclay SGY experimental toothpaste; CGY—Tersil CGY experimental toothpaste, SD—SiO2 experimental toothpaste, and CC—CaCO3 experimental toothpaste. All samples were subjected to mechanical brushing protocol with 5000 cycles and kept in artificial saliva with daily exchanges. KHN was analyzed through the mixed linear model for repeated measures over time. Ra was analyzed through nonparametric Kruskal Wallis and Dunn tests to compare the groups. Paired Wilcoxon test was run to compare experimental times. ∆WID, ∆Eab*, and ∆E00 were analyzed through Kruskal Wallis and Dunn tests. All analyses were performed in R* software, at 5% significance level. EXP_SGY recorded higher KHN than EXP_SiO2 and EXP_CaCO3, whereas EXP_K showed increased Ra in comparison to CMP (p = 0.0229). ∆Eab and ∆E00 were significantly higher in the CT12, EXP_SiO2, and EXP_CaCO3 groups than in the NC and EXP_K (p < 0.0001). There were no significant changes in ∆WID (p = 0.0852). According to SEM results, toothbrushing with experimental toothpastes added with mineral clay types did not have significant impact on enamel's polishing and smoothness. Clinical Relevance: Mineral clays have a broad application in the cosmetic industry, and recently, they have been used in the formulation of vegan toothpaste. [ABSTRACT FROM AUTHOR]

Developing a reliable and robust finite element model of a carbon fiber-reinforced plastic (CFRP) composite structure is investigated by using the LS-DYNA solver and Python. This study tries to provide a systematic numerical approach to cover the principal impediment to adaptation of composite energy absorbers, that is the lack of a reliable predictive method. The proposed procedure aims to further the understanding of advanced composite structures' behavior during the crash phenomenon by developing an accurate finite element model. To do so, the mechanical properties of the material were extracted from American Society for Testing and Materials (ASTM) standard test methods, followed by experimental investigation of circular CFRP tubes undergoing quasi-static loading. A numerical simulation framework was then utilized to scrutinize the effectiveness of simulation parameters on the crushing mechanism. Finally, a systematic approach based on machine learning techniques was performed to adjust non-physical modeling parameters for further calibration and validation. In this regard, a versatile Python code was developed to automate pre-processing, processing, and post-processing steps. The code also provides a groundwork to perform machine learning techniques. Interestingly, the numerical and experimental results were highly correlated with a correlation coefficient of almost 90%. Additionally, several non-physical numerical parameters were found to be inactive, while some else were identified as effective parameters, and their corresponding effectiveness was quantitatively extracted and discussed for the first time in the literature. [ABSTRACT FROM AUTHOR]

Metamaterials have drawn interest in the sensor community due to their extreme dielectric-sensitive resonant behavior. Although these structures are studied in a wide range of frequencies, the ultrahigh frequencies are of special interest due to their compatibility with RF electronics. Unlike spectroscopic methods, where each material has its specific fingerprint, the response of these resonant structures depends on the electromagnetic properties, the volume of the material under test, and the resonator's design itself. Thus, implementing a metamaterial-based sensor for biological and chemical applications requires some mechanism to fix the sample's location and volume. Since most biological and chemical samples are liquids, microfluidics is the most promising candidate for this task. Here, we propose a dielectric sensing platform with a cost-effective fabrication method that allows fluid detection inside the microfluidic channel. The device proposed here is designed numerically, fabricated and measured, and finally validated via an analytical lumped model. It consists of a microstrip line coupled with a split ring resonator as the transducer and a microfluidic structure to control the sample and generate microdroplets. The fluid under test inside the microfluidic channel can be characterized based on the change in its dielectric constant or loss factor. The device shows a 600 kHz resonance shift in response to the dielectric change in sample volumes as low as 10 nl. We also demonstrate the platform's capability to generate and detect octanol–water microdroplets. The method reported here offers a fast prototyping method suitable for various microfluidic sensing applications. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the biomechanical characteristics of grafts from three different anterior cruciate ligament (ACL) reconstructive surgeries and to determine which method is better at restoring knee joint stability. Methods: A 31-year-old female volunteer was enrolled in the study. According to the magnetic resonance imaging of her left knee, a three-dimensional model consisting of the distal femur, proximal tibia and fibula, ACL, posterior cruciate ligament, medial collateral ligament and lateral collateral ligament was established. Then, the ACL was removed from the original model to simulate the knee joint after ACL rupture. Based on the knee joint model without the ACL, single-bundle ACL reconstruction, double-bundle ACL reconstruction, and flat-tunnel ACL reconstruction were performed. The cross-sectional diameters of the grafts were equally set as 6 mm in the three groups. The bone tissues had a Young's modulus of 17 GPa and a Poisson's ratio of 0.36. The ligaments and grafts had a Young's modulus of 390 MPa and a Poisson's ratio of 0.4. Six probes were placed in an ACL or a graft to obtain the values of the equivalent stress, maximum principal stress, and maximum shear stress. After pulling the proximal tibia with a forward force of 134 N, the distance that the tibia moved and the stress distribution in the ACL or the graft, reflected by 30 mechanical values, were measured. Results: The anterior tibial translation values were similar among the three groups, with the double-bundle ACL reconstruction group performing the best, followed closely by the patellar tendon ACL reconstruction group. In terms of stress distribution, 13 out of 30 mechanical values indicated that the grafts reconstructed by flat bone tunnels had better performance than the grafts in the other groups, while 12 out of 30 showed comparable outcomes, and 5 out of 30 had worse outcomes. Conclusion: Compared with traditional single-bundle and double-bundle ACL reconstructions, flat-tunnel ACL reconstruction has advantages in terms of stress dispersion. Additionally, flat-tunnel ACL reconstruction falls between traditional double-bundle and single-bundle ACL reconstructions in terms of restoring knee joint stability and is superior to single-bundle ACL reconstruction. [ABSTRACT FROM AUTHOR]

