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Soil acidification caused by acid deposition and N fertilization can significantly affect the composition and activity of microbial communities in acidic soils. However, whether and how acidification affects soil microorganisms and microbial‐mediated carbon (C) dynamics in alkaline soils are less known. Based on a 7‐year (2016–2023) acid addition experiment in an alkaline grassland (pH > 8) on the Loess Plateau in Northwest China, we examined the effects of soil acidification on soil fungal and bacterial communities and their C metabolism. Unexpectedly, our results showed that soil acidification mainly reduced fungal diversity, rather than bacterial diversity, possibly because acidification led to soil NH4+ accumulation and decreased plant diversity. Also, soil acidification reduced forb but increased grass biomass, and enhanced root production and turnover rate. Laboratory incubation experiments showed that changes in the microbial community and soil properties jointly promoted microbial decomposition of soil organic C (SOC), with more promotion for the decomposition of labile C (i.e. glucose) (+68.4%) than recalcitrant C (i.e. tannin) (+29.1%). Synthesis. Soil acidification reduced fungal diversity and stimulated SOC decomposition in an alkaline grassland. Given that pH decline can also accelerate soil inorganic C dissolution and carbonate‐derived CO2 release, these results highlight that soil acidification can exacerbate C loss in the alkaline soils over the long term. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Biodegradable vascular stents (BVS) are deemed as great potential alternatives for overcoming the inherent limitations of permanent metallic stents in the treatment of coronary artery diseases. The current study aimed to comprehensively compare the mechanical behaviors of four poly(lactic acid) (PLA) BVS designs with varying geometries via numerical methods and to clarify the optimal BVS selection. Four PLA BVS (i.e., Absorb, DESolve, Igaki-Tamai, and Fantom) were first constructed. A degradation model was refined by simply including the fatigue effect induced by pulsatile blood pressures, and an explicit solver was employed to simulate the crimping and degradation behaviors of the four PLA BVS. The degradation dynamics here were characterized by four indices. The results indicated that the stent designs affected crimping and degradation behaviors. Compared to the other three stents, the DESolve stent had the greatest radial stiffness in the crimping simulation and the best diameter maintenance ability despite its faster degradation; moreover, the stent was considered to perform better according to a pilot scoring system. The current work provides a theoretical method for studying and understanding the degradation dynamics of the PLA BVS, and it could be helpful for the design of next-generation BVS. [ABSTRACT FROM AUTHOR]

Optogenetic control of the heart is an emergent technology that offers unparalleled spatio-temporal control of cardiac dynamics via light-sensitive ion pumps and channels (opsins). This fast-evolving technique holds broad scope in both clinical and basic research setting. Combination of optogenetics with optical mapping of voltage or calcium fluorescent probes facilitates 'all-optical' electrophysiology, allowing precise optogenetic actuation of cardiac tissue with high spatio-temporal resolution imaging of action potential and calcium transient morphology and conduction patterns. In this review, we provide a synopsis of optogenetics and discuss in detail its use and compatibility with optical interrogation of cardiac electrophysiology. We briefly discuss the benefits of all-optical cardiac control and electrophysiological interrogation compared to traditional techniques, and describe mechanisms, unique features and limitations of optically induced cardiac control. In particular, we focus on state-of-the-art setup design, challenges in light delivery and filtering, and compatibility of opsins with fluorescent reporters used in optical mapping. The interaction of cardiac tissue with light, and physical and computational approaches to overcome the 'spectral congestion' that arises from the combination of optogenetics and optical mapping are discussed. Finally, we summarize recent preclinical work applications of combined cardiac optogenetics and optical mapping approach. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) bead foams with stereocomplex (Sc)/α crystals were prepared by melt mixing and solid‐state foaming methods, independently. A systematic method was applied to evaluate the effect of Sc/α crystals on rheological properties and foaming behavior of PLA. The results indicated that the presence of Sc/α crystals affected the foaming behavior and the melt elasticity of PLA. Hence, the enhanced rheological properties of PLA had a significant effect on controlling the foaming behavior. As a result, PLA bead foam with an expansion ratio of 24‐fold was developed. And, the presence of Sc/α crystals could also facilitate the sintering behavior and broaden the sintering process window. Sintered PLA bead foam with finer cellular morphology and strong sintering effect was obtained by inducing an appropriate Sc/α crystalline structure. © 2018 Society of Chemical Industry Sintered PLA bead foam with fine cellular morphology and strong sintering effect was obtained by inducing an appropriate Sc/α crystalline structure. [ABSTRACT FROM AUTHOR]

