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Background and aimsAn increasing number of studies have confirmed that non-textbook outcomes (non-TO) are a risk factor for the long-term outcome of malignant tumors. It is particularly important to identify the predictive factors of non-TO to improve the quality of surgical treatment. We attempted to construct two nomograms for preoperative and postoperative prediction of non-TO after laparoscopic hepatectomy for hepatocellular carcinoma (HCC).MethodsPatients who underwent curative-intent hepatectomy for HCC between 2014 and 2021 at two Chinese hospitals were analyzed. Using univariate and multivariate analyses, the independent predictors of non-TO were identified. The prediction accuracy is accurately measured by the receiver operating characteristic (ROC) curve and calibration curve. ROC curves for the preoperative and postoperative models, Child–Pugh grade, BCLC staging, and 8th TNM staging were compared relative to predictive accuracy for non-TO.ResultsAmong 515 patients, 286 patients (55.5%) did not achieve TO in the entire cohort. Seven and eight independent risk factors were included in the preoperative and postoperative predictive models by multivariate logistic regression analysis, respectively. The areas under the ROC curves for the postoperative and preoperative models, Child–Pugh grade, BCLC staging, and 8th TNM staging in predicting non-TO were 0.762, 0.698, 0.579, 0.569, and 0.567, respectively.ConclusionOur proposed preoperative and postoperative nomogram models were able to identify patients at high risk of non-TO following laparoscopic resection of HCC, which may guide clinicians to make individualized surgical decisions, improve postoperative survival, and plan adjuvant therapy against recurrence.

While a large variety of organic and molecular materials have been found to exhibit charge memory effects, the underlying mechanism is not well-understood, which hinders rational device design. Here, we study the charge retention mechanism of a nanoscale memory system, an organic monolayer on a silicon substrate, with Au nanoparticles on top serving as the electrical contact. Combining scanning probe imaging/manipulation and density functional simulations, we observe stable charge retention effects in the system and attributed it to polaron effects at the amine functional groups. Our findings can pave the way for applications in nonvolatile memory, neuromorphic computing, and high dielectric breakdown devices.

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Halide perovskites are of great interest because of their large potential for a broad range of applications, such as photovoltaics, light-emitting diodes, and photodetectors. However, currently the state-of-the-art highly emissive halide perovskite materials contain toxic lead ions, and the synthesis of color-stable efficient blue-emissive perovskite analogs remains challenging. The discovery of lead-free, non-toxic halide materials with efficient blue light emission is promising for practical light-emitting applications. Here, we have discovered a series of highly blue-emissive all-inorganic Cu(I)-containing rare-earth halide compounds in the solid state at room temperature. The Cu(I) ions in the compounds show a 3-coordination geometry with the halide ions and connect Sc-Cl octahedra to form clusters in alternating layers, which play a crucial role in the regulation of the electronic structure and emission properties of this series of rare-earth halide cluster compounds.

The mixed quantum-classical nonadiabatic molecular dynamics (NAMD) is a powerful tool to study many phenomena, especially ultrafast carrier transport and cooling. Carrier decoherence and detailed balance are two major issues in NAMD. So far, there is no computationally inexpensive approach to incorporate both effects. While the decoherence effect can be easily included in the state density matrix formalism and the detailed balance can be included in surface hopping or the wave function collapse approach, it is difficult to include both of them in a unified formalism. In this work we introduce a state density matrix formalism (referred to as P-matrix) including both the decoherence and detailed balance effects for NAMD. This method is able to explicitly treat the decoherence between different pairs of adiabatic states. Moreover, the off-diagonal density matrix elements are divided into two parts, corresponding to energy-increasing and energy-decreasing transitions. The detailed balance is then enforced by a Boltzmann factor applied to the energy-increasing transition part. The P-matrix formalism is applied to study hot-hole cooling and transfer processes in Si quantum dot (QD) systems. The calculated hot-carrier relaxation time is consistent with experiments. In a QD-pair system, the hot-hole cooling time shows weak dependence on the QD spacing. However, the hot-carrier transfer rate from one QD to another is found to decrease exponentially with the QD-QD distance. When the QD spacing is small (∼1 nm), the hot-carrier transfer can be very efficient. It is also shown that the explicit treatment of decoherence time is important in order to treat this hot-carrier transfer correctly.

