Young's Modulus Values Research Articles

Porosity dependence of sound velocities in partially sintered alumina, zirconia, ATZ, and mullite ceramics

AbstractYoung's modulus and sound velocities of partially sintered alumina, zirconia, ATZ, and mullite ceramics with a broad range of porosities determined via the impulse excitation technique (IET) and the ultrasonic wave propagation pulse‐echo technique (UPT) are found to be in good agreement and exhibit sigmoidal curves as a function of the sintering temperature. The porosity dependence of the relative values of Young's modulus and sound velocities is either close to or below (but never above) the prediction based on an exponential relation, and none of them is significantly below the prediction based on a percolation relation or a recently proposed numerical benchmark relation for overlapping monosized spheres. Values are lower when concave pores or irregular anisometric grains are dominating. The correlation of the normalized longitudinal wave velocities and relative transverse wave velocities, with VL/VT ratios ranging from 0.50 to 1.91, is well predicted by models for Poisson's ratios between 0.35 and 0.2.

Anisotropy, Anatomical Region, and Additional Variables Influence Young's Modulus of Bone: A Systematic Review and Meta-Analysis.

The importance of finite element analysis (FEA) is growing in orthopedic research, especially in implant design. However, Young's modulus (E) values, one of the most fundamental parameters, can range across a wide scale. Therefore, our study aimed to identify factors influencing E values in human bone specimens. We report our systematic review and meta-analysis based on the recommendation of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guideline. We conducted the analysis on November 21, 2021. We included studies investigating healthy human bone specimens and reported on E values regarding demographic data, specimen characteristics, and measurement specifics. In addition, we included study types reporting individual specimen measurements. From the acquired data, we created a cohort in which we performed an exploratory data analysis that included the explanatory variables selected by random forest and regression trees methods, and the comparison of groups using independent samples Welch's t test. A total of 756 entries were included from 48 articles. Eleven different bones of the human body were included in these articles. The range of E values is between 0.008 and 33.7 GPa. The E values were most heavily influenced by the cortical or cancellous type of bone tested. Measuring method (compression, tension, bending, and nanoindentation), the anatomical region within a bone, the position of the bone within the skeleton, and the bone specimen size had a decreasing impact on the E values. Bone anisotropy, specimen condition, patient age, and sex were selected as important variables considering the value of E. On the basis of our results, E values of a bone change with bone characteristics, measurement techniques, and demographic variables. Therefore, the evaluation of FEA should be performed after the standardization of in vitro measurement protocol. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Effect of thermal, mechanical and photophysical properties of high emissive photoluminescence organic pigments

This research aims to synthesize highly visible, bright emission fluorescent dye molecules in daylight to produce PU films and PU resource safety materials. Here we have developed four different types of highly visible PU films in which a cyano-substituted methoxyphenylene core with an additional electron-withdrawing and-donating unit is used to produce a bright orange color with twisted rigid conformational dyes. Modifications in the mechanical behavior and thermal stability properties of PU films were tested by tensile tests, TGA and DSC. The samples of PU film exhibit exceptional elasticity, with a high elongation breaking point and good young's modulus value. Furthermore, these synthesized dyes were measured for photophysical properties and other parameters such as solvent effect, quantum yield and lifetime. The quantum yields of highly visible dyes were measured in both solution and solid phase and found to be in the range of 0.25–0.48 and 0.15 to 0.55, respectively. The HOMO-LUMO energy gap of the dyes in the solid state is significantly lower than that in the solution state. This related to the dyes which exhibiting a lifetime in THF solution of about 1.96–2.41 ns, whereas in the solid state, the lifetime is much better about 6.43–19.61 ns. This indicating that the dyes in the solid state are energetically easier and hence the solid state of dyes shows higher lifetime.

