Optimizing rice yield, quality and nutrient use efficiency through combined application of nitrogen and potassium.

Reasonable nitrogen (N) and potassium (K) application rates can effectively improve fertilizer use efficiency, rice yield and quality. A two-year field experiment was conducted with combined application of three N rates (135, 180, and 225 kg ha-1, denoted as N1-N3) and four K rates (0, 90, 135, and 180 kg ha-1, denoted as K0-K3) using super indica hybrid rice cultivar Yixiangyou (YXY) 2115 to explore the effects of co-application of N and K on rice growth and development. The results indicated that the combined application of N and K had significantly interactive effects on dry matter (DM) accumulation, nutrients absorption, N harvest index (NHI), K harvest index (KHI), spikelets per panicle and most rice quality indexes. The highest total DM accumulation (17998.17-19432.47 kg ha-1) at maturity stage was obtained under N3K2. The effect of co-application of N and K on nutrients absorption and utilization varied between the two years and within each year. The highest total N and K accumulations at maturity stage were observed under N3K1 and N3K2, respectively, while the highest N recovery efficiency (NRE) and K recovery efficiency (KRE) were observed under N1K3. High expression levels of N and K metabolism-related genes in rice grains were observed under N3K2 or N3K3, consistent with N and K uptake. Co-application of N and K increased rice yield significantly and the highest yield (6745.02-7010.27 kg ha-1) was obtained under N2K2. As more N was gradually applied, rice appearance quality improved but milling, cooking and eating quality decreased. Although appropriate application of K could improve rice milling, cooking and eating quality, it reduced appearance quality. The optimal milling, cooking and eating quality were obtained under N1K2, while the best appearance quality was obtained under N3K0. Overall, a combination of 135-210 kg ha-1 N and 115-137 kg ha-1 K application rates was recommended for achieving relatively higher yield and better quality in rice production.

How school policies, strategies, and relational factors contribute to teacher victimization and school safety.

In this study, we examined how school policies and strategies (i.e., positive discipline, hardening strategies, and positive behavioral strategies) affect teacher relational factors and teacher reports of victimization and safety. Specifically, we examined the mediational roles of teacher support of student learning, maltreatment of students by teachers, and teachers' differential treatment of students in schools. Using a sample of 6643 pre-K-12th-grade teachers, path analysis results revealed that positive behavior strategies, hardening strategies, and positive discipline were indirectly associated with teacher victimization and sense of safety. Additionally, teachers' perceptions of other teachers maltreating students had the greatest contributions to their sense of safety and victimization by students. Positive discipline was directly and indirectly associated with teacher victimization and safety. Implications and directions for future studies are discussed.

Effects of water stress on starch synthesis and accumulation of two rice cultivars at different growth stages.

Rice is a water intensive crop and soil water conditions affect rice yield and quality. However, there is limited research on the starch synthesis and accumulation of rice under different soil water conditions at different growth stages. Thus, a pot experiment was conducted to explore the effects of IR72 (indica) and Nanjing (NJ) 9108 (japonica) rice cultivars under flood-irrigated treatment (CK, 0 kPa), light water stress treatment (L, -20 ± 5 kPa), moderate water stress treatment (M, -40 ± 5 kPa) and severe water stress treatment (S, -60 ± 5 kPa) on the starch synthesis and accumulation and rice yield at booting stage (T1), flowering stage (T2) and filling stage (T3), respectively. Under LT treatment, the total soluble sugar and sucrose contents of both cultivars decreased while the amylose and total starch contents increased. Starch synthesis-related enzyme activities and their peak activities at mid-late growth stage increased as well. However, applying MT and ST treatments produced the opposite effects. The 1000-grain weight of both cultivars increased under LT treatment while the seed setting rate increased only under LT3 treatment. Compared with CK, water stress at booting stage decreased grain yield. The principal component analysis (PCA) showed that LT3 got the highest comprehensive score while ST1 got lowest for both cultivars. Furthermore, the comprehensive score of both cultivars under the same water stress treatment followed the trend of T3 > T2 > T1, and NJ 9108 had a better drought-resistant ability than IR72. Compared with CK, the grain yield under LT3 increased by 11.59% for IR72 and 16.01% for NJ 9108, respectively. Overall, these results suggested that light water stress at filling stage could be an effective method to enhance starch synthesis-related enzyme activities, promote starch synthesis and accumulation and increase grain yield.

Evolution of phosphorus with the promotion of KOH in supercritical water gasification of dewatered cyanobacteria from ion perspective.

