Elastic Modulus Values Research Articles

Numerical Investigation of Flow Inside a Channel with Elastic Vortex Generator and Elastic Wall for Heat Transfer Enhancement

In the present investigation, a detailed numerical investigation of the flow and heat transfer characteristics of a channel with an elastic fin (vortex generator) and an elastic wall has been carried out using finite element method. The Fluid-Structure Interaction (FSI) model is used to capture the interaction between the fluid and the solid structure. A sinusoidal time dependent velocity profile has been imposed at the inlet of the channel and the right half of the upper wall of the channel is heated and exposed to constant temperature boundary condition. Due to the sinusoidal velocity profile at the inlet, the elastic fin oscillates periodically and act as a vortex generator, which causes more turbulence in the flow. The obtained results showed that the Nusselt number over the heated wall is affected by the position of the flexible fin, height of flexible fin and elasticity modulus of elastic fin. Moreover, due to the elasticity of the elastic wall and sinusoidal behavior of the inlet velocity, the elastic wall oscillates periodically upward and downward. The Nusselt number values over the heated wall are increased with decrease of the elastic modulus value of the elastic wall. However, the decrease in elastic modulus value of the elastic wall contributes to an increase in the pressure drop inside the channel. It should be added that the interplay between the fluid motion and the deformable structures leads to enhanced turbulence, as the flexible fin and elastic wall introduce additional disturbances and fluctuations into the flow regime. Consequently, this heightened turbulence level has profound implications for heat transfer processes within the system.

Antibonding valence states induce low lattice thermal conductivity in metal halide semiconductors

Reduction of phonon mediated thermal transport properties, i.e., lattice thermal conductivity (κL), of semiconductors can strongly affect the performance of thermoelectrics and optoelectronics. Although extrinsic routes to reduce κL have been achieved through selective scattering of phonons via doping, alloying, and hierarchical nano-structuring, semiconductors with intrinsically low κL have recently gained widespread attention due to their ability to decouple electronic and phonon transports. While innate low κL in crystalline semiconductors is a desired requirement to achieve high performance thermoelectrics, the solar upconversion efficiency of photovoltaics based on metal halide perovskites (MHPs) have been shown to increase due to their ultralow κL through the hot-phonon bottleneck effect. Therefore, understanding the microscopic mechanisms underlying ultralow κL in crystalline semiconductors is extremely important. Several structural factors that are intrinsic to a material have been shown to strongly influence the reduction of κL. Among them, the presence of rattling atoms, lone-pair electrons, and large lattice anharmonicity have been widely studied. Here, we bring out yet another largely unexplored intrinsic characteristic of materials related to the filled antibonding valence states (AVS) near the Fermi level, which are shown to induce low κL in crystalline compounds. We focus our review on an emerging class of compounds–metal halide semiconductors including MHPs and investigate the interplay between structures, chemical bonding and κL, carefully curating from literature a list of 33 compounds having different structure dimensionality with known κL. We established a universal connection between the elastic moduli, speeds of sound, and κL with the presence of AVS just below the Fermi level. We found that large peak in the AVS correlates positively with lower values of elastic moduli, speeds of sound, and κL, providing antibonding states based design criteria of low-κL compounds. Furthermore, we discuss different synthesis strategies, which are crucial for experimental realization of ultralow κL through structure manipulation. Additionally, we outline how chemical bonding data can be utilized in machine learning models for predictive modeling of κL. We hope that our approach of understanding low-κL through the viewpoint of chemical bonding theory would encourage exploration of phonon transport properties in other families of materials having filled AVS that can provide further insights on the structure-bonding-property relationships aiding novel materials design approaches.

