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Photoinduced interfacial charge transfer plays a critical role in energy conversion involving van der Waals (vdW) heterostructures constructed of inorganic nanostructures and organic materials. However, the effect of molecular stacking configurations on charge transfer dynamics is less understood. In this study, we demonstrated the tunability of interfacial charge separation in a type-II heterojunction between monolayer (ML) WS2 and an organic semiconducting molecule [2-(3″,4-dimethyl-[2,2:5,2:5″,2″-quaterthiophen]-5-yl)ethan-1-ammonium halide (4Tm)] by rational design of relative stacking configurations. The assembly between ML-WS2 and the 4Tm molecule forms a face-to-face stacking when 4Tm molecules are in a self-aggregation state. In contrast, a face-to-edge stacking is observed when 4Tm molecule is incorporated into a 2D organic-inorganic hybrid perovskite lattice. The face-to-face stacking was proved to be more favorable for hole transfer from WS2 to 4Tm and led to interlayer excitons (IEs) emission. Transient absorption measurements show that the hole transfer occurs on a time scale of 150 fs. On the other hand, the face-to-edge stacking resulted in much slower hole transfer without formation of IEs. This inefficient hole transfer occurs on a similar time scale as A exciton recombination in WS2, leading to the formation of negative trions. These investigations offer important fundamental insights into the charge transfer processes at organic-inorganic interfaces.

Background: Chemotherapy-induced thrombocytopenia (CIT) commonly exacerbates the difficulty of cancer treatment, increasing bleeding risks and potentially reducing chemotherapy dosage, ultimately impacting its efficacy. However, there are limited studies about avatrombopag application in acute lymphoblastic leukemia (ALL) CIT. Objectives: We aimed to evaluate the efficacy and safety of avatrombopag in treating CIT patients diagnosed with ALL. Design: This retrospective study, using propensity score matching, included 42 pairs of cases treated with and without avatrombopag (CAT: 54 cases, CAT+: 30 cases). Methods: Data of CIT-ALL children were retrospectively collected. The primary endpoint was platelet count (PC) response rate on day 10 ± 2 (defined as an increase of PC to ⩾75 × 10 9 /L with the exclusion of platelet transfusion). Secondary efficacy endpoints, safety endpoints, and factors that predict PC response were also analyzed. Results: In the avatrombopag group, the PC response rate was prominently higher on day 10 ± 2 (89.1%) versus the control group (56.4%, p = 0.005). On day 10 ± 2, the difference in median PC change from baseline was predominantly distinct in the avatrombopag group compared to the control group ( p = 0.001). In the avatrombopag group, platelet recovery to ⩾25 and ⩾50 × 10 9 /L was faster ( p = 0.001, p = 0.002), and quicker platelet reaching ⩾75 × 10 9 /L and ⩾100 × 10 9 /L was achieved ( p = 0.023, p = 0.011). The avatrombopag group not only increased the nadir PC ( p = 0.009) but also reduced the total platelet transfusion compared to the control group ( p = 0.047). Only one case (2.4%) experienced bleeding events after medication. Nine cases of secondary thrombocythemia were noted without other adverse events. There was no difference in event-free survival between the two groups ( p = 0.648). Drug administration was prediction factor for PC response. Conclusion: Avatrombopag is a potentially safe and effective treatment option for CIT in pediatric ALL.

Electroluminescence efficiencies and stabilities of quasi-two-dimensional halide perovskites are restricted by the formation of multiple-quantum-well structures with broad and uncontrollable phase distributions. Here, we report a ligand design strategy to substantially suppress diffusion-limited phase disproportionation, thereby enabling better phase control. We demonstrate that extending the π-conjugation length and increasing the cross-sectional area of the ligand enables perovskite thin films with dramatically suppressed ion transport, narrowed phase distributions, reduced defect densities, and enhanced radiative recombination efficiencies. Consequently, we achieved efficient and stable deep-red light-emitting diodes with a peak external quantum efficiency of 26.3% (average 22.9% among 70 devices and cross-checked) and a half-life of ~220 and 2.8 h under a constant current density of 0.1 and 12 mA/cm2, respectively. Our devices also exhibit wide wavelength tunability and improved spectral and phase stability compared with existing perovskite light-emitting diodes. These discoveries provide critical insights into the molecular design and crystallization kinetics of low-dimensional perovskite semiconductors for light-emitting devices.

Electronic and optical excitations in two-dimensional systems are distinctly sensitive to the presence of a moiré superlattice. We used cryogenic transmission electron microscopy and spectroscopy to simultaneously image the structural reconstruction and associated localization of the lowest-energy intralayer exciton in a rotationally aligned WS2-WSe2 moiré superlattice. In conjunction with optical spectroscopy and ab initio calculations, we determined that the exciton center-of-mass wave function is confined to a radius of approximately 2 nanometers around the highest-energy stacking site in the moiré unit cell. Our results provide direct evidence that atomic reconstructions lead to the strongly confining moiré potentials and that engineering strain at the nanoscale will enable new types of excitonic lattices.

