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Aims: The COVID‐19 infection has been described as affecting myocardial injury. However, the relation between left ventricular global longitudinal strain (GLS), global circumferential strain (GCS) and global radial strain (GRS), disease severity and all‐cause mortality in COVID‐19 is unclear. Methods and Results: The study consisted of 220 patients with COVID‐19, including 127 (57.5%) with mild, 43 (19.5%) with moderate and 50 (22.7%) with severe/critical conditions. Myocardial dysfunction was analysed by GLS, GCS and GRS using two‐dimensional speckle‐tracking echocardiography. Hazard ratios and Kaplan–Meier curves were produced to assess the association between strains and cardiac biomarker indices with a composite outcome of all‐cause mortality. With an average follow‐up period of 11 days, 19 patients reached the endpoint (death). Significant associations were found for the three strain parameters and the levels of blood urea nitrogen (BUN) (r = 0.206, 0.221 and 0.355, respectively). Cardiac troponin I (cTnI) was closely related to the GLS and GCS (r = 0.240 and 0.324, respectively). In multivariable Cox regression, GCS > −21.6% was associated with all‐cause death {hazard ratio, 4.007 [95% confidence interval (CI), 11.347–11.919]}. Conclusions: GLS, GCS and GRS are significantly related to myocardial dysfunction in patients with COVID‐19. Worsening GCS poses an increased risk of death in COVID‐19. [ABSTRACT FROM AUTHOR]

This paper presents the design of a strain-sensitive, dual ball-shaped tunable zone (DBT) taper structure for light intensity modulation. Unlike conventional tapered optical fibers, the DBT incorporates a central light field modulation zone within the taper. By precisely controlling the fusion parameters between single-mode fiber (SMF) and polarization-maintaining fiber (PMF), the ellipticity of the modulation zone can be finely adjusted, thereby optimizing spectral characteristics. Theoretical analysis based on polarization mode interference (PMI) coupling confirms that the DBT structure achieves a more uniform spectral response. In cantilever beam strain tests, the DBT exhibits high sensitivity and a highly linear intensity–strain response (R² = 0.99), with orthogonal linear polarization mode interference yielding sensitivities of 0.049 dB/με and 0.023 dB/με over the 0–244.33 με strain range. Leveraging the DBT's light intensity sensitivity, a temperature-compensated intensity difference and ratio calculation method is proposed, effectively minimizing the influence of light source fluctuations on sensor performance and enabling high-precision strain measurements with errors as low as ±6 με under minor temperature variations. The DBT fiber device, combined with this innovative demodulation technique, is particularly suitable for precision optical sensing applications. The DBT structure, combined with the novel demodulation method, is particularly well-suited for high-precision and stable measurements in industrial monitoring, aerospace, civil engineering, and precision instruments for micro-deformation sensing. [ABSTRACT FROM AUTHOR]

Key message: Repeated bending stimulations applied on poplar stem drives wood formation toward egg-shaped cross sections, thicker fiber cell walls and more fibers developing a G-layer; but cells sensitivity accommodates to avoid overresponses. Trees acclimate to mechanical stimulations (e.g. wind) through thigmomorphogenesis. Recent studies have demonstrated that repetitive unidirectional bending treatments applied to poplar stems result in the production of two distinct types of wood: tensile flexure wood (TFW) on the stretched side and compressive flexure wood (CFW) on the compressed side of the stem. However, the dose-effect responses of wood formation to repeated unidirectional bending treatments have not been established. In this study, we show that the number of bending events plays a crucial role in wood formation. To investigate this, young poplar stems were subjected to two different treatments involving different numbers of transient and unidirectional elastic bends. The radial growth of the stems was monitored throughout the treatments, and wood anatomy was quantitatively analysed and compared to control trees. The elliptic shape of poplar stem cross section, observed in response to the lowest dose, transformed into egg-shaped cross section in response to the highest dose. At the tissue level, the proportion of vessels vs fibers and their sizes were not differentially altered between the two treatments. However, there were notable differences in the proportion of G-fibers and the thickening of secondary cell walls, showing that the different traits of flexure wood have independent mechanosensitive control. Overall, our findings demonstrate that, in addition to their ability to respond to the intensity and direction of local mechanical strains, poplars adjust wood formation based on the number of bending events. These modifications likely enhance stem resistance against breakage when exposed to strong wind gusts. [ABSTRACT FROM AUTHOR]

Featured Application: Towing systems are largely used in the automotive industry. They must respect some requirements defined by the standards. These important systems for cars are studied in this paper in order to improve safety in transportation. The authors present the possibility to use other materials for towbars and formulate a series of practical recommendations obtained as a result of extended studies on towing systems. This paper aims, in the context of the need to reduce the weight and price of vehicles, to present theoretical and experimental results regarding towing systems made of alternative materials (fibrous composite materials and aluminum alloys). The study of the main element of the whole system, namely towbar research, was stressed, presenting comparative results. The FEM will be used to obtain the stress and strain field in the towball and the towing system. The experimental tests validate the theoretical results obtained. This paper studies five towing systems made by different materials and finally presents a series of practical recommendations, useful in the industry, regarding the improvement of the analyzed models. [ABSTRACT FROM AUTHOR]

Rail corrugation is a common form of rail damage discovered when servicing heavy-haul railways that seriously affects the safety of wheel–rail systems. To determine the characteristics of the deterioration of a corrugated heavy-haul railway, this study used ABAQUS simulation software to establish a three-dimensional elastic–plastic wheel–rail finite element model. We then simulated the stress and strain distributions of wheel–rail contact spots as C80 freight cars pass through various corrugated sections of heavy-haul railways, featuring different wavelengths and wave depths. The simulation results demonstrated that the stress and strain increase from the peak positions to the troughs, reaching a maximum somewhere behind the troughs, and then decreasing to the next peak. The stress and strain increase as the depth of corrugation increases. The wheel–rail contact exhibits a maximum stress of 1.312 to 1.770 GPa, and the maximum strain is 0.6470% to 0.9897%. Wheel–rail contact stress and strain occur at a maximum of 8–40 mm after the troughs, rather than at the trough position, forming "planing and rolling" effects. This mechanism revealed by the variation in the stress and strain distributions in this study provides a reference for the in-depth analysis of rail corrugation deterioration and for the exploration of the mechanisms of corrugation deterioration of heavy-haul railways. [ABSTRACT FROM AUTHOR]

Background: The application value of myocardial work (MW) in evaluating myocardial function and predicting major adverse cardiovascular events (MACE) in maintenance hemodialysis (MHD) patients has not been fully explored. Purpose: Comparing noninvasive MW parameters between MHD patients and healthy controls, and further determining its value in predicting MACE in MHD patients. Methods: A prospective single‐institution study included 92 MHD patients without prior cardiovascular disease and 40 age‐ and sex‐matched healthy controls. Conventional echocardiographic data, global longitudinal strain (GLS), and MW parameters (global work index [GWI], global constructive work [GCW], global work efficiency [GWE], global wasted work [GWW]) were derived and compared between MHD and the control. Logistic regression was used to determine the predictive value of these parameters for MACE. The receiver operating characteristic curve was utilized to compare the predictive differences of MACE between GWE and GLS. Results: Compared with healthy individuals, MHD patients had significantly reduced GWE, GLS and elevated LVMI, GWW (all p < 0.001), while there was no significant difference in left ventricular ejection fraction. Twenty eight (30%) MHD patients experienced MACE. Two nested models adding GWE and GLS, respectively, showed that age (p < 0.005), GWE (p = 0.034), and GLS (p = 0.014) were independent predictors of MACE. The AUC derived from GWE for predicting MACE was significantly higher than that derived from GLS (0.836 vs. 0.743, p = 0.039). Conclusions: Myocardial work is a novel tool for assessing left ventricular myocardial performance in MHD patients. GWE is an independent predictor of MACE. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymer (FRP) composites are promising materials already being used in bridge construction. Lightweight deck panels, mainly used in the rehabilitation or replacement of existing bridges, are the most commonly used FRP bridge components. However, FRP decks are prone to damage due to delamination, matrix cracking, interlaminar cracking, and debonding. In addition, due to their microstructure, FRP materials tend to deteriorate in ways that are not easily detected by visual inspection. Therefore, nondestructive methods should often complement visual inspections aimed at assessing the technical condition of the structure. New measurement techniques are constantly being researched and developed to assist in the evaluation of FRP structures. Distributed fiber optic sensing (DFOS) has been chosen as the main measurement technique of the newly developed FRP bridge deck panel because this technique provides extended advantages compared to the conventional spot gauges. The concept of a component with an integrated DFOS-based system capable of structural control and detection of overloaded vehicles has been developed and verified both in laboratory conditions. The novelty of the presented approach is that sensors (strain-sensing fibers) are precisely embedded in FRP laminates for simultaneous internal strain and vertical displacement (shape change) measurements and delamination detection. The experimental verification of a full-scale deck under static and dynamic loading is described in the paper. The performance of the DFOS system was verified using reference techniques. The results proved the system to be a reliable tool for diagnosing FRP bridge decks. [ABSTRACT FROM AUTHOR]

