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Objectives: The aims of this study were to assess the vortex characteristics of left ventricle (LV) in fetuses with coarctation of the aorta (CoA) using high–frame rate ultrasound with blood speckle‐tracking (BST) and explore its relationships with cardiac function and morphology parameters. Methods: Thirty fetuses with CoA and 30 gestational‐age matched normal fetuses were included in this cross‐sectional study. The area, length, width, and position of the vortex in the LV were recorded and quantitatively analyzed by BST echocardiography. The associations of vortex properties with ventricular function and morphology were also determined. Results: Based on BST imaging, the LV vortex can be observed in 93% of the fetuses. The fetuses with CoA exhibited significantly larger and wider vortex than the controls (P <.05). Linear regression analysis indicated that vortex area was positively related to sphericity index of LV as well as isovolumic relaxation time (r =.52, P =.003 and r =.42, P =.021). There was a negative correlation between vortex area and mitral valve size (r = −.443, P =.014). No significant association was found between vortex area and myocardial performance index and aortic isthmus size. Conclusions: It is feasible to quantitatively evaluate the left ventricular vortex in fetuses by BST. The fetuses with CoA exhibited greater vortex area and width, and the altered vortex property is associated with geometry of LV. This will facilitate our comprehension of the unique flow patterns and early cardiac remodeling in fetuses with CoA. [ABSTRACT FROM AUTHOR]

Soft clay is characterized by high compressibility, low permeability, low strength, and high water content, making it a poor substrate for construction. Hence, soil treatment is often required for soft clay. However, the traditional treatment methods, such as stacking and on-site mixing, involve large space, long time, and high cost. In contrast, lime is stable and cheap, but slow to set and harden. In this paper, the microbially induced carbonate precipitation (MICP) and lime composite curing of soft clay was investigated. Tests were carried out on soft clay samples with different lime ratios. By comparing the changes of strength, composition, and microstructure before and after curing, the mechanism of MICP/lime composite solidification of soft clay was systematically studied. The results showed that (1) a reasonable proportion of lime can react with water and CO2 in clay to generate CaCO3 , and also promote the induction of more CaCO3 precipitation by microorganisms, contributing to the improved strength of solidified clay; (2) MICP/lime composite curing can effectively reduce water in soft clay and help to improve the strength of solidified soil; (3) MICP and lime were complementary in terms of curing time, leading to continuous improvement of curing effect; and (4) the MICP/lime composite has a good effect on the solidification of soft clay. Under the experimental conditions in this study, the best solidification effect was observed for soft clay with a water content of 30% and a lime ratio of 30%. [ABSTRACT FROM AUTHOR]

In recent years, the nitrogen-vacancy (NV) center in diamonds has been demonstrated to be a high-performance multiphysics sensor, where a lock-in amplifier (LIA) is often adopted to monitor photoluminescence changes around the resonance. It is rather complex when multiple resonant points are utilized to realize a vector or temperature-magnetic joint sensing. In this article, we present a novel scheme to realize multipoint lock-in detection with only a single-channel device. This method is based on a direct digital synthesizer (DDS) and frequency-shift keying (FSK) technique, which is capable of freely hopping frequencies with a maximum of 1.4 GHz bandwidth and encoding an unlimited number of resonant points during the sensing process. We demonstrate this method in experiments and show it would be generally useful in quantum multi-frequency excitation applications, especially in the portable and highly mobile cases. [ABSTRACT FROM AUTHOR]

Low-cost bifunctional electrocatalysts capable of efficiently driving the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are needed for the growth of a green hydrogen economy. Herein, a Ru/Co 3 O 4 heterojunction catalyst rich in oxygen vacancies (V O ) and supported on carbon cloth (RCO-V O @CC) is prepared via a solid phase reaction (SPR) strategy. A RuO 2 /Co 9 S 8 @CC precursor (ROC@CC) is first prepared by loading Co 9 S 8 nanosheets onto CC, following the addition of RuO 2 nanoparticles (NPs). After the SPR process in an Ar atmosphere, Ru/Co 3 O 4 heterojunctions with abundant V O are formed on the CC. The compositionally optimized RCO-V O @CC electrocatalyst with a Ru content of 0.55 wt.% exhibits very low overpotential values of 11 and 253 mV at 10 mA cm -2 for HER and OER, respectively, in 1 m KOH. Further, a low cell voltage of only 1.49 V is required to achieve a current density of 10 mA cm -2 . Density functional theoretical calculations verify that the outstanding bifunctional electrocatalytic performance originates from synergistic charge transfer between Ru metal and V O -rich Co 3 O 4 . This work reports a novel approach toward a high-efficiency HER/OER electrocatalyst for energy storage and conversion., (© 2024 Wiley‐VCH GmbH.)