Multi-analytical investigation of the physical, chemical, morphological, tensile, and structural properties of Indian mulberry (Morinda tinctoria) bark fibers

In this study, micro-cellulosic fibers were isolated from the bark of Morinda tinctoria (MT) and characterized for the first time. The anatomical, physical, chemical, thermal, and mechanical properties of the M. tinctoria bark fiber (MTBF) were investigated. The mean diameter and density values were determined to be 32.013 ± 1.43 μm and 1.4875 g/cm³, respectively. Zeta potential analysis and particle size measurements provided the evidence of enhanced micro-particle behavior on the fiber's surface. Various structural characterizations confirmed the presence of polysaccharide structures, monosaccharide compositions, glycosidic residues (sugar linkages), and cohesive reactions of TMSA (Trimethylsilyl alditol) derivatives, indicating the fiber's potential for strong surface absorption properties. X-ray diffraction analysis revealed a crystallinity index of 51 % and a crystallite size of 3.086 nm for MTBF. Fourier transform infrared analysis indicated the presence of cellulose, hemicellulose, and lignin constituents, along with their corresponding functional groups. The calculated values of Young's modulus and tensile strength were determined to be 75.7 GPa and 746.77 MPa, respectively. Thermogravimetric analysis demonstrated the thermal stability of the extracted MTBF up to 240 °C. Based on these findings, the MT microfibrils derived from the bark can be considered as potential substitutes for existing synthetic composites, offering reinforcement for novel bio composites.

Effect of carbonaceous reinforcements on mechanical properties of ZrB2-SiC composites via nanoindentation study

In the present work, silicon carbide (SiC) reinforced zirconium diboride (ZrB2) ceramic was studied. ZrB2 reinforced with 20 vol% SiC (ZS) and with additives multi-walled carbon nanotubes (MWCNTs), graphene nanoplatelets (GNPs), and CNT + GNP were consolidated via spark plasma sintering. ZS with carbon additives (CNT + GNP) composite (ZSCG) showed the highest densification (98.2 %) than that of ZS sample (91 %) via Archimedes' method. Crystallite size calculated via XRD showed a value of (56 ± 1) for ZS and the lowest crystallite size value (47 ± 1) for ZSCG, attributed to the pinning effect of carbonaceous reinforcements (CNT + GNP) at the grain boundaries, which restrict the grain growth in the composite. Nanohardness for the composite samples ranges from ~24 to 33 GPa. ZSCG composite showed the highest nanohardness of 33 GPa attributed to the bridging of long and flexible CNTs adjacent to GNPs to form 3-D hybrid structures restricting their agglomeration, which resulted in a high interfacial area between the matrix and the hybrid reinforcement leading to better load transfer. The theoretically calculated Young's modulus from various models (rule of mixture, Voigt Reuss, and Halpin Tsai (HT)) was compared with the experimental Young's modulus. The calculated Young's modulus value via the HT model (370–411 GPa) is in close agreement with the experimental values (364–401 GPa) owing to consideration of porosity and the interfacial debonding factor. Also, the lowest debonding factor was determined for the ZSCG composite (0.47) in comparison with the ZSC composite (0.86) suggesting increased bonding strength which results in the enhancement of mechanical properties. So, it was finally concluded that the finer crystallite size, improved hardness, less debonding factor, and better load transfer mechanism can make ZSCG composite a viable candidate for high-temperature applications.

Sustainable biomass-based composite biofilm: Sodium alginate, TEMPO-oxidized chitin nanocrystals, and MXene nanosheets for fire-resistant materials and next-generation sensors

