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Purpose: Breast cancer patients with mutations in human tumor suppressor genes BRCA1 and BRCA2 are at higher risk of cardiovascular disease (CVD) than the general population, as they are frequently exposed to cardiotoxic chemotherapy, anti-estrogen therapy, radiation, and/or oophorectomy for cancer-related treatment and prophylaxis. Animal and cell culture models suggest that BRCA mutations may play an independent role in heart failure. We sought to evaluate cardiac structure and function in female BRCA1 and BRCA2 mutation carriers with breast cancer compared to BRCA wildtype women with breast cancer. Methods: We performed a 1:2 age- and hypertension-matched retrospective cohort study comparing BRCA1 and BRCA2 mutation carriers (n = 38) versus BRCA wildtype controls (n = 76) with a new diagnosis of breast cancer. Echocardiographic data were obtained within 6 months of breast cancer diagnosis and prior to chemotherapy, anti-estrogen therapy, radiation, or oophorectomy. Left ventricular global longitudinal strain (LV-GLS), a highly sensitive marker of LV function, was measured using QLab 15 (Philips Healthcare). Results: In the total cohort of 114 patients with a new diagnosis of breast cancer, the median age was 45 ± 11 years and the prevalence of hypertension was 8%. There were no differences in traditional cardiovascular disease risk factors between cases and controls. BRCA carriers had lower LV-GLS (− 18.1% ± 4.7% vs. − 20.1% ± 3.8%, p = 0.02) and greater right atrial area (12.9 cm2 ± 2.7 cm2 vs. 11.8 cm2 ± 2.0 cm2, p = 0.04) compared to controls; however, both LV-GLS and right atrial area were within the normal range. Compared to controls, BRCA carriers had a trend toward worse LV posterior wall thickness (0.89 cm ± 0.15 cm vs. 0.83 cm ± 0.16 cm, p = 0.06) although not statistically significant. Conclusion: In women with newly diagnosed breast cancer and prior to treatment, LV-GLS was worse in BRCA1 and BRCA2 mutation carriers compared to those with BRCA wildtype. These findings suggest that BRCA mutations may be associated with subtle changes in cardiac function. Whether differences in GLS translate to increased cardiovascular risk in women with BRCA mutations needs to be further characterized. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have made significant progress in the past decade, demonstrating promising potential for next‐generation solar technology. However, the strain‐induced intrinsic instability of mixed‐halide perovskites poses a significant obstacle to their widespread commercialization. Relaxation of the perovskite lattice strain is a crucial approach for enhancing photovoltaic performance and broadening their application potential. In this study, the authors conduct an analysis of strain progression in perovskite thin films, examining its impact on the physical properties of perovskites and the performance of perovskite solar cells. Furthermore, they explore its influence on device stability from the perspectives of phase transitions, chemical decomposition, and mechanical fragility. Additionally, they provide a summary of key advancements in strain‐relaxation strategies and offer design principles and synthetic approaches to address the issue of lattice strain in perovskites. This paper is intended to lay the groundwork for the theoretical development of effective strain‐relaxation methods, moving beyond sole reliance on empirical optimization. [ABSTRACT FROM AUTHOR]

Research on the deformation characteristics and failure modes of buried pipelines under local suspension conditions caused by groundwater loss in coal mining subsidence areas is conducive to grasping the failure evolution law of pipelines and providing technical support for the precise maintenance of gathering and transportation projects and the coordinated mining of gas and coal resources. First, a test system for monitoring the deformation of pipelines under loading was designed, which mainly includes pipeline load application devices, end fixing and stress monitoring devices, pipeline end brackets, and stress–strain monitoring devices. Then, a typical geological hazard faced by oil and gas pipelines in the gas–coal overlap area—local suspension—was used as the engineering background to simulate the field conditions of a 48 mm diameter gas pipeline with a localized uniform load. At the same time, deformation, top–bottom strain, end forces, and damage patterns of the pipeline were monitored and analyzed. The results show that the strain at the top and bottom of the pipeline increased as the load increased. In this case, the top was under pressure, and the bottom was under tension, and the conditions at the top and bottom were opposite.. For the same load, the strain tended to increase gradually from the end to the middle of the pipeline, and at the top, it increased significantly more than at the bottom. The tensile force carried by the end of the pipeline increased as the applied load increased, and the two were positively correlated by a quadratic function. The overall deformation of the pipeline evolved from a flat-bottom shape to a funnel and then to a triangular shape as the uniform load increased. In addition, plastic damage occurred when the pipeline deformed into a triangular shape. The results of the investigation clarify for the first time the mathematical relationship between local loads and ultimate forces on pipelines and analyze the evolution of pipeline failure, providing a reference for pipeline field maintenance. Based on this, the maximum deformation of and the most vulnerable position in natural gas pipelines passing through a mining subsidence area can be preliminarily judged, and then the corresponding remedial and protection measures can be taken, which has a certain guiding role for the protection of natural gas pipelines. [ABSTRACT FROM AUTHOR]

Background: Owing to a lack of data, this study aimed to explore the effect of cardiac preload on myocardial strain in patients with sepsis. Methods: A total of 70 patients with sepsis in intensive care unit (ICU) of a tertiary teaching hospital in China from January 2018 to July 2019 and underwent transthoracic echocardiography were enrolled. Echocardiographic data were recorded at ICU admission and 24 h later. Patients were assigned to low left ventricular end-diastolic volume index (LVEDVI) and normal LVEDVI groups. We assessed the impact of preload on myocardial strain between the groups and analyzed the correlation of echocardiographic parameters under different preload conditions. Results: Thirty-seven patients (53%) had a low LVEDVI and 33 (47%) a normal LVEDVI. Those in the low LVEDVI group had a faster heart rate (121.7 vs. 95.3, p < 0.001) and required a greater degree of fluid infusion (3.67 L vs. 2.62 L, P = 0.019). The left ventricular global strain (LVGLS) (-8.60% vs. -10.80%, p = 0.001), left ventricular global circumferential strain (LVGCS) (-13.83% vs. -18.26%, p = 0.006), and right ventricular global longitudinal strain (RVGLS) (-6.9% vs. -10.60%, p = 0.001) showed significant improvements in the low LVEDVI group after fluid resuscitation. However, fluid resuscitation resulted in a significantly increased cardiac afterload value (1172.00 vs. 1487.00, p = 0.009) only in the normal LVEDVI group. Multivariate backward linear regression showed that LVEDVI changes were independently associated with myocardial strain-related improvements during fluid resuscitation. The baseline LVEDVI was significantly negatively correlated with the LVGLS and RVGLS (r = -0.44 and − 0.39, respectively) but not LVGCS. LVEDVI increases during fluid resuscitation were associated with improvements in the myocardial strain degree. Conclusions: Myocardial strain alterations were significantly influenced by the cardiac preload during fluid resuscitation in sepsis. [ABSTRACT FROM AUTHOR]

Mxenes has attracted wide attention due to its advantages of high conductivity, diverse composition, thinness and adjustable structure. In this paper, we systematically calculated adsorption energy, Gibbs free energy, and exchange current density of Ti 3 C 2 O 2 and Ti 4 C 3 O 2. The effect of H-coverage, element (Cr, Hf, Mo, Nb, Ta, V) doping and strain application on the HER catalytic performance were also analyzed. The results show that Ti 4 C 3 O 2 has stronger catalytic ability than Ti 3 C 2 O 2. H coverage is negatively correlated with catalytic performance of Ti n+1 C n O 2 (n = 2, 3). Among calculated doping elements, for improving catalytic ability of Ti 3 C 2 O 2 , V or Mo doping is beneficial. While for Ti 4 C 3 O 2 , only Mo doping is beneficial. Furthermore, compression strain of −5%, −3%, −1% is beneficial for improving catalytic performance of Ti 3 C 2 O 2 and Ti 4 C 3 O 2. Our work reveals the microscopic mechanism of MXene catalyzing HER, which is useful for the further development of water electrolysis catalysts. [Display omitted] • Catalytic properties of Tin+1CnO2 (n = 2, 3) were systematically calculated & compared • Ti4C3O2 shows better catalytic performance than Ti3C2O2 • H coverage is negatively correlated with catalytic performance of Tin+1CnO2 (n = 2, 3) • V, Mo for Ti3C2O2, Mo for Ti4C3O2 can improve the catalytic performance • Compression strain of -5%, -3%, -1% is beneficial for Ti3C2O2 and Ti4C3O2 catalysts [ABSTRACT FROM AUTHOR]

