Extracting gold from wastes of electronic equipment (e-waste) is a sustainable strategy for the recovery of the precious metal, reducing environmental pollution, and addressing the growing demands for gold resources. In this work, we synthesized a thiourea-modified porous aromatic framework (PAF-1-thiourea) with exceptional gold-extraction ability. The optimum adsorption capacity for PAF-1-thiourea to gold reaches up to 2629.87 mg g-1. The adsorption process can be well fitted according to the pseudo-second-order kinetic model and Langmuir model, featuring strong affinity caused by strong soft-soft interactions between Au(III) and the S and N donor atoms of the modified PAF and the electrostatic interactions between protonated amino groups and AuCl4-. PAF-1-thiourea was especially capable of extracting gold rapidly and efficiently (capturing 98.73% of gold within 5 min) from a central processing unit (CPU) in extremely acidic conditions. It is found that PAF-1-thiourea captures gold ions and simultaneously converts it to a Au(0) solid, obtaining gold with purity up to 23.5 karat. PAF-1-thiourea with its high acid resistance and anti-interference against cheap metals in the recovery process presents a practical means to extract gold from e-waste.
Soil salinity has become a major stress factor that reduces crop productivity worldwide. Sodium (Na+) toxicity in a number of crop plants is tightly linked with shoot Na+ overaccumulation, thus Na+ exclusion from shoot is crucial for salt tolerance in crops. In this study, we identified a member of the high-affinity K+ transport family (HAK), OsHAK12, which mediates shoots Na+ exclusion in response to salt stress in rice. The Oshak12 mutants showed sensitivity to salt toxicity and accumulated more Na+ in the xylem sap, leading to excessive Na+ in the shoots and less Na+ in the roots. Unlike typical HAK family transporters that transport K+, OsHAK12 is a Na+-permeable plasma membrane transporter. In addition, OsHAK12 was strongly expressed in the root vascular tissues and induced by salt stress. These findings indicate that OsHAK12 mediates Na+ exclusion from shoot, possibly by retrieving Na+ from xylem vessel thereby reducing Na+ content in the shoots. These findings provide a unique function of a rice HAK family member and provide a potential target gene for improving salt tolerance of rice.
The effect of high Cu2+ stress on fermentation performance and copper biosorption of Saccharomyces cerevisiae BH8 during wine fermentation was investigated in this paper. Under high Cu2+ stress, the cell growth and survival rate of yeast BH8 were inhibited. With different copper concentration, the effect on cell growth of yeast BH8 was different. What's more, high Cu2+ stress could inhibit the fermentation property, alcohol production and reducing sugar utilization of yeast BH8 in Chardonnay grape must, but not significant. And the trend of the copper ion concentration falling down was consistent with the trend of yeast growth rising up, meanwhile the copper content was still much less than the initial concentration after fermentation. In addition, yeast BH8 showed a good fermenting property and copper removal ability under high Cu2+ stress. These results could provide certain reference and some new data for the wine industry to face the copper pollution risk.
Proanthocyanidins (PAs) are important secondary metabolites crucial for the quality of grape berry and wine. Despite important advances in our understanding of the structural and regulatory genes involved in the PAs biosynthesis pathway, our knowledge about the details of biosynthetic and regulatory networks, especially the mechanism of polymerization and transportation remains limited. We provided an overview of the latest discoveries related to the mechanisms of grape PAs structure, astringency properties, detection methods, biosynthesis and transportation. We also summarized the environmental influencing factors of PAs synthesis in grape. Future trends were discussed.
We consider a stochastic one‐predator‐two‐prey harvesting model with time delays and Lévy jumps in this paper. Using the comparison theorem of stochastic differential equations and asymptotic approaches, sufficient conditions for persistence in mean and extinction of three species are derived. By analyzing the asymptotic invariant distribution, we study the variation of the persistent level of a population. Then we obtain the conditions of global attractivity and stability in distribution. Furthermore, making use of Hessian matrix method and optimal harvesting theory of differential equations, the explicit forms of optimal harvesting effort and maximum expectation of sustainable yield are obtained. Some numerical simulations are given to illustrate the theoretical results.
