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The resource recovery and reuse of precious metal-laden wastewater is widely recognized as crucial for sustainable development. Superalloy electrolytes, produced through the electrolysis of superalloy scrap, contain significant quantities of precious metal ions, thereby possessing substantial potential for recovery value. This study first explores the feasibility of utilizing fungi to treat Superalloy electrolytes. Five fungi resistant to high concentrations of heavy metals in electrolytes (mainly containing Co, Cr, Mo, Re, and Ni) were screened from the soil of a mining area to evaluate their adsorption characteristics. All five fungi were identified by ITS sequencing, and among them, Paecilomyces lilacinus showed the best adsorption performance for the five heavy metals; therefore, we conducted further research on its adsorption characteristics. The best adsorption effect of Co, Cr, Mo, Re, and Ni was 37.09, 64.41, 47.87, 41.59, and 25.38%, respectively, under the conditions of pH 5, time 1 h, dosage 26.67 g/L, temperature 25-30°C, and an initial metal concentration that was diluted fivefold in the electrolyte. The biosorption of Co, Mo, Re, and Ni was better matched by the Langmuir model than by the Freundlich model, while Cr displayed the opposite pattern, showing that the adsorption process of P. lilacinus for the five heavy metals is not a single adsorption mechanism, but may involve a multi-step adsorption process. The kinetics study showed that the quasi-second-order model fitted better than the quasi-first-order model, indicating that chemical adsorption was the main adsorption process of the five heavy metals in P. lilacinus. Fourier transform infrared spectroscopy revealed that the relevant active groups, i.e., hydroxyl (-OH), amino (-NH2), amide (- CONH2), carbonyl (-C = O), carboxyl (-COOH), and phosphate (PO43-), participated in the adsorption process. This study emphasized the potential application of P. lilacinus in the treatment of industrial wastewater with extremely complex background values.

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Fruit cracking affects both the yield and economic efficiency of citrus; however, the underlying mechanism remains unclear. Therefore, this study focused on resistant and susceptible cultivars to identify the mechanisms underlying fruit cracking. The results showed that in 'Mingrijian', pectin morphological transformation and hemicellulose and lignin degradation in the pericarp were important contributing factors. During the critical fruit-cracking period (115-150 days after flowering), the water-soluble pectin, protopectin, and lignin contents in the pericarp of 'Daya' presented inverse changes relative to those in 'Mingrijian', thus enhancing the mechanical properties and resistance of pericarp. From 115 to 150 days after flowering, the soluble sugar content in the pulp of 'Mingrijian' increased rapidly by 97.35%, aiding in pulp water absorption and expansion. Moreover, the soluble protein content in the pericarp of 'Mingrijian' exhibited a declining trend and was lower than that of 'Daya', thus affecting the overall metabolism. The superoxide dismutase (SOD) activity in the pericarp of 'Mingrijian' gradually decreased from 115 to 180 days after flowering, while the peroxidase (POD) activity remained at a low level, resulting in weaker antioxidant capacity and lower environmental resistance. This study provides valuable insights into the mechanisms of citrus fruit cracking, laying the foundation for preventive and control strategies.

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Freshwater lake eutrophication is a global concern causing adverse effects on aquatic ecosystems. The degradation of lake aquatic-terrestrial ecotones, which are the transitional zones between terrestrial and water ecosystems, contributes to eutrophication. These ecotones play vital roles in nutrient cycling, runoff control, biodiversity conservation, and habitat provision. In the past three decades, the research on lake aquatic-terrestrial ecotones has focused on techniques for managing contaminants and runoff purification. This paper reviews the recent studies on the restoration ability of eutrophic water bodies in lake aquatic-terrestrial ecotones in recent years regarding three aspects: the establishment, restoration mechanism, and improvement of restoration function. In addition, ecological factors such as lakeshore height, water level, surface runoff, shallow groundwater level, and rainfall intensity have impacts on the restoration capacity of lake aquatic-terrestrial ecotones.