In vivo study of pulmonary artery remodeling and pulsatility in long Fontan patient

Abstract Background Pulmonary vasculopathy associated with Fontan circulation is a relatively unexplored entity that could have clinical and therapeutic implications. Purpose Our aim was to evaluate the physiology of the pulmonary artery in patients with Fontan circulation using conventional right heart catheterization (RHC) and intravascular ultrasound (IVUS). Methods From December 2022 to January 2024, data from all consecutive Fontan patients undergoing RHC were prospectively collected at a tertiary referral center for adult congenital heart disease. Pressures and pulmonary artery wall high-definition IVUS recordings (OptiCrossTM, 60 MHz, Boston Scientific) were recorded at rest and during apnea. Pathological Fontan pressure was defined when as exceeding 15 mmHg. IVUS pulsatility index was defined as [(systolic lumen area - diastolic lumen area)/(diastolic lumen area) ×100], Peterson's elastic modulus as (pulmonary pulse pressure/IVUS pulsatility index), and area of wall thickness as [(wall area - lumen area)/(lumen area) x100)]. In the literature, the mean ± standard deviation (SD) normal values of elastic modulus and wall thickness area have been reported as 21 ± 1.7 mmHg and 1.4 ± 1.3%, respectively, in healthy patients without pulmonary hypertension (1: doi: 10.1186/s12931-017-0568-z). We define an alteration in intrinsic pulmonary arterial wall viscoelastic properties as an elastic modulus > 70 mmHg, and we define structural pulmonary wall remodeling as an increase in wall thickness area greater than 5%. Results 13 patients were studied. Median age was 28.1 years interquartile range (IQR) (25.6- 41.4), 7 (53.9%) were female, and 4 (30,8%) were in functional New York Heart Associtation (NYHA) class I. RHC and pulmonary arterial wall IVUS values are presented in Figure 1. 6 (46.2%) had Fontan abnormal pressures at rest. All patients showed minimal pulse pressure in the pulmonary arteries synchronized with heart rate, median pulmonary pulse pressure (IQR) 3 (2-4) mmHg. This pulsatility was detected in the IVUS study in all patients, pulsatility index (median (IQR) 4.8 (3.3-10.1)) and elastic modulus (median (IQR) 51.5 (20.5-101.6) mmHg). All of them had some degree of structural pulmonary wall remodeling (>5% wall thickness area), and 10 (76.9%) of them had marked remodeling (> 10%). The median (IQR) of wall thickness area was 13.6 (10.5-18.3) % (Figure 2). We think that the pseudo-normality of the elastic modulus is due to a low pulmonary pulse pressure, however, structural remodeling could be secondary to the endothelial dysfunction present and described in arteries with very low pulsatility. Conclusions The IVUS evaluation of the pulmonary artery in Fontan patients may be useful for revealing significant information regarding pulmonary physiology. Pulmonary wall thickening has been observed, providing insight into altered structural remodeling of the pulmonary arteries in this population.

Tailoring ZrWNb-Based Refractory High Entropy Alloys: A Multidirectional Characterization Through Elemental, Physical, Thermodynamic, and Nuclear Radiation Attenuation Properties

This study explores the development and characterization of 18 novel ZrWNb[(X)(Y)] (where XY are Hf, Ta, Mo, V, Ti) refractory high entropy alloys (RHEAs) designed to enhance mechanical robustness, thermodynamic stability, and radiation shielding effectiveness. Through a rigorous analysis, we evaluated the elastic modulus, entropy, and enthalpy of mixing, atomic size difference, valence electron concentration, and the omega parameter to understand the alloys’ phase behavior and structural integrity. Our findings revealed a broad range of elastic modulus values, indicating diverse mechanical adaptability suitable for high-stress applications. The thermodynamic assessment highlighted several RHEAs with favorable phase stability, particularly ZrWNbTaHf and ZrWNbTiTaHf, which are poised for high-performance usage due to their balanced mixing entropy and enthalpy. This study also benchmarks the RHEAs against conventional alloys, with sample R1 exhibiting the lowest fast neutron effective removal cross section, underscoring its superior neutron shielding capabilities. Additionally, R1 demonstrated exceptional photon attenuation, as evidenced by its competitive half-value layer performance across an extensive energy spectrum. Collectively, these results position R1 as a standout candidate, offering a significant advancement in materials science for applications demanding stringent radiation shielding, such as in nuclear reactor environments and space exploration.