The deformation mechanism of SiC reinforced 6061 aluminium-based metal matrix composites (MMCs) under compression is investigated in this study. Finite element analysis was used to examine the impacts of particle size, shape, and content on the stress distribution, stiffness, and strength of MMCs. To identify potential locations of debonding or material failure, the major stress and von Mises strain distributions were displayed. It was found that at 10% reinforcement content the effects of particle size and shape were negligible, however there was an increase in material strength over the monolithic material. The greatest increase to mechanical properties occurred at 20% particle content with the smallest size particle. This was due to an increase in load transfer to the stiffer particles because of increased surface contact length. The reinforcing particles also improved the resistance to matrix material flow. Circular, triangular, square, and rectangular particles were tested. Because of its more evenly distributed strain and greater areas of minimal strain in the matrix material, the rectangular particle provided the highest increase in mechanical characteristics. [ABSTRACT FROM AUTHOR]

Background: The immediate impact of catheter ablation on left atrial mechanical function and the timeline for its recovery in patients undergoing ablation for atrial fibrillation (AF) remain uncertain. The mechanical function response to catheter ablation in patients with different AF types is poorly understood. Methods: A total of 113 AF patients were included in this retrospective study. Each patient had three magnetic resonance imaging (MRI) studies in sinus rhythm: one pre-ablation, one immediate post-ablation (within 2 days after ablation), and one post-ablation follow-up MRI (≤ 3 months). We used feature tracking in the MRI cine images to determine peak longitudinal atrial strain (PLAS). We evaluated the change in strain from pre-ablation, immediately after ablation to post-ablation follow-up in a short-term study (< 50 days) and a 3-month study (3 months after ablation). Results: The PLAS exhibited a notable reduction immediately after ablation, compared to both pre-ablation levels and those observed in follow-up studies conducted at short-term (11.1 ± 9.0 days) and 3-month (69.6 ± 39.6 days) intervals. However, there was no difference between follow-up and pre-ablation PLAS. The PLAS returned to 95% pre-ablation level within 10 days. Paroxysmal AF patients had significantly higher pre-ablation PLAS than persistent AF patients in pre-ablation MRIs. Both type AF patients had significantly lower immediate post-ablation PLAS compared with pre-ablation and post-ablation PLAS. Conclusion: The present study suggested a significant drop in PLAS immediately after ablation. Left atrial mechanical function recovered within 10 days after ablation. The drop in PLAS did not show a substantial difference between paroxysmal and persistent AF patients. [ABSTRACT FROM AUTHOR]

Gradient ratio tests were conducted to investigate the filtration behaviour of staple fibre needle-punched nonwoven geotextiles subjected to unequal biaxial tensile strains. Three groups of biaxial tensile strains were designed, with the ratios of the strain in the machine direction to that in the cross-machine direction set to 1, 2, and 4, respectively. The strains in the machine direction in the three groups were the same, ranging from 10% to 30%. The tested filtration properties included the gradient ratio (GR), permeability of the soil-geotextile system, mass of soil loss, and permittivity of the pure geotextiles. Comparisons were made between the filtration properties of staple fibre (SN) geotextiles and continuous filament (CN) geotextiles. It is shown that for a certain strain ratio, the GR value at the time of test termination increases with increasing strain, and the permeability of the soil-geotextile system, soil loss, and permittivity of the pure geotextiles decrease with increasing strain. The soil loss and permittivity under equal biaxial tensile strains tend to be higher than those under unequal biaxial tensile strains. The CN geotextiles have better retention capability and more clogging potential for the tested soils than the SN geotextiles for a similar mass per unit area. [ABSTRACT FROM AUTHOR]

We report the first conductance measurements of [n]staffane (bicyclopentane) oligomers in single‐molecule junctions. Our studies reveal two quantum transport characteristics unique to staffanes that emerge from their strained bicyclic structure. First, though staffanes are composed of weakly conjugated C−C σ‐bonds, staffanes carry a shallower conductance decay value (β=0.84±0.02 n−1) than alkane chain analogs (β=0.96±0.03 n−1) when measured with the scanning tunneling microscopy break junction (STM‐BJ) technique. Staffanes are thus more conductive than other σ‐bonded organic backbones reported in the literature on a per atom basis. Density functional theory (DFT) calculations suggest staffane backbones are more effective conduits for charge transport because their significant bicyclic ring strain destabilizes the HOMO‐2 energy, aligning it more closely with the Fermi energy of gold electrodes as oligomer order increases. Second, the monostaffane is significantly lower conducting than expected. DFT calculations suggest that short monostaffanes sterically enforce insulating gauche interelectrode orientations over syn orientations; these steric effects are alleviated in longer staffanes. Moreover, we find that [2‐5]staffane wires may accommodate axial mechanical strain by “rod‐bending”. These findings show for the first time how bicyclic ring strain can enhance charge transmission in saturated molecular wires. These studies showcase the STM‐BJ technique as a valuable tool for uncovering the stereoelectronic proclivities of molecules at material interfaces. [ABSTRACT FROM AUTHOR]

This study mainly focused on the hot-stretching-induced oriented crystallization structure of isotactic polypropylene (iPP) granules specialized for capacitance films (i. e. electrical grade iPP). A series of characterization tools, including differential scanning calorimetry, wide-angle X-ray diffraction, two-dimensional small-angle/wide-angle X-ray scattering, and dynamic mechanical analysis, were employed to determine the long-period spacing, orientation degree, crystallinity, melt point and chain relaxation behavior of iPP. The stretching deformation resulted in a highly oriented fibrillar morphology. A strain-induced crystallization enhancement was observed, in which both of the orientation degree and crystallinity increased continuously with an increasing in the strain. Two types of lamellae with thicker or thinner thicknesses were newly formed during the hot-stretching process. The thicker one can be attributed to the melt-recrystallization mode, while the thinner one is ascribed to the strain-induced crystallization mechanism. The dependence of strain on their crystallinity and melt point seemed to be weak. Moreover, the electric density difference between the amorphous and crystalline phases decreased with an increase in the strain, and meanwhile the chain relaxation temperatures related to different condensed states became close to each other. [ABSTRACT FROM AUTHOR]

Metal thiophosphates (MTPs) are a large family of 2D materials that exhibit large structural and chemical diversity. They also show promise for applications in energy harvesting and photodetection. Strain and defect engineering have previously been demonstrated as useful mechanisms to tune several properties of MTPs such as resistivity, magnetic state, and electronic band gap. However, the effect of these stimuli on engineering tunable light emission in MTPs remains unexplored. Here, it is experimentally demonstrated that sulfur vacancies in metal thiophosphate AgScP2S6${\rm AgScP_{2}S_{6}}$ allow defect‐state‐to‐valence‐band transitions leading to visible light emission at sub‐bandgap energies, while structural defects in the material can enhance and modulate the photoluminescence spectrum. It is also showed that the structural‐defect‐enhanced light emission can be further tuned by temperature‐induced strain gradients. [ABSTRACT FROM AUTHOR]

