There are currently many problems related to excessive fertilizer application, low fertilizer-use efficiency and lack of an agricultural labor force for cotton production in China. Therefore, the ...objective of this paper was to explain the optimal application time for once fertilization based on cotton nutrient accumulation of nitrogen, phosphorus and potassium to provide technical support for simplified fertilization management in cotton production. A 2 yr field experiment and a 1 yr pot experiment were conducted with fertilizer (225, 67.5, and 225 kg ha
of N, P
O
, and K
O, respectively) applied once at 0 (FT1), 5 (FT2), 10 (FT3), 15 (FT4), or 20 (FT5) d after the appearance of the first flower and a triple application (preplant 30%, first bloom 40%, and peak bloom 30%) as the conventional control (FT6). The results showed that FT1 exhibited the greatest nutrient accumulation speed for both the average (5.81, 1.22, and 5.74 kg ha
of N, P
O
, and K
O, respectively) and the maximum (6.31, 1.44, and 6.24 kg ha
of N, P
O
, and K
O, respectively) during the fast accumulation period. Moreover, among the different treatments, FT1 exhibited the greatest nutrient recovery and partial productivity. The results suggest that applying the minimum amount of fertilizer at the appearance of the first flower is optimal for maximizing nutrient utilization while minimizing environmental disturbance.
Meeting foxtail millet (Setaria italica L.) (FM) production targets of high grain yield requires appropriate genotype selection and nitrogen (N) fertilization. However, high input costs and low crop ...yields are the major concerns for FM production systems, particularly in dry regions. To reduce the production costs without sacrificing yield, we assumed that N fertilization would increase the grain yield of FM varieties by improving reproductive organ biomass accumulation. To test this hypothesis, a two-year (2017 and 2018) field investigation in a randomized complete block design with split plot arrangement and three replicates was carried out on FM varieties, namely, V1 (Zhangzagu 8; hybrid) and V2 (Bagu 214; common) to ascertain the effects of five N levels (N1—15; N2—61; N3—108; N4—155; N5—201 kg N ha−1) on biomass accumulation and grain yield at different growth stages. Results showed that the V1 variety had a 34.8% and 28.5% higher grain yield compared to V2 treatment in both years, respectively. The interaction between variety and nitrogen was also significant. The combination of V1 and N4 produced a higher grain yield in both years. This increase in V1 grain yield was supported by the evidence of greater reproductive organ biomass formation, with a 113 and 120 kg ha−1 higher-than-average rate of biomass accumulation in both years, respectively. Among N rates, the N4 level resulted in a higher grain yield (3226 kg ha−1) and (3437 kg ha−1) compared with other N rates in the 2017 and 2018 growing seasons. This higher yield under N4 treatment was confirmed by a higher reproductive organ biomass accumulation at various growth phases, with 138 kg ha−1 and 124 kg ha−1 in 2017 and 2018, respectively. We also noticed that further increases in nitrogen levels did not increase FM grain yield. Conclusively, these data display the significance of proper FM production management techniques. Growing the varieties Zhangzagu 8 at 155 kg N ha-1 fertilization and Bagu 214 at 108 kg N ha−1 fertilization could be promising options to achieve higher grain yield.
•Moderate plant density yielded higher cotton fiber compared to either lower or higher density.•Higher cotton yield was resulted from higher reproductive organs biomass and K acquisition.•Earlier ...sowing date could have a good harvest only accompanied with a moderate plant density.
Cotton is the fifth major oil crop and grown primarily for natural fiber globally. Suitable management practices like planting density (PD) and sowing date (SD) are the major drivers of cotton crop productivity. Cotton production with a normal practice of 3 plants m−2 in Yangtze River Valley China, resulting in an average yield of 1200kgha−1 although, high input costs and low productivity are the two major consequences in cotton production systems. The production costs can be decreased and profits can be increased through optimal PD and adjusting SD. The objectives of this study were to optimize growth, yield, biomass partitioning and potassium (K) distribution of a cotton crop under a short growing season and elevated PD. Experiments were conducted with two sowing dates i.e. early (S1, May 20 and late S2, June 04) as the main plot and three plant densities (D1, low 7.5; D2, moderate; 9.0 and D3, high; 10.5plantsm−2) as the subplot laid out in a split arrangement with four replicates. D3 crops significantly delayed cotton growth period under late sowing date compared with early planted crops. Compared with S2 crops, S1 plants produced 29% and 26% higher seed cotton and lint yield, respectively. Among the PD, D2 plants produced 12%, 15%, 13% and 6% more seed cotton yield and lint yield over D1 and D3 crops respectively. The increment in yield was due to increased plant reproductive organs biomass occasioned by moderate density and longer cropping season which allowed the utilization of available resources. Higher K acquisition i.e. (0.9VMkgha−1d−1), further improved reproductive structures formation in S1 combined with D2 crops. The S1 in combination with D2 crops resulted in the highest average (77VTkgha−1d−1) and maximum (93VMkgha−1d−1) rates of reproductive organs biomass accumulation than other combinations. Conclusively, use of medium density under both sowing dates is an effective strategy for optimal seed cotton and lint yield.