Auger recombination is the main non-radiative decay pathway for multi-carrier states of colloidal quantum dots, which affects performance of most of their optical and optoelectronic applications. Outstanding single-exciton properties of CdSe/CdS core/shell quantum dots enable us to simultaneously study the two basic types of Auger recombination channels-negative trion and positive trion channels. Though Auger rates of positive trion are regarded to be much faster than that of negative trion for II-VI quantum dots in literature, our experiments find the two rates can be inverted for certain core/shell geometries. This is confirmed by theoretical calculations as a result of geometry-dependent dielectric screening. By varying the core/shell geometry, both types of Auger rates can be independently tuned for ~ 1 order of magnitude. Experimental and theoretical findings shed new light on designing quantum dots with necessary Auger recombination characteristics for high-power light-emitting-diodes, lasers, single-molecular tracking, super-resolution microscope, and advanced quantum light sources.

Colloidal cesium lead halide perovskite nanocrystals exhibit unique photophysical properties including high quantum yields, tunable emission colors, and narrow photoluminescence spectra that have marked them as promising light emitters for applications in diverse photonic devices. Randomly oriented transition dipole moments have limited the light outcoupling efficiency of all isotropic light sources, including perovskites. In this report we design and synthesize deep blue emitting, quantum confined, perovskite nanoplates and analyze their optical properties by combining angular emission measurements with back focal plane imaging and correlating the results with physical characterization. By reducing the dimensions of the nanocrystals and depositing them face down onto a substrate by spin coating, we orient the average transition dipole moment of films into the plane of the substrate and improve the emission properties for light emitting applications. We then exploit the sensitivity of the perovskite electronic transitions to the dielectric environment at the interface between the crystal and their surroundings to reduce the angle between the average transition dipole moment and the surface to only 14° and maximize potential light emission efficiency. This tunability of the electronic transition that governs light emission in perovskites is unique and, coupled with their excellent photophysical properties, introduces a valuable method to extend the efficiencies and applications of perovskite based photonic devices beyond those based on current materials.

Purpose: We investigated the association between transient receptor potential vanilloid (TRPV) expression in human urothelium tissue and lower urinary tract dysfunction (LUTD). Materials and Methods: We prospectively enrolled men who planned to undergo surgical treatment for benign prostatic obstruction to analyze TRPV1 and TRPV4 expression in the urothelium using enzyme-linked immunosorbent assay and immunofluorescence staining. Patients were divided into two groups based on urodynamics: the detrusor underactivity (DU) group and the non-DU group. Levels of TRPV1 and TRPV4 were compared between the two groups. We also divided patients into two groups according to degree of subjective urinary urgency symptoms using a 5-point urinary sensation scale and compared the differences in TRPV1 and TRPV4 levels between the two groups. The correlations between urodynamic parameters with TRPV1 or TRPV 4 in all patients were also analyzed. Results: The levels of TRPV1 and TRPV 4 were not significantly different between the DU group (n=10) and the non-DU group (n=11). When we divided the patients according to degree of subjective urgency, the level of TRPV1 was not significantly different between the urgency group (n=10) and the non-urgency group (n =11), but the level of TRPV4 was significantly increased in the urgency group (p=0.029). There was no significant correlation between the level of TRPV1 or TRPV4 and urodynamic parameters in any patients. Conclusions: TRPV4 could be a useful diagnostic biomarker for patients with LUTD.

We introduce a general surface passivation mechanism for cesium lead halide perovskite materials (CsPbX3, X = Cl, Br, I) that is supported by a combined experimental and theoretical study of the nanocrystal surface chemistry. A variety of spectroscopic methods are employed together with ab initio calculations to identify surface halide vacancies as the predominant source of charge trapping. The number of surface traps per nanocrystal is quantified by 1H NMR spectroscopy, and that number is consistent with a simple trapping model in which surface halide vacancies create deleterious under-coordinated lead atoms. These halide vacancies exhibit trapping behavior that differs among CsPbCl3, CsPbBr3, and CsPbI3. Ab initio calculations suggest that introduction of anionic X-type ligands can produce trap-free band gaps by altering the energetics of lead-based defect levels. General rules for selecting effective passivating ligand pairs are introduced by considering established principles of coordination chemistry. Introducing softer, anionic, X-type Lewis bases that target under-coordinated lead atoms results in absolute quantum yields approaching unity and monoexponential luminescence decay kinetics, thereby indicating full trap passivation. This work provides a systematic framework for preparing highly luminescent CsPbX3 nanocrystals with variable compositions and dimensionalities, thereby improving the fundamental understanding of these materials and informing future synthetic and post-synthetic efforts toward trap-free CsPbX3 nanocrystals.