Carbon material is an important additive in energetic materials. Graphene is a monolayer carbon material in which carbon atoms are arranged in two-dimensional honeycomb structure, who has special optical, electrical, and mechanical properties. Recently, the application of graphene-based composites in energetic materials has received extensive attention. This review mainly summarizes the applications of graphene and graphene-based nanomaterials in energetic materials. The effects of these materials on the thermal stability, sensitivity, mechanical property, ignition and combustion of energetic materials were discussed. Furthermore, the progress of functionalized modification of graphene has been summarized, including covalent bonding modification and doping modification. These studies show that graphene-based materials exhibit excellent performances and might emerge as promising candidate for energetic materials.

Surface passivation is an effective way to boost the efficiency and stability of perovskite solar cells (PSCs). However, a key challenge faced by most of the passivation strategies is reducing the interface charge recombination without imposing energy barriers to charge extraction. Here, a novel multifunctional semiconducting organic ammonium cationic interface modifier inserted between the light-harvesting perovskite film and the hole-transporting layer is reported. It is shown that the conjugated cations can directly extract holes from perovskite efficiently, and simultaneously reduce interface non-radiative recombination. Together with improved energy level alignment and the stabilized interface in the device, a triple-cation mixed-halide medium-bandgap PSC with an excellent power conversion efficiency of 22.06% (improved from 19.94%) and suppressed ion migration and halide phase segregation, which lead to a long-term operational stability, is demonstrated. This strategy provides a new practical method of interface engineering in PSCs toward improved efficiency and stability.

Objective To evaluate the safety and efficacy of the collection of peripheral blood stem cells (PBSCs) in pediatric patients with thalassemia major (TM) weighing 20 kg or less. Methods PBSCs collection data of 170 pediatric patients with TM weighing 20 kg or less from January 2013 to December 2020 in our center were reviewed. Safety was assessed by the occurrence of adverse events during apheresis procedures, and efficacy was evaluated by the number of CD34+ cells collected. Results A total of 171 PBSCs procedures were performed on 170 patients with TM weighing 20 kg or less, with a median age of (4.98±1.53) years and a median weight of (17.30±2.18) kg. The probability of collecting at least 1×106 CD34+ cells/kg during a single course of apheresis was 99.41% (169/170), with a median (5.88±4.23) ×106 CD34+ cells collected per kg of weight of the recipient. A minimum pre-apheresis hemoglobin (Hb) of 60 g/L in patients with TM weighing 20 kg or less was safe and feasible. The most common adverse event of G-CSF mobilization in TM patients is bone pain, with the incidence of 7.65% (13/170), which was higher than that of healthy children donors in our center. The most common adverse events during the collection were pain at the puncture site of the femoral vein (6.47%, 11/170) and low pressure of the fluid (2.92%, 5/170). And no serious complications related to PBSCs mobilization, central venous catheter(CVC)placement or the apheresis procedure occurred. Conclusion PBSCs collection by COM.TEC blood cell separator in children weighing 20 kg or less is safe and efficacious.

Two-dimensional perovskites that could be regarded as natural organic-inorganic hybrid quantum wells (HQWs) are promising for light-emitting diode (LED) applications. High photoluminescence quantum efficiencies (approaching 80%) and extremely narrow emission bandwidth (less than 20 nm) have been demonstrated in their single crystals; however, a reliable electrically driven LED device has not been realized owing to inefficient charge injection and extremely poor stability. Furthermore, the use of toxic lead raises concerns. Here, we report Sn(II)-based organic-perovskite HQWs employing molecularly tailored organic semiconducting barrier layers for efficient and stable LEDs. Utilizing femtosecond transient absorption spectroscopy, we demonstrate the energy transfer from organic barrier to inorganic perovskite emitter occurs faster than the intramolecular charge transfer in the organic layer. Consequently, this process allows efficient conversion of lower-energy emission associated with the organic layer into higher-energy emission from the perovskite layer. This greatly broadened the candidate pool for the organic layer. Incorporating a bulky small bandgap organic barrier in the HQW, charge transport is enhanced and ion migration is greatly suppressed. We demonstrate a HQW-LED device with pure red emission, a maximum luminance of 3466 cd m-2, a peak external quantum efficiency up to 3.33%, and an operational stability of over 150 h, which are significantly better than previously reported lead-free perovskite LEDs.