•Moderate to high density increased lint yield under late sowing date.•Moderate density resulted higher reproductive organ nitrogen rates.•Moderate population enhanced cotton leaf net photosynthetic ...capacity.•Moderate density with later or lower density with earlier sowing is an optimal strategy for improving lint yield.
This study assesses the effects of plant population density (PPD) and sowing date (SD) on growth, physiology and lint yield of a cotton crop. Seedling transplanting is one of the most dominant cotton production systems in China. But on the other hand, the net benefit is decreasing because the system is labor intensive. Therefore, a shorter cotton growing season is urgently needed to reduce the production costs through management practices such as adjusting sowing date and PPD. The following hypothesis was tested; would cotton yield and physiology from a late sowing be compensated by plant density? Field experiments were conducted with two sowing dates (S1, May 20; S2, June 04) as the main plot and three PPDs (D1, low; 7.5×104; D2, moderate; 9.0×104 and D3, high; 10.5×104ha−1) as the sub-plot. Early-sown plants produced 23%, 32%, 55%, 77% and 14%, taller stems more nodes, leaves and fruits, respectively, than the late-sown plants. Consequently, S1 produced 26% higher lint yield than S2. This increase in lint yield was mainly attributed to a relatively longer cropping season, which allowed utilization of available resources. Growth and fruit production in S1 plants were further increased by an increased photosynthetic rate (Pn) and N acquisition. Across the plant densities, 13% and 6% more lint yield was achieved under D2 than the D3 and D1, respectively. Moderate PPD increased lint yield by 13% and 6% over high and low, respectively. Nitrogen (N) acquisition was 45%, 33%, higher for S1 sown crop compared with S2, respectively. S1D2 had higher average (3.5VTkgha−1d−1) and maximum (4.5VMkgha−1d−1) rates of N accumulation in reproductive organs at the fastest accumulation point among other treatments. Our data suggest that for both sowing dates moderate PPD is a promising option, which allows light interception and penetration to the lower canopy, efficient N utilization and assimilate distribution to reproductive structures.
Agricultural production enhancement has been realized by more consumption of fossil energy such as fertilizer and agrochemicals. However, the production provides the present human with sufficient and ...diversified commodities, but at the same time, deprives in some extent the resources from the future human as well. In the other hand, it is known that synthetic herbicides face worldwide threats to human’s health and environment as well. Therefore, it is a great challenge for agricultural sustainable development. The current review has been focussed on various oilseed crop species which launch efficient allelopathic intervention, either with weeds or other crops. Crop allelopathic properties can make one species more persistent to a native species. Therefore, these crops are potentially harmful to both naturalized as well as agricultural settings. On the other side, allelopathic crops provide strong potential for the development of cultivars that are more highly weed suppressive in managed settings. It is possible to utilize companion plants that have no deleterious effect on neighbor crops and can be included in intercropping system, thus, a mean of contributing to agricultural sustainable development. In mixed culture, replacement method, wherein differing densities of a neighbor species are planted, has been used to study phytotoxic/competitive effects. So, to use alternative ways for weed suppression has become very crucial. Allelochemicals have the ability to create eco-friendly products for weed management, which is beneficial for agricultural sustainable development. Our present study assessed the potential of four oilseed crops for allelopathy on other crops and associated weeds.
•We introduce a new railway timetable optimization model to simultaneously consider the stopping patterns and train schedule.•We propose the use of an innovative column-generation-based heuristic to ...solve a very-large train timetable problem.•We illustrate the use of the model and algorithm to improve the timetable of a real-world HSR system.
High-speed railway (HSR) systems have been developing rapidly in China and various other countries throughout the past decade; as a result, the question of how to efficiently operate such large-scale systems is posing a new challenge to the railway industry. A high-quality train timetable should take full advantage of the system’s capacity to meet transportation demands. This paper presents a mathematical model for optimizing a train timetable for an HSR system. We propose an innovative methodology using a column-generation-based heuristic algorithm to simultaneously account for both passenger service demands and train scheduling. First, we transform a mathematical model into a simple linear programming problem using a Lagrangian relaxation method. Second, we search for the optimal solution by updating the restricted master problem (RMP) and the sub-problems in an iterative process using the column-generation-based algorithm. Finally, we consider the Beijing–Shanghai HSR line as a real-world application of the methodology; the results show that the optimization model and algorithm can improve the defined profit function by approximately 30% and increase the line capacity by approximately 27%. This methodology has the potential to improve the service level and capacity of HSR lines with no additional high-cost capital investment (e.g., the addition of new tracks, bridges and tunnels on the mainline and/or at stations).
