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Seed vigor is a complex trait encompassing seed germination, seedling emergence, growth, seed longevity, and stress tolerance, all are crucial for direct seeding in rice. Here, we report that the AP2/ERF transcription factor OsRAV1 (RELATED TO ABI3 AND VP1) positively regulates seed germination, vigor, and salt tolerance. Additionally, OsRAV1 was differently expressed in embryo and endosperm, with the OsRAV1 localized in the nucleus. Transcriptomic analysis revealed that OsRAV1 modulates seed vigor through plant hormone signal transduction and phenylpropanoid biosynthesis during germination. Haplotype analysis showed that rice varieties carrying Hap3 displayed enhanced salt tolerance during seed germination. These findings suggest that OsRAV1 is a potential target in breeding rice varieties with high seed vigor suitable for direct seeding cultivation. [ABSTRACT FROM AUTHOR]

In order to ensure the filling integrity of complex counter-gravity casting and improve metallurgical quality, it is necessary to shorten the filling time while avoiding air entrainments. To address this contradiction, a novel nonlinear pressurization method was proposed in this study. Through systematically analyzing the relationship between critical gating velocity and stable filling height, a criterion for iterative calculation of nonlinear pressurization curve was established, and an empirical expression between nonlinear pressurizing speed and the filling height was obtained. Based on the empirical expression, a nonlinear pressurization curve can be designed according to the casting structures and initial pressurizing speeds. The above nonlinear pressure curve design method was validated through water filling experiments. It was proved that the nonlinear pressure curve can shorten the filling time while avoiding air entrainments. It provides important processing control method for improving the low-pressure casting performance of complex castings. [ABSTRACT FROM AUTHOR]

Ceramic capacitors are receiving increasing interest because of their applications in pulsed-power devices. The perovskite oxide Bi0.5Na0.5TiO3 (BNT)-based ferroelectric ceramics are regarded as prospective lead-free candidate for dielectric capacitors because of the high polarization and outstanding relaxor behaviour. Herein, the relaxor ferroelectric (0.7−x)Bi0.5Na0.5TiO3–0.3SrTiO3–xCa0.7Sm0.2TiO3 ceramics synthesized through solid-state route and exhibited pseudocubic perovskite structure and strong relaxor behaviour. With increasing Ca0.7Sm0.2TiO3 content, the moderate permittivity and reduced grain size contributed to the monotonically increased electric breakdown strength. Among prepared samples, the x = 0.2 ceramic displayed slimmer polarization-electric field curves with a remarkable recoverable energy density (~6.8 J/cm3) and a satisfied efficiency (~82.2%) under external electric field of 450 kV/cm. Moreover, the x = 0.2 ceramic also exhibited a superb thermal reliability of energy storage properties (3.9–4.5 J/cm3 with variation of 13.3% in 25–160 °C) resulting from the diffuse phase transition. The above results make the x = 0.2 ceramics becoming promising candidates for pulsed-power devices. [ABSTRACT FROM AUTHOR]

Ultrasound is an acoustic wave which can noninvasively penetrate the skull to deep brain regions, enabling neuromodulation. However, conventional ultrasound's spatial resolution is diffraction-limited and low-precision. Here, we report acoustic nanobubble-mediated ultrasound stimulation capable of localizing ultrasound's effects to only the desired brain region in male mice. By varying the delivery site of nanobubbles, ultrasound could activate specific regions of the mouse motor cortex, evoking EMG signaling and limb movement, and could also, separately, activate one of two nearby deep brain regions to elicit distinct behaviors (freezing or rotation). Sonicated neurons displayed reversible, low-latency calcium responses and increased c-Fos expression in the sub-millimeter-scale region with nanobubbles present. Ultrasound stimulation of the relevant region also modified depression-like behavior in a mouse model. We also provide evidence of a role for mechanosensitive ion channels. Altogether, our treatment scheme allows spatially-targetable, repeatable and temporally-precise activation of deep brain circuits for neuromodulation without needing genetic modification. Ultrasound may be used to non-invasively modulate the brain. Here the authors describe acoustic nanobubble-mediated ultrasound stimulation of specific brain region in male mice. [ABSTRACT FROM AUTHOR]

Based on the ERA5 reanalysis dataset, we analyzed the changes in extreme climate indices on the MP from 1981 to 2020, and the relationship between the extreme climate indices and atmospheric circulation indices. The results showed that (1) for temperature, (a) in terms of hot events, the inter-annual variation trends of summer days, warm days, and warm nights have significantly increased across the entire MP, with the central region experiencing a higher probability of extreme hot events. The inter-decadal variation of extreme hot indices showed a considerable increase from the period of 1991 to 2000 to the period of 2001 to 2010. (b) In terms of cold events, a substantial decrease in extreme cold events was revealed, with a great decrease from the period of 1981 to 1990 to the period of 1991 to 2000. (2) For precipitation, there was a decrease in extreme wet indices from 1981 to 2020. The simple precipitation intensity index (SDII) and total precipitation in wet days (PRCPTOT) exhibited a significant descending trend in the northern and northeastern MP. Decadal variations showed a decrease in extreme precipitation events, with a significant decline observed between the period of 1991 to 2000 and the period of 2001 to 2010. (3) For the relationship between the extreme climate indices and atmospheric circulation indices, extreme temperature indices are likely influenced by polar vortices, with the Asian polar vortex area index (APVAI) negatively correlated with extreme hot indices and the Asian polar vortex intensity index (APVII) positively/negatively correlated with most extreme hot and cold indices. Asian zonal circulation index (AZCI) showed significant correlations with most extreme hot and cold indices. Extreme precipitation indices only showed significant negative correlations with the Atlantic Meridional mode (AMM). [ABSTRACT FROM AUTHOR]