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Interstock is an important agronomic technique for regulating plant growth and fruit quality, and overcoming the incompatibility between rootstocks and scions; however, the underlying mechanisms remain largely unknown. In this study, the effects and regulatory mechanisms of tangor grafting, with and without interstocks, on the growth and development of scions were analyzed by combining morphology, physiology, anatomy and transcriptomics. Morphological and physiological analyses showed that interstocks ('Aiyuan 38' and 'Daya') significantly improved the growth of seedlings, effectively enhanced the foliar accumulation of chlorophyll and carotenoids, and increased the thickness of leaf tissues. Using 'Aiyuan 38' as the interstock, photosynthetic efficiency and starch content of citrus seedlings improved. Transcriptomics showed that genes related to photosynthesis and photosynthetic antenna proteins were upregulated in interstock-treated seedlings, with significant upregulation of photosystem PSI- and PSII-related genes. In addition, multiple key genes may be involved in plant hormone signaling, starch and sucrose metabolism, and transcriptional regulation. Taken together, these findings provide novel insights into the role of interstocks in regulating and contributing to the growth and development of grafted seedlings, and will further define and deploy candidate genes to explore the mechanisms of rootstock-interstock-scion interactions.

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Harumi tangor fruit with Ponkan as an interstock contains significantly higher levels of total soluble solids compared to Harumi tangor fruit cv.with no interstock. Transcriptome analysis of two graft combinations (Harumi/Hongjv (HP) and cv. cv.Harumi/Ponkan/Hongjv (HPP)) was conducted to identify the genes related to use of the Ponkan interstock. Soluble sugars and organic acids were also measured in the two graft combinations. The results showed that the contents of sucrose, glucose, and fructose were higher in the fruits of HPP than in those of HP; additionally, the titratable acid levels were lower in grafts with interstocks than in grafts without interstocks. Transcriptome analysis of HPP and HP citrus revealed that the interstock regulated auxin and ethylene signals, sugar and energy metabolism, and cell wall metabolism. Trend and Venn analyses suggested that genes related to carbohydrate-, energy-, and hormone-metabolic activities were more abundant in HPP plants than in HP plants during different periods. Moreover, weighted gene co-expression network analysis demonstrated that carbohydrates, hormones, cell wall, and transcription factors may be critical for interstock-mediated citrus fruit development and ripening. The contents of ethylene, auxin, cytokinin, transcription factors, starch, sucrose, glucose, fructose, and total sugar in HPP plants differed considerably than those in HP fruits. Interstocks may help to regulate the early ripening and quality of citrus fruit through the above-mentioned pathways. These findings provide information on the effects of interstock on plant growth and development.

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The price jump behavior may bring tremendous challenges on risk management and asset pricing. This paper uses the BN-S test, the wavelet coherence method, and applies high-frequency data to explore whether and to what extent the COVID-19 pandemic impacts China's energy stock market jumps and its characteristics. The empirical results uncover the significant and heterogeneous interactions between the COVID-19 pandemic and China's energy stock market jumps across market specifications, investment horizons, and China/global pandemic tolls at different time scales. First, the oil stock market jumps were the most correlated with the pandemic, especially during the peak and re-deterioration phases. The pandemic played a positive and leading role in the short term (1-4 days length period) and long term (over 32 days length period). Second, the coal stock market jumps have similar characteristics to those of oil, but mainly show a negative correlation with the pandemic. Third, renewable energy stock market jumps were the least correlated, mainly showing a positive correlation in the short term and a negative correlation in the long term. In addition, the interaction characteristics of systemic co-jumps in different China's energy stock markets are also significant.

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The nutritional status of rural Chinese children has improved in recent years, but their nutritional knowledge is still relatively lacking. School-based nutrition and health education was conducted for children in three counties of China from 2018 to 2020. The students in the intervention schools were given two-year nutrition and health education courses, while the control schools did not receive any intervention. Students' nutrition knowledge, dietary intake, and dietary behaviors were collected using a questionnaire, and height and weight were measured uniformly. The nutrition knowledge score in the intervention group was increased by 1.01 and 0.64 points in the first and second years. A multilevel model was used to evaluate the intervention effects. Statistically significant interactions between groups and time were observed in nutrition knowledge, the frequency of eating breakfast, and dietary intake, including meat, eggs, milk, and vegetables (p < 0.05), but not in nutritional status. Therefore, the supplementation of school-based nutrition and health education had a positive impact on the nutrition knowledge and dietary intake of rural Chinese children.