We propose a score-based DAG structure learning method for time-series data that captures linear, nonlinear, lagged and instantaneous relations among variables while ensuring acyclicity throughout the entire graph. The proposed method extends nonparametric NOTEARS, a recent continuous optimization approach for learning nonparametric instantaneous DAGs. The proposed method is faster than constraint-based methods using nonlinear conditional independence tests. We also promote the use of optimization constraints to incorporate prior knowledge into the structure learning process. A broad set of experiments with simulated data demonstrates that the proposed method discovers better DAG structures than several recent comparison methods. We also evaluate the proposed method on complex real-world data acquired from NHL ice hockey games containing a mixture of continuous and discrete variables. The code is available at this https URL.
Xylanase inhibitors have been confirmed to be involved in plant defence. OsXIP is a XIP-type rice xylanase inhibitor, yet its transcriptional regulation remains unknown. Herbivore infestation, wounding and methyl jasmonate (MeJA) treatment enhanced mRNA levels and protein levels of OsXIP. By analyzing different 5' deletion mutants of OsXIP promoter exposed to rice brown planthopper Nilaparvata lugens stress, a 562 bp region (–1451 – −889) was finally identified as the key sequence for the herbivores stress response. Using yeast one-hybrid screening, coupled with chromatin immunoprecipitation analysis, a basic helix-loop-helix protein (OsbHLH59) and an APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor OsERF71 directly binding to the 562 bp key sequence to activate the expression of OsXIP were identified, which is further supported by transient expression assay. Moreover, transcriptional analysis revealed that mechanical wounding and treatment with MeJA resulted in an obvious increase in transcript levels of OsbHLH59 and OsERF71 in root and shoot tissues. Our data shows that two proteins as direct transcriptional activators of OsXIP responding to stress were identified. These results reveal a coordinated regulatory mechanism of OsXIP, which may probably be involved in defence responses via a JA-mediated signaling pathway.
: The effects of ultrasound (US), thermosonication (TS), ultrasound combined with nisin (USN), TS combined with nisin (TSN), and conventional thermal sterilization (CTS) treatments on the inactivation of microorganisms in grape juice were evaluated. TS, TSN, and CTS treatments provided the desirable bactericidal and enzyme inactivation, and nisin had a synergistic lethal effect on aerobic bacteria in grape juice while not having any obvious effect on the mold and yeast. Compared with CTS, the sensory characteristics of grape juice treated with TS and TSN are closer to that of fresh juice, its microbial safety is ensured, and the physicochemical properties are basically unchanged. More importantly, the total phenolic content and antioxidant capacity of juice treated with TS and TSN were significantly increased, and the total anthocyanin and flavonoid contents were largely retained. Taken together, these findings suggest that TS and TSN has great potential application value and that it can ensure microbial safety and improve the quality of grape juice.
A Mn–Ni–Co–O ternary metal oxide with a unique 3D microstructure shows high electrocatalytic activity and stability towards methanol electrooxidation.
To observe the clinical outcomes of a combined unilateral intraoral and extraoral reduction approach in the treatment of anterior temporomandibular joint (TMJ) dislocation.Postural muscular chains were utilized in the biomechanical analysis of stomatognathic systems for improving TMJ repositioning approaches. A total of 87 patients with anterior TMJ dislocation were included in the present study. A combined unilateral intraoral and extraoral reduction approach was applied, and the clinical effects were evaluated.Biomechanical analysis reveal that reflexive contrac-tion of the maxillary muscle group was blocked sufficiently during the combined unilateral intraoral and extraoral reduction process. All dislocated TMJs were set successfully and efficiently with few complications.Combined unilateral intraoral and extraoral reduction approach is an effective, convenient, and minimally invasive way to treat anterior TMJ dislo-cations.目的 探讨分侧口内外联合法治疗颞下颌关节前脱位的临床效果。方法 利用口颌系统姿态肌链平衡理论对颞下颌关节复位过程进行生物力学分析,改进复位手法;运用分侧口内外联合法治疗87例颞下颌关节前脱位患者,对临床效果进行评价。结果 分侧口内外联合法可有效避免升颌肌群反射性收缩,提高复位效率;87例患者均成功复位,术程用力轻巧高效,髁突下降指征明确,患者并发症少。结论 分侧口内外联合法是一种高效、便捷、微创的颞下颌关节前脱位复位方法,在临床上有一定的推广应用价值。.