Bayesian model averaging and Bayesian inference-based probabilistic inversion method for arch dam zonal material parameters

Inversion analysis based on structural monitoring data is an important part of evaluating the working behaviour of structures. In this paper, a probabilistic inversion method for the elastic modulus of concrete in arch dams based on Bayesian model averaging (BMA) and Bayesian inference is proposed. According to the measured displacement data of an arch dam project, the influence of the separation accuracy of water pressure component, the inversion method and the selection of displacement measuring points on the inversion results of the elastic modulus of the dam body is studied. Example analysis results show that the accuracy of the multi-measurement point displacement and hydraulic pressure component separation model based on BMA-HST (Hydrostatic-seasonal-time) is at least 18.97 % higher than that of the single measurement point, and the relative error of the elastic modulus value of the multi-measurement point zonal inversion based on the Polynomial chaos-Kriging (PCK) proxy model and the Bayesian inference is only 6 % at the maximum, which indicates that the inversion model described in this paper is able to realize the high-precision inversion analysis of the material parameters of the zonal analysis of concrete dams at a relatively low computational cost.

Bio-composites from barley, wheat, and cassava flours reinforced with oil palm residues: Characterization and tensile mechanical performance

This study explores the production of bio-composites from barley, wheat, and cassava flours, reinforced with varying ratios of oil palm residues. The research emphasizes principles of circular economy and sustainability. Both flours and reinforcements underwent characterization to elucidate how their physicochemical properties affect the mechanical behavior of the bio-composites. Barley flour exhibited significantly higher levels of protein (11.11 %), crude fiber (5.64 %), and ash (2.80 %) compared to wheat and cassava flours. Conversely, cassava flour stood out for its high carbohydrate concentration (approximately 97.8 % on a dry weight basis). Characterization highlighted enhanced adhesion between reinforcements in bio-composites with cassava flour, alongside morphological distinctions on fractured surfaces. Fourier-transform infrared (FTIR) analysis unveiled several functional groups in the bio-composites, while thermogravimetric analysis delineated five stages of thermal degradation. In terms of mechanical properties, bio-composites with barley flour showed higher elastic modulus values (970.5 MPa), while those with 12 % OPKS exhibited tensile strengths of 1.7–2.1 MPa. The interaction among components emerged as a fundamental factor influencing the mechanical properties of bio-composites, underscoring the necessity of considering reinforcement composition and distribution during fabrication.

ATP-induced reconfiguration of the micro-viscoelasticity of cardiac and skeletal myosin solutions.

We study the high-frequency, micro-mechanical response of suspensions composed of cardiac and skeletal muscle myosin by optical trapping interferometry. We observe that in low ionic strength solutions, upon the addition of magnesium adenosine triphosphate (MgATP2-), myosin suspensions radically change their micro-mechanics properties, generating a viscoelastic fluid characterized by a complex modulus similar to a suspension of worm-like micelles. This transduction of energy, from chemical to mechanical, may be related to the relaxed states of myosin, which regulate muscle contractility and can be involved in the etiology of many myopathies. Within an analogous generic mechanical response, cardiac and skeletal myosin suspensions provide different stress relaxation times, elastic modulus values, and characteristic lengths. These discrepancies probably rely on the dissimilar physiological functions of cardiac and skeletal muscle, on the different MgATPase hydrolysis rates of cardiac and skeletal myosins, and on the observed distinct cooperative behavior of their myosin heads in the super-relaxed state. In vitro studies like these allow us to understand the foundations of muscle cell mechanics on the micro-scale, and may contribute to the engineering of biological materials whose micro-mechanics can be activated by energy regulators.