Background Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is currently the only curative treatment for thalassaemia major (TM). Cord blood (CB) from a sibling has different characteristics from marrow and has potential advantages and disadvantages as a stem cell source.Methods We retrospectively analyzed 68 children with beta-thalassaemia major (β-TM) who underwent fresh cord blood transplantation (F-CBT) from an HLA-matched sibling donor (MSD) between June 2010 and July 2018 in the Department of Pediatrics, Nanfang Hospital and Haematology-Oncology, Shenzhen Children’s Hospital.Results The median infused doses of total nucleated cells (TNCs) and CD34 + cells were 8.51×107/kg and 3.16×105/kg, respectively. The median time to neutrophil and platelet engraftment were, respectively, 27 and 31 days. The cumulative probabilities of acute and chronic graft-versus-host disease (GVHD) were very low after F-CBT (7.8% and 0.0%, respectively). Of the 68 paediatric patients, 67 patients survived during a median follow-up period of 61 months. The estimated 5-year probability of overall survival (OS) and disease-free survival (DFS) were 98.5% and 87.9%, respectively. Three patients experienced graft rejection (GR) (4.5%), and we identified CD34 + cell dose as a significant risk factor for graft failure (p = 0.036) in stratify analysis.Conclusions The above results indicate that patients with β-TM have excellent outcomes after F-CBT from an HLA-MSD.

Marketers are adopting increasingly sophisticated ways to engage with customers throughout their journeys. We extend prior perspectives on the customer journey by introducing the role of digital signals that consumers emit throughout their activities. We argue that the ability to detect and act on consumer digital signals is a source of competitive advantage for firms. Technology enables firms to collect, interpret, and act on these signals to better manage the customer journey. While some consumers' desire for privacy can restrict the opportunities technology provides marketers, other consumers' desire for personalization can encourage the use of technology to inform marketing efforts. We posit that this difference in consumers' willingness to emit observable signals may hinge on the strength of their relationship with the firm. We next discuss factors that may shift consumer preferences and consequently affect the technology-enabled opportunities available to firms. We conclude with a research agenda that focuses on consumers, firms, and regulators., Author(s): David A. Schweidel [sup.1] , Yakov Bart [sup.2] , J. Jeffrey Inman [sup.3] , Andrew T. Stephen [sup.4] , Barak Libai [sup.5] , Michelle Andrews [sup.1] , Ana Babic [...]

Transport of energy carriers in solid-state materials is determined by their wavefunctions and interactions with the environment. While quantum transport theory has predicted distinct transport in the intermediate coupling regime resulting from the intricate interplay between coherent wave-like and incoherent particle-like mechanisms, these predictions are awaiting experimental evidence. Here we demonstrate quantum transport signatures in perovskite nanocrystal superlattices by imaging exciton propagation with high spatial and temporal resolutions over 7-298 K. At 7 K, coherent propagation of the excitons dominates, with transient ballistic motion within a coherence length of up to 40 nanocrystal sites. The interference of the wave-like motion leads to Anderson Localization in the long-time limit. As temperature increases, a peak in the long-time diffusion constant is observed at a temperature where static disorder and dephasing are balanced, which substantiates evidence for environment-assisted quantum transport. Our results connect theoretical predictions and experiments using a stochastic Anderson localization model, highlighting perovskite nanocrystals as promising building blocks for quantum materials. The interplay between coherent wave-like and incoherent particle-like transport can lead to environment-assisted quantum transport. Using time resolved microscopies and theoretical modeling, the authors show signatures of this enhanced transport regime in perovskite nanocrystal superlattices. [ABSTRACT FROM AUTHOR]

The deterministic non‐autonomous multispecies Holling type II model and its stochastic version with a simple type of noise have been proposed to infer multispecies community structure. However, these models fail to account for complex types of noises, which may render the model overly simplistic. In this paper, a non‐autonomous multispecies Holling type II model with a complex type of noise has been proposed. We establish sufficient conditions for various mathematical properties of the solutions, including existence and uniqueness, stochastic permanence and extinction. Additionally, numerical simulation studies are provided to illustrate our theoretical findings. [ABSTRACT FROM AUTHOR]

The role of the alkali metal cations in halide perovskite solar cells is not well understood. Using synchrotron-based nano-x-ray fluorescence and complementary measurements, we found that the halide distribution becomes homogenized upon addition of cesium iodide, either alone or with rubidium iodide, for substoichiometric, stoichiometric, and overstoichiometric preparations, where the lead halide is varied with respect to organic halide precursors. Halide homogenization coincides with long-lived charge carrier decays, spatially homogeneous carrier dynamics (as visualized by ultrafast microscopy), and improved photovoltaic device performance. We found that rubidium and potassium phase-segregate in highly concentrated clusters. Alkali metals are beneficial at low concentrations, where they homogenize the halide distribution, but at higher concentrations, they form recombination-active second-phase clusters.