Background: Nonfusion technologies, such as motion-preservation devices, have begun a new era of treatment options in spine surgery. Motion-preservation approaches mainly include total disc replacement for anterior cervical discectomy and fusion. However, for multisegment fusion, such as anterior cervical corpectomy and fusion, the options are more limited. Therefore, we designed a novel 3D-printed motion-preservation artificial cervical corpectomy construct (ACCC) for multisegment fusion. The aim of this study was to explore the feasibility of ACCC in a goat model. Methods: Goats were treated with anterior C3 corpectomy and ACCC implantation and randomly divided into two groups evaluated at 3 or 6 months. Radiography, 3D CT reconstruction and MRI evaluations were performed. Biocompatibility was evaluated using micro-CT and histology. Results: Postoperatively, all goats were in good condition, with free neck movement. Implant positioning was optimal. The relationship between facet joints was stable. The range of motion of the C2-C4 segments during flexion–extension at 3 and 6 months postoperatively was 7.8° and 7.3°, respectively. The implants were wrapped by new bone tissue, which had grown into the porous structure. Cartilage tissue, ossification centres, new blood vessels, and bone mineralization were observed at the porous metal vertebrae-bone interface and in the metal pores. Conclusions: The ACCC provided stabilization while preserving the motion of the functional spinal unit and promoting bone regeneration and vascularization. In this study, the ACCC was used for anterior cervical corpectomy and fusion (ACCF) in a goat model. We hope that this study will propel further research of motion-preservation devices. [ABSTRACT FROM AUTHOR]

Background: Medical professionals are constantly exposed to bodily fluids and sanitizing agents during routine medical procedures. Unbeknownst to many healthcare workers, however, the barrier integrity of medical gloves can be altered when exposed to these substances, potentially resulting in exposure to dangerous pathogens. Methods: This experimental study was designed to test the hypothesis that the durability of both natural and synthetic solvent-exposed medical gloves will be lower than the durability of the gloves in air. The testing consisted of a sample of commercially available medical gloves exposed to 70% ethanol, phosphate buffered saline, and deionized water, aimed at simulating the environments in which medical gloves are commonly worn. Gloves were included in this study based on their performance in previous durability studies in air. Data were collected over a period of three months. The glove assessment device automatically detects pinhole-sized perforations in medical gloves, eliminating the need to visually inspect each glove. Relative durability was measured as the average number of sandpaper touches until glove puncture. Results: Four out of five glove brands performed better when exposed to all three solvents than in air, which is likely due to slippage in the interface between the wet glove and the sandpaper. Sensicare Micro, a polyisoprene surgical glove, had the most consistent durability in all three solvents tested. A two-way ANOVA revealed that both glove brand (P = 0.0001), solvent (P = 0.0001), and their interaction (P = 0.0040, α = 0.05) significantly affected average glove durability. Conclusions: Glove durability did not remain consistent in 70% ethanol, phosphate buffered saline, deionized water, and air. These results make it clear that additional testing and labeling information would help healthcare workers select gloves for use in specific environments to ensure the best barrier protection against disease or toxins. [ABSTRACT FROM AUTHOR]