Background: The adverse prognostic impact of diabetes on hypertrophic cardiomyopathy (HCM) is poorly understood. We sought to explore the underlying mechanisms in terms of structural and functional remodelling in HCM patients with coexisting diabetes (HCM-DM). Methods: A total of 45 HCM-DM patients were retrospectively included. Isolated HCM controls (HCM patients without diabetes) were matched to HCM-DM patients in terms of maximal wall thickness, age, and gender distribution. Left ventricular (LV) and atrial (LA) performance were evaluated using cardiac magnetic resonance feature tracking strain analyses. The associations between diabetes and LV/LA impairment were investigated by univariable and multivariable linear regression. Results: Compared with the isolated HCM controls, the HCM-DM patients had smaller end-diastolic volume and stroke volume, lower ejection fraction, larger mass/volume ratio and impaired strains in all three directions (all P < 0.05). In terms of the LA parameters, HCM-DM patients presented impaired LA reservoir and conduit strain/strain rate (all P < 0.05). Among all HCM patients, comorbidity with diabetes was independently associated with a low LV ejection fraction (β = − 6.05, P < 0.001) and impaired global longitudinal strain (β = 1.40, P = 0.007). Moreover, compared with the isolated HCM controls, HCM-DM patients presented with more myocardial fibrosis according to late gadolinium enhancement, which was an independent predictor of impaired LV global radial strain (β = − 45.81, P = 0.008), LV global circumferential strain (β = 18.25, P = 0.003), LA reservoir strain (β = − 59.20, P < 0.001) and strain rate (β = − 2.90, P = 0.002). Conclusions: Diabetes has adverse effects on LV and LA function in HCM patients, which may be important contributors to severe manifestations and outcomes in those patients. The present study strengthened the evidence of the prevention and management of diabetes in HCM patients. [ABSTRACT FROM AUTHOR]

Background: Patients with concomitant type 2 diabetes mellitus (T2DM) and aortic regurgitation (AR) can present with right ventricular (RV) dysfunction. The current study aimed to evaluate the impact of AR on RV impairment and the importance of ventricular interdependence using cardiac magnetic resonance feature tracking (CMR‑FT) in patients with T2DM. Methods: This study included 229 patients with T2DM (AR−), 88 patients with T2DM (AR+), and 122 healthy controls. The biventricular global radial strain (GRS), global circumferential strain (GCS), and global longitudinal peak strain (GLS) were calculated with CMR‑FT and compared among the healthy control, T2DM (AR−), and T2DM (AR+) groups. The RV regional strains at the basal, mid, and apical cavities between the T2DM (AR+) group and subgroups with different AR degrees were compared. Backward stepwise multivariate linear regression analyses were performed to determine the effects of AR and left ventricular (LV) strains on RV strains. Results: The RV GLS, LV GRS, LV GCS, LV GLS, interventricular septal (IVS) GRS and IVS GCS were decreased gradually from the controls through the T2DM (AR−) group to the T2DM (AR+) group. The IVS GLS of the T2DM (AR−) and T2DM (AR+) groups was lower than that of the control group. AR was independently associated with LV GRS, LV GCS, LV GLS, RV GCS, and RV GLS. If AR and LV GLSs were included in the regression analyses, AR and LV GLS were independently associated with RV GLS. Conclusion: AR can exacerbate RV dysfunction in patients with T2DM, which may be associated with the superimposed strain injury of the left ventricle and interventricular septum. The RV longitudinal and circumferential strains are important indicators of cardiac injury in T2DM and AR. The unfavorable LV-RV interdependence supports that while focusing on improving LV function, RV dysfunction should be monitored and treated in order to slow the progression of the disease and the onset of adverse outcomes. [ABSTRACT FROM AUTHOR]

Exciton-driven strong light–matter interactions in two-dimensional materials have displayed their advantages in applications in optoelectronics and photonics. However, the large exciton binding energy prohibits the efficient separation of photoexcited electron–hole pairs and is unfavorable for the application of photoelectrics and photovoltaics. Here, based on density-functional theory with the many-body perturbation method, we study the evolution of quasiparticle band structure, exciton, and optical properties with biaxial strain in 2D Hittorf's phosphorene. The pristine and +1% strained Hittorf's phosphorene are direct-band-gap semiconductors with the valence band maximal and the conduction band minimal located at the X point. When strain is approaching +2%, the conduction band minimal changes from the X point to the Γ point, resulting in a transition to the indirect band gap. This kind of indirect band gap persists to +5%. For the optical gap, we observe a modulation threshold of 0.33 eV over a +5% strain range. It is revealed that a p–n junction with efficient electron–hole excitation and separation is naturally formed in inhomogeneously strained 2D membrane. The transition from direct-band-gap to indirect-band-gap semiconductor, the strongly enhanced exciton lifetime, and the spatial separation of photoexcited electron–hole pairs under a moderate electric field will further inhibit the recombination. Together with the efficient visible light absorption which guarantees the absorption of solar spectra, these findings provide an effective avenue toward solar energy harvesting. [ABSTRACT FROM AUTHOR]

This study investigates the impact of different annealing temperatures on the properties of zinc oxide (ZnO) films, particularly at lower temperatures (150-550°C). The films were synthesized using the sol-gel technique, with zinc acetate dihydrate (ZAD) as the precursor and ethanolamine (MEA) as the stabilizing agent. Surface morphology, structural, and optical properties of the films were examined using various techniques. X-ray diffraction confirmed the (002) wurtzite crystal structure, while crystallite size, strain, stress, energy density model, and dislocation density are estimated using three models of Williamson-Hall (W-H) approach.Raman data indicated the hexagonal wurtzite structure of the film. Optical analysis showed good transmittance, with a bandgap estimated between 3.32 and 3.56 eV for all samples. SEM image analysis revealed a nanowall structure in the ZnO thin film annealed at 150°C. However, increasing the annealing temperature led to a more pronounced wrinkled morphology. [ABSTRACT FROM AUTHOR]

We focus on estimating the influences of uniaxial tensile and shear strains on a band gap in the electronic structure of monolayer black phosphorus. To study numerically the dependence of the band gap on the deformation type and strength, we apply two approaches: the tight-binding model (with the exponential and inversely quadratic strain-induced bond-length-dependent hoppings) and the density-functional-theory-based calculations. Both approaches corroborated that phosphorene as a direct semiconductor in the unstrained state can become a semimetal at certain types and strengths of deformations. The critical values of the semiconductor–semimetal transition are different depending on approximations and model parameters. [ABSTRACT FROM AUTHOR]

Strain engineering has been used as a versatile tool for regulating the thermal transport in various materials as a result of the phonon frequency shift. On the other hand, the phononic bandgap can be simultaneously tuned by the strain, which can play a critical role in wide phononic bandgap materials due to the high-order phonon anharmonicity. In this work, we investigate the complex role of uniaxial tensile strain on the lattice thermal conductivity of hydrogenated graphene-like borophene, by using molecular dynamics simulations with a machine learning potential. Our findings highlight a novel and intriguing phenomenon that the thermal conductivity in the armchair direction is non-monotonically dependent on the uniaxial armchair strain. Specifically, we uncover that the increase of phonon group velocity and the decrease of three-phonon scattering compete with the enhancement of four-phonon scattering under armchair strain, leading to the non-monotonic dependence. The enhanced four-phonon scattering originates from the unique bridged B–H bond that can sensitively control the phononic bandgap under armchair strain. This anomalous non-monotonic strain-dependence highlights the complex interplay between different mechanisms governing thermal transport in 2D materials with large phononic bandgaps. Our study offers valuable insights for designing innovative thermal management strategies based on strain. [ABSTRACT FROM AUTHOR]