Capillarity-driven transport in nanoporous solids is widespread in nature and crucial for modern liquid-infused engineering materials. During imbibition, curved menisci driven by high negative Laplace pressures exert an enormous contractile load on the porous matrix. Due to the challenge of simultaneously monitoring imbibition and deformation with high spatial resolution, the resulting coupling of solid elasticity to liquid capillarity has remained largely unexplored. Here, we study water imbibition in mesoporous silica using optical imaging, gravimetry, and high-resolution dilatometry. In contrast to an expected Laplace pressure-induced contraction, we find a squareroot-of-time expansion and an additional abrupt length increase when the menisci reach the top surface. The final expansion is absent when we stop the imbibition front inside the porous medium in a dynamic imbibition-evaporation equilibrium, as is typical for transpiration-driven hydraulic transport in plants, especially in trees. These peculiar deformation behaviors are validated by single-nanopore molecular dynamics simulations and described by a continuum model that highlights the importance of expansive surface stresses at the pore walls (Bangham effect) and the buildup or release of contractile Laplace pressures as menisci collectively advance, arrest, or disappear. Our model suggests that these observations apply to any imbibition process in nanopores, regardless of the liquid/solid combination, and that the Laplace contribution upon imbibition is precisely half that of vapor sorption, due to the linear pressure drop associated with viscous flow. Thus, simple deformation measurements can be used to quantify surface stresses and Laplace pressures or transport in a wide variety of natural and artificial porous media. [ABSTRACT FROM AUTHOR]

Strain engineering serves as an effective method for optimizing electronic and optical properties in semiconductor devices, with applications including the enhancement of optical emission in Ge and GeSn‐based devices, improvement of carrier mobility, and second harmonic generation in silicon photonics structures. Current methods for deformation characterization in semiconductors, such as X‐ray diffraction and Raman spectroscopy, often require bulky and expensive setups and are limited in vertical resolution. Consequently, techniques capable of measuring lattice strain while overcoming these drawbacks are highly desirable. This study proposes a proof of concept for a cost‐effective, compact, fast, and non‐destructive approach to probe non‐uniform strain fields and additional material properties by exploiting the bulk photovoltage effect. The method is benchmarked with an array of silicon nitride stripes deposited under varying pressure conditions on a germanium substrate. Initially, their surface strains are verified through Raman spectroscopy. The deformations are replicated in a finite element method platform by integrating mechanical simulations with deformation potential theory, thereby estimating the band edge energy landscape. Finally, the study discusses the theoretical behavior of the photovoltage signal, considering semiconductor properties, defects, doping, and deformation. The findings offer insights into the development of advanced techniques for strain and transport analysis in semiconductor materials. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) magnetic materials show potential for the advancement of high-density, energy-efficient electronic and spintronic applications in future memory and computation. Here, by using first-principles density functional theory (DFT) calculations, we predict a new 2D Janus nitride MXene MnCrNO2 monolayer. Our results suggest that the optimized MnCrNO2 monolayer possesses a hexagonal structure and exhibits good dynamical stability. The intrinsic monolayer MnCrNO2 exhibits semiconductive properties and adopts a ferromagnetic ground state with an out-of-plane easy axis. It can sustain strain effects within a wide range of strains from −10% to +8%, as indicated by the phonon dispersion spectra. Under the biaxial tensile strain, a remarkable decrease in the bandgap of the MnCrNO2 is induced, which is attributed to the distinct roles played by Mn and Cr in the VBM or CBM bands. Furthermore, when the compressive strain reaches approximately −8%, the magnetic anisotropy undergoes a transition from an out-of-plane easy axis to an in-plane easy axis. This change is mainly influenced by the efficient hybridization of the d orbitals, particularly in Mn atoms. Our study of the Janus MXene MnCrNO2 monolayer indicates its potential as a promising candidate for innovative electronic and spintronic devices; this potential is expected to create interest in its synthesis. [ABSTRACT FROM AUTHOR]

Background: A positive work environment can enhance nursing safety and patient satisfaction while alleviating nurse stress. Conversely, a poor work environment can harm nurses' physical and mental health and compromise the quality of care, particularly in the high-intensity and shift-based setting of the ICU. Objectives: Based on the Job demands-resources (JD-R) model, this study examined the effects of job demands and job resources in the work environment, as well as personal resources, on the night-shift alertness of ICU shift nurses. Methods: This cross-sectional correlational exploratory study, conducted from July to September 2022, recruited 291 ICU shift nurses from a hospital in Beijing, China. The Copenhagen Psychosocial Questionnaire (COPSOQ), the Self-resilience scale, the General Self-Efficacy Scale (GSES), and the Psychomotor Vigilance Task (PVT) were used to subjectively and objectively measure the job demands, job resources, personal resources, and night-shift alertness. SPSS 26.0 and Mplus 8.3 were used to analyze the data and construct the structural equation model. Results: The night-shift reaction time was 251.0 ms (Median), indicating a relatively high level of alertness. Job demands were negatively correlated with both job resources (r=-0.570, P < 0.001) and personal resources (r=-0.462, P < 0.001), while a positive correlation existed between job resources and personal resources (r = 0.554, P < 0.001). The results show that increased job demands can lead to higher levels of nurse strain (β = 0.955, P < 0.001), whereas job resources were found that it can decrease strain (β=-0.477, P = 0.047). Adequate job resources can enhance motivation directly (β = 0.874, P < 0.001), subsequently reducing reaction time (β=-0.148, P = 0.044) and improving night-shift alertness among ICU shift nurses. Conclusion: Enhancing ICU shift nurses' work motivation through bolstering job resources can boost night-shift alertness. However, it is noteworthy that, in this study, neither strain nor individual resources significantly influenced nurses' night-shift alertness. This may be attributed to the complexity of the ICU environment and individual differences. Future research should explore the relationship between these factors and nurses' work alertness. [ABSTRACT FROM AUTHOR]

In this work, the effects of magnetic proximity coupling on electronic structures, valley polarization and magneto-crystal anisotropy of VI3/WSe2 heterostructure are studied in detail based on density functional theory. The results show that the spin-valley polarization characters of WSe2 monolayer can be induced by the proximity effect of ferromagnetic VI3 monolayer. Based on the effective Hamiltonian k ⋅ p model, a large valley polarization of 8.7 meV is observed, which is mainly contributed by the SOC effect and not magnetic exchange field. Meanwhile, the magneto-crystal anisotropy of VI3 layer is also obviously altered from the [100] to [001] magnetic axis compared to the isolated VI3 monolayer. The reduction in the interlayer space strengths the W–V atomic coupling, resulting in a significant increase in the spin and valley polarization. Compression strain shows weakening effect on the valley polarization, while the tensile strain largely enhances the valley polarization of VI3/WSe2 heterostructure, which can reach the maximum value of 29.1 meV at the tensile strain of 8%. The V spin direction (θ) has significant effect on valley polarization of WSe2 layer, which is positively correlated with the magnetization strength of V atom in the vertical direction. Furthermore, constructing the VI3/WSe2/VI3 sandwich heterostructure can induce a larger valley polarization, which can reach a maximum value of 32.4 meV. These results indicate that the VI3/WSe2 heterostructure is a potential candidate for valleytronics. [ABSTRACT FROM AUTHOR]