In recent years, the prevalence of allergic diseases has increased significantly, causing great concern, and wheat, as one of the top 8 food allergens, is a common allergy trigger. Nevertheless, reliable estimates of the positivity rate of wheat allergens in the allergic population in China are still lacking. The systematic review and meta-analysis aims to evaluate the positive detection rate of wheat allergens in the Chinese allergic population and further provide a reference for the prevention of allergy. CNKI, CQVIP, WAN-FANG DATA, Sino Med, PubMed, Web of Science, Cochrane Library, and Embase databases were retrieved. Related research and case reports about the positive rate of wheat allergen in the Chinese allergic population published from inception to June 30, 2022, were searched, and meta-analysis was performed using Stata software. The pooled positive rate of wheat allergens and 95% confidence interval were calculated by random effect models, and the publication bias was evaluated using Egger's test. A total of 13 articles were included for the final meta-analysis, in which wheat allergen detection methods involved only serum sIgE testing and SPT assessment. The results showed that the wheat allergen positivity detection rate in Chinese allergic patients was 7.30% (95% CI 5.68–8.92%). Subgroup analysis showed that the positivity rate of wheat allergens was influenced by region, but hardly by age and assessment method. The positive rates of wheat allergy in the population with allergic diseases were 2.74% (95% CI 0.90–4.58%) and 11.47% (95% CI 7.08–15.87%) in southern and northern China, respectively. In particular, the positive rates of wheat allergens were greater than 10% in Shaanxi, Henan and Nei Mongol, all of which belong to the northern region. These results suggest that wheat allergens are an important cause of sensitization in allergic populations from northern China, and therefore attention should be paid to early prevention in high-risk populations. [ABSTRACT FROM AUTHOR]

Objectives: To identify whether parameters measured from diffusion kurtosis and intravoxel incoherent motion help diagnose placenta percreta. Methods: We retrospectively enrolled 75 patients with PAS disorders including 13 patients with placenta percreta and 40 patients without PAS disorders. Each patients underwent diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI). The apparent diffusion coefficient (ADC), perfusion fraction (f), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), mean diffusion kurtosis (MK) and mean diffusion coefficient (MD) were measured by the volumetric analysis and compared. MRI features were also analyzed and compared. The receiver operating characteristic (ROC) curve and logistic regression analysis were used to evaluate the diagnostic efficiency of different diffusion parameters and MRI features for distinguishing placental percreta. Results: D* was an independent risk factor from DWI for predicting placenta percreta with sensitivity of 73% and specificity of 76%. Focal exophytic mass remained as independent risk factor from MRI features for predicting placenta percreta with sensitivity of 72.7% and specificity of 88.1%. When the two risk factors were combined together, the AUC was the highest, 0.880 (95% CI 0.8–0.96). Conclusion: D* and focal exophytic mass were associated with placenta percreta. A combination of the 2 risk factors can be used to predict placenta percreta. Critical relevance statement: A combination of D* and focal exophytic mass can be used to differentiate placenta percreta. Key points: D* and focal exophytic mass were associated with placenta percreta. DWI parameters help quantify PAS. Placenta percreta can be differentiated with combination of risk factors. [ABSTRACT FROM AUTHOR]

Photochemical vapor generation (PVG) of germanium (Ge) was first reported in this work. The synergistic effect from cobalt/chloride ions and air-liquid interfaces was found for the PVG of Ge. No obvious signal response was observed from the standard solution of Ge in 10% (v/v) formic acids (FAs) under UV irradiation. The addition of 300 mg L−1 of Co2+ and 30 mmol L−1 of Cl− resulted in enhanced photochemical reduction for Ge, and the introduction of air-liquid interfaces proceeding and succeeding the sample solution caused another 4.6 folds of enhancement in signal response of Ge. Under the selected condition, the limit of detection (LOD, 3σ, n = 11) was obtained to be 0.008 ng mL−1 with inductively coupled plasma mass spectrometry (ICP MS) measurement. A good precision, expressed as a relative standard deviation (RSD, n = 7) of 2.0%, was found from replicated measurements of 2 ng mL−1 of Ge. The generation efficiency was found to be no better than 9 ± 2%. The PVG mechanism of Ge was investigated in this work. The new finding is useful for understanding the principle of PVG, and further exploring the analytical and environmental application of PVG. [ABSTRACT FROM AUTHOR]

Based on the precipitation records of 2474 meteorological stations, this study investigated precipitation characteristics and trends in China from 1961 to 2010, including spatiotemporal distribution and changes in average annual precipitation amount, number of days when daily precipitation > = 1, 5, 10, 25, 50 mm, and extreme precipitation indices. The results showed that: (1) in terms of annual average precipitation amount, both dry to wet, wet to wetter, and shifting between wet and dry showed decadal and climatical fluctuations in annual precipitation totals in space and time, with a clear shift in space from the 0 to 200 mm and above 400 mm precipitation levels to the 200 to 400 mm precipitation level. (2) In terms of graded precipitation days, three kinds of trend changes were observed: (a) enhancement, manifested as an increase in precipitation events, mainly in the northwest and northeast of China; (b) reduction, manifested as a decrease in precipitation events, mainly in the central parts of China; and (c) polarization, which is manifested as a decrease in gentle and light precipitation events but an increase in dry days, heavy, and rainstorm precipitation events, primarily along coastal area in southeast China. (3) In terms of extreme precipitation events, precipitation persistence showed a decreasing trend, but an increasing trend in precipitation intensity and magnitude in most regions of China. This paper also presents the relationship between certain atmospheric circulation indices and the seasonal precipitation of summer and winter. The distribution characteristics and changes in minor precipitation events were highlighted, including gentle and light rain events. Relevant findings can provide scientific guidance for water resource management and conservation. [ABSTRACT FROM AUTHOR]