Search

In the e-commerce last-mile delivery process, the asset operators (logistics service providers who own parcel locker facilities) support their delivery service with parcel lockers, while the non-asset operators (logistics service providers without parcel lockers) perform door-to-door delivery. Due to demand fluctuation, asset operators' parcel-locker slots may be left vacant, while non-asset operators are stuck with the high-cost door-to-door service. The exclusiveness of parcel-locker usage reduces resource utilization and service efficiency in last-mile delivery. Therefore, this paper proposes a parcel-locker-sharing model in which these two parties share the parcel-locker capacity in last-mile delivery. The asset operator rents the unused parcel lockers to the non-asset operator by charging a rental fee,while the non-asset operator rents the parcel lockers for delivery to save logistics costs. The motivation of this alliance is to increase the profits of both parties and that of the total supply chain. This study establishes the supply-chain profit model for the parcel-locker-sharing framework and finds that the profit or loss depends on the comparison of the operation cost savings and delivery-cost savings. A numerical analysis is conducted to validate the final result. The research further suggests the optimal rental quantity and price interval. This paper is the first to study the operational mechanism of sharing the parcel locker between two distinct types of logistics service providers and to offer recommendations for industrial application. [ABSTRACT FROM AUTHOR]

The outstanding advantages of lightweight and flexibility enable flexible perovskite solar cells (PSCs) to have great application potential in mobile energy devices. Due to the low cost, low-temperature processibility, and high electron mobility, SnO2 nanocrystals have been widely employed as the electron transport layer in flexible PSCs. To prepare high-quality SnO2 layers, a monodispersed nanocrystal solution is normally used. However, the SnO2 nanocrystals can easily aggregate, especially after long periods of storage. Herein, we develop a green and cost-effective strategy for the synthesis of high-quality SnO2 nanocrystals at low temperatures by introducing small molecules of glycerol, obtaining a stable and well-dispersed SnO2-nanocrystal isopropanol dispersion successfully. Due to the enhanced dispersity and super wettability of this alcohol-based SnO2-nanocrystal solution, large-area smooth and dense SnO2 films are easily deposited on the plastic conductive substrate. Furthermore, this contributes to effective charge transfer and suppressed non-radiative recombination at the interface between the SnO2 and perovskite layers. As a result, a greatly enhanced power conversion efficiency (PCE) of 21.8% from 19.2% is achieved for small-area flexible PSCs. A large-area 5 cm × 5 cm flexible perovskite solar mini-module with a champion PCE of 16.5% and good stability is also demonstrated via this glycerol-modified SnO2-nanocrystal isopropanol dispersion approach. [ABSTRACT FROM AUTHOR]

Converting PbI2 residues into low‐dimensional perovskites through post‐treatment with ammonium‐based large cations can passivate 3D perovskites, thus has emerged as an effective strategy to improve the performance of perovskite solar cells (PSCs). Herein, a dramatically improved efficiency is demonstrated for PSCs based on a two‐step‐processed FAPbI3 perovskite via post‐treatment with formamidinium (FA)‐based benzamidine hydrochloride (PFACl), outperforming the commonly used methylamine (MA)‐based benzylamine hydrochloride (PMACl). With an in‐depth exploration of the crystal structures and morphology changes of the FAPbI3 perovskite upon the PFACl post‐treatment, the preferential formation of 1D rather than 2D structures on the 3D perovskite film is identified. In contrast to the 2D counterpart, the more energetically favorable 1D structure enables a more effective elimination of PbI2 residues. As a consequence, the PFACl‐induced 1D/3D perovskite film is endowed with smoother morphology, more uniform surface potential distribution, lower trap density, faster charge transfer, and better film stability than the PMACl‐induced 2D/3D perovskite and control films, demonstrating champion efficiencies of 24.9% for a small‐size PSC, 23.6% for a 1 cm2 large‐size PSC, and 21.2% for a 5 × 5 cm2 mini‐module, which is the highest among the perovskite solar mini‐modules using the two‐step deposition method. [ABSTRACT FROM AUTHOR]

Aims: To compare healthcare resource utilization (HRU) and costs between patients with or without melanoma recurrence and between patients with distant or locoregional melanoma recurrence., Methods: Patients aged ≥65 years with completely resected, stage IIB/IIC or III melanoma were identified from Surveillance, Epidemiology, and End Results-Medicare data and stratified based on whether they experienced a recurrence, and whether it was distant or locoregional (separately for each stage). The index date was the date of recurrence (recurrence group) or a randomly assigned date (non-recurrence group). Patients in the recurrence and non-recurrence groups were propensity score-matched 1:1 based on patient characteristics; HRU and healthcare costs were compared between the 2 groups and between patients with distant or locoregional recurrence during the ≤24 months following index., Results: After matching, 507 pairs of patients with recurrent or non-recurrent stage IIB/IIC melanoma (236 patients with distant recurrence, 271 with locoregional) and 141 pairs of patients with recurrent or non-recurrent stage III melanoma (50 patients with distant recurrence, 91 with locoregional) were included. During the first year following recurrence, unadjusted HRU was generally higher in patients with versus without recurrence and patients with distant versus locoregional recurrence among both stage IIB/IIC and III cohorts. Patients who experienced recurrence incurred $6,474 (stage IIB/IIC) or $6,112 (stage III) per patient per month (PPPM) more in unadjusted, all-cause, total healthcare costs than patients without recurrence (both p  < 0.001). Patients with distant recurrence incurred $7,292 (stage IIB/IIC) or $5,436 (stage III) PPPM more in unadjusted, all-cause, total healthcare costs than patients with locoregional recurrence (both p  < 0.05)., Limitations: Melanoma recurrence was identified using a claims-based algorithm., Conclusions: Economic burden is higher in patients with versus without melanoma recurrence and patients with distant versus locoregional recurrence. There is a high unmet need for adjuvant therapies that may help to prevent or delay recurrence.