Hydrogen, as a clean, safe, and efficient energy carrier, is one of the hot energy sources that have attracted much attention. Mo2C, due to the introduction of C atoms, makes the atomic spacing of the Mo lattice decrease and changes the width of the d-band, which makes the electronic properties of Mo2C similar to that of Pt noble metals, exhibiting excellent electrochemical hydrogen precipitation performance. MoS2, due to its special crystal structure and tunable electronic structure, has been widely studied. In this paper, Mo2C nanoparticles were prepared by high-temperature carbonization, and then two-dimensional layered MoS2 were be loaded on Mo2C nanoparticles by the hydrothermal method to synthesize Mo2C/MoS2 composite catalysts. Their electrochemical hydrogen precipitation (HER) performance under acidic conditions was tested. The above catalysts were also characterized by modern material testing methods such as XRD, SEM, TEM, and XPS. The results showed that the composite catalysts exhibited the most excellent electrochemical hydrogen precipitation performance at Mo2C/MoS2-3, with the lowest overpotential at a current density of 10 mA cm−2, Tafel slope, and electrochemical impedance. At the same time, the electrochemically active area was dramatically enhanced, with good stability under prolonged testing. The catalytic activity was significantly improved compared with that of Mo2C and MoS2. The characterization and experimental results indicate that the heterogeneous structure of Mo2C and MoS2 formed a built-in electric field between the two, which accelerated the electron transfer efficiency and provided more active sites. The Mo2C/MoS2 composite catalyst is a low-cost, easy-to-prepare, and high-efficiency electrochemical hydrogen precipitation catalyst, providing a new idea for developing green and clean energy. [ABSTRACT FROM AUTHOR]

Geopolymers are binder materials that are produced by a chemical reaction between silica or aluminum compounds with an alkaline activating solution. Foamed geopolymer materials are increasingly being cited as a viable alternative to popular organic insulation materials. Since the foaming process of geopolymers is difficult to control, and any achievements in improving the performance of such materials are extremely beneficial, this paper presents the effect of the addition of basalt powder on the properties of foamed geopolymers. This paper presents the results of physicochemical studies of fly ash and basalt, as well as mechanical properties, thermal properties, and structure analysis of the finished foams. The scope of the tests included density tests, compressive strength tests, tests of the thermal conductivity coefficient using a plating apparatus, as well as microstructure tests through observations using light and scanning microscopy. Ground basalt was introduced in amounts ranging from 0 to 20% by mass. It was observed that the addition of basalt powder contributes to a reduction in and spheroidization of pores, which directly affect the density and pore morphology of the materials tested. The highest density of 357.3 kg/m3 was characterized by samples with a 5 wt.% basalt powder addition. Their density was 14% higher than the reference sample without basalt powder addition. Samples with 20 wt.% basalt addition had the lowest density, and the density averaged 307.4 kg/m3. Additionally, for the sample containing 5 wt.% basalt powder, the compressive strength exceeded 1.4 MPa, and the thermal conductivity coefficient was 0.1108 W/m × K. The effect of basalt powder in geopolymer foams can vary depending on many factors, such as its chemical composition, grain size, content, and physical properties. The addition of basalt above 10% causes a decrease in the significant properties of the geopolymer. [ABSTRACT FROM AUTHOR]

We developed and analyzed a novel non-sparking material based on CuAlBe for applications in potentially explosive environments. Using a master alloy of CuBe, an established material for anti-sparking tools used in oil fields, mines, or areas with potentially explosive gas accumulations, and pure Al, we used an Ar atmosphere induction furnace to obtain an alloy with ~10 wt% Al and ~2 wt% Be percentages and good chemical and structural homogeneity. The new material was tested in an explosive gaseous mixture (10% H2 or 6.5% CH4) under extremely strong wear for 16,000 cycles, and no hot sparks capable of igniting the environment were produced. The material was used in the form of hot-rolled plates obtained from melted ingots. The experimental results reflect the use of a suitable material for non-sparking tools. This material has good deformability during hot rolling, abnormal grain growth during deformation under heat treatment and special thermo-mechanical processing, and no high chemical composition variation. Additionally, there are slightly different corrosion resistance and mechanical properties between the melt and hot-rolled state of CuAlBe material. Through hot rolling, the material's corrosion resistance increased, reducing the chances of generating sparks capable of causing explosions. [ABSTRACT FROM AUTHOR]

