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Water resources are important natural resources and play a key role in economic development and social life. China is one of the countries with the most serious water shortage in the world. In the next few decades, the contradiction between supply and demand of water resources will always plague China. Increasing the use of unconventional water resources to mitigate the water crisis is necessary way to achieve a sustainable development. There has been no effective standard yet in China to evaluate the exploitation level and potential of unconventional water resources. This study describes the current status of the exploitation and aims at establishing an evaluation system incorporating the three relevant factors, namely, driving, restrictive, and risk factors respectively, and provides a theoretical basis for the management of unconventional water resources in China. In order to mine the relationship between data and evaluation indexes, the rough set theory is adopted to determine the weight and objectively reflect the importance of each evaluation index. On the basis of the evaluation system, relevant data from 2006 to 2017 in Beijing were selected, and the results show that the urgency of unconventional water resources development in Beijing was generally on the rise with a small fluctuation range.

The shortage of water resources has seriously restricted the development of cities. Unconventional water resources is of great significance for sustainable development. As a city lack of water, Los Angeles plans to develop reclaimed water as an important component of urban water supply under the conditions of drought and over exploitation of groundwater. In order to provide a basis for urban reclaimed water construction planning, this paper developed a system dynamic model to provide scientific suggestions for the planning of reclaimed water. According to the analysis of Los Angeles water system, the model divides the system into reclaimed water system, urban water consumption system, urban water supply system and water supply cost system. The degree of water shortage, urban water supply, water supply cost, and reclaimed water production were chosen as the model index for the requirement of plan design. The historical data was employed to verify the model, indicating that the model is reliable. Then the plans under different rates of growth of reclaimed water were designed. According to the comprehensive analysis of the model index, the second plan was considered to be the optimal one: increase the local water supply in Los Angeles to 50 percent of the total by 2035 and reduce purchases by 50 percent. Finally, Reclaimed water accounts for 30% of the city’s water supply, meanwhile, water supply costs decline 10%.

BACKGROUND: The tobacco‐rice rotation cropping (TRRC) is an ecologically friendly system that can both alleviate soil nicotine pollution and decrease the brown planthopper (BPH, Nilaparvata lugens Stål) fitness on rice. However, few studies on this green and effective rotational cropping system have been reported. In particular, the underlying mechanisms of TRRC on the significant reduction of field pest population at the molecular level is still unknown. RESULTS: Field investigation showed that BPH population decreased significantly in TRRC than in rice‐rice successive cropping (RRSC) field. In addition, the short neuropeptide F (NlsNPF) and its receptor NlA7 of BPH had half‐times lower levels in the TRRC field. Behavioral bioassay indicated a 1.93‐fold increase in the number of salivary flanges of the dsNlsNPF group, while BPH fitness parameters, such as honeydew, weight gain, and mortality decreased significantly. Dopamine (DA) content in BPH decreased by ~11.1% under the influence of nicotine, and its presence increased the expression levels of NlsNPF and NlA7. Exogenous DA application eliminated the inhibitory effects of nicotine on BPH feeding and restored the fitness levels of its parameters. Independent application of either a mixture of dsNlsNPF with a nanocarrier or nicotine to the normal rice field revealed that the latter could produce better effects in combination with dsRNA. CONCLUSION: These findings confirmed that DA regulated NlsNPF to inhibit the BPH feeding behavior in TRRC. The results not only provided novel findings on the mechanism of pest‐host interactions, but also presented new method for integrated pest management. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The fate and transport of pollutants in the subsurface is usually predicted using numerical simulations. Comparisons of the simulation results with experimental data are required to validate the numerical codes. In this paper, the nonaqueous phase liquid (NAPL) simulator code was used to numerically simulate two centrifugal light nonaqueous phase liquid (LNAPL) transport experiments. The numerical predictions were compared with the centrifugal test results and the impact of capillary hysteresis was evaluated. It was concluded that the simulation with the nonhysteretic model slightly underestimated the LNAPL volume retained in the vadose zone, and the average error of the predicted LNAPL saturation in the vadose zone and along the plume centerline was approximately 5% to 10%. The application of capillary hysteresis for the numerical simulation of the second centrifuge test has eliminated this error. In addition, accounting for hysteresis in the numerical simulation of the second centrifuge test has considerably improved the predicted results with respect to the size of the lens-shaped plume within the capillary fringe. However, there were inconsistencies between the numerical and experimental results, especially with respect to the time for the LNAPL to reach the groundwater level. This was found to be due to overestimation of the simulated downward infiltration of the LNAPL in the capillary fringe. It was found that the pore-connectivity parameter with a value of 0.66 for the relative permeability-saturation model produced the best comparison with experimental results. Key words: light nonaqueous phase liquid (LNAPL), numerical simulation, centrifugal modeling, contaminant transport, vadose zone, capillary fringe, capillary hysteresis, pore connectivity. La destinee et le transport de polluants dans l'eau souterraine sont generalement predits a l'aide de simulations numeriques. La comparaison des resultats simules avec des donnees experimentales est essentielle afin de valider les codes numeriques. Dans cet article, le code de simulation liquide non miscible (NAPL) a ete utilise pour simuler numeriquement deux essais en centrifugeuse sur le transport de liquide non miscible leger (LNAPL). Les predictions numeriques ont ete comparees aux resultats d'essais en centrifugeuse, et l'impact de l'hysteresis sur la capillarite a ete evalue. Il a ete conclu que la simulation avec le modele sans hysteresis sous-estimait legerement le volume de LNAPL retenu dans la zone vadose, et que l'erreur moyenne de la saturation de LNAPL predite dans la zone vadose et le long de la ligne centrale du panache etait d'environ 5 a 10%. L'application de l'hysteresis sur la capillarite pour la simulation numerique du deuxieme essai en centrifugeuse a elimine cette erreur. De plus, le fait de considerer l'hysteresis lors de la simulation numerique du deuxieme essai en centrifugeuse a grandement ameliore les resultats predits par rapport a la taille du panache en forme de lentille a l'interieur de la frange capillaire. Cependant, il y avait des incoherences entre les resultats numeriques et experimentaux, particulierement par rapport au temps necessaire au LNAPL pour atteindre le niveau d'eau souterraine. Les recherches ont demontre que ceci est du a une surestimation de l'infiltration simulee vers le bas du LNAPL dans la frange capillaire. Il est aussi demontre qu'un parametre de connectivite des pores de 0,66 pour le modele permeabilite relative-saturation permet d'obtenir les meilleures comparaisons avec les resultats experimentaux. [Traduit par la Redaction] Mots-cles: liquide non miscible leger (LNAPL), simulation numerique, modelisation par centrifugation, transport de contaminants, zone vadose, frange capillaire, hysteresis sur la capillarite, connectivite des pores., Introduction Accidental spills and releases of hazardous chemicals onto soil or leakages from underground storage tanks (USTs) and pipelines are major sources of soil and groundwater contamination, which have posed [...]