High-performance poly(lactic acid) (PLA) foam has been recognized as a promising material because of its biodegradability. However, low flexibility and foamability of PLAs has limited its use in different fields. In this study, a blend-toughening technology was used to toughen PLA and prepare flexible foams. The mechanical properties of PLA blends were evaluated, and the cellular structure of these foaming blends was characterized. The results show that the blending components significantly affected the overall mechanical properties and foaming behavior of PLA. The toughness of PLA was enhanced by adding poly(butylene adipate-co-terephthalate) (PBAT) and rigid particles. The rheological behavior of PLA was also affected by adding PBAT. Therefore, the cellular structure of the PLA foams was affected. A constitutive model was also used to fit the experimental results of the compression property of the PLA foam. [ABSTRACT FROM AUTHOR]

Climatic warming can alter grassland nitrous oxide (N 2 O) emissions due to soil property alterations. However, how the reclamation affect grassland N 2 O flux under warming conditions remains unclear in alpine meadow ecosystems. We conducted a long-term manipulative warming experiment in a natural alpine meadow and a cultivated grassland on the Qinghai-Tibetan Plateau to explore the separate and interactive effects of warming and reclamation on the soil N 2 O emission flux. N 2 O fluxes were measured under four treatments including control (CK), warming (W), reclamation (R) and warming under reclamation (WR) from August 2018 to July 2019. We measured the content of soil C, N nutrients and 5 enzymatic activities in 2018 and 2019. Correlation analysis and structural equation modeling were used to clarify how soil N availability and soil enzyme activities affect N 2 O emission. Our results indicated that compared to the ambient conditions for the growing and non-growing seasons, soil N 2 O flux was significantly increased 59.1% and 152.0% by warming and 28.4% and 142.4% by reclamation, respectively. Compared with W, WR significantly increased N 2 O flux by 18.9% and 81.1% during the growing and non-growing seasons, respectively. Soil moisture was negatively correlated to enzymatic activity and N 2 O flux. Both warming and reclamation promoted soil nitrification by increasing related enzymatic activities that acted to increase the N 2 O flux. Reclamation resulted in a greater sensitivity of the activity of ammonia monooxygenase and hydroxylamine oxidoreductase to warming, thus enhancing the effects of warming on increasing the N 2 O flux. Our research indicated that reclamation can additionally increase the effects of warming on N 2 O emissions for alpine meadows. Therefore, excessive expansion of arable land should be avoided, and new reclamation sites should be planned scientifically, as warming is expected to intensify in the future., 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 © 2023 Li, Li, Hu, Wu, Liang, Yan, He, Ganjurjav and Gao.)

Objective: To evaluate the clinical efficacy and radiological changes in patients with painful osteoporotic vertebral compression fractures (OVCFs) after percutaneous vertebroplasty (PVP)., Methods: Retrospective analysis was conducted on 195 vertebrae in 142 patients with painful OVCFs treated with vertebroplasty in our hospital from May 2007 to June 2012. The scores of visual analogue scale (VAS) were recorded and the heights of vertebral bodies and Cobb angles were measured in the mid-sagittal plane of the reformatted images at 64-detector row CT during the period of follow-up. Polymethylmethacrylate (PMMA) distribution in vertebrae and whether leakage was observed on CT within 3 days after PVP. The changes in VAS, heights of vertebral bodies and Cobb angles were compared between the cases with and without leakages., Results: The successful rate of technique of PVP was 100%. The mean volume of PMMA injected in each vertebra was (4.5 ± 1.1) ml and (6.0 ± 1.2) ml respectively in thoracic and lumbar. The mean follow-up was (17 ± 6) months. Asymptomatic leakages of PMMA were demonstrated by CT in 38 patients with 43 vertebrae (22.1%). The average decrease in VAS was 5.25 and 1.12 respectively in 24 hours and a month after PVP. The changes in VAS respectively at 1 month, 3 months, 6 months and more than 1 year after procedure were not significantly different.In postoperative 3 days, the average increase in height of vertebral body was 1.55 mm anteriorly and 1.38 mm centrally, the average reduction in Cobb angle were 2.37°. The heights and Cobb angles of vertebral bodies between in 3 days and in more than 1 year after PVP were not significantly different. The scores of VAS and the changes in vertebral body heights and Cobb angles between the patients with or without cement leakages were not significantly different during the period of follow-up., Conclusion: PVP is an effective treatment for patients with painful OVCFs that provides immediate and sustained pain relief, increases in the heights of vertebral bodies injected in cement and keeps stable radiological progression within at least 1 year after PVP. Asymptomatic cement leakages around vertebrae have no influence on pain relief and vertebral stability in this group of patients.