Payloads for light unmanned free balloons must meet several safety requirements such as being able to protect the inner electronics in order to extract scientific data and to reduce the chance of inflicting personal injury in case of an accidental fall. This article proposes a novel payload structure, which exhibits the form of a dodecahedron. The actual form was determined by carrying out theoretical drop tests on different polyhedrons using the finite element method (FEM). From the simulations, it could be deduced that the dodecahedron was the optimal choice, since the duration of the impact was longer, while the impact force was slightly lower. The payload was produced by additive technologies; therefore, after performing tensile tests on probable materials, PLA was selected as the optimal candidate. The theoretical results about the dodecahedron's ability were validated by laboratory and real-life drop tests, where the new payload was subjected to 56% less impact force under a 78% longer collision time compared to a classic, rectangular cuboid design. Based on these tests, it was demonstrated that the new structure is safer and it is applicable. [ABSTRACT FROM AUTHOR]

Protonic ceramic electrolysis cells (PCECs) are high-temperature electrolysers (HTEs) which use ceramic electrolytes characterized by high protonic conductivity. Compared with other HTEs (e.g., solid oxide electrolysis cells, SOECs), PCEC devices work at considerably lower temperatures (i.e., 350-600 °C compared with 700-900 °C of SOEC). Nowadays, studies related to PCEC have been confined to the lab scale, with only a few attempts to scale up this technology. A single repeating unit (SRU) or a stack of large area PCEC cells is still a technological challenge and the formulation of appropriate sealants to join ceramic cells and metallic interconnects is necessary to fulfil this task. In this study, three compositions of Si-based glass-ceramic (two Na-rich and one Ba-rich) have been chemically and thermomechanically tested with materials for PCEC electrolyte (Ba(Ce,Zr) 1-y M y O 3-δ) and a ferritic stainless steel interconnect (FSS, AISI441). Afterwards, the joined sample were characterized using SEM-EDX and XRD. One of the studied compositions, a Si-based glass-ceramic containing also Na and Zr, showed promising results. The results of the microstructural analyses highlighted excellent compatibility with both the BCZY72 electrolyte and the AISI441 stainless steel after joining and ageing of 1000 h at 600 °C in static air. Moreover, this glass-ceramic system has been joined with AISI441 steel and characterized at 600 °C with the application of a voltage and different atmospheres. Good compatibility of the glass-ceramic with the AISI441 was highlighted by the microstructural characterization also in these conditions. • Glass/ceramic sealants for joining PCEC cells. • Thermochemical compatibility with SoA materials for PCEC and AISI441. • Microstructural characterization of the joined samples. • Deposition via robocasting of the sealant and characterization in static air. [ABSTRACT FROM AUTHOR]

In this paper, a novel methodology is presented to evaluate the true nonlinear shear response of continuous fiber-reinforced plastic (CFRP) unidirectional laminae. It requires simple off-axis tensile experiments to be conducted and a finite element (FE) representation of them with a material constitutive law capable of handling nonlinearity in shear. Upon successful evaluation of the normal stiffness properties, the shear stress-strain response is derived via numerical calibration of the underlying FE models. The presented approach is also demonstrated by processing the raw data of an extensive material characterization test campaign conducted on a thermoplastic matrix CFRP. The outcome is compared to the conventional methods for shear response derivation using relevant standards such as ASTM D3518 and ASTM D5379. It has been successfully demonstrated that the pseudo-hardening phenomenon obtained from standard shear experiments as a result of fibers aligning with load direction can be eliminated with off-axis specimen tension experiments, thus, the true shear stress versus deformation response can be extracted up to failure. The main purpose of current work is to demonstrate the inconsistency in the available standard methods related to mechanical testing-based derivation of nonlinear in-plane shear behavior of UD plies. In addition, a novel technique is presented to achieve a more accurate prediction of nonlinear shear stress and strain along the entire representative loading range that contributes to more accurate simulations of composite parts up to failure and thus, better strength predictions. [ABSTRACT FROM AUTHOR]