Efficient utilization of natural biomass for the development of fireproof materials and next-generation sensors faces various challenges in the field of fire safety and prevention. In this study, renewable sodium alginate (SA), TEMPO-oxidized chitin nanocrystals (TOChNs), and MXene nanosheets were employed to fabricate a sustainable, flexible, and flame-retardant composite biofilm, donated as STM, utilizing a simple and environmentally friendly evaporation-induced self-assembly technique. The incorporation of SA, TOChNs, and MXene in a weight ratio of 50/10/40 led to improved mechanical properties of the resulting STM-40 films, as evidenced by increased tensile strength and Young's modulus values of approximately 36 MPa and 4 GPa, respectively. Notably, these values were approximately 3 and 11 times higher than those observed for the pure SA film. Moreover, the STM-40 films demonstrated highly sensitive fire alarm capabilities, exhibiting a superior flame alarm response time of 0.6 s and a continuous alarm time of approximately 492 s when exposed to flames. The STM exhibited exceptional flame retardancy due to the synergistic carbonization between MXene and SA/TOChNs, resulting in a limiting oxygen index of 45.0 %. Furthermore, its maximum heat release rate decreased by over 90.1 % during the test. This study presents a novel approach for designing and developing fire-retardant fire alarm sensors by utilizing natural biomass.

Resonance of the tympanoperiotic complex of fin whales with implications for their low frequency hearing.

The tympanoperiotic complex (TPC) bones of the fin whale skull were studied using experimental measurements and simulation modeling to provide insight into the low frequency hearing of these animals. The study focused on measuring the sounds emitted by the left and right TPC bones when the bones were tapped at designated locations. Radiated sound was recorded by eight microphones arranged around the tympanic bulla. A finite element model was also created to simulate the natural mode vibrations of the TPC and ossicular chain, using a 3D mesh generated from a CT scan. The simulations produced mode shapes and frequencies for various Young's modulus and density values. The recorded sound amplitudes were compared with the normal component of the simulated displacement and it was found that the modes identified in the experiment most closely resembled those found with Young's modulus for stiff and flexible bone set to 25 and 5 GPa, respectively. The first twelve modes of vibration of the TPC had resonance frequencies between 100Hz and 6kHz. Many vibrational modes focused energy at the sigmoidal process, and therefore the ossicular chain. The resonance frequencies of the left and right TPC were offset, suggesting a mechanism for the animals to have improved hearing at a range of frequencies as well as a mechanism for directionality in their perception of sounds.

Microstructure analysis of a CoCrFeNi high-entropy alloy after compressive deformation

A sharp increase in the dislocation density and in the fraction of low-angle grain boundaries (LAGBs) has often been observed during the early-stage deformation of high-entropy alloys. To study the underlying reasons for this behavior, the microstructure of plastic deformation applying at a low compressive strain of 3.3% was analyzed in the CoCrFeNi high-entropy alloy. This deformation results in a relatively higher dislocation density in the CoCrFeNi alloy in comparison to that in pure Nickel. A significantly increased dislocation density was observed near grain boundaries that is collaborated by a low value of the anisotropy factor (Az ∼ 2.37) in CoCrFeNi alloys offering favorable conditions for dislocation generation. Moreover, the low anisotropy factor in CoCrFeNi alloys appears to be caused by their strong chemical heterogeneity. The relatively easy dislocation generation provides an important feature of dislocation interactions in the CoCrFeNi alloy. Local high hardness and high Young's modulus values were observed at newly-formed LAGBs. The evolution of LAGBs strongly depends on the grain orientation and the internal strain, and LAGBs are gradually formed by the accumulation and self-organization into LAGBs at a surprisingly low strain of about 2.61%. The formation of these boundaries is intrinsically promoted by the low stacking fault energy of the CoCrFeNi alloy. An easy dislocation generation and a low strain of LAGB formation result in a high density of retained dislocations, giving rise to the observed mechanical performance of the material.

Combination of ultra-micro angiography and sound touch elastography for diagnosis of primary Sjögren's syndrome: a diagnostic test.