Piezoelectricity is a well-known effect in a vast number of technologically important insulators and semiconductors and exists in 20 out of the 32 three-dimensional crystal classes. The piezoelectric effect is the driving mechanism behind several classical sensors and transmitters, and also most recently, in many nanodevices. Zhong Lin Wang coined the fields piezotronics and piezo-phototronics where the piezoelectric effect plays a dominant role. Piezoelectricity couples in a linear fashion mechanical strain to electrical fields and vice versa. In solids, there is another linear coupling between strain and the electric potential, known as the deformation potential effect. While linear in its coupling nature, this effect does not require the solid to be non-centrosymmetric in contrast to the piezoelectric effect. Moreover, the deformation potential effect is quantitatively huge and leads to changes in the conduction and valence band edges of III–V and II–VI materials of, typically, 50–100 meV in the presence of 1 % strain. Therefore, the deformation potential effect is essential to determine the electronic and photonic properties of bulk and nanostructure semiconductors in the presence of strain. In this work, we compute the relative importance of piezoelectricity and the deformation potential effect in the presence of lattice mismatch and external strain. We choose p − n junctions of ZnO/GaN structures but anticipate that the general conclusions can be carried over to other material structures. The main result of the present work is that both the inclusion of the deformation potential effect and piezoelectricity is crucial to correctly compute the effect of strain on p − n junction current–voltage curves and photonic properties. In our analysis of wurtzite heterostructures, the spontaneous polarization effect is also included but this effect appears to play a minor role for electronic and photonic properties. [ABSTRACT FROM AUTHOR]

In this work, (1− x)Bi 0 · 5 (Na 0 · 8 K 0.2) 0.5 TiO 3 - x SrTiO 3 ceramics were synthesized by the solid-phase method. The SrTiO 3 dopants cause a phase transition from of rhombohedral to tetragonal resulting in an enhanced strain of 0.49 % and normalized strain d 33 * of 817 p.m./V under 60 kV/cm at a doping amount of 0.04. The microstructure of BNKT-0.04ST, including cation displacements δ Ti-Bi/Na and the tilt of oxygen octahedron are researched by aberration corrected scanning transmission electron microscope (AC-STEM). The fast Fourier transform (FFT) of the annular dark field (ADF) STEM pattern along [110] axis reveals the 1/2 (ooo) superlattice reflection spots due to anti-phase a − a − a − the tilt of oxygen octahedron. The cation displacement vector maps based on the ADF STEM and the enhanced annular bright fielde (eABF) STEM images along the [100] axis show the rhombohedral and tetragonal phase nanodomains, and the displacement decreases gradually from the inside of the nanodomains towards the domain walls. The tilt of oxygen octahedron has the same variation tendency indicating the regional coherence. Due to the flexible nanodomains based on the cooperative effect of the tilt of oxygen octahedron and cation displacement, which is thought to be the origin of the relaxor characteristic and strain. [ABSTRACT FROM AUTHOR]

The direct anterior approach (DAA) and posterior approach (PA) for total hip arthroplasty (THA) have advantages and disadvantages, but their physiologic burden to the surgeon has not been quantified. This study was conducted to determine whether differences exist in surgeon physiological stress and strain during DAA in comparison to PA. We evaluated a prospective cohort of 144 consecutive cases (67 DAA and 77 PA). There were 5, high-volume, fellowship-trained arthroplasty surgeons who wore a smart-vest that recorded cardiorespiratory data while performing primary THA DAA or PA. Heart rate (beats/minute), stress index (correlates with sympathetic activations), respiratory rate (respirations/minute), minute ventilation (L/min), and energy expenditure (calories) were recorded, along with patient body mass index and operative time. Continuous data was compared using t -tests or Mann Whitney U tests, and categorical data was compared with Chi -square or Fischer's exact tests. There were no differences in patient characteristics. Compared to PA, performing THA via DAA had a significantly higher surgeon stress index (17.4 versus 12.4; P <.001), heart rate (101 versus 98.3; P =.007), minute ventilation (21.7 versus 18.7; P <.001), and energy expenditure per hour (349 versus 295; P <.001). However, DAA had a significantly shorter operative time (71.4 versus 82.1; P =.001). Surgeons experience significantly higher physiological stress and strain when performing DAA compared to PA for primary THA. This study provides objective data on energy expenditure that can be factored into choice of approach, case order, and scheduling preferences, and provides insight into the work done by the surgeon. [ABSTRACT FROM AUTHOR]

Introduction: Suture tensile properties have only been tested in extrauterine environments. Amniotic fluid (AF) is a complex milieu of enzymes and inflammatory factors. This study tested the mechanical properties of sutures with a variety of inherent properties, after exposure to AF from patients with conditions prompting fetal intervention. Methods: AF was obtained from 3 patients with twin-twin transfusion syndrome (TTTS), and 3 patients with neural tube defects. Six types of 2-0 sutures were placed on 1.2 N of tension to mimic placement in vivo, and incubated in AF at 37°C (98.6°F). These included ethylene terephthalate (Ethibond), glycomer 631 (V-Loc), poliglecaprone 25 (Monocryl), poly-4-hydroxybutyrate (Monomax), polydioxanone (PDS), and polyglactin 910 (Vicryl). Failure load, stress, strain, and initial modulus were tested after 24 h of incubation and after 4 weeks, and compared with control (unincubated) sutures using t tests, Kruskal-Wallis tests, and stress-strain curves. Results: Poliglecaprone 25 and polyglactin 910 dissolve more quickly in AF compared to outside the uterus, disintegrating at 4 weeks. Ethylene terephthalate and PDS experienced little change across 4 weeks of incubation. Glycomer 631 and poly-4-hydroxybutyrate exhibited interesting behavior in AF: glycomer 631 became more deformable at 24 h but later regained toughness by 4 weeks, while poly-4-hydroxybutyrate became tougher and in some cases stronger with time in AF. As a class, braided sutures act more like rigid materials, and monofilaments act like deformable plastics. Conclusion: These findings along with other suture characteristics such as ease of handling and availability may inform fetal intervention teams as they optimize procedures in a relatively new surgical field. [ABSTRACT FROM AUTHOR]

Metal halide perovskite photovoltaics have emerged as a high efficiency, low‐cost alternative that can potentially rival or enhance conventional silicon technology. Despite exceptional initial power conversion efficiencies, achieving compliance with international standards and widespread adoption requires further enhancements to their operational stability. Notably, addressing mechanical strain and stress in brittle perovskites has emerged as a pivotal approach to mitigate chemical degradation and improve reliability during thermal cycling. In this study, a popularized strain engineering strategy is investigated in which a high coefficient of thermal expansion (CTE) hole transport layer (i.e., PDCBT) is cast onto inorganic perovskite (CsPbI2Br) at 100 °C. Contrary to previously published results, the X‐ray diffraction (XRD):Sin2ψ and substrate curvature measurement techniques show that the hole transport layer has no discernible impact on perovskite strain. The accuracy of the XRD:Sin2ψ method for measuring strain is highlighted in contrast to an analysis based on shifts of single XRD peaks which can be influenced by multiple artifacts. The findings in this study are in accordance with mechanics theory: thin layers are unable to induce significant strain changes in perovskite thin films as the force they apply is negligible compared to that applied by a thick and stiff substrate. [ABSTRACT FROM AUTHOR]

Objective: To analyze the function of the left heart in patients with different courses of gout, the independent influencing factors for left heart functional changes, and interactions between left atrial and left ventricular functions. Methods: Patients with gout (n = 171) were selected; 87 patients with a disease course <10 years were included in Group I, and 84 patients with a disease course ≥10 years were included in Group II. Ninety‐four healthy volunteers comprised the control group. Results: The intergroup differences in cardiac strain parameters were statistically significant (p <.05). Moreover, the differences gradually declined with disease progression. Multivariate logistic regression analysis showed that uric acid was an independent predictor of decreased left ventricular global longitudinal strain (LVGLS). Moreover, LVGLS had a positive effect on the left atrial systolic rate (LASr) and the left atrial systolic contraction time (LASct) but no interaction with the left atrial systolic contraction duration (LAScd). Conclusion: The course of the disease significantly affected the function of the left heart in gout patients, and uric acid was observed to be an independent predictor of decreased LVGLS in gout patients. [ABSTRACT FROM AUTHOR]