Silica sol can activate the surface of hollow ceramic microspheres and improve the properties of composite materials by improving the interface between the microspheres and the epoxy resin. The group changes on the surface of microspheres were measured using infrared spectroscopy. The microspheres were observed with a scanning electron microscope. The density, water absorption, and mechanical properties of the materials were tested using scales and mechanical testing machines. The results showed that SiO2 and silane molecules were introduced on the surface of the microspheres after treatments. As the silica sol content increased, the slurry viscosity increased by 34.5%, the composite density increased by 5.8%, and the water absorption decreased by 35.8%. When the silica sol content was 25%, the flexural strength and compressive strength of the composites were 73.49 and 116.27 MPa, respectively, which were 37.8% and 23.6% higher than those of the untreated composites, and the mechanical properties became clearly improved. High mechanical properties enable the materials to be used in deeper ocean areas. Highlights: Nanoparticles are introduced onto the surface of hollow microspheres.The activated microspheres can bind better to the silane coupling agent.Silane coupling agent assisted by silica sol improved interfacial bonding.Surface activation of microspheres improves the properties of composites. [ABSTRACT FROM AUTHOR]

The article presents a new method for synthesizing porous metal- and metalloid-based nanomaterials using the NaK alloy as a versatile reagent. This approach eliminates the need for additional reagents and allows for the production of functional materials with controllable porous structures. The materials have potential applications in catalysis, energy storage, and green chemistry. The study also demonstrates the use of the materials in Na- and K-ion batteries, achieving good cycling stabilities and capacities. The proposed synthetic approach is scalable and versatile, making it suitable for various applications. [Extracted from the article]

BACKGROUND: In order to explore the effect of ozone sterilization treatment on tomato disease control and increase fruit setting rate, this study took 906 pink fruit tomato as test material, used a small ozone generator to carry out ozone treatment single‐factor test, and then selected orthogonal table to guide the ozone treatment combination. The effects of different ozone treatment concentration, ozone treatment duration and ozone treatment times on the growth, disease and fruit setting rate of potted tomato were analyzed. RESULTS: Different ozone treatment had effects on leaf mildew, gray mold and fruit setting rate of tomato. The influence degree of three factors on leaf mildew, gray mold and fruit setting rate was from large to small, a > b > c, a > c > b, b > a > c. A quadratic regression model was established with the control effect of tomato leaf mildew, gray mold and fruit setting rate as response values, and the optimal parameter combination was determined: The ozone treatment concentration was 0.0465 g kg−1, the ozone treatment time was 30 min, and the ozone treatment times were twice a week. In this case, the control efficiency of tomato leaf mildew was 95.02%, the control effect of gray mold was 99.49%, and the fruit setting rate was 76.5%. The test parameters were accurate and reliable. CONCLUSION: The ozone sterilization method proposed in this article is safe and green, and can provide theoretical support for the recovery and reconstruction of tomato disease in a glasshouse. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This paper examines the consolidation and settlement behaviour of soft clay deposits treated with granular columns (single and in groups). Two Rowe cell loading chambers were used to conduct the investigations on samples of kaolin and a local Belfast natural estuarine alluvium called 'sleech'. Tests were carried out on unreinforced samples and then reinforced samples with single and multiple column configurations. The test duration for each test was between 3 and 4 months, depending on the test material and the granular column configuration. The settlement reduction factors based on primary and secondary consolidation were examined. The study suggests that the effectiveness of granular columns at mitigating primary and/or secondary settlement is directly related to the loading intensity, the stress history and the creep characteristics of the subsoil. It was also found that the stress concentration ratio reduced with the stress level. Secondary consolidation also has some effects on the stress concentration ratio. [ABSTRACT FROM AUTHOR]