This paper outlines an experimental investigation into the durability of large-scale adhesively bonded joints with a thick layer of methyl methacrylate adhesive (MMA). Ageing has been performed by immersion in a 3.5 wt% NaCl solution for 10 weeks at 50°C. Two aged and one unaged specimen were subjected to tensile testing, and three aged and one unaged specimen were loaded up to ~ 3.5 million fatigue cycles followed by a residual tensile test. The ductility of the adhesive is affected by ageing and fatigue testing. Despite a decrease in ductility, the plastic zone development was adequate for the required strain redistribution without compromising the joint performance (strength and stiffness) demonstrating the fatigue tolerance of the joint. The shear, longitudinal, and peel strain values in the adhesive bulk are evaluated by digital image correlation. The shear strength values are significantly higher than the requirements following from the design. All specimens failed by sudden delamination of the composite plate. Post-mortem analysis showed no corrosion travel at the interface of steel and adhesive. [ABSTRACT FROM AUTHOR]

Due to insufficient backfilling and compaction, voids existing around the bottom of a buried pipe can have a negative effect on the mechanical behavior of the pipe. Expanded polystyrene (EPS) has been widely utilized in civil engineering as fill, backfill, moisture cutoff, and impact mitigation materials for falling rocks because of its light weight and workability. In this study, centrifuge model tests were conducted in order to investigate the possibility of pipe failure when voids existed around the bottom of the buried pipe, and the effect of installing EPS blocks as a countermeasure. In the test, a model polyvinyl chloride (PVC) pipe having a diameter of 140 mm was buried in the dry sand and loaded at the ground surface in a centrifugal field of 21G. Cases with voids around the bottom of the buried pipe and with EPS blocks were studied, and the differences in the pipe mechanical behavior under standard backfill conditions were discussed. The loading conditions and the shape of the EPS were varied. The test results showed that the loss of soil around the bottom of the pipe caused a stress concentration by a factor of more than 2.5 compared to the typical burial condition, and could directly cause pipe failure. In addition, it is clear that EPS installation was an effective countermeasure to avoid the risk of insufficient compaction, because it did not significantly affect pipe deformation and strain distribution, although the earth pressure tended to concentrate slightly at the bottom of the pipe. Practical Applications: Pipelines that are buried in the ground usually need to be backfilled uniformly with soil around the pipe. However, due to difficulties in construction, the backfilling and compaction may be insufficient on the bottom sides of the pipe, resulting in voids or localized low-density areas. In this study, centrifuge model tests were conducted to investigate the behavior of pipes buried in such nonuniform ground and the effectiveness of a countermeasure to install expanded polystyrene foam (EPS) blocks as a foundation instead of backfilling with soil. In the tests, a 150-mm-diameter polyvinyl chloride (PVC) pipe was buried in a container, and the strain of the pipe was measured in detail when a vertical load of up to 140 kPa was applied to the ground surface in a 20G centrifugal force field. As a result, when the soil in the lower part of the pipe is not uniform, a large strain is concentrated at the bottom of the pipe, which may lead to the pipe failure. Then, when EPS was installed, no large strains were measured, indicating that EPS installations are effective as a countermeasure. [ABSTRACT FROM AUTHOR]

Background: Aging populations and nursing workforce issues are causing challenges for long-term care globally, and therefore, improving the work-related wellbeing and retention of nurses is crucial. As such, gaining a further understanding of the factors that affect work strain in long-term care is important. Previously, the effect of job demands on the wellbeing of nurses has been researched principally by subjective instruments. In this study, we examined the relationship between indirectly measured workday characteristics and perceived stress and time pressure among nurses working in Finnish long-term care (assisted living facilities with 24-hour assistance). Methods: A total of 503 nurses from 44 assisted living facilities across Finland completed time measurement surveys and wellbeing questionnaires. The data were linked with client characteristics from the Resident Assessment Instrument register. The relationships between the measured number of care events during the workday, clients' care needs, and the amount of breaktime and perceived stress and time pressure were analyzed using multivariate logistic regression. Results: Nurses who had more care events and clients with greater care needs were at higher odds of having high stress. More care events and reduced breaktime were associated with high time pressure. Disruptions during the workday were strongly associated with both high stress and time pressure. Last, nurses who were under high stress and time pressure worked more often in teams with lower team autonomy. Conclusions: Our findings on indirectly measured job demands indicate that dividing the workload equally among nurses through better work division can help reduce the stress and time pressure of nurses in long-term care. In addition, ensuring sufficient breaktime and preventing unnecessary disruptions is important. To help recruit and retain the care workforce, fair management of work that accounts for varying client care needs and workload is needed. In addition, legislative and governance tools, such as staffing level regulation, and further consideration of job demands might aid in reducing the job strain of nurses. Patient or public contribution: Patients or nurses were not involved in the design of the study, analysis, or interpretation of the results, or in the preparation of the manuscript. [ABSTRACT FROM AUTHOR]

This work reports a study of the fatigue behaviour and quasi‐static strength of full‐scale adhesively bonded steel‐composite joints. Three joints with an approximately 10‐mm‐thick layer of methyl methacrylate adhesive were manufactured in dockyard conditions. One specimen was tensile tested till failure, while two specimens were subjected to ~3.5 million fatigue cycles, followed by a residual tensile test supported with digital image correlation. The shear, longitudinal and peel strain values within the adhesive bondlines are significantly higher at the gripped sides due to the asymmetrical design of the steel brackets. All specimens showed a significantly higher shear strength than the design values defined by the shipbuilder. Fibre Bragg sensors monitored strains at steel and composite constituents and allowed to detect damage onset and evolution in tensile tested specimens. A finite element model of the joint was developed with material and interface properties based on dedicated small‐scale experiments. The simulation results of strains during a static load test corresponded closely to the DIC measurements. All specimens failed near the composite‐adhesive interface due to delamination of the composite panel. [ABSTRACT FROM AUTHOR]

Although there are methods to identify regions of interest (ROIs) from echocardiographic images of myocardial tissue, they are often time-consuming and difficult to create when image quality is poor. Further, while myocardial strain from ultrasound (US) images can be estimated, US alone cannot obtain functional information, such as oxygen saturation (sO 2). Photoacoustic (PA) imaging, however, can be used to quantify sO 2 levels within tissue non-invasively. Here, we leverage deep learning methods to improve segmentation of the anterior wall of the left ventricle and apply both strain and oxygen saturation analysis via segmentation of murine US and PA images. Data revealed that training on US/PA images using a U-Net deep neural network can be used to create reproducible ROIs of the anterior wall of the left ventricle in a murine image dataset. Accuracy and Dice score metrics were used to evaluate performance of the neural network on each image type. We report an accuracy of 97.3% and Dice score of 0.84 for ultrasound, 95.6% and 0.73 for photoacoustic, and 96.5% and 0.81 for combined ultrasound and photoacoustic images. Rapid segmentation via such methods can assist in quantification of strain and oxygenation. [ABSTRACT FROM AUTHOR]

Maintaining vacuum integrity for the semiconductor manufacturing processes is extremely important to improve semiconductor fab productivity. The expensive machinery and the enormous costs of production downtime require reliable sealing systems which are designed to operate the longest possible preventative maintenance (PM) cycles. Being able to predict the lifetime of the sealing systems can help determine the optimum maintenance periods and hence increase profitability in costly wafer processing. The present contribution describes a finite element method to predict the lifetime of vacuum sealing systems limited by aging effects of the elastomer. Several different applications are considered including isothermal and non-isothermal conditions. Furthermore, homogeneous and inhomogeneous temperature fields are analyzed. Finally, the model predictions are compared to experimental data. [ABSTRACT FROM AUTHOR]