Context and results: The structure, electronic and optical properties of single-layer transition metallic chalcogenides ZrX3 (X = S, Se, Te) have been studied by density functional theory. The electron energy dispersion curve shows that ZrX3 has semiconductor properties, in which the conduction band is mainly contributed by the correlated states of the Zr-d orbital, and the valence band is mainly contributed by the correlated states of the X-p orbital. It is found that b-axis and biaxial strain have great influence on the bandgap and the shift of density of states is also large. At the same time, the peak value of density of states increases greatly when biaxial strain is applied. It is of guiding significance for selecting suitable substrates to prepare two-dimensional ZrX3 materials to study their electronic properties. The calculation of optical constants confirms that ZrX3 has strong optical anisotropy. In the visible range, the light absorption efficiency of ZrX3 in the direction of electric field polarization [100] is higher than that in the direction of [010]. The reflectance spectral results show that ZrS3 and ZrSe3 in the [100] directions have the highest reflectance, and ZrTe3 in the [010] direction has the highest reflectance, even in the long electromagnetic radiation range (up to 10 eV), which is of great significance for the construction of visible optical devices. Computational method: All computations have been carried out based on density functional theory (DFT) as implemented in the CASTEP code. The pseudo-potential is adopted by the norm conserving, and the exchange correlation functional is adopted by the Perdew-Burke-Ernzerhof in local generalized gradient approximation (GGA). [ABSTRACT FROM AUTHOR]

This paper presents a recent investigation into the electromechanical behavior of thermally reduced graphene oxide (rGO) as a strain sensor undergoing repeated large mechanical strains up to 20.72%, with electrical signal output measurement in multiple directions relative to the applied strain. Strain is one the most basic and most common stimuli sensed. rGO can be synthesized from abundant materials, can survive exposure to large strains (up to 20.72%), can be synthesized directly on structures with relative ease, and provides high sensitivity, with gauge factors up to 200 regularly reported. In this investigation, a suspension of graphene oxide flakes was deposited onto Polydimethylsiloxane (PDMS) substrates and thermally reduced to create macroscopic rGO-strain sensors. Electrical resistance parallel to the direction of applied tension ( x ^ ) demonstrated linear behavior (similar to the piezoresistive behavior of solid materials under strain) up to strains around 7.5%, beyond which nonlinear resistive behavior (similar to percolative electrical behavior) was observed. Cyclic tensile testing results suggested that some residual micro-cracks remained in place after relaxation from the first cycle of tensile loading. A linear fit across the range of strains investigated produced a gauge factor of 91.50(Ω/Ω)/(m/m), though it was observed that the behavior at high strains was clearly nonlinear. Hysteresis testing showed high consistency in the electromechanical response of the sensor between loading and unloading within cycles as well as increased consistency in the pattern of the response between different cycles starting from cycle 2. [ABSTRACT FROM AUTHOR]

For semiconducting two-dimensional transition metal dichalcogenides (TMDs), the carrier transport properties of the material are affected by strain engineering. In this study, we investigate the carrier mobility of monolayer hafnium disulphide (HfS2) under different biaxial strains by first-principles calculations combined with the Kubo–Greenwood mobility approach and the compact band model. The decrease/increase in the effective mass of the conduction band (CB) of monolayer HfS2 caused by biaxial tensile/compressive strain is the major reason for the enhancement/degradation of its electron mobility. The lower hole effective mass of the valence bands (VB) in monolayer HfS2 under biaxial compressive strain improves its hole transport performance compared to that under biaxial tensile strain. In summary, biaxial compressive strain causes a decrease in both the effective mass and phonon scattering rate of monolayer HfS2, resulting in an increase in its carrier mobility. Under the biaxial compressive strain reaches 4%, the electron mobility enhancement ratio of the CB of monolayer HfS2 is ~90%. For the VB of monolayer HfS2, the maximum hole mobility enhancement ratio appears to be ~13% at a biaxial compressive strain of 4%. Our results indicate that the carrier transport performance of monolayer HfS2 can be greatly improved by strain engineering. [ABSTRACT FROM AUTHOR]

The muscle tendon junction (MTJ) transmits the force generated by the muscle to the tendon and ultimately to the bone. Tears and strains commonly occur at the MTJ where regeneration is limited due poor vascularisation and the complexity of the tissue. Currently treatments for a complete MTJ tear are often unsuccessful. The creation of a tissue engineered MTJ would therefore be beneficial in the development of a novel treatment. In this study, aligned electrospun polycaprolactone fibres were fabricated and human myoblasts and tenocytes were cultured on the scaffold. The effect of 10 % cyclic strain and co-culture of myoblasts and tenocytes on the MTJ formation was investigated. The application of strain significantly increased cell elongation, and MTJ marker gene expression. Co-culture of myoblasts and tenocytes with strain induced higher MTJ marker gene expression compared with myoblasts and tenocytes cultured separately. Paxillin and collagen 22, naturally found in the MTJ, were also produced when cells were combined and grown in a 10 % strain environment. For the first time these results showed that the combination of the strain and co-culture of myoblasts and tenocytes promotes gene expression and production of proteins that are found in the MTJ. [ABSTRACT FROM AUTHOR]

A comprehensive theoretical study has been carried out to examine the electronic and thermoelectric properties of As X Y (where X = S , Se; Y = Cl , Br, and I) monolayers. The lattice constants of these monolayers are optimized to determine their most stable configurations. The electronic and thermoelectric characteristics of these monolayers are calculated using state-of-the-art computational methods. Specifically, the first-principles calculations in combination with semiclassical Boltzmann transport theory were employed to gain insights into their behavior. One of the crucial findings of the study is the observation of an indirect band nature in all the studied monolayers. This characteristic provides valuable information about the materials' electronic behavior and potential applications. Furthermore, the impacts of tensile and compressive strains on these monolayers are investigated. Interestingly, we observed changes in the band value when strain is applied, which opens up exciting possibilities for engineering their electronic properties. Importantly, despite these changes, the band nature of the monolayers remains consistent. In particular, it is found that the AsSI monolayer exhibits a remarkable enhancement in the Seebeck coefficient, both in the unstrained state and under a compressive strain of 4% in the p-type region. This enhancement leads to a higher power factor (PF), suggesting that AsSI monolayers could be promising candidates for efficient thermoelectric devices. Overall, these findings highlight the potential of strain engineering to tailor the electronic properties of As X Y monolayers, offering exciting opportunities for their application in thermoelectric devices. This research contributes valuable insights into the design and optimization of novel materials for future energy conversion and electronic applications. [ABSTRACT FROM AUTHOR]

Background: Despite Puerto Ricans having one of the highest rates of substance use among Hispanic groups in the United States, limited research has focused on the impact of perceived discrimination and stress on substance use among older adults. Individuals who experience stressful events are inclined to engage in harmful behaviors as a coping mechanism. Objectives: Based on the propositions of the General Strain Theory, the current study explores the relationship between perceived discrimination, perceived stress, social activities, and the use of alcohol and cigarettes. Methods: Baseline data from the Boston Puerto Rican Health Study collected in 2014 was used to conduct a logistic regression analysis. Results: The findings reveal that while perceived discrimination is significantly linked to both types of substance use, social activities may serve as a protective factor for cigarette use. Conclusion/Importance: Our study findings emphasize the need to examine perceived discrimination as a stressor impacting the health and well-being of Puerto Ricans in later adulthood. Policy implications for reducing substance use and directions for future research are discussed [ABSTRACT FROM AUTHOR]

The complications arising after the transplantation of conventional stents put atherosclerotic cardiovascular patients at high risk. Biodegradable poly-lactic acid (PLA) stents provide practical solutions for diseased vessels (atherosclerotic) and avoid the side complications of vessels and their incompatibility with permanent stents in the long term. PLA is a biodegradable and reliable material that is used for biodegradable stents designs to maintain natural mechanical behaviour in blood vessels. In this study, we suggest a new cross section 'circular and elliptic' that are proposed based on basic square shape cross section to study the mechanical behaviour of stents under pulsatile blood pressure in the blood vessels in order to choose the best shape to allow the biodegradability of Absorb stents with Poly-lactic Acid (PLA) material by numerical fatigue study. Three types of cross-sections stents struts have been analysed to compare their mechanical properties in terms of stress, strain, fatigue damage and life cycle. The numerical results obtained from the finite element analysis (FEA) method demonstrate that the elliptical and circular stents design has better efficiency in terms of stress and strain (16.66–33.33%) and fatigue damage (62.4–86.07%) compared to the square design. [ABSTRACT FROM AUTHOR]