Primary Sjogren's syndrome (PSS) is a prevalent systemic autoimmune disease. However, the current gold standard diagnostic method is invasive, increasing the difficulty of patient acceptance and then delaying treatment. Therefore, a non-invasive, convenient, and effective diagnostic method is required. Although salivary gland ultrasonography (SGUS) is a good choice, previous studies have not found suitable parameters to diagnose PSS. Salivary gland involvement in patients with PSS leads to changes in gland stiffness and vascularization, so we combined sound touch elastography (STE) and ultra-microangiography (UMA) to demonstrate the diagnostic effectiveness of ultrasonography in PSS. This prospective study included 27 patients with PSS and 20 healthy controls, with all participants forming a random series. Major salivary glands were examined with UMA and STE. Color pixel percentage (CPP), shear wave velocity (SWV), and Young's modulus values were investigated, and the combination of these parameters was evaluated by logistic regression analysis. For Young's modulus and SWV in the elasticity index, combined evaluation of both parotid glands and submandibular glands yielded an area under the receiver operating characteristic (ROC) curve (AUC) and confidence interval (CI) of 0.819, 0.699-0.938 and 0.801, 0.677-0.925, respectively. The levels of CPP in the parotid glands were significantly elevated (P<0.003) among patients compared to those in the control group, whereas the CPP values in the submandibular glands were not statistically different (P>0.086). We evaluated the elasticity values of the total 4 glands and the CPP of parotid glands together by logistic regression modeling. The ROC curve yielded an AUC of 0.954 (95% CI: specificity 0.849-0.994) which showed the best accuracy, with 92.6% sensitivity and 85.0% specificity. The use of STE and UMA to examine the salivary glands may aid in the diagnosis of PSS, and their combination may be a promising method. This is good news for patients with PSS who are not suitable or unwilling to undergo labial gland biopsy.

Assessing vaginal wall indexes in premenopausal versus postmenopausal women by transrectal linear array high-frequency probe

ObjectiveThis study aimed to verify the feasibility of 2D measurement of full-layer thickness of vaginal wall and evaluation of its elasticity by shear wave elastic imaging using transrectal linear array high-frequency ultrasound and to investigate the differences of vaginal wall indexes in premenopausal versus postmenopausal women.MethodFrom September to November 2022, a total of 87 women in the Department of Gynecology, Nanjing First Hospital were examined by a sonographer using transrectal linear array high-frequency ultrasound, including 34 women of reproductive age and 53 postmenopausal women. The vagina was divided into upper, middle, and lower segments, and the full-layer thickness of each part was measured. Then shear wave elastography (SWE) was used, and the average value of Young's modulus was used to evaluate the degree of vaginal elasticity.ResultsTransrectal linear array high-frequency ultrasound can clearly display structures of vaginal wall; measurement of the full thickness of the vaginal wall and evaluation of the degree of vaginal elasticity were feasible. There was a statistically significant difference in the thickness of each part of the vaginal wall between pre- and postmenopausal women (P < 0.001); there was no significant difference in the vaginal Young's modulus of pre- and postmenopausal women (P = 0.073). ConclusionTransrectal linear array high-frequency ultrasonography is a non-invasive and feasible method to measure vaginal wall thickness (VWT) and elasticity. There are significant differences in VWT between pre- and postmenopausal women.

Prediction of Mechanical Behavior of Epoxy Polymer Using Artificial Neural Networks (ANN) And response Surface Methodology (RSM)

The aim of this study is to analyze the effect of different geometries and sections on the mechanical properties of epoxy specimens. Five tensile tests were carried out on three types of series. The experimental results obtained were 1812.21 MPa, 3.90% and 41.91 MPa for intact specimens, 1450.41 MPa, 2.16% and 21.28 MPa for specimens with hole and 750.77 MPa, 2.77% and 11.89 MPa for specimens with elliptical -notched for Young's modulus, strain and stress respectively. In addition, the experimental results indicated that the mechanical properties of both (Young's modulus value and stress value) were higher in an intact specimen. Afterwards, the nonlinear functional relationship of input parameters between epoxy sample geometries and sections was established using the response surface model (RSM) and the artificial neural network (ANN) to predict the output parameters of mechanical properties (Young's modulus and stress). In addition, the design of experiment was developed by the Analysis of the Application of Variance (ANOVA). The results showed the superiority of the ANN model over the RSM model, where the correlation coefficient values for the model datasets exceed ANN (R2 = 0.984 for Young's modulus and R2 = 0.981 for the constraint).