Context: This study explores the impact of deformation on the electrical and optical characteristics of monolayer cadmium telluride (MoTe2) with vacancies, using the foundational principles of density functional theory. It was discovered that both strain and imperfections alter the electrical characteristics of monolayer MoTe2. Under VTe-MoTe2, a direct-to-indirect band-gap transition occurs. In DTe-MoTe2, the band-gap value reduces dramatically, the conduction band changes downward, and the carrier concentration rises. The DVTe-induced band gap state is closer to the Fermi energy level than the VTe-induced band gap state. In this paper, DTe-MoTe2 is chosen for tensile deformation. The results show that the band-gap value tends to decrease by increasing tensile deformation. When the stretching value reaches 10%, the lower bound of the conduction band and the top of the valence band overlap, and the system is converted from a semiconductor to a metal. Considering the density of states, the missing state MoTe2 is mainly contributed by the participation of Te-s, Te-p, and Mo-d orbitals. In terms of optical qualities, the absorption and reflection peaks are red-shifted and blue-shifted, respectively. It is hoped that these effects on the optoelectronic properties will be widely applied. Methods: In this study, we utilize the generalized gradient approximation plane-wave pseudopotential method, incorporating Perdew-Burke Ernzerhof (PBE) generalized functions and following the fundamental principles of the density functional theory framework. A 3 × 3 × 1 supercell was constructed as an undoped model based on a MoTe2 monolayer, which consists of 9 Mo atoms and 18 Te atoms. The vacuum flat plate was set to 15 Å along the z-direction to avoid interactions between the monolayers. For electronic structure calculations, the energy cutoff was set to 450 eV. Each model's computational process and structural optimization were carried out using the Monkhorst–Pack specialized K-point sampling approach. Crystal optimization computations used a 3 × 3 × 1 Monkhorst–Pack K-point grid for molybdenum ditelluride monolayers and a 9 × 9 × 1 K-point grid for electronic system analysis, analyzing state density and optical characteristics, respectively. For the structural optimization, the convergence requirements for maximum force, maximum atom displacement, maximum stress, and energy change were defined at 0.03 eV/Å, 0.001 Å, 0.05 Gpa, and 1.0 × 10−5 eV/atom, respectively. [ABSTRACT FROM AUTHOR]

The stress–strain diagram of a polymer composite material based on rubber PDI-3A filled with thermally expanded graphite or potassium chloride has been studied before and after microwave treatment for 300, 600, 900, and 1200 s. It has been found that the ultimate tensile strength and strain increase twofold after a 300-s microwave treatment and testing at 223 K. A significant decrease in the stress–strain properties of the synthesized composites with an increase in the test temperature or microwave treatment time is observed. [ABSTRACT FROM AUTHOR]

In the internal parts of the Zagros collision zone, several deformation phases have been superimposed. The early deformation phase caused the development of a penetrative foliation. The late‐stage deformation phase was preferentially accommodated within shear zones and caused the generation of shear bands, implying a non‐coaxial component of deformation, the end of this stage deformation was marked by the development of kink‐bands. In the vicinity of Zagros suture zone, the kink angle increased from 40° to 60°, and the kink‐bands was converted to chevron folds. In this region, the external (α) and internal (β) angular ratio is α/β ≠ 1 and kink angle increased, and deformation occurred with 10% to 30% volume loss. Farther from the suture zone in the east, α/β = 1; and total volume was constant or increased by 5% to 10%. Kink‐bands kinematic analysis in the study area revealed this structures were sensitive to deformation conditions and components such that, with decreasing distance to the Zagros suture zone, shearing and rotation increased, a high kinematic vorticity dominated, and volume loss occurred during deformation. [ABSTRACT FROM AUTHOR]

The effects of -F functional group on the structure, electronic properties and magnetic properties of Janus-type MXene 2D material CrVC were studied by first-principles of density functional theory. The calculation results indicate that the -F functional group changes the electronic properties and magnetic properties of CrVC. The nine possible structures of CrVCF2 exhibit ferromagnetic behavior, among which the structure of CrVCF2 -33 has the lowest energy and is the ground state, with a magnetic moment of 5. 01 μB and a band gap of 0. 099 eV, exhibiting semiconductor characteristics. The total magnetic moment of CrVCF2 -33 remains unchanged when - 4% - + 4% biaxial strain is applied; the energy increases with either compression or tension strain, but the change is less than 0. 2 eV; the band gap changes under the action of strain, when the tensile strain is 2. 4%, the band gap decreases to 0. 005 eV, which is close to zero. It can be considered a spin-zero band gap semiconductor. The results show that moderate strain can adjust the electronic structure of the CrVCF2 material, and it can even become a spin-zero band gap semiconductor, indicating its potential application value in the field of spintronics. [ABSTRACT FROM AUTHOR]

Cardiac resynchronization therapy (CRT) is an established therapy for advanced heart failure (HF) with prolonged QRS duration. However, 30% of patients have shown no benefit from the treatment. This study aimed to examine the value of left atrial (LA) mechanics by cardiac magnetic resonance (CMR) to predict response to CRT and clinical outcomes. A total of 163 CRT recipients with preimplantation CMR examination were retrospectively recruited. CMR feature tracking was used to evaluate LA size and function. The end points include (1) improvement of at least 5% in left ventricular ejection fraction combined with a reduction of at least 1 New York Heart Association functional class at 6-month follow-up and (2) any all-cause death or HF hospitalization during follow-up. Overall, 82 (50.3%) were CRT responders. CRT nonresponders had larger LA and worse LA reservoir and booster pump function than did responders (P <.001 for all). LA structural (maximum volume index < 47 mL/m2) and functional (booster pump strain > 8.5%) criteria were incremental to traditional indicators in detecting CRT response (χ2, 40.83 vs 9.98; P <.001). During follow-up (median 41 months), survival free from death or HF hospitalization increased with the number of positive LA criteria (log-rank, P <.001). After adjustment for clinical confounders, the absence of the 2 criteria remained associated with a considerably increased risk of death or HF hospitalization (adjusted hazard ratio 6.2; 95% confidence interval 2.15–17.88; P =.001). The preprocedure LA mechanics evaluated using CMR may be useful to predict response to CRT and improve risk stratification in CRT recipients. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Individuals suffering from chronic kidney disease (CKD) frequently face a heightened likelihood of experiencing cardiovascular complications, including heart failure and cardiac mortality. Cardiovascular magnetic resonance feature tracking (CMR-FT) is utilized to assess the micro-contraction function of the myocardium. The objective of this research is to explore the relationship between the left ventricular anatomy, myocardial strain, and the clinical outcomes in patients with CKD. Methods: A total of 77 patients with late-stage CKD were enrolled in this retrospective study. They underwent cardiac magnetic resonance imaging and were followed up, with no history of significant cardiac diseases. The patients were divided into two groups: those with a left ventricular global longitudinal strain (LVGLS) ≥ −15.2% (n = 49) and those with LVGLS < −15.2% (n = 28). The clinical endpoints were defined as hospitalization for heart failure or all-cause mortality. Results: Over an average observation period of 22 ± 9 months, 11 (14%) patients passed away and 30 (39%) were admitted to the hospital for heart failure, with eight encountering both incidents. Those with LVGLS ≥ −15.2% had markedly lower rates of event-free survival concerning heart failure admissions and overall mortality than their counterparts (log-rank P = 0.014). Cox multivariable analysis indicated that reduced LVGLS consistently predicted a higher likelihood of combined outcomes of heart failure admissions and total mortality (HR: 3.40, 95% CI [1.35–8.56], P = 0.009), even when factoring in age, diabetes, left atrial diameter, and left ventricular mass index (LVMI). However, the LVMI showed no significant correlation with the risk of heart failure admissions or overall mortality. Conclusion: Compared to patients with LVGLS < −15.2%, CKD patients with LVGLS ≥ −15.2% have an increased risk of heart failure hospitalization and all-cause mortality. The prognostic role of LVMI in assessing CKD patients among the Asian population requires further investigation. [ABSTRACT FROM AUTHOR]