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In late-developing regions, new technologies and previous experiences are applied to reduce the impact of economic development on environmental pollution in the early stages. After economic development has reached a certain level, the application of new environmental remediation technologies and methods can accelerate environmental restoration. Therefore, we hypothesized that the relationship between economic development and environmental pollution would exhibit an inverted V in late-developing regions. We examined water quality changes in 353 monitoring sections of 76 urban rivers in Kunming, southwestern China, over the last 33 years to assess the impact of economic development on river water quality. The results indicate that the relationship between the comprehensive pollution index of urban rivers and the economy shows an inverted V, supporting our hypothesis. The inverted V could be divided into four areas: an environmental self-purification area (<2170 USD); an economic development environmental destruction area (2170-5240 USD); an economic development feedback environment area (5240-11,255 USD); and an economic development promotion environment area (>11,255 USD). On the time axis of economic development, the relationship between economic development and environmental pollution is closer to an inverted U in relatively early developing regions, but the experience with and application of new technologies causes the relationship to change from an inverted U to an inverted V in relatively late-developing regions.

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Tangor, an important citrus type, is a hybrid of orange and mandarin and possesses their advantageous characteristics. Fruit quality is an important factor limiting the development of the citrus industry and highly depends on fruit development and ripening programs. However, fruit development and quality formation have not been completely explored in mandarin-orange hybrids. We sequenced the metabolome and transcriptome of three mandarin-orange hybrid cultivars at the early fruiting [90 days after full bloom (DAFB)], color change (180 DAFB), and ripening (270 DAFB) stages. Metabolome sequencing was performed to preliminarily identify the accumulation patterns of primary and secondary metabolites related to fruit quality and hormones regulating fruit development. Transcriptome analysis showed that many genes related to primary metabolism, secondary metabolism, cell wall metabolism, phytohormones, and transcriptional regulation were up-regulated in all three cultivars during fruit development and ripening. Additionally, multiple key genes were identified that may play a role in sucrose, citric acid and flavonoid accumulation, cell wall modification, and abscisic acid signaling, which may provide a valuable resource for future research on enhancement of fruit quality of hybrid citrus. Overall, this study provides new insights into the molecular basis of pulp growth and development regulation and fruit quality formation in mandarin-orange hybrids.

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Objective@#To evaluate snack consumption and the influencing factors associated with student participation in the Nutrition Improvement Program, and to provide a scientific basis for improving the program.@*Methods@#Among the 50 monitoring counties that implemented the Compulsory Education Student Nutrition Improvement Program, two primary schools and two junior schools were randomly selected according to different food supply patterns (i.e., school, company, and mix). This study randomly selected one or two classes from each grade, which ranged from grade 3 to grade 9. A questionnaire, which addressed snack consumption and choice, was distributed to 27 374 students.@*Results@#The findings revealed that 14.0% of students from poor rural areas in central and western regions consumed snacks two or more times per day, and 21.6% of students spent 3 yuan or more on snacks each day. The top three choices of snacks included fruit and vegetables (50.6%), biscuits and bread (50.1%), and puffed food (40.0%). Students who had mothers who worked outside the home, parents who worked outside the home, who consumed corporate meals, and who had access to a small shop on campus were more likely to consume snacks one or more times per day(OR=1.35，1.19，1.11，1.51，P<0.05).@*Conclusion@#The phenomenon of snack consumption among primary and middle school students from poor rural areas in central and western regions is common, and the selection of unhealthy snacks was identified as a problem. A health education system with comprehensive support and guidance from individuals, families, schools, and society should be established to guide students to opt for healthier snacks.

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Objective@#To explore the intervention effect of multiple nutritional health guidelines for school-aged children on the knowledge, attitudes and practices (KAP) of primary school students in Chengdu.@*Methods@#A primary school in Chengdu, which had a school canteen, was selected as the intervention school, and another similar primary school was selected as the control school. Students from the intervention school received nutritional education for six months, while the control school did not provide such intervention measures. A total of 589 students from grades 3 to 5 were selected to participate in the questionnaire survey(eligible 558, missing 31).@*Results@#Before the intervention, no significant difference was found in the rate of awareness regarding nutritional knowledge, including dietary attitudes and dietary behavior. After the intervention, the rate of awareness of nutritional knowledge and the overall awareness rate reached more than 80% in the intervention group, which was significantly higher than that observed in the control group(P<0.05). The intervention group consumed less than one type of breakfast food(26.6%), which was less than the control group(49.4%). The frequency of weekly egg and milk consumption was higher in the experimental group than in the control group. The proportion of students who consumed three or more types of vegetables daily was higher in the intervention group than in the control group. The proportion of leftovers was lower in the intervention group (15.8%) than in the control group(57.9%).@*Conclusion@#The comprehensive nutritional education based on a variety of nutritional health guidelines for school-age children can enhance students awareness of nutritional knowledge and healthier dietary behaviors.