Noninvasive hemodynamic indices of vascular aging: an in silico assessment.

Vascular aging (VA) involves structural and functional changes in blood vessels that contribute to cardiovascular disease. Several noninvasive pulse wave (PW) indices have been proposed to assess the arterial stiffness component of VA in the clinic and daily life. This study investigated 19 of these indices, identified in recent review articles on VA, by using a database comprising 3,837 virtual healthy subjects aged 25-75 yr, each with unique PW signals simulated under various levels of artificial noise to mimic real measurement errors. For each subject, VA indices were calculated from filtered PW signals and compared with the precise theoretical value of aortic Young's modulus (EAo). In silico PW indices showed age-related changes that align with in vivo population studies. The cardio-ankle vascular index (CAVI) and all pulse wave velocity (PWV) indices showed strong linear correlations with EAo (Pearson's rp > 0.95). Carotid distensibility showed a strong negative nonlinear correlation (Spearman's rs < -0.99). CAVI and distensibility exhibited greater resilience to noise compared with PWV indices. Blood pressure-related indices and photoplethysmography (PPG)-based indices showed weaker correlations with EAo (rp and rs < 0.89, |rp| and |rs| < 0.84, respectively). Overall, blood pressure-related indices were confounded by more cardiovascular properties (heart rate, stroke volume, duration of systole, large artery diameter, and/or peripheral vascular resistance) compared with other studied indices, and PPG-based indices were most affected by noise. In conclusion, carotid-femoral PWV, CAVI and carotid distensibility emerged as the superior clinical VA indicators, with a strong EAo correlation and noise resilience. PPG-based indices showed potential for daily VA monitoring under minimized noise disturbances.NEW & NOTEWORTHY For the first time, 19 noninvasive pulse wave indices for assessing vascular aging were examined together in a single database of nearly 4,000 subjects aged 25-75 yr. The dataset contained precise values of the aortic Young's modulus and other hemodynamic measures for each subject, which enabled us to test each index's ability to measure changes in aortic stiffness while accounting for confounding factors and measurement errors. The study provides freely available tools for analyzing these and additional indices.

Analytical model of mechanical properties for a hierarchical lattice structure based on hierarchical body-centered cubic unit cell

Hierarchical structure features complex geometric topology and excellent mechanical properties. In this work, analytical models are developed to predict the mechanical properties as Young's modulus, Poisson's ratio, and yield stress of a lattice structure composed of hierarchical body-centered cubic. Analytical results were validated by finite element simulations. The compressed experiments of lattice samples fabricated by powder bed fusion were conducted to examine mechanical properties. The analytical model agrees well with the simulation results and experimental results. The largest discrepancy from the analytical model to the finite element simulations for Young's modulus of lattice structures is 7.5%. Regarding Poisson's ratio and yield stress, the largest discrepancy are 0.05% and 13.1%, respectively. Furthermore, the Young's modulus shows an increasing trend as the relative density of lattices increases and geometrical ratio λ decreases. Moreover, the influence of shear deformation on the mechanical properties of the lattice structures decreases with the gradual increase of geometrical ratio λ. The Young's modulus and yield stress for the lattices increase as geometrical ratio λ decreases with increasing relative density. The Poisson's ratio shows an opposite trend to the Young's modulus as well as the yield stress. Finally, the degree of anisotropy of Young's modulus for the lattice structure is investigated. The range of anisotropy values for the lattice structure is large, i.e., 2.98∼745. The anisotropy value of Young's modulus decreases with the relative density increasing. And, the anisotropy value of lattices decreases with increasing relative density, i.e., the monotonic trend. This work provides guidance for future designs of the hierarchical lattice structures from the aspects of theoretical prediction.