Recorded head kinematics from head-impact measurement devices (HIMd) are pivotal for evaluating brain stress and strain through head finite element models (hFEM). The variability in kinematic recording windows across HIMd presents challenges as they yield inconsistent hFEM responses. Despite establishing an ideal recording window for maximum principal strain (MPS) in brain tissue, uncertainties persist about the impact characteristics influencing vulnerability when this window is shortened. This study aimed to scrutinize factors within impact kinematics affecting the reliability of different recording windows on whole-brain peak MPS using a validated hFEM. Utilizing 53 on-field head impacts recorded via an instrumented mouthguard during a Canadian varsity football game, 10 recording windows were investigated with varying pre- and post-impact-trigger durations. Tukey pair-wise comparisons revealed no statistically significant differences in MPS responses for the different recording windows. However, specific impacts showed marked variability up to 40%. It was found, through correlation analyses, that impacts with lower peak linear acceleration exhibited greater response variability across different pre-trigger durations. Signal shape, analyzed through spectral analysis, influenced the time required for MPS development, resulting in specific impacts requiring a prolonged post-trigger duration. This study adds to the existing consensus on standardizing HIMd acquisition time windows and sheds light on impact characteristics leading to peak MPS variation across different head impact kinematic recording windows. Considering impact characteristics in research assessments is crucial, as certain impacts, affected by recording duration, may lead to significant errors in peak MPS responses during cumulative longitudinal exposure assessments. [ABSTRACT FROM AUTHOR]

The aim of this study is to assess the feasibility of compressed sensing (CS) acceleration methods compared to conventional segmented cine (Seg) cardiac magnetic resonance (CMR) for evaluating left ventricular (LV) function and strain by feature tracking (FT). In this prospective study, 45 healthy volunteers underwent CMR imaging used Seg, threefold (CS3), fourfold (CS4), and eightfold (CS8) CS acceleration. Cine images were scored for quality (1–5 scale). LV volumetric and functional parameters and global longitudinal (GLS), circumferential (GCS), and radial strains (GRS) were quantified. LV volumetric and functional parameters exhibited no differences between Seg and all CS cines (all P > 0.05). The strains were similar for Seg, CS3, and CS4 (all P > 0.05). Similarly, no significant differences were observed in GRS and GCS between Seg and CS8 (all P > 0.05), but the global longitudinal strain was significantly lower for CS8 versus Seg (P < 0.001). Image quality declined with CS acceleration, especially in long-axis views with CS8. CS cine MRI at acceleration factor 4 maintained good image quality and accurate measurements of LV function and strain, although there was a slight reduction in the quality of long-axis images and GLS with CS8. CS acceleration up to a factor of 4 enabled fast CMR evaluations, making it suitable for clinical use. [ABSTRACT FROM AUTHOR]

Background: Patients with repaired tetralogy of Fallot (rTOF) continue to face a heightened risk of deteriorating cardiac function, and quantitative techniques of cardiac MRI‐derived cardiac structure and function provide an opportunity to explore the causes and mechanisms of cardiac deterioration. Purpose: To explore right–left ventricular interdependence in rTOF patients before and after the onset of right ventricular (RV) heart failure. Study Type: Retrospective. Population: One hundred eighteen rTOF patients (21.85 [16.74, 29.20] years, 58 females) and 34 controls (23.5 [21, 26.5] years, 17 females) that underwent cardiac MRI were analyzed, with rTOF patients being further subdivided into those with preserved RV function (N = 54) and those that experienced RV heart failure (N = 64). Field Strength/Sequence: 3.0 T/balanced steady‐state free precession sequence. Assessment: RV, left ventricular (LV), and septal strain; RV and LV volume. Statistical Tests: Chi‐squared tests or Fisher's exact test, One‐way ANOVAs with Bonferroni's post hoc test, Pearson/Spearman correlation, and multivariate backward linear regression analysis. A two‐tailed P < 0.05 was deemed as the significance threshold. Results: The MRI‐derived RV, LV, and septal strain decreased sequentially in controls, patients with preserved RV function, and patients with RV heart failure, with a good intra‐observer (0.909–0.964) and inter‐observer (0.879–0.937) agreement. Correlations between LV and RV strain were found to change sequentially with RV function and were the closest in rTOF patients with RV heart failure (r = −0.270 to 0.506). Correlations between RV volume and septal strain was variable in controls (r = 0.483 to −0.604), patients with preserved RV function (r = −0.034 to −0.295), and patients with RV heart failure (r = −0.026 to 0.500). Multivariate analyses revealed that the RV longitudinal strain was independently correlated with LV strain in three directions in rTOF patients with RV heart failure (Radial −0.70 [−1.33, −0.06]; Circumferential 0.44 [0.17, 0.72]; Longitudinal 0.54 [0.26, 0.81]). Data Conclusion: In rTOF patients, the coupling between RV volume and septal strain was broken during RV function compensation, and the adverse effect of RV on LV deformation was highest in patients with RV heart failure. Evidence Level: 4 Technical Efficacy: Stage 5 [ABSTRACT FROM AUTHOR]

At present, almost 50% of electrical power is consumed by motors. Thus, increasing the efficiency of motors is an important issue. To achieve more efficient operation, it is vital to improve the accuracy of input data for motor loss design. In this study, we focused on the iron loss of electromagnetic steels, which is assumed to account for a large proportion of motor losses, and examined whether the effect of stress on the iron loss and its frequency dependence could be predicted with high accuracy by machine learning. First, experimental iron loss data are obtained at flux densities of 0.1-1.7 T, frequencies of 50-3000 Hz, and applied stresses from 200 to 200 MPa. No significant deterioration in iron loss behavior is observed in specimens subjected to 3% and 10% pre-strain by tensile loading. These data show that the effect of stress on iron loss varies significantly depending on the excitation conditions. The complex iron loss behaviors are the result of interplay between magnetic wall movement and magnetic domain rotation during the magnetization process. As simple regression of the magnetization process is difficult, we apply three machine learning algorithms to the experimental dataset. The results show that the LightGBM algorithm produces the most accurate predictions of the experimental iron loss values. The contributions of the explanatory variables are found to be consistent with empirical knowledge. This study demonstrates the potential for machine learning to enable improve the accuracy of iron loss data input to motor loss design. [ABSTRACT FROM AUTHOR]

The effects of -F functional group on the structure, electronic properties and magnetic properties of Janus-type MXene 2D material CrVC were studied by first-principles of density functional theory. The calculation results indicate that the -F functional group changes the electronic properties and magnetic properties of CrVC. The nine possible structures of CrVCF2 exhibit ferromagnetic behavior, among which the structure of CrVCF2 -33 has the lowest energy and is the ground state, with a magnetic moment of 5. 01 μB and a band gap of 0. 099 eV, exhibiting semiconductor characteristics. The total magnetic moment of CrVCF2 -33 remains unchanged when - 4% - + 4% biaxial strain is applied; the energy increases with either compression or tension strain, but the change is less than 0. 2 eV; the band gap changes under the action of strain, when the tensile strain is 2. 4%, the band gap decreases to 0. 005 eV, which is close to zero. It can be considered a spin-zero band gap semiconductor. The results show that moderate strain can adjust the electronic structure of the CrVCF2 material, and it can even become a spin-zero band gap semiconductor, indicating its potential application value in the field of spintronics. [ABSTRACT FROM AUTHOR]

Background: Left atrial (LA) strain, comprising LA reservoir, conduit and contractile function could add mechanistic information of patients after arterial switch operation (ASO) for transposition of the great arteries (TGA). ASO patients might have abnormal ventriculoarterial coupling, which makes them vulnerable to left ventricle (LV) dysfunction and results in reduced exercise capacity. This explorative study aimed to evaluate the relation between LA strain, atrial size, ventricular function, and exercise data obtained by cardiopulmonary exercise testing (CPET). Methods: In a cohort of 44 patients (71% male, mean age 25 ± 4 years) LA strain was measured using transthoracic speckle-tracking echocardiography. Further assessment involved standard echocardiography, CPET evaluation, and blood sampling. LA strain values were compared to normal values. Correlations were calculated. Regression analysis with all strain variables to the CPET data was performed. Results: LA reservoir, conduit and contractile strain were normal in 30%, 89% and 50% of the patients, respectively. LA reservoir/contractile strain correlated to LV ejection fraction (ρ 0.310/−0.159, respectively) and LA reservoir/conduit strain correlated to the LA volume index (ρ 0.336/−0.357, respectively). None of the individual LA strain parameters were associated with the CPET variables. In multivariate regression analysis, LA contractile strain was significantly associated with the percentage of predicted maximal heart rate (β − 2.555). Conclusions: These data suggest that in TGA patients after ASO repair LA strain is impaired and correlates with LA size and LV function. However, impaired LA strain wasn't associated with the standard CPET parameters. As such, clinical significance needs to be further unravelled. [ABSTRACT FROM AUTHOR]