Stem cell spheroid is a promising graft substitute for bone tissue engineering. Spheroids obtained by 3D culture of STRO1+ Gingival Mesenchymal Stem Cells (sGMSCs) (sGMSC spheroids, GS) seldom express angiogenic factors, limiting their angiogenic differentiation in vivo . This study introduced a novel stem cell spheroid with osteogenic and angiogenic potential through 3D co-culture of sGMSCs and Human Umbilical Vein Endothelial Cells (HUVECs) (sGMSC/HUVEC spheroids, GHS). GHS with varying seeding ratios of sGMSCs to HUVECs (GHR) were developed. Cell fusion within the GHS system was observed via immunofluorescence. Calcein-AM/PI staining and chemiluminescence assay indicated cellular viability within the GHS. Furthermore, osteogenic and angiogenic markers, including ALP, OCN, RUNX2, CD31, and VEGFA, were quantified and compared with the control group comprising solely of sGMSCs (GS). Incorporating HUVECs into GHS extended cell viability and stability, initiated the expression of angiogenic factors CD31 and VEGFA, and upregulated the expression of osteogenic factors ALP, OCN, and RUNX2, especially when GHS with a GHR of 1:1. Taken together, GHS, derived from the 3D co-culture of sGMSCs and HUVECs, enhanced osteogenic and angiogenic capacities in vitro , extending the application of cell therapy in bone tissue engineering., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Liu, Chen, Zhou, Zeng, Liu, Wang, Xu, Yin and Rong.)

Purpose: This study evaluated the elastic characteristics of the pulmonary trunk and distal branches in fetuses diagnosed with tetralogy of Fallot (TOF) using Doppler echocardiography., Methods: Data on 42 fetuses diagnosed with TOF and 84 gestational age-matched normal fetuses were prospectively collected from the Second Xiangya Hospital of Central South University between August 2022 and January 2023. The severity of TOF was classified into three categories based on the z-score of the pulmonary annulus diameter: mild (z-score ≥-2), moderate (-40.05)., Conclusion: Fetuses diagnosed with TOF exhibited increased vascular stiffness in the MPA and reduced stiffness in the distal pulmonary artery (PA). Larger-scale follow-up studies are required to elucidate the relationships between these changes in vascular stiffness and PA development in patients with TOF.

Conventional hemostatic agents face challenges in achieving rapid hemostasis and effective tissue repair due to limited hemostatic scenarios, suboptimal efficacy, and inadequate adhesion to wet tissues. Drawing inspiration from nature-sourced materials, a gelatin-based adhesive hydrogel (AOT)  is designed, easily prepared and quick to form, driven by Schiff base and multiple hydrogen bonds for applications in arterial and liver bleeding models. AOT exhibits exceptional adhesion to wet tissues (48.67 ± 0.16 kPa) and displays superior hemostatic properties with reduced blood loss and hemostatic time compared to other hydrogels and conventional hemostatic materials. Moreover, AOT exhibits good biocompatibility and biodegradability. In summary, this easily prepared adhesive hydrogel has the potential to supplant traditional hemostatic agents, offering a novel approach to achieve swift sealing of hemostasis and facilitate wound healing and repair in broader application scenarios, owing to its unique advantages., (© 2024 Wiley‐VCH GmbH.)

The quest to decode the complex supraspinal mechanisms that integrate cutaneous thermal information in the central system is still ongoing. The dorsal horn of the spinal cord is the first hub that encodes thermal input which is then transmitted to brain regions via the spinothalamic and thalamocortical pathways. So far, our knowledge about the strength of the interplay between the brain regions during thermal processing is limited. To address this question, we imaged the brains of adult awake male mice in resting state using functional ultrasound imaging during plantar exposure to constant and varying temperatures. Our study reveals for the first time the following: (1) a dichotomy in the response of the somatomotor-cingulate cortices and the hypothalamus, which was never described before, due to the lack of appropriate tools to study such regions with both good spatial and temporal resolutions. (2) We infer that cingulate areas may be involved in the affective responses to temperature changes. (3) Colder temperatures (ramped down) reinforce the disconnection between the somatomotor-cingulate and hypothalamus networks. (4) Finally, we also confirm the existence in the mouse brain of a brain mode characterized by low cognitive strength present more frequently at resting neutral temperature. The present study points toward the existence of a common hub between somatomotor and cingulate regions, whereas hypothalamus functions are related to a secondary network., (Copyright © 2024 Koorliyil et al.)