The knowledge of the mechanical behavior of a 3D-printed material is fundamental for the 3D printing outbreaking technology to be considered for a range of applications. In this framework, the significance, reliability, and accuracy of the information obtained by testing material coupons assumes a pivotal role. The present work focuses on an evaluation of the static mechanical properties and failure modes of a 3D-printed short carbon fiber-reinforced polyamide in relation to the specimen's unique meso-structural morphology and water content. Within the manufacturing limitations of a commercially available printer, specimens of dedicated combinations of geometry and printing patterns were specifically conceived and tested. The specimens' meso-structure morphologies were investigated by micro-computed tomography. The material failure mechanisms were inferred from an analysis of the specimens' fracture surfaces and failure morphologies. The outcomes of the present analysis indicate that each test specimen retained proper mechanical properties, thereby suggesting that they should be accurately designed to deliver representative information of the underlying material beads or of their deposition layout. Suggestions on the adoption of preferred test specimens for evaluating specific material properties were proposed. [ABSTRACT FROM AUTHOR]

Materials used in nuclear power plants are exposed to cyclic loading, which is why the understanding of fatigue behaviour is of great importance. Because of high time investments and resulting increased costs, Lifetime Prediction Methods, which significantly reduce the amount of specimen, have already been developed. Within this paper, the Lifetime Prediction Method MiDAcLifeincr is presented, which enables a determination of a trend S‐N curve in the High‐Cycle‐Fatigue‐regime based on only one fatigue test and the combination of conventional fatigue testing with NDT‐related measurement techniques. The process‐orientated monitoring of the cyclic deformation behaviour provides the basis for the time‐ and cost‐effective provision of fatigue data. Compared with previous methods, the consideration of variable loading is an essential aspect of the research application. The test material is a 20MnMoNi5‐5 steel, the results of which are extended to include other steels for validation reasons. Highlights: The new method enables a fatigue life calculation on the basis of only one fatigue test.A correlation between the material reaction and the introduced damage could be found.The applicability of the method is independently of the applied measurement technique. [ABSTRACT FROM AUTHOR]

The capability to produce suture material using three‐dimensional (3D) printing technology may have applications in remote health facilities where rapid restocking of supplies is not an option. This is a feasibility study evaluating the usability of 3D‐printed sutures in the repair of a laceration wound when compared with standard suture material. The 3D‐printed suture material was manufactured using a fused deposition modelling 3D printer and nylon 3D printing filament. Study participants were tasked with performing laceration repairs on the pigs' feet, first with 3‐0 WeGo nylon suture material, followed by the 3D‐printed nylon suture material. Twenty‐six participants were enrolled in the study. Survey data demonstrated statistical significance with how well the 3D suture material performed with knot tying, 8.9 versus 7.5 (p = 0.0018). Statistical significance was observed in the 3D‐printed suture's ultimate tensile strength when compared to the 3‐0 Novafil suture (274.8 vs. 199.8 MPa, p = 0.0096). The 3D‐printed suture also demonstrated statistical significance in ultimate extension when compared to commercial 3‐0 WeGo nylon suture (49% vs. 37%, p = 0.0215). This study was successful in using 3D printing technology to manufacture suture material and provided insight into its usability when compared to standard suture material. [ABSTRACT FROM AUTHOR]

A wide variety of biomaterials has been developed to assist in wound healing, including acellular animal and human‐derived protein matrices. However, millions of patients worldwide still suffer from non‐healing chronic wounds, demonstrating a need for further innovation in wound care. To address this need, a novel biomaterial, the human keratin matrix (HKM), was developed, characterised, and tested in vitro and in vivo. HKM was found to be degradation‐resistant, and a proteomics analysis showed it to be greater than 99% human keratin proteins. PCR revealed adult human epidermal keratinocytes (HEKa) grown in contact with HKM showed increased gene expression of keratinocyte activations markers such as Epidermal Growth Factor (EGF). Additionally, a cytokine microarray demonstrated culture on HKM increased the release of cytokines involved in wound inflammatory modulation by both HEKa cells and adult human dermal fibroblasts (HDFa). Finally, in a murine chronic wound model, full‐thickness wounds treated weekly with HKM were smaller through the healing process than those treated with human amniotic membrane (AM), bovine dermis (BD), or porcine decellularized small intestinal submucosa (SIS). HKM‐treated wounds also closed significantly faster than AM‐ and SIS‐treated wounds. These data suggest that HKM is an effective novel treatment for chronic wounds. [ABSTRACT FROM AUTHOR]