Geogrid is a horizontal reinforcement material that is used in geosynthetic-reinforced pile-supported (GRPS) embankments in freeways with soft soil. Nevertheless, the long-term deformation mechanics of geogrid in the GRPS embankment under cyclic loading is not clear enough. This paper presents a laboratory model study of a GRPS embankment to study the long-term geogrid strain under cyclic loading. The effects of parameters such as number of load cycles, load frequency, geogrid layer numbers, and length of supporting piles on the long-term strain of geogrid were investigated. The results showed that geogrid strain increased with the number of load cycles, mainly developed in the first 10 000 load cycles and increased slowly in the later period. When the frequency was increased from 1 to 5 Hz, geogrid strain increased dramatically. When compared with the condition of a single geogrid layer, the upper layer of two geogrid layers caused a less geogrid strain. Compared with long piles and short piles GRPS embankments, a sufficient membrane effect of geogrid was found for long-short piles GRPS embankments. Finally, the 95% prediction interval proposed in this paper could be expressed using a logarithmic function, providing a theoretical foundation for future engineering applications. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) morbidity and mortality are high among black adults. We aimed to study the granular subclinical relations of aortic stiffness and left ventricular (LV) function and remodeling in blacks, in whom limited data are available. In the Jackson Heart Study, 1050 U.S. community-dwelling black adults without CVD underwent 1.5 T cardiovascular magnetic resonance. We assessed regional and global aortic stiffness and LV structure and function, including LV mass indexed to body surface area (LVMI), end-diastolic volume (LVEDV), ejection fraction (EF), and global and regional circumferential strain (Ecc). Phase contrast images of the cross-sectional aorta at the pulmonary artery bifurcation and abdominal aorta bifurcation were acquired to measure pulse wave velocity of the aortic arch (AA-PWV) and thoracic aorta (T-PWV). Results of multivariable-adjusted analyses are presented as SD unit change in LV variables per SD change in PWV variables. Participants were 62% women with mean age of 59 ± 10 years. Higher AA-PWV and T-PWV were associated with greater LVMI: for T-PWV, β = 0.10, 95% CI = 0.03–0.16, p = 0.002. Higher AA-PWV and T-PWV were associated with worse (more positive) Ecc at the LV base (for AA-PWV, β = 0.13, 95% CI = 0.05–0.20, p = 0.0007), but not mid-LV or apex. AA-PWV and T-PWV were not associated with LV mass/LVEDV or EF. In this cross-sectional study of blacks without CVD in the U.S., aortic stiffness is associated with subclinical adverse LV function in basal segments. Future studies may elucidate the temporal relationships of aortic stiffness on the pattern and progression of LV remodeling, dysfunction, and associated prognosis in blacks. [ABSTRACT FROM AUTHOR]

Mixed‐halide perovskites show promising applications in tandem solar cells owing to their adjustable bandgap. One major obstacle to their commercialization is halide phase segregation, which results in large open‐circuit voltage deficiency and J‐V hysteresis. However, the ambiguous interplay between structural origin and phase segregation often results in aimless and unspecific optimization strategies for the device's performance and stability. An atomic scale is directly figured out the abundant Ruddlesden‐Popper anti‐phase boundaries (RP‐APBs) within a CsPbIBr2 polycrystalline film and revealed that phase segregation predominantly occurs at RP‐APB‐enriched interfaces due to the defect‐mediated lattice strain. By compensating their structural lead halide, such RP‐APBs are eliminated, and the decreasing of strain can be observed, resulting in the suppression of halide phase segregation. The present work provides the deciphering to precisely regulate the perovskite atomic structure for achieving photo‐stable mixed halide wide‐bandgap perovskites of high‐efficiency tandem solar cell commercial applications. [ABSTRACT FROM AUTHOR]

Small, strained carbocyclic systems have fascinated organic chemists from both a theoretical and synthetic standpoint. These systems often challenge conventional wisdom when it comes to molecular structure and tactics for chemical construction. The cyclopropyl motif is one such ring system that remains at the forefront of method development in the modern era. With the advent of an array of non‐traditional building blocks, a range of new cyclopropanation processes using one‐ and two‐electron strategies have been developed that not only overcome the synthetic shortcomings of classical approaches but also provide entry into a wide range of new classes of cyclopropanes. This review discusses recent advances in this area with an emphasis on their mechanistic underpinnings and potential applications. Additionally, a concise overview of the properties of and traditional approaches to cyclopropanes is provided. [ABSTRACT FROM AUTHOR]

Defects on horizontal axis wind turbine blades are difficult to identify and monitor with conventional forms of non-destructive examination due to the blade's large size and limited accessibility during continuous operation. This article examines both strain and acceleration transmissibility as methods of continuous damage detection on wind turbine blades. A scaled 117 cm offshore wind turbine blade was first designed, 3D printed, and modelled numerically in ANSYS. Transverse cracks were deliberately introduced to the blade at 10 cm intervals along its leading edge. Subsequent changes in the transmissibility, relative to an undamaged baseline model, were measured using different variable combinations at the blade's first three natural frequencies. Experimental results indicated that strain transmissibility was able to locate a 1.0 cm defect at a range of 70–110 cm from the blade hub using the amplitudes of the first natural frequency of vibration. The numerical model was able to simulate the strain experimental results and was determined to be valid for future defect characterization. Acceleration transmissibility was unable to experimentally identify defects sized at 1.0 cm and below but was able to identify 1.0 cm sized defects numerically. It was concluded that transmissibility is viable for continuous damage detection on blades but that further research into other defect types and locations is required prior to conducting full-scale testing. [ABSTRACT FROM AUTHOR]

Two‐dimensional ultrasound (2DUS) echocardiography is the main noninvasive method used to evaluate cardiac function in animal models of myocardial infarction (MI). However, 2DUS echocardiography does not capture regional differences in cardiac contractility since it relies on planar images to estimate left ventricular (LV) geometry and global function. Thus, the current study was designed to evaluate the efficacy of a newly developed 4‐dimensional ultrasound (4DUS) method in detecting cardiac functional differences between two models of MI, permanent ligation (PL), and ischemia/reperfusion (I/R) in rats. We found that only 4DUS was able to detect LV global functional differences between the two models and that 4DUS‐derived surface area strain accurately detected infarcted regions within the myocardium that correlated well with histological infarct size analysis. We also found that 4DUS‐derived strain, which includes circumferential, longitudinal, and surface area strain, correlated with the peak positive of the first derivative of left ventricular pressure (+dP/dtmax). In conclusion, 4DUS strain echocardiography effectively assesses myocardial mechanics following experimentally induced ischemia in rats and accurately estimates infarct size as early as 1 day after injury. 4DUS also correlates well with +dP/dtmax, a widely used marker of cardiac contractility. [ABSTRACT FROM AUTHOR]

We report on the use of 2D Ruddlesden–Popper (RP) perovskites as optoelectronic materials in building-integrated applications, addressing the challenge of balancing transparency, photoluminescence, and stability. With the addition of polyvinylpyrrolidone (PVP), the 2D RP films exhibit superior transparency compared to their 3D counterparts with an average visible transmittance (AVT) greater than 50% and photoluminescence stability under continuous illumination and 85 °C heat for up to 100 h as bare, unencapsulated films. Structural investigations show a stress relaxation in the 3D perovskite films after degradation from thermal aging that is not observed in the 2D RP films, which retain their phase after thermal and light aging. We also demonstrate ultrasmooth, wide-bandgap 2D Dion–Jacobson (DJ) films with PVP incorporation up to 2.95 eV, an AVT above 70%, and roughnesses of ~2 nm. These findings contribute to the development of next-generation solar materials, paving the way for their integration into built structures. [ABSTRACT FROM AUTHOR]

