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To address the problems of long planning time, redundant planning path, and even planning failure caused by local constraints in narrow spaces in the rapid exploring random trees (RRT) algorithm when unmanned aerial vehicle is planning a path in a complex environment, an improved Informed RRT* algorithm is proposed. First, the artificial potential field (APF) method is used to make the sampling points move to the target point in the way of potential field descending, which improves the purpose and directionality of RRT tree expansion. Considering the complexity of the global environment during tree expansion, an adaptive step size is introduced to accelerate the expansion speed of the RRT tree in an unobstructed environment. Then, relevant constraints are added in the process of random tree expansion to ensure the feasibility of the generated paths. After the first reachable path is found, variable elliptic or ellipsoidal sampling domain is used to limit the selection of sampling points and the expansion range of adaptive step size, so as to accelerate the convergence of the algorithm to the asymptotic optimization. Finally, the original algorithm and the improved algorithm are compared in two-dimensional and three-dimensional complex environment. The simulation results show that the improved algorithm can find a better reachable path with a small number of iterations, lock the elliptic or ellipsoidal sampling domain faster and leave more time for path optimization. The improved algorithm performs better in path planning.

This study retains the basic structure of DRASTIC model and obtains more specific evaluation results by adding land-use type and groundwater resource yield parameters, modifying the rating scale and weight of nine parameters. Comparison of the modified DRASTIC-LY vulnerability map with the map of the original DRASTIC-LY method revealed differences in 40.49% of the study area. The risk map shows that the very high vulnerability area decreased from 2.79 to 1.67%, while the high vulnerability area increased from 18.70 to 28.86%. Areas with low vulnerability increased by 10.15%, while areas with medium vulnerability decreased by 15.01%. The areas with very high groundwater vulnerability are mainly distributed in the Hanbin area on the north bank of the Han River, the areas with high are mainly concentrated on both sides of the Fujia River, while the areas with low are distributed in most areas in the west of the basin. The Pearson's correlation factor was 0.0583 in the original DRASTIC model, 0.1113 in the DRASTIC-LY method and 0.8291 in the modified DRASTIC-LY model, which indicated that the revised DRASTIC-LY model was more appropriate than the original model. The results can help the government with the protection of water resources. HIGHLIGHTS Improve the DRASTIC model.; Determine the weight, grade and category of each parameter.; Based on the sensitivity analysis and model validation results, construct the best model suitable for groundwater vulnerability assessment.; The results of this study will help government managers improve the composition of water use and strengthen the protection of vulnerable aquifers.;

Raising the albedo (solar reflectance) of a building’s walls reduces unwanted solar heat gain in the cooling season. This saves electricity and lowers peak power demand by decreasing the need for air conditioning. It can also cool the outside air, which can mitigate the urban heat island effect and also improve air quality by slowing the reactions that produce smog. This project quantified the energy savings, peak demand reduction, urban cooling, and air quality improvements attainable from solar-reflective “cool” walls in California; collaborated with industry to assess the performance of existing cool-wall technologies, and to develop innovative cool-wall solutions; and worked with state and federal government agencies, utilities, and industry to create a cool-wall infrastructure, including application guidelines, a product rating program, incentives, and building code credits.Simulations indicate that cool walls provide annual energy savings, peak demand reduction, annual emission reduction, and summer heat island mitigation benefits comparable to those yielded by cool roofs, and are helpful across California and in most of the southern half of the United States (that is, in U.S. climate zones 1—4). Natural exposure trials conducted at three sites in California and another three sites across the United States indicate that cool-wall materials tend to stay clean and reflective. Significant advances were made in novel cool-wall technologies, such as fluorescent cool pigments that expand the color palette for cool-wall products. We prepared guidelines for the climate- and building-appropriate use of cool walls, convened a stakeholder workshop, and created a working group. Ongoing efforts seek to introduce or expand cool-wall provisions in building energy standards, green building programs, and energy efficiency incentive programs, and to develop a cool-wall product rating system.