Estimation of compressive strength of cement mortars using impulse excitation technique and a genetic algorithm

Compressive strength, a crucial mechanical property of cement mortars, is typically measured destructively. However, there is a need to evaluate the strength of unique cement-based samples at various ages without causing damage. In this paper, a predictive framework using a genetic algorithm (GA) is proposed for estimating the compressive strength of ordinary cement-based mortars based on their dynamic elastic modulus, measured non-destructively using the impulse excitation technique. By combining the Popovics model (PM) and the Lydon–Balendran model (LBM), the static elastic modulus of samples was calculated using constant coefficients, representing an equivalent compressive strength. A GA was then employed to determine optimal values for these coefficients. The results showed that the LBM-based strength was dominant in the middle range of the dynamic Young's modulus while the PM-based strength was dominant for higher and lower values of the dynamic Young's modulus. The model was found to have a small root mean square error (3.1%). The findings suggest that this non-destructive model has potential for predicting the mechanical properties of cement mortars. It allows efficient evaluation of compressive strength without destructive testing, offering advantages for reliable assessments of cement-based materials.

Effect of unit cell shape and structure volume fraction on the mechanical and vibration properties of 3D printed lattice structures

Lattice structures have been proven to be one of the best choices since their inception, for various structural and other commercial applications, for enhanced mechanical properties, especially in the case of vibration isolation, where band gaps play a vital role. In the present study, additively manufactured 3D printed lattices are prepared with the help of fused deposition modelling (FDM) under various design variations such as Diamond, Kelvin, and Octa formations. Further, three variations in the form of cell density have been used in all the designs, such as low, medium, and high density. The effect of the design variations on Young’s modulus, ultimate compressive strength, and plateau stress have been studied, and comparative analysis amongst the designs has been carried out. In the case of the diamond foam, the Young’s modulus of 54.84, 79.43, and 63.13 MPa has been obtained for low, medium, and high density, respectively. However, in the case of Octa formation with a high-density apology, highest value of young modulus is obtained, which is 174.94 MPa. But the plateau stress is the best in the case of high-density diamond topology and least in the case of high-density Octa formation. In addition, the diamond foam with the medium density has shown the best compressive strength, i.e., 5.003 MPa. Moreover, vibration analysis properties were explored; interestingly, it has been seen that the transmissivity of the medium-form structures for all shapes is higher than the others whereas the natural frequency of the Diamond and Octa shapes is lower. Hence the shape and form of the lattice have a significant effect on the final properties of the lattices and lattice structures contribute to structural integrity in terms of better properties and enhanced behaviour.

Method for Evaluating Cortical Bone Young's Modulus: Numerical Twin Reconstruction, Finite Element Calculation, and Microstructure Analysis.

The determination of bone mechanical properties remains crucial, especially to feed up numerical models. An original methodology of inverse analysis has been developed to determine the longitudinal elastic modulus of femoral cortical bone. The method is based on a numerical twin of a specific three-point bending test. It has been designed to be reproducible on each test result. In addition, the biofidelity of the geometric acquisition method has been quantified. As the assessment is performed at the scale of a bone shaft segment, the Young's modulus values obtained (between 9518.29 MPa and 14181.15 MPa) are considered average values for the whole tissue, highlighting some intersubject variability. The material microstructure has also been studied through histological analysis, and bone-to-bone comparisons highlighted discrepancies in quadrants microstructures. Furthermore, significant intrasubject variability exists since differences between the bone's medial-lateral and anterior-posterior quadrants have been observed. Thus, the study of microstructures can largely explain the differences between the elastic modulus values obtained. However, a more in-depth study of bone mineral density would also be necessary and would provide some additional information. This study is currently being setup, alongside an investigation of the local variations of the elastic modulus.