Phosphorus is a very important resource, and dewatered cyanobacteria contains a large amount of it. Basic additives, such as KOH, are often used to promote hydrogen production during supercritical water gasification (SCWG) of biomass, but their effects phosphorus transformation have rarely been investigated. In this study, SCWG of dewatered cyanobacteria with potassium salt and KOH was conducted in autoclave at 400 °C for 10 min, to investigate the effect of K+ on the transformation of phosphorus under neutral and alkaline conditions. Results showed that K+ increased the proportion of phosphorus in the solid phase from 88.4% to 90.8-98.3%. Furthermore, K+ could promote the transformation of iron-combined phosphorus to calcium-combined phosphorus and occluded phosphate. Only when the reaction environment was alkaline, the proportion of phosphorus in the solid phase was significantly reduced to a minimum of 26.1%. When the amount of OH- was sufficient, can this part of phosphorus and organic phosphorus, which was decomposed and transformed by the promotion of OH-, be transferred to the liquid products. Results from this study laid a foundation simultaneously for hydrogen production and phosphorus recovery more environmentally and high-effectively.

Hydrothermal carbonization coupling with liquid dimethyl ether extraction pretreatment of sewage sludge: Hydrochar performance improvement and low-nitrogen biocrude production.

Hydrothermal carbonization of sewage sludge converts waste into hydrochar; however, the complex organic composition of feedstock limits the product value. A novel process that combines liquid dimethyl ether extraction and hydrothermal carbonization (DE-HTC) was proposed for improving the product value by simultaneously producing biocrude/hydrochar and improving feedstock suitability for thermochemical conversion. Biocrude and hydrochar with a product yield of 2.62% and 55.83% were produced via DE-HTC, respectively. The hydrochar yield increased by 12.65%-29.90% compared to traditional single-step hydrothermal carbonization. The hydrochar energy densification was decreased by 1.16%-10.28%, while hydrochar's energy yield increased by 47%-66%, and it had a more prominent porous structure. By avoiding the decomposition of proteins during thermochemical conversion, the nitrogen content of the biocrude obtained via DE-HTC was only 0.38%. The biocrude was also further qualitatively analyzed. This study provides insights into the efficacy of a novel hydrothermal method with distinct product value advantages over direct hydrothermal carbonization.

Interparental and Intergenerational Co-parenting Conflict and Adolescent Academic Performance: The Mediating Roles of Adolescent Academic Engagement and Depression.

While a link between co-parenting conflict and academic performance is frequently assumed, studies on this association have shown inconsistent results. In addition, academic engagement and depression can potentially mediate the association between co-parenting conflict and academic performance. However, studies have not tested this proposition. This paper examined the direct effect of co-parenting conflict on adolescent academic performance and the mediating effect of academic engagement and depression. Using data from a nationally representative survey, the 2020 China Family Panel Studies (CFPS), we constructed a sample of 1989 dyads of adolescents (aged 10 to 15) and their primary caregivers in China. The structural equation model analysis revealed that co-parenting conflict was not directly linked with academic performance but was indirectly associated with adolescent academic performance through academic engagement and depression. The findings provide empirical support that academic engagement and depression play important mediating roles in the relationship between co-parenting conflict and adolescent academic performance. Future intervention programs aimed at promoting adolescent academic performance may consider a family-oriented approach to identify adolescents from families with co-parenting conflict and provide them with professional support.

Interparental Violence and Early Adolescents' Adjustment Problems in China: Testing a Moderated Mediation Model of Parental Warmth and Emotional Insecurity.

This study analyzed the relationships between exposure to interparental violence and adolescents' adjustment problems. It also explored the mediating role of emotional insecurity and the moderating role of parental warmth in these relationships. Five hundred and seventy-eight early adolescents from three migrant primary schools and one public school in Beijing participated in this survey, reporting on their perceived interparental violence, emotional insecurity, post-traumatic stress symptoms (PTSS), and internalizing and externalizing behavioral problems. The results revealed that emotional insecurity partially mediated the association between interparental violence and all three indicators of adjustment problems, with stronger mediating effects on PTSS and internalizing problems than on externalizing problems; parental warmth buffered the association between emotional insecurity and internalizing/externalizing problems. This study adds insights to present literature on how interparental violence contributes to different aspects of adolescents' adjustment problems in the Chinese context.

Hydrothermal treatment of petrochemical sludge in subcritical and supercritical water: Oil phase degradation and syngas production.