Purpose: This study explores how titanium oxide (TiO2) filler influences the specific wear rate (SWR) in flax fiber-reinforced epoxy composites (FFRCs) through a Taguchi approach. It aims to boost abrasive wear resistance by incorporating TiO2 filler, promoting sustainable and eco-friendly materials. Design/methodology/approach: This study fabricates epoxy/flax composites with TiO2 particles (0–8 wt%) using hand layup. Composites were tested for wear following American Society for Testing and Materials (ASTM) G99-05. Statistical analysis used Taguchi design of experiments (DOE), with ANOVA identifying key factors affecting SWR in abrasive sliding conditions. Findings: The study illuminates how integrating TiO2 filler particles into epoxy/flax composites enhances abrasive wear properties. Statistical analysis of SWR highlights abrasive grit size (grit) as the most influential factor, followed by normal load, wt% of TiO2 and sliding distance. Grit size has the highest effect at 43.78%, and wt% TiO2 filler contributes 15.61% to SWR according to ANOVA. Notably, the Taguchi predictive model closely aligns with experimental results, validating its reliability. Originality/value: This paper integrates TiO2 filler and flax fibers to form a novel hybrid composite with enhanced tribological properties in epoxy composites. The use of Taguchi DOE and ANOVA offers valuable insights for optimizing control variables, particularly in natural fiber-reinforced composites (NFRCs). [ABSTRACT FROM AUTHOR]

An expanded description of particle morphology and the analysis of its relationships with physical properties may help to optimize the selection of raw materials and particle size fractions used as growing media constituents. Previous works have described the outlines of these relations based mostly on sieving procedures to characterize particle size distribution. They have shown limited and sometimes contradictory results due to the different methods used, size fractions selected, and physical properties measured. Also, sieve analysis, which separates particles based on their width, is less accurate for non‐spherical particles, which is the case for most growing media constituents. Recent works have promoted the use of dynamic image analysis (DIA) to precisely analyze both particle length and width. Five raw materials were chosen (white and black peats, coir, pine bark, and wood fiber) and sieved to obtain various particle size fractions. For each particle size fraction and the raw materials, the mean weight diameter (MWD), derived from sieving, was calculated, whereas mean particle length and width were determined using a DIA tool, the QicPic device. Also, physical properties were assessed from water retention curves established using Hyprop systems. The statement that the larger the particle size, the higher the air‐filled porosity (AFP), the lower the water holding capacity (WHC) was more precisely redefined. Large variations in WHC and AFP mainly occurred for finest particle size fractions, whereas changes were conversely very small or non‐existent for larger particle sizes. From data obtained for each particle size fractions, regression models were established to relate mean particle length and width (both determined using DIA) and MWD (determined from sieving) with WHC and AFP. Mean particle length was identified as the most relevant parameter for predicting WHC and AFP of the raw materials tested. Core Ideas: Image analysis can be used to characterize particle size to understand relationships with physical properties.Changes in physical properties as a function of particle size occur within a limited size range.Particle length provides the best estimate of raw material properties based on those of individual fractions. [ABSTRACT FROM AUTHOR]

This paper reports on a numerical study focused on the characterization of the masonry and infill material behaviour of stone arch railway bridges. The study is based on experimental data from testing campaigns carried out in materials of two granite stone bridges. The campaigns comprise lab tests on stone masonry samples (blocks and joints) collected from the bridge structure, as well as in-situ flat-jack testing and Ménard pressuremeter tests on masonry and infill components, respectively. A strategy was developed resorting to Finite Element (FE) methodologies involving local scale numerical simulation of the joint lab tests (shear tests) and both in-situ tests (Flat-jack and Ménard pressuremeter tests), aiming at the calibration and validation of the material parameters to be used in global scale numerical simulations of the bridges' structural behaviour. The joint shear behaviour is simulated using a FE discrete formulation based on contact elements whereas the Flat-jack and Ménard pressuremeter testing is simulated using FE continuous homogeneous nonlinear materials based on a Drucker-Prager (D-P) model. The calibration of the D-P model input parameters is performed through a sensitivity analysis followed by an optimization strategy based on a genetic algorithm. The methodology showed the potential to calibrate the material constitutive parameters to be adopted in FE numerical models of this type of bridge. [ABSTRACT FROM AUTHOR]

The article outlines Insight's current awareness service, which covers a wide range of British and international publications, conference proceedings, and multimedia products related to non-destructive testing (NDT). It categorizes the literature search into 14 sections, providing resources for various NDT techniques, and invites comments and contributions for further enhancement, while also offering information on accessing papers.