As the current pandemic has shown, lateral flow assays (LFAs) are a prime example of point-of-care devices enabling quick testing at an affordable price. However, their ease of use undeniably affects their sensitivity, making them less sensitive than other multi-step and time-consuming diagnostic assays, such as polymerase chain reactions and enzyme-linked immunosorbent assays. A possible solution to overcome this lack of sensitivity is the exploitation of bottom-up approaches to synthesize nanomaterials with outstanding properties for use as colorimetric labels in LFAs, that is, using nanoparticles with better optical capabilities to improve the generation of the colorimetric signal and the overall sensitivity of LFAs. Following this strategy, we rationally optimized the synthesis of gold and iridium oxide nanoflowers (Au–IrO2 NFs) to enhance their physical–chemical properties as colorimetric labels in LFAs. Specifically, we were able to rationally control their size (from 155 to 53 nm in diameter) in order to guarantee an optimal flow along the different pads of a LFA. Moreover, thanks to their superior plasmonic behavior (compared to standard AuNPs), we could achieve an 8.5-fold lower limit of detection (down to 1.2 ng/mL) for human immunoglobulin G (HIgG) than standard LFAs (10.1 ng/mL). Therefore, due to their optical and redox properties, bioconjugation capabilities, and synergic combination of the individual components, Au–IrO2 NFs appear as potential candidates for the next generation of optical LFAs. [ABSTRACT FROM AUTHOR]

The Discussion revises the figure that compares different equivalent-diameter equations for prefabricated vertical drains, and the result of another equivalent equation that has been widely used in practice is also added into the figure. In addition, a three-dimensional (3D) numerical model is developed to compare with the two-dimensional (2D) numerical model used in the paper. The result indicates that the difference between the 3D and 2D models can be about 5%. Key words: prefabricated vertical drain (PVD), equivalent equation, three- dimensional (3D) numerical model. La Discussion presente une revision de la figure comparant differentes equations du diametre equivalent pour des drains verticaux prefabriques, et le resultat d'une autre equation equivalente qui est couramment utilisee en pratique est aussi ajoute a la figure. De plus, un modele numerique en trois dimensions (3D) est developpe afin de le comparer avec le modele en deux dimensions (2D) utilise dans cette etude. Les resultats indiquent que la difference entre le modele 3D et le modele 2D peut etre d'environ 5 %. [Traduit par la Redaction] Mots-cles: drain vertical prefabrique (DVP), equation equivalente, modele numerique en trois dimensions (3D)., Introduction Currently, a prefabricated vertical drain (PVD) is thought to be one of the most useful and effective methods for accelerating soil consolidation by promoting radial flow. Several analytical models [...]