Influence of build direction and heat treatment on the microstructure and tensile characteristics of cold metal transfer based wire arc additive manufactured SS 304L

Wire arc additive manufacturing has gained a noble position in the field of manufacturing metallic structures. This paper aims to evaluate the effect of build direction and heat treatment on the tensile behaviour along three different orientations: transverse (T), longitudinal (L), and diagonal (D). Microstructural investigations have been conducted to identify the microstructural features caused by CMT-based WAAM and its relation to mechanical properties. The results revealed a fine microstructure with austenite and ferrite phases and the formation of ferrite morphologies. For the untreated and treated specimens, respectively, the ferrite percentage was greater in the middle of the samples and is 12.29% and 11.21%. The WAAM components exhibited good tensile properties with a clear indication of anisotropic behaviour with respect to building direction. The diagonal specimen from WAAM and heat-treated WAAM resulted in better tensile properties. Additionally, it demonstrates a significant rise in Young's modulus value compared to the standard value for SS304L and other directional specimens in both treated and untreated circumstances. The percentage of anisotropy in WAAM and heat-treated specimen ranges from 6.42% to 57.76%. Fine microstructure creation and directional grain growth have produced resistance to slip movement in different orientations in different ways, resulting in the anisotropic behaviour of WAAM fabricated components.

Mechanical, antibacterial and cytotoxic characteristics of nanolayered TiNb–Zr–Ta and nitrogen-doped TiNb–Zr–Ta coatings

Titanium and titanium alloy materials are often made as medical implants. Surface properties of titanium medical implants play decisive roles for antibacterial and biological response and tissue biocompatibility. In this study, cathode arc evaporation (CAE) technology was used to deposit TiNb–Zr–Ta and nitrogen-doped TiNb–Zr–Ta coatings with nanostructures on the Ti–6Al–4V dental abutment screws. The deposited coatings were then oxidized at high temperature to produce different oxides on the surface of the coatings. The mechanical properties, antibacterial properties and biocompatibilities of the coatings were analyzed. The effect of coatings on the abutment screw loosening and removal torque between the abutment screw and the pure titanium implant fixture was studied by removal torque measurement. In addition, Staphylococcus aureus (S. aureus) was used for evaluating the antibacterial properties of coatings, and mouse fibroblasts (L929) were used for ISO 10993-5 cytotoxicity analyses to determine whether it had good biocompatibility.Nanolayered structures and multiphases of polycrystalline TiNb–Zr–Ta were obtained by co-deposition of Ta, Zr and TiNb. When small content of N was introduced, the TiNb–Zr–Ta(N) showed a polycrystalline TiNb–Zr–Ta where N atoms entered the metallic lattice at interstitial sites. After oxidation, oxide phases of Ta2O5, TiO2, Nb2O5 and ZrO2 were formed on the surface of TiNb–Zr–Ta and TiNb–Zr–Ta(N). Ta2O5 was obtained on the surface of the coating prior to other oxides such as TiO2, Nb2O5 and ZrO2. The deposited TiNb–Zr–Ta and TiNb–Zr–Ta(N) coatings had high contact angle and exhibited a hydrophobic feature, while the annealed TiNb–Zr–Ta–O and TiNb–Zr–Ta(N)–O showed hydrophilicity. The deposited TiNb–Zr–Ta had similar hardness and Young's modulus values to that of the uncoated Ti–6Al–4V. When N was doped, the TiNb–Zr–Ta(N) had the highest hardness and Young's modulus. The hardness of the annealed TiNb–Zr–Ta(N) coating only decreased slightly due to the small oxide layer of ∼140 nm. Compared with the uncoated Ti–6Al–4V, TiNb–Zr–Ta serial coatings deposited on abutment screws had higher removal torques, which prevented the abutment screw of dental implant from loosening after long-term use. The biocompatibility of TiNb–Zr–Ta serial coatings was similar to that of the uncoated Ti–6Al–4V. In addition, the oxidized TiNb–Zr–Ta and TiNb–Zr–Ta(N) coatings had excellent antibacterial properties. It is speculated that the resulting Ta2O5 of both coatings may inhibit bacterial growth and improve the antibacterial effect. Based on the above advantages, the TiNb–Zr–Ta serial coatings are expected to have the potential to be applied to biomedical implants.