Objective: Our study aimed to explore with cardiovascular magnetic resonance (CMR) the impact of left atrial (LA) and left ventricular (LV) myocardial strain in patients with acute pericarditis and to investigate their possible prognostic significance in adverse outcomes. Method: This retrospective study performed CMR scans in 36 consecutive patients with acute pericarditis (24 males, age 52 [23–52]). The primary endpoint was the combination of recurrent pericarditis, constrictive pericarditis, and surgery for pericardial diseases defined as pericardial events. Atrial and ventricular strain function were performed on conventional cine SSFP sequences. Results: After a median follow-up time of 16 months (interquartile range [13–24]), 12 patients with acute pericarditis reached the primary endpoint. In multivariable Cox regression analysis, LA reservoir and LA conduit strain parameters were all independent determinants of adverse pericardial diseases. Conversely, LV myocardial strain parameters did not remain an independent predictor of outcome. With receiving operating characteristics curve analysis, LA conduit and reservoir strain showed excellent predictive performance (area under the curve of 0.914 and 0.895, respectively) for outcome prediction at 12 months. Conclusion: LA reservoir and conduit mechanisms on CMR are independently associated with a higher risk of adverse pericardial events. Including atrial strain parameters in the management of acute pericarditis may improve risk stratification. Clinical relevance statement: Atrial strain could be a suitable non-invasive and non-contrast cardiovascular magnetic resonance parameter for predicting adverse pericardial complications in patients with acute pericarditis. Key Points: • Myocardial strain is a well-validated CMR parameter for risk stratification in cardiovascular diseases. • LA reservoir and conduit functions are significantly associated with adverse pericardial events. • Atrial strain may serve as an additional non-contrast CMR parameter for stratifying patients with acute pericarditis. [ABSTRACT FROM AUTHOR]

The development of various machines and equipment containing parts or assemblies made of hyperelastic materials (e.g., rubber, silicone) is difficult because of the intricacies involved in the description of their mechanical properties. This is especially seen in calculations using simulation modeling. The behavior of hyperelastic materials is described by utilizing the results of research conducted with specialized equipment. This allows for the most accurate determination of their mechanical properties. Hyperelastic materials are widely used across diverse industries, encompassing mechanical engineering, the chemical and petrochemical sectors, cement production, and beyond. To determine the mechanical characteristics of SKR-788 silicone, batches of test samples were prepared, varying solely in the ratio of the base to the catalyst. Laboratory testing of silicone samples was performed on an Instron 4500 device, and data such as loads, displacements, and deformations were obtained. In order to verify the results of the tests against the results of simulation modeling in Ansys software, a model of the experimental sample was built. The obtained results of uniaxial tensile testing of the experimental sample were taken into account during the description of the material in the Mooney-Rivlin model. The calculation scheme for the test sample during simulation modeling is similar to the one used during its laboratory testing. Applying the load to the test sample during the simulation proceeded incrementally based on time. As a result of the work, the constants of the SKR-788 silicone material for the three-parameter Mooney-Rivlin model were defined (C10 = -0.10335 MPa, C01 = 0.57534 MPa, and C11 = 0.093309 MPa). As a result of simulation modeling of the experimental silicone sample, the values of its displacements and stresses were obtained. Upon comparing the stress values derived from the results of laboratory testing on the Instron 4500 equipment with those obtained from simulation modeling, a discrepancy of up to 7% was identified. For the first time, the characteristics of the SKR-788 silicone material have been established and verified. This will facilitate the design and research of various equipment and machine components made from hyperelastic materials. [ABSTRACT FROM AUTHOR]

Athlete's heart (AH) represents the heart's remarkable ability to adapt structurally and functionally to prolonged and intensive athletic training. Characterized by increased left ventricular (LV) wall thickness, enlarged cardiac chambers, and augmented cardiac mass, AH typically maintains or enhances systolic and diastolic functions. Despite the positive health implications, these adaptations can obscure the difference between benign physiological changes and early manifestations of cardiac pathologies such as dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), and arrhythmogenic cardiomyopathy (ACM). This article reviews the imaging characteristics of AH across various modalities, emphasizing echocardiography, cardiac magnetic resonance (CMR), and cardiac computed tomography as primary tools for evaluating cardiac function and distinguishing physiological adaptations from pathological conditions. The findings highlight the need for precise diagnostic criteria and advanced imaging techniques to ensure accurate differentiation, preventing misdiagnosis and its associated risks, such as sudden cardiac death (SCD). Understanding these adaptations and employing the appropriate imaging methods are crucial for athletes' effective management and health optimization. [ABSTRACT FROM AUTHOR]

This study addresses the limitation of traditional non-destructive testing methods in real-time corrosion monitoring of pipe elbows by proposing the utilization of fiber Bragg grating (FBG) strain sensors, renowned for their resilience in harsh environments. However, the current mathematical relationship model for strain representation of elbow corrosion is still lacking. This paper develops a finite element model to scrutinize the strain changes in the elbow due to corrosion under hydrostatic pressure and bending loads. To mitigate temperature loading effects, the corrosion degree is evaluated through the disparity between hoop and axial strains. Simulation outcomes reveal that, under hydrostatic pressure, the strain difference exhibits minimal changes with the increase in corrosion degree, while under bending moment loading, the strain difference escalates proportionally with corrosion progression. Consequently, strain induced by bending moment loading solely characterizes the corrosion degree. Moreover, the optimal placement for FBG sensors is identified at the extrados of the pipe elbow, where strain is most prominent. These insights enhance comprehension of strain–corrosion dynamics in pipe elbows, offering valuable guidance for developing an FBG-based monitoring system for real-time corrosion tracking and predictive maintenance of pipeline infrastructures. [ABSTRACT FROM AUTHOR]

Copyright of Veterinarska Stanica is the property of Croatian Veterinary Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and Aim: The structure and function of the left heart cavity have important prognostic value in heart diseases, and heart rate (HR) control is an important treatment goal. In this study, we investigated the effects of HR on left heart structure and function in hypertensive patients with normal left ventricular (LV) systolic function. Materials and Methods: This was a single-center, prospective, observational (case-control) study. A total of 153 patients were included in the study. Patients were divided into two groups according to their HR (70 beats/min and below and above 70 beats/min). LV and atrial strain analyses were performed during echocardiographic evaluation. Results: Patients with a resting HR of 70 beats/min or less were included in group 1 (64.2±4.5) and patients with a resting HR above 70 beats/min were included in group 2 (79.1±6.8). There is a significant difference between group 1 and group 2 in left atrial maximum volume (60.8±15.5 mL vs. 52.9±16.3 mL P = 0.007), left atrial minimum volume (28.8±9.5 vs. 22.6±7.9 P < 0.001), left atrial emptying fraction (52.8±8.5% vs. 56.1±8.5% P = 0.035), left atrial expansion index (1.19±0.44 vs. 1.36±0.47 P = 0.044), pLASRcd (-1.3±0.38 vs. -1.5±0.61 P = 0.031), and global longitudinal strain (-19.3±3 vs. -18.2±2.7 P = 0.07). In the multivariable regression analysis, beta-bloker [odds ratio (OR): 0.291, 95% confidence interval (CI) 0.105-0.810, P = 0.018], mean high diastolic blood pressure (OR: 1.054, 95% CI 1.009-1.101, P = 0.018), left atrial minimum volume (OR: 0.870, 95% Cl 0.809-0.938, P < 0.001), S' (OR: 10.6, 95% CI 1.1-104, P = 0.041), left atrial expansion index (OR: 0.870, 95% CI 0.809-0.930, P < 0.033) were determined as independent predictors of high resting HR. Conclusion: HR control is an important goal in patients with hypertension who have preserved LV systolic function. Mortality and morbidity can also be improved by HR control. [ABSTRACT FROM AUTHOR]