This study examines the impact of sporadic rolling on the mechanical properties and microstructures of the Mg-8% Li/bagasse nanoparticle composite. Using the stir casting method, bagasse nanoparticle-reinforced composites were developed and rolled with thickness reductions of 50, 70, and 90%. Research on the microstructures of rolled composites shows that when aspect ratio decreases, fine, elongated grains grow in thickness and decrease in reduction. Additionally, it can be seen that by increasing the percentage of rolling, the β phase dissolves and the ductility of the composite is decreased. Comparing the interrupted rolled sample to the as-cast composite, the hardness is greater. At a 90% reduction, the yield has greater yield strength of 223 MPa. Because of the effective reduction in particle size, the hardening capability of composites reduces as the reduction percentage increases. It has been established that interrupted rolling affects the mechanical and microstructures of Mg-8% Li/bagasse nanoparticle composite. [ABSTRACT FROM AUTHOR]

In view of the problems that the mechanical seal for the water pump is prone to deformation, friction and wear, and loss of sealing performance in the process of use, taking the temperature change of end surface as the research entry point, the temperature distribution, stress and strain diagram of rotating ring, and stationary ring are obtained by thermal-stress coupling simulation. The temperature change of stationary ring is studied by the experiments, and the friction state of end surface of rotating ring and stationary ring are observed. The results indicate that the test temperature of stationary ring is slightly lower than simulation temperature, which is related to the thermocouple fixed on the side of the stationary ring for temperature measurement. In addition, comparing the micro morphology of end surface of rotating ring before and after the experiment, it is found that there is significant plastic deformation on the inner diameter of rotating ring, which is related to the stress generated by the thermal-mechanical coupling of inner diameter of rotating ring exceeding the material limit, consistent with the simulation results. [ABSTRACT FROM AUTHOR]

To provide scientific basis for the variety approval and promotion of the new cigar wrapper strain Chuanxue No. 2. Using Chuanxue No. 2 and other 8 cigar strains as experimental materials, regional experiments were conducted in 9 major cigar producing areas nationwide in 2021 and 8 major cigar producing areas nationwide in 2022. Results showed that the field of Chuanxue No. 2 was neat and strong, the field growth period was 88 days, it was immune to TMV, was resistant to root black rot, had strong comprehensive disease resistance, and the natu- ral incidence rate of the field was relatively low as a whole; The average yield was 1 533. 30 kg/hm², with an average output value of 83 234.70 Yuan/hm². The proportion of medium to top grade tobacco was 74.98%, and the yield, output value, proportion of medium to top grade tobacco, and total smoking score are ranked high among the 9 test strains. The overall performance of Chuanxue No. 2 was good, and it could be used for demonstration planting on a certain scale and research on related cultivation techniques. [ABSTRACT FROM AUTHOR]

Nanolayers of MoS2 can be grown to be used as active elements in nano-optoelectronic devices such as two-dimensional (2D) light emitters and optical detectors. The growth of 2D flakes might result in the formation of not only isolated triangles but also complex polycrystal flakes when different flakes interact during their in-plane expansion. In this paper, we investigate how monolayer MoS2 flakes of different shapes are affected by the biaxial strain resulting from the cooling process after chemical vapor deposition growth. The single- and polycrystal flakes are characterized at the nanoscale level by correlating morphological, electrical, and optical measurements and imaging. The main focus is given to the analysis of the exciton/trion photoluminescence (PL) components extracted from the spectra at different areas of the flake surface. According to the Raman imaging, the whole flake has built-in heterogeneous tensile strain, with the perimeter and the grain boundaries between the single-crystal parts of the poly flakes exhibiting a lower strain level (0.2–0.3%) and the central area being more strained (∼0.4%). At the perimeter and grain boundaries, the PL undergoes the strain-related blueshift accompanied by a weakening of the contribution of the long-wave trion to the spectrum and the trion binding energy. The trion formation is known to be proportional to a local electron concentration. The trion PL imaging compared to the surface potential mapping confirms a decrease in n-doping at the perimeter and grain boundaries, leading to the trion weakening. To confirm the results of electron drift to strained areas of the flake, creating the trion, the band bending at the tensile-strained flake has been theoretically calculated and modeled. The effect of edge defects at the perimeter and grain boundaries on the doping, which leads to the enhancement or inhibition of the trion formation depending on the edge and grain boundary interface type, is also discussed. [ABSTRACT FROM AUTHOR]

Lead based bulk piezoelectric materials, e.g., PbZrxTi1‐xO3 (PZT), are widely used in electromechanical applications, sensors, and transducers, for which optimally performing thin films are needed. The results of a multi‐domain Landau–Ginzberg‐Devonshire model applicable to clamped ferroelectric thin films are used to predict the lattice symmetry and properties of clamped PZT thin films on different substrates. Guided by the thermal strain phase diagrams that are produced by this model, experimentally structural transitions are observed. These can be related to changes of the piezoelectric properties in PZT(x = 0.6) thin films that are grown on CaF2, SrTiO3 (STO) and 70% PbMg1/3Nb2/3O3‐30% PbTiO3 (PMN‐PT) substrates by pulsed laser deposition. Through temperature en field dependent in situ X‐ray reciprocal space mapping (RSMs) and piezoelectric force microscopy (PFM), the low symmetry monoclinic phase and polarization rotation are observed in the film on STO and can be linked to the measured enhanced properties. The study identifies a monoclinic ‐rhombohedral MC‐MA‐R crystal symmetry path as the polarization rotation mechanism. The films on CaF2 and PMN‐PT remain in the same symmetry phase up to the ferroelectric‐paraelectric phase transition, as predicted. These results support the validity of the multi‐domain model which provides the possibility to predict the behavior of clamped, piezoelectric PZT thin films, and design films with enhanced properties. [ABSTRACT FROM AUTHOR]

Elasticity, featured by a recoverable strain, refers to the ability that materials can return to their original shapes after deformation. Typically, the elastic strains of most metals are well‐known 0.2%. In shape memory alloys and high entropy alloys, the elastic strains can be several percent, as called superelasticity, which are all triggered by external stresses. A superelasticity induced by magnetic field, termed as magneto‐superelasticity, is extremely important for contactless work of materials and for developing brand‐new large stroke actuators and high efficiency energy transducers. In magnetic shape memory alloys, the twin boundary motion driven by magnetic field can output a strain of several percent. However, this strain is unrecoverable when removing the magnetic field and hence it is not magneto‐superelasticity. Here, a giant magneto‐superelasticity of 5% in a Ni34Co8Cu8Mn36Ga14 single crystal is reported by introducing arrays of ordered dislocations to form preferentially oriented martensitic variants during the magnetically induced reverse martensitic transformation. This work provides an opportunity to achieve high performance in functional materials by defect engineering. [ABSTRACT FROM AUTHOR]

The automatic design of cap opening and closing of steel slag ball mill is the key to solve a series of problems caused by frequent cap opening and closing. In this paper, the automatic capping manipulator is designed for a steel slag ball mill in a factory, especially for the automatic tightening and loosening of the cap bolt, the grasping and transporting device of the cap, to ensure the safety and reliability of the design. [ABSTRACT FROM AUTHOR]

The hot compression tests of underwater vehicle metal material TC17 titanium alloy at deformation temperature of 800 ~ 950 °C and strain rate of 0,01 ~ 10 s-1 were carried out by Thermecmaster-Z thermal simulator. The hot deformation behavior of TC17 ferroalloy was studied. The effects of strain rate and deformation temperature on the high temperature forming of TC17 titanium alloy were analyzed. The multiple linear regression constitutive model of TC17 titanium alloy was established. The results show that the flow stress of TC17 alloy decreases with the increase of deformation temperature and increases with the increase of strain rate. The theoretical value of peak stress obtained by the multiple linear regression constitutive model of TC17 alloy is in good agreement with the experimental results, and the correlation is 97,25%. The model has high prediction accuracy. [ABSTRACT FROM AUTHOR]

In order to improve the quality of people 's travel and improve the performance of travel insulation cup, the thermal deformation behavior of 304 stainless steel, the edible grade material of travel insulation cup, was studied by Gleeble-3800 thermal / mechanical simulation machine. The true stress-strain curve of 304 stainless steel was obtained by hot compression test with deformation temperature of 800~1 100 °C and strain rate range of 0,001 ~ 1 s-1. According to the real stress-strain curve, the Arrhenius constitutive model of 304 stainless steel was constructed. The results show that the flow stress of 304 stainless steel increases with the increase of deformation temperature and strain rate. The theoretical stress value predicted by the constitutive model is fitted with the experimental results, and the correlation is 0,995, indicating that the model has high prediction accuracy. [ABSTRACT FROM AUTHOR]