Clinical Application of Ultrasound Elastic Imaging in Assessing Poststroke Complex Regional Pain Syndrome (CRPS).

This study aimed to explore the characteristics and clinical application of ultrasonic elastography in peripheral soft tissue in patients with poststroke complex regional pain syndrome (CRPS). Complex regional pain syndrome (CRPS) type I is also known as shoulder hand syndrome (SHS). Its main symptoms include shoulder pain, limited activity, upper arm, wrist, and knuckle joint pain. Ultrasonic elastic imaging technology is gradually being applied to musculoskeletal system evaluation, primarily for the elastic examination of superficial tissue, as a result of the continual advancements in ultrasound technology. To make up for the absence of conventional imaging, functional state evaluation of the motor system can offer conventional ultrasonic tissue elasticity and hardness data. The purpose of this study was to objectively quantify the soft tissue surrounding the shoulder joint of stroke patients with CRPS using ultrasonic elastic imaging and to determine the diagnostic usefulness of ultrasonic elastic imaging for CRPS in stroke in order to promote its usage in clinical practice. Patients diagnosed with CRPS following a stroke and admitted to the rehabilitation unit at Shanxi Bethune Hospital between January, 2021 to June, 2021 were included in the analysis. The control group consisted of people without pain in their shoulder joints. Each group consisted of 30 patients. A high-frequency wire array probe (frequency = 8-16 Hz) was employed in conjunction with an ultrasonic diagnostic apparatus. A quantitative analytic system determined Young's modulus of the tissue, while the tracking of the shear wave provided an elastin map in real-time. An excitation pulse of acoustic radiation force was used to cause shear waves in the tissue. The Young's modulus of supraspinatus muscle in the study and control groups was 289.16±22.07 Kpa and 231.99±23.61 Kpa, respectively (P <0.01). Young's modulus values of the study group's subscapular biceps were compared to those of the control group (P > 0.05). The supraspinatus shear wave elastographic (SWE) imaging value was 10.01±0.49 m/s in the study group and 7.92±0.50 in the control group (P <0.05). The study and control groups had subscapular muscle SWE values of 15.99±1.95 and 8.64±0.56 m/s, respectively (P <0.05). The average biceps tendon SWE value in the study and control groups was 6.39±0.42 and 4.69±0.36 m/s, respectively (P <0.05). In conclusion, the SWE assessed by ultrasound elastography is useful for early diagnosis and evaluation of the superior shoulder tendon, subscapular tendon, and biceps tendon of CRPS following stroke.

Assessment of Knee Menisci in Healthy Adults Using Shear Wave Elastography.

The aim of this study was to explore the application value of shear wave elastography in healthy adults with knee meniscus. One hundred adult subjects who underwent health checkups at our hospital from December 2022 to February 2023 were selected as research participants. Shear wave elastography was used to evaluate the periphery of the lateral and medial meniscus in both knees. To assess the mean differences in Young's modulus values between male and female groups, a one-way analysis of variance (ANOVA) and independent samples t-test were conducted. In addition, a Pearson correlation coefficient test was used to analyze the correlation between the elastic values of the meniscus and age, height, weight, and body mass index (BMI). There were no significant differences in elastic values between the lateral meniscus of the left and right sides or between the medial meniscus of the left and right sides within the same gender group (P > .05). Stiffness values of the medial meniscus were higher in each gender group than those of the lateral meniscus (P < .01). Additionally, males demonstrated higher stiffness values than females (P < .01). As age increased, the Young's modulus of the meniscus increased significantly (r > .75, P < .01). Shear wave elastography can serve as an adjunctive tool to aid in the assessment of knee meniscal elasticity.