Wood drying is often accompanied by changes in mechanical properties due to external thermal energy. This study examined the influences of drying temperature on the mechanical properties of Japanese cedar based on the partial compression properties and bending properties. Two types of longitudinal specimens with quarter grain on both lateral surfaces were prepared under green conditions, followed by subsequent drying under each drying temperature (20 °C, 40 °C, 60 °C, 80 °C, and 100 °C). Then, the partial compression and bending tests were performed using the respective specimens. Young's modulus perpendicular to grain, yield stress, and compressive strength obtained by the partial compressive test were highest for wood dried at 20 °C. It was considered that the decrease in mechanical properties was attributed to the thermal influences during drying at 100 °C and other factors such as compressive residual stress and cell walls collapsing at lower temperatures. The strain energy suggested that the effects of drying temperature became apparent, especially in the plastic region during loading in the direction perpendicular to the wood fiber. Bending properties showed little influence on drying temperatures compared to the partial compressive properties, whereas the fractures found under the loading point of the wood dried at 100 °C suggested a reduction in resistance to shear forces. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Technologies / Materiali in Tehnologije is the property of Institute of Metals & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although polystyrene materials with added graphite are actively used for the thermal insulation of buildings, there are serious problems with the detachment and warping of these materials under the influence of solar radiation. However, no systematic studies have yet been carried out on the aging of polystyrene under exposure to solar radiation. The article presents research aimed at determining changes in the thermal conductivity, compressive stress, tensile strength, and water absorption of expanded polystyrene with the addition of graphite, exposed to direct solar radiation under in situ conditions. For this purpose, expanded polystyrene (EPS) with the addition of graphite (gray EPS) and expanded polystyrene made of composite panels (gray EPS and white EPS) were exposed to direct solar radiation under in situ conditions. A third sample (reference), which was entirely white polystyrene (without the addition of graphite), was included in the tests. The results showed that expanded polystyrene with the addition of graphite degraded under the influence of direct solar radiation but improved its strength properties. Expanded polystyrene made of composite improved its compressive strength properties by nearly 11 kPa (18%), and expanded polystyrene with the addition of graphite improved its compressive strength properties by 0.4 kPa (0.5%). And the tensile strength for composite-made expanded polystyrene increased by 7 kPa (9%), and that for expanded polystyrene with the addition of graphite increased by 26 kPa (37%). At the same time, water absorption for expanded polystyrene made of composite also increased by 0.06 kg/m2 (60%), and that for expanded polystyrene with the addition of graphite increased by 0.04 kg/m2 (44%). [ABSTRACT FROM AUTHOR]

This study examines the impact of the COVID-19 pandemic on fraud victimization in Hong Kong, providing valuable insights beyond the Western context. Drawing on general strain theory and routine activity theory, this research explores the influence of economic recession at the local and adjacent societal levels, as well as residential duration (refers to relative time spent at residences), on fraud victimization in Hong Kong. Utilizing 10 years (120 months) of monthly police-recorded victimization data, this study employs various methodologies, including ARIMA forecasting, single-group interrupted time series analysis (ITSA), and Poisson regression, to explore the impact of the COVID-19 pandemic on fraud victimization in Hong Kong. The ARIMA framework reveals an unexpected and significant increase in fraud victimization during the COVID-19 period, surpassing the predicted levels. The ITSA results demonstrate that the pandemic had a short-term and long-term effect on fraud victimization in Hong Kong. To further understand the factors contributing to this change, a Poisson regression analysis is conducted. The findings highlight the positive and significant impact of residential duration and the unemployment rate in mainland China on fraud victimization, aligning with the propositions of routine activity theory and general strain theory. Limitations and policy implications at both the local and international levels are discussed. [ABSTRACT FROM AUTHOR]

The goal of this study was to determine the potential for right ventricular (RV) and left ventricular (LV) strain to predict cardiopulmonary complications of COVID-19. We identified 276 patients with COVID-19 who underwent transthoracic echocardiography within 30 days of COVID-19 diagnosis at our institution. Patients were excluded if they had a history of any primary outcomes before COVID-19 diagnosis or insufficient imaging. LV global longitudinal strain (GLS) and RV GLS were obtained using 2-dimensional speckle-tracking echocardiography. Primary outcomes were death, pulmonary embolism, congestive heart failure (CHF), cardiomyopathy, pulmonary fibrosis, pulmonary hypertension, acute respiratory distress syndrome (ARDS), and myocardial infarction (MI) occurring after COVID-19 diagnosis. In the final analysis of 163 patients, mean RV GLS and LV GLS were reduced, and 43.6% developed at least one primary outcome. There were significant differences in LV GLS distribution in terms of CHF, cardiomyopathy, and MI in bivariate analysis. However, LV GLS was not significantly associated with CHF after adjusting for LV ejection fraction and RV fractional area change, nor with MI after adjusting for troponin T. RV GLS was significantly associated with ARDS after adjusting for other variables. In the risk stratification of patients with COVID-19, strain imaging can provide incremental prognostic information, as worsened RV GLS is associated with the development of ARDS. [ABSTRACT FROM AUTHOR]

Abstract Cardiovascular complications are common in patients with severe liver disease and are an important cause of peri-operative and post-transplant morbidity and mortality. Cirrhotic cardiomyopathy (CCM), often found in advanced liver disease, is characterized by diastolic dysfunction, systolic dysfunction, and electrophysiological abnormalities. While CCM may not cause symptoms at rest, it can become evident during stressful activities, such as surgery. Liver transplantation, while being the definitive treatment for end-stage liver disease (ESLD), carries significant cardiovascular risks. Preoperative cardiac evaluation is essential for assessing these risks and planning appropriate management. Cardiac imaging, particularly echocardiography, plays a crucial role in evaluating liver transplant candidates, helping to identify conditions such as CCM, pulmonary hypertension, hepatopulmonary syndrome, and others. Currently, liver transplant anesthetists must acquire echocardiographic knowledge and skills to evaluate the cardiocirculatory conditions of the transplanted patient, especially in the pre-operative phase, but also intra-operatively and post-operatively.

Nanolayered Zr/Nb metals are considered promising for advanced nuclear reactors due to their superior resistance to irradiation. In this study, Zr/Nb multilayers were irradiated with 50 keV He+ ions to a fluence of 1 × 1017 ions/cm2 at temperatures of room temperature, 350 °C, and 500 °C to investigate irradiation-induced structural changes. X-ray diffraction (XRD) analysis indicated low-angle shifts of 0.08–0.54° and high-angle shifts of 0.08–0.42° in the irradiated Zr and Nb layers, suggesting tensile and compressive strains, respectively. At 500 °C, the selected-area electron diffraction (SAED) observed a 9.2% lattice expansion in Zr and a 0.13% contraction in Nb. Geometric phase analysis (GPA) revealed varying strain distributions, transitioning from incoherent to coherent interfaces with increasing irradiation damage. Transmission electron microscopy (TEM) identified the presence of He bubbles in the Zr layer as one of the reasons for strain differences. Nanoindentation tests showed an increase at a depth of 150 nm hardness of 0.831 GPa at 500 °C compared to 350 °C. These results are attributed to differences in crystal structure, vacancy dynamics, interfacial effects, and lattice strain influences. Stability of Zr/Nb interfaces after He irradiation was studied. This study provides insights into the radiation behavior of Zr/Nb nanoscale metallic materials, enhancing our understanding of their potential as structural materials in nuclear energy systems.