Performance and mechanism of triethanolamine-triisopropanolamine corrosion inhibitor to deterioration of reinforced concrete under the coupling effect of freeze-thaw cycles and chloride attack

The purpose of this study is to propose an efficient and economical organic triethanolamine-triisopropanolamine corrosion inhibitor (OTTCI) to reduce the corrosion of steel in reinforced concrete. The influence of OTTCI on corrosion of steel in reinforced concrete under the coupling effect of freeze-thaw cycles and chloride attack (FTCs-CA) were characterized by electrochemical impedance spectroscopy (EIS), dynamic electrode potential (PDP), mechanical properties (mass loss rate (M), compressive strength (fn) and relative dynamic elastic modulus value (Pi)), capillary water absorption (CWA), bubble spacing coefficient (BSC) and scanning electron microscope (SEM). The inhibition mechanism of OTTCI was also analyzed and summarized. The results displayed that the dosage of OTTCI delayed the degradation of reinforced concrete under FTCs-CA. After 150 cycles, the M value of specimens with 1.0 % OTTCI reduced by 66.31 % compared to that of specimens without OTTCI, the Pi value increased by 51.9 %, and the polarization resistance and corrosion inhibition efficiency reached 2744.19 Ω cm2 and 92.88 %, respectively. In addition, OTTCI significantly reduced the CWA value and porosity. After 150 cycles, the CWA and porosity with 1.0 % OTTCI decreased by 60.1 % and 54.54 % respectively. The capillary water absorption coefficient increased linearly with the increase of FTCs-CA. SEM tests illustrated that OTTCI inhibited the development of internal cracks and macropores in concrete and promoted the formation of hydrated calcium silicate gels and calcite. The application of this study not only provides a new method to alleviate the deterioration of reinforced concrete, but also offers theoretical and technical support for further investigate on the deterioration characteristics of reinforced concrete in harsh environments.

Shear wave elastography to evaluate the effect of serum uric acid levels on carotid artery elasticity in patients with high-normal blood pressure

Background: Populations with normal high blood pressure often already have elevated blood uric acid levels and a higher chance of developing atherosclerosis, which accelerates the process of cardiovascular disease. The risk of atherosclerosis increases with thickening of the carotid artery intima-media, and changes in carotid artery elasticity precede intima-media changes, so early monitoring of carotid artery elasticity is of great significance in the prevention of cardiovascular disease. Using shear wave elastography (SWE) to evaluate the effect of serum uric acid (SUA) levels on carotid artery elasticity in patients with high-normal blood pressure (BP). Methods: One hundred and fifteen patients with high-normal BP were selected, and then divided into tertiles according to the SUA levels. The left carotid intima-media thickness (IMT), peak systolic velocity (PSV) and diameter of common carotid artery were measured by two-dimensional ultrasound and Doppler flow imaging. Longitudinal elasticity of the left anterior carotid wall was measured by SWE, including the mean values of the minimum elastic modulus (MEmin), maximum elastic modulus (MEmax) and mean elastic modulus (MEmean). Results: IMT, MEmean, MEmin and MEmax were obviously higher in the 3rd tertile (all P < 0.05), while there were no obviously different between the 1st tertile and 2nd tertile. Pearson correlation analysis showed positive correlations between SUA and SWE-related parameters, while there was no correlation with IMT. Multiple linear regression analysis found that age, systolic BP, and SUA levels were independently associated with SWE-related parameters. Conclusion: SWE will be more helpful than IMT in monitoring the effect of blood uric acid levels on carotid artery elasticity in patients with high-normal BP.