The reaction process of petrochemical sludge under hydrothermal conditions was investigated to explore the feasibility of its disposal using hydrothermal treatment. Experiments were conducted in an autoclave for 30 min at 350-450 °C. During the hydrothermal treat of petrochemical sludge, 44.98%-59.64% of the oil (organic matter) in the sludge was decomposed into aqueous and gas products. The gas yield reached 1.37 mol/kg of organic matter at reaction temperature of 450 °C. The H2 yield was 0.26 mol/kg of organic matter. The primary product was still in the aqueous phase. The TOC concentration of the aqueous product was in the range of 14,960-19,050 mg/L. The concentration of COD, total phenol, and total nitrogen of product were in the ranges of 9029-10,870, 13.83-20.10, and 497.5-599.0 mg/L, respectively. The group analysis and GC-MS analysis of the residual oil indicated that the saturated long chain hydrocarbons (C18-C21) in petrochemical sludge had decomposed to form saturated short chain hydrocarbons (C11-C17); however, the short chain saturated hydrocarbons in the sludge had decomposed thoroughly. The removal rate of asphaltenes, resins and aromatic hydrocarbons were low. Finally, a mechanism for treating petrochemical sludge under hydrothermal conditions was proposed. The study provides an experimental basis for the hydrothermal treatment of petrochemical sludge.

Suppression of tar and char formation in supercritical water gasification of sewage sludge by additive addition.

This study explored the feasibility of char and tar formation inhibition during supercritical water gasification of sewage sludge (SS) by additive addition. Experiments were conducted in autoclave with 5 wt% additives at 400 °C for 30 min. The non-additive gasification of SS resulted in a higher char yield (12.6%) and tar yield (16.4%). In contrast, the five additives reduced the char yield (3.4-11.2%), the inhibition of char yield by additives was in the order of NaOH > K2CO3 > H2O2 > acetic acid > NiCl2. The inhibition of tar formation was limited, tar yield were 13.3-18.8% with additives. Fourier-transform infrared spectroscopy was used to determine the functional groups of char/tar, and it was observed that the spectra of char were more similar to those of hydrochar obtained in a low-temperature experiment. Model compounds of potential precursors was also tested to study the mechanism of action of additives, the results reveal that additives have different effects on char/tar formation from various components, the inhibitory effects of additives on the yield of char from humus and tar from lignin were limited. Finally, the effects of additives on gasification were also studied. The addition of additives will have an impact on the hydrogen yield and gasification efficiency, which also needs to be considered when use additive to reduce the by-products yield.

Indirect effect of parental depression on school victimization through adolescent depression.

BACKGROUND: While a link between parental depression and adolescent school victimization is frequently hypothesized, studies on this association have shown mixed results. In addition, adolescent depression has been considered a potential psychosocial mechanism underlying the link between parental depression and adolescent school victimization. However, studies to support this proposition are lacking. This paper examines the direct effect of parental depression on adolescent victimization by peers and teachers in school as well as indirect effect through adolescent depression in an Asian context (Taiwan) and further examines differences in the interrelationships of parental depression, adolescent depression, and school victimization by peers and teachers across gender and school age groups. METHODS: Data were obtained from a random sample of 2,419 students (grades 7-12) and their parents in one of the largest metropolitan areas in Taiwan. RESULTS: Parental depression did not have a significant direct association with either type of school victimization. However, parental depression showed a significant indirect association with both types of school victimization through adolescent depression. These findings applied to both males and females and both junior and senior high school students. LIMITATION: The study utilized cross-sectional data, and the findings cannot be used to build causal relationships. CONCLUSION: Our findings provide empirical support that parental depression has indirect associations with school victimization by peers and teachers through adolescent depression. The results support the importance of including family-based approaches for depression targeting parents and adolescents in future victim intervention/prevention school programs.

Personal, family, school, and community factors associated with student victimization by teachers in Taiwanese junior high schools: A multi-informant and multilevel analysis.

BACKGROUND AND OBJECTIVE: Unlike most other studies on school victimization, which mainly focused on student self-reports and one-level analysis, this study used a multi-informant and multilevel analysis to examine how personal and school factors reported by students (gender, grade level, delinquency, perpetration against the student, and quality of the teacher-child relationship), family factors reported by parents (family income, the family's financial stress, parent-child interaction, parental monitoring, parental psychological distress, parental involvement in school, and parental attitude towards corporal punishment), and community factors collected from government data (district/community poverty rates, and urban and rural areas) were associated with student reports of victimization by their teachers. PARTICIPANTS AND SETTING: 1262 junior high students (grades 7-9) and their parents/guardians in Taiwan. METHODS: Multi-stage cluster random sampling and self-administered questionnaire survey. RESULTS: A total of 38.7% of students reported maltreatment by teachers during the semester. The results of Hierarchical Linear Modeling showed that student delinquency, school violence perpetration, poor teacher-child relationships, the positive attitudes of parents toward corporal punishment, and communities/districts with low poverty rates were positively associated with student victimization. CONCLUSIONS: Psychological and corporal punishment in educational settings was legally banned in Taiwan in 2007. Our findings imply that legal prohibition is not enough to eliminate maltreatment by teachers. Comprehensive intervention programs are urgently needed, and potential intervention programs should target students from districts with low poverty rates. These programs should also focus on managing student delinquency and school violence, promoting supportive teacher-child relationships, and discouraging positive parental attitudes toward corporal punishment.