Abstract Establishing normal values of left atrial (LA) phasic strains and strain rates is essential for distinguishing between normal and abnormal functions, determining the degree of abnormality, and understanding the clinical significance of reported values in pediatrics. This meta-analysis aimed to establish normal values of two-dimensional speckle-tracking echocardiography (2DSTE)-derived LA phasic strains and strain rates in the pediatric population and identify the sources of inter-study heterogeneity for these values. A comprehensive search of PubMed, Scopus, and Embase databases was conducted using keywords such as “left atrial/left atrium,” “strain/speckle/deformation,” and “echocardiography” combined with pediatric age categories. Inclusion criteria comprised English-language human studies involving healthy subjects under 18 years of age. Subjects were categorized as neonates (up to 1 month), infants (1–12 months), and children (1–18 years). A random-effects model was applied to determine 2DSTE-derived LA strains and strain rates, and a meta-regression analysis was performed to investigate inter-study heterogeneity. Our analysis included 17 studies involving 1448 healthy subjects. For children, the mean values of LA strains during the reservoir, conduit, and contraction phases were 47.3% (95% CI 42.5–52.1%), 32.8% (95% CI 27.8–37.8%), and 12% (95% CI 10.0–14.1%), respectively. The mean values for LA strain rates were 2.4 s−1 (95% CI 1.1–3.8 s−1), 4.3 s−1 (95% CI 0.6–8.0 s−1), and 2.4 s−1 (95% CI 0.4–4.5 s−1), respectively. Inter-study heterogeneity for 2DSTE-derived LA phasic strains and strain rates was attributed to factors such as the number of study participants, publication year, software utilized, gating methods, the number of analyzed segments, the geographical region of the study, and heart rate. This study established the normal range of 2DSTE-derived LA phasic strains and strain rates. Additionally, inter-study heterogeneity was found to be influenced by various demographic, physiologic, and methodological factors.

Abstract Aims The COVID‐19 infection has been described as affecting myocardial injury. However, the relation between left ventricular global longitudinal strain (GLS), global circumferential strain (GCS) and global radial strain (GRS), disease severity and all‐cause mortality in COVID‐19 is unclear. Methods and Results The study consisted of 220 patients with COVID‐19, including 127 (57.5%) with mild, 43 (19.5%) with moderate and 50 (22.7%) with severe/critical conditions. Myocardial dysfunction was analysed by GLS, GCS and GRS using two‐dimensional speckle‐tracking echocardiography. Hazard ratios and Kaplan–Meier curves were produced to assess the association between strains and cardiac biomarker indices with a composite outcome of all‐cause mortality. With an average follow‐up period of 11 days, 19 patients reached the endpoint (death). Significant associations were found for the three strain parameters and the levels of blood urea nitrogen (BUN) (r = 0.206, 0.221 and 0.355, respectively). Cardiac troponin I (cTnI) was closely related to the GLS and GCS (r = 0.240 and 0.324, respectively). In multivariable Cox regression, GCS > −21.6% was associated with all‐cause death {hazard ratio, 4.007 [95% confidence interval (CI), 11.347–11.919]}. Conclusions GLS, GCS and GRS are significantly related to myocardial dysfunction in patients with COVID‐19. Worsening GCS poses an increased risk of death in COVID‐19.

Pb(Zr,Ti)O3-based ceramics are the mainstream materials for commercial multilayer piezoelectric ceramic actuators, but to date, large strains at low electric fields have not been well solved. Herein, 0.95Pb(Zr0.56Ti0.44)O3–0.05(Bi0.5Na0.5)TiO3–xBaZrO3 (PZT–BNT–xBZ) ceramics with efficient ferroelectric domain wall motion were designed and realized by reducing lattice distortion and changing the domain structure. It is found that the introduction of BaZrO3 (BZ) weakens the tetragonal phase distortion of PZT, contributing to a reduction in the mechanical stress that impedes the migration of domain walls. Moreover, the domain structures could be modified by adjusting the BZ content, where short and broad striped domains are constructed with high amplitude characteristics to enhance the domain wall motion. A large strain of 0.39% is accordingly achieved at an electric field as low as 40 kV/cm for the sample with x = 0.03, accompanied by excellent temperature stability over the temperature range of 30–210 °C. This study delves into the synergistic effects of reducing lattice distortion and changing domain structure on domain wall motion and provides an effective strategy to improve the strain of PZT-based piezoelectric ceramics.

For some decades now, Lactic acid bacteria (LAB) have been an important raw resource in the food and pharmaceutical industries to produce variety of dairy based products including but not limited to cheese, yoghurt, lactic acid. drugs and cosmetics. The LAB strains include the genera of Lactobacillus and Streptococcus. The importation of raw materials such as lactic acid, which can be obtained from indigenous sources, however, affects the foreign exchange of Nigeria's economy greatly. This study was designed to screen, characterize and identify LAB for industrial applications. A total of eighty (80) Lactic Acid Bacteria (LAB) strains were isolated from samples of nunu (a locally fermented milk product) using basic microbiological procedures such as morphological/phenotypic, gram staining, and other biochemical tests. All the isolates were tested for their acidification, curd formation and aroma production abilities. After forty-eight (48) hours of incubation at 420C, twenty-three (23) isolates which satisfied established phenotypic and biochemical criteria were selected for further functional tests. Out of the twenty-three (23) isolates obtained, two (2) strains L53 and L12 had additionally high exopolysaccharide production ability and correspondingly produced yoghurt with high viscosity and very low residual content. Based on the remarkable characteristics obtained from these two species, they are therefore recommended for optimization and proposed for large scale utilization as starter cultures in the dairy industries.

Background and Aim: The structure and function of the left heart cavity have important prognostic value in heart diseases, and heart rate (HR) control is an important treatment goal. In this study, we investigated the effects of HR on left heart structure and function in hypertensive patients with normal left ventricular (LV) systolic function. Materials and Methods: This was a single-center, prospective, observational (case-control) study. A total of 153 patients were included in the study. Patients were divided into two groups according to their HR (70 beats/min and below and above 70 beats/min). LV and atrial strain analyses were performed during echocardiographic evaluation. Results: Patients with a resting HR of 70 beats/min or less were included in group 1 (64.2±4.5) and patients with a resting HR above 70 beats/min were included in group 2 (79.1±6.8). There is a significant difference between group 1 and group 2 in left atrial maximum volume (60.8±15.5 mL vs. 52.9±16.3 mL P = 0.007), left atrial minimum volume (28.8±9.5 vs. 22.6±7.9 P < 0.001), left atrial emptying fraction (52.8±8.5% vs. 56.1±8.5% P = 0.035), left atrial expansion index (1.19±0.44 vs. 1.36±0.47 P = 0.044), pLASRcd (-1.3±0.38 vs. -1.5±0.61 P = 0.031), and global longitudinal strain (-19.3±3 vs. -18.2±2.7 P = 0.07). In the multivariable regression analysis, beta-bloker [odds ratio (OR): 0.291, 95% confidence interval (CI) 0.105-0.810, P = 0.018], mean high diastolic blood pressure (OR: 1.054, 95% CI 1.009-1.101, P = 0.018), left atrial minimum volume (OR: 0.870, 95% Cl 0.809-0.938, P < 0.001), S’ (OR: 10.6, 95% CI 1.1-104, P = 0.041), left atrial expansion index (OR: 0.870, 95% CI 0.809-0.930, P < 0.033) were determined as independent predictors of high resting HR. Conclusion: HR control is an important goal in patients with hypertension who have preserved LV systolic function. Mortality and morbidity can also be improved by HR control.

Abstract Background A positive work environment can enhance nursing safety and patient satisfaction while alleviating nurse stress. Conversely, a poor work environment can harm nurses’ physical and mental health and compromise the quality of care, particularly in the high-intensity and shift-based setting of the ICU. Objectives Based on the Job demands-resources (JD-R) model, this study examined the effects of job demands and job resources in the work environment, as well as personal resources, on the night-shift alertness of ICU shift nurses. Methods This cross-sectional correlational exploratory study, conducted from July to September 2022, recruited 291 ICU shift nurses from a hospital in Beijing, China. The Copenhagen Psychosocial Questionnaire (COPSOQ), the Self-resilience scale, the General Self-Efficacy Scale (GSES), and the Psychomotor Vigilance Task (PVT) were used to subjectively and objectively measure the job demands, job resources, personal resources, and night-shift alertness. SPSS 26.0 and Mplus 8.3 were used to analyze the data and construct the structural equation model. Results The night-shift reaction time was 251.0 ms (Median), indicating a relatively high level of alertness. Job demands were negatively correlated with both job resources (r=-0.570, P