Enhancing auxetic gradient structures for hip joint implants to optimize stress shielding reduction

This study investigates the design and optimization of a porous hip implant to mitigate stress shielding. Initially, the focus was on determining the elastic modulus of a three-dimensional auxetic structure, primarily in the y-direction. Various methods—numerical, analytical, and experimental—were used to assess the elastic properties. Additive manufacturing was employed to create samples, which were then tested for their elastic properties through compression testing. The results revealed a strong correlation between the elastic modulus values obtained from simulations and experimental tests in the y-direction. To further enhance the implant’s performance and reduce stress shielding at the implant-bone interface, a gradient structure was introduced. This gradient design progressively increases the elastic modulus away from the bone contact surfaces, aligning closely with the bone’s modulus at the interface. The elastic modulus of this gradient structure was computed using Abaqus software and validated through analytical methods in MATLAB, with a minimal 4.8% difference between the two approaches, demonstrating high agreement. The application of a genetic algorithm enabled the creation of a porous hip implant tailored to minimize stress shielding throughout its structure. This innovative approach, integrating numerical, analytical, and experimental techniques with gradient structures, holds promise for improving hip implant performance and enhancing patient outcomes by reducing stress-shielding complications.

Combination of Different Sectional Elastography Techniques with Age to Optimize the Downgrading of Breast BI-RAIDS Class 4a Nodules.

This study aims to optimize the downgrading of BI-RADS class 4a nodules by combining various sectional elastography techniques with age. We performed conventional ultrasonography, strain elastography (SE), and shear wave elastography (SWE) on patients. Quantitative parameters recorded included age, cross-sectional and longitudinal area ratios (C-EI/B, L-EI/B), strain rate ratios (C-SR, L-SR), overall average elastic modulus values (C-Emean1, L-Emean1), five-point average elastic modulus values (C-Emean2, L-Emean2), and maximum elastic modulus values (C-Emax, L-Emax). Histopathological evaluations showed that out of 230 lesions, 45 were malignant, and 185 were benign. The sensitivity and specificity of conventional ultrasonography were 100% and 0%, respectively. In contrast, SE and SWE exhibited higher specificity but lower sensitivity. Crosssectional parameters (C-EI/B, C-SR, C-Emean1, C-Emean2, and C-Emax) outperformed their longitudinal counterparts, with C-SR and C-Emax showing the highest specificity (72.43% and 73.51%) and satisfactory sensitivity (80.00% and 88.89%). Combining age with C-SR and C-Emax significantly improved diagnostic efficiency, achieving a sensitivity of 97.78% and a specificity of 77.30%. Integrating age with C-SR and C-Emax effectively reduces unnecessary biopsies for most BI-RADS 4a benign lesions while maintaining a very low misdiagnosis rate.

High hydrostatic pressure processing of whole buckwheat grains to obtain functional gluten-free ingredients: Effect of pressure and holding time

High Hydrostatic pressure (HHP) represents an environmental-friendly and efficient non-thermal technology capable of inducing changes that can lead to functional improvements on starchy materials preserving the nutritional value of the original flours. The development of gluten-free (GF) flours and ingredients remain a challenge due to the need to improve the nutritional and techno-functional aspects of these commodities. Pre-soaked whole buckwheat (BW) grains were subjected to HHP treatment under different processing conditions: two pressure levels (300–600 MPa) and three holding times (0-5-15 min) to evaluate the techno-functional and nutritional response of the resulting flours. Significant (p < 0.05) increases in water absorption capacity and swelling capacity were observed in the flours resulting from longer treatment times (5–15 min) and the highest-pressure level (600 MPa). Higher thermal stability was also observed in the pasting profiles obtained for these flours. Flours resulting from HHP treatments at 600 MPa for 15 min also showed higher antioxidant capacity (DPPH and ORAC). The resulting flour from these processing conditions was used at different concentrations (15, 30, 50, and 70 %) in a GF bread formulation. An increase in the elastic modulus values of the doughs, the specific volume of the resulting bread and a reduction in the crumb firmness were observed in the formulations containing the BW-modified flour compared to the counterparts made with a native flour. Therefore, it can be concluded that the HHP treatment of whole buckwheat grains represents an interesting alternative for the development of ingredients with suitable technological and nutritional properties for gluten-free bakery formulations.