Aim: Intermediate altitude (IA) is a risk factor for the development of cardiovascular disease due to low oxygen levels. At IA, adaptive mechanisms develop both in the pulmonary and systemic circulatory systems from an early period. The effects of IA on atrial functions were investigated in the present study by using speckle-tracking echocardiography. Materials and Methods: The present study was on the subjects living at IA for 1 year. The effects of IA on atrial functions were investigated by comparing the baseline and first-year echocardiographic data of the subjects. Results: A total of 67 subjects were included in this study. The mean age of the patients was 44.5 ± 6.2 years, and 62% of them were males. At the end of the first year, the left atrial (LA) conduit strain (p:0.011), reservoir strain (p:0.032), and contractile strain (p:0.037) rates were found to be significantly higher, whereas the left atrial volume index (p:0.005) was determined to be lower. Conclusion: IA leads to the development of adaptive mechanisms in the cardiovascular system, and the maintenance of tissue oxygenation is not affected by these mechanisms. These adaptive changes can be detected in LA structure and functions from the first year in individuals living at high altitudes. [ABSTRACT FROM AUTHOR]

Promalin (Valent BioSciences, Libertyville, IL, USA) is a proprietary mixture of gibberellin A4+7 and 6-benzyladenine that is widely used in apple production to improve the fruit shape, size, and skin quality. Promalin typically increases fruit size and length. However, the increased growth likely increases the strain in the fruit skin, which may exacerbate microcracking of the cuticle and, consequently, russeting. This study aimed to monitor the growth-stimulating effect of Promalin in three different regions of fruits and investigate whether Promalin affects cuticular microcracking via effects on the deposition of cuticular components or via the accumulation of strain in the cuticle. Four Promalin sprays (20 mg.L-1) were applied to runoff; the first was applied at full bloom, and the remaining sprays were applied at approximately weekly intervals thereafter. Fruit surface areas and fruit surface area growth rates of the Promalin-treated fruits were higher than those of the untreated control fruits. Promalin increased the fruit length, but it had no effect on the fruit equatorial diameter. In Promalin-treated fruits, the base of each sepal extended, thickened, and became fleshy as early as 15 days after full bloom (DAFB). Allometric growth analyses revealed higher constant differential growth ratios of the pedicel and calyx length (before 36 DAFB) in Promalin-treated fruits than in control fruits. After 36 DAFB, the difference in constant differential growth ratios between Promalin-treated fruits and control fruits decreased. Cuticle mass per unit area increased with time in all regions of the fruit surface and was slightly (+3.3%) but significantly higher in fruits treated with Promalin than in control fruits. Additionally, the biaxial strain release was slightly and significantly lower in Promalin-treated fruits than in control fruits. When the isolated, cuticle was ablated from the inner surface and dewaxed, strain relaxation in the control fruits was higher than that in the Promalin-treated fruits. It was concluded that Promalin treatment increases the length of the fruit by increasing the lengths of the pedicel and calyx regions early during fruit development. Promalin only slightly increased cuticle deposition and fixation of cuticular strain. Promalin had no effects on microcracking or russeting. [ABSTRACT FROM AUTHOR]

Herein, the structural, electronic, optical, and mechanical properties of Cu(I)Au(III)‐based double perovskites using first‐principles calculations are investigated. Phonon calculation results confirm that pure halide Cs2CuAuX6 (X = Cl, Br), mixed‐halide Cs2CuAuBr4Cl2 and Cs2CuAuI4Br2, and strained Cs2CuAuI6 (by 3% strain) are dynamically stable. Subsequently, the optoelectronic and mechanical properties of these compounds are calculated. The calculations reveal that Cs2CuAuX6 exhibits slightly indirect‐bandgap semiconducting behavior, with the bandgaps of 1.169, 1.191, and 1.355 eV from the HSE06 hybrid functional for X = Cl, Br, and I, respectively. Meanwhile, the bandgap of Cs2CuAuI6 decreases with the increase of strain from 1% to 3% (1.271, 1.148, and 1.037 eV, respectively). In addition, the results show that Cs2CuAuI4Br2 (EgHSE06 = 1.278 eV) has a suitable bandgap, which is close to the ideal direct bandgap. Moreover, Cs2CuAuI4Br2 exhibits strong anisotropic visible light absorption with absorption coefficients exceeding 105 cm−1 and has a relatively large dielectric constant (εxxst = εyyst = 36.27) along the ab plane. Furthermore, its Pugh's ratio (Poisson's ratio) value of 2.94(0.35) exceeds the critical value of 1.75(0.26), indicating its ductility and potential for use in flexible electronic devices. [ABSTRACT FROM AUTHOR]

Aspergillus fumigatus is a deadly fungal pathogen, responsible for >400,000 infections/year and high mortality rates. A. fumigatus strains exhibit variation in infection-relevant traits, including in their virulence. However, most A. fumigatus protein-coding genes, including those that modulate its virulence, are shared between A. fumigatus strains and closely related nonpathogenic relatives. We hypothesized that A. fumigatus genes exhibit substantial genetic variation in the noncoding regions immediately upstream to the start codons of genes, which could reflect differences in gene regulation between strains. To begin testing this hypothesis, we identified 5,812 single-copy orthologs across the genomes of 263 A. fumigatus strains. In general, A. fumigatus noncoding regions showed higher levels of sequence variation compared with their corresponding protein-coding regions. Focusing on 2,482 genes whose protein-coding sequence identity scores ranged between 75 and 99%, we identified 478 total genes with signatures of positive selection only in their noncoding regions and 65 total genes with signatures only in their protein-coding regions. Twenty-eight of the 478 noncoding regions and 5 of the 65 protein-coding regions under selection are associated with genes known to modulate A. fumigatus virulence. Noncoding region variation between A. fumigatus strains included single-nucleotide polymorphisms and insertions or deletions of at least a few nucleotides. These results show that noncoding regions of A. fumigatus genes harbor greater sequence variation than protein-coding regions, raising the hypothesis that this variation may contribute to A. fumigatus phenotypic heterogeneity. [ABSTRACT FROM AUTHOR]

OBJECTIVES: COVID-19 pandemic surges strained hospitals globally. We performed a systematic review to examine measures of pandemic caseload surge and its impact on mortality of hospitalized patients. DATA SOURCES: PubMed, Embase, and Web of Science. STUDY SELECTION: English-language studies published between December 1, 2019, and November 22, 2023, which reported the association between pandemic "surge"-related measures and mortality in hospitalized patients. DATA EXTRACTION: Three authors independently screened studies, extracted data, and assessed individual study risk of bias. We assessed measures of surge qualitatively across included studies. Given multidomain heterogeneity, we semi-quantitatively aggregated surge--mortality associations. DATA SYNTHESIS: Of 17,831 citations, we included 39 studies, 17 of which specifically described surge effects in ICU settings. The majority of studies were from high-income countries (n = 35 studies) and included patients with COVID-19 (n = 31). There were 37 different surge metrics which were mapped into four broad themes, incorporating caseloads either directly as unadjusted counts (n = 11), nested in occupancy (n = 14), including additional factors (e.g., resource needs, speed of occupancy; n = 10), or using indirect proxies (e.g., altered staffing ratios, alternative care settings; n = 4). Notwithstanding metric heterogeneity, 32 of 39 studies (82%) reported detrimental adjusted odds/hazard ratio for caseload surge--mortality outcomes, reporting point estimates of up to four-fold increased risk of mortality. This signal persisted among study subgroups categorized by publication year, patient types, clinical settings, and country income status. CONCLUSIONS: Pandemic caseload surge was associated with lower survival across most studies regardless of jurisdiction, timing, and population. Markedly variable surge strain measures precluded meta-analysis and findings have uncertain generalizability to lower-middle-income countries (LMICs). These findings underscore the need for establishing a consensus surge metric that is sensitive to capturing harms in everyday fluctuations and future pandemics and is scalable to LMICs. [ABSTRACT FROM AUTHOR]