Background
Preschool represents the budding and initial stage of bullying behavior, where perpetration of physical bullying predominates as the primary form of bullying. An in-depth understanding of ...the factors linked to preschool physical bullying behavior is crucial for enabling early prevention and intervention strategies.
Objective
The purpose of this study was to examine the relationship between Theory of Mind and physical bullying behavior in 4–6 years old children in kindergarten and the mediating role of peer rejection and gender in this relationship.
Methods
Data on perpetration of physical bullying and peer rejection were obtained from 310 preschool children (age range = 52–79 months, M = 66.85, SD = 7.04) by the peer nomination method, and their Theory of Mind was measured by the Theory of Mind Development Scale.
Results
The results showed that Theory of Mind negatively predicted perpetration of physical bullying in preschool children and that Theory of Mind was related to perpetration of physical bullying in preschool children only through peer rejection. Boys were also found to have a stronger association between peer rejection and perpetration of physical bullying in preschool children than girls.
Conclusion
Peer rejection may play a mediating role between Theory of Mind and perpetration of physical bullying in preschool children. In addition, the relationship between peer rejection and perpetration of physical bullying appears to be stronger for boys than for girls. This contributes to our understanding of the relationship between Theory of Mind and perpetration of physical bullying in preschool children and has implications for how bullying prevention and intervention can be tailored to the gender of young children.
This study presents a straightforward route to fabricate robust poly(vinyl alcohol) (PVA)/polyethyleneimine-functionalized graphene (PVA/rGO/PEI) composite films by combining of surface modification, ...reduction and composite preparation. Branched polyethylenimine (PEI), as an effective reducing agent and surface modifier of graphene oxide (GO), has been presented to yield PEI-functionalized graphene in PVA aqueous solution. The obtained PVA/PEI-functionalized graphene composites exhibited significant improvements in strength and toughness. At a PEI: GO ratio of 0.5:1, the tensile strength and Young's modulus of PVA/rGO/0.5PEI composite increased by 55.8% and 43.1%, respectively from pure PVA, and the elongation at break also increased from 77.1% (for PVA/GO composite) to 147.3%. With regard to simultaneous strengthening and toughening effects, the strong interfacial interactions produced by the mechanism of hydrogen bonding between amine of PEI and hydroxyl groups of PVA play a key role, which not only increase load transfer efficiency but accelerate crystallization of PVA.
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•A facile one-pot strategy was proposed to fabricate PVA/functionalized graphene composites.•GO was simultaneously functionalized and reduced by PEI in PVA aqueous solution.•Strong interfacial interactions were built between PEI-functionalized graphene and PVA.•PEI-functionalized graphene/PVA composites exhibited greatly improvements in strength and toughness.
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Herein, a superhydrophobic and superoleophilic melamine sponge is fabricated by immersing the original sponges in ethanol solution containing tannin acid and n-octadecylamine. ...Meanwhile, the reagents are more economical and eco-friendly than commonly superhydrophobic modified materials such as dopamine, graphene, and 1-dodecanethiol. By integrating the high porosity, superior elasticity, and mechanical stability of the raw sponge with the low surface energy of n-octadecylamine and their nanometer scale roughness, the modified sponge not only possesses superhydrophobic surface with the water contact angle of 154.8°, but also exhibits excellent adsorption performance (absorption weight ranging from 70 to 148 times of its own) and extraordinary recyclability. The treated sponge also have superb separation efficiency for oil/water mixtures and emulsions, 99.95% and 99.57%, respectively. Besides, the simple processing is easy to scale up. All the merits manifest that this superhydrophobic sponge is the desired candidate for handing oil pollution in the sea.
Ce-UiO-66 was firstly used as a supercapacitor electrode material and exhibited a high capacitance of 6.9 Fcm−2 in a redox electrolyte.
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A novel self-supported structure of ...Ce-UiO-66/TNF was firstly synthesized by growing Ce-UiO-66 on a TNF substrate. This novel Ce-UiO-66/TNF material was proved to possess a high supercapacitive performance in the redox electrolyte of Fe(CN)63−/4−, and it was also the first study for Ce-UiO-66 material on the supercapacitor application. High specific capacitances of 6.9 and 2.5 Fcm−2 can be achieved at large current densities of 20 and 80 mAcm−2, respectively. After 10,000 charge-discharge cycles, the capacitance retention can be kept at 95% and the coulomb efficiency can be maintained over 98%. Such outstanding electrochemical performance may be related to the redox property of the electrolyte, high specific surface area of the Ce-UiO-66 material, porous characteristic of the TNF substrate and self-supported structure of the whole electrode.
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