Effect of Areca Nut Fiber and Pineapple Leaf Fibers and Polyester Composition on Mechanical Properties of Composite

The Effect of Areca Nut Fiber and Pineapple Leaf Fibers and Polyester Composition on Mechanical Properties of Composite Diva Akbar*, Dody Yulianto Mechanical Engineering Study Program, Faculty of Engineering, Islamic University of Riau Jl. Kaharuddin Nasution Km 11 No.113 Perhentian Marpoyan, Pekanbaru Telp. 0761 – 674635 Fax. (0761) 674834 Email : divaakbar@student.uir.ac.id ABSTRACT Areca nut fiber and pineapple leaf fiber are types of fiber derived from natural fibers that are interesting to research as composite reinforcing fibers because currently they are very abundantly available. This research aims to make composite boards made from areca nut fiber and pineapple leaf fiber with polyester resin metrics for mechanical strength. This research varied different mixtures starting from areca nut fiber: pineapple leaf fiber: polyester resin, namely 20%: 30%: 50%, 25%: 25%: 50%, 30%: 20%: 50% using The hand lay up method was carried out three times in making composite board specimens. The highest bending strength results in sample one with a mixture of 20% areca nut fiber, 30% pineapple leaf fiber and 50% polyester resin were 52.60 Mpa, the impact value was 0.379 Joules/mm2. This is because there is the influence of the fiber and metric mixture which causes the elasticity modulus value to increase and because there is the influence of fiber density, where the smaller the density value the greater the mechanical strength, both bending strength and impact value. This phenomenon can be seen from macro observations, namely that composite boards experience fiber pull out with a fibrous brittle fracture type.

Impacts of Backcalculation Software Selection on Airport Flexible Pavements Using the Aircraft Classification Rating/Pavement Classification Rating Method

From November 2024, the aircraft classification rating/pavement classification rating (ACR/PCR) method will be accepted by civil aviation authorities to notify the bearing capacity of airport pavements. Structural characteristics are necessary to calculate the parameters relating to this method, such as the modulus of elasticity which, in the case of existing pavements, can be obtained by backcalculation. However, the results of this procedure may vary depending on the type of method and algorithms used to minimize adjustment errors between the deflection basins adopted in the software. Given the above, this article aims to evaluate whether the choice of backcalculation software affects the resistance classification and admissibility of aircraft on airport pavements using the ACR/PCR method based on the backcalculated elastic moduli. The elastic modulus values of the materials from two runways were backcalculated using BAKFAA, BackCAP, BackMedina, and ELMOD software, and then used to calculate the PCR. The results of the backcalculation showed differences in the elastic moduli obtained by the software, mainly in the subgrade. It was found that the backcalculation software used can limit the type of aircraft and the runway resistance. Therefore, the choice of software for backcalculation of deflection basins can influence the results of the ACR/PCR method because of divergences in determining the resistance of the pavement’s bearing capacity and the admissibility of aircraft operations in the analyzed structures.

Development of hydroxyapatite/poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate)/gelatin composite nanofibers to improve bone‐forming cell proliferation and mineral deposition