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Experiments were conducted to investigate the removal of remazol golden yellow dye in order to assess the effectiveness and feasibility of microwave enhanced chlorine dioxide (ClO(2)) catalytic oxidation process. The catalyst used in this process was CuO(n)-La(2)O(3)/gamma-Al(2)O(3). The operating parameters such as the ClO(2) dosage, catalyst dosage, and pH were evaluated. The results showed that microwave enhanced catalytic oxidation process could effectively degrade remazol golden yellow dye with low oxidant dosage in a short reaction time and extensive pH range compared to the conventional wet catalytic oxidation. Under the optimal condition (ClO(2) concentration 80 mg/L, microwave power 400 W, contacting time 1.5 min, catalyst dosage 70 g/L, and pH 7), color removal efficiency approached 94.03%, corresponding to 67.92% of total organic carbon removal efficiency. It was found that the fluorescence intensity in microwave enhanced ClO(2) catalytic oxidation system was about 500a.u. which was verified that there was much hydroxyl radical produced. Compared with different processes, microwave enhanced ClO(2) catalytic oxidation system could significantly enhance the degradation efficiency. It provides an effective technology for dye wastewater treatment.

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In order to develop a catalyst with high activity and stability for microwave assisted ClO2 catalytic oxidation, we prepared CuOn-La2O3/gamma-Al2O3 by impregnation-deposition method, and determined its properties using BET, XRF, XPS and chemical analysis techniques. The test results show that, better thermal ability of gamma-Al2O3 and high loading of Cu in the catalyst can be achieved by adding La2O3. The microwave assisted ClO2 catalytic oxidation process with CuOn-La2O3/gamma-Al2O3 used as catalyst was also investigated, and the results show that the catalyst has an excellent catalytic activity in treating synthetic wastewater containing 100 mg/L phenol, and 91.66% of phenol and 50.35% of total organic carbon (TOC) can be removed under the optimum process conditions. Compared with no catalyst process, CuOn-La2O3/gamma-Al2O3 can effectively degrade contaminants in short reaction time and with low oxidant dosage, extensive pH range. The comparison of phenol removal efficiency in the different process indicates that microwave irradiation and catalyst work together to oxidize phenol effectively. It can therefore be concluded from results and discussion that CuOn-La2O3/gamma-Al2O3 is a suitable catalyst in microwave assisted ClO2 catalytic oxidation process.

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The catalyst of CuOx/Al2O3 was prepared by the dipping-sedimentation method using gamma-Al2O3 as a supporter. CuO and Cu2O were loaded on the surface of Al2O3, characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In the presence of CuOx/Al2O3, the microwave-induced chlorine dioxide (ClO2) catalytic oxidation process was conducted for the treatment of synthetic wastewater containing 100 mg/L phenol. The factors influencing phenol removal were investigated and the results showed that microwave-induced ClO2-CuOx/Al2O3 process could effectively degrade contaminants in a short reaction time with a low oxidant dosage, extensive pH range. Under a given condition (ClO2 concentration 80 mg/L, microwave power 50 W, contact time 5 min, catalyst dosage 50 g/L, pH 9), phenol removal percentage approached 92.24%, corresponding to 79.13% of COD(Cr) removal. The removal of phenol by microwave-induced ClO2-CuOx/Al2O3 catalytic oxidation process was a complicated non-homogeneous solid/water reaction, which fitted pseudo-first-order by kinetics. Compared with traditional C1O2 oxidation, ClO2 catalytic oxidation and microwave-induced ClO2 oxidation, microwave-induced ClO2 catalytic oxidation system could significantly enhance the degradation efficiency. It provides an effective technology for the removal of phenol wastewater.

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