Extranodal natural killer/T cell lymphoma (ENKTL) shows a high rate of recurrence after chemoradiotherapy. Drug resistance can be mediated by the cargo of small extracellular vesicles (sEVs). Here, we show that high abundance of the transmembrane glycoprotein CD98hc in tumor cells and serum sEVs was associated with ENKTL progression and drug resistance. Mechanistically, PEGylated-asparaginase (PEG-asp) treatment, a common therapy against ENKTL, promoted the translocation of the transcription factor ATF4 to the nucleus, where it was stabilized by USP1 and subsequently increased CD98hc expression. CD98hc delivered in tumor cell–derived sEVs increased tumor cell proliferation and drug resistance in a cultured human NK lymphoma cell line, animal models, and samples from patients with refractory/relapse ENKTL. Moreover, inhibiting both USP1 and EV secretion synergistically enhanced the cytotoxicity of PEG-asp. These data suggest that targeting CD98hc in the treatment of ENKTL may be beneficial in overcoming drug resistance. Editor's summary: Extranodal natural killer/T cell lymphoma (ENKTL) is treated with PEGylated asparaginase (PEG-asp), but drug resistance is common. Liao et al. found that limiting the trafficking of a glycoprotein could overcome drug resistance. Ubiquitin carboxyl-terminal hydrolase 1 (USP1) stabilized the transcription factor ATF4, which promoted CD98hc expression. Knocking out CD98hc in tumor cells and small extracellular vesicles (sEVs) sensitized cells to PEG-asp treatment, whereas CD98hc-enriched sEVs suppressed the effects of PEG-asp in mice, suggesting that targeting CD98hc may be explored in the treatment of ENKTL. —Amy E. Baek [ABSTRACT FROM AUTHOR]

'Duli' (Pyrus betulifolia Bunge) is one of the main rootstocks of pear trees in China. Gibberellin (GA) is a key plant hormone and the roles of GA in nitrate (NO3−) uptake and metabolism in plants remain unclear. In this study, we investigated the effects of exogenous GA3 on the N metabolism of 'Duli' seedlings under NO3− deficiency. The results showed that exogenous GA3 significantly improves 'Duli' growth under NO3− deficiency. On the one hand, GA3 altered the root architecture, increased the content of endogenous hormones (GA3, IAA, and ZR), and enhanced photosynthesis; on the other hand, it enhanced the activities of N−metabolizing enzymes and the accumulation of N, and increased the expression levels of N absorption (PbNRT2) and the metabolism genes (PbNR, PbGILE, PbGS, and PbGOGAT). However, GA3 did not delay the degradation of chlorophyll. Paclobutrazol had the opposite effect on growth. Overall, GA3 can increase NO3− uptake and metabolism and relieve the growth inhibition of 'Duli' seedlings under NO3− deficiency. [ABSTRACT FROM AUTHOR]

Rare earth resource recycling is an important endeavor for environmental protection and resource utilization. This study explores the method of preparing regenerated magnets using waste magnets as raw materials based on existing processes. By utilizing existing Nd-Fe-B production equipment, various waste magnets are transformed into recycled powder. Next, nascent Nd-Fe-B powders with slightly higher rare earth content are selected as the repairing agent. The regenerated magnets are prepared by incorporating the nascent powder into the recycled powder. The focus lies in investigating the repairing effect of the nascent powder repairing agent on the microstructure of regenerated magnets and exploring the influence of sintering temperature and powder addition on the magnetic properties and microstructure of the regenerated magnets. The results showed that the nascent powder increased the proportion of grain boundary phases and effectively repaired the grain boundary structure of the regenerated magnets. In addition, the Pr element in the nascent powder replaces the Ce element in the recycled powder, which ultimately improves the magnetic properties of the regenerated magnet in a comprehensive manner. This study provides valuable insights and guidance for rare earth resource recycling and the preparation of regenerated magnets. [ABSTRACT FROM AUTHOR]

Objective To explore the technology and efficacy of fabrication of a guide and removal of a fiber post by tetrahedron positioning technology at the chair side.Methods For one patient with acute chronic periapical periodontitis of the left maxillary lateral incisor who needed to have the fiber post removed, the chair side tetrahedral positioning technique was used to make a guide plate to remove the fiber post. Cone beam CT (CBCT) data were imported into the software to design the guide plate for fiber post removal. The guide plate design on CBCT was transferred to a solid model by using tetrahedral positioning technology. The guide plate was made to guide the removal of the fiber post, and then left maxillary lateral incisor root canal was performed. We evaluated the effect of fiber post removal with tetrahedral positioning technology by reviewing the literature.Results The guide plate made by tetrahedral positioning technology can accurately locate the position and direction of fiber posts at a low cost and with high speed. After the fiber post was removed, the root canal could be dredged by using root canal preparation instruments. After root canal preparation, the root canal was filled with warm gutta-percha to complete the root canal treatment. After 3 months, the apical radiograph showed that the transmission shadow of the apical area was reduced. The results of the literature review showed that the fiber post removal with guide plates provides a predictable result and a lower risk of iatrogenic damage. Minimally invasive treatment can be carried out, and chair time can be reduced.Conclusion On the basis of CBCT data, using tetrahedral positioning technology to make fiber post removal guides can help reduce the risk of fiber post removal and has the characteristics of speed, low cost and short chair side processing. However, the accuracy comparison between tetrahedral positioning technology and 3D printing guides needs further study.