AbstractCalcium phosphate hydroxyapatite (HA) was successfully incorporated into poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate)/gelatin (PHBV/GEL) nanofibers through an electrospinning process in a hexafluoroisopropanol solvent (HFIP). The PHBV/GEL was electrospun and collected using a rotating metallic network to develop highly ordered nonwoven mats. The effects of HA addition on the morphologies of the obtained fibers were investigated using SEM. The average diameter of the fibers ranged around 700–900 nm, depending on the HA content. From a mechanical perspective, the addition of HA nanoparticles showed variations in tensile strength and elastic modulus values. The lowest tensile strength measured for neat PHBV/GEL was 0.37 ± 0.08 MPa with an elastic modulus of 9.45 ± 0.65 MPa, whereas the highest tensile strength reported for 5% HA‐loaded PHBV/GEL mats was 1.1 ± 0.4 MPa with an elastic modulus of 16.9 ± 0.39 MPa. In addition, cell viability, and mineral deposition were also studied using MC3T3‐E1 pre‐osteoblasts. The in vitro experiment results showed that the HA loaded‐PHBV/GEL mats provide optimal conditions for cell growth and osteogenic differentiation of MC3T3‐E1 cells. This study reveals the potential of PHBV/GEL/HA matrices in the development of novel guided bone‐regeneration (GBR) membranes for orthopedic and craniomaxillofacial surgery, by providing favorable structural features for attachment, growth, and differentiation of osteoblast cells.Highlights Simple and cheap electrospinning strategy toward network‐like fibrous mats. Microstructure, mechanical, and biological features were evaluated. Electrospun PHBV/GEL/HA promoted calcium phosphate deposition by MC3T3‐E1 cells.

Modeling acoustic characteristics of artificial bone alloys for medical and surgical use under thermodynamic conditions

The study examines the impact of porosity on mechanical, acoustic, and behavioral properties of (Ti-6Al-4 V alloy) alloys, which are manufactured to mimic human bones. It investigates how porosity, controlled through factors like pressure, particle size, and temperature during sintering, affects properties such as modulus of elasticity, surface acoustic wave (SAW) velocities, hardness coefficients, and acoustic resistance.The findings suggest that different levels of porosity at varying sintering temperatures significantly alter the dynamic elastic modulus of the alloys. Specifically, increasing porosity values seem to correlate with a decrease in elastic constants, elastic modulus values, and surface acoustic wave types. This phenomenon may be attributed to the transitional crystalline structure phases of Ti6Al4V alloy and the manufacturing process.Remarkably, the study concludes that these (Ti-6Al-4 V alloy) alloys exhibit superior porosity, mechanical, and acoustic qualities compared to various types of human bone, including cortical, trabecular, and cancellous bone.

DEVELOPMENT OF A CORRELATION MODEL FOR TORSIONAL SHEAR MODULUS PROPERTIES BETWEEN STRUCTURAL SIZE SPECIMENS BASED ON EN 384:2016 AND SMALL CLEAR SPECIMENS (MS544: PART 2)

In timber design, the shear modulus of beams is crucial for ensuring torsional stability and minimizing vibrational issues. Traditionally, the ratio of modulus of elasticity (E) to shear modulus (G) is assumed to be 16:1. However, bending tests often combine flexural and shear stresses, making it difficult to assess pure shear properties. The British Standard BS EN 408:2012 now recommends the torsion test as the preferred method for determining the shear modulus of structural-size timber and timber composites. This method has received limited attention in Malaysia. This study investigates the torsional shear modulus of Malaysian tropical timber species across different strength groups (SG), including Balau (SG1), Kempas (SG2), Kelat (SG3), Kapur (SG4), Resak (SG4), Keruing (SG5), Mengkulang (SG5), Light Red Meranti (SG6), and Geronggang (SG7). Torsion tests were conducted in line with BS EN 408, and the results were compared with modulus of elasticity values from MS554: Part 2. The findings showed that the E to G ratio for these species ranged from 17:1 to 29:1, with an average of 21:1—exceeding the conventional 16:1 ratio. This indicates that torsional shear modulus must be experimentally tested rather than inferred from the traditional ratio.

Assessment of perineal body properties in women with stress urinary incontinence using Transperineal shear wave elastography

Limited data on the correlation between the perineal body (PB) and stress urinary incontinence (SUI) are available. The objectives of this study were to quantify the PB using shear wave elastography (SWE) technology with a high-frequency linear array probe to evaluate the relationship between the properties of PB and stress urinary incontinence (SUI). This study included 64 women with SUI and 70 female control participants. The length, height, perimeter, and area of PB in all participants were calculated using transperineal ultrasound, and the elasticity of PB was assessed by SWE at rest and during the maximal Valsalva maneuver, respectively. In addition, the comparison of PB parameters between the patients with SUI and the healthy participants was conducted. The transperineal ultrasound and SWE examination was performed in 134 participants, and the elastic modulus values were significantly increased from participants at rest to those during the maximal Valsalva maneuver in all participants (Emax: 35.59 versus 53.13 kPa, P < 0.001; and Emean: 26.97 versus 40.25 kPa, P < 0.001). Emax and Emean of PB exhibited significant differences during the maximal Valsalva maneuver between the SUI group and the control group (47.73 versus 58.06 kPa, P < 0.001; and 35.78 versus 44.33 kPa, P < 0.001) and had a negative correlation with SUI. The BMI and PB height during the maximal Valsalva maneuver in the SUI group were found to be significantly higher than that in healthy volunteers. Emax and Emean of PB negatively correlated with BMI during the maximal Valsalva maneuver (r = -0.277, P = 0.001 and r = -0.211, P = 0.014). ROC curve analysis demonstrated that PB perimeter of less than 12.68mm was strongly associated with SUI during the maximal Valsalva maneuver, and an Emax of less than 55.76 kPa had a 100% specificity in predicting SUI. SWE can quantify the elasticity of PB, identifying a significant difference between participants at rest and during Valsalva maneuver. In addition, the stiffness of the PB was significantly lower in women with SUI than in healthy women, which may provide a noninvasive clinical practice in SUI prediction.

Application of Shear Wave Elastography in the Diagnosis and Evaluation of Cervical Cancer

Background: Our goal was to add an auxiliary examination method for the detection of cervical cancer, and to further explore its application value in clinical staging and treatment. Methods: Shear wave elastography (SWE) technique was used to examine the cervical hardness of patients, and the maximum, mean and minimum values of elastic modulus were recorded, with differences being compared. The area under the receiver operating characreristic (ROC) curve and diagnostic efficacy of elastic modulus were compared with Medcalc software. The differences of elastic modulus values under different parameters were compared in the cervical cancer group. Results: The mean, maximum and minimum values of the cervical cancer group were all the highest, and the differences were statistically significant. The area under the ROC curves were 0.925, 0.909 and 0.873, respectively. For the mean and maximum values, the Youden indexes were 0.79 and 0.72, the positive likelihood ratios were 21.74 and 19.97, and the negative likelihood ratios were 0.18 and 0.25. The optimal cut-off point was 82.2 kilpoascal (kPa) for maximum value and was 66.5 kPa for mean value. Elastic modulus were all significantly different according to International Federation of Gynecology and Obstetrics (FIGO) stages and tumor lesion size. Also, elastic modulus of cervical cancer patients before and after radiotherapy were statistically significant. Conclusions: SWE technology has an application value in the detection of cervical cancer. The mean and maximum values have higher diagnostic accuracy. SWE technology also has potential clinical application value in the clinical staging and treatment of cervical cancer, but further studies with larger sample sizes are needed.

Rheological properties of model emulsions containing oleosomes

AbstractIn the presented research, oleosomes were obtained from unroasted hazelnuts in an aqueous environment with a pH of 9.5, adjusted using sodium bicarbonate. Model emulsions were then prepared to contain oleosomes in proportions of 15, 25, and 35%. Rheological and viscosity analyses were conducted on these model emulsions, focusing on elastic and viscous modulus values. The results of the analyses, which revealed that an increase in the oleosome content in the model emulsions correlated with a concurrent increase in emulsion viscosity as well as in the elastic (G′) and viscous (G″) moduli, demonstrate the significant impact of oleosome concentration on the rheological properties of the emulsions. All samples exhibited a G′ &gt; G″ relationship, indicating their semi-solid nature. Moreover, an increase in the oleosome content was found to result in a higher consistency index for the product, while the flow index remained largely unchanged.